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Fuzzy Inference and Reasoning. Proposition. Logic variable. Basic connectives for logic variables. (1) Negation (2) Conjunction. Basic connectives for logic variables. (3) Disjunction (4) Implication. Logical function. Logic Formula . Tautology. Tautology. Predicate logic.
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Basic connectives for logic variables (1) Negation (2) Conjunction
Basic connectives for logic variables (3) Disjunction (4) Implication
Fuzzy Propositions • Assuming that truthandfalsity are expressed by values 1 and 0, respectively, the degree of truth of each fuzzy proposition is expressed by a number in the unit interval [0, 1].
Fuzzy Propositions p : V is F is S • V is a variable that takes values v from some universal set V • F is a fuzzy set onVthat represents a fuzzy predicate • S is a fuzzy truth qualifier • In general, the degree of truth, T(p), of any truth-qualified proposition p is given for each v e V by the equation T(p) = S(F(v)).
Representation of Fuzzy Rule Single input and single output Multiple inputs and single output Multiple inputs and Multiple outputs
Representation of Fuzzy Rule Multiple rules
Compositional rule of inference The inference procedure is called as the “compositional rule of inference”. The inference is determined by two factors : “implication operator” and “composition operator”. For the implication, the two operators are often used: For the composition, the two operators are often used:
Representation of Fuzzy Rule Max-min composition operator Mamdani: min operator for the implication Larsen: product operator for the implication