4th International FLINS Conference on Intelligent Techniques and Soft Computing in Nuclear Science and Engineering, BRUGGE, Belgium, 28 - 30 August 2000, pp.289-296
Our objective in this paper is to model and reduce inconsistency in expert knowledge for our proposed 2-way adaptive fuzzy system that makes use of intuitionistic fuzzy sets. Intuitionistic fuzzy sets model an interval valued distribution of information in the adaptive control architecture with the necessity at the lower bound as the degree of membership functions and the possibility at the upper bound as the complement of the degree of nonmembership functions. Uncertainty is modelled as the width of this interval. A width of zero is at the basis of a deterministic control. The use of intuitionistic fuzzy sets brings a flexibility in the system since it is possible to assign control upper bounds (nonmembership functions) independently from control lower bounds (the membership functions). There is only a consistency constraint on this assignment, which is that the sum of the two functions should be less than or equal to unity. However, in many control problems, this inequality constraint is not satisfied giving rise to inconsistency.