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The lower and upper approximations in a hypergroup. (English) Zbl 1156.68585
Summary: This paper presents a relationship between rough sets and hypergroup theory. We analyze the lower and upper approximations of a subset, with respect to an invertible subhypergroup and we consider some particular situations. Moreover, the notion of a rough subhypergroup is introduced. Finally, fuzzy rough subhypergroups are introduced and characterized.
MSC:
68T30Knowledge representation
68T37Reasoning under uncertainty
20N20Hypergroups (group theory)
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