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Öğe 3D numerical study and comparison of thermal-flow performance of various annular finned-tube designs(Shanghai Jiaotong University, 2022) Tahrour, Farouk; Ahmad, Hijaz; Ameur, Houari; Saeed, Tareq; Abu-Zinadah, Hanaa; Menni, YounesWith the increase of heat transfer problems in marine vehicles and submerged power stations in oceans, the search for an efficient finned-tube heat exchanger has become particularly important. The purpose of the present investigation is to analyze and compare the thermal exchange and flow characteristics between five different fin designs, namely: a concentric circular finned-tube (CCFT), an eccentric circular finned-tube (ECFT), a perforated circular finned-tube (PCFT), a serrated circular finned-tube (SCFT), and a star-shaped finned-tube (S-SFT). The fin design and spacing impact on the thermal-flow performance of a heat exchanger was computed at Reynolds numbers varying from 4,300 to 15,000. From the numerical results, and when the fin spacing has been changed from 2 to 7 mm, an enhancement in the Colburn factor and a reduction in the friction factor and fin performances were observed for all cases under study. Three criteria were checked to select the most efficient fin design: the performance evaluation criterion PEC, the global performance criterion GPC, and the mass global performance criterionMG. Whatever the value of Reynolds number, the conventional CCFT provided the lowest performance evaluation criterion PEC, while the SCFT gave the highest amount of PEC. The most significant value of GPC was reached with the ECFT; however, GPC remained almost the same for CCFT, PCFT, SCFT, and S-SFT. In terms of the mass global performance criterion, the S-SFT provides the highest MGpcas compared with the full fins of CCFT (41–73% higher) and ECFT (29–54% higher). Thus, the heat exchanger with S-SFT is recommended to be used in the cooling of offshore energy systems.Öğe Analyses of structural and electrical properties of aluminium doped ZnO-NPs by experimental and mathematical approaches(Elsevier, 2022) Mahmood, Arslan; Munir, Tariq; Fakhar-E-Alam, M.; Atif, Muhammad; Shahzad, Kaleem; Alimgeer, K. S.; Gia, Tuan Nguyen; Ahmad, Hijaz; Ahmad, ShafiqPure and aluminium doped ZnO-NPs were played the central role in every field of life due to extraordi-nary physical, chemical and electrical properties. The main objective of the present research was used to enhance the electrical conductivity and reduce the electrical resistivity of aluminium doped zinc oxide-NPs. Synthesis of pure and aluminium doped zinc oxide-NPs (Zn1-xAlxO) at x = 0, 2.5, 5, 7.5 and 10 wt% was carried out by co-precipitation method. The XRD results depicted that hexagonal wurtzite crystal structure and crystallite size in the range of 13-25 nm were calculated by using Debye-Scherrer's equa-tion. Likewise, the non-uniform, irregular and pore like surface morphology of the prepared NPs was evi-dent from SEM micrographs. Various functional groups (CH, CO, OH and ZnO) attached to the surface of aluminium doped zinc oxide-NPs were identified by FTIR analysis. The UV-VIS spectra also depicted a shift towards the blue region of the visible spectrum. In terms of electrical properties with the help of experimental and mathematical analyses of aluminum doped zinc oxide-NPs exhibited higher conductiv-ity (1.34 x 10(-6) to 1.43 x 10(-3) S/cm) and lower resistivity (5.46 x 10(5) to 6.99 x 10(2) Omega-cm). The present results suggest that the aluminum doped zinc oxide-NPs have been improved the structural and electrical properties which make it a good candidate for optoelectronic devices. (c) 2021 The Authors. Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Öğe Approximate series solutions of a one-factor term structure model for bond pricing(World Scientific, 2022) Edeki, Sunday Onos; Okoli, Deborah Chikwado; Ahmad, Hijaz; Wong, Wing-KeungHousehold consumption and the variables driving it have garnered extensive attention in economic literature. GDP per capita, gross savings, and inflation are among the macroeconomic variables typically considered to affect household spending. The paper examines the effect of these macroeconomic variables on household consumption using the ARDL model. The yearly aggregate data utilized in this analysis spans the period from 1983 to 2018. The paper found a long-run negative relation between household final consumption expenditure and gross domestic saving in the long run. The study showed positive and significant long-run relationships between GDP per capita and household consumption and a significant and negative relationship between savings and household consumption both in the short and long runs.Öğe Combination of the Parallel/Counter Flows Nanofluid Techniques to Improve the Performances of Double-Tube Thermal Exchangers(Springer Science and Business Media Deutschland GmbH, 2022) Lahmer, Djelloul; Benamara, Nabil; Ahmad, Hijaz; Ameur, Houari; Boulenouar, AbdelkaderThe Al2O3 (aluminum oxide)-water nanofluid is utilized in this study to improve the overall performance of a parallel flow thermal exchanger with two coaxial tubes. Numerically, the impacts of hot fluid flow, flow direction, and nanoparticle volume fraction on thermal fields, Nusselt number, and device performance are investigated. The hot fluid’s Reynolds number ranges between 3054 and 7636, whereas the cold fluid’s is set at 3000. The two-equation k-? SST turbulence model is used to accomplish the numerical simulation. The validation of numerical findings reveals a satisfactory match with the experimental reported values. The obtained results reveal positive effects of increasing fluid flow rates and nanoparticles concentration on the performance of the double-tube thermal device and Nusselt number, especially in the counter flows configuration.Öğe Different scenarios to enhance thermal comfort by renewable-ecological techniques in hot dry environment(Elsevier Ltd, 2022) Sakhri, Nasreddine; Ahmad, Hijaz; Shatanawi, Wasfi; Menni, Younes; Ameur, Houari; Botmart, ThongchaiRecently, building thermal studies have focused more and more on providing the right living conditions inside buildings, houses, schools, hospitals, etc., especially in hot-dry regions to defeat energy consumption dilemmas generally coming from fossil fuels source by renewable energy. In this paper, a field of experiments in actual conditions is conducted to investigate the influence of external parameters on the occupant's thermal comfort inside a typical dry region house. The obtained results are projected directly on the psychometric chart to position the real thermal comfort current situation. The results confirm the direct influence and indirect influence of external climatic conditions (temperature and humidity, respectively) on internal comfort. Two scenarios with renewable techniques are investigated experimentally based on the obtained results. An earth-to-air heat exchanger (EAHE) and solar chimney (SC) are connected separately to a similar building, and parameters affecting thermal comfort are discussed. The results show that both techniques improve thermal comfort inside the structure with efficiently saving energy. Renewable energy can enhance thermal comfort with significant power- and cost-saving in hot-dry regions.Öğe Diverse optical soliton solutions of the fractional coupled (2 + 1)-dimensional nonlinear Schrödinger equations(Springer, 2022) Islam, Md. Tarikul; Akbar, Md. Ali; Ahmad, HijazFractional nonlinear models involving the underlying mechanisms of numerous complicated physical phenomena arising in nature of real world have been taken major place of research arena during the couple of years for their significant roles. The study about the nonlinear optical and quantum context connecting to mostly Kerr law media as well as power law, dual-power law, triple-power law, saturable law, logarithm law and polynomial low is increasing at an inconceivable rate. In this exploration, the integrable generalized (2 + 1)-dimensional nonlinear Schrödinger system of equations in the sense of conformable fractional derivative is considered to unravel by means of two innovative schemes namely improved tanh method and rational (G?/ G) -expansion method. The advised techniques are employed to seek for appropriate analytic wave solutions after converting the mentioned equation to an ordinary differential equation by introducing a wave variable alteration. The hyperbolic, trigonometric and rational function solutions are successfully gained and put forwarded for graphical representations. The assembled solutions are figured out in 3-D, 2-D and contour formats to illustrate their different views which appeared as kink type, anti-kink type, singular kink type, bell shape, anti-bell shape, singular bell shape, cuspon, peakon, periodic and singular periodic etc. The entire study bears the diversity and novelty of found solutions and applied techniques after making a comparable study with recent work recorded in the literature.Öğe Exact Analytical Solutions for Fractional Partial Differential Equations via an Analytical Approach(American Institute of Physics Inc., 2023) Jassim, Hassan Kamil; Salman, Ali Thamir; Ahmad, Hijaz; Zayir, Muslim Yusif; Shuaa, Ali HusseinThe fractional Elzaki homotopy perturbation technique (FEHPM) is an excellent analytical tool employed in this study to solve the fractional Burger's and the Bratu's equations. The result of the suggested approach is stated as a series of components that converges to the precise solution of the problem. To show the applicability of the recommended technique, examples are presented.Öğe Exact analytical wave solutions for space-time variable-order fractional modified equal width equation(Elsevier, 2022) Ali, Umair; Ahmad, Hijaz; Baili, Jamel; Botmart, Thongchai; Aldahlan, Maha A.The variable-order evolution equation is an impressive mathematical model that explain complex dynamical problems efficiently and accurately. This latest research investigates the modified equal width nonlinear space–time variable-order fractional differential equation and fractional derivative operator in the sense of Caputo. Using transformation, an ordinary differential equation is obtained from the variable-order differential equation. For accuracy, the space–time variable-order fractional modified equal width equation is solved by the modified (G’/G) -expansion method. This model describes the simulation for one-dimensional wave transmission in nonlinear media with dispersion processes. As a result, new traveling wave solutions are developed for various values of parameters. The obtained solutions have several applications in a recent area of research in mathe- matical physics. The obtained graphical solutions are in the form of singular solitons, kink solitons and periodic solitons waves which demonstrate that the physical signifance and dynamical behaviors of fractional variable- order differential equations and the proposed method are more effective, powerful, and easy in solving prob- lems arising in mathematical physicsÖğe Fractal Hadamard-Mercer-Type inequalities with applications(World Scientific, 2022) Butt, Saad Ihsan; Yousaf, Saba; Younas, Muhammad; Ahmad, Hijaz; Yao, Shao-WenFractal analysis is a totally new area of research based on local fractional calculus. It has interesting applications in various fields such as a complex graph, computer graphics, the music industry, picture compression and many more fields. In this paper, we present new variants of Hadamard-Mercer-type inequalities on fractal sets R? (0 < ? ? 1) by employing generalized convex function. We establish two new lemmas involving local fractional integrals. By using these lemmas, we obtain several results related to generalized Hadamard-Mercer-type integral inequalities for local differentiable generalized convex functions on real linear fractal space. Finally, we give applications for probability density functions and compute new generalized means.Öğe Fractional mathematical modeling of malaria disease with treatment & insecticides(Elsevier, 2022) Sinan, Muhammad; Ahmad, Hijaz; Ahmad, Zubair; Baili, Jamel; Murtaza, Saqib; Aiyashi M.A.; Botmart, ThongchaiMany fatal diseases spread through vertical transmission while some of them spread through horizontal transmission and others transmit through both modes of transmission. Horizontal transmission illnesses are usually carried by a vector, which might be an animal, a bird, or an insect. Plasmodium parasites that dwell in red blood cells produce malaria, an infectious illness. This parasite is mostly transmitted to humans via mosquitoes. The dynamics of Malaria illness among human persons and vectors are examined in this study. The impact of the vector (mosquito) on disease transmission is also taken into account. The problem is described using nonlinear ODEs that are then generalized using the Atangana–Baleanu fractional derivative. Some theoretical analyses such as existence and uniqueness and stability via Ulam–Hyres stability analysis and optimal control strategies have been done. The numerical solution has been achieved via a numerical technique by implementing MATLAB software. Results of fractional, as well as classical order, are portrayed through different graphs while some figures are displayed for the global asymptotical stability of the model. From the graphical results, it can be noticed that the control parameters drastically decrease the number of infected human and vector population which will off course minimize the spread of infection among the human population. In addition to that, from the graphical results, it also be noticed that our model is globally asymptomatically stable as the solution converges to its equilibrium. Moreover, the use of bednets and insecticides can reduce the spread of infection dramatically while the impact of medication and treatment on the control of infection is comparatively less.Öğe Fully Legendre spectral collocation technique for stochastic heat equations(De Gruyter, 2021) Abdelkawy, Mohamed A.; Ahmad, Hijaz; Jeelani, Mdi Begum; S. Alnahdi, AbeerFor the stochastic heat equation (SHE), a very accurate spectral method is considered. To solve the SHE, we suggest using a shifted Legendre Gauss–Lobatto collocation approach in combination with a shifted Legendre Gauss–Radau collocation technique. A comprehensive theoretical formulation is offered, together with numerical examples, to demonstrate the technique’s performance and competency. The scheme’s superiority in tackling the SHE is demonstrated.Öğe Generalized thermoelastic responses in an infinite solid cylinder under the thermoelastic-diffusion model with four lags(Elsevier, 2022) Abouelregal, Ahmed E.; Ahmad, Hijaz; Yahya, Ahmed M.H.; Saidi, Anouar; Alfadil, HusamUnderstanding thermal diffusion through elastic materials is an important process that links the fields of temperature, strain, and mass diffusion. Certain mathematical and experimental models have been developed to explain this phenomenon, and defects flaws in the traditional theories have been discovered. In this context, a new and improved model of thermal diffusion has been introduced in which Fourier and Fick’s laws are replaced by more general formulas. The equa- tions for heat conduction and mass diffusion in the proposed model are extended to incorporate higher-order time derivatives and four lag phases. In special cases, some classical and generalized thermoelastic diffusion models may be obtained. The suggested model has been applied to investigate the thermoelastic diffusion processes in a solid cylinder caused by a possible thermal and chemical shock to its surface. The numerical findings of the thermodiffusion fields are shown and described graphically. The influence of the four-phase delay parameters on the various investigated fields has been compared between different models of thermal diffusion.Öğe Haar wavelet method for solution of variable order linear fractional integro-differential equations(AIMS Press, 2022) Amin, Rohul; Shah, Kamal; Ahmad, Hijaz; Ganie, Abdul Hamid; Abdel-Aty, Abdel-Haleem; Botmart, ThongchaiIn this paper, we developed a computational Haar collocation scheme for the solution of fractional linear integro-di erential equations of variable order. Fractional derivatives of variable order is described in the Caputo sense. The given problem is transformed into a system of algebraic equations using the proposed Haar technique. The results are obtained by solving this system with the Gauss elimination algorithm. Some examples are given to demonstrate the convergence of Haar collocation technique. For di erent collocation points, maximum absolute and mean square root errors are computed. The results demonstrate that the Haar approach is e cient for solving these equations.Öğe Modeling of dark solitons for nonlinear longitudinal wave equation in a magneto-electro-elastic circular rod(Tech Science Press, 2021) Durur, Hülya; Yokuş, Asıf; Kaya, Doğan; Ahmad, HijazIn this paper, sub equation and ? ? 1=G’ expansion methods are proposed to construct exact solutions of a nonlinear longitudinal wave equation (LWE) in a magneto-electro-elastic circular rod. The proposed methods have been used to construct hyperbolic, rational, dark soliton and trigonometric solutions of the LWE in the magnetoelectro-elastic circular rod. Arbitrary values are given to the parameters in the solutions obtained. 3D, 2D and contour graphs are presented with the help of a computer package program. Solutions attained by symbolic calculations revealed that these methods are effective, reliable and simple mathematical tool for finding solutions of nonlinear evolution equations arising in physics and nonlinear dynamics.Öğe New diverse variety for the exact solutions to Keller-Segel-Fisher system(Elsevier B.V., 2022) Zahran, Emad H.M.; Ahmad, Hijaz; Saeed, Tareq; Botmart, ThongchaiIn our current paper, we will extract new unexpected diverse variety of the exact solutions to the Keller-Segel -Fisher system (KSFS) which is a famous mathematical biological model that governs the mechanism of bacteria to discovery food and gets rid of venoms. The suggested model plays a vital rule for health of humans, animals as well as all other organisms. There are three famous different techniques are introduced for extract and document these new unexpected behaviors of the exact solutions are the [Formula presented] -expansion method, the extended simple equation method (ESEM) and the Riccati-Bernoulli Sub-ODE method (RBSODM). We will implement these three proposed techniques in the same time and in arranged sequence. Furthermore, we will document and list a comparison between our new achieved exact solutions of this model each with each other as well as the previously documented solutions by other authors who studied this model before.Öğe New fractional integral inequalities for preinvex functions involving Caputo-Fabrizio operator(AIMS Press, 2021) Tariq, Muhammad; Ahmad, Hijaz; Shaikh, Abdul Ghafoor; Sahoo, Soubhagya Kumar; Khedher, Khaled Mohamed; Gia, Tuan NguyeIt’s undeniably true that fractional calculus has been the focus point for numerous researchers in recent couple of years. The writing of the Caputo-Fabrizio fractional operator has been on many demonstrating and real-life issues. The main objective of our article is to improve integral inequalities of Hermite-Hadamard and Pachpatte type incorporating the concept of preinvexity with the Caputo-Fabrizio fractional integral operator. To further enhance the recently presented notion, we establish a new fractional equality for differentiable preinvex functions. Then employing this as an auxiliary result, some refinements of the Hermite-Hadamard type inequality are presented. Also, some applications to special means of our main findings are presented.Öğe Novel analysis of hermite-hadamard type integral inequalities via generalized exponential type m-convex functions(MDPI, 2022) Tariq, Muhammad; Ahmad, Hijaz; Cesarano, Clemente; Abu-Zinadah, Hanaa; Abouelregal, Ahmed E.; Askar, SamehThe theory of convexity has a rich and paramount history and has been the interest of intense research for longer than a century in mathematics. It has not just fascinating and profound outcomes in different branches of engineering and mathematical sciences, it also has plenty of uses because of its geometrical interpretation and definition. It also provides numerical quadrature rules and tools for researchers to tackle and solve a wide class of related and unrelated problems. The main focus of this paper is to introduce and explore the concept of a new family of convex functions namely generalized exponential type m-convex functions. Further, to upgrade its numerical significance, we present some of its algebraic properties. Using the newly introduced definition, we investigate the novel version of Hermite-Hadamard type integral inequality. Furthermore, we establish some integral identities, and employing these identities, we present several new Hermite-Hadamard H-H type integral inequalities for generalized exponential type m-convex functions. These new results yield some generalizations of the prior results in the literature.Öğe Numerical comparison of Caputo and Conformable derivatives of time fractional Burgers-Fisher equation(Elsevier, 2021) Yokuş, Asıf; Durur, Hülya; Kaya, Doğan; Ahmad, Hijaz; Nofal, Taher A.In this paper, the sub-equation method is used to obtain new types of complex traveling wave solutions of the time-fractional Burgers-Fisher equation. In this work is to compare the exact complex traveling wave solutions of new types and the numerical solutions obtained by suitable transformations of Caputo and Conformable de-rivatives. Also, to discuss the advantages and disadvantages of those derivatives and a new initial condition was created by using the obtained solution and the numerical solutions of the equation were obtained by the finite difference method. A comparison of the numerical solutions with the obtained exact solution is made. L2 and L? norm errors, absolute error values, Von Neumann stability analysis supporting this comparison are investigated. To consolidate the accuracy of the numerical results some tables and graphs are presented. For drawing complex mathematical operations and graphs, computer package programs are usedÖğe Optimal backstepping-fopıd controller design for wheeled mobile robot(International Information and Engineering Technology Association, 2022) Euldji, Rafik; Batel, Noureddine; Rebhi, Redha; Kaid, Noureddine; Tearnbucha, Chutarat; Sudsutad, Weerawat; Lorenzini, Giulio; Ahmad, Hijaz; Ameur, Houari; Menni, YounesA design of an optimal backstepping fractional order proportional integral derivative (FOPID) controller for handling the trajectory tracking problem of wheeled mobile robots (WMR) is examined in this study. Tuning parameters is a challenging task, to overcome this issue a hybrid meta-heuristic optimization algorithm has been utilized. This evolutionary technique is known as the hybrid whale grey wolf optimizer (HWGO), which benefits from the performances of the two traditional algorithms, the whale optimizer algorithm (WOA) and the grey wolf optimizer (GWO), to obtain the most suitable solution. The efficiency of the HWGO algorithm is compared against those of the original algorithms WOA, GWO, the particle swarm optimizer (PSO), and the hybrid particle swarm grey wolf optimizer (HPSOGWO). The simulation results in MATLAB–Simulink environment revealed the highest efficiency of the suggested HWGO technique compared to the other methods in terms of settling and rise time, overshoot, as well as steady-state error. Finally, a star trajectory is made to illustrate the capability of the mentioned controllerÖğe Propagation of some new traveling wave patterns of the double dispersive equation(De Gruyter Open Ltd, 2022) Asjad, Muhammad Imran; Faridi, Waqas Ali; Jhangeer, Adil; Ahmad, Hijaz; Abdel-Khalek, Sayed; Alshehri, NawalSciVal Topics Metrics Funding details Abstract This article aims to address the exact solution of the prestigious partial differential equation, namely, a double dispersive equation. Here, we are obtaining some new traveling wave solutions of the double dispersive equation with the more general mathematical technique, which is a direct algebraic extended method. This proposed technique is more general and integrated. The obtained solutions contain dark, bright, dark-bright, singular, periodic, kink, and rational function solutions. More illustration of traveling wave solutions of the double dispersive equation is given by plotting the two- and three-dimensional graphs with the suitable selection of parameters. This graphical presentation of solutions identifies the pattern of wave propagation. The acquired consequences are new and may play a significant role to examine the physical phenomena of wave propagation, where this model is used.
