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Estimation of underdetermined mixing matrix based on support vector machine

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Progress in Natural science:Materials International 2007年第11期17卷 1363-1367页

作者： Yang Zuyuan and Xie Shengli(school of Electrics & information engineering, South china university of technology, Guangzhou 510641, china) school of Electrics & information engineering South China University of Technology Guangzhou 510641 China

In underdetermined blind source separation (BSS), a novel algorithm based on extended support vector machine (SVM) is proposed to estimate the mixing matrix in this paper, including the number of the active sources. Instead of traditional clustering algorithms, it mainly takes the modulus of observations and the number in each direction of arrival, without any prior knowledge about the sources except for sparsity, and it is not sensitive to the initial values. Simulations are given to illustrate availability and robustness of our algorithm.

关键词： underdetermined BSS SVM clustering

Microwave Disinfection in a Ventilation and Air-Conditioning System

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湖南大学学报（自然科学版） 2009年第S1期36卷 55-59页

作者： LU Zhen1,2,ZHANG Ji-li1,MA Liang-dong1,HE Juan3(1.school of Civil & Hydraulic engineering,Dalian university of technology,Dalian,Liaoning 116023,china 2.Municipal and Environmental engineering Research Center,shenyang Jianzhu university,shenyang,Liaoning 110168,china 3.school of Municipal & Environmental engineering,Harbin Institute of technology,Harbin,Heilongjiang 150090,china) school of Civil and Hydraulic engineering Dalian University of Technology Dalian 116023 China Municipal and Environmental engineering Research Center Shenyang Jianzhu University Shenyang 110168 China school of Municipal and Environmental engineering Harbin Institute of Technology Harbin 150090 China

Because of its broad spectrum and high efficiency,the microwave disinfection was used to control the airborne microbial contaminates in VAC *** microwave disinfection devices were developed combined with air filter,the design and calculation method was presented,and the disinfection effects on White staphylococcus,Staphylococcus aureus,Bacillus Subtilis,Escherichi coli were *** results show that the major influence factors on disinfection effect are microwave power,water-content of filter material,disinfecting *** 15 min,the kill ratio is >90%,and the log value is >*** microwave field is uniform and the kill effect of bacteria on each surface of filter is the same,without statistically significant difference.

关键词： VAC system microwave disinfection airborne microbe microwave power kill ratio

Stabilization of Chaotic Time Series by Proportional Pulse in the System Variable Based on Genetic Algorithm

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 228-229页

作者： Qing Li Deling Zheng Jianlong Zhou(information engineering school, university of science and technology Beijing, Beijing 100083, china)(Handan iron and Steel Co., Handan 056015, china) information engineering school University of Science and Technology Beijing Beijing 100083 China Handan Iron and Steel Co. Handan 056 015 China

The PPSV (Proportional Pulse in the System Variable) algorithm is a convenient method for the stabilization of the chaotic time series. It does not require any previous knowledge of the system. The PPSV method also has a shortcoming, that is, the determination off. is a procedure by trial and error, since it lacks of optimization. In order to overcome the blindness, GA (Genetic Algorithm), a search algorithm based on the mechanics of natural selection and natural genetics, is used to optimize the λi The new method is named as GAPPSV algorithm. The simulation results show that GAPPSV algorithm is very efficient because the control process is short and the steady-state error is small.

关键词： stabilization chaotic time series genetic algorithm

Surface characteristics of rapidly solidified nickel-based superalloy pow-ders prepared by PREP

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Rare Metals 2003年第4期22卷 309-314页

作者： CHEN Huanming , HU Benfu , and LI Huiying1) school of Materials science and engineering, university of science and technology Beijing, Beijing 100083, china2) school of Physics and Electrical information engineering, Ningxia university, Yinchuan 750021, china school of Materials science and engineering University of Science and Technology Beijing Beijing 100083 Chins

The surface microstructure and the surface segregation of FGH 95 nickel-basedsuperalloy powders prepared through plasma rotating electrode processing (PREP) have beeninvestigated by using SEM and AES. The results indicate that the surface microstructure of powderschanges from dendrite into cellular stricture as the particle size of powders decrease, and thepredominant precipitates solidified on the particle surfaces were identified as MC' type carbidesenriched with Nb and Ti. It was also indicated that along with the depth of particle surfaces, thesegregation layer of S, C and O elements are thick, and that of Ti, Cr elements are thin for largesire powders while they are in reverse for median size particles.

关键词： FGH 95 nickel-based superalloy powders surface characteristics microstructure plasma rotating electrode processing

Fuzzy H∞ Filter Design for a Class of Nonlinear Systems with Time Delays via LMI

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自动化学报 2005年第3期 64-71页

作者： LUN Shu-Xian~(1’2) ZHANG Hua-Guang~1 ~1(school of information science and engineering,Northeastern university,shenyang 110004)~2(school of information science and engineering,Bohai university,Jinzhou 110004)

This paper develops fuzzy Hfilter for state estimation approach for nonlinear discrete- time systems with multiple time delays and unknown bounded *** design a stable fuzzy Hfilter based on the Takagi-Sugeno (T-S) fuzzy model,which assures asymptotic stability and a prescribed Hindex for the filtering error *** condition for the existence of such a filter is established by solving the linear matrix inequality (LMI) *** LMI problem can be efficiently solved with global convergence using the interior point *** examples are provided to illustrate the design procedure of the proposed method.

关键词： Nonlinear systems H_∞ filter state estimation Takagi-Sugeno fuzzy model time delays linear matrix inequality(LMI)

基于VRML的可视化虚拟场景生成工具的研究

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系统仿真学报 2005年第1期17卷 72-74页

作者：魏东黄有群合肥工业大学计算机与信息学院安徽合肥230009 沈阳工业大学信息科学与工程学院辽宁沈阳110023

构造和生成VRML虚拟场景的流行工具和国内的研究多保持在用VRML文本编辑器直接书写程序的方式上,研究通过在场景上的图形操作,非编程地生成VRML场景的实现方法,并开发了一个实用系统。该方法不需要用户了解VRML语法,生成过程方便快捷。

关键词：虚拟场景 VRML 可视化生成工具

Delay-dependent robust H∞ control for uncertain fuzzy hyperbolic systems with multiple delays

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Progress in Natural science:Materials International 2008年第1期18卷 97-104页

作者： Huaguang Zhanga ,*,Qingxian Gong a,b ,Yingchun Wang a aschool of information science and engineering,Northeastern university,shenyang 110004,china bDepartment of Electrical engineering,Changchun Institute of technology,Changchun 130012,china school of information science and engineering Northeastern University Shenyang 110004 China Department of Electrical engineering Changchun Institute of Technology Changchun 130012 China

The robust H∞ control problem was considered for a class of fuzzy hyperbolic model(FHM)systems with parametric uncertainties and multiple ***,FHM modeling method was presented for time-delay nonlinear ***,by using Lyapunov–Krasov- skii approaches,delay-dependent suficient condition for the existence of a kind of state feedback controller was proposed,which was expressed as linear matrix inequalities(LMIs).The controller can guarantee that the resulting closed-loop system is robustly asymptot- ically stable with a prescribed H∞ performance level for all admissible uncertainties and ***,a simulation example was provided to illustrate the effectiveness of the proposed approach.

关键词： Fuzzy hyperbolic model Robust H1 control Asymptotical stability Linear matrix inequality Uncertain time-delay system

Performance-based methodology for assessing seismic vulnerability and capacity of buildings

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Earthquake engineering and engineering Vibration 2010年第2期9卷 157-165页

作者： Lin Shibin1, Xie Lili1, 2,Gong Maosheng1,2 and Li Ming1,3 1.Institute of engineering Mechanics,china Earthquake Administration, Harbin 150080, china 2.school of Civil engineering,Harbin Institute of technology,Harbin 150090, china 3.school of Civil engineering,shenyang Jianzhu university,shenyang 11016, china Institute of engineering Mechanics China Earthquake Administration Harbin 150080 China

This paper presents a performance-based methodology for the assessment of seismic vulnerability and capacity of buildings. The vulnerability assessment methodology is based on the HAZUS methodology and the improved capacity- demand-diagram method. The spectral displacement (Sd) of performance points on a capacity curve is used to estimate the damage level of a building. The relationship between Sd and peak ground acceleration (PGA) is established, and then a new vulnerability function is expressed in terms of PGA. Furthermore, the expected value of the seismic capacity index (SCev) is provided to estimate the seismic capacity of buildings based on the probability distribution of damage levels and the corresponding seismic capacity index. The results indicate that the proposed vulnerability methodology is able to assess seismic damage of a large number of building stock directly and quickly following an earthquake. The SCev provides an effective index to measure the seismic capacity of buildings and illustrate the relationship between the seismic capacity of buildings and seismic action. The estimated result is compared with damage surveys of the cities of Dujiangyan and Jiangyou in the M8.0 Wenchuan earthquake, revealing that the methodology is acceptable for seismic risk assessment and decision making. The primary reasons for discrepancies between the estimated results and the damage surveys are discussed.

关键词： performance-based vulnerability building damage seismic capacity software HAZUS

Approximately optimal tracking control for discrete time-delay systems with disturbances

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Progress in Natural science:Materials International 2008年第2期18卷 225-231页

作者： Gongyou Tang a,,Huiying Sun b,Haiping Pang c a College of information science and engineering,Ocean university of china,Qingdao 266100,china b College of information and Electrical engineering,Shandong university of science and technology,Qingdao 266510,china c College of Automation and Electronic engineering,Qingdao university of science and technology,Qingdao 266042,china College of information science and engineering Ocean University of China Qingdao 266100 China College of information and Electrical engineering Shandong University of Science and Technology Qingdao 266510 China College of Automation and Electronic engineering Qingdao University of Science and Technology Qingdao 266042 China

Optimal tracking control (OTC) for discrete time-delay systems affected by persistent disturbances with quadratic performance index is considered. By introducing a sensitivity parameter,the original OTC problem is transformed into a series of two-point boundary value (TPBV) problems without time-advance or time-delay terms. The obtained OTC law consists of analytic feedforward and feedback terms and a compensation term which is the sum of an infinite series of adjoint vectors. The analytic feedforward and feedback terms can be found by solving a Riccati matrix equation and two Stein matrix equations. The compensation term can be obtained by using an iteration formula of the adjoint vectors. Observers are constructed to make the approximate OTC law physically realizable. A simulation example shows that the approximate approach is effective in tracking the reference input and robust with respect to exogenous persistent disturbances.

关键词： Discrete systems Time-delay systems Disturbances Optimal control Tracking control