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Developing land use scenario dynamics model by the integration of system dynamics model and cellular automata model

science china Earth sciences 2005年第11期48卷 1979-1989页

作者： HE Chunyang, SHI Peijun, CHEN Jin, Li Xiaobing, PAN Yaozhong, LI Jing, LI Yuechen & LI Jinggang Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of china, Beijing normal {2. {3. of resources science & technology, Beijing normal {2., Beijing 100875, china Key Laboratory of Environmental Change and Natural Disaster Ministry of Education of China Beijing Normal University China college of resources {2. & {3. Beijing Normal University Beijing China

Modeling land use scenario changes and its potential impacts on the structure and function of the ecosystem in the typical regions are helpful to understanding the interactive mechanism between land use system and ecological system. A Land Use Scenario Dynamics (LUSD) model by the integration of System Dynamics (SD) model and Cellular Automata (CA) model is developed with land use scenario changes in northern china in the next 2. years simulated in this paper. The basic idea of LUSD model is to simulate the land use scenario de-mands by using SD model at first, then allocate the land use scenario patterns at the local scale with the considerations of land use suitability, inheritance ability and neighborhood effect by using CA model to satisfy the balance between land use scenario demands and supply. The application of LUSD model in northern china suggests that the model has the ability to reflect the complex behavior of land use system at different scales to some extent and is a useful tool for assessing the potential impacts of land use system on ecological system. In addition, the simulated results also indicate that obvious land use changes will take place in the farming-pastoral zone of northern china in the next 2. years with cultivated land and urban land being the most active land use types.

关键词： system dynamics, cellular automata, scenario, land use, model

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Weighted composition operators between μ-Bloch spaces on the unit ball

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science china Mathematics 2005年第10期48卷 1349-1368页

作者： ZHANG Xuejun~1 & XIAO Jianbin~2.1. college of Mathematics and Computer science,Hunan {2. {3.,Changsha 410006,china(email:xuejunttt@2.3. net) 2. The School of science,Hangzhou Dianzi {3.,Hangzhou 3.003.,china college of Mathematics and Computer science Hunan Normal University Changsha China The School of science Hangzhou Dianzi University Hangzhou China

In this paper,necessary and sufficient conditions are given for the weighted composition operator T_(ψ,ψ) to be bounded or compact from the space β_μ to β_ν (or β_(μ,0) to β_(ν,0) ) on the unit ball of C^***... 详细信息

关键词： μ-Bloch space, weighted composition operator, boundedness, compactness.

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Bionic Design and Finite Element Analysis of Elbow in Ice Transportation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2., Xiuhua Sui~3. Linjing Xiao~3.1. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education,{2.), Shandong university of science and {3., Qingdao 2.6510, P. R.{2. 2. School of Architecture, Tsinghua university, Beijing 100084, P. R.{2. 3. college of Mechanical and Electronic Engineering, Shandong university of science and {3., Qingdao 2.6510, P. R.{2. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education China) Shandong University of Science and Technology Qingdao P. R. China School of Architecture Tsinghua University Beijing P. R. China college of Mechanical and Electronic Engineering Shandong University of Science and Technology Qingdao P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice transportation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice transportation flow resistance reduction pressure loss

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A new DNA algorithm to solve graph coloring problem

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Progress in Natural science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2. Meng Ya3.and Meng Dazhi2.1. National Laboratory of Pattern Recognition,Institute of Automation, Chinese Academy of sciences, Beijing 100080,{2. 2. college of Applied sciences, Beijing university of technology, Beijing 10002.,{2. 3. School of science, Beijing Institute of technology, Beijing 100081,{2.) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China National High Magnetic Field Laboratory Florida State University 1800 East Paul Dirac Drive Tallahassee Florida 32306 USA

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

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Research on Methods of Ecological Security Assessment of the Middle and Lower Reaches of Liaohe River Based on GIS

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Chinese Journal of Population,resources and Environment 2005年第4期3卷 20-25页

作者： Wang Geng 1,2., Nie Baochi 3. Wang Lin 1 & Wu Wei 1 1. School of Environmental and Biological science and {2., Dalian university of {2., Dalian 11602., china 2. Urban and Environmental School, Liaoning normal university, Dalian 11602., china 3. Shenyang Buraue of Water resources, Shenyang 110013. china. School of Environmental and Biological science and technology Oalian University of Technology Oalian 116024 China Urban and Environmental School Uaoning Nonnal University Oalian 116029 China Shenyang Buraue of Water resources Shenyang 110013 China

Ecological security assessment and early warning research possess the attributes of spatiality, non-linearity and randomicity, so we must process much spatial information. Spatial analysis and data management are the advantages of GIS, which can define distribution trend and spatial relations of environmental factors, and show ecological security pattern graphically. Spatial differences of ecological security assessment based on GIS are discussed in this paper, of which the middle and lower reaches of the Liaohe River is taken as a study case. First, to work out pressure-state-response (P-S-R) assessment indicators system, and investigate in person and gather information; second, to digitize the watershed; third, to quantize and calculate by the fuzzy method; last, to construct GIS grid database, and expound spatial differences of ecological security by GIS interpolation and assembly analysis.

关键词： the middle and lower reaches of the Liaohe River ecological security assessment indicators system GIS spatial differences

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Superconductivity of small metal grains

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science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2.& ZHU Shunquan1,3.1. Department of Physics, Shanghai normal {2., Shanghai 2.02.0}, china 2. Department of Physics, Southwest normal {2., Chongqing 400715, china 3. Department of Computer and Electric technology, Shanghai Business School, Shanghai 2.1400, china Department of Physics Shanghai Normal University Shanghai China Department of Physics Southwest Normal University Chongqing China Department of Computer and Electric technology Shanghai Business School Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

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Spatio-temporal pattern analysis of single-trial EEG signals recorded during visual object recognition

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science china(Information sciences) 2011年第12期54卷 2519-2527页

作者： WANG ChangMing 1 , HU XiaoPing 3., YAO Li 1,2., XIONG Shi 2.& ZHANG JiaCai 2.1 National Key Laboratory of Cognitive Neuroscience and Learning, Beijing {2. university, Beijing {3., china 2.college of Information science and technology, Beijing {2. university, Beijing {3., china 3.Biomedical Imaging technology Center, Emory university/Georgia Institute of technology, Atlanta 3.3.2. USA National Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University college of Information science and {2. Beijing Normal University

Object discrimination is a fundamental cognitive function for human brains. In this study, we utilized an analysis approach for single-trial electroencephalography (EEG) to analyze the spatio-temporal activation patterns of visual objects processing in human brains, and attempted to apply it to discriminate different visual objects. The spatial patterns were respectively extracted from scalp EEG and the reconstructed cortical sources, while the experiment participants were perceiving 4 different categories of visual objects (faces, buildings, cats and cars). By classifying the patterns extracted from single-trial EEG, the presented visual objects could be discriminated by a computer, and the classification accuracies may provide a quantitative index to evaluate the spatial differences of the brain activations related to different visual objects. Our results demonstrated that the spatial patterns on both the scalp and the sources levels resulted in higher classification accuracies than chance rate. We also examined the classification results using temporally non-overlapping time intervals of different event-related potential (ERP) components. The temporal changes of classification accuracies may reflect the temporal distribution of the discriminative information in the EEG responses. The present pattern extraction and classification methods may compose a computational model for single-trial EEG data analysis in investigations of the spatio-temporal activation patterns for object recognition. These spatio-temporal patterns in EEG may be useful to identifying the discriminative spatial areas and time stages to improve the accuracies and efficiencies of object discrimination. In addition, investigating and utilizing humans'cognitive mechanisms of object recognition may improve computers' processing efficiency of visual information.

关键词： EEG spatio-temporal pattern object recognition single-trial analysis visual information processing

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Influence of valence electron structures of phase and biphase interfaces of sulfides on hot brittleness in steel

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science china(Technological sciences) 2004年第4期47卷 488-504页

作者： LIU Yan1,3. LIU Zhilin1, ZHANG Chengwei1,2.& ZHOU Yingchun1 1. Liaoning Institute of technology, Jinzhou 12.001,{2. 2.{2. National Oil and Gas Exploration and Development Corporation, Beijing 100011,{2. 3. college of science, Northeastern university, Shengyang 110006,{2. Liaoning Institute of technology china National Oil and Gas Exploration and Development Corporation

This paper calculates the electron structures of phase of FeS, MnS and their biphase interface electron structures with austenite in steel. The precipitation and the transformation of FeS and MnS are investigated through studying the valence electron pair numbers on the strongest bond n A with the structure formation factor S. The continuity of electron density and its relation with stress are explored in the biphase interfaces with the electron density difference απ Using n A, S, απ we explain the reason why FeS can bring about hot brittleness in steel and the physical mechanism why MnS may eliminate or inhibit hot brittleness, based on which satisfying results are obtained by calculating several rare-earth sulfides.

关键词： valence electron structure, sulfide, hot brittleness, and rare earth.

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Approach to synthesis of novel chiral 3.chloro-2.5H)- furanone and its application in asymmetric reactions

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Chinese science Bulletin 2000年第8期45卷 711-716页

作者： HUANG Hui & CHEN Qinghua1. Department of Chemistry, Tonghua Teacher’s college, Tonghua 13.002.{2. 2. Department of Chemistry, Beijing normal {3., Beijing 100875,{2. Department of Chemistry Tonghua Teacher’s College Tonghua China Department of Chemistry Beijing Normal University Beijing China

The synthetic method of the novel chiral synthon, 5-/-menthyloxy-3.chloro-2.(5H)-furanone 5a and its application in asymmetric reactions were investigated. 5a is easily obtained in highly optical purity, and acts as a stable acceptor of Michael addition with oxygen nucleophiles in tandem double Michael addition / internal nucieophilic substitution to offer the spiro-cyclopropane derivative containing four stereogenic centers 8, which it is difficult to obtain by routine methods. The synthetic methods for 5a and 8 are reported in detail and the new compounds are identified on the basis of their analytical data and spectroscopic data, such as UV, IR, H NMR,13.C NMR, MS and elementary analysis. The absolute configuration of the interesting spiro-cyclopropanes, spiro [1-chloro-4-(/-menthyloxy)-5-oxo-6-oxa-biscyclo[3.1.0]hexane-2.3.(4’-/-menthyloxy-5’-/-menthyloxy- butyrolactone)] 8 was established by X-ray crystallography. This result can provide important synthetic strategy in synthesis of some complex

关键词： new chiral synthon. 5-l-menthyloxy-3.chloro-2.(5H)-furanone absolute configuration spiro-cyclopropane derivative containing multiple chiral centers.

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The toxicity of Cu^(2.) to Microcystis aeruginosa using dielectric spectroscopy

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science china Chemistry 2010年第3期53卷 631-636页

作者： YU YanLi1,BAI Wei1,ZHAO KongShuang1& ZHOU YunLong2.1college of Chemistry,Beijing normal {2.,Beijing {3.,china 2.0} of Life science,Beijing normal {2.,Beijing {3.,china college of Chemistry Beijing Normal University Beijing China college of Life science Beijing Normal University Beijing China

Dielectric spectroscopy(DS) was utilized to investigate the toxicity of the Cu2. solution to Microcystis *** was found that 0.04 mM Cu2. had no effect on dielectric increment,whereas the Cu2. concentrations above 0.1 mM decreased the value of Δε/Δε *** toxic effect of Cu2. on *** cells was time-dependent and *** was a threshold concentration between 0.04 mM and 0.1 mM,which affected the cell membrane,suggesting that Cu2. at the concentrations higher than 0.1 mM caused serious plasmalemma damage to *** *** addition of 1 mM Ca2. or Mg2. did not protect *** cells from 1 mM Cu2. *** study demonstrates that DS monitors cell biomass facilitating observation of the toxic effects of metal ions.

关键词： Microcystis aeruginosa dielectric spectroscopy dielectric increment cupric ion toxicity

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