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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第8期8卷 1246-1255页

作者： yan zhi-guo WANG zhi-zhong REN Xiao-mei Departmen of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200030 China

This paper presents an effective and efficient combination of feature extraction and multi-class classifier for motion classification by analyzing the surface electromyografic(sEMG) signals. In contrast to the existing methods,considering the non-stationary and nonlinear characteristics of EMG signals,to get the more separable feature set,we introduce the empirical mode decomposition(EMD) to decompose the original EMG signals into several intrinsic mode functions(IMFs) and then compute the coefficients of autoregressive models of each IMF to form the feature set. Based on the least squares support vector machines(LS-SVMs) ,the multi-class classifier is designed and constructed to classify various motions. The results of contrastive experiments showed that the accuracy of motion recognition is improved with the described classification scheme. Furthermore,compared with other classifiers using different features,the excellent performance indicated the potential of the SVM techniques embedding the EMD-AR kernel in motion classification.

关键词： Electromyografic signal Empirical mode decomposition (EMD) Auto-regression model Wavelet packet transform Least squares support vector machines (LS-SVM) Neural network

Modeling and Performance Analysis of Dispatching Policies in Dispatcher-Based Web Server Cluster

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Wuhan University Journal of Natural Sciences 2006年第3期11卷 591-595页

作者： XIONG zhi yan Puliu guo Chengcheng School of Electronic Information Wuhan UniversityWuhan 430072 Hubei China

There are two kinds of dispatching policies in content-aware web server cluster; segregation dispatching policy and mixture dispatching policy. Traditional scheduling algorithms all adopt mixture dispatching policy. They do not consider that dynamic requests＇ serving has the tendency to slow down static requests＇ serving, and that different requests have different resource demands, so they can not use duster＇s resource reasonably and effectively. This paper uses stochastic reward net （SRN） to model and analyze the two dispatching policies, and uses stochastic Petri net package （SPNP） to simulate the models. The simulation results and practical tests both show that segregation dispatching policy is better than mixture dispatching policy. The principle of segregation dispatching policy can guide us to design efficient scheduling algorithm.

关键词： Web server cluster stochastic reward net mixture dispatching policy segregation dispatching policy

MoS2 nanosheet arrays supported on hierarchical porous carbon with enhanced lithium storage properties

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Chinese Chemical Letters 2017年第4期28卷 743-747页

作者： zhi-yan guo yang Zhong Yu Liu Chang-Ming Mao Gui-Cun Li College of Materials Science and Engineering Qingdao University of Science and Technology Qingclao 266042 China

MoS_2 nanosheet arrays supported on hierarchical nitrogen-doped porous carbon（MoS_2@C） have been synthesized by a facile hydrothermal approach combined with high-temperature *** hierarchical nitrogen-doped porous carbon can serve as three-dimensional conductive frameworks to improve the electronic transport of semiconducting MoS_*** evaluated as anode material for lithium-ion batteries,the MoS_2@C exhibit enhanced electrochemical performances compared with pure MoS_2 nanosheets,including high capacity（1305.5 mAhg^（-1） at lOOmAg^（-1））,excellent rate capability（438.4mAhg^（-1） at 1000mAg^（-1））.The reasons for the improved electrochemical performances are explored in terms of the high electronic conductivity and the facilitation of lithium ion transport arising from the hierarchical structures of MoS_2@C.

关键词： Molybdenum disulfide Hydrothermal Nitrogen-doped porous carbon Anode material Lithium-ion batteries

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大口径新型顶管力学行为现场试验研究

岩土工程学报 2017年第10期39卷 1842-1850页

作者：张耀闫治国朱合华同济大学土木工程防灾国家重点实验室上海200092 同济大学土木工程学院地下建筑与工程系上海200092

通过对新型预应力钢筒混凝土顶管(JPCCP)开展现场试验,得到了在施工荷载、水土压力等三维荷载作用下顶管各部位的应变时程响应;同时也获得了顶进过程中管–土接触应力时程变化。根据对数据的分析,得出预应力钢筒混凝土顶管具有较大的纵... 详细信息

通过对新型预应力钢筒混凝土顶管(JPCCP)开展现场试验,得到了在施工荷载、水土压力等三维荷载作用下顶管各部位的应变时程响应;同时也获得了顶进过程中管–土接触应力时程变化。根据对数据的分析,得出预应力钢筒混凝土顶管具有较大的纵向抗压刚度,而纵向抗拉刚度不足。由于预应力的效应,内层混凝土与中间层混凝土能够承受较大的环向拉应力。通过对管节的纵向受力分析,计算出管–土平均摩阻力随顶进距离的变化规律,结合施工记录得出平均摩阻力随顶进距离先增大后减小,最小值为1.27 k Pa;同时,施工顶进间隔越短,平均摩阻力越小。此外,实测结果表明,管–土接触应力对管节运动较为敏感,最大瞬时值可达500 k Pa;施工结束后,接触应力沿管周分布并不对称或均匀,但与实测管节环向应变分布对应。

关键词：预应力钢筒混凝土顶管管–土接触应力管–土平均摩阻力应变时程响应

Fast Fourier Transform-based Support Vector Machine for Prediction of G-protein Coupled Receptor Subfamilies

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Acta Biochimica et Biophysica Sinica 2005年第11期37卷 759-766页

作者： yan-zhi guo Meng-Long LI Ke-Long WANG zhi-Ning WEN Min-Chun LU Li-Xia LIU Lin JIANG College of Chemistry,Sichuan University,Chengdu 610064,China College of Chemistry Sichuan UniversityChengdu 610064China

Although the sequence information on G-protein coupled receptors(GPCRs)continues togrow,many GPCRs remain orphaned(*** specificity unknown)or poorly characterized with littlestructural information available,so an automated and reliable method is badly needed to facilitate the identifi-cation of novel *** this study,a method of fast Fourier transform-based support vector machinehas been developed for predicting GPCR subfamilies according to protein’s *** classifyingClass B,C,D and F subfamilies,the method achieved an overall Matthew’s correlation coefficient andaccuracy of 0.95 and 93.3%,respectively,when evaluated using the jackknife *** method achieved anaccuracy of 100% on the Class B independent *** results show that this method can classify GPCRsubfamilies as well as their functional classification with high accuracy.A web server implementing theprediction is available at http://***/blast/Pred-GPCR.

关键词： G-protein coupled receptor subfamily fast Fourier transform support vector machine prediction

Study of New Hot Metal Desulfurization Process on 1t Desulfurization Experiments

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Journal of Iron and Steel Research International 2011年第S2期18卷 125-128页

作者： REN Xiao-dong, ZHANG Ting-an, DOU zhi-he, LIU yan, Lü guo-zhi, HE Ji-cheng (School of Material and Metallurgy, Northeastern University, Shenyang 110004, Liaoning, China)

For the lack of the present hot metal desulfurization processes in iron and steel industry, our group has proposed the in-situ mechanical stirring method for external desulfurization of molten iron and researched this new method. This paper investigated this new in-situ mechanical stirring hot metal desulphurization process on desulphurization experiments of one-ton scale by using the new desulfurizer. The experimental results indicated that the desulfurization efficiency of in-situ mechanical stirring desulfurization process is 90% and the lowest sulfur content in the treated hot metal is 23ppm. By comparing with the methods of direct throwing desulfurizer and in-situ injecting desulfurization, in-situ mechanical stirring desulfurization process is the suitable desulfurizaton method.

关键词： desulfurization 1t stirring, in-situ mechanical stirring desulphurization process

The renaissance of oxo synthesis: heterogeneous Rh-catalyzed hydroformylation

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Science China Chemistry 2025年

作者： Tao yan zhi Cao State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences National Energy Center for Coal to Clean Fuels Synfuels China Technology Co. Ltd.

Hydroformylation could convert olefins and syngas （mixture of H2and CO） into aldehydes with a great atomic *** transformation serves as one of the most prominent processes in modern chemical industry, as it provides over 10million tons of aldehydes as feedstock for our daily essential products such as plasticizers, paints, solvents, and pharmaceuticals. This process generally requires efficient yet robust catalyst to realize decent efficacy. Compared with metals such as Co, Ru, and Pd, rhodium （Rh）-based catalysts stand out due to its superior activity even under mild reaction conditions, and dominate over 70%of global hydroformylation processes.

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火灾高温下盾构衬砌结构试验与力学模型综述

中国公路学报 2017年第8期30卷 15-23+48页

作者：朱合华周龙沈奕闫治国同济大学土木工程防灾国家重点实验室同济大学地下建筑与工程系上海市政工程设计研究总院(集团)有限公司

复杂运营环境下自然与人为因素所引发的众多隧道火灾已造成了重大的社会影响和经济损失。火灾已成为威胁隧道安全运营的主要灾害之一,其对隧道衬砌结构会产生严重的损伤乃至破坏。盾构衬砌为装配式结构,接缝多以螺栓连接,火灾高温下易... 详细信息

复杂运营环境下自然与人为因素所引发的众多隧道火灾已造成了重大的社会影响和经济损失。火灾已成为威胁隧道安全运营的主要灾害之一,其对隧道衬砌结构会产生严重的损伤乃至破坏。盾构衬砌为装配式结构,接缝多以螺栓连接,火灾高温下易发生管片爆裂和接缝连接薄弱部位受损而诱发的突然破坏;同时,由于盾构隧道周围地层的约束作用有限,其衬砌结构体系受火损坏后垮塌的风险极高。为提高软土地层环境下盾构隧道装配式衬砌结构体系的耐火能力及火灾安全性,本文调研了盾构隧道火灾安全研究现状,对与盾构隧道火灾安全研究相关的试验及理论分析工作做了较为全面的综述,主要包括:火灾高温下盾构隧道衬砌管片力学特性试验与理论分析模型,火灾高温下管片接缝力学特性试验与理论分析模型,火灾高温下盾构衬砌体系力学特性试验与理论分析模型,火灾高温下盾构隧道周围地层力学行为研究。在此基础上,针对大直径盾构隧道的火灾试验,高温引起的盾构衬砌管片材料性能劣化评价及主动式抗火管片的材料设计,火灾高温条件下盾构衬砌结构计算模型精细化这3个核心问题,展望了盾构衬砌受火灾影响的研究方向和思路。

关键词：盾构隧道火灾高温综述衬砌结构火灾试验力学模型

Local Sequence Information-based Support Vector Machine to Classify Voltage-gated Potassium Channels

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Acta Biochimica et Biophysica Sinica 2006年第6期38卷 363-371页

作者： Li-Xia LIU Meng-Long LI Fu-Yuan TAN Min-Chun LU Ke-Long WANG yan-zhi guo zhi-Ning WEN Lin JIANG College of Chemistry,Sichuan University.Chengdu 610064,China CollegeofChemistry SichuanUniversityChengdu610064China

In our previous work,we developed a computational tool,PreK-ClassK-ClassKv,to predictand classify potassium (K~+) *** K+ channel prediction (PreK) and classification at family level(ClassK),this method performs ***,it does not perform so well in classifying voltage-gatedpotassium (Kv) channels (ClassKv).In this paper,a new method based on the local sequence information ofKv channels is introduced to classify Kv *** transmembrane domains of a Kv channel protein areused to define a protein,and the dipeptide composition technique is used to transform an amino acid sequenceto a numerical sequence.A Kv channel protein is represented by a vector with 2000 elements,and a supportvector machine algorithm is applied to classify Kv *** method shows good performance withaverages of total accuracy (Acc),sensitivity (SE),specificity (SP),reliability (R) and Matthews correlationcoefficient (MCC) of 98.0%,89.9%,100%,0.95 and 0.94 *** results indicate that the localsequence information-based method is better than the global sequence information-based method to classifyKv channels.

关键词： voltage-gated potassium channel classification transmembrane domain dipeptide composition support vector machine

基于示教与视觉纠偏的机器人自动焊接方法研究

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机器人 2007年第3期29卷 256-260页

作者：鄢治国徐德李原谭民中国科学院自动化研究所复杂系统与智能科学实验室北京理工大学信息科学技术学院北京100081

给出了一种示教与纠偏相结合的焊缝跟踪方法,用于实现机器人的自动焊接.针对传统的示教再现机器人,由激光视觉传感器测量实际路径与示教路径之间的偏差.机器人控制器根据示教路径和偏差,对焊枪的运动方向和位置进行调整,实现焊缝跟踪.... 详细信息

给出了一种示教与纠偏相结合的焊缝跟踪方法,用于实现机器人的自动焊接.针对传统的示教再现机器人,由激光视觉传感器测量实际路径与示教路径之间的偏差.机器人控制器根据示教路径和偏差,对焊枪的运动方向和位置进行调整,实现焊缝跟踪.利用六自由度机器人和激光结构光视觉传感器设计了实验系统,对所提方法进行了实验.实验结果验证了该方法的有效性.

关键词：视觉传感器图像处理焊缝跟踪