nowadays, one of the main problems encountered in minimally invasive surgery and telesurgery is the detection of arteries in tissue. in this study, for the first time, tactile detection of an artery in tissue and distinguishing it from the tumor has been modeled by finite element method. in this modeling, three 2d models of tissue have been created: tissue, tissue including a tumor, and tissue ...

a new approach is proposed to model a crack in orthotropic composite media using the extended finite element method (xfem). the xfem uses the concept of partition of unity in addition to meshless basic idea of approximating a field variable by its values at a set of surrounding nodes. as a result, higher order approximations can be designed with the same total number of degrees of freedom. in t...

some numerical and experimental investigations are made on the performance of five different hyperelastic constitutive models (second order polynomial, yeoh, arruda-boyce, ogden and marlow) in tension and compressionmodes. first, the results of the tensile and compression tests on a rubber sample were used to determine the parameters of the models by curve fitting methods. next, by using an alg...

.hot metal gas forming of tubes can be used in various industries such as automotive and aerospace industries. in this process tube is formed at elevated temperatures, by using gas instead of fluid pressure. lower required pressure and low power are its advantages in comparison to hydroforming process. in this paper, a hot metal gas bulging process of an aluminum alloy tube has been investigate...

in this article, finite element method and ale formulation were used to numerically simulate impact of low-velocity specific projectiles with water surface. for the simulation, ls-dyna finite element code was used. material models which were used to express behavior of air and water included null material model. for the projectile, plastic-kinematics material model was applied. mie-gruneisen eq...

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...

introduction: mandibular first molar is the most important tooth with complicated morphology. in finite element (fe) studies, investigators usually prefer to model anterior teeth with a simple and single straight root; it makes the results deviate from the actual case. the most complicated and time-consuming step in fe studies is modeling of the desired tooth, thus this study was performed to e...

In the present study, the three-dimensional elastic discrete element method (DEM) and the elastic finite element method (FEM) analysis were, respectively, applied to the randomly distributed identical spheres as a granular target and to the cylindrical projectiles in order to clarify dynamic response during penetration. In the target, it was found that highly densified region was formed just ah...