D. F-Logic Primer

Abstract

As discussed in Section 3.4.3, F-Logic is a knowledge representation language based on first-order predicate calculus and frames. F-Logic is a deductive, object-oriented database language. In this appendix we introduce only a subset of F-Logic as our approach should be independent of the representation language and its special features. For example, we did make no use of built-in features such as string handling, type conversion, method overloading or access to databases. More detailled introductions to F-Logic are available [133, 96]. This chapter is organized as follows: first of all we briefly introduce the syntax of F-Logic based on the basic alphabet of the language. Then we briefly show how classes and their signatures are described. Besides, we describe how facts of an ontology can be represented with objects. Finally, we outline how inferencing rules and queries are written in F-Logic.