Rough prime ideals and rough fuzzy prime ideals in semigroups

In this paper, we shall introduce the notions of rough prime ideals and rough fuzzy prime ideals in a semigroup, and give some properties of such ideals. Also, we will discuss the relations between the upper [lower] rough prime ideals and the upper [lower] approximations of their homomorphism images. (C) 2005 Elsevier Inc. All rights reserved.