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Science China(information Sciences) 2010年第1期53卷 50-63页

作者： LIU XuanZhe1,2, HUANG Gang1,2 & MEI Hong1,2 1school of electronics Engineering and Computer Science, Peking University, Beijing 100871, China 2Key Laboratory of High Confidence Software Technologies, Ministry of Education, Peking University, Beijing 100871, China 1. school of electronics Engineering and Computer Science Peking University Beijing 100871 China2. Key Laboratory of High Confidence Software Technologies Ministry of Education Peking University Beijing 100871 China

In the recent years, the web has kept growing rapidly and undergone tremendous changes towards a user-centric environment. With the proliferation of services available on the Internet, millions of users are able to voluntarily participate in and collaborate for their own interests and benefits by means of service composition. However, due to the ever increasing number of services, it then becomes a challenging issue to enable the users to rapidly select and compose the proper services. In this paper, we propose an approach which utilizes service communities for automated service composition. This paper makes three contributions. Firstly, we propose the service community architecture and identify two key components to facilitate service discovery and composition. Secondly, assisted by the service community, we provide two composition types to help users explore the space of potential composition opportunities without having to understand too many details of individual candidate services. Finally, we evaluate our approach by performance analysis and provide a web-based prototype that lowers the entry barrier for the users.

关键词： services computing service composition service community

Adaptive Coordination of Multi-agent Systems with Unknown Parameters

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Adaptive Coordination of Multi-agent Systems with Unknown Pa...

Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 5. Years

2010 Chinese Control and Decision Conference

作者： Jianzhong Gu~1,Hongyong Yang~2 1.school of Mathematics and information,Ludong University,Yantai 264025.China 2.school of information Science and Engineering,Ludong University,Yantai 264025.China

＜正＞In this paper,we study a leader-following consensus problem of a group of autonomous agents with unknown *** the topology graph has symmetric weights,linear controllers and adaptive laws are proposed to guarantee that the states of all agents track the leader’s state,and the errors of parameters eventually converge to the compact set which can be made as small as desired by an appropriate choice of the design parameters.

关键词： Leader-following Multi-agent systems Consensus Adaptive law

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2,3 , ZHOU Wancun 1 ,ZHOU Jieming 4 , ZHU Mingcang 3,5.1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences , Chengdu 610041, Sichuan, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100049, China 3. Sichuan Institute of Land Resource Management, Chengdu 610041, Sichuan , China 4. Department of Resources and Environment Science, Sichuan Normal University , Chengdu 610061, Sichuan, China 5. College of information Engineering, Chengdu University of Technology, Chengdu 61005., Sichuan, China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of Chinese Academy of Sciences Beijing China Sichuan Institute of Land Resource Management Chengdu Sichuan China Department of Resources and Environment Science Sichuan Normal University Chengdu Sichuan China College of information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995.the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 5. years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

Poincaré and Poincaré-Cartan integral invariants of a generalized Hamiltonian system

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Communications in Nonlinear Science and Numerical Simulation 2001年第1期6卷 45-49页

作者： Yongxin GUO, Liyan JIANG and Ying YU (Department of Physics, Liaoning University, Shenyang 110026, China Department of electronics and information Engineering, Dandong Advanced Academy, Dandong 118000, China school of Science, Shenyang University of Te Department of Physics Liaoning University Shenyang 110036 China Dept. of electronics and Info. Eng. Dandong Advanced Academy Dandong 118000 China school of Science Shenyang University of Technology Shenyang 110023 China

Without Darboux’s transformation, the traditional Hamiltonian formulation of dynamical systems is only suitable to conservative systems or self-adjoint systems. Based on an extension of dynamic space of Birkhoffian systems to a generalized phase space by intro- ducing dummy variables, a generalized Hamiltonian canonical formulation of general systems is constructed, which admits symplectic structure. There exist integral invariants of Poincare and Poincare-Cartan’s type for such systems.

关键词： Birkhoffian systems symplectic structure integral invariants

小波变换的信号分形分析及其在心电信号处理中的应用研究

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物理学报 2002年第4期51卷 759-762页

作者：邓勇施文康刘琪上海交通大学电子信息学院上海200030 上海交通大学生命科学学院上海200030

介绍了一种基于小波变换的分形分析方法 ,并将它成功地应用于心房纤颤的检测中 .该方法提取了一个特征值r,结果表明在心房纤颤开始时 ,特征值是上升的 ,心房纤颤结束后 ,特征值又慢慢恢复到原来的数值 ,由此可以成功地检测出心房纤颤的... 详细信息

介绍了一种基于小波变换的分形分析方法 ,并将它成功地应用于心房纤颤的检测中 .该方法提取了一个特征值r,结果表明在心房纤颤开始时 ,特征值是上升的 ,心房纤颤结束后 ,特征值又慢慢恢复到原来的数值 ,由此可以成功地检测出心房纤颤的开始和结束 .此外 ,由于特征值同时反映了heartratevariability(HRV)信号的复杂程度 ,所以同时它也表明 :心房纤颤开始后。

关键词： HRV 小波变换分形信号分析心电信号处理心血管疾病

Robust Stability of Uncertain Singularly Perturbed Systems with Time-varying Delay

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Robust Stability of Uncertain Singularly Perturbed Systems w...

2010 Chinese Control and Decision Conference

作者： Hong-Chen Sun~1,Xian-Jie Wang~2 1.school of Mathematics and information Science,Yantai University,Yantai 264005.2.school of Mathematics and information Science,Yantai University,Yantai 264005

＜正＞The problem of robust stability for a class of uncertain singularly perturbed systems with time-varying delay is presented.A new delay dependent stability criteria is devised by a method converting the singularly perturbed systems into a descriptor system *** a Lyapunov-Krasovskii function is *** delay dependent stability sufficient condition for the descriptor system is obtained with Unear matrix inequaUty method.A numerical example is given to illustrate the efficacy of the proposed approach.

关键词： LMI Optimization Varying Time-delay Singularly Perturbed Systems Descriptor Systems

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船筏减振双线性系统的最优半主动阻尼控制

振动与冲击 2012年第20期31卷 131-136页

作者：高新科上海交通大学电子信息与电气工程学院上海200240 洛阳师范学院信息技术学院洛阳471022

以船筏减振双线性系统为分析对象,利用极大值原理,通过受约束的梯度法数值求得船筏减振双线性系统的最优半主动阻尼控制曲线。由于控制曲线的非线性特性很强,甚至存在不可导的问题,引入脉冲函数并进行理论推导,解决了不可导曲线无法求... 详细信息

以船筏减振双线性系统为分析对象,利用极大值原理,通过受约束的梯度法数值求得船筏减振双线性系统的最优半主动阻尼控制曲线。由于控制曲线的非线性特性很强,甚至存在不可导的问题,引入脉冲函数并进行理论推导,解决了不可导曲线无法求解的缺陷,从而适用于双线性建模的系统。最后比较新方法与被动阻尼系统,半主动天棚阻尼系统在随机和冲击信号激励下的减振效果。结果显示:船筏双线性系统最优半主动阻尼控制策略是本文所述五种控制策略中减振效果最好的,并且对冲击信号的减振效果明显好于对随机信号减振。

关键词：阻尼减振半主动控制双线性系统

Spotlight SAR sparse sampling and imaging method based on compressive sensing

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Science China(information Sciences) 2012年第8期55卷 1816-1829页

作者： XU HuaPing1,YOU YaNan1,LI ChunSheng1&ZHANG LvQian2 1S chool of electronics and information Engineering,Beihang University,Beijing 100191,China 2C hinese Academy of Engineering,Beijing 100088,China 1. school of electronics and information Engineering Beihang University Beijing 100191 China2. Chinese Academy of Engineering Beijing 100088 China

Spotlight synthetic aperture radar(SAR)emits a chirp signal and the echo bandwidth can be reduced through dechirp processing,where the A/D sampling rate decreases accordingly at the *** sensing allows the compressible signal to be reconstructed with a high probability using only a few samples by solving a linear program *** paper presents a novel signal sampling and imaging method for application to spotlight SAR based on compressive *** signal is randomly sampled after dechirp processing to form a low-dimensional sample set,and the dechirp basis is imported to reconstruct the dechirp *** pursuit(MP)is used as a reconstruction *** reconstructed signal uses polar format algorithm(PFA)for *** our novel mechanism increases the system complexity to an extent,the data storage requirements can be compressed *** simulations verify the feasibility and accuracy of spotlight SAR signal processing via compressive sensing,and the method still obtains acceptable imaging results with 10%of the original echo data.

关键词： spotlight SAR dechirp processing compressive sensing radar signal processing

Power functions with low uniformity on odd characteristic finite fields

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Science China Mathematics 2010年第8期53卷 1931-1940页

作者： ZHA ZhengBang 1,3 & WANG XueLi 2 1 school of Mathematical Sciences,Luoyang Normal University,Luoyang 471022,China 2.school of Mathematical Sciences,South China Normal University,Guangzhou 5.0631,China 3 State Key Laboratory of information Security,Graduate University of Chinese Academy of Sciences,Beijing 100049,China 1. school of Mathematical Sciences Luoyang Normal University Luoyang 471022 China3. State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China2. School of Mathematical Sciences South China Normal University Guangzhou 510631 China

In this paper,we give some new low differential uniformity of some power functions defined on finite fields with odd *** corollaries of the uniformity,we obtain two families of almost perfect nonlinear functions in GF... 详细信息

关键词： almost perfect nonlinear function differential uniform function finite field