on generalizations of semiperfect and perfect rings
نویسندگان
چکیده
we call a ring $r$ right generalized semiperfect if every simple right $r$-module is an epimorphic image of a flat right $r$-module with small kernel, that is, every simple right $r$-module has a flat $b$-cover. we give some properties of such rings along with examples. we introduce flat strong covers as flat covers which are also flat $b$-covers and give characterizations of $a$-perfect, $b$-perfect and perfect rings in terms of flat strong covers.
منابع مشابه
On generalizations of semiperfect and perfect rings
We call a ring $R$ right generalized semiperfect if every simple right $R$-module is an epimorphic image of a flat right $R$-module with small kernel, that is, every simple right $R$-module has a flat $B$-cover. We give some properties of such rings along with examples. We introduce flat strong covers as flat covers which are also flat $B$-covers and give characterizations of $A$-perfe...
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عنوان ژورنال:
bulletin of the iranian mathematical societyجلد ۴۲، شماره ۶، صفحات ۱۴۴۱-۱۴۵۰
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