Publications Scientifiques
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Item Mechanical Properties of Alfa, Sisal, and Hybrid Alfa/Sisal Fiber Satin Cloth Reinforced Epoxy(Springer Nature, 2024) Baali, Besma R.; Gherbi, Mohammed Tahar; Nour, Abdelkader; Casimir, J.B.; Saci, Rachid; Aguib, Salah; Attia, Nourhane; Aribi, ChouaibThe mechanical behavior of composites, made of an epoxy resin matrix reinforced by 30 and 40% of a satin cloth from long Alfa, sisal and hybrid Alfa/sisal fibers was studied. The fibers are obtained by extraction with elimination of binders such as pectins and lignin. For each type of fibers, appropriate and optimal chemical and thermal treatments were conducted within NaOH solution, to enhance both the fiber surface quality and the interfacial bonding between fibers and matrix. Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and chemical decomposition of treated and untreated fibers lead to prove the treatment efficiency. The thermogravimetric (TGA) and differential thermogravimetric (DTG) analyses showed better thermal stability. Differential scanning calorimetry (DSC) made it possible to quantify the enthalpy changes which showed an increase in the amount of heat as a function of the increase in weight fraction of natural fibers. The endothermic reaction of the composites studied containing 30 wt% fiber reinforcement was less than that containing 40 wt% fiber reinforcement. The composite materials were produced by vacuum assisted resin transfer molding (VARTM) method due to hydrophilic nature of the fibers. The results of static tests were compared to those of pure epoxy resin. It showed a significant increase for 40 wt% woven A1lfa/epoxy of about 333, 113, and 81% in tension, 3-points bending and compression tests respectively. SEM morphology analysis revealed good interfacial adhesion between the treated fibers and the matrix.Item An efficient approach for solving differential equations in the frame of a new fractional derivative operator(MDPI, 2023) Attia, Nourhane; Akgül, Ali; Seba, Djamila; Nour, Abdelkader; la Sen, Manuel De; Bayram, MustafaRecently, a new fractional derivative operator has been introduced so that it presents the combination of the Riemann–Liouville integral and Caputo derivative. This paper aims to enhance the reproducing kernel Hilbert space method (RKHSM, for short) for solving certain fractional differential equations involving this new derivative. This is the first time that the application of the RKHSM is employed for solving some differential equations with the new operator. We illustrate the convergence analysis of the applicability and reliability of the suggested approaches. The results confirm that the RKHSM finds the true solution. Additionally, these numerical results indicate the effectiveness of the proposed methodItem A novel method for fractal-fractional differential equations(Elsevier, 2022) Attia, Nourhane; Akgül, Ali; Seba, Djamila; Nour, Abdelkader; Asad, JihadWe consider the reproducing kernel Hilbert space method to construct numerical solutions for some basic fractional ordinary differential equations (FODEs) under fractal fractional derivative with the generalized Mittag–Leffler (M-L) kernel. Deriving the analytic and numerical solutions of this new class of differential equations are modern trends. To apply this method, we use reproducing kernel theory and two important Hilbert spaces. We provide three problems to illustrate our main results including the profiles of different representative approximate solutions. The computational results are compared with the exact solutions. The results obtained clearly show the effect of the fractal fractional derivative with the M-L kernel in the obtained outcomes. Meanwhile, the compatibility between the approximate and exact solutions confirms the applicability and superior performance of the methodItem Numerical solutions to the time-fractional swift–hohenberg equation using reproducing kernel hilbert space method(Springer, 2021) Attia, Nourhane; Akgül, Ali; Seba, Djamila; Nour, AbdelkaderIn this work, a numerical approach based on the reproducing kernel theory is presented for solving the fractional Swift–Hohenberg equation (FS-HE) under the Caputo time-fractional derivative. Such equation is an effective model to describe a variety of phenomena in physics. The analytic and approximate solutions of FS-HE in the absence and presence of dispersive terms have been described by applying the reproducing kernel Hilbert space method (RKHSM). The benefit of the proposed method is its ability to get the approximate solution of the FS-HE easily and quickly. The current approach utilizes reproducing kernel theory, some valuable Hilbert spaces, and a normal basis. The theoretical applicability of the RKHSM is demonstrated by providing the convergence analysis. By testing some examples, we demonstrated the potentiality, validity, and effectiveness of the RKHSM. The computational results are compared with other available ones. These results indicate the superiority and accuracy of the proposed method in solving complex problems arising in widespread fields of technology and scienceItem Numerical solution of the fractional relaxation-oscillation equation by using reproducing kernel hilbert space method(Springer, 2021) Attia, Nourhane; Akgül, Ali; Seba, Djamila; Nour, AbdelkaderIn this article, the reproducing kernel Hilbert space is proposed and analyzed for the relaxation-oscillation equation of fractional order (FROE). The relaxation oscillation is a type of oscillator based on the way that the physical system’s returns to its equilibrium after being disturbed. We make use of the Caputo fractional derivative. The approximate solution can be obtained by taking n-terms of the analytical solution that is in term of series formula. The numerical experiments are used to prove the convergence of the approximate solution to the analytical solution. The results obtained by the given method demonstrate that it is convenient and efficient for FROEItem Modeling a Composite Reinforced with Short Alfa Fibers to Determine its Fatigue and Structural Homogenization(Springer, 2018) Nour, Abdelkader; Mechakra, Hamza; Benkoussas, B.; Tawfiq, I.; Settet, A. T.; Renane, R.The fatigue and homogenization of polypropylene reinforced with untreated and chemically treated short Alfa fibers were investigated using a modified Mori–Tanaka model. The polypropylene with chemically treated fibers showed a higher resistance than that with untreated ones. Cylindrical fibers with elliptical cross sections were used in experiments. Their mechanical characteristics were determined by the inverse method.Item Solving Duffing-Van der Pol Oscillator Equations of Fractional Order by an Accurate Technique(Shahid Chamran University of Ahvaz, 2021) Attia, Nourhane; Seba, Djamila; Akgül, Ali; Nour, AbdelkaderIn this paper, an accurate technique is used to find an approximate solution to the fractional-order Duffing-Van der Pol (DVP, for short) oscillators equation which is reproducing kernel Hilbert space (RKHS, for short ) method. The numerical results show that the n-term approximation is a rapidly convergent series representation and they present also the high accuracy and effectiveness of this method. The efficiency of the proposed method has been proved by the theoretical predictions and confirmed by the numerical experimentsItem Numerical solution for nonlinear Time-Fractional Partial differential equation with variable coefficient using reproducing kernel hibert space Method(IEEE, 2020) Attia, Nourhane; Seba, Djamila; Nour, AbdelkaderItem Study and analysis of the Magneto-Mechanical behavior of smart composite sandwich beam in elastomer(2019) Settet, Ahmed Tidjani; Aguib, Salah; Nour, Abdelkader; Zerrouni, NassimItem Vibration control of a hydrostatic bearing using magnetorheological elastomer shell bearing(JVE International, 2018) Chikh, Noureddine; Aguib, Salah; Djedid, Toufik; Nour, Abdelkader; Tawfiq, ImadIn rotating machines, random movements or sliding movements of the rotor in its housing can produce undesirable phenomena for some parts. To solve this problem, a new hydrostatic bearing with an intelligent magnetorheological elastomer sell bearing has been designed to control the undesirable vibrations of rigid rotors. The different effects of the influence parameters on the vibratory behavior of the sell bearing are calculated numerically using Abaqus software, and the results found are encouraging