In order to understand the 3D landscape with many h igh buildings in a city, the 2D GIS has to be extended to 3D GIS. The further de velopment of CyberCity has to include various applications of 3D scenes from the out...In order to understand the 3D landscape with many h igh buildings in a city, the 2D GIS has to be extended to 3D GIS. The further de velopment of CyberCity has to include various applications of 3D scenes from the outdoor scenes to the indoor ones. In thispaper, some key techniques, such as data management method and dynamicalvisualization method for the outdoor and the indoor scenes, are discussed.The indoor scene is compared with the outdoor one. The idea of integratedrepresentation of the outdoor and the indoor scenes in CyberCity GIS is discusse d.展开更多
An Oracle8i-based approach is proposed to manage the integrated databases oflarge CyberCity. This approach consists of three schemes: ① a special R+-tree index is designed toaccelerate spatial retrieving, in which th...An Oracle8i-based approach is proposed to manage the integrated databases oflarge CyberCity. This approach consists of three schemes: ① a special R+-tree index is designed toaccelerate spatial retrieving, in which the bounding boxes of local regions have no intersection andall leaf nodes of the R+-tree (geometry records ) have no repetition; ② different data compressionalgorithms are adopted to compress the digital elevation models, 3D vector models and images, suchas LZ77 lossless compression algorithm for compression of vector data and JPEG compressionalgorithms for texture images; ③ in order to communicate with Oracle8i database, a CyberCity GIS.spatial database engine (SDE) is designed. On the basis of this SDE prototype a case study is done.展开更多
In this paper,the concepts about the CyberCity and the corresponding technique supports and typical applications are introduced.As the pilot projects,the applications of CCGIS software in CyberShenzhen and CyberShangh...In this paper,the concepts about the CyberCity and the corresponding technique supports and typical applications are introduced.As the pilot projects,the applications of CCGIS software in CyberShenzhen and CyberShanghai are also presented.At last,some of key technologies such as the reconstruction of three dimensional city model,vast amount of data integration and its real time application of 3D animation are discussed.展开更多
GeoStar is the registered trademark of GIS software made by WTUSM in China.By means of the GeoStar,multi_scale images,DEMs,graphics and attributes integrated in very large seamless databases can be created,and the mul...GeoStar is the registered trademark of GIS software made by WTUSM in China.By means of the GeoStar,multi_scale images,DEMs,graphics and attributes integrated in very large seamless databases can be created,and the multi_dimensional dynamic visualization and information extraction are also available.This paper describes the fundamental characteristics of such huge integrated databases,for instance,the data models,database structures and the spatial index strategies.At last,the typical applications of GeoStar for a few pilot projects like the Shanghai CyberCity and the Guangdong provincial spatial data infrastructure (SDI) are illustrated and several concluding remarks are stressed.展开更多
基金FundedbytheopenresearchfundprogramofLIESMARS (No .0 1 0 30 2 )
文摘In order to understand the 3D landscape with many h igh buildings in a city, the 2D GIS has to be extended to 3D GIS. The further de velopment of CyberCity has to include various applications of 3D scenes from the outdoor scenes to the indoor ones. In thispaper, some key techniques, such as data management method and dynamicalvisualization method for the outdoor and the indoor scenes, are discussed.The indoor scene is compared with the outdoor one. The idea of integratedrepresentation of the outdoor and the indoor scenes in CyberCity GIS is discusse d.
基金Project supported by the National Key Basic Research and Development Program (No. 2002CB312101) the National Natural Science Foundation of China (No.40001017).
文摘An Oracle8i-based approach is proposed to manage the integrated databases oflarge CyberCity. This approach consists of three schemes: ① a special R+-tree index is designed toaccelerate spatial retrieving, in which the bounding boxes of local regions have no intersection andall leaf nodes of the R+-tree (geometry records ) have no repetition; ② different data compressionalgorithms are adopted to compress the digital elevation models, 3D vector models and images, suchas LZ77 lossless compression algorithm for compression of vector data and JPEG compressionalgorithms for texture images; ③ in order to communicate with Oracle8i database, a CyberCity GIS.spatial database engine (SDE) is designed. On the basis of this SDE prototype a case study is done.
文摘In this paper,the concepts about the CyberCity and the corresponding technique supports and typical applications are introduced.As the pilot projects,the applications of CCGIS software in CyberShenzhen and CyberShanghai are also presented.At last,some of key technologies such as the reconstruction of three dimensional city model,vast amount of data integration and its real time application of 3D animation are discussed.
文摘GeoStar is the registered trademark of GIS software made by WTUSM in China.By means of the GeoStar,multi_scale images,DEMs,graphics and attributes integrated in very large seamless databases can be created,and the multi_dimensional dynamic visualization and information extraction are also available.This paper describes the fundamental characteristics of such huge integrated databases,for instance,the data models,database structures and the spatial index strategies.At last,the typical applications of GeoStar for a few pilot projects like the Shanghai CyberCity and the Guangdong provincial spatial data infrastructure (SDI) are illustrated and several concluding remarks are stressed.
