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IEEE Region 10 International Conference TENCON

作者： Kampol Woradit Lunchakorn Wuttisittikulkij Siwaruk Siwamogsatham Department of Electrical Engineering Chulalongkom University Bangkok Thailand Telecommunications and Network Research and Development Division National Electronics and Computer Technology Center Bangkok Thailand

This paper describes how to construct a class of spaces-frequency (SF) codes by mapping the super-orthogonal space-time trellis (SOSTT) codes across OFDM subcarriers. Two mapping methods are employed: conventional repetition mapping and the proposed mapping methods with the design criteria of achieving full diversity including spatial and frequency at the maximum possible transmission rate. The proposed mapping method appears to outperform the conventional mapping counterpart with respect to coding gain when constructing the SF codes mapped from SOSTT codes. Simulation results show the performance gain of 0.5-3 dB under frequency-selective fading channels. In addition, the constructed SF codes mapped with both mapping methods are compared to the existing commonly known SF codes, i.e. the space-time trellis (STT) codes mapped with conventional mapping method. Apparently the SOSTT codes are superior to the STT codes in single-carrier narrowband wireless channel, the mapped SOSTT codes do not offer the same advantage over the mapped STT codes under the severely-frequency-selective fading channel when the codes having large number of states. Nevertheless, some performance improvement is observed for codes with small number of states.

关键词： Convolutional codes Fading Frequency diversity OFDM Narrowband Propagation losses US Department of Transportation Wideband Design methodology Performance gain

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Study of Multi media Streams Dynamic Rate Control Based on Fuzzy Adaptive PID

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The Journal of China Universities of Posts and Telecommunications 2005年第4期12卷 75-79页

作者： SUN Yan-fei ZHANG Shun-yi SHI Jin WANG Jiang-tao Jiangsu Province Engineering Research Center of Telecommunication dr Network Technology Nanjing University of Posts and TelecommunicationsNanjing 210003 P.y. China State Key Laboratory of Novel Software Technology Nanjing University Nanjing 210093 P. R. China Department of Computer Science and Technology Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China

A Multimedia streams dynamic rate control algorithm based on Fuzzy adaptive PID （MFPID） has been proposed to implement multimedia streams＇ end sending rate on-line self-regulating and smoothing, and to track system resources in time, so that it can avoid system＇s regulating oscillation and guarantee system＇s stability. And, some work has been done to analyze adaptive session model of multimedia streams, to implement future available bandwidth estimation of IP network, to achieve PID parameters＇ on-line self-tuning by fuzzy controlling. Simulation validated the theoretical results of MFPID.

关键词： multimedia transmission dynamic end sending rate PID adaptive regulating fuzzy parameter self-tuning

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Study of Secure Complicated Information System Architecture Model

Study of Secure Complicated Information System Architecture ...

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International Conference on Semantics, Knowledge and Grid (SKG)

作者： Kun Wang Ruidan Su Zengxin Li Zhen Cai Lihua Zhou Key Laboratory of Computer Network and Information Security of the Ministry of Education Xidian University Xi'an China National Info Security Engineering and Technology Research Center Beijing China

Complicated information system (CIS) contains many inhomogeneous applications which require security, interoperability, extensibility. The paper presents a secure CIS architecture model to conduct the construction or reconstruction of CIS. Using layered method, it divides CIS into modules and reduces system complexity. Web service technology is widely adopted in layers to fulfill interoperability and extensibility. It uses encryption support layer, security protection and reliability support layer to guarantee system security and stability in different aspects. It uses system management layer to make CIS administrable. It suits highly security-critical environment such as government and bank. Been properly simplified, it can be applied to relative simple information system too.

关键词： Information systems Information security Computational Intelligence Society Communication system security National security Electronic government Operating systems Protocols Communication standards computer security

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A Mathematical Approach to Disaster Recovery Planning

A Mathematical Approach to Disaster Recovery Planning

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International Conference on Semantics, Knowledge and Grid (SKG)

作者： Kun Wang Zhonghai Yin Feng Yuan Lihua Zhou Key Laboratory of Computer Network and Information Security of the Ministry of Education Xidian University Xi'an China National Info Security Engineering and Technology Research Center Beijing China

It is crucial for highly security-critical information systems to accurately control the disaster recovery activities. Using optimization theory, we present a disaster recovery planning mathematical model. The model uses mathematical method to express diverse entities in information and disaster recovery system such as applications, facilities, resources, sub disaster recovery plans, budget, etc. It classifies various resources according to their utilization and payment, and identifies the significance of applications and the conflicts among sub disaster recovery plans. Through expressing relationships among applications, facilities, resources and sub plans, this model selects the best set of sub plans. This model has less subjective parameter and can evaluate disaster recovery planning objectively and quantitatively.

关键词： Mathematical model Testing Information security Information systems Control systems Risk management technology planning Laboratories computer networks computer science education

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A Disaster Recovery System Model in an E-government System

A Disaster Recovery System Model in an E-government System

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IEEE International Conference on Parallel and Distributed Computing, Applications and Technologies (PDCAT)

作者： Kun Wang Lihua Zhou Zhen Cai Zengxin Li Key Laboratory of Computer Network and Information Security of the Ministry of Education Xidian University Xi'an China National Info Security Engineering and Technology Research Center Beijing China

We present a Robust Disaster Recovery System Model (RDRSM) for highly security-critical systems to realize continuous service. Through strengthening safe communication ability, RDRSM guarantees secure and reliable command on disaster recovery. It uses selfsupervision function to monitor the integrality and security of system itself. Through GIS, this model makes disaster recovery system easier to use, manage and maintain. RDRSM possesses features of security, robustness and controllability and can be applied to environments such as e-government and bank. This model successfully conducted the construction of an important e-government disaster recovery system, which verified its feasibility and the significance of its components, such as disaster recovery planning, system supervision and robust communication support.

关键词： Electronic government Robustness Communication system security Stability Disaster management computer networks Information security Monitoring Geographic Information Systems Protection

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Power splitters for ultralow refractive index metallic nanostructures waveguides

Power splitters for ultralow refractive index metallic nanos...

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SBMO/IEEE MTT-S International Conference on Microwave and Optoelectronics (IMOC)

作者： V.F. Rodriguez-Esquerre M. Koshiba H.E. Hernandez-Figueroa C.E. Rubio-Mercedes Division of Media and Network Technologies Hokkaido University Japan Department of Microwave and Optics School of Electrical and Computer Engineering State University of Campinas-UNICAMP Brazil Center of Exact Sciences and Technology State University of Mato Grosso do Sul Brazil

We investigated power splitters in air core waveguides with a metallic photonic crystal cladding. The mechanism of propagation in these guides is the total external reflection. The cladding is formed by a periodic arrangement of metallic wires on square or triangular lattices. Power splitters can be designed by modifying the geometry at the splitting region by introducing a reflecting structure in order to increase the transmission coefficient. Some splitters based on these structures are analyzed by an efficient frequency domain finite element approach.

关键词： Refractive index Nanostructures Optical waveguides Lattices Silver Copper Gold Electromagnetic waveguides Optical refraction Optical variables control

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Clock error model for single point two-channel linked network probe system

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Dalian Ligong Daxue Xuebao/Journal of Dalian University of technology 2005年第SUPPL.期45卷 S55-S58页

作者： Gong, Jian Xu, Jia-Ling Jiangsu Province Key Laboratory of Computer Network Technology Nanjing 210096 China East China Regional Network Center of CERNET Nanjing 210096 China Computer Science and Engineering Dept. Southeast University Nanjing 210096 China

network measurement technology has been one of the hot topics of nowadays Internet technology research. Clock error is the main and direct source of errors in network measurement. Traditionally, the research works on network measurement merely focusing on how to rectify the result and improve clock precision, but neglect the inevitable clock error's effect on measurement result. While this situation is inadaptable for quantified description of time error in distributed cooperative measurement, this paper, integrating the error and precision analysis theory and taking into consideration the features of network passive measurement, represents a clock error model for single point two-channel linked network probe system, and brings in uncertainty to quantificational description of precision and rationality of measurement result.

关键词： Internet

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Challenges of molecular nanotechnology for space exploration

Challenges of molecular nanotechnology for space exploration

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Space 2005

作者： McKendree, Thomas L. Freitas Jr., Robert A. Globus, Al Levit, M. Creon Sherrill, C. David Li, Mo Merkle, Ralph C. Raytheon Network Centric Systems Fullerton CA 92646-3310 United States Institute of Molecular Manufacturing 555 Bryant Street Palo Alto CA 94301 United States Computer Sciences Corporation Evolvable Systems Group Moffett Field MS 269-3 CA 94035 United States NASA Ames Research Center Advanced Supercomputing Division Moffett Field MS T27-A CA 94035-1000 United States Georgia Institute of Technology Chemistry and Biochemistry 770 State Street Atlanta GA 30332-0400 United States Georgia Institute of Technology Materials Science and Engineering 771 Ferst Drive NW Atlanta GA 30332-0245 United States Georgia Institute of Technology College of Computing 801 Atlantic Dr Atlanta GA 30332-0280 United States

ISBN: (纸本)1563477386

Molecular nanotechnology is the future capability to design and build systems to atomic precisions. This paper motivates the desire of molecular nanotechnology for space exploration with a review of potential benefits, and reviews relevant progress to date for molecular nanotechnology. It provides a framework of challenges that need to be resolved before molecular nanotechnology can be applied to space systems, with discussion on addressing those challenges. The primary focus is in the area of developing tools for automated design of molecular components, using molecular connector components as an example, and in developing tools for generating reaction pathways to fabricate molecular components that can integrate with tools for developing molecular components. The secondary focus is issues for the molecular fabrication system, including integration with the design of end product space systems. © 2005 by McKendree et al. Published by the American Institute of Aeronautics and Astronautics, Inc.

关键词： Space research

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Semantic analysis of basketball video using motion information

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Lecture Notes in computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 2004年 3331卷 65-72页

作者： Liu, Song Yi, Haoran Chia, Liang-Tien Rajan, Deepu Chan, Syin Center for Multimedia and Network Technology School of Computer Engineering Nanyang Technological University Singapore 639798 Singapore

This paper presents a new method for extracting semantic information from basketball video. Our approach consists of three stages: shot and scene boundary detection, scene classification and semantic video analysis for event detection. The scene boundary detection algorithm is based on both visual and motion prediction information. After the shot and scene boundary detection, a set of visual and motion features are extracted from scene or shot. The motion features, describing the total motion, camera motion and object motion within the scene respectively, are computed from the motion vector of the compressed video using an iterative algorithm with robust outlier rejection. Finally, the extracted features are used to differentiate offensive/defensive activities in the scenes. By analyzing the offensive/defensive activities, the positions of potential semantic events, such as foul and goal, are located. Experimental results demonstrate the effectiveness of the proposed method. © Springer-Verlag Berlin Heidelberg 2004.

关键词： Iterative methods

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VRules: An effective association-based classifier for videos

VRules: An effective association-based classifier for videos

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MMDB 2004: Proceedings of the Second ACM International Workshop on Multimedia Databases

作者： Chen, Ling Bhowmick, Sourav S. Chia, Liang-Tien Center for Multimedia and Network Technology School of Computer Engineering Nanyang Technological University Singapore 639798

ISBN: (纸本)1581139756

Video classification is an important step towards multimedia understanding. Most state-of-the-art approaches which apply HMM to capture the temporal information of videos have the limitation by assuming that the current state of a video depends only on the immediate previous state. Nevertheless, this assumption may not hold for videos of various categories. In this paper, we present an effective video classifier which employs the association rule mining technique to discover the actual dependence relationship between video states. The discriminatory state transition patterns mined from different video categories are then used to perform classification. Besides capturing the association between states in the time space, we also capture the association between low-level features in spatial dimension to further distinguish the semantics of videos. Experimental results show that the performance of our association rule based classifier is quite promising. Copyright 2004 ACM.

关键词： Multimedia systems

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