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Journal of Systems Engineering and Electronics 2002年第4期13卷 73-78页

作者： Li Layuan & Li Chunlin department of computer science, wuhan university of technology, wuhan 430063, P. R. China department of computer science Wuhan University of Technology Wuhan 430063 P. R. China

In recent years, QoS multicast routing has continued to be a very important research topic in the areas of networks. This paper presents a heuristic algorithm for the QoS multicast routing (HAQMR). This heuristic algorithm deals with delay and bandwidth constraints and has low cost. The HAQMR attempts to significantly reduce the overhead for constructing a multicast tree, the proof for correctness of the HAQMR is given, and the performance of the HAQMR is evaluated by simulations. The study shows that HAQMR provides an available approach to QoS multicast routing.

关键词： Heuristic QoS Multicast QoS constraints QoS routing.

PEM:a lightweight program memory encryption mechanism for embedded processor

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 77-84页

作者： HUO Wen-jie,LIU Zheng-lin,zou Xue-cheng department of Electronics of science and technology,Huazhong university of science and technology,wuhan 430074,China department of Electronics of science and technology Huazhong University of Science and Technology Wuhan 430074 China

Application of embedded systems is faced with multiple threats against security. To solve this problem, this article proposes a new program memory encryption mechanism （PEM） to enhance the security of embedded processor. The new mechanism encrypts all the programs via a secure cache structure. It not only caches the instructions read from the off-chip memory, but also stores the pad values used to encrypt the plaintext. It effectively accelerates encryption and reduces the performance overhead. Besides the encryption, PEM also monitors the program modifications and reset behaviors to reduce the risk of vicious tamper. The experiment indicates that PEM has an average of 2.3 % performance improvement and results in a 25.71% power reduction in the write-back stage. The new scheme offers a good balance between performance and security. It is fully practicable for embedded processor.

关键词： embedded processor memory encryption advanced encryption standard (AES) secure cache hardware protection

A Recovery Algorithm for Self-Stabilizing Communication Protocols

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Journal of Systems Engineering and Electronics 2000年第1期11卷 38-46页

作者： Li Layuan & Li Chunlin (department of computer science & technology, wuhan nansportation university, 430063, P. R. China) department of computer science & technology Wuhan Transportation University 430063 P. R. China

This paper presents a recovery algorithm for self-stabilizing communication protocols. It first describes some concepts and a formal description method for the algorithm. Then it proposes the algorithm procedures, proves its correctness and analyses its complexity. Finally, it also verifies the availability and efficiency of the algorithm by illustrating an example protocol with multi-processes.

关键词： computer networks Communication protocols Recovery algorithm Self-stabilization Multimedia communication networks.

A Cognitive science Framework for the Analysis of Knowledge-Based Systems

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Journal of Systems Engineering and Electronics 1994年第2期5卷 60-67页

作者： Feng Shan (department of Automatic Control Engineering, Huazhong university of science and technology, wuhan,Hubei, 430074 PRC) department of Automatic Control Engineering Huazhong University of Science and Technology Wuhan Hubei 430074 PRC

The paper presents a cognitive science framework for the analysis of knowledge-based systems,including people, media. simulation and expert systems, resulting in a practical model for the procedures ofknowledge engineering. Starting with the construct of a social organization model driven by anticipationand thed differentiating this into pesonal scientists with diverse relations to people and their internal andexternal communication, it provides powerful and general model of society. people, and the roles of peoplein society. This model extends naturally ic the role of conventional media in the knowledge processes ofsociety and the new roles of computer-based simulation and expert systems. In particular it provides amodel of knowledge transfer that enables the processes of knowledge engineering to be analyzed andautomated.

关键词： Cognitive modeling Knowledge-based systems Knowledge engineering Communal scientist Media.

Search　Algorithm　for　Determining　the　Range　of　the　Possible　Collision　of　Conver　Polygons

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Journal of Systems Engineering and Electronics 1996年第3期7卷 31-42页

作者： Li Qinghua(department of computer science and EngineeringHuazhong university of science technology, wuhan, 430074, P. R. China) department of computer science and Engineering Huazhong university of science technology Wuhan 430074 P. R. China

Let P=(po, p1,..., pn-1 ) and Q=(qo,q1..., qm-1) be two arbitrary convex polygonsin plane. In this paper, the author studies the problems of how to quickly determine their possiblecollision range and movable range. In the paper, a new sufficient and necessary condition for decidingpossible collision is proposed,and the basic characters of the oblique supporting lines are investigated,and on these grounds the problem to determine the possible collision range is transformed into thatof searching the supporting points on the sets of convex polygon vertexs. Using the strategy ofsearching simultaneously the sets of vertexes of P and Q, the author constructs the fast algorithmfor finding the supporting points, the time-complexity of which is O(log2(m + n)). Based on theseresults, the algorithms to quickly determine the range are given, which possess the time-complexityof O(log2(m+n)).

关键词： Possible collision Ranges of possible and impossible collision Oblique supporting line,Supporting points.

An Automatic Testing System of Scheduling Strategies in Real-Time UNIX

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Journal of Systems Engineering and Electronics 2001年第2期12卷 59-62页

作者： Qin Xiao, Pang Liping & Han Zongfen department of computer science, Huazhong university of science and technology, wuhan 430074, P. R. China department of computer science Huazhong University of Science and Technology Wuhan 430074 P. R. China

This paper proposes a formal model of the automatic testing system for scheduling strategies in real-time UNIX and describes the algorithm of the key part of the system. The model of the system is an important technology of the automatization of software development. According to the model presented in the paper, many different kinds of automatic testing systems can be designed and developed easily. At the end of the paper, the prototype proves the feasibility of the model and design.

关键词： Algorithms Automatic testing Real time systems Scheduling Software prototyping

A NOTE ON THE DIPERNA-LIONS FLOWS

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Acta Mathematica Scientia 2011年第5期31卷 1719-1724页

作者：刘昕黄文亮 School of computer science and technology Huazhong University of Science and Technology department of Mathematics East China University of Science and Technology

In this note, we give a short proof for the DiPerna-Lions flows associated to ODEs following the method of Crippa and De Lellis [3]. More precisely, assume that [divb] ∈ Ll∞oc（Rd）, ｜b｜/（1 ＋｜x｜ log ｜x｜） ∈ L∞（Rd） and ｜ b｜ φ（｜ b｜） ∈ Ll1oc（Rd）, where φ（r） = log log（r ＋ c）, c 0. Then, there exists a unique regular Lagrangian flow associated with the ODE X˙（t, x） = b（X（t, x））, X（0, x） = x.

关键词： DiPerna-Lions flow Hardy-Littlewood maximal function

FLOW PATTERNS AND FORCE CHARACTERISTICS OF LAMINAR FLOW PAST FOUR CYLINDERS IN DIAMOND ARRANGEMENT

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Journal of Hydrodynamics 2011年第1期23卷 55-64页

作者： zou Lin LIN Yu-feng LU Hong School of Mechanical and Electronic Engineering Wuhan University of Technology Wuhan 430070 China department of Mechanical Engineering The Hong Kong Polytechnic University Hong Kong China

A three-dimensional numerical investigation of cross-flow past four circular cylinders in a diamond arrangement at Reynolds number of 200 is carried *** the spacing ratios（L /D）ranging from 1.2 to 5.0,the flow patterns can be classified into three basic *** critical spacing ratio for the transition from narrow gap flow pattern to vortex impingement flow pattern around the cylinders is found to beL /D=3.0,while a single bluff-body flow pattern is observed atL /D=*** relationship between the three-dimensional flow patterns and force characteristics around the four cylinders shows that the variation of forces and Strouhal numbers againstL /D are generally governed by these three kinds of flow *** is concluded that the spacing ratio has important effects on the development of the free shear layers about the cylinders and hence has significant effects on the force and pressure characteristics of the four cylinders with different spacing ratios.

关键词： four cylinders spacing ratio flow pattern force characteristics

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 department of computer science China University of GeoSciences Wuhan Hubei China department of computer science Zhuzhou Institute of Technology Zhuzhou Hunan China State Key Laboratory of Software Engineering Wuhan University Wuhan Hubei China

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