The expert system has proven itself to be a valuable aid in diagnosing and treating problems in domains requiring expertise. The commercial world has been alerted to this fact and the thrust is to make the expert system portable and available on small computers.

The goal of this research has been to lay the groundwork for a domain independent expert system builder on a microcomputer. The result of this effort was CIEGEN, a system consisting of a rule compiler, inference engine, and rule generator developed on the IBM PC. It is domain independent, responsible for transforming a knowledge base of rules into heuristic based decision trees, and capable of performing backward chaining consultations.

The system is also heuristic independent, allowing a knowledge base to be compiled by different heuristics and compared using the log created by the inference engine. A subgoal of the development of CIEGEN has been to study the heuristics used to compile a knowledge base because the efficiency of the expert system is based on the intelligence of the heuristic. The heuristic used by EMYCIN was implemented and compared with a heuristic developed by the author. For the six types of knowledge based generated by CIEGEN's rule generator, EMYCIN's heuristic, on the average, executed more quickly.


Computer Science


This report is substantially the M.S. thesis of the first author, completed July, 1984.

Report Number


Document Type

Technical Report

Document Version

Final Version

File Type





© 1984 University of Missouri--Rolla, All rights reserved.

Publication Date

July 1984