Several new results in the field of aggre-gation operators are recalled. Most of them were or will be presented at 24 th Finally, a personal vision of the future development of the theory of aggregation operators is given.

Lipschitzian and kernel aggregation operators with respect to the natural T indistinguishability operator ET and their powers are studied. A t-norm T is proved to be ET -lipschitzian, and is interpreted as a fuzzy point and a fuzzy map as well. Given an archimedean t-norm T with additive generator t, the quasi-arithmetic mean generated by t is proved to be the more stable aggregation operator w...

based on Detyniecki's doctoral thesis [15]: "Mathematical aggregation operators and their application to video querying", directed by B. Bouchon-Meunier and R. Yager. The complete document is available as a LIP6 research report: 2001-002. Ask for a printed version of the thesis or download it from http://www.lip6.fr/reports/index-eng.html. I also would like to thank Radko Mesiar for all the com...

The paper deals with an extension of aggregation operators from the set of real numbers (or interval [0, 1]) to the set of fuzzy truth values (fuzzy sets in [0, 1]). We define so-called type-2 aggregation operator and show that an extension of ordinary aggregation operator by convolution is a type-2 aggregation operator. Finally we show that ordinary aggregation operator, as well as aggregation...

Stability of aggregation operators is characterized and discussed. 1-stability turns to coincide with 1-Lipschitz p r o p erty. Several examples and basic results are given.

An aggregation operator [1, 5, 7, 8, 9, 12] is usually defined as a real function An such that, from n data items x1, . . . ,xn in [0,1], produces an aggregated value An(x1, . . . ,xn) in [0,1] [4]. This definition can be extended to consider the whole family of operators for any n instead of a single operator for an specific n. This has led to the current standard definition [4, 15] of a famil...