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GIS中地理要素多尺度概念模型的初步研究 总被引:17,自引:3,他引:17
对地理要素的多尺度表达(多重表达)是当前多尺度空间数据库领域的研究热点之一。它可以为GIS用户提供由整体到局部、由抽象到具体的地理实体和地学过程的分析及可视化功能。其中要素的多尺度概念模型是解决该问题的基础和先决条件。本探讨了地理空间要素多尺度表达在几何层次、实体层次、属性层次方面的多尺度表现特征,与传统的GIS概念模型进行比较,研究了要素的多尺度概念数据模型设计所应满足的基本条件,提出了构建多尺度空间数据概念模型的关键策略,详细剖析了模型中地理要素在不同尺度下的抽象数据类型、属性值域的演变规律,以及要素不同尺度表达问的语义、层次连通、尺度关系等内在联系。并以城市地图要素为例,采用满足多重表达建模要求的扩展E—R建模方法,实现了对要素多尺度抽象表达的概念模型设计。 相似文献
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WANG Yan-hui MENG Hao LIU Xiao-meng 《中国矿业大学学报(英文版)》2006,16(4):494-499
As the problems of conceptual and representational differences will arise among multi-representations, inter-connectivity maintenance among multi-representations exists as a foundational task in building multi-scale data model. Since the existing methods are still not satisfactory in practice, the inter-connectivity among multiple representations can be only achieved if the multi-scale model is capable of explicitly inter-relating them and dealing with their differences. So, this paper firstly explores the relation among multiple representations from the same entity, such as multi-semantic, multi-geometry, multi-attributes, hierarchical semantic relations and so on. Based on these, this paper proposes aggregation-based semantic hierarchical matching rules (ASHMR) as the basis of tackling inter-connectivity among multi-representations, and defines the available hierarchical semantic knowledge, namely semantically equal, semantically related and semantically irrelevant. According to different change among multi-representations from different types of objects, the applications and techniques of the corresponding hierarchy inter-connectivity matching criterion are explored. And taken the road intersections as examples, a case in point is given in details for describing the strategies of inter-connectivity maintenance, showing that this method is feasible to deal with inter-connectivity. 相似文献
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