Selective Evaluation of Nodes in a Tree-Based Expert System
Original Publication Date: 1987-Apr-01
Included in the Prior Art Database: 2005-Feb-01
The most common form of knowledge representation in an expert system is the production rule. The production rule is nothing more than an IF- THEN statement. If the conditions in the IF part of the rule are met, then and only then is the action or conclusion in the THEN part of the rule taken. For example: IF: (1) the printer is suspected, AND (2) the printer test has failed, OR (3) the printing is bad, THEN install a new printer element. The Portable Inference Engine (PIE) is an expert system with a tree-based knowledge base. The IF-THEN concept was added to the tree structure in the form of a node with two and optionally three sons.