In this paper, we define the notions of ultra and involution ideals in $BCK$-algebras. Then we get the relation among them and other ideals as (positive) implicative, associative, commutative and prime ideals. Specially, we show that in a bounded implicative $BCK$-algebra, any involution ideal is a positive implicative ideal and in a bounded positive implicative lower $BCK$-semilattice, the not...

The notion of positive implicative vague ideals in BCKalgebras is introduced. A relation between a vague ideal and a positive implicative vague ideal is discussed. Characterizations of a positive implicative vague ideal are considered. 2010 AMS Classification: 06F35, 03G25, 03E72

 In this paper, we aresupposed to introduce the definitions of n-fold commutative, andimplicative hyper K-ideals. These definitions are thegeneralizations of the definitions of commutative, andimplicative hyper K-ideals, respectively, which have been definedin [12]. Then we obtain some related results. In particular wedetermine the relationships between n-fold implicative hyperK-ideal and n-fol...

In this paper, we present the notions of cubic (weak) implicative hyper BCK-ideals of hyper BCKalgebras and then we present some results which characterize the above notions according to the level subsets. In addition, we obtain the relationship among these notions, cubic positive implicative hyper BCK-ideals of types-1, 2...8 and obtain some related results.AMS (2010): 06F35.

We consider the fuzzification of the notion of an n-fold positive implicative ideal. We give characterizations of an n-fold fuzzy positive implicative ideal. We establish the extension property for n-fold fuzzy positive implicative ideals, and state a characterization of PIn-Noetherian BCK-algebras. Finally we study the normalization of n-fold fuzzy positive implicative ideals. 2000 Mathematics...

Fuzzy (weak) implicative hyper K-ideals are introduced, and relations among fuzzy weak implicative hyper K-ideals, fuzzy implicative hyper K-ideals and fuzzy hyper K-ideals are discussed.

The notions of coupled N -subalgebra, coupled (positive implicative) N -ideals of d-algebras are introduced, and related properties are investigated. Characterizations of a coupled N -subalgebra and a coupled (positive implicative) N -ideals of d-algebras are given. Relations among a coupled N -subalgebra, a coupled N -ideal and a coupled positive implicative N -ideal of d-algebras are discussed.

in this paper we characterize hyper mv -algebras in which 0 or1 are scalar elements . we prove that any nite hyper mv -algebra that 0is a scaler element in it, is an mv -algebra. finally we characterize hypermv -algebras of order 2 and order 3.

In this note first we define a BCK‐algebra on the states of a deterministic finite automaton. Then we show that it is a BCK‐algebra with condition (S) and also it is a positive implicative BCK‐algebra. Then we find some quotient BCK‐algebras of it. After that we introduce a hyper BCK‐algebra on the set of all equivalence classes of an equivalence relation on the states of a deterministic finite...