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Stationary Classical Chaos of Trapped Two-Component Bose-Einstein Condensates in 1-D Optical Lattice Potentials

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Communications in Theoretical Physics 2007年第7期48卷 125-131页

作者： FANG Jian-Shu LIU Wing-Ki ZHU Shan-Hua1 institute of Physics,Hunan University of Technology,zhuzhou 412008,China2 Department of Physics,Hunan Normal University,Changsha 410081,China3 Department of Physics,University of Waterloo,Waterloo,Ontario,Canada N2L 3G1 institute of Physics Hunan University of Technology Zhuzhou 412008 China

We study the nonlinear dynamics of two-component Bose-Einstein condensates in one-dimensional pe-riodic optical lattice *** stationary state perturbation solutions of the coupled two-component nonlinearSchr?dinger/Gross-Pitaevskii equations are constructed by using the direct perturbation *** analysisrevels that the perturbation solution is the chaotic one,which indicates the existence of chaos and chaotic region inparameter *** corresponding numerical calculation results agree well with the analytical *** applying thechaotic perturbation solution,we demonstrate the atomic spatial population and the energy distribution of the systemare chaotic generally.

关键词： stationary state classical chaos two-component Bose-Einstein condensates optical lattice potential

Condition monitoring and fault diagnosis strategy of railway point machines using vibration signals

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Transportation Safety and Environment 2023年第2期5卷 27-37页

作者： Yongkui Sun Yuan Cao Haitao Liu Weifeng Yang Shuai Su National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong UniversityBeijing 100044China crrc zhuzhou institute Co Ltd Zhuzhou 412001HunanChina Frontiers Science Center for Smart High-speed Railway System Beijing Jiaotong UniversityBeijing 100044China

Condition monitoring of railway point machines is important for train operation safety and *** to the fields of mechanical equipment fault detection,this paper proposes a fault detection and identification strategy of railway point machines via vibration signals.A comprehensive feature distilling approach by combining variational mode decomposition(VMD)energy entropy and time-and frequency-domain statistical features is presented,which is more effective than single type of *** optimal set of features was selected with ReliefF,which helps improve the diagnosis *** vector machine(SVM),which is suitable for a small sample,is adopted to realize *** diagnosis accuracy of the proposed method reaches 100%,and its effectiveness is verified by experiment *** this paper,vibration signals are creatively adopted for fault diagnosis of railway point *** presented method can help guide field maintenance staff and also provide reference for fault diagnosis of other equipment.

关键词： railway point machines condition monitoring variational mode decomposition(VMD)energy entropy statistical features

Process of electroless plating Cu-Sn-Zn ternary alloy

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中国有色金属学会会刊：英文版 2006年第1期16卷 223-228页

作者：何新快陈白珍胡更生邓凌峰周宁波田文增 School of Packaging and Printing Zhuzhou Institute of Technology Zhuzhou 412008 China School of Metallurgical Science and Engineering Central South University Changsha 410083 China

Cu-Sn-Zn ternary alloy layer with 10 μm thickness was prepared through electroless plating method. The influences of process conditions including the concentration of metallic salts, reductant and complex agent on Cu-Sn-Zn alloy were studied in details. The stability to bear color changes and corrosion resistance of Cu-Sn-Zn film layer were studied through air-exposure experiment and electrochemical analyses test respectively. The results show that the performances of Cu-Sn-Zn film layer are obviously superior to brass matrix. By use of SEM,EDS and XRD, the morphology, microstructure and chemical composition were investigated. The results show that complex agent can increase the content of Sn and Zn, improve the evenness and compactness and decrease needle holes, therefore the properties of electroless plating layer such as the stability to bear color changes and corrosion resistance are improved remarkably. The probable mechanism of complex agent was discussed.

关键词： Cu-Sn-Zn 铜合金三元合金镀层腐蚀抗力

New Lyapunov-Krasovskii Functional for Stability Analysis of Linear Systems with Time-Varying Delay

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Journal of Systems Science & Complexity 2021年第2期34卷 632-641页

作者： LIN Huichao ZENG Hongbing WANG Wei institute of Electrical and Information Engineering Hunan University of TechnologyZhuzhou 412008China

This paper focuses on the problem of delay-dependent stability of linear systems with time-varying delay.A new delay-product-type augmented Lyapunov-Krasovskii functional(LKF)is *** on the LKF and by employing a generalized free-matrix-based integral inequality,less conservative delay-dependent stability criteria are ***,two well-known numerical examples are used to confirm the effectiveness and the superiority of the presented stability criteria.

关键词： Augmented Lyapunov-Krasovskii functional linear matrix inequality(LMI) stability analysis time-delay system

Technology of black coloring for stainless steel by electrochemical method

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Journal of Central South University of Technology 2006年第2期13卷 135-140页

作者：何新快陈白珍李小东胡更生吴璐烨田文增 School of Metallurgical Science and Engineering Central South University Changsha 410083 ChinaSchool of Packaging and PrintingZhuzhou Institute of Technology Zhuzhou 412008China School of Metallurgical Science and Engineering Central South University Changsha 410083 China School of Packaging and Printing Zhuzhou Institute of Technology Zhuzhou 412008China

The technology of black coloring for stainless steel by electrochemical method was studied. The optimum bath compositions and operating conditions were obtained as follows: 4050g/L K2Cr2O7 , 1520g/L MnSO4, 1520g/L （NH4）2SO4, 2040g/L H3BO3, 2030 g/L additive A, 2 g/L （NH4）6Mo7O 24 ; time 920 min; temperature 1530℃; potential 3V and current density 12mA/cm 2 . The effects of the compositions of the bath on the quality of black colored film were discussed. The influences of passivation process on the black coloring velocity and performances of black colored film layer were investigated. The results show that the passivation process can improve the corrosion resistance and the stability to bear color-change; （NH4）2SO4 can control the black coloring velocity and prolong black coloring bath life remarkably; and additive A can improve the evenness and compactness of black colored film layer. The results of scanning electron microscopy and energy dispersive spectra show that the microstructure is of cylindrical lump, the filling process can decrease the crackles, and the main elements of black colored film are Fe, Cr, Mn and Ni.

关键词： stainless steel electrochemical method black coloring corrosion resistance

Small-signal Analysis of DC Microgrid and Multi-objective Optimization Segmented Droop Control Suitable for Economic Dispatch

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Journal of Modern Power Systems and Clean Energy 2020年第3期8卷 564-572页

作者： Haiyuan Liu Yingjie Wang Min Wang Yinan Guo Jiashi Wang Gang Shen Guoqiang Liao School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221000China School of Electrical and Power Engineering China University of Mining and TechnologyXuzhou 221000China School of Mechanical Engineering China University of Mining and TechnologyXuzhou 221000China crrc zhuzhou Locomotive Co. Ltd.Zhuzhou 412001China

To obtain a larger controllable range of output/input power of droop-control sources,a multi-objective optimization segmented droop control suitable for economic dispatch for a DC microgrid is *** to the small-signal analysis,the worst point of the stability in the droop-control curve is determined through the analysis of a simplified model with multiple droop-control *** considering the worst points of stability as constraints,an elitist non-dominated sorting genetic algorithm is used to search the better turning points of the proposed droop-control curves after obtaining the new rated operation points from the system-layer economic ***,optimization objectives,including the influence of eliminating the line resistance and capacity matching,are considered in the search ***,the simulation results of the DC microgrid simulation model based on RT-Lab are presented to support the stability conclusion and proposed droop control.

关键词： Small signal DC microgrid droop control elitist non-dominated sorting genetic algorithm(NSGA-П)

Dividing and setting strategy of improving calculation efficiency for needle electrode corona discharge with a large-scale space

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High Voltage 2022年第3期7卷 429-438页

作者： Dingchen Li Chuan Li Jiawei Li Pengyu Wang Zhi Liu Wendi Yang Ming Zhang Yong Yang Kexun Yu International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical Engineering and ElectronicsHuazhong University of Science and TechnologyWuhanChina Digital Grid Research institute of China Southern Power Grid GuangzhouChina zhuzhou crrc Times Electric Co. Ltd.(TEC)ZhuzhouChina

Needle electrodes are widely used in the research of corona *** at the problem of needle electrode discharge in a large-scale space(tens or even hundreds of centimetres),a hybrid model was proposed in the previous ***,its indis-pensable multiple iterations result in huge computation and further limit its wide ***,a strategy to improve the computing efficiency by setting initial values in different computational domains is put forward in this *** types of setting initial values(global constant,partition constant and partition exponent)are simulated and compared in *** calculation results show that the calculation efficiency can be increased by 1.4 times simply through setting initial values of charged particles as different constants for the divided subdomains,and further be improved by 4.3 times by setting those in the ionization region as an exponential *** extension of the pro-posed strategy has also been discussed under various voltages,which shows that the results under other voltages can be quickly obtained based on the fitted coefficients under a specific voltage,and the improvement can reach up to 10 *** accuracy of calculated results has been demonstrated by a needle-plate electrode device with a vertical distance of 25 *** research provides an effective strategy for improving the computing efficiency of corona discharge in a large-scale space,and implies the potential in optimizing the analyses of complex electrodes.

关键词： electrode calculation partition

An Integrated Observer Framework Based Mechanical Parameters Identification for Adaptive Control of Permanent Magnet Synchronous Motor

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Complex System Modeling and Simulation 2022年第4期2卷 354-367页

作者： Zhong Liao Zhaohua Liu Lei Chen Mingyang Lyu Dian Wang Faming Wu Zhengheng Wang Hualiang Wei the School of Information and Electrical Engineering Hunan University of Science and TechnologyXiangtan 411201China the Wind Power Business Division CRRC Zhuzhou Institute Co.Ltd.Zhuzhou 412001China. the Department of Automatic Control and Systems Engineering University of SheffieldSheffieldS13JDUK.

An integrated observer framework based mechanical parameters identification approach for adaptive control of permanent magnet synchronous motors is proposed in this ***,an integrated observer framework is established for mechanical parameters’estimation,which consists of an extended sliding mode observer(ESMO)and a Luenberger *** at minimizing the influence of parameters coupling,the viscous friction and the moment of inertia are obtained by ESMO and the load torque is identified by Luenberger observer *** obtaining estimates of the mechanical parameters,the optimal proportional integral(PI)parameters of the speed-loop are determined according to third-order best design *** a result,the controller can adjust the PI parameters in real time according to the parameter changes to realize the adaptive control of the ***,the disturbance is compensated according to the ***,the experiments were carried out on simulation platform,and the experimental results validated the reliability of parameter identification and the efficiency of the adaptive control strategy presented in this paper.

关键词： parameter identification permanent magnet synchronous motor adaptive control extended sliding mode observer Luenberger observer

Charting the future:Intelligent and connected vehicles reshaping the bus system

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Journal of Intelligent and Connected Vehicles

Journal of Intelligent and Connected Vehicles 2023年第3期6卷 113-115页

作者： Kunjun Wang Ye Xiao Yixu He crrc Electric Vehicle Co. Ltd.Zhuzhou 412000China School of Information Engineering Chang’an UniversityXi’an 710064China

1 Introduction Driven by technological innovation and digital evolution,the current automotive industry is standing at the cusp of a transformative era(Liu et al.,2023).As urban centers continue to expand and intensify the demands on transportation networks,the need for solutions to alleviate congestion,boost traffic efficiency,and enhance road safety becomes increasingly *** this occasion,intelligent and connected vehicles,integrating vehicles,infrastructure,and cloud computing,promise a smarter mode of passenger transportation and pave the way for a more interconnected and responsive urban transit ecosystem(Cao et al.,2023).Therefore,traditional passenger buses are on the verge of significant transformation in terms of their functional technologies and operational *** will bring about a host of benefits such as higher efficiency,better passenger experiences,and safer road *** paper provides a comprehensive outlook on intelligent and connected passenger buses(ICPBs),delving into the integrated vehicle-road-cloud platform and highlighting the key technologies that will shape the future bus *** illustrated in Fig.1,it showcases the key perspectives on the future of ICPBs.

关键词： connected integrating system