Abebaw Tilahun (PhD)Hunegnaw Dejene2018-07-122023-11-042018-07-122023-11-042017-09http://etd.aau.edu.et/handle/123456789/8345In this project we consider the structure of semi groups of self mapping of a semi group S under pointwise composition, generated by the endomorphisms of S. It is shown that,ifS is Clifford semi groups with underlying semilattice ∧, the endomorphisms of S generate a Clifford semigroup E+ (S) whose underlying semilattice is the set of endomorphisms of ∧.These results contribute to the wider theory of seminear-rings of endomorphisms, Since E+ (S) has a natural structure as distributively generated seminear-ring.en“Clifford semigroupsThesis