Communications of the
Korean Mathematical Society
CKMS
ISSN(Print) 1225-1763
ISSN(Online) 2234-3024
Most Read
HOME
VIEW ARTICLES
Most Read
VIEW ARTICLES
Most Read
-
2022-10-31
The independence and independent dominating numbers of the total graph of a finite commutative ring
Baha' Abughazaleh, Omar AbedRabbu AbughneimAbstract : Let $R$ be a finite commutative ring with nonzero unity and let $Z(R)$ be the zero divisors of $R$. The total graph of $R$ is the graph whose vertices are the elements of $R$ and two distinct vertices $x,y\in R$ are adjacent if $x+y\in Z(R)$. The total graph of a ring $R$ is denoted by $\tau (R)$. The independence number of the graph $\tau (R)$ was found in \cite{Nazzal}. In this paper, we again find the independence number of $\tau (R)$ but in a different way. Also, we find the independent dominating number of $\tau (R)$ . Finally, we examine when the graph $\tau (R)$ is well-covered.
-
2023-04-30
Simple formulations on circulant matrices with alternating Fibonacci
Sugi GuritmanAbstract : In this article, an alternating Fibonacci sequence is defined from a second-order linear homogeneous recurrence relation with constant coefficients. Then, the determinant, inverse, and eigenvalues of the circulant matrices with entries in the first row having the formation of the sequence are formulated explicitly in a simple way. In this study, the method for deriving the formulation of the determinant and inverse is simply using traditional elementary row or column operations. For the eigenvalues, the known formulation from the case of general circulant matrices is simplified by considering the specialty of the sequence and using cyclic group properties. We also propose algorithms for the formulation to show how efficient the computations are.
-
2023-04-30
Characterizations of (Jordan) derivations on Banach algebras with local actions
Jiankui Li, Shan Li, Kaijia LuoAbstract : Let $\mathcal{A}$ be a unital Banach $*$-algebra and $\mathcal{M}$ be a unital $*$-$\mathcal{A}$-bimodule. If $W$ is a left separating point of $\mathcal{M}$, we show that every $*$-derivable mapping at $W$ is a Jordan derivation, and every $*$-left derivable mapping at $W$ is a Jordan left derivation under the condition $W \mathcal{A}=\mathcal{A}W$. Moreover we give a complete description of linear mappings $\delta$ and $\tau$ from $\mathcal{A}$ into $\mathcal{M}$ satisfying $\delta(A)B^*+A\tau(B)^*=0$ for any $A, B\in \mathcal{A}$ with $AB^*=0$ or $\delta(A)\circ B^*+A\circ\tau(B)^*=0$ for any $A, B\in \mathcal{A}$ with $A\circ B^*=0$, where $A\circ B=AB+BA$ is the Jordan product.
-
2023-04-30
On the Characterization of $F_{0}$-spaces
Mahmoud BenkhalifaAbstract : Let $X$ be a simply connected rationally elliptic space such that $H^{2}(X; {\mathbb Q})\neq0$. In this paper, we show that if $ H^{2n}(X^{[2n-2]}; {\mathbb Q})=0$ or if $\pi_{2n}(X^{2n}) \otimes {\mathbb Q}=0$ for all $n$, then $X$ is an $F_{0}$-space.
-
2023-10-31
Equality in degrees of compactness: Schauder's theorem and $s$-numbers
Asuman Guven Aksoy, Daniel Akech ThiongAbstract : We investigate an extension of Schauder's theorem by studying the relationship between various $s$-numbers of an operator $T$ and its adjoint $T^*$. We have three main results. First, we present a new proof that the approximation number of $T$ and $T^*$ are equal for compact operators. Second, for non-compact, bounded linear operators from $X$ to $Y$, we obtain a relationship between certain $s$-numbers of $T$ and $T^*$ under natural conditions on $X$ and $Y$. Lastly, for non-compact operators that are compact with respect to certain approximation schemes, we prove results for comparing the degree of compactness of $T$ with that of its adjoint $T^*$.
-
2023-04-30
Maximal chain of ideals and $n$-maximal ideal
Hemin A. Ahmad, Parween A. HummadiAbstract : In this paper, the concept of a maximal chain of ideals is introduced. Some properties of such chains are studied. We introduce some other concepts related to a maximal chain of ideals such as the $n$-maximal ideal, the maximal dimension of a ring $S$ $(M.\dim(S))$, the maximal depth of an ideal $K$ of $S$ $(M.d(K))$ and maximal height of an ideal $K(M.d(K))$.
-
2022-07-31
Study of gradient solitons in three dimensional Riemannian manifolds
Gour Gopal Biswas, Uday Chand DeAbstract : We characterize a three-dimensional Riemannian manifold endowed with a type of semi-symmetric metric $P$-connection. At first, it is proven that if the metric of such a manifold is a gradient $m$-quasi-Einstein metric, then either the gradient of the potential function $psi$ is collinear with the vector field $P$ or, $lambda=-(m+2)$ and the manifold is of constant sectional curvature $-1$, provided $Ppsi eq m$. Next, it is shown that if the metric of the manifold under consideration is a gradient $ho$-Einstein soliton, then the gradient of the potential function is collinear with the vector field $P$. Also, we prove that if the metric of a 3-dimensional manifold with semi-symmetric metric $P$-connection is a gradient $omega$-Ricci soliton, then the manifold is of constant sectional curvature $-1$ and $lambda+mu=-2$. Finally, we consider an example to verify our results.
-
2022-07-31
Solitons of K"{A}hlerian Norden space-time manifolds
Praveena Manjappa Mundalamane, Bagewadi Channabasappa Shanthappa, Mallannara Siddalingappa SiddeshaAbstract : We study solitons of K"{a}hlerian Norden space-time manifolds and Bochner curvature tensor in almost pseudo symmetric K"{a}hlerian space-time manifolds. It is shown that the steady, expanding or shrinking solitons depend on different relations of energy density/isotropic pressure, the cosmological constant, and gravitational constant.
-
2022-07-31
Infinitely many homoclinic solutions for damped vibration systems with locally defined potentials
Wafa Selmi, Mohsen TimoumiAbstract : In this paper, we are concerned with the existence of infinitely many fast homoclinic solutions for the following damped vibration system $$ddot{u}(t)+q(t)dot{u}(t)-L(t)u(t)+ abla W(t,u(t))=0, forall tinmathbb{R}, leqno(1)$$ where $qin C(mathbb{R},mathbb{R})$, $Lin C(mathbb{R},mathbb{R}^{N^{2}})$ is a symmetric and positive definite matix-valued function and $Win C^{1}(mathbb{R} imesmathbb{R}^{N},mathbb{R})$. The novelty of this paper is that, assuming that $L$ is bounded from below unnecessarily coercive at infinity, and $W$ is only locally defined near the origin with respect to the second variable, we show that $(1)$ possesses infinitely many homoclinic solutions via a variant symmetric mountain pass theorem.
-
2023-01-31
Geometric inequalities for warped products submanifolds in generalized complex space forms
Mohd Aquib, Mohd Aslam, Michel Nguiffo Boyom, Mohammad Hasan ShahidAbstract : In this article, we derived Chen's inequality for warped product bi-slant submanifolds in generalized complex space forms using semi-symmetric metric connections and discuss the equality case of the inequality. Further, we discuss non-existence of such minimal immersion. We also provide various applications of the obtained inequalities.
Most Read
-
Pascal's hexagon theorem reproved by elementary tools only
Insong Choe
Commun. Korean Math. Soc. 2022; 37(4): 989-993
https://doi.org/10.4134/CKMS.c210397 -
Transversal lightlike submersions from indefinite Sasakian manifolds onto lightlike manifolds
Shiv Sharma Shukla, Vipul Singh
Commun. Korean Math. Soc. 2023; 38(4): 1191-1213
https://doi.org/10.4134/CKMS.c220309 -
Functions subordinate to the exponential function
Priya G. Krishnan, Vaithiyanathan Ravichandran, Ponnaiah Saikrishnan
Commun. Korean Math. Soc. 2023; 38(1): 163-178
https://doi.org/10.4134/CKMS.c220087 -
A simple proof for a result on $n$-Jordan homomorphisms
Choonkil Park, Abbas Zivari-Kazempour
Commun. Korean Math. Soc. 2023; 38(2): 487-490
https://doi.org/10.4134/CKMS.c220136
Most Downloaded
-
The measurability of Hewitt-Stromberg measures and dimensions
Zied Douzi, Bilel Selmi, Haythem Zyoudi
Commun. Korean Math. Soc. 2023; 38(2): 491-507
https://doi.org/10.4134/CKMS.c220154 -
Oriented transformations on a finite chain: another description
Vítor Hugo Fernandes
Commun. Korean Math. Soc. 2023; 38(3): 725-731
https://doi.org/10.4134/CKMS.c220272 -
Some classes of operators related to $(m, n)$-paranormal and $(m, n)^*$-paranormal operators
SHINE LAL ENOSE, RAMYA PERUMAL, PRASAD THANKARAJAN
Commun. Korean Math. Soc. 2023; 38(4): 1075-1090
https://doi.org/10.4134/CKMS.c220355 -
Fractional integration and differentiation of the $(p,q)$--extended modified Bessel function of the second kind and integral transforms
Purnima Chopra, Mamta Gupta, Kanak Modi
Commun. Korean Math. Soc. 2023; 38(3): 755-772
https://doi.org/10.4134/CKMS.c220132
Editorial Office
✕
CKMS
© 2022. The Korean Mathematical Society. Powered by INFOrang Co., Ltd