检索结果-内蒙古大学图书馆

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

来源：评论

学校读者我要写书评

暂无评论

Liquidlike correlations in single-crystalline Y2Mo2O7: An unconventional spin glass

引用

Physical Review B 2014年第5期89卷 054433-054433页

作者： H. J. Silverstein K. Fritsch F. Flicker A. M. Hallas J. S. Gardner Y. Qiu G. Ehlers A. T. Savici Z. Yamani K. A. Ross B. D. Gaulin M. J. P. Gingras J. A. M. Paddison K. Foyevtsova R. Valenti F. Hawthorne C. R. Wiebe H. D. Zhou Department of Chemistry University of Manitoba Winnipeg Manitoba R3T 2N2 Canada Department of Physics and Astronomy McMaster University Hamilton Ontario L8S 4M1 Canada Department of Physics and Astronomy University of Waterloo Waterloo Ontario N2L 3G1 Canada Perimeter Institute for Theoretical Physics 31 Caroline Street North Waterloo Ontario N2L 2Y5 Canada School of Physics HH Wills Physics Laboratory University of Bristol Bristol BS8 1TL United Kingdom Indiana University 2401 Milo B. Sampson Lane Bloomington Indiana 47408 USA NIST Center for Neutron Research National Institute of Standards and Technology Gaithersburg Maryland 20899-6102 USA Department of Materials Science and Engineering University of Maryland College Park Maryland 20742 USA Quantum Condensed Matter Division Neutron Sciences Directorate Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA Neutron Data Analysis and Visualization Division Neutron Sciences Directorate Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA Canadian Neutron Beam Centre Chalk River Ontario K0J 1P0 Canada Canadian Institute for Advanced Research 180 Dundas St. W. Toronto Ontario M5G 1Z8 Canada Brockhouse Institute for Materials Research McMaster University Hamilton Ontario L8S 4M1 Canada Department of Chemistry University of Oxford Inorganic Chemistry Laboratory South Parks Road Oxford OX1 3QR United Kingdom ISIS Facility Rutherford Appleton Laboratory Chilton Didcot Oxfordshire OX11 0QX United Kingdom Institut für Theoretische Physik Goethe-Universität Frankfurt Frankfurt am Main 60438 Germany Department of Geological Sciences University of Manitoba Winnipeg Manitoba R3T 2N2 Canada Department of Chemistry University of Winnipeg 515 Portage Ave. Winnipeg Manitoba R3B 2E9 Canada Department of Physics and Astronomy University of Tennessee Knoxville Tennessee 37996-1200 USA National High Magnetic Field Laboratory Florida State University Tallahassee Florida 32306-4005 USA

The spin-glass behavior of Y2Mo2O7 has remained a puzzle for nearly three decades. Free of bulk disorder within the resolution of powder diffraction methods, it is thought that this material is a rare realization of a spin glass resulting from weak disorder such as bond disorder or local lattice distortions. Here we report on the single-crystal growth of Y2Mo2O7. Using neutron scattering, we present isotropic magnetic diffuse scattering occurring below the spin-glass transition. Our attempts to model the diffuse scattering using a computationally exhaustive search of a class of simple spin Hamiltonians show no agreement with the experimentally observed energy-integrated (diffuse) neutron scattering. This suggests that spin degrees of freedom are insufficient to describe this system. Indeed, a T2 temperature dependence in the heat capacity and density functional theory calculations hint at the presence of a significant frozen degeneracy in both the spin and orbital degrees of freedom resulting from spin-orbital coupling (Kugel-Khomskii type) and random fluctuations in the Mo environment at the local level.

关键词： SPIN glasses SINGLE crystals X-ray powder diffraction LATTICE theory NEUTRON scattering ISOTROPIC properties HAMILTONIAN systems

来源：评论

学校读者我要写书评

暂无评论

Sketch-based 3D model retrieval using keyshapes for global and local representation

Sketch-based 3D model retrieval using keyshapes for global a...

引用

5th Eurographics Workshop on 3D Object Retrieval, EG 3DOR 2012

作者： Saavedra, J.M. Bustos, B. Schreck, T. Yoon, S. Scherer, M. KDW-PRISMA Research Group Department of Computer Science University of Chile Chile Data Analysis and Visualization Group University of Konstanz Germany Yonsei Institute of Convergence Technology Yonsei University Korea Republic of GRIS TU Darmstadt Germany

ISBN: (纸本)9783905674361

Since 3D models are becoming more popular, the need for effective methods capable of retrieving 3D models is becoming crucial. Current methods require an example 3D model as query. However, in many cases, such a query is not easy to get. An alternative is using a hand-drawn sketch as query. In this work, we present a new keyshape based approach named HKO-KASD for retrieving 3D models using rough sketches as queries. Our approach comprises two general steps. First, a global descriptor is used to determine the appropriate viewpoint for each model. Second, we apply a local matching process to determine the final ranking for an input sketch. To this end, we present a local descriptor capable of working with sketch representations. The global descriptors as well as the local descriptors rely on a set of keyshapes precomputed from 2D representations of 3D models and from the query sketch as well. We evaluate our method using the first-tier precision and compare it with current approaches (HELO, STELA). Our results show a significant increase in precision for many classes of 3D models. © The Eurographics Association 2012.

关键词： Self organizing maps

来源：评论

学校读者我要写书评

暂无评论

Graph-based combinations of fragment descriptors for improved 3D object retrieval 12

Graph-based combinations of fragment descriptors for improve...

引用

3rd ACM Multimedia Systems Conference, MMSys'12

作者： Schreck, Tobias Scherer, Maximilian Walter, Michael Bustos, Benjamin Yoon, Sang Min Kuijper, Arjan Data Analysis and Visualization Group University of Konstanz Germany Interactive Graphics Systems Technische Universität Darmstadt Germany KDW+PRISMA Department of Computer Science University of Chile Chile Yonsei Institute of Convergence Technology Yonsei University Korea Republic of Fraunhofer Institute for Computer Graphics Research Darmstadt Germany

ISBN: (纸本)9781450311311

3D Object Retrieval is an important field of research with many application possibilities. One of the main goals in this research is the development of discriminative methods for similarity search. The descriptor-based approach to date has seen a lot of research attention, with many different extraction algorithms proposed. In previous work, we have introduced a simple but effective scheme for 3D model retrieval based on a spatially fixed combination of 3D object fragment descriptors. In this work, we propose a novel flexible combination scheme based on finding the best matching fragment descriptors to use in the combination. By an exhaustive experimental evaluation on established benchmark data we show the capability of the new combination scheme to provide improved retrieval effectiveness. The method is proposed as a versatile and inexpensive method to enhance the effectiveness of a given global 3D descriptor approach. © 2012 ACM.

关键词： Self organizing maps

来源：评论

学校读者我要写书评

暂无评论

Topology exploration with hierarchical landscapes

Topology exploration with hierarchical landscapes

引用

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

来源：评论

学校读者我要写书评

暂无评论

Structural and magnetic properties in the quantum S=12 dimer system Ba3(Cr1−xVx)2O8 with site disorder

引用

Physical Review B 2013年第14期87卷 144427-144427页

作者： Tao Hong L. Y. Zhu X. Ke V. O. Garlea Y. Qiu Y. Nambu H. Yoshizawa M. Zhu G. E. Granroth A. T. Savici Zheng Gai H. D. Zhou Quantum Condensed Matter Division Oak Ridge National Laboratory Oak Ridge Tennessee 37831-6393 USA Materials Science Division Argonne National Laboratory Argonne Illinois 60439 USA Department of Physics and Astronomy Michigan State University East Lansing Michigan 48824 USA Center for Neutron Research National Institute of Standards and Technology Gaithersburg Maryland 20899 USA Department of Materials and Engineering University of Maryland College Park Maryland 20742 USA Institute of Multidisciplinary Research for Advanced Materials Tohoku University 2-1-1 Katahira Sendai 980-8577 Japan Neutron Science Laboratory Institute for Solid State Physics University of Tokyo 106-1 Shirakata Tokai Ibaraki 319-1106 Japan Neutron Data Analysis and Visualization Division Oak Ridge National Laboratory Oak Ridge Tennessee 37831-6393 USA Center for Nanophase Materials Sciences Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA National High Magnetic Field Laboratory Florida State University Tallahassee Florida 32306-4005 USA Department of Physics and Astronomy University of Tennessee Knoxville Tennessee 37996-1200 USA

We report a comprehensive study of dc susceptibility, specific-heat, neutron-diffraction, and inelastic neutron-scattering measurements on polycrystalline Ba3(Cr1−xVx)2O8 samples, where x=0, 0.06, 0.15, and 0.53. A Jahn-Teller structure transition occurs for x=0, 0.06, and 0.15 samples, and the transition temperature is reduced upon vanadium substitution from 70(2) K at x=0 to 60(2) K at x=0.06 and 0.15. The structure becomes less distorted as x increases, and such transition disappears at x=0.53. The observed magnetic excitation spectrum indicates that the singlet ground state remains unaltered and spin-gap energy Δ=1.3(1) meV is identical within the instrument resolution for all x. In addition, the dispersion bandwidth W decreases with increase of x. At x=0.53, W is reduced to 1.4(1) meV from 2.0(1) meV at x=0.

关键词： QUANTUM dimer models MAGNETIC susceptibility measurement SPECIFIC heat measurement NEUTRON diffraction INELASTIC neutron scattering TRANSITION temperature JAHN-Teller effect POLYCRYSTALS

来源：评论

学校读者我要写书评

暂无评论

Isosurface extraction from hybrid unstructured grids containing pentahedral elements

Isosurface extraction from hybrid unstructured grids contain...

引用

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

来源：评论

学校读者我要写书评

暂无评论

Progressive parallel coordinates

Progressive parallel coordinates

引用

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

来源：评论

学校读者我要写书评

暂无评论

Abstract: Exploring Performance data with Boxfish

Abstract: Exploring Performance Data with Boxfish

引用

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.

关键词：

来源：评论

学校读者我要写书评

暂无评论

VirCA NET: A case study for collaboration in shared virtual space

VirCA NET: A case study for collaboration in shared virtual ...

引用

International Conference on Cognitive Infocommunications (CogInfoCom)

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

To take up the challenge of global distributed companies, Manufacturing Engineering has to be accomplished in a worldwide collaborative way. Design and development of production processes and their execution are nowadays spread all over the world. To ensure quality standards and to create synergies between spatially distributed entities, distance collaboration tools must be provided to allow cooperation even over large distances. The Virtual Reality (VR) is thereby offering beneficial capabilities to exchange current planning stages, identify problems and solve them cooperatively. This paper introduces a new approach for distance collaboration, which enables users to work in a joint virtual space, nearly as if they were working together in the same place. Therefore two full-immersive CAVE-like systems are interconnected using the VirCA (Virtual Collaboration Arena) platform. The paper describes the requirements of Mechanical Engineers towards distance collaboration tools and the technical challenges solved with the enhanced VirCA framework. This working prototype is one premier application in the field of VR-enhanced spatially distributed collaboration. A typical use case scenario is provided to highlight the interaction and cooperation capabilities offered by VirCA NET.

关键词： Collaboration Planning Robots Production facilities Manufacturing Virtual reality Production systems

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：