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针对管网信息系统中的三维空间对象一管网，提出了一种基于固定三维网格划分的八叉树空间索引机制，称为Ｏｃｔｒｅｅ；并提出了一种层次分明的编码方法，有效地存储和管理数目庞大的八叉树结点。为了进一步缩小空间查询检索操作的范围，引入了面向类对象的二级查询技术，有效地提高了城镇管网信息系统ＵＰＮＩＳ（ＵｒｂａｎＰｉｐｅｌｉｎｅＮｅｔｗｏｒｋＩｎｆｏｒｍａｔｉｏｎＳｙｓｔｅｍ）的性能。
In view of the pipe network of 3D space object in pipe network information system, an octree spatial indexing mechanism based on fixed 3D mesh is proposed, which is called Octree. And a hierarchical coding method is proposed to effectively store And manage a large number of octree nodes. In order to further reduce the scope of spatial query and retrieval operations, a class-oriented second-level query technology is introduced to effectively improve the performance of Urban Pipeline Network Information System (UPNIS).