In this paper, we present a comparative numerical analysis to determine the refractive index of photonic crystal fibers (PCFs) by using FDFD method and used the results to evaluate the confinement losses of PCFs by considering the effects of air-hole rings in the cladding. It is shown that by increasing the wavelength, the imaginary part of refraction index rises, resulting in increase of conf...

The aim of our study is to analyze the impact of insertion holes in the middle of obstacles on the flow around a surface-mounted cube, In order to do this; we studied four configurations of obstacles in a channel with a Reynods number based on obstacle height ReH = 40000. The hexahedral structured meshes were used to solve the fluid dynamics equations .The finite volume method are employed to s...

Stress concentration factors have been examined in a functionally graded material (FGM) plate with central holes in different shapes in this essay. The material properties change along the thickness of plate. ABAQUS software has been utilized for modeling of problem in which subroutine of ABAQUS sub-program was used for modeling of the targeted material. The considering shapes for hole in plate...

A two-stage methodology is presented for enhancing the process of assigning quality problems to quality improvement teams in industrial firms. The method advances the decision support system of the quality improvement process by grouping the related quality problems in two steps:. First, a soft grouping is performed using association rules as a data mining technique, and then, resulted groups a...

oxides of nitrogen are the major emission from a diesel engine. it is due to heterogeneous diffusion combustion system with fuel-rich regions, which produce high local temperature around the periphery of the spray where high formation rate of no is promoted. various techniques are therefore employed to reduce the nox emission like egr, scr, etc. in this present work a rotating injector is a tec...

tube hydroforming (thf) process is used to produce the complex components from the initial cylindrical tubes. in this paper, t- shape component was formed using a tube hydroforming machine and the residual stresses of hydroformed tube was determined by hole drilling method. subsequently, the thickness distribution and residual stresses of final tube were investigated using experimental and fini...

The mechanisms determining the growth of high-quality monolayer and bilayer graphene on Cu using chemical vapor deposition (CVD) were investigated. It is shown that graphene growth on Cu is not only determined by the process parameters during growth, but also substantially influenced by the quality of Cu substrate and how the Cu substrate is pretreated. It is found that the micro-topography of ...

in this study, behavior of pin-loaded glass fiber reinforced with polyethylene laminated composites with different stacking sequence and different dimensions has been observed experimentally and stress analysis was performed using ansys software. the aim is to investigate stresses, failure strength and failure mode of composite laminates containing a pin loaded hole when the material exhibits l...