A problem of reducing intuitionistic fuzzy matrices is examined and some useful properties are obtained with respect to nilpotent intutionistic fuzzy matrices. First, reduction of irreflexive and transitive intuitionistic fuzzy matrices are considered, and then the properties are applied to nilpotent intutionistic fuzzy matrices. Nilpotent intuitionistic fuzzy matrices are intuitionistic fuzzy ...

In this paper, we investigate duality of modular g-Riesz bases and g-Riesz bases in Hilbert C*-modules. First we give some characterization of g-Riesz bases in Hilbert C*-modules, by using properties of operator theory. Next, we characterize the duals of a given g-Riesz basis in Hilbert C*-module. In addition, we obtain sufficient and necessary condition for a dual of a g-Riesz basis to be agai...

Feature structures are informational elements that have been used in several linguistic theories and in computational systems for natural-language processing. A logicaJ calculus has been developed and used as a description language for feature structures. In the present work, a framework in three-valued logic is suggested for defining the semantics of a feature structure description language, a...

The concept of quasi-coincidence of an interval-valued fuzzy set is considered. By using this new idea, the notion of interval-valued (α, β)−fuzzy k−ideals of semirings is introduced, which is a generalization of a fuzzy k−ideal. Also some related properties are studied and in particular, the interval-valued (∈,∈ ∨q)−fuzzy k−ideals in a semiring will be investigated. Finally, the concept of imp...

On a structuralist account of logic, the logical operators, as well as modal operators are defined by the specific ways that they interact with respect to implication. As a consequence, the same logical operator (conjunction, negation etc.) can appear to be very different with a variation in the implication relation of a structure. We illustrate this idea by showing that certain operators that ...

In this paper we present a method for the construction of Atanassov’s intuitionistic fuzzy S-implications that satisfy the following property: if in the intuitionistic fuzzy conditional the antecedent is equal to the consequent, then the Atanassov’s intuitionistic fuzzy implication operator has the same Atanassov’s intuitionistic fuzzy index as the antecedent and the consequent.

We find some exact solutions of the Knizhnik-Zamolodchikov equation for the four point correlation functions that occur in the SL(2, R) WZNW model. They exhibit logarithmic behaviour in both the Kac-Moody and Virasoro parts. We discuss their implication for the operator product expansion. We also observe the appearance of several symmetries of the correlation functions. [email protected]...

We introduce the notion of Krein-operator convexity in the setting of Krein spaces. We present an indefinite version of the Jensen operator inequality on Krein spaces by showing that if (H , J) is a Krein space, U is an open set which is symmetric with respect to the real axis such that U ∩ R consists of a segment of real axis and f is a Kreinoperator convex function on U with f(0) = 0, then f(...

Every time we detect a part that is out of tolerance, the implication is that something went wrong in the machining process: either the operator made a mistake, or the machine tool did. A lot of the time, problems with the machine get blamed on the operator. Rather than expect the operator to compensate for every machine tool problem -at the expense of increased setup time and scrap -it makes m...

We give examples of composition operators CΦ on H(D) showing that the condition ‖Φ‖∞ = 1 is not sufficient for their approximation numbers an(CΦ) to satisfy limn→∞[an(CΦ)] √ n = 1, contrary to the 1-dimensional case. We also give a situation where this implication holds. We make a link with the Monge-Ampère capacity of the image of Φ. Key-words : approximation numbers; Bergman space; bidisk; co...