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云首水库设计年径流计算 被引量:1
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作者 栗雪峰 张泽中 +1 位作者 高同喜 高同美 《华北水利水电大学学报(自然科学版)》 2014年第3期15-18,共4页
为确定规划中无径流资料的云首水库工程规模,需要分析计算设计年径流量及年内分配.采用地理综合法计算了云首水库坝址以上控制流域年径流的均值、变差系数和偏态系数,获得了该流域在丰水年(P=20%)、平水年(P=50%)、枯水年(P=75%)和特枯... 为确定规划中无径流资料的云首水库工程规模,需要分析计算设计年径流量及年内分配.采用地理综合法计算了云首水库坝址以上控制流域年径流的均值、变差系数和偏态系数,获得了该流域在丰水年(P=20%)、平水年(P=50%)、枯水年(P=75%)和特枯水年(P=95%)的设计年径流量分别为2 393,1 198,654,318万m3.采用水文比拟法确定了年内分配.研究表明,采用地理综合法计算年径流的均值、变差系数和偏态系数,采用水文比拟法确定年内分配,可作为无资料地区年径流合理分析计算的方法组合. 展开更多
关键词 设计年径流量 径流年内分配 地理综合法 水文比拟法
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Problems of Integrated Assessment of Geo-ecosystems of Steppe Zone of Ural River Basin
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作者 Nurgul Ramazanova Gulzhan Dzhanaleyeva 《Journal of Environmental Science and Engineering(B)》 2012年第8期1037-1043,共7页
Methodological approaches to the assessment of natural geo-ecological systems are researched. Analysis of the interaction of natural and anthropogenic components of the geo-ecological systems and their management is b... Methodological approaches to the assessment of natural geo-ecological systems are researched. Analysis of the interaction of natural and anthropogenic components of the geo-ecological systems and their management is based on the consideration of natural-resource potential in the changing spatial and temporal connection. The principles of identifying and mapping of geo-ecological systems of various rank. Structural changes resulting from anthropogenic transformation allow establish the quality of geo-ecosystems and rank according to the degree of self-realization and sustainability. 展开更多
关键词 Geo-ecological system geo-ecological-resource potential NRP (natural-resource potential).
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On the Laws and Causes of Socio-economic Territorial Differentiation in Minority Areas in China
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作者 Xue Mei Dong Suocheng 《Chinese Journal of Population,Resources and Environment》 2009年第1期30-36,共7页
On the basis of applying quantitative and qualitative approaches as well as GIS technology, this paper established an index system to make a comprehensive evaluation on socio-economic development of minority areas in ... On the basis of applying quantitative and qualitative approaches as well as GIS technology, this paper established an index system to make a comprehensive evaluation on socio-economic development of minority areas in China. The result showed that socio-economic development in minority area presents a series of characteristics that the north is high and the south is low, center-margin pattern is obvious and the areas with middle and lower development indices are distributed centrally and continuously. However, the causes of the socio-economic characteristics mainly include natural conditions, economic development basic, population cultural quality, re-gional combination and development conditions of mineral and energy resources, informal institutional factors and distribution of major traffic lines.. 展开更多
关键词 minority areas socio-economic development laws of territorial differentiation
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Research on Holistic Index Method of Geography Markup Language
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作者 ZHANG Haitao YUAN Lifeng JIANG Jie 《Geo-Spatial Information Science》 2009年第4期251-256,共6页
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
关键词 GML extend region code semantic-spatial query
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