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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 university, Xi’an 710072.{2. 2. College of Materials science and Engineering, Henan university of science and technology, Luoyang 471003,{2. 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.

A novel DNA computing model based on RecA-mediated triple-stranded DNA structure

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Progress in Natural science:Materials International 2007年第6期17卷 708-711页

作者： Fang Gang1, Zhang Shemin2. Dong Yafei1 and Xu Jin1(1. The Key Laboratory of Image Processing and Intelligent Control, Department of Control science & Engineering, huazhong {2. of science and technology, Wuhan 430074, china 2. Shaanxi {2. of technology, Hanzhong 72.000, china) The Key Laboratory of Image Processing and Intelligent Control Department of Control Science & Engineering Huazhong University of Science and Technology Wuhan 430074 China Shaanxi university of technology Hanzhong 723000 China

The field of DNA computing emerged in 1994 after Adleman’s paper was published. Henceforth,a few scholars solved some noted NP-complete problems in this way. And all these methods of DNA computing are based on conventional Watson-Crick hydrogen bond of doublehelical DNA molecule. In this paper, we show that the triple-stranded DNA structure mediated by RecA protein can be used for solving computational problems. Sequence-specific recognition of double-stranded DNA by oligonucleotide-directed triple helix (triplex) formation is used to carry out the algorithm. We present procedure for the 3-vertex-colorability problems. In our proposed procedure, it is suggested that it is possible to solve more complicated problems with more variables by this model.

关键词： DNA computing 3-vertex-colorability problem.

Structure and Properties of BaFe_(12.O_(19) Coated Fly Ash Cenospheres by Sol-Gel Process

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Journal of Wuhan university of technology(Materials {2.) 2006年第3期21卷 129-131页

作者：曾爱香 Department of Materials science and technology Changsha University of Science and TechnologyChangsha 410076ChinaState Kay Laboratry of Die and Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

Thin films of barium hexaferrite were prepared on fly ash cenosphere particles by the sol-gel method using Fe（ NO3 ）3 ·9H2., Ba（ NO3 ）2.and citric acid as raw materials. The prepared films were characterized by differential thermal and thermogravimetric analysis （DTA-TG）, X-ray diffraction analysis （XRD）, scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDX）, X-ray photoelectron spectroscopy （XPS）, and vibrating sample magnetometry . The magnetic and structural properties of barium hexaferrite coated cenosphere particles were also studied. The experimental results show that even and continual barium hexaferrite coatings were prepared on fly ash cenospheres , and the magnetic conductivity was imparted to these non-conducting oxide ceramic particles. The low density barium hexaferrite coated cenosphere particles may be atilized for manufacturing microwave absorbing materials.

关键词： barium hexaferrite coating fly ash cenosphere particles sol-gel

Structure and kinematic analysis of a novel 2.DOF translational parallel robot

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Progress in Natural science:Materials International 2007年第10期17卷 1213-1219页

作者： Chen Tao1, Wu Chao2.and Liu Xinjun2.1. School of Application science and technology, Harbin {2. of science and technology, Harbin 150080, china 2. Department of Precision Instruments, Tsinghua {2., Beijing 100084, china) School of Application science and technology Harbin University of Science and Technology Harbin 150080 China Department of Precision Instruments Tsinghua University Beijing 100084 China

This paper addresses the analysis of a novel parallel robot with 2.translational degrees of freedom (DOFs). The robot can position a rigid body in a plane with constant orientation. The kinematic structure of the robot is first described in detail. Some kinematic problems, such as the inverse and forward kinematics, velocity, and singularity are then analyzed. The working and assembly modes are discussed. Since it is the most important index to design a robot, the workspace of the robot is studied systematically in this paper. Based on the analysis of reachable workspace and singularity, a kind of workspace concept characterizing the region that the end-effector of the robot can reach in practice is defined. The results of this paper will be very useful for the design and application of the robot.

关键词： parallel robot degree of freedom kinematics workspace.

Structure and Magnetic Properties of Ni-doped ZnO Powder

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Journal of Wuhan university of technology(Materials {2.) 2010年第5期25卷 770-773页

作者：高放赵俊 Department of Electronic science and technology Huazhong University of Science and Technology

Ni-doped ZnO nanopowder （Zn0.98Ni0.2.） was synthesized by improved coprecipitation method. The average particle size of the powder was estimated to be 50 nm. The powder was then processed by thermal treatment. Samples were annealed at 1 073, 1 2.3, and 1 473 K, respectively. The solubility of NiO in ZnO and the lattice parameters of ZnO both increased with the temperature. The magnetic property of the doped samples was examined, and hysteresis loops were got. The results showed all the samples were ferromagnetic, while powder processed at 1 2.3 K for 4 h got a highest saturation magnetization （Ms） of 0.0457 emu/g. Also, magnetic properties were related to the grain size of the powder.

关键词： ferromagnetism diluted magnetic semiconductor Ni-doped ZnO coprecipitation solid state reaction

Uniform estimate for maximum of randomly weighted sums with applications to insurance risk theory

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science china Mathematics 2005年第10期48卷 1379-1394页

作者： WANG Dingcheng~1 SU Chun~2.& ZENG Yong~1 1. School of Management and School of Applied Mathematics,university of Electronic science and {2. of china,Chengdu 610054,china 2. Department of Statistics and Finance,university of science and {2. of china,Hefei 2.002.,china School of Management and School of Applied Mathematics University of Electronic Science and Technology of China Chengdu China Department of Statistics and Finance University of Science and Technology of China Hefei China

This paper obtains the uniform estimate for maximum of sums of independent and heavy-tailed random variables with nonnegative random weights, which can be arbitrarily dependent of each other. Then the applications to ... 详细信息

关键词： dependent stochastic return, discount factor, heavy-tails, discrete time insurance risk model, maxima of randomly weighted sums, ruin probability, tail probabilities, uniformly asymptotic estimate.

Real estate appraisal system based on GIS and BP neural network

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中国有色金属学会会刊：英文版 2011年第S3期21卷 626-630页

作者： LIU Xiao-sheng1, DENG Zhe1, WANG Ting-li2.1. School of Architecture and Survey Engineering, Jiangxi university of science and {2., Ganzhou 341000, china 2. School of Applied science, Jiangxi university of science and {2., Ganzhou 341000, china School of Architecture and Survey Engineering Jiangxi University of Science and Technology Ganzhou 341000 China School of Applied science Jiangxi University of Science and Technology Ganzhou 341000 China

For the inefficiency and inaccuracy of appraisal method of traditional estate appraisal theory, the real estate appraisal system based on GIS and BP neural network was established. The structure of the system was designed which includes appraisal model, trade case, GIS database and query analysis module. With the help of the L-M algorithm in MATLAB software, BP neural network was improved and the trade cases were trained, then the BP neural network which has already been trained was tested. At the same time, the BP neural and GIS were put together to construct the hedonic price estimate model. The C# and ArcGIS9.3 were used to achieve the system in VS2.08. City basic geographic data and real estate related information were used as the basic data in practice. The results show that the functions of querying, adding and editing the spatial data and attribute data are achieved and also the efficiency and accuracy of real estate are improved, so that the new method of real estate is provided by the system.

关键词： BP neural network GIS hedonic price real estate appraisal

Biological networks to the analysis of microarray data

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Progress in Natural science:Materials International 2006年第12期16卷 1242-1251页

作者： FANG Zhuo~1, LUO Qingming~1**, ZHANG Guoqing~1 and LI Yixue~2.*(1. Hubei Bioinformatics and Molecular Imaging Key Laboratory,huazhong university of {2. and technology, Wuhan 430074, china 2. Shanghai Center for Bioinformation and technology, Shanghai 2.02.5, china) Hubei Bioinformatics and Molecular Imaging Key Laboratory Huazhong University of Science and Technology Wuhan 430074 China Shanghai Center for Bioinformation and technology Shanghai 200235 China

Microarray technology, which permits rapid and large-scale screening for patterns of gene expressions, usually generates a large amount of data. How to mine the biological meanings under these data is one of the main challenges in bioinformatics. Compared to the pure mathematical techniques, those methods incorporated with some prior biological knowledge generally bring better interpretations. Recently, a new analysis, in which the knowledge of biological networks such as metabolic network and protein interaction network is introduced, is widely applied to microarray data analysis. The microarray data analysis based on biological networks contains two main research aspects: identification of active components in biological networks and assessment of gene sets significance. In this paper, we briefly review the progress of these two categories of analyses, especially some representative methods.

关键词： biological networks microarray data analysis subnetwork gene set.

The optimization of DNA encodings based on GA/SA algorithms

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Progress in Natural science:Materials International 2007年第6期17卷 739-744页

作者： Wang Wei1, Zheng Xuedong2. Zhang Qiang1 and Xu Jin2.1. Liaoning Key Laboratory of Intelligent Information Processing, Dalian university, Dalian 11662., china 2. Department of Control {2. and Engineering, huazhong university of {2. and technology, Wuhan 430074, china) Liaoning Key Laboratory of Intelligent Information Processing Dalian University Dalian 116622 China Department of Control science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

The design of DNA sequence plays an important role in improving the reliability of DNA computation. Proper constrained terms that DNA sequence should satisfy are selected, and then the evaluation formulas of each DNA individual corresponding to the selected constrained terms are proposed. The heuristic improved genetic algorithm (GA)/simulated annealing (SA) algorithm is presented to solve the multi-objective optimize problem, and the DNA sequence design system is developed. Furthermore, an example is illustrated to show the efficiency of our method given here.

关键词： DNA encoding multi-objective optimize GA/SA algorithms