EXPERT SYSTEM FOR ACTUATED CONTROL OF TRAFFIC AT ISOLATED INTERSECTIONS (EXACT) .1. KNOWLEDGE ACQUISITION AND REPRESENTATION

This paper describes the application of expert systems in traffic-actu ated control at isolated signalized intersections. The expert system E XACT (EXpert system of ACtuated control for Traffic at isolated inters ections) was developed to assist traffic engineers in selecting the ap propriate type of traffic-actuated controller and its associated featu res, the type of detector and its configuration, and time settings at a particular intersection. EXACT was structered to handle both design and operational problems. The first steps of EXACT's development, incl uding variable identification, shell selection, knowledge acquisition, and knowledge representation, are presented in detail in this paper.