We apply a Runge-Kutta-based waveform relaxation method to initial-value problems for implicit differential equations. In the implementation of such methods, a sequence of nonlinear systems has to be solved iteratively in each step of the integration process. The size of these systems increases linearly with the number of stages of the underlying Runge-Kutta method, resulting in high linear alg...

abstract introduction. temporo-mandibular disorders (tmds) are a group of chronic and common disease that a lot of skeletal, dental and psychologic factors can have an effect on it. proposed treatment to control this disorder consists of wide variety of drugs and non-drugs methods beside dental treatment. some investigations have reffered to relation between tmds and some psychologic factors su...

background: anxiety among patients after surgery can affect their physiological and psychological well-being. the aim of this study was to investigate and compare the effects of benson’s relaxation and rhythmic breathing techniques on postoperative anxiety in candidates for the mastectomy surgery. methods: this randomized controlled clinical trial study was conducted with ninety patients in 201...

There are classes of linear problems for which the matrix-vector product is a time consuming operation because an expensive approximation method is required to compute it to a given accuracy. In recent years different authors have investigated the use of, what is called, relaxation strategies for various Krylov subspace methods. These relaxation strategies aim to minimize the amount of work tha...

SUMMARY Two relaxation schemes for Chebyshev spectral multigrid methods are presented for elliptic equations with Dirichlet boundary conditions. The rst scheme is a pointwise-preconditioned Richardson relaxation scheme and the second is a line relaxation scheme. The line relaxation scheme provides an eecient and relatively simple approach for solving two-dimensional spectral equations. Numerica...

We view the optimal single commodity network flow problem with linear arc costs and its dual as a pair of monotropic programming problems, i.e. problems of minimizing the separable sum of scalar extended real-valued convex functions over a subspace. For such problems directions of cost improvement can be selected from among a finite set of directions--the elementary vectors of the constraint su...

The solution of complex and large scale systems plays a crucial role in recent scientific computations. In particular, large scale stochastic dynamical systems represent very complex systems incorporating the random appearances of physical processes in nature. The development of efficient numerical methods to study such large scale systems, which can be characterized as weakly coupled subsystem...

A population of eight non-overlapping domain decomposition methods for solving elliptic differential equations are viewed and formulated as iterated interface relaxation procedures. A comprehensive review of the underlying mathematical ideas and the computational characteristics is given. The existing theoretical results are also reviewed and high level descriptions of the various algorithms ar...

We study the multicomputer performance of a three-dimensional Navier-Stokes solver based on alternating-direction line-relaxation methods. We compare several multicomputer implementations, each of which combines a particular line-relaxation method and a particular distributed block-tridiagonal solver. In our experiments, the problem size was determined by resolution requirements of the applicat...

background: cardiac syndrome x is a relatively common disorder, and still not much is known about the causative factors or its pathophysiology, which makes it difficult to cure. due to its chronic nature and debilitating symptoms, many patients have significantly reduced quality of life (qol).the purpose of this study was to assess the impact of phase iii cardiac rehabilitation (cr) and relaxat...