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Preparation and characterization of PZT thick film enhanced by ZnO nanowhiskers for MEMS piezoelectric generators

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Progress in Natural Science:Materials International 2011年第02期21卷 159-163页

作者： Zhong-xia DUAN~1,Guo-qin YU~2,Jun-biao LIU~1,Jun LIU~2,Xiao-wen DONG~2,Li HAN~1,Peng-yun JIN~1 1.Institute of electrical engineering,Chinese Academy of Sciences,Beijing 100190,china 2.shanghai Municipal electric power Company,shanghai 200025,china [a] Institute of electrical engineering Chinese Academy of Sciences Beijing 100190 China [b] shanghai Municipal electric power Company Shanghai 200025 China

A hybrid sol-gel route which was used to fabricate PZT thick film for MEMS piezoelectric generators was investigated. （100）-oriented Pb(Zr0.52Ti0.48)O3thick films enhanced by ZnO nanowhiskers（ZnOw） were successfully prepared on Pt/Cr/SiO2/Si substrates via spin-coating ZnOwsuspension and PZT *** influences of film thickness on the microstructure and electrical properties of composite thick film were *** results show that PZT composite thick films have（100）-oriented perovskite *** results show that,the surface of as-prepared（100）-oriented PZT piezoelectric composite thick film is smooth,compact and crack-free,and the cross section is *** composite thick films exhibit good ferroelectric,dielectric and piezoelectric properties.2 urn-thick（100）-oriented PZT piezoelectric composite thick film has the remnant polarization intensity and coercive field of 6.7μC/cm2and 92.5 kV/cm,the dielectric constant and dielectric dissipation of 1 431 and 0.44,respectively,and piezoelectric constant d33is calculated to be 151.0 pC/*** composite thick film is good to meet the use of MEMS piezoelectric generators.

关键词： PZT thick film ZnO nanowhisker electrical properties piezoelectric generator

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 1. School of Electronic Science and engineering National University of Defense Technology Changsha 410073 China2. School of Electric Information and Electrical Engineering Shanghai Jiao Tong University Shanghai 200240 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

High-temperature tribological properties of Ni-P alloy coatings deposited by electro-brush plating

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Rare Metals 2011年第6期30卷 669-675页

作者： LI Zhiming QIAN Shiqiang WANG Wei SHEN Hongwei LONG Hesun College of Material engineering Shanghai University of Engineering Science Shanghai 201620 China shanghai electric power Generatzon Equtpment Co. Ltd. Turbine Works Shanghai 200240 China

High-temperature tribological properties of Ni-P alloy coatings processed by electro-brush plating on 20CrMo steel have been investigated. A baU-on-disc configuration was employed and 4 mm diameter Si3N4 balls were used as static counterpart. All the wear tests were carried out at 450℃ for 180 rain without lubricants. The electro-brush plating Ni-P coating is amorphous in as-deposited condition, and it becomes polycrystalline with the formation of Ni and Ni3P after heat treatment at 450℃for 1 h. The friction coefficient of the Ni-P coating is just 50% of that of the 20CrMo steel at the friction temperature of 450℃. A mild adhesive wear mechanism was found for the electro-brush plating Ni-P coating tested at 450℃, whereas for the 20CrMo steel at the same temperature a mixed adhesive and abrasive wear mechanism was observed.

关键词： sliding wear high temperature electro-brush plating Ni-P alloy coating surface analysis

A novel control scheme of 230kA DC power source using thyristor, Phase-shifting rectifier transformer and On-load tap changer

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A novel control scheme of 230kA DC power source using thyris...

State Inspection for Transmission Lines Based on Independent Component Analysis

CES/IEEE 5th International power Electronics and Motion Control Conference

作者： Qiao Shutong Jiang Jianguo Member IEEE Zuo Dongsheng and Wu Xiaojie department of electrical engineering shanghai Jiao Tong university shanghai 200240 china china university of Mining and Technology Xuzhou Jiangsu 221008 china department of electrical engineering Shanghai Jiaotong University Shanghai China china university of Mining and Technology Xuzhou Jiangsu China

ISBN: (纸本)1424404487;9781424404483

＜正＞This 230kA DC power source is composed of four set separated DC power in parallel operation. There are +3.75°,-3.75°, +11.25°, -11.25° phase shifting between each rectifier transformer and original source. Each set device mainly contains on-load tap changer, phase-shifting rectifier transformer and con-phase counter parallel rectifier. In this paper, a current control scheme is realized based on SIEMENS corp. product. According to the required function, the hardware is chose and described, and the software is designed and realized. The design control system is organized by current control level, logic control level and human level. The relation between these levels is determined. The system is validated by electrolytic aluminum plant. From the measured data, the current control precision can reach 0.1% in dynamic process. The rectifier efficiency is more than 97.5%. The whole control device’s realized zero current changing on-load tap changer. This developed DC power source can utilize for electrochemical, electro winning, plasma torches etc.

关键词： power source phase-shifting rectifier transformer Control system Parallel operation

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Journal of shanghai Jiaotong university(Science) 2009年第2期14卷 129-132页

作者：任丽佳江秀臣盛戈嗥杨巍巍 department of electrical engineering Shanghai Jiaotong University Urban power Supply Company Shanghai Municipal Electric Power Company Northeast china Grid

Monitoring transmission towers is of great importance to prevent severe thefts on them and ensure the reliability and safety of the power grid *** component analysis(ICA) is a method for finding underlying factors or components from multivariate statistical data based on dimension reduction methods,and it is applicable to extract the non-stationary *** based on negentropy is presented to effectively extract and separate the vibration signals caused by human activity in this paper.A new method combined empirical mode decomposition(EMD) technique with the adaptive threshold method is applied to extract the vibration pulses,and suppress the interference *** practical tests demonstrate that the method proposed in the paper is effective in separating and extracting the vibration signals.

关键词： state inspection transmission lines independent component analysis (ICA) negentropy adaptive threshold empirical mode decomposition (EMD)

Current distribution and stability of LTS/HTS hybrid superconducting conductors

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Science china(Technological Sciences) 2010年第7期53卷 2000-2007页

作者： GUAN XiaoJin1,2, WANG YinShun1 & ZHOU WeiWei3 1 Key Laboratory of HV and EMC Beijing, North china electric power university, Beijing 102206, china 2 department of Physics, Baoding university, Baoding 071000, china 3 Institute of electrical engineering, Chinese Academy of Sciences, Beijing 100190, china 1. Key Laboratory of HV and EMC Beijing North China Electric Power University Beijing 102206 China2. Department of Physics Baoding University Baoding 071000 China3. Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China

Current distribution and stability of a hybrid LTS/HTS superconductor, consisting of multifilamentary NbTi/Cu and Bi2223/Ag tapes, were numerically analyzed according to power-law models. The results showed that most of current passed through the LTS and the current increased in the HTS with temperature rise when the transport current was below the critical current of the hybrid conductor. The quench propagation velocity of the hybrid conductor was smaller but its minimum quench energy was larger than those of LTS conductors, indicating that the stability of the hybrid superconducting conductor was effectively improved and a high engineering current density was simultaneously achieved. Finally, a hybrid sample, made by soldering Bi2223/Ag tape onto NbTi/Cu conductor, was prepared and tested successfully at helium temperature. The experimental results qualitatively agreed with the simulated ones.

关键词： distribution hybrid conductor minimum quench energy quench propagation velocity n value stability

The Application and Research in the Digital Substations System Based on IEEE 1588

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The Application and Research in the Digital Substations Syst...

Risk Bound of Priority Ordered Neural Network With Multi-Weighted Neurons

2010 2nd International Conference on Multimedia and Computational Intelligence (ICMCI 2010)

作者： YU Huiqun College of electric power and Automation engineering shanghai university of electric power shanghai 200090 china

Increasingly high level of synchronization is required in the digital automation of *** on IEC61850 standard,this paper presents the IEEE 1588 clock protocol and its fundamental *** article points out the particularity of time synchronization with high accuracy through the comparison with an extensively-used network time *** exact time synchronization strategy conforming to IEEE 1588 protocol,which can be used for data sampling in digital substation,is also explored.

关键词： Digital Substation IEC61850 IEEE 1588 Clock Synchronization

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Risk Bound of Priority Ordered Neural Network With Multi-Wei...

Spatially discontinuous ionization phenomenon in inhomogeneous soil

2011 IEEE International Conference on Computer Science and Automation engineering(CSAE 2011)

作者： Shi-jiao ZHU School of Computer and Information engineering shanghai university of electric power shanghai 200090 china Jun YANG School of Computer and Information engineering shanghai university of electric power shanghai 200090 china

neural networks are widely used in different ***,fixed architecture is difficult to use in practice for its pre-determined neurons and *** architecture is proposed in this paper for neural network based on idea of human’s cognition where each neuron has its own priority number and evolution of learning process with *** prediction theory,risk bound of the architecture with multi-weighted neurons are *** results show that the propose method outperforms the SVM method using limited *** proposed method is constructive and this work can provide a very useful method for neural network learning model.

关键词： Neural Network Risk bound MultiWeighted

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Science china(Technological Sciences) 2010年第4期53卷 918-921页

作者： ZHANG BaoPing,HE JinLiang & ZENG Rong State Key Lab of power Systems,department of electrical engineering,Tsinghua university,Beijing 100084,china 1. State Key Lab of power Systems Department of Electrical Engineering Tsinghua University Beijing 100084 China

By using X-ray film imaging technology,a phenomenon of discontinuous ionization was observed in the inhomogeneous soil around the grounding electrode on which a surge voltage was applied.A simplified two-phase solid-gas model was built to study the electric field distribution in the soil to explain the discontinuous ionization *** showed the differences of the dielectric properties,the shapes and sizes of soil particles can cause discontinuous ionization in the soil.

关键词： discontinuous ionization inhomogeneous soil X-ray film porous medium electric field distribution