The numeric simulation of distributed-parameter systems involving wave propagation typically suffers from dispersion errors. This work considers the wave equation and the Euler-Bernoulli beam equations that appear in the modeling and simulation of railway catenary systems. A versatile phase error criterion is developed based on phase/group velocity errors due to a Finite Difference discretizati...

We have extended previous formulations of the wavepacket molecular dynamics (WPMD) by implementing full antisymmetrization for the electron-electron interaction and by introducing approximate Bloch waves to account for the periodic continuation of the simulation box. The improved antisymmetrization leads to a modified volume element in the Monte-Carlo (MC) sampling which serves to limit an unph...

Sudden cardiac death, caused mostly by ventricular fibrillation, is responsible for at least five million deaths in the world each year. Despite decades of research, the mechanisms responsible for ventricular fibrillation are not well understood. As most computational studies are limited primarily to planar simulations, experiments so far have not elucidated the mechanisms responsible for spati...

The Laser Interferometer Gravitational-wave Observatory (LIGO) has been constructed to directly measure the distortion of spacetime due to an impinging gravitational-wave (GW). LIGO’s biggest challenge is that the size of the signal is tremendously weak, and there are various kinds of noises that need to be suppressed to make the tiny signal visible. In order to assist in tackling this issue, a...

In a two-dimensional version of the modified Hasegawa-Wakatani (HW) model, which describes electrostatic resistive drift wave turbulence, the resistive coupling between vorticity and density does not act on the zonal components (ky = 0). It is therefore necessary to modify the HW model to treat the zonal components properly. The modified equations are solved numerically, and visualization and a...

A parallel algorithm which has sufficient scalability for time accurate solution of a propagating detonation wavefront is developed. The emphasis is placed on reduction of computational time without compromising accuracy. The flow was assumed to be unsteady, inviscid and non-heat-conducting and coupled with finite-rate chemistry. A finite volume formulation was employed to ensure conservation a...

A review of the principles and applications of surface acoustic wave (SAW) devices is given. An implementation of a design method for SAW devices using MATLAB is described. Results of a comparison between the proposed simulation technique and experimental test results are

The ared horn is modeled according to Webster's equation. A change of variables transforms the equation into the form of the one dimensional Schrodinger wave equation. The Schrodinger form facilitates speci cation of arbitrary axisymmetric wavefronts for the acoustic disturbance within the horn. To provide a physically motivated choice of wavefront shape, Poisson's equation is solved inside t...