2008/9/15fuzzy set theory chap01.ppt1 Introduction to Fuzzy Set Theory

2008/9/15fuzzy set theory chap01.ppt2 Uncertainty Information –Meaningful data –Knowledge get from experience Uncertainty –The condition in which the possibility of error exist Complexity

2008/9/15fuzzy set theory chap01.ppt3 Possibility and Probability Possibility –The degree that thing happens Probability –The probability that things be happen or not Poison ?

2008/9/15fuzzy set theory chap01.ppt4 Measurement and Uncertainty Precision –No matter how accurate our measurements are, some uncertainty always remains –Fractional parts Measure ?

2008/9/15fuzzy set theory chap01.ppt5 Language and vagueness Understanding of word meaning –Full texture of cultural and personal association –Vagueness Heap paradox Quantitative method for taking into account of vagueness Taking a stone from a heap, it leaves a heap

2008/9/15fuzzy set theory chap01.ppt6 The emergence of fuzzy set theory To deal with uncertainty –Avoid –Statistical mechanics –Fuzzy set (Zadeh in 1965) Crisp set –A collection of things –Boundary is require to be precise

2008/9/15fuzzy set theory chap01.ppt7 Fuzzy sets Definition –The pair of member and the degree of membership of the member Membership function

Fuzzy and crisp 180cm179cm cm Degree of high Fuzzy 1 cm Degree of high 180 Crisp 1

2008/9/15fuzzy set theory chap01.ppt9 Applications Pattern recognition and clustering Fuzzy control –Automobiles, air-condition, robotics Fuzzy decision –Stock market, finance, investment Expert system –Database, information retrieval, image processing Combined with other field –Neural network, genetic algorithms