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On 3D simulation of moving objects in a digital earth system

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Science china(Technological Sciences) 2008年第S2期51卷 123-132页

作者： WENG JingNong1,WU Lun2,HUANG Jian1,WANG Yang1,YANG Xue1 & HU Bin1 1 College of Software,Beihang university,beijing 100191,china 2 institute of geographical information system and remote sensing,peking university,beijing 100871,china College of Software Beihang University Beijing 100191 China institute of geographical information system and remote sensing Peking University Beijing 100871 China

"How do the rescue helicopters find out an optimized path to arrive at the site of a disaster as soon as possible?" or "How are the flight procedures over mountains and plateaus simulated?" and so *** this paper a script language on spatial moving objects is presented by abstracting 3D spatial moving objects' behavior when implementing moving objects simulation in 3D digital Earth scene,which is based on a platform of digital china named "chinaStar".The definition of this script language,its morphology and syntax,its compiling and mediate language generating,and the behavior and state control of spatial moving objects are discussed *** addition,the language's applications and implementation are also discussed.

关键词： Digital Earth chinaStar moving object script language

3D 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 university,beijing 100191,china 2 College of Computer,Beihang university,beijing 100191,china 3 institute of remote sensing and GIS,peking university,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(3D)space requiring that 3D geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3D 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 3D geospatial data on the web.3D 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 3D building model,an abstract of a 3D building model based on structure details is studied,and a novel representation approach named 3D transparent building hierarchical model is presented in this *** approach fully uses both the existing 3D 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 3D *** addition,based on the characteristics of the 3D building model data,a service-oriented architecture and Web service technologies for 3D city building models are *** aim of the approach is that 3D 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： 3D modeling 3D transparent building hierarchical models china Star web services

Study on fluctuations of plume front and turbidity maximum in the Hangzhou Bay by remote sensing data

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Acta Oceanologica Sinica 1993年第1期12卷 51-62页

作者： Li Yan Li Jing Su Jilan and Ren Fuhu Second institute of Oceanography, State Oceanic Administration, Hangzhou 310012. china institute of remote sensing, peking university, beijing 100871, china Second institute of Oceanography State Oceanic Administration Hangzhou 310012 China China

On the basis of the time series of AVHRR data from NOAA satellites and the geographical information system PURSIS, fluctuations of the plume front and the turbidity maximum in the Hangzhou Bay, reflected by the distributions of temperature and suspended sediment concentration respectively, are studied in view of long-term behaviors or seasonal and tidal cycles. The data suggest that the effect of front plays an important role in the development of the turbidity maximum close to the Changjiang Estuary > while the effect of tide dominates over the development of another very turbid water situated in the shoal areas in the southern Hangzhou Bay.

关键词： esturary front suspended sediment remote sensing geographical information system Hangzhou Bay

The Relation of Department Components and Activity in Spatial information Infrastructure

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Wuhan university Journal of Natural Sciences 2001年第Z1期6卷 460-466页

作者： Yi Shan zhen 1, Zhou Li zhu 1,Cheng Ji cheng 2, Li Qi 2 1.Department of Computer Science and Technology,Tsinghua university, beijing 100084, china 2.institute of remote sensing and geographical information system,peking university,beijing 1008 Department of Computer Science and Technology Tsinghua University Beijing 100084 China

Spatial information Infrastructure (SII) facilitates the sharing, interoperability and integration of geographical information among department components of a region or a country. The SII is developed and shared by different department components. The relation of department components is a fundament for collaborating tasks and information exchange in SII. There are two kinds of department components, one is the provider which produces geospatial data of SII, other is the consumer which uses geospatial data of SII. The consumer includes two kinds of user, one is the user which only uses and does not produce geospatial data in SII, other is the special user which not only uses but also produces geospatial data in SII. The provider includes different hierarchies corresponding to different kinds of geospatial data in SII. All providers in the hierarchies form provider actor set PA. All consumers also form consumer actor set CA. The sender recipient relation SR and SRI are defined on Cartesian product of PA and CA. Five tasks and information flow in SII demonstrate the geospatial data acquisition, information production, management, and application among department components. The tasks and their sub tasks are subdivided activities. Each activity corresponds to the relation SR or RSI. The activity along with the relation of provider and consumer forms a scheme of geographical information exchange between department components.

关键词： geographical information exchange relation activity information infrastructure

Features and trends of the environmental change in the arid areas in Central Asia

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Science china Earth Sciences 2007年第S1期 142-148页

作者： ZHOU KeFa1,2, ZHANG Qing3, CHEN Xi1 & SUN Li1 1 Xinjiang institute of Ecology and Geography, Chinese Academy of Sciences, ürümqi 830011, china 2 Graduate university of Chinese Academy of Sciences, beijing 100049, china 3 institute of remote sensing and geographical information system, peking university, beijing 100871, china

RS-monitoring index systems of ecological environment changes at a large scale, based on empirical data and trends in environmental change in Central Asia, are developed using NOAA and MODIS data. Moreover, with the help of mathematical statistics and GIS spatial analysis, the degrees, hazards and distribution extent of various possible ecological problems are discussed, environmental changes in Central Asia in 1990 and 2005 are separately evaluated, and dynamic changes in the environment in Central Asia over a 15-year period are analyzed. The results reveal that during the 15-year period from 1990 to 2005, areas of degenerated vegetation in Kazakhstan, Uzbekistan, Turkmenistan, Kirghizstan and Tadzhikistan were enlarged by 0.069×105 km2, 0.081×105 km2, 0.296×105 km2, 0.022×105 km2 and 0.112×105 km2, respectively. The ecological environment in Central Asia was in the state of significant degeneration and even deterioration. This study proves that NOAA and MODIS data can be used to successfully monitor the environment and provide useful results.

关键词： Central Asia ecological environment vegetation coverage GIS RS

A new method for stabilization of video images with large moving object

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A new method for stabilization of video images with large mo...

基于iPlanet技术的数字影像电子商务系统的研究

2007亚洲光电子会议电子成像与多媒体技术分会场

作者： Pengqi Gao, Lei Yan, Hongying Zhao institute of remote sensing & geographic information system, peking university beijing Key Lab of Spatial information Integration & Its Application. beijing, 100871, china

Due to the affection of large moving object in the video image, the ordinary image stabilization algorithms can’t get precise motion vector of the image. In this paper, a new image stabilization method that explicitly deals with video images containing large moving object is given out. It detects a rough area containing moving object first. Then this area will be got rid of from source image. Finally, a feature area taken from the rest part is used to calculate the image motion. For the affection of moving object has been eliminated, motion vector’s precision of the image is improved greatly.

关键词： image stabilization moving object detection image processing

来源： cnki会议评论

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cnki会议

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计算机工程与应用 2002年第5期38卷 204-206页

作者：窦静晏磊常炳国北京大学遥感与地理信息系统研究所北京100871 北京市空间信息集成与3S工程应用重点实验室北京100871

开发了一个电子商务网站系统,用于在线冲印数字影像。在充分论证了几种电子商务解决方案优缺点基础上,详细分析了该系统的需求、实现功能,采用了目前通用的三层系统,应用服务器层采用iPlanet中间件技术。论文重点讨论iPlanet中间件技术... 详细信息

开发了一个电子商务网站系统,用于在线冲印数字影像。在充分论证了几种电子商务解决方案优缺点基础上,详细分析了该系统的需求、实现功能,采用了目前通用的三层系统,应用服务器层采用iPlanet中间件技术。论文重点讨论iPlanet中间件技术的特征及其在电子商务系统应用中的优越性。

关键词：电子商务系统数字影像 iPlanet技术中间件

Loose architecture of multi-level massive geospatial data based on virtual quadtree

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Science china(Technological Sciences) 2008年第S1期51卷 114-123页

作者： YANG ChongJun,WU Sheng,REN YingChao,FU Li,ZHANG FuQing,WANG Gang,TAN Jian,LIU DongLin,MA ChaoJi & LIANG Li State Key Laboratory of remote sensing Science,Jointly Sponsored by the institute of remote sensing Applications of Chinese Academy of Sciences and beijing Normal university,beijing 100101,china 1. State Key Laboratory of remote sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

This paper proposed a virtual quadtree (VQT) based loose architecture of multi-level massive geospatial data for integrating massive geospatial data dispersed in the departments of different hierarchies in the same sector into a unified GIS (geographic information system) platform. By virtualizing the nodes of the quad-tree,the VQT separates the structure of data organization from data storage,and screens the difference between the data storage in local computer and in the re-mote computers in network environment. And by mounting,VQT easily integrates the data from the remote computers into the local VQT so as to implement seam-less integration of distributed multi-level massive geospatial data. Based on that mode,the paper built an application system with geospatial data over 1200 GB distributed in 12 servers deployed in 12 cities. The experiment showed that all data can be seamlessly rapidly traveled and performed zooming in and zooming out smoothly.

关键词： massive geospatial data virtual quadtree loose architecture

基于WebGIS的土壤侵蚀模型的研究及应用

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水土保持学报 2001年第3期15卷 52-55页

作者：刘海涛秦其明北京大学遥感与地理信息系统研究所，北京100871

土壤侵蚀是一个世界性的环境问题 ,它使土壤的生产力和用水的质量降低 ,从而引起土壤沉积并增加了发生洪涝灾害的可能性。随着世界范围内土壤侵蚀的日益严重以及水土流失问题的突出 ,土壤侵蚀的研究越来越深入。但目前对土壤侵蚀的工作... 详细信息

土壤侵蚀是一个世界性的环境问题 ,它使土壤的生产力和用水的质量降低 ,从而引起土壤沉积并增加了发生洪涝灾害的可能性。随着世界范围内土壤侵蚀的日益严重以及水土流失问题的突出 ,土壤侵蚀的研究越来越深入。但目前对土壤侵蚀的工作大多局限在模型的改进和其相关因子的选择上 ,缺乏一个良好的用户界面来完成土壤侵蚀模型各个因子以及土壤侵蚀预测结果的分析与其可视化。通过充分利用 GIS的有关技术 ,建立了一个基于 USL E的网络土壤侵蚀模型 ,并设计了应用界面 ,解决了上述问题。试验表明 :这个基于 WEBGIS的土壤侵蚀模型 ,不仅使土壤侵蚀研究成果通过 GIS的良好界面表现出来 ,而且还可以利用 GIS的有关分析工具 ,反过来促进土壤侵蚀模型的改进。

关键词：土壤侵蚀模型 WEBGIS USLE