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 Mathematics
24234788
6
1
2020
01
01
On a New Class of Bernstein Type Operators Based on Beta Function
1
15
EN
Dhawal
J.
Bhatt
Applied Mathematics and Humanities Department, Sardar Vallabhbhai National Institute of Technology, Ichchhanath Mahadev Dumas Road, Surat395
007 (Gujarat), India.
dhawal.bhatt@sxca.edu.in
Vishnu
Narayan
Mishra
0000000221597710
Department of Mathematics, Indira Gandhi National Tribal University, Lalpur, Amarkantak, Anuppur, (Madhya Pradesh) 484 887, India.
vishnunarayanmishra@gmail.com
Ranjan
Kumar
Jana
Applied Mathematics and Humanities Department, Sardar Vallabhbhai National Institute of Technology, Ichchhanath Mahadev Dumas Road, Surat395
007 (Gujarat), India.
rkjana2003@yahoo.com
10.22034/kjm.2019.97090
We develop Bernstein type operators using the Beta function and study their approximation properties. By using Korovkin's theorem, we achieve the uniform convergence of sequences of these operators. We obtain the rate of convergence in terms of modulus of continuity and establish the Voronovskaja type asymptotic result for these operators. At last the graphical comparison of these newly defined operators with few of the fundamental but significant operators is discussed.
Beta function,Korovkin theorem,Modulus of continuity,Voronovskaya type result
http://www.kjmmath.org/article_97090.html
http://www.kjmmath.org/article_97090_cadb0c8d0798a9820fa3976ce509413e.pdf
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 Mathematics
24234788
6
1
2020
01
01
Invariant Submanifolds of LPSasakian Manifolds
16
26
EN
Venkatesha
Venkatesha
0000000227992535
Department of Mathematics, Kuvempu University, Shankaraghatta577451, Karnataka, India.
vensmath@gmail.com
Shanmukha
Basavarajappa
Department of Mathematics, Kuvempu University, Shankaraghatta577451, Karnataka, India.
meshanmukha@gmail.com
10.22034/kjm.2019.97091
The object of the present paper is to study some geometric conditions for an invariant submanifold of an LPSasakian manifold to be totally geodesic. Further we consider concircular curvature tensor satisfying some geometric conditions of an invariant submanifold of an LPSasakian manifold to be totally geodesic. In extension, we build an example of LPSasakian manifold to verify our main result totally geodesic.
Submanifold,LPSasakian manifold,concircular curvature tensor
http://www.kjmmath.org/article_97091.html
http://www.kjmmath.org/article_97091_d52712c3a0533f86645740d2df993eba.pdf
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 Mathematics
24234788
6
1
2020
01
01
Various Energies of Commuting Graphs of Finite Nonabelian Groups
27
45
EN
Parama
Dutta
Department of Mathematical Sciences, Tezpur University, Napaam 784028, Sonitpur, Assam, India.
parama@gonitsora.com
Biswadeep
Bagchi
Department of Mathematical Sciences, Tezpur University, Napaam 784028, Sonitpur, Assam, India.
biswadeepbagchi430@gmail.com
Rajat
Kanti
Nath
Department of Mathematical Sciences, Tezpur University, Napaam 784028, Sonitpur, Assam, India.
rajatkantinath@yahoo.com
10.22034/kjm.2019.97094
The commuting graph of a finite nonabelian group $G$ is a simple undirected graph, denoted by $Gamma_G$, whose vertex set is the noncentral elements of $G$ and two distinct vertices $x$ and $y$ are adjacent if and only if $xy = yx$. In this paper, we compute energy, Laplacian energy, and signless Laplacian energy of $Gamma_G$ for various families of finite nonabelian groups and analyze their values graphically. Our computations show that the conjecture posed in [MATCH Commun. Math. Comput. Chem. 59, (2008) 343354 ] holds for the commuting graph of some families of finite groups.
Commuting graph,spectrum,Energy,finite group
http://www.kjmmath.org/article_97094.html
http://www.kjmmath.org/article_97094_19bea7eef79e328fcdc7ad5118452748.pdf
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 Mathematics
24234788
6
1
2020
01
01
Some Properties of Prime and ZSemiIdeals in Posets
46
56
EN
Kasi
Porselvi
Department of Mathematics, Karunya Institute of Technology and Sciences,
Coimbatore  641 114, India.
porselvi94@yahoo.co.in
Balasubramanian
Elavarasan
0000000214142814
Department of Mathematics, Karunya Institute of Technology and Sciences,
Coimbatore  641 114, India.
belavarasan@gmail.com
10.22034/kjm.2019.97095
We define the notion of zsemiideals in a poset $P$ and we show that if a zsemiideal $J$ satisfies $(ast )$property, then every minimal prime semiideal containing $J$ is also a zsemiideal of $P.$ We also show that every prime semiideal is a zsemiideal or the maximal zsemiideals contained in it are prime zsemiideals. Further, we characterize some properties of union of prime semiideals of $P$ provided the prime semiideals are contained in the unique maximal semiideal of $P.$
Posets,semiideals,prime semiideals,minimal prime semiideals,msystem
http://www.kjmmath.org/article_97095.html
http://www.kjmmath.org/article_97095_c7b4d571f0807aca269c3e30f1b3b35f.pdf
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 Mathematics
24234788
6
1
2020
01
01
Strongly Quasilinear Parabolic Systems in Divergence Form with Weak Monotonicity
57
72
EN
Elhoussine
Azroul
Department of Mathematics, Faculty of Sciences Dhar El Mehraz, B.P. 1796 Atlas, FezMorocco.
elhoussine.azroul@gmail.com
Farah
Balaadich
Department of Mathematics, Faculty of Sciences Dhar El Mehraz, B.P. 1796 Atlas, FezMorocco.
balaadich.edp@gmail.com
10.22034/kjm.2019.97170
The existence of solutions to the strongly quasilinear parabolic system<br />[frac{partial u}{partial t}text{div},sigma(x,t,u,Du)+g(x,t,u,Du)=f,]<br />is proved, where the source term $f$ is assumed to belong to $L^{p'}(0,T; W^{1,p'}(Omega;R^m))$. Further, we prove the existence of a weak solution by means of the Young measures under mild monotonicity assumptions on $sigma$.
Quasilinear parabolic systems,weak monotonicity,weak solution,Young measures
http://www.kjmmath.org/article_97170.html
http://www.kjmmath.org/article_97170_c50bb41e07dca9346043d4702bb0d0b2.pdf
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 Mathematics
24234788
6
1
2020
01
01
On Approximation of Functions Belonging to some Classes of Functions by $(N,p_n,q_n)(E,theta )$ Means of Conjugate Series of Its Fourier Series
73
86
EN
Xhevat
Zahir
Krasniqi
University of Prishtina "Hasan Prishtina", Faculty of Education, Department of Mathematics and Informatics, Avenue "Mother Theresa" 5, 10000 Prishtina, Kosovo.
xhevat.krasniqi@unipr.edu
Deepmala

Mathematics Discipline, PDPM Indian Institute of Information Technology,
Design and Manufacturing, Jabalpur, Dumna Airport Road, P.O.: Khamaria,
Jabalpur 482 005, Madhya Pradesh, India.
dmrai23@gmail.com
10.22034/kjm.2019.97173
We obtain some new results on the approximation of functions belonging to some classes of functions by $(N,p_n,q_n)(E,theta )$ means of conjugate series of its Fourier series. These results, under conditions assumed here, are better than those obtained previously by others. In addition, several particular results are derived from our results as corollaries.
Fourier series,generalized N"{o}rlund means,conjugate Fourier series,degree of approximation
http://www.kjmmath.org/article_97173.html
http://www.kjmmath.org/article_97173_e5cbb8cc4f0476c8532b33b6a744e7ab.pdf
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 Mathematics
24234788
6
1
2020
01
01
On Pair of Generalized Derivations in Rings
87
94
EN
Asma
Ali
Department of Mathematics, Aligarh Muslim University, Aligarh202002,
India.
asma_ali2@rediffmail.com
Md
Hamidur
Rahaman
Department of Mathematics, Aligarh Muslim University, Aligarh202002,
India.
rahamanhamidmath@gmail.com
10.22034/kjm.2019.97174
Let $R$ be an associative ring with extended centroid $C$, let $G$ and $F$ be generalized derivations of $R$ associated with nonzero derivations $delta$ and $d$, respectively, and let $m, k, n geq1$ be fixed integers. In the present paper, we study the situations: (i)$F(x)circ_{m}G(y)=(x circ_{n} y)^{k}$, (ii) $[F(x),y]_{m}+[x,d(y)]_{n}=0$ for all $y, x$ in some appropriate subset of $R$.
Prime rings,semiprime rings,generalized derivations,extended centroid
http://www.kjmmath.org/article_97174.html
http://www.kjmmath.org/article_97174_d6600441ebda02c760dafc2171b8c9a6.pdf
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 Mathematics
24234788
6
1
2020
01
01
Approximating Solutions of ThirdOrder Nonlinear Hybrid Differential Equations via Dhage Iteration Principle
95
103
EN
Abdelouaheb
Ardjouni
Faculty of Sciences and Technology, Department of Mathematics and Informatics, Souk Ahras University, P.O. Box 1553, Souk Ahras, 41000, Algeria.
abd_ardjouni@yahoo.fr
Ahcene
Djoudi
Applied Mathematics Lab, Faculty of Sciences, Department of Mathematics,
Annaba University, P.O. Box 12, Annaba, 23000, Algeria.
adjoudi@yahoo.com
10.22034/kjm.2019.97175
We prove the existence and approximation of solutions of the initial value problems of nonlinear thirdorder hybrid differential equations. The main tool employed here is the Dhage iteration principle in a partially ordered normed linear space. An example is also given to illustrate the main results.
Approximating solutions,Initial value problems,Dhage iteration principle,hybrid fixed point theorem
http://www.kjmmath.org/article_97175.html
http://www.kjmmath.org/article_97175_4f0895cb4388259d8103049f6f6095a4.pdf
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 Mathematics
24234788
6
1
2020
01
01
On the Norm of Jordan $*$Derivations
104
107
EN
Abolfazl
Niazi Motlagh
Department of Mathematics, Faculty of basic sciences, University of Bojnord,
P.O. Box 1339, Bojnord, Iran.
niazimotlagh@gmail.com
10.22034/kjm.2019.97176
Let $mathcal H$ be a complex Hilbert space and let $B(mathcal H)$ be the algebra of all bounded linear operators on $mathcal H$. Let $Tin B(mathcal H)$.<br />In this paper, we determine the norm of the inner Jordan $*$derivation $Delta_T:Xmapsto TXX^*T$ acting on the Banach algebra $B(mathcal{H})$. More precisely, we show that $$big{}Delta_Tbig{}geq 2sup_{lambdain W_0(T)}{rm Im}(lambda)$$<br />in which $W_0(T)$ is the maximal numerical range of operator $T$.
Jordan$*$derivation,Numerical Range,maximal numerical range
http://www.kjmmath.org/article_97176.html
http://www.kjmmath.org/article_97176_b3a4d842feb70c384bb0001e22fc2e2b.pdf
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 Mathematics
24234788
6
1
2020
01
01
Commuting Conjugacy Class Graph of Finite CAGroups
108
118
EN
Mohammad
Ali
Salahshour
Department of Pure Mathematics, University of Kashan, Kashan 8731753153, Iran.
salahshour@iausk.ac.ir
Ali
Reza
Ashrafi
Department of Pure Mathematics, University of Kashan, Kashan 8731753153, Iran.
ashrafi_1385@yahoo.co.in
10.22034/kjm.2019.97177
Let $G$ be a finite nonabelian group. The commuting conjugacy class graph $Gamma(G)$ is a simple graph with the noncentral conjugacy classes of $G$ as its vertex set and two distinct vertices $X$ and $Y$ in $Gamma(G)$ are adjacent if and only if there are $x in X$ and $y in Y$ with this property that $xy = yx$. The aim of this paper is to obtain the structure of the commuting conjugacy class graph of finite CAgroups. It is proved that this graph is a union of some complete graphs. The commuting conjugacy class graph of certain groups are also computed.
Commuting conjugacy class graph,Commuting graph,CAgroup,quotient graph
http://www.kjmmath.org/article_97177.html
http://www.kjmmath.org/article_97177_3bc76fe226764a53f2b1071b15cca234.pdf
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 Mathematics
24234788
6
1
2020
01
01
On Jensen's Multiplicative Inequality for Positive Convex Functions of Selfadjoint Operators in Hilbert Spaces
119
128
EN
Silvestru
Sever
Dragomir
0000000329026805
Mathematics, College of Engineering & Science, Victoria University, PO
Box 14428, Melbourne City, MC 8001, Australia.
sever.dragomir@vu.edu.au
10.22034/kjm.2019.97183
We obtain some multiplicative refinements and reverses of Jensen's inequality for positive convex/concave functions of selfadjoint operators in Hilbert spaces. Natural applications for power and exponential functions are provided.
Young's Inequality,Convex functions,Jensen's inequality,Selfadjoint operator,functions of selfadjoint operators
http://www.kjmmath.org/article_97183.html
http://www.kjmmath.org/article_97183_0bab1e1807c57ade01a6dbcdeaa87638.pdf
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 Mathematics
24234788
6
1
2020
01
01
On Gluing of QuasiPseudometric Spaces
129
140
EN
Yolanda
Mutemwa
School of Mathematical Sciences, NorthWest University (Mafikeng Campus), Private Bag X2046, Mmabatho 2735, South Africa.
yolanda.mutemwa@gmail.com
Olivier
Olela
Otafudu
0000000195937899
School of Mathematics, University of the Witwatersrand Johannesburg
2050, South Africa.
olivier.olelaotafudu@wits.ac.za
Hope
Sabao
0000000286495635
School of Mathematics, University of the Witwatersrand Johannesburg
2050, South Africa.
hope.sabao@wits.ac.za
10.22034/kjm.2019.97193
The concept of gluing a family of $T_0$quasimetric spaces along subsets was introduced by Otafudu. In this article, we continue the study of externally Isbellconvex and weakly externally Isbellconvex subsets of a $T_0$quasimetric space. We finally investigate some properties of the resulting $T_0$quasimetric space obtained by gluing a family of Isbellconvex $T_0$quasimetric spaces attached<br />along isometric subspaces.
Isbellconvexity,gluing quasipseudometric,externally Isbellconvexity
http://www.kjmmath.org/article_97193.html
http://www.kjmmath.org/article_97193_f40ec285c7f66495a0dc6501643590b4.pdf