We study multigranulation spaces of two equivalences. The lattice-theoretical properties of so-called "optimistic" and "pessimistic" multigranular approximation systems are given. We also consider the ordered sets of rough sets determined by these approximation pairs.

中文翻译：

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多粒粗糙集的结构

我们研究两个等价的多粒度空间。给出了所谓的“乐观”和“悲观”多粒度近似系统的晶格理论特性。我们还考虑由这些近似对确定的粗糙集的有序集。