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fuzzy expert systems and fuzzy reasoning

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[...]... tutorial and simplified real-world programs 1.1.4 Expert Systems for Fuzzy Control and for Fuzzy Reasoning There are two general types of fuzzy expert systems: fuzzy control and fuzzy reasoning Although both make use of fuzzy sets, they differ qualitatively in methodology Fuzzy process control was first successfully achieved by Mamdani (1976) with a fuzzy system for controlling a cement plant Since then, fuzzy. .. input and output restricted to numbers But the domain of fuzzy reasoning systems is not well defined; by definition, fuzzy reasoning systems attempt to emulate human thought, with no a priori restrictions on that thought Fuzzy control systems deal with numbers; fuzzy reasoning systems can deal with both numeric and non-numeric data Inputs might be temperature and pulse, where temperature might 38.58C and. .. keys, write and debug programs on the computer The theory of fuzzy mathematics is highly advanced; with the exception of fuzzy control systems, the theory behind fuzzy expert systems for other than numeric outputs is quite ill developed Much of the fuzzy expert systems theory in this book is original, and sometimes differs substantially from existing theory For fuzzy reasoning, as distinct from fuzzy control... with fuzzy expert systems, but not in the detail necessary to actually construct one other than Fuzzy Expert Systems and Fuzzy Reasoning, By William Siler and James J Buckley ISBN 0-471-38859-9 Copyright # 2005 John Wiley & Sons, Inc 1 2 INTRODUCTION for control, nor in the requirements that the emulation of though places on generalpurpose fuzzy reasoning systems Computer programming of rule-based fuzzy. .. are frequently encountered; fuzzy systems provide structured ways of handling uncertainties, ambiguities, and contradictions, none of which are ordinarily encountered in conventional computer programming Fuzzy systems also employ some special terms and concepts: fuzzy sets, fuzzy numbers, and membership functions Monotonic and nonmonotonic reasoning become routine concepts and acquire special meaning... differ from those for fuzzy reasoning? 1.8 What two kinds of people are usually involved in the construction of an expert system? 1.9 In what major respects do fuzzy expert systems differ from nonfuzzy systems? 1.10 What problems are encountered when first constructing a fuzzy expert system? 1.11 What important tool should be available for constructing a fuzzy expert system? 2 Rule-Based Systems: Overview... too restrictive for fuzzy reasoning; defuzzification and defuzzification are automatic and inescapable There are several development environments available for constructing fuzzy control systems A typical fuzzy control rule might be IF input1 is High AND input2 is Low THEN output is Zero Rules for fuzzy reasoning cannot be described so compactly The application domain of fuzzy control systems is well defined;... permit and the rules are enabled; the sequence in which the rules appear in the program has little or nothing to do with the order in which they are executed The systems are based on fuzzy systems theory, and include data types new to most programmers: fuzzy sets, fuzzy numbers, and truth values The use of discrete fuzzy sets permits convenient handling of ambiguities and contradictions All data and rules... rule-based reasoning such as the OPS family, Prolog, and CLIPS can be used For fuzzy expert systems, using familiar words as symbols to represent such concepts as fuzzy sets, fuzzy numbers, uncertainties, and modifying words (adjectives and adverbs) called hedges, special languages are available such as METUS (Cox, 1999); FLOPS, a fuzzy superset of OPS5, described in this book; and FRIL, a fuzzy superset... with the requisite fuzzy mathematics involved; Chapters 6 and 7 treat methods of fuzzy reasoning, that is, inferring new truths Chapter 8 deals with fuzzy expert system shells, the integrated development environments for constructing fuzzy expert systems Chapters 9 – 12 handle increasingly sophisticated problem-solving techniques Finally, Chapter 13 considers real-time on-line expert systems in which . Birmingham, Birmingham, AL 35294 JOHN WILEY & SONS, INC. FUZZY EXPERT SYSTEMS AND FUZZY REASONING FUZZY EXPERT SYSTEMS AND FUZZY REASONING William Siler Kemp-Carraway Heart Institute, Birmingham,. Characteristics of Expert Systems 2 1.1.1 Production Systems 3 1.1.2 Data-Driven Systems 4 1.1.3 Special Features of Fuzzy Systems 4 1.1.4 Expert Systems for Fuzzy Control and for Fuzzy Reasoning 5 1.2. Questions 54 4 Fuzzy Logic, Fuzzy Sets, and Fuzzy Numbers: II 57 4.1 Introduction 57 4.2 Algebra of Fuzzy Sets 57 4.2.1 T-Norms and t-Conorms: Fuzzy AND and OR Operators 57 4.2.2 Correlation Fuzzy Logic

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