In GIS field, great varieties of information from different domains are involved in order to solve actual problems. But usually spatial information is stored in diverse spatial databases, manipulated by different GIS ...In GIS field, great varieties of information from different domains are involved in order to solve actual problems. But usually spatial information is stored in diverse spatial databases, manipulated by different GIS platforms. Semantic heterogeneity is caused due to the distinctions of conception explanations among various GIS implements. It will result in the information obtaining and understanding gaps for spatial data sharing and usage. An ontology-based model for spatial information semantic interoperability is put forward after the comprehensive review of progress in ontology theory, methodology and application research in GIS domain.展开更多
Currently, the OGC GML （Geography Markup Language） specification has been the de facto standard for GIS data sharing and exchanging and spatial interoperation. Adopting nested association expression approach of XML ...Currently, the OGC GML （Geography Markup Language） specification has been the de facto standard for GIS data sharing and exchanging and spatial interoperation. Adopting nested association expression approach of XML data, GML data documents can store both spatial information and semantic relationship information of geographical elements. To improve the efficiency of path query on GML two type information, the paper describes a holistic index method for GML data, which we call EKR^＋ （optimized R＋-tree base on Extend Region Code and K-means extent partition of GML feature elements）. The experiment results show that the efficiency of semantic-spatial query can be improved greatly by utilizing EKR^＋.展开更多
基金Supported by the National Natural Science Foundation of China （ No. 40601083 ）, the National Key Basic Research and Development Program of China （ No. 2004CB318206）.
文摘In GIS field, great varieties of information from different domains are involved in order to solve actual problems. But usually spatial information is stored in diverse spatial databases, manipulated by different GIS platforms. Semantic heterogeneity is caused due to the distinctions of conception explanations among various GIS implements. It will result in the information obtaining and understanding gaps for spatial data sharing and usage. An ontology-based model for spatial information semantic interoperability is put forward after the comprehensive review of progress in ontology theory, methodology and application research in GIS domain.
文摘Currently, the OGC GML （Geography Markup Language） specification has been the de facto standard for GIS data sharing and exchanging and spatial interoperation. Adopting nested association expression approach of XML data, GML data documents can store both spatial information and semantic relationship information of geographical elements. To improve the efficiency of path query on GML two type information, the paper describes a holistic index method for GML data, which we call EKR^＋ （optimized R＋-tree base on Extend Region Code and K-means extent partition of GML feature elements）. The experiment results show that the efficiency of semantic-spatial query can be improved greatly by utilizing EKR^＋.
