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On adjacent-vertex-distinguishing total coloring of graphs

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Science china Mathematics 2005年第3期48卷 289-299页

作者： ZHANG Zhongfu, CHEN Xiang’en, LI Jingwen, YAO Bing, LU Xinzhong & WANG Jianfang college of Mathematics and information Science, Northwest Normal {2., lanzhou 730070, china Department of Computer, lanzhou Normal college, lanzhou 730070, china Institute of Applied Mathematics, lanzhou jiaotong university, lanzhou 730070, china {12., lanzhou jiaotong university, lanzhou 730070, china Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 100080, china 1. college of Mathematics and information Science Northwest Normal University 730070 Lanzhou China 2. Department of Computer Lanzhou Normal College 730070 Lanzhou China 3. Institute of Applied Mathematics Lanzhou Jiaotong University 730070 Lanzhou China 4. college of information and electrical engineering Lanzhou Jiaotong University 730070 Lanzhou China 5. Institute of Applied Mathematics Chinese Academy of Sciences 100080 Beijing China

In this paper, we present a new concept of the adjacent-vertex-distinguishing total coloring of graphs (briefly, AVDTC of graphs) and, meanwhile, have obtained the adjacent-vertex-distinguishing total chromatic number... 详细信息

关键词： graph, proper total coloring, adjacent-vertex-distinguishing total coloring, adjacent-vertex-distinguishing total chromatic number.

Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2. TANG Jun 2., ZHANG AiHua 3 & JIA Ya 2.1 Department of Physics, lanzhou university of Technology, lanzhou 730050, china 2.Department of Physics, Central china Normal university, Wuhan 430079, china 3 college of electrical and information engineering, lanzhou university of Technology, lanzhou 730050, china 1. Department of Physics Lanzhou University of Technology Lanzhou 730050 China2. Department of Physics Central China Normal University Wuhan 430079 China3. College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

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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.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.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

Optimal design study of high order FIR digital filters based on neural network algorithm

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Journal of Systems engineering and Electronics 2004年第2期15卷 115-119,130页

作者： Wang Xiaohua & He Yigangcollege of electrical and {2. engineering, Hunan university, Changsha 410082. P. R. china college of electrical and {2. engineering, Changsha university of Science and Technology,Changsha 410077, P. R. china college of electrical and {2. engineering Hunan University Changsha 410082 P. R. China college of electrical and {2. engineering Changsha University of Science and Technology Changsha 410077 P. R. China

An optimal design approach of high order FIR digital filter is developed based on the algorithm of neural networks with cosine basis function . The main idea is to minimize the sum of the square errors between the amplitude response of the desired FIR filter and that of the designed by training the weights of neural networks, then obtains the impulse response of FIR digital filter . The convergence theorem of the neural networks algorithm is presented and proved, and the optimal design method is introduced by designing four kinds of FIR digital filters , i.e., low-pass, high-pass, bandpass , and band-stop FIR digital filter. The results of the amplitude responses show that attenuation in stop-bands is more than 60 dB with no ripple and pulse existing in pass-bands, and cutoff frequency of passband and stop-band is easily controlled precisely .The presented optimal design approach of high order FIR digital filter is significantly effective.

关键词： high order FIR digital filters amplitude-frequency response neural network convergence theorem optimal design.

A linear ridgelet network approach for fault diagnosis of analog circuit

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Science china(information Sciences) 2010年第11期53卷 2251-2264页

作者： XIAO YingQun& HE YiGang college of electrical and {2. engineering, Hunan university, Changsha 410082. china 1. college of electrical and {2. engineering Hunan University Changsha 410082 China

A linear ridgelet network combining ridgelet, linear term and the standard feed-forward neural network used for diagnosing the faults of analog circuit is constructed, and a training algorithm based on the steepest gradient descent method and momentum method for this network and the procedure for diagnosing these faults are proposed. The resulting linear ridgelet network can learn more rapidly from training samples and handle more effectively the complicated fault information of circuit under test than wavelet network and ridgelet network, classifying these faults effeciently and correctly and achieving a high classification accuracy. The simulation results demonstrate the effectiveness of this approach.

关键词： fault diagnosis of analog circuit ridgelet linear ridgelet network wavelet packet decomposition

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 {2.,Ocean university of china,Qingdao 2.6100,china b college of information and electrical engineering,Shandong university of Science and Technology,Qingdao 2.6510,china c college of Automation and Electronic {2.,Qingdao university of Science and Technology,Qingdao 2.6042.china college of information Science and {2. 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

Improving TCP Performance over Wireless Links Using Link-Layer Retransmission and Explicit Loss Notification

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Journal of Systems engineering and Electronics 2002年第4期13卷 17-23页

作者： Zhou Zhizhao & Han Zhengzhi college of Electronic and information {2., Shanghai jiaotong university, Shanghai 2.0030, P. R. china college of Electronic and information {2. Shanghai Jiaotong University Shanghai 200030 P. R. China

In order to support the mobility of computers during communication, the transport control protocol (TCP) connections between fixed host and mobile host often traverse wired and wireless networks, and the recovery of the losses due to wireless transmission error is much different from congestion control. This paper analyzes the interaction between TCP and link layer retransmission scheme when the correlated packet are losses handled, indicates that a higher value of the maximum number of successive link layer timeout retransmissions has an adverse effect on TCP ability to perform congestion control rapidly. To achieve a better TCP performance, the paper proposes a strategy combining link-layer selective-reject automatic repeat request (ARQ) with explicit loss notification mechanism, which can respond to congestion quickly while keeping wireless link more reliable, and make TCP react to the different packet losses more suitably.

关键词： Congestion control (communication) Mechanisms Performance Transmissions

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 {2. 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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基于能量特征和神经网络的纹理图像分割

铁道学报 2004年第3期26卷 67-70页

作者：王喆王小鹏兰州交通大学信息与电气工程学院甘肃兰州730070

特征是描述纹理根本属性的一种有效手段,本文结合Gabor滤波器对不同频率和方向的选择特性及自组织特征映射神经网络对特征聚类的适应性和灵活性,提出了一种新的纹理图像分割方法。该方法首先通过Gabor滤波器提取纹理图像的能量特征,然... 详细信息

特征是描述纹理根本属性的一种有效手段,本文结合Gabor滤波器对不同频率和方向的选择特性及自组织特征映射神经网络对特征聚类的适应性和灵活性,提出了一种新的纹理图像分割方法。该方法首先通过Gabor滤波器提取纹理图像的能量特征,然后运用自组织特征映射神经网络进行特征聚类和分类,实现纹理图像的分割。仿真结果证明,该方法能有效地分割出区域特性不同的纹理,且错分率低于共生矩阵和K均值聚类相结合的分割方法。

关键词：纹理分割能量特征聚类自组织特征映射神经网络