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A Novel Stable Clustering Design Method for Hierarchical Satellite Network

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Chinese Journal of Aeronautics 2010年第1期23卷 91-102页

作者： Zhou Mu,Guo Qing,Wang Zhenyong communication Research Center,School of Electronics and Information engineering,Harbin institute of technology,Harbin 150001,china [a] communication Research Center School of Electronics Information engineering Harbin Institute of Technology Harbin 150001 China

This article proposes a novel stable clustering design method for hierarchical satellite network in order to increase its stability,reduce the overhead of storage and exert effective control of the delay performances based on a 5-dimensional vector model. According to the function of stability measureinent and owing to the limitation of minimal average routing table length, the hierarchical satellite network is grouped into separate stable connected clusters to improve destruction resistance and reconstruction ability in the future integrated network. In each cluster, redundant communication links with little contribution to network stability and slight influences on delay variation are deleted to satisfy the requirements for stability and connectivity by means of optimal link resources, and, also, the idea of logical weight is introduced to select the optimal satellites used to communicate with neighboring cluster satellites. Finally, the feasibility and effectiveness of the proposed method are verified by comparing it with the simulated performances of other two typical hierarchical satellite networks, double layer satellite constellation（DLSC） and satellite over satellite（SOS）.

关键词： satellite network hierarchical structure stability analysis clustering algorithms vector measurements

Theoretical calculation of the finishing rolling elongation in non-quenched and tempered Si-Mn steel

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Progress in Natural Science:Materials International 2006年第1期16卷 78-83页

作者： LIU Zhilin and LIN Cheng (department of Materials and Chemical engineering, Liaoning institute of technology, Jinzhou 121001, china) department of Materials and Chemical engineering Liaoning Institute of Technology Jinzhou 121001 China

The finishing rolling elongation in the non-quenched and tempered Si-Mn steel is theoretically calculated using the cova lent electron number nA of the strongest bond in alloying phases and the interface electron density difference △ρ. Calculations show that the finishing rolling elongation of the non-quenched and tempered Si-Mn steel can be achieved by subtracting all the elongation decrements of solution strengthening, precipitation strengthening, and interface strengthening from the elongation of the refined α-Fe matrix. The calculated results of the finishing rolling tensile strength σb, the finishing rolling yield strength σs, and the finishing elongation δ of Q345 steel and BG420CL steel agree well with the measured values.

关键词： electron structure parameters non-quenched and tempered steel elongation and calculation.

Two Novel Compact High-Isolation Polarization-Independent Four-Port Optical Circulators

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光通信技术 1998年第2期 160-165页

作者： Xu Rongkai Xu Peiying(department of Electronic Science & engineering,nanjing University,nanjing 210093)

Two new designed compact high-isolation polarization-independent opticalcirculator have been conceived. The four-port circulators have been designed for 1. 3μmsingle-mode fiber systems. Their composition are very simple. Theoretical calculationsindicate the second one has the insertion loss and isolation are≤1. 2dB and ≥50dB respectively.

关键词： Optical circulator Isolation Extinction ratio

A SWITCHED CAPACITOR CIRCUIT ANALYSIS PROGRAM AND ITS APPLICATIONS

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Journal of Electronics(china) 1988年第3期5卷 172-180页

作者：陆跃沈永朝 Radio engineering department nanjing institute of technology

A program developed for analyzing arbitrary N-phase switched capacitor circuits is *** of the program is *** program simulation facilities,such as time-domain analysis,frequence-domain analysis,sensitivity analysis and multiple ohjective optimization are *** used in the program is introduced *** examples are given to show the application of theprogram.

关键词： Circuit Theory SC network Computer aided circuit analysis

Reconfigurable design and implementation of the MD6 Hash function

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The Journal of china Universities of Posts and Telecommunications 2010年第2期17卷 109-115页

作者： GAO Xian-wei department of Electronic and Information engineering,Beijing Electronic Science and technology institute,Beijing 100070,china [a] department of Electronic Information engineering Beijing Electronic Science technology institute Beijing 100070 China

Efficient reconfigurable field programmable gate array （FPGA） architectures for the MD6-224/256/384/512 Hash algorithm are proposed in this article. The basic iterative compact design requires 923 ALMs and achieves a throughput ranging from 225 Mbit/s to 394 Mbit/s at a maximum frequency of 198 MHz. The 32-step-urtrolled high-throughput design requires 7 090 ALMs and achieves a throughput ranges from 5 776 Mbit/s to 9 490 Mbit/s at a maximum frequency of 173 MHz. The simulation results show that high flexibility and efficient FPGA implementation of the MD6 Hash function is achieved.

关键词： SHA-3 MD6 reconfigurable iterative loop-unrolling

Generalized Self-Adaptive Genetic Algorithms

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 72-75页

作者： Bin Wu Xuyan Tu Jian Wu Information engineering School, University of Science and technology Beijing, Beijing 100083, china department of Information and Control engineering, Southwest institute of technology, Mianyang 621002, china Information engineering School University of Science and Technology Beijing Beijing 100083 China department of Information and Control engineering Southwest Institute of Technology Mianyang 621002 China

In order to solve the problem between searching performance and convergence of genetic algorithms, a fast genetic algorithm generalized self-adaptive genetic algorithm (GSAGA) is presented. (1) Evenly distributed initial population is generated. (2) Superior individuals are not broken because of crossover and mutation operation for they are sent to subgeneration directly. (3) High quality im- migrants are introduced according to the condition of the population schema. (4) Crossover and mutation are operated on self-adaptation. Therefore, GSAGA solves the coordination problem between convergence and searching performance. In GSAGA, the searching per- formance and global convergence are greatly improved compared with many existing genetic algorithms. Through simulation, the val- idity of this modified genetic algorithm is proved.

关键词： generalized self-adaptive genetic algorithm initial population immigration fitness function

THE STABILITY OF THE θ-METHODS FOR DELAYDIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 1999年第4期17卷 441-448页

作者： Jing-jun Zhao Ming-zhu Liu(department of mathematics, Harbin institute of technology, Harbin 150001, china)Shen-shan Qiu(department of Computer Science and engineering, Harbin institute of technology, Harbin 150001, china) 哈尔滨工业大学数学系黑龙江哈尔滨 150001 哈尔滨工业大学数学系黑龙江哈尔滨哈尔滨工业大学计算机系黑龙江哈尔滨

This paper deals with the stability analysis of numerical methods for the solution of delay differential equations. We focus on the behaviour of three θ-methodsin the solution of the linear test equation u'(t)-A(t)u(t)+B(t)u( (t)) with (t)and A(t),B(t) continuous matrix functions. The stability regions for the threeθ-methods are determined.

关键词： Delay differential equations Numerical solution Stabilityl θ-methods.

Electroabsorption spectrum of substituted polyphenylacetylenes

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Chinese Science Bulletin 1998年第14期43卷 1215-1219页

作者： CHENG Xiaoman department of Optoelectronic Information engineering, Tianjin institute of technology, Tianjin 300191, china department of Optoelectronic Information engineering Tianjin Institute of Technology Tianjin China

Electroabsorption (EA) measurements on thin films of poly[ o (trimethylsilyl) phenylacetylene] and poly[ o (trimethylsilylmethyl) phenylacetylene] have been performed. The spectral change induced by an exernal electric field (EA spectra) has been observed, which shows the similar shape of the second derivative of the optical absorption spectra. The change in the absorption Δ α is obtained from the EA spectrum, and Δ n is calculated through Kramers_Krong transformation. The optical properties of substituted polyphenylacetylenes (PPAs) were discussed.

关键词： substituted polyphenylacetylenes electroabsorption spectrum optical nonlinearities

A Sensitivity-Based Heuristic Search for Constrained Optimization in Complex Systems

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Journal of Systems engineering and Electronics 1999年第1期10卷 75-80页

作者： Gao Peiwang Ma Xiaoqing (department of Mechanical and Electronic engineering, Beijing institute of technology, 100081, P. R. china)(Received September 4, 1998) department of Mechanical and Electronic engineering Beijing Institute of Technology 100081 P. R. China

On the basis of sensitivity analysis, an algorithm presented in this paper does a multi dimensional heuristic search for the optimal solution of complex systems in the feasible intervals of components reliability. Compared with some existing methods, the algorithm both has heuristic speciality that it is modest and easy to implement, and obtains the optimal solution as exact methods do.

关键词： Complex systems Systems reliability Sensitivity Heuristic methods.