Multi-granulation rough filters and rough fuzzy filters in Pseudo-BCI algebras

Abstract

This paper introduced the notions of rough filters, multi-granulation rough filters, and rough fuzzy filters in pseudo-BCI algebras and investigated some properties. First, a congruence relation was structured by a filter on pseudo-BCI algebra. Then rough filters and rough fuzzy filters were investigated. Next, the relationships between upper (lower) rough filters and upper (lower) approximations of their fuzzy homomorphic images were discussed. Furthermore, original rough filter model was extended to a multi-granulation rough filter model, where the set approximations were defined by using multi congruence relations on pseudo-BCI algebra.