Multiscale computational approach that combines different methods to study laser ablation phenomenon is presented. The methods include the molecular dynamics (MD) breathing sphere model for simulation of the initial stage of laser ablation, a combined MD finite element method (FEM) approach for simulation of propagation of the laser-induced pressure waves out from the MD computational cell, and...

In this research work, investigations are carried out on Continuous Wave (CW) Nd:YAG laser welding system after preliminary experimentation to understand the influencing parameters associated with laser welding of AISI 304. The experimental procedure involves a series of laser welding trials on AISI 304 stainless steel sheets with various combinations of process parameters like beam power, beam...

Terrestrial laser scanning technology (TLS) is a new technique for quickly getting three-dimensional information. In this paper we research the health assessment of concrete structures with a Finite Element Method (FEM) model based on TLS. The goal focuses on the benefits of 3D TLS in the generation and calibration of FEM models, in order to build a convenient, efficient and intelligent model w...

An inflammatory pseudotumour of the lung in an achondroplastic woman is described. The occurrence of both conditions in the same patient probably represents a coincidental finding. However, recurrent pulmonary infections, as frequently seen in achondroplasia, may be relevant, because a history of antecedent infection is noted in one third of cases of inflammatory pseudotumours. Despite extensiv...

laser forming is a modern process which is mainly used for forming metals. different lasers are used in this regard that includes nd: yag and co2. in this study, forming bi-layer sheets of aluminum/ceramic by laser was investigated. furthermore, effect of uniform and gaussian heat flux distribution in different power, velocity, and beam diameters on bending angle was studied. fem simulation ind...

read with interest the article of Dr Asilian and coauthors entitled “Comparison between the efficacy of Q-Switched 1064-nm Nd:YAG laser and Fraxel CO2 laser on improvement of atrophic facial acne scars” in this journal. In this article the authors concluded a better efficacy for fractional CO2 laser in comparison with 1064-nm Q-switched NdYag laser.1 Treatment of the atrophic acne scars is a re...

Expertise of packaging for optoelectronic components requires the solution of optical, mechanical and electrical problems in the same way. The purpose of this study is to present three-dimensional simulations using finite element method (FEM) of thermomechanical stresses and strains in transmitter Laser modules induced by Nd:YAG crystal Laser welds on main sub-assembly Laser submount. Non-linea...

Laser beam welding (LBW) is one of the most important manufacturing processes used for joining of materials. It is also a remarkably complicated, nonlinear operation involving extremely high temperatures. Since its invention more than two decades ago, laser beam welding has been more of an art than a science. Laser welding of austenitic stainless steel AISI 304 the candidate material of this re...

Accelerator Test Facility at Brookhaven National Laboratory (BNL ATF) operates with 5 MeV photocathode gun and 70 MeV linac for different range of experiments with a few picoseconds and a few micrometers emittance electron bunch. Many conducted experiments require beam with good spatial resolution and short length as well. NdYaG laser pulse turns to the electron bunch in the gun with space char...