Sharif Digital Repository

Soft tissue needle insertion characterization has been a focus of many medical and biomedical recent studies. In this study the constrained prostate soft tissue deformation through a finite element model is evaluated. The study considers a sensitivity analysis of the target reaching error with respect to the mechanical, insertion and anatomical parameters in presence of the kinematics constraint on the tissue. The needle insertion into the soft tissue is simulated using the proposed Finite Element Method (FEM). Based on acquired results, the insertion of needle induces a considerable rotation of the prostate tissue due to its specific kinematics and support structure. Such rotation can... 

Natural convection in a porous enclosure in the presence of thermal dispersion is investigated. The Fourier–Galerkin (FG) spectral element method is adapted to solve the coupled equations of Darcy’s flow and heat transfer with a full velocity-dependent dispersion tensor, employing the stream function formulation. A sound implementation of the FG method is developed to obtain accurate solutions within affordable computational costs. In the spectral space, the stream function is expressed analytically in terms of temperature, and the spectral system is solved using temperature as the primary unknown. The FG method is compared to finite element solutions obtained using an in-house code... 

Recently, remote sensing considered as important tool in studies of water quality issues. The Aras River flows across a transboundary basin in northern Iran. In this study, the aim is to model the water quality parameters (WQPs) using remote sensing and an artificial neural network (ANN), which is a new method proposed to find WQPs based on multivariate regression approaches. The relationship between WQPs and digital data from the Sentinel-2 satellite was determined to estimate and map the WQPs in this river. Using the field data and digital image data, the obtained results show that multivariate regression approaches and high-resolution remote sensing could monitor and predict the...