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STUDY ON DYNAMIC CURVING BEHAVIOR OF TILTING PASSENGER CARS

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Chinese Journal of Mechanical engineering 2002年第4期15卷 360-365,371页

作者： Liu Hongyou Zeng Jing National Traction Power Laboratory, southwest jiaotong university, chengdu 610031, China National Traction Power Laboratory Southwest Jiaotong University Chengdu 610031 China

By using tilting carbodies, train can negotiate at a higher speed withoutreducing the passenger's ride quality. This is a good method to allow a significant increase inspeed at existing track to improve the railway transportation capability, and to enhance thecompetition ability of railways with other transportation systems. With the increase of the curvenegotiation speed, the wheel-rail lateral forces and wheel-rail wear of the tilting train willincrease. The self-steering radial bogie is an effective way to solve the problem. The dynamic modelof the tilting passenger car with self-steering bogies is established in detail, and the curvingperformance of the car is investigated.

关键词： tilting passenger car self-steering bogie dynamic curving behavior wheel-rail interaction

Entropy Assessment on Environmental Influence of Condense Heat in Recovery System in Air-Conditioning Refrigerating Machine

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湖南大学学报（自然科学版） 2009年第S1期36卷 96-101页

作者： TANG Wen-wu1,2,WANG Han-qing1,2(1.school of Energy Science and engineering,Central South university,Changsha,Hunan 410083,China 2.school of civil engineering,Hunan university of Technology,Zhuzhou,Hunan 412008,China) school of Energy Science and engineering Central South University Changsha 410083 China school of civil engineering Hunan University of Technology Zhuzhou 412008 China

This paper presented an entropy evaluation method for the influences of condense heat recovery system on the *** at the damage of the condense heat to the environment,an entropy of resource loss and an emission entropy from the condense heat recovery system in the air conditioning refrigerating machine were *** the evaluation of the entropies,we developed a new algorithm for the parameter identification,called the composite influence coefficient,based on the Least Squares Support Vector Machine *** simulation,the numerical experiments shows that the Least Squares Support Vector Machine method is one of the powerful methods for the parameter identification to compute the damage entropy of the condense heat,with the largest training error being-0.025(the relative error being-3.56%),and the biggest test error being 0.015(the relative error being 2.5%).

关键词： air-conditioning refrigerating machine condense heat entropy evaluation LS-SVM

Reliability analysis of ship structure system with multi-defects

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Science China(Physics,Mechanics & Astronomy) 2010年第11期53卷 2113-2124页

作者： AN Hai 1,AN WeiGang 1 & ZHAO WeiTao 2 1 school of Aerospace and civil engineering,Harbin engineering university,Harbin 150001,China 2 school of Aeronautics and Astronautics,Shenyang Institute of Aeronautical engineering,Shenyang 110034,China 1. school of Aerospace and civil engineering Harbin Engineering University Harbin 150001 China2. School of Aeronautics and Astronautics Shenyang Institute of Aeronautical Engineering Shenyang 110034 China

This paper analyzes the influence of multi-defects including the initial distortions,welding residual stresses,cracks and local dents on the ultimate strength of the plate element,and has worked out expressions of reliability calculation and sensitivity analysis of the plate *** analysis is made for the system with multi-defects plate *** mechanism,failure paths and the calculating approach to global reliability index are also worked *** plate elements with multi-defects fail,the formula of reverse node forces which affect the residual structure is deduced,so are the sensitivity expressions of the system reliability *** ensures calculating accuracy and rationality for reliability analysis,and makes it convenient to find weakness plate elements which affect the reliability of the structure ***,for the validity of the approach proposed,we take the numerical example of a ship cabin to compare and contrast the reliability and the sensitivity analysis of the structure system with multi-defects with those of the structure system with no *** approach has implications for the structure design,rational maintenance and renewing strategy.

关键词： initial distortions welding residual stresses cracks and local defects ultimate strength reverse node forces sensitivity expression reliability analysis

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斜交连续箱梁桥的温度应力与位移研究

铁道学报 2009年第4期31卷 82-86页

作者：张元海李乔兰州交通大学土木工程学院甘肃兰州730070 西南交通大学土木工程学院四川成都610031

以单根斜梁模型模拟斜交连续箱梁,在三力矩方程基础上,分析非线性日照梯度温度作用下斜交连续箱梁的温度应力和位移,系统研究斜度和弯扭刚度比对三跨斜交连续箱梁温度应力和位移的影响,绘制的大量曲线清晰显示了其影响规律。研究结果表... 详细信息

以单根斜梁模型模拟斜交连续箱梁,在三力矩方程基础上,分析非线性日照梯度温度作用下斜交连续箱梁的温度应力和位移,系统研究斜度和弯扭刚度比对三跨斜交连续箱梁温度应力和位移的影响,绘制的大量曲线清晰显示了其影响规律。研究结果表明,在常用斜度范围内,中跨梁底拉应力和梁顶压应力随斜度的增大而减小,随弯扭刚度比的增大而增大;边跨跨中有较大的上拱位移,且其值随斜度的增大而减小,随弯扭刚度比的增大而增大;中跨跨中位移随斜度增大将由下挠转变为上拱,其临界斜度随弯扭刚度比的增大而增大。

关键词：斜交箱梁斜交连续梁温度应力温度位移非线性温度梯度

Guided wave propagation in multilayered piezoelectric structures

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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 1094-1104页

作者： GUO YongQiang1, CHEN WeiQiu2,3 & ZHANG YongLiang4 1 Key Laboratory of Mechanics on Disaster and Environment in Western China, Ministry of Education, and school of civil engineering and Mechanics, Lanzhou university, Lanzhou 730000, China 2 Key Laboratory of Soft Soils and Geoenvironmental engineering, Ministry of Education, and Department of civil engineering, Zhejiang university, Hangzhou 310058, China 3 Department of engineering Mechanics, Zhejiang university, Hangzhou 310027, China 4 school of civil engineering, Lanzhou jiaotong university, Lanzhou 730070, China Key Laboratory of Mechanics on Disaster and Environment in Western China Ministry of Education and School of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China Key Laboratory of Soft Soils and Geoenvironmental engineering Ministry of Education and Department of Civil Engineering Zhejiang University Hangzhou 310058 China Department of engineering Mechanics Zhejiang University Hangzhou 310027 China school of civil engineering Lanzhou Jiaotong University Lanzhou 730070 China

A general formulation of the method of the reverberation-ray matrix (MRRM) based on the state space formalism and plane wave expansion technique is presented for the analysis of guided waves in multilayered piezoelectric structures. Each layer of the structure is made of an arbitrarily anisotropic piezoelectric material. Since the state equation of each layer is derived from the three-dimensional theory of linear piezoelectricity, all wave modes are included in the formulation. Within the framework of the MRRM, the phase relation is properly established by excluding exponentially growing functions, while the scattering relation is also appropriately set up by avoiding matrix inversion operation. Consequently, the present MRRM is unconditionally numerically stable and free from computational limitations to the total number of layers, the thickness of individual layers, and the frequency range. Numerical examples are given to illustrate the good performance of the proposed formulation for the analysis of the dispersion characteristic of waves in layered piezoelectric structures.

关键词： multilayered piezoelectric structures the method of reverberation-ray matrix guided waves dispersion characteristic

Normal scalar curvature and a pinching theorem in S^m×R and H^m×R

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Science China Mathematics 2011年第9期54卷 1977-1984页

作者： CHEN Qun 1,2 & CUI Qing 3,1,1 school of Mathematics and Statistics,Wuhan university,Wuhan 430079,China 2 International Center for Theoretical Physics,Trieste 34100,Italy 3 school of Mathematics,southwest jiaotong university,chengdu 610031,China school of Mathematics and Statistics Wuhan University Wuhan China International Center for Theoretical Physics Trieste Italy school of Mathematics Southwest Jiaotong University Chengdu China

We obtain an inequality in Sm×R and Hm×R which is similar to DDVV *** an application,we show that a minimal submanifold in H m×R with nonnegative scalar curvature must be a surface of the type γ×R,where γ is a g... 详细信息

关键词： product spaces DDVV conjecture pinching theorem

Homogenization-based multi-scale damage theory

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Science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 690-698页

作者： LI Jie 1,2 & REN XiaoDan 1 1 school of civil engineering, Tongji university, Shanghai 200092, China 2 State Key Laboratory of Disaster Reduction in civil engineering, Shanghai 200092, China 1. school of civil engineering Tongji University Shanghai 200092 China2. State Key Laboratory of Disaster Reduction in Civil Engineering Shanghai 200092 China

The research of modern mechanics reveals that the damage and failure of structures should be considered on different scales. The present paper is dedicated to establishing the multi-scale damage theory for the nonlinear structural analysis. Starting from the asymptotic expansion based homogenization theory, the multi-scale energy integration is proposed to bridge the gap between the micro and macro scales. By recalling the Helmholtz free energy based damage definition, the damage variable is represented by the multi-scale energy integration. Hence the damage evolution could be numerically simulated on the basis of the unit cell analysis rather than the experimental data identification. Finally the framework of the multi-scale damage theory is established by transforming the multi-scale damage evolution into the conventional continuum damage mechanics. The agree- ment between the simulated results and the benchmark results indicates the validity and effectiveness of the proposed theory.

关键词： Multi-scale damage representation asymptotic method constitutive model numerical simulation

Identification and Characterization of hmr19 Gene Encoding a Multidrug Resistance Efflux Protein from Streptomyces hygroscopicus *** Strain 10-22

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 519-528页

作者： Lei QIN , Heng-An WANG1 , Zhong-Qin WU, Xiao-Feng ZHANG, Mei-Lei JIN,Zi-Xin DENG2, and Guo-Ping ZHAOShanghaiResearch Center of Biotechnology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences,Graduate school of the Chinese Academy of Sciences, Shanghai 200233, China 1school of Agriculture and Biology, Shanghai jiaotong university, Shanghai 201101, China 2school of Life Science and Biotechnology, Shanghai jiaotong university, Shanghai 200030, China ShanghaiResearch Center of Biotechnology Shanghai Institute for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences school of Agriculture and Biology Shanghai Jiaotong University

The hmr19 gene was cloned from Streptomyces hygroscopicus subsp. yingchengensis strain 10- 22, a bacterium strain producing agricultural antibiotics. Sequence similarity comparison indicates that hmr19 gene may encode a predicted protein with 14 putative transmembrane α-helical spanners, belonging to the drug:H+ antiporter-2 family of the major facilitator superfamily. The expression of hmr19 in the mycelium of strain 10-22 was detected by Western blotting analysis. Gene replacement technology was employed to construct an hmr19 disruption mutant. The growth inhibition test against different antibiotics indicated that the mutant strain was 5–20 fold more susceptible to tetracycline, vancomycin and mitomycin C than the parental wild type strain. The mutant took up tetracycline much faster and accumulated more antibiotics than the wild type strain 10-22. While with the addition of an energy uncoupler, carbonyl cyanide m- chlorophenylhydrazone, the characteristics of the accumulation of [3H]tetracycline in these two strains were almost the same. It was thus concluded that hmr19 encoded a multidrug resistance efflux protein.

关键词： multidrug resistance (MDR) gene replacement (knockout) Streptomyces Streptomyces hygroscopicus subsp. yingchengensis strain 10-22

A Method Combining Numerical Analysis and Limit Equilibrium Theory to Determine Potential Slip Surfaces in Soil Slopes

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Journal of Mountain Science 2011年第5期8卷 718-727页

作者： XIAO Shiguo YAN Liping CHENG Zhiqiang Department of Geological engineering Southwest Jiaotong University Chengdu 610031 China Los Angeles Department of Water and Power Los Angeles USA Department of Applied Mechanics and engineering Southwest Jiaotong University Chengdu 610031 China

This paper describes a precise method combining numerical analysis and limit equilibrium theory to determine potential slip surfaces in soil slopes. In this method, the direction of the critical slip surface at any point in a slope is determined using the Coulomb’s strength principle and the extremum principle based on the ratio of the shear strength to the shear stress at that point. The ratio, which is considered as an analysis index, can be computed once the stress field of the soil slope is obtained. The critical slip direction at any point in the slope must be the tangential direction of a potential slip surface passing through the point. Therefore, starting from a point on the top of the slope surface or on the horizontal segment outside the slope toe, the increment with a small distance into the slope is used to choose another point and the corresponding slip direction at the point is computed. Connecting all the points used in the computation forms a potential slip surface exiting at the starting point. Then the factor of safety for any potential slip surface can be computed using limit equilibrium method like Spencer method. After factors of safety for all the potential slip surfaces are obtained, the minimum one is the factor of safety for the slope and the corresponding potential slip surface is the critical slip surface of the slope. The proposed method does not need to pre-assume the shape of potential slip surfaces. Thus it is suitable for any shape of slip surfaces. Moreover the method is very simple to be applied. Examples are presented in this paper to illustrate the feasibility of the proposed method programmed in ANSYS software by macro commands.

关键词： Soil slope Stress field Potential slip surface Slope stability Factor of safety Numerical analysis Limit equilibrium method ANSYS software