DEVELOPMENT OF A COPILOT-TYPE EXPERT SYSTEM FOR THE VORTAC

UNDER PREVIOUS IN-HOUSE AND SMALL BUSINESS INNOVATION RESEARCH PHASES I AND II FUNDING, THE AUTHORS HAVE DEVELOPED AN EXPERT SYSTEM, COPILOT, FOR USE IN NUCLEAR POWER PLANT CONTROL ROOMS AS AN AID TO PLANT OPERATORS IN THE ONLINE DIAGNOSIS OF PLANT MALFUNCTIONS AND IN DECISION SUPPORT. THIS SYSTEM IS INNOVATIVE IN ITS KNOWLEDGE REPRESENTATION SCHEMA, WHICH IS BUILT AROUND BAYESIAN PRINCIPLES, ITS EXPLICIT AND CORRECT TREATMENT OF UNCERTAINTY, AND ITS ABILITY TO HANDLE "TRAJECTORY TYPE," TIME-DEPENDENT INSTRUMENT READINGS AS ITS PRIMARY SOURCE OF EVIDENTIARY INFORMATION. THE SYSTEM IS WELL SUITED TO TRAINING APPLICATIONS, IS FLEXIBLE AND ADAPTABLE TO CHANGING CONDITIONS, AND CAN INCORPORATE THE EVIDENTIARY IMPACT OF HUMAN OPERATOR ACTIONS. THE SYSTEM IS "GROWABLE" IN THE SENSE THAT, AT EARLY STAGES OF DEVELOPMENT, THE SYSTEM IS ALREADY CAPABLE OF BEING USED AND PROVIDING VALUE. EACH NEW INCREMENT OF DEVELOPMENT ENHANCES ITS VALUE BY ENLARGING THE DIAGNOSTIC SCOPE OF THE SYSTEM WITHOUT REQUIRING CHANGES TO THE WORK ALREADY DONE. THE FAULT DIAGNOSIS/FAULT ISOLATION REQUIREMENTS OF THE MAINTENANCE CONTROL CENTER (MCC) ARE ANALOGOUS TO THOSE OF A NUCLEAR PLANT CONTROL ROOM. WE PROPOSE THEREFORE TO APPLY THE COPILOT APPROACH TO THE MCC. PRIMARILY, WHAT WILLBE REQUIRED IS THE DEVELOPMENT OF A KNOWLEDGE BASE IN THE COPILOT FORMAT FOR THE EQUIPMENT WHOSE FAULTS MCC WISHES TO DIAGNOSE. NOTWITHSTANDING THE CLOSE ANALOGY, NEW PROBLEMS IN MCC APPLICATIONS WILL BE ENCOUNTERED, REQUIRING NEW IDEASAND METHODS. THE COPILOT SOFTWARE MAY REQUIRE EXTENSION AND MODIFICATION. BECAUSE OF THE "GROWABLE" FEATURE, A USABLE PRODUCT SHOULD BE OBTAINED VERY EARLY IN THE PROJECT, ALLOWING THE FEDERAL AVIATION ADMINISTRATION (FAA) TO JUDGE AND GUIDE THE DEVELOPMENT OF FURTHER INCREMENTS.