A ring is called n-Perfect (n≥ 0) if every flat module has projective dimension less or equal
than n. In this paper we introduce “Strong n-Perfect rings” which is in some way a …

A ring is called $ n $-perfect ($ n\geq 0$), if every flat module has projective dimension less
or equal than $ n $. In this paper, we show that the $ n $-perfectness relate, via homological …

Let R be a ring and n, k be two non-negative integers. As an extension of several known
notions, we introduce and study (n, k)-weak cotorsion modules using the class of right R …

We introduce the concepts of (n, d)-injective and (n, d)-flat as generalizations of injective, flat
modules and homological dimensions, and use them to characterize right n-coherent rings …

Let R be a ring and na fixed non-negative integer. In this paper, n-weak cotorsion modules
are introduced and studied. A right R-module N is called n-weak cotorsion module if Ext …

Let R be a ring, na fixed non-negative integer and ℱ ℐ n (ℱ n) the class of all right (left) R-
modules of FP-injective (flat) dimension at most n. We prove that (is a perfect cotorsion …

R is called a right ${\Pi}-coherent $ ring in case every finitely generated torsion less right R-
module is finitely presented. In this paper, we define a dimension for rings, called ${\Pi} …

Following, a ring R is called right almost-perfect if every flat right R-module is projective
relative to R. In this article, we continue the study of these rings and will find some new …

This paper introduces and studies homological properties of new classes of modules,
namely, the $\mathcal F_1 $-flat modules and the $\mathcal F_1^{\fp} $-flat modules, where …

Several authors have been interested in cotorsion theories. Among these theories we figure
the pairs $(\mathcal P_n,\mathcal P_n^{\perp}) $, where $\mathcal P_n $ designates the set …