• Title/Summary/Keyword: ${\phi}$-flat modules

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ON Φ-FLAT MODULES AND Φ-PRÜFER RINGS

  • Zhao, Wei
    • Journal of the Korean Mathematical Society
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    • v.55 no.5
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    • pp.1221-1233
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    • 2018
  • Let R be a commutative ring with non-zero identity and let NN(R) = {I | I is a nonnil ideal of R}. Let M be an R-module and let ${\phi}-tor(M)=\{x{\in}M{\mid}Ix=0\text{ for some }I{\in}NN(R)\}$. If ${\phi}or(M)=M$, then M is called a ${\phi}$-torsion module. An R-module M is said to be ${\phi}$-flat, if $0{\rightarrow}{A{\otimes}_R}\;{M{\rightarrow}B{\otimes}_R}\;{M{\rightarrow}C{\otimes}_R}\;M{\rightarrow}0$ is an exact R-sequence, for any exact sequence of R-modules $0{\rightarrow}A{\rightarrow}B{\rightarrow}C{\rightarrow}0$, where C is ${\phi}$-torsion. In this paper, the concepts of NRD-submodules and NP-submodules are introduced, and the ${\phi}$-flat modules over a ${\phi}-Pr{\ddot{u}}fer$ ring are investigated.

ON 𝜙-w-FLAT MODULES AND THEIR HOMOLOGICAL DIMENSIONS

  • Zhang, Xiaolei;Zhao, Wei
    • Bulletin of the Korean Mathematical Society
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    • v.58 no.4
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    • pp.1039-1052
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    • 2021
  • In this paper, we introduce and study the class of 𝜙-w-flat modules which are generalizations of both 𝜙-flat modules and w-flat modules. The 𝜙-w-weak global dimension 𝜙-w-w.gl.dim(R) of a commutative ring R is also introduced and studied. We show that, for a 𝜙-ring R, 𝜙-w-w.gl.dim(R) = 0 if and only if w-dim(R) = 0 if and only if R is a 𝜙-von Neumann ring. It is also proved that, for a strongly 𝜙-ring R, 𝜙-w-w.gl.dim(R) ≤ 1 if and only if each nonnil ideal of R is 𝜙-w-flat, if and only if R is a 𝜙-PvMR, if and only if R is a PvMR.

ON φ-VON NEUMANN REGULAR RINGS

  • Zhao, Wei;Wang, Fanggui;Tang, Gaohua
    • Journal of the Korean Mathematical Society
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    • v.50 no.1
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    • pp.219-229
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    • 2013
  • Let R be a commutative ring with $1{\neq}0$ and let $\mathcal{H}$ = {R|R is a commutative ring and Nil(R) is a divided prime ideal}. If $R{\in}\mathcal{H}$, then R is called a ${\phi}$-ring. In this paper, we introduce the concepts of ${\phi}$-torsion modules, ${\phi}$-flat modules, and ${\phi}$-von Neumann regular rings.

ON ϕ-(n, d) RINGS AND ϕ-n-COHERENT RINGS

  • Younes El Haddaoui;Hwankoo Kim;Najib Mahdou
    • Communications of the Korean Mathematical Society
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    • v.39 no.3
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    • pp.623-642
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    • 2024
  • This paper introduces and studies a generalization of (n, d)-rings introduced and studied by Costa in 1994 to rings with prime nilradical. Among other things, we establish that the ϕ-von Neumann regular rings are exactly either ϕ-(0, 0) or ϕ-(1, 0) rings and that the ϕ-Prüfer rings which are strongly ϕ-rings are the ϕ-(1, 1) rings. We then introduce a new class of rings generalizing the class of n-coherent rings to characterize the nonnil-coherent rings introduced and studied by Bacem and Benhissi.

ON 𝜙-SEMIPRIME SUBMODULES

  • Ebrahimpour, Mahdieh;Mirzaee, Fatemeh
    • Journal of the Korean Mathematical Society
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    • v.54 no.4
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    • pp.1099-1108
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    • 2017
  • Let R be a commutative ring with non-zero identity and M be a unitary R-module. Let S(M) be the set of all submodules of M and ${\phi}:S(M){\rightarrow}S(M){\cup}\{{\emptyset}\}$ be a function. We say that a proper submodule P of M is a ${\phi}$-semiprime submodule if $r{\in}R$ and $x{\in}M$ with $r^2x{\in}P{\setminus}{\phi}(P)$ implies that $rx{\in}P$. In this paper, we investigate some properties of this class of sub-modules. Also, some characterizations of ${\phi}$-semiprime submodules are given.