In the present paper,the risk assessment of disasters induced by typhoons in Shandong Province has been carried out based on the basis of the analyses of the historical data during 1985-2010.In order to reduce the imp...In the present paper,the risk assessment of disasters induced by typhoons in Shandong Province has been carried out based on the basis of the analyses of the historical data during 1985-2010.In order to reduce the impact of the social and economic development status on the evaluation results in various periods,the normalized evaluation method was used to analyze the annual typhoon-induced damage in the concerned period.The quantitative comprehensive index is proposed with fuzzy mathematics,and the effect of typhoon-induced disasters is systematically investigated with the proposed index.In the analyses of the various hazard factors,the damage induced by the typhoon is combined with human and social factors,and further is comprehensively analyzed based on a GIS platform.The assessment results indicate that the normalized damage induced by typhoons presents the downward trend year by year and regional differences with significant temporal-spatial characteristics.The results of the present study are expected to be beneficial to disaster prevention and mitigation in Shandong Province.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
文摘In the present paper,the risk assessment of disasters induced by typhoons in Shandong Province has been carried out based on the basis of the analyses of the historical data during 1985-2010.In order to reduce the impact of the social and economic development status on the evaluation results in various periods,the normalized evaluation method was used to analyze the annual typhoon-induced damage in the concerned period.The quantitative comprehensive index is proposed with fuzzy mathematics,and the effect of typhoon-induced disasters is systematically investigated with the proposed index.In the analyses of the various hazard factors,the damage induced by the typhoon is combined with human and social factors,and further is comprehensively analyzed based on a GIS platform.The assessment results indicate that the normalized damage induced by typhoons presents the downward trend year by year and regional differences with significant temporal-spatial characteristics.The results of the present study are expected to be beneficial to disaster prevention and mitigation in Shandong Province.
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^＋.
