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Repetitive learning control of nonlinear systems over finite intervals

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Science china({1. Sciences) 2010年第1期53卷 115-128页

作者： SUN MingXuan1. WANG DanWei2 & CHEN PengNian3 1.ollege of information {1., Zhejiang university of Technology, Hangzhou 31.01., china 2School of Electrical and Electronic {1., Nanyang Technological university, Singapore 639794 3department of Mathematics, china Institute of Metrology, Hangzhou 31.01., china 1. College of information {1. Zhejiang University of Technology Hangzhou 310014 China2. School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639794 Singapore3. Department of Mathematics China Institute of Metrology Hangzhou 310018 China

Iterative learning control requires initial repositioning, while the time functions to be learned should be of periodicity in repetitive control. However, there are cases in practice where the time-varying unknowns are not periodic but repetitive, and repetitive learning control is applicable with avoidance of initial repositioning. In this paper, repetitive learning control designs are presented for a broader class of nonlinear systems over finite intervals. The Freeman formula is modified and used for stabilization of the nominal nonlinear time-varying system undertaken. The global stability of the learning system and asymptotic convergence of the tracking error are established through analysis of both partially and fully saturated learning algorithms, respectively. The repetitive learning control method is theoretically shown to be effective in dealing with time-varying parametric uncertainties.

关键词： Initial condition problem convergence iterative learning control repetitive control repetitive learning control nonlinear systems

A general communication performance evaluation model based on routing path decomposition

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Journal of Zhejiang university-Science C(Computers and Electronics) 2011年第7期12卷 561-573页

作者： Ai-lian CHENG 1.Yun PAN 1.2,Xiao-lang YAN 2,Ruo-hong HUAN 3 (1.department of {1. Science and Electronic engineering,Zhejiang university,Hangzhou 31.027,china) (2 Institute of VLSI Design,Zhejiang university,Hangzhou 31.027,china) (3 College of Computer Science and Technology,Zhejiang university of Technology,Hangzhou 31.023,china) department of {1. Science and Electronic engineering Zhejiang University Institute of VLSI Design Zhejiang University

The network-on-chip (NoC) architecture is a main factor affecting the system performance of complicated multi-processor systems-on-chips (MPSoCs).To evaluate the effects of the NoC architectures on communication efficiency,several kinds of techniques have been developed,including various simulators and analytical *** simulators are accurate but time consuming,especially in large space explorations of diverse network configurations;in contrast,the analytical models are fast and flexible,providing alternative methods for performance *** this paper,we propose a general analytical model to esti-mate the communication performance for arbitrary NoCs with wormhole routing and virtual channel flow *** resolve the inherent dependency of successive links occupied by one packet in wormhole routing,we propose the routing path decomposition approach to generating a series of ordered link *** we use the traditional queuing system to derive the fine-grained transmission latency for each network *** to our experiments,the proposed analytical model provides a good approximation of the average packet latency to the simulation results,and estimates the network throughput precisely under various NoC configurations and ***,the analytical model runs about 1. 5 times faster than the cycle-accurate NoC *** applications of the model including bottleneck detection and virtual channel allocation are also presented.

关键词： Analytical model Communication performance Network-on-chip (NoC) Queuing system Routing path decom-position Virtual channel

A kernel learning framework for domain adaptation learning

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Science china({1. Sciences) 2012年第9期55卷 1983-2007页

作者： TAO JianWen 1.3,CHUNG FuLai 2 & WANG ShiTong 1.2 1.School of Digital Media,Jiangnan university,Wuxi 21.1.2,{1. 2 department of Computing,Hong Kong Polytechnic university,Hong Kong,{1. 3 School of information engineering,Zhejiang Business Technology Institute,Ningbo 31.01.,{1. 1. School of Digital Media Jiangnan University Wuxi 214122 China3. School of Information Engineering Zhejiang Business Technology Institute Ningbo 315012 China2. Department of Computing Hong Kong Polytechnic University Hong Kong China

Domain adaptation learning(DAL) methods have shown promising results by utilizing labeled samples from the source(or auxiliary) domain(s) to learn a robust classifier for the target domain which has a few or even no labeled ***,there exist several key issues which need to be addressed in the state-of-theart DAL methods such as sufficient and effective distribution discrepancy metric learning,effective kernel space learning,and multiple source domains transfer learning,*** at the mentioned-above issues,in this paper,we propose a unified kernel learning framework for domain adaptation learning and its effective extension based on multiple kernel learning(MKL) schema,regularized by the proposed new minimum distribution distance metric criterion which minimizes both the distribution mean discrepancy and the distribution scatter discrepancy between source and target domains,into which many existing kernel methods(like support vector machine(SVM),v-SVM,and least-square SVM) can be readily *** framework,referred to as kernel learning for domain adaptation learning(KLDAL),simultaneously learns an optimal kernel space and a robust classifier by minimizing both the structural risk functional and the distribution discrepancy between different ***,we extend the framework KLDAL to multiple kernel learning framework referred to as *** the KLDAL or MKLDAL framework,we also propose three effective formulations called KLDAL-SVM or MKLDAL-SVM with respect to SVM and its variant μ-KLDALSVM or μ-MKLDALSVM with respect to v-SVM,and KLDAL-LSSVM or MKLDAL-LSSVM with respect to the least-square SVM,*** experiments on real-world data sets verify the outperformed or comparable effectiveness of the proposed frameworks.

关键词： domain adaptation learning support vector machine multiple kernel learning maximum mean discrepancy maximum scatter discrepancy

Imaging theory of nonlinear second harmonic and third harmonic generations in confocal microscopy

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Science china(Physics,Mechanics & Astronomy) 2004年第1期47卷 8-16页

作者： TANG Zhilie1. XING Da2 & LIU Songhao2 1. department of Physics, South{1. Normal university, Guangzhou 51.631.{1. 2. School for information and Optoelectronic Science and engineering, South{1. Normal university, Guangzhou 51.631.{1. Correspondence should be addressed to Tang Zhilie (email: tangzhl@***) Received April 23, 2003 1. department of Physics South China Normal University 510631 Guangzhou China 2. School for information and Optoelectronic Science and {1. South China Normal University 510631 Guangzhou China

The imaging theory of nonlinear second harmonic generation (SHG) and third harmonic generation (THG) in confocal microscopy is presented in this paper. The nonlinear effect of SHG and THG on the imaging properties of confocal microscopy has been analyzed in detail by the imaging theory. It is proved that the imaging process of SHG and THG in confocal microscopy, which is different from conventional coherent imaging or incoherent imaging, can be divided into two different processes of coherent imaging. The three-dimensional point spread functions (3D-PSF) of SHG and THG confocal microscopy are derived based on the nonlinear principles of SHG and THG. The imaging properties of SHG and THG confocal microscopy are discussed in detail according to its 3D-PSF. It is shown that the resolution of SHG and THG confocal microscopy is higher than that of single- and two-photon confocal microscopy.

关键词： second harmonic generation, third harmonic generation, confocal microscopy, three-dimensional point spread function.

Target tracking in wireless sensor networks using adaptive measurement quantization

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Science china({1. Sciences) 2012年第4期55卷 827-838页

作者： ZHOU Yan 1.2,LI JianXun 2 & WANG DongLi 1.1.Colleage of information {1.,Xiangtan university,Xiangtan 41.1.5,china 2 department of Automation,Shanghai Jiao Tong university,Shanghai 200240,china 1. Colleage of information {1. Xiangtan University Xiangtan 411105 China2. Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

Quantization/compression is usually adopted in wireless sensor networks (WSNs) since each sensor node typically has very limited power supply and communication *** consider the problem of target tracking in a WSN with quantized measurements in this *** is focused on the design of measurement quantizer with adaptive *** on the probability density function (PDF) of the signal amplitude measured at a random location and by maximizing the entropy,an adaptive design method for quantization thresholds is *** to the nonlinear measuring and quantization models,particle filtering (PF) is adopted in the fusion center (FC) to estimate the target *** Cram'er-Rao lower bounds (CRLBs) for tracking accuracy using quantized measurements are also ***,a simulation example on tracking single target with noisy circular trajectories is provided to illustrate the effectiveness of the proposed approach.

关键词： target tracking wireless sensor network adaptive quantization posterior Cram’er-Rao lower bound

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 {1. School, university of Science and Technology Beijing, Beijing 1.0083, china department of information and Control {1., Southwest Institute of Technology, Mianyang 621.02, china information {1. School University of Science and Technology Beijing Beijing 100083 China department of {1. 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

Notifiable infectious disease surveillance with data collected by search engine

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Journal of Zhejiang university-Science C(Computers and Electronics) 2010年第4期11卷 241-248页

作者： Xi-chuan ZHOU1.Hai-bin SHEN2 (1.0} of {1. Science and Electronic engineering,Zhejiang university,Hangzhou 31.027,china) (2School of Electrical engineering,Zhejiang university,Hangzhou 31.027,china) department of {1. Science and Electronic engineering Zhejiang University Hangzhou China School of Electrical engineering Zhejiang University Hangzhou China

Notifiable infectious diseases are a major public health concern in china,causing about five million illnesses and twelve thousand deaths every *** detection of disease activity,when followed by a rapid response,can reduce both social and medical impact of the *** aim to improve early detection by monitoring health-seeking behavior and disease-related news over the ***,we counted unique search queries submitted to the Baidu search engine in 2008 that contained disease-related search *** we counted the news articles aggregated by Baidu's robot programs that contained disease-related *** found that the search frequency data and the news count data both have distinct temporal association with disease *** adopted a linear model and used searches and news with 1.200-day lead time as explanatory variables to predict the number of infections and deaths attributable to four notifiable infectious diseases,i.e.,scarlet fever,dysentery,AIDS,and *** the search frequency data and news count data,our approach can quantitatively estimate up-to-date epidemic trends 1.–40 days ahead of the release of Chinese Centers for Disease Control and Prevention(Chinese CDC)*** approach may provide an additional tool for notifiable infectious disease surveillance.

关键词： Notifiable infectious diseases Disease surveillance Search engine

Two-dimensional water-filling power allocation algorithm for MIMO-OFDM systems

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Science china({1. Sciences) 2010年第6期53卷 1242-1250页

作者： JIANG YongQuan 1., SHEN MinFen 1.& ZHOU YuanPing 2 1.department of Electronic {1., Shantou university, Shantou 51.063, china 2 department of Electronic {1., Sichuan university, Chengdu 61.064, china 1. department of Electronic {1. Shantou University Shantou 515063 China2. Department of Electronic Engineering Sichuan University Chengdu 610064 China

Departing from the narrowband channel model, more and more researchers have recently considered the application of multiple-input multiple-output(MIMO) systems over frequency-selective fading channels in combination with the orthogonal frequency-division multiplexing(OFDM) *** this paper, we focus on the capacity of MIMO-OFDM systems and how to increase the *** has been proved that the capacity of a MIMO system with space-dimensional water-filling power allocation is greater than that of the system with uniform power *** MIMO-OFDM systems, there is an additional degree of freedom to allocate power with respect to MIMO systems:the OFDM sub-channels in *** the singular value decomposition(SVD) applied to the channel frequency response matrix, the two-dimensional water-filling power allocation algorithm for MIMO-OFDM systems is proposed based on the Lagrange method, and the corresponding capacity analysis formula is *** results show that the capacity of a MIMO-OFDM system with the proposed two-dimensional water-filling power allocation is greater than that of the system with uniform power allocation and also greater than that of the system with the one-dimensional water-filling power allocation.

关键词： MIMO-OFDM two-dimensional water-filling power allocation capacity analysis singular value decomposition(SVD)

About the convergence rates of a class of gene expression programming

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Science china({1. Sciences) 2010年第4期53卷 715-728页

作者： DU Xin1.2* & DING LiXin1.1.tate Key Laboratory of Software engineering, Wuhan {1., Wuhan 430072, china 2department of information engineering, Shijiazhuang {1. of Economics, Shijiazhuang 050031. china 1. State Key Laboratory of Software engineering Wuhan University Wuhan 430072 China2. Department of Information Engineering Shijiazhuang University of Economics Shijiazhuang 050031 China

This paper studies the convergence rates of gene expression programming based on maintaining elitist (ME-GEP) by means of Markov chain and spectrum analysis. We obtain the following results: (1. ME-GEP algorithm converges to the global optimum in probability. (2) The convergence rates of ME-GEP algorithm depend on the revised spectral radius of transition matrix of Markov chain corresponding to the algorithm. (3) The upper bounds of revised spectral radius are estimated, which are determined by the parameters of ME-GEP algorithm. (4) As an application of the theoretical results acquired in the paper, the convergence rates of ME-GEP for the polynomial function modeling problem are also analyzed, which verifies the relations between the convergence rates and the algorithm parameters.

关键词： GEP ME-GEP convergence rates Markov chain revised spectral radius