Retrieval-By-Unification Operation on a Relational Knowledge Base
Yukihiro Morita, Haruo Yokota, Kenji Nishida, Hidenori Itoh · Tokyo Tech Research Repository (Tokyo Institute of Technology) · 1986
This paper describes a method for retrieval-byunification (RBU) operations, especially unificationjoin, on a relational knowledge base. The relational knowledge base is a conceptual model for a knowledge base. In this model knowledge is represented by term relations. Terms in the term relations are retrieved with operation called RBUs (i.e., unification-join and unification-restriction). To perform unification-join in the simplest manner, all possible pairs of tuples in term relations should be checked to see if each pair of terms in the tuples is unifiable or not. This would result in an extremely heavy processing load. We propose a method which involves ordering terms and, as result, omitting some pairs from this processing. The paper also describes a method for implementing the unificaiion engine (UE), that is, hardware dedicated to the RBU operations.