Ontologies and knowledge representation

Computer systems depend more and more on the use of declarative knowledge based systems (KBS) and ontologies. We present a system, called RIO (for object-oriented intermediate representation), to represent ontologies. The RIO formalism implements various notions taken from the diversity of the knowledge involved and the effort to achieve a reliable system. It has two objectives: 1) to represent conceptual abstractions, called concepts, that can be defined by intension; 2) to organise these concepts according to the relationship between them with emphasis on the relationship of generalisation-specialisation with precisely defined inheritance semantic. We also present a basic language, called the binary-relation system. Its goal is to allow the sharing of KBS and in particular RIO ontologies. It is based on the manipulation of binary relations, which provides many advantages. It allows the definition of new knowledge representation systems, as RIO, and also plays an interlingua role for knowledge base exchanges. Furthermore, it permits a satisfactory formalisation of object-oriented systems