Heat conduction in an anisotropic inhomogeneous medium is considered. The conductivities vary exponentially in one fixed but arbitrary direction. The Green’s function corresponding to a point source is constructed. Two methods are used, one using Fourier transforms and one involving certain changes of variables in the governing partial differential equation. Solutions in both two and three dime...

let r be a g-graded ring and m be a g-graded r-module. in this article, we introduce the concept of graded weakly classical prime submodules and give some properties of such submodules.

We present the mathematical analysis for the convergence of an h version Finite Element Method (FEM) with piecewise polynomials of degree p ≥ 1, de ned on an exponentially graded mesh. The analysis is presented for a singularly perturbed reaction-di usion and a convection-di usion equation in one dimension. We prove convergence of optimal order and independent of the singular perturbation param...

The free-space Green function for a two-dimensional exponentially graded elastic medium is derived. The shear modulus μ is assumed to be an exponential function of the Cartesian coordinates (x, y), i.e. μ ≡ μ(x, y) = μ0e12, where μ0, β1, and β2 are material constants, and the Poisson ratio is assumed constant. The Green function is shown to consist of a singular part, involving modified Bessel ...

An inhomogeneous layer is sandwiched between homogeneous half-spaces. The layer contains a defect. There are incident waves and the problem is to calculate the scattered waves. Five recent publications are criticised, mainly because of their misuse of the method of images. 2011 Elsevier Ltd. All rights reserved.

Free space Green's functions are derived for graded materials in which the thermal conductivity varies exponentially in one coordinate. Closed form expressions are obtained for the steady state di usion equation, in two and three dimensions. The corresponding boundary integral equation formulations for these problems are derived, and the three-dimensional case is solved numerically using a Gale...

The hardest instances of phase retrieval arise in crystallography, where the signal is periodic and comprised of atomic distributions arranged uniformly in the unit cell of the crystal. We have constructed a graded set of benchmark problems for evaluating algorithms that perform this type of phase retrieval. A simple iterative algorithm was used to establish baseline runtimes that empirically g...

In this work, a singularly perturbed two-point boundary value problem of convection-diiusion type is considered. A hp version nite element method on a strongly graded piecewise uniform mesh of Shishkin type is used to solve the model problem. With the analytic assumption of the input data, it is shown that the method converges exponentially and the convergence is uniformly valid with respect to...