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IntenSelect: Using dynamic object rating for assisting 3D object selection

IntenSelect: Using dynamic object rating for assisting 3D ob...

Joint 9th International Workshop on Immersive Projection Technology and the 11th Eurographics Symposium on Virtual Environments, IPT/EGVE 2005

作者： De Haan, Gerwin Koutek, Michal Post, Frits H. Data Visualization Group Faculty of Electrical Engineering Mathematics and Computer Science Delft University of Technology Netherlands

ISBN: (纸本)3905673215

We present IntenSelect, a novel selection technique that dynamically assists the user in the selection of 3D objects in Virtual Environments. Ray-casting selection is commonly used, although it has limited accuracy and can be problematic in more difficult situations where the intended selection object is occluded or moving. Selection-by-volume techniques, which extend normal ray-casting, provide error tolerance to cope with the limited accuracy. However, these extensions generally are not usable in the more complex selection situations. We have devised a new selection-by-volume technique to create a more flexible selection technique which can be used in these situations. To achieve this, we use a new scoring function to calculate the score of objects, which fall within a user controlled, conic selection volume. By accumulating these scores for the objects, we obtain a dynamic, time-dependent, object ranking. The highest ranking object, or active object, is indicated by bending the otherwise straight selection ray towards it. As the selection ray is effectively snapped to the object, the user can now select the object more easily. Our user tests indicate that IntenSelect can improve the selection performance over ray-casting, especially in the more difficult cases of small objects. Furthermore, the introduced time-dependent object ranking proves especially useful when objects are moving, occluded and/or cluttered. Our simple scoring scheme can be easily extended for special purpose interaction such as widget or application specific interaction functionality, which creates new possibilities for complex interaction behavior. © The Eurographics Association 2005.

关键词： Virtual reality

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Feature tracking in VR for cumulus cloud life-cycle studies

Feature tracking in VR for cumulus cloud life-cycle studies

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Joint 9th International Workshop on Immersive Projection Technology and the 11th Eurographics Symposium on Virtual Environments, IPT/EGVE 2005

作者： Griffith, E.J. Post, F.H. Koutek, M. Heus, T. Jonker, H.J.J. Data Visualization Group Faculty of Electrical Engineering Mathematics and Computer Science Netherlands Department of Multi-Scale Physics Faculty of Applied Sciences Delft University of Technology Netherlands

ISBN: (纸本)3905673215

Feature tracking in large data sets is traditionally an off-line, batch processing operation while virtual reality typically focuses on highly interactive tasks and applications. This paper presents an approach that uses a combination of off-line preprocessing and interactive visualization in VR to simplify and speed up the identification of interesting features for further study. We couch the discussion in terms of our collaborative research on using virtual reality for cumulus cloud life-cycle studies, where selecting suitable clouds for study is simple for the skilled observer but difficult to formalize. The preprocessing involves identifying individual clouds within the data set through a 4D connected components algorithm, and then saving isosurface, bounding box, and volume information. This information is then interactively visualized in our VR Cloud Explorer with various tools and information displays to identify the most interesting clouds. In a small pilot study, reasonable performance, both in the preprocessing phase and the visualization phase, has been measured. © The Eurographics Association 2005.

关键词： Virtual reality

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Robust bayes forecasting for grouped binary data with known distortion interval

Robust bayes forecasting for grouped binary data with known ...

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MS'2004 - International Conference on Modelling and Simulation

作者： Pashkevich, Maxim Department of Mathematical Modelling and Data Analysis Faculty of Applied Mathematics and Computer Science Belarusian State University 4 F. Skaryny Ave. Minsk Belarus

ISBN: (纸本)9856107334

The paper is devoted the problem of robust forecasting for the beta-mixed hierarchical models of grouped binary data in the case of stochastic additive distortions of binary observations. In the case of known lower and upper bounds of the distortion intervals, a new robust minimax Bayes predictor is developed. The performance of the proposed forecasting technique is validated by computer simulation.

关键词： Random processes

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Enhanced stereoscopic imaging

Enhanced stereoscopic imaging

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Proceedings of the Fourth IASTED International Conference on Visualization, Imaging, and Image Processing

作者： Le, Nhu Pochec, P.R. Ware, C. Communications Research Centre 3701 Carling Ave. Ottawa Canada Faculty of Computer Science University of New Brunswick Fredericton Canada Data Visualization Research Lab. University of New Hampshire Durham NH United States

ISBN: (纸本)0889864152

In this paper we introduce a new technique designed to optimize stereoscopic depth perception of small targets embedded in 3D scenes. Central to the technique is a modified version of an image processing algorithm originally designed for gray scale image enhancement. This has been adapted and modified to adjust the stereoscopic depth in a 3D scene while mostly preserving other depth cues such as perspective, texture gradients, size gradients and occlusion. An experimental study to evaluate the algorithm showed that enhanced stereoscopic depth can enable the detection of targets that would otherwise be missed.

关键词： Imaging techniques

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Raman scattering investigation of a Ge/SiO2/Si nanocrystal system under hydrostatic pressure

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Physical Review B 2004年第12期69卷 125333-125333页

作者： Lei Liu K. L. Teo Z. X. Shen J. S. Sun E. H. Ong A. V. Kolobov Y. Maeda Physics Department Blk. S12 Faculty of Science National University of Singapore 2 Science Drive 3 117542 Singapore Department of Electrical and Computer Engineering National University of Singapore 4 Engineering Drive 3 117576 Singapore Mechatronics & Micro System Group Data Storage Institute 117608 Singapore Center for Applied Near-Field Optics Research (CANFOR) National Institute of Advanced Industrial Science and Technology Tsukuba Central 4 1-1-1 Higashi Tsukuba Ibaraki 305-8562 Japan Department of Energy Science and Technology Kyoto University Sakyo-ku Kyoto 606-8501 Japan

We have studied the hydrostatic pressure dependence of Ge nanocrystals embedded in a SiO2 matrix on a Si substrate by Raman scattering at room temperature. During the first cycle of increasing pressure, we observed a step change in the Ge Raman mode from 310.4 to 313.8cm−1 at ∼23kbar. The linear pressure coefficients α obtained before and after the step change at ∼23kbar are 0.42 and 0.64cm−1kbar−1, respectively. Upon decreasing pressure, the Ge mode follows a single slope of pressure coefficient α=0.64cm−1kbar−1. A finite-element analysis was carried out to investigate the elastic-field distribution in the Ge/SiO2/Si nanocrystal system, where the discontinuity of the specific geometric configuration with different elastic constants causes local areas of stress concentration around the interface. The step change of the Raman shifts with pressure at ∼23kbar was attributed to complete delamination between the SiO2 film and the Si substrate.

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Modeling Demand for Inventory Management of Slow-Moving Items in Case of Reporting Errors

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IFAC Proceedings Volumes 2004年第4期37卷 27-32页

作者： Alexandre Dolgui Anatoly Pashkevich Maxim Pashkevich Scientific Methods for Industrial Management Dept. (MSGI) Industrial Engineering and Computer Sciences Center (G2I) Ecole de Mines de Saint Etienne 158 Cours Fauriel 42023 Saint Etienne France Robotic Laboratory Department of Automatic Control Belarusian State University of Informatics and Radioelectronics 6 P.Brovka St. Minsk 220027 Belarus Department of Mathematical Modeling and Data Analysis Faculty of Applied Mathematics and Computer Science Belarusian State University Skarina Av. 4 Minsk 220050 Belarus

The paper is devoted to the problem of modeling demand for inventory management of slow-moving items in the case of reporting errors. It is proposed a generalization of the beta-binomial demand model that takes into account possible reporting errors in the learning sample. For the new model, there are developed identification and forecasting algorithms that provide consistent estimators of the model parameters and mean square optimal forecasts. The efficiency of the proposed approach is illustrated by an application example for slow-moving car parts.

关键词： inventory control error correction statistical inference parameter estimation prediction methods

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Asynchronous Service Discovery in Mobile Ad-hoc Networks

Asynchronous Service Discovery in Mobile Ad-hoc Networks

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Persistence, Scalability, Transactions - database Mechanisms for Mobile Applications 2003

作者： Nagi, Khaled König-Ries, Birgitta Computer Science Department Faculty of Engineering Alexandria University El-Shatby Alexandria Egypt Institute for Program Structures Data Organization Universität Karlsruhe KarlsruheD-76128 Germany

ISBN: (纸本)3885793725

The wide availability of mobile devices equipped with wireless communication devices paves the way for building highly dynamic communities of ad-hoc networks. For an asynchronous service discovery in this environment, we suggest the use of mobile agents. Here, we concentrate on file sharing and exchanging services. We adopt a new asynchronous approach for discovering and locating these files, since the availability of files in this particular domain will change significantly over time when nodes constantly join and leave the network. In this paper, we present a typical application scenario, highlight the main components of the system architecture and discuss the technical challenges facing us while trying to port main infrastructural features of traditional database management systems to our mobile light-weight software agents. © 2003 Gesellschaft fur Informatik (GI). All rights reserved.

关键词： Mobile agents

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Diagrams Based on Structural Object Perception 00

Diagrams Based on Structural Object Perception

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Proceedings of the Working Conference on Advanced Visual Interfaces

作者： Pourang Irani Colin Ware Faculty of Computer Science University of New Brunswick Box 4400 Fredericton NB Canada E3B 2A3 Data Visualization Research Lab Center for Coastal and Ocean Mapping University of New Hampshire Durham NH

ISBN: (纸本)9781581132526

Most diagrams, particularly those used in software engineering, are line drawings consisting of nodes drawn as rectangles or circles, and edges drawn as lines linking them. In the present paper we review some of the literature on human perception to develop guidelines for effective diagram drawing. Particular attention is paid to structural object recognition theory. According to this theory as objects are perceived they are decomposed into 3D set of primitives called geons, together with the skeleton structure connecting them. We present a set of guidelines for drawing variations on node-link diagrams using geon-like primitives, and provide some examples. Results from three experiments are reported that evaluate 3D geon diagrams in comparison with 2D UML (Unified Modeling Language) diagrams. The first experiment measures the time and accuracy for a subject to recognize a sub-structure of a diagram represented either using geon primitives or UML primitives. The second and third experiments compare the accuracy of recalling geon vs. UML diagrams. The results of these experiments show that geon diagrams can be visually analyzed more rapidly, with fewer errors, and can be remembered better in comparison with equivalent UML diagrams.

关键词： perception diagramming geon theory 3D diagrams visual display information visualization

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Development and application of MCAL tools for marine radar instruction

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computer Applications in Engineering Education 1995年第4期3卷 259-259页

作者： Guirguis, S. Korany, E. Abdel-Bary, A. Institute of Graduate Studies and Research Alexandria University Alexandria Egypt Shawkat K. Guirguis:obtained the BSc and M.Sc. degrees in Computer Science and Automatic Control Faculty of Engineering Alexandria University in 1981 and 1984 respectively. In 1988 he obtained a PhD degree in Electronics and Communications Faculty of Engineering Cairo University co-supervised by the Imperial College of Science and Technology University of London where he spent two years as an academic visitor. His current research interests include software quality management multimedia automatic programming and decision support systems. He is currently a lecturer of Computer Science at the Institute of Graduate Studies & Research Alexandria University. Ezzat A. Korany:received the BS degree in Electrical Engineering (Electronics Section) from the University of Alexandria Egypt in 1971 the MS degree in Electrical Engineering (Computer Section) from Ain Shams University Cairo Egypt in 1977 and the PhD degree in Electrical Engineering (Digital Systems) from Florida Institute of Technology U.S.A. in 1982. He is currently an associate professor of Computer Science at the Institute of Graduate Studies & Research University of Alexandria. His research interests are in data communications and multimedia applications computer networks image processing and pattern recognition. Abdel-Latif A. Abdel-Bary:obtained the BEng degree in Electronics Technology from Arab Maritime Transport Academy in 1986. In 1995 he obtained the MSc degree in Information Technology from the Institute of Graduate Studies & Research Alexandria University. His current research interests include ICAL hypermedia and automatic programming.

In this article a multimedia computer-assisted learning (MCAL) system is presented. The major objective of this work was to investigate the potential of using such systems as tools for transferring instructional course information through various types of computer media as opposed to the classic CAL systems. The philosophy and techniques employed to design the system are investigated. Usage of the implemented system and its merits have been illustrated through its application to teach engineering students and technicians the theory and concepts of marine radar. System design, implementation, test, and revision phases are presented and discussed.

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Applying multimedia technology to undergraduate engineering laboratories

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computer Applications in Engineering Education 1995年第3期3卷 157-157页

作者： Elsherbeni, A. Tew, M. Mokaddem, A. Electrical Engineering Department University of Mississippi University Mississippi 38677 Atef Z. Elsherbeni:received an honorary BS degree in Electronics and Communications an honorary BS degree in Applied Physics and a Meng degree in Electrical Engineering all from Cairo University Egypt in 1976 1979 and 1982 respectively and a PhD degree in Electrical Engineering from Manitoba University Canada in 1987. From January to August 1987 he was a postdoctoral fellow at the Electrical Engineering Department University of Manitoba. He joined the faculty at the University of Mississippi in 1987 as an assistant professor and advanced to the rank of associate professor in 1991. His professional interests include microstrip transmission lines and antennas scattering and diffraction numerical techniques and computer applications for electromagnetic education. Dr. Elsherbeni is a senior member of IEEE and a member of Commission B of the International Union of Radio Science (URSI). His honorary memberships include the Electromagnetics Academy and the Scientific Sigma Xi Society. Mark D. Tew:obtained his BS in Electrical Engineering with highest honors in 1971 and an MS in Electrical Engineering in 1973 from the University of Mississippi. He attended the University of Illinois at Urbana-Champaign as a TRW Doctoral Fellow and received the PhD in 1979. He joined the University of Mississippi in 1979 and was appointed associate professor in 1986. His interests lie in improving undergraduate laboratories through the incorporation of computer-aided data acquisition and introduction of multimedia. He is a senior member of IEEE and member of several honorary societies.

This article presents efforts to improve the presentation of material in high frequency, microwave, and electronics laboratories using multimedia technology. A crowded undergraduate curriculum leaves little time to dwell on difficult concepts in these areas of study, yet the laboratory experience is enhanced by greater understanding. A moderate or small-sized electrical engineering department is well suited for a one-on-one approach to teaching where close faculty—student interaction serves to fill many student needs. Even in this environment, better visualization tools may increase learning by reinforcing material introduced in the classroom. This project uses multimedia to enhance instruction and presentation in the high frequency, microwave, and electronics laboratories.

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