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The effects of relative density of metal foams on the stresses and deformation of beam under bending

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Acta Mechanica Sinica 2007年第4期23卷 409-414页

作者： Aiyu Zhu Tianyou Fan Department of mathematics,school of {2.,Beijing Institute of technology,P.O.Box 32.,Beijing 100081,china Department of physics,school of {2.,Beijing Institute of technology,P.O.Box 32.,Beijing 100081,china Department of mathematics School of Science Beijing Institute of Technology Department of physics School of Science Beijing Institute of Technology

The exact analytic solution of the pure bending beam of metallic foams is given. The effects of relative density of the material on stresses and deformation are revealed with the Triantafillou and Gibson constitutive law （TG model） taken as the analysis basis. Several examples for individual foams are discussed, showing the importance of compressibility of the cellular materials. One of the objects of this study is to generalize Hill＇s solution for incompressible plasticity to the case of compressible plasticity, and a kinematics parameter is brought into the analysis so that the velocity field can be determined.

关键词： Metal foams - Relative density Compressible plasticity Constitutive law - TG model

Codes From Strongly Regular (α,β)-reguli

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Journal of Shanghai Jiaotong university(science) 2008年第4期13卷 491-494页

作者：李秀丽 Department of mathematics Shanghai Jiaotong University

Strongly regular (α,β)-reguli are a class of incidence structures with given conditions which were introduced by Hamilton and Mathon. We introduce two classes of codes constructed from strongly regular (α,β)-regul... 详细信息

关键词： two-weight codes strongly regular (α,β)-reguli

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

The feature study on the π and proton rapidity distributions at AGS, SPS and RHIC

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science china({2.,Mechanics & Astronomy) 2009年第2期52卷 198-206页

作者： FENG ShengQin1,2.& YUAN XianBao1,3 1 College of science, china Three Gorges University, Yichang 443002. china 2.school of physics and technology, Wuhan University, Wuhan 430072. china 3 Institute of Particle physics, Central china Normal University, Wuhan 430070, china College of science China Three Gorges University Yichang China school of physics and {2. Wuhan University Wuhan China Institute of Particle physics Central China Normal University Wuhan China

The features of nuclear stopping power and multi-hadron production systematically are studied by making an analysis of rapidity distributions of pion and proton at AGS, SPS and RHIC in this work. It is found that nuclear stopping power increases linearly with project rapidity yp at AGS and SPS, but that is not liner at RHIC. It is argued that the average rapidity loss is saturated at central rapidity region at RHIC. For pion distribution, it is found that the phase space of pion distribution distributes uniformly in the longitudinal direction,and a linear relationship of L with log s is given at AGS and SPS. Non-uniform flow model may explain the features of the distribution at AGS and SPS, but may not ex- plain those of at RHIC.

关键词： non-uniform flow model average rapidity loss baryon number density nuclear stopping power

On the new results of global attractive set and positive invariant set of the Lorenz chaotic system and the applications to chaos control and synchronization

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science in china(Series F) 2005年第3期48卷 304-321页

作者： LIAO Xiaoxin 1, 2. 3 , FU Yuli 4 & XIE Shengli 4 1. Department of Control science & Control Engineering, Huazhong University of science & {2., Wuhan 430074, china 2. school of Automation, Wuhan University of science & {2., Wuhan 430070, china 3. school of information, Central South University of Economy, Politics and Law, Wuhan 430064, china 4. school of Electronics & information Engineering, South china University of {2., Guangzhou 510640, china Correspondence should be addressed to Liao Xiaoxin (email: xiaoxin_liao@***) Department of Control science & Control Engineering Huazhong University of Science & Technology Wuhan 430074 China

Constructing a family of generalized Lyapunov functions, a new method is proposed to obtain new global attractive set and positive invariant set of the Lorenz chaotic system. The method we proposed greatly simplifies the complex proofs of the two famous estimations presented by the Russian scholar Leonov. Our uniform formula can derive a series of the new estimations. Employing the idea of intersection in set theory, we extract a new Leonov formula-like estimation from the family of the estimations. With our method and the new estimation, one can confirm that there are no equilibrium, periodic solutions, almost periodic motions, wandering motions or other chaotic attractors outside the global attractive set. The Lorenz butterfly-like singular attractors are located in the global attractive set only. This result is applied to the chaos control and chaos synchronization. Some feedback control laws are obtained to guarantee that all the trajectories of the Lorenz systems track a periodic solution, or globally stabilize an unstable (or locally stable but not globally asymptotically stable) equilibrium. Further, some new global exponential chaos synchronization results are presented. Our new method and the new results are expected to be applied in real secure communication systems.

关键词： Lorenz chaotic system global attractive set positive invariant set globally exponential tracking globally exponential synchronization.

Application of Diagonal Recurrent Neural Network toDC Motor Speed Control Systems

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 68-71页

作者： Jing Wang Hui Chen information Engineering school, University of {2. and technology Beijing, Beijing 100083, china information Engineering school University of Science and Technology Beijing Beijine 100083 China

A new kind of dynamic neural network--diagonal recurrent neural network (DRNN) and its learning method and architecture are presented. A direct adaptive control scheme is also developed that is applied to a DC (Direct Current) speed control system with the ability to auto-tune PI (Proportion Integral) parameters based on combining DRNN with PI controller. The simulation results of DRNN show better control performances and potential practical use in comparison with PI controller.

关键词： diagonal recurrent neural network PI controller DC Motor speed control system

Refractive index changes induced by sheet beams with various intensity distributions in LiNbO_(3):Fe crystal

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science china({2.,Mechanics & Astronomy) 2005年第4期48卷 399-412页

作者： ZHANG Peng1, ZHAO Jianlin1, XU Honglai1, SUN Yidong2. YANG Dexing1 & WANG Meirong1 1. Institute of Optical information science and {2., school of science, Northwestern Polytechnical University, Xi’an 710072. china 2. school of science, Xi’an Jiaotong University, Xi’an 710049, china Institute of Optical information science and Technology School of Science Northwestern Polytechnical University Xi’an China school of science Xi’an Jiaotong University Xi’an China

According to the Kukhtarev equations and a simplified model based on the photovoltaic charge carriers transport mechanism, the distributions of the index changes (DICs) in LiNbO3:Fe crystals induced by sheet beams with various intensity profiles are theoretically analyzed. The numerically simulated results coincide with the analytic expressions deduced from the simplified model. The DICs in a LiNbO3:Fe crystal induced by sheet beams with rectangular, Gaussian and square law profiles are measured by using the interferometric method. By employing the analytic expressions, the experimental data points are well fitted. By utilizing the angular spectrum theory and the ray equation, the uniformities of the intensity profiles of the writing beams along the propagation directions and the influences of the self-defocusing effect of the crystal are numerically simulated, respectively. The results show that the experimental results are reliable. The numerically simulated method and the analytic expressions can be both employed to predict the DICs induced by sheet beams with various light intensity profiles. Furthermore, utilizing writing beams with proper intensity profiles, any desired index distributions could be obtained.

关键词： LiNbO3:Fe crystal, light intensity profile, distribution of refractive index changes, sheet beam.

Focal plane wave-front sensing algorithm for high-contrast imaging

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science china({2.,Mechanics & Astronomy) 2009年第8期52卷 1284-1288页

作者： DOU JiangPei1,2.3,REN DeQing1,2.4,ZHU YongTian1,2.& ZHANG Xi1,2.3 1 National Astronomical Observatories/nanjing Institute of Astronomical Optics & technology,Chinese Academy of {2.s,nanjing 2.0042.china 2.Key Laboratory of Astronomical Optics & technology,nanjing Institute of Astronomical Optics & technology,Chinese Academy of {2.s,nanjing 2.0042.china 3 Graduate University of Chinese Academy of {2.s,Beijing 100049,china 4 physics & Astronomy Department,California State University Northridge,18111 Nordhoff Street,Northridge,California 91330-82.8,USA National Astronomical Observatories/nanjing Institute of Astronomical Optics & technology Chinese Academy of Sciences Nanjing China Key Laboratory of Astronomical Optics & technology Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing China Graduate University of Chinese Academy of sciences Beijing China physics & Astronomy Department California State University Northridge Northridge USA

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star.A major limitation for such direct imaging is the speckle noise that is induced from the wave-front error of an optical *** derive an algorithm for the wave-front measurement directly from 3 focal plane *** 3 images are achieved through a deformable mirror to provide specific phases for the optics *** introduce an extra amplitude modulation on one deformable mirror configuration to create an uncorrelated wave-front,which is a critical procedure for wave-front *** simulation shows that the reconstructed wave-front is consistent with the original wave-front theoretically,which indicates that such an algorithm is a promising technique for the wave-front measurement for the high-contrast imaging.

关键词： high-contrast imaging multi-image algorithm speckle nulling technique wave-front sensing

Analysis of the co-seismic responses of the fluid well pattern system in Jiangsu Province to the Wenchuan and Tohoku earthquakes

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Earthquake science 2012年第3期25卷 263-274页

作者： Jiangrong Zheng1, Haolin Jiang1 and Zhengran He2.1 Earthquake Administration of Jiangsu Province, nanjing 2.0014, china 2.{2. of information science and Engineering, Southeast University, nanjing 2.0049, china Earthquake Administration of Jiangsu Province Nanjing 210014 China

This thesis discusses the earthquake reflecting ability of the observation well pattern system of Jiangsu Province, china, which has been digitally renovated, and probes into the cause of the major differences in the earthquake reflecting abilities of well holes at different measurement points. This is achieved through the analysis of the co-seismic responses to the Wenchuan (2.08; Ms8.0, china) and Tohoku (2.11; Ms9.0, Japan) earthquakes. We found that the co-seismic response of water level from regional well holes in Jiangsu Province was stronger than that of water temperature. The water-level co-seismic response follows a consistent law and is closely related to the earthquake magnitude. The co-seismic response of water temperature strongly varied among well points, and was more often manifested as a slow restorative change. The co-seismic responses also varied based on tectonic elements. The response in central and northern Jiangsu was weaker than that of southern Jiangsu, possibly due to the thicker loess cover layer in central Jiangsu which makes it less effective at capturing the micro-changes of stress-strain states relative to the hilly land in the south. The more complicated geological structure in southern Jiangsu makes it contribute to greater changes in the state of underground water after a minor disturbance.

关键词： fluid well pattern system 2.08 Ms8.0 Wenchuan earthquake 2.11 MS9.0 Tohoku earthquake features of co-seismic responses