基于实体对象树FOOT模型和四层体系结构的GIS方法研究

The Method of GIS Platform Based on Feature-oriented Object Tree(FOOT) and Four Tier Architecture

提出了面向地理空间实体对象树模型 (FOOT) ,首先重点讨论了空间分区、空间聚簇、空间索引 ,然后分析了四层结构设计中的数据库服务层、应用接口层、应用层相关技术。基于所提出的空间数据组织方法和系统结构 ,介绍了具有海量空间数据管理的系统功能模块 ,并提供了详细的对象逻辑关系说明。同时在对 FOOT模型和系统实现的关键技术进行设计的基础上 ,给出了一个基于 L inux操作系统和 Oracle数据库的分布式海量空间数据处理平台实例。采用 30 GB的空间数据测试结果表明 ,系统实现了面向实体的空间数据组织、统一的海量空间数据管理以及分布式空间数据计算等主要目标。该系统用于对全国 1∶ 4 0 0万土地利用图、1∶ 4 0 0万市县行政图数据上载的试验表明 ,不仅显示速度较快 ,且图形裁剪、空间叠加、缓冲分析等效率较高 ,验证了 FOOT模型的正确性、有效性、合理性。

A geo-spatial data model of feature-oriented object tree (FOOT) is presented. Spatial partitioning, spatial clustering and spatial indexing were emphatically discussed. Database services, application interface and application services in Four Tier Architecture are analyzed. By the spatial data organization and systematic architecture, function modules with massive spatial database management for the system are introduced. And also detailed object logic relation for the modules were explained. At last, on the base of design for the FOOT model and key technique of systematic implementation, an example of massive spatial database platform running in Linux and Oracle was given. The testing with 30 GB spatial data shows that the systematic main aims implement in feature-object spatial data organizing, integrative massive spatial data management and distributed spatial data computing. By the uploading national land use map and national county-administration map of 1∶400, the display is rapid. the efficiency of map windowing, spatial overlaying and buffer analyzing are very high, which validates the correctness, validity and rationality of FOOT.