Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701The (p,q,r)-generations of the alternating group A_1116518612305910.22034/kjm.2020.205718.1600ENAyoub Basheer MohammedBasheerUniversity of LimpopoMalebogoMotalaneUniversity of Limpopo.0000-0003-4484-4355Thekiso TrevorSeretloSchool of Mathematical and Computer
Sciences, University of Limpopo (Turfloop), P Bag X1106, Sovenga
0727, South AfricaJournal Article20191019A finite group G is called (l,m, n)-generated}, if it is a quotient group of the triangle group T(l,m, n) = <x, y, z|x^l = y^m = z^n = xyz = 1>. In [23], Moori posed the question of finding all the (p,q,r) triples, where p, q and r are prime numbers, such that a non-abelian finite simple group G is a (p,q,r)-generated. In this paper we establish all the (p,q,r)-generations of the alternating group A_11.$ GAP [14] and the Atlas of finite group representations[28] are used in our computations.http://www.kjm-math.org/article_123059_118cddb09270ac12afbf0585c55b700a.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701The correspondence of Fusion frames and frames In Hilbert $C^*$-modules and finite Gabor Fusion frames18720012306010.22034/kjm.2020.169670.1308ENRajab AliKamyabi-GolFerdowsi University of MashhadMozhganMohammadpourDepartment of Pure Mathematics, Faculty of Mathematical sciences, Ferdowsi University of Mashhad, IranJournal Article20190127In this paper, we show that fusion frames in the finite dimensional Hilbert space $H$ correspond to frames in the Hilbert $C^*$-module $mathcal{B}left(mathbb{C}^nright)$. Moreover, we show that every tight fusion frame and Reisz fusion basis in $mathbb{C}^n$ correspond to a tight frame and Reisz basis in the Hilbert $C^*$-module $mathcal{B}left(mathbb{C}^nright)$ respectively. Then, we use this fact to characterize the dual of Reisz fusion basis. Finally, we introduce Gabor fusion frames as a new notion.http://www.kjm-math.org/article_123060_549a8420805639b552b28a7afb2b87be.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701Some properties of geodesic $(alpha,E)$-preinvex functions on Riemannian manifolds20121012306110.22034/kjm.2020.220226.1717ENAbsos AliShaikhUniversity of BurdwanChandan KumarMondalUniversity of BurdwanRavi P.AgarwalDepartment of Mathematics, Texas A&amp;M University, TexasJournal Article20200216In this article, we have introduced the concept of textit{geodesic $(alpha,E)$-invex set} and by using this concept the notion of textit{geodesic $(alpha,E)$-preinvex functions} and textit{geodesic $(alpha,E)$-invex functions} are developed on a Riemannian manifold. Moreover, several properties and results are deduced within aforesaid functions. An example is also constructed to illustrate the definition of geodesic $(alpha,E)$-invex set. We have also established an important relation between geodesic $(alpha,E)$-preinvex function and geodesic $(alpha,E)$-invex function in a complete Riemannian manifold.http://www.kjm-math.org/article_123061_bcd8001b7bb15ca48ab4e91b0bb14fd8.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701Multi-dimensional wavelets on Sobolev spaces21121813007510.22034/kjm.2021.202782.1576ENFatemehEsmaeelzadehIslamic Azad University, Bojnourd BranchJournal Article20190924In this paper, for admissible and integrable function $psi$ in $L^2(mathbb{R}^n)$, the multi-dimensional continuous wavelet transform on Sobolev spaces is defined. The inversion formula for this transform on Sobolev spaces is established and as a result it is concluded that there is an isometry of Sobolev spaces $H_s(mathbb{R}^n)$ into $H_{0,s}(mathbb{R}^n times mathbb{R}^+_0times S^{n-1})$, for arbitrary real $s$. Also, among other things, it is shown that the range of this transform is a reproducing kernel Hilbert space and the reproducing kernel is found.http://www.kjm-math.org/article_130075_9a177af8e6f9787ecd973580817508db.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701Primeness of simple modules over path algebras and Leavitt path algebras21923113007610.22034/kjm.2021.203331.1578ENRisnawitaRisnawitaInstitut Teknologi BandungIrawatiIrawatiFaculty of Mathematics and Natural Sciences, Institut Teknologi Bandung,
Jalan Ganesa 10 Bandung 40132, Indonesia.Intan MuchtadiAlamsyahFaculty of Mathematics and Natural Sciences, Institut Teknologi Bandung,
Jalan Ganesa 10 Bandung 40132, Indonesia.0000-0001-7059-3196Journal Article20190929Let K be a field and E be a directed graph, called quiver in the<br />following, and let A = KE be the path algebra that corresponds to E with<br />coefficients in K. An A-module M is a c-prime module in the sense that rm = 0<br />for one m in M and r in A implies that either r annihilates all M or m = 0. In<br />this paper, we prove that for any acyclic graph E, an A-module M is c-prime<br />if and only if it is simple. The primeness of simple modules over Leavitt path<br />algebras is also discussed. We prove that some classes of simple modules over<br />Leavitt path algebras, are not c-prime modules.http://www.kjm-math.org/article_130076_103bbc02d81ad766f14dd138a47f29a8.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701Modulation invariant spaces on locally compact abelian groups23224013036210.22034/kjm.2020.230232.1827ENMahdiMortazavizadehFerdowsi university of MashhadReihanehRaisi TousiFerdowsi University of MashhadJournal Article20200507We define and investigate modulation invariant spaces on a locally compact abelian group $G$ with respect to a closed subgroup of the dual group $widehat{G}$. Using a range function approach, we establish a characterization of modulation invariant spaces. Finally, we define a metric on the collection of all modulation invariant spaces and study some topological properties of the metric space.http://www.kjm-math.org/article_130362_5c9fdf9f889b12fc3a991c2cf05a3f85.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701Permanence and stability of multi-species nonautonomous Lotka--Volterra competitive systems with delays and feedback controls on time scales24125613078810.22034/kjm.2021.220759.1725ENMahammadKhuddushDepartment of Applied Mathematics,
Andhra University,
Visakhapatnam,india-5300030000-0002-1236-8334KapulaRajendra PrasadDepartment of Applied Mathematics,
Andhra University.Journal Article20200221In this paper, we consider a multi-species Lotka-Volterra type competitive system with delays and feedback controls on time scales. A general criteria on the permanence is established and then by constructing suitable Lyapunov functionals, sufficient conditions are derived for the existence and<br />uniform asymptotic stability of unique positive almost periodic solution of the system.http://www.kjm-math.org/article_130788_8326a9d9ee8d7740b350002a6be69d1d.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701On the discrete group analysis for the exact solutions of some classes of the nonlinear Abel and Burgers equations25726513084110.22034/kjm.2021.224570.1751ENParvizDaraniaDepartment of Mathematics, Urmia university&lrm; P.O.Box 165&lrm; &lrm;Urmia-Iran0000-0003-4996-6925Journal Article20200326This article presents an account of the fundamentals of the discrete<br />group approach for analysis and integration of practical<br />differential equations. In this paper, by means of appropriate<br />transformations, the nonlinear Burgers equation is transformed into<br />the other class of the second-order differential equation of the<br />Emden-Fowler type and this Emden-Fowler equation reduces to the<br />nonlinear Abel equations. This approach shows that, under this<br />transformations of discrete group, the solution of reference<br />equation can be transformed into the solution of the transformed<br />equation. Under such a conditions, we approach to the determine some<br />solutions for the Abel, Burgers, Emden-Fowler and heat equations.http://www.kjm-math.org/article_130841_f5850a8d48e351b2b4da5292cbdc65f7.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701Isbell convexity in fuzzy quasi-metric spaces26627813088810.22034/kjm.2021.227905.1801ENHopeSabaoUniversity of the Witwatersrand0000-0002-8649-5635Olivier OlelaOtafuduNorth-West University, Potchefstroom Campus
Potchefstroom 2520
SOUTH AFRICAJournal Article20200421We introduce the concept of Isbell convexity in fuzzy quasi-metric spaces, which we call fuzzy Isbell convexity. This idea extends Isbell convexity (or q-hyperconvexity) in quasi-metric spaces to fuzzy quasi metric spaces. We show that fuzzy Isbell convexity is preserved by certain $F$-bounded subsets and the space of non-negative function pairs of the fuzzy quasi-metric space.http://www.kjm-math.org/article_130888_6f5365296ff0339d167552c78991de5b.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701Iterative regularization method for an abstract inverse Goursat problem27929713134510.22034/kjm.2020.237076.1900ENMohamed Sief EddineMezianiEcole Normale Supérieure de l'Enseignement Technologique, Azzaba, Skikda, Algeria.
Applied Mathematics Laboratory, University Badji Mokhtar Annaba.NadjibBoussetilaDepartment of Mathematics, 8 Mai 1945 Guelma University, P.O.Box 401, Guelma 24000, AlgeriaFaouziaRebbaniEcole Supérieure de Technologies Industrielles, Annaba, Algeria.
Applied Mathematics Laboratory, University Badji Mokhtar Annaba.AbderafikBenrabahUniversity 8 Mai 1945 Guelma, Algeria.
Applied Mathematics Laboratory, University Badji Mokhtar Annaba.Journal Article20200627In this paper we deal with a problem of identification of an unknown source in the abstract inverse Goursat problem with two-time variables. We show that the considered problem is ill-posed according to the Hadamard sense. That is, the solution does not depend continuously on the data. In order to overcome the instability of the solution, we propose a regularization method via an iterative procedure, with the help of an extra measurement at an internal point. Some convergence results are established under a priori bound assumptions on the exact solution. Finally, numerical tests are presented to illustrate the accuracy and efficiency of the proposed regularization method.http://www.kjm-math.org/article_131345_efc2a63e428e10c33fdf6d2576031143.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701Metallic structures on the tangent bundle of P-Sasakian manifolds29830913134610.22034/kjm.2021.242375.1950ENShahroudAzamiDepartment of pure Mathematics, Imam Khomeini international university,
Qazvin, IranJournal Article20200803In this article, we introduce some metallic structures on the tangent bundle of a P-Sasakian manifold by complete lift, horizontal lift and vertical lift of a P-Sasakian structure $ ( phi, eta, xi ) $ on tangent bundle. Then we investigate the integrability and parallelity of these metallic structures.http://www.kjm-math.org/article_131346_760d97377a981f96bd4684d6050012d0.pdfDepartment of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with the Center of Excellence in Analysis on Algebraic Structures and Tusi Mathematical Research Group)Khayyam Journal of Mathematics2423-47887220210701Almost Kenmotsu manifolds admitting certain vector fields31032013134710.22034/kjm.2020.235131.1873ENDibakarDeyDepartment of Pure Mathematics, University of Calcutta, India.0000-0001-8992-6501PradipMajhiDepartment of Pure Mathematics, University of Calcutta,
35, Ballygaunge Circular Road,
Kolkata 700019,
West Bengal, India0000-0002-4364-1815Journal Article20200613The object of the present paper is to characterize almost Kenmotsu manifolds admitting holomorphically planar conformal vector (in short, HPCV) fields. It is shown that an almost Kenmotsu manifold $M^{2n+1}$ admitting a non-zero HPCV field $V$ such that $V$ is pointwise collinear with the Reeb vector field $xi$ is locally a warped product of an almost Kaehler manifold and an open interval. Further, if an almost Kenmotsu manifold with constant $xi$-sectional curvature admits a non-zero HPCV field $V$, then $M^{2n+1}$ is locally a warped product of an almost Kaehler manifold and an open interval. Moreover, a $(k,mu)'$-almost Kenmotsu manifold admitting a HPCV field $V$ such that $phi V neq 0$ is either locally isometric to $mathbb{H}^{n+1}(-4)$ $times$ $mathbb{R}^n$ or $V$ is an eigenvector of $h'$.http://www.kjm-math.org/article_131347_bdd8045bc7b7de265443a172ec53739b.pdf