statement of problem: impacts and accidents are considered as the main fac- tors in losing the teeth, so the analysis and design of the implants that they can be more resistant against impacts is very important. one of the important nu- merical methods having widespread application in various fields of engineering sciences is the finite element method. among its wide applications, the study of ...

a two-dimensional (2d) single particle model for the copolymerization of propylene-ethylene with heterogeneous ziegler-natta catalyst is developed. the model accounts for the effects of the initial shape of the catalyst and carck/ pore patterns on the copolymer composition, polymerization rate and the average molecular weight properties. the spherical and oblate ellipsoidal shapes of catalyst p...

background: the aim of this work was to study the feasibility of constructing a fast thorax model suitable for simulating lung motion due to respiration using only one ct dataset. materials and methods: for each of six patients with different thorax sizes, two sets of ct images were obtained in single-breath-hold inhale and exhale stages in the supine position. the ct images were then analyzed ...

in recent years, in order to reducing die design and manufacturing costs, multi point forming technique has gained an increasing interest because of its high flexibility. in this process, the conventional fixed shape solid die sets are replaced with a pair of opposite matrices of controllable elements. in this paper, the fundamental principles of multi-point forming was described and the possib...

Modeling of crack propagation by a finite element method under mixed mode conditions is of prime importance in the fracture mechanics. This article describes an application of finite element method to the analysis of mixed mode crack growth in linear elastic fracture mechanics. Crack - growth process is simulated by an incremental crack-extension analysis based on the maximum principal stress c...

In this paper, a modification on the fixed grid finite element method is presented and used in the solution of 2D linear elastic problems. This method uses non-boundary-fitted meshes for the numerical solution of partial differential equations. Special techniques are required to apply boundary conditions on the intersection of domain boundaries and non-boundary-fitted elements. Hence, a new met...

This paper provides an incremental layerwise finite element formulation for the viscoelastic analysis of multilayered pavements.  The constitutive behavior of asphalt concrete is represented by the Prony series. Layerwise finite element has been shown to provide an efficient and accurate tool for the numerical simulation of laminated structures. Most of the previous research on numerical simula...

Analysis of the stresses, displacements, and horizontal strains of the ground subsidence due to underground excavation in rocks can be accomplished by means of a hybridized higher order indirect boundary element/finite difference (BE/FD) formulation. A semi-infinite displacement discontinuity field is discretized (numerically) using the cubic displacement discontinuity elements (i.e. each highe...