Topological Structures of Rough Sets Induced by Equivalence Relations
Michiro Kondo* and Wieslaw A. Dudek**
*School of Information Environment, Tokyo Denki University, Inzai 270-1382, Japan
**Institute of Mathematics, Wroclaw University of Technology, Wroclaw 50-370, Poland
In this paper we consider some fundamental topological properties of rough sets induced by equivalence relations and show that 1. Every approximation space is retrieval. 2. For every approximation space X=(X,θ), X is strongly connected if and only if θ=X×X. Moreover we consider topological properties of generalized rough sets.
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