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Semi-analytical and numerical simulations of the modified Benjamin-Bona-Mahony model

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Journal of Ocean Engineering and Science 2022年第3期7卷 264-271页

作者： Mostafa M.A.Khater samira.salama Department of Mathematics Faculty of ScienceJiangsu UniversityZhenjiang212013China Department of Mathematics Obour High Institute For Engineering and TechnologyCairo11828Egypt Division of Biochemistry Department of PharmacologyCollege of PharmacyTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia

In this article,semi-analytical and numerical simulations of the well-known modified Benjamin-Bona-Mahony(mBBM)equation are *** study targets to check the accuracy of the obtained analytical solutions of the mBBM model that have been obtained in[1]through three recent analytical schemes(extended simplest equation(ESE)method,modified kudryashov(mKud)method,and SechTanh(ST)expansion method).The considered model describes the propagation of long waves in the nonlinear dispersive media in a visual *** Homotopy iteration(HI)method,exponential cubic-B-spline(ECBS)method,and trigonometric-quantic-B-spline(TQBS)method are employed to construct novel semi-analytical and accurate numerical *** obtained solutions’accuracy has been checked through some different types of two-dimensional graphs.

关键词： Modified Benjamin-Bona-Mahony equation Approximate solutions

Lie group analysis for thermophoretic and radiative augmentation of heat and mass transfer in a Brinkman-Darcy flow over a flat surface with heat generation

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Acta Mechanica Sinica 2011年第4期27卷 531-540页

作者： Faiza A.salama Department of Mathematics Faculty of ScienceSuez Canal UniversityEgypt

A boundary layer analysis is presented to investigate numerically the effects of radiation, thermophoresis and the dimensionless heat generation or absorption on hydromagnetic flow with heat and mass transfer over a flat surface in a porous medium. The boundary layer equations are transformed to non-linear ordinary differential equations using scaling group of transformations and they are solved numerically by using the fourth order Runge-Kutta method with shooting technique for some values of physical parameters. Comparisons with previously published work are performed and the results are found to be in very good agreement. Many results are obtained and a representative set is displayed graphically to illustrate the influence of the various parameters on the dimensionless velocity, temperature and concentration profiles as well as the local skin-friction coefficient, wall heat transfer, particle deposition rate and wall thermophoretic deposition velocity. The results show that the magnetic field induces acceleration of the flow, rather than deceleration （as in classical magnetohydrodynamics （MHD） boundary layer flow） but to reduce temperature and increase concentration of particles in boundary layer. Also, there is a strong dependency of the concentration in the boundary layer on both the Schmidt number and mass transfer parameter.

关键词： Lie group analysis Brinkman-Darcy flowBoundary layer Heat and mass transfer

Integer quantum Hall effect in Kekulé-patterned graphene

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Chinese Physics B 2022年第1期31卷 553-560页

作者： Yawar Mohammadi samira Bahrami Department of Physics Farhangian UniversityTehranIran

Y-shaped Kekulébond textures in a honeycomb lattice on a graphene-copper superlattice have recently been experimentally *** this paper,the effects of such a bond modulation on the transport coefficients of Kekulé-patterned graphene are investigated in the presence of a perpendicular magnetic *** expressions are derived for the Hall and longitudinal conductivities using the Kubo *** is found that the Y-shaped Kekulébond texture lifts the valley degeneracy of all Landau levels except that of the zero mode,leading to additional plateaus in the Hall conductivity accompanied by a split of the corresponding peaks in the longitudinal ***,the Hall conductivity is quantized as±ne^(2)/h for n=2,4,6,8,10,...,excluding some plateaus that disappear due to the complete overlap of the Landau levels of different *** results also suggest that DC Hall conductivity measurements will allow us to determine the Kekulébond texture amplitude.

关键词： AAA-stacked trilayer graphene integer quantum Hall effect Kubo formula Hall conductivity

Effect of thermal conductivity on heat transfer for a power-law non-Newtonian fluid over a continuous stretched surface with various injection parameters

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Applied Mathematics and Mechanics(English Edition) 2010年第8期31卷 963-968页

作者： F.A.salama Department of Mathematics Faculty of Science Suez Canal University

The two-dimensional non-Newtonian steady flow on a power-law stretched surface with suction or injection is studied. Thermal conductivity is assumed to vary as a linear function of temperature. The transformed governing equations in the present study are solved numerically using the Runge-Kutta method. Through a comparison, results for a special case of the problem show excellent agreement with those in a previous work. Two cases are considered, one corresponding to a cooled surface temperature and the other to a uniform surface temperature. Numerical results show that the thermal conductivity variation parameter, the injection parameter, and the power-law index have significant influences on the temperature profiles and the Nusselt number.

关键词： non-Newtonian fluid thermal conductivity power-law fluid heat transfer

Parametric Estimation of Interconnected Nonlinear Systems Described by Input-output Mathematical Models

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International Journal of Automation and computing 2016年第4期13卷 364-381页

作者： Mourad Elloumi samira Kamoun Laboratory of Sciences and Techniques of Automatic Control & Computer Engineering National Engineering School of Sfax (ENIS) University of Sfax Tunisia B.P. 1173 3038 Sfax Tunisia

In this paper, two types of mathematical models are developed to describe the dynamics of large-scale nonlinear systems, which are composed of several interconnected nonlinear subsystems. Each subsystem can be described by an input-output nonlinear discrete-time mathematical model, with unknown, but constant or slowly time-varying parameters. Then, two recursive estimation methods are used to solve the parametric estimation problem for the considered class of the interconnected nonlinear systems. These methods are based on the recursive least squares techniques and the prediction error method. Convergence analysis is provided using the hyper-stability and positivity method and the differential equation approach. A numerical simulation example of the parametric estimation of a stochastic interconnected nonlinear hydraulic system is treated.

关键词： Large-scale nonlinear systems interconnected nonlinear systems deterministic systems stochastic systems input-outputmathematical models parametric estimation algorithm convergence analysis.

Robust Self-tuning Control Based on Discrete-time Sliding Mode for Auto-regressive Mathematical Model in the Presence of Unmodelled Dynamics

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International Journal of Automation and computing 2016年第3期13卷 277-284页

作者： Nabiha Touijer samira Kamoun Laboratory of Sciences and Techniques of Automatic Control and Computer Engineering (Lab-STA) National School of Engineering of SfaxUniversity of Sfax

In this paper, we propose a new robust selfbtuning control, called the generalized minimum variance a/-equivalent self- tuning control （GMVSTC-a/） for the linear timevarying （LTV） systems, which can be described by the discrete-time auto-regressive exogenous （ARX） mathematical model in the presence of unmodelled dynamics. The estimation of the parameters contained in this mathematical model is made on the basis of the proposed modified recursive least squares （m-RLS） parametric estimation algorithm with dead zone and forgetting factor. The stability analysis of the proposed parametric estimation algorithm m-RLS is treated on the basis of a Lyapunov function. A numerical simulation example is used to prove the performances and the effectiveness of the explicit scheme of the proposed robust self-tuning control GMVSTC-a/.

关键词： Discrete-time systems parametric uncertainty robust estimation robust self-tuning control sliding mode control sta-bility.

Green,mild and efficient bromination of aromatic compounds by HBr promoted by trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxolane in water as a solvent

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Chinese Chemical Letters 2012年第4期23卷 387-390页

作者： Kaveh Khosravi samira Kazemi Department of Chemistry Faculty of ScienceUniversity of Arak Department of Chemistry Shahr-e-Rey branchIslamic Azad University

A combination of HBr and trans-3,5-dihydroperoxy-3,5-dimethyl-1,2-dioxolane as anew and powerful oxidant was found effective for facile brotnination of different aromatic compounds at room temperature in water as a green *** reaction conditions,high selectivity and yield,high reaction rate and non-toxicity are some of the major advantages of this synthetic protocol.

关键词： Trans-3 5-dihydroperoxy-3 5-dimethyl-1 2-dioxolane HBr Bromination Anilines Phenoles

Cerium(Ⅳ)oxide nanocomposites:Catalytic properties and industrial application

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Journal of Rare Earths 2021年第2期39卷 129-139页

作者： samira Bagheri Ibrahim Khalil Nurhidayatullaili Muhd Julkapli Nanotechnology and Catalysis Research Centre(NANOCAT) Institute for Advanced StudiesLevel 3Block AUniversity of Malaya50603 Kuala LumpurMalaysia

This review article provides a new insight on the application of cerium oxide(CeO_(2))-metal oxide nanocomposites as catalyst with enhanced reducibility and improved oxygen(O_(2))storage capacity,especially in the varying chemical reaction processes including combustion,oxidation,epoxidation and *** CeO_(2)-metal oxide interaction plays an important role in controlling particle size,O_(2) availability and coke resistance properties of the *** metal oxide-CeO_(2) interaction also assists in generating small and highly dispersed particles,resists sintering of catalyst particles during the catalysis process,and consequently improves the O_(2) availability of the ***,CeO_(2) not only provides an active support to heterogeneous catalyst,but also creates a new active site at the metal-support interface to produce stronger nanoparticle bonding through the surface O_(2) *** consequently produces a heterogeneous catalytic system with promising reaction rate and catalytic stability in many industrial applications such as CO_(2) hydrogenation,CO oxidatio n,biodiesel productio n,gas reduction,photocatalytic and methane steam reforming.

关键词： Interface Composition Synergistic effect Active species Physiochemical Rare earths

Meeting peak electricity demand through combinatorial reverse auctioning of renewable energy

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Journal of Modern Power Systems and Clean Energy 2018年第1期6卷 73-84页

作者： Shubhashis Kumar SHIL samira SADAOUI Department of Computer Science University of Regina

The option of organizing E-auctions to purchase electricity required for anticipated peak load period is a new one for utility *** meet the extra demand load,we develop electricity combinatorial reverse auction(CRA)for the purpose of procuring power from diverse energy *** this new,smart electricity market,suppliers of different scales can participate,and homeowners may even take an active *** our CRA,an item,which is subject to several trading constraints,denotes a time slot that has two conflicting attributes,electricity quantity and *** secure electricity,we design our auction with two bidding rounds:round one is exclusively for variable energy,and round two allows storage and nonintermittent renewable energy to bid on the remaining *** electricity auction leads to a complex winner determination(WD)task that we represent as a resource procurement optimization *** solve this problem using multi-objective genetic algorithms in order to find the trade-off solution that best lowers the price and increases the *** solution consists of multiple winning suppliers,their prices,quantities and *** validate our WD approach based on large-scale simulated *** first assess the time-efficiency of our WD method,and we then compare it to well-known heuristic and exact WD *** order to gain an exact idea about the accuracy of WD,we implement two famous exact algorithms for our constrained combinatorial procurement problem.

关键词： Renewable energy auctions Combinatorial reverse auctions Electricity auctions Retail markets Winner determination Genetic algorithms Multi-objective optimization