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Advances in estimation methods of vegetation water content based on optical remote sensing techniques

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Science china(Technological sciences) 2010年第5期53卷 1159-1167页

作者： ZHANG JiaHua1,XU Yun1,YAO FengMei2.WANG PeiJuan1,GUO WenJuan1,LI Li1 & YANG LiMin3.1 Chinese Academy of Meteorological sciences,{2. 100081,china 2.{3. university of Chinese Academy of sciences,{2. 100049,china 3.USGS/EROS Data Center,South Dakota 57198,USA Chinese Academy of Meteorological sciences Beijing China graduated university of Chinese Academy of {2. Beijing China USGS/EROS Data Center South Dakota USA

Quantitative estimation of vegetation water content(VWC) using optical remote sensing techniques is helpful in forest fire as-sessment,agricultural drought monitoring and crop yield *** paper reviews the research advances of VWC retrieval using spectral reflectance,spectral water index and radiative transfer model(RTM) *** also evaluates the reli-ability of VWC estimation using spectral water index from the observation data and the *** on two main definitions of VWC-the fuel moisture content(FMC) and the equivalent water thickness(EWT),the retrieval accuracies of FMC and EWT using vegetation water indices are ***,the measured information and the dataset are used to estimate VWC,the results show there are significant correlations among three kinds of vegetation water indices(i.e.,WSI,NDⅡ,NDWI1640,WI/NDVI) and canopy FMC of winter wheat(n=45).Finally,the future development directions of VWC detection based on optical remote sensing techniques are also summarized.

关键词： optical remote sensing vegetation water content estimation method water index FMC EWT radiative transfer model

Assessing the Carrying Capacity of Tourist Resorts: An Application of Tourists’ Spatial Behavior Simulator Based on GIS and Multi-Agent System

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Wuhan university Journal of Natural sciences 2005年第4期10卷 779-784页

作者： ZHANG Ren-jun 1,2.1. Institute of Mountain Hazards and Environment, Chinese Academy of sciences, Chengdu 610041, Sichuan, china 2. {2. School of the Chinese Academy of sciences, beijing 10003., china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China graduated School of the Chinese Academy of sciences Beijing China

Based on the study of visitors' individual spatial behaviors, a tourists'spatial behavior simulator (TSBS) to assess the carrying capacity of tourist resorts was developed,TSBS employs GIS (Geographic Information System) to manage the spatial data,and Multi-Agent systemto simulate the actions of individual visitors. By utilizing TSBS, visitors' travel patterns such aslocation, cost, and state can be analyzed and predicted. Based on this analysis and prediction, themodel of assessing the carrying capacity of resorts is built. Our results show that TSBS will be aneffective tool to accurately assess the carrying capacity of tourist resorts.

关键词： tourist resort carrying capacity TSBS GIS Multi-Agent simulator

A new seismic isolation system and its feasibility study

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Earthquake Engineering and Engineering Vibration 2010年第1期9卷 75-82页

作者： Jia Gaofeng~+ and Shi Zhifei~(++) School of Civil Engineering,beijing Jiaotong university,beijing 100044,{3. graduated Student ++ Professor School of Civil Engineering Beijing Jiaotong University Beijing China

This paper introduces a new seismic isolation system called a periodic foundation （PF）, where inclusions are periodically arranged. The PF is different from traditional base isolation in that it causes a fundamental frequency shift in the structure, thus reducing its response and generating a frequency gap. If the frequency contents of a seismic wave fall into the gap, it can not propagate in the foundation. Thus, it will exert no influence on the structure above. A systematic study of the band of frequency gap for a 2. PF is conducted. The influence of physical and geometrical parameters such as density and elastic modulus as well as filling fraction of the PF and its materials on the band of frequency gap are investigated, and a design with a frequency gap as low as 2.49-3.72.Hz is achieved. This band of frequency gap corresponds well to the design spectra in earthquake engineering. Numerical simulations of a six-story frame structure with different foundations demonstrate that a proposed PF can greatly reduce the seismic response of an isolated structure. This investigation shows that PFs have great potential in future applications of seismic isolation technology.

关键词： seismic isolation periodic foundation band of frequency gap

Neutron-induced apoptosis of HR83.8 cells in vitro

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World Journal of Gastroenterology 2001年第3期7卷 435-439页

作者： Li Ping Wang~1 Ke Liang~2.Yu Shen~2.Wei Bo Yin~2.G.Hans~3.Yan Jun Zeng~1 ~1Biomechanics & Medical Information Institute,beijing Polytechnic {2.,Beijng 10002.,china ~2.epartment of Gastrointestinal Surgery,Aalborg {2.,Denmark ~3.ancer Institute (Hospital),Chinese Academy of Medical sciences,Peking Union Medical College,beijing 10002.,chinaLi Ping Wang graduated from beijing Polytechnic {2. in 2.00,major in tumor radiotherapy,having 3.papers published. Biomechanics & Medical Information Institute Beijing Polytechnic University No.100 Ping Le Yuan Chao Yang District Beijing 100022 China.

INTRODUCTIONTo date ,the major therapy for rectal carcinoma is extensive abdomino-perineal resection[1]. Unfortunately ,after resection of rectal carcinoma ,many patients still die of blood-borne metastases ,usually in the liver or lungs ,or local prlvic recurrence[2.3.,which is the major cause of morbidity and mortality in patients with rectal carcinoma .Pre-or postoperative radiotherapy can reduce the incidence of local rdcurrence[4-7].

关键词： Adenocarcinoma Fast Neutrons Rectal Neoplasms Apoptosis Dose-Response Relationship, Radiation Humans Immunohistochemistry In Vitro Proto-Oncogene Proteins c-bcl-2 Research Support, Non-U.S. Gov't Tumor Cells, Cultured Tumor Suppressor Protein p53

Spatial and environmental effects on plant communities in the Yellow River Delta,Eastern china

维普期刊数据库评论

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维普期刊数据库

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Journal of Forestry Research 2009年第2期20卷 117-122页

作者： SONG Chuang-ye1, 2. LIU Gao-huan1, LIU Qing-sheng1 1 Institute of Geographic sciences and Nature Resources Research, Chinese Academy of sciences, {2. 100101,{3. 2.graduated School of Chinese Academy of sciences, beijing 10003.,{3. Institute of Geographic sciences and Nature Resources Research Chinese Academy of Sciences Beijing China graduated School of Chinese Academy of sciences Beijing China

Types and structure of plant communities in the Yellow River Delta were investigated by using detrended canonical correspon-dence analyses(DCCAs) and a two-way indicator species analysis(TWINSPAN).The distribution pattern and influential factors of the plant communities were also analyzed by testing elevation, slope, soil characteristics, longitude and latitude of 13. vegetation samples collected by representative plot sampling *** showed that all the 13. vegetation samples could be divided into seven vegetation groups, separately dominated by Robinia pseucdoacacia, Imperata cylindrical, Miscanthus saccharifleus, Suaeda salsa, Aeluropus sinensis, Phragmites australis and Tamarix *** vegetation distribution pattern was mainly related to elevation, ground water depth and soil characteristics such as salinity and soluble *** the factors affecting distribution pattern of the plant communities, the species matrix explained by non-spatial environmental variation accounts for 45.2. of total *** variation and spatial-structured environmental variation explain 11.8%, and 2.2., *** 40.8% of undetermined variation is attributed to biological and stochastic factors.

关键词： detrended canonical correspondence analyses environmental factors plant communities spatial factors Yellow River Delta two-way indicator species analysis

兔植入前移核胚中发育相关基因的差异表达分析

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生物化学与生物物理进展 2003年第5期30卷 813-818页

作者：李文雍齐冰王玉阁郁卫东杜淼陈清轩中国科学院遗传与发育生物学研究所

与早期胚胎发育相关的一些重要基因异常表达致使克隆胚细胞核的再程序化过程受阻,是导致动物克隆失败的重要原因.为了分离鉴定再程序化相关基因,我们改进了mRNA差异显示技术,成功地建立了单胚差示技术体系.以不同发育时期的兔克隆胚(M... 详细信息

与早期胚胎发育相关的一些重要基因异常表达致使克隆胚细胞核的再程序化过程受阻,是导致动物克隆失败的重要原因.为了分离鉴定再程序化相关基因,我们改进了mRNA差异显示技术,成功地建立了单胚差示技术体系.以不同发育时期的兔克隆胚(MⅡ卵、2.胞、4细胞、8～ 16细胞克隆胚胎)为材料进行单胚差示,分离了 80个差异片段.经反向RNA印迹验证、亚克隆、序列分析及NCBIGenBank数据库检索,结果表明:A0 2.8片段与CstF3.因有 93.的同源性,在早期胚胎发育过程中的表达有阶段特异性,该基因在兔克隆胚的早期发育过程中起重要作用.RNA印迹显示:该基因在所检测的组织中,只在卵巢中有表达.

关键词：差异表达分析发育相关基因兔克隆胚胎再程序化单胚差异显示技术

CORRECTION OF WALL SLIP EFFECTS AND RHEOLOGICAL MEASUREMENT OF HIGH CONCENTRATED COAL WATER SLURRY

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中国有色金属学会会刊：英文版 1993年第3期3卷 7-11页

作者： Yang, Xiaosheng Zhang, Rongzeng Chen, Jin Central-South university of Technology, Changsha 410083.{2. Mineral Engineering Department, The graduated School,{2. university of Mining and Technology, beijing 100083.{2.

Coal-water slurry, a ncw liquid fuel, began to appcar during the world-wide petroleum crisis in the seventies of this century. Its applications to substitute petroleum drew great attention on the investigations of its preparation, combustion and transportation, etc. The rheological behavior is an important quality index for the fuel. However, the conventional viscosimeters designed for true fluids are not suited to the high concentrated slurry due to the complicated rheological bchavior. A special viscosimeter of tube type was rcpresented, which was designed and set up by the authors for the measurement of the theology of high concentrated coal-water slurry and experiments were conducted with two kinds of slurries from P. R. china. In consideration of the wall sliD effects the correction of the experimental data were made.

关键词： coal-water slurry diameter effects plastic viscosity

New Quaternary Mammalian Faunas and Cave Deposits in the Zhoukoudian Area,beijing

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Acta Geologica Sinica(English Edition) 1997年第3期71卷 231-243页

作者： Cheng Jie Tian Mingzhong Cao Boxun and Zhao Zhizhong china university Of Geo{2., {3. china university of Geo{2.,Wuhan, Hubei Institute of Geomechanics, Chinese Academy of Geological {2., {3. Fei Zhenbi china university of Geo{2. Beijing china university of Geo{2. Wuhan Hubei Institute of Geomechanics Chinese Academy of Geological Sciences Beijing [?]Cheng Jie Born in July 1963 graduated from the Specialty of Exploration East China College of Geology in 1984 received a master degree at china university of Geo{2. in 1987. He is now associate professor of china university of Geoscience (beijing) and engages in the teaching and study of vertebrate palaeontology and Quaternary Geology.

From 1985 to 1987, four new localities with abundant fossil mammals were dis-covered by Cao, Tian and others in the Zhoukoudian (Choukoutien) area, beijing. They are theEast, West, Shangdian and Donglingzi caves. The East Cave fauna consists of 2. speices ofmammals and its age is middle Early Pleistocene. The East Cave assemblage shows that a tem-perature-falling event took place at around 1.2. Ma B.P. at Zhoukoudian. Sixteen species ofmammals were collected from the West Cave, which are mainly forms of late Early Pleistoceneage. The West Cave fauna represents a transitional fauna from the East Cave fauna (dry-cold)to the fauna (warm) at locality 9. The Shangdian Cave fauna is composed of four forms, beingMiddle Pleistocene in age. The Donglingzi Cave fauna contains 2. Late Pleistocene forms. Inthe cave two fossil horizons may be distinguished. The age of the lower horizon is early LatePleistocene, which is equivalent to that of the New Cave fauna; while the fauna of the upper ho-rizon may be correlated with the Upper Cave fauna.

关键词： Zhoukoudian Quaternary mammalian fauna biostratigraphy

MICROSTRUCTURE STUDY OF CONSTITUENT PHASES IN 2.2. SERIES Al ALLOYS

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Acta Metallurgica Sinica(English Letters) 1990年第2期3卷 104-109页

作者： WANG Shuncai LI Chunzhi YAN Minggao Institute of Aeronautical Materials,beijing,china BIAN Weimin Northeast Institute of Technology,Shenyang,china WANG Shuncai {3. Student,Institute of Aeronautical Materials,beijing 100095,china

X-ray microanalysis,convergent beam electron diffraction(CBD)and selected area electron diffraction(SAD)studies on the structures and compositions of the constituent phases in 2.2. series Al alloys have been *** substitution of alloying elements is found to occur in all the constituent phases,which cause small deviations from the stoichiometric com- positions reported in these ternary *** dominant phase is α-Al_(12.(FeMn)_3.i which has a body center cubic crystal structure with the Im■ space group and a=1.2. *** next dominant phase is Cu_2.eAl_7 which has a primitive tetragonal crystal structure with the P4/mnc space group and a=0.63.6 nm,c=1.487 *** minor phase is α'-Al_(12.Fe_3.i hav- ing α primitive cubic crystal structure with the Pm■ space group and α=1.2. nm.

关键词： Al alloy constituent phases microstructure