Amirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301On general $(\alpha,\beta)$-metrics with Cartan torsion, mean Cartan torsion and Landsberg curvature105112479410.22060/ajmc.2022.21094.1077ENManojKumarDepartment of Mathematics and Statistics Faculty of Science, Dr. Rammanohar Lohia Avadh University, Ayodhya-224001, IndiaChayan KumarMishraDepartment of Mathematics and Statistics Faculty of Science, Dr. Rammanohar Lohia Avadh University, Ayodhya-224001, IndiaAbhishekSinghDepartment of Mathematics and Statistics Faculty of Science, Dr. Rammanohar Lohia Avadh University, Ayodhya-224001, IndiaAchalSinghDepartment of Mathematics Institute of Applied Sciences and Humanities GLA University Mathura-281406, IndiaJournal Article20220210In this paper, we derive a formula for the (mean) Cartan torsion of a class of general $(\alpha,\beta)$-metrics. Also, we study weak Landsberg general $(\alpha,\beta)$-metrics under a certain condition.https://ajmc.aut.ac.ir/article_4794_b3d3b3ec9cc76f30137d8d48ae9b0788.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301Computation of $\mu$-symmetry and $\mu$-conservation law for the Camassa-Holm and Hunter-Saxton equations113122494610.22060/ajmc.2022.21712.1102ENSomayehShabanDepartment of Mathematics, Karaj branch, Islamic Azad University, Karaj, IranMehdiNadjafikhahDepartment of Pure Mathematics, School of Mathematics, Iran University of Science and Technology, Narmak, Tehran, Iran0000-0002-1354-9786Journal Article20220822This work is intended to compute the $\mu$-symmetry and $\mu$-conservation laws for the Cammasa-Holm (CH) equation and the Hunter-Saxton (HS) equation. In other words, $\mu$-symmetry, $\mu$-symmetry reduction, variational problem, and $\mu$-conservation laws for the CH equation and the HS equation are provided. Since the CH equation and the HS equation are of odd order, they do not admit a variational problem. First we obtain $\mu$-conservation laws for both of them in potential form because they admit a variational problem and then using them, we obtain $\mu$-conservation laws for the CH equation and the HS equation.https://ajmc.aut.ac.ir/article_4946_9a66e5a1235c490396ad417291e32962.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301On $m$-th root metrics of isotropic projective Ricci curvature123128498410.22060/ajmc.2022.21830.1113ENMehranGabraniDepartment of Mathematics, Faculty of Science, Urmia University, Urmia, Iran0000-0002-4489-0477BahmanRezaeiDepartment of Mathematics, Faculty of Science, Urmia University, Urmia, IranEsraSengelen SevimDepartment of Mathematics, Istanbul Bilgi University, 34060, Eski Silahtaraga Elektrik Santrali, Kazim Karabekir Cad. No: 2/13
Eyupsultan, Istanbul, TurkeyJournal Article20221007The Ricci curvature is introduced by spray on $M^n$. Sprays are deformed to projective sprays with a volume form $dV$ on $M^n$. The projective Ricci curvature is defined as the expression of Ricci curvature with sprays. With this paper, we use the new notion that is called weakly isotropic projective Ricci curvature. We have introduced the idea of weakly isotropic projective Ricci curvature in \cite{GRS21Square}. Then we study and characterize $m$-th root metrics of weakly isotropic projective Ricci curvature. We obtain that every $m$-th root metric of weakly isotropic projective Ricci curvature is projectively Ricci-flat.https://ajmc.aut.ac.ir/article_4984_d4e3dfadefb336a079e5cb9dd58bfac2.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301Biamenability of Banach algebras and its applications129136495210.22060/ajmc.2022.21859.1115ENSedighehBarootkoobFaculty of Basic Sciences, University of Bojnord, P.O. Box 1339, Bojnord,
IranSomayehMohammadzadehFaculty of Basic Sciences, University of Bojnord, P.O. Box 1339, Bojnord,
IranJournal Article20221015In this paper, we introduce the concept of biamenability of Banach algebras and we show that despite the apparent similarities between amenability and biamenability of Banach algebras, they lead to very different, and somewhat opposed, theories. In this regard, we show that commutative Banach algebras and the group algebra $L^1(G)$, for each locally compact group $G$, tend to lack biamenability, while they may be amenable and highly non-commutative Banach algebras such as $B(H)$ for an infinite-dimensional Hilbert space $H$ tend to be biamenable, while they are not amenable. Also, we show that although the unconditional unitization of an amenable Banach algebra is amenable but in general unconditional unitization of a Banach algebra is not biamenable. This concept may be applied for studying the character space of some Banach algebras and also for studying some spansion or density problems.https://ajmc.aut.ac.ir/article_4952_57e3902c61aa35c062d4b3f4e894c38e.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301Detecting semi-referees in the Plackett-Luce model137144500110.22060/ajmc.2022.20659.1072ENOmidNaghshineh ArjmandDepartment of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran0000-0002-7435-2733NastaranMirzaeiShahrood University of Technology, IranJournal Article20211013In this paper, we use the Plackett-Luce model for detecting some referees who judge arbitrariness with inaccuracy or without paying enough attention, which is called Semi-referees. We will investigate our method by simulation and sample of real data.https://ajmc.aut.ac.ir/article_5001_768e622cfc57033d315fc8ad8bff388f.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301Predicting content-based political inclinations of Iranian Twitter users using BERT and deep learning145154502310.22060/ajmc.2022.21895.1120ENAliRahmatiFaculty of Computer Engineering,
Malek-Ashtar University of Technology, Tehran, IranEhsanTavanFaculty of Computer Engineering,
Malek-Ashtar University of Technology, Tehran, IranMohammad AliKeyvanradFaculty of Computer Engineering,
Malek-Ashtar University of Technology, Tehran, IranJournal Article20221031Along with the advent of social networks such as Twitter; Politicians, social media, and ordinary citizens regularly turn to them to share their thoughts and feelings, such as political views. This article analyzes the political ideology of Iranian Twitter users using deep learning and combining the deep layers of LSTM and CNN with BERT, enabling us to target groups of sympathizers and opponents of the Islamic Republic of Iran that is of particular interest to political scientists. We trained a model for predicting whether a tweet is a sympathizer or opponent, using a novel dataset from Twitter, including tweets from sympathizers and opponent people. Then, using the trained model, the people’s ideology can be identified. The results show that using the proposed model, tweets can be categorized with a 75.68% F1-Score, and the classification of individuals based on political orientation to a 93.18% F1-Score can be done correctly.https://ajmc.aut.ac.ir/article_5023_3d7cca4977db8d7eb55e4fc8f17345a3.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301Bergman and Dirichlet spaces in the unit ball and symmetric lifting operator155160500510.22060/ajmc.2022.21778.1107ENMostafaHassanlouEngineering Faculty of Khoy, Urmia University of Technology, Urmia, IranEbrahimAbbasiDepartment of Mathematics, Mahabad Branch, Islamic Azad University, Mahabad, IranJournal Article20220916Let $\mathbb{B}_n$ be the open unit ball in $\mathbb{C}^n$ and $\mathbb{B}_n^2 = \mathbb{B}_n \times \mathbb{B}_n$. The symmetric lifting operator which lifts analytic functions from $H(\mathbb{B}_n)$ to $H(\mathbb{B}_n^2)$ is defined as follow<br />\[<br />L(f)(z,w) = \frac{f(z) - f(w)}{z-w}.<br />\]<br />In this paper we investigate the action of symmetric lifting operator on the Bergman space in the unit ball. Also, we state a characterization for Dirichlet space and consider symmetric lifting operator on the Dirichlet space in the unit ball.https://ajmc.aut.ac.ir/article_5005_406b2153e9a979a51060d31b7bcbf7cc.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301Betterment for estimates of the numerical radii of Hilbert space operators161167501610.22060/ajmc.2022.21907.1122ENMohammadDavarpanahDepartment of Mathematics, Ferdows Branch, Islamic Azad University, Ferdows, IranHamid RezaMoradiDepartment of Mathematics, Payame Noor University (PNU), P.O. Box, 19395-4697, Tehran, Iran0000-0002-0233-0455Journal Article20221103We give several inequalities involving numerical radii $\omega \left( \cdot \right)$ and the usual operator norm $\|\cdot\|$ of Hilbert space operators. These inequalities lead to a considerable improvement in the well-known inequalities<br />\begin{equation*}<br />\frac{1}{2}\left\| T \right\|\le \omega \left( T \right)\le \left\| T \right\|.<br />\end{equation*}https://ajmc.aut.ac.ir/article_5016_055edb1e472fa4dbb3fcc9f92b1b2178.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301A Bi-level formulation for a sequential stochastic attacker-defender game via conditional value at risk169181489110.22060/ajmc.2022.21642.1096ENNaderBiranvandImam Ali University, Faculty of sciences, Department of mathematics, Tehran, IranMohammadMoghaddasImam Ali University, Faculty of sciences, Department of mathematics, Tehran, IranMortezaMalekniaImam Ali University, Faculty of sciences, Department of mathematics, Tehran, IranJournal Article20220730In this study, we present a bi-level formulation for a sequential stochastic attacker-defender game with multiple targets. In this game, the vulnerability of targets is a stochastic parameter, and the attacker has only one attack type. The defender’s aim is to find the optimal allocation of the budget to minimize the conditional value at risk of damage. In response to the defender’s decisions, the attacker seeks an optimal allocation of its budget to maximize the expected damage. By using Karush-Kuhn-Tucker transformations, we reduce the proposed bi-level formulation to a single-level one. We also explore some important relationships between the solutions of the single-level and bi-level problems. Finally, by means of numerical experiments, we apply our formulation to several stochastic attacker-defender games to show the efficiency of our formulation in practice.https://ajmc.aut.ac.ir/article_4891_762cd9b22596cee1dc0f44d9fce2def2.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301The warped generalized Lagrange space and its application in physics183193478310.22060/ajmc.2022.20992.1076ENYousefAlipour FakhriDepartment of Mathematics, Payame Noor University, 19395-3697, Tehran, Iran0000-0002-7085-2896MojtabaGarossiDepartment of Complementary Education, Payame Noor University, Tehran, IranJournal Article20220114In this paper, we define the warped generalized Lagrangian (WGL) spaces and then examine some of their properties. In the following, we generalize the ``Tavakol-van den Bergh" condition in the theory of relativity (see 5) in this space, which is an example of the application of the warped generalized Lagrangian spaces in relativity (Theorem 4.6). We show that condition EPS in these spaces holds provided that the warped function $f$ satisfies the condition $\Big(e^{2f}\Big)^i=0$.https://ajmc.aut.ac.ir/article_4783_00a381b6708c57e74fd616b1b8fc3acf.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301Non-classical symmetry and new exact solutions of the Kudryashov-Sinelshchikov and modified KdV-ZK equations195203501010.22060/ajmc.2022.21656.1097ENMehdiJafariDepartment of Mathematics, Payame Noor University, PO BOX 19395-3697, Tehran, IranSomayehalsadatMahdionDepartment of Mathematics, Payame Noor University, PO BOX 19395-3697, Tehran, IranJournal Article20220802In this paper, by applying the non-classical symmetry method, non-classical symmetries of the Kodryashov-Sinleschikov (K-S) and modified Korteweg-de Vries-Zaharov-Kuznetsov (mKdV-ZK) equations are obtained. Apart from classical symmetries, this theory can be effective in finding a few other solutions for a system of PDEs and ODEs. Also, non-classical symmetries of a system of PDEs can be applied to reduce the number of independent variables. By adding the<br />invariance surface condition to the assumed equations and applying the classical symmetry method for them, non-classical symmetries are calculated. Finally, some of the group invariant solutions and the similarity reduced equations associated to non-classical symmetry are obtained.https://ajmc.aut.ac.ir/article_5010_f076c75f29340b476cbb3d314cbb8872.pdfAmirkabir University of TechnologyAUT Journal of Mathematics and Computing2783-24494220230301A new MILP model for vehicle routing-loading problem under fragility, LIFO, and rotation constraints205218487610.22060/ajmc.2022.21100.1078ENFarnazHooshmandDepartment of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran0000-0002-2449-3925S. DanialMohseniDepartment of Mathematics and Computer Science, Amirkabir University of Technology (Tehran Polytechnic), Tehran, IranJournal Article20220212Simultaneous optimization of vehicle routing and loading decisions in three-dimensional case is one of the important problems in logistics and has received great attention from researchers. To the best of our knowledge, optimization models presented in the literature for this problem either are too complicated or do not include important loading assumptions such as item fragility, last-in-first-out arrangement, and the possibility of rotation. To overcome the shortcoming of the existing models, in this paper, we present a novel mixed-integer linear programming (MILP) model which not only involves important loading assumptions, but also does not have the complexity of previous models. Moreover, we provide valid inequalities to strengthen the LP relaxation bound and accelerate the solution process. Further, we show that how a restricted version of our model can be incorporated in loading procedures of meta-heuristic algorithms to improve their efficiency. Computational results over instances, taken from the literature, show the performance of the proposed approachhttps://ajmc.aut.ac.ir/article_4876_0d6ee69bd8d1c829b86845f62be9c1d7.pdf