Intuitionistic fuzzy rough sets model based on (Θ, Φ)-operators

The extension of rough set model is an important research direction in rough set theory. The aim of this paper is to present a new extension. At the first, we introduce a pair of dual intuitionistic fuzzy operators (Θ, Φ). And some important properties are examined about these these operators. Moreover, θ-lower and φ-upper approximation operators are defined, by using the operators, and a novel intuitionistic fuzzy rough set model is constructed based on an intuitionistic fuzzy equivalence relation. Furthermore, some valuable properties are obtained in the model.