Page 308 - Electrical Engineering Dictionary

fuzzy approximation an action or pro- can be viewed as an inference process. For
cess of using a fuzzy system to approximate example, if an FCM’s trajectory starting from
a nonlinear function or mapping. an initial condition x(0) converges to an equi-
librium state A, then this can be interpreted
fuzzy associative memory a look-up ta- as the FCM providing an answer to a question
ble constructed from a fuzzy IF-THEN rule “What if x(0) happens?” In this sense it can
base and inference mechanism to define a re- be interpreted that the FCM stores the rule
lationship between the input and output of a “IF x(0) THEN the equilibrium A.” FCMs
fuzzy controller, or a fuzzy system. See also were introduced by B. Kosko.
fuzzy inference system.
fuzzy complement the complement of a
fuzzy automata based on the concept of fuzzy set A is understood as NOT (A).
fuzzysets, aclassoffuzzyautomataisformu-
lated similar to Mealy’s formulation of finite fuzzy concentration the concentration of
automata. a fuzzy set produces a reduction by squaring
the membership function of that fuzzy set.
fuzzy basis functions a set of fuzzy mem-
bership functions or their combinations in a fuzzy conditional statement an IF-
fuzzy system that form a basis of a function THEN statement of which either the an-
space, normally for function approximation. tecedents or consequent(s) or both may be
labels of fuzzy sets. Also know as fuzzy rule,
fuzzy behavioral algorithm a relational linguistic fuzzy model, linguistic rules. See
algorithm that is used for the specific purpose fuzzy IF-THEN rule.
of approximate description of the behavior of
a system. fuzzy control the application of fuzzy
logic and fuzzy inference rules utilizing
fuzzy C the C programming language in- knowledge elicited from human experts in
corporating fuzzy quantities and fuzzy logic generatingcontroldecisionsforthecontrolof
operations. processes. More specifically, a means of ex-
pressing an operator’s knowledge of control-
fuzzy c-means (FCM) a fuzzy version ling a process with a set of fuzzy IF-THEN
of the commonly used K-means clustering rules and linguistic variables.
algorithm. The main feature of FCM is that
a type of membership function is utilized in fuzzy control system stability stability of
computing a distance measure. Also called a fuzzy control system that normally includes
fuzzy ISODATA. a plant to be controlled and a fuzzy controller.

fuzzy clustering a method used to cluster fuzzy controller devices for implement-
data into subsets based on a distance or simi- ing fuzzy control, normally including the fol-
larity measure that incorporates fuzzy mem- lowing components: a fuzzifier to transform
bership functions. a crisp real-valued number to a fuzzy set; a
fuzzy rule base to define IF-THEN control
fuzzy cognitive map (FCM) nonlinear rules; a fuzzy inference engine to combine
dynamical systems whose state trajectories the IF-THEN rules; and a defuzzifier to trans-
areconstrainedtoresideintheunithypercube form a fuzzy set to a crisp real-valued num-
n
[0, 1] . The components of the state vector ber.
of an FCM stand for fuzzy sets or events that
occur to some degree and may model events, fuzzy controller design a process of
actions, goals, etc. The trajectory of an FCM determining a fuzzy controller including a

c
2000 by CRC Press LLC