A Reference Framework for Integrating Multiple Representations of Geographical Maps

摘要

Geographical maps can be represented and manipulated using different data models, each dealing with different map properties: geometrical properties, describing the shape, extension and location of the objects composing the map, combinatorial properties, interpreting the map as a set of disjoint elements satisfying a certain set of combinatorial constraints, and topological properties, describing the topolog-ical relationships existing among map objects. These different representations (that we call layers) are typically supported in most geographical database management systems. However, all existing systems are downward closed, meaning that if some information A is contained in the combinatorial (topological) layer, the information required to compute A must be contained in the geometrical (combinatorial/geometrical) layer. Several applications do not require this closure. Rather, they can benefit from the incomplete representation of the map. The aim of this paper is the definition of a reference framework for integrating various and possibly incomplete representations of geographical .maps.