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Three-level NPC Inverter with IGCT for High Power AC Drives

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Three-level NPC Inverter with IGCT for High Power AC Drives

Analysis and Forecast for Timber Supply and Demand in china

11th International Conference on Electrical Machines and systems

作者： Shutian Zhang~1 Qiongxuan~1 Ge Yaohua Li 1 Institute of Electrical Engineering chinese academy of sciences beijing P.R.china

＜正＞Ⅰ.INTRODUCTION Recently,Three-level NPC inverters have been widely used for high power AC *** Integrated Gate-Commutated Thyristor（IGCT）is a new power *** several years of its introduction,the IGCT has established itself as power device of choice at MW levels by offering reliability and efficiency and the high power densities. This paper presents a high power Three-level NPC inverter with IGCT devices and its control for variable frequency AC drives.A new switching sequence method is proposed to overcome minimum-on-pulsewidth and eliminate even-order harmonic.

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chinese Forestry science and Technology 2011年第4期10卷 36-40页

作者： TAN Xiufeng Research Institute of Forestry Policy and Information, chinese academy of Forestry, beijing100091, P.R.china

Based on the data from 2002 to 2010, the paper analyzed the situation of timber supply and demand in china, and concluded that supply-demand could be balanced basically if taking accounting of timber import. Based on the data from the Seventh National Forestry Inventory, the potential of providing timber from natural forest and plantation was analyzed. The paper also forecasted the future features and trend of timber supply and demand in china. In the end, strategic measures and technological and policy guarantee system were put forward.

关键词： timber supply demand china

Microbial Fuel Cells with the Addition of Vanadyl Compounds for Performance Improvement

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Microbial Fuel Cells with the Addition of Vanadyl Compounds ...

A CRYPTOGRAPHIC STUDY ON S-BOXES OF DES TYPE Ⅲ

The 4th Joint china/Japan Chemical Engineering Symposium

作者： DU Zhuweia LI Qinghaib TONG Menga LI Dingjiea LI Shaohuaa LI Haorana **aNational Key Laboratory of Biochemical Engineering Institute of Process Engineering chinese academy of sciences beijing 100080 chinabKey laboratory for Thermal science and Power Engineering of Ministry of Education Tsinghua University beijing 100084 china

A microbial fuel cell was constructed with Rhodoferax ferrireducens, and effects of NaVO3 inanode chamber and cathodic eletron acceptor K3[VO（O2）2（OOC-COO）] （abbr. KVC） were studied in thepresent work. The highest current output of the MFC was 0.581mA, which was 0.272mA higher than that ofthe control experiment, with the addition of NaVO3 at the concentration of 4mmol/L in the anode chamberand the external resistance of 510?. KVC in the cathodic compartment also improved the performance of theMFC. The highest current of 0.949mA could be achieved at the KVC concentration of 25mmol/L. Thecurrent of the MFC was further enhanced to 1.06 mA whilst the NaVO3 catalyst and KVC catalyst wereadded to the anodic and cathodic compartments, respectively.

关键词： glucose Rhodoferax ferrireducens vanadium microbial fuel cell

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systems science and Mathematical sciences 1992年第1期5卷 27-32页

作者： YANG Junhui (Computing Center of Academia Sinica,beijing 100080,china)DAI Zongduo ZENG Kencheng (Graduate School of Academia Sinica,beijing 100039,china)

The so-called selected permutations on the set of the first 16 non-negative integers are classified under the action of a certain motion ***-base consisted of the class representatives has been provided.

关键词： DES S-box

The influence of discourse hierarchy on the acoustic manifestation of focus in standard chinese

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chinese Journal of Acoustics 2011年第4期30卷 437-452页

作者： ZHAO Jianjun YANG Xiaohong YANG Yufang LU Shinan State Key Laboratory of Brain and Cognitive science Institute of Psychology Chinese Academy of Sciences Beijing 100101 Graduate University of chinese academy of sciences beijing 100039 Institute of Acoustics Chinese Academic of Sciences Beijing 100190

A phonetic experiment was conducted to investigate whether the acoustic features of discourse focus were subjected to the influence of discourse hierarchy. Six speakers were instructed to read aloud 32 groups of experimental material. The duration, pitch range, f0 maxima, and f0 minima of foci in different discourse hierarchies were extracted for statistical analysis. The results revealed that foci embedded higher in the discourse hierarchy had relatively longer duration and more expanded pitch range; moreover, with the variation of tone combination, foci in different discourse hierarchies differed remarkably in their manifestation of f0 maxima and f0 minima features. Specifically speaking, for non-low tone combinations, foci in higher discourse hierarchy were pronounced with higher f0 maxima, while for low-tone combinations, foci in higher discourse hierarchy were articulated with lower f0 minima.

关键词：声学特性话语中国标准实验材料提取时间层次结构拼音文字统计分析

Research of Microglia BV-2 Activation Mechanism

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Research of Microglia BV-2 Activation Mechanism

RRM:An incentive reputation model for promoting good behaviors in distributed systems

The 1st International Symposium on Brain Function and Disorders（SBFD）

作者： QIANG Min,HE Rong-Qiao~* State Key Lab of Brain and Cognitive science,Institute of Biophysics,chinese academy of sciences,15 Da Tun Road,Chao Yang District,beijing,100101,china

Microglia are the major immune cells of central nervous system(CNS),which play an important role in the process of host resisting to exogenous micro-organisms and *** ischemia of brain tissue or damage to CNS,microglia become activated to protect *** increasing number of studies have found that in Alzheimer’s disease(AD) and other neurodegenerative diseases,long-term persistent activation of microglia could cause

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science in china(Series F) 2008年第11期51卷 1871-1882页

作者： ZHANG Hong1,2,DUAN HaiXin1,3 & LIU Wu1,3 1 Tsinghua National Laboratory for Information science and Technology,Tsinghua University,beijing 100084,china 2 Department of Computer science and Technology,Tsinghua University,beijing 100084,china 3 Network Research Center,Tsinghua University,beijing 100084,china Tsinghua National Laboratory for Information science and Technology Tsinghua University Beijing China Department of Computer science and Technology Tsinghua University Beijing China Network Research Center Tsinghua University Beijing China

Reputation systems represent soft security mechanisms that complement traditional information security mechanisms. They are now widely used in online e-commerce markets and communities in order to stimulate good behaviors as well as to restrain adverse behaviors. This paper analyzes the limitations of the conversational reputation models and proposes an incentive reputation model called the resilient reputation model （RRM） for the distributed reputation systems. The objective of this reputation model is not only to encourage the users to provide good services and, therefore, to maximize the probability of good transaction outcomes, but also to punish those adverse users who are trying to manipulate the application systems. The simulation results indicate that the proposed reputation model （RRM） could effectively resist against the common adverse behaviors, while protecting the profits of sincere users from being blemished by those adversaries.

关键词： reputation model distributed system trust soft security