Logical Interpretation of Fuzzy Control
In spite of the appearance there are several difficulties to give a rigorous logical interpretation of the IF-THEN rules. As an example, interpret a rule as IF (temperature is "cold") THEN (heater is "high") by the first order formula Cold(x)→High(y) and assume that r is an input such that Cold(r) is false. Then the formula Cold(r)→High(t) is true for any t and therefore any t gives a correct control given r. A rigorous logical justification of fuzzy control is given in Hájek's book (see Chapter 7) where fuzzy control is represented as a theory of Hájek's basic logic. Also in Gerla 2005 a logical approach to fuzzy control is proposed based on fuzzy logic programming. Indeed, denote by f the fuzzy function arising of a IF-THEN systems of rules. Then we can translate this system into fuzzy program in such a way that f is the interpretation of a vague predicate Good(x,y) in the least fuzzy Herbrand model of this program. This gives further useful tools to fuzzy control.
Read more about this topic: Fuzzy Control System
Famous quotes containing the words logical, fuzzy and/or control:
“Revolution
Is the affair of logical lunatics.”
—Wallace Stevens (18791955)
“Even their song is not a sure thing.
It is not a language;
it is a kind of breathing.
They are two asthmatics
whose breath sobs in and out
through a small fuzzy pipe.”
—Anne Sexton (19281974)
“In Vietnam, some of us lost control of our lives. I want my life back. I almost feel like Ive been missing in action for twenty-two years.”
—Wanda Sparks, U.S. nurse. As quoted in the New York Times Magazine, p. 72 (November 7, 1993)