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http://dx.doi.org/10.5831/HMJ.2019.41.4.799

RINGS WITH VARIATIONS OF FLAT COVERS  

Demirci, Yilmaz Mehmet (Department of Engineering Science, Abdullah Gul University)
Turkmen, Ergul (Department of Mathematics, Amasya University)
Publication Information
Honam Mathematical Journal / v.41, no.4, 2019 , pp. 799-812 More about this Journal
Abstract
We introduce flat e-covers of modules and define e-perfect rings as a generalization of perfect rings. We prove that a ring is right perfect if and only if it is semilocal and right e-perfect which generalizes a result due to N. Ding and J. Chen. Moreover, in the light of the fact that a ring R is right perfect if and only if flat covers of any R-module are projective covers, we study on the rings over which flat covers of modules are (generalized) locally projective covers, and obtain some characterizations of (semi) perfect, A-perfect and B-perfect rings.
Keywords
flat e-cover; e-perfect ring; flat-locally projective cover; perfect ring;
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