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Conference on Virtual Reality 2010

作者： Tang, Ziying Rong, Guodong Guo, Xiaohu Prabhakaran, B. Univ Texas Dallas Dept Comp Sci Richardson TX 75083 USA

ISBN: (纸本)9781424462582

Collaborative virtual environment has been limited on static or rigid 3d models, due to the difficulties of real-time streaming of large amounts of data that is required to describe motions of 3d deformable models. Streaming shape deformations of complex 3d models arising from a remote user's manipulations is a challenging task. In this paper, we present a framework based on spectral transformation that encodes surface deformations in a frequency format to successfully meet the challenge, and demonstrate its use in a distributed virtual environment. Our research contributions through this framework include: i) we reduce the data size to be streamed for surface deformations since we stream only the transformed spectral coefficients and not the deformed model;ii) we propose a mapping method to allow models with multi-resolutions to have the same deformations simultaneously;iii) our streaming strategy can tolerate loss without the need for special handling of packet loss. Our system guarantees real-time transmission of shape deformations and ensures the smooth motions of 3d models. Moreover, we achieve very effective performance over real Internet conditions as well as a local LAN. Experimental results show that we get low distortion and small delays even when surface deformations of large and complicated 3d models are streamed over lossy networks.

关键词： Collaborative Interaction distributed Virtual Reality 3d Shape deformation

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A Fast Ultrasound Molecular Imaging Method and its 3d visualization in vivo

A Fast Ultrasound Molecular Imaging Method and its 3D Visual...

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2011 IEEE Ultrasonics symposium (IUS 2011)

作者： Xiaowen Hu Lisa Mahakian Charles Caskey Julie Beegle dustin Kruse Joshua Rychak Patrick Sutcliffe Katherine Ferrara University of California Davis CA Targeson Inc. San Diego CA

ISBN: (纸本)9781457712531

Using targeted microbubbles (MBs), ultrasound molecular imaging can be used to selectively and specifically visualize upregulated vascular receptors. In order to acquire bound MB echoes, a delay of ～7-15 minutes is commonly required for the clearance of freely circulating MBs. Here, we test whether echoes from MBs can be distinguished from the surrounding tissue, based on the transmission of pulses at low (1.5 MHz) and reception at high (5.5 MHz) frequencies (TLRH), without the requirement for destructive pulses. Pulses with a peak negative pressure of 230 kPa were transmitted (10 fps) and a 7th order IIR pulse-to-pulse filter was applied to the TLRH radiofrequency (RF) data to distinguish the signature of bound MBs from that of flowing MBs. 3d images of the accumulation of intravenously-administrated integrin-targeted MBs in a Met-1 mouse tumor model were acquired. An in vitro study demonstrated that the T2R15 contrast imaging technique has a ～2-fold resolution improvement over 2MHz contrast pulse sequencing (CPS) imaging. By applying the 7th order IIR filter to the TLRH RF data acquired at 2 minutes, echoes from flowing MBs in the surrounding tissue region were suppressed by 26±2 dB, while the signal intensity within the tumor was suppressed by 4±1 dB. The targeted images correctly represented the distribution of bound MBs. After the filter, the signal intensity resulting from cyclic RGd bearing MBs was 25±2 dB higher than that after the injection of non-targeted MBs.

关键词： targeted microbubble molecular imaging slow time filter TLRH

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Simple shear simulation of 3d irregularly-shaped particles by image-based dEM

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GRANULAR MATTER 2010年第5期12卷 491-497页

作者： Katagiri, Jun Matsushima, Takashi Yamada, Yasuo Univ Tsukuba Dept Engn Mech & Energy Grad Sch Syst & Informat Engn Tsukuba Ibaraki Japan

This paper describes an image-based dEM taking account of the irregular shape of solid particles in a direct manner. A micro X-Ray CT at SPring-8 (a synchrotron radiation facility in Japan) was employed to obtain high quality CT images for detecting correctly the shape of particles. The digitized 3d shape data of each particle was automatically obtained by an original image-processing technique. The particle shape was modeled by a cluster of several spherical elements using dynamic optimization method. The accuracy of the modeling can be controlled by the number of elements forming each particle. Using such modeled particles a series of simple shear simulations were performed for the specimens with various void ratios. It was found that 10-element model can quantitatively reproduce the shear behavior of relatively-dense specimens. On the other hand, in order to well simulate the packing structure and the shear behavior of loose specimens, 10-element model is found to be insufficient and more accurate model would be necessary. This result implies that the overall grain shape that is relevant to the moment transmission between grains is important in densely-packed granular assembly, while small surface angularity plays considerable role in loosely-packed granular assembly.

关键词： discrete Element Method (dEM) Irregular particle shape Image-based modeling Simple shear

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Research on 3d Symbolic Representation of Geographical Information

Research on 3D Symbolic Representation of Geographical Infor...

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18th international Conference on Geoinformatics

作者： Wei Yongjun Ji Guojie Hou Suyuan Chen Yingdong Xian Inst Surveying & Mapping Xian Peoples R China Inst Geograph Sci & Nat Resource Res Beijing Peoples R China

ISBN: (纸本)9781424473021

the symbolic database system is the basic tool of geospatial data representation in map. In the past, many researchers didn't focus on 3d map symbols but mostly on 2d map symbols. In 3d GIS, all geographic phenomena and spatial entities need to be represented by the corresponding 3d symbol models. So establishing a complete set of 3d map symbolic database with expression becomes critical in technology development of 3d map visualization. Based on the theory of map information transmission, the categorical rule and drafting law are researched and a principle of establishing a 3d symbol is presented in this paper, which contains two aspects The one is that all kinds of spatial feature information which are suitable for description by 3d symbol models have been identified, the other is that it should be implemented at the viewpoint of computer graphics and visualization. And the basic concept of 3d map symbol model and the relation between traditional 2d symbol and 3d map symbol are stated, which include (1) 3d symbol is not to deny or abort using 2d symbols, but to complement and enhance 2d symbols;(2) 3d symbol enriches and augments the way of map representation, promotes the study on the latest 3d area of cartography, and acts as critical role on research and development of new map visual products. Meanwhile, a principle of generating a 3d symbol is also proposed, which are (1) description in abstraction and visualization;(2) logicality;(3) conciseness;(4) feasibility. The research in this paper lays theory fundament for establishment and applications of 3d symbol database. In addition, the approach and basic procedure of 3d symbol modeling is given in detail which consists of 3d entities modeling, symbol render and assignment processing, scenery conflating of 2d symbol and dEM, symbol algorithm design, etc. The technology of texture gradational blending is adopted to deal with the crack of rendering line symbols and area symbols caused by boundary transition, which

关键词： geographic information 3d modeling 3d symbolic model symbolization

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Using ISO 10303-224 for 3d visualization of Manufacturing Features

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8th international Heinz Nixdorf symposium on Advanced Manufacturing and Sustainable Logistics

作者： Teich, Tobias Militzer, Joerg Jahn, Franziska Kretz, daniel Neumann, Tim Univ Appl Sci D-08012 Zwickau Germany

ISBN: (纸本)9783642124617

Globalization leads to increasing competition for companies. Next to this, customer seek for individual products, leading to a boost in costs for product development. We try to tackle both aspects in our current research. We are trying to develop a solution for the automatic extraction of routings from a three-dimensional product description. This leads to two advantages. First, costs for product development are decreasing because labour intensive planning will be eliminated. Second, the time between customer inquiry and offer can be reduced, which is an additional advantage to get ahead of competition. To develop such a solution, different aspects have to be considered. This paper deals with the product representation, which should allow us to automatically assign process steps to design-elements. Feature-based design is a very promising concept for optimizing the entire product development by enhancing the product model with significant information. An approach for its implementation is the ISO-standard 10303 "Standard for the Exchange of Product model data". ISO-10303 provides a formal reference model for a consistent, standardized and complete product description which is fundamentally required for automated process planning. This paper summarizes the reasons for choosing the formally specified feature objects of the ISO-10303 application protocol 224 for 3d-visualization and how we implemented the concept "geometry from feature". Therefore we have developed a modular "viewer-concept" for connecting suitable geometric modeling cores like ACTS with our AP 224 feature library which will be presented in the paper. Additionally, a short overview of automated process planning will be given.

关键词： Feature-based design 3d visualization ISO 10303 Product model data exchange STEP

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Proceedings - Web3d 2010: 15th international Conference on Web 3d Technology

Proceedings - Web3D 2010: 15th International Conference on W...

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15th international Conference on Web 3d Technology, Web3d 2010

ISBN: (纸本)9781450302098

The proceedings contain 21 papers. The topics discussed include: a modern declarative surface shader for X3d;shadow maps and projective texturing in X3d;a flexible framework to personalize 3d web users experience;dWeb3d: a toolkit for developing X3d applications in a simplified environment;service-oriented scene graph manipulation;FO3d - formatting objects for PdF3d;storyboarding and pre-visualization with X3d;integrating a Web3d Interface into an E-learning Platform;cognitive scaffolding in Web3d learning systems: a case study for form and structure;collaborative steering and post-processing of simulations on HPC resources: everyone, anytime, anywhere;remote scientific visualization of progressive 3d meshes with X3d;visualization methods for molecular studies on the web platform;ChartFlight - from spreadsheets to computer-animated data flights;and extending the Web3d: design of conventional GUI libraries in X3d.

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Hyperspectral image compression with modified 3d SPECK

Hyperspectral image compression with modified 3D SPECK

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2010 7th international symposium on Communication Systems, Networks and digital Signal processing, CSNdSP 2010

作者： Ngadiran, Ruzelita Boussakta, Said Bouridane, Ahmed Syarif, Bayan School of Electrical Electronic and Computer Engineering University of Newcastle upon Tyne Newcastle upon Tyne United Kingdom School of Computing Engineering and Information Sciences Northumbria University Newcastle upon Tyne United Kingdom

ISBN: (纸本)9781861353696

Hyperspectral image consist of a set of contiguous images bands collected by a hyperspectral sensor. The large amount of data of hyperspectral images emphasizes the importance of efficient compression for storage and transmission. This paper proposes the simplified version of the three dimensional Set Partitioning Embedded bloCK (3d SPECK) algorithm for lossy compression of hyperspectral image. A three dimensional discrete wavelet transform (3d dWT) can fully exploit the interband correlation in a volumetric block. This provides the obvious way to process data such as with hyperspectral images. The 3d structure of the SPECK algorithm will suitably extend the exploitation of interband dependence and correlation. The proposed algorithm maintains the 3d SPECK algorithm with modification of the implementation without using any list to store the significant information. This would reduce the memory requirement of the embedded coding algorithm and improve the coding time to compress the images. © 2010 IEEE.

关键词： discrete wavelet transforms

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GPU volume rendering in 3d echocardiography: Real-time pre-processing and ray-casting

GPU volume rendering in 3D echocardiography: Real-time pre-p...

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2010 IEEE international Ultrasonics symposium, IUS 2010

作者： Kiss, Gabriel Steen, Erik Åsen, Jon Petter Torp, Hans G. Norwegian University of Science and Technology Medical Imaging Laboratory MILAB Trondheim Norway GE Vingmed Ultrasound Horten Norway University of Oslo Department of Informatics Oslo Norway Norwegian University of Science and Technology Department of Circulation and Medical Imaging Trondheim Norway

ISBN: (纸本)9781457703829

Since real-time acquisition of 3d echocardiographic data is achievable in practice, many volume rendering algorithms have been proposed for visualization purposes. However, due to the large amounts of data and computations involved a tradeoff between image quality and computational efficiency has to be made. The main goal of our study was to generate high quality volume renderings in real-time, by implementing preprocessing and ray-casting algorithms directly on the GPU. Furthermore the advantage of combining a-priori anatomic and functional information with the volume rendered image was also investigated. The proposed algorithms were implemented both in CUdA and OpenCL and validated on patient datasets acquired using a GE Vivid7 dimensions system. Assuming a 512512 pixels output resolution, average running times of 4.2 ms/frame are achievable on high-end graphics systems. Furthermore a good correspondence between wall thickening and segmental longitudinal strain values was visually observed. By implementing ray-casting on the GPU, the overall processing time is significantly reduced, thus making real-time interactive 3d volume rendering feasible. Combining anatomical and functional information allows for a quick visual assessment of a given case. © 2010 IEEE.

关键词： Volume rendering

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3d visualization OF CONCENTRATIONS FROM STOCHASTIC AGENT-BASEd SIGNAL TRANSdUCTION SIMULATIONS

3D VISUALIZATION OF CONCENTRATIONS FROM STOCHASTIC AGENT-BAS...

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7th IEEE international symposium on Biomedical Imaging: From Nano to Macro

作者： Falk, Martin Klann, Michael Reuss, Matthias Ertl, Thomas Univ Stuttgart VISUS Visualizat Res Ctr Stuttgart Germany Univ Stuttgart Inst Biochem Engn & Ctr Syst Biol Stuttgart Germany

ISBN: (纸本)9781424441266

Cellular signal transduction involves a transport step from the plasma membrane towards the nucleus, during which the signaling molecules are partly deactivated in control loops. This leads to a gradient in the concentration of active signaling molecules. The low number of molecules introduces spatio-temporal fluctuations and the asymmetric cellular architecture further increases the complexity. We propose a technique to represent this pattern in a continuous three-dimensional concentration map. The local concentration is computed and visualized with volume rendering techniques at interactive frame rates and is therefore well-suited for time-dependent data. Our approach allows the transition from the nano-scale of single and discrete signaling proteins to a continuous signal on the cell level. In the application context of this paper, we employ an agent-based Monte Carlo simulation to calculate the actual particle positions depending on reaction and transport parameters in the cell. The applicability of the proposed technique is demonstrated by an investigation of the effects of different transport parameters in Mitogen-activated protein kinase (MAPK) signaling.

关键词： Cellular signal transduction agent-based simulation protein concentration visualization direct volume rendering

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Using Web Services as Functional-Level Plug Ins for Interactive 3d Medical Visualisation

Using Web Services as Functional-Level Plug Ins for Interact...

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14th international Conference on Information Visualisation (IV)

作者： Wang, Tao Zhao, Youbing Liu, Enjie Clapworthy, Gordon J. Zhao, Xia Wei, Hui dong, Feng Univ Bedfordshire Dept Comp Sci & Technol Luton Beds England

ISBN: (纸本)9780769541655

Web services provide remote access to distributed resources and processes through uniform interfaces. However, the latency associated with data transmission has meant that they are generally applied to non-interactive data processing. Interactive applications, in which many more user interactions and data transmissions are involved, are difficult to adapt to web service based frameworks, particularly if the interactive investigation involves large datasets. In medical imaging and visualisation, user interactions are generally a prerequisite for the detailed study and manipulation of data. As a result of major scientific initiatives, such as the Virtual Physiological Human, in which large data repositories are being set up at a variety of sites, it is becoming increasingly common for the data being investigated to be stored on a remote server. Consequently, it is now highly desirable to develop a means by which web service based interactive visualisation can be applied to distributed medical data access and clinical collaboration. This paper presents a functional-level plug-in based architecture for interactive data visualisation via web services which is being implemented within the EC-funded ContraCancrum project.

关键词： web service interactive visualisation functional-level plug in data-preview service mesh simplification Virtual Physiological Human

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