Expert systems are herein researched and discussed. Particular consideration is given to defining an expert system, describing how an expert system works, describing how an expert system is used, discussing the advantages of expert systems, and describing expert system applications in the medical care and petroleum production fields.
An expert system is defined as a computer software program that can do what an expert in a given field can do, and that incorporates the expertise of humans into a computer (Barker, 1990). An expanded definition of an expert system is that it is an application of the fundamental techniques of artificial intelligence in knowledge representation tasks through the use of computer systems to "help solve complex, real-world problems," and that are "strongly characterized by their use of large bodies of domain knowledge à gleaned from human experts, that have proved useful for solving typical problems in their domain" (Barr & Feigenbaum, 1987, p. 89). Artificial intelligence is a branch of computer science that is "concerned with designing intelligent computer systems à that exhibit the characteristics associated with intelligence in human behavior" (Barr & Feigenbaum, 1986, p. 4).
The development and use of expert systems proceeded much more slowly than the development and use of other types of software programming. Expert systems, however, are integral to computer-assisted decision-making systems (Harper, 1991). Expert systems are widely and successfully used as decision support in petroleum exploration, extraction, and refining (Harper, 1991).
An expert system is only as good as the human expertise it contains within it (Fichtelman, 1985). Although expert systems require the incorporation of human expert judgment criteria into their structure, however, human professionals from whom such expert judgment criteria must be obtained often resent providing such knowledge for machine applicat...