The Role of Expert Systems Technology in Design

Using a scenario format, this paper first reviews the nature of chemical process design, showing that designers quickly make major decisions with minimal information and constantly revise their strategy to solve a problem. To automate this activity on a computer will require models of the process being created at several levels of abstraction as well as models that capture the beliefs of the modeler about the abilities of himself, others and the aids available and models of strategies for complex problem solving. The second section of the paper extensively reviews current expert system concepts, illustrating each of them with design examples. It is argued that expert systems are knowledge based. The authors describe many of the control strategies used in today's systems, and also consider different problem representations - rules, logic and frames - and indicate when each might be preferred. The last section presents the authors views on what will be involved in creating a future expert system for desig