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991.
992.
Kyungwoo Lee 《International Journal of Non》2002,37(3):439-443
Large deflection of cantilever beams made of Ludwick type material subjected to a combined loading consisting of a uniformly distributed load and one vertical concentrated load at the free end was investigated. Governing equation was derived by using the shearing force formulation instead of the bending moment formulation because in the case of large deflected member, the shearing force formulation possesses some computational advantages over the bending moment formulation. Since the problem involves both geometrical and material non-linearities, the governing equation is complicated non-linear differential equation, which would in general require numerical solutions to determine the large deflection for a given loading. Numerical solution was obtained by using Butcher's fifth order Runge-Kutta method and are presented in a tabulated form. 相似文献
993.
On the basis of the expansion of the hard aperture function into a finite sum of complex Gaussian functions, the approximate analytical expression of Laguerre-Gaussian beams passing through an annular apertured paraxial ABCD optical system is derived. Meanwhile, the corresponding closed-forms for the unapertured or circular apertured or circular black screen cases have also been given. Numerical examples are given to illustrate the propagation characteristics of Laguerre-Gaussian beams. 相似文献
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995.
We investigate incoherently coupled bright-bright soliton pairs in photorefractive crystals under steady-state condition in both one and two transverse dimensions. The novel numerical scheme according to the Crank-Nicholson method generalized in three dimensions accompanied by the central difference method was used to solve the coupled wave and potential equations in order to find soliton solution and pairs distribution. Simulation of propagation is performed numerically and show that the presence of both components is required for stable propagation. This simulation approach demonstrates beams evolution after decoupling clearly. 相似文献
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1 Introduction Laserbeamswithamplitudemodulations(AMs)andphasefluctuations (PFs) proposedbytheLawrence LivermoreNationalLaboratory (LLNL)isatypicalphysicalmodelforhigh powerlasers[1] .Inhigh powerlasersystems,suchaslargeNd∶glasslaserfusiondrivers,high powerla… 相似文献
1000.
The finite element (FE) method is employed to analyse the response of clamped sandwich beams subject to shock loadings. Pressure versus time histories representative of shock loadings are applied uniformly to the outer face of the sandwich beam; an impulse applied uniformly to the outer face of the sandwich beam is shown to model adequately shock loadings. Material elasticity and strain hardening representative of structural steels have only a minor effect upon the beam response. Further, the magnitude of the compressive strength of the core has only a limited influence upon the dynamic response of the sandwich beam for the representative range of core strengths considered. The FE results for the deflections and structural response time agree well with the rigid ideally-plastic analytical predictions of Fleck and Deshpande (J. Appl. Mech. (2003), in press). 相似文献