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METHOD TO SOLVE ELASTIC CONJUGATE SURFACES IN MULTI-TEETH MESHING

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Chinese Journal of Mechanical engineering 2002年第4期15卷 348-352页

作者： Yi ChuanyunSchool of Mechanical science and engineering, huazhong university of science and technology,wuhan 430074, china School of Mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074

A method to solve the elastic conjugate surfaces in multi-teeth meshing ispresented. In mechanical manufacturing and design, there exist a lot of problems relating toconjugate surfaces, such as three-dimensional engagement, steel rolling and workpiece machining,which cause great effects on the quality of machining and performances of transmission. This methoddescribes relation between conjugate motion and elastic deformation in the process of mesh-in andmesh-out, and can be used to determine the profile of gear tooth by a certain given load sharing.

关键词： multi-teeth meshing elastic conjugate surfaces

The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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science china(Technological sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3, WANG Guilan1 & ZHENG Qiguang2 1. School of Material science and technology, huazhong university of science and technology, wuhan 430074, china 2. institute of Laser technology and engineering, huazhong university of science and technology, wuhan 430074, china 3. Mechanical engineering College, Hubei university of technology, wuhan 430068, china 1. School of Material science and technology Huazhong University of Science and Technology Wuhan 430074 China 3. Mechanical engineering College Hubei University of Technology Wuhan 430068 China 2. institute of Laser technology and engineering Huazhong University of Science and Technology Wuhan 430074 China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

PROFILE TOLERANCE EVALUATION OF PARAMETRIC CURVES AND SURFACES

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Chinese Journal of Mechanical engineering 2002年第2期15卷 121-125页

作者： Huang Xiaoping Xiong YoulunSchool of Mechanical science and engineering, huazhong university of science and technology,wuhan 430074, china School of Mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074 China ***

The profile error evaluation of complex curves and surfaces expressed inparametric form is considered. The linear error model is established on the base of two hypothesesfirstly. Then the profile error evaluation is converted into one of these optimal formulations:MINIMAX, MAXMIN and MINIDEX problems, which are easier to be solved than the initial form. To eachone of them, geometric condition and algebraic condition are presented to arbitrate whether theideal element reaches to the optimal position. Exchange algorithm is proven highly effective insearching for solutions to these optimization problems. At last some key problems in tolerance offreeform surfaces and curves in B spline method are discussed.

关键词： Parametric form Profile tolerance Linear error model Exchangealgorithm

Particle swarm optimization algorithm for partner selection in virtual enterprise

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Progress in Natural science:Materials International 2008年第11期18卷 1445-1452页

作者： Qiang Zhao~a Xinhui Zhang~(b,*) Renbin Xiao~c a School of Mechanical science and engineering,huazhong university of science and technology,wuhan 430074,china b Department of Biomedical,Industrial & Human Factors engineering,Wright State university,Dayton,OH 45435,USA c institute of systems engineering,huazhong university of science and technology,wuhan 430074,china School of Mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074 China Department of Biomedical Industrial & Human Factors Engineering Wright State University Dayton OH 45435 USA institute of systems engineering Huazhong University of Science and Technology Wuhan 430074 China

Partner selection is a fundamental problem in the formation and success of a virtual *** partner selection problem with precedence and due date constraint is the basis of the various extensions and is studied in this paper.A nonlinear integer program model for the partner selection problem is *** problem is shown to be NP-complete by reduction to the knapsack problem,and therefore no polynomial time algorithm *** solve it efficiently,a particle swarm optimization(PSO)algorithm is adopted,and several mechanisms that include initialization expansion mechanism,variance mechanism and local searching mechanism have been developed to improve the performance of the proposed PSO algorithm.A set of experiments have been conducted using real examples and numerical simulation,and have shown that the PSO algorithm is an effective and efficient way to solve the partner selection problems with precedence and due date constraints.

关键词： Virtual enterprise Partner selection PSO NP-complete

An architecture for mobile database management system

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Journal of university of science and technology Beijing 2002年第2期9卷 156-160页

作者： Dong Li and Yucai Feng Computer School, huazhong university of science and technology, wuhan 430074, china Computer School Huazhong University of Science and Technology Wuhan 430074 China

In order to design a new kind of mobile database management system (DBMS)more suitable for mobile computing than the existent DBMS, the essence of database systems in mobilecomputing is analyzed. An opinion is introduced that the mobile database is a kind of dynamicdistributed database, and the concept of virtual servers to translate the clients' mobility to theservers' mobility is proposed. Based on these opinions, a kind of architecture of mobile DBMS, whichis of versatility, is presented. The architecture is composed of a virtual server and a local DBMS,the virtual server is the kernel of the architecture and its functions are described. Eventually,the server kernel of a mobile DBMS prototype is illustrated.

关键词： mobile database dynamic distributed database DBMS architecture virtual server data region

Applications of semigroups of operators to non-elliptic differential operators

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Chinese science Bulletin 2000年第8期45卷 673-682页

作者： ZHENG QuanDepartment of Mathematics, huazhong university of science and technology, wuhan 430074, china Department of Mathematics Huazhong University of Science and Technology Wuhan China

This paper treats systematically the semigroup method of non-elliptic differential operators, which was developed in the last ten years. In particular, a review of the applications of regularized semigroups to non-elliptic differential operators with constant coefficients or time-dependent coefficients, parabolic systems, correct systems, abstract differential operators and pseudodifferential operators is given here. It is also shown that the regularized semigroup is an appropriate tool for non-elliptic differential operators and is far superior to the integrated semigroup approach.

关键词： differential operator regularized semigroup integrated semigroup initial value problem Fourier multiplier.

Neural Nets:Another Paradigm for Decision Support

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Journal of systems engineering and Electronics 1995年第2期6卷 2-8页

作者： Feng Shan (Dept. of ACE, huazhong university of science and technology, wuhan 430074, china) Dept. of ACE Huazhong University of Science and Technology Wuhan 430074 China

The paper presents an important aspect of Neural Nets application, i. e., their usefulness for decision support. The essential feature of the neural net approach to decision making is that it is a black-box approach, which means one does not try to model the underlying processes, but only looks for a tuning of the parameters of the neural net such that the black-box mimics the sensible behavior. Through the existing widespread applications in industry, business and science, the paper emphasizes their common property as a paradigm for decision support.

关键词： Neural network Neural-net controller Decision support Industrial applications.

Numerical simulations and experimental investigations on transverse effects of two-wave mixing in a photovoltaic photorefractive crystal

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science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 856-863页

作者： CAI Xin1,2,LIU JinSong1 & WANG ShengLie1 1 wuhan National Laboratory for Optoelectronics,School of Optoelectronic science and engineering,huazhong university of science and technology,wuhan 430074,china 2 School of science,wuhan university of technology,wuhan 430070,china 1. wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China2. School of Science Wuhan University of Technology Wuhan 430070 China

The transverse effects of two Gauss waves mixing in a photovoltaic photorefractive crystal,i.e.,the dynamical evolutions of signal beam with different parameters,are traced numerically and *** the one-dimensional numerical simulations and two-dimensional experimental investigations show that the self-focusing effect of signal beam becomes more obvious as the intensity of pump beam and the angle between the signal and pump beams *** accordance with these results,the state of two Gaussian waves mixing is controllable.

关键词： numerical simulation experimental investigation two-wave mixing transverse effects Gaussian distribution

The Researches on Path Independence Problem

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Journal of systems engineering and Electronics 1998年第2期9卷 19-22页

作者： Luo Yunfeng Xiao Renbin & Zhu Mingfu(institute of systems engineering, huazhong university of science and technology,wuhan 430074, P. R. china) institute of systems engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China

Rationality condition is imposed in Arrow's General Possibility Theorem in order for social choice to be independent of the path of choice. In this Paper, emphasis is laid on the analysis of the relevance of path independence and rationality condition. Two kinds of Path independence, i.e., Plott's path independence and Bandyopadhyay's sequential path independence, are shown, and their meanings with respect to the problem are investigated.

关键词： Social choice Rationality condition Path independence Sequential path independence