This study used particle swarm optimization (PSO) to determine the optimal values of effective design variables acting on the stress distribution around a quasi-triangular hole in an infinite orthotropic plate. These parameters were load angle, hole orientation, bluntness, fiber angle, and material properties, which were ascertained on the basis of an analytical method used by Lekhnitskii [3]. ...

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...

In this paper, the effect of interference fit on fatigue life of holed plate of mechanical joints was investigated experimentally. Fatigue tests were carried out on the holed specimens of Al-alloy 7075-T6 alloy. The interference fit process consists of force fitting a fastener into the hole with a negative clearance (diameter of the fastener is larger than of the hole) that produces beneficial ...

The main purpose of this research is portfolio optimization in Tehran securities exchange using the black hole algorithm and the Gravitational Research algorithm. We also propose an algorithm named Hybrid Algorithm which combines the two algorithms above to cover the weaknesses of these two algorithms. Finally we compare the results with the Markowitz model and choose the optimal algorithm.<br ...

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...

The electric arc furnace (EAF) is used to produce high quality steel from steel scraps. The EAF uses plasma arc to generate heat for melting scarp or direct reduced iron (DRI). The liquid metal should be drained from the tap hole. Manual tapping operation of the EAF in the hot environment around the furnace is a potentially dangerous and time consuming task for the workers. Therefore, it is ess...