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Isotope shift calculations for D lines of stable and short-lived lithium nuclei

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Chinese Physics B 2016年第11期25卷 194-198页

作者：余庚华赵朋义徐炳明杨维朱晓玲 school of information Science and engineering Chengdu University College of Physics and Electronic Science Hubei Normal University school of information Science and engineering Ocean University of China

The isotope shifts（TSs） for the 2s2S（1/2） to 2p2PJ（J = 1/2,3/2） transitions of the lithium nuclei including the stable and short-lived isotopes are calculated based on the multi-configuration Dirac-Hartree-Fock method and the relativistic configuration interaction *** results are in good agreement with the previous theoretical and experimental results within a deviation less than 0.05%.The methods used here could be applied to the IS calculations for other heavier Li-like ions and few-electron systems.

关键词： nuclei lithium isotopes relativistic Hartree lived transitions Dirac deviation nucleus

STABILITY ANALYSIS OF DECENTRALIZED ADAPTIVE BACKSTEPPING CONTROL SYSTEMS WITH ACTUATOR FAILURES

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Journal of Systems Science & Complexity 2009年第1期22卷 109-121页

作者： Wei WANG Changyun WEN Guanghong YANG school of electrical and Electronic engineering Nanyang Technological University Nanyang 639798 Singapore. College of information Science and engineering Northeastern University Shenyang 110004 China.

In this paper,the authors analyze the stability of a class of interconnected systems withsubsystem unmodeled dynamics and dynamic interactions employing decentralized adaptive controllersdesigned by Wen,Zhou,and Wang (2008) in the presence of actuator *** will be shown that theglobal stability of the remaining closed-loop system is still ensured and the outputs are also regulatedto zero when some subsystems break down.

关键词： Actuator failure adaptive control backstepping decentralized control stability analysis

Research on arc erosion of silver-based alloy contact materials under low voltage,resistive load and small current at 400 Hz and 50 Hz

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Journal of Pharmaceutical Analysis 2009年第3期21卷 149-154页

作者： Jing Li1,2,Zhi-ying Ma11. school of electrical engineering,Xi’an Jiaotong university,Xi’an 710049 2. school of electrical information,Hunan Institute of engineering,Xiangtan 411101,china. school of electrical engineering Xi'an Jiaotong University Xi'an 710049 China school of electrical information Hunan Institute of Engineering Xiangtan 411101 China

By using a self-developed IF power and a ASTM contact material experimental system of small-capacity and variable frequency,the value of arcing characteristics and the welding force of the silver-based contact material are acquired under low voltage,resistive load and small current at 400 Hz and 50 Hz. By means of an electricity-ray analytical balance,SEM and EDAX,the weighing values of the contact materials and the changes of AgCdO,AgNi,AgC and AgW contact material surface profile and micro-area constituent are obtained and analyzed. The arc erosion causes of silver-based alloy contact materials at 400 Hz and 50 Hz are also discussed.

关键词： silver-based alloy low voltage 400 Hz 50 Hz contact material arc erosion

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牵引变压器绕组变形在线检测方法研究

铁道学报 2004年第2期26卷 60-65页

作者：高仕斌王果西南交通大学电气工程学院四川成都610031

国内外的研究和统计表明,变压器绕组变形是电力系统安全运行的一大隐患,通过测量变压器绕组短路电抗来判断变压器绕组是否变形是一种有效的方法。本文提出了2种通过在线监测原、次边的电压和电流,实时计算绕组的短路电抗来判断变压器绕... 详细信息

国内外的研究和统计表明,变压器绕组变形是电力系统安全运行的一大隐患,通过测量变压器绕组短路电抗来判断变压器绕组是否变形是一种有效的方法。本文提出了2种通过在线监测原、次边的电压和电流,实时计算绕组的短路电抗来判断变压器绕组变形的方法,并对电气化铁路主要接线形式的牵引变压器绕组变形的在线监测方案进行了设计。论文分析了互感器误差对短路电抗测量结果的影响;通过变压器建模,分析了磁滞特性和负载变化大小对短路电抗测量结果的影响,验证了该方法在工程应用上的可行性。

关键词：变压器绕组变形短路电抗在线监测

基于神经网络和模糊理论的电力系统动态安全评估

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四川大学学报（工程科学版） 2004年第1期36卷 106-110页

作者：严宇刘天琪四川大学电气信息学院四川成都610065

在实用动态安全域的基础上提出了实用动态安全域的神经网络和模糊理论方法,构建了用于拟合动态安全域的ANN拟和器和用模糊理论在安全边界上构造一个模糊中间带的模糊识别器,并对该方法中的系统灵敏度和超平面度进行了分析。最后对4机11... 详细信息

在实用动态安全域的基础上提出了实用动态安全域的神经网络和模糊理论方法,构建了用于拟合动态安全域的ANN拟和器和用模糊理论在安全边界上构造一个模糊中间带的模糊识别器,并对该方法中的系统灵敏度和超平面度进行了分析。最后对4机11节点测试系统进行了仿真计算。实验表明,用神经网络拟合的动态安全域其拟和合度和精度均高于传统最小二乘法的拟合,其模糊识别器进一步减少了临界点的误判和在安全域边界上稳定和非稳定点的误判。

关键词：电力系统动态安全评估动态安全域神经网络模糊理论模糊识别器

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基于变电所自动化系统的互感器断线检测

铁道学报 2002年第2期24卷 39-43页

作者：高仕斌西南交通大学电气工程学院四川成都610031

牵引变电所电压、电流互感器时常发生断线故障 ,直接影响继电保护的正确动作和测量表计的正常指示 ,危及牵引供电系统的安全运行。由于牵引供电系统的特殊性 ,电力系统相对成熟的检测方法在牵引供电系统可能不适用 ,本文基于牵引变电所... 详细信息

牵引变电所电压、电流互感器时常发生断线故障 ,直接影响继电保护的正确动作和测量表计的正常指示 ,危及牵引供电系统的安全运行。由于牵引供电系统的特殊性 ,电力系统相对成熟的检测方法在牵引供电系统可能不适用 ,本文基于牵引变电所综合自动化系统的硬件平台和冗余信息 ,提出了在变电所监控主机或调度端实现的电压。

关键词：电压互感器电流互感器断线故障牵引变电所综合自动化系统检测

Characteristic analysis of unsteady viscous flow around a cavitating propeller

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Science china(Technological Sciences) 2010年第7期53卷 1983-1992页

作者： ZHU ZhiFeng1, 2, FANG ShiLang1 & WANG XiaoYan1 1 Key Laboratory of Underwater Acoustic Signal Processing of Ministry of Education, Southeast university, Nanjing 210096, china 2 school of electrical engineering and information, Anhui university of Technology, Maanshan 243002, china Key Laboratory of Underwater Acoustic Signal Processing of Ministry of Education Southeast University Nanjing China school of electrical engineering and information Anhui University of Technology Maanshan China

Based on viscous multiphase flow theory, this paper presents some recent validation results with a hybrid grid and sliding mesh solving Unsteady Navier-Stokes (N-S) and Bubble Dynamics equations as applied to prediction of pressure, velocity and vapor volume fraction in the wake in an uniform inflow. Comparable to experimental results, numerical predictions of sheet cavitation, tip vortex cavitation and hub vortex cavitation are in agreement with the corresponding experimental data, the same as numerical predictions of pressure in wake. Tip vortex cavitation is the most important to generate the pressure fluctuation within the near wake. The characteristics such as blade and shaft rate frequency of propeller pressure in wake coincide with its geometric model and parameters. With increasing distance from propeller disk, the pressure signals at blade frequency de-crease. The process of attenuation becomes fast with the decreased advance coefficient and cavitation number.

关键词： cavitating flow RANS propeller sliding mesh multiphase flow

COMPLEXITY ANALYSIS OF NETWORK-BASED DYNAMICAL SYSTEMS

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Journal of Systems Science & Complexity 2011年第3期24卷 413-432页

作者： Guofeng ZHANG Long WANG Tongwen CHEN school of Electronic engineering University of Electronic Science and Technology of China Chengdu 610054 China. Intelligent Control Laboratory Center for Systems and Control College of Engineering Peking University Beijing 100871 China Department of electrical and Computer engineering University of Alberta Edmonton Alberta T6G 2V4 Canada

This paper investigates the nonlinear dynamics of network-based dynamical systems where network communication channels of finite data rates are inserted into the closed loops of the control systems. The authors analyze the bifurcation and chaotic behavior of the non-smooth dynamical systems. The authors first prove that for almost all system parameters there are no periodic orbits. This result distinguishes this type of non-smooth dynamical systems from many others exhibiting border-collision bifurcations. Next, the authors show analytically that the chaotic sets are separated from the region containing the line segment of all fixed points with a finite distance. Finally, the authors employ a simple model to highlight that both the number of clients sharing a common network channel and fluctuations in the available network bandwidth have significant influence on the performance of such dynamical systems.

关键词： Bifurcation feedback network-based dynamical system non-convexity periodicity.

Multi-channel radar array design method and algorithm

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Science china(information Sciences) 2010年第7期53卷 1470-1480页

作者： SU Yi1*, ZHU YuTao1, YU WenXian2, XU HongBo1 & LEI WenTai1 1school of Electronic Science and engineering, National university of Defense Technology, Changsha 410073, china 2school of Electric, information and electrical engineering, Shanghai Jiao Tong university, Shanghai 200240, china school of Electronic Science and engineering National University of Defense Technology Changsha China school of Electric Information and Electrical Engineering Shanghai Jiao Tong University Shanghai China

The array design of radar antenna is no more a new problem at all. Nevertheless, the array design of multi-channel radar, especially that of MIMO (multiple-input multiple-output) radar, is a new problem. The performance of space diversion and spatial sampling of target scattering are dependent on the array design of MIMO radar, and consequently, which in turn will determine the performances of target parameter estimation, DOA, and imaging. In this paper, commencing with target scattering model, T/R signal model of MIMO radar, and spatial sampling ability for this system are analyzed. Conceptually, under the far field condition, spatial convolution principle determines the array design theory. Based on this idea, array design method and also algorithm are proposed in this paper.

关键词： MIMO-radar antenna arrays DOA estimation spatial sampling imaging algorithm