We consider time dependent thermal fluid structure interaction. The respective models are the compressible Navier-Stokes equations and the nonlinear heat equation. A partitioned coupling approach via a Dirichlet-Neumann method and a fixed point iteration is employed. As a reference solver a previously developed efficient time adaptive higher order time integration scheme is used. To improve upo...

This paper presents a method for solving Poisson’s equation with Dirichlet boundary conditions on an irregular bounded three-dimensional region. The method uses a nodal-point discretization and adaptive mesh refinement (AMR) on Cartesian grids, and the AMR multigrid solver of Almgren. The discrete Laplacian operator at internal boundaries comes from either linear or quadratic (Shortley–Weller) ...

This paper focuses on suppressing spectral overlap for sub-band spectral estimation, with which we can greatly decrease the computational complexity of existing spectral estimation algorithms, such as nonlinear least squares spectral analysis and non-quadratic regularized sparse representation. Firstly, our study shows that the nominal ability of the high-order analysis filter to suppress spect...

Iterative solution methods for large, sparse linear systems of equations usually require significantly less time and memory than direct methods, and so are important in solving the systems which often arise in computational fluid dynamics. There are a number of eztrapolation algorithms which have been closely studied in the past as methods of accelerating convergence of iterative processes [3]....

The MILC collaboration computation of heavy-light decay constants is described. Results for fB, fBs , fD, fDsand their ratios are presented. These results are still preliminary, but the analysis is close to being completed. Sources of systematic error, both within the quenched approximation and from quenching itself, are estimated, although the latter estimate is rather crude. A sample of our r...

The MILC collaboration computation of heavy-light decay constants is described. Results for f B , f Bs , f D , f Ds and their ratios are presented. These results are still preliminary, but the analysis is close to being completed. Sources of systematic error, both within the quenched approximation and from quenching itself, are estimated, although the latter estimate is rather crude. ?0:01 , wh...

In this paper, a new extrapolation economy cascadic multigrid method is proposed to solve the image restoration model. The combines formula and quadratic interpolation design nonlinear prolongation operator, which provides more accurate initial values for fine grid level. An edge preserving denoising operator constructed remove noise preserve edges. local smoothing reduces influence of staircas...

While radiobiological data are conveniently fitted by a linear quadratic formula to data of limited dynamic range at doses typically exceeding 1 Gy, they are extrapolated linearly to doses below a milligray for the evaluation of low dose RBEs. However a single relativistic electron passing through a cell nucleus deposits a “dose” there in the neighborhood of a milligray. The validity of the lin...

Acoustic radiation force impulse (ARFI) imaging is being utilized to investigate mechanical properties ofcardiac tissue. The underlying physiological motion, however, presents a major challenge. This paper aims to investigate the effectiveness of various physiological motion filters using in vivo canine data with a simulated ARFI push pulse. Ideally, the motion filter will exactly model the phy...