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Title: An approach to the design of expert systems for hard real-time applications
Author: Jones, A. V.
Awarding Body: University College of Swansea
Current Institution: Swansea University
Date of Award: 1995
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Over recent years there has been considerable interest in the use of new programming techniques, derived from artificial intelligence (AI) research, in computer control. The reason for considering these techniques is the ever-growing desire for competitiveness in manufacturing and process plants. Two particularly important techniques to have emerged from AI research are expert systems and neural networks. In parallel with the growing need for efficiency, has been the desire to improve the safety and reliability of computer controlled systems. Achieving this requires that any software in the system must have reliable real-time performance - that is, it must produce results which are correct and on time. While progress is being made towards this end in the field of conventional software, the emergence of AI techniques is creating a new set of problems. This thesis examines the reasons why reliable AI systems must be developed, and highlights the differences between AI techniques and more-traditional programming methods. It is argued that true real-time performance can only be obtained from a resource-adequate system and that a state-based approach offers considerable advantages for a real-time expert system. An architecture is proposed which will provide the basis for developing expert systems for hard real-time applications. To overcome the predictability problems normally associated with the inference engine of an expert system, a knowledge-base compiler is presented which produces, from an expert-system ruleset, a procedural function with a known execution time. To validate this approach, a case study is presented in which an expert system has been developed for the control of a aircraft during landing. This example demonstrates the use of a rule-based expert system in a hard real-time environment. An evaluation of the ideas presented is given which identifies some of the limitations of the techniques discussed.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available