Defuzzification with Constraints

  • Ronald R. Yager
  • Dimitar P. Filev
Part of the Theory and Decision Library book series (TDLD, volume 16)


We look at the problem of defuzzification in situations where in addition to the usual fuzzy output of the controller there exists some ancillary restriction on the allowable defuzzified values. We provide two basic approaches to address this problem. In the first approach we enforce the restriction by selecting the defuzzified value through a random experiment in which the only values which have nonzero probabilities are in the allowable region, this method makes use of a nonmonotonic conjunction operator. In the second approach we convert the problem to one of constraint optimization.


Membership Function Fuzzy Logic Controller Fuzzy Subset Nonlinear Programming Problem Output Space 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 1995

Authors and Affiliations

  • Ronald R. Yager
    • 1
  • Dimitar P. Filev
    • 1
  1. 1.Machine Intelligence InstituteIona CollegeNew RochelleUSA

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