INTRODUCTION LASIK surgery is currently the preferred procedure to correct low to moderate myopia. The aim of this study was to determine the orientation of the steepest meridian of regular astigmatism in order to determine the relative incidence of vertical, horizontal, and oblique regular astigmatism among highly myopic Egyptian patients seeking non-ablative surgical correction of the refract...

Combined radiation and natural convection within the annular region of two infinitely long horizontal concentric cylinders are investigated numerically in this research. Radial and tangential radiation effects ate considered using Milne-Eddington approximation for a two-dimensional radiative transfer. The basic conservation equations are discretized with the finite volume method and SIMPLER alg...

In this paper natural convection heat transfer within a two-dimensional, horizontal, concentric cam shape cylinders that is partially filled with a fluid saturated porous medium has been investigated. both cylinder are kept at constant and uniform temperatures with the outer cylinder being subjected relatively lower than the inner one. In addition the forchheimer and brinkman effect are taken i...

A quasi three-dimensional numerical model is developed to study vortex-induced vibration (VIV) of two tandem flexible circular cylinders. In this model, the whole cylinder is divided into many sections along its length. The hydrodynamics of each section are represented by the solution of the two-dimensional Navier-Stokes equations. The dynamic response of the flexible cylinder is predicted by t...

in this research, static stresses analysis of boron nitride nano - tube reinforced composite (bnntrc) cylinder made of poly - vinylidene fluoride (pvdf) subjected to non - axisymmetric thermo - mechanical loads and applied voltage is developed. the surrounded elastic medium is modelled by pasternak foundation. composite structure is modeled based on piezoelectric fiber reinforced composite (pfr...

for the characteristics of horizontal fractures in shallow low-permeability oil layers after hydraulic fracturing in multilayer reservoirs, horizontal fractures are taken equivalent to an elliptical cylinder with the reservoir thickness using the equivalent permeability model; then, upon the elliptic seepage theory, the seepage field which has led by a vertical well with horizontal fractures is...