The Restricted Language Architecture of a Hybrid Representation System

Abstract

Hybrid architectures hatJe been used in setJeral recent knowledge representation systems . This paper explores some distinctions between tJarious hybrid representation architectures , focusing in particular on systems built around restricted representation languages . This restricted language architecture is illustrated by describing KL-TWO, a hybrid reasoner based on the restricted representation facility RUP. The bulk of this paper discusses KLTWO, its subcomponents, and the techniques used to interface them. Many recent knowledge representation systems have been based on hybrid architectures . These systems are hybrids in that they do not attempt the entire knowledge representation task with a single inferential component . Instead, they combine several reasoners into a complex whole. The advantages to be gained by this hybrid approach vary from system to system , but often include increases in the system 's computational efficiency, the coverage of its representation language, or the ease of expressing knowledge with the system. The topic of this paper is a new logic-based hybrid representation system. This system, called KL-TWO, is one which I have been developing with my colleagues over the past two years. Although KL-TWO has features in common with other hybrid reasoners, it differs very significantly from other systems in the way the common features are used . The purpose of this paper is thus twofold: to describe the features that KL-TWO possesses , and to ~tress the differences in approach between KL-TWO and other hybrid reasoners .