Forward-chaining rule systems must test each newly asserted fact against a collection of predicates to find those rules that match the fact. Expert system rule engines use a simple combination of hashing and sequential search for this matching. We introduce an algorithm for finding the matching predicates that is more efficient than the standard algorithm… (More)
<italic>In this paper, we propose a data structure, the Point-Range Tree (PR-Tree), specifically designed for indexing intervals. With the PR-Tree, a point data can be queried against a set of intervals to determine which of those intervals overlap the point. The PR-tree allows dynamic insertions and deletions while it maintains itself balanced. A balanced… (More)
In this paper, we propose a design for the integration of a production rule system into an object-oriented database system. We put an emphasis on the rule system, and propose a pattern matching algorithm based on a discrimination network. A detail methodology for constructing a discrimination network for different types of rule conditions is presented.