If we mark xy = 0 as x y in it, a BCI-algebra would be a partial ordering
set. But this relevance is not a one to one correspondence. It's clearly that a
partial ordering set could correspond to several BCI-algebras generally.
As that there would be some minimal elements in a partial ordering set, in
BCI-algebras there must be atoms.
Denition 1.2 [1]Supposing < X; ; 0 > is a BCI-algebra, while 2 X.
would be called as an atom of X while x a = 0 ) x = a. The set of all the
atoms of X is marked as L(X).
It's clearly that the atoms of a BCI-algebra are exactly the minimal ele-
ments in X as a partial ordering set.
And depends on the conception of atoms, the denition of branches has
been found as follows.
Denition 1.3 [1]Supposing < X; ; 0 > is a BCI-algebra, while is an atom
of X. The set fx 2 Xj x = 0g is named as a branch of X, marked as l.