The main goal of this contribution is to introduce the concept of higher order hesitant fuzzy soft set as an extension of fuzzy soft set that encompasses most of the existing extensions of fuzzy soft set as special cases. Furthermore, this new concept provides us with a method for dealing with multicriteria fuzzy decision making problems which are difficult to explain in other existing extensio...

Research on soft set based decision making has received much attention in recent years. Feng et al. presented an adjustable approach to fuzzy soft sets based decision making by using level soft set, and subsequently extended the approach to interval-valued fuzzy soft set based decision making. Jiang et al. generalize the approach to solve intuitionistic fuzzy soft sets based decision making. In...

Molodtsov introduced the theory of soft sets, which can be used as a general mathematical tool for dealing with uncertainty. This paper aims to introduce the concept of the type-2 fuzzy soft set by integrating the type-2 fuzzy set theory and the soft set theory. Some operations on the type-2 fuzzy soft sets are given. Furthermore, we investigate the decision making based on type-2 fuzzy soft se...

In this work, we define a fuzzy soft set theory and its related properties. We then define fuzzy soft aggregation operator that allows constructing more efficient decision making method. Finally, we give an example which shows that the method can be successfully applied to many problems that contain uncertainties.

In this paper we introduce k(1,2) and k(2,1) near subtraction semigroup, prove some of their elementary properties and show that under certain conditions these two concepts are equivalent. Mathematics Subject Classification: 06F35

In this paper, we introduce the concept of intuitionistic fuzzy ideals of subtraction algebras. We obtain the characterizations of intuitionistic fuzzy ideals in subtraction algebras. Using a collection of ideals with additional conditions, we construct an intuitionistic fuzzy ideal and we obtain some related properties of it. Mathematics Subject Classification: 03G25, 04A72, 08A72