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This comprehensive and accurate survey of state-of-art research on intuitionistic fuzzy sets theory updates the author´s work over the past 12 years, and describes the latest general ideas and open problems in this expanding field.

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This book aims to be a comprehensive and accurate survey of state-of-art research on intuitionistic fuzzy sets theory and could be considered a continuation and extension of the author s previous book on Intuitionistic Fuzzy Sets, published by Springer in 1999 (Atanassov, Krassimir T., Intuitionistic Fuzzy Sets, Studies in Fuzziness and soft computing, ISBN 978-3-7908-1228-2, 1999). Since the aforementioned book has appeared, the research activity of the author within the area of intuitionistic fuzzy sets has been expanding into many directions. The results of the author s most recent work covering the past 12 years as well as the newest general ideas and open problems in this field have been therefore collected in this new book.

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On the concept of IFSs.- Operations and relations over IFSs.- Geometrical interpretations of IFSs.- Modal and topological operators.- Extended modal operators.- Other types of operators.- Norms and metrics over IFSs.- Intuitionistic Fuzzy Relations (IFRs).- New intuitionistic fuzzy operations.- On two new extensions of intuitionistic fuzzy sets.- Concluding remarks.

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From the reviews:

"The volume is a comprehensive, carefully organized, in-depth treatise on intuitionistic fuzzy sets ... . The material structured into 11 chapters is split into several main parts. The concepts of intuitionistic fuzzy sets (IFS) are motivated through a series of illustrative examples including those showing their geometric interpretations. ... The exposure of the formal material is good with well thought-out arguments and a wealth of illustrative material. Overall, the book provides a very good reading for those interested in IFS." (Witold Pedrycz, Zentralblatt MATH, Vol. 1247, 2012)

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