【摘要】 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。更多还原

【Abstract】 Because the pipelines in UPNIS are three-dimensional spatial objects, this paper presents the octree based on fired-gridsspatial index mechanism and an encoding method which has clear hierarchy and is efficient in storing and managing the crunodes of octreewhose number is so large. In order tO reduce ulteriorly retrieving range for spahal information query and to raise query speed, the retrievingtechnology oriented class objectS in two levels is presented. It improves the performance of UPNIS.更多还原