ORIGINAL_ARTICLE
Differences of operators of generalized Szász type
We derive the approximation of differences of operators. Firstly, we study quantitative estimates for the difference of generalized Szász operators with generalized Szász-Durrmeyer, Szász-Puãltvänea operators, and generalized Szász--Kantorovich operators. Finally, we obtain the quantitative estimate in terms of the weighted modulus of smoothness for these operators.
http://www.kjm-math.org/article_109811_063527dcdf3c26b57d02e2a97cd9e179.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
141
154
10.22034/kjm.2020.109811
Positive approximation process
Szasz operators
Pualtvanea operators
Arun
Kajla
rachitkajla47@gmail.com
true
1
Department of mathematics, Central University of Haryana, Haryana-123031, India.
Department of mathematics, Central University of Haryana, Haryana-123031, India.
Department of mathematics, Central University of Haryana, Haryana-123031, India.
LEAD_AUTHOR
Ruchi
Gupta
ruchigupta@mru.edu.in
true
2
Department of Mathematics, Manav Rachna University, Faridabad-121004, Haryana, India
Department of Mathematics, Manav Rachna University, Faridabad-121004, Haryana, India
Department of Mathematics, Manav Rachna University, Faridabad-121004, Haryana, India
AUTHOR
ORIGINAL_ARTICLE
Admissible inertial manifolds for second order in time evolution equations
We prove the existence of admissible inertial manifolds for the second order in time evolution equations of the form $$ \ddot{x}+2\varepsilon \dot{x}+Ax=f(t,x)$$ when $A$ is positive definite and self-adjoint with a discrete spectrum and the nonlinear term $f$ satisfies the $\varphi$-Lipschitz condition, that is, $\|f(t,x)-f(t,y)\|\leqslant\varphi(t)\left \|A^{\beta}(x-y)\right \|$ for $\varphi$ belonging to one of the admissible Banach function spaces containing wide classes of function spaces like $L_{p}$-spaces, the Lorentz spaces $L_{p,q}$, and many other function spaces occurring in interpolation theory.
http://www.kjm-math.org/article_109813_372333a09954785108dc346740036a94.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
155
173
10.22034/kjm.2020.109813
Admissible inertial manifolds
second order in time evolution equations
admissible function spaces
Lyapunov--Perron method
Anh
Le
leanhminh@hdu.edu.vn
true
1
Department of Mathematical Analysis, Faculty of Natural Sciences, Hongduc University, Thanh Hoa, Vietnam
Department of Mathematical Analysis, Faculty of Natural Sciences, Hongduc University, Thanh Hoa, Vietnam
Department of Mathematical Analysis, Faculty of Natural Sciences, Hongduc University, Thanh Hoa, Vietnam
LEAD_AUTHOR
ORIGINAL_ARTICLE
$n$-Absorbing $I$-ideals
Let $R$ be a commutative ring with identity, let $ I $ be a proper ideal of $ R $, and let $ n \ge 1 $ be a positive integer. In this paper, we introduce a class of ideals that is closely related to the class of $I$-prime ideals. A proper ideal $P$ of $R$ is called an {\itshape $n$-absorbing $I$-ideal} if $a_1,\ a_2,\ \dots ,\ a_{n+1} \in R$ with $a_1 a_2 \dots a_{n+1} \in P-IP$, then $a_1 a_2 \dots a_{i-1} a_{i+1} \dots a_{n+1} \in P$ for some $i\in \left\{1,\ 2,\ \dots ,\ {n+1} \right\}$. Among many results, we show that every proper ideal of a ring $R$ is an {\itshape $n$-absorbing $I$-ideal} if and only if every quotient of $ R$ is a product of $(n+1)$-fields.
http://www.kjm-math.org/article_109814_41bf620131018d2506a78fe17acb8a4a.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
174
179
10.22034/kjm.2020.109814
$2$-absorbing ideal
$n$-absorbing ideal
$I$-prime ideal
Prime ideal
$n$-absorbing $I$-ideal
Ismael
Akray
ismaeelhmd@yahoo.com
true
1
Department of Mathematics, University of Soran, Erbil city, Kurdistan region, Iraq.
Department of Mathematics, University of Soran, Erbil city, Kurdistan region, Iraq.
Department of Mathematics, University of Soran, Erbil city, Kurdistan region, Iraq.
LEAD_AUTHOR
Mediya
Mrakhan
medya.bawaxan@garmian.edu.krd
true
2
Department of Mathematics, University of Garmian, Kalar city, Kurdistan region, Iraq.
Department of Mathematics, University of Garmian, Kalar city, Kurdistan region, Iraq.
Department of Mathematics, University of Garmian, Kalar city, Kurdistan region, Iraq.
AUTHOR
ORIGINAL_ARTICLE
Some classes of Probabilistic Inner product spaces and related inequalities
We give a new definition for probabilistic inner product spaces, which is sufficiently general to encompass the most important class of probabilistic inner product spaces (briefly, PIP spaces). We have established certain classes of PIP spaces and especially, illustrated that how to construct a real inner product from a Menger PIP space. Finally, we have established the analogous of Cauchy--Schwarz inequality in this general PIP spaces.
http://www.kjm-math.org/article_109815_64d0951ded0a74c231310779685b3daa.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
180
192
10.22034/kjm.2020.109815
Probabilistic normed spaces
$t$-norm
$t$-conorm
Panackal
Harikrishnan
pkharikrishnans@gmail.com
true
1
Department of Mathematics, Manipal institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, India.
Department of Mathematics, Manipal institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, India.
Department of Mathematics, Manipal institute of Technology, Manipal Academy of Higher Education, Manipal, Karnataka, India.
LEAD_AUTHOR
Bernardo
Lafuerza Guillen
blafuerza@gmail.com
true
2
Departamento de Estadistica y Matematica Aplicada, Universidad de Almeria, 04120 Almeria, Spain.
Departamento de Estadistica y Matematica Aplicada, Universidad de Almeria, 04120 Almeria, Spain.
Departamento de Estadistica y Matematica Aplicada, Universidad de Almeria, 04120 Almeria, Spain.
AUTHOR
ORIGINAL_ARTICLE
On the Arens regularity of a module action and its extensions
It is known that if the second dual $A^{**}$ of a Banach algebra $A$ is Arens regular, then $A$ is Arens regular itself. However, the converse is not true, in general. Young gave an example of an Arens regular Banach algebra whose second dual is not Arens regular. Later Pym has polished Young's example for presenting more applicable examples. In this paper, we mimic the methods of Young and Pym to present examples of some Arens regular bilinear maps and module actions whose some extensions are not Arens regular. Finally, some relationships between the topological centers of certain Banach module actions are investigated.
http://www.kjm-math.org/article_109816_130168186224906cc95a0197cf770c0e.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
193
198
10.22034/kjm.2020.109816
Bilinear map
Banach algebra
module action
Arens regular
Sedighe
Barootkoob
s.barutkub@ub.ac.ir
true
1
Department of Mathematics, University of Bojnord, P.O. Box 1339, Bojnord, Iran.
Department of Mathematics, University of Bojnord, P.O. Box 1339, Bojnord, Iran.
Department of Mathematics, University of Bojnord, P.O. Box 1339, Bojnord, Iran.
LEAD_AUTHOR
ORIGINAL_ARTICLE
Distinguishing number (index) and domination number of a graph
The distinguishing number (index) of a graph $G$ is the least integer $d$ such that $G$ has a vertex labeling (edge labeling) with $d$ labels that is preserved only by the trivial automorphism. A set $S$ of vertices in $G$ is a dominating set of $G$ if every vertex of $V(G)\setminus S$ is adjacent to some vertex in $S$. The minimum cardinality of a dominating set of $G$ is the domination number of $G$. In this paper, we obtain some upper bounds for the distinguishing number and the distinguishing index of a graph based on its domination number.
http://www.kjm-math.org/article_109817_a3bf156522e2b7558c7dc5148bbbdf86.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
199
205
10.22034/kjm.2020.109817
distinguishing number
Distinguishing index
Domination number
Saeid
Alikhani
alikhani@yazd.ac.ir
true
1
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran
LEAD_AUTHOR
Samaneh
Soltani
s.soltani1979@gmail.com
true
2
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran
Department of Mathematics, Yazd University, 89195-741, Yazd, Iran
AUTHOR
ORIGINAL_ARTICLE
Strong rainbow coloring of unicyclic graphs
A path in an edge-colored graph is called a \textit{rainbow path}, if no two edges of the path are colored the same. An edge-colored graph $G$, is \textit{rainbow-connected} if any two vertices are connected by a rainbow path. A rainbow-connected graph is called strongly rainbow connected if for every two distinct vertices $u$ and $v$ of $V(G)$, there exists a rainbow path $P$ from $u$ to $v$ that in the length of $P$ is equal to $d(u,v)$. The notations {\rm rc}$(G)$ and {\rm src}$(G)$ are the smallest number of colors that are needed in order to make $G$ rainbow connected and strongly rainbow connected, respectively. In this paper, we find the exact value of {\rm rc}$(G)$, where $G$ is a unicyclic graph. Moreover, we determine the upper and lower bounds for {\rm src}$(G)$, where $G$ is a unicyclic graph, and we show that these bounds are sharp.
http://www.kjm-math.org/article_109818_301fa61eefbf5cce342037ce7790283b.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
206
216
10.22034/kjm.2020.109818
Rainbow connection number
strong rainbow connection number
unicyclic graph
Amin
Rostami
ramin6613@gmail.com
true
1
Department of Pure Mathematics, Ferdowsi University of Mashhad, P.O. Box 1159, Mashhad 91775, Iran
Department of Pure Mathematics, Ferdowsi University of Mashhad, P.O. Box 1159, Mashhad 91775, Iran
Department of Pure Mathematics, Ferdowsi University of Mashhad, P.O. Box 1159, Mashhad 91775, Iran
AUTHOR
Madjid
Mirzavaziri
mirzavaziri@um.ac.ir
true
2
Department of Pure Mathematics, Ferdowsi University of Mashhad, P.O. Box 1159, Mashhad 91775, Iran
Department of Pure Mathematics, Ferdowsi University of Mashhad, P.O. Box 1159, Mashhad 91775, Iran
Department of Pure Mathematics, Ferdowsi University of Mashhad, P.O. Box 1159, Mashhad 91775, Iran
LEAD_AUTHOR
Freydoon
Rahbarnia
rahbarnia@um.ac.ir
true
3
Department of Applied Mathematics, Ferdowsi University of Mashhad, P.O. Box 1159, Mashhad 91775, Iran.
Department of Applied Mathematics, Ferdowsi University of Mashhad, P.O. Box 1159, Mashhad 91775, Iran.
Department of Applied Mathematics, Ferdowsi University of Mashhad, P.O. Box 1159, Mashhad 91775, Iran.
AUTHOR
ORIGINAL_ARTICLE
Stability result of the Bresse system with delay and boundary feedback
Our interest in this paper is to analyze the asymptotic behavior of a Bresse system together with three boundary controls, with delay terms in the first, second, and third equations. By using the semigroup method, we prove the global well-posedness of solutions. Assuming the weights of the delay are small, we establish the exponential decay of energy to the system by using an appropriate Lyapunov functional.
http://www.kjm-math.org/article_109819_a6fe24f2fbf18095d111f0f18897fdc8.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
217
235
10.22034/kjm.2020.109819
Bresse system
delay
global solutions
Stability
damping
exponential decay
Hocine
Makheloufi
hocine.makheloufi@univ-mascara.dz
true
1
University of Mascara Mustapha Stambouli, Faculty of Exact Sciences, Department of Mathematics, P.O. Box 305, Mascara 29000, Algeria.
University of Mascara Mustapha Stambouli, Faculty of Exact Sciences, Department of Mathematics, P.O. Box 305, Mascara 29000, Algeria.
University of Mascara Mustapha Stambouli, Faculty of Exact Sciences, Department of Mathematics, P.O. Box 305, Mascara 29000, Algeria.
AUTHOR
Mounir
Bahlil
mounir.bahlil@univ-mascara.dz
true
2
University of Mascara Mustapha Stambouli, Faculty of Exact Sciences, Department of Mathematics, P.O. Box 305, Mascara 29000, Algeria.
University of Mascara Mustapha Stambouli, Faculty of Exact Sciences, Department of Mathematics, P.O. Box 305, Mascara 29000, Algeria.
University of Mascara Mustapha Stambouli, Faculty of Exact Sciences, Department of Mathematics, P.O. Box 305, Mascara 29000, Algeria.
AUTHOR
Abbes
Benaissa
benaissa-abbes@yahoo.com
true
3
Laboratory of Analysis and Control of Partial Differential Equations, Djillali Liabes University, P. O. Box 89, Sidi Bel Abbes 22000, Algeria
Laboratory of Analysis and Control of Partial Differential Equations, Djillali Liabes University, P. O. Box 89, Sidi Bel Abbes 22000, Algeria
Laboratory of Analysis and Control of Partial Differential Equations, Djillali Liabes University, P. O. Box 89, Sidi Bel Abbes 22000, Algeria
LEAD_AUTHOR
ORIGINAL_ARTICLE
Anderson's theorem for some class of operators
Anderson's theorem states that if the numerical range of an $n\times n$ matrix is contained in the closed unit disk and intersects with the unit circle at more than $n$ points, then the numerical range coincides with the closed unit disk. In an infinite-dimensional setting, an analogue of this result for a compact operator was established by Gau and Wu and for operator being the sum of a normal and compact operator by Birbonshi et al. We consider here three classes of operators: Operators being the sum of compact and operator with numerical radius strictly less than 1, operators with essentially numerical range coinciding with the convex hull of its essential spectrum, and quasicompact operators.
http://www.kjm-math.org/article_109820_543970f9d472b56b147308cd0dc9ecaf.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
236
242
10.22034/kjm.2020.109820
Numerical Range
essentially numerical range
essentially normal operator
hyponormal operator
quasicompact operator
Mehdi
Naimi
mehdi.naimi@univ-mosta.dz
true
1
Department of Systems Engineering, National Polytechnic School of Oran-Maurice Audin (Ex. ENSET of Oran), BP 1523 Oran-El M'naouar, 31000 Oran, Algeria.
Department of Systems Engineering, National Polytechnic School of Oran-Maurice Audin (Ex. ENSET of Oran), BP 1523 Oran-El M'naouar, 31000 Oran, Algeria.
Department of Systems Engineering, National Polytechnic School of Oran-Maurice Audin (Ex. ENSET of Oran), BP 1523 Oran-El M'naouar, 31000 Oran, Algeria.
AUTHOR
Mohammed
Benharrat
mohammed.benharrat@gmail.com
true
2
Department of Systems Engineering, National Polytechnic School of Oran-Maurice Audin (Ex. ENSET of Oran), BP 1523 Oran-El M'naouar, 31000 Oran, Algeria.
Department of Systems Engineering, National Polytechnic School of Oran-Maurice Audin (Ex. ENSET of Oran), BP 1523 Oran-El M'naouar, 31000 Oran, Algeria.
Department of Systems Engineering, National Polytechnic School of Oran-Maurice Audin (Ex. ENSET of Oran), BP 1523 Oran-El M'naouar, 31000 Oran, Algeria.
LEAD_AUTHOR
ORIGINAL_ARTICLE
Radically principal rings
Let $A$ be a commutative ring. An ideal $I$ of $A$ is radically principal if there exists a principal ideal $J$ of $A$ such that $\sqrt{I}=\sqrt{J}$. The ring $A$ is radically principal if every ideal of $A$ is radically principal. In this article, we study radically principal rings. We prove an analogue of the Cohen theorem, precisely, a ring is radically principal if and only if every prime ideal is radically principal. Also we characterize a zero-dimensional radically principal ring. Finally we give a characterization of polynomial ring to be radically principal.
http://www.kjm-math.org/article_109821_13bebfe55715bbb4a8fec12a006e6f52.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
243
249
10.22034/kjm.2020.109821
radical
radically principal
polynomial ring
Mohamed
Aqalmoun
maqalmoun@yahoo.fr
true
1
Sidi Mohamed Ben Abdellah University, Higher Normal school, Fez,
Sidi Mohamed Ben Abdellah University, Higher Normal school, Fez,
Sidi Mohamed Ben Abdellah University, Higher Normal school, Fez,
LEAD_AUTHOR
Mounir
Ouarrachi
m.elouarrachi@gmail.com
true
2
Department of Mathematics, Faculty of Sciences and technologies, University Sidi Mohamed Ben Abdallah Fes, Morocco.
Department of Mathematics, Faculty of Sciences and technologies, University Sidi Mohamed Ben Abdallah Fes, Morocco.
Department of Mathematics, Faculty of Sciences and technologies, University Sidi Mohamed Ben Abdallah Fes, Morocco.
AUTHOR
ORIGINAL_ARTICLE
Embedding topological spaces in a type of generalized topological spaces
A stack on a nonempty set $X$ is a collection of nonempty subsets of $X$ that is closed under the operation of superset. Let $(X, \tau)$ be an arbitrary topological space with a stack $\mathcal{S}$, and let $X^*=X \cup \{p\}$ for $p \notin X$. In the present paper, using the stack $\mathcal{S}$ and the topological closure operator associated to the space $(X, \tau)$, we define an envelope operator on $X^*$ to construct a generalized topology $\mu_\mathcal{S}$ on $X^*$. We then show that the space $(X^*, \mu_\mathcal{S})$ is the generalized extension of the space $(X, \tau)$. We also provide conditions under which $(X^*, \mu_\mathcal{S})$ becomes a generalized Hausdorff space.
http://www.kjm-math.org/article_109822_48153543d90491ae26ff4e6f0859818e.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
250
256
10.22034/kjm.2020.109822
Generalized topology
generalized extension
one-point generalized extension
strong generalized topology
Stack
Amin
Talabeigi
talabeigi.amin@gmail.com
true
1
Department of Mathematics, Payame Noor University, P.O. Box, 19395-3697, Tehran, Iran.
Department of Mathematics, Payame Noor University, P.O. Box, 19395-3697, Tehran, Iran.
Department of Mathematics, Payame Noor University, P.O. Box, 19395-3697, Tehran, Iran.
LEAD_AUTHOR
ORIGINAL_ARTICLE
Approximation for the Bernstein operator of max-product kind in symmetric range
In the approximation theory, polynomials are particularly positive linear operators. Nonlinear positive operators by means of maximum and product were introduced by B. Bede. In this paper, the max-product of Bernstein operators for symmetric ranges are introduced and some upper estimates of approximation error for some subclasses of functions are obtained. Also, we investigate the shape-preserving properties.
http://www.kjm-math.org/article_109823_a7fe73d3f8242f905b067eb48196f51c.pdf
2020-07-01T11:23:20
2021-04-11T11:23:20
257
273
10.22034/kjm.2020.109823
Max-product
degree of approximation
symmetric range
shape-preserving properties
Ecem
Acar
karakusecem@harran.edu.tr
true
1
Department of Mathematics, University of Harran, 63100, Anlurfa, Turkey
Department of Mathematics, University of Harran, 63100, Anlurfa, Turkey
Department of Mathematics, University of Harran, 63100, Anlurfa, Turkey
LEAD_AUTHOR
Done
Karahan
dkarahan@harran.edu.tr
true
2
Department of Mathematics, University of Harran, 63100, Anlurfa, Turkey
Department of Mathematics, University of Harran, 63100, Anlurfa, Turkey
Department of Mathematics, University of Harran, 63100, Anlurfa, Turkey
AUTHOR
Sevilay
Kirci Serenbay
sevilaykirci@gmail.com
true
3
Department of Mathematics, University of Harran, 63100, Anlurfa, Turkey.
Department of Mathematics, University of Harran, 63100, Anlurfa, Turkey.
Department of Mathematics, University of Harran, 63100, Anlurfa, Turkey.
AUTHOR