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Relational interpretations of neighborhood operators and rough set approximation operators. (English) Zbl 0949.68144
The author presents a generalization of the rough set approach by introducing neighborhood systems defined by binary relations. For each object of the universe of such a system a nonempty family of subsets of the universe is associated. Some relationships with modal logic are summarized. The neighborhood systems are then used to define and study the basic properties of set approximations.
MSC:
68T37Reasoning under uncertainty
03E72Fuzzy set theory
68T27Logic in artificial intelligence