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The traditional methods used so far for modeling, analysis and control of systems are generally based on determining the differential equations governing the system and the designing based on some mathematical methods and algorithms. Recent investigations and studies show that, with the use of some approximations, the most complicated systems can easily be analyzed and controlled without actually being involved I n a sophisticated computation or on exact mathematical model. In systems made by man, the efforts in implementing methods similar to Ruman reasoning is the basis of
introducing the expert control systems and
the artificial intelligence. In this paper, the qualitative control is introduced as one of the recent methods of achieving this objective, the nature of qualitative reasoning, its applications and advantages are discussed and compared with the fuzzy control, which is one of commonly used methods in artificial intelligence.