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science china(Technological sciences) 2011年第S1期54卷 54-63页

作者： LI RuoNan 1,CHEN QiuWen 1,2 & Duan Chen 1,3.1 research center for Eco-environmental science,Chinese Academy of sciences,beijing 100085,china 2 china Three Gorges University,Yichang 443.02,china 3.Hydraulics department,Changjiang River Scientific research Institute,Wuhan 43.010,china 1. research center for Eco-environmental science Chinese Academy of Sciences Beijing 100085 China 2. china Three Gorges University Yichang 443002 China 3. Hydraulics department Changjiang River Scientific Research Institute Wuhan 430010 China

Hydropower development changes the river hydrological regime,thereby altering river ecosystem *** important measure for reducing degradation of ecosystem is to determine ecological flow and implement it by reservoir *** paper described a method to calculate river ecological flow based on fish habitat conservation and applied it to Jinping River Bend of Yalong *** chongi was selected as target species,and the fish habitat model coupling with water environmental model was developed according to the relationship between fish and water environment ***,improved hydraulic habitat suitability index(IHHS) and habitat fragment index(HFI) varying with discharge were discussed in this *** area representing average annual flow was taken as a reference,and then ecological hydrographs under different habitat conservation levels were calculated considering season variation and life stages of *** to the natural condition,the model results indicated that the reservoir operation clearly influenced the habitat of the target *** was proposed to ensure flow releases to maintain 70%-90% habitat in section after joint while about 60% before joint.

关键词： river habitat habitat assessment ecological flow ecological hydrograph

The Process of TiB_2-Cu Composite Phase and Structure Formation during Combustion Synthesis

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Journal of Wuhan University of technology(Materials science) 2006年第4期21卷 113-116页

作者：徐强 School of Materials science and Engineering Beijing Insitute of TechnologyBeijing 100081China

The reaction process of combustion synthesis for TiB2 -Cu was investigated in detail using combustion-wave arresting experiment, X-ray diffraction （ XRD ） analysis, SEM analysis and differential thermal analysis （ DTA ）. The XRD analysis results for the different parts of the quenched specimen show that TiCux intermetallic phase firstly forms with the propagation of combustion wave, and then Ti1.87 B50 and Ti3.4 metastable phases come forth due to the diffusion of B atoms and finally the stable TiB2 phase forms because of the continuous diffusion of B atoms. The formation of TiB2 phase is uot completed by one step, but undergoes several transient processes. The process of reaction synthesis for Ti-B-Cu ternary system can be divided into three main stages： melting of Cu and Ti , and the formation of Cu- Ti melt and few TiCux , TiBx intermetallic phases ; large numbers of TiCux intermetallic phases formation and some fine TiB2 particles precipitation ; and the TiB2 particles coarsening and the stable TiB2 and Cu two phases formation in the final product.

关键词： combustion synthesis reaction process TiB2 phase combustion-wave arresting experiment

广东深圳长圳公共租赁住房新型建造技术集成项目

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建筑实践 2024年第3期 104-111页

作者： china Construction science technology Group Co., Ltd. Shenzhen General Institute of Architectural Design and {3. Co., Ltd. 中建科技集团有限公司深圳市建筑设计研究总院有限公司

长圳公共住房及其附属工程项目（以下简称长圳项目）位于深圳市光明区,是深圳市规模最大的装配式公共住房项目和深圳市建设管理模式改革创新的试点项目。项目总投资58亿元,地上建筑24栋,总建筑面积约115万m2,其中:住宅建筑面积81万m2,...

长圳公共住房及其附属工程项目（以下简称长圳项目）位于深圳市光明区,是深圳市规模最大的装配式公共住房项目和深圳市建设管理模式改革创新的试点项目。项目总投资58亿元,地上建筑24栋,总建筑面积约115万m2,其中:住宅建筑面积81万m2,商业建筑6.5万m2,公共配套设施3.2万m2,多层建筑高度10—24m,高层建筑高度100—150m,提供近万套人才安居住房。

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Parameter identification theory of a complex model based on global optimization method

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science china(Physics,Mechanics & Astronomy) 2008年第11期51卷 1722-1732页

作者： QU Jie1, JIN QuanLin2 & XU BingYe3.1 College of Automotive Engineering, South china University of technology, Guangzhou 510640, china 2 {3. research Institute of Mechanical and Electrical technology, {3. 100083. china 3.department of Engineering Mechanics, Tsinghua University, {3. 100084, china 1. College of Automotive Engineering South China University of Technology Guangzhou 510640 China 2. beijing research Institute of Mechanical and Electrical technology Beijing 100083 China 3. department of Engineering Mechanics Tsinghua University Beijing 100084 China

With the development of computer technology and numerical simulation technology, computer aided engineering (CAE) technology has been widely applied to many fields. One of the main obstacles, which hinder the further application of CAE technology, is how to successfully identify the parameters of the selected model. An elementary framework for parameter identification of a complex model is provided in this paper. The framework includes the construction of objective function, the design of the optimization method and the evaluation of the identified results, etc. The parameter identification process is described in this framework, taking the parameter identification of the superplastic constitutive model considering grain growth for Ti-6Al-4V at 927°C as an example. The objective function is the weighted quadratic sums of the difference between the experimental and computational data for the stress-strain relationship and the grain growth relationship; the designed optimization method is a hybrid global optimization method, which is based on the feature of the objective function and incorporates the strengths of genetic algorithm (GA), the Levenberg-Marquardt algorithm and the augmented Gauss-Newton algorithm. The reliability evaluation of parameter identification result is made through the comparison between the calculated and experimental results and between the theoretical values of the parameters and the identified ones.

关键词： constitutive model parameter identification theory inverse analysis global optimization

Fuzzy tolerance quotient spaces and fuzzy subsets

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science china(Information sciences) 2010年第4期53卷 704-714页

作者： ZHANG Ling1 & ZHANG Bo2,3.4* 1Computer science & technology College, Anhui University, Anhui 23.03., china 2State Key Laboratory of Intelligent technology and Systems, beijing 100084, china 3.singhua National Laboratory of Information science & technology, beijing 100084, china 4Information science & technology College, Computer science & technology department, Tsinghua University, beijing 100084, china 1. Computer science & technology College Anhui University Anhui 230039 China2. State Key Laboratory of Intelligent Technology and Systems Beijing 100084 China3. Tsinghua National Laboratory of Information Science & Technology Beijing 100084 China4. Information Science & Technology College Computer Science & Technology Department Tsinghua University Beijing 100084 China

The structure and characteristic of fuzzy subsets are discussed by using the concepts of granulation and hierarchy in quotient space theory. First, the equivalence relation based quotient space theory is extended to the fuzzy tolerance relation. Second, the isomorphism and its discriminant of fuzzy tolerance relations are discussed. Finally, by using the fuzzy tolerance relation to define the fuzzy subset, its properties are addressed. The main results are given below: (1) several equivalent statements of fuzzy tolerance relations; (2) the definition of isomorphism of fuzzy tolerance relations; (3. the isomorphic discriminant of fuzzy tolerance relations; (4) the definition and properties of fuzzy subsets based on the fuzzy tolerance relations; and (5) the necessary and sufficient condition of the isomorphism of fuzzy subsets. These results will help us further comprehend the concepts of fuzzy tolerance relations and fuzzy subsets.

关键词： Fuzzy tolerance relation quotient space isomorphism fuzzy subset

A Method for Generating Super Large Fractal Images Useful for Decoration Art

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Communications in Nonlinear science and Numerical Simulation 1996年第3期1卷 24-27页

作者： Huajie LIU Jun LUO(research center for science & Society Peking University, P.R.{3.)(department of Computer science & technology, Peking University, P.R.{3.) [b] research center for science & Society Peking University P.R. china [a] department of Computer science & {3. Peking University P.R. china

Many authors have reported the techniques to iterate nonlinear equations oncomplex plane, but generally, the sise of image calculated by usual VGA style (640×480) istoo small to fit the needs for high quality publications or decorative patterus. We describea universal method for generating and storing (in *.GIF format) fractal forge large enoughas you need, such as an wie 5000×5000 256-color(25,000, 74 bytes 23.8MB), whichcan thoroughly display the intricate beauty of fractals.

关键词： super large fractal images iteration decoration art

Pre-LOI trajectory maneuvers of the CHANG'E-2 libration point mission

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science china(Information sciences) 2012年第6期55卷 1249-1258页

作者： WU WeiRen 1,LIU Yong 2,3.LIU Lei 2,3.ZHOU JianLiang 3.TANG GeShi 2,3.& CHEN YongZhi 3.1 Chinese Lunar Exploration and Space Project center,beijing 10003.,china 2 {3. and technology on Aerospace Flight Dynamics Laboratory,beijing 100094,china 3.beijing Aerospace Control center,beijing 100094,china 1. Chinese Lunar Exploration and Space Project center Beijing 100037 China2. Science and Technology on Aerospace Flight Dynamics Laboratory Beijing 100094 China3. Beijing Aerospace Control Center Beijing 100094 China

This paper addresses pre-LOI (before Lissajous orbit insertion) trajectory maneuvers for the libration point mission of CHANG'E-2,which is the first Chinese satellite to fly to the Sun-Earth L2 libration point and the first satellite ever to fly to the L2 point from lunar ***,a transfer trajectory for the mission is designed based on InterPlanetary Superhighway theory under the constraint of the remaining propellant,TT&C (telemetry,track and command) and sunlight *** effects of trajectory maneuver errors on the mission are also ***,based on the analysis results,the article investigates the trajectory maneuver schemes for the lunar escape and transfer trajectory maneuvers employing mathematical models and operational *** mission status based on our maneuver schemes is then presented,and the results of control operation and corresponding analysis are provided in ***,the future trajectory maneuver in the Lissajous orbit is *** to the analysis of the CHANG'E-2 TT&C data,the trajectory maneuver schemes proposed in the article work properly and efficiently.

关键词： CHANG’E-2 libration point trajectory maneuver escape trajectory transfer trajectory

Exotic structure of the third excited state in^(21)Na

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Chinese science Bulletin 2005年第23期50卷 2677-2680页

作者： LI Xihan1,2,3. LIANG Yujie1,2,3. DENG Fuguo1,2,3. LIU Zuhua1,4 & ZHOU Hongyu1,2,3.1. Key Laboratory of Beam technology and Material Modification of Minister of Education, beijing Normal University, beijing 100875,{3. 2. Institute of Low Energy Nuclear Physics, and department of Material science and Engineering, beijing Normal University, beijing 100875,{3. 3. beijing Radiation center, beijing 100875,{3. 4.{3. Institute of Atomic Energy, beijing 102413.{3. Key Laboratory of Beam technology and Material Modification of Minister of Education Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear Physics and Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation center Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The probability of the last proton being out of the binding potential, P and the root-mean-square (rms) ra- dius (1/2= of the third excited state in 21Na are calcu- lated by means of asymptotic normalization coefficient (ANC) method with the experimental date existing. The results are P=54.73. and 1/2=5.28 fm respectively. The P value and the contribution of the asymptotic part to the 1/2 are compared with those of several other low energy states in 21Na. It is found that the valence particle in the third excited state has an obvious larger P than those of other states. The density distribution of the valence proton in this state is also compared with the nucleons in the nuclear core 20Ne, and a far extended tail can be seen clearly. These results show that the third ex- cited state in 21Na is a proton halo state.

关键词：钠第三激发态外部结构有效半径密度分布渐近标准化系数

Estimating surface evapotranspiration using combined MODIS and CBERS-02 data

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science china(Technological sciences) 2005年第S2期48卷 145-160页

作者： XIN Xiaozhou1,2, LIU Qinhuo1, TANG Yong1,3. TIAN Guoliang1, GU Xingfa1, LI Xiaowen1,2, ZHENG Hongsheng4 & CHEN Jiayi4 1. State Key Laboratory of Remote Sensing science, Institute of Remote Sensing Applications, Chinese Academy of sciences, beijing 100101,{3. 2. research center for Remote Sensing and GIS, department of Geography, beijing Normal University, beijing 100875,{3. 3. Graduate University of Chinese Academy of sciences, beijing 10003.,{3. 4. department of Atmospheric Physics, Peking University, beijing 100871,{3. 1. State Key Laboratory of Remote Sensing science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China2. Research Center for Remote Sensing and GIS Department of Geography Beijing Normal University 100875 Beijing China3. Graduate University of Chinese Academy of Sciences 100039 Beijing China4. Department of Atmospheric Physics Peking University 100871 Beijing China

Spatial scale error is one of the most serious problems in the estimates of land surface heat fluxes of sensible and latent from satellite-borne data such as MODIS 1km resolution reflectance and emissive data. One of the feasible and economic ways to decrease the spatial scale error is to use high resolution land use class data together with the MODIS data. CBERS-02 data were used to produce land use class of Baiyangdian area, Hebei Province, china in the autumn of 2004. The area ratio of each class in MODIS pixel was calculated, and used to derive the heat fluxes of the mixed pixel. The results showed that the estimated heat fluxes of soil, sensible and latent have been changed remarkably after using the high resolution land class data. It could be concluded from the comparison between simulated and ground-measured fluxes as well as the theoretical analysis that high resolution land class data are useful to diminishing the scale error of heat fluxes estimated from low resolution satellite data.

关键词： surface evapotranspiration spatial scale error MODIS CBERS land class.

Preparation of semi-solid AlSi7Mg alloy slurry with big capability

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Rare Metals 2010年第6期29卷 642-645页

作者： LI Sha and MAO Weimin School of Materials science and Engineering,University of science and technology {3.,{3. 100083.china School of Materials science and Engineering University of Science and Technology Beijing Beijing China

Semi-solid AlSi7Mg alloy slurry was prepared by low superheat pouring and weak traveling-wave electromagnetic *** effects of pouring temperature and stirring power on the microstructure of AlSi7Mg alloy slurry were *** results show that the semi-solid AlSi7Mg alloy slurry of 5 kg can be *** new technology can save energy and make the pouring process *** the pouring temperature is decreased at a stirring power of 0.41 kW,the shape of primary α-Al grains gradually changes from dendritic-like to *** the alloy melt is poured at the temperature（63.°C） with a certain superheat,the pouring process becomes easier,and the spherical microstructure of AlSi7Mg alloy slurry can be prepared by the weak traveling-wave electromagnetic *** the pouring temperature is 63.°C,increasing the stirring power appropriately can result in better spherical primary α-Al grains,but if the stirring power is increased to a certain value（1.72 kW）,the shape of primary α-Al grains does not obviously improve when the stirring power is continually increased.

关键词： aluminum alloys metal forming semisolid slurry electromagnetic stirring microstructure