One of the most famous methods to predict the stiffness of short fiber composites is micromechanical modeling. In this study, a Representative Volume Element (RVE) of a beech wood flour natural composite has been designed and the orientation averaging approach has been utilized to predict its stiffness tensor. The novelty of this work is in finding the proper fiber orientation distribution func...

The Local Discontinuous Galerkin (LDG) method is one of several discontinuous Galerkin (DG) methods that has been extensively studied in recent years. In this presentation we discuss several computational issues. After a brief introduction of the method applied to a second order linear operator, we describe the general structure of the discrete linear system and discuss the influence of the met...

A high-order implicit-explicit additive Rung-Kutta time integrator is implemented in a particle-in-cell method based on a high-order discontinuous Galerkin Maxwell solver for simulation of plasmas. The method satisfies Gauss law using a hyperbolic divergence cleaner that transports divergence out of the computational domain at several times the speed of light. The stiffness in the field equatio...

We present an efficient, implicit-explicit numerical method for wave propagation in solids containing fluid-filled cracks, motivated by applications in geophysical imaging of fractured oil/gas reservoirs and aquifers, volcanology, and mechanical engineering. We couple the elastic wave equation in the solid to an approximation of the linearized, compressible Navier–Stokes equations in curved and...

Many studies have examined the effect of different approaches to teaching grammar including explicit and implicit instruction. However, research in this area is limited in a number of respects. One such limitation pertains to the issue of construct validity of the measures, i.e. the knowledge developed through implicit instruction has been measured through instruments which favor th...

Background: Studies on how the shoe insole hardness regulate joint stiffness and transfer energy in the lower extremity during jump landing are scarce. The current study aimed to determine the effectiveness of shoe insole changes in joint power and stiffness during landing from jumps. Methods: Fifteen healthy male athletes volunteered to perform jump-landing in various shoe insole conditions. ...

This paper presents a method for the impedance control of a pneumatic manipulator for peg-in-hole tasks without using a load cell. The control methodology presented contains a sliding mode force controller and an adaptive pressure summation relationship, which enforces the controllable natural stiffness of the pneumatic actuator. This is accomplished by utilizing two three-way proportional spoo...

We propose an efficient numerical algorithm for computing deformations of ‘very’ soft tissues (such as the brain, liver, kidney etc.), with applications to real-time surgical simulation. The algorithm is based on the finite element method using the total Lagrangian formulation, where stresses and strains are measured with respect to the original configuration. This choice allows for pre-computi...

This paper is concerned with time-stepping numerical methods for computing stiff semi-discrete systems of ordinary differential equations for transient hypersonic flows with thermo-chemical nonequilibrium. The stiffness of the equations is mainly caused by the viscous flux terms across the boundary layers and by the source terms modeling finite-rate thermo-chemical processes. Implicit methods a...

The immersed boundary (IB) method is an approach to fluid-structure interaction that uses Lagrangian variables to describe the structure and Eulerian variables to describe the fluid. Explicit time stepping schemes for the IB method require solvers only for Eulerian equations, for which fast Cartesian grid solution methods are available. Such methods are relatively straightforward to develop and...