eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
1
10
10.22034/kjm.2018.67030
67030
On a Classification of Almost $alpha $-Cosymplectic Manifolds
İrem Erken
irem.erken@btu.edu.tr
1
Faculty of Engineering and Natural Sciences, Department of Mathematics, Bursa Technical University, Bursa, Turkey.
The object of the present paper is to study almost $alpha $-cosymplectic manifolds. We consider projectively flat, conformally flat, and concircularly flat almost $alpha $-cosymplectic manifolds (with the $eta $-parallel tensor field $phi h$) and get some new properties. We conclude the paper by giving an example of $alpha $-Kenmotsu manifold, which verifies our results.
http://www.kjm-math.org/article_67030_b36cd9107ed71f514da1f1c232d7e881.pdf
Almost α-Cosymplectic manifold
projectively flat
conformally flat
concircularly flat
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
11
20
10.22034/kjm.2018.73499
73499
Exponential Stability Analysis for Delay-Differential Systems of Neutral Type with an LMI Approach
Veerakyathaiah Umesha
vumeshakumar@gmail.com
1
Spirangaiah Padmanabhan
padmanabhanrnsit@gmail.com
2
P. Baskar
pbaskar83@yahoo.com
3
Muhammad Syed Ali
syedgru@gmail.com
4
Department of Mathematics, Dayananda sagar college of Engineering, Kumaraswamy layout, Bangalore, Karnataka, India.
Department of Mathematics, R N S I T, Uttarahalli-Kengeri Road, Bangalore, Karnataka, India.
Department of Mathematics, New Horizon college of Engineering, Bangalore, Karnataka, India.
Department of Pure Mathematics, Thiruvalluvar University, Vellore 632- 115, Tamilnadu, India.
In this paper for neutral delay differential systems, the problem of determining the exponential stability is investigated. Based on the Lyapunov method, we present some useful criteria of exponential stability for the derived systems. The stability criterion is formulated in terms of linear matrix inequality (LMI),which can be easily solved by using the MATLAB LMI toolbox. Numerical examples are included to illustrate the proposed method.
http://www.kjm-math.org/article_73499_aafcf9d48fb015be832da281da3efe11.pdf
Neutral system
exponential stability
Lyapunov method
linear matrix inequality (LMI)
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
21
39
10.22034/kjm.2018.73593
73593
The Approximate Solutions of Fractional Integro-Differential Equations by Using Modified Adomian Decomposition Method
Ahmed Hamoud
drahmed985@yahoo.com
1
Kirtiwant Ghadle
drkp.ghadle@gmail.com
2
Shakir Atshan
s11h32@yahoo.com
3
Department of Mathematics Faculty of Education and Science, Taiz University, Taiz, Yemen.
Department of Mathematics, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad 431-004, India.
Department of Mathematics, Thi Qar Directorates of Education, Ministry of Education, Iraq.
The main object of the present paper is to study the behavior of the approximated solutions of the Caputo fractional Volterra-Fredholm integro-differential equations by using modified Adomian decomposition method. Moreover, we discuss some new existence, uniqueness, and convergence results. Finally, an example is included to demonstrate the validity and applicability of the proposed technique.
http://www.kjm-math.org/article_73593_6dc1e8da8bef248712e90632993e6c0c.pdf
Modified Adomian decomposition method
Caputo fractional derivative
fractional Volterra--Fredholm integro-differential equation
approximate solution
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
40
59
10.22034/kjm.2018.73854
73854
Dynamic Response of an Elastically Connected Double Non-Mindlin Plates with Simply-Supported End Condition due to Moving Load
Jacob Gbadeyan
jagbadeyan@gmail.com
1
Oluwatayo Ogunmiloro
oluwatayo.ogunmiloro@eksu.edu.ng
2
Sunday Fadugba
classbillboard.fadugba@gmail.com
3
Department of Mathematics, University of Ilorin, Ilorin, Kwara-State, Nigeria.
Department of Mathematics, Ekiti - State University(EKSU), Ado-Ekiti, Ekiti - State, Nigeria.
Department of Mathematics, Ekiti - State University(EKSU), Ado-Ekiti, Ekiti - State, Nigeria.
In this paper, the dynamic response of two identical parallel non-mindlin (i.e., not taking into account the effect of shear deformation and rotatory inertia) plates which are elastically connected and subjected to a constant moving load is considered. The fourth order coupled partial differential governing equations is formulated and solved, using an approximate analytical method by assuming; firstly, a series solution later on treating the resulting coupled second order ordinary differential equations with an asymptotic method of Struble. The differential transform method, being a semi-analytical technique, is applied to the reduced coupled second order ordinary differential equations, to get a non-oscillatory series solution. An after treatment technique, comprising of the Laplace transform and Pade approximation techniques, is finally used via MAPLE ODE solver to make the series solution oscillatory. The dynamic deflections of the upper and lower plates are presented in analytical closed forms. The effect of the moving speed of the load and the elasticity of the elastic layer on the dynamic responses of the double plate systems is graphically shown and studied in details. The graphs of the plate's deflections for different speed parameters were plotted. It is however observed that the transverse deflections of each of the plates increase with an increase in different values of velocities for the moving load for a fixed time $t$.
http://www.kjm-math.org/article_73854_83d31b7b005db96ff9db98c737010e46.pdf
Moving load
non-mindlin
simply-supported
Struble's method
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
60
68
10.22034/kjm.2018.74220
74220
On T-Extensions of Abelian Groups
Aliakbar Alijani
alijanialiakbar@gmail.com
1
Hossein Sahleh
sahleh@guilan.ac.ir
2
Mollasadra Technical and Vocational College, Technical and Vocational University, Ramsar, Iran.
Department of Mathematics, University of Guilan, P. O. Box 1914, Rasht, Iran.
Let $Re$ be the category of all discrete abelian groups, and let $cal{L}$ be the category of all locally compact abelian (LCA) groups. For a group $Gin cal{L}$, the maximal torsion subgroup of $G$ is denoted by $tG$. A short exact sequence $0to Astackrel{phi}{to} Bstackrel{psi}{to}Cto 0$ in $Re$ is said to be a t-extension if $0to tAstackrel{phi}{to} tBstackrel{psi}{to}tCto 0$ is a short exact sequence. We show that the set of all t-extensions of $A$ by $C$ is a subgroup of $Ext(C,A)$, which contains $Pext(C,A)$ for discrete abelian groups $A$ and $C$. We establish conditions under which the t-extensions split and determine those groups in $Re$ which are t-injective or t-projective in $Re$. Finally we determine the compact groups $G$ in $cal{L}$ such that every pure extension of $G$ by a compact connected group $Cin cal{L}$ splits.
http://www.kjm-math.org/article_74220_a9f5d5879c28658ed606d177fed55aa0.pdf
T-extensions
extensions
pure extensions
locally compact abelian groups
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
69
78
10.22034/kjm.2018.75278
75278
On Randers Change of Generalized $m$th Root Metric
Manoj Kumar
mkvermabhu@gmail.com
1
DST-Centre for Interdisciplinary Mathematical Sciences, Institute of Science, Banaras Hindu University, Varanasi-221005, India.
In the present paper, we find a condition under which a Finsler space with Randers change of generalized $m$th root metric is projectively related to an $m$th root metric. Then we find a condition under which Randers change of generalized $m$th root Finsler metric is locally projectively flat and also find a condition for locally dually flatness.
http://www.kjm-math.org/article_75278_d06809e915d950b5df2806938c6d5b6f.pdf
Finsler space
Randers change of generalized $m$th root metrics
projectively related metrics
locally projectively flat metric
locally dually flat metric
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
79
88
10.22034/kjm.2019.81212
81212
Ruscheweyh-Type Harmonic Functions Defined By $q$- Differential Operators
Gangadharan Murugusundaramoorthy
gmsmoorthy@yahoo.com
1
Jay Jahangiri
jjahangi@kent.edu
2
Department of Mathematics, School of Advanced Sciences, Vellore Institute of Technology, Vellore - 632014, India.
Mathematical Sciences, Kent State University, Kent, Ohio, U.S.A.
A class of Ruscheweyh-type harmonic functions is defined, using $q$-differential operators and sufficient coefficient conditions for this class is determined. We then consider a subclass of the aforementioned class consisting of functions with real coefficients and obtain necessary and sufficient coefficient bounds, distortion theorem, extreme points, and convex combination conditions for such class. It is shown that the classes of functions considered in this paper contain various well-known as well as new classes of harmonic functions.
http://www.kjm-math.org/article_81212_6cf18940b12156412dcfac780d5c4d20.pdf
Univalent
harmonic starlike
$q$- differential operators
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
89
104
10.22034/kjm.2019.81221
81221
Almost conformal Ricci solitons on $f$-Kenmotsu Manifolds
Shyamal Hui
skhui@math.buruniv.ac.in
1
Sunil Yadav
prof_sky16@yahoo.com
2
Akshoy Patra
akshoyp@gmail.com
3
Department of Mathematics, The University of Burdwan, Golapbag, Burdwan – 713104, West Bengal, India.
Department of Mathematics, Poornima College of Engineering, ISI-6, RIICO Institutional Area, Sitapura, Jaipur – 302022, Rajasthan, India.
Department of Mathematics, Govt. College of Engineering and Technology, Berhampur, Murshidabad – 742101, West Bengal, India.
The object of the present paper is to study the $phi $-Ricci symmetric, locally $phi $-Ricci symmetric and cyclic Ricci parallel three-dimensional $f$-Kenmotsu manifold bearing the function $f$ being constant. We have considered almost conformal Ricci soliton on the three-dimensional $f$-Kenmostu manifold and deduced the condition for an almost conformal Ricci soliton, which becomes conformal Ricci soliton. Finally, examples on three-dimensional $f$-Kenmotsu manifold depending on nature of $f$ are constructed to illustrate the results.
http://www.kjm-math.org/article_81221_ef73fb5317c2abd196bf85fc43cda852.pdf
$f$-Kenmotsu manifold
almost conformal Ricci soliton
$phi $-symmetric
cyclic Ricci parallel
torqued vector field
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
105
112
10.22034/kjm.2019.81222
81222
On The Stability of The Quasi-Linear Implicit Equations in Hilbert Spaces
Mehdi Benabdallah
mehdibufarid@yahoo.fr
1
Mohamed Hariri
haririmohamed22@yahoo.fr
2
Department of Mathematics, Faculty of Math and Computer, USTOran, 31000, Algeria
Department of Mathematics, University of Djillali Liabes, Sidi Bel-Abbes, 22000, Algeria.
We use the generalized theorem of Liapounov to obtain some necessary and sufficient conditions for the stability of the stationary implicit equation $$Ax'(t)=Bx(t) ,quad tgeq 0 ,$$ where $A$ and $B$ are bounded operators in Hilbert spaces. The achieved results can be applied to the stability for the quasi-linear implicit equation $$Ax'(t)=Bx(t)+theta(t,x(t)),quad tgeq 0 .$$
http://www.kjm-math.org/article_81222_42e39894a1979bb86b55e195a4835a6e.pdf
exponential stability
operator theory
implicit equations
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
113
124
10.22034/kjm.2019.81223
81223
On Approximation by $(p,q)$-Meyer-König-Zeller Durrmeyer Operators
Honey Sharma
pro.sharma.h@gmail.com
1
Cheena Gupta
guptacheena21@gmail.com
2
Ramapati Maurya
ramapatimaurya@gmail.com
3
Department of Mathematics, Gulzar Group of Institutes, Punjab, India.
I K G Punjab Technical University, Punjab, India.
I K G Punjab Technical University, Punjab, India; Department of Mathematics, Manav Rachna University, Haryana, India.
In this paper, we introduce a Durrmeyer type modification of Meyer-König-Zeller operators based on $(p,q)$-integers. The rate of convergence of these operators is explored with the help of Korovkin type theorems. We establish some direct results for proposed operators. We also obtain statistical approximation properties of operators. In the last section, we show the rate of convergence of $(p,q)$-Meyer-König-Zeller Durrmeyer operators for some functions by means of MATLAB programming.
http://www.kjm-math.org/article_81223_7fe57d6463c07a48bf3f40586cfbc49b.pdf
$(p, q)$-Calculus, $(p, q)$-Meyer-König-Zeller operator
Modulus of continuity
Peetre $K$-functional
statistical convergence
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
125
139
10.22034/kjm.2019.81226
81226
On Two Generation Methods for The Simple Linear Group $PSL(3,5)$
Ayoub Basheer
ayoubbasheer@gmail.com
1
Thekiso Seretlo
thekiso.seretlo@ul.ac.za
2
School of Mathematical and Computer Sciences, University of Limpopo (Turfloop), P Bag X1106, Sovenga 0727, South Africa
School of Mathematical and Computer Sciences, University of Limpopo (Turfloop), P Bag X1106, Sovenga 0727, South Africa
A finite group $G$ is said to be $(l,m, n)$-generated, if it is a quotient group of the triangle group $T(l,m, n) = left<x,y, z|x^{l} = y^{m} = z^{n} = xyz = 1right>.$ In [Nova J. Algebra and Geometry, 2 (1993), no. 3, 277--285], Moori posed the question of finding all the $(p,q,r)$ triples, where $p, q,$ and $r$ are prime numbers, such that a nonabelian finite simple group $G$ is $(p,q,r)$-generated. Also for a finite simple group $G$ and a conjugacy class $X$ of $G,$ the rank of $X$ in $G$ is defined to be the minimal number of elements of $X$ generating $G.$ In this paper, we investigate these two generational problems for the group $PSL(3,5),$ where we will determine the $(p,q,r)$-generations and the ranks of the classes of $PSL(3,5).$ We approach these kind of generations using the structure constant method. GAP [The GAP Group, GAP-Groups, Algorithms, and Programming, Version 4.9.3; 2018. (http://www.gap-system.org)] is used in our computations.
http://www.kjm-math.org/article_81226_0b11fe80a831ac221e4f219d8e01381f.pdf
Conjugacy classes
$(p, q, r)$-generation
rank
structure constant
eng
Tusi Mathematical Research Group (TMRG) and Department of Pure Mathematics, Ferdowsi University of Mashhad (in cooperation with
The Center of Excellence in Analysis on Algebraic Structures)
Khayyam Journal of Mathematics
2423-4788
2423-4788
2019-01-01
5
1
140
149
10.22034/kjm.2019.81231
81231
Coefficients of Bi-Univalent Functions Involving Pseudo-Starlikeness Associated with Chebyshev Polynomials
Ibrahim Awolere
awolereibrahim01@gmail.com
1
Abiodun Oladipo
atoladipo@lautech.edu.ng
2
Department of Mathematics, Emmanuel Alayande College of Education, P. M. B. 1010, Oyo, Oyo State, Nigeria.
Department of Pure and Applied Mathematics, Ladoke Akintola University of Tecchnology, Ogbomoso, Oyo State, Nigeria.
In the present paper, a new subclass of analytic and bi-univalent functions by means of pseudo starlike function, activation function and Chebyshev polynomials are introduced. Coefficient bounds for functions belonging to the said subclass are obtained. Relevance connection of our class to second Hankel determinants is established.
http://www.kjm-math.org/article_81231_3bd1e952383059c6791a5d546ecb0d03.pdf
univalent functions
Chebyshev polynomials
pseudo starlike function
Hankel determinant