Rule-based spatial search

The application of applied artificial intelligence techniques to geographical data processing has attracted considerable interest in recent years as reflected in the research agendas of major GIS research institutions. This paper illustrates how a simple spatial problem, formalised using predicate calculus, may be readily implemented as a rule base in which the production rules represent Horn clauses. The theoretical significance of this exercise is the search for a high-level mathematical language capable of expressing, in a generic and implementation-independent syntax, the spatial relationships and queries typically handled by a GIS. Of more practical interest is the example it provides of mapping a conventional algorithm into a production rule knowledge structure.