Abstract
A computer language that allows both procedural and inferential programming was developed. In this language, an inference engine of first-order predicate calculus similar to Prolog was installed in a FORTH-like procedural language "The IntelligenT (TIT)." Hence one can execute the inferential treatment inside procedural routines. In addition, one can add procedural operation to the inference. This language was applied to rule-based control for a system with long dead time such as control of temperature of an air stream caused by natural convection. The rules are written as if-then expressions. Since these rules are not given by a procedural program but rather as a rule-base, their description and modification are quite easy. Satisfactory control was achieved by this rule-based controller.
