Wavelet-based spatial and temporal multiscaling: Bridging the atomistic and continuum space and time scales
نویسندگان
چکیده
A wavelet-based multiscale methodology is presented that naturally addresses time scaling in addition to spatial scaling. The method combines recently developed atomistic-continuum models and wavelet analysis. An atomistic one-dimensional harmonic crystal is coupled to a one-dimensional continuum. The methodology is illustrated through analysis of the dispersion relation, which is highly dispersive at small spatial scales and, as usual, nondispersive at large ~continuum! scales. It is feasible to obtain the complete dispersion relation through the combination of the atomistic and the continuum analyses. Wavelet analysis in this work is not only used for bridging the atomistic and continuum scales but also for efficiently extracting the dispersion relation from the solution of wave propagation problems.
منابع مشابه
A New Wavelet Based Spatio-temporal Method for Magnification of Subtle Motions in Video
Video magnification is a computational procedure to reveal subtle variations during video frames that are invisible to the naked eye. A new spatio-temporal method which makes use of connectivity based mapping of the wavelet sub-bands is introduced here for exaggerating of small motions during video frames. In this method, firstly the wavelet transformed frames are mapped to connectivity space a...
متن کاملA Space-time Approach to Coupled Atomistic/continuum Simulation
A space-time finite element method employing discontinuous Galerkin approach, for dynamic molecular simulations is proposed. In our approach, a small region of the domain is simulated using fine scale space-time FEM and it is coupled with a coarse scale simulation which employs enriched space-time FEM. The developed approach is motivated by the needs to understand the mechanics and physics that...
متن کاملA Generalized Space-Time Mathematical Homogenization Theory for Bridging Atomistic and Continuum Scales
A generalized space-time mathematical homogenization theory, which constructs an equivalent continuum description directly from molecular dynamics (MD) equations, is developed. The noteworthy theoretical findings of this work are: (i) the coarse scale continuum equations (PDEs) obtained from the homogenization of MD equations are identical to those obtained from the classical homogenization of ...
متن کاملGroundwater Level Forecasting Using Wavelet and Kriging
In this research, a hybrid wavelet-artificial neural network (WANN) and a geostatistical method were proposed for spatiotemporal prediction of the groundwater level (GWL) for one month ahead. For this purpose, monthly observed time series of GWL were collected from September 2005 to April 2014 in 10 piezometers around Mashhad City in the Northeast of Iran. In temporal forecasting, an artificial...
متن کاملA Space-Time Multilevel Method For Molecular Dynamics Simulations
We present a novel multiscale approach for molecular dynamics simulations. It is aimed at bridging discrete scales with either coarse grained discrete or continuum scales. The method consists of the waveform relaxation scheme aimed at capturing the high frequency response of atomistic vibrations and a coarse scale solution in space and time aimed at resolving smooth features (in both space and ...
متن کامل