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Caldera, Christian; Berndt, René; Eggeling, Eva; Schröttner, Martin; Fellner, Dieter W.

"Mining Bibliographic Data" - Using Author's Publication History for a Brighter Reviewing Future within Conference Management Systems

2014

International Journal on Advances in Intelligent Systems

Organizing and managing a conference is a cumbersome and time consuming task. Electronic conference management systems support reviewers, conference chairs and the International Programme Committee members (IPC) in managing the huge amount of submissions. These systems implement the complete workflow of scientific conferences. One of the most time consuming tasks within a conference is the assignment of IPC members to the submissions. Finding the best-suited person for reviewing a paper strongly depends on the expertise of the IPC member. There are already various approaches like "bidding" or "topic matching". However, these approaches allocate a considerable amount of resources on the IPC member side. This article introduces how the workflow of a conference looks like and what the challenges for an electronic conference management are. It will take a close look on the latest version of the Eurographics Submission and Review Management system (SRMv2). Finally, it will introduce an extension of SRMv2 called the Paper Rating and IPC Matching Tool (PRIMA), which reduces the workload for both - IPC members and chairs - to support and improve the assignment process.

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Gutzeit, Enrico; Kloß, Enrico; Schröder, Andreas

3D-Registrierung zum Soll-Ist-Vergleich auf Basis unterschiedlicher Geometriedateiformate

2014

3D-NordOst 2014

Anwendungsbezogener Workshop zur Erfassung, Modellierung, Verarbeitung und Auswertung von 3D-Daten (3D-NordOst) <17, 2014, Berlin, Germany>

Der Soll-Ist-Vergleich ist eine notwendige Maßnahme zur Sicherung der Qualität gefertigter Bauteile. Zur Automatisierung des Soll-Ist-Vergleiches sind eine einheitliche Repräsentation der Geometrie und eine robuste 3D-Registrierung notwendig. In diesem Beitrag wird eine Methode zur 3D-Registrierung auf Basis verschiedener Geometriedateiformate großer technischer Objekte vorgestellt. Ausgehend von einem Laserscan (Ist-Modell) und einem CAD-Format (Soll-Modell) wird eine einheitliche Dreiecksrepräsentation generiert. Anhand der einheitlichen Repräsentation, dem weitverbreiteten STL-Format, wird eine dreistufige 3D-Registrierung vorgenommen. In der ersten Stufe werden aus den Dreiecken geeignete Punkte generiert. In der zweiten Stufe werden die Punktwolken anhand von lokalen Merkmalen grob vorregistriert und in der letzten und dritten Stufe diese genau aufeinander registriert. Durch die Anbindung der Funktionalität an eine CAD/CAM Software, wie bspw. DCAM, ergeben sich eine einfach handhabbare 3D-Registrierung und eine Basis für einen anschließenden Soll-Ist-Vergleich.

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Flach, Guntram [Betreuer]; Frenzel, Chathy [Hrsg.]

9. Rostocker eGovernment-Forum 2014 - Sicheres eGovernment: Herausforderung und Notwendigkeit

2014

Rostocker eGovernment-Forum <9, 2014, Rostock-Warnemünde, Germany>

Das 9. Rostocker eGovernment-Forum verfolgt das Ziel, anhand von Fachvorträgen und Praxisbeispielen neuartige Konzepte und Lösungen aus den Themenbereichen IT-Sicherheit, Open Government, mobile Anwendungen, Cloud Computing und Optimierung von Verwaltungsprozessen vorzustellen und Gelegenheit zu einem Gedanken- und Erfahrungsaustausch zu schaffen. Der vorliegende Tagungsband dokumentiert mit seinen Kurzfassungen ein anspruchsvolles Vortragsprogramm.

  • 978-3-95545-095-3
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A Benchmarking Model for Sensors in Smart Environments

2014

Ambient Intelligence

European Conference on Ambient Intelligence (AmI) <11, 2014, Eindhoven, The Netherlands>

In smart environments, developers can choose from a large variety of sensors supporting their use case that have specific advantages or disadvantages. In this work we present a benchmarking model that allows estimating the utility of a sensor technology for a use case by calculating a single score, based on a weighting factor for applications and a set of sensor features. This set takes into account the complexity of smart environment systems that are comprised of multiple subsystems and applied in non-static environments. We show how the model can be used to find a suitable sensor for a use case and the inverse option to find suitable use cases for a given set of sensors. Additionally, extensions are presented that normalize differently rated systems and compensate for central tendency bias. The model is verified by estimating technology popularity using a frequency analysis of associated search terms in two scientific databases.

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Zeiß, Steeven; Marinc, Alexander; Braun, Andreas; Große-Puppendahl, Tobias; Beck, Sebastian

A Gesture-Based Door Control Using Capacitive Sensors

2014

Distributed, Ambient, and Pervasive Interactions

International Conference on Distributed, Ambient and Pervasive Interactions (DAPI) <2, 2014, Heraklion, Crete, Greece>

In public places sanitary conditions are always of concern, particularly of surfaces that are touched by a multitude of persons, such as door handles in rest rooms. Similar issues also arise in medical facilities. Doors that open based on presence are common in environments such as shopping malls; however they are not suited for sensitive areas, such as toilet stalls. Capacitive proximity sensors detect the presence of the human body over a distance and can be unobtrusively applied in order to enable hidden gesture-based interfaces that work without touch. In this paper we present a concept for a gesture controlled automated door based on this sensor technology. We introduce the underlying technology and present the concept and electronic components used in detail. Novel interaction patterns and data processing methods allow to open, close, lock and unlock the door using simple gestures. A prototype device has been created and evaluated in a user study.

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Filippo, Francesco De; Stork, André; Schmedt, Hendrik; Bruno, Fabio

A Modular Architecture for a Driving Simulator Based on the FDMU Approach

2014

IJIDeM - International Journal on Interactive Design and Manufacturing

The present paper describes the development of a modular and easily configurable simulation platform for ground vehicles. This platform should be usable for the implementation of driving simulators employed both in training purposes and in vehicle components testing. In particular, the paper presents a first architectural model for the implementation of a simulation platform based on the Functional Digital Mock-Up (FDMU) approach. This platform will allow engineers to implement different kinds of simulators that integrate both physical and virtual components, thus achieving the possibility to quickly reconfigure the architecture depending on the hardware and software used and on specific test case needs. The platform has been tested by developing a case study that integrates a motion platform, some I/O devices and a simple dynamic ground vehicle model implemented in OpenModelica.

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Le Moan, Steven; Urban, Philipp

A New Connection Space for Low-Dimensional Spectral Color Management

2014

Measuring, Modeling, and Reproducing Material Appearance

Measuring, Modeling, and Reproducing Material Appearance (MMRMA) <1, 2014, San Francisco, CA, USA>

Multi- or hyper-spectral pixels are usually represented as vectors with high dimensionality. For many applications, not all of these dimensions are actually necessary, and a few values are enough to measure and/or process the pixel with a very good accuracy. In this work, we introduce a new strategy to reduce the dimensionality of spectral images ranging in the visible wavelengths, for purposes of color management. We define a new Interim Connection Space (ICS) that contains only five dimensions, and show that it has numerous advantages over state-of-the-art ICS such as LabPQR. In particular, it allows for a better spectral reconstruction accuracy.

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A p-Multigrid Algorithm using Cubic Finite Elements for Efficient Deformation Simulation

2014

VRIPHYS 14: 11th Workshop in Virtual Reality Interactions and Physical Simulations

International Workshop in Virtual Reality Interaction and Physical Simulations (VRIPHYS) <11, 2014, Bremen, Germany>

We present a novel p-multigrid method for efficient simulation of co-rotational elasticity with higher-order finite elements. In contrast to other multigrid methods proposed for volumetric deformation, the resolution hierarchy is realized by varying polynomial degrees on a tetrahedral mesh. We demonstrate the efficiency of our approach and compare it to commonly used direct sparse solvers and preconditioned conjugate gradient methods. As the polynomial representation is defined w.r.t. the same mesh, the update of the matrix hierarchy necessary for co-rotational elasticity can be computed efficiently. We introduce the use of cubic finite elements for volumetric deformation and investigate different combinations of polynomial degrees for the hierarchy. We analyze the applicability of cubic finite elements for deformation simulation by comparing analytical results in a static scenario and demonstrate our algorithm in dynamic simulations with quadratic and cubic elements. Applying our method to quadratic and cubic finite elements results in speed up of up to a factor of 7 for solving the linear system.

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Schinko, Christoph; Berndt, René; Eggeling, Eva; Fellner, Dieter W.

A Scalable Rendering Framework for Generative 3D Content

2014

Proceedings Web3D 2014

International Conference on 3D Web Technology (WEB3D) <19, 2014, Vancouver, BC, Canada>

Delivering high quality 3D content through a web browser is still a challenge especially when intellectual property (IP) protection is necessary. Thus, the transfer of 3D modeling information to a client should be avoided. In our work we present a solution to this problem by introducing a server-side rendering framework. Only images are transferred to the client, the actual 3D content is not delivered. By providing simple proxy geometry it is still possible to provide direct interaction on the client. Our framework incorporates the Generative Modeling Language (GML) for the description and rendering of generative content. It is then possible to not only interact with the 3D content, but to modify the actual shape within the possibilities of the generative content. By introducing a control layer and encapsulating processing and rendering of the generative content in a so called GML Rendering Unit (GRU) it is possible to provide a scalable rendering framework.

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A Survey of Direction-Preserving Layout Strategies

2014

Proceedings of the 30th Spring Conference on Computer Graphics

Spring Conference on Computer Graphics (SCCG) <30, 2014, Smolenice, Slovakia>

In this paper we analyze different layout algorithms that preserve relative directions in geo-referenced networks. This is an important criterion for many sensor networks such as the electric grid and other supply networks, because it enables the user to match the geographic setting with the drawing on the screen. Even today, the layouts of these networks are often created manually. This is due to the requirement that these layouts must respect geographic references but should still be easy to read and understand. The range of available automatic algorithms spans from general graph layouts over schematic maps to semi-realistic drawings. At first sight, schematics seem to be a promising compromise between geographic correctness and readability. The former property exploits the mental map of the user while the latter makes it easier for the user to learn about the network structure. We investigate different algorithms for such maps together with different visualization techniques. In particular, the group of octi-linear layouts is prominent in handcrafted subway maps. These algorithms have been used extensively to generate drawings for subway maps. Also known as Metro Map layouts, only horizontal, vertical and diagonal directions are allowed. This increases flexibility and makes the resulting layout look similar to the well-known subway maps of large cities. The key difference to general graph layout algorithms is that geographic relations are respected in terms of relative directions. However, it is not clear, whether this metaphor can be transferred from metro maps to other domains. We discuss applicability of these different approaches for geo-based networks in general with the electric grid as a use-case scenario

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Fischer, Fabian; Davey, James; Fuchs, Johannes; Thonnard, Olivier; Kohlhammer, Jörn; Keim, Daniel A.

A Visual Analytics Field Experiment to Evaluate Alternative Visualizations for Cyber Security Applications

2014

EuroVA 2014

International EuroVis Workshop on Visual Analytics (EuroVA) <5, 2014, Swansea, Wales, UK>

The analysis and exploration of emerging threats in the Internet is important to better understand the behaviour of attackers and develop new methods to enhance cyber security. Fully automated algorithms alone are often not capable of providing actionable insights about the threat landscape. We therefore combine a multi-criteria clustering algorithm, tailor-made for the identification of such attack campaigns with three interactive visualizations, namely treemap representations, interactive node-link diagrams, and chord diagrams, to allow the analysts to visually explore and make sense of the resulting multi-dimensional clusters. To demonstrate the potential of the system, we share our lessons learned in conducting a field experiment with experts in a security response team and show how it helped them to gain new insights into various threat landscapes.

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Wesarg, Stefan; Jung, Florian; Steger, Sebastian

Abbildung anatomischen Wissens: Ein Kopf-/Hals-Atlas multipler gekoppelter Strukturen

2014

Endoskopie heute

Medizinische Bilddaten enthalten anatomische Informationen. Die Extraktion derselben durch manuelles Markieren ist unter Berücksichtigung der Datenmenge vor allem bei radiologischen 3D-Bilddaten nicht mehr vernünftig durchführbar. Hier helfen computerbasierte, automatische Verfahren. Nicht alle anatomischen Regionen heben sich durch deutliche Kontrastunterschiede von der Umgebung ab. Dennoch sind Radiologen in der Lage, auch solche Bereiche in den Bilddaten zuzuordnen. Für automatisch ablaufende Algorithmen besteht dabei die Herausforderung, das anatomische Wissen eines klinischen Experten in einer für den Computer verständlichen Form zu repräsentieren. Für den Kopf-/Hals-Bereich haben wir ein solches Modell entwickelt, das anatomische Strukturen enthält, die miteinander gekoppelt sind. Das Modell repräsentiert diese hinsichtlich ihrer Form und Größe als auch ihrer relativen Lage zueinander. Dabei wird zwischen aktiven und passiven Strukturen unterschieden. Erstere repräsentieren deutlich von der Umgebung abgrenzbare Bildbereiche, letztere Regionen, die nur aufgrund ihrer relativen Lage zu anderen Organen identifizierbar sind. Der neue Modellierungsansatz ist dabei einerseits flexibler als klassische atlasbasierte Segmentierungsverfahren. Andererseits sind das neue Verfahren und das dafür entwickelte Framework generisch und können mit geringen Adaptionen auch für Fragestellungen jenseits des Kopf-/Hals-Bereichs eingesetzt werden.

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Abschlussbericht - MEMO Basis, Design und Shared Services

2014

Zielstellung und Schwerpunkt des Teilprojektes "MEMO Basis, Design und Shared Services" war die Entwicklung von Konzepten und die prototypische Umsetzung von Shared Services. Diese realisieren Basisdienste für höher aggregierte MEMO-Dienste Zu den Shared Services zählen Semantik-Dienste, Empfehlungsdienste, Aggregationsdienste und Profiling-Dienste. Aufbauend auf diesen Shared Services erstellte das IGD intelligente Supportdienste für die Kommunikation mit Experten, Dienste für die semantische Suche und proaktive Bereitstellung von Informationen sowie Game-Dienste zur Vermittlung von Handlungswissen. Das Fraunhofer IGD leistete im Teilprojekt außerdem Beiträge zur Entwicklung und Umsetzung der konzeptionellen Architektur des MEMO Referenz Portals, in welchem die verschiedenen Einzeldienste nach dem Cloud-Prinzip für unterschiedliche Anwendungen verfügbar gemacht wurden. Das Fraunhofer IGD war außerdem für die Koordination der Entwicklung der Use Case Beschreibungen für das Gesamtsystem und die einzelnen zu entwickelnden Dienste verantwortlich.

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Nazemi, Kawa; Fellner, Dieter W. [Betreuer]; Wrobel, Stefan [Referent]

Adaptive Semantics Visualization

2014

Darmstadt, TU, Diss., 2014

Human access to the increasing amount of information and data plays an essential role for the professional level and also for everyday life. While information visualization has developed new and remarkable ways for visualizing data and enabling the exploration process, adaptive systems focus on users' behavior to tailor information for supporting the information acquisition process. Recent research on adaptive visualization shows promising ways of synthesizing these two complementary approaches and make use of the surpluses of both disciplines. The emerged methods and systems aim to increase the performance, acceptance, and user experience of graphical data representations for a broad range of users. Although the evaluation results of the recently proposed systems are promising, some important aspects of information visualization are not considered in the adaptation process. The visual adaptation is commonly limited to change either visual parameters or replace visualizations entirely. Further, no existing approach adapts the visualization based on data and user characteristics. Other limitations of existing approaches include the fact that the visualizations require training by experts in the field. In this thesis, we introduce a novel model for adaptive visualization. In contrast to existing approaches, we have focused our investigation on the potentials of information visualization for adaptation. Our reference model for visual adaptation not only considers the entire transformation, from data to visual representation, but also enhances it to meet the requirements for visual adaptation. Our model adapts different visual layers that were identified based on various models and studies on human visual perception and information processing. In its adaptation process, our conceptual model considers the impact of both data and user on visualization adaptation. We investigate different approaches and models and their effects on system adaptation to gather implicit information about users and their behavior. These are than transformed and applied to affect the visual representation and model human interaction behavior with visualizations and data to achieve a more appropriate visual adaptation. Our enhanced user model further makes use of the semantic hierarchy to enable a domain-independent adaptation. To face the problem of a system that requires to be trained by experts, we introduce the canonical user model that models the average usage behavior with the visualization environment. Our approach learns from the behavior of the average user to adapt the different visual layers and transformation steps. This approach is further enhanced with similarity and deviation analysis for individual users to determine similar behavior on an individual level and identify differing behavior from the canonical model. Users with similar behavior get similar visualization and data recommendations, while behavioral anomalies lead to a lower level of adaptation. Our model includes a set of various visual layouts that can be used to compose a multi-visualization interface, a sort of "'visualization cockpit"'. This model facilitates various visual layouts to provide different perspectives and enhance the ability to solve difficult and exploratory search challenges. Data from different data-sources can be visualized and compared in a visual manner. These different visual perspectives on data can be chosen by users or can be automatically selected by the system. This thesis further introduces the implementation of our model that includes additional approaches for an efficient adaptation of visualizations as proof of feasibility. We further conduct a comprehensive user study that aims to prove the benefits of our model and underscore limitations for future work. The user study with overall 53 participants focuses with its four conditions on our enhanced reference model to evaluate the adaptation effects of the different visual layers.

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Adaptive Visualization of Linked-Data

2014

Advances in Visual Computing. 10th International Symposium, ISVC 2014

International Symposium on Visual Computing (ISVC) <10, 2014, Las Vegas, NV, USA>

Adaptive visualizations reduces the required cognitive effort to comprehend interactive visual pictures and amplify cognition. Although the research on adaptive visualizations grew in the last years, the existing approaches do not consider the transformation pipeline from data to visual representation for a more efficient and effective adaptation. Further todays systems commonly require an initial training by experts from the field and are limited to adaptation based either on user behavior or on data characteristics. A combination of both is not proposed to our knowledge. This paper introduces an enhanced instantiation of our previously proposed model that combines both: involving different influencing factors for and adapting various levels of visual peculiarities, on content, visual layout, visual presentation, and visual interface. Based on data type and users' behavior, our system adapts a set of applicable visualization types. Moreover, retinal variables of each visualization type are adapted to meet individual or canonical requirements on both, data types and users' behavior. Our system does not require an initial expert modeling.

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Adaptive Visualization of Social Media Data for Policy Modeling

2014

Advances in Visual Computing. 10th International Symposium, ISVC 2014

International Symposium on Visual Computing (ISVC) <10, 2014, Las Vegas, NV, USA>

The visual analysis of social media data emerged a huge number of interactive visual representations that use different characteristics of the data to enable the process of information acquisition. The social data are used in the domain of policy modeling to gather information about citizens' demands, opinions, and requirements and help to decide about political policies. Although existing systems already provide a huge number of visual analysis tools, the search and exploration paradigm is not really clear. Furthermore, the systems commonly do not provide any kind of human centered adaptation for the different stakeholders involved in the policy making process. In this paper, we introduce a novel approach that investigates the exploration and search paradigm from two different perspectives and enables a visual adaptation to support the exploration and analysis process.

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Peter, Christian; Prophet, Heinrich; Haescher, Marian

AktiDia - Aktivitätsmessung in der Dialyse

2014

WOAR 2014

Workshop on Sensor-Based Activity Recognition (WOAR) <1, 2014, Rostock, Germany>

Im Rahmen der klinischen Studie AktiDia wurden Dialyse-Patienten mit verschiedenen Sensoren zur Erfassung der körperlichen Aktivität ausgestattet. Die Studie verfolgte drei Fragestellungen: zum einen wurde untersucht, wie verschiedene Aktivitätssensoren von Patienten angenommen werden und welche Eigenschaften ein Sensor für die Überwachung körperlicher Aktivität von Dialysepatienten haben sollte, um eine möglichst hohe Akzeptanz zu erlangen. Zweitens wurde das Aktivitätsverhalten von Dialysepatienten über einen Zeitraum von einer Woche untersucht, wobei insbesondere charakteristische Merkmale der Aktivitäten an Dialysetagen und den Tagen zwischen den Behandlungen betrachtet wurden sowie entsprechende Korrelationen zum Nachtschlaf der Patienten. Drittens wurde untersucht, ob und wie sich das Tragen eines Aktivitätssensors auf das Aktivitätsverhalten von Dialysepatienten auswirkt.

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Große-Puppendahl, Tobias; Beck, Sebastian; Wilbers, Daniel; Zeiß, Steeven; Wilmsdorff, Julian von; Kuijper, Arjan

Ambient Gesture-Recognizing Surfaces with Visual Feedback

2014

Distributed, Ambient, and Pervasive Interactions

International Conference on Distributed, Ambient and Pervasive Interactions (DAPI) <2, 2014, Heraklion, Crete, Greece>

In recent years, gesture-based interaction gained increasing interest in Ambient Intelligence. Especially the success of camera-based gesture recognition systems shows that a great variety of applications can benefit significantly from natural and intuitive interaction paradigms. Besides camera-based systems, proximity-sensing surfaces are especially suitable as an input modality for intelligent environments. They can be installed ubiquitously under any kind of non-conductive surface, such as a table. However, interaction barriers and the types of supported gestures are often not apparent to the user. In order to solve this problem, we investigate an approach which combines a semi-transparent capacitive proximity-sensing surface with an LED array. The LED array is used to indicate possible gestural movements and provide visual feedback on the current interaction status. A user study shows that our approach can enhance the user experience, especially for inexperienced users.

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Guest, Richard; Hurtado, Oscar Miguel; Henniger, Olaf

An Assessment of Methods for Image Recreation from Signature Time-series Data

2014

IET Biometrics

Human signatures are widely used for biometric authentication. For automatic on-line signature verification, rather than storing an image of the completed signature, data is represented in the form of a time-series of pen position and status information allowing the extraction of temporal-based features. For visualization purposes, signature images need to be recreated from time-series data. In this paper we investigate the accuracy and verification performance of a series of interpolation methods for recreating a signature image from time-series data contained in two ISO/IEC data storage formats. Our experiments investigate dynamic data stored at various sample rates and signature images recreated at differing resolutions. Our study indicates possible best practice in terms of image recreation method, recreated image resolution, and temporal sample rate and assesses the effect of on the accuracy of reconstructed signature data.

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Majewski, Martin; Dutz, Tim; Wichert, Reiner

An Optical Guiding System for Gesture Based Interactions in Smart Environments

2014

Distributed, Ambient, and Pervasive Interactions

International Conference on Distributed, Ambient and Pervasive Interactions (DAPI) <2, 2014, Heraklion, Crete, Greece>

Using gestures to control Ambient Intelligence environments can result in mismatches between the user's intention and the perception of the gesture by the system. One way to cope with this problem is to provide the user with an instant feedback on what the system has perceived. In this work, we present an approach for providing visual feedback to users of Ambient Intelligence systems that rely on gestures to control individual devices within their environments. This paper extends our previous work on this topic [1] and introduces several enhancements to the system.

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Anatomical Discovery: Finding Organs in the Neighborhood of the Liver

2014

XIII Mediterranean Conference on Medical and Biological Engineering and Computing

The Mediterranean Conference on Medical and Biological Engineering and Computing (MEDICON) <13, 2013, Seville, Spain>

Image segmentation and registration algorithms are fundamental to assist medical doctors for better treatment of the patients. To this end accuracy in the results given by those algorithms is crucial. The surroundings of the organ to be segmented or registered can provide additional information that at the end improves the result. In this paper a novel algorithm to detect the organs that surround the liver is introduced. Even though our work is focused on the liver, the algorithm could be extended to other parts of the body. The algorithm has been tested in 24 clinical CT datasets. In addition to this, an example application is introduced for which the detection is a useful tool.

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Alm, Rebekka; Waltemath, Dagmar; Wolkenauer, Olaf; Henkel, Ron

Annotation-Based Feature Extraction from Sets of SBML Models

2014

Data Integration in the Life Sciences

International Conference on Data Integration in the Life Sciences (DILS) <10, 2014, Lisbon, Portugal>

Model repositories such as BioModels Database provide computational models of biological systems for the scientific community. These models contain rich semantic annotations that link model entities to concepts in well-established bio-ontologies such as Gene Ontology. Consequently, thematically similar models are likely to share similar annotations. Based on this assumption, we argue that semantic annotations are a suitable tool to characterize sets of models. These characteristics can then help to classify models, to identify additional features for model retrieval tasks, or to enable the comparison of sets of models. In this paper, we present four methods for annotation-based feature extraction from model sets. All methods have been used with four different model sets in SBML format and taken from BioModels Database. To characterize each of these sets, we analyzed and extracted concepts from three frequently used ontologies for SBML models, namely Gene Ontology, ChEBI and SBO. We find that three of the four tested methods are suitable to determine characteristic features for model sets. The selected features vary depending on the underlying model set, and they are also specific to the chosen model set. We show that the identified features map on concepts that are higher up in the hierarchy of the ontologies than the concepts used for model annotations. Our analysis also reveals that the information content of concepts in ontologies and their usage for model annotation do not correlate.

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Braun, Andreas; Fellner, Dieter W. [Betreuer]; Mühlhäuser, Max [Referent]

Application and Validation of Capacitive Proximity Sensing Systems in Smart Environments

2014

Darmstadt, TU, Diss., 2014

Smart environments feature a number of computing and sensing devices that support occupants in performing their tasks. In the last decades there has been a multitude of advances in miniaturizing sensors and computers, while greatly increasing their performance. As a result new devices are introduced into our daily lives that have a plethora of functions. Gathering information about the occupants is fundamental in adapting the smart environment according to preference and situation. There is a large number of different sensing devices available that can provide information about the user. They include cameras, accelerometers, GPS, acoustic systems, or capacitive sensors. The latter use the properties of an electric field to sense presence and properties of conductive objects within range. They are commonly employed in finger-controlled touch screens that are present in billions of devices. A less common variety is the capacitive proximity sensor. It can detect the presence of the human body over a distance, providing interesting applications in smart environments. Choosing the right sensor technology is an important decision in designing a smart environment application. Apart from looking at previous use cases, this process can be supported by providing more formal methods. In this work I present a benchmarking model that is designed to support this decision process for applications in smart environments. Previous benchmarks for pervasive systems have been adapted towards sensors systems and include metrics that are specific for smart environments. Based on distinct sensor characteristics, different ratings are used as weighting factors in calculating a benchmarking score. The method is verified using popularity matching in two scientific databases. Additionally, there are extensions to cope with central tendency bias and normalization with regards to average feature rating. Four relevant application areas are identified by applying this benchmark to applications in smart environments and capacitive proximity sensors. They are indoor localization, smart appliances, physiological sensing and gesture interaction. Any application area has a set of challenges regarding the required sensor technology, layout of the systems, and processing that can be tackled using various new or improved methods. I will present a collection of existing and novel methods that support processing data generated by capacitive proximity sensors. These are in the areas of sparsely distributed sensors, model-driven fitting methods, heterogeneous sensor systems, image-based processing and physiological signal processing. To evaluate the feasibility of these methods, several prototypes have been created and tested for performance and usability. Six of them are presented in detail. Based on these evaluations and the knowledge generated in the design process, I am able to classify capacitive proximity sensing in smart environments. This classification consists of a comparison to other popular sensing technologies in smart environments, the major benefits of capacitive proximity sensors, and their limitations. In order to support parties interested in developing smart environment applications using capacitive proximity sensors, I present a set of guidelines that support the decision process from technology selection to choice of processing methods.

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Wacker, Fred; Urban, Bodo [Betreuer]; Bieber, Gerald [Betreuer]

Arbeitsgeräteidentifikation mittels Smartwatches

2014

Rostock, Univ., Diplomarbeit, 2014

In zahlreichen Branchen wie etwa der Forstwirtschaft, dem Straßenbau und der verarbeitenden Industrie werden motorisierte, handgeführte Arbeitsgeräte verwendet, die schädliche Vibrationen auf das Hand-Arm-System ihres Benutzers übertragen können. Langfristig kann dies zu gravierenden Gesundheitsschäden führen. Bisherige Überwachungstechnik zum Schutz vor Vibrationsbelastung ist kostenintensiv und erfordert in der Regel zusätzliche Arbeitsschritte. Diese Arbeit stellt ein Konzept zur automatischen Erkennung handgeführter Arbeitsgeräte durch handelsübliche Smartwatches vor. Dabei werden auf Basis der Daten von Beschleunigungssensor, Drehratensensor und Mikrofon Merkmale extrahiert, um durch Verfahren des maschinellen Lernens eine Differenzierung verschiedener Arbeitsgeräte untereinander sowie von Inaktivität zu ermöglichen. Als Nachweis der Umsetzbarkeit wurde mit 6 Arbeitsgeräten und 13 Probanden eine Evaluierung durchgeführt. Diese ergab, dass sich die Benutzung verschiedener Arbeitsgeräte unter den Versuchsbedingungen mit hoher Genauigkeit unterscheiden ließ. Grundsätzlich gelang dies auch anhand der Merkmale einzelner Sensoren. Die prototypische Implementierung gestattet eine Echtzeitüberwachung sowie eine langfristige Verfolgung der persönlichen Exposition gegenüber schädlichen Vibrationen. Durch eine semiautomatische Annotierung neuer Daten ist sie zudem in der Lage, auf einfache Weise um neue Arbeitsgeräte erweitert zu werden.

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Schader, Philipp; Kuijper, Arjan [Betreuer]; Steiger, Martin [2. Gutachter]

Assistiertes Energiemanagement durch Informationsvisualisierung

2014

Darmstadt, TU, Bachelor Thesis, 2014

Diese Arbeit beschreibt Konzepte zur Visualisierung von Energienetzen sowie zur Darstellung und Parametrisierung von Simulationen solcher. Es werden Darstellungen beschrieben mit denen sich ein Stromnetz darstellen lässt, sodass der Betriebszustand in dem es sich befindet zu erkennen ist. Weiter wird die Integration eines Simulators beschrieben mit dem Ziel ein interaktives System zu gestalten, welches durch die enge Verzahnung der Generierung und Darstellung von Daten, tiefe Einblicke in die Struktur des Versorgungsnetzes ermöglicht. Ein besonderes Augenmerk richtet sich hierbei auf die Möglichkeit die Simulationsergebnisse untereinander vergleichen zu können. Der im Rahmen dieser Arbeit entwickelte Prototyp verwendet die Konzepte auf Pegeldaten deutscher Wasserstraßen und zeigt so dass die Konzepte auch für allgemeine Sensornetzwerke verwendet werden können. Durch die Beschreibung eines konkreten Anwendungsfalls wird die Tauglichkeit der erarbeiteten Konzepte überprüft.

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Klamm, Christopher; Kuijper, Arjan [Betreuer]; Burkhardt, Dirk [Betreuer]

Ausprägungen elektronischer Beteiligung in Industrie- und Entwicklungsländern

2014

Darmstadt, TU, Bachelor Thesis, 2014

Partizipation ist ein etabliertes Element der partizipatorischen Demokratie. Immer wieder werden Mechanismen entwickelt, um Partizipation zu erhöhen und zu festigen. Mit Hilfe der voranschreitenden Entwicklung von Informations- und Kommunikationstechnologien, eröffnen sich neue Möglichkeiten von Partizipationsansätzen. Diese finden auch zunehmend weltweiten Einsatz. Neue partizipatorische Formen verwenden ICT als Mittel zur Unterstützung der Partizipation (E-Partizipation). In welche Bahnen E-Partizipation bereits gelenkt wurde ist Gegenstand dieser Arbeit. Sie setzt sich mit der Ausprägung vorhandener E-Partizipationsformen auseinander und betrachtet dabei anwendungsbezogene Projekte. Das Untersuchungsumfeld wurde dabei auf einen Ländervergleich festgelegt. Es handelt sich um einen Vergleich zwischen Deutschland, als repräsentatives Industrieland und Kenia, als Repräsentant für ein Entwicklungsland. Dafür wird, mit Hilfe einer historischen und anwendungsorientierten Betrachtung der E-Partizipation in den Ländern, ein Kontext aufgestellt. Mit dessen Hilfe werden die E-Partizipationsbestrebungen in Deutschland und Kenia anschließend mittels einer aufgestellten Klassifikation vergleichend gegenübergestellt. Die Analyse zeigt, dass deutsche Projekte vermehrt staatlich (Top-Down) initiiert sind, wo-hingegen in Kenia häufiger eine nicht-staatliche Ausrichtung (Ground-Up) existent ist. Weiterhin ist in kenianischen Projekten die Form "Transparenz durch Dritte" stärker ausgeprägt, in Deutschland ist es hingegen die konsultative Form. Im Bereich des fokussierten Bedürfnisses überwiegt in Deutschland die soziale Bedürfnisbefriedung, während in Kenia auch noch Sicherheitsbedürfnisse bedeutsam sind. Im Bereich der ICT-Form zeigt sich eine ähnliche Verteilung innerhalb der Länder bei den Formen Alert, FAQ und Forum. Partielle Unterschiede sind in den Formen Blog und Bewertung ausgeprägt, starke Differenzen existieren dagegen bei den Formen Chat, Umfrage und Spiel als Partizipationsmittel. Für letztere gilt, dass Chat und Umfrage nur in deutschen und das Spiel nur in kenianischen Projekten verwendet wurden.

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Mesing, Benjamin; Lukas, Uwe von

Authoring of Automatic Data Preparation and Scene Enrichment for Maritime Virtual Reality Applications

2014

Virtual Augmented and Mixed Reality. Applications of Virtual and Augmented Reality. Proceedings Part II

International Conference Virtual Augmented and Mixed Reality (VAMR) <6, 2014, Heraklion, Crete, Greece>

When realizing virtual reality scenarios for the maritime sector a key challenge is dealing with the huge amount of data. Adding interactive behaviour for providing a rich interactive experience manually requires a lot of time and effort. Additionally, even though shipyards today often use PDM or PLM systems to manage and aggregate the data, the export to a visualisation format is not without problems and often needs some post procession to take place. We present a framework that combines the capabilities of processing large amounts of data for preparing virtual reality scenarios and enriching it with dynamic aspects like interactive door opening capabilities. An authoring interface allows orchestrating the data preparation chain by non-expert users to realise individual scenarios easily.

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Vayanou, Maria; Katifori, Akrivi; Karvounis, Manos; Kourtis, Vassilis; Kyriakidi, Marialena; Roussou, Maria; Tsangaris, Manolis; Ioannidis, Yannis; Balet, Olivier; Prados, Thibaut; Keil, Jens; Engelke, Timo; Pujol, Laia

Authoring Personalized Interactive Museum Stories

2014

Interactive Storytelling

Joint International Conference on Interactive Digital Storytelling (ICIDS) <7, 2014, Singapore>

CHESS is a research prototype system aimed at enriching museum visits through personalized interactive storytelling. Aspiring to replace traditional exhibit-centric descriptions by story-centric cohesive narrations with carefully-designed references to the exhibits, CHESS follows a plot-based approach, where the story authors create stories around pre-selected museum themes. In this paper we place the CHESS system within the Interactive Digital Narrative field, describing the main objectives and requirements addressed. We present the system's architecture and outline its overall functionality. We describe the underlying storytelling model using examples from the stories authored using the CHESS Authoring Tool. Finally, we report key results focusing on the authors' perspective for the creation of personalized stories.

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Automated Kidney Detection and Segmentation in 3D Ultrasound

2014

Clinical Image-Based Procedures. Translational Research in Medical Imaging

International Workshop on Clinical Image-based Procedures (CLIP) <2, 2013, Nagoya, Japan>

Ultrasound provides the physical capabilities for a fast and save disease diagnosis in various medical scenarios including renal exams and patient trauma assessment. However, the experience of the ultrasound operator is the key element in performing ultrasound diagnosis. Thus, we like to introduce our automatic kidney detection and segmentation algorithm for 3D ultrasound. The approach utilizes basic kidney shape information to detect the kidney position. Following, the Level Set algorithm is applied to segment the detection result. In combination this method may help physicians and inexperienced trainees to achieve kidney detection and segmentation for diagnostic purposes.

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Automated Urban Management Processes: Integrating a Graphical Editor for Modular Domain-Specific Languages into a 3D GIS

2014

REAL CORP 2014. Plan it Smart. Clever Solutions for Smart Cities

International Conference on Urban Planning, Regional Development and Information Society <19, 2014, Vienna, Austria>

In this paper we present the results of integrating a graphical editor for geospatial processing workflows into a 3D GIS. We use modular domain-specific languages (DSLs) that are tailored to specific application domains. The vocabulary consists of so-called recipes that are grouped into cookbooks representing the language for a certain application domain. Recipes can be reused in multiple cookbooks. This approach allows for a good usability as the user quickly becomes familiar with the domain-specific languages by recognizing common recipes. In this paper we also describe guidelines for choosing the right granularity for recipes which allows for complex rules while using simplest possible recipes. We also describe a workflow for domain-specific language design based on ontologies to identify the correct domain vocabulary. Our approach can be used to automate processing of geospatial datasets in the area of urban planning. To evaluate our approach we use the implemented graphical rule editor in a practical scenario and present it to a user group from the urban API project.

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Brandherm, Florian; Kuijper, Arjan [Betreuer]; Limper, Max [Betreuer]

Automatic Appearance-Preserving Generation of Compact 3D Models for the Web

2014

Darmstadt, TU, Bachelor Thesis, 2014

The goal of this thesis was to create a fully automatic processing pipeline to simplify big arbitrary triangle meshes to a degree that can be used inside a web page using WebGL. While the mesh complexity is decreased by orders of magnitude, the original meshes details (e.g. colors, normals) are preserved by capturing them in textures. These textures can then be applied to the simplified mesh to give it an appearance that is similar in detail as the original high resolution mesh. The proposed implementation makes it easy to incorporate such a simplified mesh into a website by providing an exporter that generates a web site with all necessary files in suitable file formats. Simplified, detail-preserving 3D models are generated in multiple independent steps: First, the mesh is simplified with the quadric edge collapse algorithm[9]. Then, a texture atlas is created by segmenting the simplified mesh and parameterizing the individual segments with Least Squares Conformal Maps[14]. After packing the individual segments into a texture atlas, the details of the high-resolution input mesh are captured in textures. At the end of this processing pipeline, the model is exported. The results show that the goal of creating file sizes that are small enough for a web page while preserving a reasonable amount of detail was reached. It is shown that the resulting files can compete with the alternative approach of creating interactive 3Dvisualizations with a series of pre-rendered images. The analysis of the results also shows that there is a lot of potential to increase the file size to detail ratio further.

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Knöbelreiter, Patrick; Berndt, René; Ullrich, Torsten; Fellner, Dieter W.

Automatic Fly-through Camera Animations for 3D Architectural Repositories

2014

GRAPP 2014

International Conference on Computer Graphics Theory and Applications (GRAPP) <9, 2014, Lisbon, Portugal>

Virtual fly-through animations through computer generated models are a strong tool to convey properties and the appearance of these models. In, e.g., architectural models the big advantage of such a fly-through animation is that it is possible to convey the structure of the model easily. However, the path generation is not always trivial, to get a good looking animation. The proposed approach in this paper can handle arbitrary 3D models and then extract a meaningful and good looking camera path. To visualize the path HTML/X3DOM is used and therefore it is possible to view the final result in a browser with X3DOM support.

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Romann, René; Bieber, Gerald; Salomon, Ralf

Automatische Tremorerkennung mittels Smartphones und intelligenter Uhren

2014

WOAR 2014

Workshop on Sensor-Based Activity Recognition (WOAR) <1, 2014, Rostock, Germany>

Dieser Tremor ist an und für sich nichts Schlimmes und ist bei allen Menschen vorhanden und beobachtbar. Doch kann ein verstärkter Tremor als Folge anderer Krankheitsbilder wie beispielsweise Parkinson oder in Folge körperlicher Extremzustände wie Unterzuckerung, Unterkühlung oder Stress auftreten und somit als Indikator für selbige dienen. Gegenwärtig wird die Tremorbestimmung ambulant im Krankenhaus durchgeführt, was für Patienten und Ärzte mit signifikantem Aufwand und somit hohen Kosten für das Gesundheitswesen verbunden ist. In diesem Beitrag wird untersucht, inwiefern sich der Tremor auch mit handelsüblichen Geräten wie Smartphones und Smartwatches vom Patienten selbstständig bestimmen lässt. Die durchgeführten Experimente weisen darauf hin, dass dies mit den Geräten der neusten Generation in vielen Fällen einfach und zuverlässig möglich ist.

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Neumann, Stephan; Kuijper, Arjan [Betreuer]; Braun, Andreas [Betreuer]

Automotive Interfaces Using an Interactive Armrest

2014

Darmstadt, TU, Bachelor Thesis, 2014

Due to the rapid technological development of cars and their entertainment and infotainment systems, drivers are confronted with feature-rich interfaces that can become both confusing and distracting. Therefore, new ways of interaction between driver and car have to be developed in order to reduce driver distraction to a minimum. This is relevant to the safety of both the driver and road users surrounding him. In this thesis, gesture based interaction in the automotive is examined. The main focus is gestural interaction using capacitive sensors. In this area, an overview over related work is given. Challenges in developing a capacitive system for gesture based interaction in the automotive environment are presented and discussed. Afterwards, a model for a gesture-based input system using an augmented armrest is proposed. A prototypical system is implemented in order to test the possibilities and limitations of the proposed model. This system is then evaluated in order to test its general viability and to compare different kinds of gestures for interacting with in-car systems.

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Damer, Naser; Opel, Alexander; Nouak, Alexander

Biometric Source Weighting in Multi-Biometric Fusion: Towards a Generalized and Robust Solution

2014

2014 Proceedings of the 22nd European Signal Processing Conference (EUSIPCO)

European Signal Processing Conference (EUSIPCO) <22, 2014, Lisbon, Portugal>

This work presents a new weighting algorithm for biometric sources within a score-level multi-biometric system. Those weights are used in the effective and widely used weighted sum fusion rule to produce multi-biometric decisions. The presented solution is mainly based on the characteristic of the overlap region between the genuine and imposter scores distributions. It also integrates the performance of the biometric source represented by its equal error rate. This solution aims at avoiding the shortcomings of previously proposed solutions such as low generalization abilities and sensitiveness to outliers. The proposed solution is evaluated along with the state of the art and best practice techniques. The evaluation was performed on two databases, the Biometric Scores Set BSSR1 and the Extended Multi Modal Verification for Teleservices and Security applications database and a satisfying and stable performance was achieved.

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Nouak, Alexander

Biometrie: Technik, Mythen, Praxisbeispiele

2014

BvD-News

Unter dem Begriff Biometrie ist das automatische Erkennen von Individuen anhand deren Verhalten und ihrer biologischen Charakteristika zu verstehen. In einer zunehmend technisierten Welt kann sie immer dann zum Einsatz kommen, wenn es darum geht, personengebundene Zugriffs- oder Zutrittsberechtigungen zu prüfen. Das kann der Zutritt zur eigenen Wohnung genauso sein wie die Einreise in einen fremden Staat. Zahlreiche Mythen ranken um diese Technologie: Sie sei für erhöhte Sicherheit geeignet, diene der Überwachung, ließe sich leicht durch Fälschungen umgehen und würde die Überwachung befördern. Diese Mythen schürten in der Vergangenheit auch eine gehörige Portion Angst, nicht zuletzt allein deshalb, weil ihre Funktionsweise nicht wirklich bekannt ist. Dieser Artikel will mit den größten Missverständnissen aufräumen.

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Brömme, Arslan [Ed.]; Busch, Christoph [Betreuer]

BIOSIG 2014

2014

Annual International Conference of the Biometrics Special Interest Group (BIOSIG) <13, 2014, Darmstadt, Germany>

GI-Edition - Lecture Notes in Informatics (LNI)

Biometrics provides efficient and reliable solutions to recognize individuals. With increasing number of identity theft and misuse incidents we do observe a significant fraud in e-commerce and thus growing interests on trustworthiness of person authentication. Nowadays we find biometric applications in areas like border control, national ID cards, e-banking, e-commerce, e-health etc. Large-scale applications such as the European Union Visa Information System (VIS) and Unique Identification (UID) in India require high accuracy and also reliability, interoperability, scalability, system reliability and usability. Many of these are joint requirements also for forensic applications. Multimodal biometrics combined with fusion techniques can improve recognition performance. Efficient searching or indexing methods can accelerate identification efficiency. Additionally, quality of captured biometric samples can strongly influence the performance. BIOSIG 2014 offers you once again a platform for international experts' discussions on biometrics research and the full range of security applications.

  • 978-3-88579-624-4
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Steger, Teena; Fellner, Dieter W. [Betreuer]; Sakas, Georgios [Referent]; Wagner, Manfred [Referent]

Bronchoskopische Navigation mittels Pose Estimation des C-Bogens aus musterkodierten Fluoroskopie-Aufnahmen

2014

Darmstadt, TU, Diss., 2014

Die Bronchoskopie ist die wichtigste und sicherste Untersuchungsmethode bei Verdacht auf Lungenkrebs. Sie dient sowohl der visuellen Inspektion der Atemwege als auch der Gewebeentnahme an verdächtigen Läsionen. Erst aufgrund der so gewonnenen Probe kann entschieden werden, ob es sich um bösartiges Gewebe handelt. Damit die Biopsie an der korrekten Stelle durchgeführt wird, ist es besonders wichtig, dass die bronchoskopischen Operationsinstrumente präzise innerhalb des Bronchialbaums geführt werden können. Dabei behilft sich der Arzt zum einen mit der Kamera an der Bronchoskopspitze und zum anderen mit der intraoperativen C-Bogen-Durchleuchtung. Leider liefert keine dieser Visualisierungstechniken eine 3D-Sicht des Bronchialbaums oder die aktuelle 3D-Position des Instruments. Genau diese Hilfestellung leisten bronchoskopische Navigationssysteme und tragen somit erheblich zur Genauigkeit der Instrumentenführung und Beschleunigung des Eingriffs bei. Bronchoskopische Navigationssysteme verwenden meist EM-Sensoren, um die aktuelle Position des Instruments innerhalb der Bronchien zu verfolgen. Solche Systeme müssen nicht nur kostspielig und aufwändig installiert, sondern die jeweiligen getrackten Instrumente auch nach jedem Gebrauch teuer ersetzt werden. Um dieses Problem zu umgehen, wird auch an Systemen entwickelt, die lediglich die Bronchoskopvideobilder zur 2D/3D-Registrierung verwenden. Damit kann die Navigation aber nur so lange angeboten werden, wie die Bronchoskopspitze in die Bronchien vorgeschoben werden kann. Im Normalfall wird aber gerade in den nicht erreichbaren peripheren Verästelungen eine Navigationsstütze benötigt. Deshalb wird in dieser Arbeit ein Verfahren vorgestellt, welches unabhängig von der Bronchoskopreichweite anwendbar ist und ausschließlich auf die bereits vorhandene Ausstattung im OP-Saal zurückgreift. Somit wird eine höhere klinische Einsetzbarkeit und Akzeptanz erwartet. Die neuartige Grundidee ist hierbei, dass bei bekannter Aufnahmeposition des C-Bogens ein virtueller Strahl von C-Bogen-Röntgenquelle durch das Patienten-CT zur Instrumentenspitzenposition auf dem Durchleuchtungsbild generiert werden kann. Dieser 3D-Strahl schneidet dann den Bronchialbaum im CT genau an der Stelle, wo sich das Instrument aktuell befindet. Die große Herausforderung ist nun die C-Bogen Pose während der Aufnahme zu bestimmen. Dafür wurde von mir eine innovative Markerplatte entwickelt, die auf dem Patiententisch befestigt wird. Bei jeder Aufnahme wird ein Teil der radioopaken Marker auf der Durchleuchtung abgebildet. Um nun eine C-Bogen Pose Estimation durchzuführen, müssen die abgebildeten 2D-Marker eindeutig ihren korrespondierenden 3D-Markern auf der Platte zugeordnet werden. Deshalb habe ich bei der Anordnung der Marker erstmals die projektive Invariante Doppelverhältnis eingesetzt. Dies ermöglicht, dass die Marker auch nach Projektion verlässlich identifiziert und zugeordnet werden. Die entworfene Markerplatte wurde zahlreichen Experimenten unterzogen, darunter auch Phantom- und Tierkadavertests. Dabei wurden sehr gute quantitative Ergebnisse für die C-Bogen Pose Estimation bezüglich Erfolgsraten und Genauigkeiten gemessen. In dieser Arbeit stellt weitere wichtige Komponenten eines Bronchoskopie-Navigationssystems vor: Bronchialbaumsegmentierung und -skeletonisierung, Tumorsegmentierung, 2D-Instrumentenverfolgung, Patient-zu-Tisch-Registrierung, Pfadberechnung und 3D-Visualisierung. Dabei wurden vorhandene Lösungen aus der Literatur aufgegriffen bzw. erweitert aber auch neue Methoden entwickelt. Alle diese Komponenten wurden sowohl einzeln und als auch im Zusammenspiel miteinander untersucht. Bei Tests mit einem Bronchialbaumphantom erzielte sehr gute qualitative Ergebnisse..

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Tazari, Mohammad-Reza; Wichert, Reiner

Can the Market Breakthrough in AAL Be Provided by a Large Scale Pilot?

2014

Ambient Assisted Living

Ambient Assisted Living (AAL) <6, 2013, Berlin, Germany>

Ambient Assisted Living is still on the cusp of a mainstream breakthrough, even though the market potential is tremendous. As barriers to the success of AAL, [1] mentions the lack of viable business models as well as the lack of ecosystems around common open platforms. Considering the fact that the EU has supported the development of universAAL as a true candidate for such common open platforms, this paper describes the next logical step towards the rollout of AAL throughout Europe based on this platform so that the foundation stone for the emergence of a self-organizing ecosystem is laid. In order to elaborate the feasibility of such rollouts, the European Commission published in early 2012 a CIP-ICT-PSP call for piloting AAL in large-scale based on interoperable platforms, where the winner was the proposal "make it ReAAL" that builds on universAAL as the common open platform. In addition to the applications coming with the universAAL Platform, the local vendors from each pilot region will offer their AAL products and services to the participating pilot sites. This means that a two-way adaptation is supposed to be addressed in ReAAL: on one hand, the universAAL native applications can be adapted to the requirements of the pilot sites, and on the other hand, the existing applications from the pilot regions can be integrated with the universAAL platform. Each Pilot site will then be able to select from this portfolio, those applications that are more suitable for their planned intervention. The mission of ReAAL is in this context to find out if the adaptation of a product to a common platform is economically reasonable when a company plans to enter the market with a new product idea. Based on this, ReAAL will hopefully show the cost-effectiveness of interoperable solutions compared to both vertical isolated solutions and comprehensive but closed systems. This should pave the way for the emergence of an ecosystem around a common open platform and based on that for the market breakthrough of AAL through interoperability.

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Große-Puppendahl, Tobias; Herber, Sebastian; Wimmer, Raphael; Englert, Frank; Beck, Sebastian; Wilmsdorff, Julian von; Wichert, Reiner; Kuijper, Arjan

Capacitive Near-Field Communication for Ubiquitous Interaction and Perception

2014

UbiComp' 14

International Conference on Ubiquitous Computing (Ubicomp) <16, 2014, Seattle, WA, USA>

Smart objects within instrumented environments offer an always available and intuitive way of interacting with a system. Connecting these objects to other objects in range or even to smartphones and computers, enables substantially innovative interaction and sensing approaches. In this paper, we investigate the concept of Capacitive Near-Field Communication to enable ubiquitous interaction with everyday objects in a short-range spatial context. Our central contribution is a generic framework describing and evaluating this communication method in Ubiquitous Computing. We prove the relevance of our approach by an open-source implementation of a low-cost object tag and a transceiver offering a high-quality communication link at typical distances up to 15 cm. Moreover, we present three case studies considering tangible interaction for the visually impaired, natural interaction with everyday objects, and sleeping behavior analysis.

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Frank, Sebastian; Braun, Andreas [Betreuer]

Capacitive Proximity Sensing Supported Advanced Driver Assistance System

2014

Rüsselsheim, Hochschule RheinMain, Master Thesis, 2014

This work's general topic is advanced driver assistance systems. In particular, it's about the assisted driver seat adjustment in dependence on anthropometric data, the detection of Out-of-Position postures and the driver drowsiness detection. Already existing systems use sensors like in- and off-cabin cameras to detect drowsiness or require the manual input of anthropometric data to adjust the driver's seat. Contrary to these system's approaches, the aim of this work is to build a system which captures drowsiness symptoms, tracks the head position and captures anthropometric data only by the use of invisible seat integrated capacitive proximity sensors. Still, the aim includes the evaluation of the system's concepts to give direction for further examinations. The idea is the integration of several capacitive proximity sensors at meaningful positions into a driver's seat. Owing to the fact that these sensors can sense through non-conductive materials, the sensors can be installed invisible under the seat cover. Furthermore, the sensors measure changes in the electric field. Occupants, which are in range of the sensors, change the electric field. Therefore, the sensor values shall give information about the occupant's anthropometry and position. With these anthropometric data, an assisted seat adjustment shall be possible. Especially the movement of the driver's head could give information about the driver's drowsiness. A first question of this report addresses the driver's anthropometry. What's a proper seat adjustment? Furthermore, what are the symptoms for drowsiness and which could be measured with capacitive proximity sensors? Moreover, what is an Out-of-Position posture? With information about the anthropometrical requirements, the work shows which concepts can meet the demands on the system. Owing to the fact that the system needs evaluation, how shall a prototype be developed with reference to the concepts? Due to the results of the evaluation, the concepts can satisfy the demands on the system. The ideas which rely on machine learning classifiers result in reliable data. Nevertheless, the different approaches show different demands on the collected data's diversity, which is used to train the algorithms. Besides the machine learning classifiers, many functions of the assisted seat adjustment depend on generic relations between the prototype's sensor system and the occupant's anthropometry. These functions show positive results. Nevertheless, a multiclass SVM approach with discrete adjustment classification could lead to better results, because this approach can include more sensors. Therefore, further obedience between the sensors' data and the anthropometry could be included. Several functions of advanced driver assistance systems are integrated into the capacitive proximity sensing supported advanced driver assistance system. The evaluation shows that invisibly seat integrated capacitive proximity sensors can sense several symptoms of driver drowsiness. Furthermore, the system can assist the driver's seat adjustment and detect "Out-of-Position" postures. The detection concepts are constrained by several requirements for a proper working system. Consequently, the next step is a further integration of the system into a real car. Supplementary, the evaluation shows that the machine learning concepts require a plenty of miscellaneous data. Hence, a further data collection will improve the systems creditableness. Besides the further data collection and real system integration, the developed prototype can be the basis for a further function development, like the gesture recognition for the control of a multimedia system.

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Katifori, Akrivi; Karvounis, Manos; Kourtis, Vassilis; Kyriakidi, Marialena; Roussou, Maria; Tsangaris, Manolis; Vayanou, Maria; Ioannidis, Yannis; Balet, Olivier; Prados, Thibaut; Keil, Jens; Engelke, Timo; Pujol, Laia

CHESS: Personalized Storytelling Experiences in Museums

2014

Interactive Storytelling

Joint International Conference on Interactive Digital Storytelling (ICIDS) <7, 2014, Singapore>

In this work, we present the CHESS research prototype system which offers personalized, interactive digital storytelling experiences to enhance museum visits, demonstrating the authoring and visiting experiences.

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Erdt, Marius [Ed.]; Linguraru, Marius George [Ed.]; Oyarzun Laura, Cristina [Betreuer]; Shekhar, Raj [Ed.]; Wesarg, Stefan [Betreuer]; González Ballester, Miguel Angel [Ed.]; Drechsler, Klaus [Betreuer]

Clinical Image-Based Procedures. Translational Research in Medical Imaging

2014

International Workshop on Clinical Image-based Procedures (CLIP) <2, 2013, Nagoya, Japan>

Lecture Notes in Computer Science (LNCS)

This book constitutes revised selected papers from the International Workshop on Clinical Image-Based Procedures, CLIP 2013, held in conjunction with MICCAI 2012 in Nagoya, Japan, in September 2013. The 19 papers presented in this volume were carefully reviewed and selected from 26 submissions. The workshop was a productive and exciting forum for the discussion and dissemination of clinically tested, state-of-the-art methods for image-based planning, monitoring and evaluation of medical procedures.

  • 978-3-319-05665-4
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Linguraru, Marius George [Ed.]; Oyarzun Laura, Cristina [Betreuer]; Shekhar, Raj [Ed.]; Wesarg, Stefan [Betreuer]; González Ballester, Miguel Angel [Ed.]; Drechsler, Klaus [Betreuer]; Sato, Yoshinobu [Ed.]; Erdt, Marius [Ed.]

Clinical Image-Based Procedures. Translational Research in Medical Imaging

2014

International Workshop on Clinical Image-based Procedures (CLIP) <3, 2014, Boston, MA, USA>

Lecture Notes in Computer Science (LNCS)

CLIP 2014 provided a successful forum for the dissemination of emerging image-based clinical techniques. Specific topics included pre-interventional image segmentation and classification (to support diagnosis and clinical decision making), interventional and surgical planning and analysis of dynamic images, and evaluation, visualization and correction techniques for image-based procedures. Clinical applications covered the skull and the brain, cardiac defects, blood vessels, abdominal organs, and cancer in adults and children. The presentations and discussions around the meeting emphasized current challenges and emerging techniques in image-based procedures, strategies for clinical translation of image-based techniques, the role of computational anatomy and image analysis for surgical planning and interventions, and the contribution of medical image analysis to open and minimally invasive surgery.

  • 978-3-319-13908-1
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Hadjiprocopis, Andreas; Wenzel, Konrad; Rothermel, Mathias; Ioannides, Marinos; Fritsch, Dieter; Klein, Michael; Johnsons, Paul S.; Weinlinger, Guenther; Doulamis, Anastasios; Protopapadakis, Eftychios; Kyriakaki, Georgia; Makantasis, Kostas; Fellner, Dieter W.; Stork, André; Santos, Pedro

Cloud-based 3D Reconstruction of Cultural Heritage Monuments using Open Access Image Repositories

2014

GCH 2014. Short Papers - Posters

Eurographics Symposium on Graphics and Cultural Heritage (GCH) <12, 2014, Darmstadt, Germany>

A large number of photographs of cultural heritage items and monuments is publicly available in various Open Access Image Repositories (OAIR) and social media sites. Metadata inserted by camera, user and host site may help to determine the photograph content, geo-location and date of capture, thus allowing us, with relative success, to localise photos in space and time. Additionally, developments in Photogrammetry and Computer Vision, such as Structure from Motion (SfM), provide a simple and cost-effective method of generating relatively accurate camera orientations and sparse and dense 3D point clouds from 2D images. Our main goal is to provide a software tool able to run on desktop or cluster computers or as a back end of a cloud-based service, enabling historians, architects, archaeologists and the general public to search, download and reconstruct 3D point clouds of historical monuments from hundreds of images from the web in a cost-effective manner. The end products can be further enriched with metadata and published. This paper describes a workflow for searching and retrieving photographs of historical monuments from OAIR, such as Flickr and Picasa, and using them to build dense point clouds using SfM and dense image matching techniques. Computational efficiency is improved by a technique which reduces image matching time by using an image connectivity prior derived from low-resolution versions of the original images. Benchmarks for two large datasets showing the respective efficiency gains are presented.

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Damer, Naser; Opel, Alexander; Nouak, Alexander

CMC Curve Properties and Biometric Source Weighting in Multi-Biometric Score-level Fusion

2014

FUSION 2014

International Conference on Information Fusion (FUSION) <17, 2014, Salamanca, Spain>

Multi-biometrics tries to build a unified biometric decision based on multiple biometric sources in an effort to gain more accuracy and robustness. Multi-biometric fusion aims at optimally combining the information produced by the multiple biometric sources, this usually requires assigning relative weights for the biometric sources to optimize their effect on the final decision. This work presents a new approach for biometric sources weighting within a score-level multi-biometric system. The presented solution tries to investigate the properties of the cumulative match characteristic (CMC) curve, which represents the biometric performance under the identification scenario, and extract biometric source weights based on those properties. The proposed solution is evaluated along with a set of state of the art and best practice weighting techniques. The evaluation was performed on the Biometric Scores Set BSSR1 database and a satisfying and stable performance was achieved.

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Daun, Kevin; Weber, Daniel [Betreuer]

Collision Handling between Rigid and Deformable Bodies with Continuous Penalty Forces

2014

Darmstadt, TU, Bachelor Thesis, 2014

Collision handling has been an active research topic in the area of the physically-based simulation of rigid and deformable bodies for many years. A common approach in interactive environments are discrete penalty forces, computing a repulsion forced based on the penetration at one moment in the time step. They provide low computational costs and good scalability, though they suffer from jitter and instability. Tang et al. [18] improved the approach of discrete penalty forces and introduced 2012 the continuous penalty forces, continuously accumulating penalty forces along the penetration trajectory over the whole time step. Thereby, the jitter and instability issues are reduced. Although, the continuous penalty forces show artifacts especially for enduring contacts, precluding the simulation of sliding contacts. In this thesis, we present a unified system to handle collisions between rigid and deformable bodies with friction. We modify the integration scheme by Bridson et al. [4] to handle rigid and deformable bodies, apply a continuous collision detection [16], handle the detected collisions with continuous penalty forces [18] and apply a penalty-based friction model [23]. We discuss the artifacts arising from the continuous penalty forces algorithm, examine methods to tackle them and apply the new methods to the continuous penalty forces algorithm. Finally, we analyze the results of the continuous penalty forces algorithm in comparison to discrete penalty forces, evaluate our new algorithm to handle the continuous penalty forces artifacts and inspect further improvements.

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Preiss, Jens; Fernandes, Felipe; Urban, Philipp

Color-Image Quality Assessment: From Prediction to Optimization

2014

IEEE Transactions on Image Processing

While image-difference metrics show good prediction performance on visual data, they often yield artifact-contaminated results if used as objective functions for optimizing complex image-processing tasks. We investigate in this regard the recently proposed color-image-difference (CID) metric particularly developed for predicting gamut-mapping distortions. We present an algorithm for optimizing gamut mapping employing the CID metric as the objective function. Resulting images contain various visual artifacts, which are addressed by multiple modifications yielding the improved color-image-difference (iCID) metric. The iCID-based optimizations are free from artifacts and retain contrast, structure, and color of the original image to a great extent. Furthermore, the prediction performance on visual data is improved by the modifications.

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Samadzadegan, Sepideh; Blahová, Jana; Urban, Philipp

Color-Printed Gloss: Relating Measurements to Perception

2014

22nd Color and Imaging Conference. Final Program and Proceedings

Color and Imaging Conference (CIC) <22, 2014, Boston, MA, USA>

In order to assess the print quality, color and gloss are two important factors that should always be considered. In this paper, we investigate the impact of color on gloss using printed color samples varying between low and medium gloss levels. A psychophysical experiment was conducted to relate specular gloss measurements to perception. Results show that second order polynomials describe well this relationship independently of the underlying color. Following the same trend for all colors, the magnitude of perceived gloss decreases with increasing lightness.

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Combining Computational Models and Interactive Visualization to Support Rational Decision Making

2014

Advances in Visual Computing. 10th International Symposium, ISVC 2014

International Symposium on Visual Computing (ISVC) <10, 2014, Las Vegas, NV, USA>

Decision making is a complex process consisting of several consecutive steps. Before converting a decision into effective action the problem to be tackled needs to be analyzed, alternative solutions need to be developed, and the best solution needs to be picked. In many cases computational models support decision makers in this process. Therefore, providing an intuitive access to these model-driven techniques is crucial. In this approach, we introduce a decision support system that provides visual-interactive access to three computational models - a simulation model, an optimization model, and an opinion mining model - covering different aspects of decision making. For each model our decision support system realizes the visual access to the model, an in-depth analysis of the generated solutions, and the comparison of alternative solutions. Finally, we evaluate the usefulness and the usability of our system in a use case in the field of public policy making.

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Comparison of e-Participation Roadmap in Industrial and Developing Countries based on Germany and Kenya

2014

ICEGOV 2014

International Conference on Theory and Practice of Electronic Governance (ICEGOV) <8, 2014, Guimaraes, Portugal>

This paper compares the E-Participation roadmaps of industrial and developing countries, based on Germany and Kenya as representatives. Therefore, the ICT roadmap of each country is de-scribed in a clear shape and with representative E-Participation projects of each country. Based on these projects, the comparison is performed on a categorical level in terms of (1) participation forms, (2) used ICT, and (3) socio-political requirements. After-wards, the results are summarized to determine an overall view on the E-Participation situation in both countries. As a result of the comparison similarities and significant differences will be identified. The results are useful for software developing organizations that want to create ICT governance tools for industrial as well as developing countries and therefore need to consider the characteristics and requirements of both country types.

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Edelsbrunner, Johannes; Krispel, Ulrich; Havemann, Sven; Sourin, Alexei; Fellner, Dieter W.

Constructive Roof Geometry

2014

2014 International Conference on Cyberworlds

International Conference on Cyberworlds (CW) <13, 2014, Santander, Spain>

While the growing demand for new building models contained in virtual worlds, games, and movies, makes the easy and fast creation of modifiable models more and more important, 3D modeling of buildings can be a tedious task due to their sometimes complex geometry. For historic buildings, especially the roofs can be challenging. We present a new method of combining simple building solids to form more complex buildings, and give an emphasis on the blending of roof faces. This can be integrated in common pipelines for procedural modeling of buildings and will bring more expressiveness than existing methods.

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Grabner, Harald; Ullrich, Torsten; Fellner, Dieter W.

Content-based Retrieval of 3D Models using Generative Modeling Techniques

2014

GCH 2014. Short Papers - Posters

Eurographics Symposium on Graphics and Cultural Heritage (GCH) <12, 2014, Darmstadt, Germany>

In this paper we present a novel 3D model retrieval approach based on generative modeling techniques. In our approach generative models are created by domain experts in order to describe 3D model classes. These generative models span a shape space, of which a number of training samples is taken at random. The samples are used to train content-based retrieval methods. With a trained classifier, techniques based on semantic enrichment can be used to index a repository. Furthermore, as our method uses solely generative 3D models in the training phase, it eliminates the cold start problem. We demonstrate the effectiveness of our method by testing it against the Princeton shape benchmark.

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Gutzeit, Enrico; Scheel, Christian; Dolereit, Tim; Rust, Matthias

Contour Based Split and Merge Segmentation and Pre-classification of Zooplankton in Very Large Images

2014

VISAPP 2014 - Volume I

International Conference on Computer Vision Theory and Applications (VISAPP) <9, 2014, Lisbon, Portugal>

Zooplankton is an important component in the water ecosystem and food chain. To understand the influence of zooplankton on the ecosystem a data collection is necessary. In research the automatic image based recognition of zooplankton is of growing interest. Several systems have been developed for zooplankton recognition on low resolution images. For large images approaches are seldom. Images of this size easily exceed the main memory of standard computers. Our novel automatic segmentation approach is able to handle these large images. We developed a contour based Split & Merge approach for segmentation and, to reduce the nonzooplankton segments, combine it with a pre-classification of the segments in reference to their shape. The latter includes a detection of quasi round segments and a novel one for thin segments. Experimental results on several large images show that we are able to handle them satisfactorily.

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Controlling the Processing of Smart City Data in the Cloud with Domain-Specific Languages

2014

2014 IEEE/ACM 7th International Conference on Utility and Cloud Computing

International Conference on Utility and Cloud Computing (UCC) <7, 2014, London, England, United Kingdom>

In this paper a new user interface for the processing of big geospatial data in the Cloud is presented. The paper focuses on the processing of Smart City data since this kind of data is inherently large and becomes more and more important for the maintenance and planning of sustainable future Smart Cities. The user interface is facilitated by Domain-Specific Languages (DSLs) that are tailored to the urban planning domain. In this paper a modelling method for DSLs is described and then applied to an example use case from the research project IQmulus funded by the European Commission. The resulting DSL is specified using a Parsing Expression Grammar (PEG) which is used to automatically generate a language parser. Furthermore, a technique to interpret scripts written in the Domain-Specific Language is presented. This technique makes use of mapping rules that specify how the interpreter has to translate terms in the DSL to processing services in the Cloud.

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Converting Underwater Imaging into Imaging in Air

2014

VISAPP 2014 - Volume I

International Conference on Computer Vision Theory and Applications (VISAPP) <9, 2014, Lisbon, Portugal>

The application of imaging devices in underwater environments has become a common practice. Protecting the camera's constituent electric parts against water leads to refractive effects emanating from the water-glassair transition of light rays. These non-linear distortions can not be modeled by the pinhole camera model. For our new approach we focus on flat interface systems. By handling refractive effects properly, we are able to convert the problem to imaging conditions in air. We show that based on the location of virtual object points in water, virtual parameters of a camera following the pinhole camera model can be computed per image ray. This enables us to image the same object as if it was situated in air. Our novel approach works for an arbitrary camera orientation to the refractive interface. We show experimentally that our adopted physical methods can be used for the computation of 3D object points by a stereo camera system with much higher precision than with a naive in-situ calibration.

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Becker, Tilman; Burghart, Catherina; Nazemi, Kawa; Ndjiki-Nya, Patrick; Riegel, Thomas; Schäfer, Ralf; Sporer, Thomas; Tresp, Volker; Wissmann, Jens

Core Technologies for the Internet of Services

2014

Towards the Internet of Services: The THESEUS Research Program

Information and knowledge are growing permanently and represent valuable resources for many enterprises. The efficient access to knowledge of an enterprise like expertise, contact persons, project and milestone plans, etc. may simplify business processes and lead to time and cost savings. Semantic technologies offer numerous possibilities to enrich data with background information about their meaning. Such semantic relations do not only lead to more efficient search in larger information repositories but they also assist the user in diverse processes like editing, annotation, and processing of information. In addition they offer new means of access and transfer of knowledge. Each information unit is linked to other units in the same domain, which allows faster search and offers a way of information access that is close to the habits of humans, i.e. the creation of knowledge and its association to already existing knowledge. This approach of the whole THESEUS research program was also the basis of the CORE TECHNOLOGY CLUSTER of THESEUS.

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Jung, Florian; Steger, Sebastian; Knapp, Oliver; Noll, Matthias; Wesarg, Stefan

COSMO - Coupled Shape Model for Radiation Therapy Planning of Head and Neck Cancer

2014

Clinical Image-Based Procedures. Translational Research in Medical Imaging

International Workshop on Clinical Image-based Procedures (CLIP) <3, 2014, Boston, MA, USA>

Radiation therapy plays a major role in head and neck cancer treatment. Segmentation of organs at risk prior to the radiation therapy helps to prevent the radiation beam from damaging healthy tissue, whereas a concentrated ray can target the cancerous regions. Unfortunately, the manual annotation of all relevant structures in the head and neck area is very time-consuming and existing atlas-based solutions don't provide sufficient segmentation accuracy. Therefore, we propose a coupled shape model (CoSMo) for the segmentation of key structures within the head and neck area. The model's adaptation to a test image is done with respect to the appearance of its items and the trained articulation space. 40 data sets labeled by clinicians containing 22 structures were used to build the CoSMo. Even on very challenging data sets with unnatural postures, which occur far more often than expected, the model adaptation algorithm succeeds. A first evaluation showed an average directed Hausdorff distance of 13.22mm and an average DICE overlap of 0.62. Furthermore, we review some of the challenges we encountered during the course of building our model from image data, taken from actual radiation therapy planing cases.

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Santos, Pedro; Ritz, Martin; Tausch, Reimar; Schmedt, Hendrik; Monroy Rodriguez, Rafael; Stefano, Antonio; Posniak, Oliver; Fuhrmann, Constanze; Fellner, Dieter W.

CultLab3D - On the Verge of 3D Mass Digitization

2014

GCH 2014

Eurographics Symposium on Graphics and Cultural Heritage (GCH) <12, 2014, Darmstadt, Germany>

Acquisition of 3D geometry, texture and optical material properties of real objects still consumes a considerable amount of time, and forces humans to dedicate their full attention to this process. We propose CultLab3D, an automatic modular 3D digitization pipeline, aiming for efficient mass digitization of 3D geometry, texture, and optical material properties. CultLab3D requires minimal human intervention and reduces processing time to a fraction of today's efforts for manual digitization. The final step in our digitization workflow involves the integration of the digital object into enduring 3D Cultural Heritage Collections together with the available semantic information related to the object. In addition, a software tool facilitates virtual, location-independent analysis and publication of the virtual surrogates of the objects, and encourages collaboration between scientists all around the world. The pipeline is designed in a modular fashion and allows for further extensions to incorporate newer technologies. For instance, by switching scanning heads, it is possible to acquire coarser or more refined 3D geometry.

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CultLab3D: Ein mobiles 3D-Scanning Szenario für Museen und Galerien

2014

EVA 2014 Berlin. Proceedings

Electronic Imaging & the Visual Arts (EVA) <21, 2014, Berlin, Germany>

Im Projekt CultLab3D werden Kulturgüter dreidimensional und in sehr hoher Qualität erfasst. Dabei geht es um die Entwicklung einer neuartigen Scan-Technologie in Form eines mobilen Digitalisierungslabors, das aus flexibel einsetzbaren Modulen für die schnelle und ökonomische Erfassung von 3DGeometrie-, Textur- und Materialeigenschaften besteht. Dabei soll langfristig die Qualität der Daten auch wissenschaftlichen Ansprüchen genügen, die bislang Originalvorlagen erfordern. Das System soll hinsichtlich des Aufwands (u.a. Scan-Geschwindigkeit), der erzielbaren Qualität und der Kosten den Markt revolutionieren. Eine Marktreife wird für 2015 erwartet.

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Zander-Walz, Sebastian; Kuijper, Arjan [Betreuer]; Braun, Andreas [Betreuer]

Curved Large-Area Surfaces for Gestural Interaction

2014

Darmstadt, TU, Bachelor Thesis, 2014

Gestures are a natural and intuitive part of human communication. Since the appearance of smartphones and tablet computers, gestural interaction became suitable to many customers. Usually gesture interaction is implemented using two dimensional planar surfaces, although the natural movement of the human body results in elliptic or spherical paths. This thesis shows a way of equipping large-area curved surfaces with capacitive loading-mode proximity sensors and gesture recognition from theses sensors data. Therefore already existing techniques, wellknown from the use in planar system, were adapted to the use in curved prototypes. To prove the results both, the interaction with the prototype and the gesture recognition have been evaluated and the results discussed.

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Franke, Tobias

Delta Voxel Cone Tracing

2014

IEEE International Symposium on Mixed and Augmented Reality - Science & Technology 2014

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <13, 2014, Munich, Germany>

Mixed reality applications which must provide visual coherence between synthetic and real objects need relighting solutions for both: synthetic objects have to match lighting conditions of their real counterparts, while real surfaces need to account for the change in illumination introduced by the presence of an additional synthetic object. In this paper we present a novel relighting solution called Delta Voxel Cone Tracing to compute both direct shadows and first bounce mutual indirect illumination. We introduce a voxelized, pre-filtered representation of the combined real and synthetic surfaces together with the extracted illumination difference due to the augmentation. In a final gathering step this representation is conetraced and superimposed onto both types of surfaces, adding additional light from indirect bounces and synthetic shadows from antiradiance present in the volume. The algorithm computes results at interactive rates, is temporally coherent and to our knowledge provides the first real-time rasterizer solution for mutual diffuse, glossy and perfect specular indirect reflections between synthetic and real surfaces in mixed reality.

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Liang, Rong-Hao; Chan, Liwei; Tseng, Hung-Yu; Kuo, Han-Chih; Huang, Da-Yuan; Yang, De-Nian; Chen, Bing-Yu; Große-Puppendahl, Tobias; Beck, Sebastian; Wilbers, Daniel; Kuijper, Arjan; Heo, Heejeong; Park, Hyungkun; Kim, Seungki; Chung, Jeeyong; Lee, Geehyuk; Lee, Woohun; Unander-Scharin, Carl; Unander-Scharin, Aasa; Höök, Kristina; Elblaus, Ludvig

Demo Hour

2014

Interactions

Conference on Human Factors in Computing Systems (CHI) <32, 2014, Toronto,Canada>

Interactivity is a unique forum of the ACM CHI Conference that showcases hands-on demonstrations, novel interactive technologies, and artistic installations. At CHI 2014, we aimed to create a "one of a CHInd" Interactivity experience with more than 60 interactive exhibits to highlight the diverse group of computer scientists, sociologists, designers, psychologists, artists, and many more that make up the CHI community.

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Wang, Anqi; Sakas, Georgios [1. Gutachter]; Noll, Matthias [Betreuer]

Detektion von Tumorgewebe und invasiver Tumorgrenze in CD3/CD8 gefärbten Gewebeschnitten (Histopathologien)

2014

Darmstadt, TU, Master Thesis, 2014

Konventionelle Krankheitsprognose bei Krebserkrankungen basiert auf Größe des Tumors, Auftrittsort von Krebszellen und Vorliegen von Metastasen. Diese Anzeichen lassen jedoch keine Aussage über den postoperativen Krankheitsverlauf zu. Erste Studien haben ergeben, dass in solchen Fällen die Betrachtung der Immunantwort des Körpers eine zuverlässigere Vorhersage treffen kann. Die Immunantwort drückt sich in Art und Auftrittshäufigkeit von Immunzellen (sogenannte T-Zellen) in und um den Tumor aus. Zur Validierung dieser These wird in der vorliegenden Arbeit ein Verfahren entwickelt, das automatisch auf CD3/CD8-gefärbten histopathologischen Aufnahmen den Tumor und die invasive Tumorgrenze segmentiert. In Kombination mit einer anderen Arbeit, die ein Verfahren zur Zellenzählung implementiert, sollen große Datenmengen von Patienten evaluiert werden, deren Krankheitsverlauf bekannt ist. Die größte Herausforderung dieser Arbeit besteht im verwendeten Material. Üblicherweise wird Gewebe auf HE-gefärbten Aufnahmen segmentiert. CD3/CD8 sind hingegen Färbungen, welche T-Zellen klar erkennbar darstellen, aber unterschiedliche Gewebearten nur wenig differenzieren. Eine zusätzliche Schwierigkeit ist die Entwicklung des Verfahrens bei einer kleinen Menge an verfügbaren Trainings- und Testdaten. Aus der Aufgabenstellung ergeben sich für das Verfahren die Anforderungen Geschwindigkeit (Evaluation großer Datenmengen) und Genauigkeit der Segmentierung. Die Geschwindigkeitsanforderung wird erfüllt, indem effizient zu berechnende und gleichzeitig aussagekräftige Features als Eingabe für ein Clustering-Algorithmus verwendet werden. Die Verarbeitung einer Aufnahme dauert durchschnittlich 5 Minuten. Gemessen an dem Zeitaufwand eines Pathologen für die gleiche Aufgabe ist dies eine große Zeitersparnis. Die Evaluation ergab einen durchschnittlichen Accuracy-Wert von 0,94. Dieser Wert ist vergleichbar mit den Ergebnissen verwandter State of the Art Methoden, welche auf HE-gefärbten Aufnahmen arbeiten.

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Deterministic Local Layouts through High-Dimensional Layout Stitching

2014

Human-Computer Interaction: Part 1

International Conference on Human-Computer Interaction (HCII) <16, 2014, Heraklion, Crete, Greece>

In this paper we present a layout technique for dynamic views of large static graphs. It aims to minimize changes between two consecutive frames and most importantly, it is deterministic. First, a set of small layout patches is pre-computed. Then, depending on the users view focus, a subset of these patches is selected and connected to generate the final layout. In contrast to the state-of-the-art approach that operates in the 2D screen space only, we perform this process in high-dimensional space before projecting the results into the 2D plane. This gives additional degrees of freedom and consequently a smoother transition process between two consecutive frames. Whenever the user visits an area of the graph for a second time, the layout will still look the same. This enables the user to recognize areas that have already been explored and thus preserve the mental map.

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Die mobile Digitalisierstraße CultLab3D

2014

KulturBetrieb

Während die digitale Erfassung von kulturellen Artefakten in 2D heute effizient und kostengünstig möglich und bereits weit verbreitet ist, ist die 3D-Digitalisierung noch immer zeit- und kostenintensiv. Gleichzeitig steigt der Wunsch, Museums- und Archivbestände auch in 3D zu erfassen und verschiedenen Anspruchsgruppen zugänglich zu machen. Die vom Fraunhofer IGD entwickelte digitale Scanstraße CultLab3D soll die Digitalisierung dreidimensionaler Objekte revolutionieren.

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Fuhrmann, Constanze [Betreuer]

Die Temperierung. Beiträge zum aktuellen Forschungsstand

2014

Schriftenreihe des Bayerischen Landesamtes für Denkmalpflege

Im Rahmen des Forschungsprojekts "Sammlungen erhalten: Die Temperierung als Mittel der Präventiven Konservierung - Eine Bewertung" veranstaltete die Landesstelle für die nichtstaaatlichen Museen in Bayern im November die Tagung "Die Temperierung - Beiträge zum aktuellen Forschungsstand" im Kloster Benediktbeuren und lud Fachleute und Interessenten ein, sich über den aktuellen Entwicklungsstand der Temperierung zu informieren. Die Beiträge sind in diesem Band zusammengefasst und zeigen die - nicht immer kongruenten - Meinungen zur Temperierung auf.

  • 978-3-86222-144-8
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Schwertel, Uta; Diener, Holger; Heinitz, Antje; Schäfer, Markus; Schlemminger, Andreas

Digitale Bildungsdienste für Elektromobilität - Beispiele aus dem Projekt MEMO

2014

IM+io

Digitale Medien, der Einsatz von Web 2.0-Technologien und mobile Anwendungen erhalten eine immer größere Bedeutung in informellen, aber auch formalen beruflichen Bildungsprozessen. Eine spannende Frage ist: Wie können digitale Bildungsdienste speziell in Berufen des Handwerks den Praxisbezug und die Nutzung an verschiedenen Lern- und Arbeitsorten unterstützen? Das Projekt MEMO entwickelte am Beispiel Elektromobilität eine Sammlung webbasierter und mobiler Lerndienste, die Wissentransfer, Kollaboration und Qualifizierung im Kfz-Handwerk und vergleichbaren Domänen unterstützen.

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Wichmann, Julian L.; Booz, Christian; Wesarg, Stefan; Kafchitsas, Konstantinos; Bauer, Ralf W.; Kerl, J. Matthias; Lehnert, Thomas; Vogl, Thomas J.; Khan, M. Fawad

Dual-Energy CT-based Phantomless in Vivo Three-dimensional Bone Mineral Density Assessment of the Lumbar Spine

2014

Radiology

Purpose: To evaluate the feasibility of phantomless in vivo dual-energy computed tomography (CT)-based three-dimensional (3D) bone mineral density (BMD) assessment in comparison with dual x-ray absorptiometry (DXA). Materials and Methods: This retrospective study was approved by the institutional review board, and the requirement to obtain informed consent was waived. Data from clinically indicated dual-energy CT and DXA examinations within 2 months, comprising the lumbar spine of 40 patients, were included. By using automated dedicated postprocessing dual-energy CT software, the trabecular bone of lumbar vertebrae L1-L4 were analyzed and segmented. A mixed-effects model was used to assess the correlations between BMD values derived from dual-energy CT and DXA. Results: One hundred sixty lumbar vertebrae were analyzed in 40 patients (mean age, 57.1 years; range, 24-85 years), 21 male (mean age, 54.3 years; range, 24-85 years) and 19 female (mean age, 58.5 years; range, 31-80 years). Mean BMD of L1-L4 determined with DXA was 0.995 g/ cm², and 18 patients (45%) showed an osteoporotic BMD (T score less than 22.5) of at least two vertebrae. Mean dual-energy CT-based BMD of L1-L4 was 0.254 g/cm³. Bland-Altman analysis with mixed effects demonstrated a lack of correlation between dual-energy CT-based and DXA-based BMD values, with a mean difference of 0.7441 and 95% limits of agreement of 0.7441 +/- 0.4080. Conclusion: Dedicated postprocessing of dual-energy CT data allows for phantomless in vivo BMD assessment of the trabecular bone of lumbar vertebrae and enables freely rotatable color-coded 3D visualization of intravertebral BMD distribution.

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Gennies, Maria; Urban, Bodo [Betreuer]; Gutzeit, Enrico [Betreuer]; Zhou, Zhiliang [Betreuer]

Echtzeit-Gesichtsdetektion und -verschleierung in Videos unter praktischen Bedingungen

2014

Magdeburg, Univ., Diplomarbeit, 2014

Die Detektion und Verschleierung von Gesichtern in Videoströmen verschiedener Kameras aus Innen- und Außengeländebereichen stellt eine besondere Herausforderung dar. In der vorliegenden Arbeit werden die theoretischen Grundlagen dieser Fragestellung näher betrachtet, ein umfassendes Konzept zur automatischen Gesichtsdetektion und -verschleierung unter den gegebenen praktischen Bedingungen entwickelt sowie die Umsetzung und Resultate der grundlegenden Systemarchitektur erläutert. Das vorgestellte prototypische System besteht aus einer Kombination von Bildvorverarbeitungsmethoden, der fensterbasierten Merkmalsextraktion mit Haar-like Features, der Lernkomponente AdaBoost, einem farbbasierten Tracking mit dem CAMShift-Algorithmus sowie einer Verschleierung. Weiterhin werden Alternativmethoden, Erweiterungen und Optimierungsmöglichkeiten zur Steigerung der Robustheit und Echtzeitfähigkeit des Systems vorgestellt.

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Liu, Yisi; Sourina, Olga

EEG-based Subject-Dependent Emotion Recognition Algorithm Using Fractal Dimension

2014

Proceedings 2014 IEEE International Conference on Systems, Man, and Cybernetics

IEEE International Conference on Systems, Man and Cybernetics (SMC) <2014, San Diego, CA, USA>

In this paper, a real-time Electroencephalogram (EEG)-based emotion recognition algorithm using Higuchi Fractal Dimension (FD) Spectrum is proposed. As EEG is a nonlinear and multi-fractal signal, its FD spectrum can give a better understanding of the nonlinear property of EEG. Three values are selected from the whole spectrum and are combined with the other features such as statistical and Higher Order Crossings ones. The Support Vector Machine is used as the classifier. The proposed algorithm is validated on both benchmark database DEAP with video stimuli and our own dataset which used visual stimuli to evoke emotions. Up to 8 emotions can be recognized with only 4 channels. The experiment analysis results show that using FD spectrum features it is possible to improve classification accuracy.

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Thürck, Daniel; Widmer, Sven; Kuijper, Arjan; Goesele, Michael

Efficient Heuristic Adaptive Quadrature on GPUs: Design and Evaluation

2014

Parallel Processing and Applied Mathematics

International Conference on Parallel Processing and Applied Mathematics (PPAM) <10, 2013, Warsaw, Poland>

Numerical integration is a common sub-problem in many applications. It can be solved easily in CPU-based applications using adaptive quadrature such as the adaptive Simpson's rule. These algorithms rely, however, on error estimation yielding a significant computational overhead. In addition, they require recursive function evaluations, which are not well suited for parallel computation on graphics processing units (GPUs) due to warp divergence issues. In this paper, we introduce heuristic forward quadrature as an alternative that is not only more efficient than traditional methods, but also better suited for accelerated massively-parallel calculation on GPUs. Additionally, we will give an error estimate for our method and demonstrate performance results for 1D and 2D integral applications which show that the algorithm leverages quadrature for the efficient implementation on GPUs.

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Schiffer, Thomas; Fellner, Dieter W.

Efficient Multi-kernel Ray Tracing for GPUs

2014

GRAPP 2014

International Conference on Computer Graphics Theory and Applications (GRAPP) <9, 2014, Lisbon, Portugal>

Images with high visual quality are often generated by a ray tracing algorithm. Despite its conceptual simplicity, designing an efficient mapping of ray tracing computations to massively parallel hardware architectures is a challenging task. In this paper we investigate the performance of state-of-the-art ray traversal algorithms for bounding volume hierarchies on GPUs and discuss their potentials and limitations. Based on this analysis, a novel ray traversal scheme called batch tracing is proposed. It decomposes the task into multiple kernels, each of which is designed for efficient parallel execution. Our algorithm achieves comparable performance to currently prevailing approaches and represents a promising avenue for future research.

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Efficient Self-Shadowing Using Image-Based Lighting on Glossy Surfaces

2014

VMV 2014

Workshop on Vision, Modeling, and Visualization (VMV) <19, 2014, Darmstadt, Germany>

In this paper we present a novel natural illumination approach for real-time rasterization-based rendering with environment map-based high dynamic range lighting. Our approach allows to use all kinds of glossiness values for surfaces, ranging continuously from completely diffuse up to mirror-like glossiness. This is achieved by combining cosine-based diffuse, glossy and mirror reflection models in one single lighting model. We approximate this model by filter functions, which are applied to the environment map. This results in a fast, image-based lookup for the different glossiness values which gives our technique the high performance that is necessary for real-time rendering. In contrast to existing real-time rasterization-based natural illumination techniques, our method has the capability of handling high gloss surfaces with directional self-occlusion. While previous works exchange the environment map by virtual point light sources in the whole lighting and shadow computation, we keep the full image information of the environment map in the lighting process and only use virtual point light sources for the shadow computation. Our technique was developed for the usage in real-time virtual prototyping systems for garments since here typically a small scene is lit by a large environment which fulfills the requirements for imagebased lighting. In this application area high performance rendering techniques for dynamic scenes are essential since a physical simulation is usually running in parallel on the same machine. However, also other applications can benefit from our approach.

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Schönfelder, Tom; Urban, Bodo [Betreuer]; Aehnelt, Mario [Betreuer]

Einsatz kognitiver Architekturen für die Anleitung von Montagearbeiten : Vergleichende Darstellung ausgewählter Konzepte

2014

Rostock, Univ., Studienarbeit, 2014

Die vorliegende Arbeit untersucht verschiedene Modellierungen von kognitiven Architekturen hinsichtlich ihrer Eignung als Assistenzsysteme in technischen Anwendungen. Hierbei sind eine Reihe von Kriterien zu berücksichtigen, welche je nach Anwendungsfall unterschiedlich zu bewerten sind. Dem Leser soll ein Überblick über den aktuellen Stand der Technik vermittelt werden, anhand dessen die Auswahl einer geeigneten Modellierung für einen gegebenen Anwendungsfall erleichtert werden kann. Bei den betrachteten Architekturen handelt es sich um Soar, ACT-R, ICARUS, EPIC und 4CAPS.

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Enhanced Shadow Detection for 3D Ultrasound

2014

Bildverarbeitung für die Medizin 2014

Workshop Bildverarbeitung für die Medizin (BVM) <2014, Aachen, Germany>

Ultrasound imaging offers a fast, convenient and save instrument to conduct patient examinations for various medical scenarios. However, depending on the target region, occluding bone segments and other materials cause large and undesirable shadowing artifacts. Thus, the experience of the ultrasound operator is crucial for obtaining an ultrasound without artifacts for patient diagnosis. Even more so, when applying automated image processing algorithms. We therefore like to introduce our automatic 3D ultrasound shadow detection method that employs scan line energy and local image entropy information. Applying the method can help to prevent low quality image acquisitions with large shadowing artifacts by indicating shadow occurrences.

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Konstantinos, Votis; Karras, Yiannis; Kohlhammer, Jörn; Steiger, Martin; Tzovaras, Dimitrios; Gounopoulos, Elias

Enhanced Visual Analytics Services for the Optimal Planning of Renewable Energy Resources Installations

2014

Artificial Intelligence Applications and Innovations

International Conference on Artificial Intelligence Applications and Innovations (AIAI) <10, 2014, Rhodes, Greece>

This paper presents an integrated and novel service environment for real-time interactions between users, as well as enhanced visualization and decision support services over extremely large volumes of heterogeneous Renewable data sources. The integrated visual analytics methods, allow energy analysts to incorporate their expert knowledge into the analysis, so as to dynamically investigate the observed events and locations, and accurately identify the preferable results. The goal of visual analytics research is to turn the information overload into an opportunity by enabling decision-makers to examine this massive amount of information to make effective decisions.

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Mouton, Christophe; Parfouru, Samuel; Jeulin, Clotilde; Dutertre, Cecile; Goblet, Jean-Louis; Paviot, Thomas; Lamouri, Samir; Limper, Max; Stein, Christian; Behr, Johannes; Jung, Yvonne

Enhancing the Plant Layout Design Process using X3DOM and a Scalable Web3D Service Architecture

2014

Proceedings Web3D 2014

International Conference on 3D Web Technology (WEB3D) <19, 2014, Vancouver, BC, Canada>

This paper presents an innovative model-driven architecture enabling 3D web-based design processes in the field of large complex building (LBC) projects, such as power plant construction. This work was motivated by proposing new ways of achieving 3D CAD tasks not only for highly complex and temporary organization in the design stages but also for the whole lifecycle of such installations, which may last several decades. in this particular scenario, it is very important to share the right information with the right stakeholder at the right time, to maintain a high level of knowledge sharing. Taking into account these challenges, we propose a first implementation of interactive 3D CAD editing tools, based on the X3DOM technology and driven by a knowledge layer which utilizes a complete reference data and rules management system. To store the CAD models, a Macro-Parametric Approach has been investigated and a 3D server has been added to the traditional PDM (Product or Plant Data Management) to execute remotely complex CAD operations. This is a very promising start to deploy lightweight and smart web3D CAD editing services for the AEC (Architecture Engineering Construction) and power industries.

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Knaub, Anton; Drechsler, Klaus [Betreuer]

Entwicklung eines Appearance Models zur modellbasierten Lebersegmentierung in MRT-Daten

2014

Darmstadt, Hochschule, Bachelor Thesis, 2014

Der Standard der Diagnostizierung von Lebertumoren in der Radiologie ist bis heute die Computertomographie (CT). Auf Basis dieser Daten wurden zahlreiche Segmentierungsverfahren entwickelt und erfolgreich für die automatisierte Diagnose und Planung von Interventionen eingesetzt. Die Gefahr bei CT besteht darin, dass der Patient einer erhöhten Strahlungsdosis ausgesetzt wird. Dies ist einer der Gründe, weswegen die Magnetresonanztomographie (MRT) verstärkt von Radiologen zur Diagnose eingesetzt wird. Es gibt viele Ansätze zur Segmentierung von Organen wie der Leber. Besonders gute Ergebnisse wurden mit modellbasierten Ansätzen für die automatische Segmentierung der Leber in CT-Daten entwickelt. Auf den Wunsch der Radiologen soll auch eine Lebersegmentierung auf MRT-Daten ermöglicht werden. Aus diesem Grund wird in dieser Arbeit ein bestehendes modellbasierendes Verfahren, das Probabilistic Active Shape Model von Matthias Kirschner, aufgegriffen und um ein Appearance Model für MRT-Daten erweitert und somit eine Lebersegmentierung auf MRT-Daten ermöglicht. Dazu wird eine geeignete Vorverarbeitungspipeline für MRT-Lebern gewählt. Des Weiteren werden verschiedene Trainingsmethoden des Appearance Models untersucht und die geeignetste selektiert und evaluiert. Die Ergebnisse der Evaluation der Segmentierung auf acht kontrastinjizierten Lebern liefern einen durchschnittlichen Volumenüberlappungsfehler von 13,37 % bei einer durchschnittlichen Oberflächendistanz von 2,39 mm.

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Bendix, Anne; Urban, Bodo [Betreuer]; Mesing, Benjamin [Betreuer]

Entwicklung eines Authoring-Ansatzes für die Anreicherung von 3D-Szenen mit Verhalten für das 3D-Web

2014

Rostock, Univ., Bachelor Thesis, 2014

Dynamische 3D-Szenen finden heutzutage in vielen Bereichen Anwendung, wie beispielsweise in der Industrie oder zu Lern- und Ausbildungszwecken. Eine statische 3D-Szene lässt sich leicht mit Hilfe von CAD-Programmen erstellen, doch das Einbringen der dynamischen Aspekte erfolgt meist von Hand und stellt eine große Hürde dar. In dieser Arbeit wird ein Konzept vorgestellt, mit welchem Verhalten in eine 3D-Szene in einem bestimmten 3DWeb-Format eingebracht werden kann. Das Konzept wird auf Basis eines bereits existierenden Datenaufbereitungsframeworks beispielhaft für X3DOM umgesetzt. Dabei wird das Framework im Hinblick auf die Anreicherung optimiert. Durch die Einführung verschiedener Abstraktionsebenen soll eine Entkoppelung vom zugrunde liegenden 3DWeb-Format erfolgen. Dadurch soll eine Unterstützung weiterer 3DWeb- Formate künftig erleichtert werden.

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Eckeren, Katharina van; Kuijper, Arjan [Betreuer]; Goesele, Michael [2. Gutachter]; Tausch, Reimar [Betreuer]

Entwicklung und Evaluation eines 3D Object Retrieval Systems für digitalisierte Kulturobjekte

2014

Darmstadt, TU, Master Thesis, 2014

Diese Arbeit befasst sich mit dem Aufbau, der Entwicklung und der Auswertung eines 3D Object Retrieval-Systems zur Ähnlichkeitssuche von digitalisierten Kulturobjekten. Nach der Einordnung und Vorstellung des verwendeten Beschreibungsverfahrens für 3D Objekte, namens 3D Histogram of Oriented Gradients (Abk. 3D-HOG) [1][2], in den Kontext des aktuellen State-of-the-Art erfolgt eine Erläuterung jeder verwendeten Komponente des Systems. Neben der ausführlichen Erklärung der Funktionsweise von 3D-HOG und seinen Stärken und Schwächen wurde für seine Auswertung eine Datengrundlage, bestehend aus 3D Kulturobjekten mit einer sehr hohen Polygonnetzauflösung, erstellt. Die Auswertung betrachtet verschiedene Parameterangaben und benutzt zur anfänglichen Bewertung das Maß der R-Precision [3]. Durch die Anpassung der Blocknormalisierung, der Zellenanzahl und der Gradientenfeldgröße, die drei wichtigsten Parameter des 3D-HOG Verfahrens, konnte die R-Precision von 0.799 auf 0.888 verbessert werden. Außerdem zeigte sich, dass die Polygonnetzauflösung der Objekte von sekundärer Bedeutung ist, da sie kaum einen Einfluss auf die Ergebnisse der gewählten Beschreibungsverfahren hat.

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Krause, Tom; Lukas, Uwe von [Betreuer]; Vahl, Matthias [Betreuer]; Gutzeit, Enrico [Betreuer]

Ereignisdetektion in Bildfolgen

2014

Rostock, Univ., Diplomarbeit, 2014

Diese Diplomarbeit behandelt die Ereigniserkennung in Bildfolgen. Dabei soll der Anwendungsfall "Ereignisdetektion in an Bord von Fischereifahrzeugen aufgenommenen Überwachungsvideos" adressiert werden. Nach einem Überblick über die Grundlagen werden Konzeption und Umsetzung eines Systems erläutert, welches die Ereigniserkennung erleichtern soll. Bedingt durch den Anwendungsfall wird dabei vermehrt auf die Erkennung von Meerwasser eingegangen, welches einen wichtigen Kontext für viele Ereignisse da stellt.

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Koa, Ming Di; Johan, Henry

ESLPV: Enhanced Subsurface Light Propagation Volumes

2014

The Visual Computer

Computer Graphics International (CGI) <31, 2014, Sydney, Australia>

In this paper, we present an Enhanced Subsurface Light Propagation Volumes (ESLPV) method for real-time rendering of translucent materials. Our method is an extension of the Subsurface Light Propagation Volumes (SSLPV) technique. We improve the SSLPV by incorporating a single scattering framework that uses the same Spherical Harmonics (SH) storage structure as the SSLPV. The new single scattering technique deposits radiance as SH coefficients during a ray marching procedure. The final result is rendered using a ray tracer with importance sampling along the camera ray. This framework also enables the ESLPV to render refractive objects. In addition, we also propose a distance transform optimization that can remove the unnecessary computations during the propagation cycle of LPV [17] based methods. A hierarchical propagation process is also proposed to render highly translucent materials. Similar to the SSLPV, our ESLPV method contains no precomputations, and has low storage requirements that is independent of the mesh size.

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Wuhrer, Stefanie; Pishchulin, Leonid; Brunton, Alan; Shu, Chang; Lang, Jochen

Estimation of Human Body Shape and Posture Under Clothing

2014

Computer Vision and Image Understanding

Estimating the body shape and posture of a dressed human subject in motion represented as a sequence of (possibly incomplete) 3D meshes is important for virtual change rooms and security. To solve this problem, statistical shape spaces encoding human body shape and posture variations are commonly used to constrain the search space for the shape estimate. In this work, we propose a novel method that uses a posture-invariant shape space to model body shape variation combined with a skeleton-based deformation to model posture variation. Our method can estimate the body shape and posture of both static scans and motion sequences of human body scans with clothing that fits relatively closely to the body. In case of motion sequences, our method takes advantage of motion cues to solve for a single body shape estimate along with a sequence of posture estimates. We apply our approach to both static scans and motion sequences and demonstrate that using our method, higher fitting accuracy is achieved than when using a variant of the popular SCAPE model [2, 18] as statistical model.

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Carr, Hamish [Ed.]; Rheingans, Penny [Ed.]; Schumann, Heidrun [Betreuer]

EuroVis 2014. Eurographics Conference on Visualization 2014

2014

Computer Graphics Forum

Eurographics Conference on Visualization (EuroVis) <16, 2014, Swansea, Wales, UK>

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Bienert, Andreas [Hrsg.]; Santos, Pedro [Betreuer]; Hemsley, James [Hrsg.]

EVA 2014 Berlin. Proceedings

2014

Electronic Imaging & the Visual Arts (EVA) <21, 2014, Berlin, Germany>

In den Workshops zum 3D-Scanning von historischem Kulturgut werden die technischen und semantischen Themenbereiche von der Datenakquise bis hin zur Visualisierung aufgefächert und zur Diskussion gestellt. Erstmals wird die Möglichkeit geboten, CultLab3D, ein mobiles 3D-Scanning Szenario für Museen und Galerien, im konkreten Arbeitszusammenhang zu erproben. Unter dem Titel "Attention! Wahrnehmung und Vermittlung in der digitalen Gesellschaft" widmet sich ein dritter Workshop den Auswirkungen, die sich aus 3D-Modellen, immersiven Bildwelten und Augmented Reality Anwendungen für unsere Wahrnehmung und das kollektive Bewusstsein einstellen. Sie verändern den Horizont unserer Erfahrungen und die Art und Weise, wie wir Geschichte/n weitergeben. An den beiden Konferenztagen wird das Thema der digitalen Modellbildung dann für die unterschiedlichen Einsatzbereiche fortgeführt. Das Spektrum reicht von der 3D-Visualisierung über die Organisation von Wissen in Portalen, in Datenverbünden und in Netzwerken bis hin zu technologisch innovativen Präsentationsformaten und neuen Möglichkeiten der Besucherbindung.

  • 978-3-88609-755-5
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Hänler, Anna; Gutzeit, Enrico; Mertins, Alfred

Evaluation of Methods for Automatic Fish Segmentation

2014

Student Conference on Medical Engineering Science 2014. Proceedings

Student Conference on Medical Engineering Science <3, 2014, Lübeck, Germany>

Bycatch in the fishery endangers whole ecological systems in worldwide waters. By identifying and counting the marine animals of the bycatch, fishing techniques could be improved which would reduce the bycatch in turn. To ensure good identification, an excellent segmentation of the fish in photos taken from the bycatch is important. Six different segmentation methods are tested, which are Otsu's method, the Watershed algorithm, Region Growing, K-Means, K-Means distance probability and Gaussian Mixture Models (GMM) distance probability, with the two latter ones calculating probabilities for each pixel of an image for belonging to the fore- or the background. The methods are compared with the F-Measurement, the harmonic mean of precision and recall, to evaluate their accuracy. The result of this work will show that the best method for the seven tested fish species is the automatic K-Means algorithm, which is easy to use in practice.

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Steiger, Martin; Hutter, Marco; Schader, Philipp; Kohlhammer, Jörn; Kuijper, Arjan

Exploring Simulation in Sensor Network Models

2014

VMV 2014

Workshop on Vision, Modeling, and Visualization (VMV) <19, 2014, Darmstadt, Germany>

Simulation is an important measure to estimate different properties of a planned network such as throughput and cost. However, many parameters need to be adjusted to approximate real-world conditions properly. In this paper we present a visualization system that visually supports and guides the analysis of (physical) network simulation problems. Automatic optimizers run as a black box giving an (locally) optimal result in terms of the underlying simulation model and parameter configuration. This is often not ideal for practical usage. Our system assists the user in the process of comparing different simulations to quickly achieve the optimal configuration in terms of user preference. It highlights differences between simulation runs and indicates which parameter modification leads to the best improvement. We expect that this results in large time savings for the domain expert while configuring the simulation system.

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Krispel, Ulrich; Ullrich, Torsten; Fellner, Dieter W.

Fast and Exact Plane-based Representation for Polygonal Meshes

2014

Proceedings of the International Conferences on Interfaces and Human Computer Interaction 2014, Game and Entertainment Technologies 2014 and Computer Graphics, Visualization, Computer Vision and Image Processing 2014

IADIS International Conference Computer Graphics, Visualization, Computer Vision and Image Processing (CGVCVIP) <8, 2014, Lisbon, Portugal>

Boolean operations on meshes tend to be non-robust, due to the rounding of newly constructed vertex coordinates. Plane-based mesh representations are known to circumvent the problem for meshes with planar faces: geometric information is stored by face equations, and vertices (as well as newly constructed vertices) are expressed as plane triplets. We first review the properties of plane-based mesh representations and discuss a variant that is optimized for fast evaluation using fixed integer precision and give some practical insights on implementing search structures for indexing of planes and vertices in this representation.

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Wesarg, Stefan; Wichmann, Julian L.; Booz, Christian; Erdt, Marius; Kafchitsas, Konstantinos; Khan, M. Fawad

First Clinical Experience with BMD Assessment in Vertebrae Using Dual-Energy CT

2014

Clinical Image-Based Procedures. Translational Research in Medical Imaging

International Workshop on Clinical Image-based Procedures (CLIP) <2, 2013, Nagoya, Japan>

Dual-energy CT (DECT) can be performed with state-of-the- art dual-source CT (DSCT) scanners and allows for assessing bone mineral density (BMD). In this work, we present first clinical experience with in vivo BMD assessment of vertebrae based on DECT data which has been acquired with a state-of-the-art DSCT scanner in the clinical routine. In contrast to previous work where we did in vitro tests of our method, we apply it her for the first time to in vivo data and prove the feasibility of our technique in a clinical setting. For 25 patients, DXA as well as DECT data have been acquired and BMD of vertebrae was assessed. Advantages of DECT are its 3D capabilities allowing to compute the spatial BMD distribution and to focus the examination on the trabecular bone. Correlations between both imaging techniques regarding the averaged BMD values per vertebra are only moderate.

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Fuhrmann, Simon; Goesele, Michael

Floating Scale Surface Reconstruction

2014

ACM Transactions on Graphics

International Conference on Computer Graphics and Interactive Techniques (SIGGRAPH) <41, 2014, Vancouver, BC, Canada>

Any sampled point acquired from a real-world geometric object or scene represents a finite surface area and not just a single surface point. Samples therefore have an inherent scale, very valuable information that has been crucial for high quality reconstructions. We introduce a new method for surface reconstruction from oriented, scale-enabled sample points which operates on large, redundant and potentially noisy point sets. The approach draws upon a simple yet efficient mathematical formulation to construct an implicit function as the sum of compactly supported basis functions. The implicit function has spatially continuous "floating" scale and can be readily evaluated without any preprocessing. The final surface is extracted as the zero-level set of the implicit function. One of the key properties of the approach is that it is virtually parameter-free even for complex, mixed-scale datasets. In addition, our method is easy to implement, scalable and does not require any global operations. We evaluate our method on a wide range of datasets for which it compares favorably to popular classic and current methods.

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Follow-Me: Smartwatch Assistance on the Shop Floor

2014

HCI in Business

International Conference on Human-Computer Interaction in Business (HCIB) <1, 2014, Heraklion, Crete, Greece>

The growing complexity of manufacturing calls for new approaches to support the human workforce with situation-aware information and tools which in consequence ease the process of understanding and applying work related knowledge. With this paper we introduce a theoretical model for a systematic information transfer between assistance system and worker. It defines assistance objectives and reviews the role of artifacts during the assistance process focusing on the cognitive aspects of work. Our approach was implemented using smartwatches for application in industrial assembly environments extending the Plant@Hand manufacturing performance support system.

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Ladenhauf, Daniel; Berndt, René; Eggeling, Eva; Ullrich, Torsten; Battisti, Kurt; Gratzl-Michlmair, Markus

From Building Information Models to Simplified Geometries for Energy Performance Simulation

2014

Proceedings of International Academic Conference on Places and Technologies

International Academic Conference on Places and Technologies <1, 2014, Belgrade, Serbia>

A major future challenge in the building industry is to reduce primary energy use of buildings. EU law now requires energy performance certificates to be issued for all buildings. Hence, energy performance simulation becomes an increasingly important topic. Accurate, yet efficient simulation depends on simple building models. Most of the required data can be found in Building Information Models (BIM), following the buildingSMART alliance's Industry Foundation Classes (IFC) schema. IFC has become an ISO standard and enjoys increasing support by CAD software. However, typical IFC models contain a lot of irrelevant data, in particular geometric representations, which are too detailed for energy performance simulation. Therefore, an algorithm is proposed for extracting input models for simulations directly from IFC models in a semi-automatic process, to overcome the current situation where simple models are manually built from scratch. The key aspect of the algorithm is geometry simplification subject to semantic and functional groups; more specifically, the 3D representations of walls, slabs, windows, doors, etc. are reduced to a collection of surfaces describing the building's thermal shell on one hand, and the material layers associated with it on the other hand. Test models from simple fictitious houses to complex models of real-world buildings have been provided to guide the development of the algorithm in an incremental manner. This paper presents the resulting algorithm and the current status of prototype software implementing it.

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From Raw Data to Rich Visualization: Combining Visual Search with Data Analysis

2014

Towards the Internet of Services: The THESEUS Research Program

Visual analytics is an interdisciplinary field of research at the boundary between data mining, statistics and visualization. Patterns and relations in the data complement a semantic representation of knowledge on a lower level of abstraction. One important goal of visual analytics is to find relations hidden in vast amounts of data, which can be turned into useful knowledge. Analysis needs to be "visual", because human's visual cognitive abilities are important for the identification and refinement of the analytical process. Further the results of the analysis have to be presented in a way to match the user's perspective on the proposed task. However, typical users are not experts in statistics or data mining. The challenge of visual analytics is to keep domain experts in charge of the analytical process while reducing the workload due to the complexity of the techniques. While search and analysis usually arc mentioned in different contexts, they are highly interdependent processes. In fact, every exploratory analysis is a search for new knowledge. In turn, this knowledge can be used to refine future searches by introducing new concepts or relations to draw from. This article will show how automated and visual methods can be combined to connect knowledge artifacts on multiple levels of abstraction.

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Fundamental Aspects for E-Government

2014

Handbook of Research on Advanced ICT Integration for Governance and Policy Modeling

The upcoming initiatives using ICT in the government process should strengthen the benefit of E-Government in most countries. Since E-Government among other e-related terms is a widely (interpreted) term, it is sometimes challenging to understand the objective and goals of an initiative. Therefore in this paper we introduce and explain the most E-Government related terms. Even more, we outline some interesting initiatives and implementations to explain the benefits of using ICT in the government domain. So next to the term description, concrete activities will be aligned to the terms to explain the practical use in a better way. We conclude with several challenges that arise when thinking of the implementation of E-Government services. Overall this chapter should give a good overall view about E-Government and the relating issues.

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Ginters, Egils; Aizstrauts, Artis; Baltruks, Mikelis; Nazemi, Kawa; Burkhardt, Dirk; Sonntagbauer, Peter; Sonntagbauer, Susanne; Gutierrez, Jorge Martin

Fupol Simulators and Advanced Visualization Framework Integration

2014

26th European Modeling and Simulation Symposium

European Modeling and Simulation Symposium (EMSS) <26, 2014, Bordeaux, France>

FP7 FUPOL project No.287119 (see www.fupol.eu) aims at a new approach to traditional politics modeling. The FUPOL will be able to automatically collect, analyze and interpret opinions expressed on a large scale from the Internet and social networks. This will enable governments to gain a better understanding of the needs of citizens. Likewise the software will have the capabilities to simulate the effects of policies and laws and to assist governments in the whole policy design process. Basic visualization of the simulation results are supported by the simulators however visualization facilities are limited, therefore for detailed visual analysis of simulation data SemasVis environment is used.

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Fusing Web Technologies & Augmented Reality

2014

IEEE International Symposium on Mixed and Augmented Reality - Science & Technology 2014

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <13, 2014, Munich, Germany>

Within the German research project ARVIDA a large consortium of industrial Virtual and Augmented Reality users, of technology providing companies and research institutes cooperate on the establishment of highly flexible web-based reference architecture for Augmented Reality applications. The use of web technologies is motivated by modern web standards as WebGL or WebRTC supporting e.g. real time rendering of 3D-content of video streaming within Web-Browsers. Thereby, the use of Web technologies not only offers the possibility to develop applications platform and OS independent but it also facilitates the integration of Augmented Reality into industrial workflows or PDM environments. The developed reference architecture offers RESTful tracking, rendering and interaction services that foster the combination and exchange of different algorithms with the aim to fit the technology to the specific requirements of an AR-applications in an optimal way.

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Preiss, Jens; Fairchild, Mark D.; Ferwerda, James A.; Urban, Philipp

Gamut Mapping in a High-Dynamic-Range Color Space

2014

Color Imaging XIX: Displaying, Processing, Hardcopy, and Applications

Color Imaging: Processing, Hardcopy, and Applications <19, 2014, San Francisco, CA, USA>

In this paper, we present a novel approach of tone mapping as gamut mapping in a high-dynamic-range (HDR) color space. High- and low-dynamic-range (LDR) images as well as device gamut boundaries can simultaneously be represented within such a color space. This enables a unified transformation of the HDR image into the gamut of an output device (in this paper called HDR gamut mapping). An additional aim of this paper is to investigate the suitability of a specific HDR color space to serve as a working color space for the proposed HDR gamut mapping. For the HDR gamut mapping, we use a recent approach that iteratively minimizes an image-difference metric subject to in-gamut images. A psychophysical experiment on an HDR display shows that the standard reproduction workflow of two subsequent transformations - tone mapping and then gamut mapping - may be improved by HDR gamut mapping.

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Klein, Reinhard [Betreuer]; Santos, Pedro [Betreuer]; Fellner, Dieter W. [Betreuer]; Scopigno, Roberto [Event Co-Chair]

GCH 2014

2014

Eurographics Symposium on Graphics and Cultural Heritage (GCH) <12, 2014, Darmstadt, Germany>

Focus of this year's forum is to present and showcase new developments within the overall process chain, from data acquisition, 3D documentation, analysis and synthesis, semantical modelling, data management, to the point of virtual museums or new forms of interactive presentations and 3D printing solutions. GCH 2014 therefore provides scientists, engineers and CH managers a possibility to discuss new ICT technologies applied to data modelling, reconstruction and processing, digital libraries, virtual museums, interactive environments and applications for CH, ontologies and semantic processing, management and archiving, standards and documentation, as well as its transfer into practice.

  • 978-3-905674-63-7
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Klein, Reinhard [Betreuer]; Santos, Pedro [Betreuer]; Fellner, Dieter W. [Betreuer]; Scopigno, Roberto [Event Co-Chair]

GCH 2014. Short Papers - Posters

2014

Eurographics Symposium on Graphics and Cultural Heritage (GCH) <12, 2014, Darmstadt, Germany>

Focus of this year's forum is to present and showcase new developments within the overall process chain, from data acquisition, 3D documentation, analysis and synthesis, semantical modelling, data management, to the point of virtual museums or new forms of interactive presentations and 3D printing solutions. GCH 2014 therefore provides scientists, engineers and CH managers a possibility to discuss new ICT technologies applied to data modelling, reconstruction and processing, digital libraries, virtual museums, interactive environments and applications for CH, ontologies and semantic processing, management and archiving, standards and documentation, as well as its transfer into practice. Short papers present preliminary results and work-in-progress or focusing on on-going projects, the description of project organization, use of technology, and lesson learned.

  • 978-3-905674-75-0
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Dreißig, Martin; Deistung, Eik [Betreuer]

Generative Schiffsmodellierung

2014

Wismar, Hochschule, Master Thesis, 2014

Die dreidimensionale Modellierung ist ein sehr verbreitetes Werkzeug um mediale Inhalte zu schaffen. Es wird in vielen verschiedenen Bereichen, wie z.B. der Spiele und Nachrichtenbranche genutzt, um 3D-Objekte und -Szenen zu generieren. Ziel dieser 3D-Graffiken ist es, dem Betrachter Informationen anschaulicher übermitteln zu können - durch beispielsweise Inszenierungen von Zukunftsvisionen, dreidimensionaler Diagrammen oder Trainingssimulationen. Ziel dieser Thesis soll es sein, ein möglichst realistisches Schiffsmodell mit einer nicht herkömmlichen Methodik zu erstellen: der generativen Modellierung. Der größte Unterschied zu konventionellen Modellierungsmethoden besteht darin, dass nicht das fertige Modell, sondern der Prozess zum Modell im Fokus steht. Die genutzte Programmiersprache GML ermöglicht es daher in die Prozesse einzugreifen und theoretisch unendlich viele Variationen der Objekte mit geringem Aufwand zu erstellen. Anhand der Vorlage eines realen Schiffes wurde diese Aufgabe umgesetzt und auf den Einsatz im übergeordneten Projekt MarOpTra-3D geprüft.

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Ladenhauf, Daniel; Berndt, René; Krispel, Ulrich; Eggeling, Eva; Ullrich, Torsten; Battisti, Kurt; Gratzl-Michlmair, Markus

Geometry Simplification According to Semantic Constraints

2014

Computer Science - Research and Development

The building industry and facility management is in a state of upheaval: The complexity of the realworld is now represented in its digital counterpart. The established object-based file format "Industrial Foundation Classes (IFC)" developed by the International Alliance for Interoperability facilitates interoperability in the context of Building Information Modeling. Unfortunately, there is no feasible workflow for filtering energy-related information, e.g. a streamlined version of the building geometry. Simplification methods often fail on CAD data that is ignorant of domain specific semantic information (i.e. functional differences between a door and stucco are not reflected in the geometry and are therefore often ignored). With EU law now requiring energy performance certificates to be issued for all buildings, energy performance analysis becomes an increasingly important topic. Accurate, yet efficient calculation depends on simple building models. However, typical IFC models contain a lot of irrelevant data, in particular geometric representations, which are too detailed for energy performance analysis. Therefore, we propose an algorithm that extracts input models suitable for calculations directly from IFC models in a semi-automatic process. The key aspect of the algorithm is geometry simplification subject to semantic and functional groups; more specifically, the 3D representations of walls, slabs, windows, doors, etc. are reduced to a collection of surfaces describing the building's thermal shell on one hand, and the material layers associated with it on the other hand. This simplification takes into account semantic constraints and expert knowledge. Furthermore, it works on "real-world" data; i.e. it is robust towards incomplete, imperfect and inconsistent data.

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Melzer, Marianne; Damer, Naser [Betreuer]

Gesichtserkennungssoftware in Bildarchiven - Eine Untersuchung zur Nutzung von Gesichtserkennungsprogrammen für die archivische Kernaufgabe "Erschließung"

2014

Potsdam, FH, Bachelor Thesis, 2014

Diese Arbeit betrachtet zunächst die theoretischen Grundlagen für die Gesichtserkennung. Das sind zum einen Erklärungen zur Archivale Foto, auch unter dem Aspekt der Fotoarchivierung und der archivischen Erschließung und die Biometrie bzw. Biometrik. Zum anderen ist es der Ablauf der Gesichtserkennung sowie die Algorithmen, welche häufig Anwendung hierbei finden. Mit Hilfe dieser Informationen werden verschiedene Softwareprogramme einer Untersuchung, die vorab ausführlich erläutert wird, zur Nutzung von Gesichtserkennungsprogrammen für die archivische Kernaufgabe "Erschließung" unterzogen. Die Ergebnisse dieser Untersuchung sollen aufzeigen, ob und inwiefern Gesichtserkennungsprogramme eine qualitative und quantitative Verbesserung in Bezug auf die Datensicherung (Personennennung) und Vereinfachung der Erschließung in Bildarchiven erzielen könnten. Eine Empfehlung resp. ein Ausblick zu diesem Thema vollenden die Arbeit.

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Gäde, Michael; Bieber, Gerald [Betreuer]; Urban, Bodo [Betreuer]

Gestenerkennung auf Smartwatches

2014

Rostock, Univ., Studienarbeit, 2014

Virtual Environment und Smart Homes ermöglichen eine komfortable Privatsphäre. Per Fernsteuerung lassen sich Fenster öffnen, Licht an- und ausschalten, oder Zimmertemperaturen regeln. Zur bequemen und natürlichen Bedienung dieser eignen sich Sprache oder Gesten. Diese Literaturarbeit befasst sich mit den gängigen Methoden und Techniken, Handgesten zu erkennen und zu klassifizieren. Es werden einige bereits verfügbare Systeme erläutert, wozu vor allem visuelle und beschleunigungs-basierte zählen. Im Anschluss werden einige Einsatzgebiete für eine Gestensteuerung beschrieben, wobei hier der Fokus auf beschleunigungs-basierter Sensorik am Handgelenk liegt.

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Gäde, Michael; Urban, Bodo [Betreuer]; Bieber, Gerald [Betreuer]

Gestenerkennung auf Smartwatches

2014

Rostock, Univ., Bachelor Thesis, 2014

Virtual Environment und Smart Homes ermöglichen eine alternative Interaktion mit der Umgebung. Per Fernsteuerung lassen sich Fenster öffnen, Licht an- und ausschalten, oder Zimmertemperaturen regeln. Zur bequemen und natürlichen Bedienung einer solchen Steuerung eignen sich Sprache oder Gesten. Diese Bachelorarbeit befasst sich mit den gängigen Methoden und Techniken, Handgesten zu erkennen und zu klassifizieren wobei hier der Fokus auf beschleunigungs-basierter Sensorik am Handgelenk liegt. Es wird eine Gestenerkennung mit einer Smartwatch konzipiert, umgesetzt und evaluiert. Des Weiteren wird die Tauglichkeit einer permanent aktiven Erkennung überprüft.

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Hadlak, Steffen; Schumann, Heidrun [Betreuer]; Urban, Bodo [Betreuer]; Kerren, Andreas [Referent]

Graph Visualization in Space and Time

2014

Rostock, Univ., Diss., 2014

The visual analysis of graphs plays an important role in many fields and includes a diversity of aspects such as the graphs' structure and associated attributes in their spatial and temporal context. Because of their increasing size, their visualization becomes more and more difficult and necessitates a multitude of different visualization techniques. This problem becomes even more severe as with a changing analysis focus on the graph, the analyst needs to flexibly switch between different visualizations at any time. This thesis aims at solving these three challenges. First, the handling of the diversity and emerging problems are discussed exemplary for two approaches each providing a multitude of differently suited tree visualizations. Here, a family of point-based tree layouts is introduced that consists of layouts with a similar layout scheme. And an implicit tree visualization design space is derived by identifying common design decisions. For a scalable analysis of large graphs, new reduction approaches are introduced. These approached are based on the one hand on clustering techniques abstracting either the structural or temporal aspect of the graphs. And on the other hand they rely on Degree-of-Interest functions to discern interesting nodes, edges and time points. Finally, to bring the different visualizations together and thus allow a flexible analysis, novel approaches for their combination and synchronization are introduced. These approaches include the in situ visualization that is based on portals to allow a local combination of visualizations and a novel abstract overview of all aspect allowing the synchronization of multiple visualizations.

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Fietkau, Julian; Urban, Bodo [Betreuer]

Grundlagen von subjektiven Videoqualitätstests

2014

Rostock, Univ., Studienarbeit, 2014

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Hilpert, Julia; Jung, Florian [Betreuer]

Halbautomatische Segmentierung von Lymphknoten aus Magnetresonanztomographiedaten des Kopf- und Halsbereichs

2014

Mannheim, Hochschule, Bachelor Thesis, 2014

Die Größe und das Aussehen von Lymphknoten kann bei Krebspatienten Aufschluss über die Streuung eines Tumors geben. Deshalb ist ihre Vermessung bei der Behandlung sowie Nachsorge von großer Bedeutung. Der erste Schritt ist hierbei die Segmentierung der Lymphknoten. Bisher sind jedoch nur wenige Ansätze zur automatisierten Segmentierung von Lymphknoten auf MRT-Daten bekannt. In dieser Arbeit wird deshalb ein Verfahren vorgestellt, welches Lymphknoten aus MRT-Daten des Kopf- und Halsbereichs segmentiert. Diese Segmentierung findet mit minimaler Nutzerinteraktion, nur durch Setzen eines Punktes innerhalb des Lymphknotengewebes, statt. Die Hauptkomponente der gewählten Methode zur Segmentierung ist eine Wasserscheidentransformation, die das Bild über seine Gradienten in verschiedene Segmente einteilt. Mittels eines Radialstrahlverfahrens wird zusätzlich die Oberfläche des Lymphknotens angenähert. Diese Oberfläche dient nach weiteren, untergeordneten Verarbeitungsschritten dazu, aus der Menge der Bildsegmente jene auszuwählen, die den Lymphknoten repräsentieren. Evaluiert wurde das entwickelte Verfahren an 95 Lymphknoten aus 17 verschiedenen, T1- gewichteten MRT-Datensätzen. Es ergab sich ein durchschnittlicher Dice Similarity Coefficient von 0,69±0,15. Auf dem Weg zu einer vollautomatischen Segmentierung von Lymphknoten stellt das entwickelte Verfahren somit einen vielversprechenden ersten Schritt dar.

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Kahn, Svenja; Haumann, Dominik; Willert, Volker

Hand-Eye Calibration with a Depth Camera: 2D or 3D?

2014

VISAPP 2014 - Volume III

International Conference on Computer Vision Theory and Applications (VISAPP) <9, 2014, Lisbon, Portugal>

Real time 3D imaging applications such as on the fly 3D inspection or 3D reconstruction can be created by rigidly coupling a depth camera with an articulated measurement arm or a robot. For such applications, the "hand-eye transformation" between the depth camera and the measurement arm needs to be known. For depth cameras, the hand-eye transformation can either be estimated using 2D images or the 3D measurements captured by the depth camera. This paper investigates the comparison between 2D image based and 3D measurement based hand-eye-calibration. First, two hand-eye calibration approaches are introduced which differ in the way the camera pose is estimated (either with 2D or with 3D data). The main problem in view of the evaluation is, that the ground truth hand-eye transformation is not available and thus a direct evaluation of the accuracy is not possible. Therefore, we introduce quantitative 2D and 3D error measures that allow for an implicit evaluation of the accuracy of the calibration without explicitly knowing the real ground truth transformation. In view of 3D precision, the 3D calibration approach provides more accurate results on average but requires more manual preparation and much more computation time than the 2D approach.

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Sonntagbauer, Peter; Nazemi, Kawa; Sonntagbauer, Susanne; Burkhardt, Dirk

Handbook of Research on Advanced ICT Integration for Governance and Policy Modeling

2014

As governments and policy makers take advantage of information and communication technologies, leaders must understand how to navigate the ever-shifting landscape of modern technologies in order to be most effective in enacting change and leading their constituents. Advanced ICT Integration for Governance and Policy Modeling builds on the available literature, research, and recent advances in e-governance to explore advanced methods and applications of digital tools in government. This collection of the latest research in the field presents an essential reference for academics, researchers, and advanced-level students, as well as government leaders, policy makers, and experts in international relations.

  • 9781466662360
  • 1466662360
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Helper Data Scheme for 2D Cancelable Face Recognition Using Bloom Filters

2014

IWSSIP 2014. Proceedings

International Conference on Systems, Signals and Image Processing (IWSSIP) <21, 2014, Dubrovnik, Croatia>

Biometrics provide a source of automated recognition of individuals based on their physiological and behavioral characteristics. As per Directive 95/46/EC, biometric data is considered to be personal data. And according to article 8 of the European Convention on Human Rights, personal data needs to be privacy preserved. Biometric template protection mechanisms provide a privacy preserved biometric authentication. Such mechanisms assist irreversibility, revocability and unlinkability of biometric templates. Recently, a bloom filter based approach was proposed to generate irreversible iris template. In this paper, a helper data scheme for 2D cancelable face verification using bloom filters is proposed. The positions of most representative features (stable features) are used as helper data, which helps in the face recognition. The features used are extracted using Local Binary Linear Discriminant Analysis. The effect of stable features on recognition performance under scenarios of with and without using bloom filters is investigated. In addition, recognition performance after compressing multiple features into a single bloom filter is presented. The results are experimentally proved on two benchmark databases namely LFW and ORL datasets.

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Yoon, Sang Min; Graf, Holger; Kuijper, Arjan

Hierarchical Image Representation using 3D Camera Geometry for Content-based Image Retrieval

2014

Engineering Applications of Artificial Intelligence

In this paper we present a hierarchical image representation methodology by clustering images with 3D camera geometry in order to efficiently retrieve the images according to user's viewpoint. The framework of our proposed technique is composed of two steps: first the visual correlation analysis between images in a large database is determined by the estimated 3D camera geometry and second images are classified using a constrained agglomerative hierarchical image clustering method to retrieve the images the users search. The constrained agglomerative hierarchical image clustering method provides balanced hierarchical layers, independent of the number of images within the cluster. It also provides a convenient way to browsing, navigating, and categorizing of the images with various viewpoints, illumination, and partial occlusion.

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Förster, Tim; Thum, Simon [1. Gutachter]; Kuijper, Arjan [Betreuer]

Hochverfügbarkeit (Analytisch) von Big-Geo-Data als Platform as a Service

2014

Darmstadt, TU, Bachelor Thesis, 2014

Es gibt stetig wachsende Herausforderungen in der Entwicklung von Geodaten. Die Datenzunahme steigt kontinuierlich. Durch den starken Anstieg dieser Informationsansammlungen wird immer mehr Datenspeicher benötigt. Des Weiteren sollen die Systeme eine hohe Verfügbarkeit aufweisen und unter Last eine akzeptable Reaktionszeit liefern. Die Erfüllung solcher Anforderung lassen sich nur begrenzt mit einem einfachen Client/Server-System realisieren, da diese nicht gut skalieren und unter schlechten Bedingungen langsam agieren. Daher werden immer mehr Applikationen in der Cloud als Service bereitgestellt. Dies bringt viele Vorteile; unter anderem die Verbesserung der Verfügbar- und Skalierbarkeit des Services. In dieser Arbeit wird anhand eines existierenden Server-Systems die Designentscheidungen gezeigt, die für eine Realisierung des Produktes in der Cloud notwendig sind. Dieses Produkt wird dann als "Platform as a Service" bereitgestellt. Dabei werden Punkte wie, Persistierung im verteilten System und Cloud-API Gestaltung besprochen. Anschließend wird dies in einem verteilten System getestet und gegenüber ein einfaches Client/Server-System verglichen. Ebenfalls wird ein Model vorgestellt, womit die Verfügbarkeit des Systems kalkuliert wird.

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Lindstaedt, Stefanie [Betreuer]; Granitzer, Michael [Ed.]; Sack, Harald [Ed.]

i-KNOW 2014

2014

International Conference on Knowledge Technologies and Data-driven Business (I-KNOW) <14, 2014, Graz, Austria>

ACM International Conference Proceedings Series

  • 978-1-4503-2769-5
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Image-Based Bronchoscopy Navigation System Based on CT and C-arm Fluoroscopy

2014

Clinical Image-Based Procedures. Translational Research in Medical Imaging

International Workshop on Clinical Image-based Procedures (CLIP) <2, 2013, Nagoya, Japan>

Lung cancer diagnosis requires biopsy of airway tissue, which is mostly done by bronchoscopy. Although preoperative CT is available, intraoperatively only 2D information provided by the bronchoscopic camera and fluoroscopy is used. But, guidance of the bronchoscope to the target site would highly benefit from knowing the exact 3D position of the instrument inside the airways. In this paper, we present a system for preoperative planning and intraoperative navigation during bronchoscopy. The preoperative components are automatic bronchial tree segmentation and skeletonization, semi-automatic tumor segmentation and a virtual fly-through simulation for planning purposes. During the intervention, we apply C-arm pose estimation using a marker plate on the patient table to align preoperative CT and intraoperative fluoroscopy. Thus, we can calculate the current 3D position of the bronchoscope inside the bronchial tree. Evaluation of the system components on patient CT and phantom fluoroscopy images showed promising results with high accuracy and robustness.

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Le Moan, Steven; Urban, Philipp

Image-Difference Prediction: From Color to Spectral

2014

IEEE Transactions on Image Processing

We propose a new strategy to evaluate the quality of multi and hyperspectral images, from the perspective of human perception. We define the spectral image difference as the overall perceived difference between two spectral images under a set of specified viewing conditions (illuminants). First, we analyze the stability of seven image-difference features across illuminants, by means of an information-theoretic strategy. We demonstrate, in particular, that in the case of common spectral distortions (spectral gamut mapping, spectral compression, spectral reconstruction), chromatic features vary much more than achromatic ones despite considering chromatic adaptation. Then, we propose two computationally efficient spectral image difference metrics and compare them to the results of a subjective visual experiment. A significant improvement is shown over existing metrics such as the widely used root-mean square error.

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Herrmann, Daniel; Turba, Martin; Kuijper, Arjan; Schweizer, Immanuel

Inbound Interdomain Traffic Engineering with LISP

2014

Proceedings of the 39th Annual IEEE Conference on Local Computer Networks

Annual IEEE Conference on Local Computer Networks (LCN) <39, 2014, Edmonton, Canada>

Stub autonomous systems usually utilize multiple links to single or multiple ISPs. Today, inbound traffic engineering is considered hard, as there is no direct way to influence routing decisions on remote systems with BGP. Current traffic engineering methods built on top of BGP are heuristic and time-consuming. The Locator/Identifier Separation Protocol (LISP) promises to change that. In this paper, we conduct the first comprehensive evaluation of LISP and its built-in traffic engineering methods on a real-world testbed. First, we compare LISP to plain BGP and BGP advertising more specific prefixes. This comparison shows that LISP allows effective load-balancing with an accuracy of approximately 5%, while being easier to configure than BGP and its variants. Further experiments show that these results are independent from the number of concurrent streams.

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Dutz, Tim; Majewski, Martin; Müller, Stefanie; Braun, Andreas; Konert, Johannes; Kamieth, Felix; Rieß, Henrik; Carl, Antonija Mrsic; Bender, Denise; Brückner, Verena; Klein, Peter; Wichert, Reiner; Göbel, Stefan; Steinmetz, Ralf

inDAgo - ein Mobilitätsunterstützungssystem für Senioren auf dem Weg in die Praxis

2014

Wohnen - Pflege - Teilhabe. Besser leben durch Technik

Ambient Assisted Living (AAL) <7, 2014, Berlin, Germany>

Inklusion und soziale Teilhabe sind zentrale Themen in der Ambient Assisted Living (AAL) Forschung und eine Voraussetzung für soziale Teilhabe ist Mobilität. Im Rahmen der Initiative "Mobil bis ins hohe Alter" fördert das Bundes-ministerium für Bildung und Forschung (BMBF) verschiedene nationale Forschungsprojekte, die zum Ziel haben, Mobilitätsunterstützungssysteme für Senioren zu entwickeln. Eines dieser Projekte ist das inDAgo-Projekt, das im Herbst 2013 kurz vor der Vorstellung seiner Ergebnisse steht. In diesem Beitrag präsentieren wir das Konzept von inDAgo und den aktuellen Entwicklungsstand des Systems.

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Industrie 4.0 - Evolution statt Revolution

2014

wt Werkstattstechnik online

Der Industrie stehen große Änderungen bevor: Künftig stimmen sich die Produktionsanlagen untereinander ab und steuern sich selbst, die Produkte wissen, wo sie sich befinden und was ihnen zum fertigen Artikel noch fehlt. Die Basis für diese Industrie der Zukunft wird am Fraunhofer IGD mithilfe des "Visual Computings" gelegt.

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Information Visualization and Policy Modeling

2014

Handbook of Research on Advanced ICT Integration for Governance and Policy Modeling

Policy design requires the investigation of various data in several design steps for making the right decisions, validating, or monitoring the political environment. The increasing amount of data is challenging for the stakeholders in this domain. One promising way to access the "big data" is by abstracted visual patterns and pictures, as proposed by information visualization. This chapter introduces the main idea of information visualization in policy modeling. First abstracted steps of policy design will be introduced that enables the identification of information visualization need in the entire policy lifecycle. Thereafter the foundations of information visualization will be introduced based on an established reference model. We aim to amplify the incorporation of information visualization in the entire policy design process. Therefore the aspects of data and human interaction will be introduced too. The foundation leads to description of a conceptual design for social data visualization, whereas the aspect of semantics plays an important role.

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Hoßbach, Martin; Sakas, Georgios [Referent]; Fellner, Dieter W. [Betreuer]

Integrierte miniaturisierte Kameras zur Instrument- und Zielfindung in medizinischen Anwendungen

2014

Darmstadt, TU, Diss., 2014

Im Bereich der Mikroelektronik hat in den vergangenen Jahrzehnten eine rasante technische und technologische Entwicklung stattgefunden, die neben den offensichtlichen Auswirkungen auf das tägliche Leben auch die Werkzeuge der Ärzte beeinflusst hat. Ein Beispiel dafür sind Trackingverfahren, die vielfältig und erfolgreich in der Medizin Anwendung finden und eine Reihe von neuen Behandlungstechniken ermöglicht haben. In medizinischen Anwendungen kommen verschiedenste Trackingsysteme zum Einsatz. Häufig sind es magnetische und optische Trackingsysteme. Beide haben im OP-Umfeld Nachteile: magnetische Trackingsysteme reagieren empfindlich auf Metalle, die im OP häufig vorkommen; optische Trackingsysteme sind wegen der Line-of-Sight-Problematik im OP umständlich zu benutzen. Allgemein sind diese Systeme häufig teuer in der Anschaffung und rechtfertigen bisweilen, verglichen mit den Kosten des jeweiligen Eingriffs, ihren Einsatz nicht. Demgegenüber steht der aktuelle Trend der Miniaturisierung. Kameras werden derzeit immer kleiner und preiswerter. Es wird daher die These aufgestellt, dass die Nachteile von bisherigen Trackingsystemen in bestimmten medizinischen Anwendungen durch die Verwendung miniaturisierter Kameras ausgeglichen werden können, weil diese deutlich dichter am Ort des Geschehens positioniert werden können. Dadurch fällt auch eine unter Umständen schlechtere Bildqualität (im Vergleich zu präzisen Trackingkameras) nicht ins Gewicht. Diese These wird exemplarisch an zwei Anwendungen untersucht. Es wird ein MRT-kompatibles optisches Kopftrackingsystem entwickelt, das die Kopfbewegung eines Patienten mit Hilfe von runden, planaren, einfarbigen Markern auf der Stirn des Patienten verfolgt. Dafür werden Kameras verwendet, die im Innern des Tomografen mit einer Halterung an der Kopfspule befestigt werden. Algorithmen, die in Infrarot-Trackingsystemen Verwendung finden, mussten wegen der Bildqualität der Kameras, den klinischen Anforderungen (Belästigung des Patienten und Belastung des Personals) und den Gegebenheiten im MR-Tomograf teilweise angepasst werden. Für dieses Trackingsystem wurde ein Kreuzkalibrierverfahren entwickelt, das aus wassergefüllten Kugeln ein virtuelles Kalibrierphantom bildet. Es unterscheidet sich damit von bekannten Verfahren, bei denen bei der Kreuzkalibrierung die verwendeten Strukturen, die im MRT-Bild sichtbar sind, und die Strukturen, die im Kamerabild sichtbar sind, unterschiedlich sind. Entsprechende Kalibrierphantome müssen also aufwändig hergestellt oder präzise vermessen werden. Das Trackingsystem wurde theoretisch, praktisch im Labor und klinisch im Probandenversuch evaluiert. Im Rahmen eines klinischen Projektes, bei dem über einen sehr langen Zeitraum wiederholt MRTAufnahmen mit niedriger Auflösung gemacht wurden, konnte mit dem Trackingsystem eine virtuelle Immobilisation erreicht werden. Weiterhin wurde ein Navigationssystem für die ultraschallgesteuerte Punktion entwickelt. Der Arzt wird dabei durch die Visualisierung des Verlaufs der Nadel im Ultraschallbild bei der Punktion unterstützt. Dafür wurde ein Nadeltrackingsystem entwickelt, das aus zwei preiswerten Kameras besteht, die am Schallkopf befestigt sind. Aus den Bildern der Kameras wird kantenbasiert die Nadel extrahiert, ihr Verlauf relativ zum Ultraschallkopf ermittelt, und Verlauf und Schnittpunkt der Nadel mit dem Ultraschallbild dargestellt. Das Navigationssystem wurde sowohl theoretisch als auch praktisch im Labor am Phantom evaluiert. Daran waren Ärzte beteiligt, die entsprechende Eingriffe in ihrem Arbeitsalltag durchführen. Es konnte gezeigt werden, dass die Genauigkeit gegenüber dem Stand der Technik verbessert werden konnte.

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Landesberger, Tatiana von; Fiebig, Sebastian; Bremm, Sebastian; Kuijper, Arjan; Fellner, Dieter W.

Interaction Taxonomy for Tracking of User Actions in Visual Analytics Applications

2014

Handbook of Human Centric Visualization

In various application areas (social science, transportation, or medicine) analysts need to gain knowledge from large amounts of data. This analysis is often supported by interactive Visual Analytics tools that combine automatic analysis with interactive visualization. Such a data analysis process is not streamlined, but consists of several steps and feedback loops. In order to be able to optimize the process, identify problems, or common problem solving strategies, recording and reproducibility of this process is needed. This is facilitated by tracking of user actions categorized according to taxonomy of interactions. Visual Analytics includes several means of interaction that are differentiated according to three fields: information visualization, reasoning, and data processing. At present, however, only separate taxonomies for interaction techniques exist in these three fields. Each taxonomy covers only a part of the actions undertaken in Visual Analytics. Moreover, as they use different foundations (user intentions vs. user actions) and employ different terminology, it is not clear to what extent they overlap and cover the whole Visual Analytics interaction space. We therefore first compare them and then elaborate a new integrated taxonomy in the context of Visual Analytics. In order to show the usability of the new taxonomy, we specify it on visual graph analysis and apply it to the tracking of user interactions in this area.

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Graf, Holger; Larson, Mats; Stork, André

Interactive 3D Subdomaining using Adaptive FEM based on Solutions to the Dual Problem

2014

Proceedings of the 2014 Virtual Reality International Conference

Virtual Reality International Conference (VRIC) <16, 2014, Laval, France>

This paper presents a new technique for automatic, interactive 3D subdomaining coupled to mesh and simulation refinements in order to enhance local resolutions of CAE domains. Numerical simulations have become crucial during the product development process (PDP) for predicting different properties of new products as well as the simulation of various kinds of natural phenomena. "What-if-scenarios" and conceptual changes to either the boundary or the domain are time consuming and cost intensive. Most of the time, engineers are interested in a deeper understanding of local quantities rather than being exposed to an iterative re-simulation of the overall domain. New techniques for automatic and interactive processes are then challenged by the cardinality and structural complexity of the CAE domain. This paper introduces a new interactive technique that automatically reduces the analysis space, and allows engineers to enhance the resolution of local problems without a need for recalculating the global problem. The technique, integrated into a VR based front end, achieves faster reanalysis cycles compared with traditional COTS tool chains and engineering workflows.

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Schiel, Ralf; Bieber, Gerald; Vahl, Tobias

InterLearn* - Interaktives Lernen und telemedizinische Nachsorge bei Kindern und Jugendlichen mit Übergewicht und Adipositas

2014

Diabetologie und Stoffwechsel

Diabetes Kongress (DDG) <49, 2014, Berlin, Germany>

Einleitung: Übergewicht und Adipositas sind Risikofaktoren für eine Reihe von Folgekrankheiten (darunter Diabetes mellitus) und stellen somit zunehmende medizinische und sozio-ökonomische Belastungen dar. Zur Behandlung stehen strukturierte Behandlungs- und Schulungsprogramme (SBSP) zur Verfügung. Aufgrund häufig fehlender Strukturen für eine effektive, langfristige Nachsorge nach Teilnahme am SBSP liegt der Loss-to-follow-up aber bei ca. 70% (Effektivitätsverlust). Ein neuer Lösungsansatz für eine effiziente und effektive Nachsorge besteht im Einsatz von interaktiven, telemedizinischen Technologien. Dieser Ansatz wird in der vorliegenden Studie analysiert. Methoden: 60 Kinder/Jugendliche, 10 - 18 Jahre (Power Analyse: 2-seitig, Effect size d = 1, Irrtumswahrscheinlichkeit ?= 0,05, Power [1-? err prob]= 0,95, Allocation N2/N1 = 1, Ergebnis: Sample-size Gruppe 1/2: n = 27/n = 27), BMI-SDS> 90. Perzentile, werden randomsiert zu einer Interventions- (Anwendung von InterLearn, eines computergestützten Monitoring-, Informations- und Trainingsprogramms, Fraunhofer Institut für Graphische Datenverarbeitung) oder Kontrollgruppe (herkömmliches SBSP ohne Telemedizin). Die Auswertung erfolgt am Ende einer 6-wöchigen Rehabilitation und nach 12-monatiger ambulanter Nachbetreuungsphase. Ergebnisse: Bis zum 31.12.2013 wurden 29 Patienten randomsiert (bei Aufnahme mittleres Gewicht 88,3 ± 21,3 kg, BMI 31,2 ± 5,1 kg/m2). Bis zum Ende des stationären Aufenthaltes ergab sich eine Reduktion von Gewicht (82,6 ± 19,4 kg, p < 0,001) und BMI (29,2 ± 4,4 kg/m2, p < 0,001). Es bestanden signifikante Unterschiede (p < 0,05) zwischen Interventions- und Kontrollgruppe. Die Akzeptanz der telemedizinischen Unterstützung während der stationären, aber auch ambulanten Nachbetreuung war sehr hoch (> 70%). Schlussfolgerungen: Die vorläufigen Ergebnisse belegen, dass eine telemedizinische Unterstützung zur Gewichtsreduktion bei Kindern und Jugendlichen mit Übergewicht und Adipositas in Kurz- und langristiger Nutzung effektiv sein kann. *Das Projekt InterLearn wird mit Unterstützung durch diabetesDE, Charity-Gala 2012, durchgeführt.

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Fellner, Dieter W. [Betreuer]; Baier, Konrad [Betreuer]; Ackeren, Janine van [Red.]; Bornemann, Heidrun [Red.]; Wehner, Detlef [Betreuer]

Jahresbericht 2013

2014

Die Forscher des Fraunhofer-Instituts für Graphische Datenverarbeitung IGD machen aus Informationen Bilder und aus Bildern Informationen. Die bild- und modellbasierte Informatik nennt man "Visual Computing". Hierzu zählen Graphische Datenverarbeitung, Computer Vision sowie Virtuelle und Erweiterte Realität. Mithilfe des Visual Computing werden Bilder, Modelle und Graphiken für alle denkbaren computerbasierten Anwendungen verwendet, erfasst und bearbeitet. Dabei setzen die Forscherinnen und Forscher graphische Anwendungsdaten in Wechselbeziehung mit nicht graphischen Daten, was bedeutet, dass sie Bilder, Videos und 3D-Modelle mit Texten, Ton und Sprache rechnergestützt anreichern. Daraus ergeben sich wiederum neue Erkenntnisse, die in innovative Produkte und Dienstleistungen umgesetzt werden können. Dafür werden entsprechend fortgeschrittene Dialogtechniken entworfen. Durch seine zahlreichen Innovationen hebt das Fraunhofer IGD die Interaktion zwischen Mensch und Maschine auf eine neue Ebene.

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Maus, Steffen; Kuijper, Arjan [Betreuer]; Rus, Silvia [Betreuer]

Klassifizierung von Liegepositionen mittels kapazitiver Näherungssensorik

2014

Darmstadt, TU, Bachelor Thesis, 2014

In den vergangenen Jahren hat die Verwendung von kapazitiver Sensorik in kleinen elektronischen Endgeräten stark zugenommen, zudem spielt sie auch bei Ubiquitous Computing immer mehr eine bedeutende Rolle. Im Bezug auf die Reichweite der Sensorik ist es mittlerweile möglich, auf Objekte in einer Entfernung von bis zu 50 cm zu reagieren. Diese Bachelorarbeit behandelt die Klassifizierung von Liegepositionen mittels kapazitiver Sensorik. Das Hauptaugenmerk liegt dabei auf Anwendungsfällen aus der Medizin und der Analyse, wie zuverlässig ein solches System die Liegepositionen von Patienten erkennt. Zum Erlangen der Rohdaten befindet sich auf der Matratze Bettlaken mit einem groben Gitter aus Elektroden, wodurch an jedem Schnittpunkt des Gitters ein kapazitiver Wert gemessen werden kann. Die Rohdaten aus diesem Versuchsaufbau werden zur Klassifizierung der Liegeposition verwendet.

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Bieber, Gerald; Wacker, Fred; Haescher, Marian; Alm, Rebekka

Konzept zur Arbeitsgeräteerkennung mittels Vibrationsanalyse durch Methoden des maschinellen Lernens

2014

WIWITA 2014. Proceedings

Wismarer Wirtschaftsinformatiktage (WIWITA) <9, 2014, Wismar, Germany>

Die Verwendung verschiedenster Arbeitsgeräte unterstützt den Arbeiter bei seiner Tätigkeit und ist im industriellen Umfeld nicht mehr wegzudenken. Viele elektrisch oder pneumatisch betriebene Arbeitsgeräte erzeugen im Betrieb Vibrationen, die auf den Anwender übertragen werden. Überschreiten diese über längere Zeit ein gewisses Maß, kann dieses langfristig zu Beeinträchtigungen und Schädigungen bis hin zur Berufsunfähigkeit führen. Entsprechend der Lärm- und Vibrations-Arbeitsschutzverordnung ist an Arbeitsplätzen mit potentieller Exposition gegenüber Vibrationen eine laufende Gefährdungsanalyse vorgeschrieben. In der Praxis geschieht dies derzeit stichprobenartig durch externe Experten oder behelfsmäßig anhand von Zeitschätzungen und Tabellenwerten. In der einschlägigen Literatur wird darauf verwiesen, dass die tatsächliche Exposition dabei häufig überschätzt wird, wodurch den betroffenen Unternehmen ein finanzieller Schaden entsteht. In der vorliegenden Arbeit wird ein Konzept vorgestellt, um Hand-Arm-Vibrationen durch eine handelsübliche Smartwatch abzuschätzen. Dabei werden durch verschiedene Sensoren der Smartwatch die Beschleunigungskräfte (Akzelerometer), die Winkeländerungen (Gyroskop) sowie die Geräusche (Mikrofon) gemessen. Mit Methoden des maschinellen Lernens können auf dieser Grundlage die verwendeten Arbeitsgeräte sowie die genaue Nutzungsdauer bestimmt werden. Auf diese Weise wird mit preisgünstiger COTS-Hardware eine wesentlich genauere Bewertung vibrationsbedingter Gefährdungen am Arbeitsplatz möglich. Das System kann den Träger bei zu hoher Vibrationsbelastung selbstständig warnen. Darüber hinaus können die durchgeführten Arbeiten bei der Ausführung automatisch oder manuell annotiert werden. Um die grundlegende Machbarkeit des Konzeptes zu überprüfen, wurden unter Verwendung von Arbeitsgeräten aus sechs Geräteklassen mit 13 Probanden Messdaten erhoben und mit dem beschriebenen Verfahren analysiert. Dabei zeigte sich zunächst, dass der Gebrauch stark vibrierender Arbeitsgeräte mit hoher Präzision von Inaktivität abgegrenzt werden kann, wodurch eine Zeiterfassung der Gerätenutzung ermöglicht wird. Darüber hinaus konnten im Laborumfeld einzelne Werkzeuge auch zwischen verschiedenen Probanden wiedererkannt werden. Die Einsatzfähigkeit unter praxisnahen Bedingungen muss jedoch in weiteren Arbeiten untersucht werden.

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Nesterenko, Dmitrijs; Aehnelt, Mario [Betreuer]; Urban, Bodo [Betreuer]

Konzepte, Methoden und Technologien für eine mobile und situative Informationsverteilung auf verteilten Displays

2014

Rostock, Univ., Studienarbeit, 2014

Bei der Montage von Maschinen und Anlagen werden Informationen über Aufträge, konstruktive oder verfahrenstechnische Details sowie zu verarbeitende Bauteile und Materialien benötigt. Zur Sicherstellung ihrer Aktualität sind digitale Technologien für die Bereitstellung und Darstellung der Informationen am stationären, teil-stationären und mobilen Arbeitsplatz erforderlich. Umgebungen, die mit den Technologien ausgestattet sind, sollen die Information so verteilen, dass die Erfassung und Verarbeitung der Informationen durch den Montagearbeiter den Montageprozess nicht zusätzlich behindert sondern unterstützt. Je nach Ausstattung und Arbeitssituation ist die Informationsverteilung unterschiedlich. Im Rahmen dieser Literaturarbeit soll eine Literaturrecherche durchgeführt werden. In der Recherche sollen schon vorhandene Konzepte, Methoden und Technologien für die Informationsverteilung auf verteilten Displays untersucht werden.

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Fastnacht, Claas; Urban, Bodo [Betreuer]; Aehnelt, Mario [Betreuer]

Konzepte, Methoden und Werkzeuge für eine Unterstützung kooperativer Arbeitsprozesse in der Montage

2014

Rostock, Univ., Studienarbeit, 2014

Bei der Montage von Maschinen und Anlagen kommen fast immer Teams zum Einsatz. Hierbei ist es wichtig, Informationen möglichst schnell an alle Beteiligten weiterzuleiten um Verzögerungen, Störungen und Unfälle zu vermeiden. Mit dem Aufkommen verhältnismäßig günstiger und einfach zu bedienender mobiler Endgeräte ist es nun möglich, Teile der Kommunikation über diese Geräte abzuwickeln und auch komplexe Informationen wie Baupläne, Konstruktionszeichnungen, 3D-Modelle und Montageanweisungen darzustellen. Zusätzlich zu der offiziellen Kommunikation kann auch die informelle Kommunikation in Form von Anmerkungen, Skizzen und Ähnlichem den Arbeitern wichtige Hinweise zur korrekten und/ oder schnelleren Ausführung ihrer Aufgaben geben. Dadurch lassen sich die Kosten durch Ausfälle, Wartezeiten und Bedienfehler reduzieren, sowie die Kundenzufriedenheit durch eine schnellere und termingerechtere Ausführung erhöhen. Um diese Ziele zu erreichen ist jedoch auch eine hohe Akzeptanz bei allen Beteiligten wichtig. Selbst die besten Geräte und Programme verfehlen ihr Ziel, wenn sie nicht genutzt werden. Diese Arbeit versucht, den aktuellen Stand der Technik und Wissenschaft darzustellen und hinsichtlich der Eignung für ein später zu erarbeitendes Konzept zu bewerten. Neben den technischen und wirtschaftlichen Aspekten (Leistung, Kosten, etc.) werden auch arbeitspsychologische Aspekte miteinbezogen. Außerdem werden kurz bereits vorhandene Konzepte und Produkte vorgestellt.

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Lerch, Patrick; Landesberger, Tatiana von [1. Gutachterin]; Kuijper, Arjan [Betreuer]

Layoutalgorithmus für Visualisierung von Mustern in Ausfalleffektgraphen

2014

Darmstadt, TU, Bachelor Thesis, 2014

Heutzutage werden immer mehr und größere Datenmengen abgespeichert und verarbeitet. Abhängigkeiten zwischen diesen Daten können durch gerichtete Graphen visualisieren werden. Mit Hilfe von Graphen besteht die Möglichkeit, Ausfallsimulationen für einzelne Knoten durchzuführen, um den Dominoeffekt, der durch den Ausfall dieses einen Knotens entsteht, abzuschätzen. Durch solch eine Simulation entsteht der Ausfalleffektgraph, welcher sich besonders gut in einem hierarchischen Layout darstellen lässt. Die ordentliche Darstellung eines solchen gerichteten hierarchischen Graphen erfordert einen guten Algorithmus zur Minimierung der Kantenkreuzungen. Mit beispielsweise der Barycenter, Median oder Sifting Heuristik existieren für dieses Problem schon eine große Vielzahl an unterschiedlichsten Algorithmen. Jedoch spezialisiert sich noch keiner dieser Verfahren auf das planare Darstellen einzelner Blöcke, Subgraphen oder Muster bei der Kantenkreuzungsreduktion. Diese Arbeit adressiert genau dieses Problem. Hauptkriterium dieser Thesis ist vorher definierte Subgraphen, Blöcke oder Muster bei der Minimierung der Kantenkreuzungen zu präferieren und trotzdem noch die Anzahl an Kantenkreuzungen im Gesamtgraphen minimal zu halten.

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Lean In or Lean Back? Aspects on Interactivity & Mediation in Handheld Augmented Reality in the Museum

2014

GCH 2014. Short Papers - Posters

Eurographics Symposium on Graphics and Cultural Heritage (GCH) <12, 2014, Darmstadt, Germany>

With the idea to design augmented reality experiences that attract and inform, and which are also seamlessly incorporated into interactive museum narratives, this paper explores finding the appropriate balance between attraction, interactivity and information mediation from the user's point of view. Within the scope of research project CHESS, we've implemented techniques that fuse interaction and mediation to enrich visits to cultural institutions by visual means and AR specific interactions. While it is AR's wow-effect that attracts, our findings show that users far too often struggle to cope with the system and interactivity instead of focusing on the information presentation in AR. We discuss our results of finding the right balance between interactive (lean-in) and non-interactive (lean-back) presentation and interaction techniques in AR.

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Wächter, Michael; Moehrle, Nils; Goesele, Michael

Let There Be Color! Large-Scale Texturing of 3D Reconstructions

2014

Computer Vision - ECCV 2014. Proceedings Part V

European Conference on Computer Vision (ECCV) <13, 2014, Zurich, Switzerland>

3D reconstruction pipelines using structure-from-motion and multi-view stereo techniques are today able to reconstruct impressive, large-scale geometry models from images but do not yield textured results. Current texture creation methods are unable to handle the complexity and scale of these models. We therefore present the first comprehensive texturing framework for large-scale, real-world 3D reconstructions. Our method addresses most challenges occurring in such reconstructions: the large number of input images, their drastically varying properties such as image scale, (out-of-focus) blur, exposure variation, and occluders (e.g., moving plants or pedestrians). Using the proposed technique, we are able to texture datasets that are several orders of magnitude larger and far more challenging than shown in related work.

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Leveraging Public Participation in Urban Planning with 3D Web Technology

2014

Proceedings Web3D 2014

International Conference on 3D Web Technology (WEB3D) <19, 2014, Vancouver, BC, Canada>

In this paper we present a web-based platform that makes use of HTML5 technology and WebGL to facilitate public participation in urban planning. It consists of components that enable city administrations to present urban plans to the public and to engage with stakeholders. One of these components uses the open source library X3DOM to visualise 3D content-for example, a city model containing a 3D representation of a planned building. Since X3DOM does not need additional software to be installed on the user's system our implementation is more portable than previous work. Our solution is based on the open source software Liferay which allows it to be configured for various urban planning projects. In order to enable communication between different web application components residing in inline frames (iframes) we implemented a special message bus based on HTML5 postMessage. In this paper we describe implementation details, but we also intensively discuss the possibilities of modern web technology for urban planning. We motivate the use of such technology through three examples that can be implemented using our web application. In this paper we also present results from evaluating our application in user workshops carried out within the project urbanAPI that is funded by the European Commission. Finally, we draw conclusions and discuss possibilities for future urban planning use cases.

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Liver Segmentation in Contrast Enhanced MR Datasets Using a Probabilistic Active Shape and Appearance Model

2014

IEEE 27th International Symposium on Computer-Based Medical Systems

IEEE Symposium on Computer-Based Medical Systems (CBMS) <27, 2014, New York, NY, USA>

The current standard for diagnosing liver tumors is contrast-enhanced multiphase computed tomography. On this basis, several software tools have been developed by different research groups worldwide to support physicians for example in measuring remnant liver volume, analyzing tumors, and planning resections. Several algorithms have been developed to perform these tasks. Most of the time, the segmentation of the liver is at the beginning of the processing chain. Therefore, a vast amount of CT-based liver segmentation algorithms have been developed. However, clinics slowly move from CT as the current gold standard for diagnosing liver diseases towards magnetic resonance imaging. In this work, we utilize a Probabilistic Active Shape Model with an MR specific preprocessing and appearance model to segment the liver in contrast enhanced MR images. Evaluation is based on 8 clinical datasets.

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Bieber, Gerald; Kirste, Thomas; Gäde, Michael

Low Sampling Rate for Physical Activity Recognition

2014

Proceedings of the 7th International Conference on PErvasive Technologies Related to Assistive Environments

ACM International Conference on PErvasive Technologies Related to Assistive Environments (PETRA) <7, 2014, Rhodes Island, Greece>

The monitoring of physical activity by acceleration sensors is very common. Smartphones and it´s accessories (Smartwatch, wrist bands) are equipped with sensors and provide enough calculation power for data processing. Body worn mobile devices are recognizing various types of physical activities. The current concept consists of a very high sampling rate, the higher the sampling rate, the better the accuracy of classification. This strategy reduces the battery lifetime, especially for devices with limited physical dimensions, e.g. Smartwatches. Since sampling rate is a relevant factor for energy consumption, this work is analyzing the possibilities and performance of a very low sampling rate for physical activity recognition on Smartwatches. This work proposes the new concept of extremely low sampling rate for physical activity recognition.

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Lukas, Uwe von; Vahl, Matthias; Mesing, Benjamin

Maritime Applications of Augmented Reality - Experiences and Challenges

2014

Virtual Augmented and Mixed Reality. Applications of Virtual and Augmented Reality. Proceedings Part II

International Conference Virtual Augmented and Mixed Reality (VAMR) <6, 2014, Heraklion, Crete, Greece>

The paper summarizes experiences from applied research in visual computing for the maritime sector. It starts with initial remarks on Augmented Reality in general and the specific boundary conditions of the maritime industry. The focus is on a presentation of various concrete AR applications that have been implemented for use cases in maritime engineering, production, operation and retrofitting. The paper closes with remarks on future research in this area.

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Puhl, Julian; Kuijper, Arjan [Betreuer]; Knuth, Martin [Betreuer]

Materialsysteme für das realistische Echtzeit-Rendering von Szenen in Anwesenheit von Flüssigkeitssimulationen und Image-Based Lighting

2014

Darmstadt, TU, Bachelor Thesis, 2014

Für eine Simulation einer Flüssigkeit in Echtzeit werden aktuell Verfahren angewandt, die entweder das Modell diskretisieren und somit gitterbasiert arbeiten oder die einzelnen Atome zu größeren Partikeln zusammenfassen und so das Verhalten simulieren. Beiden Ansätzen ist gemein, dass als Ergebnis keine glatte Oberfläche vorliegt, sondern eine angenäherte, die uneben ist, aus vielen einzelnen Elementen besteht und zudem keine optischen Eigenschaften einer Flüssigkeit besitzt. Aus Zeitgründen darf die nachfolgende Generierung der Oberfläche nicht sehr zeitaufwendig sein. Aus diesem Grund wird in dieser Arbeit die Nachbearbeitung der Daten via Bildverarbeitung unter der Anwendung von Glättungsfiltern sowie einer Bildpyramide untersucht. Die Pyramide bietet Zugriff auf verschiedene Detailstufen. Hierdurch können unterschiedliche Glättungen in Abhängigkeit von der Entfernung zum Betrachter gewählt werden. Viele Verfahren filtern hier sehr stark und fügen nachträglich wieder ein Rauschen ein, um eine nicht ganz so glatte Oberfläche zu simulieren. In Szenen, bei denen die simulierte Flüssigkeit seitlich betrachtet wird, können sowohl nahe als auch weiter entfernte Partikel nahe beieinander existieren. Hier spielt das Verfahren seine Stärke aus gleichzeitig auf unterschiedlich stark gefilterte Werte zugreifen zu können.

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Dekker, Niels; Lucassen, Marcel; Kirchner, Eric; Urban, Philipp; Huertas, Huertas

Mathematical Limitations when Choosing Psychophysical Methods: Geometric Versus Linear Grey Scales

2014

Measuring, Modeling, and Reproducing Material Appearance

Measuring, Modeling, and Reproducing Material Appearance (MMRMA) <1, 2014, San Francisco, CA, USA>

The grey scale method is commonly used for investigating differences in material appearance. Specifically, for testing color difference equations, perceived color differences between sample pairs are obtained by visually comparing to differences in a series of achromatic sample pairs. Two types of grey scales are known: linear and geometric. Their instrumental color differences vary linearly or geometrically (i.e., exponentially), respectively. Geometric grey scales are used in ISO standards and standard procedures of the textile industries.

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Measuring Context Relevance for Adaptive Semantics Visualizations

2014

i-KNOW 2014

International Conference on Knowledge Technologies and Data-driven Business (I-KNOW) <14, 2014, Graz, Austria>

Semantics visualizations enable the acquisition of information to amplify the acquisition of knowledge. The dramatic increase of semantics in form of Linked Data and Linked-Open Data yield search databases that allow to visualize the entire context of search results. The visualization of this semantic context enables one to gather more information at once, but the complex structures may as well confuse and frustrate users. To overcome the problems, adaptive visualizations already provide some useful methods to adapt the visualization on users' demands and skills. Although these methods are very promising, these systems do not investigate the relevance of semantic neighboring entities that commonly build most information value. We introduce two new measurements for the relevance of neighboring entities: The Inverse Instance Frequency allows weighting the relevance of semantic concepts based on the number of their instances. The Direct Relation Frequency inverse Relations Frequency measures the relevance of neighboring instances by the type of semantic relations. Both measurements provide a weighting of neighboring entities of a selected semantic instance, and enable an adaptation of retinal variables for the visualized graph. The algorithms can easily be integrated into adaptive visualizations and enhance them with the relevance measurement of neighboring semantic entities. We give a detailed description of the algorithms to enable a replication for the adaptive and semantics visualization community. With our method, one can now easily derive the relevance of neighboring semantic entities of selected instances, and thus gain more information at once, without confusing and frustrating users.

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Happel, Kathrin; Dörsam, Edgar; Urban, Philipp

Measuring Isotropic Subsurface Light Transport

2014

Optics Express

Subsurface light transport can affect the visual appearance of materials significantly. Measuring and modeling this phenomenon is crucial for accurately reproducing colors in printing or for rendering translucent objects on displays. In this paper, we propose an apparatus to measure subsurface light transport employing a reference material to cancel out adverse signals that may bias the results. In contrast to other approaches, the setup enables improved focusing on rough surfaces (e.g. uncoated paper). We derive a measurement equation that may be used to deduce the point spread function (PSF) of subsurface light transport. Main contributions are the usage of spectrally-narrowband exchangeable LEDs allowing spectrally-resolved measurements and an approach based on quadratic programming for reconstructing PSFs in the case of isotropic light transport.

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Segovia, Maria V. Ortiz [Ed.]; Urban, Philipp [Betreuer]; Allebach, Jan P. [Ed.]

Measuring, Modeling, and Reproducing Material Appearance

2014

Measuring, Modeling, and Reproducing Material Appearance (MMRMA) <1, 2014, San Francisco, CA, USA>

Proceedings of SPIE

The main topics encountered on the papers of this document correspond to any of the following categories: Methods for measuring material properties: measurement of Bidirectional Reflectance Distribution Functions (BRDF), Bidirectional Texture Functions (BTF) and Bidirectional Surface Scattering Reflectance Distribution Function (BSSRDF); estimation of material difference perception; evaluation of metallic coatings/inks; measurement of glossiness; estimation of texture perception; data acquisition methods for different types of materials. Models for distinct characteristics of materials: modeling of Bidirectional Reflectance Distribution Functions (BRDF), Bidirectional Texture Functions (BTF) and Bidirectional Surface Scattering Reflectance Distribution Function (BSSRDF); modeling material difference perception; appearance modeling of glossiness and texture; modeling of varnish and special effects inks; softproofing methods for 2.5D and 3D printing. Material reproduction aspects: quality evaluation of 2.5D and 3D soft- and hardcopy reproductions (display and printing); estimation of effects of environmental aspects in material perception (lighting, observers' position, printing media); estimation of sensory input (visual, touch, audio) effect in material perception; evaluation of aesthetic aspects of 2.5D and 3D soft- and hard-copy reproductions (display and printing); saliency of 2.5D and 3D soft- and hard-copy reproductions (display and printing); imaging and perception of metallic and effect coatings/inks; saliency, quality, and aesthetics in appearance reproduction; spectral reproduction.

  • 9780819499356
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Mesh Partitioning for Parallel Garment Simulation

2014

WSCG 2014. Communication Papers Proceedings

International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision (WSCG) <22, 2014, Plzen, Czech Republic>

We present a method for partitioning meshes that allows a simple and efficient parallel implementation of different simulation methods. It is based on a generalization of the concept of independent sets from graph theory to sets of simulation elements. The general description makes it versatile and flexibly applicable in existing simulation systems. Every simulation method that formerly worked by sequentially processing a set of simulation elements can now be parallelized by partitioning the underlying set, without affecting the behavior of the simulated model.

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Kopp, Manuel Georg Maria; Kuijper, Arjan [Betreuer]; Bremm, Sebastian [Betreuer]; Landesberger, Tatiana von [Betreuerin]

Methoden und visuell interaktive Werkzeuge zur automatischen Generierung von Graphen mit geografischem Bezug

2014

Darmstadt, TU, Master Thesis, 2014

Analyse oder Simulation von Zuliefernetzwerken werden oftmals durch grafische Darstellungen unterstützt. Dafür werden die Erstellung der Lieferstrukturen sowie die GEO-Position der einzelnen Lieferanten benötigt. Die Generierung der zugehörigen Graphen mit geografischem Bezug sollte nach Möglichkeit weitestgehend automatisiert erfolgen. Eine automatisierte Verortung steht Graphengeneratoren derzeit nicht zur Verfügung. Es kann daher sehr zeitaufwändig sein, wenn die Verortung eines Knotens verändert wird. Bei den aktuellen Verfahren müssen alle mit diesem Knoten verbundenen Knoten manuell auf ihre Lokalisation überprüft und ggf. manuell angepasst werden. In dieser Arbeit wird ein Weg aufgezeigt Graphen mit geografischem Bezug zu generieren, um diese manuellen Überprüfungen und Anpassungen zu automatisieren. Um dies zu erreichen wurde eine Datenbasis aus öffentlich zugänglichen Daten generiert. Diese beinhaltet eine politisch basierte hierarchische Aufteilung der Welt, aus der generierte Knoten automatisch verortet werden. Darüber hinaus wurden Regeln definiert, um statische Beziehungseigenschaften von Knoten zu ersetzen. Auf diese Weise werden Struktur-, Knoten- oder Kanteneigenschaften des zu erstellenden Graphen mit geografischem Bezug festgelegt. Die Regeln können interaktiv unter Verwendung einer Visualisierung manipuliert werden. Dadurch ist es möglich generisch verschiedene Graphen mit geografischem Bezug ohne großen Aufwand zu erstellen. Den Abschluss bildet ein Beispielszenario, dass unter Verwendung einiger der Regeln mehrere Graphen mit geografischem Bezug generiert. Anschließend werden diese zu einem Gesamtgraphen zusammengefasst um das gesamte Szenario darzustellen.

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Bieber, Gerald; Kirste, Thomas [Referent]; Urban, Bodo [Betreuer]; Stricker, Didier [Referent]

Methodik zur mobilen Erfassung körperlicher Aktivität mittels Beschleunigungssensoren

2014

Rostock, Univ., Diss., 2014

Ein ausgewogenes Verhältnis zwischen körperlicher Aktivität und gesunder Ernährung trägt zu einem gesunden Lebensstil bei. Oftmals wird jedoch ein optimales Maß an Bewegung und Ernährung nicht erreicht, so dass Übergewicht und gesundheitliche Probleme auftreten können. Eine objektive Erhebung der Bewegungssituation kann hierbei Defizite erkennen und eine Intervention unterstützen. Für die Erfassung der körperlichen Aktivität mittels Beschleunigungssensoren war es bislang üblich, entweder nur einfachste körperliche Aktivitäten zu erfassen oder spezielle Sensoren einzusetzen, die exakt am Körper auszurichten sind. Die sinnvolle Nutzung von nur einem Sensor zur Aktivitätserfassung, der beliebig orientiert getragen wird, war bisher nicht möglich, da die erhobenen Sensordaten bei Verdrehung nur eine eingeschränkte Erkennung der ausgeführten Aktivitäten zulassen. Die vorliegende Arbeit beschreibt die Methodik zur mobilen Erfassung körperlicher Aktivität mittels Beschleunigungssensoren. Hierbei wird ein neues Verfahren eingesetzt, welches die Orientierung des Sensorsystems identifiziert und die gemessenen Beschleunigungsdaten in ein neues, geeignetes Bezugssystem transformiert. Zur Bestimmung der Ausrichtung des Messsystems werden spezifische Bewegungsinformationen einer Aktivität genutzt, die eine vollständige Bestimmung der Orientierung erlauben. Durch die Transformation der Sensordaten in ein neues Bezugssystem wird es möglich, die Menge der Trainingsdaten zu reduzieren und die Erkennungsrate zu erhöhen. Die hierfür notwendigen Teilkomponenten werden als Module definiert und in einer Gesamtarchitektur zusammengefasst. Dieses Gesamtmodell basiert auf der Aktivitätserkennung mittels merkmalsbasierter Mustererkennung. In Teilmodulen werden die Messdatenvorverarbeitungen zur Signalschätzung, die Merkmalsextraktion sowie die Klassifizierung abgebildet. Das Gesamtkonzept beinhaltet die Auswahl der relevanten Merkmale sowie eines geeigneten Klassifizierers für mobile Endgeräte. Als Nachweis der Umsetzbarkeit wurde eine Implementierung auf einem handelsüblichen Mobiltelefon durchgeführt. Die Evaluation zeigt, dass die Bestimmung beliebiger Sensororientierungen und die Generierung des Bezugssystems dynamisch möglich sind und eine praxistaugliche Aktivitätserkennung umsetzbar ist. Der Technologiedemonstrator Dia- Trace liefert den Nachweis, dass auf dieser Grundlage ein mobiles Assistenzsystem sinnvoll zur Behandlung von Adipositaspatienten eingesetzt werden kann.

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Stenin, Igor; Hansen, Stefan; Becker, Meike; Sakas, Georgios; Fellner, Dieter W.; Klenzner, Thomas; Schipper, Jörg

Minimally Invasive Multiport Surgery of the Lateral Skull Base

2014

BioMed Research International

Objective: Minimally invasive procedures minimize iatrogenic tissue damage and lead to a lower complication rate and high patient satisfaction. To date only experimental minimally invasive single-port approaches to the lateral skull base have been attempted. The aim of this study was to verify the feasibility of a minimally invasive multiport approach for advanced manipulation capability and visual control and develop a software tool for preoperative planning. Methods: Anatomical 3D models were extracted from twenty regular temporal bone CT scans. Collision-free trajectories, targeting the internal auditory canal, round window, and petrous apex, were simulated with a specially designed planning software tool. A set of three collision-free trajectories was selected by skull base surgeons concerning the maximization of the distance to critical structures and the angles between the trajectories. Results: A set of three collision-free trajectories could be successfully simulated to the three targets in each temporal bone model without violating critical anatomical structures. Conclusion: A minimally invasive multiport approach to the lateral skull base is feasible. The developed software is the first step for preoperative planning. Further studies will focus on cadaveric and clinical translation.

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Aehnelt, Mario; Bader, Sebastian

Mobile Informationsassistenz für die Montage

2014

Technische Unterstützungssysteme, die die Menschen wirklich wollen

Transdisziplinäre Konferenz zum Thema Technische Unterstützungssysteme <1, 2014, Hamburg, Germany>

Montagearbeiter zeichnen sich gegenüber automatisierten Montagesystemen nicht nur durch ihre Flexibilität sondern auch durch kreative Lösungsstrategien aus. Diese beruhen auf Erfahrungswissen und einer großen kognitiven Leistungsfähigkeit. Sie erfordern jedoch auch eine situativ angepasste Informationsassistenz. Der Beitrag beschreibt ein intelligentes System zur Informationsunterstützung des Montagearbeiters im Bereich der Kleinserien- und Einzelfertigung. Aufbauend auf vorangegangenen Arbeiten wird ein Framework aus intelligenten Komponenten, z.B. wahrscheinlichkeitsbasierten Verhaltensmodellen, kognitiven Architekturen sowie mobilen Assistenzlösungen, vorgestellt. Dieses unterstützt den Montagearbeiter in Abhängigkeit seiner Arbeitsaufgaben durch eine bedarfsgerechte Bereitstellung von Arbeitsanweisungen und es überwacht die korrekte Durchführung der Montagearbeiten.

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Nesterenko, Dmitrijs; Aehnelt, Mario [Betreuer]; Urban, Bodo [Betreuer]

Mobile und situative Informationsverteilung auf verteilten Displays

2014

Rostock, Univ., Bachelor Thesis, 2014

Bei der Montage von Maschinen und Anlagen werden Informationen über Aufträge, konstruktive oder verfahrenstechnische Details sowie zu verarbeitende Bauteile und Materialien benötigt. Zur Sicherstellung ihrer Aktualität sind digitale Technologien für die Bereitstellung und Darstellung der Informationen am stationären, teil-stationären und mobilen Arbeitsplatz erforderlich. Umgebungen, die mit den Technologien ausgestattet sind, sollen die Information so verteilen, dass die Erfassung und Verarbeitung der Informationen durch den Montagearbeiter den Montageprozess nicht zusätzlich behindert sondern unterstützt. Je nach Ausstattung und Arbeitssituation ist die Informationsverteilung unterschiedlich. Im Rahmen dieser Bachelorarbeit soll ein Konzept entwickelt werden, der die situative Verteilung der Informationen auf die verteilten Displays ermöglicht. Außerdem soll ein Prototyp für das Konzept entwickelt werden und in eine bestehende Anwendung integriert werden. Die zu implementierende Funktionalitäten für den Prototyp werden im Laufe der Arbeit eingeschränkt.

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Hammon, Matthias; Cavallaro, Alexander; Erdt, Marius; Dankerl, Peter; Kirschner, Matthias; Drechsler, Klaus; Wesarg, Stefan; Uder, Michael; Janka, Rolf

Model-Based Pancreas Segmentation in Portal Venous Phase Contrast-Enhanced CT Images

2014

Journal of Digital Imaging

This study aims to automatically detect and segment the pancreas in portal venous phase contrast-enhanced computed tomography (CT) images. The institutional review board of the University of Erlangen-Nuremberg approved this study and waived the need for informed consent. Discriminative learning is used to build a pancreas tissue classifier incorporating spatial relationships between the pancreas and surrounding organs and vessels. Furthermore, discrete cosine and wavelet transforms are used to build texture features to describe local tissue appearance. Classification is used to guide a constrained statistical shape model to fit the data. The algorithm to detect and segment the pancreas was evaluated on 40 consecutive CT data that were acquired in the portal venous contrast agent phase. Manual segmentation of the pancreas was carried out by experienced radiologists and served as reference standard. Threefold cross validation was performed. The algorithm-based detection and segmentation yielded an average surface distance of 1.7 mm and an average overlap of 61.2 % compared with the reference standard. The overall runtime of the system was 20.4 min. The presented novel approach enables automatic pancreas segmentation in portal venous phase contrast-enhanced CT images which are included in almost every clinical routine abdominal CT examination. Reliable pancreatic segmentation is crucial for computer-aided detection systems and an organ-specific decision support.

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De Stefano, Antonio; Santos, Pedro [Betreuer]; Tausch, Reimar [Betreuer]

Modeling a Virtual Robotic System for Cultural Heritage Digitization

2014

Neapel, Univ., Master Thesis, 2014

The objective of this thesis is the development of an inverse kinematic solver application which allows a camera mounted onto the robotic arm to resolve occlusion in a 3D model, by reaching a position and a camera direction, given in this case by a path creator, while in the reality the pose is given from a view planning; The results will be visualized and simulated in a virtual environment which represents the CultArm3D subsystem of the CultLAb3D. This thesis is part of the Cultural Heritage Project of the Fraunhofer Institute for Visual Computing, which is concerned with the development of inexpensive automated 3D-digitization of objects of cultural value. Given that many museums lack exhibition space for their numerous exhibits and that these museums are scattered around the world, the Cultural Heritage Project seeks to provide worldwide virtual access to these exhibits.

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Schinko, Christoph; Ullrich, Torsten; Fellner, Dieter W.

Modeling with High-level Descriptions and Low-level Details

2014

Proceedings of the International Conferences on Interfaces and Human Computer Interaction 2014, Game and Entertainment Technologies 2014 and Computer Graphics, Visualization, Computer Vision and Image Processing 2014

IADIS International Conference Computer Graphics, Visualization, Computer Vision and Image Processing (CGVCVIP) <8, 2014, Lisbon, Portugal>

Procedural modeling techniques can be used to encode a geometric shape on a high and abstract level: each class of objects and shapes is represented by one algorithm; and each artifact is one set of high-level parameters. In this paper, we use a generative object description and register it to real-world data e.g. laser scans. Afterwards, we can use the fitted procedural model to modify existing 3D shapes. The high-level description can be used to resemble real-world objects or create new ones. In this way, we can design shapes using both low-level details and high-level shape parameters at the same time.

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Djakow, Maxim; Braun, Andreas; Marinc, Alexander

MoviBed - Sleep Analysis Using Capacitive Sensors

2014

Universal Access in Human-Computer Interaction: Part IV

International Conference on Universal Access in Human-Computer Interaction (UAHCI) <8, 2014, Heraklion, Crete, Greece>

Sleep disorders are a wide-spread phenomenon that can gravely affect personal health and well-being. An individual sleep analysis is a first step in identifying unusual sleeping patterns and providing suitable means for further therapy and preventing escalation of symptoms. Typically such an analysis is an intrusive method and requires the user to stay in a sleep laboratory. In this work we present a method for detecting sleep patterns based on invisibly installed capacitive proximity sensors integrated into the bed frame. These sensors work with weak electric fields and do not disturb sleep. Using the movements of the sleeping person we are able to provide a continuous analysis of different sleep phases. The method was tested in a prototypical setup over multiple nights.

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Damer, Naser; Opel, Alexander

Multi-biometric Score-Level Fusion and the Integration of the Neighbors Distance Ratio

2014

Image Analysis and Recognition. Proceedings Part II

International Conference on Image Analysis and Recognition (ICIAR) <11, 2014, Vilamoura, Portugal>

Multi-biometrics aims at building more accurate unified biometric decisions based on the information provided by multiple biometric sources. Information fusion is used to optimize the process of creating this unified decision. In previous works dealing with score-level multibiometric fusion, the scores of different biometric sources belonging to the comparison of interest are used to create the fused score. The novelty of this work focuses on integrating the relation of the fused scores to other comparisons within a 1:N comparison. This is performed by considering the neighbors distance ratio in the ranked comparisons set within a classification-based fusion approach. The evaluation was performed on the Biometric Scores Set BSSR1 database and the enhanced performance induced by the integration of neighbors distance ratio was clearly presented.

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Multi-Sensory Environment Analysis and Human Activity Recognition via Wearable Technologies

2014

WOAR 2014

Workshop on Sensor-Based Activity Recognition (WOAR) <1, 2014, Rostock, Germany>

The sensing of human activities and user surrounding environments is an essential topic in computer science. Application domains include the Ambient Assisted Living (AAL), healthcare, sports gear and military use cases. Especially mobile or wearable technologies made significant progress in the past years. The current development of Smartwatches and Smartphones which include a variety of sensors is a good example for this progress. With the increasing sensor density in unobtrusive wearable designs, new ways for complex Human Activity Recognition (HAR) and environmental sensing (ES) are opened. This paper focuses on the current state of the art in wearable sensor technologies and gives a short overview of present techniques for HAR and ES. Therefore, a classification of sensors by use case and body position is made. Furthermore, the principal challenges and issues are discussed and known solutions will be referenced. Finally, existing problems that should be addressed are pointed out.

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Ackermann, Jens; Langguth, Fabian; Fuhrmann, Simon; Kuijper, Arjan; Goesele, Michael

Multi-View Photometric Stereo by Example

2014

3DV 2014 - Volume I

International Conference on 3D Vision (3DV) <2, 2014, Tokyo, Japan>

We present a novel multi-view photometric stereo technique that recovers the surface of textureless objects with unknown BRDF and lighting. The camera and light positions are allowed to vary freely and change in each image. We exploit orientation consistency between the target and an example object to develop a consistency measure. Motivated by the fact that normals can be recovered more reliably than depth, we represent our surface as both a depth map and a normal map. These maps are jointly optimized and allow us to formulate constraints on depth that take surface orientation into account. Our technique does not require the visual hull or stereo reconstructions for bootstrapping and solely exploits image intensities without the need for radiometric camera calibration. We present results on real objects with varying degree of specularity and show that these can be used to create globally consistent models from multiple views.

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Brunton, Alan; Bolkart, Timo; Wuhrer, Stefanie

Multilinear Wavelets: A Statistical Shape Space for Human Faces

2014

Computer Vision - ECCV 2014. Proceedings Part I

European Conference on Computer Vision (ECCV) <13, 2014, Zurich, Switzerland>

We present a statistical model for 3D human faces in varying expression, which decomposes the surface of the face using a wavelet transform, and learns many localized, decorrelated multilinear models on the resulting coefficients. Using this model we are able to reconstruct faces from noisy and occluded 3D face scans, and facial motion sequences. Accurate reconstruction of face shape is important for applications such as tele-presence and gaming. The localized and multi-scale nature of our model allows for recovery of fine-scale detail while retaining robustness to severe noise and occlusion, and is computationally efficient and scalable. We validate these properties experimentally on challenging data in the form of static scans and motion sequences. We show that in comparison to a global multilinear model, our model better preserves fine detail and is computationally faster, while in comparison to a localized PCA model, our model better handles variation in expression, is faster, and allows us to fix identity parameters for a given subject.

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Aginako, Naiara; Irujo Arraiza, Juan; Cuadros, Montse; Raffaelli, Matteo; Kähm, Olga; Damer, Naser; Neto, Joao P. Neto

Multimedia Analysis of Video Sources

2014

SIGMAP 2014. Proceedings of the 11th International Conference on Signal Processing and Multimedia Applications

International Conference on Signal Processing and Multimedia Applications (SIGMAP) <11, 2014, Vienna, Austria>

Law Enforcement Agencies (LEAs) spend increasing efforts and resources on monitoring open sources, searching for suspicious behaviours and crime clues. The task of efficiently and effectively monitoring open sources is strongly linked to the capability of automatically retrieving and analyzing multimedia data. This paper presents a multimodal analytics system, created in cooperation with European LEAs. In particular it is described how the video analytics subsystem produces a workflow of multimedia data analysis processes. After a first analysis of video files, images are extracted in order to perform image comparison, classification and face recognition. In addition, audio content is extracted to perform speaker recognition and multilingual analysis of text transcripts. The integration of multimedia analysis results allows LEAs to extract pertinent knowledge from the gathered information.

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Trimpop, John; Urban, Bodo [Betreuer]; Bieber, Gerald [Betreuer]

Multisensorische Aktivitätserkennung an Arm und Kopf

2014

Rostock, Univ., Master Thesis, 2014

Innovative Smart Devices ermöglichen eine umfassende, permanente und unaufdringliche Erkennung körperlicher Aktivität. Neben Smartphones und Smartwatches existieren auf dem Markt mittlerweile auch Smartglasses verschiedener Hersteller. Da die Human Activity Recognition mit nahe der Hüfte und am Arm getragener Sensoren bereits gut funktioniert, wird im Rahmen dieser Mastarbeit untersucht, ob eine auf Kopfsensorik basierende Aktivitätserkennung alleinstehend beziehungsweise in ein multisensorisches Netzwerk eingebettet durchführbar ist. Für dieses Vorhaben werden Konzepte zur multisensorischen Aktivitätserkennung und Sensorfusion entwickelt, die in einem umfangreichen System, bestehend aus mehreren Komponenten, implementiert werden. Das System kennzeichnet sich als Aktivitätstagebuch, welches Daten von am Kopf, am Arm und in der Hosentasche getragener Sensoren verarbeitet, auswertet und speichert. Die Ergebnisse einer ausgiebigen Evaluation unter Nutzung des Systems zeigen auf, dass am Kopf befestigte Sensoren für die Aktivitätserkennung eingesetzt werden können. Durch die Integration der Kopfposition innerhalb eines multisensorischen Netzwerkes konnten die Ergebnisse kontinuierlich verbessert werden. Zusätzliche Untersuchungen präsentieren darüber hinaus, dass verschiedene Geräte und Positionen am Kopf für die Aktivitätserkennung in Frage kommen und, dass die Kopfbewegung im Hinblick auf die körperliche Aktivität sehr charakteristisch ist.

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Mutual Information-Based Piecewise Planar Object Tracking

2014

Darmstadt, TU, Master Thesis, 2014

This master thesis deals with a template based tracking algorithm for piecewise planar objects. It is robust against changes in the appearance of the object (occlusion, illumination variation, specularities). The version that we propose supports multiple cameras. The method consists in minimizing the error between the observed images of the object and the warped images of the planes. We use for that an estimation of the pose of the object, which is to say a rigid 3D transformation. The robustness is obtained by using the mutual information as registration function. The main drawback of the mutual information is that it has a high computation complexity. We use an inverse composition approach for the warp update, so that pre-computations can be done and it decreases the complexity of the algorithm. We develop a way of computing the warp update and analyse the impact of this initiative on the optimization process. We also determine the optimal parameters for running the algorithms.

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Kochtchi, Arjtom; Landesberger, Tatiana von; Biemann, Chris

Networks of Names: Visual Exploration and Semi-Automatic Tagging of Social Networks from Newspaper Articles

2014

Computer Graphics Forum

International EuroVis Workshop on Visual Analytics (EuroVA) <5, 2014, Swansea, Wales, UK>

Understanding relationships between people and organizations by reading newspaper articles is difficult to manage for humans due to the large amount of data. To address this problem, we present and evaluate a new visual analytics system, which offers interactive exploration and tagging of social networks extracted from newspapers. For the visual exploration of the network, we extract "interesting" neighbourhoods of nodes, using a new degree of interest (DOI) measure based on edges instead of nodes. It improves the seminal definition of DOI, which we find to produce the same "globally interesting" neighbourhoods in our use case, regardless of the query. Our approach allows answering different user queries appropriately, avoiding uniform search results. We propose a user-driven pattern-based classifier for discovery and tagging of non-taxonomic semantic relations. Our approach does not require any a-priori user knowledge, such as expertise in syntax or pattern creation. An evaluation shows that our classifier is capable of identifying known lexico-syntactic patterns as well as various domain-specific patters. Our classifier yields good results already with a small amount of training, and continuously improves through user feedback. We conduct a user study to evaluate whether our visual interactive system has an impact on how users tag relationships, as compared to traditional text-based interfaces. Study results suggest that users of the visual system tend to tag more concisely, avoiding too abstract or overly specific relationship labels.

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Perey, Christine; Manson, Rob; Preda, Marius; Trevett, Neil; Lechner, Martin; Percivall, George; Engelke, Timo; Lefkin, Peter; Mahone, Bruce; Nielsen, Mary Lynne

Open and Interoperable Augmented Reality

2014

IEEE International Symposium on Mixed and Augmented Reality - Science & Technology 2014

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <13, 2014, Munich, Germany>

This tutorial provides comprehensive and in depth information that content publishers and developers need to know when planning to develop and deploy content for AR and designing the AR experiences in a manner that supports maximum reach and data portability. The tutorial presenters are experts in the area of individual standards and open source projects. They will describe open protocols and APIs that can be integrated with existing proprietary technology silos or used as alternatives to reduce delays and cost over the lifetime of AR-assisted system development and ownership.

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Becker, Meike; Hansen, Stefan; Wesarg, Stefan; Sakas, Georgios

Path Planning for Multi-port Lateral Skull Base Surgery Based on First Clinical Experiences

2014

Clinical Image-Based Procedures. Translational Research in Medical Imaging

International Workshop on Clinical Image-based Procedures (CLIP) <2, 2013, Nagoya, Japan>

Our research project investigates a multi-port minimally-traumatic approach for lateral skull base surgery, where the surgical target shall be reached through up to three drill canals. For this purpose, an accurate path planning is crucial. In the present work, we propose a semiautomatic path planning approach for multi-port minimally-traumatic lateral skull base surgery. The best path combinations are automatically determined by optimizing the angles and distance buffers of the drill canals. We compare the automatically computed path combinations for 20 data sets to those selected manually by two different clinicians. The experiments prove that we can adequately reproduce the clinicians' choice.

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Becker, Meike; Sakas, Georgios [Referent]; Fellner, Dieter W. [Betreuer]; Schipper, Jörg [Referent]

Patientenspezifische Planung für die Multi-Port Otobasischirurgie

2014

Darmstadt, TU, Diss., 2014

Bisher werden Operationen im Bereich der seitlichen Schädelbasis (Otobasis) stark invasiv durchgeführt. Um die Traumatisierung für den Patienten zu reduzieren, wird seit kurzem ein Multi-Port Ansatz untersucht, bei dem bis zu drei dünne Bohrkanäle von der Schädeloberfläche bis zum Operationsziel angelegt werden. Aufgrund der Minimalinvasivität des neuen Eingriffs ist die visuelle Kontrolle durch den Chirurgen nicht mehr möglich. Somit ist eine präzise patientenspezifische Planung basierend auf Bilddaten zwingend erforderlich. Der Fokus dieser Arbeit liegt daher auf der Planung eines Multi-Port Eingriffs basierend auf patientenspezifischen Modellen. Zur Generierung dieser Modelle habe ich zunächst Methoden für die Segmentierung der Risikostrukturen der Otobasis in Computertomographiedaten entwickelt. Die Herausforderungen dabei sind die geringe Größe der Strukturen, der fehlende Kontrast zum umliegenden Gewebe sowie die zum Teil variierende Form und Bildintensität. Daher schlage ich die Verwendung eines modellbasierten Ansatzes - das Probabilistic Active Shape Model - vor. Dieses habe ich für die Risikostrukturen der Otobasis adaptiert und intensiv evaluiert. Dabei habe ich gezeigt, dass die Segmentierungsgenauigkeit im Bereich der manuellen Segmentierungsgenauigkeit liegt. Ferner habe ich Methoden für die automatische Planung der Bohrkanäle basierend auf den durch die Segmentierung gewonnenen patientenspezifischen Modellen entwickelt. Die Herausforderung hierbei ist, dass der Multi-Port Eingriff noch nicht im klinischen Einsatz ist und somit Erfahrung mit der neuen Strategie fehlt. Daher wurde zunächst ein Planungstool zur Berechnung einer Menge von zulässigen Bohrkanälen entwickelt und die manuelle Auswahl einer Bohrkanalkombination ermöglicht. Damit haben zwei Ärzte eine erste Machbarkeitsanalyse durchgeführt. Die so gewonnene Erfahrung und Datenbasis habe ich formalisiert und ein Modell für die automatische Planung einer Bohrkanalkombination abgeleitet. Die Evaluation zeigt, dass auf diese Weise Bohrkanalkombinationen vergleichbar mit der manuellen Wahl der Ärzte berechnet werden können. Damit ist erstmals die computergestützte Planung eines Multi-Port Eingriffs an der Otobasis möglich.

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Steger, Sebastian; Jung, Florian; Wesarg, Stefan

Personalized Articulated Atlas with a Dynamic Adaptation Strategy for Bone Segmentation in CT- or CT/MR Head & Neck Images

2014

Medical Imaging 2014: Image Processing

SPIE Medical Imaging Symposium <2014, San Diego, CA, USA>

This paper presents a novel segmentation method for the joint segmentation of individual bones in CT- or CT/MR- head & neck images. It is based on an articulated atlas for CT images that learned the shape and appearance of the individual bones along with the articulation between them from annotated training instances. First, a novel dynamic adaptation strategy for the atlas is presented in order to increase the rate of successful adaptations. Then, if a corresponding CT image is available the atlas can be enriched with personalized information about shape, appearance and size of the individual bones from that image. Using mutual information, this personalized atlas is adapted to an MR image in order to propagate segmentations. For evaluation, a head & neck bone atlas created from 15 manually annotated training images was adapted to 58 clinically acquired head & neck CT datasets. Visual inspection showed that the automatic dynamic adaptation strategy was successful for all bones in 86% of the cases. This is a 22% improvement compared to the traditional gradient descent based approach. In leave-one-out cross validation manner the average surface distance of the correctly adapted items was found to be 0.68 mm. In 20 cases corresponding CT/MR image pairs were available and the atlas could be personalized and adapted to the MR image. This was successful in 19 cases.

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Ackermann, Jens; Goesele, Michael [Referent]; Klein, Reinhard [Betreuer]

Photometric Reconstruction from Images: New Scenarios and Approaches for Uncontrolled Input Data

2014

Darmstadt, TU, Diss., 2014

The changes in surface shading caused by varying illumination constitute an important cue to discern fine details and recognize the shape of texture less objects. Humans perform this task subconsciously, but it is challenging for a computer because several variables are unknown and intermix in the light distribution that actually reaches the eye or camera. In this work, we study algorithms and techniques to automatically recover the surface orientation and reflectance properties from multiple images of a scene. Photometric reconstruction techniques have been investigated for decades but are still restricted to industrial applications and research laboratories. Making these techniques work on more general, uncontrolled input without specialized capture setups has to be the next step but is not yet solved. We explore the current limits of photometric shape recovery in terms of input data and propose ways to overcome some of its restrictions. Many approaches, especially for non-Lambertian surfaces, rely on the illumination and the radiometric response function of the camera to be known. The accuracy such algorithms are able to achieve depends a lot on the quality of an a priori calibration of these parameters. We propose two techniques to estimate the position of a point light source, experimentally compare their performance with the commonly employed method, and draw conclusions which one to use in practice. We also discuss how well an absolute radiometric calibration can be performed on uncontrolled consumer images and show the application of a simple radiometric model to re-create night-time impressions from color images. A focus of this thesis is on Internet images which are an increasingly important source of data for computer vision and graphics applications. Concerning reconstructions in this setting we present novel approaches that are able to recover surface orientation from Internet webcam images. We explore two different strategies to overcome the challenges posed by this kind of input data. One technique exploits orientation consistency and matches appearance profiles on the target with a partial reconstruction of the scene. This avoids an explicit light calibration and works for any reflectance that is observed on the partial reference geometry. The other technique employs an outdoor lighting model and reflectance properties represented as parametric basis materials. It yields a richer scene representation consisting of shape and reflectance. This is very useful for the simulation of new impressions or editing operations, e.g. relighting. The proposed approach is the first that achieves such a reconstruction on webcam data. Both presentations are accompanied by evaluations on synthetic and real-world data showing qualitative and quantitative results. We also present a reconstruction approach for more controlled data in terms of the target scene. It relies on a reference object to relax a constraint common to many photometric stereo approaches: the fixed camera assumption. The proposed technique allows the camera and light source to vary freely in each image. It again avoids a light calibration step and can be applied to non-Lambertian surfaces. In summary, this thesis contributes to the calibration and to the reconstruction aspects of photometric techniques. We overcome challenges in both controlled and uncontrolled settings, with a focus on the latter. All proposed approaches are shown to operate also on non-Lambertian objects.

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Policy Modeling Methodologies

2014

Handbook of Research on Advanced ICT Integration for Governance and Policy Modeling

The process to develop sustainable public policies is precisely defined in public authorities to ensure the involvement of all stakeholders and to ensure the creation of an effective policy. The inclusion of ICT in most of the today's applied policy making processes in public authorities is mostly less considered. Indeed, other process definitions with focus on ICT inclusion in policy modeling still exist, but they are mostly not well defined. This chapter gives an overview about the existing policy modeling process types and explains their major focus and how they consider ICT and the practical process in public authorities. Afterwards based on these descriptions the general requirements on a new ICT-oriented policy modeling process that allows the inclusion of ICT into a valid and useful process for public authorities will be given.

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Bender, Jan; Koschier, Dan; Charrier, Patrick; Weber, Daniel

Position-based Simulation of Continuous Materials

2014

Computers & Graphics

We introduce a novel fast and robust simulation method for deformable solids that supports complex physical effects like lateral contraction, anisotropy or elastoplasticity. Our method uses a continuum-based formulation to compute strain and bending energies for two- and three-dimensional bodies. In contrast to previous work, we do not determine forces to reduce these potential energies, instead we use a position-based approach. This combination of a continuum-based formulation with a position-based method enables us to keep the simulation algorithm stable, fast and controllable while providing the ability to simulate complex physical phenomena lacking in former position-based approaches. We demonstrate how to simulate cloth and volumetric bodies with lateral contraction, bending, plasticity as well as anisotropy and proof robustness even in case of degenerate or inverted elements. Due to the continuous material model of our method further physical phenomena like fracture or viscoelasticity can be easily implemented using already existing approaches. Furthermore, a combination with other geometrically motivated methods is possible.

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Kahn, Svenja; Fellner, Dieter W. [Betreuer]; Stricker, Didier [Referent]

Precise Depth Image Based Real-Time 3D Difference Detection

2014

Darmstadt, TU, Diss., 2014

3D difference detection is the task to verify whether the 3D geometry of a real object exactly corresponds to a 3D model of this object. Detecting differences between a real object and a 3D model of this object is for example required for industrial tasks such as prototyping, manufacturing and assembly control. State of the art approaches for 3D difference detection have the drawback that the difference detection is restricted to a single viewpoint from a static 3D position and that the differences cannot be detected in real time. This thesis introduces real-time 3D difference detection with a hand-held depth camera. In contrast to previous works, with the proposed approach, geometric differences can be detected in real time and from arbitrary viewpoints. Therefore, the scan position of the 3D difference detection be changed on the fly, during the 3D scan. Thus, the user can move the scan position closer to the object to inspect details or to bypass occlusions. The main research questions addressed by this thesis are: Q1 How can 3D differences be detected in real time and from arbitrary viewpoints using a single depth camera? Q2 Extending the first question, how can 3D differences be detected with a high precision? Q3 Which accuracy can be achieved with concrete setups of the proposed concept for real time, depth image based 3D difference detection? This thesis answers Q1 by introducing a real-time approach for depth image based 3D difference detection. The real-time difference detection is based on an algorithm which maps the 3D measurements of a depth camera onto an arbitrary 3D model in real time by fusing computer vision (depth imaging and pose estimation) with a computer graphics based analysis-by-synthesis approach. Then, this thesis answers Q2 by providing solutions for enhancing the 3D difference detection accuracy, both by precise pose estimation and by reducing depth measurement noise. A precise variant of the 3D difference detection concept is proposed, which combines two main aspects. First, the precision of the depth camera's pose estimation is improved by coupling the depth camera with a very precise coordinate measuring machine. Second, measurement noise of the captured depth images is reduced and missing depth information is filled in by extending the 3D difference detection with 3D reconstruction. The accuracy of the proposed 3D difference detection is quantified by a ground-truth based, quantitative evaluation. This provides an answer to Q3. The accuracy is evaluated both for the basic setup and for the variants that focus on a high precision. The quantitative evaluation using real-world data covers both the accuracy which can be achieved with a time-of-flight camera (SwissRanger 4000) and with a structured light depth camera (Kinect). With the basic setup and the structured light depth camera, differences of 8 to 24 millimeters can be detected from one meter measurement distance. With the enhancements proposed for precise 3D difference detection, differences of 4 to 12 millimeters can be detected from one meter measurement distance using the same depth camera. By solving the challenges described by the three research question, this thesis provides a solution for precise real-time 3D difference detection based on depth images. With the approach proposed in this thesis, dense 3D differences can be detected in real time and from arbitrary viewpoints using a single depth camera. Furthermore, by coupling the depth camera with a coordinate measuring machine and by integrating 3D reconstruction in the 3D difference detection, 3D differences can be detected in real time and with a high precision.

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Caldera, Christian; Berndt, René; Eggeling, Eva; Schröttner, Martin; Fellner, Dieter W.

PRIMA - Towards an Automatic Review/Paper Matching Score Calculation

2014

CONTENT 2014

International Conference on Creative Content Technologies (CONTENT) <6, 2014, Venice, Italy>

Programme chairs of scientific conferences face a tremendous time pressure. One of the most time-consuming steps during the conference workflow is assigning members of the international programme committee (IPC) to the received submissions. Finding the best-suited persons for reviewing strongly depends on how the paper matches the expertise of each IPC member. While various approaches like "bidding" or "topic matching" exist in order to make the knowledge of these expertises explicit, these approaches allocate a considerable amount of resources on the IPC member side. This paper introduces the Paper Rating and IPC Matching Tool (PRIMA), which reduces the workload for both - IPC members and chairs - to support and improve the assignment process.

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Baar, Teun; Samadzadegan, Sepideh; Brettel, Hans; Urban, Philipp; Segovia, Maria V. Ortiz

Printing Gloss Effects in a 2.5D System

2014

Measuring, Modeling, and Reproducing Material Appearance

Measuring, Modeling, and Reproducing Material Appearance (MMRMA) <1, 2014, San Francisco, CA, USA>

An important aspect for print quality assessment is the perceived gloss level across the printout. There exists a strong relationship between the surface roughness of a printout and the amount of specular reflection which is perceived as gloss variations. Different print parameters influence the surface roughness of the printouts such as the paper substrate, the type of inks and the print method. The lack of control over the print's surface roughness may result in artifacts such as bronzing and differential gloss. Employing a 2.5D or relief printing system, we are able to control the printout roughness by manipulating the way the ink is deposited in a layer-by-layer basis. By changing the deposition time in between two layers of white ink and the order on which the pixels are printed, we achieve different gloss levels from a matte to a glossy appearance that can be controlled locally. Understanding the relationship between different printing parameters and the resulting gloss level allows us: to solve differential gloss artifacts (to obtain a print with a full gloss or matte finish) and to use the local gloss variations to create reflection effects in the printouts. Applications related to security printing have also been explored. Our results showed a reduced level of gloss toward a matte appearance as the ink deposition time between the layers was increased, allowing more time for the ink to dry between passes. We measured the gloss levels using a gloss meter and a psychophysical experiment was conducted to validate our measurements and observations.

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Butt, Moazzam; Damer, Naser; Rathgeb, Christian

Privacy Preserved Duplicate Check using Multi-biometric Fusion

2014

FUSION 2014

International Conference on Information Fusion (FUSION) <17, 2014, Salamanca, Spain>

Automated recognition of individuals can be performed using biometrics without any requirement of explicit knowledge of a PIN or a password. On the one side biometrics has given convenience to citizens as they do not need to memorize a bunch of passwords, but on the other side intra (inter) class variations within (between) biometric features makes biometric authentications untrustworthy. Therefore, decisions based on biometric authentications are made more reliable by using several biometric authentications performed on single or multiple biometric modalities (i.e. multi-biometric fusion). This paper describes a method to identify if a person tries to re-enrol him/herself in a database, when he/she is already enrolled. This is referred to as duplicate check. In this work, duplicate check is performed using two modalities: face and iris. The templates used during the duplicate check are compliant to the ISO/IEC 24745 - Biometric information protection. Such templates are known as protected biometric templates. The protected biometric templates used in this work are generated using the recently published irreversible transformation based on Bloom filters. Scores are calculated from face and iris Bloom filters based templates by comparison with their respective enrolment templates using the normalized Hamming distance. As a decision of the duplicate check, these scores from both modalities are fused with appropriate weighting factors in order to get improved performance compared to using single individual modalities. The presented scheme is experimentally validated using two public benchmark databases namely the LFW and the CASIA-Iris-Thousand databases for face and iris respectively.

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Privacy Protection of Biometric Templates

2014

HCI International 2014 - Posters' Extended Abstracts. Proceedings Part I

International Conference on Human-Computer Interaction (HCII) <16, 2014, Heraklion, Crete, Greece>

Although many biometric characteristics are not secrets, biometric reference data (also known as biometric templates) need to be stored securely and to be protected against unauthorized use. For this purpose, biometric template protection techniques have been developed that do not only prevent privacy leakage and provide confidentiality of the stored biometric templates, but address also problems like identity theft and cross-matching of biometric templates stored in different systems. This paper describes the security and privacy risks associated with storing biometric data and highlights the necessity of using biometric template protection as a potential remedy to these risks. Privacy considerations are discussed with respect to using fingerprint verification for access control to a public outdoor swimming pool.

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Zmugg, René; Thaller, Wolfgang; Krispel, Ulrich; Edelsbrunner, Johannes; Havemann, Sven; Fellner, Dieter W.

Procedural Architecture Using Deformation-aware Split Grammars

2014

The Visual Computer

With the current state of video games growing in scale, manual content creation may no longer be feasible in the future. Split grammars are a promising technology for large-scale procedural generation of urban structures, which are very common in video games. Buildings with curved parts, however, can currently only be approximated by static pre-modelled assets, and rules apply only to planar surface parts. We present an extension to split grammar systems that allow the creation of curved architecture through integration of free-form deformations at any level in a grammar. Further split rules can then proceed in two different ways. They can either adapt to these deformations so that repetitions can adjust to more or less space, while maintaining length constraints, or they can split the deformed geometry with straight planes to introduce straight structures on deformed geometry.

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Havemann, Sven; Wagener, Olaf; Fellner, Dieter W.

Procedural Shape Modeling in Digital Humanities: Potentials and Issues

2014

3D Research Challenges in Cultural Heritage

Procedural modeling is a technology that has great potential to make the abundant variety of shapes that have to be dealt with in Digital Humanities accessible and understandable. There is a gap, however, between technology on the one hand and the needs and requirements of the users in the Humanities community. In this paper we analyze the reasons for the limited uptake of procedural modeling and sketch possible ways to circumvent the problem. The key insight is that we have to find matching concepts in both fields, which are on the one hand grounded in the way shape is explained, e.g., in art history, but which can also be formalized to make them accessible to digital computers.

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Siegmund, Dirk; Busch, Christoph [Betreuer]; Damer, Naser [Betreuer]

Prototypical Development of an In-Shop Advertisment System using Body Dimension Recognition

2014

Darmstadt, Hochschule, Master Thesis, 2014

This thesis outlines a system created to give consumers in the fashion industry an idea of how an item of clothing will look on them before trying it on. In the form of a short video, items of clothing are projected virtually onto an image of the user. Through the use of this system, retailers and manufacturers have the chance to immediately display their clothes on potential customers.

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Bieber, Gerald; Papenfuß, Frank; Vahl, Matthias; Woitzel, Egmont

Prototyping-Plattform zur Pose-Erfassung mobiler Geräte mit optischen und Inertialsensoren

2014

WOAR 2014

Workshop on Sensor-Based Activity Recognition (WOAR) <1, 2014, Rostock, Germany>

In diesen Artikel wird eine Prototyping-Plattform zur Erfassung von Position und Orientierung mobiler Geräte mittels verschiedener Sensoren vorgestellt. Nach der Darstellung des Standes der Technik und der Anwendung in unterschiedlichen Bereichen wird die Plattform mit ihren Sensoren beschrieben. Anschließend werden die im Forschungsvorhaben eKon1 bereits entwickelten und geplanten Verfahren vorgestellt. Hierbei wird detailliert auf die Nutzung einer nach oben gerichteten, fischäugigen Kamera (Deckenkamera) eingegangen, um abschließend einen Ausblick auf die zu erwarteten Ergebnisse und Entwicklungen zu geben.

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Steger, Teena; Wesarg, Stefan

Quantitative Analysis of Marker Segmentation for C-Arm Pose Based Navigation

2014

XIII Mediterranean Conference on Medical and Biological Engineering and Computing

The Mediterranean Conference on Medical and Biological Engineering and Computing (MEDICON) <13, 2013, Seville, Spain>

Intraoperative C-arm fluoroscopy is used for better instrument guidance during bronchoscopy. Unfortunately, C-arm images do not provide depth information. But, offering 3D instrument localization would enable faster and more accurate guidance of the bronchoscope. Using the C-arm pose, this can be achieved by combining intraoperative fluoroscopy with a preoperative CT. Thus, the 3D position of the bronchoscope tip inside the bronchial tree can be located and visualized. We developed a marker plate for C-arm pose estimation, which is placed on the patient table. The markers are made of steel and appear in two different shapes: spheres and sticks. Detecting the markers is essential for the C-arm pose estimation method. In this work, we present and evaluate two detection methods for detecting the projected markers on the fluoroscopy images. Tests on cadaver images showed very good results regarding robustness and precision: For circles and lines, 80% and 85%, respectively, of all visible markers were detected, whereas only 1% and 3%, respectively, of all detected markers were missegmented.

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Flach, Guntram; Kubach, Michael; Özmü, Eray; Wehrenberg, Immo

Realisierung von vertrauenswürdigem Cloud-Computing mit SkIDentity: Der Anwendungsfall in Wertschöpfungsketten der Automobilindustrie

2014

44. Jahrestagung der Gesellschaft für Informatik. INFORMATIK 2014

CloudCycle Workshop <2014, Stuttgart, Germany>

Ziel des SkIDentity-Projektes ist es, eine tragfähige Brücke zwischen den sicheren elektronischen Ausweisen (eID) und den heute existierenden bzw. sich entwickelnden Cloud-Computing-Infrastrukturen zu schlagen. Somit können vertrauenswürdige Identitäten für die Cloud bereitgestellt und komplette Prozess- und Wertschöpfungsketten sicher gestaltet werden. Hierfür werden existierende Komponenten, Dienste und Vertrauensinfrastrukturen zu einer umfassenden, rechtskonformen, wirtschaftlich sinnvollen und sicheren Identitätsinfrastruktur für die Cloud integriert und in breitenwirksamen Pilotprojekten erprobt. Eine solche Pilotapplikation ist ein Projektworkspace, der auf die Bedürfnisse der verteilten Wertschöpfungsketten der Automobilindustrie abgestimmt ist. Die SkIDentity-Technologie ermöglicht über einen eID-Broker den verschiedenen an einem Projekt beteiligten Entwicklern eine starke Authentisierung am Projektworkspace mit den unterschiedlichen bereits in ihrem Unternehmen vorhandenen Credentials im Sinne eines föderierten Identitätsmanagements. Diese Arbeit stellt die SkIDentity-Technologie vor und illustriert deren Vorteile anhand der Pilotapplikation.

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Rus, Silvia; Große-Puppendahl, Tobias; Kuijper, Arjan

Recognition of Bed Postures Using Mutual Capacitance Sensing

2014

Ambient Intelligence

European Conference on Ambient Intelligence (AmI) <11, 2014, Eindhoven, The Netherlands>

In recent years, mutual capacitive sensing made significant advances in the field of gathering implicit contextual data. These systems find broad usage in pervasive activity-recognition systems, installed stationary or made portable. In the domain of context recognition new ways of interaction with the environment opened up since conductive objects can be detected under certain conditions at distances up to 50 cm. This paper investigates an approach to recognize bed postures using mutual capacitance sensing. The overall goal is to develop a technological concept that can be applied to recognize bed postures of patients in elderly homes. The use of this contextual data may lead to many desired benefits in elderly care e.g. the better prevention of decubitus ulcer, a condition caused by prolonged pressure on the skin resulting in injuries to skin and underlying tissues. For this, we propose a low-cost grid of crossed wires of 48 measurement points placed between the mattress and the bed sheet. The experimental results analyze a set of five lying positions. We achieved for all tested individuals an accuracy of 80.76% and for several individuals of the same bodysize an accuracy of 93.8%.

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Olbrich, Manuel; Franke, Tobias; Rojtberg, Pavel

Remote Visual Tracking for the (Mobile) Web

2014

Proceedings Web3D 2014

International Conference on 3D Web Technology (WEB3D) <19, 2014, Vancouver, BC, Canada>

Augmented Reality is maturing, but in a world where we are used to straightforward services on the internet, Augmented Reality applications require a lot of preparation before they can be used. Our approach shows how we can bring Augmented Reality into a normal web browser, or even browsers on mobile devices. We show how we are, with recent features of HTML5, able to augment reality based on complex 3D tracking in a browser without having to install or set up any software on a client. With this solution, we are able to extend 3D Web applications with AR and reach more users with a reduced usability barrier. A key contribution of our work is a pipeline for remote tracking built on web-standards.

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Brunton, Alan; Salazar, Augusto; Bolkart, Timo; Wuhrer, Stefanie

Review of Statistical Shape Spaces for 3D Data with Comparative Analysis for Human Faces

2014

Computer Vision and Image Understanding

With systems for acquiring 3D surface data being evermore commonplace, it has become important to reliably extract specific shapes from the acquired data. In the presence of noise and occlusions, this can be done through the use of statistical shape models, which are learned from databases of clean examples of the shape in question. In this paper, we review, analyze and compare different statistical models: from those that analyze the variation in geometry globally to those that analyze the variation in geometry locally. We first review how different types of models have been used in the literature, then proceed to define the models and analyze them theoretically, in terms of both their statistical and computational aspects. We then perform extensive experimental comparison on the task of model fitting, and give intuition about which type of model is better for a few applications. Due to the wide availability of databases of high-quality data, we use the human face as the specific shape we wish to extract from corrupted data.

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Mittelstädt, Sebastian; Bernard, Jürgen; Schreck, Tobias; Steiger, Martin; Kohlhammer, Jörn; Keim, Daniel A.

Revisiting Perceptually Optimized Color Mapping for High-Dimensional Data Analysis

2014

EuroVis - Short Papers 2014

Eurographics Conference on Visualization (EuroVis) <16, 2014, Swansea, Wales, UK>

Colors is one of the most effective visual variables since it can be combined with other mappings and encode information without using any additional space on the display. An important example where expressing additional visual dimensions is direly needed is the analysis of high-dimensional data. The property of perceptual linearity is desirable in this application, because the user intuitively perceives clusters and relations among multi-dimensional data points. Many approaches use two-dimensional colormaps in their analysis, which are typically created by interpolating in RGB, HSV or CIELAB color spaces. These approaches share the problem that the resulting colors are either saturated and discriminative but not perceptual linear or vice versa. A solution that combines both advantages has been previously introduced by Kaski et al.; yet, this method is to date underutilized in Information Visualization according to our literature analysis. The method maps high-dimensional data points into the CIELAB color space by maintaining the relative perceived distances of data points and color discrimination. In this paper, we generalize and extend the method of Kaski et al. to provide perceptual uniform color mapping for visual analysis of high-dimensional data. Further, we evaluate the method and provide guidelines for different analysis tasks.

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Prediger, Mark; Braun, Andreas; Marinc, Alexander; Kuijper, Arjan

Robot-Supported Pointing Interaction for Intelligent Environments

2014

Distributed, Ambient, and Pervasive Interactions

International Conference on Distributed, Ambient and Pervasive Interactions (DAPI) <2, 2014, Heraklion, Crete, Greece>

A natural interaction with appliances in smart environment is a highly desired form of controlling the surroundings using intuitively learned interpersonal means of communication. Hand and arm gestures, recognized by depth cameras, are a popular representative of this interaction paradigm. However they usually require stationary units that limit applicability in larger environments. To overcome this problem we are introducing a self-localizing mobile robot system that autonomously follows the user in the environment, in order to recognize performed gestures independent from the current user position. We have realized a prototypical implementation using a custom robot platform and evaluated the system with various users.

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Eicke, Tim Nicolas; Jung, Yvonne; Kuijper, Arjan

Robust Real-Time Shadows for Dynamic 3D Scenes on the Web

2014

HCI International 2014 - Posters' Extended Abstracts. Proceedings Part I

International Conference on Human-Computer Interaction (HCII) <16, 2014, Heraklion, Crete, Greece>

The authentic display of shadows by modern video games has long become a matter of course. On the web however, this is somewhat different: the rendering of three dimensional scenes in the browser has only in recent years been on the rise. At best, shadows have only played a minor part in that development, despite their importance regarding recognition of spacial relationships in human vision and general increase of a scene's authenticity. An important part in the development of web-based 3D is played by the open-source JavaScript framework X3DOM, as it provides an approach for the integration of declarative 3D in HTML5. However the framework too only offers rudimentary shadow rendering techniques that hardly meet today's demands. This work tackles this issue by first examining existing shadow mapping techniques for their suitability in the web context and based on that developing and implementing a concept for the enhancement of shadow display in X3DOM.

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Vahl, Matthias; Lukas, Uwe von; Schwabe, Claas

SEAKISS - Semantisches Erfassen des Küstensaums für digitale Seekarten

2014

Die Produktion elektronischer Seekarten und Papierkarten erfolgt heute bereits teilweise aus einer gemeinsamen Datenbasis. Hierdurch werden Redundanzen vermieden und die Produktion spezieller Themenkarten beschleunigt. Allerdings ist die Ersterfassung und Aktualisierung dieser Datenbasis unter Verwendung georeferenzierter Orthofotos immer noch ein zeit- und kostenaufwändiger manueller Prozess. In dieser Studie wird untersucht, inwieweit sich Verfahren der Computer Vision zur teilautomatischen Auswertung von Orthofotos einsetzen lassen. Nach der Darstellung der Ausgangssituation, der Anforderungen und Randbedingungen sowie einer Eingrenzung des Testgebietes werden die Aufgaben präzisiert, die zur Beantwortung der Fragestellung bearbeitet werden müssen. Der aktuelle Stand der Wissenschaft und Technik wird präsentiert und hinsichtlich der Aufgabenstellung bewertet. Kern der Studie ist die Herleitung einer fünfstufigen Verarbeitungspipeline, bestehend aus aufeinander folgenden Verarbeitungsschritten. Jeder Schritt wird detailliert beschrieben. Insbesondere wird gezeigt, welche Technologien und Algorithmen der Bildverarbeitung einzusetzen sind. Aufbauend auf dem Vorwissen der Bearbeiter sowie einer gezielten Literaturrecherche wurden verschiedene Technologieexperimente durchgeführt, um die Eignung in Frage kommender Ansätze für die jeweiligen Teilschritte unter Nutzung des relevanten Bildmaterials bewerten zu können. Die Auswertung der Technologieexperimente erlaubt eine fundierte Bewertung der untersuchten Verfahren in den unterschiedlichen Schritten der Pipeline. Einfache Bildverarbeitungsalgorithmen, die auf das Erkennen einzelner Objekte abzielen, erweisen sich für solch komplexe Eingangsdaten als ungeeignet. Es erscheint daher notwendig, durch ein modellbasiertes Verfahren vorhandenes Domänenwissen zu nutzen. Erst die Kombination von Low-Level-Verfahren zur Erkennung mit interpretierenden High- Level-Verfahren verspricht Erfolg. Die Studie beantwortet auch die Frage nach der Art der Wissensrepräsentation - wie kann das Domänenwissen möglichst vollständig abgebildet werden? Mathematische, regelbasierte Verfahren sind für die Vielfalt und große Varianz der zu erkennenden Objekte zu starr und nicht fehlertolerant genug. Neuronale Netze erscheinen weniger geeignet, da sie schnell sehr komplex werden und die Schwäche haben, auf Nichterlerntes stochastisch zu reagieren. Wahrscheinlichkeitsbasierte Ansätze sind dagegen zielführend. Der automatisierte Aufbau des Domänenmodells und dessen Parametrisierung bleiben Gegenstand weiterer Untersuchungen. Die besonderen Randbedingungen, die sich durch die Domäne Seekarte des Küstensaums ergeben, wurden in die Untersuchung aufgenommen. Es wird beispielsweise erörtert, inwieweit sich Standard- Bildverarbeitungsalgorithmen auf große Datenbestände anwenden lassen und wie die Georeferenzierung der erkannten Objekte in die Datenbasis des Produktionssystems zurückgeführt werden kann. Neben den Untersuchungen zu einzelnen Teilschritten wird eine Architektur in Form einer durchgängigen Verarbeitungspipeline vom Einlesen eines Kartenabschnittes, über drei Erkennungsschritte, bis hin zur Ausgabe der gefundenen Geoobjekte vorgeschlagen. Die Studie schließt mit der Empfehlung, diese Architektur in einem Forschungsprojekt umzusetzen und deren Eignung anhand eines größeren Testgebietes und weiterer Objektklassen zu untersuchen.

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Kubach, Michael; Özmü, Eray; Flach, Guntram

Secure Cloud Computing with SkIDentity: A Cloud-Teamroom for the Automotive Industry

2014

Open Identity Summit 2014

Open Identity Summit 2014 <2014, Stuttgart, Germany>

A major security-challenge in the automotive industry is to enable the secure and flexible engineering cooperation with changing partners in complex development projects. Therefore an effective interorganizational identity management is needed to control access to cooperative development platforms. This identity management has to be based on reliable identification of engineers of various partners with different credentials. The SkIDentity-Project, that aims to build trusted identities for the cloud, addresses this scenario. By integrating the existing components, services and trust infrastructures into a comprehensive, legally valid and economically viable identity infrastructure the technology enables to provide trusted identities for the cloud and secure complete business processes and value chains. One pilot-application of the project is the "Cloud-Teamroom for the Automotive Industry". It is adjusted to the specific requirements of the value chains in the automotive industry. Thanks to the SkIDentity-Technology, and via the so-called eID-Broker, engineers from different partners can access the cloud-teamroom. For the required strong authentication they can use the credentials that are already available in their company. This paper presents the SkIDentity-technology and exemplifies it by means of the pilot application.

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Plaza Muñoz, Sergio; Henniger, Olaf [Betreuer]

Security in Smart Grids -- A Demonstrator for the Application of Homomorphic Encryption

2014

Mondragón, Univ, Bachelor Thesis, 2014

New homomorphic encryption methods allow carrying out calculations on encrypted data such that the results after decrypting agree with the results of the corresponding calculations on the unencrypted data. In this way, for instance, consumption data in smart grids, which contains personally identifiable and, therefore, confidential information, can be aggregated without the data being present in clear. The first open source implementations of homomorphic encryption methods are already available, and the goal of the project is to create a homomorphic encryption demonstrator.

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Nazemi, Kawa; Breyer, Matthias; Burkhardt, Dirk; Stab, Christian; Kohlhammer, Jörn

SemaVis: A New Approach for Visualizing Semantic Information

2014

Towards the Internet of Services: The THESEUS Research Program

Information is an indispensable resource today. Access to and interaction with information play more and more a key role, whereas the amount of accessible information increases. Semantic technologies provide new solutions to structure this important property. One promising way to access the complex semantic structures and the huge amount of data is visualization. Today's Semantic Visualization systems offer primarily proprietary solutions for predefined and known users and usage scenarios. The adaptation to other scenarios and users is often cost-and time-consuming. This article presents a novel model for a fully adaptable and adaptive Semantics Visualization framework. Starling with the introduction of a new visualization model, the implementation of this model will be described. The article concludes with selected advantages of the described visualization technology.

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Schmidt, Uwe; Roth, Stefan

Shrinkage Fields for Effective Image Restoration

2014

2014 IEEE Conference on Computer Vision and Pattern Recognition. Proceedings

IEEE Conference on Computer Vision and Pattern Recognition (CVPR) <32, 2014, Columbus, Ohio, USA>

Many state-of-the-art image restoration approaches do not scale well to larger images, such as megapixel images common in the consumer segment. Computationally expensive optimization is often the culprit. While efficient alternatives exist, they have not reached the same level of image quality. The goal of this paper is to develop an effective approach to image restoration that offers both computational efficiency and high restoration quality. To that end we propose shrinkage fields, a random field-based architecture that combines the image model and the optimization algorithm in a single unit. The underlying shrinkage operation bears connections to wavelet approaches, but is used here in a random field context. Computational efficiency is achieved by construction through the use of convolution and DFT as the core components; high restoration quality is attained through loss-based training of all model parameters and the use of a cascade architecture. Unlike heavily engineered solutions, our learning approach can be adapted easily to different trade-offs between efficiency and image quality. We demonstrate state-of-the-art restoration results with high levels of computational efficiency, and significant speedup potential through inherent parallelism.

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Henniger, Olaf; Muramatsu, Daigo; Matsumoto, Takashi; Yoshimura, Isao; Yoshimura, Mitsu

Signature Recognition, Overview

2014

Encyclopedia of Biometrics

A signature is a handwritten representation of a person's name. Writing a signature is the established method for authentication and for expressing deliberate decisions of the signer in many areas of life, such as banking or the conclusion of legal contracts. A closely related concept is a handwritten personal sign depicting something else than a person's name. As compared to text-independent writer recognition methods, signature/sign recognition goes with shorter handwriting probes but requires writing the same name or personal sign every time. Handwritten signatures and personal signs belong to the behavioral biometric characteristics as the person must become active for signing. Regarding the automated recognition of handwritten signatures, there is a distinction between online signatures and offline signatures.

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Henniger, Olaf; Guest, Richard; Miguel-Hurtado, Oscar; Kaplan, Christiane

Signature/Sign Time Series Data: Standardization

2014

Encyclopedia of Biometrics

The International Standard ISO/IEC 19794-7 specifies data interchange formats for online signature data in the form of multidimensional time series representing the signature dynamics. ISO/IEC 19794-7 specifies the following data formats for online signature time series data: a full format applicable in a wide range of application areas where handwritten online signatures or signs are involved, a compression format, a compact format, and an XML-based format. These formats support interoperability and data interchange among the subsystems of open online signature recognition systems.

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Feraco, Antonio; Müller-Wittig, Wolfgang K.

Singapore Policy-Making Processes: The Impact of ICT to Enhance Public Participation and Gather Meaningful Insights

2014

Handbook of Research on Advanced ICT Integration for Governance and Policy Modeling

In Singapore, ICT plays a key role as enabling technology for the most of sectors, several initiatives have been launched to gather insights from these large amounts of data and the utilization of visual solutions as a mean to provide useful insights represents the basis for policy makers' decisions. Further to it Singapore is promoting the usage of new channels of communications to optimise processes of e-Participation, to enhance public inputs in governmental activities and other initiatives to gather insights from geo-spatial, behavioural, commercial, scientific data. The following chapter aims to provide an overview about Singapore IT strategies development and the relation between Government and key-stakeholders to define and establish new policies, governance and the framework implemented through the value add provided by IT and Visual solution ad-hoc utilised.

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Wichmann, Julian L.; Majenka, Pavel; Beeres, Martin; Kromen, Wolfgang; Schulz, Boris; Wesarg, Stefan; Bauer, Ralf W.; Kerl, J. Matthias; Gruber-Rouh, Tatjana; Hammerstingl, Renate; Vogl, Thomas J.; Lehnert, Thomas

Single-portal-phase Low-tube-voltage Dual-energy CT for Short-term Follow-up of Acute Pancreatitis: Evaluation of CT Severity Index, Interobserver Agreement and Radiation Dose

2014

European Radiology

Objectives: To intra-individually compare single-portal-phase low-tube-voltage (100-kVp) computed tomography (CT) with 120-kVp images for short-term follow-up assessment of CT severity index (CTSI) of acute pancreatitis, interobserver agreement and radiation dose. Methods: We retrospectively analysed 66 patients with acute pancreatitis who underwent initial dual-contrast-phase CT (unenhanced, arterial, portal phase) at admission and short-term (mean interval 11.4 days) follow-up dual-contrast-phase dual-energy CT. The 100-kVp and linearly blended images representing 120-kVp acquisition follow-up CT images were independently evaluated by three radiologists using a modified CTSI assessing pancreatic inflammation, necrosis and extrapancreatic complications. Scores were compared with paired t test and interobserver agreement was evaluated using intraclass correlation coefficients (ICC). Results: Mean CTSI scores on unenhanced, portal- and dual-contrast-phase images were 4.9, 6.1 and 6.2 (120 kVp) and 5.0, 6.0 and 6.1 (100 kVp), respectively. Contrast-enhanced series showed a higher CTSI compared to unenhanced images (P<0.05) but no significant differences between single- and dual-contrast-phase series (P>0.7). CTSI scores were comparable for 100-kVp and 120-kVp images (P>0.05). Interobserver agreement was substantial for all evaluated series and subcategories (ICC 0.67-0.93). DLP of single-portal-phase 100-kVp images was reduced by 41 % compared to 120-kVp images (363.8 versus 615.9 mGy cm). Conclusions: Low-tube-voltage single-phase 100-kVp CT provides sufficient information for follow-up evaluation of acute pancreatitis and significantly reduces radiation exposure.

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Silva, Nelson; Settgast, Volker; Eggeling, Eva; Grill, Florian; Zeh, Theodor; Fellner, Dieter W.

Sixth Sense - Air Traffic Control Prediction Scenario Augmented by Sensors

2014

i-KNOW 2014

International Conference on Knowledge Technologies and Data-driven Business (I-KNOW) <14, 2014, Graz, Austria>

This paper is focused on the fault tolerance of Human Machine Interfaces in the field of air traffic control (ATC) by accepting the overall user's body language as input. We describe ongoing work in progress in the project called Sixth Sense. Interaction patterns are reasoned from the combination of a recommendation and inference engine, the analysis of several graph database relationships and from multiple sensor raw data aggregations. Altogether, these techniques allow us to judge about different possible meanings of the current user's interaction and cognitive state. The results obtained from applying different machine learning techniques will be used to make recommendations and predictions on the user's actions. They are currently monitored and rated by a human supervisor.

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Smartwatch analysiert Körperaktivitäten im Schlaf

2014

AGR aktuell - Interdisziplinäre Fachinformationen

Ein Drittel des Tages verbringt der Mensch schlafend auf zwei Quadratmetern. Schlaf ist die wichtigste Erholungsphase für den menschlichen Körper. Immer mehr Menschen leiden jedoch unter Schlafstörungen, die durch physische und psychische Faktoren bedingt sind. Schlafstörungen rühren häufig von der Matratze. Mithilfe von Smartwatches können die Forscher des Fraunhofer IGD zukünftig die Schlafaktivität messen und auf die Schlafqualität schließen.

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Schiel, Ralf; Bieber, Gerald; Thomas, Andreas

Smartwatch und -phone für Therapie-und Monitoring bei Kindern und Jugendlichen mit Typ-1-Diabetes

2014

Diabetologie und Stoffwechsel

Diabetes Kongress (DDG) <49, 2014, Berlin, Germany>

Einleitung: Die häufigste und somit eine der wichtigsten Akutkomplikationen für Kinder und Jugendliche mit Typ-1-Diabetes mellitus sind Hypoglykämien. Sie führen zu Ängsten der Betroffenen und ihrer Angehörigen, beeinträchtigen die Lebensqualität und können zu psychischen Alterationen führen. Die Früherkennung und Prävention von Hypoglykämien ist daher ein vordringliches Ziel der Diabetesbehandlung. Methoden: Smartphones und Smartwatches mit integrierten Beschleunigungssensoren können permanent Bewegungen des Körpers registrieren. Aktivitäten und Muster können durch spezielle Software analysiert und identifiziert werden (Entwicklung: Fraunhofer Institut für Graphische Datenverarbeitung). Hypoglykämien gehen zumeist mit bestimmten Bewegungsabläufen einher. In einer Faesibilty-Studie wurde untersucht, ob Smartphones/Smartwatches bei Kindern und Jugendlichen mit Typ-1-Diabetes Hypoglykämien identifizieren können. Insgesamt 4 Kinder (12 - 18 Jahre) wurden über 3 Tage mit Smartphone/Smartwatch ausgerüstet. Parallel trugen die Patienten ein Gerät zur kontinuierlichen Glukosemessung (CGM, Medtronic GmbH). Ergebnisse: Smartwatches können auch während der Nacht getragen werden. Patienten weisen während des Schlafes spezifische Bewegungsmuster auf. Diese können durch Smartphones/Smartwatches als objektive und quantifizierbare Parameter identifiziert werden. Sie bewerten und beschreiben den Schlafverlauf. Es können so Korrelationsbetrachtungen mit Blutglukosewerten erfolgen. Rückschlüsse auf Hypoglykämien sind möglich. Die mittleren Blutglukosewerte in der Studie betrugen nachts 5,3 ± 2,4 mmol/l, das Minimum lag bei 3,6 mmol/l. Die Feasibility der telemedizinischen Anwendung zur Hypoglykämiedetektion wurde belegt. Um aber ausreichende Zuverlässigkeit und sichere Anwendung im klinischen Bereich zu erreichen, sind weitere kontrollierte Studien erforderlich. Schlussfolgerungen: Die vorliegende Untersuchung belegt die Anwendbarkeit von Bewegungssensoren mit entsprechender Software in Smartphones/Smartwatches. Parameter zur Bewertung der Schlafaktivität und Hypoglykämiedetektion wurden identifiziert. Bis zur klinischen Einsatzfähigkeit, sind allerdings noch weitere Untersuchungen erforderlich.

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Spatial Data Structures for Accelerated 3D Visibility Computation to Enable Large Model Visualization on the Web.

2014

Proceedings Web3D 2014

International Conference on 3D Web Technology (WEB3D) <19, 2014, Vancouver, BC, Canada>

The visualization of massive 3D models is an intensively examined field of research. Due to their rapidly growing complexity of such models, visualisation them in real-time will never be possible through a higher speed of rasterization alone. Instead, a practical solution has to reduce the amount of data to be processed, using a fast visibility determination. In recent years, the combination of Javascript and WebGL raised attention for the possibility of rendering hardware-accelerated 3D graphics directly in the browser. However, when compared to desktop applications, they are still fighting with their disadvantages of a generally slower execution speed, or a downgraded set of functionality. We demonstrate the integration of spatial data structures, computed on the client side, using latest technology trends to mitigate the shortcomings of the 3D Web environment. We employ comparably small bounding volume hierarchies to accelerate our visibility determination, as well as to enable specific culling techniques. This allows for an interactive visualization of such massive 3D data sets. Our in-depth analysis of different data structures and environments shows which combination of data structure and visibility determination techniques are currently the best fit for the Web.

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Le Moan, Steven; Urban, Philipp

Spectral Printing with a CMYKRGB Printer: A Closer Look

2014

22nd Color and Imaging Conference. Final Program and Proceedings

Color and Imaging Conference (CIC) <22, 2014, Boston, MA, USA>

With the advent of multi-channel technologies, printers offer more and more possibilities for spectral reproduction. In order to print a specific color sensation, there are now more degrees of freedom when it comes to combining inks (i.e. more metamerism). In this paper, we take the example of a CMYKRGB printer and propose to visualize the extent of its spectral variability (or degree of metamerism) through the analysis of so-called paramermismatch gamuts. We then evaluate the suitability of the recently proposed LabAB interim connection space in the design of look-up tables for spectral color management. We demonstrate in particular that the spectral variability of this printer is small enough to drastically reduce the number of necessary grid points needed to sample the connection space without loss of perceived quality.

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SRC - A Streamable Format for Generalized Web-based 3D Data Transmission

2014

Proceedings Web3D 2014

International Conference on 3D Web Technology (WEB3D) <19, 2014, Vancouver, BC, Canada>

A problem that still remains with today's technologies for 3D asset transmission is the lack of progressive streaming of all relevant mesh and texture data, with a minimal number of HTTP requests. Existing solutions, like glTF or X3DOM's geometry formats, either send all data within a single batch, or they introduce an unnecessary large number of requests. Furthermore, there is still no established format for a joined, interleaved transmission of geometry data and texture data. Within this paper, we propose a new container file format, entitled Shape Resource Container (SRC). Our format is optimized for progressive, Web-based transmission of 3D mesh data with a minimum number of HTTP requests. It is highly configurable, and more powerful and flexible than previous formats, as it enables a truly progressive transmission of geometry data, partial sharing of geometry between meshes, direct GPU uploads, and an interleaved transmission of geometry and texture data. We also demonstrate how our new mesh format, as well as a wide range of other mesh formats, can be conveniently embedded in X3D scenes, using a new, minimalistic X3D ExternalGeometry node.

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Schwabe, Claas; Vahl, Matthias [Betreuer]; Bieber, Gerald [Betreuer]

Stabilisierung optischer Trackingverfahren durch Inertialsensorik

2014

Rostock, Univ., Master Thesis, 2014

In dieser Arbeit wurde der Einsatz von Inertialsensorik zur Stabilisierung optischer Trackingverfahren untersucht. In der Literatur wurde schon häufig aufgezeigt, dass durch das Nutzen von Inertialsensoren das optische Tracking deutlich verbessert werden kann. Unklar ist jedoch noch, wie genau die Daten der Inertialsensoren optimal genutzt werden können. Dazu gibt es laut einschlägiger Forschungsliteratur verschiedene Möglichkeiten. Hierbei wurde gezeigt, dass in einem inside-out Verfahren eine vollständige Einbringung der Inertialdaten in Form von Translationsbeschleunigungen und Rotationsgeschwindigkeiten in den Zustandsvektor der Bewegungsschätzung dem Nutzen von ausschließlich der gemessenen Rotationsgeschwindigkeiten überlegen ist. Für eine outside-in Anordnung ist dem Autor solch eine Untersuchung nicht bekannt. Aufgrund der komplementären Eigenschaften der beiden Anordnungen, können die Ergebnisse der inside-out Anordnung jedoch nicht ohne Weiteres auf die outside-in Anordnung übertragen werden. In dieser Arbeit wurde deshalb untersucht, ob eine vollständige Einbringung der Inertialdaten ebenfalls die besten Resultate bringt. Hierzu wurde ein inertial-visueller Tracker entwickelt. Neben der Frage, welche Daten der Inertialsensoren und wie genau diese zur Stabilisierung optischer Trackingverfahren genutzt werden können, ist weiterhin die Datenanbindung der Sensoren zu einer gemeinsamen Verarbeitungseinheit essentiell für die Echtzeitfähigkeit eines optisch-inertialen Trackingsystems. Das verwendete Kommunikationsprotokoll muss ebenfalls echtzeitfähig sein. Das heißt, es muss ein deterministisches Zeitverhalten aufweisen. Zu diesem Zweck wurden in dieser Arbeit die Protokolle Bluetooth, ZigBee und 802.11g auf ihre prinzipielle Echtzeiteignung untersucht und experimentell bestätigt, dass sie out-of-the-box nicht echtzeitfähig sind, sondern entsprechende Mechanismen in der Anwendungsschicht implementiert werden müssen.

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Steiger, Martin; May, Thorsten; Kohlhammer, Jörn

Stable Incremental Layouts for Dynamic Graph Visualizations

2014

IADIS International Journal on Computer Science and Information Systems

In this paper we present a set of extension techniques to stabilize interactive dynamic graph layout algorithms. It works with different existing Focus & Context methods. We first deal with the initial placement of newly inserted nodes to mitigate acting forces in the layout algorithm. Then, their influence on the existing layout is gradually increased to create a smooth transition between the old and the new layout. To complement this approach we use a look-ahead strategy that integrates additional nodes in the layout to stabilize the layout even more. Our approach is validated using both quantitative and qualitative measures.

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Ullrich, Torsten; Fellner, Dieter W.

Statistical Analysis on Global Optimization

2014

MCSI 2014

International Conference on Mathematics and Computers in Sciences and in Industry (MCSI) <2014, Varna, Bulgaria>

The global optimization of a mathematical model determines the best parameters such that a target or cost function is minimized. Optimization problems arise in almost all scientific disciplines (operations research, life sciences, etc.). Only in a few exceptional cases, these problems can be solved analytically-exactly, so in practice numerical routines based on approximations have to be used. The routines return a result - a so-called candidate of a global minimum. Unfortunately, the question whether the candidate represents the optimal solution, often remains unanswered. This article presents a simple-to-use, statistical analysis that determines and assesses the quality of such a result. This information is valuable and important - especially for practical application.

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Ettl, Anne-Sophie; Kuijper, Arjan

Text and Image Area Classification in Mobile Scanned Digitised Documents

2014

International Journal of Applied Pattern Recognition

Post processing and automatic interpretation of images plays an increasingly important role in the mobile area. Both for the efficient compression and for the automatic evaluation of text, it is useful to store text content as textual information rather than as graphics information. For this purpose pictures from magazines are recorded with the camera of a smartphone and classified according to text and image areas. In this work established desktop procedures are presented and analysed in terms of their applications on mobile devices. Based on these methods, an approach for image segmentation and classification on mobile devices is developed, taking into account the limited resources of these mobile devices.

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Aderhold, Andreas; Wilkosinska, Katarzyna; Corsini, Massimiliano; Jung, Yvonne; Graf, Holger; Kuijper, Arjan

The Common Implementation Framework as Service - Towards Novel Applications for Streamlined Presentation of 3D Content on the Web

2014

Design, User Experience, and Usability. Proceedings Part II

International Conference on Design, User Experience and Usability (DUXU) <3, 2014, Heraklion, Crete, Greece>

We solve a standing issue of the recently published Common Implementation Framework (CIF) for Online Virtual Museums: programmatic access to the transcoding, optimization and template rendering infrastructure of the CIF. We propose a method that enables researchers and developers to build novel systems on top of the CIF infrastructure beyond its current Cultural Heritage workflow. Therefore, we introduce a way to programmatically access the powerful backend of the CIF through a universal access layer, addressable by standards like HTTP and the JSON Data Interchange Format. In order to demonstrate our approach, we present two different use cases in which the CIF pipeline is utilized as a service through the proposed resource-based access layer: a native mobile iOS application for browsing 3D model repositories realizing just-in-time optimization of large models, and a MeshLab plugin to asynchronously convert and prepare a model for the Web.

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Sonntagbauer, Susanne; Sonntagbauer, Peter; Nazemi, Kawa; Burkhardt, Dirk

The FUPOL Policy Lifecycle

2014

Handbook of Research on Advanced ICT Integration for Governance and Policy Modeling

The purpose of this chapter is to outline an advanced policy lifecycle, the FUPOL model with its ability to link technical features in the area of policy modeling. The FUPOL Policy Lifecycle is based on six stages, which are further divided into ten main tasks. These main tasks are split up into eighteen subtasks to provide a very detailed policy lifecycle structure. The detailed breakdown allows to link each task to various technical features, such as opinion maps, policy indicator dashboard, knowledge data base, simulation and visualization tools. It is further argued that the methodology applied is future proof and has the potential of accommodating new technologies in the future.

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Santos, Pedro; Peña Serna, Sebastian; Stork, André; Fellner, Dieter W.

The Potential of 3D Internet in the Cultural Heritage Domain

2014

3D Research Challenges in Cultural Heritage

Europe is rich in cultural heritage but unfortunately much of the tens of millions of artifacts remain in archives. Many of these resources have been collected to preserve our history and to understand their historical context. Nevertheless, CH institutions are neither able to document all the collected resources nor to exhibit them. Additionally, many of these CH resources are unique, and will be on public display only occasionally. Hence, access to and engagement with this kind of cultural resources is important for European culture and the legacy of future generations. However, the technology needed to economically mass digitize and annotate 3D artifacts in analogy to the digitization and annotation of books and paintings has yet to be developed. Likewise approaches to semantic enrichment and storage of 3D models along with meta-data are just emerging. This paper presents challenges and trends to overcome the latter issues and demonstrates latest developments for annotation of 3D artifacts and their subsequent export to Europeana, the European digital library, for integrated, interactive 3D visualization within regular web browsers taking advantage of technologies such as WebGl and X3D.

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Samartzidis, Timotheos; Busch, Christoph [Betreuer]; Damer, Naser [Betreuer]

Three Dimensional Scanning of Clothes, for Simulation and Presentation Purposes in a Virtual Fitting Room

2014

Darmstadt, Hochschule, Master Thesis, 2014

The aim of this thesis is to develop a low-cost semi-professional automated 3D scanning and post-production system for digitizing clothing and apparel for in shop and online presentation purposes. Ultimately giving birth to a database of digitized 3d models of apparel to enable virtual-fitting rooms and real-time fitting feedback. In the first part different scanning methods are tested if they are suited for scanning apparel and if the quality is good enough for advertisement and presentation purposes. The cost of the system is also taken into account. The thesis then identifies the best and most cost effective approach and tries to develop and automate the method using state of the art consumer products. In the main section the thesis describes the functionality of the method and how it can be applied. Different algorithms and workflows are shown and combined to develop the automated system. In conclusion the thesis describes and summarizes the system and opens up how it could be implemented in a consumer oriented presentation like a virtual fitting room or an online shopping style advisor using the users body-metrics.

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Sturm, Werner; Berndt, René; Halm, Andreas; Ullrich, Torsten; Eggeling, Eva; Fellner, Dieter W.

Time-based Visualization of Large Data-Sets. An Example in the Context of Automotive Engineering

2014

International Journal on Advances in Software

Automotive systems can be very complex when using multiple forms of energy. To achieve better energy efficiency, engineers require specialized tools to cope with that complexity and to comprehend how energy is spread and consumed. This is especially essential to develop hybrid systems, which generate electricity by various available forms of energy. Therefore, highly specialized visualizations of multiple measured energies are needed. This paper examines several three-dimensional glyphbased visualization techniques for spatial multivariate data. Besides animated glyphs, two-dimensional visualization techniques for temporal data to allow detailed trend analysis are considered as well. Investigations revealed that Scaled Data-Driven Spheres are best suited for a detailed 3D exploration of measured data. To gain a better overview of the spatial data, Cumulative Glyphs are introduced. For trend analysis, Theme River and Stacked Area Graphs are used. All these visualization techniques are implemented as a web-based prototype without the need of additional web browser plugins using X3DOM and Data-Driven Documents.

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Towards a Tighter Coupling of Visualization and Public Policy Making

2014

IEEE Conference on Visual Analytics Science and Technology. Proceedings

IEEE Symposium on Visual Analytics Science and Technology (VAST) <9, 2014, Paris, France>

The purpose of this ongoing work is to motivate public policy making as an application area for information visualization and visual analytics. Through our expertise gathered in several policy making related projects, we identified parallels between the benefits of visualization and the needs of evidence-based public policy making. In the following, we will share our previous work consisting of the conceptual introduction of information visualization and visual analytics into the application field of public policy making. Moreover, we will show two real-world cases applying this concept. Finally, we will share identified challenges to be addressed by the information visualization and visual analytics domains in the future.

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Bernard, Jürgen; Hutter, Marco; Sessler, David; Schreck, Tobias; Behrisch, Michael; Kohlhammer, Jörn

Towards a User-Defined Visual-Interactive Definition of Similarity Functions for Mixed Data

2014

IEEE Conference on Visual Analytics Science and Technology. Proceedings

IEEE Symposium on Visual Analytics Science and Technology (VAST) <9, 2014, Paris, France>

The creation of similarity functions based on visual-interactive user feedback is a promising means to capture the mental similarity notion in the heads of domain experts. In particular, concepts exist where users arrange multivariate data objects on a 2D data landscape in order to learn new similarity functions. While systems that incorporate numerical data attributes have been presented in the past, the remaining overall goal may be to develop systems also for mixed data sets. In this work, we present a feedback model for categorical data which can be used alongside of numerical feedback models in future.

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Braun, Andreas; Schmidt, Sönke; Kuijper, Arjan; Neumann, Stephan; Wichert, Reiner

Towards Interactive Car Interiors - the Active Armrest

2014

NordiCHI '14

Nordic Conference on Human-Computer Interaction (NordiCHI) <8, 2014, Helsinki, Finland>

Modern cars are often equipped with touch-based interaction systems, such as touchscreens or touchpads. However, they are typically exposed within the car environment. In this paper, we present the Active Armrest. This regular car armrest is equipped with capacitive proximity sensors that combine limb detection and recognition of gestures. The sensors are designed for invisible integration into existing environments and can be used to create interactive surfaces in a car. We investigate two different types of gestural interaction, touch gestures with the arm lifted and free-air finger gestures performed above the interactive area, while the arm stays on the armrest. The system was integrated into a prototype and tested for gesture recognition precision and usability.

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Bader, Sebastian; Aehnelt, Mario

Tracking Assembly Processes and Providing Assistance in Smart Factories

2014

ICAART 2014, Vol. 1

International Conference on Agents and Artificial Intelligence (ICAART) <6, 2014, Angers, France>

Tracking assembly processes is a necessary prerequisite to provide assistance in smart factories. In this paper, we show how to track the construction of complex components. For this we employ formal task models as background knowledge and simple sensors like RFIDs. The background knowledge is converted into a probabilistic model that actually tracks the process. As a result, we are able to provide assistance in smart factories. We discuss the performance of the approach, as well as potential applications.

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Steger, Sebastian; El Hakimi, Wissam; Wesarg, Stefan

Tracking von Instrumenten auf fluoroskopischen Aufnahmen für die navigierte Bronchoskopie

2014

Bildverarbeitung für die Medizin 2014

Workshop Bildverarbeitung für die Medizin (BVM) <2014, Aachen, Germany>

Intraoperative C-Bogen-Fluoroskopie dient bei der bronchoskopischen Biopsie zur Lokalisation des Bronchoskops und der Biospiezange innerhalb des Patiententhorax. Bei bekannter C-Bogen Pose ist es möglich, aus der 2D-Position der Instrumentenspitze auf der Fluoroskopie deren 3D-Position innerhalb des Bronchialbaums zu berechnen. Während die Pose mit Hilfe einer Markerplatte auf dem Patiententisch bestimmt werden kann, fehlt bisher eine automatische Verfolgung der Instrumentenspitze auf der kontinuierlichen Fluoroskopie. In dieser Arbeit wird eine solche Tracking-Methode vorgestellt und evaluiert. Erste Experimente an einem Bronchialbaum-Phantom lieferten sehr robuste und präzise Ergebnisse und auch die Echtzeitfähigkeit konnte gezeigt werden.

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Bieber, Gerald; Schiel, Ralf; Vahl, Tobias

Treatment Support of Obese Adolescents in Horne Environments by Activity Recognition

2014

WOAR 2014

Workshop on Sensor-Based Activity Recognition (WOAR) <1, 2014, Rostock, Germany>

Overweight and obesity are the main risk factors for many secondary disorders (including diabetes mellitus). The number of ill people is increasing and beside this, the diseases are leading to personal and socioeconomic burdens. Accepted treatments are known as structured treatment and teaching programs (SBSP). Even the treatment is very efficient; a long-term follow-up after participation in the SBSP is missing. This leads to loss of effectiveness of about 70% in the long-term perspective. A new approach for efficient and effective follow-up is the use of interactive telemedicine technologies. Hereby smartphones and smartwatches are used in the home environment to assist and motivate the patients. The sensors of the electronic devices are tracking physical activity or food intake, and the psychologist analyses the patient's habits and invents if necessary. This approach is analyzed in the present study.

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Two-Step FEM-Based Liver-CT Registration: Improving Internal and External Accuracy

2014

Medical Imaging 2014: Image Processing

SPIE Medical Imaging Symposium <2014, San Diego, CA, USA>

To know the exact location of the internal structures of the organs, especially the vasculature, is of great importance for the clinicians. This information allows them to know which structures/vessels will be affected by certain therapy and therefore to better treat the patients. However the use of internal structures for registration is often disregarded especially in physical based registration methods. In this paper we propose an algorithm that uses finite element methods to carry out a registration of liver volumes that will not only have accuracy in the boundaries of the organ but also in the interior. Therefore a graph matching algorithm is used to find correspondences between the vessel trees of the two livers to be registered. In addition to this an adaptive volumetric mesh is generated that contains nodes in the locations in which correspondences were found. The displacements derived from those correspondences are the input for the initial deformation of the model. The first deformation brings the internal structures to their final deformed positions and the surfaces close to it. Finally, thin plate splines are used to refine the solution at the boundaries of the organ achieving an improvement in the accuracy of 71%. The algorithm has been evaluated in CT clinical images of the abdomen.

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Krepp, Stefan; Kuijper, Arjan [Betreuer]; Braun, Andreas [Betreuer]

Unsichtbare Erkennung von Berührungen über akustisches Tracking

2014

Darmstadt, TU, Master Thesis, 2014

Die unsichtbare Integration von Eingabegeräten in die natürliche Umgebung der Nutzer ist eine große Herausforderung, die allerdings große Chancen bietet. Allgegenwärtige Eingabegeräte besitzen das Potential gewohnte Interaktionsmuster zu durchbrechen. Eingabegeräte wie klassische Fernbedienungen für Fernseher könnten bald der Vergangenheit angehören. Ein Türöffner für unsichtbare Benutzerschnittstellen sind akustische Sensoren, die sich kostengünstig und einfach installieren lassen und fast jede Oberfläche zu einem Eingabegerät machen können. In dieser Arbeit wurde ein akustisches Berührungserkennungssystem entwickelt, das die Erkennung und Unterscheidung verschiedener Impact-Gesten und Wischgesten ermöglicht und sich unsichtbar in bestehende Möbel integriert. Dabei wurde ein bestehender Ansatz erweitert. Erste Nutzerstudien unterstreichen die Machbarkeit des verfolgten Ansatzes. Zudem konnte gezeigt werden, dass akustische Berührungserkennung einen Mehrwert für andere Technologien bedeuten kann. So konnte gezeigt werden, dass die Interaktionsgeschwindigkeit eines kapazitiven Gestenerkennungssystems durch die Integration akustischer Berührungserkennung erhöht werden kann.

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Fastnacht, Claas; Urban, Bodo [Betreuer]; Aehnelt, Mario [Betreuer]

Unterstützung kooperativer Arbeitsprozesse durch Mehrbedienerassistenz

2014

Rostock, Univ., Bachelor Thesis, 2014

In dieser Arbeit wurde der aktuelle Stand von Technik und Wissenschaft zusammengefasst. Dabei wurden Anforderungen für mobile Assistenzsysteme erarbeitet, sowie aktuelle Konzepte auf ihre Eignung für weitere Arbeiten geprüft. Grundlage dafür waren unter anderen psychologischen Betrachtungen. Diese konnten zeigen, dass Teams grundsätzlich bessere Ergebnisse liefern, insbesondere wenn sie eigenverantwortlich arbeiten können. Außerdem wurden offizielle und inoffizielle Kommunikation eingeführt sowie deren Bedeutung erörtert. Des Weiteren wurden grundlegende Kooperationsformen im Bereich des CSCW zusammengetragen sowie vorhandene Frameworks vorgestellt. Für mobile Geräte konnten zusammengefasst folgende Anforderungen erarbeitet werden: - Kontextsensitivität, bzw. Anpassung an den Nutzer - Einfache Bedienung - Portabilität - Robustheit Aus den überprüften Konzepten könnten folgende Aspekte Relevanz für spätere Arbeiten haben: - Zugriff auf historische Daten bzw. frühere Arbeiten an bestimmten Geräten oder Orten ( Erleichterung der Wartung) - Direkte Kommunikation durch Audio/Video-Konferenzen - Identifikation von Geräten, Maschinen oder Orten durch RFID-Tags ( lokalisierte Kontexterkennung) - Priorisierung von Aufträgen ( Optimierung, Planungsänderung ) Keines der Konzepte kann jedoch alle Anforderungen erfüllen, insbesondere waren keinerlei Ansätze zur Kombination von Arbeitsgruppen und Montageassistenz auffindbar. Daher war es nötig, ein solches Konzept zu erarbeiten und umzusetzen. Zur Entwicklung des Konzepts wurden zunächst Einsatzszenarien und Anforderungen für die Assistenz entwickelt und daraus das Konzept erarbeitet. Ziel war es, Kommunikation und Koordination zu verbessern, um die Arbeiten effizienter und besser erledigen zu können. Die Umsetzung erfolgte mit Fokus auf das ausführende Personal, also Arbeiter und Vorarbeiter. Hierbei wurden die wichtigsten Funktionen erfolgreich implementiert.

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User Friedly Calibration and Tracking for Optical Stereo See-Through Augmented Reality

2014

IEEE International Symposium on Mixed and Augmented Reality - Science & Technology 2014

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <13, 2014, Munich, Germany>

Optical see through head mounted displays (OST-HMD) are ever since the first days of Augmented Reality (AR) in focus of development and in nowadays first affordable and prototypes are spread out to markets. Despite common technical problems, such as having a proper field of view, weight, and other problems concerning the miniaturization of these systems, a crucial aspect for AR relies also in the calibration of such a device with respect to the individual user for proper alignment of augmentations. Our demonstrator shows a practical solution for this problem along with a fully featured example application for a typical maintenance use case based on a generalized framework for application creation. We depict the technical background and procedure of the calibration, the tracking approach considering the sensors of the device, user experience factors, and its implementation procedure in general. We present our demonstrator using an Epson Moverio BT-200 OST-HMD.

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Gottschämmer, Patrick; Große-Puppendahl, Tobias [1. Gutachter]; Kuijper, Arjan [Betreuer]

User Location Modeling Based on Heterogeneous Data Sources

2014

Darmstadt, TU, Bachelor Thesis, 2014

Over the past decade, interest in home automation systems constantly grew. Especially in the daily life with the connection of intelligent everyday devices through the Internet of Things. To allow automatic actions on these devices, user localization systems have become a major input modality for smart home systems. The location of a user (or rather a subject) can be determined by different localization techniques, such as sensitive floor systems, discrete activity sensors like light switches or RSSI-based WLAN/Bluetooth beacons (e.g. smartphones). These heterogeneous data sources provide various means of user location certainty, the ability to identify a user or the ability to recognize multiple subjects in the same location. In order to achieve a higher grade of accuracy, multiple data sources can be combined by location fusioning algorithms. However, to allow the integration of such algorithms on hardware independent basis, a common user location model is needed, which can represent all important aspects of these localization techniques. Furthermore, the overall system needs to be easily extendable with new methods of localization. This Bachelor thesis will investigate the concepts of existing user localization systems as well as develop a new model to represent the location of subjects based on already existing location models. A reference implementation will be provided based on Eclipse SmartHome, an open source building automation framework. The implementation integrates multiple data sources within the Living Lab of Fraunhofer IGD, in particular a capacitive localization system, intelligent light switches and WLAN beacons. Furthermore, a simple location fusioning algorithm will be presented based on the implemented user location model as a proof of concept.

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User Similarity and Deviation Analysis for Adaptive Visualizations

2014

Human Interface and the Management of Information. Proceedings Part I

International Conference on Human Interface and the Management of Information (HIMI) <2014, Heraklion, Crete, Greece>

Adaptive visualizations support users in information acquisition and exploration and therewith in human access of data. Their adaptation effect is often based on approaches that require the training by an expert. Further the effects often aim to support just the individual aptitudes. This paper introduces an approach for modeling a canonical user that makes the predefined training-files dispensable and enables an adaptation of visualizations for the majority of users. With the introduced user deviation algorithm, the behavior of individuals can be compared to the average user behavior represented in the canonical user model to identify behavioral anomalies. The further introduced similarity measurements allow to cluster similar deviated behavioral patterns as groups and provide them effective visual adaptations.

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Kirchbuchner, Florian; Kuijper, Arjan [Betreuer]; Große-Puppendahl, Tobias [Betreuer]

User Tracking and Behavior Recognition Based on a Capacitive Indoor Localization System

2014

Darmstadt, TU, Master Thesis, 2014

This thesis focused on tracking and analyzing the behavior of elderly people by using in-home monitoring systems. The goal was to add a localization component to an existing system for fall detection as well as to assess the elderly's acceptance of such systems and the corresponding loss of privacy. Therefore, this thesis analyzed the demands on monitoring and technical assistance systems and discussed different models of acceptance measuring. Furthermore, existing approaches to user tracking and behavior analysis are examined. On this basis, an implementation of the tracking functionality, based on a capacitive sensor system, was proposed and evaluated. In addition, a survey among elderly people was conducted by the author and the results are presented in detail. The findings of this thesis showed that capacitive sensing in combination with particle filtering was suitable for user tracking. Moreover, the results of the study emphasized that senior citizens were indeed willing to accept a certain loss of privacy but distinguished between different services and systems. It was also shown that the capacitive system used for this study was received positively in comparison to other systems.

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User-Based Visual-Interactive Similarity Definition for Mixed Data Objects - Concept and First Implementation

2014

WSCG 2014. Communication Papers Proceedings

International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision (WSCG) <22, 2014, Plzen, Czech Republic>

The definition of similarity between data objects plays a key role in many analytical systems. The process of similarity definition comprises several challenges as three main problems occur: different stakeholders, mixed data, and changing requirements. Firstly, in many applications the developers of the analytical system (data scientists) model the similarity, while the users (domain experts) have distinct (mental) similarity notions. Secondly, the definition of similarity for mixed data types is challenging. Thirdly, many systems use static similarity models that cannot adapt to changing data or user needs. We present a concept for the development of systems that support the visual-interactive similarity definition for mixed data objects emphasizing 15 crucial steps. For each step different design considerations and implementation variants are presented, revealing a large design space. Moreover, we present a first implementation of our concept, enabling domain experts to express mental similarity notions through a visual-interactive system. The provided implementation tackles the different-stakeholders problem, the mixed data problem, and the changing requirements problem. The implementation is not limited to a specific mixed data set. However, we show the applicability of our implementation in a case study where a functional similarity model is trained for countries as objects.

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Sessler, David; Kuijper, Arjan [Betreuer]; Bernard, Jürgen [Betreuer]

User-centered Interactive Similarity Definition for Complex Data Objects

2014

Darmstadt, TU, Bachelor Thesis, 2014

The definition of similarity between data objects plays a key role for the applicability of many analytical systems. Similarity measures are used for prominent data analysis tasks like nearest neighbor search, clustering, or pattern recognition. These tasks are applied in many scientific domains like Information Retrieval, Data Mining, Machine Learning, Information Visualization and Visual Analytics. The data used for the calculation of similarity can either be of uniform attribute type (like numerical, ordinal, categorical or binary) or consist of combinations thereof (mixed data). The process of similarity definition comprises several challenges which I aim to tackle in this work. To start with, in many applications the developers (data experts) of the analytical system are not necessarily the users (domain experts) of the system. A problem arises, because data experts implement the functional similarity specification for domain experts. The functional similarity specification, however, should reflect the similarity notion in the minds of domain experts. Therefore the domain experts should be involved in the similarity generation process. The second challenge refers to the similarity definition for mixed data. A variety of similarity definitions for numerical, categorical or binary data exist. However, the similarity definition based on mixed data is cumbersome because of the complexity of the data. Finally, there are two possibilities when the similarity can be defined, namely at compile time or at run time. Today, many analytical systems define the similarity at compile time. However, the similarity notion of domain experts or the data set may vary over time. This would require a new specification of the functional similarity and a new compilation of the system. The definition of similarity at run time would solve this problem. I present a visual-interactive system that enables domain experts to define a similarity measure that reflects their similarity notion. The system is applicable for mixed data sets. Domain experts can align objects in a visual interface to generate feedback. Dynamic recalculation of the functional similarity specification allows to match the similarity notion of domain expert at run time. This way the functional similarity specification can be adjusted at any time. Further, I provide a visual-interactive mode which enables the data expert to explore the similarity definition process of the domain expert. In addition, I evaluate the system to assess the quality of the similarity concept as well as the feedback generation process. The results of the evaluation illustrate both: the validity of my solution as well as extension possibilities depending on the complexity of the given user feedback. In two case studies I show the applicability of the system. Both use cases show that the 'mental' similarity notion of users can be captured by the similarity concept. The results of the evaluation and the observations made in the case studies can be applied to improve the system or be used as a baseline for future approaches for user-centered interactive similarity definition for complex data objects.

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Aehnelt, Mario; Gutzeit, Enrico; Urban, Bodo

Using Activity Recognition for the Tracking of Assembly Processes: Challenges and Requirements

2014

WOAR 2014

Workshop on Sensor-Based Activity Recognition (WOAR) <1, 2014, Rostock, Germany>

Activity recognition helps to improve the quality of assistance applications by enabling adaptive and purposeful user support. However, industrial applications require a far more robust recognition in order to ensure process reliable operations. The paper highlights specific challenges and requirements with respect to activity recognition from the perspective of assembly workplaces in manufacturing. A task-oriented assembly model is used to derive human activities based on sensorial observations of work equipment and material.

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Gollmer, Sebastian T.; Kirschner, Matthias; Buzug, Thorsten M.; Wesarg, Stefan

Using Image Segmentation for Evaluating 3D Statistical Shape Models Built With Groupwise Correspondence Optimization

2014

Computer Vision and Image Understanding

Statistical shape models (SSMs) are a well-established tool in medical image analysis. The most challenging part of SSM construction, which cannot be solved trivially in 3D, is the establishment of corresponding points, so-called landmarks. A popular approach for solving the correspondence problem is to minimize a groupwise objective function using the optimization by re-parameterization approach. To this end, several objective functions, optimization strategies and re-parameterization functions have been proposed. While previous evaluation studies focused mainly on the objective function, we provide a detailed evaluation of different correspondence methods, objective functions, re-parameterization, and optimization strategies. Moreover and contrary to previous works, we use distance measures that compare landmark shape vectors to the original input shapes, thus adequately accounting for correspondences which undersample certain regions of the input shapes. Additionally, we segment binary expert segmentations to benchmark SSMs constructed from different correspondences. This new evaluation technique overcomes limitations of the correspondence based evaluation and allows for directly quantifying the influence of the correspondence on the expected segmentation accuracy. From our evaluation results we identify pitfalls of the current approach and derive practical recommendations for implementing a groupwise optimization pipeline.

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Braun, Andreas; Cieslik, Silvana; Zmugg, René; Wichert, Reiner; Klein, Peter; Havemann, Sven; Wagner, Tobias

V2me - Virtuelles Coaching für Senioren

2014

Wohnen - Pflege - Teilhabe. Besser leben durch Technik

Ambient Assisted Living (AAL) <7, 2014, Berlin, Germany>

Eine Herausforderung von alternden Gesellschaften ist die zunehmende Vereinsamung älterer Personen. Als Folge von Todesfällen im sozialen Umkreis, zunehmend mobilen Familien, oder den Wechsel in eine betreute Wohneinrichtung ändern sich die Möglichkeiten zur sozialen Interaktion - die empfundene Einsamkeit nimmt zu. Dies kann sowohl Psyche als auch Physis deutlich belasten. Im Rahmen des Projekts V2me wurde eine Trainingsplattform entwickelt, die über verschiedene technische Geräte in der Lage ist, immersive, virtuelle Trainingslektionen wiederzugeben, die auf verschiedene Webdienste zugreifen können. In einem ersten Schritt wurde diese Plattform speziell darauf zugeschnitten, eine individuelle und digitale Variante des Friendship Enrichment Programs bereitzustellen. Dieses Interventionsprogramm für Senioren vermittelt in Gruppensitzungen Fähigkeiten, die den Teilnehmern ermöglichen neue soziale Kontakte zu gewinnen und bestehende Kontakte besser zu pflegen. In diesem Beitrag stellen wir die technische Infrastruktur vor, und beschreiben im Detail wie diese zu den vorgestellten Zielen beiträgt.

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Vogel, Christoph; Roth, Stefan; Schindler, Konrad

View-Consistent 3D Scene Flow Estimation over Multiple Frames

2014

Computer Vision - ECCV 2014. Proceedings Part IV

European Conference on Computer Vision (ECCV) <13, 2014, Zurich, Switzerland>

We propose a method to recover dense 3D scene flow from stereo video. The method estimates the depth and 3D motion field of a dynamic scene from multiple consecutive frames in a sliding temporal window, such that the estimate is consistent across both viewpoints of all frames within the window. The observed scene is modeled as a collection of planar patches that are consistent across views, each undergoing a rigid motion that is approximately constant over time. Finding the patches and their motions is cast as minimization of an energy function over the continuous plane and motion parameters and the discrete pixel-to-plane assignment. We show that such a view-consistent multi-frame scheme greatly improves scene flow computation in the presence of occlusions, and increases its robustness against adverse imaging conditions, such as specularities. Our method currently achieves leading performance on the KITTI benchmark, for both flow and stereo.

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Siegmund, Dirk; Samartzidis, Timotheos; Damer, Naser; Nouak, Alexander; Busch, Christoph

Virtual Fitting Pipeline: Body Dimension Recognition, Cloth Modeling, and On-Body Simulation

2014

VRIPHYS 14: 11th Workshop in Virtual Reality Interactions and Physical Simulations

International Workshop in Virtual Reality Interaction and Physical Simulations (VRIPHYS) <11, 2014, Bremen, Germany>

This paper describes a solution for 3D clothes simulation on human avatars. The proposed approach consists of three parts, the collection of anthropometric human body dimensions, cloths scanning, and the simulation on 3D avatars. The simulation and human machine interaction has been designed for application in a passive In- Shop advertisement system. All parts have been evaluated and adapted under the aim of developing a low-cost automated scanning and post-production system. Human body dimension recognition was achieved by using a landmark detection based approach using both two 2D and 3D cameras for front and profile images. The human silhouettes extraction solution based on 2D images is expected to be more robust to multi-textured background surfaces than existing solutions. Eight measurements corresponding to the norm of body dimensions defined in the standard EN-13402 were used to reconstruct a 3D model of the human body. The performance is evaluated against the ground-truth of our newly acquired database. For 3D scanning of clothes, different scanning methods have been evaluated under apparel, quality and cost aspects. The chosen approach uses state of the art consumer products and describes how they can be combined to develop an automated system. The scanned cloths can be later simulated on the human avatars, which are created based on estimation of human body dimensions. This work concludes with software design suggestions for a consumer oriented solution such as a virtual fitting room using body metrics. A number of future challenges and an outlook for possible solutions are also discussed.

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Sevilmis, Neyir; Gorecky, Dominic

Virtuelles Montagetraining durch nahtlose Integration von Produkt- und Produktionsdaten

2014

ProSTEP iViP Symposium 2014

ProSTEP iViP Symposium <2014, Berlin, Germany>

Virtuelles Montagetraining weist ein hohes Potential auf, Zeit und Kosten hinsichtlich des Trainings an physikalischen Prototypen für Montageprozesse inner- und außerhalb der Automobilindustrie zu reduzieren. Wir präsentieren ein System-Design-Ansatz für virtuelles Training anhand des spielbasierten Lernansatzes, der dem Benutzer prozedurales Montagewissen auf spielerische Art und Weise vermittelt. Dieser Ansatz wird im Rahmen des EUFP7 Projekts VISTRA erprobt.

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Visual Access to an Agent-based Simulation Model to Support Political Decision Making

2014

i-KNOW 2014

International Conference on Knowledge Technologies and Data-driven Business (I-KNOW) <14, 2014, Graz, Austria>

Decision making in the field of policy making is a complex task. On the one hand conflicting objectives influence the availability of alternative solutions for a given problem. On the other hand economic, social, and environmental impacts of the chosen solution have to be considered. In the political context, these solutions are called policy options. To tackle societal problems a thorough analysis of policy options needs to be executed before a policy can be put into practice. Computational simulation is a method considered for measuring the impacts of policy options. However, due to their complexity, the underlying models and their output may be difficult to access by decision makers. In this work, we present a visual-interactive interface for an agent-based simulation model that enables decision makers to evaluate the impacts of alternative policy options in the field of regional energy planning. The decision maker can specify different subsidy strategies for supporting public photovoltaic installations as input and evaluate their impact on the actual adoption via the simulation output. We show the usability and usefulness of the visual interface in a real-world example evolved from the European research project ePolicy.

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Lenz, Olav; Keul, Frank; Bremm, Sebastian; Hamacher, Kay; Landesberger, Tatiana von

Visual Analysis of Patterns in Multiple Amino Acid Mutation Graphs

2014

IEEE Conference on Visual Analytics Science and Technology. Proceedings

IEEE Symposium on Visual Analytics Science and Technology (VAST) <9, 2014, Paris, France>

Proteins are essential parts in all living organisms. They consist of sequences of amino acids. An interaction with reactive agent can stimulate a mutation at a specific position in the sequence. This mutation may set off a chain reaction, which effects other amino acids in the protein. Chain reactions need to be analyzed, as they may invoke unwanted side effects in drug treatment. A mutation chain is represented by a directed acyclic graph, where amino acids are connected by their mutation dependencies. As each amino acid may mutate individually, many mutation graphs exist. To determine important impacts of mutations, experts need to analyze and compare common patterns in these mutations graphs. Experts, however, lack suitable tools for this purpose. We present a new system for the search and the exploration of frequent patterns (i.e., motifs) in mutation graphs. We present a fast pattern search algorithm specifically developed for finding biologically relevant patterns in many mutation graphs (i.e., many labeled acyclic directed graphs). Our visualization system allows an interactive exploration and comparison of the found patterns. It enables locating the found patterns in the mutation graphs and in the 3D protein structures. In this way, potentially interesting patterns can be discovered. These patterns serve as starting point for a further biological analysis. In cooperation with biologists, we use our approach for analyzing a real world data set based on multiple HIV protease sequences.

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Behrisch, Michael; Davey, James; Fischer, Fabian; Thonnard, Olivier; Schreck, Tobias; Keim, Daniel A.; Kohlhammer, Jörn

Visual Analysis of Sets of Heterogeneous Matrices Using Projection-Based Distance Functions and Semantic Zoom

2014

Computer Graphics Forum

Eurographics Conference on Visualization (EuroVis) <16, 2014, Swansea, Wales, UK>

Matrix visualization is an established technique in the analysis of relational data. It is applicable to large, dense networks, where node-link representations may not be effective. Recently, domains have emerged in which the comparative analysis of sets of matrices of potentially varying size is relevant. For example, to monitor computer network traffic a dynamic set of hosts and their peer-to-peer connections on different ports must be analysed. A matrix visualization focused on the display of one matrix at a time cannot cope with this task. We address the research problem of the visual analysis of sets of matrices. We present a technique for comparing matrices of potentially varying size. Our approach considers the rows and/or columns of a matrix as the basic elements of the analysis. We project these vectors for pairs of matrices into a low-dimensional space which is used as the reference to compare matrices and identify relationships among them. Bipartite graph matching is applied on the projected elements to compute a measure of distance. A key advantage of this measure is that it can be interpreted and manipulated as a visual distance function, and serves as a comprehensible basis for ranking, clustering and comparison in sets of matrices. We present an interactive system in which users may explore the matrix distances and understand potential differences in a set of matrices. A flexible semantic zoom mechanism enables users to navigate through sets of matrices and identify patterns at different levels of detail. We demonstrate the effectiveness of our approach through a case study and provide a technical evaluation to illustrate its strengths.

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Steiger, Martin; Bernard, Jürgen; Mittelstädt, Sebastian; Lücke-Tieke, Hendrik; Keim, Daniel A.; May, Thorsten; Kohlhammer, Jörn

Visual Analysis of Time-Series Similarities for Anomaly Detection in Sensor Networks

2014

Computer Graphics Forum

Eurographics Conference on Visualization (EuroVis) <16, 2014, Swansea, Wales, UK>

We present a system to analyze time-series data in sensor networks. Our approach supports exploratory tasks for the comparison of univariate, geo-referenced sensor data, in particular for anomaly detection. We split the recordings into fixed-length patterns and show them in order to compare them over time and space using two linked views. Apart from geo-based comparison across sensors we also support different temporal patterns to discover seasonal effects, anomalies and periodicities. The methods we use are best practices in the information visualization domain. They cover the daily, the weekly and seasonal and patterns of the data. Daily patterns can be analyzed in a clustering-based view, weekly patterns in a calendar-based view and seasonal patterns in a projection-based view. The connectivity of the sensors can be analyzed through a dedicated topological network view. We assist the domain expert with interaction techniques to make the results understandable. As a result, the user can identify and analyze erroneous and suspicious measurements in the network. A case study with a domain expert verified the usefulness of our approach.

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Visual Correlation Analysis to Explain Open Government Data based on Linked-Open Data for Decision Making

2014

International Journal of Digital Society

Public authorities normally consider statistical data about indicators in their decision makings. Such valid kind of data allows an objective observation about indicator developments over time. In case of a significant deviation from the normal indicator level, it is difficult to understand the reasons for upcoming problems. In this article we present an approach that allows an enhanced information gathering through an improved information overview about the depending aspects to such an indicator by considering governmental data-sources that provide also other types of data than just statistics. Even more, our approach integrates a system that allows generating explanations for Open Government Data, especially to specific indicators, based on Linked-Open Data and shows it in graphical form to enable a fast overview gathering. This allows decision-makers to get hints for unexpected reasons of concrete problems that may influence an indicator.

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Visual Explanation of Government-Data for Policy Making through Open-Data Inclusion

2014

International Conference for Internet Technology and Secured Transactions

International Conference for Internet Technology and Secured Transactions (ICITST) <9, 2014, London, UK>

Commonly, data used in public authorities are statistical data about certain indicator. Such valid kind of data allows an objective observation about indicator developments over time. In case of a significant deviation from the normal indicator level, it is difficult to understand the reasons for upcoming problems. In our paper we present an approach that allows an enhanced information gathering through an improved information overview about the depending aspects to such an indicator by considering governmental data-sources that provide also other types of data than just statistics. Even more, our approach integrates a system that allows generating explanations for Open Government Data, especially to specific indicators, based on Linked-Open Data. This enables decision-makers to get hints for unexpected reasons of concrete problems that may influence an indicator.

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Heß, Martin; Bremm, Sebastian; Weissgraeber, Stephanie; Hamacher, Kay; Goesele, Michael; Wiemeyer, Josef; Landesberger, Tatiana von

Visual Exploration of Parameter Influence on Phylogenetic Trees

2014

IEEE Computer Graphics and Applications

Evolutionary relationships between organisms are represented as phylogenetic trees inferred from multiple sequence alignments (MSAs). The proposed approach clusters trees created with many MSA parameterizations. It displays the chosen parameters' impact on the phylogenetic trees. This view offers interactive parameter exploration and automatic identication of relevant parameters.

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Kühnel, Hannes; Kuijper, Arjan [Betreuer]; Maier, Sebastian [Betreuer]; May, Thorsten [Betreuer]

Visual Interactive Process Monitoring

2014

Darmstadt, TU, Bachelor Thesis, 2014

In this work, a visual analytics tool is developed which enables automatic analysis of processes, which are defined by the user, of monitoring systems. This tool provides reports of the performance and sequence of process steps and allows a more detailed analysis of user interactions. Based on technologies of visual analytics and information visualization, data sets can be analyzed and presented visually for deeper analysis. This includes a directed node-link diagram, that represents the process model and diagrams for metadata such as the performance of each step. The objective is to be able to handle even large amounts of data and to compare a state of the process with the desired process state. The incoming data are event data consisting of logs from events which represent process steps used in a process containing a timestamp and other information like e.g. money or duration. The problem which has to be solved is to handle the information extracted from event data and to find complex, direct and indirect relations between process steps by giving an overview using a node-link diagram with weighted edges to represent the transitions from one process step to another and providing interaction techniques. Additional the information has to be analyzed according to chosen indicators (e.g. duration or money) and to compare different types of process runs with each other, e.g. separating complete and incomplete runs, to possibly find these relations which can be indicators for an incomplete run. As a result the tool gives the ability to choose different runs to compare them and simultaneously compares the chosen indicators. Furthermore, the tool was evaluated to find out, if it is possible to solve this problems by using this tool.

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Visual Process Support to Assist Users in Policy Making

2014

Handbook of Research on Advanced ICT Integration for Governance and Policy Modeling

The policy making process requires the involvement of various stakeholders, who bring in very heterogeneous experiences and skills concerning the policy making domain, as well as experiences of ICT solutions. Current solutions primary designed to provide "one-solution-fits-all", which in most cases fail the needs of all stakeholders. In this paper we introduce a new approach to assist users based on their tasks. Therefore the system observes the interaction of the user and recognizes the current phase of the policy making process and the profile of the user to assist him more sufficiently in solving his task. For this purpose the system automatically enables or disables supporting features such as visualization, tools and supporting techniques.

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Visual-interactive Exploration of Interesting Multivariate Relations in Mixed Research Data Sets

2014

Computer Graphics Forum

Eurographics Conference on Visualization (EuroVis) <16, 2014, Swansea, Wales, UK>

The analysis of research data plays a key role in data-driven areas of science. Varieties of mixed research data sets exist and scientists aim to derive or validate hypotheses to find undiscovered knowledge. Many analysis techniques identify relations of an entire dataset only. This may level the characteristic behavior of different subgroups in the data. Like automatic subspace clustering, we aim at identifying interesting subgroups and attribute sets. We present a visual-interactive system that supports scientists to explore interesting relations between aggregated bins of multivariate attributes in mixed data sets. The abstraction of data to bins enables the application of statistical dependency tests as the measure of interestingness. An overview matrix view shows all attributes, ranked with respect to the interestingness of bins. Complementary, a node-link view reveals multivariate bin relations by positioning dependent bins close to each other. The system supports information drill-down based on both expert knowledge and algorithmic support. Finally, visual-interactive subset clustering assigns multivariate bin relations to groups. A list-based cluster result representation enables the scientist to communicate multivariate findings at a glance. We demonstrate the applicability of the system with two case studies from the earth observation domain and the prostate cancer research domain. In both cases, the system enabled us to identify the most interesting multivariate bin relations, to validate already published results, and, moreover, to discover unexpected relations.

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Burkhardt, Dirk; Nazemi, Kawa; Encarnação, José Daniel; Retz, Wilhelm; Kohlhammer, Jörn

Visualization Adaptation Based on Environmental Influencing Factors

2014

Human-Computer Interaction: Part 1

International Conference on Human-Computer Interaction (HCII) <16, 2014, Heraklion, Crete, Greece>

Working effectively with computer-based devices is challenging, especially under mobile conditions, due to the various environmental influences. In this paper a visualization adaptation approach is described, to support the user under discriminatory environmental conditions. For this purpose, a context model for environmental influencing factors is being defined. Based on this context model, an approach to adapt visualizations in regards of certain environmental influences is being evolved, such as the light intensity, air quality, or heavy vibrations.

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Lenz, Olav; Landesberger, Tatiana von [Prüfer]; Kuijper, Arjan [Betreuer]

Visueller Vergleich von Ausfall-Effekten in mehreren Datensätzen

2014

Darmstadt, TU, Master Thesis, 2014

Es ist einige Jahre her, seitdem die Finanzkrise begonnen hat und die weltweiten Finanznetzwerke zu wackeln begannen. Politik und Unternehmen machten große Versprechungen, die Stabilität der Finanznetzwerke zu verbessern und die Finanzmärkte stärker zu reglementieren. Jetzt stellen sich die Fragen, ob sich wirklich etwas verändert hat, ob sich so etwas heute wiederholen könnte und wie stark die Auswirkungen wären. Auch angesichts der aktuellen Eurokrise sind Fragestellungen, welche die Stabilität der weltumspannenden Finanznetzwerke betreffen, hoch relevant. Zur Beurteilung, ob Maßnahmen die gewünschten Erfolge bringen, ist die Untersuchung der Entwicklung dieser Netzwerke über die Zeit besonders interessant. Mit Hilfe der bestehenden Systeme [Die11, vLDBF13] und [Len12] lassen sich viele Fragestellungen in Bezug auf Ausfall- Effekte in Finanzsystemen beantworten. Dabei ist es möglich, die Ausfall-Effekte mit verschiedenen Parametern zu simulieren und die Ergebnisse mit Hilfe visueller Analyse zu analysieren. Der Schwerpunkt liegt bei diesen Systemen allerdings auf der Simulation und Analyse eines einzelnen Finanznetzwerks. Einen direkten Vergleich von mehreren Finanzsystemen ermöglichen diese Systeme nicht. In Rahmen dieser Arbeit wird, auf der Basis der bereits existierenden Systeme [Die11, vLDBF13, Len12] und [LKB+14], ein System entwickelt, dass die Ausfall-Effekte von zwei oder mehr Netzwerken miteinander vergleichen kann. Dieser Vergleich von mehreren Datensätzen soll die Analyse von Zeitreihen bzw. Vergleichsgruppen ermöglichen. Dies kann beispielsweise dabei helfen zu untersuchen, wie sich die Auswirkungen der Ausfall-Effekte über einen Zeitraum hinweg verändert haben. Dazu wird eine Analysepipeline entwickelt, welche die Analyse vereinfacht und die Beantwortung der Fragestellungen unterstützt. Der Schwerpunkt liegt auf der Betrachtung von Ähnlichkeiten und Unterschieden in den Ausfall-Effekten. Dabei ist die Verwendung geeigneter Vergleichsansätze wichtig, um in einer großen Menge an Ausfall- Effekt-Graphen Ähnlichkeiten zu finden und näher untersuchen zu können. Als Basis für den Vergleich werden sowohl bekannte knoten- und musterbezogene Informationen, als auch strukturelle und metrikbasierte Vergleiche von Graphen herangezogen. Neben den Finanznetzwerken wird in dieser Arbeit auch eine andere Anwendungsdomäne beschrieben. Die Untersuchung von Sequenzen aus Aminosäuren und dort stattfindenden Mutationen stellt für die Biologie einen sehr wichtigen Forschungsbereich dar. Solche Untersuchungen werden beispielsweise benötigt, um geeignete Medikamente gegen Viruserkrankungen zu entwickeln. Die dort auftretenden Mutationsgraphen sind mit den Ausfall-Effekt-Graphen in Finanznetzwerken vergleichbar. Aus diesem Grund lassen sich die Konzepte sehr gut übertragen.

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Bender, Jan [Ed.]; Kuijper, Arjan [Betreuer]; Landesberger, Tatiana von [Ed.]; Theisel, Holger [Ed.]; Urban, Philipp [Betreuer]; Fellner, Dieter W. [Betreuer]; Goesele, Michael [General Chair]; Roth, Stefan [General Chair]

VMV 2014

2014

Workshop on Vision, Modeling, and Visualization (VMV) <19, 2014, Darmstadt, Germany>

VMV is a unique event that brings together scientists and practicioners interested in the interdisciplinary fields of computer vision and computer graphics, with special emphasis on the link between the disciplines. It offers researchers the opportunity to discuss a wide range of different topics within an open, international and interdisciplinary environment, and has done so successfully for many years.

  • 978-3-905674-74-3
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Bockholt, Ulrich; Behr, Johannes; Wagner, Sebastian; Limper, Max; Olbrich, Manuel; Franke, Tobias

VR/AR-Technologien im Browser: Effiziente Integration virtueller Technologien ins PDM-Umfeld durch Nutzung von Web-Technologien

2014

17. IFF-Wissenschaftstage 2014. Tagungsband

IFF-Wissenschaftstage <17, 2014, Magdeburg, Germany>

Die Verknüpfung von Web-Technologien und VT-Technologien ermöglicht es, sehr schnell und sehr effizient, schlanke und aufgabenspezifischen Anwendungen zu entwickeln, die über HTML-Interfaces auf PDM-Systeme zugreifen. Diese Anwendungen können gut gewartet, modifiziert und erweitert werden, weil für die Anpassung lediglich HTML-Kenntnisse benötigt werden. Durch die vorgestellten Technologien können Virtual und Augmented Reality Technologien in den Web-Browser gebracht werden und Interfaces können geschaffen werden, durch die VR/AR direkt auf PDM Daten zugreifen kann. Damit können die Workflows in industriellen Anwendungen unterstützt werden und die Akzeptanz der Technologien kann in den Unternehmen gestärkt werden.

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Leissner, Johanna; Kilian, Ralf; Fuhrmann, Constanze; Anstetter, Florian; Naumovic, Tina; Haefner, Klaus; Janis, Katrin

Wie der Klimawandel die Königsschlösser bedroht

2014

Aviso

Unser bauliches Kulturerbe ist in besonderer Weise von den Auswirkungen des Klimawandels betroffen. Denn viel stärker als in der Vergangenheit besteht die Gefahr, dass es durch rasant fortschreitende Korrosionsprozesse angegriffen wird. Korrosion stellte zwar schon immer eine Gefahr für Materialien aller Art wie auch für die Substanz historischer Gebäude dar. Aber mit dem prognostizierten weltweiten Anstieg der Umgebungstemperaturen nehmen die chemischen Reaktionen, die für solche zersetzenden Prozesse verantwortlich sind, an Fahrt auf. Dem liegt die exponentielle Arrhenius-Beziehung zwischen Reaktionsgeschwindigkeit und Temperatur zugrunde: Bei einem Temperaturanstieg um 10 Grad verdoppeln derartige Reaktionen ihre Zerstörungskraft. Doch nicht nur die Korrosionsgefahr baulicher Substanz nimmt mit dem Klimawandel zu. In Küstennähe, besonders in den Niederlanden, wächst die Bedrohung durch einen steigenden Meeresspiegel. Allgemein steigt das Risiko, dass Bauten in ihrer Struktur oder an ihrer Außenseite von Überflutungen, Stürmen oder Starkregen schwerer geschädigt werden als bisher. Vor allem im nördlichen Europa erhöht sich damit die Gefahr von Schimmelpilzwachstum.

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Adachi, Seiji; Brandstätt, Peter; Herget, Wolfgang; Leistner, Philip; Landersheim, Volker; Weber, Daniel; Mueller-Roemer, Johannes

Wind Tunnel Test and CFD/CAA Analysis on a Scaled Model of a Nose Landing Gear

2014

Greener Aviation. Clean Sky Breakthroughs and Worldwide Status

Conference "Greener Air" <2014, Brussels, Belgium>

In work package 2.2.4 "NLG Low-Noise Enabling Technologies" of the Clean Sky GRA LNC project, the Fraunhofer Institute proposes hubcaps for reducing noise from a nose landing gear (NLG) as the most promising solution. The purpose of this paper is to prove the effect of the hubcaps experimentally and numerically. A simplified and 1:5-scaled model of a NLG was first created by the rapid prototyping technique together with hubcaps that can cover both the outer and inner hub cavities. Noise radiated from various NLG configurations with and without hubcaps were measured during they were placed in the wind tunnel. In the configuration without hubcaps, two major noise peaks in addition to a continuous spectrum were observed in the direction parallel to the wheel axle. When the inner hubcaps were attached to the NLG, the levels of the peaks were significantly reduced. The outer caps have no effects on the noise reduction. Nearly the same noise spectrum as the original no-hubcap configuration was observed. Although the peaks were not clearly observed in the direction perpendicular to the axle, the same noise reduction could be recognized in the inner-hubcap configuration. In the numerical examination, a stationary CFD analysis with a k-\\'0f turbulence model was first performed and a CAA analysis was then carried out based on Lighthill's aeroacoustic analogy after reconstructing a time-varying turbulent flow by a stochastic noise generation and radiation model. In the CAA analysis of the no-hubcap configuration, a strong fluctuation in the right and left inner hub cavities, where pressure is oscillating alternately, was observed. This fluctuation served as a dipole noise source whose direction is parallel to the wheel axle. The simulated spectrum of far field sound pressure in this direction has the peaks corresponding to the ones experimentally observed. In the hubcap configuration, the pressure fluctuation in the inner hubcap cavities was greatly reduced. Because of this, the noise peaks were well depressed. Due to the dipole characteristics of the noise source, no clear peaks were simulated in the far field spectrum in the direction perpendicular to the axle. In conclusion, the effectiveness of the inner hubcaps has been proved in the wind tunnel experiment and confirmed in the numerical analysis. The mechanism of noise reduction by the inner caps has also been clarified.

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Bieber, Gerald [Betreuer]; Aehnelt, Mario [Betreuer]; Urban, Bodo [Betreuer]

WOAR 2014

2014

Workshop on Sensor-Based Activity Recognition (WOAR) <1, 2014, Rostock, Germany>

The first workshop on sensor-based activity recognition in Rostock- Warnemünde, WOAR 2014, brought together scientists, interested parties and users. It provided an opportunity to exchange experiences and present best practices as well as technical and scientific results. The participants dealt with different technologies for the recognition of physical activity with the help of inertial sensor systems (acceleration sensors, gyroscope etc.) and also their practical application. The present publication contains the contributions to the workshop. They reflect the current state of science and technology concerning specific technologies and applications in the fields of (occupational) health, lifestyle change and quantified self as well as production, maintenance and service.

  • 978-3-8396-0792-3
  • 3-8396-0792-2
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Ventura, Jonathan; Wagner, Daniel; Kurz, Daniel; Wuest, Harald; Benhimane, Selim

Workshop on Tracking Methods & Applications

2014

IEEE International Symposium on Mixed and Augmented Reality - Science & Technology 2014

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <13, 2014, Munich, Germany>

The focus of this workshop is on all issues related to tracking for mixed and augmented reality applications. Unlike the tracking sessions of the main conference, this workshop does not require pure novelty of the proposed methods; it rather encourages presentations that concentrate on complete systems and integrated approaches engineered to run in real-world scenarios. The research felds covered include self-localization using computer vision or other sensing modalities (such as depth cameras, GPS, inertial, etc.) and tracking systems issues (such as system design, calibration, estimation, fusion, etc.). This year's focus is also expanded to research on object detection and semantic scene understanding with relevance to augmented reality. Implementations on mobile devices and under real-time constraints are also part of the workshop focus. These are issues of core importance for practical augmented reality systems.