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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 43.074, China 2. Institute of Laser technology and engineering, Huazhong university of science and technology, Wuhan 43.074, China 3. Mechanical engineering college, Hubei university of technology, Wuhan 43.068, China School of Material science and technology Huazhong University of Science and Technology Wuhan China Mechanical engineering college Hubei University of Technology Wuhan China Institute of Laser technology and engineering Huazhong University of Science and Technology Wuhan 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.

Peak structure in the interlayer conductance of Moirésuperlattices

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Chinese Physics B 2024年第10期33卷 376-380页

作者： Yizhou Tao Chao Liu Mingwen Xiao henan Fang college of Electronic and Optical engineering&college of Flexible Electronics(Future {3.) Nanjing University of Posts and TelecommunicationsNanjing 210023China Department of Physics Nanjing UniversityNanjing 210093China

We investigate the peak structure in the interlayer conductance of Moirésuperlattices using a tunneling theory wedeveloped *** theoretical results predict that,due to the resonance of two different partial waves,the doublepeakstructure can appear in the curve of the interlayer conductance versus twist ***,we study the influencesof the model parameters,i.e.,the chemical potential of electrodes,the thickness of Moirésuperlattice,and the strength ofinterface potential,on the peak structure of the interlayer *** particular,the parameter dependence of the peakstructure is concluded via a phase diagram,and the physical meanings of the phase diagram is ***,thepotential applications of the present work is discussed.

关键词： Moirésuperlattice interlayer conductance electronic transport twistronics

Series-based approximate approach of optimal tracking control for nonlinear systems with time-delay

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Progress in Natural science:Materials International 2008年第12期18卷 1571-1576页

作者： Gongyou Tang~a Mingqu Fan~(a,b) a college of information science and {3.,Ocean university of China,Qingdao 266100,China b college of information and {3.,Shandong university of science and technology,Jinan 25003.,China college of information science and {3. Ocean University of China Qingdao 266100 China college of information and engineering Shandong University of Science and Technology Jinan 250031 China

The optimal output tracking control (OTC) problem for nonlinear systems with time-delay is *** a series-based approx- imate approach,the original OTC problem is transformed into iteration solving linear two-point boundary value problems without time- *** OTC law obtained consists of analytical linear feedback and feedforward terms and a nonlinear compensation term with an infinite series of the adjoint *** truncating a finite sum of the adjoint vector series,an approximate optimal tracking control law is obtained.A reduced-order reference input observer is constructed to make the feedforward term physically *** exam- ples are used to test the validity of the series-based approximate approach.

关键词： Nonlinear systems Time-delay Tracking control Optimal control Observer

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science China(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2, LIU GuoQuan2, LI ZhiLin3. FENG ChengMing1 1 Mechanical and Electronic engineering college, Shandong Agricultural university, Tai’an 271018, China 2 college of Materials science and engineering, university of science and technology, Beijing 100083. China 3.college of Material science and engineering, Beijing university of Chemical technology, Beijing 100029, China Mechanical and Electronic engineering college Shandong Agricultural University Tai’an China college of Materials science and engineering University of Science and Technology Beijing China college of Material science and engineering Beijing University of Chemical Technology Beijing China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

Experimental study of interband and intraband crosstalk in WDM networks

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Optoelectronics Letters 2008年第1期4卷 42-44页

作者： GUAN Ai-hong and WANG Yu-hua college of information science and {3., henan university of technology, Zhengzhou 450001,China college of information science and {3. Henan University of Technology Zhengzhou China

The impacts of interband and intraband crosstalk are studied and compared experimentally. Results show that interband crosstalk can be removed with narrow-band filters and has no influence on signal. Intraband crosstalk will result in signal eye diagram close and BER increasing. When the polarization states of signal and crosstalk align, intraband crosstalk seriously decreases signal quality. But when they misalign, it has little influence. Coherent and incoherent crosstalk are studied experimentally. Results show that coherent crosstalk is less harmful to system performance than incoherent crosstalk.

关键词：光纤通信波长分组复用网络串话干扰实验研究

Approximately optimal tracking control for discrete time-delay systems with disturbances

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Progress in Natural science:Materials International 2008年第2期18卷 225-231页

作者： Gongyou Tang a,,Huiying Sun b,Haiping Pang c a college of information science and {3.,Ocean university of China,Qingdao 266100,China b college of information and Electrical {3.,Shandong university of science and technology,Qingdao 266510,China c college of Automation and Electronic {3.,Qingdao university of science and technology,Qingdao 266042,China college of information science and {3. Ocean University of China Qingdao 266100 China college of information and Electrical engineering Shandong University of Science and Technology Qingdao 266510 China college of Automation and Electronic engineering Qingdao University of Science and Technology Qingdao 266042 China

Optimal tracking control (OTC) for discrete time-delay systems affected by persistent disturbances with quadratic performance index is considered. By introducing a sensitivity parameter,the original OTC problem is transformed into a series of two-point boundary value (TPBV) problems without time-advance or time-delay terms. The obtained OTC law consists of analytic feedforward and feedback terms and a compensation term which is the sum of an infinite series of adjoint vectors. The analytic feedforward and feedback terms can be found by solving a Riccati matrix equation and two Stein matrix equations. The compensation term can be obtained by using an iteration formula of the adjoint vectors. Observers are constructed to make the approximate OTC law physically realizable. A simulation example shows that the approximate approach is effective in tracking the reference input and robust with respect to exogenous persistent disturbances.

关键词： Discrete systems Time-delay systems Disturbances Optimal control Tracking control

Sliding Mode Control with Disturbance Observer for a Class of Nonlinear Systems

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International Journal of Automation and computing 2012年第5期9卷 487-491页

作者： Lei-Po Liu Zhu-Mu Fu Xiao-Na Song college of Electric and information engineering, {3. university of science and technology, Luoyang 471003. China college of Electric and information engineering Henan University of Science and Technology Luoyang China

This paper is concerned with the stabilization problem for a class of nonlinear systems with disturbance. The disturbance model is unknown and the first derivative of disturbance is bounded. Firstly, a general disturbance observer is proposed to estimate disturbance approximatively. Secondly, since the bound of the disturbance observer error is unknown, an adaptive sliding mode controller is designed to guarantee that the state of system asymptotically converges to zero and the unknown bound can be adjusted by an adaptive law. Finally, an example is given to illustrate the effectiveness of the proposed method.

关键词： Nonlinear systems disturbance observer adaptive sliding mode control derivative of disturbance asymptotic stability

System View of Product Data Management and Its Application

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武汉理工大学学报 2006年第S3期28卷 989-993页

作者： WU Feng XU Su college of information science and {3.,henan university of technology,Zhengzhou 450052,China, college of information science and {3. Henan University of TechnologyZhengzhou 450052China

A product data management system for a manufacturing enterprise is to make sure that the proper product data can be communicated to the right people at the right *** paper describes a system analysis paradigm for data analysis in a product data management(PDM)*** aspects of the paradigm,i.e.,function,structure and behavior are rep- *** use of the paradigm explains why so many kinds of objects are necessary in a commercial database matrix and what models are available for developing a PDM *** another result,a lot of models are derived from the analysis of product data system paradigm to model product data and PDM database definitions.

关键词： product data management(PDM) system analysis product database paradigm

Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science China(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2, LIU Ping2, DONG Qiming2 & LI Hejun1 1. college of Materials science and engineering, Northwestern Polytechnical {3., Xi’an 710072, China 2. college of Materials science and engineering, henan {3. of science and technology, Luoyang 471003. China college of Materials science and engineering Northwestern Polytechnical University Xi’an China college of Materials science and engineering Henan University of Science and Technology Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.