Syntactic Analysis for Natural Language Interfaces - the Integrated Deductive Approach

The objective of our research is the implementation of a German natural language interface for a deductive database system which models a production planning and control system. By means of our approach we suggest a way to overcome the severe drawbacks of interfaces that are designed as loosely coupled filters only. We integrate the interface into the database system itself, that is, the complete natural language analysis is done by the powerful logic language supplied by deductive databases. The paper focuses on the current state of work, the syntactic analysis. Since we had built up a powerful hierarchical dictionary for morphological and lexical analysis, we chose Categorial Unification Grammar (CUG) as theoretical framework of our prototype. Furthermore, the application of a bottom-up parsing strategy makes it possible to analyse also incomplete sentences in an easy and natural way. We extended CUG to deal with the free word order of the German language. We achieved a compact grammatical representation scheme which was applied to the implementation of an efficient parser within the deductive database system.