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中国科学：技术科学英文版 2011年第S1期54卷 185-191页

作者： LIU HaoWu 1,2.CHEN Jiang 2.SUN Man 3 & DING Rui 2.1 State Key Laboratory of Hydraulics and Mountain River engineering,sichuan university,Chengdu {2.,china 2.school of Water Resource Hydropower,sichuan university,Chengdu {2.,china 3 school electrical engineering and information,sichuan university,Chengdu {2.,china sichuan Univ State Key Lab Hydraul & Mt River Engn Chengdu 610065 Peoples R China sichuan Univ Sch Water Resource Hydropower Chengdu 610065 Peoples R China sichuan Univ Sch Elect Engn & Informat Chengdu 610065 Peoples R China

The micromechanical behaviors and mechanics-optics coupling effects of optic-fiber-concrete complex in the distributed optic-fiber sensing concrete-crack technology,which was used in health monitoring of Wu Gorge Bridge on Yangtze River and a large dam successfully,have been investigated.A micromechanical theoretical analysis method and micromechanical frictional contact bi-interface model,as well as a modified optical theoretical analysis method of the mechanics-optics coupling effects are presented.A series of verification experiments,including mechanical experiments and mechanics-optics coupling experiments,have been *** results of micromechanical theoretical analysis and the analysis of the modified theory of mechanics-optics coupling along with mechanical and optical experimental data are shown to be in close *** the micromechanical theory and the modified theory of mechanics-optics coupling with their analysis methods can not only enhance credibility of this novel distributed sensing technology but also provide a way to understand its sensing mechanism and optimize its technical details and system.

关键词： optic-fiber sensing mechanics-optics coupling micromechanics health monitoring concrete structure crack detection

A novel evolving model for power grids

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Science china(Technological Sciences) 2010年第10期53卷 2862-2866页

作者： LIU Xuan, LIU TianQi & LI XingYuan school of electrical {2. and Automation, sichuan university, Chengdu 610065, china 1. school of electrical {2. and Automation Sichuan University Chengdu 610065 China

In this paper,a novel power grid evolving model,which can well describe the evolving property of power grids,is presented. Based on the BA model,motivated by the fact that in real power grids,connectivity of node not only depends on its degree,but also is influenced by many uncertain factors,so we introduce the subconnection factor K for each node. Using the mean-field theory,we get the analytical expression of power-law degree distribution with the exponent γ∈ (3,∞ ). Finally,simulation results show that the new model can provide a satisfactory description for empirical characteristics of power network,and power network falls somewhere in between scale-free network and uncertain network.

关键词： power grid evolving model scale-free

Design,analysis and control of hybrid excited doubly salient stator-permanent-magnet motor

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Science china(Technological Sciences) 2010年第1期53卷 188-199页

作者： ZHU XiaoYong1,2.& CHENG Ming1 1 engineering Research Center for Motion Control of MOE,school of {2. engineering,Southeast university,Nanjing 2.0096,china 2.school of {2. and information engineering,Jiangsu university,Zhenjiang 2.2.13,china 1. engineering Research Center for Motion Control of MOE School of Electrical Engineering Southeast University Nanjing 210096 China2. School of Electrical and Information Engineering Jiangsu University Zhenjiang 212013 China

In this paper,a new hybrid excited doubly salient stator-permanent-magnet motor is proposed,where both permanent magnets and DC field windings are located in the *** theory,the mathematical model and design method of the motor are *** corresponding output power equation and the relationship between the flux control capability and the extended speed range are deduced in *** using an efficient "one-step" three-dimensional(3D) finite element method,the electromagnetic performances are analyzed,in which the leakage flux outside the stator circumference and end-effect are taken into *** on the operation principle of the motor,the control strategy and scheme are developed and implemented *** experimental results and finite element analysis show that the proposed motor not only maintains the advantages of doubly salient permanent magnet motors,but also offers high energy efficiency over a wide speed range,which makes the motor an interesting candidate for electric vehicles.

关键词： stator permanent magnet motor hybrid excitation doubly salient finite element method flux weakening control

Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1, 2. ZHANG Yin-ling1, 2. WANG Fei 1 ,2. ZHANG Zhen-hui 3, GUO Yu-xiang1, 2.1. Key Laboratory of Mine Spatial information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003, {2. 2. school of Surveying and land information engineering, Henan Polytechnic university, Jiaozuo 454003, {2. 3. Qingdao Branch of Naval Aeronautical engineering Institute, Qingdao 2.6041, {2. Henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China Henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

The study of adsorption gas sensor based carbon nanotube film

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Science china(Technological Sciences) 2005年第4期48卷 372-384页

作者： LI Xin1, LIU Junhua2.& ZHU Changchun1 1. school of Electronic and information {2., Xi’an Jiaotong university, Xi’an 710049, china 2. school of Electric {2., Xi’an Jiaotong university, Xi’an 710049, china 1. school of Electronic and information {2. Xi’an Jiaotong University 710049 Xi’an China 2. school of Electric engineering Xi’an Jiaotong University 710049 Xi’an China

The study of gas sensitivity of multi-wall carbon nanotubes (MWNTs), which is deposited by low press chemical vapor deposition (LPCVD), is presented. The results show that the pure MWNTs are not sensitive to the gases measured, while the composite film consisting of the MWNTs and silicon dioxide is sensitive to the methane, the hydrogen and the acetylene. The MWNTs and silicon dioxide composite film have the capacitance characteristic because of the formation of Schottky junctions within the MWNTs. The chemistry adsorption of the gas measured on the surface of the MWNTs affects the space discharge area of the Schottky junction, so that the dielectric constant changes with the gas concentration. That is why the gas is sensed.

关键词： gas sensor, carbon nanotubes, low press chemical vapor deposition, scatter.

Dynamic scheduling model of computing resource based on MAS cooperation mechanism

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Science in china(Series F) 2009年第8期52卷 1302-1320页

作者： JIANG WeiJin1,2. ZHANG LianMei3 & WANG Pu4 1 school of Computer and Electronic engineering, Hunan {2. of Commerce, Changsha 4102.5, china 2.school of information engineering, Xiangtan {2., Xiangtan 411000, china 3 electrical engineering College, Wuhan {2., Wuhan 430072. china 4 school of Commerce, Central South {2., Changsha 410083, china 1. school of Computer and Electronic engineering Hunan University of Commerce Changsha 410205 China 2. school of information {2. Xiangtan University Xiangtan 411000 China 3. electrical engineering College Wuhan University Wuhan 430072 China 4. school of Commerce Central South University Changsha 410083 China

Allocation of grid resources aims at improving resource utility and grid application performance. Currently, the algorithms proposed for this purpose do not fit well the autonomic, dynamic, distributive and heterogeneous features of the grid environment. According to MAS （multi-agent system） cooperation mechanism and market bidding game rules, a model of allocating allocation of grid resources based on market economy is introduced to reveal the relationship between supply and demand. This model can make good use of the studying and negotiating ability of consumers＇ agent and takes full consideration of the consumer＇s behavior, thus rendering the application and allocation of resource of the consumers rational and valid. In the meantime, the utility function of consumer is given; the existence and the uniqueness of Nash equilibrium point in the resource allocation game and the Nash equilibrium solution are discussed. A dynamic game algorithm of allocating grid resources is designed. Experimental results demonstrate that this algorithm diminishes effectively the unnecessary latency, improves significantly the smoothness of response time, the ratio of throughput and resource utility, thus rendering the supply and demand of the whole grid resource reasonable and the overall grid load balanceable.

关键词： multi-agent system (MAS) resource scheduling model evolutionary game cooperation mechanism utility function

An output delay approach to fault estimation for sampled-data systems

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Science china(information Sciences) 2012年第9期55卷 2128-2138页

作者： WEN ChengLin 1,QIU AiBing 2.& JIANG Bin 3 1 Institute of information and Control,Hangzhou Dianzi university,Hangzhou 310018,{2. 2.school of electrical engineering,Nantong university,Nantong 2.6019,{2. 3 College of Automation engineering,Nanjing university of Aeronautics and Astronautics,Nanjing 2.0016,{2. 1. Institute of information and Control Hangzhou Dianzi University Hangzhou 310018 China2. School of Electrical Engineering Nantong University Nantong 226019 China3. College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The problem of fault estimation for a class of non-uniformly sampled-data systems is investigated from the time delay point of view in this ***,the output delay approach is employed to model the sampled-data system as a continuous-time one with time-varying delay ***,based on the analysis of the inapplicability of the adaptive fault diagnosis observer in such class of time-delay systems,a novel augmented fault estimation observer design method is proposed to guarantee the exponential convergence of the estimation ***,an extension to the case of time varying fault estimation for the noisy sampled-data systems is ***,simulation results of a flight control system are presented to demonstrate the effectiveness of the proposed method.

关键词： fault estimation non-uniformly sampled-data augmented observer output delay

Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2. YU Yi-ju3 1. school of Surveying and Landing information {2., Henan Polytechnic university, Jiaozuo 454003, china 2. College of Geoscience and Surveying {2., china university of Mining and Technology, Beijing 100083, china 3. Surveying and Mapping Press, Beijing 100045, china [a] school of Surveying and Landing information {2. Henan Polytechnic University Jiaozuo 454003 China [b] College of Geoscience and Surveying engineering China University of Mining and Technology Beijing 100083 China [c] Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.131 mm and vertical direction is ±0.192.mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

An aperiodic phenomenon of the unscented Kalman filter in filtering noisy chaotic signals

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Progress in Natural Science:Materials International 2007年第10期17卷 1235-1240页

作者： Fan Hongjuan1, Feng Jiuchao1,2. Xie Shengli2.and Wang Shiyuan1(1. Faculty of Electronic and information engineering ,Southwest {2., Chongqing 400715, china 2. school of Electronic and information engineering, South china {2. of Technology, Guangzhou 510641, china) Faculty of Electronic and information engineering Southwest University Chongqing 400715 China school of Electronic and information {2. South China University of Technology Guangzhou 510641 China

A non-periodic oscillatory behavior of the unscented Kalman filter (UKF) when used to filter noisy contaminated chaotic signals is reported. We show both theoretically and experimentally that the gain of the UKF may not converge or diverge but oscillate aperiodically. More precisely, when a nonlinear system is periodic, the Kalman gain and error covariance of the UKF converge to zero. However, when the system being considered is chaotic, the Kalman gain either converges to a fixed point with a magnitude larger than zero or oscillates aperiodically.

关键词： chaos unscented Kalman filter Lyapunov exponents aperiodicity.

Stability of impulsive stochastic functional differential systems in terms of two measures via comparison approach

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Science china(information Sciences) 2012年第6期55卷 1313-1322页

作者： YAO FengQi 1,2.& DENG FeiQi 1 1 Institute of System engineering,South china {2. of Technology,Guangzhou 510640,china 2.school of electrical engineering and information,Anhui {2. of Technology,Maanshan 2.3032.china 1. Institute of System engineering South China University of Technology Guangzhou 510640 China2. School of Electrical Engineering and Information Anhui University of Technology Maanshan 243032 China

Comparison principles for general impulsive stochastic functional differential systems are *** the comparison principles and the theory of differential inequalities,stability and instability,involving two measures,of impulsive stochastic functional differential systems are *** stability and instability criteria are obtained,and two examples are also given to illustrate our results.

关键词： stochastic systems impulsive functional differential systems comparison principle stability in terms of two measures instability