Great progresses have been made in the application of fuzzy set theory
and fuzzy logic. Most remarkable area of application is 'fuzzy control',
where fuzzy logic was first applied to plant control systems and its use
is expanding to consumer products. Most of fuzzy control systems uses
fuzzy inference with max-min or max-product composition, similar to the
algorithm that first used by Mamdani in 1970s. Some algorithms are
developed to refine fuzzy controls systems but the main part of
algorithm stays the same. Triggered by the success of fuzzy control
systems, other ways of applying fuzzy set theory are also investigated.
They are usually referred to as 'fuzzy expert sys- tems', and their
purpose are to combine the idea of fuzzy theory with AI based approach
toward knowledge processing. These approaches can be more generally
viewed as 'fuzzy information processing', that is to bring fuzzy idea
into informa- tion processing systems.