TY - JOUR
ID - 6482
TI - Quasi-projective covers of right $S$-acts
JO - Categories and General Algebraic Structures with Applications
JA - CGASA
LA - en
SN - 2345-5853
AU - Roueentan, Mohammad
AU - Ershad, Majid
AD - Department of Mathematics, College of
Science, Shiraz University, Shiraz 71454, Iran.
AD - Department of Mathematics, College of Science, Shiraz University, Shiraz 71454, Iran.
Y1 - 2014
PY - 2014
VL - 2
IS - 1
SP - 37
EP - 45
KW - Projective
KW - quasi-projective
KW - perfect
KW - semiperfect
KW - cover
DO -
N2 - In this paper $S$ is a monoid with a left zero and $A_S$ (or $A$) is a unitary right $S$-act. It is shown that a monoid $S$ is right perfect (semiperfect) if and only if every (finitely generated) strongly flat right $S$-act is quasi-projective. Also it is shown that if every right $S$-act has a unique zero element, then the existence of a quasi-projective cover for each right act implies that every right act has a projective cover.
UR - http://cgasa.sbu.ac.ir/article_6482.html
L1 - http://cgasa.sbu.ac.ir/article_6482_f25fef016a297f3166ecafec83d649d8.pdf
ER -