What is an Expert System

Knowledge-based expert systems (KBES) have created much excitement in the civil engineering computer user community. KBES evoke expectations of full-blown Artificial Intelligence (AI) systems: programs that adapt, learn, invent, and accumulate the combined wisdom of a profession. This paper presents the definition, role and impact of KBES in civil engineering. It is shown that most expectations of AI are largely premature. The second view is that many conventional algorithmic design application programs have always incorporated expertise in the form of limitations, assumptions, approximations, shortcuts, etc. The paper contrasts these programs to KBES in a number of dimensions, such as control, knowledge structure, and development process. The useful and practical KBES will be written by today's application programmers, once the KBES methodology is adopted as a component of their kit of tools.