Page 312 - Electrical Engineering Dictionary
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linguistic models. A typical example is con-  Seealsoconvexfuzzyset, fuzzysingleton.
                              trol of dynamic systems based on dynamic
                              fuzzy models, which consist of a number
                              of local linear models smoothly connected  fuzzy observer  a device to estimate the
                              through a set of nonlinear membership func-  states of a dynamic system, involving fuzzy
                              tions.                                 logic concepts. A typical example is an ob-
                                                                     server constructed from a number of local
                              fuzzy modeling  combination of available  observers through fuzzy membership func-
                              mathematical description of the system dy-  tions.
                              namics with its linguistic description in terms
                              of IF-THEN rules. In the early stages of  fuzzy operator  logical operator used on
                              fuzzy logic control, fuzzy modeling meant  fuzzy sets for fuzzy reasoning. Examples are
                              just a linguistic description in terms of IF-  the complement (NOT), union (OR), and the
                              THEN rules of the dynamics of the plant  intersection (AND).
                              and the control objective.  Typical exam-
                              ples of fuzzy models in control application
                                                                     fuzzy optimal control  optimal control in-
                              includes Mamdani model, Takagi–Sugeno–
                                                                     volving fuzzy logic concepts or fuzzy control
                              Kang model, and fuzzy dynamic model.
                                                                     to achieve an optimal control performance in-
                                                                     dex.
                              fuzzyneuralcontrol  acontrolsystemthat
                              incorporates fuzzy logic and fuzzy inference
                                                                     fuzzy optimal filter  optimal filter involv-
                              rules together with artificial neural networks.
                                                                     ing fuzzy logic concepts or fuzzy filter to
                                                                     achieve an optimal filter performance index.
                              fuzzy neural network  artificial neural
                              network for processing fuzzy quantities or
                                                                     fuzzy OR   See triangular co-norm.
                              variables with some or all of the following
                              features: inputs are fuzzy quantities; outputs
                              are fuzzy quantities; weights are fuzzy quan-  fuzzy output feedback  fuzzy control
                              tities; or the neurons perform their functions  based on feedback of a plant output. This
                              using fuzzy arithmetic.                is closely related to fuzzy dynamic models.

                              fuzzy neuron  a McCulloch–Pitts neuron  fuzzy parameter estimation  a method
                              with excitatory and inhibitory inputs repre-  that uses fuzzy interpolation and fuzzy ex-
                              sented as degrees between 0 and 1; output is  trapolationtoestimatefuzzygradesinafuzzy
                              a degree to which it is fired.          search domain based on a few cluster center-
                                                                     grade pairs. An application of this method is
                              fuzzy nonlinear control  nonlinear con-  to estimate mining deposits.
                              trol involving fuzzy logic concepts or fuzzy
                              control with application to nonlinear sys-  fuzzy partition  partition of a plant oper-
                              tems.                                  ating space based on fuzzy logic concepts. A
                                                                     typical example is a partition of a state space
                              fuzzy number   a convex fuzzy set of the  by overlapping subspaces which are charac-
                              real line such that                    terized by a set of fuzzy membership func-
                                1. it exists exactly one point of the real line  tions.
                              with membership 1 to the fuzzy set;
                                2. its membership function is piecewise  fuzzy pattern matching  a pattern match-
                              continuous.                            ing technique that applies fuzzy logic to deal
                                In fuzzy set theory, crisp (nonfuzzy) num-  with ambiguous or fuzzy features of noisy
                              bers are modeled as fuzzy singletons.  point or line patterns.



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