Soju structures with applications in BCK/BCI-algebras

Abstract

A new structure, so called soju structure, is introduced by combining intuitionistic fuzzy set and soft set, which is applied to BCK/BCI-algebras. The notions of soju subalgebra and soju ideal in BCK/BCI-algebras are introduced, and related properties are investigated. A strong soju subalgebra in BCI-algebras is introduced, and a condition for a soju subalgebra to be strong is provided. Relations between soju subalgebra and soju ideal are discussed, and conditions for a soju structure to be a soju ideal in a BCK-algebra are considered. Characterizations of soju subalgebra and soju ideal are considered, and the homomorphic image and preimage of soju subalgebra is discussed.