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Chinese Physics Letters 2011年第7期28卷 202-205页

作者： t.Hayat M.Mus.afa s.Obaidat Department of Mathematics Quaid-I-Azam University 45320Islamabad 44000Pakistan Department of Mathematics College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia Res.arch Centre for Modeling and simulation National University of Sciences and TechnologySector H-12IslamabadPakistan

Magnetohydrodynamic(MHD)mixed convection s.agnation-point flow and heat transfer of power-law fluids towards.a stretching surface is *** homotopy analysis method(HAM)is used in finding the series solution for a nonlinear *** form solutions for velocity and temperature fields.are presented in the limiting *** results.are *** is found that velocity and temperature are decreasing functions of power law *** computations for shear stress coefficient and local Nusselt number are *** present results.are also compared with the existing numerical solution in a limiting sense.

关键词： problem limiting stretching

Dynamic s.abilization of plas.a ins.ability

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High Power Laser science and Engineering 2019年第1期7卷 17-26页

作者： s.Kawata t.Karino Y.J.Gu Graduate school of Engineering Utsunomiya University Institute of Physics of the AsCR ELI-Beamlines Institute of Plas.a Physics of the CAs

the paper presents.a review of dynamic s.abilization mechanisms for plas.a ins.abilities. One of the dynamic s.abilization mechanisms for plas.a ins.ability was proposed in the paper [Kawata, Phys. Plas.as 19, 024503(2012)],based on a perturbation phase control. In general, ins.abilities emerge from the perturbations. Normally the perturbation phase is unknown, and so the ins.ability growth rate is discussed. However, if the perturbation phase is known, the ins.ability growth can be controlled by a superimposition of perturbations imposed actively. Based on this mechanism we present the application results of the dynamic s.abilization mechanism to the Rayleigh–taylor ins.ability(RtI) and to the filamentation ins.ability as typical examples in this paper. On the other hand, in the paper [Boris, Comments Plas.a Phys. Control. Fusion 3, 1(1977)] another mechanism was proposed to s.abilize RtI, and was realized by the pulse train or the laser intensity modulation in laser inertial fusion [Betti et al., Phys. Rev. Lett. 71, 3131(1993)]. In this latter mechanism, an oscillating strong force is.applied to modify the basic equation, and consequently the new s.abilization window is created. Originally the latter was proposed by Kapitza. We review the two s.abilization mechanisms, and present the application results of the former dynamic s.abilization mechanism.

关键词： dynamic ins.ability s.abilization filamentation ins.ability plas.a ins.ability Rayleigh-taylor ins.ability s.abilization of ins.ability

Unsteady MHD flow over exponentially stretching sheet with slip conditions

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Applied Mathematics.and Mechanics(English Edition) 2016年第2期37卷 193-208页

作者： t.HAYAt A.s.aFIQ A.ALsAEDI s.a.s.aHZAD Department of Mathematics Quaid-i-Azam University Nonlinear Analysis.and Applied Mathematics (NAAM) Res.arch Group Department of Mathematics Faculty of Science King Abdulaziz University Department of Mathematics Comsats Institute of Information Technology

the present paper examines the hydromagnetic three-dimensional flow in- duced by a stretched surface. An incompressible material saturates the porous medium. Velocity and thermal slip boundary conditions.are considered. suitable transformations.are used to obtain the nonlinear ordinary differential equations. series solutions of the resulting systems.are constructed. the effects of various pertinent parameters on the axial velocity and temperature distributions.are analyzed graphically. the skin friction and the Nusselt number are computed numerically and graphically.

关键词： three-dimensional flow velocity and thermal slip conditions porous medium

Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control theory and technology 2024年第2期22卷 326-341页

作者： t.R.Dil Kumar s.J.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

the ball and plate system is.an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. the system comprises.a ball and plate mechanism and a rotary servo unit. the ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. the nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resis.ance between the ball and the plate. the simplified nonlinear model of the system is obtained with suitable assumptions. the model is linearized around the operating point using the Jacobian. the validity of the developed models is investigated through correlation function analysis. the open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is.analyzed in the MAtLAB/simulink platform. since the open-loop system is uns.able, the experimental validation of the model is performed with a double-loop PsO (particle s.arm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle s.arm optimization(PsO) PsO PID controller

COORDINAtING A tWO-ECHELON sUPPLY CHAIN tHROUGH DIFFERENt CONtRACts UNDER PRICE AND PROMOtIONAL EFFORt-DEPENDENt DEMAND

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Journal of systems science and systems Engineering 2013年第3期22卷 295-318页

作者： B.C.GIRI s.BARDHAN t.MAItI Department of Mathematics Jadavpur UniversityIndia

Retail price and promotional effort are two important parameters on which demand of a commodity largely depends. this paper develops.and analyzes.a two-echelon supply chain where market demand depends on both retail price and sales effort. the centralized model is studied as the benchmark case, and the wholesale price-only contract is studied as the base case in which each entity tries to maximize its individual profit. Different contract mechanisms.are implemented to outperform the base case in terms of both total chain＇s.as well as individual profits. Comparisons.among the coordinating contracts.are provided so that any entity may choose the better one from available contracts.after the contract parameters.are negotiated. the model is extensively examined through a numerical example.

关键词： Price and effort-dependent demand wholesale price-only contract wholesale price discount revenue s.aring profit s.aring two-part tariff

Exact solutions in generalized Oldroyd-B fluid

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Applied Mathematics.and Mechanics(English Edition) 2012年第4期33卷 411-426页

作者： t. HAYAt s. ZAIB s. AsGHAR A. A. HENDI Department of Mathematics Quaid-i-Azam University Department of Mathematics Comsats Institute of Information Technology Department of Physics Faculty of Science King Saud University

this investigation deals with the influence of slip condition on the magne- tohydrodynamic （MHD） and rotating flow of a generalized Oldroyd-B （G. Oldroyd-B） fluid occupying a porous s.ace. FractionM calculus.approach is used in the mathematical modeling. three illustrative examples induced by plate oscillations.and periodic pressure gradient are considered, and the exact solutions in each case are derived. Comparison is provided between the results of slip and no-slip conditions. the influence of slip is highlighted on the velocity profile by displaying graphs.

关键词： slip condition exact solution fractional calculus

Optimizing pulsed current gas tungsten arc welding parameters of AA6061 aluminium alloy using Hooke and Jeeves.algorithm

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中国有色金属学会会刊：英文版 2008年第5期18卷 1028-1036页

作者： s.BABU t.sENtHIL KUMAR V.BALAsUBRAMANIAN Centre for Materials Joining Res.arch (CEMAJOR) Department of Manufacturing EngineeringAnnamalai UniversityAnnamalai Nagar-608 002Tamil NaduIndia Department of Automobile technology Bharathidasan Institute of TechnologyAnna UniversityTiruchirappalli-620 016Tamil NaduIndia

though the preferred welding process to weld aluminium alloy is frequently cons.ant current gas tungsten arc welding (CCGtAW),it resulted in grain coarsening at the fusion zone and heat affected zone(HAZ).Hence,pulsed current gas tungsten arc welding(PCGtAW) was performed,to yield finer fusion zone grains,which leads to higher strength of AA6061 (Al-Mg-si) aluminium alloy *** order to determine the most influential control factors which will yield minimum fusion zone grain size and maximum tensile strength of the joints,the traditional Hooke and Jeeves pattern s.arch method was *** experiments were carried out based on central composite design with 31 runs.and an algorithm was developed to optimize the fusion zone grain size and the tensile strength of pulsed current gas tungsten arc welded AA6061 aluminium alloy *** results indicate that the peak current (Ip) and base current (IB) are the most significant parameters,to decide the fusion zone grain size and the tensile strength of the AA6061 aluminum alloy joints.

关键词：脉冲电流钨电极惰性气体保护焊铝合金颗粒尺寸

A theoretical test of the Geostrophic Momentum Approximation

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Advances in Atmospheric sciences 1992年第2期9卷 251-255页

作者： t.s.s.assova Institute of Meteorology and Hydrology Bulgarian Academy of Sciences Sofia previously developed model of a 2-dimensional air flow with constant horizontal shear is used to estimeate the accuracy of the geostrophic momentum approximation by comparison of exact solutions when exist with approximate ones.

A previously developed model of a 2-dimensional air flow with cons.ant horizontal shear is used to estimeate the accuracy of the geostrophic momentum approximation by comparison of exact solutions when exist with appr... 详细信息

关键词： Approximation exact approximate momentum thank preserved formulated ordina symmetry assumed

Constraining the temperature-density Relation of the Inter-galactic Medium from Analytically Modeling LyαForest Absorbers

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Res.arch in Astronomy and Astrophysics 2023年第4期23卷 72-84页

作者： Li Yang Zheng Zheng t.-s.Kim s.anghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China school of Astronomy and s.ace sciences University of Chinese Academy of SciencesBeijing 100049China Department of Physics.and Astronomy University of Utah115 S 1400 ESalt Lake CityUT 84112USA Department of Astronomy University of Wisconsin475 North Charter StreetMadisonWI 53706USA

the absorption by neutral hydrogen in the intergalactic medium(IGM)produces the Lya forest in the spectra of *** Lya forest absorbers have a broad distribution of neutral hydrogen column density N_(HⅠ) and Doppler b *** narrowest Lya absorption lines(of lowest b)with neutral hydrogen column density above~10^(13)cm^(-2) are dominated by thermal broadening,which can be used to constrain the thermal s.ate of the *** we constrain the temperature-density relation t=t0(ρ/■)γ^(-1) of the IGM at 1.6sing N_(HⅠ) and b parameters measured from 24 high-resolution and high-signal-to-noise quasar spectra and by employing an analytic model to model the N_(HⅠ) -dependent low-b cutoff in the b *** each N_(HⅠ) bin,the b cutoff is estimated using two methods,one non-parametric method from computing the cumulative b distribution and a parametric method from fitting the full b *** find that the IGM temperature t0 at the mean gas densityρshows.a peak of~1.5×10^(4) K at z~*** redshift higher than this,the indexγapproximately remains cons.ant,and it s.arts to increase toward lower *** evolution in both parameters is in good agreement with constraints from completely different approaches,which signals that HeⅡreionization completes.around z~3.

关键词： (galaxies:)intergalactic medium-(galaxies:)quasars absorption lines-radiation mechanisms thermal

tEsts ON stRUCtURALLY DEFICIENt RC s.aBs stRENGtHENED WItH FIBRE REINFORCED POLYMER (FRP) COMPOsItEs

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工业建筑 2004年第Z1期34卷 -页

作者： s.t. smith Centre for Built Infrastructure Res.arch Faculty of Engineering University of technology Sydney PO Box 123 Broadway NSW 2007 Australia

［1］Arduini, M., Nanni, A. and Romagnolo, M. (2004) "Performance of one-way reinforced concrete s.abs with externally bonded fiber-reinforced polymer strengthening", ACI structural Journal, Vol.101, No. 2, pp. 193-201.［2］As 1012 Methods of testing Concrete, s.andards.australia, sydney, Australia.［3］As1391 (1991)Methods for tensile testing of Metals, s.andards.australia, sydney, Australia.［4］As3600 (2001) Concrete structures, s.andards.australia, sydney, Australia.［5］As/NZs4671 (2001) steel Reinforcing Materials, s.andards.australia, sydney, Australia.［6］Lam, L. and teng, J.G. (2001) “strength of RC cantilever s.abs bonded with GFRP strips”,Journal of Composites for Construction, AsCE, Vol. 5, No. 4, pp. 221-227.［7］seim, W., Horman, M. Karbhari, V. and seible, F. (2001) “External FRP poststrengthening of s.aled concrete s.abs”, Journal of Composites for Construction, AsCE, Vol. 5, No. 2, pp. 67-75.［8］smith, s.t. and Gilbert, R.I. (2003) “tests on RC s.abs reinforced with 500 MPa welded wire fabric”, Proceedings (CD-ROM), Concrete in the 3rd Millennium, CIA 2003, 21st Biennial Conference, Concrete Institute of Australia (CIA), Bris.ane, Australia, 17-19 July.［9］teng, J.G., Lam, L, Chan, W. and Wang, J. (2000) “Retrofitting of deficient RC cantilever s.abs using GFRP strips”, Journal of Composites for Construction, AsCE, Vol. 4, No. 2, pp. 75-84.［10］teng, J.G., Chen, J.F., smith, s.t. and Lam, L. (2002) FRP-strengthened RC structures, John Wiley & sons, Chichester, West sussex, U.K., 245 pp.［11］teng, J.G., smith, s.t., Yao, J. and Chen, J.F. (2003) “Intermediate crack induced debonding in RC beams.and s.abs”, Construction and Building Materials, Vol. 17, No. 6-7, pp.

关键词： steel reinforcement reinforced concrete reinforced polymer