Liste der Fachpublikationen

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Reinert, David; Humm, Bernhard (Betreuer); Rapp, Stefan (Betreuer); Jung, Florian (Betreuer)

Quantitative Analyse von Krebstumor-Bildmerkmalen aus CT-Aufnahmen des Kopf-Nacken-Bereichs

2017

Darmstadt, Hochschule, Bachelor Thesis, 2017

Korrekte Prognosen und Diagnosen im Bezug auf Krebserkrankungen stellen Ärzte auch heute noch vor eine große Herausforderung. Keine phänotypische Ausprägung eines Krebstumors gleicht einer anderen. Auch unterscheidet sich der Krankheitsverlauf bei jedem Patienten signifkant. Deshalb ist es notwendig die Behandlung für jeden Patienten zu individualisieren. Ziel dieser Arbeit war es, mit Hilfe von Radiomics zu untersuchen, ob Korrelationen zwischen Krebstumor-Bildmerkmalen und patientenspezifschen Informationen bestehen. Hierfür wurden Segmentierung und Feature-Extraktion durch eine implementierte Extraktions-Software für 38 CT-Bild-Datensätze des menschlichen Kopf-Nacken-Bereichs durchgeführt, um diese anschließend mit den zur Verfügung gestellten Meta-Daten des Patienten auf lineare Korrelation zu untersuchen. Wir konnten bei 17,54% der von uns extrahierten Radiomics eine starke Korrelation feststellen. 22,33% der Merkmale korrelierten mittelstark. Außerdem bestätigt die von uns verwendete Methodik bereits in der Medizin bekannte Korrelationen. Obwohl eine kleine Datenmenge untersucht wurde, sind die ersten Ergebnisse vielversprechend, müssen jedoch durch weitere Untersuchungen validiert werden.

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Knuth, Martin; Fellner, Dieter W. (Betreuer); Bender, Jan (Betreuer)

Realistic Visualization of Accessories within Interactive Simulation Systems for Garment Prototyping

2017

Darmstadt, TU, Diss., 2017

In virtual garment prototyping, designers create a garment design by using Computer Aided Design (CAD). In difference to traditional CAD the word "aided" in this case refers to the computer replicating real world behavior of garments. This allows the designer to interact naturally with his design. The designer has a wide range of expressions within his work. This is done by defining details on a garment which are not limited to the type of cloth used. The way how cloth patterns are sewn together and the style and usage of details of the cloth's surface, like appliqués, have a strong impact on the visual appearance of a garment to a large degree. Therefore, virtual and real garments usually have a lot of such surface details. Interactive virtual garment prototyping itself is an interdisciplinary field. Several problems have to be solved to create an efficiently usable real-time virtual prototyping system for garment manufacturers. Such a system can be roughly separated into three sub-components. The first component deals with acquisition of material and other data needed to let a simulation mimic plausible real world behavior of the garment. The second component is the garment simulation process itself. Finally, the third component is centered on the visualization of the simulation results. Therefore, the overall process spans several scientific areas which have to take into account the needs of each other in order to get an overall interactive system. In my work I especially target the third section, which deals with the visualization. On the scientific side, the developments in the last years have shown great improvements on both speed and reliability of simulation and rendering approaches suitable for the virtual prototyping of garments. However, with the currently existing approaches there are still many problems to be solved, especially if interactive simulation and visualization need to work together and many object and surface details come into play. This is the case when using a virtual prototyping in a productive environment. The currently available approaches try to handle most of the surface details as part of the simulation. This generates a lot of data early in the pipeline which needs to be transferred and processed, requiring a lot of processing time and easily stalls the pipeline defined by the simulation and visualization system. Additionally, real world garment examples are already complicated in their cloth arrangement alone. This requires additional computational power. Therefore, the interactive garment simulation tends to lose its capability to allow interactive handling of the garment. In my work I present a solution, which solves this problem by moving the handling of design details from the simulation stage entirely to a completely GPU based rendering stage. This way, the behavior of the garment and its visual appearance are separated. Therefore, the simulation part can fully concentrate on simulating the fabric behavior, while the visualization handles the placing of surface details lighting, materials and self-shadowing. Thus, a much higher degree of surface complexity can be achieved within an interactive virtual prototyping system as can be done with the current existing approaches.

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Rixels: Towards Secure Interactive 3D Graphics in Engineering Clouds

2017

Lukas, Uwe von (Ed.) et al.: Go-3D 2017: Mit 3D Richtung Maritim 4.0 : Tagungsband zur Konferenz Go-3D 2017. Stuttgart: Fraunhofer Verlag, 2017, pp. 25-43

Go-3D <8, 2017, Rostock, Germany>

Cloud computing rekindles old and imposes new challenges on remote visualization especially for interactive 3D graphics applications, e.g., in engineering and/or in entertainment. In this paper we present and discuss an approach entitled 'rich pixels' (short 'rixels') that balances the requirements concerning security and interactivity with the possibilities of hardware accelerated post-processing and rendering, both on the server side as well as on the client side using WebGL.

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Hafner, Morris; Kuijper, Arjan (Betreuer); Limper, Max (Betreuer)

Robust and Efficient Bijective Parameterization

2017

Darmstadt, TU, Bachelor Thesis, 2017

The goal of this thesis was to create a novel algorithm for bijective parameterizations of 3D triangle meshes with disk topology. Existing methods are either fast, but create non-bijective parameterizations, or are too slow to be applied to bigger meshes like high-resolution 3D scans or video game levels. We show an approach to transform an arbitrary, potentially non-bijective parameterization into a bijective mapping. The results show that the new algorithm produces results that are at least competitive with existing bijective parameterizers and still has room for future improvements.

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Wen, Zhuoman; Wang, Yanjie; Luo, Jun; Kuijper, Arjan; Di, Nan; Jin, Minghe

Robust, Fast and Accurate Vision-Based Localization of a Cooperative Target Used for Space Robotic Arm

2017

Acta Astronautica, Vol.136 (2017), pp. 101-114

When a space robotic arm deploys a payload, usually the pose between the cooperative target fixed on the payload and the hand-eye camera installed on the arm is calculated in real-time. A high-precision robust visual cooperative target localization method is proposed. Combing a circle, a line and dots as markers, a target that guarantees high detection rates is designed. Given an image, single-pixel-width smooth edges are drawn by a novel linking method. Circles are then quickly extracted using isophotes curvature. Around each circle, a square boundary in a pre-calculated proportion to the circle radius is set. In the boundary, the target is identified if certain numbers of lines exist. Based on the circle, the lines, and the target foreground and background intensities, markers are localized. Finally, the target pose is calculated by the Point-3-Perspective algorithm. The algorithm processes 8 frames per second with the target distance ranging from 0.3m to 1.5 m. It generated highprecision poses of above 97.5% on over 100,000 images regardless of camera background, target pose, illumination and motion blur. At 0.3 m, the rotation and translation errors were less than 0.015° and 0.2 mm. The proposed algorithm is very suitable for real-time visual measurement that requires high precision in aerospace.

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Mettel, Matthias Ruben; Alekseew, Michael; Stocklöw, Carsten; Braun, Andreas

Safety Services in Smart Environments Using Depth Cameras

2017

Braun, Andreas (Ed.) et al.: Ambient Intelligence : 13th European Conference, AmI 2017. Springer, 2017. (Lecture Notes in Computer Science (LNCS) 10217), pp. 80-93

European Conference on Ambient Intelligence (AmI) <13, 2017, Malaga, Spain>

Falls of elderly persons are the most common cause of serious injuries in this age group. It is important to detect the fall in a timely manner. If medical help can't be provided immediately a deterioration of the patient's state may occur. In order to tackle this challenge, we want to propose two combined safety services that can utilize the same sensor to prevent and detect falls. The Dangerous Object Adviser detects small obstacles located on the floor and warns the user about the stumbling hazard when the user walks in their direction. The Fall Detection Service detects a fall and informs caregivers. This enables the caregivers to provide medical care in time. Both services are implemented by using the Microsoft Kinect, with the obstacles extracted from the depth image and the usage of skeleton tracking gives to provide the necessary information on the user position and pose.

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Bieber, Gerald; Seidel, Robert; Portwich, Rene

SARA - Subjective and Objective Data Acquisition for Physiotherapy Treatment Support

2017

Association for Computing Machinery (ACM): Proceedings of the 10th International Conference on PErvasive Technologies Related to Assistive Environments : PETRA 2017. New York: ACM, 2017. (ACM International Conference Proceedings Series (ICPS) 448), pp. 403-407

ACM International Conference on PErvasive Technologies Related to Assistive Environments (PETRA) <10, 2017, Island of Rhodes, Greece>

The work of physiotherapists is very important for the cure of patients. Physiotherapy has a long historical background. Physiotherapists are working almost manually, treat pain and movement restrictions, support rehabilitation and support the recovering of strength and wellbeing. The healing of the patients is a slow process and subjective impressions about pain or discomfort are important for the quality and adjustment of the treatment. The quality of treatment is dependent by the skills and knowledge of the therapist. Unfortunately, objective indicators of a good or successful treatment in the area of physiotherapy are rare; a comprehensive documentation after the therapy is often missing. With SARA, a platform for physiotherapy treatment support, the physiotherapist have received a new tool that allows an objective assessment of the treatment progress, the condition of their patients, and a documentation about the physical performance and further needs. This paper describes the concept and the measurement methods for the unobtrusive monitoring of the treatment quality and the results of the therapy.

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Search Intention Analysis for Task- and User-Centered Visualization in Big Data Applications

2017

Procedia Computer Science [online], Vol.104 (2017), pp. 539-547

International Conference on Tissue Engineering (ICTE) <2016, Riga, Latvia>

A new approach for classifying users' search intentions is described in this paper. The approach uses the parameters: word frequency, query length and entity matching for distinguishing the user's query into exploratory, targeted and analysis search. The approach focuses mainly on word frequency analysis, where different sources for word frequency data are considered such as the Wortschatz frequency service by the University of Leipzig and the Microsoft Ngram service (now part of the Microsoft Cognitive Services). The model is evaluated with the help of a survey tool and few machine learning techniques. The survey was conducted with more than one hundred users and on evaluating the model with the collected data, the results are satisfactory. In big data applications the search intention analysis can be used to identify the purpose of a performed search, to provide an optimal initially set of visualizations that respects the intended task of the user to work with the result data.

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Sajenko, Andrej; Letschert, Thomas (Betreuer); Krämer, Michel (Betreuer)

Seminaturliche Abfragesprache fur GeoDaten

2017

Gießen, TH Mittelhessen, Master Thesis, 2017

Diese Arbeit befasst sich mit der Entwicklung einer seminatürlichen Abfragesprache, mit welcher Merkmale eines geografischen Features beschrieben werden. Das Suchverhalten wird so verändert, dass gesuchte Begriffe semantisch verglichen werden. Der Vergleich zwischen Wörtern des Benutzers und den Bezeichnern des Indexes wird auf den Wortstamm und deren Synonyme verallgemeinert, um dem Benutzer mehr Freiheiten in der Wortwahl zu geben. Die Abfragesprache besteht aus einer Teilmenge an natürlichsprachlichen, einfachen Sätzen und bietet die Möglichkeit einfache Eingrenzungen der Ergebnisse vorzunehmen. Der Benutzer wird durch das Interface mittels Vorschlagen und Vervollständigungen unterstutzt, um die Syntax richtig zu treffen. Die Einbeziehung der Synonyme stellt sich als sinnvoll heraus. Dies regt dazu an weitere Beziehungen wie die Holonyme zu nutzen um den semantischen Vergleich weiter auszubauen. Eine pragmatische Losung für einfache Abfragen mit konjugierten Bedingungen liefert die seminatürliche Abfragesprache. Für einen professionellen Einsatz ist die Sprache unzureichend, da diese keine logischen "und" und "oder" Verknüpfungen zulasst. Die Eingabeunterstützung sorgt dafür, dass Benutzer ihre Abfragen durch die Auswahl der Vorschläge strukturell zusammenstellen können ohne einen syntaktischen Fehler zu erhalten.

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Madapur Devraj, Sudeep Dev; Kraus, Dieter (Betreuer); Siegmund, Dirk (Betreuer)

Separation of Subjects in High-Security Locks by Using Capacitive Sensing

2017

Bremen, Hochschule, Master Thesis, 2017

A reliable distinction between one and more than one person in the automated access control is of great importance. When access to high-security area e.g. bank or in border control, here personal interlock is used. These systems ensure without human influence, that only a single individual can pass through a particular transit area (Mantrap Portal). Existing technical approaches use thermal imaging (Body Heat), RGB-D Images, Camera image based and computer vision algorithm to verify if there are one or more persons in the transit area. Other known systems use weight or photo sensor based methods for verification. In this Master's Thesis, we will investigate using capacitive sensors for this application. The most suitable capacitive sensing technique, as well as the number of sensors and their position, will be examined in this work. The performance of the developed system will be measured empirical testing and includes test scenarios in which an attacker tries to spoof the system. The system performance using capacitive sensors will be measured. Receiver operating characteristics (ROC) or Detection Error Tradeoff (DET) curves will show how the developed system performs compared with other solution. The work will conclude with a feasibility analysis of the capacitive sensor technique in a possible practical usage.

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Merz, Johannes; Kuijper, Arjan (Betreuer); Getto, Roman (Betreuer)

Simplified Definition of Parameter Spaces of a GML Model Using Sketch-based Interaction

2017

Darmstadt, TU, Master Thesis, 2017

This Master Thesis presents a novel technique to intuitively insert meta-parameters into a procedural GML model with the help of sketch-based interaction. A GML model consist of a sequence of procedural modeling commands, for example extrusions. These are called with a set of local offset values, which can be converted to global space and anchored in the surface mesh of the model. As the global positions do not necessarily lie on the mesh surface, this is done by finding reference vertices. The system uses a mesh deformation technique to deform the evaluated surface of the model and creates a progression of intermediate target meshes. During the deformation, the reference vertices provide the global offset positions, whose path can be approximated by a B-spline. By exchanging the initial values of the commands by this B-spline, a continuous parameter space of the meta-parameter is defined. The deformation process is supported by a mesh segmentation to create pre-defined deformation targets for the user. Using intuitive sketch-based methods, these can be easily adapted to the users needs. The results show that the system closely imitates the mesh deformation with the help of the modeling commands. Furthermore, the system was evaluated to be intuitive and easy to use.

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Manjunath, Nagarjun; Kraus, Dieter (Betreuer); Rus, Silvia (Betreuer)

Simulation and Validation of Capacitive Sensing on Flexible and Curved Surfaces Applied on Sleeping Breathing Rate Detection

2017

Bremen, Hochschule, Master Thesis, 2017

In recent years the capacitive sensing is the main technology, act as input in smart devices. There will be limitations for the flat surface, and nowadays people wants to use flexible surface input devices such as foldable mobiles, flexible input devices, and curved input devices. For these input devices, the surface wants to be flexible and curved; limited research has been carried out till now on curved and flexible surface capacitive sensing technology. The main objective of this master thesis is to investigate the capacitive sensing for different materials, different flexibility, and curvature. Simulation and validation of capacitive sensing on flexible and curved surfaces for various materials are carried out. Moreover, designing an own application (Breathing rate detection while sleeping) based on the characteristics obtained by capacitive sensing for various material on the flexible and curved surface.

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Single Image Marine Snow Removal based on a Supervised Median Filtering Scheme

2017

Imai, Francisco (Ed.) et al.: VISAPP 2017. Proceedings : 12th International Conference on Computer Vision Theory and Applications (VISIGRAPP 2017 Volume 4). SciTePress, 2017, pp. 280-287

International Conference on Computer Vision Theory and Applications (VISAPP) <12, 2017, Porto, Portugal>

Underwater image processing has attracted a lot of attention due to the special difficulties at capturing clean and high quality images in this medium. Blur, haze, low contrast and color cast are the main degradations. In an underwater image noise is mostly considered as an additive noise (e.g. sensor noise), although the visibility of underwater scenes is distorted by another source, termed marine snow. This signal disturbs image processing methods such as enhancement and segmentation. Therefore removing marine snow can improve image visibility while helping advanced image processing approaches such as background subtraction to yield better results. In this article, we propose a simple but effective filter to eliminate these particles from single underwater images. It consists of different steps which adapt the filter to fit the characteristics of marine snow the best. Our experimental results show the success of our algorithm at outperforming the existing approaches by effectively removing this phenomenon and preserving the edges as much as possible.

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Adams, Oliver; Bockholt, Ulrich; Hildebrand, Axel; Jonescheit, Leiv; Krzikalla, Roland; Olbrich, Manuel; Pankratz, Frieder; Pfützner, Sebastian; Roth, Matthias; Scheer, Fabian; Schwerdtfeger, Björn; Staack, Ingo; Wasenmüller, Oliver

Soll/Ist-Vergleich

2017

Schreiber, Werner (Ed.) et al.: Web-basierte Anwendungen Virtueller Techniken: Das ARVIDA-Projekt - Dienste-basierte Software-Architektur und Anwendungsszenarien für die Industrie. Berlin: Springer Vieweg, 2017, pp. 263-307

Das Ziel des Anwendungsszenarios ist eine präzise Digitalisierung und die Erforschung effizienter Verfahren zur Integration dieser Umgebungsdaten in Mixed Reality Anwendungen. Einsatzgebiete für die Erfassung großer Messvolumina liegen im Bereich der Fabrik-, Produktions- und Montageplanung, bei denen ein realistisches digitales Abbild der vorhandenen Arbeitsumgebung eine wichtige zusätzliche Informationsquelle darstellt. Für kleine Messvolumina liegen die Einsatzbereiche in der Produktabsicherung entlang des gesamten Produktlebenszyklus. Das Anwendungsszenario "Soll/Ist-Vergleich" zeigt das Potential der Referenzarchitektur, weil hier zahlreiche existierende Technologien und ARVIDA-Entwicklungsergebnisse unterschiedlicher Partner über die Referenzarchitektur integriert wurden. Das Teilprojekt betrachtet zum einen die Umfelderkennung und Umfelderfassung in kleinen und großen Messvolumina, zum anderen wurden projektionsbasierte AR-Lösungen realisiert, durch die Verfahren für den Soll/Ist-Abgleich realisiert werden konnten.

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Siegmund, Dirk; Hörr, Oliver; Chiesa, Laura; Gabler, Frank; Braun, Andreas; Kuijper, Arjan

Talis - A Design Study for a Wearable Device to Assist People with Depression

2017

Reisman, Sorel (Ed.) et al.: 2017 IEEE 41st Annual Computer Software and Applications Conference Workshops : COMPSACW. Los Alamitos, Calif.: IEEE Computer Society Conference Publishing Services (CPS), 2017, pp. 543-548

IEEE International COMPSAC Workshop on User Centered Design and Adaptive Systems (UCDAS) <4, 2017, Torino, Italy>

One of the major diseases affecting the global population, depression has a strong emotional impact on its sufferers. In this design study, "Talis" is presented as a wearable device which uses emotion recognition as an interface between patient and machine to support psychotherapeutic treatment. We combine two therapy methods, "Cognitive Behavioral Therapy" and "Well- Being Therapy", with interactive methods thought to increase their practical application potential. In this study, we draw on the results obtained in the area of "affective computing" for the use of emotions in empathic devices. The positive and negative phases experienced by the patient are identified through speech recognition and used for direct communication and later evaluation. After considering the design possibilities and suitable hardware, the future realization of such technology appears feasible. In order to design the wearable, user studies and technical experiments were carried out. The results of these suggest that the device could be beneficial for the treatment of patients with depression.

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Ternary Sparse Matrix Representation for Volumetric Mesh Subdivision and Processing on GPUs

2017

Computer Graphics Forum, Vol.36 (2017), 5, pp. 59-69

Eurographics Symposium on Geometry Processing (SGP) <15, 2017, London, UK>

In this paper, we present a novel volumetric mesh representation suited for parallel computing on modern GPU architectures. The data structure is based on a compact, ternary sparse matrix storage of boundary operators. Boundary operators correspond to the first-order top-down relations of k-faces to their (k-1)-face facets. The compact, ternary matrix storage format is based on compressed sparse row matrices with signed indices and allows for efficient parallel computation of indirect and bottomup relations. This representation is then used in the implementation of several parallel volumetric mesh algorithms including Laplacian smoothing and volumetric Catmull-Clark subdivision. We compare these algorithms with their counterparts based on OpenVolumeMesh and achieve speedups from 3x to 531x, for sufficiently large meshes, while reducing memory consumption by up to 36%.

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Gutbell, Ralf; Kühnel, Hannes; Kuijper, Arjan

Texturizing and Refinement of 3D City Models with Mobile Devices

2017

Blanc-Talon, Jacques (Ed.) et al.: Advanced Concepts for Intelligent Vision Systems : 18th International Conference, ACIVS 2017, Antwerp, Belgium, September 18-21, 2017, Proceedings. Springer International Publishing, 2017. (Lecture Notes in Computer Science (LNCS) 10617), pp. 313-324

International Conference on Advanced Concepts for Intelligent Vision Systems (ACIVS) <18, 2017, Antwerp, Belgium>

Building recognition from images and video streams of mobile devices to texturize and refine an existing 3D city model is an open challenge, since such models most often do not completely represent the actual buildings. We present ways to extract buildings from images enabling improvement of the existing model. The approach is based on edge detection on images to detect walls, pure use of sensor data by creating an overlay to the video stream with the 3D model renderer from current position by a server, and the use of structure from motion algorithms to create point clouds and recognize a building via the support of the device's sensors. We show that we are thus able to texturize and refine an existing 3D city model.

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Ulmer, Alex; Kohlhammer, Jörn; Shulman, Haya

Towards Enhancing the Visual Analysis of Interdomain Routing

2017

Linsen, Lars (Ed.) et al.: IVAPP 2017. Proceedings : 8th International Conference on Information Visualization Theory and Applications (VISIGRAPP 2017 Volume 3). SciTePress, 2017, pp. 209-216

International Conference on Information Visualization Theory and Applications (IVAPP) <8, 2017, Porto, Portugal>

Interdomain routing with Border Gateway Protocol (BGP) plays a critical role in the Internet, determining paths that packets must traverse from a source to a destination. Due to its importance BGP also has a long history of prefix hijack attacks, whereby attackers cause the traffic to take incorrect routes, enabling traffic hijack, monitoring and modification by the attackers. Proposals for securing the protocol are adopted slowly or erroneous. Our goal is to create a novel visual analytics approach that facilitates easy and timely detection of misconfigurations and vulnerabilities both in BGP and in the secure proposals for BGP. This work initiates the analysis of the problem, the target users and state of the art approaches. We provide a comprehensive overview of the BGP threats and describe incidents that happened over the past years. The paper introduces two new user groups beside the network administrators, which should also be addressed in future approaches. It also contributes a survey about visual analysis of interdomain routing with BGP and secure proposals for BGP. The visualization approaches are rated and we derive seven key challenges that arise when following our roadmap for an enhanced visual analysis of interdomain routing.

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Cibulski, Lena; Preim, Bernhard (Betreuer); May, Thorsten (Betreuer)

Towards Visual Feature Selection for Multivariate Time Series Data

2017

Magdeburg, Univ., Master Thesis, 2017

Time series analysis and modeling are essential tools for the transfer of knowledge across time, also called forecasting. This often involves the task of identifying the least number of features that are most useful for building a model that accurately forecasts a target without suffering from dimensionality issues. This is challenging, because time series involve many different characteristics that need to be captured by a model. Traditional wrapper approaches are bound to the actual learning algorithm that builds the model, which requires computational effort and limits their range of application. Filter methods are independent of the future model, but mostly take the form of a black box algorithm, which does not allow analysts to monitor and interactively guide the feature selection. In this thesis, the filter concept for multivariate time series is advanced by making use of the human perception and interpretation abilities for independent evaluation of a feature subset's quality. To ensure independence, we derive a quality criterion from a general assumption about the relationship between input and output in a valid model. An overview visualization enables analysts to visually assess its validity and to steer the analysis towards regions of interest, where the feature subset's quality is not sufficient. Critical regions can be analyzed in detail using the surrounding system of linked views. Findings contribute to an interactive refinement of the feature subset, which might also include the analyst's expertise. We evaluate the proposed method by applying it to real-world sensor data and an artificial time-oriented data set. The analyst was able to quickly distinguish well-explained regions from critical parts of the feature space, for which the identification of an additional explanatory feature could be tackled straight-away. Due to visualization constraints, the approach can handle only two-dimensional feature subsets, which are taken as input to perform one feature selection iteration. Still, it might be an inspiring step in the direction of universal dimension reduction that involves the human strengths.

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Damer, Naser; Rhaibani, Chadi Izzou; Braun, Andreas; Kuijper, Arjan

Trust the Biometric Mainstream: Multi-biometric Fusion and Score Coherence

2017

European Association for Speech, Signal and Image Processing (EURASIP): 2017 Proceedings of the 25th European Signal Processing Conference (EUSIPCO), pp. 2191-2195

European Signal Processing Conference (EUSIPCO) <25, 2017, Kos, Greece>

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 multi-biometric fusion, the scores of different biometric sources belonging to the comparison of interest are used to create the fused score. This is usually achieved by assigning static weights for the different biometric sources with more advanced solutions considering supplementary dynamic information like sample quality and neighbours distance ratio. This work proposes embedding score coherence information in the fusion process. This is based on our assumption that a minority of biometric sources, which points out towards a different decision than the majority, might have faulty conclusions and should be given relatively smaller role in the final decision. The evaluation was performed on the BioSecure multimodal biometric database with different levels of simulated noise. The proposed solution incorporates, and was compared to, three baseline static weighting approaches. The enhanced performance induced by including the coherence information within a dynamic weighting scheme in comparison to the baseline solution was shown by the reduction of the equal error rate by 45% to 85% over the different test scenarios and proved to maintain high performance when dealing with noisy data.

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Bernard, Jürgen; Zeppelzauer, Matthias; Sedlmair, Michael; Aigner, Wolfgang

A Unified Process for Visual-Interactive Labeling

2017

Sedlmaier, Michael (Ed.) et al.: EuroVA 2017 : EuroVis Workshop on Visual Analytics. Goslar: Eurographics Association, 2017, pp. 73-77

International EuroVis Workshop on Visual Analytics (EuroVA) <8, 2017, Barcelona, Spain>

Assigning labels to data instances is a prerequisite for many machine learning tasks. Similarly, labeling is applied in visualinteractive analysis approaches. However, the strategies for creating labels often differ in the two fields. In this paper, we study the process of labeling data instances with the user in the loop, from both the machine learning and visual-interactive perspective. Based on a review of differences and commonalities, we propose the 'Visual-Interactive Labeling' (VIAL) process, conflating the strengths of both. We describe the six major steps of the process and highlight their related challenges.

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Unifying Algebraic Solvers for Scaled Euclidean Registration from Point, Line and Plane Constraints

2017

Lai, Shang-Hong (Ed.) et al.: Computer Vision - ACCV 2016. Part V : 13th Asian Conference on Computer Vision, Taipei, Taiwan, November 20-24, 2016, Revised Selected Papers. Springer International Publishing, 2017. (Lecture Notes in Computer Science (LNCS) 10115), pp. 52-66

Asian Conference on Computer Vision (ACCV) <13, 2016, Taipei, Taiwan>

We investigate recent state-of-the-art algorithms for absolute pose problems (PnP and GPnP) and analyse their applicability to a more general type, namely the scaled Euclidean registration from pointto- point, point-to-line and point-to plane correspondences. Similar to previous formulations we first compress the original set of equations to a least squares error function that only depends on the non-linear rotation parameters and a small symmetric coefficient matrix of fixed size. Then, in a second step the rotation is solved with algorithms which are derived using methods from algebraic geometry such as the Gröbner basis method. In previous approaches the first compression step was usually tailored to a specific correspondence types and problem instances. Here, we propose a unified formulation based on a representation with orthogonal complements which allows to combine different types of constraints elegantly in one single framework. We show that with our unified formulation existing polynomial solvers can be interchangeably applied to problem instances other than those they were originally proposed for. It becomes possible to compare them on various registrations problems with respect to accuracy, numerical stability, and computational speed. Our compression procedure not only preserves linear complexity, it is even faster than previous formulations. For the second step we also derive an own algebraic equation solver, which can additionally handle the registration from 3D point-to-point correspondences, where other solvers surprisingly fail.

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Unsupervised 3D Object Retrieval with Parameter-Free Hierarchical Clustering

2017

Mao, Xiaoyang (Ed.) et al.: CGI 2017. Proceedings of the Computer Graphics International Conference. New York: ACM, 2017. (ACM International Conference Proceedings Series (ICPS) 1368), 6 p.

Computer Graphics International (CGI) <34, 2017, Yokohama, Japan>

In 3D object retrieval, additional knowledge like user input, classification information or database dependent configured parameters are rarely available in real scenarios. For example, meta data about 3D objects is seldom if the objects are not within a well-known evaluation database. We propose an algorithm which improves the performance of unsupervised 3D object retrieval without using any additional knowledge. For the computation of the distances in our system any descriptor can be chosen; we use the Panorama-descriptor. Our algorithm uses a precomputed parameter-free agglomerative hierarchical clustering and combines the information of the hierarchy of clusters with the individual distances to improve a single object query. Additionally, we propose an adaption algorithm for the cases that new objects are added frequently to the database. We evaluate our approach with 6 databases including a total of 13271 objects in 481 classes. We show that our algorithm improves the average precision in an unsupervised scenario without any parameter configuration.

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Wendland, Steve; Lukas, Uwe von

Unterwassertestfeld für maritime Robotik und Sensorik

2017

Hydrographische Nachrichten, (2017), 106, pp. 40-42

In der Ostsee vor der Hanse- und Hafenstadt Rostock soll für die Entwicklung neuer Technologien ein multifunktionales Unterwassertestfeld entstehen, auf dem neue Produkte und Verfahren meerestechnischer Komponenten bzw. komplexe Geräte und Systeme erprobt, kalibriert und demonstriert werden können. Konkrete Unterwasserstrukturen aus dem Alltag der Offshore-Industrie, wie Seekabel, Pipelines, Gründungsstrukturen, sollen in dem Testfeld eingebracht werden, um ein reales, möbliertes Areal von Offshore-Anwendungen zu schaffen. Ergänzend dazu soll im Rostocker Fischereihafen ein Innovationscampus als Landbasis mit umfassender Infrastruktur aufgebaut werden. Der geplante Innovationscampus ermöglicht zukünftig mit der Kombination aus Unterwassertestfeld und modernstem Gebäudekomplex den gesamten Prozess der Entwicklung und Erprobungen an einem Standort: von der Produktidee über die Laborprüfung bis hin zur realen Anwendungserprobung auf See.

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Using Hand Gestures to Interact with an Industrial Robot in a Cooperative Flexible Manufacturing Scenario

2017

Proceedings of the 3rd International Conference on Mechatronics and Robotics Engineering : ICMRE 2017. New York: ACM, 2017. (ACM International Conference Proceedings Series (ICPS) 01414), pp. 11-16

International Conference on Mechatronics and Robotics (ICMRE) <3, 2017, Paris, France>

Gesture recognition is a booming field of interest for many researchers. The Human-Machine Interaction developed from using wired devices such as the mouse and the keyboard till using touch screens and nowadays is evolving to the gesture interaction. Simultaneously, the machine or the industrial robot in particular is developing as well. The usual trend of using an industrial robot in a typical factory is to isolate it from the workers during the operation, due to the safety regulations. However, nowadays a new generation of a safe cooperative industrial robot exists. These robots are no longer dangerous to work around the humans. In a flexible manufacturing system, a cooperative scenario between the worker and the industrial robot can achieve the flexible manufacturing objectives. Therefore, during this research we propose and implement a holonic control system architecture which connects the industrial robot with the worker together in the same work environment in a flexible cooperative scenario. Moreover, we use the worker hand gestures to generate control events associated with the worker activities. Accordingly, the interaction between the worker and the industrial robot can be established.