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Visualising pipeline sensor datasets with modified incremental orthogonal centroid algorithm

International Journal of computer science Issues 2011年第5 5-1期8卷 268-278页

作者： Folorunso, Olufemi Ayinde Mohd, Shahrizal Sunar UTMViCubeLab Department of Computer Graphics and Multimedia Faculty of Computer Science and Information Systems Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia

Each year, millions of people suffer from after-effects of pipeline leakages, spills, and eruptions. Leakages Detection Systems (LDS) are often used to understand and analyse these phenomena but unfortunately could not offer complete solution to reducing the scale of the problem. One recent approach was to collect datasets from these pipeline sensors and analyse offline, the approach yielded questionable results due to vast nature of the datasets. These datasets together with the necessity for powerful exploration tools made most pipelines operating companies " data rich but information poor". Researchers have therefore identified problem of dimensional reduction for pipeline sensor datasets as a major research issue. Hence, systematic gap filling data mining development approaches are required to transform data " tombs" into " golden nuggets" of knowledge. This paper proposes an algorithm for this purpose based on the Incremental Orthogonal Centroid (IOC). Search time for specific data patterns may be enhanced using this algorithm.

关键词： Pipelines

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Implementation of Vocal Tract Length Normalization for Phoneme Recognition on TIMIT Speech Corpus

Implementation of Vocal Tract Length Normalization for Phone...

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2011 International Conference on Information Communication and Management(ICICM 2011)

作者： Jensen Wong Jing Lung Md.Sah Hj.Salam Mohd Shafry Mohd Rahim Abdul Manan Ahmad Department of Computer Graphics ＆ Multimedia Faculty of Computer Science and Information System University Technology Malaysia 81310 UTM Skudai Johor Malaysia

Inter-speaker variability, one of the problems faced in speech recognition system, has caused the performance degradation in recognizing varied speech spoken by different speakers. Vocal Tract Length Normalization （VTLN） method is known to improve the recognition performances by compensating the speech signal using specific warping factor. Experiments are conducted using TIMIT speech corpus and Hidden Markov Model Toolkit （HTK） together with the implementation of VTLN method in order to show improvement in speaker independent phoneme recognition. The results show better recognition performance using Bigram Language Model compared to Unigram Language Model, with Phoneme Error Rate （PER） 28.8% as the best recognition performance for Bigram and PER 38.09% for Unigram. The best warp factor used for normalization in this experiment is 1.40.

关键词： VTLN inter-speaker variability speech signal warp factor phoneme recognition.

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Real-time projection shadow with respect to sun's position in virtal environments

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International Journal of computer science Issues 2011年第6 6-3期8卷 80-84页

作者： Kolivand, Hoshang Amirshakarami, Azam Sunar, Mohd Shahrizal ViCubelab Department of Computer Graphics and Multimedia Faculty Computer Science and Information Systems Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia

This paper proposes a real-time software for outdoor rendering to control the shadow's position with effect of sun's position. The position of sun plays an important rule for outdoor games. Calculation of sun's position, as a result, position and length of shadows require a lot of attention and preciseness. Julian dating is used to calculate the sun's position in the virtual dome. In addition, of computer graphics, building design is another field that this paper contributes on it. To create shadow, projection shadow is proposed. By calculating the sun's position in the specific date, time and location on the earth, shadow is generated. Length and angle of shadow are two parameters measured for building design and both of them are calculated in this real-time application. Therefore, it can be used for teachers to teach some part of physics about earth orbit and it can be used in building design and commercial games in virtual reality systems.

关键词： Orbits

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Self-motion illusions in immersive virtual reality environments

Self-motion illusions in immersive virtual reality environme...

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IEEE Annual International Symposium Virtual Reality

作者： Gerd Bruder Frank Steinicke Phil Wieland Visualization and Computer Graphics Research Group Department of Computer Science University of Münster Germany Psychology Department II University of Münster Germany

Motion perception in immersive virtual reality environments significantly differs from the real world. For example, previous work has shown that users tend to underestimate travel distances in immersive virtual environments (VEs). As a solution to this problem, some researchers propose to scale the mapped virtual camera motion relative to the tracked real-world movement of a user until real and virtual motion appear to match, i. e., real-world movements could be mapped with a larger gain to the VE in order to compensate for the underestimation. Although this approach usually results in more accurate self-motion judgments by users, introducing discrepancies between real and virtual motion can become a problem, in particular, due to misalignments of both worlds and distorted space cognition. In this paper we describe a different approach that introduces apparent self-motion illusions by manipulating optic flow fields during movements in VEs. These manipulations can affect self-motion perception in VEs, but omit a quantitative discrepancy between real and virtual motions. We introduce four illusions and show in experiments that optic flow manipulation can significantly affect users' self-motion judgments. Furthermore, we show that with such manipulation of optic flow fields the underestimation of travel distances can be compensated.

关键词： Visualization Optical sensors Cameras Integrated optics Blindness Optical distortion Detectors

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Visibly accurate model-based binary image compression scheme

Visibly accurate model-based binary image compression scheme

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IEEE International Conference on Signal and Image Processing Applications (ICSIPA)

作者： Saif alZahir Image Processing Graphics and Multimedia Lab Computer Science Department UNBC Prince George BC Canada

In this paper we propose a model-based binary image compression scheme. In this scheme, we merge one-dimensional (1-D) blocks of black pixels of the input binary image with those in consecutive rows into larger blocks using mathematical models that preserve the quality of the image. This process reduces the number of vertices when the image is segmented into rectangles for compression. The top-left and the bottom-right vertices of each generated rectangle are then identified and the coordinates of which are efficiently encoded. The model for merging the blocks was obtained through extracting the data values involving the blocks of various widths and the subjective tolerance of an average viewer. The data values are then plotted on a Cartesian plane and approximated with linear, logarithmic, and polynomial functions. Simulation results show that the images after merging using the proposed model have less number of rectangles without any obvious image distortion and have higher compression ratio those rectangular partitioning methods in the literature.

关键词： Image coding Mathematical model Merging Polynomials Image segmentation Simulation Correlation

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$\hbox{MAWA}^{\ast}$—A Memory-Bounded Anytime Heuristic-Search Algorithm

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IEEE Transactions on Systems, Man, and Cybernetics, Part B (Cybernetics) 2011年第3期41卷 725-735页

作者： Satya Gautam Vadlamudi Sandip Aine Partha Pratim Chakrabarti Department of Computer Science and Engineering Indian Institute of Technology Kharagpur Kharagpur India Mentor Graphics Private Limited San Jose CA USA

This paper presents a heuristic-search algorithm called Memory-bounded Anytime Window A*(MAWA*), which is complete, anytime, and memory bounded. MAWA* uses the window-bounded anytime-search methodology of AWA* as the basic framework and combines it with the memory-bounded A* -like approach to handle restricted memory situations. Simple and efficient versions of MAWA* targeted for tree search have also been presented. Experimental results of the sliding-tile puzzle problem and the traveling-salesman problem show the significant advantages of the proposed algorithm over existing methods.

关键词： Heuristic algorithms Memory management Algorithm design and analysis Cybernetics Search problems Data structures

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Sketch-based rotation editing

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Frontiers of Information Technology & Electronic Engineering 2011年第11期12卷

作者： Yue XIE Wei-wei XU Yi-zhou YU Yan-lin WENG School of Computer Science and Technology Zhejiang University Hangzhou 310027 China Internet Graphics Group Microsoft Research Asia Beijing 100190 China Department of Computer Science University of Illinois at Urbana-Champaign Urbana Illinois 61801 USA

We present a sketch-based rotation editing system for enriching rotational motion in keyframe *** a set of keyframe orientations of a rigid object,the user first edits its angular velocity trajectory by sketching curves,and then the system computes the altered rotational motion by solving a variational curve fitting *** solved rotational motion not only satisfies the orientation constraints at the keyframes,but also fits well the user-specified angular velocity *** system is simple and easy to *** demonstrate its usefulness by adding interesting and realistic rotational details to several keyframe animations.

关键词： Quaternions Keyframe interpolation Animation editing

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Surface membrane based bladder registration for evaluation of accumulated dose during brachytherapy in cervical cancer

Surface membrane based bladder registration for evaluation o...

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IEEE International Symposium on Biomedical Imaging

作者： Karsten Ø. Noe Kari Tanderup Thomas S. Sørensen Department of Computer Science Aarhus University Denmark Computer Graphics Laboratory The Alexandra Institute Denmark Department of Oncology Aarhus University Hospital Denmark Aarhus Universitet Aarhus DK

A new optimisation strategy for surface mesh registration is proposed based on energy minimisation of an elastic surface membrane. The energy term is evaluated in three-dimensional space, optimisation however is performed while constraining the moving surface to a parametrised spherical space of the fixed surface. Optional landmark based matches can be included in the suggested iterative solver. The technique is demonstrated for bladder registration in brachytherapy treatment evaluation of cervical cancer. It holds promise to better estimate the accumulated but unintentional dose delivered to organs at risk.

关键词： Bladder Geometry Three dimensional displays Surface treatment Brachytherapy Springs Optimization

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Magnetic Resonance Based Control of a Robotic Manipulator for Interventions in the Beating Heart

Magnetic Resonance Based Control of a Robotic Manipulator fo...

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2011 IEEE International Conference on Robotics and Automation(2011年IEEE世界机器人与自动化大会 ICRA 2011)

作者： Nikolaos V. Tsekos Johann Lamaury Erol Yeniaras Zhigang Deng Nikhil V. Navkar Dipan J. Shah Karen Chin Medical Robotics Laboratory Department of Computer Science at University of HoustonHoustonTX 77204 Computer Graphics and Interactive Media Lab. Department of Computer ScienceUniversity of HoustonHo Methodist DeBakey Heart & Vascular Center HoustonTX 77030 USA

As a part of an ongoing project, in this paper we introduce the first version of a system which has a novel methodology for Cine (as in cinema) MRI based control of a cardiac robot for beating heart surgeries. The system uses the preoperative planning approach that we developed earlier, and integrates it to the intraoperative algorithms for controlling a robot and tracking some specific landmarks of a highly dynamical surgical field. In particular, our late studies presented herein aim to demonstrate the feasibility of integrating appropriate computational tools to achieve the volumetric image guidance for minimally invasive surgeries in the beating heart. We conceive of the system as practicable for in vitro experiments upon the completion of the first physical prototype, which may pave the way for expansion of the approach for other complex surgeries as well.

关键词： Heart Magnetic resonance imaging Manipulators Surgery Robot kinematics Valves

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Extracting geometric features of aortic valve annulus motion from dynamic MRI for guiding interventions

Extracting geometric features of aortic valve annulus motion...

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IEEE International Symposium on Biomedical Imaging

作者： Nikhil V. Navkar Erol Yeniaras Dipan J. Shah Nikolaos V. Tsekos Zhigang Deng Medical Robotics Laboratory Department of Computer Science University of Houston Houston TX USA Methodist DeBakey Heart & Vascular Center Methodist Hospital Houston TX USA Computer Graphics and Interactive Media Laboratory Department of Computer Science University of Houston Houston TX USA

ISBN: (纸本)9781424441273

Transcatheter aortic valve implant (TAVI) has emerged as a prominent approach for treating aortic stenosis. Success of such implants depends upon the accurate assessment of the geometric features such as the diameter, center and orientation of the aortic valve annulus (AVA). In this paper, we present a method for extracting these geometric features from magnetic resonance images (MRI). The method is based on finding an optimal fit for a circular ring mimicking AVA in the aortic root. Moreover, the presented approach provides dynamic tracking of the AVA in CINE MR images. This approach can be used for preoperative planning of prosthetic valve implantation, as well as for the emerging MRI guided manual, or with robot-assisted, annuloplasty.

关键词： Valves Magnetic resonance imaging Robots Heart Tracking Prosthetics

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