A Comprehensive Study of Rough Sets and Rough Fuzzy Sets on Two Universes
نویسندگان
چکیده
In rough set theory, the lower and upper approximation operators can be constructed via a variety of approaches. Various generalizations of rough approximation operators have been made over the years. This paper presents a framework for the study of rough sets and rough fuzzy sets on two universes of discourse. By means of a binary relation between two universes of discourse, a class of revised rough sets and revised rough fuzzy sets based on two universes have been proposed. Some properties of the new model are revealed. We believe that this model will be more natural in the sense that rough sets (resp. rough fuzzy sets) are approximated by sets (resp. fuzzy sets) on the same universe. Moreover, some results, examples and counter examples are provided.
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