ABSTRACT
Since their introduction by Professor L. A. Zadeh in his seminal works (Zadeh, 1965, 1968, 1971, 1973, 1975) in the early 1970s, fuzzy sets and fuzzy logic theory have found a great variety of applications in control engineering, power systems, telecommunication, consumer electronics, information processing, pattern recognition, signal processing, machine intelligence, qualitative modeling, decision making, management, finance, medicine, the chemical industry, motor industry, robotics, and so on (see, e.g., Babuska, 1998; Bellman and Zadeh, 1970; Bezdek et al., 1999; Bonissone et al., 1995; Koska, 1992; Lee, 1990a,b; Mendel, 1995; Pedrycs, 1993; Sugeno, 1985; Teodorescu, Jain, and Kandel, 1998; Zimmermann, 1991). In particular, fuzzy logic control, or fuzzy control for short, as one of the earliest applications of fuzzy sets and fuzzy logic theory, has become one of the most notable applications. In fact, fuzzy logic control has proven to be a successful control approach to many practical and industrial systems, especially to complex nonlinear systems or even nonanalytic systems, and has been widely accepted as an alternative or complementary approach to conventional control techniques in many engineering applications.
