Li and Yu (Fuzzy Sets and Systems 101 (1999) 109) argued that the model of Yang et al. for fuzzy programming (Fuzzy Sets and Systems 41 (1991) 39) is correct only for a speci2c type of piecewise linear membership function and proposed their model for other type of membership functions. This study generalizes the model of Yang et al. A numerical example indicates that the model of Li and Yu is i...

When 60 years ago Shannon established “A Mathematical Theory of Communication” nobody could know the consequences for science and technology in the second half of the century. Shannon published his article in two parts in the July and October 1948 editions of the Bell System Technical Journal. However, it is very probable that this article wouldn’t have become famous without the help of Weaver,...

Carlsson and Fuller [C. Carlsson, R. Fuller, On possibilistic mean value and variance of fuzzy numbers, Fuzzy Sets and Systems 122 (2001) 315–326] have introduced possibilisticmean, variance and covariance of fuzzy numbers and Fuller andMajlender [R. Fuller, P. Majlender, On weighted possibilistic mean and variance of fuzzy numbers, Fuzzy Sets and Systems 136 (2003) 363–374] have introduced the...

Fuzzy relations are able to model vagueness, in the sense that they provide the degree to which two objects are related to each other. However, they cannot model uncertainty: there is no means to attribute reliability information to the membership degrees. Intuitionistic fuzzy sets, as de1ned by Atanassov (Instuitionistic Fuzzy Sets, Physica-Verlag, Heidelberg, New York, 1999), give us a way to...

Let ďc be computable reducibility on ceers. We show that for every computably enumerable equivalence relation (or ceer) R with infinitely many equivalence classes, the index sets ti : Ri ďc Ru (with R non-universal), ti : Ri ěc Ru, and ti : Ri ”c Ru are Σ3 complete, whereas in case R has only finitely many equivalence classes, we have that ti : Ri ďc Ru is Π2 complete, and ti : Ri ěc Ru (with R...

Kim and Bishu (Fuzzy Sets and Systems 100 (1998) 343-352) proposed a modification of fuzzy linear regression analysis. Their modification is based on a criterion of minimizing the difference of the fuzzy membership values between the observed and estimated fuzzy numbers. We show that their method often does not find acceptable fuzzy linear regression coefficients and to overcome this shortcomin...

Fuzziness is not a priori an obvious concept and demands some explanation. “Fuzziness” is what Black (NF 1937) calls “vagueness” when he distinguishes it from “generality” and from “ambiguity.” Generalizing refers to the application of a symbol to a multiplicity of objects in the field of reference, ambiguity to the association of a finite number of alternative meanings having the same phonetic...

Atanassov K. , Intuitionistic Fuzzy Sets. , VII ITKR's Section, Sofia, June 1983. Hashimoto H. , Sub-inverses of fuzzy Matrices, Fuzzy Sets and Systems, Vol. 12(1984),155-168. Murugadas P and Lalitha K. , Dual Implication Operator in Intuitionistic Fuzzy Matrices, International conference on Mathematical Modelling and its Application-2012. Sriram S and Murugadas P. , Sub-inverses of Intuit...

Some simple yet pragmatic methods of consistency test are developed to check whether an interval fuzzy preference relation is consistent. Based on the definition of additive consistent fuzzy preference relations proposed by Tanino [Fuzzy Sets and Systems 12 (1984) 117131], a study is carried out to examine the correspondence between the element and weight vector of a fuzzy preference relation. ...

Ulrich Höhle was born on 6 December 1943 in Bad Oeynhausen, Germany. Being musically and mathematically gifted (among others), he could not decide between music and mathematics, so he began his studies in both directions: mathematics and music (piano) at Johannes-Gutenberg Universität in Mainz (1963–1966). After having realized his true vocation, he decided to become a mathematician and continu...