检索结果-内蒙古大学图书馆

Proceedings of the workshop on Virtual environments 2003

作者： Joseph J. LaViola Brown University Technology Center for Advanced Scientific Computing and Visualization Providence RI

ISBN: (纸本)9781581136869

We present novel algorithms for predictive tracking of user position and orientation based on double exponential smoothing. These algorithms, when compared against Kalman and extended Kalman filter-based predictors with derivative free measurement models, run approximately 135 times faster with equivalent prediction performance and simpler implementations. This paper describes these algorithms in detail along with the Kalman and extended Kalman Filter predictors tested against. In addition, we describe the details of a predictor experiment and present empirical results supporting the validity of our claims that these predictors are faster, easier to implement, and perform equivalently to the Kalman and extended Kalman filtering predictors.

关键词：

来源：评论

学校读者我要写书评

暂无评论

An experiment comparing double exponential smoothing and Kalman filter-based predictive tracking algorithms

An experiment comparing double exponential smoothing and Kal...

引用

IEEE Annual International Symposium Virtual Reality

作者： J.J. LaViola Advanced Scientific Computing and Visualization Brown University Technology Center Providence RI USA

We present an experiment comparing double exponential smoothing and Kalman filter-based predictive tracking algorithms with derivative free measurement models. Our results show that the double exponential smoothers run approximately 135 times faster with equivalent prediction performance. The paper briefly describes the algorithms used in the experiment and discusses the results.

关键词： Smoothing methods Kalman filters Prediction algorithms Equations Vectors Predictive models Quaternions Interpolation Scientific computing visualization

来源：评论

学校读者我要写书评

暂无评论

A comparison of unscented and extended Kalman filtering for estimating quaternion motion

A comparison of unscented and extended Kalman filtering for ...

引用

American Control Conference (ACC)

作者： J.J. LaViola For Advanced Scientific Computing and Visualization Brown University Technology Center Providence RI USA

The unscented Kalman filter is a superior alternative to the extended Kalman filter for a variety of estimation and control problems. However, its effectiveness for improving human motion tracking for virtual reality applications in the presence of noisy data has been unexplored. In this paper, we present an empirical study comparing the performance of unscented and extended Kalman filtering for improving human head and hand tracking. Specifically, we examine human head and hand orientation motion signals, represented with quaternions, which are critical for correct viewing perspectives in virtual reality. Our experimental results and analysis indicate that unscented Kalman filtering performs equivalently with extended Kalman filtering. However, the additional computational overhead of the unscented Kalman filter and quasi-linear nature of the quaternion dynamics lead to the conclusion that the extended Kalman filter is a better choice for estimating quaternion motion in virtual reality applications.

关键词： Kalman filters Filtering Motion estimation Quaternions Virtual reality Humans Tracking Head Application software Jacobian matrices

来源：评论

学校读者我要写书评

暂无评论

Parallel cell projection rendering of adaptive mesh refinement data

Parallel cell projection rendering of adaptive mesh refineme...

引用

IEEE Symposium on Parallel and Large-Data visualization and Graphics (PVG)

作者： G.H. Weber M. Ohler O. Kreylos J.M. Shalf E.W. Bethel B. Hamann G. Scheuermann Visualization Group National Energy Research Scientific Computing Center (NERSC) Lawrence Berkeley National Laboratory Berkeley CA USA AG Graphische Datenverabeitung und Computergeometrie FB Informatik University of Kaiserslautern Kaiserslautern Germany Center for Image Processing and Integrated Computing Center for Image Processing and Integrated Computing (CIPIC) Department of Computer Science University of California Davis CA USA Center for Image Processing and Integrated Computing Department of Computer Science University of California Davis CA USA

Adaptive mesh refinement (AMR) is a technique used in numerical simulations to automatically refine (or de-refine) certain regions of the physical domain in a finite difference calculation. AMR data consists of nested hierarchies of data grids. As AMR visualization is still a relatively unexplored topic, our work is motivated by the need to perform efficient visualization of large AMR data sets. We present a software algorithm for parallel direct volume rendering of AMR data using a cell-projection technique on several different parallel platforms. Our algorithm can use one of several different distribution methods, and we present performance results for each of these alternative approaches. By partitioning an AMR data set into blocks of constant resolution and estimating rendering costs of individual blocks using an application specific benchmark, it is possible to achieve even load balancing.

关键词： Adaptive mesh refinement Data visualization Rendering (computer graphics) Spatial resolution Partitioning algorithms Load management Parallel programming Graphics Physics computing Computational efficiency

来源：评论

学校读者我要写书评

暂无评论

Scalability of a low-cost multi-Teraflop Linux cluster for high-end classical atomistic and quantum mechanical simulations

Scalability of a low-cost multi-Teraflop Linux cluster for h...

引用

International Parallel and Distributed Processing Symposium, IPDPS 2003

作者： Kikuchi, Hideaki Kalia, Rajiv K. Nakano, Aiichiro Vashishta, Priya Shimojo, Fuyuki Saini, Subhash Collaboratory for Multiscale Simulations Department of Computer Science Department of Physics and Astronomy Department of Materials Science Department of Biomedical Engineering University of Southern California Los AngelesCA90089 United States Concurrent Computing Laboratory for Materials Simulations Biological Computation and Visualization Center Department of Computer Science Department of Physics and Astronomy Louisiana State University Baton RougeLA70803 United States Faculty of Integrated Arts and Sciences Hiroshima University Higashi-Hiroshima739-8521 Japan IT Modeling and Simulation NASA Ames Research Center Moffett FieldCA94035 United States

ISBN: (纸本)0769519261

Scalability of a low-cost, Intel Xeon-based, multi-Teraflop Linux cluster is tested for two high-end scientific applications: Classical atomistic simulation based on the molecular dynamics method and quantum mechanical calculation based on the density functional theory. These scalable parallel applications use spacetime multiresolution algorithms and feature computational-space decomposition, wavelet-based adaptive load balancing, and spacefilling-curve-based data compression for scalable I/O. Comparative performance tests are performed on a 1024-processor Linux cluster and a conventional higher-end parallel supercomputer, 1184-processor IBM SP4. The results show that the performance of the Linux cluster is comparable to that of the SP4. We also study various effects, such as the sharing of memory and L2 cache among processors, on the performance. © 2003 IEEE.

关键词： Scalability

来源：评论

学校读者我要写书评

暂无评论

Which comes first, usability or utility?

Which comes first, usability or utility?

引用

IEEE Conference on visualization

作者： G. Grinstein A. Kobsa C. Plaisant J.T. Stasko Institute for Visualization and Perception Research University of Massachusetts Lowell Lowell MA University of California School of Information and Computer Science Irvine CA Human Computer Interaction Laboratory University of Maryland College Park MD Georgia Institute of Technology College of Computing/GVU Center Atlanta GA

来源：评论

学校读者我要写书评

暂无评论

Scalability of a low-cost multi-Teraflop Linux cluster for high-end classical atomistic and quantum mechanical simulations

Scalability of a low-cost multi-Teraflop Linux cluster for h...

引用

International Symposium on Parallel and Distributed Processing (IPDPS)

作者： H. Kikuchi R.K. Kalia A. Nakano P. Vashishta F. Shimojo S. Saini Concurrent Computing Laboratory for Materials Simulations Biological Computation and Visualization Center Department of Computer Science Department of Physics & Astronomy Louisiana State University Baton Rouge LA USA Collaboratory for Multiscale Simulations Department of Computer Science Department of Physics & Astronomy Department of Materials Science Department of Biomedical Engineering University of Southern California Los Angeles CA USA Faculty of Integrated Arts and Sciences Hiroshima University Higashi Hiroshima Japan IT Modeling and Simulation NASA Ames Research Center Moffett Field CA USA

关键词： Scalability Linux Quantum mechanics Computational modeling Testing Density functional theory Clustering algorithms Concurrent computing High performance computing Load management

来源：评论

学校读者我要写书评

暂无评论

Pop through button devices for VE navigation and interaction

Pop through button devices for VE navigation and interaction

引用

IEEE Annual International Symposium Virtual Reality

作者： R.C. Zeleznik J.J. LaViola D. Acevedo Feliz D.F. Keefe Advanced Scientific Computing and Visualization Brown University Technology Center Providence RI USA

ISBN: (纸本)0769514928

Presents a novel class of virtual reality input devices that combine pop-through buttons with 6-DOF trackers. Compared to similar devices that use conventional buttons, pop-through devices double the number of potential discrete interaction modes, since each button has two activation states corresponding to light and firm pressure. This additional state per button provides a foundation to address a range of shortcomings with conventional virtual environment (VE) input devices that includes reducing the physical dexterity required to perform interactions, reducing the cognitive complexity of some compound tasks and enabling the design of less obtrusive devices without sacrificing expressive power. Specifically, we present two novel input devices: the FingerSleeve was designed to be minimally obtrusive physically, whereas the TriggerGun was designed to be physically similar to, yet more functional than a conventional hand-held trigger device. Further, we present a set of novel navigation and interaction techniques that leverage the capabilities of our pop-through button devices to improve interaction quality and provide insight into harnessing the potential of pop-through buttons for other tasks. Finally, we discuss how we incorporated one of our devices into a real application.

关键词： Navigation Fingers Electronic switching systems Scientific computing visualization Virtual environment Virtual reality

来源：评论

学校读者我要写书评

暂无评论

On endmember detection in hyperspectral images with morphological associative memories

On endmember detection in hyperspectral images with morpholo...

引用

作者： Graña, Manuel Raducanu, Bogdan Sussner, Peter Ritter, Gerhard Dept. CCIA Universidad Pais Vasco Spain Institute of Mathematics Statistics and Scientific Computing State University of Campinas Brazil Center for Computer Vision and Visualization University of Florida United States

ISBN: (纸本)354000131X

Morphological Associative Memories (MAM) are a construct similar to Hopfield Associative Memories defined on the (R,+, ∨, ∧) algebraic system. The MAM posses excellent recall properties for undistorted patterns. However they suffer from the sensitivity to specific noise models, that can be characterized as erosive and dilative noise. We find that this sensitivity may be made of use in the task of Endmember determination for the Spectral Unmixingof Hyperspectral Images. © Springer-Verlag 2002.

关键词： Associative processing

来源：评论

学校读者我要写书评

暂无评论

Novel uses of Pinch Gloves™ for virtual environment interaction techniques

引用

Virtual Reality 2002年第3期6卷 122-129页

作者： Bowman, D.A. Wingrave, C.A. Campbell, J.M. Ly, V.Q. Rhoton, C.J. Department of Computer Science Virginia Tech. Blacksburg VA United States College of Computing Graphics Visualization and Usability Center Georgia Institute of Technology GA United States Department of Computer Science (0106) Virginia Tech. Blacksburg VA 24061 United States

The usability of three-dimensional (3D) interaction techniques depends upon both the interface software and the physical devices used. However, little research has addressed the issue of mapping 3D input devices to interaction techniques and applications. This is especially crucial in the field of Virtual Environments (VEs), where there exists a wide range of potential 3D input devices. In this paper, we discuss the use of Pinch Gloves™ - gloves that report contact between two or more fingers - as input devices for VE systems. We begin with an analysis of the advantages and disadvantages of the gloves as a 3D input device. Next, we present a broad overview of three novel interaction techniques we have developed using the gloves, including a menu system, a text input technique, and a two-handed navigation technique. All three of these techniques have been evaluated for both usability and task performance. Finally, we speculate on further uses for the gloves. © Springer-Verlag London Ltd.

关键词： 3D Input Devices Interaction Techniques Pinch Gloves Usability Evaluation Virtual Environments

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：