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Modal Analysis of Thread off Failure of Oil Round Thread Casing Connection

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Journal of university of Science and Technology beijing 2001年第4期8卷 277-279页

作者： LiWang, Yong Zang, Zhaoneng Chen, Dechun Tong, Jiaxiang Zou 1) Shanahai jiaotong university Shanghai 200030 china 2) Mechanical Engineering school. university of Science and Technology beijing. beijing 100083. china Shanghai jiaotong university Shanghai 200030 China Mechanical Engineering school University of Science and Technology Beijing Beijing 100083 China

The dynamic modal model analysis of the oil casing connection is done by finite element method (FEM), and the first nature frequency, the second nature frequency, the vibration mode shape and the time domain of the node displacement and the element stress variation in the thread connection are gotten. The *** stresses of the connection in the static and dynamic state are also studied. The results of calculation and analysis show: (1) because the maximum of static stress is at the coupling thread end of connection, the connection begins to thread off at the coupling thread end, which is in accord with the results of the thread off experiment in laboratory; (2) because the first nature frequency is very high, the probability of casing connection to be damaged from vibration is little; (3) the shock dynamic load makes casing connection begin to thread off at the tube thread end.

关键词： API round thread casing connection modal analysis

Quantitative Analysis of Impact of Education on Improving Farmers′ Net Income and Yield Per Capita

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Systems Science and Systems Engineering 2002年第1期11卷 90-94页

作者： DING Jing-zhi Northern jiaotong university, beijing 100044, china Northern jiaotong university Beijing 100044 China

In this paper, we analyze the relation between farmers′ schooling and their net income and yield per capita by systemic and scientific method, concluding that improving farmers′ educational level may increase their ... 详细信息

关键词： education net income yield cash income

Progress in the development of therapeutic antibodies targeting prion proteins and β-amyloid peptides

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Science china(Life Sciences) 2010年第8期53卷 959-963页

作者： HE JinSheng1, ZHANG Ying1 & HONG Tao1,2 1College of Life Sciences and Bioengineering, school of Science, beijing jiaotong university, beijing 100044, china 2Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, beijing 100052, china College of Life Sciences and Bioengineering School of Science Beijing Jiaotong University Beijing China Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Beijing China

Prion diseases and Alzheimer’s disease (AD) are characterized by protein misfolding, and can lead to dementia. However, prion diseases are infectious and transmissible, while AD is not. The similarities and differences between these diseases have led researchers to perform comparative studies. In the last 2 decades, progress has been made in immunotherapy using anti-prion protein and anti-β-amyloid antibodies. In this study, we review new ideas and strategies for therapeutic antibodies targeting prion diseases and AD through conformation dependence.

关键词： prion Alzheimer’s disease immunotherapy antibody conformation

One-Branch Zero-IF Wireless Receiver Topology with Multiphase Local Oscillator

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Transactions of Tianjin university 2010年第2期16卷 109-113页

作者：李金城仇玉林 school of Electronics and Information Engineering Beijing Jiaotong University Institute of Microelectronics Chinese Academy of Sciences

This paper proposes a one-branch zero-IF receiver topology, which samples the I and Q signals of the modulated RF carrier with one signal path by means of a multiphase local oscillator. The suggested one-branch re- ceiver works without matching problem, and it is also capable of cancelling out the flicker noise and DC-offset when the local oscillator is configured to the four-phase mode. The one-branch receiver saves much area and power com- pared with the traditional two-branch ones. All of the advantages above make the one-branch receiver topology a promising architectural candidate for low-power and low-cost RF CMOS receiver designs. Keywords： RF CMOS; zero-IF; flicker noise; image rejection; low-power; IQ matching

关键词： RF CMOS zero-IF flicker noise image rejection low-power IQ matching

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支持向量机在货运量预测中的应用研究

铁道学报 2004年第4期26卷 10-14页

作者：赵闯刘凯李电生北京交通大学交通运输学院北京100044

在分析现有货运量预测方法所存在问题的基础上,建立了货运量预测的支持向量机模型,并以我国1981～2001年的货运量和相关经济指标的历史统计数据作为学习样本,分别选用3种不同的核函数,通过拟合训练和外推预测分析,验证了支持向量机用于... 详细信息

在分析现有货运量预测方法所存在问题的基础上,建立了货运量预测的支持向量机模型,并以我国1981～2001年的货运量和相关经济指标的历史统计数据作为学习样本,分别选用3种不同的核函数,通过拟合训练和外推预测分析,验证了支持向量机用于货运量预测的有效性,并对模型中的有关参数进行了探讨分析。

关键词：货运量预测支持向量机

Hopfield Neural Network Approach to Clustering in Mobile Radio Networks

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通信学报 1995年第4期16卷 40-44页

作者： Jiang Yan Li Chengshu(Northern jiaotong university,beijing 100044) 北方交通大学北京

ＨｏｐｆｉｅｌｄＮｅｕｒａｌＮｅｔｗｏｒｋＡｐｐｒｏａｃｈｔｏＣｌｕｓｔｅｒｉｎｇｉｎＭｏｂｉｌｅＲａｄｉｏＮｅｔｗｏｒｋｓＪｉａｎｇＹａｎ；ＬｉＣｈｅｎｇｓｈｕ（ＮｏｒｔｈｅｒｎＪｉａｏｔｏｎｇＵｎｉｖｅｒｓｉｔｙ... 详细信息

ＨｏｐｆｉｅｌｄＮｅｕｒａｌＮｅｔｗｏｒｋＡｐｐｒｏａｃｈｔｏＣｌｕｓｔｅｒｉｎｇｉｎＭｏｂｉｌｅＲａｄｉｏＮｅｔｗｏｒｋｓＪｉａｎｇＹａｎ；ＬｉＣｈｅｎｇｓｈｕ（ＮｏｒｔｈｅｒｎＪｉａｏｔｏｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１０００４４）Ａｂ...

关键词：藿普菲尔神经网串级连接移动无线电网

Magnetic properties of tin-doped ferrites nanoparticles Sn_xFe_(3-x)O_4

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Rare Metals 2006年第Z1期25卷 493-497页

作者： LU Yanwu OU Yiyu LIU Fangxin Department of Physics Beijing Jiaotong University Beijing 100044 China Department of Physics Beijing Jiaotong University Beijing 100044 China Department of Astronomy and Applied Physics University of Science & Technology of China Hefei 230026 China

Nanoparticles of tin-doped ferrites SnxFe3-xO4 (x=0, 0.1, 0.2, 0.3, 0.4, 1.0) were prepared by the precipitation exchange method. The particles of all specimens are crystalline with mean diameter in the range of 4-8 nm, and the lattice parameters enlarge with increasing tin content. Magnetization and Mssbauer data indicate that the specimens are paramagnetic. The saturation magnetization decreases, as well as the magnetization and the coercive field increase, with increasing tin-content, the possible causes of which were discussed.

关键词： tin-doped ferrite quantum composition article-size effect paramagnetic properties

Network layered priority mapping theory

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Science china(Information Sciences) 2010年第9期53卷 1713-1726页

作者： YANG Dong*,ZHANG HongKe,SONG Fei&LI ShiYong National Engineering Laboratory for Next Generation Internet Interconnection Devices, school of Electronics and Information Engineering,beijing jiaotong university,beijing 100044,china National Engineering Laboratory for Next Generation Internet Interconnection Devices School of Electronics and Information Engineering Beijing Jiaotong University Beijing China

In the early days of the Internet layered design,the information between layers did not exchange in large amount *** the rapid growth of the Internet,the emergence of many technologies such as service data partition,multi-connection and multi-path has made it possible to frequently exchange complex information between *** regard to these changes,this paper introduces "network layered priority mapping(NLPM)" for future Internet *** NLPM aims to maximize the satisfaction of the Internet *** NLPM is designed to differentiate priority of the information on different layers and integrate the information using priority *** NLPM,network services can be delivered more efficiently;network utilization such as the utilization of connection,path and channel can also be *** analysis,NS simulation and prototype implementation have proved the efficiency of NLPM.

关键词： future Internet layered priority mapping

STUDY ON FLAT MANAGEMENT APPLYING TO BUS STRUCTURE INNOVATION

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STUDY ON FLAT MANAGEMENT APPLYING TO BUS STRUCTURE INNOVATIO...