Hijaz Ahmad

Hijaz Ahmad
Università Telematica Internazionale UNINETTUNO · Section of Mathematics

Mathematical Physics; Mathematical Modelling; Fluid Dynamics; Fractional Cacluls; Energy; Numerical Analysis

About

329
Publications
152,132
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3,225
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Introduction
Hijaz Ahmad (حجاز أحمد) is a Researcher with expertise and research interests in computational methods for differential equations.

Publications

Publications (329)
Article
Full-text available
In this paper, an effective modification of variational iteration algorithm-II is presented for the numerical solution of the Korteweg–de Vries-Burgers equation, Burgers equation and Kortewege–de Vries equation. In this modification, an auxiliary parameter is introduced which make sure the convergence of the standard algorithm-II. In order to asses...
Article
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In this paper, modified variational iteration algorithm-II is investigated for finding approximate solutions of nonlinear Parabolic equations. Comparisons of the MVIA-II with trigonometric B-spline collocation method, variational iteration method, homotopy perturbation transform method, Adomian decomposition method, and modified variational iterati...
Article
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The role of integer and noninteger order partial differential equations (PDE) is essential in applied sciences and engineering. Exact solutions of these equations are sometimes difficult to find. Therefore, it takes time to develop some numerical techniques to find accurate numerical solutions of these types of differential equations. This work aim...
Article
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In this investigation, the system of governing equations for a thermoelastic behavior of a rotating viscoelastic microbeam whose viscoelastic properties are incorporated in terms of the Kelvin-Voigt scheme. Furthermore, the influences of viscoelastic behavior are captured via a non-Fourier heat conduction model. This exciting viscoelastic microbeam...
Article
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The nonlinear partial differential equations having travelling or solitary wave solutions is numerically challenging, in which one of the important type is the Fornberg-Whitham model equation. This article aims to solve the Fornberg-Whitham type equations numerically via the variational iteration algorithm-I (MVIA-I). The MVIA-I gives approximate a...
Technical Report
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Poster
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http://www.aimspress.com/aimsbpoa/article/6239/special-articles
Article
Nonlinear fractional differential equations provide suitable models to describe real-world phenomena and many fractional derivatives are varying with time and space. The present study considers the advanced and broad spectrum of the nonlinear (NL) variable-order fractional differential equation (VO-FDE) in sense of VO Caputo fractional derivative (...
Article
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Fractional operators with integral inequalities have attracted the interest of several mathematicians. Fractional inequalities are best utilized in mathematical science with their features and wide range of applications in optimization, modeling, engineering and artificial intelligence. In this article, we consider new variants of Simpson-Mercer ty...
Article
Optimization for all disciplines is very important and applicable. Optimization has played a key role in practical engineering problems. A novel hybrid meta-heuristic optimization algorithm that is based on Differential Evolution (DE), Gradient Evolution (GE) and Jumping Technique named Differential Gradient Evolution Plus (DGE+) are presented in t...
Article
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In this article, we will apply the solitary wave ansatz technique and the modified stretched mapping technique to achieve the solitary wave solutions for the cubic-nonlinear Schrödinger equation which describes the slowing varying wave packets and generic small amplitude. The achieved solitary wave solutions using these two distinct techniques will...
Article
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The fractional variable-order (VO) two-dimensional (2Dim) Cable equation is one of the most significant types of anomalous subdiffusion equations that emerge strongly in spiny neural dendrites and is solved by using an accurate numerical technique in this study. The non-standard weighted average finite difference approach is a simple proposed techn...
Article
The goal of this paper is to obtain the new explicit solutions of the Atangana conformable (AC) fractional Biswas–Milovic (BM) equation with Parabolic law nonlinearity (PLN) which is a class of Schrödinger equation (SE) using a new methodology. This methodology, which is an extension of the direct algebraic method, provides some new solutions that...
Article
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In this paper, we investigate an interesting class of analytic and biunivalent functions in the open unit disk Δ which is defined using the q -derivative operator. We apply the subordination method to the functional of coefficients problem. Furthermore, we obtain the bounds of the certain functional of coefficients for functions in the class H Σ q...
Article
The goal of this study is to determine the role of the area ratio (AR) and the Reynolds number on the distribution of flow and pressure in the dividing manifold. For this purpose, five different models have been used to be analyzed under the test conditions. The first physical model is of 101.6 mm (4 in) in diameter for the master manifold in a reg...
Article
It has been known that both brain and heart produce magnetic fields however, intensity of heart magnetic field is more. The question arises that what is the relation between heart and brain waves. We answer this question by suggesting a theoretical model which use of hemoglobins and other spinors as packages of information and spin waves for exchan...
Article
In this article, new soliton solutions of Simplified Modified Camassa–Holm (SMCH) equation and Klein–Gordon-Zakharov (KGZ) equation are acquired. First Integral Method (FIM) and Exponential Function Method (EFM) are employed to construct the soliton solutions of SMCH equation and KGZ equation. The solution by these approaches can be obtained by uti...
Article
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This article deals with a new modified heat conduction model with fractional order that includes the Caputo–Fabrizio differential operator (CF) and the thermal relaxation time. This new approach to the CF fractional derivative has attracted many researchers because it includes a nonsingular kernel. The nonlocal theory proposed by Eringen has also b...
Article
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Our key objective in the present work is to elaborate the concept of activation energy in chemically reactive flow with the help of modeling and computation. The model investigated is fluid flow over a vertical cylinder in the porous medium with chemical reaction and radiation effect. The similarity transform converted the resulting constitutive eq...
Article
Nonlinear evolution equations play enormous significant roles to work with complicated physical phenomena located across the nature world. The Schrödinger type equations bearing nonlinearity are important models that flourished with the wide-ranging arena concerning plasma physics, nonlinear optics, fluid flow and the theory of deep-water waves. In...
Article
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The numerical procedure for turbulence fluid flow and heat transfer in a twisted flat tube is presented in this work. For the cross-section of the flat tube, three different geometries are investigated. Water is a working fluid with constant thermophysical properties. The Reynolds number ranges from 5000 to 20000. Results show that by using twisted...
Article
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In this paper, the newly developed fractal-fractional differential and integral operators are used to analyze the dynamics of chaotic system based on image encryption. The problem is modeled in terms of classical order nonlinear, coupled ordinary differential equations that are then generalized through fractal-fractional differential operator of Mi...
Article
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Solar thermal collectors, as well as heat exchangers, are energy systems that have become very popular recently in various research centers around the world. Clean systems used to generate thermal energy for its importance in human life. Most of the studies focused on the impact of various physical factors on the efficiency and performance of these...
Article
Working vacation queues with breakdowns and customers impatience have many applications in different real-life situations. The development of these models to determine their performance is extremely important. In this paper, we deal with a finite population Markovian multi-server machine system with breakdowns, repairs, Bernoulli feedback, balking,...
Article
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The bogie frame is the main structure of the train that supports the train's loads during its operation. These structures are subject to fatigue testing to ensure their design life is up to the required standards. The urban light rail transit (LRT) bogie frame used in the Greater Jakarta area is newly designed and manufactured by a commercial railw...
Article
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Water demand has been increasing considerably around the world, mostly since the start of the COVID-19 pandemic. It has caused many problems for water supply, especially in arid areas. Consequently, there is a need to assimilate lessons learned to ensure water security. In arid climates, evaluating the groundwater potential is critical, particularl...
Article
In this paper, the conformable Lakshmanan-Porsezian-Daniel equation with parabolic law nonlinearity is solved and the newly acquired optical solutions are analysed. To achieve this, two robust analytical techniques are implemented namely, the three-wave method and the interaction phenomena form. The newly obtained solutions are in the form of dark,...
Article
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Objectives: The purpose of this research is to synthesize the Yttrium doped PEG-coated ZnO nanostructures and characterize them especially as thermoluminescence material for gamma dosimetry. The dosimetry characteristics were evaluated by irradiating the sample with gamma radiation with different doses (10 and 100 Gray) at a temperature range of 0-...
Article
The 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...
Article
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In this article, we consider the stochastic fractional-space long-shortwave interaction system (SFS-LSWIs) forced by multiplicative Brownian motion. To obtain a new exact stochastic fractional-space solutions, we apply two different methods such as sin-cos method and the Riccati-Bernoulli sub-ODE method. These solutions are essential for explaining...
Article
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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...
Article
Objectives The purpose of this research is to synthesize the Yttrium doped PEG-coated ZnO nanostructures and characterize them especially as thermoluminescence material for gamma dosimetry. The dosimetry characteristics were evaluated by irradiating the sample with gamma radiation with different doses (10 and 100 Gray) at a temperature range of 0-4...
Article
Full-text available
In the field of maritime transport, motion and energy, the dynamics of deep-sea waves is one of the major problems in ocean science. A mathematical modeling of dynamics of solitary waves in deep sea under the two-layer stratification leads to NLS equation, and consequently, the interaction two of them can be formulated by coupled NLS equation. In t...
Article
The principal objective of this work focuses on achieving a class of advanced and impressive N-dark–dark solitons estimations to the coupled nonlinear Schrödinger system (CNLSS) that represents the propagation of optical pluses in the model-locked fiber lasers. The achieved results will perfectly describe different nonlinear coherent structures for...
Article
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Building aeration ventilation may contribute to achieve thermal comfort there by economizing huge amount of electricity that would be supplied using conventional air conditioning systems. Natural ventilation maintains thermal equilibrium between heating and cooling balances. They may also be used in conjunction with other systems in certain circums...
Article
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The current work investigates the efficiency of a Direct Methanol Fuel Cell (DMFC) by using COMSOL. The set-up model takes into consideration the electrochemical kinetics and chemical reactions. The anode catalyst layers are a main element in the PEM fuel cell; their porosity significantly affects the fuel cell efficiency. We focus on the impact of...
Article
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A 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 evoluti...
Article
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Nanoelectromechanical systems (NEMS) have received great interest from researchers around the world since the advent of nanotechnology and nanoengineering. This can be attributed due to the unique characteristics of NEMS devices and their wide range of applications. Among these applications, nanobeams and nanotubes now have an important role in the...
Article
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Fractional 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 powe...
Article
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The solitary wave results of many Boussinesq systems of equations are gained by using the Optimal Homotopy Asymptotic method with Daftardar-Jafari Polynomials. The results were intended in the form of a convergent power series with simply predictable components. The convergence of the method is well-known numerically for the system with several ini...
Article
Heat exchangers are multi-benefit thermal-devices, of wide use, as their structure varies with their scope of application. The development of channel configurations contained in these exchangers, and evaluation of their performance is the goal of many recent numerical and experimental achievements. Because of the high cost of such devices, many res...
Article
The fundamental objective of this article is to find exact solutions to the stochastic fractional-space Allen–Cahn equation, which is derived in the Itô sense by multiplicative noise. The exact solutions to this equation are required since it appears in many discipline areas including plasma physics, quantum mechanics and mathematical biology. The...
Article
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Green chemistry of nanomaterials from synthesis to diverse biomedical applications is a discussion of town in the current scientific scenario. In this work, Ocimum basilicum leaves extract was utilized as the reducing agent in the synthesis of ZnO nanoparticles. Green synthesized ZnO NPs mediated via Ocimum basilicum extract were decorated on the r...
Article
In 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 oth...
Article
With 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:...
Article
The current study focuses on the 3D nonlinear mixed convective boundary layer flow of micropolar hybrid nanofluid in the presence microorganism and multiple slip conditions across the slendering surface. The concentration and energy equations are developed in the occurrence of activation energy and joule heating effect. The aim of this research is...
Article
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Recently, 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 co...
Article
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For the stochastic heat equation (SHE), a very accurate spectral method is considered. To solve the SHE, we suggest using a shifted Legendre Gauss-Lobatto collo-cation approach in combination with a shifted Legendre Gauss-Radau collocation technique. A comprehensive theoretical formulation is offered, together with numerical examples, to demonstrat...
Article
The focus in this study is to examine the flow formation of Taylor–Couette (T–C) for some fluids exhibiting non-Newtonian properties in a region of cylindrical annulus due to the effect of imposed stresses on the periphery of the inner cylinder while the outer cylinder is hanging around inert. This tangential shear will be liable for the motion of...
Article
According to the Warburg effect, there are some significant differences between metabolisms, products and process of respirations of cancer cells and normal cells. For example, normal cells absorb oxygen and glucose and give water molecules, carbon dioxide, ATP molecules and some number of spinors; while cancer cells take glucose and give lactate,...
Article
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Many 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 malar...
Article
This work aims to assess the response of viscoelastic Kelvin–Voigt microscale beams under initial stress. The microbeam is photostimulated by the light emitted by an intense picosecond pulsed laser. The photothermal elasticity model with dual-phase lags, the plasma wave equation and Euler–Bernoulli beam theory are utilized to construct the system e...
Article
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The comprehension of inequalities in convexity is very important for fractional calculus and its effectiveness in many applied sciences. In this article, we handle a novel investigation that depends on the Hermite–Hadamard-type inequalities concerning a monotonic increasing function. The proposed methodology deals with a new class of convexity and...
Article
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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,...
Conference Paper
In this manuscript, we are concerned with finding approximate solutions to fractional PDEs by using the Daftardar-Jafari method (DJM). The presented method is considered in the Caputo-Fabrizio fractional operator (CFFO). Illustrative examples for handling the FPDEs are given. The obtained results are given to show the sample and efficient features...
Article
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Inequality theory has attracted considerable attention from scientists because it can be used in many fields. In particular, Hermite–Hadamard and Simpson inequalities based on convex functions have become a cornerstone in pure and applied mathematics. We deal with Simpson’s second-type inequalities based on coordinated convex functions in this work...
Article
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In this work, we present a modified generalized Mittag–Leffler function method (MGMLFM) and Laplace Adomian decomposition method (LADM) to get an analytic-approximate solution for nonlinear systems of partial differential equations (PDEs) of fractional-order in the Caputo derivative. We apply the MGMLFM and LADM on systems of nonlinear time-fractio...
Article
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Nanobiotechnology, joined with green science, has incredible potential for the advancement of novel and important products that benefit human health, climate, and industries. Green chemistry of materials from synthesis to diverse biomedical applications is a talk of town in today’s sustainable ideal world. Green synthesized nickel ferrites nanopart...
Article
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In this paper, a local radial basis function collocation method is proposed for the numerical solution of inverse space-wise dependent heat source problems. Multiquadric radial basis function is used for spatial discretization. The method accuracy is tested in terms of absolute root mean square and relative root mean square error norms. Numerical t...
Article
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In this paper, some Jensen- and Hardy-type inequalities for convex functions are extended by using Riemann–Liouville delta fractional integrals. Further, some Pólya–Knopp-type inequal- ities and Hardy–Hilbert-type inequality for convex functions are also proved. Moreover, some related inequalities are proved by using special kernels. Particular cas...
Article
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From point of view of two distinct various techniques accurate solutions for the thin-film ferroelectric materials equation which plays vital role in optics are implemented which represent haw utilized waves propagate through ferroelectric materials. The first one is the modified simple equation method which surrender to the balance rule and gives...