拓扑关系是一种相对较弱的空间目标位置约束,已广泛应用于空间查询、分析和推理等实际应用中。本文主要研究IR2中两个线目标间拓扑关系的描述和区分方法,采用的基本思路是将两个线目标间的关系描述为若干个基本关系的组合。在拓扑关系描述和区分时,提出了具有不同分类能力的拓扑不变量,分别是：维数、分离数、交分量类型和交分量全序,并依次建立了相应的分类方法。分析发现,在IR2中的两个线目标间具有17种潜在的基本关系。其中的11种是描述复合线/线关系的基本构成单元。

Topological relations have been recognized to be very useful for spatial query,analysis and reasoning.This paper concentrates on the topological relations between two lines in IR2.The line of thought employed in this study is that the topological relation between two lines can be described by a combination of finite number of basic(or elementary) relations.Based on this idea,a hierarchical approach is proposed for the description and determination of basic relations between two lines,where the topological invariants,including dimension,the number of separates,type of components,and sequence of components in the intersection of two lines,are defined and utilized.Seventeen(17) basic relations are identified and eleven(11) of them form the basis for combinational description of a complex relation,which can be determined by a compound relation model.