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Chinese Physics B 2012年第12期21卷 161-167页

作者：王申全冯健赵青 College of information Science and engineering Northeastern University Department of Electrical and Computer engineering University of Alberta

In this paper, the problem of delay-distribution-dependent stability is investigated for continuous-time recurrent neural networks （CRNNs） with stochastic delay. Different from the common assumptions on time delays, it is assumed that the probability distribution of the delay taking values in some intervals is known a priori. By making full use of the information concerning the probability distribution of the delay and by using a tighter bounding technique （the reciprocally convex combination method）, less conservative asymptotic mean-square stable sufficient conditions are derived in terms of linear matrix inequalities （LMIs）. Two numerical examples show that our results are better than the existing ones.

关键词： recurrent neural networks stochastic delay mean-square stability linear matrix inequal- ity

乘法倍频对锁相式莫尔条纹信号细分方法的改进

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上海交通大学学报 2009年第5期43卷 837-840,846页

作者：郭雨梅崔晋玲沈阳工业大学信息科学与工程学院沈阳110023

以研究实用性强、细分精度高的莫尔条纹信号细分方法为目的,提出乘法倍频技术与锁相式莫尔条纹信号细分方法相结合的新方案,并通过理论分析与实验仿真,验证了该方案的可行性与实用性.结果表明,所提出的新方案可改善原始信号的质量,降低... 详细信息

以研究实用性强、细分精度高的莫尔条纹信号细分方法为目的,提出乘法倍频技术与锁相式莫尔条纹信号细分方法相结合的新方案,并通过理论分析与实验仿真,验证了该方案的可行性与实用性.结果表明,所提出的新方案可改善原始信号的质量,降低对光栅传感器输出信号正交性、等幅性等方面的要求,并能提高细分精度,具有重要的实际应用价值.

关键词：乘法倍频光栅锁相细分莫尔条纹

Fault Identification for Lipschitz Nonlinear Systems

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Fault Identification for Lipschitz Nonlinear Systems

A State-Space Approach to H∞ Actuator Fault Detection for Sampled-Data Systems

2.1. Chinese Control and Decision Conference（CCDC）

作者： Fuqiang You is with school of information Science and engineering,Northeastern university,shenyang,China.Fuli Wang is with school of information Science and engineering,Northeastern university,shenyang,China.Zhizhong Mao is with school of information Science and engineering,Northeastern university,shenyang,China.Shouping Guan is with school of information Science and engineering,Northeastern university,shenyang,China.

Fault identification for a class of nonlinear systems is considered,where the nonlinear term in the system satisfies local Lipschitz *** some fault detectability conditions are satisfied,the system is first decomposed into two subsystems,where one is coupled with and another is decoupled from *** asymptotic state observer is then designed for the fault-coupled subsystem,in which a fictitious input is introduced to assure the state observer is asymptotic *** is proven that the actuator faults would be reconstructed from the fictitious input under steady *** stability analysis of the state observer and fault identification scheme design is given in a constructive manner and finally such a procedure is equivalent to solving a set of linear matrix inequalities.

关键词： Fault identification nonlinear systems asymptotic observer linear matrix inequality

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A State-Space Approach to H∞ Actuator Fault Detection for S...

Application of the Bacterial Chemotaxis Algorithm for Solving Nonlinear Optimal Control Problem

2.1. Chinese Control and Decision Conference（CCDC）

Actuator fault detection problem for sampled-data systems is investigated in an H∞ setting,where the effect from exogenous disturbance and uncertainties in the initial state to the residual is attenuated in a prescribed *** a problem is first formulated as a modified sampled-data control problem and it turns out the fault detector owns the jump system’s *** sufficient existence condition and the design algorithm for the detector are then both provided in terms of solution to a set of Riccati differential equation with finite discrete *** proposed approach for sampled-data actuator fault detection problem is a simple state-space method and it improves the existed results in two ***,robustness to the measurement noise and uncertainties in the initial state is ***,parameters of the sampled-data system are allowed to be time-varying.

关键词： Sampled-data systems fault detection Riccati equation

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Application of the Bacterial Chemotaxis Algorithm for Solvin...

Land use structural optimization of Lilin based on GMOP-ESV

第24届中国控制与决策会议

作者： Ping Ren 1 , Liqun Gao 2 , Nan Li 3 1. school of information engineering, shenyang university, shenyang 1100442. school of information Science and engineering, Northeastern university, shenyang 1100043. shenyang university, shenyang 110044, China

In this paper, the nonlinear optimal control problem is formulated as a multi-objective mathematical optimization problem. Bacterial Chemotaxis （BC） algorithm is one of the new heuristic algorithms based on colony intelligence. The BC optimization algorithm is introduced for the first time in solving the nonlinear optimal control problem. A case on the nonlinear optimal control problem is presented to show the methodology’s feasibility and efficiency, compared with the existing optimal planning methods, the search time of the BC optimization algorithm is shorter and the result is close to the ideal solution, simultaneously.

关键词： Nonlinear optimal control problem Multi-objective mathematical optimization problem Bacterial chemotaxis algorithm Application

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中国有色金属学会会刊：英文版 2011年第S3期21卷 738-742页

作者： ZHANG He-bing, ZHANG Xiao-hu school of Surveying & Land information engineering, Henan Polytechnic university, Jiaozuo 454000, China school of Surveying & Land information engineering Henan Polytechnic University Jiaozuo 454000 China

Land use structural optimization is an effective approach to realize land sustainable utilization and allocate limited land resource rationally. Grey multiple objectives programming (GMOP) model based on China terrestrial ecosystem service value was constructed and applied to Lilin town. The result shows that GMOP model has more practical applicability and takes ecologic, social and comprehensive benefit into consideration. There are three programs after optimization. Program Ⅰ is comprehensive improvement and constructing ecological economy type, program Ⅱ is gross cultivated land dynamic balance type and program Ⅲ is compromise type. There are still problems in programs Ⅱ and Ⅲ, such as distribution in disorder, land left unused or abandoned. Based on the benefits above, Program Ⅰ>Program Ⅲ> Program Ⅱ. Program Ⅰ is the optimal case. Its comprehensive benefit is 8.43208×107 RMB yuan/a.

关键词： land use structure optimization grey multiple objective programming ecosystem service value Lilin town

Porous bulk metallic glass fabricated by powder hot pressing

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International Journal of Minerals,Metallurgy and Materials 2007年第S1期15卷 59-63页

作者： Keqiang Qiu1), Bo Yu2), and Yinglei Ren1) 1) school of Materials Science and engineering, shenyang university of Technology, shenyang 110023, China 2) shenyang Research Institute of Foundry, shenyang 110022, China

A synthesis method for the production of porous bulk metallic glass (BMG) was introduced. This method utilizes the su- perplastic forming ability of amorphous powder in the supercooled liquid (SCL) state and intenerating salt mixture as a placeholder to produce BMG foam by using a hot die pressing method. Scanning electron microscope (SEM), X-ray diffraction (XRD) and dif- ferential scanning calorimetry (DSC) were employed to characterize the morphologies of foaming structure, the crystallization and the percentage of crystallization of the as-produced porous BMG. The results suggested that the formation of porous structure by su- perplastic forming process is feasible. Good bonding effect was observed between amorphous powder particles. Less than 6.5% of crystalline phases were formed during hot pressing, and less than 5.5% of residual salt was enclosed in the foam. To remove any re- sidual salt particles, salt preforms with three-dimensional network and good connectivity is necessary.

关键词： porous bulk metallic glass hot pressing placeholders superplastic forming

Performance comparison and parametric study on spiral groove gas film face seals

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Science China(Physics,Mechanics & Astronomy) 2004年第Z1期47卷 29-36页

作者： LIU Yuchuan, SHEN Xinmin, XU Wanfu & WANG ZhiliState Key Laboratory of Tribology, Tsinghua university, Beijing 100084, China school of Mechanical engineering and Automation, Beijing university of Aeronautics and Astronautics, Beijing 100083, China Lubrication Technology Research Center, shenyang Institute of Technology, shenyang 110015, China Tsing Hua Univ State Key Lab Tribol Beijing 100084 Peoples R China Beijing Univ Aeronaut & Astronaut Sch Mech Engn & Automat Beijing 100083 Peoples R China shenyang Inst Technol Lubricat Technol Res Ctr Shenyang 110015 Peoples R China

Several spiral groove gas film face seals (SGFS) with different layouts are compared quantitatively to analyze their merits and faults and application behaviors. In addition, a parametric study on downstream mode SGFS is conducted to determine its optimal parameters under certain working conditions. In tne computation of gas film pressure on the face, finite element method (FEM) is applied to adapt to complicated geometrical boundary.

关键词： spiral groove, gas film face seals, parameter study, performance comparison, finite element method.

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

An improved reduced-rank STAP interference suppression method in design of GNSS receivers

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Science China(information Sciences) 2012年第10期55卷 2329-2342页

作者： GONG WenFei & SUN Xin school of Electronics and information engineering,Beijing Jiaotong university,Beijing 100044,China school of Electronics and information engineering Beijing Jiaotong University Beijing China

In this paper,we address the problem of interference cancellation in global positioning system(GPS) receiver using an adaptive reduced-rank space-time adaptive processing(STAP) interference suppression method based on multistage nested Wiener filter(MSNWF).This improved adaptive reduced-rank method is based on the improved Gerschgorin radii ***,the cross-correlations between the desired signals of the adjacent stages of MSNWF are directly used to calculate the Gerschgorin radii instead of employing the eigenvalue decomposition of the covariance ***,a heuristic decision rule based on Gerschgorin disk estimator(GDE) is employed to estimate the rank of interference *** optimal rank can be adaptively selected without increasing the *** and results of the experiment show that the proposed method further reduces the computation of STAP and enhances its real-time property with the interference suppression performance unaffected.

关键词： global positioning system reduced-rank space-time adaptive processing multistage nested Wiener filter Gerschgorin disk estimator