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2011 International Conference on Advanced Power System Automation and Protection, APAP 2011

作者： Shi, Shenxing Wang, Jun Li, Aiming Du, Xinchun Cao, Xiaoxia Du, Yajun Dong, Xinzhou State Key Lab. of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian District Beijing 100084 China Yulin Power Company Shaanxi 719000 China China Jiuquan Satellite Launch Center Plumbing Electrical Station Jiuquan 732750 China

ISBN: (纸本)9781424496198

The paper proposes faulted feeder selector in power distribution system with neutral non-effectively grounded. At first, the paper presents basic principle of single-phase-to-ground fault feeder selection based on traveling waves, which compares amplitude and polarity of the initial current traveling waves in all feeders. Then the implementation scheme, including hardware design and software flowchart is presented. At last field application of faulted feeder selector is introduced. The field operation results validated the correctness of faulted feeder selector based on transient traveling wave. © 2011 IEEE.

关键词： Electric grounding

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Novel pre-distortion of power amplifier with proposed fractional order memory polynomial

Novel pre-distortion of power amplifier with proposed fracti...

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54th Annual IEEE Global Telecommunications Conference: "Energizing Global Communications", GLOBECOM 2011

作者： Ai, Bo Zhong, Zhang-Dui Jiang, Tao Li, Bo State Key Lab. of Rail Traffic Control and Safety Beijing Jiaotong University 100044 Beijing China Dept. of Electronic and Information HuaZhong Univ. of Sci. and Tech. 430074 Wuhan China Dept. of Electronic Engineering Xi'an University of Posts and Telecommunications 710121 Xi'an China

ISBN: (纸本)9781424492688

In this paper, we propose two novel schemes, which are based on our proposed novel fractional order memory polynomial pre-distorter, to conduct the digital base-band power amplifier pre-distortion with the improvement of power amplifier efficiency. For the first scheme, fractional order terms are included in the conventional memory polynomial containing the odd and even order polynomial terms. For the second scheme, it is to replace even order polynomial terms with fractional order polynomial terms to improve the linear performance of power amplifiers. The theoretical expressions for two schemes are derived. Both simulation results and numerical analysis show that more 11.0dB and 8.5dB out-of-band suppression gain could be obtained employing the proposed two schemes, respectively, which are compared with the conventional pre-distortion methods based on Wiener-Hammerstein and memory polynomial power amplifier models. Moreover, corresponding FPGA realization shows that the proposed two schemes are much cost-effective in terms of hardware resources and complexity of the implementation is low. © 2011 IEEE.

关键词： Power amplifiers

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Numerical simulation and model test study of mechanismof bolt in deep tunnel

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Yantu Lixue/Rock and Soil Mechanics 2011年第SUPPL. 1期32卷 719-724+786页

作者： Chen, Hao Ren, Wei-Zhong Li, Dan Xia, Bin-Wei State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China College of Urban Construction Wuhan University of Science and Technology Wuhan 430065 China Key Lab. for Exploitation of Southwestern Resources and Environmental Disaster Control Engineering Chongqing University Chongqing 400030 China

According to rock character of a certain soft rock tunnel of Chongqing, the model material is made from epoxy resin, polyamide, silicom rubber, firming agent of silicon rubber, quartz grit, powdery barite and gasoline. The physical model test of the unreinforced tunnel and bolt-reinforced tunnel are made in the true triaxial model test machine. By using strain measure technology, the strains of key parts of the surrounding rock and the bolt are measured;according to these data, the variability of the stress of surrounding rock and the variability of the axial force of the bolt are analyzed. The numerical simulation are made with the same boundary condition as the model test;according to these data, the plastic zone, stress field and the deformation of the surrounding rock are studied;the variation of the axial force of the bolt is studied. We compare the variation of stress of the surrounding rock and the variation of the axial force of the bolt of the model test with the numerical simulation and draw the conclusion that the two processes coincide with each other.

关键词： Numerical models

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2011 2nd International Conference on Mechanic Automation and control engineering, MACE 2011

作者： Li, Xiaoshuang Li, Yaoji Yin, Guangzhi He, Lin National Engineering Research Center of Phosphate Resources Development and Utilization Chongqing University Chongqing 400030 China State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam Chongqing University Chongqing 400030 China Key Lab. for the Rsrc. Exploitation and the Environ. Disaster Control Engineering in Southwest China State Ministry of Education Chongqing University Chongqing 400030 China Yunnan Phosphate Chemical Group Co. LTD. Jinning 650600 China

ISBN: (纸本)9781424494392

Based on the gently inclined medium thick phosphate rock of the deep part of the east mining section of +2150 level of Jinning-Six mine of Yunnan phosphate Co., Ltd, the similar material physical model simulation experiment of the stability of stope pillars under room and pillar mining was carried out by the mine pressure plane stress modeling experimental frame of college of resource and environmental sciences. Based on the experimental results,the deformation and failure changing law of the above roof, surrounding rock mass and stope pillar during the mining along the strike direction of phosphate were investigated. The experimental results showed: (1) With the increasing of the scope of mined-out area, the fwassure zone and separation layer zone of the roof in the original mined-out area of the stope were pressed compact step by step. And when the space range of the mined-out area reached some scale, the deformation of the fwassure zone and separation layer zone of the roof in the original mined-out drived to stabilwasation, and the sustain action of it to the gravity fore of the overlying strata was reexternalization. (2)After the mining, the subsidence region of the overlying strata of the stope mainly concentrated the roof and surrounding rock mass which beside the mined-out area, the position of the maximum subsidence point was in the center zone of the excavation space, with the increasing of the dwastance from the center of the stope along the trend and normal of the ore body, the subsidence value of the overlying strata of the stope was monotone decreasing. With the increasing of the region of the excavation space, the mining influence region and the mining inflence degree of the overlaying strata of the stope gradually increased. And the corresponding position of the maximum subsidence zone dynamically forward leaded, the final subsidence curve of the overlying strata was a bowl shaped curve. (3)The defoemation and failure characterwastics of the overlyin

关键词： Room and pillar mining

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2011 2nd International Conference on Mechanic Automation and control engineering, MACE 2011

ISBN: (纸本)9781424494392

Based on the gently inclined medium thick phosphate rock of the deep part of the east mining section of +2150 level of Jinning-Six mine of Yunnan phosphate Co., Ltd, the similar simulation model experiment of the stability of stope roof under cemented backfilling mining of waste rock was carried out by the mine pressure plane stress modeling experimental frame of college of resource and environmental sciences. Based on the experimental results, the stress changing law of the above roof of stope roof after the filling of stope along the strike direction of phosphate were investigated. Then the gently inclined medium thick phosphate rock of the deep part of the east mining section of Jinning-Six mine of Yunnan phosphate Co., Ltd could efficiently recover, and the surface in mining areas could also be protected. © 2011 IEEE.

关键词： Roofs

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Evaluation indexes of sand liquefaction analysed by rough set

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1st International Conference on Civil engineering, Architecture and Building Materials, CEABM 2011

作者： Liu, Nianping Wang, Hongtu Yuan, Zhigang Key Lab. for Exploitation of China Southwestern Resources and Environmental Disaster Control Eng. Chongqing University Ministry of Education Chongqing 400030 China State and Local Joint Engineering Laboratory of Methane Drainage in Complex Coal Gas Seam Chongqing University Chongqing 400030 China College of Environment and Resources Southwest University of Science and Technology Mianyang 621010 China

ISBN: (纸本)9783037851258

Sand liquefaction is a problem of complex evolution of the disaster, there is no accurate way to judge at present, this study put forward an analytical method to improve and optimize the evaluation system of sand liquefaction based on rough set. The significance of indexes are confirmed by calculating rough dependability between indexes and result for appraisement, the result show that SPT blow count has the greatest impact on the evaluation system, the groundwater level has greater impact, followed by the sand depth, epicenteral distance and duration. The proposed approach overcame the subjectivity of traditional weight determination method, so it is more objective and accurate, and it is reasonable and effective to optimize the evaluation index of sand liquefaction. © (2011) Trans Tech Publications.

关键词： Groundwater

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The research of synchronized phasor measurement units in smart substations

The research of synchronized phasor measurement units in sma...

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2011 International Conference on Advanced Power System Automation and Protection, APAP 2011

作者： Xu, Yong Zhang, Dao-Nong Yu, Yuehai Status Key Lab. of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian District Beijing 100084 China China Electric Power Research Institute Haidian District Beijing 100085 China North China Power Engineering Co. Ltd. Beijing 100120 China State Grid Electric Power Research Institute Nanjing 210061 China

ISBN: (纸本)9781424496198

Smart substation is the base of smart grid and it is made up of a lot of IEDs (intelligent electric device). Synchronized phasor measurement unit (PMU) plays a very important role in the smart grid, and a great deal of PMUs have been installed in China. The requirement of PMU in the smart substation is different from traditional substation. This paper introduces that the PMU is suitable for smart substation, there are several details that need to be complemented in IEC 61850 standards, and the paper gives some suggestion to improve it. © 2011 IEEE.

关键词： Phasor measurement units

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Multi-PID control of Hammerstein systems with input multiplicity

Multi-PID control of Hammerstein systems with input multipli...

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Chinese control Conference (CCC)

作者： Jingjing Du Xinliang Zhang Chunyue Song School of Electrical Engineering and Automation Henan Polytechnic University Jiaozuo P. R. China State Key Lab. of Industrial Control Technology Institute of Industrial Process Control Zhejiang University Hangzhou P. R. China

Hammerstein models are popular in describing nonlinear chemical processes. The general control strategy for Hammerstein models is the nonlinearity inversion method, which is unfortunately inapplicable to Hammerstein systems with input multiplicity. To overcome this difficulty, a Multi-PID control approach is proposed. Thus, a complex control problem is solved by a conventional and easy control strategy. A Heat Exchanger process is simulated to demonstrate the effectiveness of the Multi-PID control approach.

关键词： Process control Heating Steady-state Analytical models Predictive models Switches

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Time Synchronization in WSNs: A Maximum Value Based Consensus Approach

Time Synchronization in WSNs: A Maximum Value Based Consensu...

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IEEE Conference on Decision and control

作者： Jianping He Peng Cheng Ling Shi Jiming Chen State Key Lab. of Industrial Control Technology Zhejiang University Hangzhou 310027 China Department of Electric and Computer Engineering Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong

ISBN: (纸本)9781612848006

This paper proposes a novel synchronization algorithm for wireless sensor networks (WSNs), the Maximum Time Synchronization (MTS), which is based on maximum value consensus approach. The main idea is to maximize the local information to achieve a global synchronization. Compared with the existing consensus-based synchronization protocols, the main advantages of our protocol include: i) a faster convergence speed such that the synchronization can be completed in a finite time;ii) simultaneous compensation for both the skew and the offset. We provide a rigorous proof of convergence to global synchronization and also give the upper bound of the convergence time. Moreover, the protocol is completely distributed, asynchronous, and robust against packet losses, nodes failure and the addition of new nodes. Some numerical examples are presented to demonstrate the efficiency of our protocol.

关键词： clock recovery maximum value Converge local information. Skew Asynchronous

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Robust fractional order memory polynomial based pre-distorter

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IEICE Transactions on Communications 2011年第7期E94-B卷 1875-1882页

作者： Ai, Bo Zhong, Zhang-Dui Li, Bo Ma, Lin-Hua State Key Lab. of Rail Traffic Control and Safty Beijing Jiaotong University Beijing 100044 China Xi'an University of Posts and Telecommunications Xi'an City Shaanxi Province 710061 China Air Force Engineering University Xi'an City Shaanxi Province 710038 China

In this paper, a robust fractional order memory polynomial pre-distorter with two novel schemes to conduct digital base-band power amplifier pre-distortion is proposed. For the first scheme, fractional order terms are included in the conventional memory polynomial containing the odd and even order polynomial terms, which is called Scheme One. The second scheme, called Scheme Two, simply replaces even order polynomial terms with fractional order polynomial terms to improve the linear performance of power amplifiers. The mathematical expressions for these two schemes are derived. The computer simulations and numerical analysis show that, compared with the conventional pre-distortion methods, 11 dB and 8.5 dB more out-of-band suppression gain can be obtained by Scheme One and Scheme Two, respectively. Corresponding FPGA realization shows that the two schemes are cost-effective in terms of hardware resources. Copyright © 2011 The Institute of Electronics, Information and Communication Engineers.

关键词： Power amplifiers

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