The Framework of Knowledge Representation and Its Retrieval in LGS - Literature Guide System

Abstract

This paper describes the framework of knowledge representation a nd the te c hniqu e s for information retrieval in a program called LGS (the Literature Guide Syst e m). LGS will answe r questions about scientific literatures in natural language, Model theoreti c approach is employed to represent the meanings of senten c es in the abstra c t s of literatures. The knowledge base is a set of interpreted logi c al formulas, and is partitioned into possible worlds. User's own view to the knowl e dge base can be incorporated into obje c ts called script frames. A script frame is defined in terms of lo g ical formulas. A query to the knowledge base is presented as a pattern. A list containing all items whi ch match the pattern will be returned as the result, A set of rules for pattern mat c hing a re defined in terms of logic, and are designed so as to cover the cases of paraphras e s and categorical implications. LGS is composed of an accommodator, a retriever, and a natur al language interface. It is under development on the personal LISP system.