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Linear low-rank approximation and nonlinear dimensionality reduction

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science China Mathematics 2004年第6期47卷 908-920页

作者： ZHANG Zhenyue & ZHA Hongyuan department of Mathematics, Zhejiang university, Yuquan Campus, Hangzhou 310027, China department of computer science and engineering, The Pennsylvania State university, university Park, PA 16802, U.S.A. 1. department of Mathematics Zhejiang University Yuquan Campus 310027 Hangzhou China 2. department of computer science and engineering The Pennsylvania State University 16802 University Park PA USA

We present our recent work on both linear and nonlinear data reduction methods and algorithms: for the linear case we discuss results on structure analysis of SVD of columnpartitioned matrices and sparse low-rank approximation; for the nonlinear case we investigate methods for nonlinear dimensionality reduction and manifold learning. The problems we address have attracted great deal of interest in data mining and machine learning.

关键词： singular value decomposition low-rank approximation sparse matrix nonlinear dimensionality reduction principal manifold subspace alignment data mining

Two Generic Frameworks of Multiple Viewpoints Oriented Requirements Method and Their Comparison

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Wuhan university Journal of Natural sciences 2001年第Z1期6卷 313-319页

作者： Song Qiang, He Yan xiang, Huang Qian School of computer science, State Key Laboratory of software engineering, Wuhan university, Wuhan 430072, China School of computer science State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 China

Traditional requirements method has some problems when it is used for large distributed systems. Multiple viewpoints oriented requirements method (MVORM) is a new method for resolving these problems. This paper develops two generic formal frameworks of MVORM, framework based on refinement relation (FBRR) and framework based on implementation relation (FBIR). They are generic, because no assumptions are made about the development process or the formal description languages to be used. Three kinds of specification relations and three kinds of specification transformations are discussed over FBIR and FBRR. This paper also compares the equivalence between FBIR and FBRR. We point out that an equivalent FBIR can be found for any FBRR, but reverse transformation is not always possible. We think FBIR is better than FBRR on most cases.

关键词： multiple viewpoints oriented requirements method framework based on refinement relation framework based on implementation relation refinement relation implementation relation

Building a next generation Internet with source address validation architecture

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science in China(Series F) 2008年第11期51卷 1681-1691页

作者： WU JianPing1,3,REN Gang1,3 & LI Xing2,3 1 department of computer science,Tsinghua university,Beijing 100084,China 2 department of Electronic engineering,Tsinghua university,Beijing 100084,China 3 Tsinghua National Laboratory for Information science and Technology(TNList) ,Beijing 100084,China department of computer science Tsinghua University Beijing 100084 China department of Electronic engineering Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information science and Technology (TNList) Beijing 100084 China

The IP packet forwarding of current Internet is mainly destination based. In the forwarding process, the source IP address is not checked in most *** causes serious security, management and accounting problems. Based on the drastically increased IPv6 address space, a ＂source address validation architecture＂（SAVA） is proposed in this paper, which can guarantee that every packet received and forwarded holds an authenticated source IP address. The design goals of the architecture are lightweight, loose coupling, ＂multi-fence support＂ and incremental deployment. This paper discusses the design and implementation for the architecture, including inter-AS, intra-AS and local subnet. The performance and scalability of SAVA are described. This architecture is deployed into the CNGI-CERNET2 infrastructure a large-scale native IPv6 backbone network of the China Next Generation Internet project. We believe that the SAVA will help the transition to a new, more secure and dependable Internet.

关键词： IP source address validation network architecture network security

Solving A Kind of High Complexity Multi-Objective Problems by A Fast Algorithm

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Wuhan university Journal of Natural sciences 2003年第S1期8卷 183-188页

作者： Zeng San-you, Ding Li-xin, Kang Li-shandepartment of computer science,China university of Geosciences, Wuhan 430074, Hubei, China department of computer science, Zhuzhou Institute of Technology , Zhuzhou 412008, Hunan, China State Key Laboratory of software engineering, Wuhan university, Wuhan 430072, Hubei, China China university of Geosciences Department of Computer Science Wuhan Hubei China (GRID:grid.162107.3) (ISNI:***) Zhuzhou Institute of Technology Department of Computer Science Zhuzhou Hunan China (GRID:grid.162107.3) China university of Geosciences Department of Computer Science Wuhan Hubei China (GRID:grid.162107.3) (ISNI:***) Wuhan university State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

A fast algorithm is proposed to solve a kind of high complexity multi-objective problems in this paper. It takes advantages of both the orthogonal design method to search evenly, and the statistical optimal method to speed up the computation. It is very suitable for solving high complexity problems, and quickly yields solutions which converge to the Pareto-optimal set with high precision and uniform distribution. Some complicated multi-objective problems are solved by the algorithm and the results show that the algorithm is not only fast but also superior to other MOGAS and MOEAs, such as the currently efficient algorithm SPEA, in terms of the precision, quantity and distribution of solutions.

关键词： evolutionary algorithms orthogonal design multi-objective optimization Pareto-optimal set

Performance Modeling and Approximate Analysis of Multiserver Multiqueue Systems with Poisson and Self-similar Arrivals

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Journal of university of science and Technology Beijing 2001年第2期8卷 145-151页

作者： Zhiguang Shan, Chuang Lin, Yang Yang, Yan Wang (Information engineering School, university of science and Technology Beijing, Beijing 100083, China) (department of computer science and Technology, Tsinghua university, Beijing 100084, China) Univ Sci & Technol Beijing Informat Engn Sch Beijing 100083 Peoples R China Tsinghua Univ Dept Comp Sci & Technol Beijing 100084 Peoples R China

The problem of state space explosion is still ran outstanding challenge in Markovian performance analysis for multiserver multiqueue (MSMQ) systems. The system behavior of a MSMQ system is described using stochastic high-level Petri net (SHLPN) models, and an approximate performance analysis technique is proposed based on decomposition and refinement methods as well as iteration technique. A real MSMQ system, Web-server cluster, is investigated. The performance of an integrated scheme of request dispatching and scheduling is analyzed with both Poisson and self-similar request arrivals. The study shows that the approximate analysis technique significantly reduces the complexity of the model solution and is also efficient for accuracy of numerical results.

关键词： multiserver multiqueue (MSMQ) system Web-server cluster performance analysis stochastic high-level Petri net (SHLPN) request dispatching request scheduling

A Routing Algorithm for Distributed Optimal Double Loop computer Networks

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Journal of Systems engineering and Electronics 1994年第1期5卷 37-43页

作者： Li Layuan(department of Electrical engineering and computer science.Wuhan university of Water Transportation, Wuhan 430063, P. R. China) department of Electrical engineering and computer science Wuhan University of Water Transportation Wuhan 430063 P.R. China

A routing algorithm for distributed optimal double loop computer networks is proposed and analyzed. In this paper, the routing algorithm rule is described, and the procedures realizing the algorithm are given. The proposed algorithm is shown to be optimal and robust for optimal double loop. In the absence of failures,the algorithm can send a packet along the shortest path to destination; when there are failures,the packet can bypasss failed nodes and links.

关键词： computer networks Double loop Routing algorithm

Minimal regular 2-graphs and applications

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science China Mathematics 2006年第2期49卷 158-172页

作者： FAN Hongbing, LIU Guizhen & LIU Jiping department of Physics and computer science, Wilfrid Laurier university, Waterloo, ON., N2L 3C5 Canada School of Mathematics and System science, Shandong university, Jinan 250100, China department of Mathematics and computer science, university of Lethbridge, Lethbridge, AB., T1K 3M4, Canada 1. department of Physics and computer science Wilfrid Laurier University Waterloo ON. N2L 3C5 Canada 2. School of Mathematics and System science Shandong University Jinan 250100 China 3. department of Mathematics and computer science University of Lethbridge Lethbridge AB. T1K 3M4 Canada

A 2-graph is a hypergraph with edge sizes of at most two. A regular 2-graph is said to be minimal if it does not contain a proper regular factor. Let f2(n) be the maximum value of degrees over all minimal regular 2-graphs of n vertices. In this paper, we provide a structure property of minimal regular 2-graphs, and consequently, prove that f2(n) = n+3-i/3, where 1 ≤ i ≤ 6, i ≡ n (mod 6) and n ≥ 7, which solves a conjecture posed by Fan, Liu, Wu and Wong. As applications in graph theory, we are able to characterize unfactorable regular graphs and provide the best possible factor existence theorem on degree conditions. Moreover, fa(n) and the minimal 2-graphs can be used in the universal switch box designs, which originally motivated this study.

关键词： graph regular factor 2-graph switch box design.

Deterministic secure quantum communication without unitary operation based on high-dimensional entanglement swapping

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science China(Information sciences) 2012年第2期55卷 360-367页

作者： LIU ZhiHao1,CHEN HanWu1,LIU WenJie2,XU Juan1 & LI ZhiQiang3 1School of computer science and engineering,Southeast university,Nanjing 211189,China 2School of computer and software,Nanjing university of Information science & Technology,Nanjing 210044,China 3College of Information engineering,Yangzhou university,Yangzhou 225009,China 1. School of computer science and engineering Southeast University Nanjing 211189 China2. School of Computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China3. College of Information Engineering Yangzhou University Yangzhou 225009 China

By analysis of the basic properties of entanglement swapping of high-dimensional Bell states,a universal and general deterministic secure quantum communication(DSQC)protocol is proposed,in which unitary operation is not *** making use of the results of high-dimensional Bell measurement,the sender and the receiver can encode and decode the message respectively by performing the modular addition and *** mutually complementary bases are constructed;and according to the property of mutual complement,a method for checking security of the high-dimensional quantum channel is put *** common attack strategies are analyzed,and the corresponding error rates are *** the upper bound of the threshold of error rate is deduced.

关键词： deterministic secure quantum communication high-dimensional Bell state entanglement swap-ping high-dimensional Bell measurement

Video-based facial animation with detailed appearance texture

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Progress in Natural science:Materials International 2006年第3期16卷 297-306页

作者： WANG Jin, SUN Hanqiu and PENG Qunsheng (department of computer science & Technology, Xuzhou Normal university, Xuzhou 221009, China State Key Laboratory of CAD & CG, Zhejiang university, Zhejiang 310027, China department of computer science & engineering, CUHK Shatin, N.T., Hong Kong) [a]department of computer science & Technology Xuzhou China [b]State Key Laboratory of CAD & CG Zhejiang University Zhejiang China [c]department of computer science & engineering CHUK shatin N.T. Hong Kong

Facial shape transformation described by facial animation parameters (FAPs) involves the dynamic movement or deformation of eyes, brows, mouth, and lips, while detailed facial appearance concerns the facial textures such as creases, wrinkles, etc. Video-based facial animation exhibits not only facial shape transformation but also detailed appearance updates. In this paper, a novel algorithm for effectively extracting FAPs from video is proposed. Our system adopts the ICA-enforced direct appearance model (DAM) to track faces from video sequences; and then, FAPs are extracted from every frame of the video based on an extended model of Wincandidate 3.1. Facial appearance details are transformed from each frame by mapping an expression ratio image to the original image. We adopt wavelet to synthesize expressive details by combining the low-frequency signals of the original face and high-frequency signals of the expressive face from each frame of the video. Experimental results show that our proposed algorithm is suitable for reproducing realistic, expressive facial animations.

关键词： image based rendering facial animation texture transform.