background and aims. there are many edentulous people with severely resorbed residual ridges and non-resilient lining mucosa that are unable to tolerate occlusal forces during functional and parafunctional movements. lining the tissue surface of dentures with a flexible material can theoretically distribute and absorb forces with cushioning effect. the aim of this study was to evaluate the effe...

This paper presents the development of an algorithm based on the discontinuous Galerkin finite element method (DGFEM) for the Euler equations of gas dynamics. The DGFEM is a mixture of a finite volume and finite element method. In the DGFEM the unknowns in each element are locally expanded in a polynomial series and thus the information about the flow state at the element faces can be directly ...

In this paper, a novel approach is proposed to investigate the progressive collapse damage of prismatic thin walled metal columns with different regular cross sections, under the action of axial quasi-static and impact loads. The present work mainly focuses on implementation of some important factors which have been neglected in other studies. These factors include the effect of reducing impact...

background and aims. the purpose of this study was to evaluate initial force and force decay of commercially available elastomeric ligatures and elastomeric separators in active tieback state in a simulated oral environment. materials and methods. a total of 288 elastomeric ligatures and elastomeric separators from three manufacturers (dentaurum, rmo, 3m unitek) were stretched to 100% and 150% ...

background and aims. the aim of this study was to determine the stress patterns within an implant and the effect of different types of connections on load transfer. materials and methods. three different types of implant-abutment connections were selected for this study. sample a: 1.5-mm deep internal hex corresponding to a lead-in bevel; sample b: a tri-channel internal connection; and sample ...

microtubules, the active filaments with tubular shapes, play important roles in a wide range of cellular functions, including structural supports, mitosis, cytokinesis, and vesicular transport, which are essential for the growth and division of eukaryotic cells. finding properties of microtubules is one of the main concerns of scientists. this work helps to obtain mechanical properties of micro...

micro-electro-mechanical systems (mems) are combination of electrical and mechanical components in micron dimensions. in recent years, holding, actuating methods and handling of mems components such asmicrogripper, microsensors and etc. have been deeply studied. microgrippers for handling, positioning andassembling of micro components are very useful so that for clamping need actuation created ...

cold roll-forming is a process in which the roll of sheet is formed by passing continuously through the set of rotary rollers without changing thickness in a cool way until it is formed to the desired profile. in this paper a parametric study on the section twist angle in roll-forming the non-symmetric channel is presented, using finite element simulation. at first finite element simulation res...

In sheet metal forming processes with complex strain paths, a part is subjected to large plastic deformation. This severe plastic deformation leads to high plastic strain localization zones and subsequent accumulation of those strains. Then internal and superficial micro-defects and in other words ductile damage is created. This damage causes quality problems such as fracture. Therefore, design...