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Research on common issues for relationship between mechanism degree of freedom,driving link and executive link

Science China(Technological Sciences) 2009年第4期52卷 966-974页

作者： WANG AiLun College of Mechanical & Electrical engineering, Central South University, Changsha 41.083, China Key Laboratory of Modern Complex Equipment {1. and Extreme Manufacturing, Ministry of Education, Changsha 41.083, China 1. College of Mechanical & Electrical engineering Central South University Changsha 410083 China 2. Key Laboratory of Modern Complex Equipment design and Extreme Manufacturing Ministry of Education Changsha 410083 China

During engineering practice and theoretical research, the mechanism degree of freedom is sometimes unequal to the number of the driving link, which is unable to be explained according to the classic theory of the mechanism degree of freedom. To solve this problem, the duality description for operating laws of mechanism is introduced based on the concepts of duality. The Junction-Structure Equation is established for the port descriptions of general ideal mechanism and the functional description for the mechanism degree of freedom is described by utilization of bond graph theory. The force-transfer de- gree of freedom, i.e. the antithesis concept of movement-transfer degree of freedom, is introduced and defined based on the analysis of energy transfer as well as the analysis of signal causality. By utiliza- tion of structural description, functional description and duality description for the equation of degree of freedom, the relationship between the movement-transfer degree of freedom and force-transfer de- gree of freedom is further explored and analyzed. Thus, the relationship between the mechanism de- gree of freedom upon the driving link and the executive link is described generally. Finally, some typical relationships between the mechanism degree of freedom, the driving link and the executive link are analyzed.

关键词： duality bond graph Junction-Structure Equation driving link executive link degree of freedom

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New Strategy to Construct Fused/Bridged/Spiro Carbocyclic Scaffolds Based on the design of Novel 6-C Synthon Precursor

New Strategy to Construct Fused/Bridged/Spiro Carbocyclic Sc...

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第十六届全国金属有机化学学术讨论会

作者： Jia Liu,~(1.2) Xi Wang,~1.Chang-Liang Sun,~1.Bi-Jie Li,~1.Min Wang,~2 zhang-Jie Shi~(*1.3) 1.Beijing National Laboratory of Molecular Sciences(BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular engineering of Ministry of Education,College of Chemistry and Molecular engineering and Green Chemistry Center,Peking University,Beijing 1.0871.and department of Chemistry,2 University of Agriculture of China,Beijing 1.0094 and 3 State Key laboratory of Organometallic Chemistry,Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,Shanghai 200032,China

＜正＞Fused/bridged/spiro carbocyclic ring scaffolds are one of most important motifs in natural and synthetic organic *** design a new 6-C synthon,which could be applied to construct complex poly-,spiro-and bridged systems through the simple sequential chemical transformations from acyclic precursor by a one-pot strategy from

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Controller Synthesis of Continuous-Time Piecewise Linear Systems Based on Piecewise Lyapunov Functions

Controller Synthesis of Continuous-Time Piecewise Linear Sys...

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第三十届中国控制会议

作者： QIU Jianbin~1.FENG Gang~2,GAO Huijun~1.1.Space Control and Inertial Technology Research Center,Harbin Institute of Technology,Harbin 1.0001.P.R.China 2.department of Manufacturing {1. and {1. Management,City University of Hong Kong,Kowloon,Hong Kong

This paper investigates the robust H static output feedback(SOF) controller design for a class of continuous- time piecewise linear *** objective is to design a piecewise SOF controller guaranteeing the asymptotic stability of the resulting closed-loop system with a prescribed H disturbance attenuation *** on common/piecewise Lyapunov functions combined with Projection Lemma and some convexiflcation techniques,some new results to the SOF controller design are developed for the underlying continuous-time piecewise linear *** is shown that the controller gains can be obtained by solving a set of linear matrix inequalities,which are numerically efficient with commercially available software.A simulation example is also given to illustrate the effectiveness of the proposed approaches.

关键词： Piecewise Linear Systems Output Feedback Piecewise Lyapunov Functions Controller design

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基于韦布尔分布的行人过街特性模型

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土木工程学报 2009年第1期42卷 114-118页

作者：姚荣涵景超王殿海大连理工大学辽宁大连116024 吉林大学吉林长春130022

行人过街特性对信号配时设计具有重要影响。为说明行人穿越机动车流的过街特性,基于韦布尔分布函数描述了机动车车头时距分布,并得到行人在一次穿越一条车道、多条车道或一个方向三种穿越方式下的穿越概率、平均等待间隔数、平均等待时... 详细信息

行人过街特性对信号配时设计具有重要影响。为说明行人穿越机动车流的过街特性,基于韦布尔分布函数描述了机动车车头时距分布,并得到行人在一次穿越一条车道、多条车道或一个方向三种穿越方式下的穿越概率、平均等待间隔数、平均等待时间和平均延误等特性。利用长春市典型路段调查数据,验证机动车车头时距分布的韦布尔模型;并对各种穿越方式的行人过街特性进行对比分析。结果表明:韦布尔函数描述的机动车车头时距分布与实测分布接近,检验效果在置信度为95%时非常显著;行人单独穿越内、外侧车道的特性差异不大,而同时穿越内、外侧车道的概率明显偏小,且平均等待间隔数和平均延误明显偏大;行人穿越人行横道时逐车道、逐方向和一次穿越的总延误依次增加。基于韦布尔分布的行人过街特性模型能够很好地解释行人过街行为,可以为城市行人交通设施设计和信号优化提供理论依据。

关键词：行人交通韦布尔分布过街特性

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Existence Condition on Solutions to the Algebraic Riccati Equation

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自动化学报 2008年第1期34卷 85-87页

作者： NI Mao-Lin~1.1.National Laboratory of Space Intelligent Control,Beijing Institute of Control engineering,China Academy of Space Technology,Beijing 1.0080,P.R.China National Laboratory of Space Intelligent Control Beijing Institute of Control Engineering China Academy of Space Technology Beijing 100080 P. R. China

First,the existence conditions on the solutions to the algebraic Riccati equation are ***,a strict proof is presented for a necessary and sufficient condition on the exis- tence of a unique optimal positive definite solution to this equa- *** using this condition,some untrue results on the design of robust decentralized controllers are corrected.

关键词： Riccati equation optimal control robust control stability decentralized control

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煤层气定向羽状水平井开采机理与应用分析

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天然气工业 2005年第1期25卷 114-116页

作者：鲜保安高德利李安启赵庆波曹雯石油大学中国石油勘探开发研究院廊坊分院

定向羽状水平井技术适合于开采低渗透储层的煤层气,集钻井、完井与增产措施于一体。定向羽状水平井的主要机理在于多分支井眼在煤层中形成网状通道,促进微裂隙的扩展,又能连通微裂隙和裂缝系统,提高单位面积内的气液两相流的导流... 详细信息

定向羽状水平井技术适合于开采低渗透储层的煤层气,集钻井、完井与增产措施于一体。定向羽状水平井的主要机理在于多分支井眼在煤层中形成网状通道,促进微裂隙的扩展,又能连通微裂隙和裂缝系统,提高单位面积内的气液两相流的导流能力,大幅度提高了井眼波及面积,降低煤层气和游离水的渗流阻力,提高气液两相流的流动速度,进而提高煤层气产量和采出程度。沁水煤层气田是中国典型的低渗透煤层气藏,具有煤层厚度和深度适中、渗透率低、煤岩机械强度高、含气量和饱和度高的特点,适合于定向羽状水平井技术条件。在煤层气藏地质参数不变的情况下,可利用分支井产量模型研究分支数和分支段长对产能的影响关系,分支数和分支段长是影响产能的敏感性人为因素,也是可以通过工程设计优化加以改变的工程参数,从而尽可能发挥定向羽状水平井的产能潜力。通过经济评价,利用定向羽状水平井技术开发沁水煤层气田具有较高的经济效益。

关键词：煤层气定向羽状水平井开采机理增产微裂隙气液两相流

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多缸汽油机全可变液压气门系统的开发与试验研究

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内燃机工程 2017年第3期38卷 105-111页

作者：李小蕊谢宗法常英杰张炯黄硕李小霞山东大学机械工程学院济南250061 山东大学高效洁净机械制造教育部重点试验室济南250061 龙口中宇热管理系统科技有限公司烟台265700

提出了一种适用于4缸汽油机的全可变液压气门系统,通过凸轮驱动和液压传动使进气门开启,通过开启控油阀使进气门回落,通过调节控油阀的泄油时刻改变进气门的最大升程和开启持续角。建立了气门运动规律测量试验台架,并对全可变液压气门... 详细信息

提出了一种适用于4缸汽油机的全可变液压气门系统,通过凸轮驱动和液压传动使进气门开启,通过开启控油阀使进气门回落,通过调节控油阀的泄油时刻改变进气门的最大升程和开启持续角。建立了气门运动规律测量试验台架,并对全可变液压气门系统的气门升程进行了试验测量。试验结果表明:该系统可实现最大气门升程在0到最大设计升程之间连续可变,进气门开启持续角在曲轴转角0°~284°之间连续可变。进一步研究表明:全可变液压气门系统按汽油机标定转速5 000r/min高速运行时,在不同气门升程下均未出现气门运动规律的"失真"现象,说明该系统能够满足汽油机高速运行的需求。试验还发现多缸机液压气门机构存在相互干涉问题,通过改进设计控油阀结构,消除了由此导致的气门异常开启现象。

关键词：内燃机多缸汽油机全可变液压气门系统气门升程气门异常开启

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Analysis of variance for testing method of cement in determination of strength

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Progress in Natural Science:Materials International 2011年第4期21卷 341-346页

作者： Hong HUANG,Xiao-dong SHEN State Key Laboratory of Materials-Oriented Chemical engineering,College of Material Science and engineering, Nanjing University of Technology,Nanjing 21.009,China State Key Laboratory of Materials-Oriented Chemical engineering College of Material Science and Engineering Nanjing University of Technology Nanjing 210009 China

The statistical tools such as descriptive statistics,full factorial design and analysis of source of variation were used to identify the potential factors that impact the validity of testing method for determining the strength of *** results showed that personal error impacted both accuracy and precision of test *** time associated with temperature fluctuation resulted in strength variation but did not impact the precision of test in all curing *** compactions did not impact the precision of test but resulted in the strength variation on 3 d and 28 d *** methods for the initial moist air curing significantly impacted the precision of testing method and resulted in the strength variation of cement on 1.d.

关键词： testing method of cement analysis of variance strength accuracy precision

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Protein Secondary Structure Prediction Based on Improved SVM Method in Compound Pyramid Model

Protein Secondary Structure Prediction Based on Improved SVM...

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201. Chinese Control and Decision Conference

作者： Bingru Yang~1.Wu Qu~1.Yun zhai~(1.2),Haifeng Sui~1.1.School of Information engineering,University of Science and Technology Beijing,Beijing 1.0083 2.College of Computer Science,Liaocheng University Liaocheng,252059,China

＜正＞Methods for predicting protein secondary structure provide information that is useful both in ab initio structure prediction and as additional restraints for fold recognition *** structure predictions may also be used to guide the design of site directed mutagenesis studies,and to locate potential functionally important *** this article,we propose a method of improved SVM for predicting protein secondary *** evolutionary information contained in amino acid’s physicochemical properties, position-specific scoring matrix generated by psi-blast as input to improved SVM,secondary structure can be predicted at significantly increased *** on KDTICM theory,we have constructed a compound pyramid model,which is composed of four layers of the intelligent interface and integrated in several ways, such as improved SVM,mixed-modal BP,KDD* method and so *** the RS1.6 data set,state overall per-residue accuracy,Q3 reached 83.06%,while SOV99 accuracy increased to 80.6%.On the cb51. data set, Q3 reached 80.49%,SOV99 accuracy increased to 79.84%.This article briefly introduces this model and highlights the improved SVM method.

关键词： Protein Second Structure SVM Compound Pyramid Model

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Sensitivity analysis with the modified Heaviside function for the optimal layout design of multi-component systems

Sensitivity analysis with the modified Heaviside function fo...

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The Seventh China-Japan-Korea Joint Symposium on Optimization of Structural and Mechanical Systems

作者： Jihong zhu1.Liang Xia1.Weihong zhang1.1.0} Simulation and Aerospace Computing (ESAC) The Key Laboratory of Contemporary {1. and Integrated Manufacturing Technology Northwestern Polytechnical University Xi’an Shaanxi 71.072 China

There are two kinds of design variables involved in the layout design of multi-component systems: pseudo-density variables associated with the framework structure and location design variables associated with connected *** sensitivities with respect to the first kind of variables can be easily carried out as in topology optimization,but the semi-analytical method （SAM） is often used for sensitivity analysis with respect to the location design *** to the geometric perturbation of the finite element mesh,the latter can then be regarded as a geometric perturbation model （GPM）.In this paper,we propose a material perturbation model （MPM） using fixed finite element （FE） mesh for sensitivity analysis with respect to location design *** material discontinuity across the boundary between each component and the framework structure can be smoothed approximately by a modified Heaviside *** a location design variable of a certain component is perturbed,attached finite elements to the component boundary are assumed to undertake only a shift of material properties while the finite element mesh itself remains geometrically *** a result,the sensitivity with respect to location design variables can be achieved as easily as for pseudo-density *** computing efficiency is thus improved because the velocity field for the mesh perturbation in the semi-analytical scheme is no longer *** MPM is illustrated by means of numerical tests,especially the optimization in 3D multi-component systems design.

关键词： Multi-component system modified Heaviside function Sensitivity analysis Topology optimization Geometric perturbation model Material perturbation model

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