AL-Rafidain Journal of Computer Sciences and Mathematics

Abstract

The concept of  q-semi-open sets in topological spaces was introduced in 1984 and 1986 by T. Noiri [9, 10]. In this paper we introduce and study a generalization of a contra pre semi-open maps due to (Caldas and Baker) [3], it is called contra pre qs-open maps, the maps whose images of a q-semi-open sets is q-semi-closed. Also, we introduce and study a new type of closed maps called contra pre qs-closed maps, which is stronger than contra pre semi-closed due to Caldas [2], the maps whose image of a q-semi-closed sets is q-semi-open.1991 Math. Subject Classification: 54 C10, 54 D 10.