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Progress in Natural science:Materials International 2008年第8期18卷 1015-1021页

作者： Lin Lia,*, Yingmin Jiaa, Junping Dub, Shiying Yuan c a The Seventh Research Division, beijing university, beijing 100083, china b beijing key laboratory of intelligent Telecommunications Software and Multimedia, beijing university of Posts and Telecommunications, beijing 100876, china c School of Electrical Engineering and Automation, Henan Polytechnic university, Jiaozuo 454000, china The Seventh Research Division Beijing University Beijing 100083 China beijing key laboratory of intelligent Telecommunications Software and Multimedia Beijing University of Posts and Telecommunications Beijing 100876 China School of Electrical Engineering and Automation Henan Polytechnic University Jiaozuo 454000 China

We study the problem of L2-L1 control for a class of uncertain singular systems with time-delay and norm-bounded parameter uncertainties in this paper. A new delay-dependent robust stability criterion is obtained in terms of linear matrix inequalities (LMIs). Based on this criterion, a state feedback controller is designed to guarantee that the closed-loop system is regular, impulse free and stable with a prescribed L2-L1 performance satisfied for all admissible parameter uncertainties. A simulation example is included to illustrate the effectiveness of the proposed method.

关键词： L2–L1 control Singular systems Delay-dependent condition LMIs

An On-line Monitoring system for Hydrogen Distribution in the Metallic Wall Caused by Hydrogen Permeation

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Journal of Materials science & technology 2001年第3期17卷 346-350页

作者： Gang YU Shenyang university of technology, 110023, china Xueyuan ZHANG and Yuanlong DU state key laboratory for Corrosion and Protection, Institute of Metal Research, Chinese Academy of sciences, Shenyang 110016, china E-mail: yugang@*** Shenyang Univ. of Technol. Shenyang 110023 China

Based on the electrochemical permeation technique and the patent by Du, an intelligent elec-trochemical measurement system for determination of the hydrogen distribution in the wall of hydrogenation reactor has been developed and tested. It consists of a PC computer, a single chip unit, an I/V converter and an electrochemical hydrogen probe. The construction of the electrochemical hydrogen probe is described and the features of the measured system are given. The diffusion coefficient of 2.25CrlMo steel determined with present system was in good agree-ment with the value in the literature. Experimental results of hydrogen concentration in a wall of hydrogen charged testing autoclave made of AISI 321 stainless steel are presented. The present system can intelligently display hydrogen amount-of-substance concentration and mass fraction concentration, hydrogen concentration distribution curves in steels, permeation current density curve. An intelligent detection technique can be provided for predicting the susceptibility to hydrogen-induced cracks owing to hydrogen permeation in the wall of hydrogenation reactor in the field.

关键词： Hydrogen bonds

FUTURE OF APPLIED STEREOLOGY IN MATERIALS science AND ENGINEERING

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FUTURE OF APPLIED STEREOLOGY IN MATERIALS SCIENCE AND ENGINE...

第十三届国际体视学大会

作者： Guoquan Liu~(1 2) 1.School of Materials science and Engineering university of science and technology beijing beijing 100083 china 2.state key laboratory for Advanced Metals and Materials university of science and technology beijing beijing 100083 china

＜正＞It has been well demonstrated that materials science cannot evolve into a truly quantitative science without stereology（Robert *** Coming of Materials ***:Elsevier,2001;Liu,*** of Microscopy（Oxford）.1993,171（1） 57-68）.In this paper,the roles of stereology,and the future of the stereology in materials science and engineering will be reviewed and *** emphasis will be placed on what stereology can do and can not do as well as related precautions,and how stereology combines with newly developed 3D reconstruction,Thermocalc calculation,computer simulation,and so on,in order to serve the materials science and engineering better.

关键词： applied stereology materials science quantitative microscopy image analysis

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一种基于部件的人像组合算法

计算机工程与应用 2002年第12期38卷 54-56,174页

作者：刘通苏光大清华大学电子工程系智能技术与系统国家重点实验室北京100084

人像组合技术是在公安系统中广泛采用的刑侦破案手段。在实际应用中,该项技术协助公安干警侦破了许多重大刑事案件。文章根据图象处理和视觉理论基础,提出了一种新的人像组合算法,解决了组像实现方面的难题。

关键词：部件人像组合算法边界平滑图像处理计算机

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Petri网共享T型子网合成活性分析

系统仿真学报 2007年第A1期19卷 4-8,37页

作者：夏传良中国科学院软件所计算机科学国家重点实验室北京工业大学计算机科学与技术学院北京100022

为解决子系统共享问题,提出了经由Petri网系统共享T-型子网构成共享子网合成网的解决方案。共享T-型子网合成是研究复杂Petri网系统性质的一个有效途径。研究了共享T-型子网合成对参与合成的各网系统的活性的继承关系,给出了合成网保持... 详细信息

为解决子系统共享问题,提出了经由Petri网系统共享T-型子网构成共享子网合成网的解决方案。共享T-型子网合成是研究复杂Petri网系统性质的一个有效途径。研究了共享T-型子网合成对参与合成的各网系统的活性的继承关系,给出了合成网保持活性的充分条件或充要条件。随后给出的有关制造系统设计和分析的实例,说明了该合成方法的有效性。本文的结果可为Petri网系统合成的静态和动态性质的考察提供有效途径,对系统的设计和验证具有重要的指导意义。

关键词： Petri网合成活性有界性系统设计

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可继续学习的构造型神经网络构造算法

计算机工程与应用 2002年第8期38卷 10-12,169页

作者：陶品张钹叶榛清华大学计算机系智能技术与系统国家重点实验室北京100084

构造型神经网络模型通过将样本映射到单位超球面上并用覆盖方法进行识别,具有计算速度快、识别率高、几何意义明显等优点。但是常用的基于交叉覆盖的方法在首次构造完成后,难以再继续进行修改和加强,从而阻碍了网络的再学习能力。文章... 详细信息

构造型神经网络模型通过将样本映射到单位超球面上并用覆盖方法进行识别,具有计算速度快、识别率高、几何意义明显等优点。但是常用的基于交叉覆盖的方法在首次构造完成后,难以再继续进行修改和加强,从而阻碍了网络的再学习能力。文章提出了该构造型神经网络的一种双交叉覆盖方法,一方面吸收了原交叉覆盖的优点,一方面提供了良好的再学习能力。通过实验验证,该方法可以较好地运用到构造型神经网络的增量学习中。

关键词：构造型神经网络构造算法可继续学习增量学习

SAR image despeckling based on edge detection and nonsubsampled second generation bandelets

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Journal of systems Engineering and Electronics 2009年第3期20卷 519-526页

作者： Zhang Wenge~(1,2),Liu Fang~(1,2),Jiao Licheng~(2,3)& Gao Xinbo~(2,3) 1.School of computer science and technology,Xidian Univ.,Xi’an 710071,P.R.china 2.key Lab.of intelligent Perception and Image Understanding of Ministry of Education of china,Xi’an 710071,P.R.china 3.Inst,of intelligent Information Processing,Xidian Univ.,Xi’an 710071,P.R.china School of computer science and technology Xidian Univ. Xi'an 710071 P. R. China key Lab. of intelligent Perception and Image Understanding of Ministry of Education of china Xi'an 710071 P. R. China key Lab. of intelligent Perception and Image Understanding of Ministry of Education of china Xi'an 710071 P. R. China Inst. of intelligent Information Processing Xidian Univ. Xi'an 710071 P. R. China

To preserve the sharp features and details of the synthetic aperture radar （SAR） image effectively when despeckling, a despeckling algorithm with edge detection in nonsubsampled second generation bandelet transform （NSBT） domain is proposed. First, the Canny operator is utilized to detect and remove edges from the SAR image. Then the NSBT which has an optimal approximation to the edges of images and a hard thresholding rule are used to approximate the details while despeckling the edge-removed image. Finally, the removed edges are added to the reconstructed image. As the edges axe detected and protected, and the NSBT is used, the proposed algorithm reaches the state-of-the-art effect which realizes both despeckling and preserving edges and details simultaneously. Experimental results show that both the subjective visual effect and the mainly objective performance indexes of the proposed algorithm outperform that of both Bayesian wavelet shrinkage with edge detection and Bayesian least square-Gaussian scale mixture （BLS-GSM）.

关键词： computer image processing synthetic aperture radar speckle edge detection nonsubsampled second generation bandelet transform Canny operator threshold shrinkage.

The Research and Development of Worm Defense Strategies

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The Research and Development of Worm Defense Strategies

2010 3rd IEEE International Conference on computer science and Information technology—ICCSIT 2010

作者： Liuqi 1 1 state key laboratory of Information Security Graduate university of Chinese Academy of science beijing china Ma Guoqing 2 2 National key laboratory of science and technology on Information system Security beijing china

The deterioration of worm propagation on internet in recent years has pushed the research in the field of worm defense, as a result there are coming up plenty of worm defense strategies. This paper refers to make the systematic study of the complete worm defense strategies and provide taxonomy of worm defense system strategies according to the key factors of each defense category. As guideline for the design of worm defense, we compare the present evaluation of the worm defense strategies, and give a highlight on the trendy of worm defense in the future at the end.

关键词： worm defense evaluation math modeling simulation

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基于群体智能的网络信息自组织方式

计算机科学 2003年第6期30卷 84-87,125页

作者：刘燕帅典勋柴震川华东理工大学计算机科学系上海200237 清华大学智能技术与系统国家重点实验室北京100084

We design and implement a novel information self-organization model based on Generalized Cellular Automata (GCA), to accomplish network information content self-organization employing the idea of swarm intelligence. Through constructing correspondent cell rules and the mapping of complex network environment to our GCA, reasonable distribution of network information from different information sources can be achieved on different notes according to dynamic variation of local network circumstances. Simulation experiment results show many advantages of our methodology over present approaches in terms of efficiency, adaptability, reliability, and easy hardware imple- mentation.

关键词：计算机网络群体智能网络信息自组织方式广义细胞自动机信息资源