title: Hesitant fuzzy soft subalgebras and ideals in BCK/BCI-algebras.
abstract: As a link between classical soft sets and hesitant fuzzy sets, the notion of hesitant fuzzy soft sets is introduced and applied to a decision making problem in the papers by Babitha and John (2013) and Wang et al. (2014). The aim of this paper is to apply hesitant fuzzy soft set for dealing with several kinds of theories in BCK/BCI-algebras. The notions of hesitant fuzzy soft subalgebras and (closed) hesitant fuzzy soft ideals are introduced, and related properties are investigated. Relations between a hesitant fuzzy soft subalgebra and a (closed) hesitant fuzzy soft ideal are discussed. Conditions for a hesitant fuzzy soft set to be a hesitant fuzzy soft subalgebra are given, and conditions for a hesitant fuzzy soft subalgebra to be a hesitant fuzzy soft ideal are provided. Characterizations of a (closed) hesitant fuzzy soft ideal are considered.
authors.affiliation: Department of Mathematics Education, Gyeongsang National University, Jinju 660-701, Republic of Korea.
authors.forename: Young Bae
authors.initials: YB
authors.lastname: Jun
authors.affiliation: Department of Mathematics Education, Dongguk University, Seoul 100-715, Republic of Korea.
authors.forename: Sun Shin
authors.initials: SS
authors.lastname: Ahn
authors.affiliation: Department of Mathematics, University of Tabuk, Tabuk 71491, Saudi Arabia.
authors.forename: G
authors.identifier: 0000-0002-5596-5841
authors.initials: G
authors.lastname: Muhiuddin
mesh_terms: D000465:Algorithms; D003657:Decision Making; D017143:Fuzzy Logic; D015233:Models, Statistical; D035501:Uncertainty