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3. building modeling,organization and application in digital city system

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中国科学：技术科学英文版 2010年第S1期53卷 134-142页

作者： YANG Xue 1,WENG JingNong 1,2.XIA YuBin 2.WU Lun 3.& SUI ZhengWei 3.1 College of Software,Beihang {2.,Beijing 100191,China 2.College of Computer,Beihang {2.,Beijing 100191,China {2.,{3.,Beijing 100871,China Beihang Univ Coll Software Beijing 100191 Peoples R China Beihang Univ Coll Comp Beijing 100191 Peoples R China peking Univ Inst Remote Sensing & GIS Beijing 100871 Peoples R China

The real world is a three-dimensional(3.)space requiring that 3. geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3. building model data are required in a wide range of areas such as urban planning,environmental protection,real estate management and emergency *** the same time,the development of Web service[LU1]technologies allows the possibility of the widely distributed 3. geospatial data on the web.3. city building model with its related information is an important part in the construction of a digital city system,and has become a staple resource on the web *** view of the hierarchical representation of a 3. building model,an abstract of a 3. building model based on structure details is studied,and a novel representation approach named 3. transparent building hierarchical model is presented in this *** approach fully uses both the existing 3. modeling technologies and CAD constructing mapping *** the spatial relationship description,structural components inside a building can be represented and integrated as hierarchical models in a unified 3. *** addition,based on the characteristics of the 3. building model data,a service-oriented architecture and Web service technologies for 3. city building models are *** aim of the approach is that 3. city building models can be used as a kind of data resource service on the web,and can also exist independently in various different web applications.

关键词： 3. modeling 3. transparent building hierarchical models China Star web services

Integrative inversion of land surface component temperature

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Science China Earth Sciences 2005年第11期48卷 2011-2019页

作者： FAN Wenjie1 & XU Xiru1,2.1. institute of remote {2. and Geographical Information System, {3., Beijing 100871, China 2. Center of remote {2. and gis of Beijing Normal university, Beijing 100875, China 1. institute of remote {2. and Geographical Information System Peking University 100871 Beijing China 2. Center of remote sensing and {2. of Beijing Normal {3. 100875 Beijing China

In this paper, the row winter wheat was selected as the example to study the com-ponent temperature inversion method of land surface target in detail. The result showed that the structural pattern of row crop can affect the inversion precision of component temperature evi-dently. Choosing appropriate structural pattern of row crop can improve the inversion precision significantly. The iterative method combining inverse matrix was a stable method that was fit for inversing component temperature of land surface target. The result of simulation and field ex-periment showed that the integrative method could remarkably improve the inversion accuracy of the lighted soil surface temperature and the top layer canopy temperature, and enhance inver-sion stability of components temperature. Just two parameters were sufficient for accurate at-mospheric correction of multi-angle and multi-spectral thermal infrared data: atmospheric trans-mittance and the atmospheric upwelling radiance. If the atmospheric parameters and component temperature can be inversed synchronously, the really and truly accurate atmospheric correction can be achieved. The validation using ATSRII data showed that the method was useful.

关键词： components temperature, inverse pattern, atmospheric correction

The correlation of multi-angle thermal infrared data and the choice of optimal view angles

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Science China Earth Sciences 2004年第6期47卷 570-576页

作者： FAN Wenjie1 & XU Xiru1,2.1.institute of remote {2. and {3. of peking university,Beijing 100871,China 2.Center of remote {2. and {3. of Beijing Normal university,Beijing 100875,China 1. institute of remote {2. and {3. of peking university 100871 Beijing China 2. Center of remote sensing and {2. of Beijing Normal {3. 100875 Beijing China

Based on the matrix formula of thermal infrared radiant system, the components temperature can be retrieved by the inversive matrix. Around the stability problem of retrieved result, the research work we did was focused on (i) the correlation of (wk,j) which is the key to affect the retrieval accuracy, (ii) a general method which can help us find the number of retrievable parameters and evaluate the retrieval error before its performance, (iii) the choice of “optimal viewing angle group” based on the formula of absolute error propagation. The row winter wheat field was chosen as an example. The results can provide a theoretical basis for multi-angle thermal infrared remote sensing and components temperature retrieval.

关键词： components temperature retrieval, correlation, number of retrievable parameters, optimal viewing angle group.

A static and dynamic factorscoupled forecasting model of regional rainfall-induced landslides:A case study of Shenzhen

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Science China(Technological Sciences) 2008年第S2期51卷 164-175页

作者： JIA GuiYun,TIAN Yuan,LIU Yu & ZHANG Yi institute of remote {2. and {3.,peking university,Beijing 100871,China institute of remote {2. and {3. Peking University Beijing 100871 China

Most rainfall-induced landslide forecasting models focus on the relation between landslides and rainfall,which is one of the dynamic factors,and seldom consider the stacitc factors,such as geological and geograpical *** susceptibility,however,is determinded by both static and dynamic *** article proposes a static and dynamic factors-coupled forecasting model(SDFCFM) of regional rainfall-induced landslides,which quantitatively considers both the static and dynamic factors that affect *** generalized additive model(GAM) is applied to coupling both factors to get the landslide *** the case study,SDFCFM is applied to forecast the landslide occurrences in Shenzhen during a rainfall process in *** with the rainfall logistic regression model,the resulting landslide susceptibility map illustrates that SDFCFM can reduce the forecast redundancy and improve the hit *** is both applicable and *** application of SDFCFM in landslide warning and prevention system will improve its efficiency and also cut down the cost of human and matreial resources.

关键词： regional rainfall-induced landslides static and dynamic factors-coupled forcasting model(SDFCFM) generalized additive model(GAM) landslide susceptibility

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 {2. Science, {2. of remote {2. Applications, Chinese Academy of Sciences, Beijing 100101, China 2. Research Center for remote {2. and gis, Department of Geography, Beijing Normal university, Beijing 100875, China 3. Graduate university of Chinese Academy of Sciences, Beijing 10003., China 4. Department of Atmospheric Physics, peking university, Beijing 100871, China 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 2.04. 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.

Automatic generalization of metro maps based on dynamic segmentation

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Science China(Technological Sciences) 2010年第S1期53卷 158-165页

作者： DONG WeiHua 1,TIAN Yuan 2.& ZHANG Yi 2.1 institute of Geography and remote {2.,Beijing Normal {3.,Beijing 100875,China 2.institute of remote {2. and Geographic Information System,peking university,Beijing 100871,China 1. institute of Geography and remote {2. Beijing Normal University Beijing 100875 China 2. institute of remote {2. and Geographic Information System Peking University Beijing 100871 China

A metro map is usually optimized for the readability of connections and transportation networks *** order to assure good readability and meet aesthetic considerations,a set of principles for good metro map layout are *** to these principles,a new methodology based on dynamic segmentation is presented to produce the metro maps ***,routes are constructed according to the line attribute similarity and geometry *** a set of cartographic generalization methods about the shape,angle,length,and topology are presented for these *** method is validated by Beijing metro plan *** the experiment results,it can be concluded that this new method is more effective than the static segmentation method to produce metro maps with better readability for route plans.

关键词： metro maps generalization dynamic segmentation visualization

Positioning localities from spatial assertions based on Voronoi neighboring

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Science China(Technological Sciences) 2010年第S1期53卷 143-149页

作者： GONG YongXi 1,2.3.LI GuiCai 1,LIU Yu 2.& YANG Jian 1 1 Shenzhen Key Lab of Recycling Economy,peking university Shenzhen Graduate School,Shenzhen 518055,China 2.2. of {2. {3. and Geographical Information Systems,peking university,Beijing 100871,China 3.ollege of Urban and Environmental Science,peking university,Beijing 100871,China peking Univ Shenzhen Grad Sch Shenzhen Key Lab Recycling Econ Shenzhen 518055 Peoples R China peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China peking Univ Coll Urban & Environm Sci Beijing 100871 Peoples R China

With the rapid development of Internet,much spatial information contained in non-structured or semi-structured documents is available on the World Wide *** such documents,localities are always textually described using spatial relationships and named places,instead of numerical ***,extracting positional information from locality descriptions is an important *** this paper,we bridge two aspects of locality descriptions,namely generating locality descriptions and positioning localities,and provide a method to compute probability density according to the selection probability of a reference object to describe the position of the target *** operation on uncertainty field is used to deal with locality description involving multiple reference *** metrics are introduced to measure the results of positioning *** choose the mixed selection probability function based on Euclidean distance and Voronoi stolen-area to compute probability density ***,we use three cases to demonstrate the proposed methods.

关键词： geographic information science positioning locality Voronoi neighboring probability density function

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 {2. & {3., peking university, Beijing 100871, China 2. institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 1. institute of remote {2. & {3. 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.

Framework and development of digital China

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Science China(Technological Sciences) 2008年第S1期51卷 1-5页

作者： WU Lun & TONG QingXi institute of remote {2. and Geographical Information Systems,{3.,Beijing 100871,China 1. institute of remote {2. and Geographical Information Systems Peking University Beijing 100871 China

Digital China (DC) has recently drawn much attention. It is a strategic project for China in response to the challenge of sustainable development of population,re-source,and environment. Intending to establish the national information infra-structure (NⅡ),the DC project forms a solid foundation for Chinese informatization. In such an NⅡ,multi-sourced spatial data are integrated. They focus on various themes and have different space and time features. Based on the NⅡ,numerous applications and services can be developed so that spatial information will benefit everyone. Since lots of organizations,such as governments,universities,and en-terprises,are involved in the implementation of DC,the DC project will significantly prompt the relevant scientific research as well as economic progress in China.

关键词： Digital Earth Digital China spatial information sciences and technology