On Some Topological Properties of Pessimistic Multigranular Rough Sets
نویسندگان
چکیده
منابع مشابه
On Some Topological Properties of Pessimistic Multigranular Rough Sets
Rough set theory was introduced by Pawlak as a model to capture impreciseness in data and since then it has been established to be a very efficient tool for this purpose. The definition of basic rough sets depends upon a single equivalence relation defined on the universe or several equivalence relations taken one each at a time. There have been several extensions to the basic rough sets introd...
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Rough sets, introduced by Pawlak as a model to capture impreciseness in data have been a very useful tool in several applications. These basic rough sets are defined by taking equivalence relations over a universe. In order to enhance the modeling powers of rough sets, several extensions to the basic definition has been introduced over the past few years. Extending the single granular structure...
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Covering based rough sets [3,15,16,17,18,19] have been introduced as an extension of the basic rough sets introduced by Pawlak [6]. There is only one way to define the lower approximation of a set using covering. However, as many as four definitions have been proposed for the upper approximation. Accordingly, four types of covering based rough sets have been defined. In this paper we introduced...
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ژورنال
عنوان ژورنال: International Journal of Intelligent Systems and Applications
سال: 2012
ISSN: 2074-904X,2074-9058
DOI: 10.5815/ijisa.2012.08.02