Topological structure of covering rough sets
نویسندگان
چکیده
In this study, we induce some topological structures in the covering rough set models, and construct their closure operators by using the covering upper approximation operators. Furthermore, we show that the minimum set of each of these topological structures is their base, and a partition on the universe of discourse. Finally, we discuss the relationships between some topologies generated by some approximation operators and unary covering. 2010 AMS Classification: 54H99, 68T37
منابع مشابه
Structure of Covering-based Rough Sets
Rough set theory is a very effective tool to deal with granularity and vagueness in information systems. Covering-based rough set theory is an extension of classical rough set theory. In this paper, firstly we present the characteristics of the reducible element and the minimal description covering-based rough sets through downsets. Then we establish lattices and topological spaces in coveringb...
متن کاملOn topological covering-based rough spaces
Rough set theory, a mathematical tool to deal with vague concepts, has originally described the indiscernibility of elements by equivalence relations. Covering-based rough sets are a natural extension of classical rough sets by relaxing the partitions arising from equivalence relations to coverings. Recently, some topological concepts such as subbase, neighborhood and separation axioms have bee...
متن کاملMultigranulation single valued neutrosophic covering-based rough sets and their applications to multi-criteria group decision making
In this paper, three types of (philosophical, optimistic and pessimistic) multigranulation single valued neutrosophic (SVN) covering-based rough set models are presented, and these three models are applied to the problem of multi-criteria group decision making (MCGDM).Firstly, a type of SVN covering-based rough set model is proposed.Based on this rough set model, three types of mult...
متن کاملTOPOLOGICAL SIMILARITY OF L-RELATIONS
$L$-fuzzy rough sets are extensions of the classical rough sets by relaxing theequivalence relations to $L$-relations. The topological structures induced by$L$-fuzzy rough sets have opened up the way for applications of topological factsand methods in granular computing. In this paper, we firstly prove thateach arbitrary $L$-relation can generate an Alexandrov $L$-topology.Based on this fact, w...
متن کاملCovering Numbers in Covering-Based Rough Sets
Rough set theory provides a systematic way for rule extraction, attribute reduction and knowledge classification in information systems. Some measurements are important in rough sets. For example, information entropy, knowledge dependency are useful in attribute reduction algorithms. This paper proposes the concepts of the lower and upper covering numbers to establish measurements in covering-b...
متن کاملCovering Rough Sets From a Topological Point of View
—Covering-based rough set theory is an extension to classical rough set. The main purpose of this paper is to study covering rough sets from a topological point of view. The relationship among upper approximations based on topological spaces are explored.
متن کامل