This paper discusses the use of wave based prediction methods for the analysis of steady-state interior acoustic problems. Conventional element based prediction methods, such as the Finite Element Method (FEM), are commonly used, but are restricted to low-frequency applications. The Wave Based Method (WBM) is an alternative deterministic technique which is based on the indirect Trefftz approach...

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...

The Rayleigh-Ritz method finds the stationary values, called Ritz values, of the Rayleigh quotient on a given trial subspace as approximations to eigenvalues of a Hermitian operator A. If the trial subspace is A-invariant, the Ritz values are exactly some of the eigenvalues of A. Given two subspaces X and Y of the same finite dimension, such that X is A-invariant, the absolute changes in the Ri...

in this paper, a three-dimensional finite element model has been developed to simulate the laser-tig hybrid welding (hlaw) of stainless steel 1.4418 with thickness of 4 mm. transient temperature profile and dimensions of the fusion zone and heat affected zone (haz) during welding process are calculatedusing finite element method (fem) and were solved in the abaqus/standard software.the heat sou...

introduction: because of the importance of vertebral compressive fracture (vcf) role in increasing the patients’ death rate and reducing their quality of life, many studies have been conducted for a noninvasive prediction of vertebral compressive strength based on bone mineral density (bmd) determination and recently finite element analysis. in this study, qct-voxel based nonlinear finite eleme...

Sound pathways in the enclosures of small earphones are very narrow. In such narrow pathways, the speed of sound propagation and the phase of sound waves change because of the air viscosity. We have developed a new finite element method that includes the effects of damping due to air viscosity for modeling the sound pathway. This method is developed as an extension of the existing finite elemen...