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Real-time reliability prediction for dynamic systems with both deteriorating and unreliable components

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science in china(Series F) 2009年第11期52卷 2234-2246页

作者： XU ZhengGuo1,2, JI YinDong2,3 & ZHOU DongHua1,2? 1 Department of Automation, Tsinghua university, beijing 100084, china 2 Tsinghua National Laboratory for Information science and technology, Tsinghua university, beijing 100084, china 3 Research Institute of Information technology (RIIT), Tsinghua university, beijing 100084, china Department of Automation Tsinghua University Beijing 100084 China Tsinghua National Laboratory for Information science and technology Tsinghua University Beijing 100084 China Research Institute of Information technology (RIIT) Tsinghua University Beijing 100084 China

As an important technology for predictive maintenance, failure prognosis has attracted more and more attentions in recent years. Real-time reliability prediction is one effective solution to failure prognosis. Considering a dynamic system that is composed of normal, deteriorating and unreliable components, this paper proposes an integrated approach to perform real-time reliability prediction for such a class of systems. For a deteriorating component, the degradation is modeled by a time-varying fault process which is a linear or approximately linear function of time. The behavior of an unreliable component is described by a random variable which has two possible values corresponding to the operating and malfunction conditions of this component. The whole proposed approach contains three algorithms. A modified interacting multiple model particle filter is adopted to estimate the dynamic system＇s state variables and the unmeasurable time-varying fault. An exponential smoothing algorithm named the Holt＇s method is used to predict the fault process. In the end, the system＇s reliability is predicted in real time by use of the Monte Carlo strategy. The proposed approach can effectively predict the impending failure of a dynamic system, which is verified by computer simulations based on a three-vessel water tank system.

关键词： reliability failure prognostics dynamic systems fault prediction particle filtering interacting multiple model exponential smoothing,predictive maintenance

Tissue P systems with cell separation: attacking the partition problem

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science china(Information sciences) 2011年第2期54卷 293-304页

作者： ZHANG XingYi1, WANG Shuo2, NIU YunYun2 & PAN LinQiang2 1Key Lab of Intelligent Computing and Signal Processing of Ministry of Education, school of computer science and technology, Anhui university, Hefei 230039, china 2Image Processing and Intelligent Control Key Laboratory of Education Ministry of china, Department of Control science and engineering, Huazhong university of science and technology, Wuhan 430074, china 1. Key Lab of Intelligent Computing and Signal Processing of Ministry of Education School of Computer Science and Technology Anhui University Hefei 230039 China2. Image Processing and Intelligent Control Key Laboratory of Education Ministry of China Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Tissue P systems are distributed parallel and non-deterministic computing models in the framework of membrane computing, which are inspired by intercellular communication and cooperation between neurons. Recently, cell separation is introduced into tissue P systems, which enables systems to generate an exponential workspace in a polynomial time. In this work, the computational power of tissue P systems with cell separation is investigated. Specifically, a uniform family of tissue P systems with cell separation is constructed for effciently solving a well-known NP-complete problem, the partition problem.

关键词： membrane computing tissue P system cell separation partition problem

Web Application Comprehension Based on Dependence Analysis

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Wuhan university Journal of Natural sciences 2004年第5期9卷 731-734页

作者： WU Jun-hua 1,2 , XU Bao-wen 1 , JIANG Ji-xiang 1 1.Department of computer science and engineering, Southeast university, Nanjing 210096, Jiangsu, china 2.College of computer science and engineering, Nanjing university of technology, Nanjing 210009, Jiangsu , china Southeast university Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***) Najing university of technology College of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.41156.37) (ISNI:***) Southeast university Department of Computer Science and Engineering Nanjing Jiangsu China (GRID:grid.263826.b) (ISNI:***)

Many research indicate a lot of money and time are spent on maintaining and modifying program delivered. So the policies to support program comprehension are very important. Program comprehension is a crucial and difficult task. Insufficient design, illogical code structure, short documents will enhance the comprehensive difficulty. Developing Web application is usually a process with quick implementation and delivery. In addition, generally a Web application is coded by combining mark language statements with some embedded applets. Such programming mode affects comprehension of Web applications disadvantageously. This paper proposes a method to improving understanding Web by dependence analysis and slice technology. Key words Web application comprehension - program dependence - hyper graph - pogram slicing CLC number TP 311 Foundation item: Supported in part by the Young Scientist’s Fund of NSFC (60373066, 60303024). National Grand Fundamental Research 973 Program of china (2002CB312000) and National Research Foundation for the Doctoral Program of Higher Education of chinaBiography: WU Jun-hua (1965-), female, Ph. D. research direction: software engineering.

关键词： Web application comprehension program dependence hyper graph pogram slicing

TREE DECOMPOSITIONS OF MULTIGRAPHS

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Systems science and Mathematical sciences 1999年第3期12卷 231-237页

作者： SHI Minyong(Department of computer science and technology,beijing Broadcasting Institute, beijing 100024, china) 北京广播学院计算机系北京 100024

For a graph G, if E(G) can be partitioned into several pairwise disjoint sets as{E1 , E2,...,El } such that the subgraph induced by Ei is a tree of order ki ) (i = 1, 2,... , l),then G is said to have a {k1, k2, ..., kl }-tree-decomposition, denoted by { k1, k2 ,..., Kl } *** k 1 and l 0, a collection (k,l) is the set of multigraphs such that G e Q(k,l)if and only if e(G) = k(G - 1) - l and (H) max{(k - 1)(H - 1),k(H -1) -l}for any subgraph H of G. We Prove that (1) If k 2,0 l 3 and G Q(k,l) oforder + 1, then {n,n,...,n -- l} E G. (2) If 2 and G (k,2) of ordern 3, then {n,n, ...,n,n-- 2} E G and {n,n,.. -1,n - 1} G. (3) If 3 andG g(k,3) of order n 4, then {n, n,... n,n-- 3} G ) {n,n,.., n,n-- 1,n -- 2} Gand {n,n,... n,n -- 1,n -- 1,n -- 1} G.

关键词： Tree decomposition (k l) graphs Pk-graph maximal planar bipartitegraph maximal planar graph

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

Feedback image encryption algorithm with compound chaotic stream cipher based on perturbation

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science china(Information sciences) 2010年第1期53卷 191-202页

作者： TONG XiaoJun1 & CUI MingGen2 1school of computer science and technology, Harbin Institute of technology, Weihai 264209, china 2school of science, Harbin Institute of technology, Weihai 264209, china 1. school of computer science and technology Harbin Institute of Technology Weihai 264209 China2. School of Science Harbin Institute of Technology Weihai 264209 China

In this paper, two new one-dimensional chaotic functions are designed using Devaney chaotic definition. And a dynamically shifting compound chaotic function is constructed based on the two new one-dimensional chaotic functions. The properties of compound chaotic functions are also proved. A new feedback image encryption algorithm is designed using the new compound chaos and an image pixel permutation, 3D baker scheme is described in detail. In the scheme, a new dynamic block dividing the 3D baker is put forward using the compound chaotic map, and the key space expands. In order to produce avalanche effect and sensitivity of cipher to plaintext, the round times are designed to control the cycle. The entropy analysis, difference analysis, weak-key analysis, statistical analysis, cipher random analysis, and cipher sensibility analysis depending on key and plaintext are introduced to test the security of the new scheme of image encryption. The tests show that the image encryption method passes the random tests of NIST FIPS 140-2(2001) and SP 800-22 standards. This paper also solves the problem of short periods and low precision of one-dimensional chaotic function by perturbation.

关键词： compound chaos stream cipher feedback image encryption 3D baker perturbation

A Hybrid of Theorems of Goldbach and Piatetski-Shapiro

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Chinese Annals of Mathematics,Series B 2006年第3期27卷 341-352页

作者： Xianmeng MENG Mingqiang WANG school of computer science and technology, Shandong university, Jinan 250100, china Department of Statistics and Mathematics, Shandong Finance Institute, Jinan 250014, china. school of computer science and technology, Shandong university, Jinan 250100, china Department of Mathematics, Qufu Normal university, Qufu 273165, Shandong, china. school of computer science and technology Shandong University Jinan 250100 China Department of Statistics and Mathematics Shandong Finance Institute Jinan 250014 China Department of Mathematics Qufu Normal University Qufu 273165 Shandong China

It is proved that for almost all sufficiently large even integers n, the prime variable equation n = p1 ＋ p2, p1 ∈ Pγ is solvable, with 13/15 〈γ≤ 1, where Pγ = {p ｜p = [m^1/γ], for integer m and prime p} is t... 详细信息

关键词： Circle method Sieve method Goldbach problem

An Aggregation Composition Compensation Method Based on Paired Net

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International Journal of Automation and computing 2012年第5期9卷 530-538页

作者： Xiao-Yong Mei 1,2 Yi-Yan Fan 2 Chang-Qin Huang 3 Ai-Jun Jiang 1 Shi-Xian Li 1 1 school of Information science and technology,Sun Yat-sen university,Guangzhou 510006,china 2.school of computer science and technology,Hunan university of Arts and science,Changde 415000,china 3 Department of Electrical engineering and computer science,university of California,Irvine,CA,92697,USA 1. school of Information science and technology Sun Yat-sen University Guangzhou 510006 China 2. school of computer science and technology Hunan University of Arts and Science Changde 415000 China 3. Department of Electrical engineering and computer science University of California Irvine CA 92697 USA

With regard to the failure and cancellation of business logic of web services composition(WSC),this paper propose a novel web services transaction compensation mechanism based on paired net which can dynamically establish agile compensation-triggered process(CSCP-Nets),and satisfy prospective compensation *** related execution semantics of five usual composition compensation patterns based on paired net are analyzed in the situations of successful execution,failure compensation and failure *** net based application of trip reservation process(TRP) shows that it is feasible.

关键词： Web services composition failure handling composition compensation execution semantic analysis paired net

Retransmission or redundancy:Transmission reliability study in wireless sensor networks

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science china(Information sciences) 2012年第4期55卷 737-746页

作者： WEN Hao 1,LIN Chuang 1,REN FengYuan 1,ZHOU Jia 1,YUE Yao 2 & HUANG XiaoMeng 1 1 Department of computer science and technology,Tsinghua university,beijing 100084,china 2 Department of computer science,Cornell university,Upson Hall 4161,NY,USA 1. Department of computer science and technology Tsinghua University Beijing 100084 China2. Department of Computer Science Cornell University Upson Hall NY 4161 USA

As an application-driven network,wireless sensor network generally requires data reliability to maintain detection and response *** two approaches,namely,retransmission and redundancy,have been proposed to enhance data reliability,the theoretical work is required to evaluate their impact on transmission reliability and energy *** this paper,we offer a comprehensive theoretical study on packet arrival probability and average energy consumption for both *** analysis and simulations indicate that when loss probabilities remain low or moderate,erasure coding,a typical redundancy-based scheme,is more energy efficient than *** also demonstrate that the resistance capability of erasure coding against packet loss weakens as the hop number increases,which motivates us to propose two improved mechanism based on the idea of the loss detection and the loss ***,the simulation results carried out using TOSSIM verify the performance of different mechanisms both in the chain topology and the tree topology.

关键词： reliability energy efficiency retransmission redundancy erasure coding