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

2014

Estevez, Elsa (Ed.) et al.: ICEGOV 2014 : Proceedings of the 8th International Conference on Theory and Practice of Electronic Governance. New York: ACM Press, 2014, pp. 399-402

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

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

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

Constructive Roof Geometry

2014

2014 International Conference on Cyberworlds : CW 2014. Los Alamitos, Calif.: IEEE Computer Society Conference Publishing Services (CPS), 2014, pp. 63-70

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

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

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

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

2014

Klein, Reinhard (Ed.) et al.: GCH 2014. Short Papers - Posters : Eurographics Workshop on Graphics and Cultural Heritage. Goslar: Eurographics Association, 2014, pp. 10-12

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

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

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

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

2014

Battiato, Sebastiano (Ed.) et al.: VISAPP 2014 - Volume I : Proceedings of the International Conference on Computer Vision Theory and Applications. SciTePress, 2014, pp. 417-424

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

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

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

2014

2014 IEEE/ACM 7th International Conference on Utility and Cloud Computing : UCC 2014. Los Alamitos, Calif.: IEEE Computer Society, 2014, pp. 824-829

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

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

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Converting Underwater Imaging into Imaging in Air

2014

Battiato, Sebastiano (Ed.) et al.: VISAPP 2014 - Volume I : Proceedings of the International Conference on Computer Vision Theory and Applications. SciTePress, 2014, pp. 96-103

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

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

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

Core Technologies for the Internet of Services

2014

Wahlster, Wolfgang (Ed.) et al.: Towards the Internet of Services: The THESEUS Research Program. Berlin, Heidelberg, New York: Springer, 2014. (Cognitive Technologies), pp. 59-88

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

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

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

2014

Linguraru, Marius George (Ed.) et al.: Clinical Image-Based Procedures. Translational Research in Medical Imaging : Third International Workshop, CLIP 2014. Held in Conjunction with MICCAI 2014. Berlin, Heidelberg, New York: Springer, 2014. (Lecture Notes in Computer Science (LNCS) 8680), pp. 25-32

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

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

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

CultLab3D - On the Verge of 3D Mass Digitization

2014

Klein, Reinhard (Ed.) et al.: GCH 2014 : Eurographics Workshop on Graphics and Cultural Heritage. Goslar: Eurographics Association, 2014, pp. 65-73

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

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

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

2014

Bienert, Andreas (Ed.) et al.: EVA 2014 Berlin. Proceedings : Elektronische Medien & Kunst, Kultur, Historie. Berlin: Gesellschaft zur Förderung angewandter Informatik e.V., 2014, pp. 106-109

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

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

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Zander-Walz, Sebastian; Kuijper, Arjan (Betreuer); Braun, Andreas (Betreuer)

Curved Large-Area Surfaces for Gestural Interaction

2014

Darmstadt, TU, Bachelor Thesis, 2014

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

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

Demo Hour

2014

Interactions, Vol.21 (2014), 5, pp.6-9

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

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

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Wang, Anqi; Sakas, Georgios (Betreuer); Noll, Matthias (Betreuer)

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

2014

Darmstadt, TU, Master Thesis, 2014

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

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Deterministic Local Layouts through High-Dimensional Layout Stitching

2014

Kurosu, Masaaki (Ed.): Human-Computer Interaction: Part 1 : Theories, Methods, and Tools. HCI International 2014. Berlin, Heidelberg, New York: Springer, 2014. (Lecture Notes in Computer Science (LNCS) 8510), pp. 643-651

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

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

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Die mobile Digitalisierstraße CultLab3D

2014

KulturBetrieb, (2014), 4, pp. 60-61

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

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Die Temperierung. Beiträge zum aktuellen Forschungsstand: Tagungsband zum Internationalen Kolloquium im Kloster Benediktbeuern am 12. November 2012

2014

Schriftenreihe des Bayerischen Landesamtes für Denkmalpflege 8

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

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Schwertel, Uta; Diener, Holger; Heinitz, Antje; Schäfer, Markus; Schlemminger, Andreas

Digitale Bildungsdienste für Elektromobilität - Beispiele aus dem Projekt MEMO

2014

IM+io, (2014), Special 01, pp. 66-72

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

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

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

2014

Radiology, Vol.271 (2014), 3, pp. 778-784

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

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Gennies, Maria; Urban, Bodo (Betreuer); Gutzeit, Enrico (Betreuer); Zhou, Zhiliang (Betreuer)

Echtzeit-Gesichtsdetektion und -verschleierung in Videos unter praktischen Bedingungen

2014

Magdeburg, Univ., Diplomarbeit, 2014

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

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

Efficient Heuristic Adaptive Quadrature on GPUs: Design and Evaluation

2014

Wyrzykowski, Roman (Ed.) et al.: Parallel Processing and Applied Mathematics : 10th International Conference 2013. Revised Selected Papers, Part I. Berlin, Heidelberg, New York: Springer, 2014. (Lecture Notes in Computer Science (LNCS) 8384), pp. 652-662

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

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

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Schiffer, Thomas; Fellner, Dieter W.

Efficient Multi-kernel Ray Tracing for GPUs

2014

Coquillart, Sabine (Ed.) et al.: GRAPP 2014 : Proceedings of the International Conference on Computer Graphics Theory and Applications and International Conference on Information Visualization Theory and Applications. SciTePress, 2014, pp. 209-217

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

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

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

2014

Bender, Jan (Ed.) et al.: VMV 2014 : Vision, Modeling, and Visualization. Goslar: Eurographics Association, 2014, pp.159-166

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

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

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Schönfelder, Tom; Urban, Bodo (Betreuer); Aehnelt, Mario (Betreuer)

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

2014

Rostock, Univ., Studienarbeit, 2014

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

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Enhanced Shadow Detection for 3D Ultrasound

2014

Deserno, Thomas Martin (Ed.) et al.: Bildverarbeitung für die Medizin 2014 : Algorithmen, Systeme, Anwendungen. Proceedings des Workshops. Berlin, Heidelberg, New York: Springer, 2014. (Informatik aktuell), pp. 234-239

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

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

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

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

2014

Iliadis, Lazaros (Ed.) et al.: Artificial Intelligence Applications and Innovations : AIAI 2014 Workshops: CoPA, MHDW, IIVC, and MT4BD. Berlin, Heidelberg, New York: Springer, 2014. (IFIP Advances in Information and Communication Technology 437), pp. 330-339

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

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