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Practical Issues Concerning Moment Invariants

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Journal of Systems engineering and electronics 1996年第1期7卷 43-57页

作者： Xiaojian Xu & A.G. Constantinides (Beijing Institute of Environment Features)(Depatment of electrical and electronic engineering Imperial College of Science,Technology and Medicine) Beijing Institute of Environment Features department of electrical and electronic {3. Imperial College of Science Technology and Medicine

In this report several practical issues about moment invariants with application to image classification are concerned. A modified formulation for the approximation of the moments of digital images is suggested. Four ... 详细信息

关键词： Pattern recognition Image processing,Momeent invariant,Fuzzy logic.

Robust integral sliding mode control for uncertain systems with multiple time delays

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控制理论与应用（英文版） 2010年第2期8卷 211-214页

作者： Xiaoyu ZHANG, Xiangna LI (department of electronic and Information engineering, North China Institute of Science and Technology, Beijing 101601, China) department of electronic and Information engineering North China Institute of Science and Technology Beijing China

This paper proposes a robust integral sliding mode (RISM) manifold and the corresponding stabilization control law for uncertain systems with multiple time-varying time delays based on the techniques of linear matrix inequalities (LMI). The sufficient condition for the existence of the RISM manifold is given in terms of LMI, and then, the sliding mode control (SMC) law that can keep the system state on the RISM manifold from the initial time moment is developed. The efficiency and feasibility of the results are illustrated by a numerical example.

关键词： Robust control Integral sliding mode Time-delay systems LMI

INFORMATION AND COMPLEXITY IN CONTROL SYSTEMS: A TUTORIAL

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Journal of Systems Science & Complexity 2001年第1期14卷 1-16页

作者： WANG Leyi (department of electrical and Computer engineering, Wayne State University, Detroit, Michigan 48202, USA) Wayne State University 美国 48202

This is a tutorial paper which presents schematically the concepts of information, uncertainty, and complexity, and their relationships in their applications to control systems. By focusing on exact or lower bounds on achievable performance in the presence of uncertainties, studies of complexity in a control system can potentially reveal fundamentally limiting factors of the system, suggest beneficial modifications to system structures and hardware configurations to remove these limitations, provide benchmark values for evaluating a design and for quantifying rooms for performance improvement, and demonstrate intrinsic tradeoffs. Compared to its counterparts in communications (Shannon’s information theory), computations (computational complexity and information-based complexity), and approxima- tions (n-widths and Kolmogorov entropy), studies of information and complexity in control systems encounter further challenges, such as characterization of feedback robustness, interaction between identification and control, and co-existence of deterministic and stochastic uncertainties. Some of these issues are outlined and discussed.

关键词： Information uncertainty complexity control identification.

A Modified T-test Feature Selection Method and Its Application on the HapMap Genotype Data

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Genomics,Proteomics & Bioinformatics 2007年第Z1期 242-249页

作者： Nina Zhou and Lipo Wang School of electrical and electronic engineering,Nanyang Technological University,Singapore.

Single nucleotide polymorphisms (SNPs) are genetic variations that determine the differences between any two unrelated individuals. Various population groups can be distinguished from each other using SNPs. For instance,the HapMap dataset has four population groups with about ten million SNPs. For more insights on human evolution,ethnic variation,and population assignment,we propose to find out which SNPs are significant in determining the population groups and then to classify different populations using these relevant SNPs as input features. In this study,we developed a modified t-test ranking measure and applied it to the HapMap genotype data. Firstly,we rank all SNPs in comparison with other feature importance measures including F-statistics and the informativeness for assignment. Secondly,we select different numbers of the most highly ranked SNPs as the input to a classifier,such as the support vector machine,so as to find the best feature subset corresponding to the best classification accuracy. Experimental results showed that the proposed method is very effective in finding SNPs that are significant in determining the population groups,with reduced computational burden and better classification accuracy.

关键词： SNP modified t-test F-statistics SVM

Arithmetic computation using self-assembly of DNA tiles:subtraction and division

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Progress in Natural Science:Materials International 2009年第3期19卷 377-388页

作者： Xuncai Zhang a,b, Yanfeng Wang b, Zhihua Chen a, Jin Xu a,*, Guangzhao Cui b a The Key Laboratory of Image Processing and Intelligent Control, department of Control Science and engineering, Huazhong University of Science and Technology, Wuhan 43.074, China b School of electrical and {3. engineering, Zhengzhou University of Light Industry, Zhengzhou 450002, China The Key Laboratory of Image Processing and Intelligent Control Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China School of electrical and electronic engineering Zhengzhou University of Light Industry Zhengzhou 450002 China

Recently, experiments have demonstrated that simple binary arithmetic and logical operations can be computed by the process of self- assembly of DNA tiles. In this paper, we show how the tile assembly process can be used for subtraction and division. In order to achieve this aim, four systems, including the comparator system, the duplicator system, the subtraction system, and the division system, are pro- posed to compute the difference and quotient of two input numbers using the tile assembly model. This work indicates that these systems can be carried out in polynomial time with optimal O(1) distinct tile types in parallel and at very low cost. Furthermore, we provide a scheme to factor the product of two prime numbers, and it is a breakthrough in basic biological operations using a molecular computer by self-assembly.

关键词： Self-assembly Subtractor Divider Tile assembly model DNA tiles DNA computing

Preparation of nanocrystalline BaTiO_3.ceramics

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Science China(Technological Sciences) 2009年第6期52卷 1730-1734页

作者： DENG XiangYun1,2,LI DeJun1,LI JianBao2,WANG XiaoHui3.& LI LongTu3.1 College of Physics and electronic Information,Tianjin Normal University,Tianjin 3.03.7,China 2 Materials and Chemical engineering Institute,Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical engineering Material of Ministry of Education,Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti,Hainan University,Haikou 570228,China {3. of Materials Science and engineering,Tsinghua University,Beijing 100084,China College of Physics and electronic Information Tianjin Normal University Tianjin China Materials and Chemical engineering Institute Key Laboratory for Hainan Advantage Resources and Applied Technology in Chemical Engineering Material of Ministry of Education Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Hainan University Haikou China department of Materials Science and engineering Tsinghua University Beijing China

The high-dense nanocrystalline BaTiO3.BT)ceramics with grain size smaller than 100nm have been successfully prepared by the two step sintering and the spark plasma sintering(SPS)*** successive transitions in nanograin BT ceramics from rhombohedral to orthorhombic,tetragonal and cubic transitions,similar to those in coarse BT ceramics,were revealed by in-situ temperature dependent Raman *** multiphase coexistence and the diffused phase transition character were demonstrated in the 8nm nanocrystalline BT ceramics.

关键词： nanocrystalline BaTiO3 ceramics preparation microstructure size effect

Experimental measurement of growth patterns on fossil corals:Secular variation in ancient Earth-Sun distances

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Chinese Science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3.4,LI ZhengBin2,3.& LEI Yang1 1 department of Physics,Peking University,Beijing 100871,China 2 department of electrical {3. and Computer Science,Peking University,Beijing 100871,China 3.State Key Laboratory of Advanced Optical Communication Systems & Networks,Peking University,Beijing 100871,China 4 Committee of Yuanpei Honors Program,Peking University,Beijing 100871,China department of Physics Peking University Beijing China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing China Committee of Yuanpei Honors Program Peking University Beijing China department of electrical engineering and Computer Science Peking University Beijing China

In recent years,much attention has been given to the increase in the Earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient Earth-Sun *** mechanical analysis of both the Earth-Sun and Earth-Moon systems,these patterns confirmed an increase in the Earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the Earth has been leaving the Sun over the past 0.53.billion *** Earth's semi-major axis was 146 million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14 m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the Earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化

Application of asymptotic waveform approximation technique to hybrid FE/BI method for 3. scattering

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Science in China(Series F) 2007年第1期50卷 124-134页

作者： PENG Zhen1,2,3.& SHENG XinQing2 1 Institute of electronics, Chinese Academy of Sciences, Beijing 100080, China 2 department of electronic {3., Beijing Institute of Technology, Beijing 100081, China 3.Graduated University of Chinese Academy of Sciences, Beijing 10003., China Institute of electronics Chinese Academy of Sciences Beijing China department of electronic engineering Beijing Institute of Technology Beijing China Graduated University of Chinese Academy of Sciences Beijing China

The asymptotic waveform evaluation （AWE） technique is a rational function approximation method in computational mathemetics, which is used in many appllcations in computational electromagnetlca. In this paper, the performance of the AWE technique in conjunction with hybrid finite element/boundary integral （FE/BI） method is firstly Inveetlgeted. The formuletlon of the AWE applied in hybrid FE/BI method is given in detail. The characteristic implementation of the application of the AWE to the hybrid FE/BI method is discussed. Numarlcel results demonstrate that the AWE technique can greatly speed up the hybrid FE/BI method to acquire wide-band and wide-angle backecatter radar-cross-section （RCS） by complex targets.

关键词： hybrid FE/BI AWE electromagnetic scattering RCS

Software Simulation in GSM Environment and Hardware Implementation of Improved Multi-band Excitation Vocoder

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通信学报 1998年第5期 19-28页

作者： Kuang Jingming Li Feng Liu Botao (electronic engineering department, Beijing Institute of Technology, Beijing 100081)

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ＳｏｆｔｗａｒｅＳｉｍｕｌａｔｉｏｎｉｎＧＳＭＥｎｖｉｒｏｎｍｅｎｔａｎｄＨａｒｄｗａｒｅＩｍｐｌｅｍｅｎｔａｔｉｏｎｏｆＩｍｐｒｏｖｅｄＭｕｌｔｉｂａｎｄＥｘｃｉｔａｔｉｏｎＶｏｃｏｄｅｒＫｕａｎｇＪｉｎｇｍｉｎｇＬｉＦｅｎｇＬｉｕＢｏｔａｏ（Ｅ...

关键词： vocoder IMBE improved multi band excitation GSM software simulation