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Multi-dimensional project management models for mega-construction companies and their applications

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Science china(Technological Sciences) 2011年第S1期54卷 118-124页

作者： LIN ZhengHang 1,2.QIANG MaoShan 1,2.TANG WenZhe 1,2.FAN QiXiang 3.&LIU Qiang 4 1 Institute of Project Management and Construction Technology,Tsinghua University,Beijing 100084,{3. 2.State Key Laboratory of Hydraulic and engineering,Tsinghua University,Beijing 100084,{3. 3.{3. Three Gorges Corporation,Yichang 443.02.{3. 4 School of Software,Tsinghua University,Beijing 100084,{3. Institute of Project Management and Construction Technology Tsinghua University Beijing China State Key Laboratory of Hydraulic and engineering Tsinghua University Beijing China china Three Gorges Corporation Yichang China School of Software Tsinghua University Beijing China

china is undertaking an increasing number of mega-infrastructure projects along with its rapid economic *** participants in these projects,understand how to adapt the proper and efficient management strategies is *** this paper,we propose three distinct models for companies under various background and management requirements,based on sophisticated data analysis and model ***,we successfully committed these models with hydropower development projects and achieved a great progress in enhancing management efficiency.

关键词： project management models mega-construction companies applications hydropower development companies

A fast stereoscopic video coding algorithm based on JMVM

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Science china(Information Sciences) 2011年第6期54卷 1218-1226页

作者： DENG ZhiPin 1,2., JIA KeBin 1 , CHAN YuiLam 2., FU ChangHong 2.& SIU WanChi 2.1 Department of Electronic Information & Control engineering, Beijing University of Technology, Beijing 10012., china 2.Department of Electronic Information engineering, Hong Kong Polytechnic University, Hong Kong, china Department of Electronic Information & Control engineering Beijing University of Technology Beijing China Department of Electronic Information engineering Hong Kong Polytechnic University Hong Kong China

In order to exploit the intra-view and inter-view dependencies in stereo video coding, a fast joint motion and disparity estimation algorithm is proposed in this paper. An efficient search strategy based on the motion-disparity constraint is developed, in which both the motion and disparity vectors can be obtained simultaneously with low complexity. Moreover, a credible initial predictive vector set is designed with the aid of the temporal and spatial neighboring blocks so that the coding efficiency can be further enhanced. The experimental results demonstrate that the proposed algorithm can reduce more than 96% coding time compared with the JMVM full search with a negligible quality drop.

关键词： H.2.4 stereoscopic video coding disparity estimation motion estimation

Mechanical Properties of Two Kinds of New Cold-Formed Flange-Closed Welding Section Members

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沈阳建筑大学学报（自然科学版） 2011年第6期27卷 1021-1032页

作者：武胜 College of Civil engineering Northeast Forestry University Workstation for Postdoctoral Fellows of Heilongjiang Construction engineering Group Research Station on Civil engineering for Postdoctoral Fellows of Harbin Institute of Technology

The hollow flange beam(HFB) is a unique cold-formed steel section developed in Australia for use as a flexural ***′s a particular cross section with two torsion rigid closed triangular flanges and a comparatively flexible web,and it is a type of high efficient cross *** paper presents two kinds of new cold-formed flange-closed welding sections named HF1 and HF2.according to different section component and parameters of *** finite element method has been adopted to investigate the mechanical properties such as buckling mode,deformation process,rigidity,ductility and correlation curve of two kinds of new section members which being subjected to axial compression,flexure,combined compression and *** comparisons of the consumed steel quantities of per unit load carrying capacity between new section members and the same section dimensions of cold-formed C-section members have been carried *** conclusions can be drawn from above work that the new sections have some superior properties including higher load carrying capacity and section modulus,sufficient section stiffness,and difficult occurrence for the sub element local *** new sections are suitable for bearing flexure,compression,combined compression and *** new sections′ consumed steel quantities of per unit load carrying capacity are almost half as those of the same dimension C-section members′.The experimental investigation is carried out further on the new cold-formed flange-closed welding section members and can be used in the practical engineering.

关键词： hollow flange beam cold-formed steel members finite element analysis mechanical properties

Orientation-Singularity Representation and Orientation-Capability Computation of a Special Class of the Gough-Stewart Parallel Mechanisms Using Unit Quaternion

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Chinese Journal of Mechanical engineering 2012年第6期25卷 1096-1104页

作者： LI Baokun1, 2. CAO Yi1, 3. *, ZHANG Qiuju1, and HUANG Zhen4 1 School of Mechanical engineering, Jiangnan University, Wuxi 2.412., china 2.School of Mechanical engineering, Anhui University of Science and Technology, Huainan 2.2.01, china 3.State Key Laboratory of Fluid Power Transmission and Control, Hangzhou 3.002., china 4 Robotics Research Center, Yanshan University, Qinhuangdao 066004, china School of Mechanical engineering Jiangnan University Wuxi China School of Mechanical engineering Anhui University of Science and Technology Huainan China State Key Laboratory of Fluid Power Transmission and Control Hangzhou China Robotics Research Center Yanshan University Qinhuangdao China

Singular configuration seriously affects the performance of the Gough-Stewart parallel mechanism and has attracted many researchers’ attentions. However, most of existing topics often focus on the position-singularity of the mechanism for a constant-orientation, but few reports research the orientation-singularity for a given position. In order to investigate the orientation-singularity of the Gough-Stewart parallel mechanisms with two dissimilar semi-regular hexagonal platforms for a given position, after constructing the discrimination matrix of the singular configuration of the mechanism and computing the determinant of this matrix by using unit quaternion as the orientation parameters which can avoid the singularities in parameterization, a general symbolic expression representing the three-dimensional orientation-singularity locus for a given position is obtained and the three-dimensional view of the orientation-singularity locus is further described. The orientation-singularity-free void exists inside the orientation-singularity locus, but the shape of the orientation-singularity-free void is irregular and inconvenient for the design of the mechanism. The minimal inscribed sphere of the three-dimensional orientation-singularity locus namely the orientation-singularity-free ball is described. The radius of the ball orientation-capability is used as the measurement for the orientation-singularity-free void size. A new efficient algorithm is proposed for the computation of the orientation-capability. Finally, the influences of the geometry parameters and the different positions of the mechanism on the orientation-capability are discussed. A new method of the singularity analysis of the Gough-Stewart parallel mechanism is advanced based on the unit quaternion, and the research finds have important referential value for the configuration parameters optimization of this class of the parallel mechanisms with the goal of having the maximal singularity-free zone.

关键词： parallel mechanism unit quaternion orientation-singularity orientation-singularity-free void orientation-capability

A new policy to solve routing conflicts in shuffle-exchange networks

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Science china(Information Sciences) 2011年第7期54卷 1512-1523页

作者： GE FangBin 1,ZHAO Min 1,ZHANG Tao 1 & WANG JianXin 2.1 College of Command Automation PLA University of Science and Technology,nanjing 2.0007,{3. 2.Institute of {3. Electronic System engineering,Beijing 10003.,{3. College of Command Automation PLA University of Science and Technology Nanjing China Institute of china Electronic System engineering Beijing China

Batch routing is an important approach for solving routing conflicts in SE (shuffle-exchange) ***,the complexity of batching and the uncertainty of batch size makes this approach *** on sequence division and routing coding concepts,we propose a method for detecting routing conflicts in an SE network,known as dividing detection that is more efficient than the method for window *** addition,a new conjecture relating to routing policies in SE networks is *** is proved using a constructive approach when n < *** on the conjecture,a new routing scheme for SE networks is *** this scheme,all the input signals can be transfered without conflicts and within two batches,while the efficiency of the batch routing is noticeably improved.

关键词： shuffle-exchange network sequence division routing coding transition sequence educed sequence

An efficient method for detecting concurrency errors in object-oriented programs

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Science china(Information Sciences) 2012年第12期55卷 2774-2784页

作者： HE YanXiang 1,2.WU Wei 2.& CHEN Yong 2.1 School of Computers,Wuhan University,Wuhan 43.072.china 2.State Key Laboratory of Software engineering,Wuhan University,Wuhan 43.072.china School of Computers Wuhan University Wuhan China State Key Laboratory of Software engineering Wuhan University Wuhan China

Multicore and multi-threaded processors have become the norm for modern ***,concurrent programs have become more and more prevalent despite being difficult to write and *** errors are highly likely to appear in concurrent code,conventional error detection methods such as model checking,theorem proving,and code analysis do not scale smoothly to concurrent *** is an indispensable technique for detecting concurrency errors,but it involves a great deal of manual work and is *** paper presents an automatic method for detecting concurrency errors in classes in object-oriented *** method uses a heuristic algorithm to automatically generate test cases that can effectively trigger ***,each test case is executed automatically and a fast method is adopted to identify the actual concurrency error from anomalous run *** have implemented a prototype of the method and applied it to some typical Java *** shows that our method is more effective and faster than previous work.

关键词： concurrency error dynamic test data race atomicity violations test case generation

Research on the Characters of the Cutting Force in Vibration Cutting Particle Reinforced Metal Matrix Composites SiC_p/Al

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厦门大学学报（自然科学版） 2002年第S1期41卷 74-75页

作者： LIU Chuan-shao 1, ZHAO Bo 1,2. GAO Guo-fu 1, JIAO F eng 1 (1. Department of Mechanical engineering, Jiaozuo Institute of Techno logy, Henan 454000, china 2. Institute of Mechanical engineering, Shanghai Jiaotong University, Shanghai 2.003., china)

In this paper, turning experiments of machining particle reinforced metal matri x composites(PRMMCs) SiC p/Al with PCD tools have been carried out. The cutting force characteristics in ultrasonic vibration turning compared with that in com mon turning were studied. Through the single factor experiments and multiple fac tor orthogonal experiments, the influences of three kinds of cutting conditions such as cutting velocity, amount of feed and cutting depth on cutting force were analyzed in detail. Meanwhile, according to the experimental data, the empirica l formula of main cutting force in ultrasonic vibration turning was conclude d. According to the test results, the cutting force is direct proportion to cutt ing depth basically according to the relation between cutting force and other fa ctors, which is similar to that of common cutting, so is the feed rate, but the influence is not so big. The influence of cutting speed is larger than that of f eed rate on cutting force because the efficient cutting time increases in vibrat ion cycle with the increase of cutting speed, which causes cutting force to incr ease. The research results indicate: (1) Ultrasonic vibration turning possesses much lower main cutting force than that in common turning when adopting smaller cutting parameters. If using larger cutting parameters, the difference will inco nspicuous. (2. There are remarkable differences of cutting force-cutting veloci ty characteristics in ultrasonic vibration turning from that in common turning m ainly because built-up edge does not emerge in ultrasonic turning unlike common turning in corresponding velocity range. (3. In ultrasonic vibration cutting, t he influence of cutting velocity on cutting force is most obvious among thre e cutting parameters and the influence of feed is smallest. So adopting lower cu tting velocity and larger cutting depth not only can reduce cutting force effect ively but also can ensure cutting efficiency. (4) The conclusions are usefu

关键词： composite SiC p/Al PCD tool ultrasonic vibrati on turning cutting force

Safe and Objective Assay of Enterovirus 71 Neutralizing Antibodies via Pseudovirus

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Chemical Research in Chinese Universities 2012年第1期28卷 91-95页

作者： JIN Jun1, XU Lin1, GUO Shi-jie2. SUN Shi-yang1, ZHANG Shu1, ZHU Chang-lin3. KONG Wei1 and JIANG Chun-lai1 1. National engineering Laboratory for AIDS Vaccine, College of Life Science, Jilin University, Changchun 13.012. P. R. {3. 2. Department of Pediatrics, the First Hospital of Jilin University, Changchun 13.02., P. R. {3. 3. Changchun Baike Biotechnology Co., Changchun 13.012. P. R. {3. National engineering Laboratory for AIDS Vaccine College of Life Science Jilin University Changchun 130012 Department of Pediatrics the First Hospital of Jilin University Changchun 130021 Changchun Baike Biotechnology Co. Changchun 130012

Current serum neutralization assays based on the inhibition of the cytopathic effect（Nt-CPE） need to ma nipulate live viruses, which are time-consuming, labor-intensive, and have the potential exposure to infectious agents, so a safe and objective assay via pseudovirus for the fast and efficient detection of enterovirus 71（EV71） neutralizing antibodies was developed. First, we generated EV71 pseudovirus containing firefly luciferase gene in place of the capsid gene P1 in EV71 genome. Vero cells infected with 2.0 CCID50（50% cell culture infective dose） of EV71 pseudovirus for 2. h were found to have the best performance. Seval sera were measured by EV71 pseudoparticle neutralization assay（Nt-PPN） and the conventional serological method Nt-CPE. Neutralizing antibody titers measured by Nt-PPN and those obtained by Nt-CPE demonstrate a high correlation between the two methods. Overall, the PPN assay represents a valid alternative to conventional serological methods for the evaluation of EV71 neutralizing anti bodies. This method can be used for detecting neutralizing antibodies of other picornaviruses, such as hepatitis A vi rus（HAV） and coxsackievirus 16（CVA16）, and make it possible to determine whether there is cross-reactivity be tween EV71 and CVA16.

关键词： Enterovirus 71(EV71) Pseudovirus Luciferase Neutralizing antibody assay

基于模糊物元分析的溃坝生命损失模糊预测模型

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水电能源科学 2011年第8期29卷 46-49,45页

作者：王少伟包腾飞陈兰河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098 河海大学水资源高效利用与工程安全国家工程研究中心江苏南京210098 河海大学水利水电学院江苏南京210098

基于国内溃坝生命损失资料,结合了前人研究结果,调整了溃坝风险人口死亡率的影响因素,并根据模糊物元分析法获得的溃坝风险人口死亡率,提出了风险人口死亡率修正系数,构建了溃坝生命损失模糊预测模型。实例结果表明,该模型预测精度较高... 详细信息

基于国内溃坝生命损失资料,结合了前人研究结果,调整了溃坝风险人口死亡率的影响因素,并根据模糊物元分析法获得的溃坝风险人口死亡率,提出了风险人口死亡率修正系数,构建了溃坝生命损失模糊预测模型。实例结果表明,该模型预测精度较高,实用性较强。

关键词：模糊物元分析溃坝生命损失 AHP法预测模型