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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. 1. College of Materials Science and engineering Northwestern Polytechnical University 710072 Xi’an China 2. College of Materials Science and engineering Henan University of Science and Technology 471003 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 new orthogonality relationship for orthotropic thin plate theory and its variational principle

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 371-380页

作者： LUO Jianhui 1 , LONG Yuqiu 2.& LIU Guangdong 1 1. College of Civil engineering, Hunan university, Changsha 410082.{2. 2. Department of Civil engineering, Tsinghua university, Beijing 100084,{2. 1. College of Civil engineering Hunan University 410082 Changsha China 2. Department of Civil engineering Tsinghua University 100084 Beijing China

The thought how dual vectors are constructed in a new orthogonality relationship for theory of elasticity is generalized into orthotropic thin plate bending problems by using the analogy theory between plane elasticity problems and plate bending problems. Dual differential equations are directly obtained by using a mixed variables method. A dual differential matrix to be derived possesses a peculiarity of which principal diagonal sub-matrixes are zero matrixes. Two independently and symmetrically orthogonality sub-relationships are discovered. By using the integral form for elastic bending theory of orthotropic thin plate the orthogonality relationship is demonstrated. By selecting felicitous dual vectors a new orthogonality relationship for theory of elasticity can be generalized into elastic bending theory of orthotropic thin plate. By using the integral form a variational principle which is relative to differential form and a whole function expression are proposed.

关键词： theory of elasticity, thin plate theory, dual vectors, orthogonality relationship, orthotropic, variational principle.

Controlled Size and Density Distribution of Nanoparticles by Thermal Ammonia Etching Method

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Journal of Wuhan university of Technology(Materials Science) 2010年第1期25卷 108-111页

作者：李刚 Key Laboratory of Ministry of Education for Conveyance and Equipment East China Jiaotong University Center for Photon Fabrication Science and Technology Jiangsu University

Nickel nanometer catalyst thin films were prepared on SiO2.Si substrates using sputtering coater. The effects of ammonia pretreatment on the catalyst films from continuous film to the nanoparticles were investigated. The nanostructures of the Ni thin films as a function of the catalyst film original thickness, the pretreatment time and temperature were discussed. The optimum parameters of etching process were obtained, and the functional mechanism of ammonia was primarily analyzed. Scanning electron microscopy （SEM） and atomic force microscopy （AFM） were used to evaluate the obtained nanoparticles. It is demonstrated that the controlled size and density distribution of the nanoparticles can be achieved by employing ammonia etching method.

关键词： ammonia etching nanoparticle density control thermal expansion

A novel algorithm of artificial immune system for high-dimensional function numerical optimization

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Progress in Natural Science:Materials International 2005年第5期15卷 463-471页

作者： DU Haifeng 1,2.*, GONG Maoguo1, JIAO Licheng1 and LIU Ruochen1(1. Institute of Intelligent Information Processing and Key Laboratory of Radar Signal Processing, Xidian university, Xi'an 710071, china 2. {2. of Mechanical engineering, Xi'an Jiaotong university, Xi'an 710049, china) Institute of Intelligent Information Processing and Key Laboratory of Radar Signal Processing Xidian University Xi''an 710071 China school of Mechanical engineering Xi''an Jiaotong University Xi''an 710049 China

Based on the clonal selection theory and immune memory theory, a novel artificial immune system algorithm, immune memory clonal programming algorithm (IMCPA), is put forward. Using the theorem of Markov chain, it is proved that IMCPA is convergent. Compared with some other evolutionary programming algorithms (like Breeder genetic algorithm), IMCPA is shown to be an evolutionary strategy capable of solving complex machine learning tasks, like high-dimensional function optimization, which maintains the diversity of the population and avoids prematurity to some extent, and has a higher convergence speed.

关键词： clonal selection immune memory artificial immune system evolutionary algorithms Markov chain.

A SEMI-ANALYTICAL SOLUTION FOR CHARACTERISTICS OF A DAMRESERVOIR SYSTEM WITH ABSORPTIVE RESERVOIR BOTTOM

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Journal of Hydrodynamics 2008年第6期20卷 727-734页

作者： LI Shang-ming LIANG Hong LI Ai-min school of Civil engineering and Architecture Nanchang University Nanchang 330031 China

In this study, a semi-analytical formulation based on the Scaled Boundary Finite Element Method （SBFEM） was proposed and used to obtain the solution for the characteristics of a two-dimensional dam-reservoir system with absorptive reservoir bottom in the frequency domain. For simplicity, the dam with arbitrary upstream faces was assumed to be rigid and was subjected to a horizontal ground acceleration, while the reservoir with absorptive bottom was assumed to be semi-infinite. The reservoir was divided into two sub-domains： a near-field sub-domain and a far-field sub-domain. The near-field sub-domain with arbitrary geometry was modelled by the Finite Element Method （FEM）, while the effects of the far-field sub-domain which was assumed to be horizontal were described by a semi-analytical formation. The semi-analytical formulation involved the effect of absorptive reservoir bottom, as well as the radiation damping effect of a semi-infinite reservoir. A FEM/SBFEM coupling formulation was presented to solve dam-reservoir coupled problems. The accuracy and efficiency of the coupling formulation were demonstrated by computing some benchmark examples. Highly accurate results are produced even if the near-field sub-domain is very small.

关键词： dam-reservoir interaction absorptive bottom SBFEM Hydraulic pressure FEM/SBFEM coupling formulation

Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1, 2. ZHANG Yin-ling1, 2. WANG Fei 1 ,2. ZHANG Zhen-hui 3, GUO Yu-xiang1, 2.1. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003, china 2. {2. of Surveying and land Information engineering, Henan Polytechnic university, Jiaozuo 454003, china 3. Qingdao Branch of Naval Aeronautical engineering Institute, Qingdao 2.6041, china Henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China Henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

A self-selecting memory element based on a method of interconnected ovonic threshold switching device

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Science china(Information Sciences) 2024年第3期67卷 319-320页

作者： Jinyu WEN Lun WANG jiangxi CHEN Hao TONG Xiangshui MIAO school of Integrated Circuits Huazhong University of Science & Technology Institute of Artificial Intelligence Huazhong University of Science & Technology Hubei Yangtze Memory Laboratories

Currently, the 3-D cross-point structure has been successfully applied in phase change memory(PCM) to achieve scalable and stackable memory arrays [1]. The ovonic threshold switching(OTS) selector consists of a memory element that is used to suppress the parasitic current in the 3-D cross-point arrays due to its highly nonlinear currentvoltage(I-V)characteristics which are significant for largescale memory arrays [2..

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Effect of Nd_2.e_(14)B/α-Fe Nanocomposite Permanent Magnets with a Combined Co and Nb Additions

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Journal of Wuhan university of Technology(Materials Science) 2009年第5期24卷 725-727页

作者：马瑞 school of Materials Science and Metallurgy engineering Guizhou University

Influence of Co＋Nb on the Nd8Fe82.o3Nb1B6 nanocomposite magnets was investigated by adding Co element combined with Nb element. Results show that the high temperature stability of two phases is increased. Adding Co＋Nb could improve the glass forming ability of the alloy, reduce the size of grains, increase the exchange coupling ability of two phases, and obviously increase the magnetic properties of the alloy. The optimal magnetic properties are Br=1.14 T, Hcj=32. kA/m, （BH）max=109.3 kJ/m^3

关键词： nanocomposite permanent magnets glass forming ability exchange coupling ability magnetic properties

Phosphorus forms and distribution in the sediments of Poyang Lake,china

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International Journal of Sediment Research 2011年第2期26卷 230-238页

作者： XIANG Su-lin and ZHOU Wen-bin 1 Lecturer,Key Lab of Poyang Lake Ecology and Bio-resource Utilization,Ministry of Education,nanchang university,nanchang 330047,china and Department of Environmental engineering,East china JiaoTong university,nanchang 330013,china, 2.Prof,Key Lab of Poyang Lake Ecology and Bio-resource Utilization,Ministry of Education,nanchang university,nanchang 330047,china [a]Lecturer Key Lab of Poyang Lake Ecology and Bio-resource Utilization Ministry of Education Nanchang University Nanchang 330047 China and Department of Environmental Engineering East China JiaoTong University Nanchang 330013 China [b]Prof. Key Lab of Poyang Lake Ecology and Bio-resource Utilization Ministry of Education Nanchang University Nanchang 330047 China

The forms and distribution of phosphorus in the sediments of Poyang Lake were studied using chemical extraction methods to understand the potential release and adsorption of *** results showed that phosphorus in the sediments mainly consisted of inorganic phosphorous species, including iron bound phosphorus,calcium bound phosphorus,aluminium bound phosphorus and dissolved phosphorus,as well as organic phosphorous *** spatial distribution of phosphorus species in surface sediments showed a decreasing trend from the outlet to the entrance of Poyang *** content of total phosphorus in the surface sediments ranged from 688.2. to 82..36 mg/kg, and inorganic phosphorous was the major phosphorus *** bound phosphorus was the dominant form of inorganic phosphorous,accounting for greater than 40%of the total phosphorus, while calcium bound phosphorus and aluminium bound phosphorus accounted for more than 2.%, and dissolved phosphorus accounted for less than 5%.The content of organic phosphorus in surface sediments was lower,accounting for less than 15%.Total phosphorus was positively correlated with iron bound phosphorus,aluminium bound phosphorus,calcium bound phosphorus and organic phosphorous,while organic phosphorous was positively correlated with iron bound phosphorus and aluminium bound phosphorus,but only weakly related to calcium bound *** all six sites, the contents of total phosphorus and phosphorus forms in the core sediments obviously decreased with depth,while they were significantly enriched in the surface *** total phosphorus and phosphorus forms contents were significantly higher in the upper layers and had a tendency to decrease toward the bottom of the core,regardless of the phosphorus *** addition,the average contents of total phosphorus and various phosphorus forms decreased rapidly with sediment depth from 0-2. cm,and then decreased slightly from 2.-30 cm.

关键词： Poyang Lake Phosphorus forms Distribution characteristics Sediment

The GPS-gravimetry boundary value problem

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Science china Earth Sciences 2005年第3期48卷 398-405页

作者： YU Jinhai1,2.& ZHANG Chuanding2.1. Institute of Geodesy and Geophysics of Chinese Academy of Sciences, Wuhan 430077, china 2. Zhengzhou Information engineering {2., Zhengzhou 450052. china 1. Institute of Geodesy and Geophysics of Chinese Academy of Sciences 430077 Wuhan China 2. Zhengzhou Information engineering university 450052 Zhengzhou China

How to determine the earth’s external gravity field with the accuracy of O(T2. by making use of GPS data and gravity values measured on the earth’s surface is dealt with in this paper. There are two main steps: to extend these measured values on the earth’s surface onto the reference ellipsoid at first and then to seek for the integral solution of the external Neumann problem outside the ellipsoid. In addition, the corresponding judging criteria of accuracy to solve the GPS-gravity boundary value problem are established. The integral solution given in the paper not only contains all frequency-spectral information of the gravity field with the accuracy of O(T 2., but is also easily computed. In fact, the solution has great significance for both theory and prac- tice.

关键词： Neumann boundary value problem, integral solution, gravity disturbance.