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人体颈、腕动脉压力波互相关特征及在冠心病上的应用

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上海交通大学学报 2009年第7期43卷 1066-1070页

作者：张本岭丁光宏薛松吴强孙仁上海交通大学船舶海洋与建筑工程学院上海200240 上海市针灸经络研究中心上海201203 上海交通大学医学院附属仁济医院上海200001 中国人民解放军工程兵指挥学院徐州221003

采用Hilbert-Huang变换(HHT)方法对人体颈动脉、腕动脉脉搏压力波进行同步信号分析,对健康志愿者以及冠心病患者术前、术后的颈、腕同步脉搏波分别进行模态分解,同时引入互相关方法,从而得到健康志愿者以及冠心病患者术前、术后的颈、... 详细信息

采用Hilbert-Huang变换(HHT)方法对人体颈动脉、腕动脉脉搏压力波进行同步信号分析,对健康志愿者以及冠心病患者术前、术后的颈、腕同步脉搏波分别进行模态分解,同时引入互相关方法,从而得到健康志愿者以及冠心病患者术前、术后的颈、腕同步脉搏压力波各阶相应模态之间的互相关特征.通过互相关特征曲线发现,健康人体颈、腕动脉第2阶模态的波形周期对应于其脉搏周期的1/3,第3阶模态的波形周期对应于其脉搏周期的1/2,第4阶模态与脉搏波周期相近.健康人体颈动脉、腕动脉第1阶模态均呈现较为标准的X波模态.冠心病患者颈、腕动脉第1阶模态互相关特征明显变异,术后相应模态特征得到显著改善.

关键词：同步脉搏波 Hilbert-Huang变换互相关方法冠心病

A measurement error model for microarray data analysis

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Progress in Natural Science:Materials International 2005年第7期15卷 614-620页

作者： ZHOU Yiming and CHENG Jing ( Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, china State Key Laboratory of Biomembrane and Membrane Biotechnology, Tsinghua University, Beijing 100084, china national engineering Research center for Beijing biochip Technology, 18 Life Science Parkway, Beijing 102206, china) Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China. State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing 100084 China. national engineering Research center for Beijing biochip Technology 18 Life Science Parkway Beijing 102206 China

Microarray technology has been widely used to analyze the gene expression levels by detecting fluorescence intensity in a high throughput fashion. However, since the measurement error produced from various sources in microarray experiments is heterogeneous and too large to be ignored, we propose here a measurement error model for microarray data processing, by which the standard deviation of the measurement error is demonstrated to be linearly increased with fluorescence intensity. A robust algorithm, which estimates the parameters of the measurement error model from a single microarray without replicated spots, is provided. The model and algorithm for estimating of the parameters from a given data set are tested on both the real data set and the simulated data set, and the result has been proven satisfactory. And, combining the measurement error model with traditional Z-test method, a full statistical model has been developed It can significantly improve the statistical inference for identifying differentially expressed genes.

关键词： microarray measurement error model parameter estimation differentially expressed genes.

Target tracking in wireless sensor networks using adaptive measurement quantization

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Science china(Information Sciences) 2012年第4期55卷 827-838页

作者： ZHOU Yan 1,2,LI JianXun 2 & WANG DongLi 1 1 Colleage of Information engineering,Xiangtan University,Xiangtan 411105,china 2 Department of Automation,shanghai Jiao Tong University,shanghai 200240,china 1. Colleage of Information engineering Xiangtan University Xiangtan 411105 China2. Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

Quantization/compression is usually adopted in wireless sensor networks (WSNs) since each sensor node typically has very limited power supply and communication *** consider the problem of target tracking in a WSN with quantized measurements in this *** is focused on the design of measurement quantizer with adaptive *** on the probability density function (PDF) of the signal amplitude measured at a random location and by maximizing the entropy,an adaptive design method for quantization thresholds is *** to the nonlinear measuring and quantization models,particle filtering (PF) is adopted in the fusion center (FC) to estimate the target *** Cram'er-Rao lower bounds (CRLBs) for tracking accuracy using quantized measurements are also ***,a simulation example on tracking single target with noisy circular trajectories is provided to illustrate the effectiveness of the proposed approach.

关键词： target tracking wireless sensor network adaptive quantization posterior Cram’er-Rao lower bound

Rietveld Quantitative Analysis of Carbides Precipitation in Normalized-tempered 2.25Cr-1Mo-0.25V Steel

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 922-926页

作者：张永涛张汉谦 School of Materials Science and engineering Shanghai Jiaotong University Research Institute Baoshan Iron & Steel Co.Ltd.

The quantitative determination of the mass fractions of precipitates in steels is very difficult using traditional materials characterization techniques. The Rietveld full-pattern fitting algorithm was introduced to solve this problem. The precipitated multicomponents’ mass fraction of M3C, MC, M7C3 and M23C6 were evaluated precisely and relatively quickly. It is found evolution of carbides apparently occurs during tempering at high temperatures, and a two-step transformation mechanism is proposed for M7C3 during early tempering treatment. The method is an effective way on the investigation of precipitation kinetics, which may play a promising role in propertities’ enhancement and design of the heat-resistant steels.

关键词： 2.25Cr-1Mo-0.25V steel rietveld quantitative analysis precipitates

Large-eddy simulations and vortex structures of turbulent jets in crossflow

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Science china(Physics,Mechanics & Astronomy) 2007年第1期50卷 118-132页

作者： GUAN Hui1,2 & WU ChuiJie2 1 School of Mechanical and Power engineering,East china University of Science and Technology,shanghai 200237,china 2 Research center for Fluid Dynamics,PLA University of Science and Technology,Nanjing 211101,china 1. School of Mechanical and Power engineering East China University of Science and Technology Shanghai 200237 China 2. Research center for Fluid Dynamics PLA University of Science and Technology Nanjing 211101 China

Using the method of large-eddy simulation, the 3-dimensional turbulent jets in crossflow with stream-wise and transverse arrangements of nozzle are simulated, emphasizing on the dynamical process of generation and evolution of vortex structures in these flows. The results show that the basic vortex structures in literatures, such as the counter-rotating vortex pair, leading-edge vortices, lee-side vortices, hanging vortices, kidney vortices and anti-kidney vortices, are not independent physical substances, but local structures of the basic vortex structure of turbulent jets in crossflow-the 3-D stretching vortex rings originating from the orifice of the nozzle, which is discovered in this study. Therefore, the most important large-scale structures of turbulent jets in crossflow are unified to the 3-D vortex rings which stretch and twist in stream-wise and swing in transverse directions. We also found that the shedding frequencies of vortex rings are much lower than the one corresponding to the appearance of leading-edge and lee-side vortices in the turbulent jets.

关键词： turbulent jet in crossflow coherent structure large-eddy simulation

Channel-aware and queue-aware joint-layer resource optimization for cognitive radio networks

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Science china(Information Sciences) 2010年第12期53卷 2576-2583页

作者： GUO KunQi 1,2,SUN LiXin 1,LI Yong 2 & JIA ShiLou 3 1 School of Computer Science and Telecommunication engineering,Jiangsu University,Zhenjiang 212013,china 2 Research center for Wireless Communication,shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences,shanghai 200050,china 3 Communication Research center,Harbin Institute of Technology,Harbin 150001,china 1. School of Computer Science and Telecommunication engineering Jiangsu University Zhenjiang 212013 China2. Research Center for Wireless Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China3. Communication Research Center Harbin Institute of Technology Harbin 150001 China

An optimization model is derived to maximize the utilization efficiency of the idle channels of primary users(PU) in cognitive radio *** the optimization model,Lyapunov optimization method is used to allocate the idle channels of PU to secondary user(SU) most *** time distribution of the idle channels of PU is predicted by a low-pass time *** algorithm is proposed to implement the optimization *** algorithm is efficient because of using a greedy selection *** efficiency of the algorithm is demonstrated by mathematic analyses and simulation results.

关键词： cognitive radio networks Lyapunov optimization resource utilization primary user secondary user

RADIAL EXTRUSION PROCESS BY THREE-DIMENSIONAL RIGID-PLASTIC FEM SIMULATION

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中国有色金属学会会刊：英文版 1997年第4期7卷 48-52页

作者： Chen Jun, Peng Yinghong, Zuo Xu, Ruan Xueyu national Die & Mold CAD engineering Research center, shanghai Jiao Tong University, shanghai 200030

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ＲＡＤＩＡＬＥＸＴＲＵＳＩＯＮＰＲＯＣＥＳＳＢＹＴＨＲＥＥＤＩＭＥＮＳＩＯＮＡＬＲＩＧＩＤＰＬＡＳＴＩＣＦＥＭＳＩＭＵＬＡＴＩＯＮ①ＣｈｅｎＪｕｎ，ＰｅｎｇＹｉｎｇｈｏｎｇ，ＺｕｏＸｕ，ＲｕａｎＸｕｅｙｕＮａｔｉｏｎａｌＤｉｅ＆ＭｏｌｄＣＡＤＥｎ...

关键词： radial extrusion three dimensional rigid plastic FEM numerical simulation

Modeling Study of the Particle Pinning Effect on the Grain Boundary Movement

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Journal of Iron and Steel Research International 2011年第S1期18卷 342-345页

作者： WANG Xue-lun 1,FU Li-ming 2,WANG Wei 3,JIA Zhi-xin 1 (1.Rizhaosteel Technology center,Rizhao Iron and Steel Co Ltd.Rizhao 276806,china 2.School of Materials Science and engineering,shanghai Jiaotong University,shanghai 200240 china 3 Department of Structural Steels,Baosteel Research Institute,shanghai 201900,china) Rizhao Iron & Steel Co Ltd Rizhaosteel Technol Ctr Rizhao 276806 Peoples R China shanghai Jiao Tong Univ Sch Mat Sci & Engn Shanghai 200240 Peoples R China Baosteel Res Inst Dept Struct Steels Shanghai 201900 Peoples R China

In this work,based on the classical grain boundary (GB) formula and the principle of work-energy conversion,a new physically-based model has been developed to predict the particle pinning force concerning the interaction between second phase particles (SPPs) and the moving *** effect of particles pinning on the GB movement is *** modeling results can be applied to quantitatively determine the critical numbers of SPPs required for complete pining the grain growth,such as the critical SPPs number of the unit GB area,the critical number for single grain stagnation,the critical volume fraction of particles at a given particle *** predictions are in good agreement with the experimental results by Gladman.

关键词： the second-phase particle pinning force physical-based model

SYNTHESIS OF DIAMMINEPLATINUM(Ⅱ)ASCORBATE AND STRUCTURE COMPARISON WITH ITS DACH DERIVATIVES

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Chinese Chemical Letters 1991年第2期2卷 121-122页

作者： Zhong Xian HUANG Zhen QIU Ming Qin CHENG Xie Jing LI Dept.of Chemistry,Fudan University,shanghai,china 200433 Dept.of Chemical engineering,shanghai University of engineering Science,shanghai,china 200335center of Measurement and Analysis,Fudan University,shanghai,china 200433

An antitumour complex,cis-diammineplatinum(Ⅱ)ascorbate,has been synthesized and its X-ray structure is *** chemistry calculation compared with its diaminecyclohexane derivatives indicates that they have different ele... 详细信息

关键词： SYNTHESIS OF DIAMMINEPLATINUM ASCORBATE AND STRUCTURE COMPARISON WITH ITS DACH DERIVATIVES ITS