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International Research and Training Group 1131 Workshop on visualization of Large and Unstructured data Sets: Applications in Geospatial Planning, Modeling and Engineering, VLUDS 2011

作者： Hlawitschka, Mark W. Chen, Fang Bart, Hans-Jörg Hamann, Bernd Department of Separation Science and Technology University of Kaiserslautern Germany Computer Graphics and HCI Group University of Kaiserslautern Germany CS Department Institute for Data Analysis and Visualization University of California Davis United States 2 University of Kaiserslautern Germany

ISBN: (纸本)9783939897460

In this joint work, a complete framework for modeling, simulating and visualizing multiphase fluid flow within an extraction column is presented. We first present a volume-of-fluid simulation, which is able to predict the surface of the droplets during coalescence. However, a fast and efficient model is needed for the simulation of a liquid-liquid extraction column due to the high number of occurring droplets. To simulate the velocity and droplet size in a DN32 extraction column, a coupled computational fluid dynamic-population balance model solver is used. The simulation is analyzed using path-line based visualization techniques. A novel semi-automatic re-seeding technique for droplet path-line integration is proposed. With our technique, path-lines of fluid droplets can be re-initialized after contact with the stirring devices. The droplet breakage is captured, allowing the engineer to improve the design of liquid-liquid columns layout.

关键词： Computational fluid dynamics

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Geometry-preserving topological landscapes

Geometry-preserving topological landscapes

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Workshop at SIGGRAPH Asia 2012, WASA 2012

作者： Beketayev, Kenes Weber, Gunther H. Morozov, Dmitriy Abzhanov, Aidos Hamann, Bernd Computational Research Division Lawrence Berkeley National Laboratory United States Institute for Data Analysis and Visualization Computer Science Department University of California Davis CA United States Computer Science Department Center for Energy Research Nazarbayev University Kazakhstan

ISBN: (纸本)9781450318358

We propose a novel technique for building geometry-preserving topological landscapes. Our technique creates a direct correlation between a scalar function and its topological landscape. This correlation is accomplished by introducing the notion of geometric proximity into the topological landscapes, reflecting the distance of topological features within the function domain. Furthermore, this technique enables direct comparative analysis between scalar functions, as long as they are defined on the same domain. We describe a construction technique that consists of three stages: contour tree computation, contour tree layout, and landscape construction. We provide a detailed description for the latter two steps. For the contour tree layout stage, we discuss dimension reduction and edge routing techniques that produce a drawing of the contour tree on the plane that preserves the geometric proximity. For the landscape construction stage, we develop a contour construction algorithm that takes the contour tree layout as an input, adds contours at heights that correspond to saddles of the contour tree, and produces a contour map. After an additional triangulation step, this construction method results in the landscape that has the same contour tree as the original function. © 2012 ACM.

关键词： Trees (mathematics)

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Three-dimensional simulations of geometrically complex subduction with large viscosity variations

Three-dimensional simulations of geometrically complex subdu...

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1st Conference of the Extreme Science and Engineering Discovery Environment: Bridging from the eXtreme to the Campus and Beyond, XSEDE12

作者： Jadamec, Margarete A. Billen, Magali I. Kreylos, Oliver Department of Geological Sciences Brown University 324 Brook Street Box 1846 Providence RI 02912 United States Department of Geology University of California Davis One Shields Avenue Davis CA 95616 United States Institute for Data Analysis and Visualization University of California Davis 2306 Academic Surge Building Davis CA 95616 United States

ISBN: (纸本)9781450316026

The incorporation of geologic realism into numerical models of subduction is becoming increasingly necessary as observational and experimental constraints indicate plate boundaries are inherently three-dimensional (3D) in nature and contain large viscosity variations. However, large viscosity variations occurring over short distances pose a challenge for computational codes, and models with complex 3D geometries require substantially greater numbers of elements, increasing the computational demands. We modified a community mantle convection code, CitcomCU, to model realistic subduction zones that use an arbitrarily shaped 3D plate boundary interface and incorporate the effects of a strain-rate dependent viscosity based on an experimentally derived flow law for olivine aggregates. Tests of this implementation on 3D models with a simple subduction zone geometry indicate that limiting the overall viscosity range in the model, as well as limiting the viscosity jump across an element, improves model runtime and convergence behavior, consistent with what has been shown previously. In addition, the choice of method and averaging scheme used to transfer the viscosity structure to the different levels in the multigrid solver can significantly improve model performance. These optimizations can improve model runtime by over 20%. 3D models of a subduction zone with a complex plate boundary geometry were then constructed, containing over 100 million finite element nodes with a local resolution of up to 2.35 km, and run on XSEDE. These complex 3D models, representative of the Alaska subduction zone-transform plate boundary, contain viscosity variations of up to seven orders of magnitude. The optimizations in solver parameters determined from the simple 3D models of subduction applied to the much larger and more complex models of an actual subduction zone improved model convergence behavior and reduced runtimes by on the order of 25%. One scientific result from 3D models of Alaska

关键词： Viscosity

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Collaborative Factory Planning in Virtual Reality

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Procedia CIRP 2012年 3卷 317-322页

作者： N. Menck X. Yang C. Weidig P. Winkes C. Lauer H. Hagen B. Hamann J.C. Aurich Institute for Manufacturing Technology and Production Systems (FBK) 67653 Kaiserslautern Germany Computer Graphics and HCI Group 67653 Kaiserslautern Germany Institute for Data Analysis and Visualization (IDAV) Davis 95616-8562 USA

The competitive development and optimization of manufacturing systems challenge the collaboration and innovation of enterprises. Different information, thinking, and points of view have to be exchanged across engineering, decision-making, and executive levels safely and effectively. The Virtual Reality (VR) technologies provide the users advanced Human-Computer-Interfaces for designing, analyzing, and optimizing complex manufacturing systems. The objective of this paper is to describe a VR-based approach that allows the simultaneous visualization, investigation, and analysis for factory planning. This gives global entities a competitive advantage when conducting business.

关键词： Distance Collaboration Factory Planning Virtual Reality

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Isosurface extraction from hybrid unstructured grids containing pentahedral elements

Isosurface extraction from hybrid unstructured grids contain...

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International Conference on Computer Graphics Theory and Applications, GRAPP 2012 and International Conference on Information visualization Theory and Applications, IVAPP 2012

作者： Narayan, Akshay Sreevalsan-Nair, Jaya Gaither, Kelly Hamann, Bernd International Institute of Information Technology - Bangalore 26/C Electronics City Hosur Road Bangalore 560100 India Texas Advanced Computing Center University of Texas at Austin 10100 Burnet Road Austin TX 78758 United States Institute for Data Analysis and Visualization Department of Computer Science University of California Davis One Shields Avenue Davis CA 95616 United States

ISBN: (纸本)9789898565020

Grid-based computational simulations often use hybrid unstructured grids consisting of various types of elements. Most commonly used elements are tetrahedral, pentahedral (namely, square pyramids and right triangular prisms) and hexahedral elements. Extracting isosurfaces of scalar fields defined on such hybrid unstructured grids is often done using indirect methods, such as, (a) subdividing all non-tetrahedral cells into tetrahedra and computing the triangulated isosurfaces using the marching tetrahedra algorithm, or (b) triangulating intersection points of edges of cells and computing the isosurface using a standard triangulation algorithm. Using the basic ideas underlying the well-established marching cubes and marching tetrahedra algorithms, which are applied to hexahedral and tetrahedral elements, respectively, we generate look-up tables for extracting isosurfaces directly from pentahedral elements. By using appropriate look-up tables, it is possible to process nearly all types of hybrid unstructured grids used in practical applications without the need for indirect methods. We construct look-up tables for square pyramidal and triangular prismatic cells with accurate topological considerations.

关键词： Table lookup

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Topology exploration with hierarchical landscapes

Topology exploration with hierarchical landscapes

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Workshop at SIGGRAPH Asia 2012, WASA 2012

作者： Demir, Dogan Beketayev, Kenes Weber, Gunther H. Bremer, Peer-Timo Pascucci, Valerio Hamann, Bernd Scientific Computing and Imaging Institute School of Computing University of Utah United States Computational Research Divisition Lawrence Berkeley National Laboratory United States Center for Applied Scientific Computing Lawrence Livermore National Laboratory United States Institute for Data Analysis and Visualization Computer Science Department University of California Davis CA United States

ISBN: (纸本)9781450318358

Topological landscapes have been proposed as a visual metaphor for contour trees that does not require an understanding of the theory involved in defining contour trees. The idea is to create a representative terrain with the same topological structure as a given contour tree. This representation exploits the natural human ability to interpret topography and results in an intuitive visualization of otherwise abstract information. However, topological landscapes still suffer from some of the same limitations as traditional contour tree visualization. Most notable is the fact that for complex functions landscapes can quickly become highly complex, exceeding the limits of human comprehension as well as the available computing resources. To address this challenge, we propose a new framework for the dynamic creation and visualization of hierarchical topological landscapes. Our system provides an interactive visualization of complex functions by utilizing a hierarchical decomposition of the contour tree as well as focus+context type interactions. For three dimensional data, we link the landscape display to flexible isosurface extraction in order to correlate terrain features with their corresponding three dimensional counterparts. We demonstrate the utility and versatility of our approach on a variety of both low and high dimensional data sets. © 2012 ACM.

关键词： visualization

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Ultra-high resolution four dimensional geodetic imaging of engineered structures for stability assessment

Ultra-high resolution four dimensional geodetic imaging of e...

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GeoCongress 2012: State of the Art and Practice in Geotechnical Engineering

作者： Bawden, G.W. Bond, S. Podoski, J.H. Kreylos, O. Kellogg, L.H. United States Geological Survey 3020 State University Drive East Modoc Hall Suite 4004 Sacramento CA 95819 United States Corps of Engineers Honolulu District CEPOH-EC-T Building 223 Ft. Shafter HI 96958 United States University of California Davis Institute for Data Analysis and Visualization University of California One Shields Avenue Davis CA 95616 United States University of California Davis Department of Geology University of California One Shields Avenue Davis CA 95616 United States

ISBN: (纸本)9780784412121

We used ground-based Tripod LiDAR (T-LiDAR) to assess the stability of two engineered structures: a bridge spanning the San Andreas fault following the M6.0 Parkfield earthquake in Central California and a newly built coastal breakwater located at the Kauma¯lapa'u Harbor Lana'i, Hawaii. In the 10 weeks following the earthquake, we found that the surface under the bridge shifted 7.1 cm with an additional 2.6 cm of motion in the subsequent 13 weeks, which deflected the bridge's northern I-beam support 4.3 cm and 2.1 respectively;the bridge integrity remained intact. T-LiDAR imagery was collected after the completion of armored breakwater with 817 35-ton interlocking concrete armor units, Core-Locs®, in the summers of 2007, 2008 and 2010. We found a wide range of motion of individual Core-Locs, from a few centimeters to >110 cm along the ocean side of the breakwater, with lesser movement along the harbor side. © 2012 American Society of Civil Engineers.

关键词： Earthquakes

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VirCA NET and CogInfoCom: Novel challenges in future internet based augmented/Virtual Collaboration

VirCA NET and CogInfoCom: Novel challenges in future interne...

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International Conference on Cognitive Infocommunications (CogInfoCom)

作者： Christian Weidig Adam Csapo Jan C. Aurich Bernd Hamann Oliver Kreylos Institute for Manufacturing Technology and Production Systems University of Kaiserslautern Kaiserslautern Germany Computer and Automation Research Institute Budapest Hungary Department of Telecommunications and Media Informatics Budapest University of Technology and Economics Budapest Hungary Institute for Data Analysis and Visualization (IDAV) University of California Davis USA

Several challenges can arise during augmented/virtual collaboration. In this paper, we identify and classify some of these challenges from a cognitive infocommunications (CogInfoCom) point of view. The starting point of our analysis is the VirCA NET application, which was built on the Virtual Collaboration Arena (VirCA) and developed at the MTA SZTAKI. First, we demonstrate how VirCA and VirCA NET belong to the CogInfoCom paradigm and how they are also related to Future Internet. To highlight our ideas in a practical use-case, we identify key features of infocommunication in a collaborative scenario for building industrial production layouts. In the collaborative scenario, factory planning is defined as a multi-stakeholder and multi-domain challenge, which distributed planning teams have to face. Based on the features of VirCA NET and the specifics of the scenario, we outline a list of challenges, some of which are already solved by the system to some extent, and some of which remain to be solved in future work. The challenges are presented in relation to the theoretical background of CogInfoCom engines and CogInfoCom channels, in order to further strengthen the link between augmented/virtual collaboration and the goals of CogInfoCom.

关键词： Collaboration Planning Production facilities Layout Internet Engines Robots

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Abstract: Exploring Performance data with Boxfish

Abstract: Exploring Performance Data with Boxfish

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High Performance Computing, Networking, Storage and analysis (SCC), SC Companion:

作者： Katherine E. Isaacs Aaditya G. Landge Todd Gamblin Peer-Timo Bremer Valerio Pascucci Bernd Hamann Institute for Data Analysis and Visualization Department of Computer Science University of California Davis CA USA Scientific Computing and Imaging Institute University of Utah Salt Lake UT USA Center for Applied Scientific Computing Lawrence Livermore National Laboratories Livermore CA USA

The growth in size and complexity of scaling applications and the systems on which they run pose challenges in analyzing and improving their overall performance. With metrics coming from thousands or millions of processes, visualization techniques are necessary to make sense of the increasing amount of data. To aid the process of exploration and understanding, we announce the initial release of Boxfish, an extensible tool for manipulating and visualizing data pertaining to application behavior. Combining and visually presenting data and knowledge from multiple domains, such as the application's communication patterns and the hardware's network configuration and routing policies, can yield the insight necessary to discover the underlying causes of observed behavior. Boxfish allows users to query, filter and project data across these domains to create interactive, linked visualizations.

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Progressive parallel coordinates

Progressive parallel coordinates

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Pacific (formerly Asia-Pacific APVIS) visualization Symposium

作者： René Rosenbaum Jian Zhi Bernd Hamann Visual Computing and Computer Graphics group (VCG) Institute for Computer Science University of Rostock Rostock Germany Institute for Data Analysis and Visualization (IDAV) Department of Computer Science University of California Davis CA USA Department of Industrial Engineering and Operations Research Columbia University NY USA

Progressive refinement is a methodology that makes it possible to elegantly integrate scalable data compression, access, and presentation into one approach. Specifically, this paper concerns the effective use of progressive parallel coordinates (PPCs), utilized routinely for high-dimensional data visualization. It discusses how the power of the typical stages of progressive data visualization can also be utilized fully for PPCs. Further, different implementations of the underlying methods and potential application domains are described. The paper also presents empirical results concerning the benefits of PPC with regard to efficient data management and improved presentation, indicating that the proposed approach is able to close the gap between data handling and visualization.

关键词： Lead visualization Logic gates

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