Alfred Newton Richards.

Alfred Newton Richards 1876-1966.

Safety Considerations on MRI Systems for Firefighters and Paramedics

Background and Objectives: The use of Magnetic Resonance Imaging (MRI) systems is on the rise and the number of installed systems is constantly increasing all over the world. This raises the possibility for emergency personnel to get in contact with these systems. However, the clothing and working material of paramedics and firefighters is not designed for the use on magnets. M...

Australotarsius—a new genus of the rove beetle tribe Staphylinini from Australia (Coleoptera: Staphylinidae: Staphylininae)

Australotarsius Solodovnikov & Newton, gen. nov., a new genus of rove beetles of the tribe Staphylinini, endemic to Australia, is described and compared to other Staphylinini. It includes two new species, A. grandis Solodovnikov & Newton, sp. n. from Queensland and New South Wales, and A. tasmanicus Solodovnikov & Newton, sp. n. from Tasmania. The systematic position of Australotarsius within S...

Low-rank update of preconditioners for the nonlinear Richards equation

Preconditioners for the Conjugate Gradient method are studied to solve the Newton system with symmetric positive definite (SPD) Jacobian. Following the theoretical work in [1] we start from a given approximation of the inverse of the initial Jacobian, and we construct a sequence of preconditioners by means of a low rank update, for the linearized systems arising in the Picard-Newton solution of...

Newton-Krylov-Multigrid Solvers for Large-Scale, Highly Heterogeneous, Variably Saturated Flow Problems

In this paper, we present a class of solvers developed for the parallel solution of Richards' equation, a model used in variably saturated ow simulations. These solvers take advantage of the fast, robust convergence of globalized Newton methods as well as the parallel scalability of multigrid preconditioners. We compare two multigrid methods. The methods di er primarily in their handling of dis...