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Progress in Natural science:materials International 2008年第3期18卷 331-336页

作者： Baolin Sun a,c, Shangchao Pi b, Chao Gui a, Yue Zeng d, Bing Yan a, Wenxiang Wang c, Qianqing Qin c a School of Computing, Hubei university of Economics, Wuhan 430205, china b College of science, Zhongyuan university of technology, Zhengzhou 450007, china c State key laboratory of information Engineering in Surveying, Mapping & Remote Sensing, Wuhan university, Wuhan 430079, china d Department of Computing, Jiangxi Vocational College of Finance and Economics, Jiangxi 332000, china School of Computing Hubei University of Economics Wuhan 430205 China State key laboratory of information Engineering in Surveying Mapping & Remote Sensing Wuhan University Wuhan 430079 China College of science Zhongyuan University of Technology Zhengzhou 450007 China Department of Computing Jiangxi Vocational College of Finance and Economics Jiangxi 332000 China

Usually multiple quality of service (QoS) guarantees are required in most multicast applications. This paper presents a multiple con-straints algorithm for multicast traffic engineering in mobile ad hoc networks (MANET). The proposed algorithm is a new version of multiple constraints QoS multicast routing optimization algorithm in MANET based on genetic algorithm (MQMGA). The proposed MQMGA can optimize the maximum link utilization, the cost of the multicast tree, the selection of the long-life path, the average delay and the maximum end-to-end delay. Experimental result shows that the approach is efficient, has promising performance in multicast traffic engineering and for evaluating the route stability in dynamic mobile networks.

关键词： Ad hoc network Multicast routing QoS Genetic algorithm

Immunodominance and clonal selection inspired multiobjective clustering

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Progress in Natural science:materials International 2009年第6期19卷 751-758页

作者： Wenping Ma , Licheng Jiao, Maoguo Gong key laboratory of Intelligent Perception and Image Understanding of the Ministry of Education of china, Institute of Intelligent information Processing, Xidian university, Xi’an 710071, china key laboratory of Intelligent Perception and Image Understanding of the Ministry of Education of china Institute of Intelligent Information Processing Xidian University Xi’an 710071 China

The biological immune system is a highly parallel and distributed adaptive system. The information processing abilities of the immune system provide important insights into the field of computation. Based on immunodominance in the biological immune system and the clonal selection mechanism, a novel data mining method, Immune Dominance Clonal Multiobjective Clustering algorithm (IDCMC), is presented. The algorithm divides an individual population into three sub-populations according to three different measurements, and adopts different evolution and selection strategies for each sub-population. The update of each sub-population, however, is not carried out in isolation. The periodic combination operation of the analysis of the three sub-populations represents considerable advantages in its global search ability. The clustering task is a multiobjective optimization problem, which is more robust with respect to the variety of cluster structures of different datasets than a single-objective clustering algorithm. In addition, the new algorithm can determine the number of clusters automatically, which should identify the most promising clustering solutions in the candidate set. The experimental results, using artificial datasets with different manifold structure and handwritten digit datasets, show that the IDCMC outperforms the PESA-Ⅱ-based clustering method, the genetic algorithm-based clustering technique and the original K-Means algorithm in solving most of the problems tested.

关键词： Artificial immune systems Multiobjective optimization Clustering Unsupervised learning

Moment tensor analysis of the acoustic emission source in the rock damage process

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Progress in Natural science:materials International 2005年第7期15卷 609-613页

作者： YU Huaizhong, ZHU Qingyong, YIN Xiangchu and WANG Yucang ( State key laboratory of Earthquake Dynamics, Institute of Geology, china Earthquake Administration, Beijing 100029, china State key laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of sciences, Beijing 100080, china School of Mathematics and Computational science, Zhongshan university, Guangzhou 510275, china Center for Analysis and Prediction, china Seismological Bureau, Beijing 100036, china Quakes, Department of Earth science, university of Queensland, Brishbane, Austrialia) State key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China State key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China School of Mathematics and Computational science Zhongshan University Guangzhou 510275 China Center for Analysis and Prediction China Seismological Bureau Beijing 100036 China Quakes Department of Earth Science University of Queensland Brishbane Australia

To further investigate the mechanism of acoustic emission (AE) in the rock fracture experiment, moment tensor analysis was carried out. The AE sources characterized by crack sizes, orientations and fracture modes, are represented by a time-dependent moment tensor. Since the waveforms recorded by AE monitors correlate to the moment tensors, we prefer to select the P wave amplitude from the full-space Green's function of homogeneous and isotropic materials to determine the six independent components of the moment tensor. The moment tensor analysis was used to investigate the AE sources recorded in the experiment, and three types of micro-cracks were found, which are tensile mode, shear mode and mixture of the tensile and shear mode. In addition, the motion of micro-cracks was decided by eigenvectors of moment tensor. Results indicate that the moment tensor analysis may be used as a measurement to reflect the damage evolution of rock specimen.

关键词： moment tensor acoustic emission rock fracture.

Particle swarm optimization with a leader and followers

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Progress in Natural science:materials International 2008年第11期18卷 1437-1443页

作者： Junwei Wang Dingwei Wang Institute of Systems Engineering,College of information science and Engineering,Northeastern university,Shenyang 110004,china Institute of Systems Engineering College of Information Science and Engineering Northeastern University Shenyang 110004 China

Referring to the flight mechanism of wild goose flock,we propose a novel version of Particle Swarm Optimization(PSO)with a leader and *** is referred to as Goose Team Optimization(GTO).The basic features of goose team flight such as goose role division, parallel principle,aggregate principle and separate principle are implemented in the recommended *** GTO,a team is formed by the particles with a leader and some *** role of the leader is to determine the search *** followers decide their flying modes according to their distances to the leader ***,a wide area can be explored and the particle collision can be really *** GTO is applied to four benchmark examples of complex nonlinear functions,it has a better computation perfor- mance than the standard PSO.

关键词： Particle swarm optimization Goose team optimization Role division Parallel principle Aggregate principle Separate principle

A new simulated annealing method of designing NMR biplanar shim coils

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Progress in Natural science:materials International 2006年第7期16卷 747-752页

作者： QI Feng, TANG Xin, WANG Weimin, SHEN Yifei, LIU Shaopo and JIANG Zhongde ( key laboratory for Quantum information and Measurements of Ministry of Education, School of Electronics Engineering & Computer science, Peking university, Beijing 100871, china Institute of Heavy Ion Physics, and Beijing key laboratory of Medical Physics and Engineering, Physical School, Peking university, Beijing 100871, china) Peking Univ Sch Elect Engn & Comp Sci Minist Educ Key Lab Quantum Informat & Measurements Beijing 100871 Peoples R China Peking Univ Sch Phys Beijing Key Lab Med Phys & Engn Beijing 100871 Peoples R China Peking Univ Inst Heavy Ion Phys Beijing 100871 Peoples R China

A new SA (simulated annealing) method is presented for the design of longitudinal shim coils for NMR (nuclear magnetic resonance) equipment. First, AGL (adaptive Gauss-Lobatto) quadrature used by the traditional SA method is analyzed. Two kinds of complete elliptic integrals are introduced to integrate the spatial magnetic field, which increases the computing speed by 13. 3 times. Then, the system energy calculation is extended to the field of the z-axis. The results illustrate that the coil-set efficiency designed by the new SA method is 15 % higher than that of the traditional one, and the field inhomogeneity is reduced from 1.20 % to 0.49 % . Finally, a prototype of coil assembly for NMR rock-core analyzer is built, and the experimental results are in good agreement with the theoretically calculated results.

关键词： NMR shim coil design simulated-annealing method complete elliptic integral.

A statistical model for porous structure of rocks

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science china(Technological sciences) 2008年第11期51卷 2040-2058页

作者： JU Yang1,2, YANG YongMing1, SONG ZhenDuo3 & XU WenJing4 1 State key laboratory of Coal Resources and Safe Mining, china university of Mining & technology, Beijing 100083, china 2 Department of Mechanical and Manufacturing Engineering, The university of Calgary, 2500 university Drive NW Calgary, AB T2N 1N4, Canada 3 china National Coal Mining Equipment Co. Ltd, Beijing 100011, china 4 Department of materials and Metallurgy, The university of Utah, Salt Lake City, Utah 84112, USA State key laboratory of Coal Resources and Safe Mining China University of Mining & Technology Beijing China Department of Mechanical and Manufacturing Engineering The University of Calgary Calgary Canada china National Coal Mining Equipment Co. Ltd Beijing China Department of materials and Metallurgy The University of Utah Utah USA

The geometric features and the distribution properties of pores in rocks were in- vestigated by means of CT scanning tests of sandstones. The centroidal coordi- nates of pores, the statistic characterristics of pore distance, quantity, size and their probability density functions were formulated in this paper. The Monte Carlo method and the random number generating algorithm were employed to generate two series of random numbers with the desired statistic characteristics and prob- ability density functions upon which the random distribution of pore position, dis- tance and quantity were determined. A three-dimensional porous structural model of sandstone was constructed based on the FLAC3D program and the information of the pore position and distribution that the series of random numbers defined. On the basis of modelling, the Brazil split tests of rock discs were carried out to ex- amine the stress distribution, the pattern of element failure and the inosculation of failed elements. The simulation indicated that the proposed model was consistent with the realistic porous structure of rock in terms of their statistic properties of pores and geometric similarity. The built-up model disclosed the influence of pores on the stress distribution, failure mode of material elements and the inosculation of failed elements.

关键词： porous structure statistical model random numbers reconstruction rocks

Photorefractivity in a Bi-functional Polymer Nanocomposites Sensitized by CdS Nanoparticle

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Journal of Wuhan university of technology(materials science) 2010年第4期25卷 550-554页

作者：丁莉芸 key laboratory of Fiber Optic Sensing technology and information Processing Ministry of Education Wuhan University of Technology

We report an organic/inorganic hybridized nanocomposite consisting of a bi-functional poly（N-vinyl）-3-[p-nitrophenylazo]carbazolyl serves as a polymeric charge-transporting and second-order nonliner optical matrix, and CdS nanoparticles as photosensitizers to manifest photorefractive （PR） effect. The unpoled PVNPAK film exhibits a second harmonic generation （SHG） coefficient of 4.7 pm/V due to the possibility of self-alignment of the azo chromophore. Significant enhancement of photoconductivity is noticed with the increase of CdS nanoparticles concentration. The photorefractive property of the polymer nanocomposites were determined by two-beam coupling （TBC） experiment. The TBC gain and diffraction efficiency of 11.89 cm-1 and 3.2% were obtained for PVNPAK/CdS at zero electrical field.

关键词： organic/inorganic hybridized bi-functional polymer photorefractive effect CdS nanoparticles

Magnetic,magetostrictive properties,spin reorientation and Mssbauer effect of Tb_(0.3)Dy_(0.7-x)Prx(Fe_(0.9)Al_(0.1))_(1.95) alloys

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science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 52-57页

作者： ZHENG XiaoPing1,2, ZHANG PeiFeng2,3, FAN DuoWang3 & LI FaShen3 1 Institute of Electronic information science and technology, Lanzhou City university, Lanzhou 730070, china 2 key laboratory of Opto-Electronic technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong university, Lanzhou 730070, china 3 key laboratory for Magnetism and Magnetic materials, Ministry of Education, Lanzhou university, Lanzhou 730000, china 1. Institute of Electronic information science and technology Lanzhou City University Lanzhou 730070 China 2. key laboratory of Opto-Electronic technology and Intelligent Control Ministry of Education Lanzhou Jiaotong University Lanzhou 730070 China 3. key laboratory for Magnetism and Magnetic materials Ministry of Education Lanzhou University Lanzhou 730000 China

The effect of Pr substitution for Dy on the magnetic and magnetostrictive properties, anisotropy, spin reorientation and Mssbauer effect of a series of Tb0.3Dy0.7-xPrx(Fe0.9Al0.1)1.95 (x=0,0.1,0.20,0.25,0.30,0.35) alloys at room temperature have been investigated. It was found that a small amount of Pr substitution is beneficial to a decrease in the magnetocrystalline anisotropy for the Tb0.3Dy0.7-xPrx(Fe0.9Al0.1)1.95 alloys. The magnetostriction decreases drastically with increasing x and the magnetostrictive effect disappears for x>0.2. However, the magnetostriction exhibits a slightly bigger value at x=0.1 than the free alloys and is saturated more easily with the magnetic field H. The saturation magnetization and Curie temperature decrease monotonously, but the spontaneous magnetostriction increases linearly with increasing x, whereas the spin reorientation temperature increases first, then decreases rapidly and reaches the maximum at x=0.1. The analysis of Mssbauer spectra indicated that the easy magnetization direction in the {110} plane deviates slightly from the main axis of symmetry with the Pr concentration x, namely spin reorientation. Compared with Al substitution for Fe, the effect of Pr substitution for Dy on spin reorientation is relatively small. The hyperfine field increases with Pr concentration increasing, and the isomer shifts and the quadrupole splitting (QS) show weak concentration dependence.

关键词： magnetostriction anisotropy spin reorientation Mssbauer

Crystallization of Fe_(78)Si_9B_(13) Bulk Crystaline/ Amorphous(c/a) Composite

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Journal of Wuhan university of technology(materials science) 2008年第5期23卷 595-599页

作者：金士锋王伟民 The key laboratory of Liquid Structure and Heredity of materials Shandong University (south campus) State key Lab of Metastable materials science and technology Yanshan University

A metallic crystalline/amorphous （c/a） bulk composite was prepared by the slow cooling method after remelting the amorphous Fe78Si9B13 ribbon. By X-ray diffraction （XRD）, differential scanning calorimetry （DSC） and scanning electron microscope （SEM）, the composite consists of the primary dendrite α-Ee （without Si） as well as the amorphous matrix. After being anneal at 800 K, the uniform spheroid particles are formed in the c/a composite, which does not form in the amorphous ribbon under the various annealing process. Energy dispersive analysis of X-rays （EDAX）, SEM and XRD were applied to give more detailed information. The formation and evolution of the particle may stimulate the possible application of the Fe-matrix amorphous alloy.

关键词： crystalline/amorphous composite Fe-Si-B crystallization