In many real world applications, information blocks form a covering of a universe. Covering-based rough set theory has been proposed to deal with this type of information. It is more general and complex than classical rough set theory, hence there is much need to develop sophisticated structures to characterize covering-based rough sets. Matroids are important tools for describing graphs and li...

Covering is a widely used form of data structures. Covering-based rough set theory provides a systematic approach to this data. In this paper, graphs are connected with covering-based rough sets. Specifically, we convert some important concepts in graph theory including vertex covers, independent sets, edge covers, and matchings to ones in covering-based rough sets. At the same time, correspond...

Covering-based rough set theory is a useful tool to deal with inexact, uncertain or vague knowledge in information systems. Geometric lattice has widely used in diverse fields, especially search algorithm design which plays important role in covering reductions. In this paper, we construct four geometric lattice structures of covering-based rough sets through matroids, and compare their relatio...

Covering rough set theory provides an effective approach to dealing with uncertainty in data analysis. Knowledge acquisition is a main issue in covering rough set theory. However, the original rough set methods are still expensive for this issue in terms of time consumption. To further improvement, we propose fast approaches to knowledge acquisition in covering information systems by employing ...

Covering is a common type of data structure and covering-based rough set theory is an efficient tool to process this data. Lattice is an important algebraic structure and used extensively in investigating some types of generalized rough sets. In this paper, we propose two family of sets and study the conditions that these two sets become some lattice structures. These two sets are consisted by ...

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...