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Effects of thermophoresis and thermal radiation in mixed convection three-dimensional flow of Jeffrey fluid

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Applied Mathematics and Mechanics(English Edition) 2015年第5期36卷 655-668页

作者： s.A.sHEHZAD T.HAYAT A.ALsAEDI B.ahmad Department of Mathematics Comsats Institute of Information Technology Department of Mathematics Quaid-i-Azam University Department of Mathematics Faculty of Science King Abdulaziz University

Mixed convection three-dimensional flow of Jeffrey fluid is studied in the presence of thermal radiation and thermophoresis. The relevant problems are formulated,and series solutions are presented for velocities, temperature, and concentration. Convergence of series solutions is obtained graphically and numerically. Effects of different emerging parameters on the velocities, temperature, and concentration fields are plotted and discussed.

关键词： convection formulated Jeffrey Prandtl convergent admissible illustrate relaxation stretching numerically

Effect of srCO_3 addition on the dynamic compressive strength of ZTA

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International Journal of Minerals,Metallurgy and Materials 2016年第4期23卷 481-489页

作者： Ali Arab Roslan ahmad Zainal Arifin ahmad school of Mechanical Engineering Universiti Sains Malaysia Engineering Campus structural Materials Niche Area School of Materials and Mineral Resources Engineering Universiti Sains Malaysia Engineering Campus

Ceramic parts usually experience dynamic load in armor applications. Therefore, studying the dynamic behaviors of ceramics is important. Limited data are available on the dynamic behaviors of ceramics; thus, it is helpful to predict the dynamic strength of ceramics on the basis of their mechanical properties. In this paper, the addition of srCO3 into zirconia-toughened alumina（ZTA） was demonstrated to improve the fracture toughness of ZTA due to the formation of the srAl12O19（sA6） phase. The porosity of ZTA was found to be increased by the addition of srCO3. These newly formed pores served as the nucleation sites of cracks under dynamic load; these cracks eventually coalesced to form damaged zones in the samples. Although the KIC values of the samples were improved, the dynamic strength was not enhanced because of the increase in porosity; in fact, the dynamic strength of ZTA ceramics decreased with the addition of srCO3.

关键词： ceramics strontium carbonate dynamic properties fracture toughness compressive strength

Effect of Ascorbic Acid and silicium on Photosynthesis, Antioxidant Enzyme Activity, and Fatty Acid Contents in Canola Exposure to salt stress

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Journal of Integrative Agriculture 2012年第10期11卷 1610-1620页

作者： ahmad Bybordi East Azarbaijan Research Center for Agriculture and Natural Resources

The effects of exogenous ascorbic acid and silicium on leaf fresh weigh, seed yield, photosynthesis, changes of the activities of major antioxidant enzymes, nitrate reductase activity, proline accumulation, chlorophyll content, and fatty acid composition were investigated in salt-stressed canola. A hydroponic pot experiment was conducted based on randomized complete block design, factorial arrangement was used with 16 combinations of salinity stress （0, 100, 200, and 300 mmol L-1 NaC1）, ascorbic acid （0 and 30 mmol L-1）, and silicium （2 and 4 mmol L-1 from potassium silicate） with three replicates. The results showed that salinity significantly decreased leaf area and leaf fresh weight, seed yield, photosynthesis, nitrate reductase activity, chlorophyll content, and seed protein percentage. Conversely, respiration, antioxidant enzymes activity, proline accumulation, and linolenic acid percentage increased due to salt stress. Ascorbic acid application improved photosynthesis and seed yield and mitigated antioxidant enzyme activity. In addition, nitrate reductase activity and chlorophyll a and b were positively affected by ascorbic acid. Regarding silicium application, that was found that leaf area, leaf fresh weight, seed yield and photosynthesis, ascorbate peroxidase activity, nitrate reductase activity, and chlorophyll content increased, while respiration decreased. Furthermore, silicium had not significant effect on antioxidant enzyme activity. In general, ascorbic acid and silicium were involved in the defensive mechanisms against salinity stress and it can be suggested that, ascorbic acid and silicium application had positive effect on canola growth under conditions of salt stress.

关键词： ascorbic acid salt stress canola silicium

Damped Kadomtsev–Petviashvili Equation for Weakly Dissipative solitons in Dense Relativistic Degenerate Plasmas

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Communications in Theoretical Physics 2017年第12期67卷 783-790页

作者： s.ahmad Ata-ur-Rahman s.A.Khan F.Hadi Department of Physics University of Kotli Azad Jammu and Kashmir Department of Physics Theoretical Plasma Physics Group Islami a College Peshawar (A Public Sector University) National Centre for Physics Quaid-i-Azam University Campus Department of Nuclear Engineering Kyoto University Department of Applied Physical and Material sciences University of Swat

We have investigated the properties of three-dimensional electrostatic ion solitary structures in highly dense collisional plasma composed of ultra-relativistically degenerate electrons and non-relativistic degenerate ions. In the limit of low ion-neutral collision rate, we have derived a damped Kadomtsev–Petviashvili(KP) equation using perturbation analysis. supplemented by vanishing boundary conditions, the time varying solution of damped KP equation leads to a weakly dissipative compressive soliton. The real frequency behavior and linear damping of solitary pulse due to ion-neutral collisions is discussed. In the presence of weak transverse perturbations, soliton evolution with damping parameter and plasma density is delineated pointing out the extent of propagation using typical parameters of dense plasma in the interior of white dwarfs.

关键词： dissipative solitons damped Kadomtsev–Petviashvili equation

Viscous effects on plasmoid formation from nonlinear resistive tearing growth in a Harris sheet

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Plasma science and Technology 2022年第1期24卷 18-29页

作者： Nisar ahmad Ping ZHU ahmad ALI shiyong ZENG CAs Key Laboratory of Geospace Environment and Department of Engineering and Applied Physics University of Science and Technology of ChinaHefei 230026People's Republic of China International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China Department of Engineering Physics University of Wisconsin-MadisonMadisonWisconsin 53706United States of America Pakistan Tokamak Plasma Research Institute Islamabad 44000Pakistan Department of Plasma Physics and Fusion Engineering University of Science and Technology of ChinaHefei 230026People’s Republic of China

In this work,the evolution of a highly unstable m=1 resistive tearing mode,leading to plasmoid formation in a Harris sheet,is studied in the framework of full MHD model using the Non-Ideal Magnetohydrodynamics with Rotation,Open Discussion *** the initial nonlinear growth of the primary m=1 island,the X-point develops into a secondary elongated current sheet that eventually breaks into *** distinctive viscous regimes are found for the plasmoid formation and *** the low viscosity regime(i.e.P_(r)■1),the plasmoid width increases sharply with viscosity,whereas in the viscosity dominant regime(i.e.P_(r)■1),the plasmoid size gradually decreases with *** a finding quantifies the role of viscosity in modulating the plasmoid formation process through its effects on the plasma flow and the reconnection itself.

关键词： viscosity reconnection plasmoids Prandtl number

squeezed state generation using cryogenic InP HEMT nonlinearity

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Journal of semiconductors 2023年第5期44卷 69-77页

作者： ahmad salmanogli Engineering Faculty Electrical and Electronic DepartmentCankaya UniversityAnkaraTurkey

This study focuses on generating and manipulating squeezed states with two external oscillators coupled by an InP HEMT operating at cryogenic ***,the small-signal nonlinear model of the transistor at high frequency at 5 K is analyzed using quantum theory,and the related Lagrangian is theoretically ***,the total quantum Hamiltonian of the system is derived using Legendre *** Hamiltonian of the system includes linear and nonlinear terms by which the effects on the time evolution of the states are *** main result shows that the squeezed state can be generated owing to the transistor’s nonlinearity;more importantly,it can be manipulated by some specific terms introduced in the nonlinear *** fact,the nonlinearity of the transistors induces some effects,such as capacitance,inductance,and second-order transconductance,by which the properties of the external oscillators are *** changes may lead to squeezing or manipulating the parameters related to squeezing in the *** addition,it is theoretically derived that the circuit can generate two-mode ***,second-order correlation(photon counting statistics)is studied,and the results demonstrate that the designed circuit exhibits antibunching,where the quadrature operator shows squeezing behavior.

关键词： quantum theory squeezed state cryogenic low noise amplifier InP HEMT

Thermal conductivity modeling of water containing metal oxide nanoparticles

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Journal of Central south University 2015年第3期22卷 1141-1145页

作者： ahmad Azari Persian Gulf University Faculty of Oil Gas and Petrochemical EngineeringChemical Engineering Department

The nano particles have demonstrated great potential to improve the heat transfer characteristics of heat transfer *** parameters responsible for this increase were studied. The heat transfer profile in the nanolayer region was combined with other parameters such as volume fraction, particle radius thermal conductivity of the fluid, particle and nanolayer, to formulate a thermal conductivity model. Results predicting the thermal conductivity of nanofluids using the model were compared with experimental results as well as studies by other researchers. The comparison of the results obtained for the Cu O/water and Ti O2/water nanofluids studied shows that the correlation proposed is in closest proximity in predicting the experimental results for the thermal conductivity of a nanofluid. Also, a parametric study was performed to understand how a number of factors affect the thermal conductivity of nanofluids using the developed correlation.

关键词： nanofluid effective thermal conductivity nanoparticle nanolayer modeling

Efficient Optimal Routing Algorithm Based on Reward and Penalty for Mobile Adhoc Networks

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Computers, Materials & Continua 2023年第4期75卷 1331-1351页

作者： Anubha Ravneet Preet singh Bedi Arfat ahmad Khan Mohd Anul Haq ahmad Alhussen Zamil s.Alzamil Department of Computer Applications I.K.G.Punjab Technical UniversityKapurthala144601PunjabIndia Research and Development I.K.G.Punjab Technical UniversityKapurthala144604PunjabIndia Department of Computer science College of ComputingKhon Kaen UniversityKhon Kaen40002Thailand Department of Computer science College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia Department of Computer Engineering College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia

Mobile adhoc networks have grown in prominence in recent years,and they are now utilized in a broader range of *** main challenges are related to routing techniques that are generally employed in *** Adhoc system management,on the other hand,requires further testing and improvements in terms of *** routing protocols,such as Adhoc On-Demand Distance Vector(AODV)and Dynamic source Routing(DsR),employ the hop count to calculate the distance between two *** main aim of this research work is to determine the optimum method for sending packets while also extending life time of the *** is achieved by changing the residual energy of each network ***,in this paper,various algorithms for optimal routing based on parameters like energy,distance,mobility,and the pheromone value are ***,an approach based on a reward and penalty system is given in this paper to evaluate the efficiency of the proposed algorithms under the impact of *** simulation results unveil that the reward penalty-based approach is quite effective for the selection of an optimal path for routing when the algorithms are implemented under the parameters of interest,which helps in achieving less packet drop and energy consumption of the nodes along with enhancing the network efficiency.

关键词： Routing optimization reward penalty mobility energy throughout pheromone

Video Games Localization into Arabic:Gamers’Reactions to Localizing PUBG and Free Fire

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Journal of social Computing 2023年第1期4卷 74-93页

作者： shatha Jarrah saleh Al-salman ahmad s Haider Department of English Language and Translation Applied Science Private UniversityAmman 11937Jordan MEU Research Unit Middle East UniversityAmman 11831Jordan

The Middle East and North Africa(MENA)region has an active gaming community,with Arab gamers being reliant on games produced in Europe,America,and Japan due to the lack of significant game production companies in the MENA *** study explores the gamers’reactions to the localization process of two video games,namely PUBG and Free *** data collection purposes,a five-point Likert scale questionnaire that consisted of 18 items and six constructs,namely need for subtitled games,technical aspects,language issues,language preference,attitudes to game localization,and future actions and recommendations,was designed to elicit the reactions of 112 *** analyzing the responses,the findings showed that the better the technical aspects and language issues of the games’performance,the more positive participants’attitudes to game *** study recommends that further research could be conducted on the localization of video games with different themes into Arabic.

关键词： localization video games PUBG Free Fire Audio Visual Translation(AVT)