Abstract :
In this paper, for any two elements y; u of a BCK-algebra X,
we assign a subset of X, denoted by Sy(u), and investigate some related
properties. We show that Sy(u) is a subalgebra of X for all y; u 2 X.
Using these subalgebras, we characterize the involutive BCK-algebras,
and give a necessary and suffcient condition for a bounded BCK-algebra
to be a commutative BCK-chain. Finally, we show that the set of all
subalgebras Sy(u) forms a bounded distributive lattice.
Keywords :
bounded distributive lattice , im- plicative BCK-algebra , commutative BCK-chain , BCK-algebra