Optimal relaxation parameters are obtained for red-black Gauss-Seidel relaxation in multigrid solvers of a family of elliptic equations. The resulting relaxation schemes are found to retain very high ef-ciency over an appreciable range of coeecients of the elliptic differential operator, yielding simple, inexpensive and fully paralleliz-able smoothers in many situations where less cost-eeective...

We consider the propagation of extremely short pulses through a di-electric thin film containing resonant atoms (two level atoms) with permanent dipole. Assuming that the film width is less than the field wave length, we can solve the wave equation and reduce the problem to a system of generalized Bloch equations describing the resonant atoms. We compute the stationary solutions for a constant ...

Although the electrophysiologic derangement responsible for atrial fibrillation (AF) has been elucidated, how AF remodels the ventricular chamber and affects diastolic function (DF) has not been fully characterized. The previously validated Parametrized Diastolic Filling (PDF) formalism models suction-initiated filling kinematically and generates error-minimized fits to E-wave contours using un...

The purpose of the present paper is to give a brief summary of our recent study on the domain decomposition method from an operator theoretical point of view. There are a large number of works devoted to the mathematical analysis of the domain decomposition methods. Most of these works carry out the convergence analysis without any assumptions of general nature on the geometry of the decomposit...

Shot-peened nickel-base superalloys exhibit 1–2% increase in apparent eddy current conductivity (AECC), which can be exploited for nondestructive residual stress assessment. Experimental evidence indicates that the excess AECC is due in part to elastic strains, i.e., residual stress, and in part to plastic strains, i.e., cold work. The very fact that the conductivity increases rather than decre...

A new relaxation mechanism is shown to arise from overdamped two-level systems above a critical temperature T ∗ ≈ 5 K, thus yielding an explanation for experimental observations in dielectric glasses in the temperature range between T ∗ and the relaxation peak at 50 K. Using the distribution function of the tunnelling model for the parameters of the two-level systems, both the linear decrease o...