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Web Information Extraction based on News Domain Ontology Theory

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Web Information Extraction based on News Domain Ontology The...

2.10 IEEE 2.d Symposium on Web Society

作者： Junfang Shi,LiLiu school of Information Engineering University of Science & Technology beijing,beijing,l 00083.{3.

＜正＞For the current web information extraction can’t adapt to the various page structures,this paper proposes a Web Information Extraction Method based on News Domain *** areas are accurately found out and the interested information was extracted exactly based on information extraction rules which is generated by news domain *** the technology of page processing,page conversion,XPath etc,the information extraction system based on news domain ontology is *** from news site shows that the approach proposed doesn ’t rely on the page structure and it can increase the recall and precision of information extraction.

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Theoretical progress in non-equilibrium grain-boundary segregation (Ⅰ): Thermally induced non-equilibrium grain-boundary segregation and intergranular embrittlement

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Science china(Technological sciences) 2009年第4期52卷 893-905页

作者： XU TingDong1, WANG Kai1 & SONG ShenHua2.1 Central Iron and Steel Research Institute, Superalloy Department, beijing 100081, china 2.Department of Materials Science and Engineering, Shenzhen Graduate {2., Harbin Institute of Technology, Shenzhen 518055, china

The research progress of non-equilibrium grain-boundary segregation theories in the last 2. years is reviewed. Based on studies by the present authors, the critical time of non-equilibrium segregation and its impact on the development of non-equilibrium segregation theories are described. Quasi- thermo- dynamics and kinetics for thermal non-equilibrium grain boundary segregation are detailed along with a non-equilibrium grain boundary cosegregation model. The experimental validation of the theories and their application to the reversible temper embrittlement of steels and the intermediate temperature brittleness in metals and alloys are also addressed.

关键词： grain-boundary segregation embrittlement

Correlation between neutron skin thickness and Rnp

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Correlation between neutron skin thickness and Rnp

第十三届全国核结构研讨会暨第九次全国“核结构与量子力学”专题讨论会

作者： X.Y.Sun~(1,2. D.Q.Fang~(1 1)) Y.G.Ma~(1 2.) X.Z.Cai~1 W.D.Tian~1 J.G.Chen~1 W.Guo~1 X.G.Cao~(1,2. Y.Fu~(1,2. P.Zhou~(1,2. G.Q.Zhang~(1,2. 1(Shanghai Institute of Applied Physics,Chinese academy of sciences,P.O.Box 800-2.4,Shanghai 2.1800,{2.) 2.Graduate school of Chinese academy of sciences,beijing 100039,{2.)

The correlation between neutron-to-proton yield ratio(R) and neutron skin thickness(δ) in neutron-rich projectile induced reactions is investigated within the framework of the Isospin-Dependent Quantum Molecular Dynamics（IQMD） *** adjusting the diffuseness parameter of neutron density in the Droplet model for the projectile,the relationship of the neutron skin thickness and the corresponding R in the collisions is *** simulate the reaction between Ca or Ni isotope with C at 50MeV/u,and the simulated data for Ca and Ni isotopes induced reactions show a good linear correlation between R andδ for neutron-rich *** is suggested that R could be used as an experimental observable to extract the neutron skin thickness for neutron-rich *** the neutron skin thickness of one isotope is obtained,we can get some information on the EOS in different theoretical models such as Skyrme Hartree-Fock,relativistic mean-field and BUU *** the isotope dependence of neutron skin thickness,a lot of information on the derivation of volume and surface symmetry energy,as well as nuclear incompressibility with respective to density can be *** is very important to the study of the EOS of asymmetric nuclear matter.

关键词： IQMD neutron skin thickness Rnp

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无线列控系统及无线传输系统失效性分析

铁道学报 2000年第1期22卷 62-66页

作者：钟章队廖敏北方交通大学电信学院北京100044

介绍了ＦＺＢ（新型无线列车控制）系统的系统结构，重点描述ＦＺＢ系统的无线传输系统ＧＳＭ－Ｒ的特点和在安全通信中的应用情况。在此基础上，对ＧＳＭ－Ｒ系统无线连接失效进行了详细的分析，包括失效影响、防护措施以及故障树分析。

关键词：无线通信铁路通信列车控制失效分析 FZB系统

Scattering of SH-Wave by Interface Co-line Cracks

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Scattering of SH-Wave by Interface Co-line Cracks

2.04安全科学与技术国际会议

作者： REN Yun-yan & HAN Feng ( school of Mechatronics Engineering beijing Institute of Technology beijing 100081 {3.)

In this paper, the scattering of SH-wave by interface multiple co-line cracks is studied with Greens function. In order to solve the problem, by ways of the cutting, a suitable scattering-model is con

关键词： Green function scattering of SH-wave integral equation dynamic stress intensity factor(DSIF)

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电弧喷射推力器化学非平衡数值模拟

推进技术 2004年第5期25卷 458-462页

作者：肖应超汤海滨北京航空航天大学宇航学院北京100083

为了准确把握电弧喷射推力器工作过程物理机理与特征,采用化学非平衡模型对不同压缩室直径下低功率氮电弧喷射推力器工作情况进行了数值模拟。模型考虑了工作过程中的分解反应、电离反应和复合反应,化学动力学模型为4组分,4反应的有限... 详细信息

为了准确把握电弧喷射推力器工作过程物理机理与特征,采用化学非平衡模型对不同压缩室直径下低功率氮电弧喷射推力器工作情况进行了数值模拟。模型考虑了工作过程中的分解反应、电离反应和复合反应,化学动力学模型为4组分,4反应的有限速率化学反应模型。采用二阶精度NND格式数值求解耦合电磁源项和化学反应源项的N S方程组,采用有限控制容积积分方法求解由麦克斯韦方程组推导出的电磁场方程。数值模拟的结果揭示了推力器内部电弧能量输入作用和高温电离气体的离解电离状况,给出了不同压缩室直径下推力器的推力、比冲和推进效率。结果分析表明,压缩室直径对推力器性能具有较大影响。

关键词：电弧喷射推进推力器化学非平衡模型数值仿真流动分布

WHOLE PROCESS ANALYSIS OF PRE-STRESSED T-SHAPED REACTIVE POWDER CONCRETE BEAMS

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WHOLE PROCESS ANALYSIS OF PRE-STRESSED T-SHAPED REACTIVE POW...

The International Symposium on Innovation & Sustainability of Structures in Civil Engineering

作者： Caihong Liu and Ri Gao school of Civil Engineering and Architecture beijing Jiaotong University beijing 100044 {3.

＜正＞Reactive powder concrete （RPC） is a new type of concrete with ultra-high mechanical properties. Constructional members made by RPC differ greatly from those by conventional concrete in its deformation and failure under loading. Using nonlinear finite element method, it is mainly analyzed in this paper that the shear failure process of prestressed T-shaped RPC beam under mid-span load from the time when the initial crack comes to appear to the time when the beam comes to fail, including the course of crack’ s gradual *** results obtained from the analysis accord well with those obtained from the experiment.

关键词： T-shaped beam reactive powder concrete (RFC) nonlinear finite element.

An UWB Receiver Structure with Improved Performance in Timing Jitter Sensitivity

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An UWB Receiver Structure with Improved Performance in Timin...

2.09 3.d IEEE International Symposium on Microwave,Antenna,Propagation and EMC Technologies for Wireless Communications

作者： ZHANG Bing LI Baoxue FEI Yuanchun school of Information and Electronics beijing Institute of Technology beijing {3.

UWB system is very sensitive to timing jitter due to the extremely small width and low duty-cycle of the pulses it employs. The presence of timing jitter can markedly degrade the system throughput, BER performance and multiple-access performance, and even can disable the correlation receiver in severe condition. So, available measures should be taken to reduce the effects caused by timing jitter. In this paper, a method of combating timing jitter by introducing additional modification to the conventional local template which is used to correlate with the received waveform is presented, and the mathematical formula of the additional modification corresponding to normal distribution of timing jitter are derived. Furthermore, an UWB receiver structure based on this method is proposed, and then the receiver performance is evaluated in terms of BER in presence of timing jitter. The result shows that the proposed receiver structure outperforms the conventional receiver structure in BER performance, especially for the large amount of timing jitter.

关键词： UWB receiver correlation timing jitter additional modification BER performance

基于Multi-Agent的列车速度联控系统的仿真研究

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系统仿真学报 2004年第12期16卷 2647-2650,2654页

作者：乐逸祥周磊山北京交通大学交通运输学院北京100044

以列车速度联控行车制式为基础,采用Multi-Agent技术设计了列车速度联控仿真系统的结构和运行控制模型,并完成了软件的设计和开发。使用该仿真系统进行了多个运输方案的试验,结果表明,基于Multi-Agent技术设计和开发的系统能较好地满足... 详细信息

以列车速度联控行车制式为基础,采用Multi-Agent技术设计了列车速度联控仿真系统的结构和运行控制模型,并完成了软件的设计和开发。使用该仿真系统进行了多个运输方案的试验,结果表明,基于Multi-Agent技术设计和开发的系统能较好地满足仿真的需求,同时该系统也为验证和分析速度联控行车制式理论的特点提供了一个研究平台。

关键词： Multi-Agent 速度联控人工智能行车组织仿真