2021
2
1
0
115
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On the rank of the holomorphic solutions of PDE associated to directed graphs
https://ajmc.aut.ac.ir/article_4121.html
10.22060/ajmc.2020.18413.1031
1
Let G be a directed graph with m vertices and n edges, I(B) thebinomial ideal associated to the incidence matrix B of the graph G, and I_L the latticeideal associated to the columns of the matrix B. Also let B_i be a submatrix ofB after removing the ith column. In this paper it is determined that which primeminimal ideals of I(B_i) are Andean or toral. Then we study the rank of the spaceof solutions of binomial Dmodule associated to I(B_i) as Agraded ideal, where A isa matrix that, AB_i = 0. Afterwards, we define a maximal cellular cycle and provethat for computing this rank it is enough to consider these components of G. Weintroduce some bounds for the number of the vertices of the convex hull generatedby the columns of the matrix A. Finally an algorthim is introduced by which we cancompute the volume of the convex hull corresponded to a cycles with k diagonals, soby Theorem 2.1 the rank of (D / H_A(I(B_i); beta)) can be computed.
0

1
9


Hamid
Damadi
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
hamid.damadi@aut.ac.ir


Farhad
Rahmati
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
frahmati@aut.ac.ir
Directed graph
Binomial Dmodule
Lattice basis ideal
1

Recognition by degree primepower graph and order of some characteristically simple group
https://ajmc.aut.ac.ir/article_4122.html
10.22060/ajmc.2020.18418.1033
1
In this paper, by the order of a group and triviality of $O_p(G)$ for some prime $p$, we give a new characterization for some characteristically simple groups. In fact, we prove that if pϵ{5, 17, 23, 37, 47, 73} and n≤p, where $n$ is a natural number, then $Gcong{{rm PSL}(2,p)}^{n}$ if and only if $ G={{rm PSL}(2,p)}^{n}$ and $ O_p(G)=1$.}Recently in [Qin, Yan, Shum and Chen, Comm. Algebra, 2019], the degree primepower graph of a finite group have been introduced and it is proved that the Mathieu groups are uniquely determined by their degree primepower graphs and orders. As a consequence of our results, we show that ${rm PSL}(2,p)^n$, where pϵ{5,17,23,37,47,73} and n≤p are uniquely determined by their degree primepower graphs and orders.
0

11
15


Afsane
Bahri
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
afsanebahri@aut.ac.ir


Behrooz
Khosravi
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic)
Iran
bkhosravi@aut.ac.ir


Morteza
Baniasad Azad
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic)
Iran
baniasad84@gmail.com
Degree prime power graph
order
characteristically simple group
Characterization
1

A class of operator related weighted composition operators between Zygmund space
https://ajmc.aut.ac.ir/article_4132.html
10.22060/ajmc.2020.18833.1041
1
Let $mathbb {D}$ be the open unit disk in the complex plane $mathbb{C}$ and $H(mathbb{D})$ be the set of all analytic functions on $mathbb{D}$. Let $u, vin H(mathbb{D})$ and $varphi$ be an analytic selfmap of $mathbb{D}$. A class of operatorrelated weighted composition operatorsis defined as followbegin{align*}T_{u, v, varphi}f(z) = u(z) f{(varphi(z))}+ v(z) f'(varphi(z)) ,quad fin H(mathbb{D} ), quad zin mathbb{D}.end{align*}In this work, we obtain some new characterizations for boundedness and essential norm of operator $T_{u, v, varphi}$ between Zygmund space.
0

17
25


Ebrahim
Abbasi
Department of Mathematics&lrm;, &lrm;Mahabad Branch&lrm;, &lrm;Islamic Azad University&lrm;, &lrm;Mahabad&lrm;, &lrm;Iran
Iran
ebrahimabbasi81@gmail.com
boundedness
compactness
essential norm
Zygmund space
1

On GDWRanders metrics on tangent Lie groups
https://ajmc.aut.ac.ir/article_4160.html
10.22060/ajmc.2020.18572.1038
1
Let $G$ be a Lie group equipped with a leftinvariant Randers metric $F$. Suppose that $F^v$ and $F^c$ denote the vertical and complete lift of $F$ on $TG$, respectively. We give the necessary and sufficient conditions under which $F^v$ and $F^c$ are generalized DouglasWeyl metrics. Then, we characterize all 2step nilpotent Lie groups $G$ such that their tangent Lie groups $(TG, F^c)$ are generalized DouglasWeyl Randers metrics.
0

27
36


Mona
Atashafrouz
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
m.atashafrooz@aut.ac.ir


Behzad
Najafi
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
behzad.najafi@aut.ac.ir


Akbar
Tayebi
Department of Mathematics, Faculty of Science, University of Qom, Qom, Iran
Iran
akbar.tayebi@gmail.com
Leftinvariant metric
Douglas metric
Generalized DouglasWeyl Metrics
1

Conservation law and Lie symmetry analysis of foam drainage equation
https://ajmc.aut.ac.ir/article_4161.html
10.22060/ajmc.2020.18460.1036
1
In this paper, using the Lie group analysis method, we study the group invariant of the Foam Drainage equation. It shows that this equation can be reduced to ODE. Also we apply the Liegroup classical, and the nonclassical method due to Bluman and Cole to deduce symmetries of the Foam Drainage equation. and we prove that the nonclassical method applied to the equation leads to new reductions, which cannot be obtained by Lie classical symmetries. Also this paper shows how to construct directly the local conservation laws for this equation
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37
44


Mehdi
Nadjafikhah
School of Mathematics, Iran University of Science and Technology
Iran
m_nadjafikhah@iust.ac.ir


Omid
Chekini
School of Mathematics, Iran University of Science and Technology
Iran
omid_chgini@mathdep.iust.ac.ir
Lie group analysis
Conservation law
Optimal system
Foam Drainage equation
1

An extension of the Cardioid distributions on circle
https://ajmc.aut.ac.ir/article_4209.html
10.22060/ajmc.2020.18285.1029
1
A new family of distributions on the circle is introduced which is a generalization of the Cardioid distributions. The elementary properties such as mean, variance, and the characteristic function are computed. The distribution is shown to be either unimodal or bimodal. The modes are computed. The symmetry of the distribution is characterized. The parameters are shown to be canonic (i.e. uniquely determined by the distribution). This implies that the estimation problem is welldefined. We also show that this new family is a subset of distributions whose Fourier series has degree at most 2 and study the implications of this property. Finally, we study the maximum likelihood estimation for this family.
0

45
52


Erfan
Salavati
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
erfan.salavati@aut.ac.ir
Circular Distributions
Cardioid Distribution
Von Mises Distribution
1

Estimation of the parameter of Levy distribution using ranked set sampling
https://ajmc.aut.ac.ir/article_4216.html
10.22060/ajmc.2020.18499.1037
1
Ranked set sampling is a statistical technique for data collection that generallyleads to more efficient estimators than competitors based on simple random sampling.In this paper, we consider estimation of scale parameter of Levy distribution using a ranked set sample. We derive the best linear unbiased estimatorand its variance, based on a ranked set sample. Also we compare numerically, variance of this estimator with mean square error of the maximum likelihood, a median based estimator and an estimator based on Laplace transform. It turns out that the best linear unbiased estimator based on ranked set sampling is more efficient than other mentioned estimators.
0

53
60


Sahar
Dorniani
Department of Statistics, Roudehen
Branch, Islamic Azad University, Tehran, Iran
Iran
sdorniani@yahoo.com


Adel
Mohammadpour
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
adelmohammadpour1@gmail.com


Nader
Nematollahi
Department of Statistics, Allameh Tabataba'i
University, Tehran, Iran.
Iran
na_nemat@yahoo.com
Best linear unbiased estimator
Levy distribution
Ranked set sampling
Scale parameter
1

Some conformal vector fields and conformal Ricci solitons on N(k)contact metric manifolds
https://ajmc.aut.ac.ir/article_4246.html
10.22060/ajmc.2021.19220.1043
1
Abstract. The target of this paper is to study N(k)contact metric manifoldswith some types of conformal vector fields like φholomorphic planar conformalvector fields and Ricci biconformal vector fields. We also characterize N(k)contact metric manifolds allowing conformal Ricci almost soliton. Obtained results are supported by examples.
0

61
71


Uday
De
Department of Pure Mathematics, Faculty of Science, University of Calcutta, Kolkata, India
India
uc_de@yahoo.com


Arpan
Sardar
Department of Mathematics, Faculty of Science, University of Kalyani, West Bengal, India
India
arpansardar51@gmail.com


Avijit
Sarkar
Department of Mathematics, Faculty of Science, University of Kalyani, West Bengal
India
avjaj@yahoo.co.in
N(k)contact metric manifolds
φholomorphic planar conformal vector fields
conformal vector fields and conformal Ricci solitons
1

On the reversible geodesics of a Finsler space endowed with a special deformed (α,β)metric
https://ajmc.aut.ac.ir/article_4270.html
10.22060/ajmc.2021.19522.1048
1
The scope of this paper is twofold. On the one hand, we will investigate the reversible geodesics of a Finsler space endowed with the deformed newly introduced (α,β)metric begin{equation}F_{ε}(α,β)=frac{β^{2}+α^{2}(a+1)}{α}+εβend{equation}where ε is a real parameter with ε<2√a+1 and ain(¼,∞); and on the other hand, we will investigate the Ttensor for this metric.
0

73
80


LaurianIoan
Pişcoran
Department of Mathematics and Computer Science, Victoriei 76, 430122 Baia Mare, Romania
Romania
plaurian@yahoo.com


Ali
Akram
Departamento de MatematicaICE, Universidade Federal de AmazonasUFAM, 69080900 Manaus
Brazil
akramali@ufam.edu.br


Cătălin
Barbu
"Vasile Alecsandri" National College, str. Vasile Alecsandri nr. 37, Bacau, Romania
Romania
kafka_mate@yahoo.com
Finsler (α,β)metric
deformation of an (α,β)metric
Ttensor
1

Ensuring software maintainability at software architecture level using architectural patterns
https://ajmc.aut.ac.ir/article_4272.html
10.22060/ajmc.2021.19232.1044
1
Software architecture is known to be an effective tool with regards to improving software quality attributes. Many quality attributes such as maintainability are architecture dependent, and as such, using an appropriate architecture is essential in providing a sound foundation for the development of highly maintainable software systems. An effective way to produce a wellbuilt architecture is to utilize standard architectural patterns.Although the use of a particular architectural pattern cannot have a preserving effect on software maintainability, the mere conformance of a system to any architecture cannot guarantee the system's high maintainability.The use of an inappropriate architecture can seriously undermine software maintainability at lower levels. In this article, the effect of standard architectural patterns on software maintainability quality attributes is investigated. We develop a quality model for maintainability quality attributes, which is later used to compare various standard architectural patterns.We finish by investigating two realworld experiences regarding the application of a particular pattern to two different existing architectures, exploring the effect of the change in architecture on maintainability quality attributes.
0

81
102


Mohammad
Tanhaei
Department of Engineering, Ilam University
Iran
m.tanhaei@ilam.ac.ir


Zahed
Rahmati
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
zrahmati@aut.ac.ir
Patterns
Software Architecture
Maintainability
1

On some aspects of measure and probability logics and a new logical proof for a theorem of Stone
https://ajmc.aut.ac.ir/article_4273.html
10.22060/ajmc.2021.19318.1045
1
One of the functions of mathematical logic is studying mathematical objects and notions by logical means. There are several important representation theorems in analysis. Amongst them, there is a wellknown classical one which concerns probability algebras. There are quite a few proofs of this result in the literature. This paper pursues two main goals. One is to consider some aspects of measure and probability logics and expose a novel proof for the mentioned representation theorem using ideas from logic and by application of an important result from model theory.The second and even more important goal is to present more connections between two fields of analysis and logic and reveal more the strength of logical methods and tools in analysis. The paper is mostly written for general mathematicians, in particular the people who are active in analysis or logic as the main audience. It is selfcontained and includes all prerequisites from logic and analysis.
0

103
108


Alireza
Mofidi
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
mofidi@aut.ac.ir
Integration and probability logics
Representations and measure existence theorems
Compactness in logic
1

The complexity of cost constrained vehicle scheduling problem
https://ajmc.aut.ac.ir/article_4274.html
10.22060/ajmc.2021.19454.1046
1
This paper considered the cost constrained vehicle scheduling problem under the constraint that the total number of vehicles is known in advance. Each depot has a different time processing cost. The goal of this problem is to find a feasible minimum cost schedule for vehicles. A mathematical formulation of the problem is developed and the complexity of the problem when there are more than two depots is investigated. It is proved that in this case, the problem is NPcomplete. Also, it is showed that there is not any constant ratio approximation algorithm for the problem, i.e., it is in the complexity class APX.
0

109
115


Malihe
Niksirat
Department of Computer Science, Faculty of Computer and Industrial Engineering, Birjand University of Technology, Birjand, Iran
Iran
niksirat@birjandut.ac.ir


Seyed Naser
Hashemi
Department of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
Iran
nhashemi@aut.ac.ir
Vehicle scheduling problem
Fixed job scheduling
NPcomplete
Approximation algorithm
APX