Version 9 of the Amber simulation programs includes a new semi-empirical hybrid QM/MM functionality. This includes support for implicit solvent (generalized Born) and for periodic explicit solvent simulations using a newly developed QM/MM implementation of the particle mesh Ewald (PME) method. The code provides sufficiently accurate gradients to run constant energy QM/MM MD simulations for many...

Visualisation of taxonomies and sets has recently become an active area of research. Many application fields now require more than a strict classification of elements into a hierarchy tree. Euler diagrams, one of the most natural ways of depicting intersecting sets, may provide a solution to these problems. In this paper, we present an approach for the automatic generation of Euler-like diagram...

In this technical report we study the convergence of Parareal for 2D incompressible flow around a cylinder for different viscosities. Two methods are used as fine integrator: backward Euler and a fractional step method. It is found that Parareal converges better for the implicit Euler, likely because it under-resolves the fine-scale dynamics as a result of numerical diffusion.

We study how a manager’s short-term interest in the firm’s market value may motivate channel stuffing: shipping excess inventory to the downstream channel. Channel stuffing allows a manager to report sales in excess of demand in order to influence investors’ valuation of the firm. We apply an inventory model which highlights the potential role of inventory in the manager’s channel stuffing and ...

Rheological behavior of certain non–Newtonian fluids in engineering sciences is often modeled by power law ansatzes with p ≤ 2. So far, existing numerical analysis for local strong solutions study a fully implicit time discretization and find only restricted ranges of admissible p’s for corresponding error estimates [9]; different nonlinear stabilization strategies which allow a corresponding e...

An alternative term for these diagrams is “Euler-Venn diagrams” but they are often inaccurately called “Venn diagrams”. Venn diagrams often look similar, but must contain all possible intersections of contours. In contrast, Euler diagrams contain any desired combination of intersections between the contours. Visualizations of Venn diagrams are often created by taking advantage of the symmetries...

This note studies the behavior of Euler characteristics and of intersection homology Euler characterstics under proper morphisms of algebraic (or analytic) varieties. The methods also yield, for algebraic (or analytic) varieties, formulae comparing these two kinds of Euler characteristics. The main results are direct consequences of the calculus of constructible functions and Grothendieck group...

A Banach space operator T ∈ B(X ) is polaroid if points λ ∈ isoσσ(T ) are poles of the resolvent of T . Let σa(T ), σw(T ), σaw(T ), σSF+(T ) and σSF−(T ) denote, respectively, the approximate point, the Weyl, the Weyl essential approximate, the upper semi–Fredholm and lower semi–Fredholm spectrum of T . For A, B and C ∈ B(X ), let MC denote the operator matrix (

In this paper we study some of the arithmetic structure that is found in a special kind of semi-ring in the isols. These are the semi-rings [D(Y ),+, ·] that were introduced by J.C.E. Dekker, and that were later shown by E. Ellentuck to model the true universal recursive statements of arithmetic when Y is a regressive isol and is hyper-torre (= hereditarily odd-even = HOE). When Y is regressive...