Abstract : Let $R$ be a commutative ring with identity. If the nilpotent radical $Nil(R)$ of $R$ is a divided prime ideal, then $R$ is called a $\phi$-ring. Let $R$ be a $\phi$-ring and $S$ be a multiplicative subset of $R$. In this paper, we introduce and study the class of nonnil-$S$-coherent rings, i.e., the rings in which all finitely generated nonnil ideals are $S$-finitely presented. Also, we define the concept of $\phi$-$S$-coherent rings. Among other results, we investigate the $S$-version of Chase's result and Chase Theorem characterization of nonnil-coherent rings. We next study the possible transfer of the nonnil-$S$-coherent ring property in the amalgamated algebra along an ideal and the trivial ring extension.
Abstract : Let $(M^{2m},\varphi,g)$ be a $B$-manifold. In this paper, we introduce a new class of metric on $(M^{2m},\varphi,g)$, obtained by a non-conformal deformation of the metric $g$, called a generalized Berger-type deformed metric. First we investigate the Levi-Civita connection of this metric. Secondly we characterize the Riemannian curvature, the sectional curvature and the scalar curvature. Finally, we study the proper biharmonicity of the identity map and of a curve on $M$ with respect to a generalized Berger-type deformed metric.
Abstract : Recently, Bre\v{s}ar's Jordan $\{g,h\}$-derivations have been investigated on triangular algebras. As a first aim of this paper, we extend this study to an interesting general context. Namely, we introduce the notion of Jordan $\mathcal{G}_n$-derivations, with $n \ge 2$, which is a natural generalization of Jordan $\{g,h\}$-derivations. Then, we study this notion on path algebras. We prove that, when $n > 2$, every Jordan $\mathcal{G}_n$-derivation on a path algebra is a $\{g,h\}$-derivation. However, when $n = 2$, we give an example showing that this implication does not hold true in general. So, we characterize when it holds. As a second aim, we give a positive answer to a variant of Lvov-Kaplansky conjecture on path algebras. Namely, we show that the set of values of a multi-linear polynomial on a path algebra $KE$ is either $\{0\}$, $KE$ or the space spanned by paths of a length greater than or equal to $1$.
Abstract : This paper is concerned with the study of spacetimes satisfying $\mathrm{div}\mathcal{M}=0$, where ``div" denotes the divergence and $\mathcal{M}$ is the $m$-projective curvature tensor. We establish that a perfect fluid spacetime with $\mathrm{div}\mathcal{M}=0$ is a generalized Robertson-Walker spacetime and vorticity free; whereas a four-dimensional perfect fluid spacetime becomes a Robertson-Walker spacetime. Moreover, we establish that a Ricci recurrent spacetime with $\mathrm{div}\mathcal{M}=0$ represents a generalized Robertson-Walker spacetime.
Abstract : The present article contains the study of $D$-homothetically deformed $f$-Kenmotsu manifolds. Some fundamental results on the deformed spaces have been deduced. Some basic properties of the Riemannian metric as an inner product on both the original and deformed spaces have been established. Finally, applying the obtained results, soliton functions, Ricci curvatures and scalar curvatures of almost Riemann solitons with several kinds of potential vector fields on the deformed spaces have been characterized.
Abstract : Let $A$ be a commutative integral domain with identity element and $S$ a multiplicatively closed subset of $A$. In this paper, we introduce the concept of $S$-valuation domains as follows. The ring $A$ is said to be an $S$-valuation domain if for every two ideals $I$ and $J$ of $A$, there exists $s\in S$ such that either $sI\subseteq J$ or $sJ\subseteq I$. We investigate some basic properties of $S$-valuation domains. Many examples and counterexamples are provided.
Abstract : For a fixed parametrization of a curve in an orientable two-dimensional Riemannian manifold, we introduce and investigate a new frame and curvature function. Due to the way of defining this new frame as being the time-dependent rotation in the tangent plane of the standard Frenet frame, both these new tools are called flow.
Abstract : In this paper, our focus is on exploring value sharing \linebreak problems related to a transcendental entire function $f$ and its associated differential-difference polynomials. We aim to establish some results which are related to differential-difference counterpart of the Br\"{u}ck conjecture.
Abstract : In this paper, we prove the Hyers-Ulam stability and Mittag-Leffler-Hyers-Ulam stability of a differential equation of Logistic growth in a population by applying Laplace transforms method.
Abstract : We are interested in the gradient flow of $\alpha$ energy potential. We provide basic estimates and study asymptotic behaviors for the case $N=2, \ldots, 5$.
Nour Elhouda Djaa, Abderrahim Zagane
Commun. Korean Math. Soc. 2022; 37(3): 865-879
https://doi.org/10.4134/CKMS.c210207
Kanwal Jabeen, Afis Saliu
Commun. Korean Math. Soc. 2022; 37(4): 995-1007
https://doi.org/10.4134/CKMS.c210273
Shiroyeh Payrovi, Yasaman Sadatrasul
Commun. Korean Math. Soc. 2023; 38(1): 39-46
https://doi.org/10.4134/CKMS.c210390
Abdellah Mamouni, Lahcen Oukhtite, Mohammed Zerra
Commun. Korean Math. Soc. 2023; 38(1): 79-87
https://doi.org/10.4134/CKMS.c220004
Abdelhadi Zaim
Commun. Korean Math. Soc. 2023; 38(4): 1309-1320
https://doi.org/10.4134/CKMS.c230014
Ali Benhissi, Abdelamir Dabbabi
Commun. Korean Math. Soc. 2023; 38(3): 663-677
https://doi.org/10.4134/CKMS.c220230
Tarak Mandal, Avijit Sarkar
Commun. Korean Math. Soc. 2023; 38(3): 865-880
https://doi.org/10.4134/CKMS.c220145
soufiane Benkouider, Abita Rahmoune
Commun. Korean Math. Soc. 2023; 38(3): 943-966
https://doi.org/10.4134/CKMS.c220225
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