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This paper is a continuation of our previous work [10]. By GAERS-1, we denote the class of generalized abelian exchange rings with stable range 1. In this paper, we first prove that for any ring R ∈ GAERS-1 and any ideal I of R, K0(R/I) is an archimedean ℓ-group, which is a natural generalization of [10, Theorem 5.3]. As applications, we establish explicit characterizations for the K0-simplicity of such rings in the sense of [3], and investigate the norm completeness of their K0-groups. Finally, we characterize the primitive idempotents in R by K0(R) with ordered structure, from which we can further determine completely the structure of K0(R). [ABSTRACT FROM AUTHOR]

An ideal I of a ring R is strongly separative provided that for all finitely generated projective R-modules A, B with A=AI and B=BI, if 2A ≅ A ⊕ B, then A ≅ B. We prove in this paper that a regular ideal I of a ring R is strongly separative if and only if each a ∈ 1+I satisfying (1-a)R ∝ r(a) is unit-regular, if and only if each a ∈ 1+I satisfying (1-a2)R ∝ r(a2) is unit-regular, if and only if each a ∈ 1+I satisfying R(1-a)R=R r(a) is unit-regular, if and only if each a ∈ 1+I satisfying R(1-a2)R=R r(a2) is unit-regular. [ABSTRACT FROM AUTHOR]

In this paper we define prime, strongly prime and semiprime k-bi-ideals of a hemiring. We also define their fuzzy versions and characterize hemirings by the properties of these k-bi-ideals. [ABSTRACT FROM AUTHOR]

In this paper, we consider GC-projective, injective and flat modules and dimensions under change of rings. [ABSTRACT FROM AUTHOR]

The quasi-Baer condition of R/P(R) is investigated when R is a quasi-Baer ring, where P(R) is the prime radical of R. We provide an example of quasi-Baer ring R such that R/P(R) is not quasi-Baer. However, when P(R) is nilpotent, we prove that if R is a quasi-Baer (resp., Baer) ring, then R/P(R) is quasi-Baer (resp., Baer). Examples which illustrate and delimit the results of this paper are provided. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a pseudo-metric on the space of all m × s matrices with entries from the finite ring Zq, generalizing the classical Lee metric and the array RT metric, and name this pseudo-metric as the generalized Lee-RT pseudo-metric (or the GLRTP-metric). We also obtain some bounds on the parameters of array codes equipped with the GLRTP-metric. [ABSTRACT FROM AUTHOR]

It is well known that there are several non-equivalent types of prime near-rings which are all equivalent in the case of associative rings. In this paper we introduce various characterizations of prime modules in a zero-symmetric near-ring R. The connection of a prime R-ideal P of a module M and the ideal (P:M) of the near-ring R is also investigated. [ABSTRACT FROM AUTHOR]

Let R be a ring and α,β be endomorphisms of R. An additive mapping F: R → R is called a generalized (α,β)-derivation on R if there exists an (α,β)-derivation d: R → R such that F(xy)=F(x) α(y) + β(x)d(y) holds for all x, y ∈ R. In the present paper, we discuss the commutativity of a prime ring R admitting a generalized (α,β)-derivation F satisfying any one of the properties: (i) [F(x),x]α,β=0, (ii) F([x,y])=0, (iii) F(x ◦ y)=0, (iv) F([x,y])=[x,y]α,β, (v) F(x ◦ y)=(x ◦ y)α,β, (vi) F(xy)- α(xy) ∈ Z(R), (vii) F(x)F(y)- α(xy) ∈ Z(R) for all x, y in an appropriate subset of R. [ABSTRACT FROM AUTHOR]

Let (W,S) be a Weyl group of type Bn. In this paper, we find certain nontrivial distinguished involutions in the two-sided cell Ωt of W with a-value $\frac12(n^2-n+4t^2+2t)$ for 1≤ 2t ≤ n and n even (resp., $\frac12(n^2-n+4t^2-2t)$ for 1≤ 2t < n and n odd). Besides, for 1≤ i1< ⋯ < it≤ n-1, let Li1⋯ it be a left cell of W with a-value t2 and R(Li1⋯ it) ={si1,...,sit}. There are only two involutions y(i1,i1)⋯ y(it-1,it-1) sit and y(i1,i1)⋯ y(it,it) in the left cell Li1⋯ it. We prove that the former (resp., latter) is a distinguished involution in the left cell Li1⋯ it for t odd (resp., even). [ABSTRACT FROM AUTHOR]

In this paper, we define the notion of dimension filtration of an Artinian module and study a class of Artinian modules, called sequentially co-Cohen–Macaulay modules, which contains strictly all co-Cohen–Macaulay modules. Some characterizations of co-Cohen–Macaulayness in terms of the Matlis duality and of local homology are also given. [ABSTRACT FROM AUTHOR]

In this paper, δ-lifting and δ-supplemented modules are defined as generalizations of lifting and supplemented modules. Several properties of these modules are proved. New characterizations of δ-semiperect and δ-perfect rings studied in [9] are obtained using δ-lifting and δ-supplemented modules. [ABSTRACT FROM AUTHOR]

In the present paper, we extend some well-known results concerning derivations of prime rings to generalized derivations, [ABSTRACT FROM AUTHOR]

Let X and M be R-modules. We define the class B(M, X) = [A ≤ M ¦ ∃Y ≤ X, ∃ f ∈ Hom(M, X/Y), Ker f/A « M/A] and generalize (small-) projective modules in a recent paper by Keskin via the class B(M, X). We also characterize when the direct sum of two X-lifting modules is X-lifting via small projectivity and pseudo-projectivity of modules. As a corollary, we prove that if lifting modules M1 and M2 are relatively small projective and M1 is pseudo-M2-projective (or M2 is pseudo-M1-projective), then M = M1 ⊕ M2 is lifting. [ABSTRACT FROM AUTHOR]