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Lukas, Uwe von; Staack, Ingo; Köhler, Volker

3D-Technologie als Grundlage für die digitale Transformation der maritimen Wirtschaft

2016

Schiff & Hafen

Wie andere Industriezweige befindet sich auch die maritime Wirtschaft in einer Transformationsphase, die durch eine umfassende Digitalisierung der Prozesse ausgelöst wurde. Der Beitrag verdeutlicht in diesem Kontext das Potenzial der 3D-Technologie in unterschiedlichen Lebensphasen eines Schiffes und die Arbeit des Forums 3D maritim zur Kooperation von Unternehmen und Forschungseinrichtungen in diesem dynamischen Technologiefeld.

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3DHOG for Geometric Similarity Measurement and Retrieval on Digital Cultural Heritage Archives

2016

Intelligent Interactive Multimedia Systems and Services 2016

KES International Conference on Intelligent Interactive Multimedia Systems and Services (IIMSS) <9, 2016, Puerto de la Cruz, Tenerife, Spain>

Smart Innovation, Systems and Technologies
55

With projects such as CultLab3D, 3D Digital preservation of cultural heritage will become more affordable and with this, the number of 3D-models representing scanned artefacts will dramatically increase. However, once mass digitization is possible, the subsequent bottleneck to overcome is the annotation of cultural heritage artefacts with provenance data. Current annotation tools are mostly based on textual input, eventually being able to link an artefact to documents, pictures, videos and only some tools already support 3D models. Therefore, we envisage the need to aid curators by allowing for fast, web-based, semi-automatic, 3D-centered annotation of artefacts with metadata. In this paper we give an overview of various technologies we are currently developing to address this issue. On one hand we want to store 3D models with similarity descriptors which are applicable independently of different 3D model quality levels of the same artefact. The goal is to retrieve and suggest to the curator metadata of already annotated similar artefacts for a new artefact to be annotated, so he can eventually reuse and adapt it to the current case. In addition we describe our web-based, 3D-centered annotation tool with meta- and object repositories supporting various databases and ontologies such as CIDOC-CRM.

  • 978-3-319-39344-5
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Kiefer, Gundolf; Vahl, Matthias; Sarcher, Julian; Schäferling, Michael

A Configurable Architecture for the Generalized Hough Transform Applied to the Analysis of Huge Aerial Images and to Traffic Sign Detection

2016

2016 International Conference on Reconfigurable Computing and FPGAs

International Conference on Reconfigurable Computing and FPGAs (ReConFig) <2016, Cancun, Mexico>

Object recognition in huge image data sets or in live camera images at interactive frame rates is a very demanding task, especially within embedded systems. The recognition task includes the localization of a reference object and its rotation and scaling in a search image. The Generalized Hough Transform (GHT) is known as a powerful and robust technique to support this task by transforming the search image into a 4D parameter space. However, the GHT itself is very complex and demanding towards computational power and memory consumption. This paper presents a novel hardware architecture to perform a complete 4D GHT at interactive frame rates in an FPGA. The architecture is configurable in order to allow a trade-off between performance, accuracy and hardware usage. The proposed architecture has been implemented in a low-cost Zynq-7000 FPGA and successfully evaluated in two practical applications, namely groyne detection in aerial images and traffic sign detection.

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Seo, Byung-Kuk; Wuest, Harald

A Direct Method for Robust Model-Based 3D Object Tracking from a Monocular RGB Image

2016

Computer Vision - ECCV 2016 Workshops. Proceedings Part I

European Conference on Computer Vision (ECCV) <14, 2016, Amsterdam, The Netherlands>

This paper proposes a novel method for robust 3D object tracking from a monocular RGB image when an object model is available. The proposed method is based on direct image alignment between consecutive frames over a 3D target object. Unlike conventional direct methods that only rely on image intensity, we newly model intensity variations using the surface normal of the object under the Lambertian assumption. From the prediction about image intensity in this model, we also employ a constrained objective function, which significantly alleviates degradation of the tracking performance. In experiments, we evaluate our method using datasets that consist of test sequences under challenging conditions, and demonstrate its benefits compared to other methods.

  • 978-3-319-46603-3
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Thürck, Daniel; Wächter, Michael; Widmer, Sven; Bülow, Maximilian von; Seemann, Patrick; Pfetsch, Marc; Goesele, Michael

A Fast, Massively Parallel Solver for Large, Irregular Pairwise Markov Random Fields

2016

High Performance Graphics 2016

High-Performance Graphics (HPG) <8, 2016, Dublin, Ireland>

Given the increasing availability of high-resolution input data, today's computer vision problems tend to grow beyond what has been considered tractable in the past. This is especially true for Markov Random Fields (MRFs), which have expanded beyond millions of variables with thousands of labels. Such MRFs pose new challenges for inference, requiring massively parallel solvers that can cope with large-scale problems and support general, irregular input graphs. We propose a block coordinate descent based solver for large MRFs designed to exploit many-core hardware such as recent GPUs. We identify tree-shaped subgraphs as a block coordinate scheme for irregular topologies and optimize them efficiently using dynamic programming. The resulting solver supports arbitrary MRF topologies efficiently and can handle arbitrary, dense or sparse label sets as well as label cost functions. Together with two additional heuristics for further acceleration, our solver performs favorably even compared to modern specialized solvers in terms of speed and solution quality, especially when solving very large MRFs.

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Rohlwing, Stefan; Weber, Daniel [Betreuer]

A Finite-Volume Discretization for Structural Mechanical Problems in Static Equlibrium

2016

Wiesbaden, Hochschule RheinMain, Master Thesis, 2016

This thesis presents a novel and self-consistent finite volume method (FVM) for computational solid mechanics. Starting from a general dynamic approach, based on a balance of force in static equilibrium, we find a displacement based formulation using the general Hooke's law and the kinematic relationship in the form of the Cauchy strain tensor. Thus we provide an all-purpose method that allows to use isotropic, orthotropic and fully anisotropic material, no matter if it is homogeneous or inhomogeneous. This approach can be the basis of various discretization methods. Associated to the FVM used in fluid dynamics, we apply a cell centered method, approximate the integrals using the midpoint rule and use a difference scheme to arrange the cell-to-cell flux and find a linear system of equations. To disassemble the simulation domain, we pass up a complex mesher and use an equidistant and regular grid. Furthermore we implement a basic cut cell method to get a better approximation of the boundary of the domain. For a suitable description of mechanical structures it is required to work with tensors and vector fields. This is in contrast to problems in fluid dynamics, where the approach can be reduced to vectors and scalar fields. The corresponding changes and extensions are introduced and discussed.

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A Holonic Control System Design for a Human and Industrial Robot Cooperative Workcell

2016

2016 International Conference on Autonomous Robot Systems and Competitions

International Conference on Autonomous Robot Systems and Competitions (ICARSC) <2016, Braganca, Portugal>

As a result of the rapid development in industrial robot technology, a close safe cooperation with the human worker became quite possible. Accordingly an appropriate control system must exist to provide an intelligent tool for their information interaction. Therefore this paper is proposing a novel implementation model for a holonic control system solution. The ultimate goal of the proposed holonic control system is to adeptly manage the information exchange between an industrial robot in cooperation with a human worker in a production workcell. The novelty in the proposed holonic solution is that it merges the advantages of two well-known control architectures. The two architectures are IEC 61499 standard and autonomous reactive agent model. IEC 61499 has been used to implement the holon physical component, to handle the physical input/output (I/O) from/to an industrial robot or a human worker. Simultaneously autonomous reactive agent technology has been used to implement the holon communication component, to handle the information exchange between an industrial robot holon and a worker holon.

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Brodkorb, Felix; Kopp, Manuel; Kuijper, Arjan; Landesberger, Tatiana von

A Modular Rule-Based Visual Interactive Creation of Tree-Shaped Geo-Located Networks

2016

12th International Conference on Signal-Image Technology & Internet-Based Systems

International Conference on Signal Image Technology & Internet-Based Systems (SITIS) <12, 2016, Naples, Italy>

Geo-located networks are analyzed in various domains such as supply chain management. When simulating supply chain processes or when testing geo-visualization techniques, synthetic test datasets are needed. However, real world data are difficult to obtain and artificial data are cumbersome to create manually. In this paper, we present an interactive visual tree network generator that not only generates a network, but also attaches geo-locations to its nodes. We designed a modular rulebased system to control the generation process. A user can interactively use rules to parametrize the data generation process. The user can visually explore and adjust results intermediately after each generation iteration.

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A Novel Implementation Approach for Resource Holons in Reconfigurable Product Manufacturing Cell

2016

Proceedings of the 13th International Conference on Informatics in Control, Automation and Robotics

International Conference on Informatics in Control, Automation and Robotics (ICINCO) <13, 2016, Lisbon, Portugal>

Holonic Control Architecture is a successful solution model for reconfigurable manufacturing problems. Two well-known different technologies have been used separately to implement the holonic control model. The first technology is IEC 61499 standard, and the second is autonomous reactive agent. Both of the previous mentioned technologies have its own pros and cons. Therefore this research is merging the two technologies together in one solution body, to magnifying their pros and reduce their cons. Ultimately; it provides a novel implementation model for the manufacturing holons, to be followed in similar reconfigurable manufacturing problems. A human worker in cooperation with a safe industrial robot, has been selected as a case study of a reconfigurable manufacturing problem. The proposed holonic control solution has been applied to the case study, to evaluate the ability of the solution to satisfy the requirements of the case study. The results show the ability of the proposed control solution to provide a flexible physical and logical interaction framework, which can be scaled over more workers in cooperation with more industrial robots.

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Prinold, Joe A. I.; Mazzà, Claudia; Di Marco, Roberto; Hannah, Iain; Malattia, Clara; Magni-Manzoni, Silvia; Petrarca, Maurizio; Ronchetti, Anna B.; Tanturri De Horatio, Laura; van Dijkhuizen, Pieter E.H.; Wesarg, Stefan; Viceconti, Marco

A Patient-Specific Foot Model for the Estimate of Ankle Joint Forces in Patients with Juvenile Idiopathic Arthritis

2016

Annals of Biomedical Engineering

Juvenile idiopathic arthritis (JIA) is the leading cause of childhood disability from a musculoskeletal disorder. It generally affects large joints such as the knee and the ankle, often causing structural damage. Different factors contribute to the damage onset, including altered joint loading and other mechanical factors, associated with pain and inflammation. The prediction of patients' joint loading can hence be a valuable tool in understanding the disease mechanisms involved in structural damage progression. A number of lower-limb musculoskeletal models have been proposed to analyse the hip and knee joints, but juvenile models of the foot are still lacking. This paper presents a modelling pipeline that allows the creation of juvenile patient-specific models starting from lower limb kinematics and foot and ankle MRI data. This pipeline has been applied to data from three children with JIA and the importance of patient-specific parameters and modelling assumptions has been tested in a sensitivity analysis focused on the variation of the joint reaction forces. This analysis highlighted the criticality of patient-specific definition of the ankle joint axes and location of the Achilles tendon insertions. Patient-specific detection of the Tibialis Anterior, Tibialis Posterior, and Peroneus Longus origins and insertions were also shown to be important.

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Fauser, Johannes; Stenin, Igor; Kristin, J.; Klenzner, Thomas; Schipper, Jörg; Sakas, Georgios

A Software Tool for Planning and Evaluation of Non-Linear Trajectories for Minimally Invasive Lateral Skull Base Surgery

2016

Curac 2016

Jahrestagung der Deutschen Gesellschaft für Computer- und Roboter Assistierte Chirurgie (CURAC) <15, 2016, Bern, Schweiz>

The research project MUKNO II investigates the feasibility of non-linear access paths for minimally invasive lateral skull base surgery to optimize safety distance to risk structures and direction of insertion vectors. For this purpose a new surgical planning tool for manual as well as automatic nonholonomic path planning was developed. In ten 3D surface models of the temporal bone region trajectories to specific target points were manually created. The distance to critical structures and the curvature were evaluated along the course of these trajectories. First experiments with automatic nonholonomic planning showed the applicability of the implemented motion planner in the complex dense environment.

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Strecker, Bernhard Arthur; Matthies, Denys J.C. [Advisor]; Thaller, Manfred [Advisor]

A Wearable Facial Expression Control Interface to Accomplish Microinteractions in Mobile Scenarios

2016

Köln, Univ., Master Thesis, 2016

In our modern society, computing technology has become ubiquitous. Starting with the advent of smartphones, wearable computing has become ever more commonplace and pervasive in recent years. Interaction does no longer only happen in confined environments. Having access to computer interface anytime and anywhere necessitates new interaction styles to fully benefit from the manifold technological and interactional possibilities computers offer. Since hands and eyes of users on the move are likely to be busy with other activities, alternative interaction strategies are worthwhile to consider. The human face is very communicative and consistently used for human-to-human interaction, but close to never used for human-computer-interaction. In this thesis, facial expression recognition with unobtrusive sensing technology is investigated. An overview over the concepts of wearable computing, periphal computer interaction and microinteractions is given. Since bulky hardware such as cameras cannot be used in mobile contexts without attracting attention and distracting the user, alternative technologies have been tested. Focus was laid on thoroughly testing seven different earplugs with mounted electrodes. A newly developed gesture set of 25 facial gestures was tested in conjunction with capacitive sensing, electric field sensing, and electromyography sensing technology. Facial muscle movements lead to electric and mechanical changes, which can be sensed inside the ear-canal. Classification accuraries above 90% for 5 gestures were achieved with both industrial grade capacitive sensing technology and a self-developed electric field sensing board. The theory behind each of the sensing technologies is explained depth throughout this thesis.

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El Hakimi, Wissam; Fellner, Dieter W. [Referent]; Sakas, Georgios [Referent]; Schipper, Jörg [Referent]

Accurate 3D-Reconstruction and -Navigation for High-Precision Minimal-Invasive Interventions

2016

Darmstadt, TU, Diss., 2016

The current lateral skull base surgery is largely invasive since it requires wide exposure and direct visualization of anatomical landmarks to avoid damaging critical structures. A multi-port approach aiming to reduce such invasiveness has been recently investigated. Thereby three canals are drilled from the skull surface to the surgical region of interest: the first canal for the instrument, the second for the endoscope, and the third for material removal or an additional instrument. The transition to minimal invasive approaches in the lateral skull base surgery requires sub-millimeter accuracy and high outcome predictability, which results in high requirements for the image acquisition as well as for the navigation. Computed tomography (CT) is a non-invasive imaging technique allowing the visualization of the internal patient organs. Planning optimal drill channels based on patient-specific models requires high-accurate three-dimensional (3D) CT images. This thesis focuses on the reconstruction of high quality CT volumes. Therefore, two conventional imaging systems are investigated: spiral CT scanners and C-arm cone-beam CT (CBCT) systems. Spiral CT scanners acquire volumes with typically anisotropic resolution, i.e. the voxel spacing in the slice-selection-direction is larger than the in-the-plane spacing. A new super-resolution reconstruction approach is proposed to recover images with high isotropic resolution from two orthogonal low-resolution CT volumes. C-arm CBCT systems offers CT-like 3D imaging capabilities while being appropriate for interventional suites. A main drawback of these systems is the commonly encountered CT artifacts due to several limitations in the imaging system, such as the mechanical inaccuracies. This thesis contributes new methods to enhance the CBCT reconstruction quality by addressing two main reconstruction artifacts: the misalignment artifacts caused by mechanical inaccuracies, and the metal-artifacts caused by the presence of metal objects in the scanned region. CBCT scanners are appropriate for intra-operative image-guided navigation. For instance, they can be used to control the drill process based on intra-operatively acquired 2D fluoroscopic images. For a successful navigation, accurate estimate of C-arm pose relative to the patient anatomy and the associated surgical plan is required. A new algorithm has been developed to fulfill this task with high-precision. The performance of the introduced methods is demonstrated on simulated and real data.

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Adaptive Semantics Visualization

2016

Studies in Computational Intelligence
646

Zugl.: Darmstadt, TU, Diss., 2014

This book introduces a novel approach for intelligent visualizations that adapts the different visual variables and data processing to human's behavior and given tasks. Thereby a number of new algorithms and methods are introduced to satisfy the human need of information and knowledge and enable a usable and attractive way of information acquisition. Each method and algorithm is illustrated in a replicable way to enable the reproduction of the entire "SemaVis" system or parts of it. The introduced evaluation is scientifically well-designed and performed with more than enough participants to validate the benefits of the methods. Beside the introduced new approaches and algorithms, readers may find a sophisticated literature review in Information Visualization and Visual Analytics, Semantics and information extraction, and intelligent and adaptive systems. This book is based on an awarded and distinguished doctoral thesis in computer science.

  • 978-3-319-30815-9
  • 978-3-319-30816-6
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Adaptive UW Image Deblurring via Sparse Representation

2016

Eurographics 2016. Short Papers

Annual Conference of the European Association for Computer Graphics (Eurographics) <37, 2016, Lisbon, Portugal>

We present an adaptive underwater (UW) image deblurring algorithm based on sparse representation where a blur estimation is used to guide the algorithm for the best image reconstruction. The strong blur in this medium is caused by forward scatter and is challenging since it increases by camera scene distance. It is a common practice to use methods such as dark channel prior to estimate the depth map, and use this information to improve the image quality. However, we found it not successful in the case of blur since these methods are based on haze phenomenon. We propose a simple but effective algorithm via sparse representation which establishes a blur strength estimation and uses this information for adaptive deblurring. Extensive experiments manifest the effectiveness of our method in case of small but challenging blur changes.

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Luu, Thu Huong; Stork, André [1. Gutachter]; Mueller-Roemer, Johannes [2. Gutachter]

Adaptives und hybrides SLAM für handgeführte RGBD-Kameras

2016

Darmstadt, TU, Master Thesis, 2016

Mit der steigenden Beliebtheit von RGBD-Sensoren wurde viel Forschung im Bereich der Aufnahme und Rekonstruktion von dreidimensionalen Umgebungen mit Hilfe von solchen Sensoren betrieben. Für die Konstruktion muss das sogenannte Simultaneous Localization and Mapping (SLAM)-Problem gelöst werden. Die meisten RGBD-SLAM-Systeme verwenden hierbei den punktbasierten Iterative Closest Point (ICP)-Algorithmus. Auch wenn ICP ein gut untersuchter Algorithmus ist, so stößt er bei verrauschten Daten und besonders bei texturarmen Bereichen mit wenigen geometrischen Merkmalen, wie z.B. großen leeren Flächen, auf Probleme. Eine Option, diese Limitierung anzugehen, ist das zusätzliche Ausnutzen von Ebenen in der Szene, besonders da sie die häufigste Form in von Menschen erbauten Innenräumen und Außenanlagen sind. Taguchi et al. [TJRF13] veröffentlichte 2013 die erste globale Registrierungsmethode, in welcher Punkt-zu-Punkt- und Ebene-zu-Ebene-Korrespondenzen zu einem echtzeitfähigen SLAM-System vereint werden. Kurz darauf folgte die Publikation von Ataer-Cansizoglu et al. [ACTRG13], welche zusätzlich ein Bewegungsvorhersage-Modell ausnutzt, um Korrespondenzen zu bestimmen. Ein Nachteil dieser Verfahren ist die hohe Verarbeitungszeit eines Registrierungsschrittes. Dieser bewirkt, dass die Verfahren nicht in der Lage sind, interaktive Rekonstruktionen durchzuführen. Das Ziel dieser Arbeit ist die Implementierung eines SLAM-Algorithmus für handgeführte RGBDKameras, der sowohl Punkte, als auch Flächen zur Registrierung nutzt. Im Gegensatz zu bestehenden Verfahren wird in dieser Arbeit ein lokaler Registrierungsalgorithmus umgesetzt. Flächenmerkmale werden bevorzugt verwendet, da ihre Anzahl in Szenen signifikant geringer ist als die von Punkten. Das ermöglicht eine schnellere Korrespondenzsuche und Registrierung. Dem zugrundeliegenden RANSACbasierten Algorithmus reicht bereits eine minimale Anzahl an Korrespondenzen aus, um die Sensorpose zu bestimmen. Somit ist der Algorithmus in der Lage, die Registrierung auch in texturarmen Bereichen mit wenigen geometrischen Merkmalen durchzuführen, in denen Techniken, welche nur Punkte benutzen, scheitern. Des Weiteren ermöglicht der lokale Registrierungsansatz eine interaktive Nutzung, um dem Nutzer in Echtzeit Rückmeldung über den Registrierungsprozess zu geben. Zusätzlich implementierte Erweiterungen, welche die detektierten Flächeninformationen zur Geometriekorrektur ausnutzen, unterstützen den Registrierungsvorgang. Durchgeführte Experimente demonstrieren eine interaktive Rekonstruktion von Innenräumen mit einer handgeführten RGBD-Kamera, einer Kinect. Zudem weist das System im Gegensatz zu vergleichbaren hybriden Systemen eine sechsfach höhere Rekonstruktionsrate auf. Bei der Gegenüberstellung anhand eines Benchmark-Datensatzes für RGBD-Sensoren konnte des Weiteren in texturarmen Umgebungen eine Überlegenheit gegenüber punktbasierten Verfahren nachgewiesen werden.

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Heß, Martin; Keul, Frank; Goesele, Michael; Hamacher, Kay

Addressing Inaccuracies in BLOSUM Computation Improves Homology Search Performance

2016

BMC Bioinformatics

Background: BLOSUM matrices belong to the most commonly used substitution matrix series for protein homology search and sequence alignments since their publication in 1992. In 2008, Styczynski et al. discovered miscalculations in the clustering step of the matrix computation. Still, the RBLOSUM64 matrix based on the corrected BLOSUM code was reported to perform worse at a statistically significant level than the BLOSUM62. Here, we present a further correction of the (R)BLOSUM code and provide a thorough performance analysis of BLOSUM-, RBLOSUM- and the newly derived CorBLOSUM-type matrices. Thereby, we assess homology search performance of these matrix-types derived from three different BLOCKS databases on all versions of the ASTRAL20, ASTRAL40 and ASTRAL70 subsets resulting in 51 different benchmarks in total. Our analysis is focused on two of the most popular BLOSUM matrices-BLOSUM50 and BLOSUM62. Results: Our study shows that fixing small errors in the BLOSUM code results in substantially different substitution matrices with a beneficial influence on homology search performance when compared to the original matrices. The CorBLOSUM matrices introduced here performed at least as good as their BLOSUM counterparts in ~ 75 % of all test cases. On up-to-date ASTRAL databases BLOSUM matrices were even outperformed by CorBLOSUM matrices in more than 86 % of the times. In contrast to the study by Styczynski et al., the tested RBLOSUM matrices also outperformed the corresponding BLOSUM matrices in most of the cases. Comparing the CorBLOSUM with the RBLOSUM matrices revealed no general performance advantages for either on older ASTRAL releases. On up-to-date ASTRAL databases however CorBLOSUM matrices performed better than their RBLOSUM counterparts in ~ 74 % of the test cases. Conclusions: Our results imply that CorBLOSUM type matrices outperform the BLOSUM matrices on a statistically significant level in most of the cases, especially on up-to-date databases such as ASTRAL greater than/equal to 2.01. Additionally, CorBLOSUM matrices are closer to those originally intended by Henikoff and Henikoff on a conceptual level. Hence, we encourage the usage of CorBLOSUM over (R)BLOSUM matrices for the task of homology search.

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AGIS: Automated Tool Detection & Hand-Arm Vibration Estimation using an Unmodified Smartwatch

2016

iWOAR 2016

International Workshop on Sensor-based Activity Recognition (iWOAR) <3, 2016, Rostock, Germany>

Over the past three decades, it has been known that longlasting and intense hand-arm vibrations (HAV) can cause serious diseases, such as the Raynaud- / White Finger- Syndrome. In order to protect workers nowadays, the longterm use of tools such as a drill, grinder, rotary hammer etc. underlie strict legal regulations. However, users rarely comply with these regulations because it is quite hard to manually estimate vibration intensity throughout the day. Therefore, we propose a wearable system that automatically counts the daily HAV exposure doses due to the fact that we are able to determine the currently used tool. With the implementation of AGIS, we demonstrate the technical feasibility of using the integrated microphone and accelerometer from a commercial smartwatch. In contrast to prior works, our approach does not require a technical modification of the smartwatch nor an instrumentation of the environment or the tool. A pilot study shows our proofof- concept to be applicable in real workshop environments.

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Colter, Lena; Scheckenbach, Kathrin; Stenin, Igor; Wesarg, Stefan; Klenzner, Thomas; Schipper, Jörg; Jung, Florian

Akustikusneurinom-Segmentierung: Anwendung der Radial-Strahl-basierten 3D-Methodik

2016

GMS Current Posters in Otorhinolaryngology - Head and Neck Surgery

Einleitung: Akustikusneurinome sind benigne Tumore des N. vestibularis im Bereich des Kleinhirnbrückenwinkels oder des inneren Gehörgangs. Bei langsamem Wachstum ist neben der operativen Entfernung oder der Strahlentherapie eine "wait and scan"-Strategie unter regelmäßigen MRT-Kontrollen möglich. Objektivierbare Tumorvolumenbestimmungen können mittels zeitaufwendiger Segmentierungen durchgeführt werden. Durch eine Automatisierung des Segmentierungsvorganges wird diese Methode schnell, genau und objektiv einsetzbar. Methode: Die Radial-Strahl-basierte 3D-Segmentierung sendet ausgehend von einem manuell vorgegebenen Saatpunktes, Strahlen radial in alle Richtungen und erzeugt unter Einbeziehung von Bildinformation und lokalem Formwissen eine Segmentierung. Innerhalb weniger Sekunden werden die Achsen und das Volumen des Tumors angezeigt. Innerhalb eines Projektes wurde die Methode spezifisch für Akustikusneurinome entwickelt und an unserem Patientengut validiert. Es wurden Messungen bei manueller und automatisierter Segmentierung durch verschiedene Untersucher durchgeführt, um die Reliabilität, Geschwindigkeit und Alltagstauglichkeit der Methode zu evaluieren. Ergebnisse: Das Volumen von Akustikusneurinomen kann auch durch unterschiedliche Untersucher reproduzierbar mit hoher Genauigkeit innerhalb weniger Sekunden automatisiert und somit schneller als manuell segmentiert werden. Schlussfolgerung: Die automatisierte Radial-Strahl-basierte 3D-Segmentierung ist eine gut geeignete Methode zur objektiven Volumenbestimmung von Akustikusneurinomen. Sie mindert die Inter-Observer-Variabilität und reduziert den Zeitaufwand der Bildbeurteilung. Insofern hat diese Methode ein gutes Potential, um v.a. bei der "<.wait and scan"-Methode in den klinischen Alltag eingeführt zu werden.

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Ambient Assisted Living

2016

eHealth in Deutschland

Das Anwendungsfeld Ambient Assisted Living (AAL) beschreibt technische Systeme zur Unterstützung hilfsbedürftiger Personen im Alltag. In den vergangenen Jahren wurde in Deutschland und Europa viel in die Entwicklung und Erprobung von Technologien zur Unterstützung in der häuslichen Umgebung investiert, jedoch häufig ohne nachhaltige Effekte am Markt. Ein fehlender Aspekt war häufig die mangelnde Involvierung aller notwendigen Parteien. In diesem Kapitel werden die Potenziale assistiver Technologien beleuchtet, eine Studie zur Akzeptanz derartiger Technologien bei Senioren vorgestellt sowie ein Ausblick auf zukünftige Entwicklungen in diesem Bereich präsentiert.

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An Automatic Free Fluid Detection for Morrison´s-Pouch

2016

Clinical Image-Based Procedures. Translational Research in Medical Imaging

International Workshop on Clinical Image-based Procedures (CLIP) <5, 2016, Athens, Greece>

Ultrasound provides a useful and readily available imaging tool to detect free fluids in blunt abdominal trauma patients. However, applying conventional 2D ultrasound to diagnose the patient requires a well trained physician. In this paper we describe a fully automatic free fluid detection pipeline for the hepathorenal recess or Morrison's pouch using 3D ultrasound acquisitions. The image data is collected using the standardized "Focused Assessment with Sonography for Trauma" (FAST) exam. Our method extracts key structures like the kidney and the liver from the image data and uses their relative positions to search and detect free fluids between the organ interfaces. To evaluate our method we have developed a free fluid simulation that allows us to generate free fluid images using acquisitions of healthy volunteers. Our intentions are to enable even untrained ultrasound operators to perform a free fluid diagnosis of an injured person. In order to do this, our method additionally provides basic image acquisition guidance information.

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Krispel, Ulrich; Evers, Henrik Leander; Tamke, Martin; Ullrich, Torsten

An Automatic Hypothesis of Electrical Lines from Range Scans and Photographs

2016

ICCCBE2016

International Conference on Computing in Civil and Building Engineering (ICCCBE) <16, 2016, Osaka, Japan>

Building information modeling (BIM) with high level of detail and semantic information on buildings throughout their lifetime are getting more and more important for stakeholders in the building domain. Currently, such models are not yet present for the majority of today's building stock. With increasing speed and precision of laser scans or photogrammetry, geometric data can be acquired at reasonable costs. Unfortunately, these data are unstructured and do not provide high-level semantic information, which stakeholder require for non-trivial workflows. A current research topic are methods to extract non-visible structures from visible geometric entities. This work uses domain specific geometric and semantic constraints to automatically deduce information that is not directly observable in architectural objects: electrical power supply lines. It utilizes as-built BIM data from scans of indoor spaces in order to provide a hypothesis of paths of electrical lines. The system assumes that legal requirements and standards exist for defining the placement of power supply lines. This prior knowledge is formalized in a set of rules, using a 2D shape grammar that yields installation zones for a given room. Observable endpoints (sockets and switches) are detected in indoor scenes of buildings using methods from computer vision. The information from the reconstructed BIM model, as well as the detections and the generated installation zones are combined in a graph that represents all likely paths the power lines could take. Using this graph and a discrete optimization approach, the subgraph is generated that corresponds to a probable hypothesis. Our approach has been tested against synthetic and measured data and shows promising first results. Application possibilities include generation of a probable wiring for as-built / optically acquired building model, or suggesting cable ducts for a building reorganization or during planning of a new building.

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Schulz, Hans-Jörg; Angelini, Marco; Santucci, Giuseppe; Schumann, Heidrun

An Enhanced Visualization Process Model for Incremental Visualization

2016

IEEE Transactions on Visualization and Computer Graphics

With today's technical possibilities, a stable visualization scenario can no longer be assumed as a matter of course, as underlying data and targeted display setup are much more in flux than in traditional scenarios. Incremental visualization approaches are a means to address this challenge, as they permit the user to interact with, steer, and change the visualization at intermediate time points and not just after it has been completed. In this paper, we put forward a model for incremental visualizations that is based on the established Data State Reference Model, but extends it in ways to also represent partitioned data and visualization operators to facilitate intermediate visualization updates. In combination, partitioned data and operators can be used independently and in combination to strike tailored compromises between output quality, shown data quantity, and responsiveness-i.e., frame rates. We showcase the new expressive power of this model by discussing the opportunities and challenges of incremental visualization in general and its usage in a real world scenario in particular.

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Siegmund, Dirk; Fu, Biying; Samartzidis, Timotheos; Wainakh, Aidmar; Kuijper, Arjan; Braun, Andreas

Attack Detection in an Autonomous Entrance System using Optical Flow

2016

7th International Conference on Imaging for Crime Detection and Prevention

International Conference on Imaging for Crime Detection and Prevention (ICDP) <7, 2016, Madrid, Spain>

Unstaffed access control portals are becoming more common in high security areas. Existing systems require expensive hardware, or are sensitive to changing environmental conditions. We present a single camera system for a mantrap which is able to verify that only one individual is in the designated transit area. Our novel approach combines optical flow and machine-learning classification. A database was created that consists of images of attempted attacks and regular verification. The results show that our approach provides competitive results and outperforms detection rates in several attack scenarios.

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Fehling, Christian Dominic; Goertz, Lutz; Hagenhofer, Thomas; Müller, Andreas

Ausbildungsqualität 4.0 - ein Blick in die Zukunft am Beispiel des Projektes Social Augmented Learning

2016

Unternehmensstrategie Ausbildungsqualität

Die Transformation hin zu einer Industrie 4.0, getragen durch einen bereits im Mainstream wahrgenommenen, ausgesprochen technologischen Entwicklungsschub stellt zahlreiche Berufsfelder vor nicht zu unterschätzende Herausforderungen. Das Berufsfeld Medientechnologin bzw. Medientechnologe Druck, das in diesem Beitrag und bei den Arbeiten im Projekt "Social Augmented Learning" im Mittelpunkt steht, ist davon ebenso stark betroffen wie andere Berufsfelder mit vergleichsweise hohem Anteil an Routinetätigkeiten im Kontext von Automatisierung und der Arbeit an, mit und in Bezug zu Maschinen. Ziel des Projektes war und ist es, nicht nur die technische Infrastruktur für ein effektives und effizientes digitales Lernen mit mobilen Endgeräten und mit Augmented Reality zu ermöglichen, zu definieren und zu beschreiben, sondern zudem in eine kohärente Medienstrategie für Berufsschulen und Ausbildungsbetriebe zu überführen.

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Hiemenz, Benedikt; Kuijper, Arjan [1. Gutachten]; Krämer, Michel [Betreuer]

Authentication and Searchable Symmetric Encryption for Cloud-Based Storage of Geospatial Data

2016

Darmstadt, TU, Master Thesis, 2016

Many companies outsource their data and computations to the cloud to benefit from a worldwide data access and economic advantages such as a flexible storage management. Since cloud infrastructures are usually provided by third parties, companies must protect their private data before moving them. An example are geospatial data sets storing confidential information about urban areas. To secure these data, we present two security extensions for cloud-based geospatial data storages. First, we introduce an authentication process enabling applications to securely identify their users. We build our approach on token-based techniques but enhance them by essential features such as a revocation mechanism allowing administrators to block certain users at any time. Our extension requires minimal information on the server side and is suitable for distributed environments like a cloud infrastructure. Our main security extension allows users to encrypt their geospatial data and make them searchable at the same time. We develop a Searchable Symmetric Encryption protocol using an index to provide search features on encrypted data. Our approach is dynamic as we do not require an initialization phase and allow users to constantly add new data to the index or remove existing records. In the course of this thesis, we design multiple versions of our protocol differing in their level of security and performance respectively. All of them support boolean expressions as part of the query and geospatial-related search criteria such as bounding boxes. On the client side, our protocol facilitates multi-device support because we only expect cryptographic keys. Our findings indicate that both extensions are suitable for real-world applications in distributed systems but the search in encrypted data requires some more runtime than in plaintext data.

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Noll, Matthias; Nadolny, Anne; Wesarg, Stefan

Automated Kidney Detection for 3D Ultrasound Using Scan Line Searching

2016

Proceedings of SPIE

SPIE Medical Imaging Symposium <2016, San Diego, CA, USA>

Ultrasound (U/S) is a fast and non-expensive imaging modality that is used for the examination of various anatomical structures, e.g. the kidneys. One important task for automatic organ tracking or computer-aided diagnosis is the identification of the organ region. During this process the exact information about the transducer location and orientation is usually unavailable. This renders the implementation of such automatic methods exceedingly challenging. In this work we like to introduce a new automatic method for the detection of the kidney in 3D U/S images. This novel technique analyses the U/S image data along virtual scan lines. Here, characteristic texture changes when entering and leaving the symmetric tissue regions of the renal cortex are searched for. A subsequent feature accumulation along a second scan direction produces a 2D heat map of renal cortex candidates, from which the kidney location is extracted in two steps. First, the strongest candidate as well as its counterpart are extracted by heat map intensity ranking and renal cortex size analysis. This process exploits the heat map gap caused by the renal pelvis region. Substituting the renal pelvis detection with this combined cortex tissue feature increases the detection robustness. In contrast to model based methods that generate characteristic pattern matches, our method is simpler and therefore faster. An evaluation performed on 61 3D U/S data sets showed, that in 55 cases showing none or minor shadowing the kidney location could be correctly identified.

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Bartschat, Andreas; Kuijper, Arjan [Gutachter]

Automatic Classification of Cornea Tissues for Autofocus Algorithm

2016

Darmstadt, TU, Master Thesis, 2016

Corneal confocal microscopy (CCM) is a spreading technique for investigations of cellular structures in the human cornea. It is non-invasive and allows in vivo imaging of the different tissue layers in the cornea with high resolution. High expectations are currently placed on CCM, to allow rapid and detailed analysis of pathological alterations affecting the peripheral nerves that innervate the cornea, resulting not only in fast diagnosis, but also providing insights into the progress and severity of diseases like diabetes. For the fast and reliable imaging of the sub-basal nerve plexus (SNP), the layer with the highest density of nerves, the focus must be adapted to compensate anatomical layer irregularities and reversible folds. This thesis analyses classification methods of the anatomical tissues surrounding the SNP, to find reliable and fast classification models, suitable for online focus adaptations of the microscope to the layer of interest based on the predicted tissue type of the current image. The proposed methods are able to achieve accuracies of more than 92% with a runtime of less than 10 ms per image, evaluated on datasets of more than 8000 images as well as successfully applied in studies for the reconstruction of large field of view images of the SNP.

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Bartschat, Andreas; Toso, Lorenzo; Stegmaier, Johannes; Kuijper, Arjan; Mikut, Ralf; Köhler, Bernd; Allgeier, Stephan

Automatic Corneal Tissue Classification Using Bag-Of-Visual-Words Approaches

2016

Forum Bildverarbeitung 2016

Forum Bildverarbeitung <1, 2016, Karlsruhe, Deutschland>

Corneal confocal microscopy is a promising diagnostic method for peripheral neuropathy. It allows the recording of the sub-basal nerve plexus (SNP) and enables the morphological analysis of peripheral nerves. This work evaluates classification models for real-time evaluation of cornea images in order to find suitable methods for an automatic focus adaptation to the SNP. The analyzed Bag-of-Visual-Words method leads to models with an accuracy of 0.9, even on a small training dataset, and a runtime of 18 ms per image. Furthermore, the analysis of the support vector machine real-valued output shows high potential for the implementation of real-time focus optimization methods.

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Jung, Florian; Knapp, Oliver; Wesarg, Stefan

Automatic Segmentation of Structures in CT Head and Neck Images using a Coupled Shape Model

2016

MIDAS Journal

The common approach to do a fully automatic segmentation of multiple struc tures is an atlas or multi-atlas based solution. These already have proven to be suitable for the segmentation of structures in the head and neck area and provide very accurate segmentation results, but can struggle with challenging cases with unnatural postures, where the registration of the reference patient(s) is extremely difficult. Therefore, we propose an coupled shape model (CoSMo) algorithm for the segmentation relevant structures in parallel. The model adaptation to a test image is done with respect to the appearance of its items and the trained articulation space. Even on very challenging data sets with unnatural postures, which occur far more often than expected, the model adaptation algorithm succeeds. The approach is based on an articulated atlas cite{Steger2012a}, that is trained from a set of manually labeled training samples. Furthermore, we have combined the initial solution with statistical shape models cite{Kirschner2011} to represent structures with high shape variation. CoSMo is not tailored to specifc structures or regions. It can be trained from any set of given gold standard segmentations and makes it thereby very generic.

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Kutlucan, Osman; Kuijper, Arjan [Prüfer]; Kirchbuchner, Florian [Betreuer]

Barrierefreies Lagersystem zur Unterstützung von Menschen mit eingeschränkter visueller Wahrnehmungsfähigkeit

2016

Darmstadt, TU, Master Thesis, 2016

Im Mittelpunkt dieser Masterarbeit steht die Realisierung eines Lagersystems für Menschen mit eingeschränkter visueller Wahrnehmungsfähigkeit. Das in diesem Rahmen entwickelte Lagersystem verwendet Hand- und Gestenerkennung, Spracherkennung, Sprachsynthese und Sonifikation. Das Ziel des Systems ist es, sowohl eine pervasive Benutzerschnittstelle anzubieten, welche es blinden Benutzern ermöglicht, mit dem Lagerbereich auf eine natürliche Weise zu interagieren, und ein Lagersystem zu haben, welches mit geringem Aufwand konfiguriert werden kann. Daher werden in der Thesis in erster Linie verschiedene verwandte Ansätze und Konzepte betrachtet, woraufhin beschrieben wird, wie das vorgeschlagene Konzept der Thesis entwickelt wurde und warum dieses Konzept sich besser für blinde Benutzer eignet. Um dies zu analysieren, wird das vorgeschlagene System iterativ evaluiert. Im Rahmen der Evaluation wurden Verbesserungsvorschläge aufgenommen, und die Präzision und Effizienz der Implementierung gemessen. Die Ergebnisse der Evaluation dieser Thesis zeigen, dass das Konzept des vorgeschlagenen Systems angemessen ist und von blinden Benutzern gut aufgenommen wird, was z.B. durch einen Teilnehmer der Evaluation bei der Beurteilung eines Subworkflows des Systems mit folgenden Worten bestätigt wurde: "Die Interaktion fühlt sich so an, als wäre man nicht blind". Aber die Implementierung des Systems weist einige Probleme auf, welche sich vorwiegend in der Hand- und Gestenerkennung des Systems zeigen. Mit Behebung dieser Probleme könnte die User Experience einen höheren Grad erreichen, wodurch das System im alltäglichen Leben einsetzbar werden könnte.

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Benchmarking Sensors in Smart Environments - Method and Use Cases

2016

Journal of Ambient Intelligence and Smart Environments

Smart environment applications can be based on a large variety of different sensors that may support the same use case, but have specific advantages or disadvantages. Benchmarking can allow determining the most suitable sensor systems for a given application by calculating a single benchmarking score, based on weighted evaluation of features that are relevant in smart environments. This set of features has to represent the complexity of applications in smart environments. In this work we present a benchmarking model that can calculate a benchmarking score, based on nine selected features that cover aspects of performance, the environment and the pervasiveness of the application. Extensions are presented that normalize the benchmark-ing score if required and compensate central tendency bias, if necessary. We outline how this model is applied to capacitive proximity sensors that measure properties of conductive objects over a distance. The model is used to identify existing and find potential new application domains for this upcoming technology in smart environments.

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Brömme, Arslan [Ed.]; Busch, Christoph [Ed.]; Rathgeb, Christian [Ed.]; Uhl, Andreas [Ed.]

BIOSIG 2016

2016

Annual International Conference of the Biometrics Special Interest Group (BIOSIG) <15, 2016, Darmstadt, Germany>

GI-Edition - Lecture Notes in Informatics (LNI)
P-245
  • 978-3-88579-654-1
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Schinko, Christoph; Peer, Markus; Hammer, Daniel; Pirstinger, Matthias; Lex, Cornelia; Koglbauer, Ioana; Eichberger, Arno; Holzinger, Jürgen; Eggeling, Eva; Fellner, Dieter W.; Ullrich, Torsten

Building a Driving Simulator with Parallax Barrier Displays

2016

Proceedings of the 11th Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications. Volume 1

International Joint Conference on Computer Vision and Computer Graphics Theory and Applications (VISIGRAPP) <11, 2016, Rome, Italy>

In this paper, we present an optimized 3D stereoscopic display based on parallax barriers for a driving simulator. The overall purpose of the simulator is to enable user studies in a reproducible environment under controlled conditions to test and evaluate advanced driver assistance systems. Our contribution and the focus of this article is a visualization based on parallax barriers with (I) a-priori optimized barrier patterns and (II) an iterative calibration algorithm to further reduce visualization errors introduced by production inaccuracies. The result is an optimized 3D stereoscopic display perfectly integrated into its environment such that a single user in the simulator environment sees a stereoscopic image without having to wear specialized eye-wear.

  • 978-989-758-175-5
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c-Space: Time-evolving 3D Models (4D) from Heterogeneous Distributed Video Sources

2016

GCH 2016

Eurographics Workshop on Graphics and Cultural Heritage (GCH) <14, 2016, Genova, Italy>

We introduce c-Space, an approach to automated 4D reconstruction of dynamic real world scenes, represented as time-evolving 3D geometry streams, available to everyone. Our novel technique solves the problem of fusing all sources, asynchronously captured from multiple heterogeneous mobile devices around a dynamic scene at a real word location. To this end all captured input is broken down into a massive unordered frame set, sorting the frames along a common time axis, and finally discretizing the ordered frame set into a time-sequence of frame subsets, each subject to photogrammetric 3D reconstruction. The result is a time line of 3D models, each representing a snapshot of the scene evolution in 3D at a specific point in time. Just like a movie is a concatenation of time-discrete frames, representing the evolution of a scene in 2D, the 4D frames reconstructed by c-Space line up to form the captured and dynamically changing 3D geometry of an event over time, thus enabling the user to interact with it in the very same way as with a static 3D model. We do image analysis to automatically maximize the quality of results in the presence of challenging, heterogeneous and asynchronous input sources exhibiting a wide quality spectrum. In addition we show how this technique can be integrated as a 4D reconstruction web service module, available to mobile end-users.

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Sheldrick, Peter; Wuest, Harald [Betreuer]; Kuijper, Arjan [Prüfer]

CAD-Model Tracking using RGB-D Cameras

2016

Darmstadt, TU, Master Thesis, 2016

This thesis deals with the determination of the six DOF of an RGB-D camera relative to a known CAD-Model. Extracting features in image based tracking with no other input data reduces the achievable precision of tracking. This thesis presents methods that use the whole input frame from a depth camera - these are so called "dense'" methods. Methods such as ICP, that is used in KinectFusion, and depth image warping, which is used in DVO-SLAM, are compared for the task of CAD-Model tracking. Rendering is used for tracking and both GPU implementations such as OpenGL and CPU ray casting is used to track real depth data.

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Calibration of Shared Flat Refractive Stereo Systems

2016

Image Analysis and Recognition

International Conference on Image Analysis and Recognition (ICIAR) <13, 2016, Póvoa de Varzim, Portugal>

The calibration of underwater camera systems differs significantly from calibration in air due to the refraction of light. In this paper, we present a calibration approach for a shared flat refractive stereo system that is based on virtual object points. We propose a sampling strategy in combination with an efficiently solvable set of equations for the calibration of the refractive parameters. Due to the independence of calibration targets of known dimensions, the approach can be realized by using stereo correspondences alone.

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Braun, Andreas; Zander-Walz, Sebastian; Krepp, Stefan; Rus, Silvia; Wichert, Reiner; Kuijper, Arjan

CapTap - Combining Capacitive Gesture Recognition and Acoustic Touch Detection

2016

iWOAR 2016

International Workshop on Sensor-based Activity Recognition (iWOAR) <3, 2016, Rostock, Germany>

Capacitive sensing is a common technology for finger-controlled touch screens. The variety of proximity sensors extends the range, thus supporting mid-air gesture interaction and application below any non-conductive materials. However, this comes at the cost of limited resolution for touch detection. In this paper, we present CapTap, which uses capacitive proximity and acoustic sensing to create an interactive surface that combines mid-air and touch gestures, while being invisibly integrated into living room furniture. We introduce capacitive imaging, investigating the use of computer vision methods to track hand and arm positions and present several use cases for CapTap. In a user study we found that the system has average localization errors of 1.5cm at touch distance and 5cm at an elevation of 20cm above the table. The users found the system intuitive and interesting to use.

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

Clinical Image-Based Procedures. Translational Research in Medical Imaging

2016

International Workshop on Clinical Image-based Procedures (CLIP) <5, 2016, Athens, Greece>

Lecture Notes in Computer Science (LNCS)
9958
  • 978-3-319-46471-8
  • 978-3-319-46472-5
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Combining Low-level Features of Offline Questionnaires for Handwriting Identification

2016

Image Analysis and Recognition

International Conference on Image Analysis and Recognition (ICIAR) <13, 2016, Póvoa de Varzim, Portugal>

When using anonymous offline questionnaires for reviewing services or products it is often not guaranteed that a reviewer does this only once as intended. In this paper an applied combination of different features of handwritten characteristics and its fusion is presented to expose such manipulations. The presented approach covers the aspects of alignment normalization, segmentation, feature extraction, classification and fusion. Nine features from handwritten text, numbers and checkboxes are extracted and used to recognize handwriter duplicates. The proposed method has been tested on a novel database containing pages of handwritten text produced by 1,734 writers. Furthermore we show that the unified biometric decision using a weighted sum combination rule can significantly improve writer identification performance even on low level features.

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Landesberger, Tatiana von; Basgier, Dennis; Becker, Meike

Comparative Local Quality Assessment of 3D Medical Image Segmentations with Focus on Statistical Shape Model-based Algorithms

2016

IEEE Transactions on Visualization and Computer Graphics

The quality of automatic 3D medical segmentation algorithms needs to be assessed on test datasets comprising several 3D images (i.e., instances of an organ). The experts need to compare the segmentation quality across the dataset in order to detect systematic segmentation problems. However, such comparative evaluation is not supported well by current methods. We present a novel system for assessing and comparing segmentation quality in a dataset with multiple 3D images. The data is analyzed and visualized in several views. We detect and show regions with systematic segmentation quality characteristics. For this purpose, we extended a hierarchical clustering algorithm with a connectivity criterion. We combine quality values across the dataset for determining regions with characteristic segmentation quality across instances. Using our system, the experts can also identify 3D segmentations with extraordinary quality characteristics. While we focus on algorithms based on statistical shape models, our approach can also be applied to cases, where landmark correspondences among instances can be established. We applied our approach to three real datasets: liver, cochlea and facial nerve. The segmentation experts were able to identify organ regions with systematic segmentation characteristics as well as to detect outlier instances.

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

Computational Geometry in the Context of Building Information Modeling

2016

Energy and Buildings

Building energy analysis has gained attention in recent years, as awareness for energy efficiency is rising in order to reduce greenhouse gas emissions. At the same time, the building information modeling paradigm is aiming to develop comprehensive digital representations of building characteristics based on semantic 3D models. Most of the data required for energy performance calculation can be found in such models; however, extracting the relevant data is not a trivial problem. This article presents an algorithm to prepare input data for energy analysis based on building information models. The crucial aspect is geometric simplification according to semantic constraints: the building element geometries are reduced to a set of surfaces representing the thermal shell as well as the internal boundaries. These boundary parts are then associated with material layers and thermally relevant data. The presented approach, previously discussed at the International Academic Conference on Places and Technologies (Ladenhauf et al., 2014), significantly reduces the needed time for energy analysis.

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

Constructive Roofs from Solid Building Primitives

2016

Transactions on Computational Science XXVI

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

The creation of building models has high importance, due to the demand for detailed buildings in virtual worlds, games, movies and geo information systems. Due to the high complexity of such models, especially in the urban context, their creation is often very demanding in resources. Procedural methods have been introduced to lessen these costs, and allow to specify a building (or a class of buildings) by a higher level approach, and leave the geometry generation to the system. While these systems allow to specify buildings in immense detail, roofs still pose a problem. Fully automatic roof generation algorithms might not yield desired results (especially for reconstruction purposes), and complete manual specification can get very tedious due to complex geometric configurations. We present a new method for an abstract building specification, that allows to specify complex buildings from simpler parts with an emphasis on assisting the blending of roofs.

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Carboni, Nicola; Bruseker, G.; Guillem, Anais; Bellido Castaneda, D.; Coughenour, Chance; Domajnko, Matevz

Data Provenance in Photogrammetry Through Documentation Protocols

2016

ISPRS Congress Prague 2016, Proceedings of Commission III

International Society for Photogrammetry and Remote Sensing Congress (ISPRS) <23, 2016, Prague, Czech Republic>

Documenting the relevant aspects in digitisation processes such as photogrammetry in order to provide a robust provenance for their products continues to present a challenge. The creation of a product that can be re-used scientifically requires a framework for consistent, standardised documentation of the entire digitisation pipeline. This article provides an analysis of the problems inherent to such goals and presents a series of protocols to document the various steps of a photogrammetric workflow. We propose this pipeline, with descriptors to track all phases of digital product creation in order to assure data provenance and enable the validation of the operations from an analytic and production perspective. The approach aims to support adopters of the workflow to define procedures with a long term perspective. The conceptual schema we present is founded on an analysis of information and actor exchanges in the digitisation process. The metadata were defined through the synthesis of previous proposals in this area and were tested on a case study. We performed the digitisation of a set of cultural heritage artefacts from an Iron Age burial in Ilmendorf, Germany. The objects were captured and processed using different techniques, including a comparison of different imaging tools and algorithms. This augmented the complexity of the process allowing us to test the flexibility of the schema for documenting complex scenarios. Although we have only presented a photogrammetry digitisation scenario, we claim that our schema is easily applicable to a multitude of 3D documentation processes.

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Dataset on Underwater Change Detection

2016

OCEANS 2016 MTS/IEEE Monterey

MTS/IEEE Oceans Conference and Exhibition (OCEANS) <2016, Monterey, CA, USA>

The detection of moving objects in a scene is a well researched but depending on the concrete research still often a challenging computer vision task. Usually it is the first step in a whole pipeline and all following algorithms (tracking, classification etc.) are dependent on the accuracy of the detection. Hence, a good pixel-precise segmentation of the objects of interest is mandatory for many applications. However, the underwater environment has mostly been neglected so far and there exists no common dataset to evaluate different algorithms under the harsh underwater conditions and therefore a comprehensive evaluation is impossible. In this paper, we present an underwater change detection dataset consisting of five videos and hundreds of handsegmented groundtruth images as well as a survey of different underwater image enhancement techniques and their impact on segmentation algorithms.

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Maus, Michael; Kuijper, Arjan [Gutachter]; Ruppert, Tobias [Betreuer]; Lücke-Tieke, Hendrik [Betreuer]

Definition und Visualisierung von zoombaren 2D-Projektionen im Web

2016

Darmstadt, TU, Bachelor Thesis, 2016

Zielsetzung der Arbeit ist die Erforschung und Entwicklung eines web-basierten Visualisierungssystems zum Erstellen und Testen von zoombaren Projektionskarten. Die grundlegende Idee besteht darin einen multidimensionalen Datensatz mithilfe von Projektionsmethoden auf zwei Dimensionen zu projizieren, um sie auf einer 2D-Fläche darzustellen In Anlehnung an die Card, Mackinlay, Shneiderman Visualisierungspipeline ist ein Datenverarbeitungsmodell entwickelt worden. Für die Datenverarbeitung werden verschiedene Distanzmetriken, Dimensionsreduktionsverfahren, Zooming Ansätze sowie Darstellungskonzepte berücksichtigt. Die Besonderheiten sowie Überlegungen der jeweiligen Technologie werden diskutiert. Ein Zooming-Ansatz ermöglicht große Datenmengen auf einer begrenzten Fläche darzustellen. Um Zusammenhänge innerhalb der Daten besser zu visualisieren werden Darstellungskonzepte diskutiert. Die Datenpunkte werden als glyph-basierte Objekte oder mithilfe Colormaps, verschiedenen Formen und Größen dargestellt. Best-Practices über Colormaps werden diskutiert. Um große Datenmengen in Echtzeit darzustellen erfolgt eine Trennung von dem Generierungs- und Visualisierungsprozess. Bei der Generierung werden mithilfe einer tabellarischen Datei und gewählten Konfiguration rechenintensive Transformationsprozesse ausgeführt, um Kartenmaterial zu erzeugen. Ähnlich zu Google-Maps wird das erzeugte Kartenmaterial durch eine Visualisierung dargestellt. Managementkonzepte zur Verwaltung verschiedener Kartensets sowie deren Erzeugung und Darstellung werden präsentiert. Über eine Oberfläche kann der Benutzer Kartenmaterial erzeugen und visualisieren. Der Benutzer lädt eine tabellarische Datei ins System hoch und wählt zwischen verschiedenen Konfigurationsparametern. Anschließend werden diese Informationen verwendet um Kartenmaterial zu erzeugen. Das Kartenmaterial sowie verschiedene Interaktionsmöglichkeiten werden in der Visualisierungsoberfläche bereitgestellt. Anhand verschiedener Anwendungsbeispiele werden die Vorteile dieses Visualisierungssystems präsentiert.

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Kohlhammer, Jörn; Proff, Dirk U.; Wiener, Andreas

Der Markt für Visual Business Analytics

2016

Analytische Informationssysteme

Visualisierung wird im Bereich Business Intelligence (BI) und Business Analytics immer wichtiger. Heutige BI-Software, gerade im Bereich der Self-Service-BI, wird von den Anwendern ohne ein interaktives Benutzerinterface, das ihnen verschiedene Visualisierungsmöglichkeiten bietet, nicht mehr akzeptiert. Dennoch muss Unternehmen und Anwendern noch besser dargelegt werden, wie sie von solchen Visualisierungslösungen am Ende tatsächlich profitieren können. Dieser genaueren Betrachtung der Vorteile widmet sich der Bereich Visual Business Analytics (VBA), der drei Teilthemen umfasst: Information Design (ID), Visual Business Intelligence (VBI) und Visual Analytics (VA). Dieser Beitrag soll anhand illustrativer Beispiele in diese Teilthemen einführen.

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Weber, Manuel; Monroy Rodriguez, Rafael [Betreuer]

Design, Construction and Programming of an Automated Positioning Platform for the Calibration of Imaging Systems

2016

Darmstadt, TU, Bachelor Thesis, 2016

For the intrinsic and color calibration of large-scale photogrammetric 3D scanners no fully-automated process is yet available. This work intends to lay the foundations to address this issue. During the course of this work the development of a new positioning system from scratch is performed. The development is based on a set of specifications which are assessed first. This assessment is following a standardized process model used in product development. The final goal being the positioning of several calibration patterns differing in type and use. The patterns used are precisely printed and produced in high quality. By acquiring several images of these patterns, it is possible to calibrate the cameras used in photogrammetric 3D scanners. Shortcomings regarding the time-consumption and inaccurate results of the manual calibration process motivated the development of a partly automated process. It is the aim of this work to create a positioning system, controllable by a graphical user interface (GUI). The GUI needs to be programmed as part of this project and allows the user to directly control the platform with direct transformation, often referred to as forward kinematics. This enables the possibility of placing the end effector along the optical axes of the image sensors that have to be calibrated. The considered test-cases involve the execution of pre-defined joint configurations and trajectories. At the same time basic safety mechanisms for the detection and prevention of deviations and collisions are implemented. A primary focus is on the movement of the end effector which is also constructed as part of this work and is independent of the positioning of the end point. Turning, tilting and translating relative to the optical axis of the respective imaging system is achieved. This is done with the help of a delta kinematic. The constraints in manufacturing are taken into account during the iterative refining process of the connecting and bearing parts. Among others the emerging generative manufacturing process Fused Deposition Modeling is applied as a rapid prototyping process.

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Die digitale Revolution macht auch vor Kulturerbe nicht halt - Notwendigkeit von 3D-Technologien

2016

IT business

Um dem wachsenden Bedarf nach optimierten Scanverfahren in 3D im Kulturbereich zu entsprechen, entwickelt das Fraunhofer Institut für Graphische Datenverarbeitung IGD einen Ansatz zur 3D-Massendigitalisierung. Um Objektmengen effizient zu erfassen, wird die bisher zeit- und kostenintensive Datenakquise durch Automatisierung des Prozessablaufs beschleunigt. Zudem wird eine originalgetreue Wiedergabe in hoher Qualität angestrebt, die Geometrie, Textur und optische Materialeigenschaften berücksichtigt.

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Digitale Transformation im Kulturerbe

2016

Restauratoren Handbuch 2016/2017

Die digitale Durchdringung aller Lebensbereiche erfasst auch das Kulturerbe. Digitale Technologien verändern die Art und Weise, wie Archäologen, Restauratoren und Denkmalpfleger arbeiten, indem sie neue Wege der Zusammenarbeit, Befunddokumentation und Restaurierungspraxis ermöglichen.

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Kammeyer, Yasmina Maria; Gutbell, Ralf [Betreuer]

Distributed Rendering of Geodata Based on Feature Separation

2016

Darmstadt, Hochschule, Master Thesis, 2016

Rendering of geodata is a challenging tasks, because the needed data is distributed on multiple institutions. The 3D Portrayal Service (3DPS) is the first realization of a standard, that is addressing this problem and which provides a solution for a combined visualization of distributed data through the use of the getView definition. The objective of this thesis is to design a framework that enables server site rendering through the getView operation interface, which is provided by the 3DPS standard. Therefore, the development of the framework concept follows the 3DPS standard principles. The framework is tested through the implementation of a prototype, which proves its functionality by simulating a defined use case. It could be shown that the framework concept can be used to implement a prototype, which realizes the getView operation. The framework could provide a solution for a combined visualization of distributed data.

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DQV - Data Quality Visualization

2016

Nowadays, electronic nautical charts (ENCs) are common tools to support safe navigation at sea. An essential purpose of such charts is to provide information concerning measured depths of waters and their associated uncertainty, so that routes can be selected, which maintain under keel clearance. While the representation of depth information in ENCs according to S-52 is generally accepted, the visualization of associated uncertainties is not. A recent study confirmed, that the current representation of uncertainty is difficult to understand for mariners and thus is rarely used. As the the new S-101 ENC standard is in development, this study aims at proposing solutions for standardization, which can visualize uncertainty in a more suitable way. For doing so, a three step approach is applied. First, bathymetric data, associated uncertainties and mariners' tasks are analyzed. Thereafter, existing approaches for visualizing uncertainty are examined. Finally, based on a compiled list of requirements, proposals for visualizing uncertainty of bathymetric data in ENCs are provided. This includes recommendations concerning what aspects of uncertainty should be visualized, where they should be visualized and how they should be visualized.

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Roskosch, Philipp; Twellmeyer, James; Kuijper, Arjan

Dynamic Sampling for Visual Exploration of Large Dense-Dense Matrices

2016

Human Interface and the Management of Information: Information, Design and Interaction

International Conference on Human Interface and the Management of Information (HIMI) <2016, Toronto, ON, Canada>

We present a technique which allows visual exploration of large dense-occupied similarity matrices. It allows the comparison of several dimensions of a multivariate data set. For the visualization, the data are reduced by sampling. The access time to individual elements is an ever increasing problem with increasing matrix size. We examine various database management systems and compare the access times for different problem sizes. The visualization responds to user interaction and allows the focus to specific areas within the data. For this, the data is filtered according to user interests and the visualization is refined with subsamples of the filtered data. The context is preserved in this process. The focus allows the discovery of relationships that would otherwise remain hidden.

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Berkei, Sarah; Kuijper, Arjan [1. Gutachter]; Limper, Max [2. Gutachter]

Effiziente und Vollautomatische Grobausrichtung für den Soll-Ist-Abgleich zwischen CAD-Modellen und Scandaten

2016

Darmstadt, TU, Master Thesis, 2016

Diese Arbeit befasst sich mit der Entwicklung und anschließenden Evaluation eines globalen Registrierungsverfahren zum Soll-Ist-Abgleich zwischen Scandaten und einem CAD-Modell. Dabei liegt der Fokus auf einer effizienten Ausrichtung der Daten zueinander, die schneller als ein manuelles Vorgehen ist. Als Grundlage dient der "4-Point Congruent Sets" Algorithmus, der die Transformation zwischen zwei Punktwolken zueinander berechnet. Im Rahmen dieser Arbeit wird er mit einem klassischen, auf den Anwendungsfall der Arbeit angepassten, Ansatz "RANSAC-based DARCES" evaluiert. Darüber hinaus werden das "Largest Common Pointset" und die "Hausdorff-Distanz" als Bewertungskriterien verglichen, um eine möglichst effiziente und genaue Registrierung zu erreichen. Um das Ergebnis der globalen Registrierung zu bewerten, wird der "Iterative Closest Point" Algorithmus in die globale Registrierung integriert. Zu erkennen ist, dass 4PCS, vor allem auf strukturreichen Oberflächen, mit diesem Ansatz in durchschnittlich 5,5 Sekunden bis zu 74% zuverlässige Ergebnisse liefert. Auf strukturarmen Oberflächen kann mittels des "RANSAC-based DARCES" bis 82% valide Ergebnisse erzielt werden, wobei die Zeit für die Berechnung mit den verwendeten Testmodellen durchschnittlich unter 4 Sekunden lag.

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Chiesa, Laura; Hörr, Oliver; Siegmund, Dirk [Betreuer]

Emotional User Interface

2016

Darmstadt, Hochschule, Bachelor Thesis, 2016

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Leissner, Johanna; Fuhrmann, Constanze

En Allemagne: L'Alliance de recherche pour la préservation du patrimoine culturel

2016

Culture et Recherche

Créée afin de renforcer les synergies entre les différents organismes de recherche en Allemagne, cette Alliance favorise la conduite de projets de recherche sur les questions de restauration et de conservation, au niveau national et international. Elle se veut aussi l'ambassadrice de la protection du patrimoine culturel auprès du public.

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Abramovici, Michael [Hrsg.]; Herzog, Otthein [Hrsg.]; Encarnação, José L. [Projektgruppenleiter]; Stork, André [Projektgruppenleiter]

Engineering im Umfeld von Industrie 4.0

2016

acatech STUDIE

Engineering im Zusammenhang mit Industrie 4.0 stellt eine gänzlich neue Herausforderung mit einer Vielzahl offener Fragen für alle Phasen des Produktlebenszyklus dar. Vernetzte smarte Produkte und Services eröffnen grundlegend neue Potenziale für Innovationen und neue Geschäftsfelder. Im Rahmen intensiver Gespräche mit Vertreterinnen und Vertretern aus der Wirtschaft wurden einige dieser Fragen und Innovationspotenziale adressiert und bewertet.

  • 978-3-8316-4501-5
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Zeltser, Anton; Kuijper, Arjan [1. Gutachten]; Kähm, Olga [2. Gutachten]

Entwicklung und Evaluierung eines Systems zur bildbasierten Detektion von Fehlern in Stoffen

2016

Darmstadt, TU, Master Thesis, 2016

Die Algorithmen aus den Bereichen Bildverarbeitung, Computer Vision und Maschinelles Lernen finden in der heutigen Zeit immer häufiger ihre Anwendung bei den Industrieprozessen. In vielen Bereichen der Technik und Industrie sind diese Algorithmen ein wichtiger Bestandteil des Planungs- und Produktionsprozesses geworden. Insbesondere in dem Qualitätskontrollvorgang haben bildbasierte Verfahren eine größere Bedeutung. Diese Verfahren ermöglichen es, die Qualität der Produktion, entsprechend den Qualitätsanforderungen, automatisch und präzise zu überprüfen und mögliche Fehlerteile zu identifizieren. Im Mittelpunkt dieser Masterarbeit steht die Schritt-für-Schritt Entwicklung und Analyse eines Systems (in Form eines Algorithmus) zur bildbasierten Detektion von Fehlern in Materialien. Zur Kontrolle werden gebrauchte Stoffstücke mit folgenden Defekten verwendet: Löcher, Risse und Silikonflecke. Eine Besonderheit bei der Erkennung liegt darin, dass die Materialien im Bild so aussehen, als ob sie unabsichtlich auf einen Tisch geworfen worden sind. Die zu prüfenden Materialien können nicht als eine aufgespannte (2-D) Ebene beschrieben werden. Auf diese Art können vorhandene Textilien im Bild neben Defekten verschiedene Merkmale, wie zum Beispiel Falten oder innere und äußere Ränder, besitzen. Diese zusätzlichen Merkmale könnten irrelevante Informationen für die Suche nach Defekten beinhalten. Um die irrelevante Information zu reduzieren, wird vorgeschlagen, dass ein vorhandenes Bild in Ausschnitte aufgeteilt wird. Damit lässt sich jeder Ausschnitt meistens mit einem Merkmal beschreiben. Diese Bildausschnitte werden als Inputdata für das System genutzt. Ziel der Arbeit ist es, zum einen, mit Hilfe von Algorithmen des Maschinellen Lernens ein System für die Detektion des Defekts in Stoffen aufzubauen,und zum anderen, das System sollte auseinanderhalten, ob ein Stoffstück Verschleiß (Riss oder Loch) oder Silikon besitzt, oder, ob ein Stoffstück fehlerfrei mit Falten ist. Anhand der Ausschnitte wird eine Entscheidung über den Defekt im Bild getroffen. Diese Arbeit zeigt, wie die Algorithmen Local binary patterns in Verbindung mit dem Klassifikationsverfahren Support Vector Machine für die Detektion der Defekte in Stoffen verwendet werden.

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Cui, Jian; Kuijper, Arjan; Sourin, Alexei

Exploration of Natural Free-Hand Interaction for Shape Modeling Using Leap Motion Controller

2016

2016 International Conference on Cyberworlds

International Conference on Cyberworlds (CW) <2016, Chongqing, China>

In this paper, we propose a web-enabled shape modeling system with natural free-hand interaction, which can be easily learned by users while imposing least mental load on them. The deformation interface allows for performing various deformations, including stretching, compressing, squeezing, enlarging, twisting and tapering, on shapes interactively mimicking how they are done in real life. The manipulation interface allows an object to be directly grabbed and manipulated with either one or two hands, while also smoothly switching between them. Constrained methods are also provided for precise manipulation. An intuitive metaphor is designed to help the users to discover the interaction techniques by themselves without any manuals or instructions. A rendering pipeline, based on function-based extension of VRML/X3D, is designed with hidden complexity to support the proposed functionalities of the system. Hands motions are captured by Leap Motion controller. The user study proves the naturalness of the modeling system, and its easiness to be learned and remembered.

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Explorative Suche in zeitbasierten Primärdaten

2016

Ausgezeichnete Informatikdissertationen 2015

Die Ära des Big Data birgt gewaltige Potenziale für die datenzentrierte Forschung, denen Herausforderungen wie die Größe, die Qualität oder temporale Aspekte der Daten gegenüberstehen. Für die explorative Suche nach unerforschtem Wissen in komplexen Daten benötigen Domänenexperten effektive Analysetechniken und -systeme. Im Design dieser Systeme lassen sich die Kompetenzen von Data Scientists mit denen der Domänenexperten vereinen. Am Beispiel von zeitbasierten Primärdaten präsentiere ich in meiner Dissertation Konzepte, Richtlinien, Techniken und Systeme für die explorative Suche zur Unterstützung der datenzentrierten Forschung. Dabei verfolge ich in einem Visual-Analytics-Ansatz die strikte Kopplung von visuell-interaktiven Benutzerschnittstellen mit algorithmischen Modellen zur Datenanalyse. Beim Design von explorativen Suchsystemen ermögliche ich den Vergleich und die Auswahl von Modellen, unter Einbezug von Domänenexperten.

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Braun, Andreas; Alekseew, Michael; Kuijper, Arjan

Exploring Machine Learning Object Classification for Interactive Proximity Surfaces

2016

Distributed, Ambient, and Pervasive Interactions

International Conference on Distributed, Ambient and Pervasive Interactions (DAPI) <4, 2016, Toronto, Canada>

Capacitive proximity sensors are a variety of the sensing technology that drives most finger-controlled touch screens today. However, they work over a larger distance. As they are not disturbed by non-conductive materials, they can be used to track hands above arbitrary surfaces, creating flexible interactive surfaces. Since the resolution is lower compared to many other sensing technologies, it is necessary to use sophisticated data processing methods for object recognition and tracking. In this work we explore machine learning methods for the detection and tracking of hands above an interactive surface created with capacitive proximity sensors. We discuss suitable methods and present our implementation based on Random Decision Forests. The system has been evaluated on a prototype interactive surface - the CapTap. Using a Kinect-based hand tracking system, we collect training data and compare the results of the learning algorithm to actual data.

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Alm, Rebekka; Urban, Bodo

Facilitating Information Exchange in Assembly Assistance by Recommending Contextualized Annotations

2016

RS-BDA '16. Proceedings of the First Workshop on Recommender Systems and Big Data Analytics

Workshop on Recommender Systems and Big Data Analytics (RS-BDA) <1, 2016, Graz, Austria>

To maintain an equally high quality and efficiency in production processes despite the increased flexibility, information and knowledge are the company's strategically most important resources today. At the same time the intellectual re- sources are difficult to capture and manage, thus requiring intelligent assistance systems that support the individuals by providing suitable means for interacting with information. Therefore, it is of great importance to find an easy and fast way to record and store "new" information, as well as to provide a sensible mechanism to provide the information when needed. We propose to use annotations in combination with a formalized knowledge base that represents the work domain to enable an intuitive (semi-)automatic information contextualization. This pre-condition enables a context-based an- notation recommendation allowing for the annotations to be provided automatically for a better information communication. We propose a framework to integrate different factors to measure the relevance of an annotation according to a given situation and illustrate the results of our work using the example of an assembly assistance system.

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Schwenk, Karsten; Bockholt, Ulrich

Farbrealistisches Rendering

2016

Angewandte Virtuelle Techniken im Produktentstehungsprozess

Kap. 4 wendet sich den Themen Simulation und Rendering zu. Ziel ist es, Entscheidungen in zunehmendem Maße an virtuellen Modellen zu treffen. Dazu müssen sowohl die funktionellen Eigenschaften als auch die visuellen Eigenschaften virtueller Modelle und Darstellungen weiter verbessert werden. Schwerpunkte der Forschungsarbeiten sind die Simulation flexibler Bauteile sowie die Erstellung von echtzeitfähigen Menschmodellen. Zur Verbesserung der visuellen Darstellung werden multispektrales Rendering, Methoden zur Farbkalibrierung und Bild-in-Bild-Technologien zur Erhöhung der lokalen Auflösung der Bildschirmdarstellung betrachtet.

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Le Moan, Steven; Blahová, Jana; Urban, Philipp; Norberg, Ole

Five Dimensions for Spectral Color Management

2016

Journal of Imaging Science and Technology

We present a novel extended colour space for low- dimensional spectral colour management, coined LabAB. We discuss design goals and perform a comparison of sev- eral approaches to fuse the perceptual information engen- dered by several illuminants. Results indicate that, with only five dimensions, LabAB conveys significantly no less perceptual information on average than state-of-the-art rep- resentations such as the interim connection space LabPQR. We also demonstrate that LabAB can be used for spectral vector error diffusion.

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Ruth, Thomas; Audersch, Stefan; Lukas, Uwe von; Schriever, Gerd; Nuppenau, Volker; Appel, Frank; Kühn, Manfred

FlexMoT - A Flexible and Adaptable Environmental Monitoring Platform for Offshore Applications

2016

OCEANS 2016 MTS/IEEE Monterey

MTS/IEEE Oceans Conference and Exhibition (OCEANS) <2016, Monterey, CA, USA>

This paper describes design, development and results from at sea tests of the FlexMoT (Flexible Monitoring Tool) monitoring platform. The goal of the project was the development of a stable and compact sensor platform with integrated vertical water column profiling, integrating new and precise chemical and physical sensors. The developed system offers a cost-efficient, easy-to-use and fast deployable underwater environmental monitoring solution with a high temporal and depth resolution. It is intended for near-real time environmental monitoring of remote, impacted and sensitive marine environments and addresses primarily non-scientific users. This paper gives an overview of the overall approach of the FlexMoT system and the system integration (hardware, software, sensors). Some of the developed core components will also be described in detail, namely the universal carrier system, the vertical profiling mechanism with a head buoy, the low impedance buoyancy, the wireless power and data transfer unit, the long-term power battery supply and the residue-free recovery concept. Additionally, a short summary of the dedicated modular data management and visualization software system for near real-time monitoring and data analysis is given. Finally, the paper reports on the conducted tests.

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Lunge, Matthias; Frank, Carsten; Esser, Elke; Fietzek, Peer; Ruth, Thomas; Audersch, Stefan; Lukas, Uwe von; Nuppenau, Volker; Kühn, Manfred; Appel, Frank; Schriever, Gerd; Rudorf, Uwe; Flögel, Sascha; Pfannkuche, Olaf

FlexMoT - Flexible Umweltmonitoring-Plattform für Notfall- und Langzeiteinsätze im Offshore-Bereich

2016

Statustagung Maritime Technologien

Statustagung Maritime Technologien <2016, Berlin, Deutschland>

Zielsetzung für das 2013 gestartete Projekt FlexMoT war die Entwicklung eines flexiblen Monitoring-Tools als Langzeitmesssystem, sowie als Notfallsystem mit geringstem Rüstaufwand und schneller Datenverfügbarkeit. Zusätzlich sollte die Möglichkeit bestehen, temporär vertikal (profilierend) in der Wassersäule messen zu können, wozu Messungen mit einem Fahrstuhl-Float vorgesehen wurden. Das Monitoring-System soll schwerpunktmäßig im Bereich der Umweltüberwachung im Umgebungswasser von Offshore Öl- und Gasproduktionsplattformen und Offshore-Windanlagen, aber auch für andere Messaufgaben unter Wasser, für wissenschaftliche Dauermessungen sowie zur Gewässerüberwachung genutzt werden können. Ziel des Projektes war die Entwicklung eines Baukastensystems, welches in der Lage ist, mit Modulkomponenten unterschiedliche Einsätze und Anforderungen zu bewältigen. Die modulare Systemstruktur soll die Anbindung unterschiedlicher Sensoren und Messgeräte ermöglichen und findet sich nicht nur auf Seiten der Hardware sondern auch in der zu entwickelnden Software zum Management, Auswertung und Visualisierung der erfassten Daten wieder.

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From CAD to 3D Tracking - Enhancing & Scaling Model-Based Tracking for Industrial Appliances

2016

2016 IEEE International Symposium on Mixed and Augmented Reality

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <15, 2016, Merida, Mexico>

For Augmented Reality to succeed in industrial appliances, industries demand not only robust and reliable tracking techniques, but also a scalable and performant pipeline, that is easy-to-integrate within the existing data- and content environment and that enables vendors to create tracking solutions on their own. In our demo, we present recent advances of our model tracking pipeline and tracking technology, which on the one hand is easy use and easy to integrate, while on the other hand robust enough during difficult environmental conditions and which delivers high accuracy for the industrial domain. We showcase our results inside an AR-manual scenario.

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From Sensor to Situational Awareness

2016

OCEANS 2016 MTS/IEEE Monterey

MTS/IEEE Oceans Conference and Exhibition <2016, Monterey, CA, USA>

This paper describes the integrated FlexMoT data management and visualization software system for marine sensor data. Unlike most existing solutions this software platform is designed to be neither data-centric nor visualization-centric, but seamlessly integrating both, management and visualization of measurement data. Within the project FlexMoT (Flexible Monitoring Tool) a modular, easy-to-use and fast deployable environmental monitoring solution with a high temporal and depth resolution for underwater environments has been developed. This monitoring system was designed for the use in the underwater surrounding of offshore installations like oil rigs or gas production platforms and other critical and sensitive marine environments. It enables the exact measurement of concentration of dissolved gases such as methane in water and other environmental parameters that may be indicators of leakages. The FlexMoT software stack offers situational awareness and advanced decision support in environmental monitoring by organizing, preparing and presenting the gathered sensor data in a way that (1) operator personnel of offshore installations and marine researchers can draw the right conclusions and (2) appropriate actions can be initiated swiftly and well-informed. Similar to the modular hardware approach, the software uses a plugin approach to foster the simple reconfiguration to different use-cases. The designed visualization system utilizes human perception to transform lots of data quickly and intuitively into helpful information, to draw attention to critical events or striking data and support explorative data analysis with interactive displays. The implemented visualization solution combines recent webtechnologies and linked interactive 2D and 3D data presentations utilizing a direct-touch interaction metaphor. In this paper, we present the complete software stack of FlexMoT for data management, operational near real-time monitoring, visual data analytics of marine environmental data and visual forecast of gas leakage situations. It is proposed as a universal approach to improve visualization-based work with heterogeneous sensor data in environmental monitoring and marine research.

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Herz, Maximilian; Kuijper, Arjan [Prüfer]; Räsch, Sascha [Betreuer]

G-Buffer Compression for Remote Rendering Web Applications

2016

Darmstadt, TU, Master Thesis, 2016

As modern CAD applications need to render big scenes it is necessary to use client-server hybrid rendering to distribute work between two machines. This can reduce the needed bandwith and enhance the rendering performance. One way to implement hybrid rendering is to render the scene into G-Buffers, send them to the client and perform deferred shading there to render the final image. With this approach there is no need to send gigabytes of 3D model data over the network. In this master thesis, we will look into different methods to compress G-Buffer data. The G-Buffer is composed of three parts (object id's, depths, normals). We will analyze to which extend common image compression algorithms like JPEG will work on these parts. There are also methods specifically for compressing normal and depth data which we will look at. We will evaluate selected algorithms to further enhance the overall G-Buffer compression ratio. A server and client application have to be developed in order to evaluate the different compression methods. To ensure that the client runs on a broad range of devices the code will be implemented as a web application using HTML5, Java Script and WebGL. Thus, only methods can be used which enable for a fast decompression even on devices with low computing capabilities. The results of this thesis will be used inside the instant3Dhub system technology, which is developed by the VCST department.

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Catalano, Chiara Eva [Ed.]; Luca, Livio De [Ed.]; Falcidieno, Bianca [Event Co-Chair]; Fellner, Dieter W. [Event Co-Chair]

GCH 2016

2016

Eurographics Workshop on Graphics and Cultural Heritage (GCH) <14, 2016, Genova, Italy>

The 14th EUROGRAPHICS Workshop on Graphics and Cultural Heritage (GCH 2016) aims to foster an international dialogue between ICT experts and CH scientists to have a better understanding of the critical requirements for processing, managing, and delivering cultural information to a broader audience. The objective of the workshop is to present and showcase new developments within the overall process chain, from data acquisition, analysis and synthesis, 3D documentation, and data management, to new forms of interactive presentations and 3D printing solutions. Interdisciplinary approaches for analysis, classification and interpretation of cultural artefacts are particularly relevant to the event. The intention of GCH 2016 is also to establish a scientific forum for scientists and CH professionals to exchange and disseminate novel ideas and techniques in research, education and dissemination of Cultural Heritage, transfer them in practice, and trace future research and technological directions. Therefore, we seek original, innovative and previously unpublished contributions in the computer graphics area applied to digital cultural heritage, challenging the state of the art solutions and leveraging new ideas for future developments. Specific sessions will be devoted to reports on applications, experiences and projects in this domain. Contributions are solicited (but not limited to) in the following areas: - 2/3/4D data acquisition and processing in Cultural Heritage - Multispectral imaging and data fusion - Digital acquisition, representation and communication of intangible heritage - Material acquisition analysis - Heterogeneous data collection, integration and management - 3D printing of cultural assets - Shape analysis and interpretation - Similarity and search of digital artefacts - Visualization and Virtual Museums - Multi-modal and interactive environments and applications for Cultural Heritage - Spatial and mobile augmentation of physical collections with digital presentations - Semantic-aware representation of digital artefacts (metadata, classification schemes, annotation) - Digital libraries and archiving of 3D documents - Standards and documentation - Serious games in Cultural Heritage - Storytelling and design of heritage communications - Tools for education and training in Cultural Heritage - Experiences and projects in Computer Graphics and CH documentation, conservation and dissemination

  • 978-3-03868-011-6
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Müller, Martin; Kuijper, Arjan [1. Gutachten]; Landesberger, Tatiana von [2. Gutachten]; Ballweg, Kathrin [Betreuerin]

Guidance zur Exploration von Entitätsgraphen aus Textkollektionen für Datenjournalismus

2016

Darmstadt, TU, Bachelor Thesis, 2016

An der TU Darmstadt wird new/s/leak entwickelt, ein Tool welches Journalisten bei der Recherche in großen Dokumentenmengen( wie z.B. den Panama Papers oder den Cablegate-Dokumenten) unterstützt. Beziehungen zwischen Personen, Organisationen, Orten und anderen Dingen die in der Dokumentenmenge erwähnt sind, werden in einem riesigen Graphen erfasst, der teilweise mehr als 100 Millionen Kanten enthält. Der Graph enthält für Journalisten interessante Informationen, die Suche nach diesen Informationen im Graph gleicht jedoch der sprichwörtlichen Suche nach der Nadel im Heuhaufen. Die Visualisierung eines solch riesigen Graphen ist zudem äußerst schwierig. Zur Lösung dieser Probleme eignet sich - wie in der Arbeit gezeigt wird - Guidance. Ein Graph-Guidance-System berechnet für einen gegeben Fokusknoten einen lokalen Teilgraph, der nur einen kleinen Teilausschnitt mit interessanten Verbindungen des kompletten Graphen zeigt. Dieser Teilgraph ist übersichtlich und gut erfassbar. Benutzer können innerhalb des Teilgraphen einen neuen Fokus setzten, was wiederum zu einem neuen, veränderten Teilgraph führt. So kann der große Graph exploriert werden. In dieser Arbeit wurde ein in new/s/leak integriertes Graph-Guidance-System entwickelt welches Journalisten bei der Recherche in großen Dokumentenmengen unterstützt. Zunächst wurden Anforderungen an die Graph-Guidance formuliert und bestehende Graph-Guidance-Systeme analysiert. Da keiner der bestehenden Ansätze ad-hoc die Anforderungen erfüllt, wurde ein neues Graph-Guidance-System entwickelt. Dieses baut vor allem auf den Arbeiten von van Ham und Perer [18] sowie von Kochtchi et al. [12] auf. Die entwickelte Guidance berücksichtigt die verschiedenen Typen, die Knoten besitzen können und ermöglicht Journalisten diese zu gewichten, zudem können Guidance-Schritte auch rückgängig gemacht werden und wiederholt werden. Dies erleichert Journalisten die Arbeit mit dem Graph. Die Journalisten werden des Weiteren bei ihrer Entscheidungsfindung durch Detailformationen zu Knoten unterstützt. Es gibt auch eine sinnvolle Verknüpfung der Netzwerkebene mit der Dokumentenebene. Journalisten können problemlos zu einzelnen Dokumenten gelangen, die mit einem Knoten bzw. einer Kante assoziiert sind. Die Guidance arbeitet mit anderen new/s/leak-Komponenten zusammen. Das Guidance-System ermöglicht Journalisten dank der integrierten Features eine flexible Recherche in der Dokumentenmenge, die Benutzeroberfläche ist dennoch intuitiv und überfordert den Benutzer nicht. Die entwickelte Guidance wurde mit Hilfe von Fallstudien und einer Hands-on Session mit Journalisten evaluiert.

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Shao, Lin; Schleicher, Timo; Behrisch, Michael; Schreck, Tobias; Sipiran, Ivan; Keim, Daniel A.

Guiding the Exploration of Scatter Plot Data Using Motif-based Interest Measures

2016

Journal of Visual Languages & Computing

Finding interesting patterns in large scatter plot spaces is a challenging problem and becomes even more difficult with increasing number of dimensions. Previous approaches for exploring large scatter plot spaces like e.g., the well-known Scagnostics approach, mainly focus on ranking scatter plots based on their global properties. However, often local patterns contribute significantly to the interestingness of a scatter plot. We are proposing a novel approach for the automatic determination of interesting views in scatter plot spaces based on analysis of local scatter plot segments. Specifically, we automatically classify similar local scatter plot segments, which we call scatter plot motifs. Inspired by the well-known tf ×idf-approach from information retrieval, we compute local and global quality measures based on certain frequency properties of the local motifs. We show how we can use these to filter, rank and compare scatter plots and their incorporated motifs. We demonstrate the usefulness of our approach with synthetic and real-world data sets and showcase our corresponding data exploration tool that visualizes the distribution of local scatter plot motifs in relation to a large overall scatter plot space.

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Förster, Tim; Thum, Simon; Kuijper, Arjan

High Availability of Big-Geo-Data as a Platform as a Service

2016

HCI in Business, Government, and Organizations: eCommerce and Innovation

International Conference on Human-Computer Interaction in Business, Government and Organization (HCIBGO) <3, 2016, Toronto, ON, Canada>

There are ever-increasing challenges in the development of spatial data. The data increase rises continuously. The sharp rise in these information collections more and more data storage is required. Furthermore, should the systems have high availability and provide acceptable response time under load. The fulfillment of such requirement can be limited realized with a simple client / server system, since these do not scale well and act slowly in poor conditions. Therefore, more and more applications are deployed in the cloud as a service. This brings many benefits; inter alia, improving the availability and scalability of services. In this work the design decisions is demonstrated using an existing server system that are necessary for the realization of the product in the cloud. This product is then provided as a "Platform as a Service". Here points are as discussed persistence in distributed systems and cloud API design. This is then tested in a distributed system and compared against a simple client / server system. Also, a model is presented, thus the availability of the system is calculated.

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Puhl, Julian; Knuth, Martin; Kuijper, Arjan

Image-Based Post-processing for Realistic Real-Time Rendering of Scenes in the Presence of Fluid Simulations and Image-Based Lighting

2016

Advances in Visual Computing. 12th International Symposium, ISVC 2016

International Symposium on Visual Computing (ISVC) <12, 2016, Las Vegas, NV, USA>

For real-time fluid simulation currently two methods are available: grid-based simulation and particle-based simulation. They both approximate the simulation of a fluid and have in common that they do not directly generate a visually pleasant surface. Due to time constraints, the subsequent generation of the fluid surface may not consume much time. What is usually generated is an approximate surface, which consists of many individual mesh elements and has no optical properties of a fluid. The visualization of a fluid in image space may contain different detail densities depending on the distance between observer and the fluid. Therefore, filters need to be applied in order to smooth these details to a consistent surface. Many approaches use strong filters in this step, which results in a too smooth surface. To this surface then noise is added in order to give it a rough appearance. To avoid this ad-hoc approach we present a post-processing approach of the direct visualization of the simulation data via image processing applications by both smoothing filters and an image pyramid. Our presented approach based on an image pyramid provides access to various levels of detail. These are used as a controllable low pass filter. Thus, different amounts of smoothing can be selected depending on the distance to the viewer, granting a better surface reconstruction.

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Borrmann, Daniel; Kuijper, Arjan [1. Gutachter]; Franek, Andreas [2. Gutachter]

Incorporating the Unscented Transform in Rao-Blackwellised Visual-Inertial SLAM

2016

Darmstadt, TU, Master Thesis, 2016

Monocular visual-inertial simultaneous localisation and mapping (SLAM) systems use a single camera and inertial sensors to build a sparse map of an environment and to simultaneously estimate the camera's position. Applications can be found, for example, in the robotics domain or in virtual and augmented reality applications. Nowadays, monocular visual SLAM systems are capable of operating in real-time on different platforms. The application of Rao-Blackwellised filtering techniques in visual SLAM has further improved the real-time capability and maximum map size of these systems. In many implementations, extended Kalman filters (EKFs) are used to estimate the camera's pose and landmark positions. Since the required dynamic and measurement functions in a visual SLAM system are usually non-linear, EKF-based implementations need to linearise these functions, which leads to linearisation errors in the state estimate. In these cases, the unscented Kalman filter (UKF) proved to provide better results in many scenarios. In this thesis, the unscented transform (UT) is incorporated into a Rao-Blackwellised visual-inertial SLAM system. It shows how the camera state and landmark positions can be estimated in unscented Rao-Blackwellised filtering. To this end, an appropriate motion model, as well as an inverse depth parametrisation for the landmark estimation, are incorporated into the filter. The proposed filter is tested on a visual-inertial dataset in different setups. Results are given for the UKF-based Rao- Blackwellised filter and an equivalent EKF-based implementation, to enable comparison between the two approaches.

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Bieber, Gerald; Trimpop, John; Kaulbars, Uwe; Hofmann, Anton

Individuelle Bestimmung der Hand-Arm-Vibrationsdosis mit Smartwatches

2016

6. VDI Tagung Humanschwingungen 2016

VDI Tagung Humanschwingungen <6, 2016, Würzburg, Germany>

Langanhaltende und intensive Vibrationseinwirkungen auf das Hand-Arm-System können zu schwerwiegenden Erkrankungen führen. Die Abschätzung einer Gefährdung hinsichtlich der Hand-Arm-Vibration (HAV) wird unter Berücksichtigung der Expositionsdauer sowie der Vibrationsintensität durchgeführt. Die subjektive Erfassung oder der Einsatz von Messgeräten zur Bestimmung der Expositionsdauer ist kostenintensiv, stört den Arbeitsablauf oder kann aufgrund des hohen Aufwandes nur sehr sporadisch und selten durchgeführt werden. Bedingt durch die Miniaturisierung in der Elektronik sind nun kostengünstige Smartwatches auf dem Markt, die eine Vielzahl von integrierten Sensoren enthalten. Obwohl die Smartwatches über leistungsfähige Beschleunigungs-, Drehraten- sowie Akustiksensoren sowie eine effiziente Verarbeitungseinheit verfügen, ist es bisher unklar, ob diese Systeme tatsächlich zur Bewertung der Hand-Arm-Vibration (HAV) eingesetzt werden können. In einer Machbarkeitsstudie wurden unter Laborbedingungen und in Feldversuchen Beschleunigungs- und Mikrofondaten während der Ausführung von Arbeiten mit vibrierenden Arbeitsgeräten erfasst und analysiert. Dabei wurde untersucht, welche Verfahren zur Vibrationsmustererkennung geeignet und welche Erhebungsparameter auszuwählen sind. Durch eine Klassifizierung der Messdaten wurde auf die genutzten Arbeitsgeräte sowie die Expositionszeiträume geschlossen. Als Ergebnis der Untersuchung wurden die Möglichkeiten und Rahmenbedingungen für eine individuelle Bestimmung der HA-Vibrationsdosis mit Smartwatches bestimmt und bewertet.

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Adel, Omar; Urban, Bodo [Supervisor]; Sadik, Ahmed R. [Supervisor]

Industrial Robot as an Efficient Tool for the Worker in the Flexible Manufacturing Paradigm

2016

Rostock, Univ., Bachelor Thesis, 2016

Industrial robots are essential resources in most of nowadays factories and/or manufacturing facilities. The industrial robots have very strong influence to reshape the industrial production concepts. From the moment the industrial robot appeared in factories till nowadays, the trend of using the industrial robot on the shop floor as a replacement of the human being. Therefore the industrial robots involved in mass production paradigm. During the mass production processes the industrial robots are preforming many repetitive tasks which are time consuming and boring for the human being, such as in products assembly and material handling. However in other production approach such as lean or flexible manufacturing paradigm, involving an industrial robot issues an important question, which is how an industrial robot can flexibly adapt to the changes in the production requirements and needs. Consequently the mentioned trend of using the industrial robot as the worker replacement has dramatically evolved, instead a new concept has been risen. The concept is to use the industrial robot along with the worker in cooperative processes. The main aim of this concept is to get both the advantages of the human worker and the industrial robot in a close proximity cooperative work. In other words the new concept offers the industrial robot as a new tool for the workers over the shop floor. The lean manufacturing paradigm has been built upon the idea of eliminating or reducing the "muda" (Japanese for waste or any activity that consumes resources without adding value) in design, manufacturing, distribution, and customer service processes. To apply this concept in a workcell which combines the human worker with an industrial robot, the industrial robot must be able to understand and comprehend the dependencies between his tasks and the human worker tasks. Thus during this thesis we are looking for a theoretical method to organize the task dependencies between an industrial robot in cooperation with the human worker. Then we create our implemented solution which can integrate the industrial robot with the worker based on the tasks dependencies. Furthermore we compose a cooperation scenario, to be used later in testing and validating our conceptual solution on a real case study of industrial robot & worker cooperative workcell.

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Industrie 4.0: Cyber-physical Equivalence

2016

ProSTEP iViP Symposium 2016

ProSTEP iViP Symposium <2016, Stuttgart, Germany>

Our concept is called Cyber-physical Equivalence (CPE) and it contributes to the implementation of the Smart Factory.

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Information Visualization and Policy Modeling

2016

Big Data: Concepts, Methodologies, Tools, and Applications

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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Informationsvisualisierung und Visual Analytics

2016

Visualisierung von Managementberichten

Die Visualisierung von Geschäftsdaten und großen Datenmengen für die Entscheidungsfindung nimmt einen immer wichtigeren Stellenwert ein. Für die effektive Nutzung heutiger Tools ist ein Grundverständnis der Visualisierung nötig. Das Wissen über die menschliche Wahrnehmung erlaubt es, grundlegende Herangehensweisen zum Aufbau effektiver Visualisierungen zu formulieren und zu nutzen. Die richtige Informationsvisualisierung von Daten für die richtigen Nutzer und Aufgaben beschleunigt das Erkennen und Verstehen dieser Daten immens. Massive Datenmengen benötigen erweiterte Ansätze zur Integration von Visualisierung und automatischen Datenverarbeitung. Diese Ansätze bezeichnen wir als Visual Analytics. Der Prozess des User-Centered Design stellt sicher, dass der Nutzer während Planung und Entwicklung von Visualisierungen im Zentrum des Interesses steht. Der Beitrag gibt einen Überblick über Grundlagen der Visualisierung auch für große Datenmengen. Zudem hebt erdie wichtige Beachtung der Benutzer bei der Erstellung jeglicher Visualisierung hervor.

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Informationsvisualisierung und Visual Analytics

2016

Managementberichte gekonnt visualisieren

Die Visualisierung von Geschäftsdaten und großen Datenmengen für die Entscheidungsfindung nimmt einen immer wichtigeren Stellenwert ein. Für die effektive Nutzung heutiger Tools ist ein Grundverständnis der Visualisierung nötig. Das Wissen über die menschliche Wahrnehmung erlaubt es, grundlegende Herangehensweisen zum Aufbau effektiver Visualisierungen zu formulieren und zu nutzen. Die richtige Informationsvisualisierung von Daten für die richtigen Nutzer und Aufgaben beschleunigt das Erkennen und Verstehen dieser Daten immens. Massive Datenmengen benötigen erweiterte Ansätze zur Integration von Visualisierung und automatischen Datenverarbeitung. Diese Ansätze bezeichnen wir als Visual Analytics. Der Prozess des User-Centered Design stellt sicher, dass der Nutzer während Planung und Entwicklung von Visualisierungen im Zentrum des Interesses steht. Der Beitrag gibt einen Überblick über Grundlagen der Visualisierung auch für große Datenmengen. Zudem hebt er die wichtige Beachtung der Benutzer bei der Erstellung jeglicher Visualisierung hervor.

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Initialisierung des Trackings mit Hilfe von Machine-Learning-Verfahren

2016

Angewandte Virtuelle Techniken im Produktentstehungsprozess

Kap. 5 beschreibt die Forschungsthemen zum Schwerpunkt Tracking. Darunter ist das Erfassen der Position und Orientierung von Objekten bzw. des Anwenders im dreidimensionalen Raum zu verstehen. Die Arbeiten bilden damit die Grundlage für darauf aufbauende Funktionen wie beispielsweise die lagekorrekte Einblendung zusätzlicher Informationen oder die intuitive Interaktion durch Gesten. Neben Ansätzen zur Weiterentwicklung der Algorithmen des markerlosen Trackings werden ergänzende Sensoriken wie Wegaufnehmer an Robotern, Inertialsensoriken an Kameras betrachtet. Ein weiterer Ansatz untersucht die Hinzunahme von CAD-Daten zur Verbesserung des bildbasierten Trackings.

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Koa, Ming Di; Johan, Henry; Sourin, Alexei

Interactive Screenspace Stream-Compaction Fragment Rendering of Direct Illumination from Area Lights

2016

2016 International Conference on Cyberworlds

International Conference on Cyberworlds (CW) <2016, Chongqing, China>

Interactive rendering of illumination from area lights in virtual worlds has always proved to be challenging. In this paper, we extend the work of multi resolution rendering for direct illumination from area lights. We propose a deferred shading method for direct illumination which subdivides screenspace into multi resolution 2D-fragments in which higher resolution fragments are created to represent geometric and depth discontinuities as well as shadow boundaries. To detect shadow boundaries, our subdivision scheme, sub-fragment visibility test (SFVT), performs a visibility discontinuity check within each fragment and subdivides the fragment to a higher resolution level if discontinuity is found. In addition, our proposed gradient aware screenspace subdivision (GASS) algorithm accelerates the refinement by increasing the number of subdivisions based on gradient differences. Our technique utilizes the streamcompaction feature of the transform feedback shader (TFS) in the graphics shading pipeline to filter out fragments for soft shadow refinement. A single pass screenspace irradiance upsampling scheme which uses radial basis functions (RBF) is proposed for interpolating scattered fragments. This reduces artifacts caused by large fragments. Our technique does not require precomputations and is able to run at interactive rates.

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Paul, Stephan; Ruth, Thomas [Betreuer]; Lukas, Uwe von [1. Gutachter]

Interactive, Dynamic Segmentation of Spatio-Temporal, Multidimensional Marine Data

2016

Rostock, Univ., Bachelor Thesis, 2016

This thesis investigates methods to computationally segment marine sensor data in the domain of Oceanography. The segmentation supports the domain expert in visually analyzing water mass dynamics. Clustering techniques are used to aggregate specific types of sensor data. The resulting borders are visualized as an animation along the time axis. A plug-in-oriented architecture is presented to enable switching module-level implementations during live visualizations.

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Bergmann, Tim Alexander; Kuijper, Arjan [Betreuer]; Rojtberg, Pavel [Betreuer]

Interaktive Echtzeit-Kalibrierung

2016

Darmstadt, TU, Bachelor Thesis, 2016

Diese Arbeit beschäftigt sich mit der Entwicklung einer Heuristik, die unerfahrene Nutzer durch eine flexible Kamerakalibrierung leitet. Hierfür wird ein Qualitätsmaß basierend auf der Arbeit von Hartley und Zisserman [8, S. 138ff] hergeleitet. Dieses Qualitätsmaß wird verwendet, um Nutzern mit Hilfe von Vorschlägen für Kameraposen die Durchführung einer Kalibrierung zu vereinfachen. Durch diese Hilfestellungen gelingt es unerfahrenen Nutzern eine Kamera mit weniger Bildern, aber gleicher Qualität, bezogen auf den Reprojection Error, zu kalibrieren.

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

Interrelation between Gloss and Texture Perception of 2.5D Printed Surfaces

2016

Measuring, Modeling, and Reproducing Material Appearance 2016

Measuring, Modeling, and Reproducing Material Appearance (MMRMA) <2016, San Francisco, CA, USA>

The relation between perceived gloss levels and the texture height of a surface (sometimes referred to as bumpiness) has previously been investigated through several psychophysical experiments, which have suggested that a surface is perceived more glossy when the amount of texture is increased, and likewise, a surface is perceived more textured when the gloss level is increased. However, these studies have only been conducted using computer simulations as stimuli instead of physical surfaces or objects. The latter case is investigated in this paper, where physical samples of surfaces varying in surface gloss and texture levels were created by a 2.5D printing system. Psychophysical experiments were then conducted using these samples to investigate the influence of the macroscale texture characteristics on the perceived magnitude of surface glossiness. Although our results show that the influence of the gloss level on the perceived surface texture is negligible, they do confirm the existence of a slight influence of surface texture on the perception of surface glossiness.

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Breitfelder, Simon; Kuijper, Arjan [1. Gutachter]; Getto, Roman [2. Gutachter]

Invertierte GML-Modellierung durch Einpassen und Zusammensetzen von einfachen Strukturen

2016

Darmstadt, TU, Bachelor Thesis, 2016

In dieser Arbeit wird ein Verfahren zur invertierten Modellierung auf Basis von geometrischen Primitiven vorgestellt. Hierbei wird zunächst die Punktwolkenrepräsentation des Eingabemodells durch mehrere Primitive angenähert. Für die so erzeugten Primitive wird eine zusammenhängende Boundary Representation erzeugt, indem Verbindungsstücke eingefügt werden. Die endgültige Ausgabe des Algorithmus ist ein GML-Programm, welches diese Boundary Representation beschreibt.

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Investigating Low-Cost Wireless Occupancy Sensors for Beds

2016

Distributed, Ambient, and Pervasive Interactions

International Conference on Distributed, Ambient and Pervasive Interactions (DAPI) <4, 2016, Toronto, Canada>

Occupancy sensors are used in care applications to measure the presence of patients on beds or chairs. Sometimes it is necessary to swiftly alert help when patients try to get up, in order to prevent falls. Most systems on the market are based on pressure-mats that register changes in compression. This restricts their use to applications below soft materials. In this work we want to investigate two categories of occupancy sensors with the requirements of supporting wireless communication and a focus on low-cost of the systems. We chose capacitive proximity sensors and accelerometers that are placed below the furniture. We outline two prototype systems and methods that can be used to detect occupancy from the sensor data. Using object detection and activity recognition algorithms, we are able to distinguish the required states and communicate them to a remote system. The systems were evaluated in a study and reached a classification accuracy between 79 % and 96 % with ten users and two different beds.

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Riffnaller-Schiefer, Andreas; Augsdörfer, Ursula H.; Fellner, Dieter W.

Isogeometric Shell Analysis with NURBS Compatible Subdivision Surfaces

2016

Applied Mathematics and Computation

We present a discretisation of Kirchhoff-Love thin shells based on a subdivision algorithm that generalizes NURBS to arbitrary topology. The isogeometric framework combines the advantages of both subdivision and NURBS, enabling higher degree analysis on watertight meshes of arbitrary geometry, including conic sections. Because multiple knots are supported, it is possible to benefit from symmetries in the geometry for a more efficient subdivision based analysis. The use of the new subdivision algorithm is an improvement to the flexibility of current isogeometric analysis approaches and allows new use cases.

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Schröder, Max; Bader, Sebastian; Bieber, Gerald; Kirste, Thomas

IT-basiertes Aktivitätsmanagement in der Individualisierten Stationären Betreuung von Menschen mit Demenz

2016

Zukunft Lebensräume 2016

Zukunft Lebensräume <2016, Frankfurt/Main, Germany>

An einer Demenzerkrankung leiden in Deutschland derzeit etwa 1,5 Millionen Menschen, von denen viele in einer Pflegeeinrichtung versorgt werden müssen. Der vorliegende Beitrag beschreibt das Konzept eines IT-basierten Aktivitätsmanagement-Assistenten zur Betreuung dieser Menschen. Hierbei wird die aktuelle Situation objektiv mittels einer Smart-Watch und ihrer Sensoren erfasst. Basierend darauf können falls notwendig unterstützende Interventionsmaßnahmen ausgeqählt werden. Dadurch kann das Pflegepersonal von einigen ihrer Alltagsaufgaben entlastet und somit die Pflegetätigkeit effizienter werden.

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iWOAR 2016

2016

International Workshop on Sensor-based Activity Recognition (iWOAR) <3, 2016, Rostock, Germany>

ACM International Conference Proceedings Series
1183

Wearable sensors potentially enable for a better and unobtrusive recognition of human activity and the state of rest, sleep, stress and drive the ongoing trend of the quantified self-movement. As an enabling technology, powerful, while yet inexpensive MEMS-Chips (micro-electro-mechanical system) push the penetration of a broad variety of mobile devices. Thereby, these devices gain high interest, not only in terms of general customer products, but also as integrated systems in an industrial context, either way to enable continuous monitoring of complex life processes and workplace situations. Another challenge that research is facing concerns the limited human abilities of interaction in context of mobility and in situations, in which high attention is being demanded. New and alternative ways are needed to be found in order to take advantage of all human capabilities to enable safe and unobtrusive interaction. This conference-like workshop is initiated and organized by the Fraunhofer IGD in Rostock. It offers scientists, interested parties, and users in the area of sensor-based activity recognition and interaction the possibility to an exchange of experiences and a presentation of best-practice examples, as well as technical and scientific results. The workshop focuses on technologies for human activity recognition and interaction via inertial sensors (accelerometers, gyroscopes etc.) and their scientific applications.

  • 978-1-4503-4245-2
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Fellner, Dieter W. [Hrsg.]; Baier, Konrad [Red.]; Ackeren, Janine van [Red.]; Bornemann, Heidrun [Red.]; Wehner, Detlef [Red.]; Bumke, Carina [Gestaltung]; Boysens, Oliver [Gestaltung]; Egner, Juliane [Gestaltung]

Jahresbericht 2015

2016

Seit über 25 Jahren entwickelt das Fraunhofer IGD Technologien und Anwendungen auf Basis des Visual Computing. In Zusammenarbeit mit seinen Partnern entstehen technische Lösungen und marktrelevante Produkte. Das Fraunhofer IGD stellt dabei den Menschen als Benutzer in den Mittelpunkt und hilft ihm mit technischen Lösungen, das Arbeiten mit dem Computer zu erleichtern und effizienter zu gestalten. Die Lösungen des Instituts beschäftigen sich mit der ausgeprägten Fähigkeit des menschlichen Gehirns, komplexe Sachverhalte schnell visuell zu erfassen und zu verarbeiten. Durch seine zahlreichen Innovationen hebt das Fraunhofer IGD die Interaktion zwischen Mensch und Maschine auf eine neue Ebene. Der Mensch kann mithilfe des Computers und der Entwicklungen des Visual Computing ergebnisorientierter und effektiver arbeiten.

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JIT-Compilation for Interactive Scientific Visualization

2016

WSCG 2016. Short Papers Proceedings

International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision (WSCG) <24, 2016, Plzen, Czech Republic>

Due to the proliferation of mobile devices and cloud computing, remote simulation and visualization have become increasingly important. In order to reduce bandwidth and (de)serialization costs, and to improve mobile battery life, we examine the performance and bandwidth benefits of using an optimizing query compiler for remote postprocessing of interactive and in-situ simulations. We conduct a detailed analysis of streaming performance for interactive simulations. By evaluating pre-compiled expressions and only sending one calculated field instead of the raw simulation results, we reduce the amount of data transmitted over the network by up to 2/3 for our test cases. A CPU and a GPU version of the query compiler are implemented and evaluated. The latter is used to additionally reduce PCIe bus bandwidth costs and provides an improvement of over 70% relative to the CPU implementation when using a GPU-based simulation back-end.

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Hur, Junhwa; Roth, Stefan

Joint Optical Flow and Temporally Consistent Semantic Segmentation

2016

Computer Vision - ECCV 2016 Workshops

European Conference on Computer Vision (ECCV) <14, 2016, Amsterdam, The Netherlands>

The importance and demands of visual scene understanding have been steadily increasing along with the active development of autonomous systems. Consequently, there has been a large amount of research dedicated to semantic segmentation and dense motion estimation. In this paper, we propose a method for jointly estimating optical flow and temporally consistent semantic segmentation, which closely connects these two problem domains and leverages each other. Semantic segmentation provides information on plausible physical motion to its associated pixels, and accurate pixel-level temporal correspondences enhance the accuracy of semantic segmentation in the temporal domain. We demonstrate the benefits of our approach on the KITTI benchmark, where we observe performance gains for flow and segmentation. We achieve state-of-the-art optical flow results, and outperform all published algorithms by a large margin on challenging, but crucial dynamic objects.

  • 978-3-319-46603-3
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Schäfer, Marco; Krämer, Michel [Betreuer]

Konzeption und Realisierung einer Vertikalen Microservice Architektur für einen Online-Geodatenkatalog

2016

Campus Gießen, TH Mittelhessen, Master Thesis, 2016

Das Ziel der vorliegenden Arbeit ist der Entwurf einer Systemarchitektur sowie die Implementierung eines Prototypen für einen neuartigen Geodatenkatalog. Die Lösung soll das Suchen und Finden relevanter Daten für einen Benutzer möglichst einfach gestalten. Die Funktionsweise der Plattform soll ähnlich den bekannten Internet-Suchmaschinen sein, bei denen ein Suchfeld das zentrale Element zur Benutzerinterkation darstellt. Gefundene Ergebnisse sollen prominent nach einer bestimmten Rangfolge präsentiert werden. Um den hohen Anforderungen zu Benutzerinterkation und der somit benötigten geringen Antwortzeiten gerecht zu werden, soll ein reaktives Cloud-getriebenes System umgesetzt werden. Außerdem sollen neue Funktionalitäten schnell und mit geringem Aufwand zur Verfügung gestellt werden können, sowie sich nicht mehr benötigte Funktionalitäten entsprechend entfernen lassen. All diese Aktionen müssen während des laufenden Systembetriebes möglich sein, ohne das Gesamtsystem in irgendeiner Weise negativ zu beeinflussen. Hierzu wird, eine auf dem Microservice-Architekturstil basierende Systemarchitektur entworfen und mittels eines einfachen Prototyps technologisch wie architektonisch evaluiert. Zu Beginn des Projektes werden das durch die Plattform zu lösende Problem definiert sowie mögliche Nutzergruppen und Funktionalitäten festgelegt. Anhand dieser Informationen werden im Anschluss verschiedene Kriterien extrahiert, auf denen der darauffolgende Architekturentwurf basieren soll. Der Entwurf der Systemarchitektur gliedert sich in drei Phasen. In Phase eins werden Prinzipien für den Architekturentwurf, die weitere Implementierung sowie die Team- und Projektorganisation niedergeschrieben. In der zweiten Phase erfolgt ein Vorabentwurf der Architektur als monolithisches System. Dieses monolithische System dient dem Finden von Systemgrenzen anhand fachlicher Zusammengehörigkeiten, für das nachfolgende vertikale Zerlegen des Systems. Phase drei beschreibt den endgültigen Architekturentwurf. Im Anschluss daran werden die entworfene Architektur und die verwendeten Technologien durch die Implementierung verschiedener Funktionalitäten überprüft. Neben der Evaluation der eingesetzten Technologien und den Entwurf einer entsprechenden Systemarchitektur bildet die Arbeit eine Basis zur weiteren Implementierung der Plattform. Aufbauend auf der Implementierung erster, grundlegender Funktionalitäten sowie den entwickelten Konstruktionsrichtlinien können Entwickler schnell mit der Umsetzung der Plattform fortfahren.

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Braun, Andreas; Dutz, Tim

Low-cost Indoor Localization Using Cameras - Evaluating AmbiTrack and its Applications in Ambient Assisted Living

2016

Journal of Ambient Intelligence and Smart Environments

Many systems have been proposed in recent years that provide for the tracking and localization of users in indoor environments, often with a specific focus on pervasive computing settings. Our solution AmbiTrack, as presented here, allows for a marker-free localization and tracking of multiple persons, meaning that users are not required to carry special items or tags with them in order for the system to work. This approach allows for an application of AmbiTrack in circumstances where wearing a tag is not viable, e.g., in typical Ambient Assisted Living scenarios where the users of the provided technological systems are usually not technologically well-versed. In this contribution, we explain AmbiTrack and also introduce the adaptations we made for the 3rd EvAAL competition of 2013 in order to make the system more reliable in tracking multiple persons, using context information for improving the recognition rate, and for simplifying the set up and configuration process.

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Spiegelberg, Erik; Kuijper, Arjan [1. Gutachter]; Getto, Roman [2. Gutachter]

Maschinelles Lernen von parametrischen Modellen zur Klassifizierung von 3D Objekten

2016

Darmstadt, TU, Master Thesis, 2016

Das Ziel dieser Masterarbeit ist es, parametrische Modelle als Datenbasis für maschinelles Lernen zu untersuchen. Dabei wird untersucht wie gut diese Datenbasis zur Klassifikation von 3D Objekten geeignet ist. Als Ansatz für parametrische Modelle wird die Generative-Modelling-Language(GML) verwendet. Diese ermöglicht die Erstellung von parametrischen 3D Modellen. Zunächst wird damit eine Auswahl an Objekten Modelliert und eine Vielzahl von Exemplaren produziert. Zur Transformation der Modelle in lernbare Daten werden die 3D Objekt Deskriptoren PANORAMA und DESIRE verglichen. Als Methoden des maschinellen Lernens werden Varianten von k-Means, SVM und ein Nearest-Neighbor Ansatz Verwendung. Es werden verschiedene Szenarien erstellt, welche die Eignung von GML und PANORAMA für machinelle Lernansätze zeigen. Bei der Auswertung werden verschiedene Teile des PANORAMA Deskriptors auf ihre Klassifizierungseffizienz untersucht. Die Ergebnisse Zeigen das maschinelles Lernen anhand von parametrisch konzeptionierten Modellen zur Klassifikation von realen Objekten geeignet ist.

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Imai, Francisco H. [Conference Chair]; Segovia, Maria V. Ortiz [Conference Chair]; Urban, Philipp [Conference Chair]

Measuring, Modeling, and Reproducing Material Appearance 2016

2016

Measuring, Modeling, and Reproducing Material Appearance (MMRMA) <2016, San Francisco, CA, USA>

Electronic Imaging
9

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.

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Mesh Saliency Analysis via Local Curvature Entropy

2016

Eurographics 2016. Short Papers

Annual Conference of the European Association for Computer Graphics (Eurographics) <37, 2016, Lisbon, Portugal>

We present a novel approach for estimating mesh saliency. Our method is fast, flexible, and easy to implement. By applying the well-known concept of Shannon entropy to 3D mesh data, we obtain an efficient method to determine mesh saliency. Comparing our method to the most recent, state-of-the-art approach, we show that results of at least similar quality can be achieved within a fraction of the original computation time. We present saliency-guided mesh simplification as a possible application.

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Methods and a Research Agenda for the Evaluation of Event Sequence Visualization Techniques

2016

IEEE VIS 2016 Workshop on Temporal and Sequential Event Analysis

IEEE VIS 2016 Workshop on Temporal & Sequential Event Analysis <2016, Baltimore, USA>

The present paper asks how can visualization help data scientists make sense of event sequences, and makes three main contributions. The first is a research agenda, which we divide into methods for presentation, interaction & computation, and scale-up. Second, we introduce the concept of Event Maps to help with scale-up, and illustrate coarse-, medium- and fine-grained Event Maps with electronic health record (EHR) data for prostate cancer. Third, in an experiment we investigated participants' ability to judge the similarity of event sequences. Contrary to previous research into categorical data, color and shape were better than position for encoding event type. However, even with simple sequences (5 events of 3 types in the target sequence), participants only got 88% correct despite averaging 7.4 seconds to respond. This indicates that simple visualization techniques are not effective.

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Cui, Jian; Fellner, Dieter W.; Kuijper, Arjan; Sourin, Alexei

Mid-Air Gestures for Virtual Modeling with Leap Motion

2016

Distributed, Ambient, and Pervasive Interactions

International Conference on Distributed, Ambient and Pervasive Interactions (DAPI) <4, 2016, Toronto, Canada>

We study to which extent Leap Motion can be used for midair interaction while working on various virtual assembling and shape modeling tasks. First, we outline the conceptual design phase, which is done by studying and classification of how human hands are used for various creative tasks in real life. Then, during the phase of the functional design, we propose our hypothesis how to efficiently implement and use natural gestures with Leap Motion and introduce the ideas of the algorithms. Next we describe the implementation phase of the gestures in virtual environment. It is followed by the user study proving our concept.

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De Stefano, Antonio; Tausch, Reimar; Santos, Pedro; Kuijper, Arjan; Di Gironimo, Giuseppe; Fellner, Dieter W.; Siciliano, Bruno

Modeling a Virtual Robotic System for Automated 3D Digitization of Cultural Heritage Artifacts

2016

Journal of Cultural Heritage

Complete and detailed 3D-scanning of cultural heritage artifacts is a still time-consuming process that requires skilled operators. Automating the digitization process is necessary to deal with the growing amount of artifacts available. It poses a challenging task because of the uniqueness and variety in size, shape and texture of these artifacts. Scanning devices have usually a limited focus or measurement volume and thus require precise positioning. We propose a robotic system for automated photogrammetric 3D-reconstruction. It consists of a lightweight robotic arm with a mounted camera and a turntable for the artifact. In a virtual 3D-environment, all relevant parts of the system are modeled and monitored. Here, camera views in position and orientation can be planned with respect to the depth of field of the camera, the size of the object and preferred coverage density. Given a desired view, solving inverse kinematics allows for collision-free and stable optimization of joint configurations and turntable rotation. We adopt the closed-loop inverse kinematics (CLIK) algorithm to solve the inverse kinematics on the basis of a particular definition of the orientation error. The design and parameters of the solver are described involving the option to shift the weighting between different parts of the objective function, such as precision or mechanical stability. We then use these kinematic solutions to perform the actual scanning of real objects. We conduct several tests with different kinds of objects showing reliable and sufficient results in positioning and safety. We present a visual comparison involving the real robotic system with its virtual environment demonstrating how view poses for different-sized objects are successfully planned, achieved and used for 3D-reconstruction.

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Jun, Luo; Wang, Zhiqian; Shen, Chengwu; Kuijper, Arjan; Zhuoman, Wen; Liu, Shaojin

Modeling and Implementation of Multi-Position Non-Continuous Rotation Gyroscope North Finder

2016

Sensors

Even when the Global Positioning System (GPS) signal is blocked, a rate gyroscope (gyro) north finder is capable of providing the required azimuth reference information to a certain extent. In order to measure the azimuth between the observer and the north direction very accurately, we propose a multi-position non-continuous rotation gyro north finding scheme. Our new generalized mathematical model analyzes the elements that affect the azimuth measurement precision and can thus provide high precision azimuth reference information. Based on the gyro's principle of detecting a projection of the earth rotation rate on its sensitive axis and the proposed north finding scheme, we are able to deduct an accurate mathematical model of the gyro outputs against azimuth with the gyro and shaft misalignments. Combining the gyro outputs model and the theory of propagation of uncertainty, some approaches to optimize north finding are provided, including reducing the gyro bias error, constraining the gyro random error, increasing the number of rotation points, improving rotation angle measurement precision, decreasing the gyro and the shaft misalignment angles. According them, a north finder setup is built and the azimuth uncertainty of 18" is obtained. This paper provides systematic theory for analyzing the details of the gyro north finder scheme from simulation to implementation. The proposed theory can guide both applied researchers in academia and advanced practitioners in industry for designing high precision robust north finder based on different types of rate gyroscopes.

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Money Handling Training - Applications for Persons with Down Syndrome

2016

The 12th International Conference on Intelligent Environments

International Conference on Intelligent Environments (IE) <12, 2016, London, United Kingdom>

Paying for goods and services is a fundamental activity of daily living. Persons with Down Syndrome face these situations as a challenge. Through the usage of assistive technologies, the project Poseidon aims to enable persons with Down Syndrome to be more independent. In this paper we describe a training application for handling money. The novelty is the concept of extending the screen of an application to a palpable table, which serves as novel interaction device. Furthermore, we design the user interface highly personalizable in order to cover a large range of learning profiles of persons with Down Syndrome.

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Damer, Naser; Maul, Fabian

Multi-biometric Continuous Authentication: a Trust Model for an Asynchronous System

2016

FUSION 2016

International Conference on Information Fusion (FUSION) <19, 2016, Heidelberg, Deutschland>

Biometric technologies are used to grant specific users access to services and data. The access control is usually performed at the start of a session that spans over a period of time. Continuous authentication aims at insuring the identity of the user over this period of time, and not only at its start. Multi-biometrics aims at increasing the accuracy, robustness and usability of biometrics systems. This work presents a multibiometric continuous authentication solution that includes information from the face images and the keystroke dynamics of the user. A database representing a realistic scenario was collected to develop and evaluate the presented solution. A multi-biometric trust model was designed to cope with the asynchronous nature induced by the different biometric characteristics. A set of performance metrics are discussed and a comparison is presented between the performances of the single characteristic solutions and the fused solution.

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Multi-Camera Piecewise Planar Object Tracking with Mutual Information

2016

Journal of Mathematical Imaging and Vision

Real-time and robust tracking of 3D objects based on a 3D model with multiple cameras is still an unsolved problem albeit relevant in many practical and industrial applications. Major problems are caused by appearance changes of the object. We present 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 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 the mutual information as registration function combined with an inverse composition approach for reducing the computational costs and get a near-real-time algorithm. We discuss different hypotheses that can be made for the optimization algorithm.

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Sourina, Olga; Liu, Yisi; Hou, Xiyuan; Lim, Wei Lun; Müller-Wittig, Wolfgang K.; Wang, Lipo; Konovessis, Dimitrios; Chen, Chun-Hsien; Ang, Wei Tech

Neuroscience Based Design: Fundamentals and Applications

2016

2016 International Conference on Cyberworlds

International Conference on Cyberworlds (CW) <2016, Chongqing, China>

Neuroscience-based or neuroscience-informed design is a new application area of Brain-Computer Interaction (BCI). It takes its roots in study of human well-being in architecture, human factors study in engineering and manufacturing including neuroergonomics. In traditional human factors studies and/or well-being study, mental workload, stress, and emotion are obtained through questionnaires that are administered upon completion of some task and/or the whole experiment. Recent advances in BCI research allow for using Electroencephalogram (EEG) based brain state recognition algorithms to assess the interaction between brain and human performance. We propose and develop an EEG-based system CogniMeter to monitor and analyze human factors measurements of newly designed software/hardware systems and/or working places. Machine learning techniques are applied to the EEG data to recognize levels of mental workload, stress and emotions during each task. The EEG is used as a tool to monitor and record the brain states of subjects during human factors study experiments. We describe two applications of CogniMeter system: human performance assessment in maritime simulator and EEG-based human factors evaluation in Air Traffic Control (ATC) workplace. By utilizing the proposed EEG-based system, true understanding of subjects working patterns can be obtained. Based on the analyses of the objective real time EEG-based data together with the subjective feedback from the subjects, we are able to reliably evaluate current systems/hardware and/or working place design and refine new concepts and design of future systems.

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Mammadova, Chinara; Kuijper, Arjan [Prüfer]; Ben Hmida, Helmi [Betreuer]

New Approach for Optimizing Usage of Situation Recognition Algorithms within IoT Domains

2016

Darmstadt, TU, Master Thesis, 2016

Over the past few years technological advancements have supported the growth of the Internet of Things (IoT). The Internet of Things consists of (smart) objects embedded with sensors, actuators and controllers. These objects are connected to the Internet and are able to communicate with each other. The interconnection and communication of objects enable the creation of different application domains within the Internet of Things. Smart living is one of the major application areas for the Internet of Things. Sensors, actuators and controllers in a smart living environment (e.g. smart homes) are deployed anywhere; on objects or even on persons. As sensors have the capability to sense the environment, they can be used to collect useful information on location, motion, temperature, humidity, light, etc. Actuators can perform different actions based on data gathered from sensors, and controllers can process that data. Real-time situation awareness is one of the key tasks in a smart living environment. Real-time recognition of situations is especially important in ambient assisted living environments, where elderly or disabled people need support in their everyday lives. Recognition of situations in real-time enables immediate identification of critical situations and provides just-in-time assistance. To detect situations, data needs to be monitored, collected, analyzed and processed. Due to the increasing number of IoT connected devices, the amount of generated data is increasing too. Processing huge amounts of data is complex due to the inefficiency of continuously-running pattern/situation recognition algorithms, high requirement for processing capability and high frequency of the recognition process. Situation recognition algorithms must be executed constantly to handle the continuously generated data. For real-time recognition of situations in particular, these algorithms need to be executed permanently for all received data. The continuously-running recognition algorithms require high processing capabilities. The resource consumption of these algorithms is especially high when they are running on large sets of data. To overcome these problems there is a need for more intelligent approaches that are able to decide - based on target situation recognition purposes - which data is important and should be processed and which algorithm should be used to process this data. This study proposes an approach for optimizing the usage of situation recognition algorithms in Internet of Things domains. The key idea of our approach is to select important data, based on situation recognition purposes, and to execute the situation recognition algorithms after all relevant data have been collected. The main advantage of our approach is that situation recognition algorithms will not be executed each time new data is received. This allows reduction of the frequency of execution of the situation recognition algorithms, thus saving computational resources, such as CPU, memory, storage, bandwidth and power. Another advantage of our approach is that it can be applied to recognize situations in real-time, which is useful for ambient assisted living environments. We apply the proposed approach to implement a use case scenario on top of the universAAL IoT platform, which is an open-source platform for the development of IoT solutions.

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Yimam, Seid Muhie; Ulrich, Heiner; Landesberger, Tatiana von; Rosenbach, Marcel; Regneri, Michaela; Panchenko, Alexander; Fahrer, Uli; Biemann, Chris; Ballweg, Kathrin

new/s/leak - Information Extraction and Visualization for Investigative Data Journalists

2016

The 54th Annual Meeting of the Association for Computational Linguistics

Annual Meeting of the Association for Computational Linguistics <54, 2016, Berlin, Deutschland>

We present new/s/leak, a novel tool developed for and with the help of journalists, which enables the automatic analysis and discovery of newsworthy stories from large textual datasets. We rely on different NLP preprocessing steps such named entity tagging, extraction of time expressions, entity networks, relations and metadata. The system features an intuitive web-based user interface based on network visualization combined with data exploring methods and various search and faceting mechanisms. We report the current state of the software and exemplify it with the WikiLeaks PlusD (Cablegate) data.

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Online Learning Verfahren für markerloses Tracking

2016

Angewandte Virtuelle Techniken im Produktentstehungsprozess

Kap. 5 beschreibt die Forschungsthemen zum Schwerpunkt Tracking. Darunter ist das Erfassen der Position und Orientierung von Objekten bzw. des Anwenders im dreidimensionalen Raum zu verstehen. Die Arbeiten bilden damit die Grundlage für darauf aufbauende Funktionen wie beispielsweise die lagekorrekte Einblendung zusätzlicher Informationen oder die intuitive Interaktion durch Gesten. Neben Ansätzen zur Weiterentwicklung der Algorithmen des markerlosen Trackings werden ergänzende Sensoriken wie Wegaufnehmer an Robotern, Inertialsensoriken an Kameras betrachtet. Ein weiterer Ansatz untersucht die Hinzunahme von CAD-Daten zur Verbesserung des bildbasierten Trackings.

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Königstein, Robert; Stork, André [1. Gutachter]; Sevilmis, Neyir [2. Gutachter]

Optical Recognition of Transport Boxes for Logistics Applications

2016

Darmstadt, TU, Bachelor Thesis, 2016

This bachelor thesis will propose a novel approach for recognizing transport boxes on pallets in goods receipt in logistics. Especially if pallets are not labeled with barcodes or RFID-tags, it is very time consuming, to manually recognize and count the incoming boxes. Therefore, a measuring station, in which the pallets are recognized, is presented. Two images of opposite sides of the pallet are taken and further processed by a modular software to recognize and count the transport boxes. The process is divided into three main steps. In the first step, the input images are segmented to gain one image snippet for each transport box present in the image. This is done by morphologically transforming the input images and extracting the boundaries of the boxes. In a second step, each of the prior calculated image segments is classified by a multi-machine support vector machine, trained with histograms of visual words received by a Bag-of-Words model, in combination with colour information. Finally, the classification results of the images taken from two opposite perspectives of the pallet are merged to get an overall statement, of how many and which type of transport boxes are stacked on the pallet.

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Scheckenbach, Kathrin; Colter, Lena; Okpanyi, V.; Schipper, Jörg; Klenzner, Thomas; Wesarg, Stefan; Jung, Florian; Brakenhoff, R.; Mes, S.; Wiel, M. van de; Karampali, V.; Ruggeri, A.; Lehnerdt, G.; Windfuhr, J.; Gronau, S.

Oramod - Software-basierte multimodale Prädiktion des Outcome von Patienten mit Mundhöhlenkarzinomen

2016

Curac 2016

Jahrestagung der Deutschen Gesellschaft für Computer- und Roboter Assistierte Chirurgie (CURAC) <15, 2016, Bern, Schweiz>

Valide Biomarker sind für die personalisierte Therapie bei Mundhöhlenkarzinomen noch nicht etabliert. Individuelle klinische, Bildgebungs-basierte oder genetische Marker beeinflussen das Outcome des Patienten. Um alle diese Parameter in einem holistischen Modell auszuwerten, ist eine IT-basierte, multimodale Strategie unabdingbar. Innerhalb des EU-geförderten "OraMod"-Projektes wurde in einer Multicenter-Studie anhand der Daten von 239 Patienten einen Algorithmus erstellt, der das Outcome vorhersagt. Klinische Daten und eine 12 Gene umfassende Gensignatur konnten definiert werden. Zur unkomplizierten Umsetzung wurde ein benutzerfreundlicher RT-PCR-Cycler (Größe: ca. 12 x 8 x 10 cm, Gewicht: <500g) entwickelt. Die Bildgebungsdaten fließen nach semi-automatisierter Segmentierung ein. Eine Validierung erfolgt an 126 prospektiv eingeschlossenen Patienten. Die Oramod-Software kann die Personalisierung der Therapie und Nachsorge von Mundhöhlenkarzinomen durch eine Vorhersage des Outcome anhand von bei Erstdiagnose erhobenen Daten verbessern. Aufgrund der intuitiven, übersichtlichen und ansprechenden Visualisierung kann sie zudem als elektronische Patientenakte verwendet werden.

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Brodkorb, Felix; Kuijper, Arjan; Andrienko, Gennady; Andrienko, Natalia; Landesberger, Tatiana von

Overview with Details for Exploring Geo-located Graphs on Maps

2016

Information Visualization

Geo-located graph drawings often suffer from map visualization problems, such as overplotting of nodes as well as edges and location of parts of the graph being outside of the screen. One cause of these problems is often an irregular distribution of nodes on the map. Zooming and panning do not solve the problems, as they either only show the overview of the whole graph or only the details of a part of the graph. We present an interactive graph drawing technique that overcomes these problems without affecting the overall geographical structure of the graph. First, we introduce a method that uses insets to visualize details of small or remote areas. Second, to prevent the subgraphs within insets from overplotting and edge crossing, we introduce a local area re-arrangement. Moreover, insets are automatically drawn/hidden and repositioned in accordance with the user's navigation. We test our technique on real-world geo-located graph data and show the effectiveness of our approach for showing overview and details at the same time. Additionally, we report on expert feedback concerning our approach.

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Große-Puppendahl, Tobias; Dellangnol, Xavier; Hatzfeld, Christian; Fu, Biying; Kupnik, Mario; Kuijper, Arjan; Hastall, Matthias R.; Scott, James; Gruteser, Marco

Platypus - Indoor Localization and Identification through Sensing Electric Potential Changes in Human Bodies

2016

Mobile Systems, Applications, and Services

International Conference on Mobile Systems, Applications, and Services (MobiSys) <14, 2016, Singapore>

Platypus is the first system to localize and identify people by remotely and passively sensing changes in their body electric potential which occur naturally during walking. While it uses three or more electric potential sensors with a maximum range of 2 m, as a tag-free system it does not require the user to carry any special hardware. We describe the physical principles behind body electric potential changes, and a predictive mathematical model of how this affects a passive electric field sensor. By inverting this model and combining data from sensors, we infer a method for localizing people and experimentally demonstrate a median localization error of 0.16m. We also use the model to remotely infer the change in body electric potential with a mean error of 8.8% compared to direct contact-based measurements. We show how the reconstructed body electric potential differs from person to person and thereby how to perform identification. Based on short walking sequences of 5 s, we identify four users with an accuracy of 94 %, and 30 users with an accuracy of 75%. We demonstrate that identification features are valid over multiple days, though change with footwear.

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Richter, Stephan; Vineet, Vibhav; Roth, Stefan; Koltun, Vladlen

Playing for Data: Ground Truth from Computer Games

2016

Computer Vision - ECCV 2016. Proceedings Part II

European Conference on Computer Vision (ECCV) <14, 2016, Amsterdam, The Netherlands>

Recent progress in computer vision has been driven by highcapacity models trained on large datasets. Unfortunately, creating large datasets with pixel-level labels has been extremely costly due to the amount of human effort required. In this paper, we present an approach to rapidly creating pixel-accurate semantic label maps for images extracted from modern computer games. Although the source code and the internal operation of commercial games are inaccessible, we show that associations between image patches can be reconstructed from the communication between the game and the graphics hardware. This enables rapid propagation of semantic labels within and across images synthesized by the game, with no access to the source code or the content. We validate the presented approach by producing dense pixel-level semantic annotations for 25 thousand images synthesized by a photorealistic openworld computer game. Experiments on semantic segmentation datasets show that using the acquired data to supplement real-world images significantly increases accuracy and that the acquired data enables reducing the amount of hand-labeled real-world data: models trained with game data and just 1/3 of the CamVid training set outperform models trained on the complete CamVid training set.

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Chua, Soon Hau; Perrault, Simon T.; Matthies, Denys J.C.; Zhao, Shengdong

Positioning Glass: Investigating Display Positions of Monocular Optical See-Through Head-Mounted Display

2016

Proceedings of the Fourth International Symposium on Chinese CHI

International Symposium of Chinese CHI (ChineseCHI) <4, 2016, San Jose, CA, USA>

The physical position of the display on a monocular OSTHMD in relative to our eye is an important factor of the performance and usability in dual-task scenarios. We investigated 9 different display positions in a modern dual-task scenario with 27 participants. The experiment-involved participants responding to 3 different types of notifications displayed on the HMD while performing a visually intensive primary task. We found that although the notifications at the middle and bottom center positions were noticed quicker, the top and the peripheral positions were more comfortable, unobtrusive, and preferred. In particular, middle-right strikes the best balance between performance and usability in the dual-task scenario we studied. Our findings and discussions demonstrated the need for further work and a more rigorous investigation in dual-task scenarios with characteristics dissimilar to ours.

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Damer, Naser; Dimitrov, Kristiyan

Practical View on Face Presentation Attack Detection

2016

Proceedings of the British Machine Vision Conference 2016 [Online]

British Machine Vision Conference (BMVC) <27, 2016, York, UK>

Face recognition is one of the most socially accepted forms of biometric recognition. The recent availability of very accurate and efficient face recognition algorithms leaves the vulnerability to presentation attacks as the major challenge to face recognition solutions. Previous works have shown high preforming presentation attack detection PAD solutions under controlled evaluation scenarios. This work tried to analyze the practical use of PAD by investigating the more realistic scenario of cross-database evaluation and presenting a state-of-the-art performance comparison. The work also investigated the relation between the video duration and the PAD performance. This is done along with presenting an optical flow based approach that proves to outperform state-of-the-art solutions in most experiment settings.

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Thaller, Wolfgang; Augsdörfer, Ursula H.; Fellner, Dieter W.

Procedural Mesh Features Applied to Subdivision Surfaces using Graph Grammars

2016

Computers & Graphics

Shape Modeling International (SMI) <2016, Berlin, Germany>

A typical industrial design modelling scenario involves defining the overall shape of a product followed by adding detail features. Procedural features are well-established in computer aided design (CAD) involving regular forms, but are less applicable to free-form modelling involving subdivision surfaces. Current approaches do not generate sparse subdivision control meshes as output, which is why free-form features are manually modelled into subdivision control meshes by domain experts. Domain experts change the local topology of the subdivision control mesh to incorporate features into the surface, without increasing the mesh density unnecessarily and carefully avoiding the appearance of artefacts. In this paper we show how to translate this expert knowledge to grammar rules. The rules may then be invoked in an interactive system to automatically apply features to subdivision surfaces.

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

Procedural Modeling of Round Building Geometry

2016

2016 International Conference on Cyberworlds

International Conference on Cyberworlds (CW) <2016, Chongqing, China>

Creation of procedural 3D building models can significantly lessen the costs of modeling, since it allows generating a variety of similar shapes from one procedural description. The common field of application for procedural modeling is modeling of straight building facades, which are very well suited for shape grammars - a special kind of procedural modeling system. In order to generate round building geometry, we present a way to setup different coordinate systems in shape grammars. Besides Cartesian, these are primarily cylindrical and spherical coordinate systems for generation of structures like towers or domes, that can procedurally adapt to different dimensions and parameters. The users can apply common splitting idioms from shape grammars in their familiar way, for creating round instead of straight geometry.

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Große-Puppendahl, Tobias; Braun, Andreas; Dellangnol, Xavier

Prototyping Capacitive Sensing Applications with OpenCapSense

2016

GetMobile

OpenCapSense is a prototyping platform to develop innovative applications that rely on perceiving humans with electric fields. Despite today's use of capacitive sensing mostly as a method to detect touch, it offers many interesting facets that range from mid-air interaction to contactless indoor localization and identification. The platform provides active sensors to detect human interactions at distances of more than 40 cm, by generating electric fields. Passive sensors allow for measuring changes in electric fields that occur naturally in the environment, enabling detection distances up to 2 m.

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Möckel, Jerome; Burkhardt, Dirk [Betreuer]

Prozessorientierte Informationsvisualisierung

2016

Darmstadt, Hochschule, Bachelor Thesis, 2016

Ziel der vorliegenden Bachelorarbeit war es, ein Prozessmodell zu entwickeln und dies anschließend zu visualisieren, was Nutzern ein effizienteres und schnelleres Arbeiten durch geeignete Tools ermöglichen soll. Die Erreichung dieses Ziels ist durch mehrere Faktoren bedingt. Zum einen müssen die Anwendungsprozesse erkannt werden, woraufhin sich die Frage stellt, wie man diese Prozesse unterstützen kann. Zum anderen ist es auch wichtig, die Aufgaben zu erfassen, welche der Nutzer zu lösen versucht. Weiterhin spielt es auch eine große Rolle, welche Tools für diese Aufgaben geeignet sind. Eine geeignete Anwendung muss sich also an den Nutzer anpassen, um dessen Einstiegshürden zu minimieren und das effektivere und effizientere Arbeiten zu ermöglichen. Um das Ziel zu erreichen, wurden die Anwendungsprozesse mithilfe von manuellem Process Mining identifiziert. Anhand dieser Daten konnte ein Prozessmodell entwickelt werden, welches daraufhin durch eine Visualisierung abgebildet wurde. Prozessorientierte Adaption ermöglicht das Observieren der Prozesszustände und der Nutzerinteraktionen. Der Nutzer wird dabei auch durch die Auswahl der geeigneten Tools unterstützt. Dieser adaptive Schritt wird durch die Regeln, die dem entwickelten Prozessmodell zugrunde liegen, bewirkt. Den Nachweis der Zielerfüllung soll eine abschließende empirische Vergleichsstudie erbringen.

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Siegmund, Dirk; Kähm, Olga; Handtke, David

Rapid Classification of Textile Fabrics Arranged in Piles

2016

Proceedings of the 13th International Joint Conference on e-Business and Telecommunications Volume 5

International Joint Conference on e-Business and Telecommunications (ICETE) <13, 2016, Lisbon, Portugal>

Research on the quality assurance of textiles has been a subject of much interest, particularly in relation to defect detection and the classification of woven fibers. Known systems require the fabric to be flat and spread-out on 2D surfaces in order for it to be classified. Unlike other systems, this system is able to classify textiles when they are presented in piles and in assembly-line like environments. Technical approaches have been selected under the aspects of speed and accuracy using 2D camera image data. A patch-based solution was chosen using an entropy-based pre-selection of small image patches. Interest points as well as texture descriptors combined with principle component analysis were part of this evaluation. The results showed that a classification of image patches resulted in less computational cost but reduced accuracy by 3.67%.

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Weber, Nicolas; Wächter, Michael; Amend, Sandra C.; Guthe, Stefan; Goesele, Michael

Rapid, Detail-Preserving Image Downscaling

2016

ACM Transactions on Graphics

Conference and Exhibition on Computer Graphics and Interactive Techniques in Asia (SIGGRAPH ASIA) <9, 2016, Macao>

Image downscaling is arguably the most frequently used image processing tool. We present an algorithm based on convolutional filters where input pixels contribute more to the output image the more their color deviates from their local neighborhood, which preserves visually important details. In a user study we verify that users prefer our results over related work. Our efficient GPU implementation works in real-time when downscaling images from 24M to 70 k pixels. Further, we demonstrate empirically that our method can be successfully applied to videos.

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Zhao, Xueqing; Mavridis, Pavlos; Schreck, Tobias; Kuijper, Arjan

RDEPS: A Combined Reaction-Diffusion Equation and Photometric Similarity Filter for Optical Image Restoration

2016

Advances in Visual Computing. 12th International Symposium, ISVC 2016

International Symposium on Visual Computing (ISVC) <12, 2016, Las Vegas, NV, USA>

Restoration of optical images degraded by atmospheric turbulence and various types of noise is still an open problem. In this paper, we propose an optical image restoration method based on a Reaction-Diffusion Equation and Photometric Similarity (RDEPS). We exploit photometric similarity and geometric closeness of the optical image by combining a photometric similarity function and a appropriately defined reaction-diffusion equation. Our resulting RDEPS filter is used to restore images degraded by atmospheric turbulence and noise, including Gaussian noise and impulse noise. Extensive experimental results show that our method outperforms other recently developed methods in terms of PSNR and SSIM. Moreover, the computational efficiency analysis shows that our RDEPS provides efficient restoration of optical images.

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Mostajabodaveh, Seyedmorteza; Dietrich, Andreas [Betreuer]; Michel, Frank [Betreuer]

Real-Time Parallel Streamsurface Computation

2016

München, TU, Master Thesis, 2016

Streamsurfaces are one of the powerful visualization tools, which are used to gain insight into characteristics and features of flow fields. In practice, streamsurfaces are approximated by triangulating adjacent pairs of integral curves, originating from a seeding line. The generation of integral curves bears quite some similarities to ray tracing algorithms used in physically based renderers. Although, the techniques used in ray tracing may not have good performance in the streamline computation context due to their different computational nature, they can be optimized for streamline computation by introducing some modifications. In this master thesis, I present my work on accurate streamsurface computation and rendering in real-time, by exploiting the scalability and portability features of parallel architectures in heterogeneous computing, and utilizing concepts from physically based rendering. To improve the efficiency, I use a scheduler to divide the streamsurface computation and rendering tasks on different devices proportional to their computation powers. Additionally, I apply acceleration structures and the concepts of caching to improve the efficiency and utilization of streamsurface generation on modern GPUs and CPUs to achieve real-time results. Furthermore, the possible impact of applying ray-packing and ray-sorting to the streamline computation is investigated.

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Reducing Over- and Undersegmentations of the Liver in Computed Tomographies Using Anatomical Knowledge

2016

XIV Mediterranean Conference on Medical and Biological Engineering and Computing

Mediterranean Conference on Medical and Biological Engineering and Computing (MEDICON) <14, 2016, Paphos, Cyprus>

In the last decades several liver segmentation methods have been proposed. The proposed methods go from region growing to the more complex statistical shape models. Despite the robustness of those algorithms, liver segmentation is still a challenging task especially in areas in which its neighboring organs have similar intensities, e.g., heart and ribcage. In addition to this, pathological organs that contain tumors near their surface present additional difficulties. This paper presents a solution to increase the accuracy of those algorithms in the aforementioned areas. The effect of the improvement using the generated heart and ribcage walls (7% and 1% respectively) is evaluated on 9 clinical computer tomographies (CT). The improvement (12 %) when tumors are near the surface, on the contrary, is tested on 7 clinical CT images.

  • 978-3-319-32703-7
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Webel, Sabine; Staykova, Yana; Bockholt, Ulrich

Registrierung von Handfertigkeiten und Geschicklichkeiten zur Realisierung von "Action Driven Interfaces"

2016

Angewandte Virtuelle Techniken im Produktentstehungsprozess

Kap. 3 betrachtet die Forschungsarbeiten zur Integration von Informationen aus dem Produktlebenszyklus in virtuellen Modellen. Der Schwerpunkt liegt dabei auf schrittweise strukturierten Handlungsabläufen, wie sie typisch für Montage-, Demontage und bestimmte Bedienhandlungen sind. In den Arbeitspaketen wird untersucht, wie Arbeitspläne aus Product-Lifecycle-Management-Systemen für Abläufe in virtuellen Modellen verwendet werden können. Weiterhin werden Ansätze zur Extraktion von Handlungsabläufen aus kamerabasierten Daten und semantischen Modellen untersucht.

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Volk, Rebekka; Sevilmis, Neyir; Stier, Christian; Bayha, Ansilla

ResourceApp - Entwicklung eines Mobilen Systems zur Erfassung und Erschliessung von Ressourceneffizienzpotenzialen beim Rückbau von Infrastruktur und Produkten

2016

Innovative Technologien für Ressourceneffizienz - Strategische Metalle und Mineralien

Der Anteil an Bau- und Abbruchabfallen beträgt mit rund 200 Mio. t mehr als 50 % der jährlich anfallenden Abfälle in Deutschland [Statistik Portal 2015]. Dabei sind Rückbau- und Abbruchprojekte durch einen grosen Zeit- und Kostendruck gekennzeichnet. Bei der heute üblichen Erfassung von Rückbauobjekten durch Begehung werden die verbauten, oft werthaltigen Materialien grob geschätzt, was zu einer grosen Abweichung zur tatsächlichen Materialzusammensetzung führen kann. Dennoch dienen diese Schatzwerte zurzeit als Grundlage fur das Angebot und die Projekt- und Verwertungsplanung der Rückbauunternehmer. Im Projekt ResourceApp wurde ein Demonstrator entwickelt, der erstmals die mobile, dreidimensionale (3D) und semantische Erfassung von Gebäuden und Bauteilen und eine anschliesende Umbau- oder Rückbauplanung in Echtzeit ermöglicht. Das System besteht aus einem Sensor und Software-Modulen auf einem Laptop, die die Datenverarbeitung der Sensordaten erlauben, um das Rohstoffpotenzial eines Gebäudes zu bestimmen und dessen Rückbau zu planen. Für das Gebäudeaudit wird der Innenraum erfasst und in 3D rekonstruiert sowie dessen Inventar bestimmt. Notwendige Rückbaumasnahmen zur Wiedergewinnung der Rohstoffe werden ermittelt und geplant und daraus die Rückgewinnungskosten der Materialien bestimmt. Im Fall des Praxistests, des Krankenhauses von Bad Pyrmont, wurde das Gebäude mit dem Sensor aufgenommen, automatisiert inventarisiert und nach der Begehung rückgebaut. In der Praxis war es möglich, große Bauteile (Wände, Decken, Böden, Türen, Fenster) mit der App zu erkennen. Aufgrund schwieriger Raumgeometrien (kleine, verwinkelte und langgestreckte gleichförmige Räume), die die Aufnahme mit dem Kinect-Sensor erschwerten, konnten aber ca. 20 % der großen Bauteile nicht erkannt werden. Zudem konnte ein Großteil der zu erkennenden Anschlüsse (wie Steckdosen), die Rückschlusse auf die technische Gebäudeausstattung und somit auf die werthaltigen Rohstoffe des Gebäudes geben sollten, nicht erkannt werden. Hier besteht weiterer erheblicher Forschungsbedarf, da die eingesetzten Sensoren eine noch nicht ausreichende Auflösung aufweisen. Koordiniert wurde das Projekt ResourceApp vom Fraunhofer-Institut fur Chemische Technologie ICT. Weitere Partner waren das Fraunhofer-Institut fur Graphische Datenverarbeitung IGD, das Institut fur Industriebetriebslehre und Industrielle Produktion IIP des Karlsruher Instituts fur Technologie KIT, die Abbruch- bzw. Sanierungsunternehmen Werner Otto GmbH und COSAWA Sanierung GmbH sowie das Umwelt-Beratungsbüro GPB Arke.

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Bachmann, Matthias; Klien, Eva; Stein, Andreas

Risikobewertung mit 3D-Stadtmodellen

2016

GIS.Business - GIS.Science

Die Sicherheitsforschungsprogramme auf nationaler und europäischer Ebene beschreiben besonders städtische Gebiete als zunehmend verwundbar gegenüber drei wesentlichen Bedrohungen: Naturkatastrophen, technologische Ereignisse und Terrorismus. Das Fraunhofer-Institut für Graphische Datenverarbeitung IGD und das Fraunhofer Ernst-Mach-Institut EMI entwickeln zusammen ein Portal, das eine Risikobewertung auf Basis eines 3D-Stadtmodells erstellen soll.

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Rixels: Towards Secure Interactive 3D Graphics in Engineering Clouds

2016

The IPSI BgD Transactions on Internet Research

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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Seo, Byung-Kuk; Wuest, Harald

Robust 3D Object Tracking Using an Elaborate Motion Model

2016

2016 IEEE International Symposium on Mixed and Augmented Reality

IEEE International Symposium on Mixed and Augmented Reality (ISMAR) <15, 2016, Merida, Mexico>

This paper proposes a new method for robust 3D object tracking from a single RGB image when an object model is available. The proposed method is based on image alignment between consecutive frames over a 3D target object. Different from conventional methods that only rely on image intensity for the alignment, we model intensity variations using the surface normal of the object. From this model, we also define a new constraint for the pose estimation, leading to significant improvement in the tracking robustness. In experiments, we demonstrate the benefits of our method by evaluating it under challenging tracking conditions.

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Scaling up IoT: Impact of Semantic Open Platforms

2016

VDE-Kongress 2016 - Internet der Dinge

VDE-Kongress <2016, Mannheim>

The Internet of Things (IoT) consists of connected objects such as sensors and actuators, as well as smart services. Due to its characteristics, requirements and impact on real life system, the IoT has gained significant attention over the last few years. The main reported issue is the exponential growing number of "Things". Among the open platform technologies, a semantic open platform offers the opportunity to reduce the system complexity, ensuring a direct communication between heterogeneous components without knowing each other, and sharing data based on a "common" semantic model without any need for a specific API. The major goal of this contribution is to clarify the previously highlighted advantages and to strategically recommend the usage of semantic open platforms thus facilitating the growth of the IoT.

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Schlussbericht FLEXMOT

2016

Die Aufgaben des Fraunhofer IGD im Rahmen des Projektes FLEXMOT waren die Entwicklung von Modulen für den Datenempfang, die Datenverwaltung und die Datenvisualisierung. Seit der gemeinsamen Festlegung durch alle Projektpartner im Konsortialmeeting am 29.10.2013 zeichnete das Fraunhofer IGD auch für das Gesamtprojektmanagement verantwortlich. Dies beinhaltete die organisatorischen und koordinierenden Aufgaben innerhalb des Konsortiums. Das Vorhaben wurde vor dem Hintergrund gestartet, dass durch die wachsende Expansion der Offshore-Exploration der Öl & Gas-Industrie, dem wachsenden gesellschaftlichen Umweltbewusstsein und Großunfällen wie dem Macondo-Blowout 2010 im Golf von Mexiko (Deep Horizon Unglück) offenbar wurde, wie groß der Bedarf für Umweltmonitoring-Technik ist, die besser und schneller einsetzbar, rekonfigurierbar und benutzbar sind (modulares Grundkonzept, geringe Rüstzeiten, lange Standzeiten) und zugleich größere Bereiche abdecken und eine schnelle Datenverfügbarkeit bieten. Daher initiierte der Hersteller von Gas-Sensorik Contros GmbH aus Kiel, der über entsprechendes Branchen-KnowHow und Kontakte im Öl&Gas-Bereich verfügte, zusammen mit den Unternehmen Oktopus GmbH und LEONI Special Cables GmbH und den Wissenschaftspartnern GEOMAR (Kiel) und Fraunhofer IGD (Rostock) das Projekt FlexMoT. Durch dieses Konsortium war sichergestellt, dass alle Bereiche (Mechanik, Sensorik, Prozess-KnowHow, Software für Datenmanagement und -auswertung und wissenschaftliche Unterwasser-Expertise) im Projekt vorhanden waren. Zudem war der anvisierte industrielle Markt für funktionierende und langzeittaugliche Monitoringinstrumente aufgrund der hohen Ölpreise sehr vielversprechend. Ziel war es, ein entsprechendes flexibles und modulares System zu entwickeln, welches die entscheidenden Schwächen bisheriger System umgeht und auch für den Einsatz durch nichtwissenschaftliche Anwender (Industriekunden) geeignet ist. Im Projekt sollte zum einen eine Erprobung der Entwicklungen auf ihre Unterwasser- und Einsatztauglichkeit hin stattfinden. Zum andere sollte die Funktionstüchtigkeit des Gesamtsystems nachgewiesen werden. Für diese Feldtests war es notwendig, mit einem geeigneten Schiff im angestrebten Einsatzumfeld, der Nordsee, und in typischen Wassertiefen der Kontinentalschelf-Offshore-Förderung zu testen. Das GEOMAR organisierte und stellte dafür das Forschungsschiff FS ALKOR und Schiffszeiten sowie wissenschaftliches Equipment für die Referenzmessungen zur Verfügung.

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Hermanns, Lukas; Franke, Tobias; Kuijper, Arjan

Screen Space Cone Tracing for Glossy Reflections

2016

Virtual Augmented and Mixed Reality. Proceedings

International Conference Virtual Augmented and Mixed Reality (VAMR) <8, 2016, Toronto, ON, Canada>

Indirect lighting (also Global Illumination (GI)) is an important part of photo-realistic imagery and has become a widely used method in real-time graphics applications, such as Computer Aided Design (CAD), Augmented Reality (AR) and video games. Path tracing can already achieve photo-realism by shooting thousands or millions of rays into a 3D scene for every pixel, which results in computational overhead exceeding real-time budgets. However, with modern programmable shader pipelines, a fusion of ray-casting algorithms and rasterization is possible, i.e. methods, which are similar to testing rays against geometry, can be performed on the GPU within a fragment (or rather pixel-) shader. Nevertheless, many implementations for real-time GI still trace perfect specular reflections only. In this work the advantages and disadvantages of different reflection methods are exposed and a combination of some of these is presented, which circumvents artifacts in the rendering and provides a stable, temporally coherent image enhancement. The benefits and failings of this new method are clearly separated as well. Moreover the developed algorithm can be implemented as pure post-process, which can easily be integrated into an existing rendering pipeline.

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SeismoPen: Pulse Recognition via a Smart Pen

2016

Proceedings of the 9th International Conference on PErvasive Technologies Related to Assistive Environments

ACM International Conference on PErvasive Technologies Related to Assistive Environments (PETRA) <9, 2016, Corfu, Greece>

We propose SeismoPen, an enhanced ballpoint pen, which is capable of calculating the patient's heart rate. This is enabled when being pressed the pen towards the patient's throat so it can sense and analyze the seismographic micro-eruption caused by the pulsing blood. We developed a suitable algorithm and tested three sensor setups in which we attached (1) a force-sensing resistor (FSR), (2) an accelerometer, and (3) a piezoelectric transducer to the pen's head. We also conducted a user study, which resulted in suggesting SeismoPen to be potentially more accepted by users, since it is less obtrusive than alternative measurement methods. In contrast to medical devices, this simple pen looks less perilous and potentially reduces the risk of triggering symptoms of a white coat hypertension.

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SeismoTracker: Upgrade Any Smart Wearable to Enable a Sensing of Heart Rate, Respiration Rate, and Microvibrations

2016

Proceedings of the 2016 CHI Conference Extended Abstracts on Human Factors in Computing

Conference on Human Factors in Computing Systems (CHI) <34, 2016, San Jose, CA, USA>

In this paper we present a method to enable any smart Wearable to sense vital data in resting states. These resting states (e.g. sleeping, sitting calmly, etc.) imply the presence of low-amplitude body-motions. Our approach relies on seismocardiography (SCG), which only requires a built-in accelerometer. Compared to commonly applied technologies, such as photoplethysmography (PPG), our approach is not only tracking heart rate (HR), but also respiration rate (RR), and microvibrations (MV) of the muscles, while being also computational inexpensive. In addition, we can calculate several other parameters, such as HR variability and RR variability. Our extracted vital parameters match with the vital data gathered from clinical state-of-the art technology. These data allow us to gain an impression on the user's activity, quality of sleep, arousal and stress level over the whole day, week, month, or year. Moreover, we can detect whether a device is actually worn or doffed, which is crucial when connecting such data with health services. We implemented our method on two current smartwatches: a Simvalley AW420 RX as well as on a LG G Watch R and recorded user data for several months. A web platform enables to keep track of one's data.

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Silva, Nelson; Shao, Lin; Schreck, Tobias; Eggeling, Eva; Fellner, Dieter W.

Sense.me - Open Source Framework for the Exploration and Visualization of Eye Tracking Data

2016

IEEE Conference on Visualization (VIS) <2016, Baltimore, USA>

We present a new open-source prototype framework to explore and visualize eye-tracking experiments data. Firstly, standard eyetrackers are used to record raw eye gaze data-points on user experiments. Secondly, the analyst can configure gaze analysis parameters, such as, the definition of areas of interest, multiple thresholds or the labeling of special areas, and we upload the data to a search server. Thirdly, a faceted web interface for exploring and visualizing the users' eye gaze on a large number of areas of interest is available. Our framework integrates several common visualizations and it also includes new combined representations like an eye analysis overview and a clustered matrix that shows the attention time strength between multiple areas of interest. The framework can be readily used for the exploration of eye tracking experiments data. We make available the source code of our prototype framework for eye-tracking data analysis.

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Sensorfusion zur Realisierung hybrider Trackingverfahren

2016

Angewandte Virtuelle Techniken im Produktentstehungsprozess

Kap. 5 beschreibt die Forschungsthemen zum Schwerpunkt Tracking. Darunter ist das Erfassen der Position und Orientierung von Objekten bzw. des Anwenders im dreidimensionalen Raum zu verstehen. Die Arbeiten bilden damit die Grundlage für darauf aufbauende Funktionen wie beispielsweise die lagekorrekte Einblendung zusätzlicher Informationen oder die intuitive Interaktion durch Gesten. Neben Ansätzen zur Weiterentwicklung der Algorithmen des markerlosen Trackings werden ergänzende Sensoriken wie Wegaufnehmer an Robotern, Inertialsensoriken an Kameras betrachtet. Ein weiterer Ansatz untersucht die Hinzunahme von CAD-Daten zur Verbesserung des bildbasierten Trackings.

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Langguth, Fabian; Sunkavalli, Kalyan; Hadap, Sunil; Goesele, Michael

Shading-Aware Multi-View Stereo

2016

Computer Vision - ECCV 2016. Proceedings Part III

European Conference on Computer Vision (ECCV) <14, 2016, Amsterdam, The Netherlands>

We present a novel multi-view reconstruction approach that effectively combines stereo and shape-from-shading energies into a single optimization scheme. Our method uses image gradients to transition between stereo-matching (which is more accurate at large gradients) and Lambertian shape-from-shading (which is more robust in flat regions). In addition, we show that our formulation is invariant to spatially varying albedo without explicitly modeling it. We show that the resulting energy function can be optimized efficiently using a smooth surface representation based on bicubic patches, and demonstrate that this algorithm outperforms both previous multi-view stereo algorithms and shading based refinement approaches on a number of datasets.

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SmartMove: A Smartwatch Algorithm to Distinguish Between High- and Low-Amplitude Motions as well as Doffed-States by Utilizing Noise and Sleep

2016

iWOAR 2016

International Workshop on Sensor-based Activity Recognition (iWOAR) <3, 2016, Rostock, Germany>

In this paper, we describe a self adapting algorithm for smart watches to define individual transitions between motion intensities. The algorithm enables for a distinction between high-amplitude motions (e.g. walking, running, or simply moving extremities) low-amplitude motions (e.g. human microvibrations, and heart rate) as well as a general doffedstate. A prototypical implementation for detecting all three motion types was tested with a wrist-worn acceleration sensor. Since the aforementioned motion types are userspecific, SmartMove incorporates a training module based on a novel actigraphy-based sleep detection algorithm, in order to learn the specific motion types. In addition, our proposed sleep algorithm enables for reduced power consumption since it samples at a very low rate. Furthermore, the algorithm can identify suitable timeframes for an inertial sensor-based detection of vital-signs (e.g. seismocardiography or ballistocardiography).

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Stereo-Image Normalization of Voluminous Objects Improves Textile Defect Recognition

2016

Advances in Visual Computing. 12th International Symposium, ISVC 2016

International Symposium on Visual Computing (ISVC) <12, 2016, Las Vegas, NV, USA>

The visual detection of defects in textiles is an important application in the textile industry. Existing systems require textiles to be spread flat so they appear as 2D surfaces, in order to detect defects. In contrast, we show classification of textiles and textile feature extraction methods, which can be used when textiles are in inhomogeneous, voluminous shape. We present a novel approach on image normalization to be used in stain-defect recognition. The acquired database consist of images of piles of textiles, taken using stereo vision. The results show that a simple classifier using normalized images outperforms other approaches using machine learning in classification accuracy.

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Supporting Collaborative Political Decision Making - An Interactive Policy Process Visualization System

2016

VINCI 2016. The 9th International Symposium on Visual Information Communication and Interaction

International Symposium on Visual Information Communication and Interaction (VINCI 2016) <9, 2016, Dallas, Texas>

The process of political decision making is often complex and tedious. The policy process consists of multiple steps, most of them are highly iterative. In addition, different stakeholder groups are involved in political decision making and contribute to the process. A series of textual documents accompanies the process. Examples are official documents, discussions, scientific reports, external reviews, newspaper articles, or economic white papers. Experts from the politi- cal domain report that this plethora of textual documents often exceeds their ability to keep track of the entire policy process. We present PolicyLine, a visualization system that supports different stakeholder groups in overview-and-detail tasks for large sets of textual documents in the political decision making process. In a longitudinal design study conducted together with domain experts in political decision making, we identfied missing analytical functionality on the basis of a problem and domain characterization. In an iterative design phase, we created PolicyLine in close collaboration with the domain experts. Finally, we present the results of three evaluation rounds, and reect on our collaborative visualization system.

  • 978-1-4503-4149-3
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Teilprojekt TP 3 - Tracking

2016

Angewandte Virtuelle Techniken im Produktentstehungsprozess

Kap. 5 beschreibt die Forschungsthemen zum Schwerpunkt Tracking. Darunter ist das Erfassen der Position und Orientierung von Objekten bzw. des Anwenders im dreidimensionalen Raum zu verstehen. Die Arbeiten bilden damit die Grundlage für darauf aufbauende Funktionen wie beispielsweise die lagekorrekte Einblendung zusätzlicher Informationen oder die intuitive Interaktion durch Gesten. Neben Ansätzen zur Weiterentwicklung der Algorithmen des markerlosen Trackings werden ergänzende Sensoriken wie Wegaufnehmer an Robotern, Inertialsensoriken an Kameras betrachtet. Ein weiterer Ansatz untersucht die Hinzunahme von CAD-Daten zur Verbesserung des bildbasierten Trackings.

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Kühnel, Hannes; Kuijper, Arjan [Prüfer]; Gutbell, Ralf [Betreuer]

Texturizing and Refinement of 3D City Models with Mobile Devices

2016

Darmstadt, TU, Master Thesis, 2016

In this thesis, I investigate the problem of building recognition from images and video streams of mobile devices to texturize and refine an existing 3D city model. These city models have different origins and so different levels of detail. Existing approaches for this problem are analyzed and compared. Since no suitable approach was found, a new one has to be created. Supported by GPS and Gyroscope sensor data there are multiple possibilities to analyze images of the video stream on a 2D and 3D basis. Different ways to extract buildings from images are presented including model refinement. These are based on computer vision technologies such as 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 use of structure from motion algorithms to create point clouds and extract a building from them. Each of the different detectors yields in successful results depending on different properties of a building such as e.g. the presence of adjoining buildings or accuracy of the 3D model. The edge detection modes yield to the highest accuracy, followed by the extraction from point clouds and pure sensor data. Also future work is presented to expand the shown approaches.

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Cordts, Marius; Omran, Mohamed; Ramos, Sebastian; Rehfeld, Timo; Enzweiler, Markus; Benenson, Rodrigo; Franke, Uwe; Roth, Stefan; Schiele, Bernt

The Cityscapes Dataset for Semantic Urban Scene Understanding

2016

29th IEEE Conference on Computer Vision and Pattern Recognition. Proceedings

IEEE Conference on Computer Vision and Pattern Recognition (CVPR) <2016, Las Vegas, Nevada, USA>

Visual understanding of complex urban street scenes is an enabling factor for a wide range of applications. Object detection has benefited enormously from large-scale datasets, especially in the context of deep learning. For semantic urban scene understanding, however, no current dataset adequately captures the complexity of real-world urban scenes. To address this, we introduce Cityscapes, a benchmark suite and large-scale dataset to train and test approaches for pixel-level and instance-level semantic labeling. Cityscapes is comprised of a large, diverse set of stereo video sequences recorded in streets from 50 different cities. 5000 of these images have high quality pixel-level annotations; 20 000 additional images have coarse annotations to enable methods that leverage large volumes of weakly-labeled data. Crucially, our effort exceeds previous attempts in terms of dataset size, annotation richness, scene variability, and complexity. Our accompanying empirical study provides an in-depth analysis of the dataset characteristics, as well as a performance evaluation of several state-of-the-art approaches based on our benchmark.

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Böhm, J.; Bredif, Mathieu; Gierlinger, Thomas; Krämer, Michel; Lindenbergh, R.; Liu, K.; Michel, Frank; Sirmacek, B.

The IQmulus Urban Showcase: Automatic Tree Classification and Identification in Huge Mobile Mapping Point Clouds

2016

XXIII ISPRS Congress Prague 2016, Commission III

International Society for Photogrammetry and Remote Sensing Congress (ISPRS) <23, 2016, Prague, Czech Republic>

The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences
XLI-B3

Current 3D data capturing as implemented on for example airborne or mobile laser scanning systems is able to efficiently sample the surface of a city by billions of unselective points during one working day. What is still difficult is to extract and visualize meaningful information hidden in these point clouds with the same efficiency. This is where the FP7 IQmulus project enters the scene. IQmulus is an interactive facility for processing and visualizing big spatial data. In this study the potential of IQmulus is demonstrated on a laser mobile mapping point cloud of 1 billion points sampling ~ 10 km of street environment in Toulouse, France. After the data is uploaded to the IQmulus Hadoop Distributed File System, a workflow is defined by the user consisting of retiling the data followed by a PCA driven local dimensionality analysis, which runs efficiently on the IQmulus cloud facility using a Spark implementation. Points scattering in 3 directions are clustered in the tree class, and are separated next into individual trees. Five hours of processing at the 12 node computing cluster results in the automatic identification of 4000+ urban trees. Visualization of the results in the IQmulus fat client helps users to appreciate the results, and developers to identify remaining flaws in the processing workflow.

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Sessler, David; Spott, Martin; Nauck, Detlef; Harmer, William; Kohlhammer, Jörn; Bernard, Jürgen

Towards Combining Attribute-Based and Time Series-Based Visual Querying

2016

EuroVis 2016. Eurographics / IEEE Symposium on Visualization 2016: Posters

Eurographics Conference on Visualization (EuroVis) <18, 2016, Groningen, The Netherlands>

We present a concept for the visual-interactive definition of meaningful subsets in data sets comprising multivariate attributes and time series data. Based on a generalization of requirements of a real-world user group, we propose a three-stage approach, combining visual-interactive querying, query filter analysis, and result exploration. The approach includes several design parameters that can easily be adapted in future design studies for alternative applications.

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Loeb, Stacy; Adam, Meike; Tennstedt, Pierre; Huber, Wolfgang; Bernard, Jürgen; Tilki, Derya; Graefen, Markus; Huland, Hartwig; Schlomm, Thorsten

Toxicity in a multimodality approach of radical prostatectomy with radiation and hormonal therapy

2016

Journal of Clinical Oncology

Genitourinary Cancers Symposium < 2016, San Francisco, CA>

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Trichromatic Reflectance Capture Using a Tunable Light Source: Setup, Characterization and Reflectance Estimation

2016

Measuring, Modeling, and Reproducing Material Appearance 2016

Measuring, Modeling, and Reproducing Material Appearance (MMRMA) <2016, San Francisco, CA, USA>

Electronic Imaging
9

A research project is underway to develop a gonio imager particularly dedicated to sample the Bidirectional Reflectance Distribution Function (BRDF) of materials and material compositions employed and created by multimaterial 3D printers. It comprises an almost colorimetric RGB camera and a spectrally tunable light source. In this paper, we investigate an important part of this system, particularly the approach to estimate reflectances from RGB values acquired under multiple illuminants. We first characterize the system by estimating the spectral sensitivities of the camera. Then, we use the sensitivities, a set of illuminants produced by the tunable light source and the corresponding sensor responses to estimate reflectances. For evaluating this approach, we measure the Neugebauer primary reflectances of a polyjet printer employing highly translucent photo-polymer printing materials colored in cyan, magenta, yellow and white. Spectral and colorimetric deviations to spectroradiometric comparison measurements (average 0.67 CIEDE2000 units / 0.0286 spectral RMS) are within the inter-instrument variability of hand-held spectrophotometers used in graphic arts for prints on paper.

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Huynh, Ngoc Anh; Ng, Wee Keong; Ulmer, Alex; Kohlhammer, Jörn

Uncovering Periodic Network Signals of Cyber Attacks

2016

VizSec 2016

IEEE Symposium on Visualization for Cyber Security (VizSec) <2016, Baltimore, MD, USA>

This paper addresses the problem of detecting the presence of malware that leave periodic traces in network traffic. This characteristic behavior of malware was found to be surprisingly prevalent in a parallel study. To this end, we propose a visual analytics solution that supports both automatic detection and manual inspection of periodic signals hidden in network traffic. The detected periodic signals are visually verified in an overview using a circular graph and two stacked histograms as well as in detail using deep packet inspection. Our approach offers the capability to detect complex periodic patterns, but avoids the unverifiability issue often encountered in related work. The periodicity assumption imposed on malware behavior is a relatively weak assumption, but initial evaluations with a simulated scenario as well as a publicly available network capture demonstrate its applicability.

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Cui, Jian; Kuijper, Arjan; Fellner, Dieter W.; Sourin, Alexei

Understanding People's Mental Models of Mid-Air Interaction for Virtual Assembly and Shape Modeling

2016

Proceedings of the 29th International Conference on Computer Animation and Social Agents

International Conference on Computer Animation and Social Agents (CASA) <29, 2016, Geneva, Switzerland>

Naturalness of the mid-air interaction interface for virtual assembly and shape modeling is important. In order to design an interface perceived as "natural" by most people, common behaviors and mental patterns for mid-air interaction of people have to be recognized, which is an area merely explored yet. This paper serves this purpose of understanding the users' mental interaction models, in order to provide standards and recommendation for devising a natural virtual interaction interface. We tested three kinds of tasks - manipulating tasks, deforming tasks and tool-based operating tasks on 16 participants. We have found that: 1) different features of mental models were observed for different types of tasks. Interaction techniques should be designed to match these features; 2) virtual hand selfavatar helps estimate size of virtual objects, as well as helps plan and visualize the complex process and procedures of a task, which is especially helpful for tool-based tasks; 3) bimanual interaction is witnessed as a dominant interaction mode preferred by the majority; 4) natural gestures for deforming tasks always reflect forces exerted. These suggestions are useful for designing a midair interaction interface matching users' mental models.

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Underwater Visual Computing: The Grand Challenge Just around the Corner

2016

IEEE Computer Graphics and Applications
Graphically Speaking

Visual computing is influencing nearly every aspect of our lives. We plan our new kitchens with augmented reality, rely on camera-based assistance systems in modern cars, and profit from enormous progress in medical imaging technologies for diagnosis. Our smartphones gives us megapixel cameras and high resolution displays available at our fingertips, and the next generation of devices will also offer optical 3D sensors and 3D displays. Via Wi-Fi and 4G networks, we have permanent and affordable broadband access to unlimited data spaces and computing power in the cloud. Global Navigation Satellite Systems (GNSS) even allow us to always accurately determine our positions. All those technologies open up a universe of interactive visual computing applications in every situation and everywhere around the world, right? Not really. Two-thirds of our planet is covered by water. As soon as we leave the land and dive into the oceans, we enter a completely new environment that presents significant differences compared with dry land: - Almost none of the technical devices we use can operate under water. - The optical properties of water strongly influence image acquisition and visualization. - The water damping disconnects users and devices from satellite signals and other wireless network connections. With the growing number of subsea and offshore activities, the research on visual computing applications for underwater settings will become more important in the near future. Many tasks, ranging from marine research to submarine cable inspection, have to be performed underwater and would thus pro_ t from visual computing technology to make them more efficient, robust, and safe. Because of the specific environmental conditions inherent in underwater settings, these applications are not as straightforward as graphical applications in air, which raises many research questions. This article examines some of the challenges for underwater visual computing and looks at the steps being taken to cope with them.

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Unsichtbare Erkennung menschlicher Aktivitäten in Smart Living Umgebungen mit Kapazitiven Sensoren

2016

Zukunft Lebensräume 2016

Zukunft Lebensräume <2016, Frankfurt/Main, Germany>

Smart Living Umgebungen versuchen ihre Bewohner bei der Bewältigung alltäglicher Aufgaben zu unterstützen. Wünsche und Notwendigkeiten werden dynamisch erkannt und eine angemessene Reaktion erzeugt. Dies benötigt mehrere Sensoren, deren Daten intelligent kombiniert werden, um eine Vielzahl von Situationen zu erkennen. Häufig greift man hierbei auf Kameras und Bewegungsmelder zurück, die sich nur schwer unsichtbar in der Umgebung anbringen lassen. Kapazitive Sensoren messen Änderungen in elektrischen Feldern und können durch nicht-leitende Materialien hindurch Messungen vornehmen. In den letzten Jahren stieg ihre Popularität in Forschung und am Markt; insbesondere der fingerkontrollierte Touchscreen ist ein populäres Beispiel. In dieser Arbeit führen wir diese Art von Sensorik ein und stellen vor, inwiefern mit diesen menschliche Aktivitäten in Smart Living Umgebungen gemessen werden können. Wir stellen verschiedene Anwendungen in den Bereichen der Aktivitätserkennung und Mensch-Maschine-Interaktion vor, diskutieren Möglichkeiten und Herausforderungen der kapazitiven Sensorik und stellen zukünftige Forschungsrichtungen vor.

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Using Trajectories Derived by Dense Optical Flows as a Spatial Component in Background Subtraction

2016

WSCG 2016. Full Papers Proceedings

International Conference in Central Europe on Computer Graphics, Visualization and Computer Vision (WSCG) <24, 2016, Plzen, Czech Republic>

Foreground-Background Segregation has been intensively researched in the last decades as it is an important first step in many Computer Vision tasks. Nonetheless, there are still many open questions in this area and in this paper we focus on a special surveillance scenario where a static camera monitors a predefined region. This restrain makes some aspects easier and good results could be achieved with Background Subtraction methods. However, these only work pixelwise and lack the spatial component completely. We suggest an approach to add the crucial spatial information to the segmentations with Dense Optical Flows. For this, a number of successive images are taken from the video to compute the Trajectories of the pixels through these frames. This enables us to fuse the information from the several images and use this for segmentation. The algorithm was evaluated on a video from a surveillance camera and showed promising results.

  • 978-80-86943-57-2
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Berndt, René; Silva, Nelson; Caldera, Christian; Krispel, Ulrich; Eggeling, Eva; Sunk, Alexander; Reisinger, Gerhard; Sihn, Wilfried; Fellner, Dieter W.

VASCO - Digging the Dead Man's Chest of Value Streams

2016

International Journal on Advances in Intelligent Systems

Value stream mapping is a lean management method for analyzing and optimizing a series of events for production or services. Even today the first step in value stream analysis - the acquisition of the current state map - is still created using pen & paper by physically visiting the production line. We capture a digital representation of how manufacturing processes look like in reality. The manufacturing processes can be represented and efficiently analyzed for future production planning as a future state map by using a meta description together with a dependency graph. With VASCO we present a tool, which contributes to all parts of value stream analysis - from data acquisition, over analyzing, planning, comparison up to simulation of alternative future state maps. We call this a holistic approach for Value stream mapping including detailed analysis of lead time, productivity, space, distance, material disposal, energy and carbon dioxide equivalents - depending in a change of calculated direct product costs.

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Berndt, René; Silva, Nelson; Caldera, Christian; Krispel, Ulrich; Eggeling, Eva; Sunk, Alexander; Edtmayr, Thomas; Sihn, Wilfried; Fellner, Dieter W.

VASCO - Mastering the Shoals of Value Stream Mapping

2016

CONTENT 2016

International Conference on Creative Content Technologies (CONTENT) <8, 2016, Rome, Italy>

Value stream mapping is a lean management method for analyzing and optimizing a series of events for production or services. Even today the first step in value stream analysis - the acquisition of the current state - is still created using pen & paper by physically visiting the production place. We capture a digital representation of how manufacturing processes look like in reality. The manufacturing processes can be represented and efficiently analyzed for future production planning by using a meta description together with a dependency graph. With our Value Stream Creator and explOrer (VASCO) we present a tool, which contributes to all parts of value stream analysis - from data acquisition, over planning, comparison with previous realities, up to simulation of future possible states.

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Siegmund, Dirk; Wainakh, Aidmar; Braun, Andreas

Verification of Single-Person Access in a Mantrap Portal Using RGB-D Images

2016

XII Workshop de Visão Computacional. Proceedings

Workshop de Visão Computacional <2016, Campo Grande, Brasil>

Automatic entrance systems are increasingly gaining importance to guarantee security in e.g. critical infrastructure. A pipeline is presented which verifies that only a single, authorized subject can enter a secured area. Verification scenarios are carried out by using a set of RGB-D images. Features, invariant to rotation and pose are used and classified by different metrics to be applied in real-time. The performance was evaluated by using scenarios in which the system was attacked by a second subject. The results show that the presented approach outerperforms competitive methods. It concludes with a summary of strengths and weaknesses and gives an outlook for future work.

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Siegmund, Dirk; Handtke, David; Kähm, Olga

Verifying Isolation in a Mantrap Portal via Thermal Imaging

2016

IWSSIP 2016. Proceedings

International Conference on Systems, Signals and Image Processing (IWSSIP) <23, 2016, Bratislava, Slovakia>

This work presents a system that can be used to ensure that only one individual can pass through a designated transit area (mantrap portal). The developed technical approach uses thermal images to detect humans based on their body heat. A special focus was on the behaviour of the system placed under attack when an intruder tries to overcome the system. The performance was evaluated in empirical testing with a test group, selected according to their physical characteristics. The test scenarios cover changing appearances of individuals and possibly carried objects into the mantrap. Receiver Operating Characteristics (ROC) curves show how the developed system performs. This work concludes with a discussion about a number of challenges and gives an outlook for possible solutions.

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Hund, Michael; Böhm, Dominic; Sturm, Werner; Sedlmair, Michael; Schreck, Tobias; Ullrich, Torsten; Keim, Daniel A.; Majnaric, Ljiljana; Holzinger, Andreas

Visual Analytics for Concept Exploration in Subspaces of Patient Groups

2016

Brain Informatics

Medical doctors and researchers in bio-medicine are increasingly confronted with complex patient data, posing new and difficult analysis challenges. These data are often comprising high-dimensional descriptions of patient conditions and measurements on the success of certain therapies. An important analysis question in such data is to compare and correlate patient conditions and therapy results along with combinations of dimensions. As the number of dimensions is often very large, one needs to map them to a smaller number of relevant dimensions to be more amenable for expert analysis. This is because irrelevant, redundant, and conflicting dimensions can negatively affect effectiveness and efficiency of the analytic process (the so-called curse of dimensionality). However, the possible mappings from high- to low-dimensional spaces are ambiguous. For example, the similarity between patients may change by considering different combinations of relevant dimensions (subspaces). We demonstrate the potential of subspace analysis for the interpretation of high-dimensional medical data. Specifically, we present SubVIS, an interactive tool to visually explore subspace clusters from different perspectives, introduce a novel analysis workflow, and discuss future directions for high-dimensional (medical) data analysis and its visual exploration. We apply the presented workflow to a real-world dataset from the medical domain and show its usefulness with a domain expert evaluation.

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Silva, Nelson; Shao, Lin; Schreck, Tobias; Eggeling, Eva; Fellner, Dieter W.

Visual Exploration of Hierarchical Data Using Degree-of-Interest Controlled by Eye-Tracking

2016

FMT 2016

Forum Media Technology (FMT) <9, 2016, St. Pölten, Austria>

Effective visual exploration of large data sets is an important problem. A standard technique for mapping large data sets is to use hierarchical data representations (trees, or dendrograms) that users may navigate. If the data sets get large, so do the hierarchies, and effective methods for the navigation are required. Traditionally, users navigate visual representations using desktop interaction modalities, including mouse interaction. Motivated by recent availability of lowcost eye-tracker systems, we investigate application possibilities to use eye-tracking for controlling the visual-interactive data exploration process. We implemented a proof-of-concept system for visual exploration of hierarchic data, exemplified by scatter plot diagrams which are to be explored for grouping and similarity relationships. The exploration includes usage of degree-of-interest based distortion controlled by user attention read from eye-movement behavior. We present the basic elements of our system, and give an illustrative use case discussion, outlining the application possibilities. We also identify interesting future developments based on the given data views and captured eye-tracking information.

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Vu, Bui Minh; Urban, Philipp; Tanksale, Tejas Madan; Nakauchi, Shigeki

Visual Perception of 3D Printed Translucent Objects

2016

24th Color and Imaging Conference

Color Imaging Conference (CIC) <24, 2016, San Diego, CA, USA>

In order to reproduce translucent objects by 3D printers employing fully transparent (or clear) material, modeling the human visual perception of translucency is crucial. In this preliminary study, a set of 256 texture-less samples was created by mixing white and clear materials using multi-jet 3D printing. The samples differ in both lateral light transport properties and transmittance. Two psychophysical experiments were conducted to reveal the relationship between transmittance and a perceptually uniform scale for translucency. The results show that Stevens' power law describes well this relationship within the optically thin range of samples. Furthermore, the sensitivity to lateral light transport is small compared to transmittance for the texture-less sample set.

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Lakhani, Vishal; Kuijper, Arjan [Gutachter]; Ruppert, Tobias [Betreuer]

Visual-Interactive Document Classification

2016

Darmstadt, TU, Master Thesis, 2016

In recent years, textual data are stored in a web or document format. These data are stored in an unstructured manner. In Organizing these data in some structured format would help exploiting these information in many applications. However, this task or organizing requires lots of time and human efforts. The Machine can help user to organize these data. User can define some labels and manually assign some documents to these classes. With these manually assigned documents, the machine can build a model that will automatically classify rest of the documents, which have not been labeled by the user. Though machine also requires some human effort to assign label to some documents based on which it can decide to classify rest of the documents. Again, this task requires lots of human effort and it is time consuming too, as human requires some time to manually assign label to documents. The problem is how to get good classification result with less human effort or in other words, in a situation where the user is only required to assign label to only few documents. So, in this thesis, an application is built with user interface to provide the results to the user in an interactive manner. The application takes some input from the user, build a model and then presents results using visualization techniques. Along with the results, suggestions are also provided to the user for the next iteration to build more accurate classifier. A process called Active Learning helps user to build more accurate model. Active learning is a process in which a classifier will interactively query the user to get some desired results on new samples. Active Learning helps users to pick up the most informative sample/document for classification. It provides suggestions to the user to select best document for training. In this thesis, an approach for classifying documents using user's feedback is introduced. Classification results will be provided to the users in an visualization manner. For the next iterations, users are presented with suggestions to pick up the most informative document. This task is done using Active Learning approach. By using the suggestions, user can give his own feedback and help the classifier to build a model which is more accurate. These suggestions are provided to the user in visualization manner. Users will be provided confidence score and colors of the desired class in Graphical User Interface(GUI). Thus, user can easily select the next document as suggested by the model. In this way, overall performance of the classifier will be improved. The model is evaluated using visualization of results; and using some results of consecutive iterations, more accurate model was achieved.

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Bernard, Jürgen; Sessler, David; Steiger, Martin; Spott, Martin; Kohlhammer, Jörn

Visual-Interactive Exploration of Relations Between Time-Oriented Data and Multivariate Data

2016

EuroVA 2016

International EuroVis Workshop on Visual Analytics (EuroVA) <7, 2016, Groningen, The Netherlands>

The analysis of large, multivariate data sets is challenging, especially when some of these data objects are timeoriented. Exploring relationships between multivariate and temporal information, e.g., to identify patterns that support decision making is an important industrial analysis task. The target group of this design study are data analysts aiming at detecting fault patterns in a telecommunications network in order to spend maintenance budget more effectively. We present a visual analytics tool that provides overviews of multivariate data sets and associated time series. Users can select data subsets of interest in both attribute data and clustered time series data. Linked views consequently support the identification of relations between the two spaces. To ensure usefulness, the tool was designed in an iterative way, based on a careful characterization of the data, users, and tasks. A usage scenario demonstrates the applicability of the approach.

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Shao, Lin; Sacha, Dominik; Neldner, Benjamin; Stein, Manuel; Schreck, Tobias

Visual-Interactive Search for Soccer Trajectories to Identify Interesting Game Situations

2016

Visualization and Data Analysis 2016

Visualization and Data Analysis (VDA) <2016, San Francisco, CA, USA>

Electronic Imaging
1

Recently, sports analytics has turned into an important research area of visual analytics and may provide interesting findings, such as the best player of the season, for various kinds of sports. Soccer is a very popular and tactical game, which also attracted great attention in the last few years. However, the search for complex game movements is a very crucial and challenging task. We present a system for searching trajectory data in soccer matches by means of an interactive search interface that enables the user to sketch a situation of interest. Furthermore, we apply a domain specific prefiltering process to extract a set of local movement segments, which are similar to a given sketch. Our approach comprises single-trajectory, multi-trajectory, and event-specific search functions based on two different similarity measures. To demonstrate the usefulness of our approach, we define a domain specific task analysis and conduct a case study together with a domain expert from FC Bayern München by investigating a real-world soccer match. Finally, we show that multi-trajectory search in combination with event-specific filtering is needed to describe and retrieve complex moves in soccer matches.

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Bernard, Jürgen; Dobermann, Eduard; Bögl, Markus; Röhlig, Martin; Vögele, Anna; Kohlhammer, Jörn

Visual-Interactive Segmentation of Multivariate Time Series

2016

EuroVA 2016

International EuroVis Workshop on Visual Analytics (EuroVA) <7, 2016, Groningen, The Netherlands>

Choosing appropriate time series segmentation algorithms and relevant parameter values is a challenging problem. In order to choose meaningful candidates it is important that different segmentation results are comparable. We propose a Visual Analytics (VA) approach to address these challenges in the scope of human motion capture data, a special type of multivariate time series data. In our prototype, users can interactively select from a rich set of segmentation algorithm candidates. In an overview visualization, the results of these segmentations can be compared and adjusted with regard to visualizations of raw data. A similarity-preserving colormap further facilitates visual comparison and labeling of segments. We present our prototype and demonstrate how it can ease the choice of winning candidates from a set of results for the segmentation of human motion capture data.

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Niese, Christoph; Landesberger, Tatiana von; Kuijper, Arjan

Visualization of Composer Relationships Using Implicit Data Graphs

2016

Human Interface and the Management of Information: Applications and Services

International Conference on Human Interface and the Management of Information (HIMI) <2016, Toronto, ON, Canada>

Relationships between classical music composers are known due to explicit historic material, for instance the friendship between Joseph Haydn and Wolfgang Amadeus Mozart, as well as the influence of the latter on Ludwig van Beethoven. While Haydn and Mozart were critics of each others work, Mozart and Beethoven probably never met in person. In spite of that there is an impact on especially the early music of Beethoven. While relationships between well-known composers like the mentioned ones are investigated, it can also be of historic interest to know the roles less-known composers played. Some of them might have a part in a famous persons work but were not further analyzed given the fact that there have been many composers and no hints given to researchers indicating which person would be worth studying. In this work we develop an approach to visually hint possible relationships among a large number of composers. Detailed historic knowledge is not taken into account; the hints are only based on the composer works as well as their lifetimes in order to guess directions of influence.

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Beuth, Marcel; Kuijper, Arjan [1. Gutachten]; May, Thorsten [2. Gutachten]

Visualization of General Graphs with Metro Maps

2016

Darmstadt, TU, Bachelor Thesis, 2016

In this work an algorithm is developed that generates a Metro Map layout for general graphs that is not based on a geographical background. Metro Maps have the great advantage of good and intuitive readability. The developed algorithm is based on the work of Stott et al. The special feature in this work is that the visualized graph is a partial graph of a more complex graph. This embedding has influence to the visualization of the Metro Map.

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Landesberger, Tatiana von; Fellner, Dieter W.; Ruddle, Roy A.

Visualization System Requirements for Data Processing Pipeline Design and Optimization

2016

IEEE Transactions on Visualization and Computer Graphics

Eurographics Conference on Visualization (EuroVis) <19, 2017, Barcelona, Spain>

The rising quantity and complexity of data creates a need to design and optimize data processing pipelines - the set of data processing steps, parameters and algorithms that perform operations on the data. Visualization can support this process but, although there are many examples of systems for visual parameter analysis, there remains a need to systematically assess users' requirements and match those requirements to exemplar visualization methods. This article presents a new characterization of the requirements for pipeline design and optimization. This characterization is based on both a review of the literature and first-hand assessment of eight application case studies. We also match these requirements with exemplar functionality provided by existing visualization tools. Thus, we provide end-users and visualization developers with a way of identifying functionality that addresses data processing problems in an application. We also identify seven future challenges for visualization research that are not met by the capabilities of today's systems.

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Staab, Michael Markus; Kuijper, Arjan [Gutachter]; Ruppert, Tobias [Betreuer]

Visuell-Interaktive Exploration von Text Clustering Ergebnissen

2016

Darmstadt, TU, Master Thesis, 2016

Digital vorliegende Texte gewinnen immer mehr an Bedeutung und sind gleichzeitig in ihrer Vielzahl und Komplexität für einen Leser nur schwer zu durchschauen. Clustering-Verfahren können hier hilfreich sein: Sie unterstützen den Anwender dabei, Text auf Basis des enthaltenen Inhalts zu gruppieren. Allerdings bestehen dabei viele Abhängigkeiten, die zu potenziell sehr diversen Ergebnissen führen, wobei es immer vom konkreten Einzelfall abhängt, welches Ergebnis als "das beste" anzusehen ist. Deswegen ist es sowohl sinnvoll, mehrere Clusterings mit unterschiedlichen Parametern durchzuführen und zu vergleichen, als auch, den Benutzer aktiv in den Analyseprozess miteinzubeziehen. Ziel dieser Arbeit war es, ein Textclustering-System zu entwickeln, das in der Lage ist, Clusterings mit direkter Interaktion des Benutzers zu erstellen, zu analysieren und zu vergleichen. Hierfür wurde sowohl eine neuartige Version der Featureselektion implementiert als auch sehr viel Wert auf die Visualisierung der einzelnen Prozessabläufe gelegt. Eine anschließende Auswertung kam zu dem Ergebnis, dass die Featureselektion gut funktioniert und die Nützlichkeit des Systems gegeben ist. Für die Zukunft bietet es sich an, die Verfahren im System noch zu erweitern und dem Benutzer die Möglichkeit zu geben, selbst weitere Qualitätsmetriken und Verfahren einzupflegen.

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Was Deutschland für den Erhalt von Kulturerbe in Syrien tun kann

2016

Restauro

Um Verluste zu minimieren, wurden bereits zahlreiche Maßnahmen zum Kulturguterhalt in Syrien getroffen. Einen ersten Ansatz liefert das Projektvorhaben We-SyCURE, das derzeit von Präventionsingenieure e. V. ausgearbeitet wird.

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Klamet, Josephin; Matthies, Denys J.C.; Minge, Michael

WeaRelaxAble: A Wearable System to Enhance Stress Resistance using Various Kinds of Feedback Stimuli

2016

iWOAR 2016

International Workshop on Sensor-based Activity Recognition (iWOAR) <3, 2016, Rostock, Germany>

This paper introduces a wearable feedback device that aims at relaxing the user in stressful situations. The system, which is called WeaRelaxAble, provides various feedback modalities, such as vibration, ambient light, acoustic stimuli and heat in order to reduce the user's stress level. The development of WeaRelaxAble is based on two studies: At first, all five kinds of feedback and appropriate body positions for stimulation were evaluated with 15 participants. Based on the findings of this initial study, we built a wearable Arduino prototype to prove the feasibility of our concept. The experience while using the system was tested with 26 test subjects under laboratory conditions. We conclude with a concept design of a wrist-worn device that provides acoustic and visual feedback. As tactile stimulation, a shirt would provide vibration at the positions of the shoulders as well as heat at the loins. Users can explicitly activate the system at any time and in any combination of feedback modalities.

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Ma, Jingting; Lin, Feng; Honsdorf, Jonas; Lentzen, Katharina; Wesarg, Stefan; Erdt, Marius

Weighted Robust PCA for Statistical Shape Modeling

2016

Medical Imaging and Augmented Reality

International Conference on Medical Imaging and Augmented Reality (MIAR) <7, 2016, Bern, Switzerland>

Statistical shape models (SSMs) play an important role in medical image analysis. A sufficiently large number of high quality datasets is needed in order to create a SSM containing all possible shape variations. However, the available datasets may contain corrupted or missing data due to the fact that clinical images are often captured incompletely or contain artifacts. In this work, we propose a weighted Robust Principal Component Analysis (WRPCA) method to create SSMs from incomplete or corrupted datasets. In particular, we introduce a weighting scheme into the conventional Robust Principal Component Analysis (RPCA) algorithm in order to discriminate unusable data from meaningful ones in the decomposition of the training data matrix more accurately. For evaluation, the proposed WRPCA is compared with conventional RPCA on both corrupted (63 CT datasets of the liver) and incomplete datasets (15 MRI datasets of the human foot). The results show a significant improvement in terms of reconstruction accuracy on both datasets.

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Werker der Zukunft: Assistenz im Zeitalter von Industrie 4.0

2016

VDE-Kongress 2016 - Internet der Dinge

VDE-Kongress <2016, Mannheim>

Mit der vierten industriellen Revolution wandelt sich die Produktion. Fertigungsumgebungen werden komplexer und viele Prozesse funktionieren automatisiert. Das erfordert eine nahtlose und flexible Einbindung des Menschen in die digitale Fertigung. Insbesondere in der manuellen Montage führt die steigende Variantenvielfalt zu einer Komplexität, die sich nur noch durch die Unterstützung technischer Assistenzsysteme sicher beherrschen lässt. Der Beitrag stellt die Herausforderungen komplexer manueller Montage- und Wartungsprozesse vor, um darauf aufbauend eine Vision für den Werker der Zukunft zu entwerfen. Diese Vision wird anschließend mit zwei Lösungsansätzen aus der Fraunhofer-Forschung illustriert.

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Zur Rolle des Menschen in der Zukunftsvision Maritim 4.0

2016

Schiff & Hafen

Die Digitalisierung bietet große Potenziale zur Optimierung von Produkten und Prozessen der maritimen Branche. Der Beitrag betrachtet anhand konkreter Anwendungsbeispiele, welche Auswirkungen diese Änderungen für die Mitarbeiter in der Produktion, aber auch beim Schiffsbetrieb haben werden. Dazu wird einleitend aufgezeigt, wie Technologien des Visual Computing genutzt werden können, um die zunehmende Komplexität digital vernetzter Umgebungen für den Menschen beherrschbar zu machen.