Abstract

Multi-resolution or multi-scale spatial databases store and manage multiple representations of spatial objects in the same area, so consistency among multiple representations of the same objects should be evaluated and maintained. Although many approaches have been proposed to check inconsistencies in multi-resolution databases, there is still a lack of effective approaches working for complex objects, especially for regions with broad boundaries which is a general model for representing various types of uncertainties. This paper presents approaches for evaluating structural and topological consistency among multiple representations of complex regions with broad boundaries (CBBRs) based on map generalization operators: merging, dropping, and hybrid of these two. For evaluation of structural consistency, all possible multiple representations of a CBBR are generated automatically and organized into a structured neighborhood graph, and then correspondences and equivalences among the multiple representations are defined to determine whether two representations at different levels of detail are structurally consistent. For evaluation of topological consistency, the topological relations between all pairs of regions in two CBBRs are considered, and their variation with change of spatial scale is analyzed. Since the approaches in this paper are built on a hiearchical representation of CBBRs with arbitrarily complex structure, they will also work well for evaluating consistency among multiple representations of complex objects.

Keywords: Geographical information system; Complex regions with broad boundaries; Topological relations; The closest-structure-level graph; Consistency check

Article Outline

1. Introduction

2. Complex regions with broad boundaries and their hierarchical representations

3. Structural consistency of CBBRs in multi-resolution spatial databases

3.1. Structural correspondences and equivalences among multiple representations of CBBRs caused by the dropping operator

3.2. Structural correspondences and equivalences among multiple representations of CBBRs caused by the merging operator

3.3. Structural correspondences among multiple representations of CBBRs generated by the hybrid approach

3.4. Evaluation of structural consistency among multiple representations of CBBRs

4. Topological consistency of CBBRs in multi-resolution spatial databases

4.1. Dropping of regions

4.2. Merging of regions

4.3. Hybrid approach of merging and dropping operators

5. Discussion

Acknowledgements

References