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Research and application of flood damage evaluation information system

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中国有色金属学会会刊：英文版 2005年第S1期15卷 204-207页

作者： SHI Jin-feng~1, WU Zhi-zhou~2. SONG Wei-dong~1 (1. Liaoning Technical university, Fuxin 12.000, china 2.{2., shanghai 2.0092. china) Liaoning Tech Univ Fuxing 123000 Peoples R China tongji Univ Shanghai 200092 Peoples R China

The fast evaluation method of flood damages was explored with the combination of high technologies, such as remote sensing (RS) and geographic information system (GIS), namely the land classification and extraction of flood areas were accomplished in RS image processing software, ENVI, the flood damages information system, digital terrain model and flood damages evaluation information system were developed on GIS platform GeoMedia. The problem of the combination of multi-source data was addressed, furthermore, the problems of how to build the flood damages evaluation model and the inundating elevation model were deeply probed, the calculating formulas were also given. Case study result shows that the evaluation models are correct and data are reliable, we can use it to evaluate real-time flood damages and provide evidences for decision-making of leaders, moreover, it is of great instructive significance to the research of flood damages evaluation theories.

关键词： flood damages GIS remote sensing digital terrain model evaluation

A NEW NUMERICAL METHOD FOR GROUNDWATER FIOW AND SOLUTE TRANSPORT USING VELOCITY FIELD

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Journal of Hydrodynamics 2008年第3期20卷 356-364页

作者： ZHANG Qian-fei LAN Shou-qi WANG Yan-ming XU Yong-fu School of Naval Architecture Ocean and Civil Engineering Shanghai Jiaotong University Shanghai 200030China shanghai Municipal Engineering Design institute Shanghai 200092 China Department of Geotechnical Engineering Tongji University Shanghai 200092 China

A new numerical method for groundwater flow analysis was introduced to estimate simultaneously velocity vectors and water pressure head. The method could be employed to handle the vertical flow under variably saturated conditions and for horizontal flow as well. The method allows for better estimation of velocities at the element nodes which can be used as direct input to transport models. The advection-dispersion process was treated by the Eulerian-Lagrangian approach with particle tracking technique using the velocities at FEM nodes. The method was verified with the classical one dimensional model and applied to simulate contaminant transport process through a slurry wall as a barrier to prevent leachate pollution from a sanitary landfill.

关键词： groundwater flow solute transport velocity vectors finite element method Eulerian-Lagrangian approach particletracking technique

Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

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Science china Earth Sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2. LI Xiubin2.& ZHANG Ming2.1. institute of Remote Sensing & GIS, Peking university, Beijing 100871, {2. 2. institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, {2. 1. institute of Remote Sensing & GIS Peking University 100871 Beijing China 2. institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 2.%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.

DFT study of the conductance of molecular wire:The effect of coupling geometry and intermolecular interaction on the transport properties

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Science china Chemistry 2006年第6期49卷 492-498页

作者： QI Yuanhua1,2. GUAN Daren1 & LIU Chengbu1 1. institute of Theoretical Chemistry, Shandong university, Jinan 2.0100, {2. 2. School of Physics and Microelectronics, Shandong university, Jinan 2.0061, {2. 1. institute of Theoretical Chemistry Shandong University Jinan 250100 China 2. School of Physics and Microelectronics Shandong University Jinan 250061 China

The density functional theory (DFT) combining with the non-equilibrium Green functions (NEGF) method is applied to the study of the electronic transport properties for a Di-thiol-benzene (DTB) molecule coupled to two Au(111) surfaces. The dependence of the transport properties on the bias, the coupling geometry of the molecule-electrode interface, and the intermolecular interaction are examined in detail. The results show that the existence of the hydrogen atom at the end of the DTB molecule would significantly decrease the transmission coefficients, and then the differential conductance (dI/dV). By changing the position of the DTB molecule located between two electrodes a maximum value of calculated current is observed. It is also found that the intermolecular interaction will strongly influence the transport properties of the system studied.

关键词： non-equilibrium Green functions method, transmission spectrum, the molecular projected selfconsistent Hamiltonian, projected density of state.

θ-PSO: a new strategy of particle swarm optimization

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2008年第6期9卷 786-790页

作者： Wei-min ZHONG1,2. Shao-jun LI1,2. Feng QIAN1,2.(1State Key Laboratory of Chemical Engineering, East china university of Science and Technology, {2. 2.02.7, china) (2.utomation institute, East china university of Science and Technology, {2. 2.02.7, china) State Key Laboratory of Chemical Engineering East China University of Science and Technology Shanghai China Automation institute East China University of Science and Technology Shanghai China

Particle swarm optimization (PSO) is an efficient, robust and simple optimization algorithm. Most studies are mainly concentrated on better understanding of the standard PSO control parameters, such as acceleration coefficients, etc. In this paper, a more simple strategy of PSO algorithm called θ-PSO is proposed. In θ-PSO, an increment of phase angle vector replaces the increment of velocity vector and the positions are decided by the mapping of phase angles. Benchmark testing of nonlinear func- tions is described and the results show that the performance of θ-PSO is much more effective than that of the standard PSO.

关键词： Particle swarm optimization (PSO) Phase angle Benchmark function

Different-Periodic Travelling Wave Solutions for Nonlinear Equations

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Communications in Theoretical Physics 2004年第4期41卷 481-486页

作者： YE Li-Jun~1 LIN Ji~(1,2.1 Department of Physics,Zhejiang Normal university,Jinhua 32.004,china2.Physics Department,{2. Jiao Tong university,{2. 2.0030,china Physics Department Shanghai Jiao Tong University Shanghai 200030 China

Using Jacobi elliptic function linear superposition approach for the(1+1)-dimensional Caudrey-Dodd-Gibbon-Sawada-Kotera(CDGSK)equation and the(2.1)-dimensional Nizhnik-Novikov-Veselov(NNV)equation,many new periodic travelling wave solutions with different periods and velocities are obtained based on the knownperiodic *** procedure is crucially dependent on a sequence of cyclic identities involving Jacobi ellipticfunctions sn(ξ,m),cn(ξ,m),and dn(ξ,m).

关键词： linear superposition nonlinear equation travelling wave solution

A LATTICE BOLTZMANN METHOD FOR SIMULATION OF A THREE-DIMENSIONAL DROP IMPACT ON A LIQUID FILM

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Journal of Hydrodynamics 2008年第3期20卷 267-272页

作者： SHI Zi-yuan YAN Yong-hua YAN-G Fan QIAN Yue-hong HU Guo-hui shanghai institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China shanghai Key Laboratory of Mechanics in Energy and Environment Engineering Shanghai 200072 China shanghai East Pump （Group） Co. Ltd Shanghai 201907 China

A single-phase free surface tracking model based on the Lattice Boltzmann Method （LBM）, which has capability of simulating liquid-gas system with the assumption that the gas phase has only negligible influence on the liquid phase, is utilized to simulate the flow of a drop impacting on a liquid film. Three typical outcomes in the flows, i.e., deposition, crown and splash, which have been observed in the previous experiments, are obtained in the present three dimensional numerical simulations. The numerical results are consistent with the experimental and analytical results available.

关键词： Lattice Boltzmann Method (LBM) drop impact two-phase flows thin film

A CLASS OF C^1 DISCRETE INTERPOLANTS OVERTETRAHEDRA

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Journal of Computational Mathematics 1997年第2期15卷 149-158页

作者： X.C. Liu(institute of Image Processing and Pattern Recognition, shanghai Jiao Tong {2.,shanghai, china) institute of Image Processing and Pattern Recognition Shanghai Jiao Tong University Shanghai China

Smooth interpolants defined over tetrahedra are currently being developed for they have many applications in geography, solid modeling, finite element analysis, etc. In this paper, we will characterize a certain class of C-1 discrete tetrahedral interpolants with only C-1 data required. As special cases of the class characterized, we give two C-1 discrete tetrahedral interpolants which have concise expressions.

关键词： A CLASS OF C~1 DISCRETE INTERPOLANTS OVERTETRAHEDRA

THE GAUSS MAP OF TIMELIKE SURFACES IN R1^n

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Chinese Annals of Mathematics,Series B 1995年第3期16卷 361-370页

作者： HONG JIANQIAO(institute of Mathematics, Fudan university, {2. 2.0433, china.) FUDAN UNIV INST MATHSHANGHAI 200433PEOPLES R CHINA

Gauss maps of oriented timelike 2.surfaces in are characterized, and it is shown that Gallss maps can determine surfaces locally as they do in case. Moreover, some essential differences are discovered between the properties of the Gauss maps of surfaces in Rn and those of the Gauss maps of timelike surfaces in. In particular, a counterexample shows that a nonminimal timelike surface in cannot be essentially determined by its Gauss map.

关键词： Timelike surface Gauss map External surface.