Parallel multigrid methods are very prominent tools for solving huge systems of (non-)linear equations arising from the discretisation of PDEs, as for instance in Computational Fluid Dynamics (CFD). The superiority of multigrid methods in regard of numerical complexity mainly stands and falls with the smoothing algorithms (‘smoother’) used. Since the inherent highly recursive character of many ...

Conventional cellular wireless networks were designed with the purpose of providing high throughput for the user and high capacity for the service provider, without any provisions of energy efficiency. As a result, these networks have an enormous Carbon footprint. In this note, we describe the sources of the inefficiencies in such networks. First we quantify how much Carbon footprint such netwo...

We use a consumption based asset pricing model to show that the predictability of excess returns on risky assets can arise from only two sources: (1) stochastic volatility fundamental variables, or (2) departures rational expectations give rise predictable investor forecast errors and market inefficiency. While controlling for volatility, we find variable which measures non-fundamental noise in...

The correlated models are introduced in this article regarding revenue efficiency and profit efficiency in dynamic network production systems. The proposed models are not only applicable in measuring efficiency of divisional, periodical and overall efficiencies, but recognizing the exact sources of inefficiency with respect to revenue and profit efficiencies. Two numerical examples, consisting ...

PURPOSES To assess the relationship between hospitals' X-inefficiency levels and overall care quality based on the National Quality Forum's 27 safe practices score and to improve the analytic strategy for assessing X-inefficiency. METHODOLOGY The 2005 versions of the American Hospital Association and Leapfrog Group's annual surveys were the basis of the study. Additional case mix indices and ...