one-third of the people with an age over twenty have some signs of degenerated discs. however, in most of the patients the mere presence of degenerative discs is not a problem leading to pain, neurological compression, or other symptoms. this paper presents an interval type-2 fuzzy hybrid rule-based system to diagnose the abnormal degenerated discs where pain variables are represented by interv...

We define the Cartesian product, composition, union and join on interval-valued fuzzy graphs and investigate some of their properties. We also introduce the notion of interval-valued fuzzy complete graphs and present some properties of self complementary and self weak complementary interval-valued fuzzy complete graphs.

There exists infinitely many ways to extend the classical propositional connectives to the set [0, 1] such that the behavior in its extremes is as in the classical logic. Still, it is a consensus that it is not sufficient, demanding that these extensions also preserve some minimal logical properties of the classical connectives. Thus, the notions of t-norms, t-conorms, fuzzy negations, and fuzz...

  The fuzzy approach has undergone a profound structural transformation in the past few decades. Numerous studies have been undertaken to explain fuzzy approach for linear and nonlinear programs. While, the findings in earlier studies have been conflicting, recent studies of competitive situations indicate that fractional programming problem has a positive impact on comparative scenario. We pro...

Let I = [a, b] be a real compact interval and f : I → I a continuous function. Define Kc([a, b]) the class of all non empty compact subinterval of [a, b] and let f̄ the natural extension of f to Kc([a, b]), that is to say, f̄(J) = f(J) for all J ∈ I([a, b]). Also, let Fc([a, b]) the class of all fuzzy-intervals with support contained in [a, b] and consider f̂ the Zadeh’s extension of f to Fc([a, b...

The multiobjective two person matrix game problem with fuzzy payoffs is considered in this paper. It is assumed that fuzzy payoffs are triangular fuzzy numbers. The problem is converted to several multiobjective matrix game problems with interval payoffs by using the $alpha$-cuts of fuzzy payoffs. By solving these problems some $alpha$-Pareto optimal strategies with some interval outcomes are o...

Abstract In this paper, our aim is to consider the new class of log-convex fuzzy-interval-valued function known as log- s -convex functions (log- fuzzy-IVFs). By concept, we have introduced Hermite–Hadamard inequalities (HH-inequalities) by means fuzzy order relation. This relation defined level-wise through Kulisch–Miranker on interval space. Moreover, some Hermite–Hadamard–Fejér (HH–Fejér-ine...

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. ...