Browsing by Author "Sina Etemad"

Now showing 1 - 5 of 5
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    A new study on the existence and stability to a system of coupled higher-order nonlinear BVP of hybrid FDEs under the p-Laplacian operator
    (American Institute of Mathematical Sciences, 2022) Abdulwasea Alkhazzan; Wadhah Al-Sadi; Varaporn Wattanakejorn; Hasib Khan; Thanin Sitthiwirattham; Sina Etemad; Shahram Rezapour; T. Sitthiwirattham; Mathematics Department, Faculty of Science and Technology, Suan Dusit University, Bangkok, 10300, Thailand; email: thanin_sit@dusit.ac.th; S. Rezapour; Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, Iran; email: sh.rezapour@azaruniv.ac.ir
    In this paper, we study a general system of fractional hybrid differential equations with a nonlinear _p-operator, and prove the existence of solution, uniqueness of solution and Hyers-Ulam stability. We use the Caputo fractional derivative in this system so that our system is more general and complex than other nonlinear systems studied before. To establish the results, Green functions are used to transform the considered hybrid boundary problem into a system of fractional integral equations. Then, with the help of the topological degree theorem, we derive some sufficient conditions that ensure the existence and uniqueness of solutions for the proposed system. Finally, an example is presented to show the validity and correctness of the obtained results. © 2022 the Author(s), licensee AIMS Press.
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    A new version of (p, q) -HermiteÐHadamardÕs midpoint and trapezoidal inequalities via special operators in (p, q) -calculus
    (Springer Science and Business Media Deutschland GmbH, 2022) Thanin Sitthiwirattham; Muhammad Aamir Ali; HŸseyin Budak; Sina Etemad; Shahram Rezapour; S. Rezapour; Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, Iran; email: sh.rezapour@azaruniv.ac.ir
    In this paper, we conduct a research on a new version of the (p, q) -HermiteÐHadamard inequality for convex functions in the framework of postquantum calculus. Moreover, we derive several estimates for (p, q) -midpoint and (p, q) -trapezoidal inequalities for special (p, q) -differentiable functions by using the notions of left and right (p, q) -derivatives. Our newly obtained inequalities are extensions of some existing inequalities in other studies. Lastly, we consider some mathematical examples for some (p, q) -functions to confirm the correctness of newly established results. © 2022, The Author(s).
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    A Study on Dynamics of CD4+ T-Cells under the Effect of HIV-1 Infection Based on a Mathematical Fractal-Fractional Model via the Adams-Bashforth Scheme and Newton Polynomials
    (MDPI, 2022) Hashem Najafi; Sina Etemad; Nichaphat Patanarapeelert; Joshua Kiddy K. Asamoah; Shahram Rezapour; Thanin Sitthiwirattham; S. Rezapour; Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, 3751-71379, Iran; email: sh.rezapour@azaruniv.ac.ir; T. Sitthiwirattham; Mathematics Department, Faculty of Science and Technology, Suan Dusit University, Bangkok, 10300, Thailand; email: thanin_sit@dusit.ac.th
    In recent decades, AIDS has been one of the main challenges facing the medical community around the world. Due to the large human deaths of this disease, researchers have tried to study the dynamic behaviors of the infectious factor of this disease in the form of mathematical models in addition to clinical trials. In this paper, we study a new mathematical model in which the dynamics of CD4+ T-cells under the effect of HIV-1 infection are investigated in the context of a generalized fractal-fractional structure for the first time. The kernel of these new fractal-fractional operators is of the generalized Mittag-Leffler type. From an analytical point of view, we first derive some results on the existence theory and then the uniqueness criterion. After that, the stability of the given fractal-fractional system is reviewed under four different cases. Next, from a numerical point of view, we obtain two numerical algorithms for approximating the solutions of the system via the Adams-Bashforth method and Newton polynomials method. We simulate our results via these two algorithms and compare both of them. The numerical results reveal some stability and a situation of lacking a visible order in the early days of the disease dynamics when one uses the Newton polynomial. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
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    Investigation of the stochastic modeling of covid-19 with environmental noise from the analytical and numerical point of view
    (MDPI, 2021) Shah Hussain; Elissa Nadia Madi; Hasib Khan; Sina Etemad; Shahram Rezapour; Thanin Sitthiwirattham; Nichaphat Patanarapeelert; S. Rezapour; Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, 53751-71379, Iran; email: sh.rezapour@azaruniv.ac.ir; T. Sitthiwirattham; Mathematics Department, Faculty of Science and Technology, Suan Dusit University, Bangkok, 10300, Thailand; email: thanin_sit@dusit.ac.th; N. Patanarapeelert; Department of Mathematics, Faculty of Applied Science, King MongkutÕs University of Technology North Bangkok, Bangkok, 10800, Thailand; email: nichaphat.p@sci.kmutnb.ac.th
    In this article, we propose a novel mathematical model for the spread of COVID-19 involving environmental white noise. The new stochastic model was studied for the existence and persistence of the disease, as well as the extinction of the disease. We noticed that the existence and extinction of the disease are dependent on R0 (the reproduction number). Then, a numerical scheme was developed for the computational analysis of the model; with the existing values of the parameters in the literature, we obtained the related simulations, which gave us more realistic numerical data for the future prediction. The mentioned stochastic model was analyzed for different values of s1, s2 and b1, b2, and both the stochastic and the deterministic models were compared for the future prediction of the spread of COVID-19. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
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    On New Estimates of q-HermiteÐHadamard Inequalities with Applications in Quantum Calculus
    (MDPI, 2023) Saowaluck Chasreechai; Muhammad Aamir Ali; Muhammad Amir Ashraf; Thanin Sitthiwirattham; Sina Etemad; Manuel De la Sen; Shahram Rezapour; S. Etemad; Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, 3751-71379, Iran; email: sina.etemad@azaruniv.ac.ir; S. Rezapour; Department of Mathematics, Azarbaijan Shahid Madani University, Tabriz, 3751-71379, Iran; email: sh.rezapour@azaruniv.ac.ir; M.D.L. Sen; Institute of Research and Development of Processes, Department of Electricity and Electronics, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, 48940, Spain; email: manuel.delasen@ehu.eus
    In this paper, we first establish two quantum integral (q-integral) identities with the help of derivatives and integrals of the quantum types. Then, we prove some new q-midpoint and q-trapezoidal estimates for the newly established q-Hermite-Hadamard inequality (involving left and right integrals proved by Bermudo et al.) under q-differentiable convex functions. Finally, we provide some examples to illustrate the validity of newly obtained quantum inequalities. © 2023 by the authors.