Environmental Quality, the Macroeconomy and Intergenerational Distribution

environment;macroeconomics;distribution;environmental tax;national debt

The repton model of gel electrophoresis

We discuss the repton model of agarose gel electrophoresis of DNA. We review previous results, both analytic and numerical, as well as presenting a new numerical algorithm for the efficient simulation of the model, and suggesting a new approach to the model's analytic solution.Comment: 17 pages including 6 PostScript figures, typeset with LaTeX 2e using the Elsevier macro package elsart.cl

Modelling the aerodynamics of vertical-axis wind turbines in unsteady wind conditions

Most numerical and experimental studies of the performance of vertical-axis wind turbines have been conducted with the rotors in steady, and thus somewhat artificial, wind conditions - with the result that turbine aerodynamics, under varying wind conditions, are still poorly understood. The Vorticity Transport Model has been used to investigate the aerodynamic performance and wake dynamics, both in steady and unsteady wind conditions, of three different vertical-axis wind turbines: one with a straight-bladed configuration, another with a curved-bladed configuration and another with a helically twisted configuration. The turbines with non-twisted blades are shown to be somewhat less efficient than the turbine with helically twisted blades when the rotors are operated at constant rotational speed in unsteady wind conditions. In steady wind conditions, the power coefficients that are produced by both the straight- and the curved-bladed turbines vary considerably within one rotor revolution because of the continuously varying angle of attack on the blades and, thus, the inherent unsteadiness in the blade aerodynamic loading. These variations are much larger, and thus far more significant, than those that are induced by the unsteadiness in the wind conditions

Watering Hope

In the cross of Christ, we find the most profound tension of opposites: life and death. Posting about resurrection hope from In All Things - an online journal for critical reflection on faith, culture, art, and every ordinary-yet-graced square inch of God’s creation. https://inallthings.org/watering-hope