Some new types of closure operators that are generalization of a Kuratowski operator are defined throughout this paper. From these operators, we give new models of upper approximations, lower approximations and boundary regions that are basic notions in rough set theory. So, we investigate new concepts of rough sets, exact sets and some of their properties are studied. New forms of topological structures in terms of closure operators are established.
2020 Mathematics Subject Classification: 03E47, 03E75, 37B10, 54A05, 54A10, 97E60.