Fuzzy relation-based diagnosis

Consideration was given to restoration of causes (diagnoses) from the observed effects symptoms) on the basis of fuzzy relations and the Zadeh composition inference rule. An approach was proposed to the design of the fuzzy diagnostic systems enabling solution of the fuzzy logic equations hand in hand with the construction and adjustment of the fuzzy relations on the basis of the expert-experimental information. Adjustment lies in selecting the membership functions of fuzzy causes and effects, as well as the fuzzy relations minimizing the difference between the model and experimental results of diagnosis. Optimization relies on the genetic algorithm. The proposed approach was illustrated by a computer experiment and an actual example of diagnosis.