Introduction

The report provides a state-of-the-art of methodologies and guidelines related to quality assurance in water resources modelling. The conclusions from the present report will form the basis for the further HarmoniQuA work on establishment of a common glossary and a generic set of guidelines and methodologies. HarmoniQuA aims to be a component of a future infrastructure for model based water management at catchment and river basin scal

Anharmonic Decay of Vibrational States in Amorphous Silicon

Anharmonic decay rates are calculated for a realistic atomic model of amorphous silicon. The results show that the vibrational states decay on picosecond timescales and follow the two-mode density of states, similar to crystalline silicon, but somewhat faster. Surprisingly little change occurs for localized states. These results disagree with a recent experiment.Comment: 10 pages, 4 Postscript figure

A dynamic product flow model for a mixed ecological farm - an ICT application for ecological agriculture

Specialised farming systems, which focus on producing one or few products, are characterised by high productivity but also by high amounts of detrimental emissions and low quality residual products that makes them unsustainable. Mixed ecological farming systems, which focus on several products, are characterised by processes with cyclic product flows and low levels of detrimental emissions that makes them more sustainable. In this article, a model is introduced that provides a tool for developing and managing sustainability at mixed ecological farms. This will be done from a quality assurance perspective. The core of the model is the process informatics layer that connects business control and process control. This approach structures and generates data from business processes and physical processes and in this way acts as a decision-making platform or learning environment. The model can form a basis for an operational or tactical decision-support syste

Development and screening of selective catalysts for the synthesis of clean liquid fuels

This article is a compilation of the research carried out under EEC contract EN3V-0400-D at the Institut für Energieverfahrenstechnik in Jülich and at the Faculty of Chemical Technology and Materials Science, Delft, concerning the development and screening of copper/cobalt-based catalysts for the synthesis of alcohol mixtures from syngas. Analogous work, based on copper/zinc oxide/alumina catalysts, has been performed at the Faculty of Chemical Technology in Twente University at Enschede. This work is described in a companion paper. Comparative tests of several catalysts in a pressure micropulse reactor and in a plug flow tubular reactor, carried out at the Institut für Technische Chemie, TU Braunschweig, are presented in a second companion paper. \ud In the discussion section of the present article the results obtained by the joint groups are compared with the initial objectives of the programme

Quantitative analysis of reo- based service coordination

Quality of Service analysis of composed software systems is an active research area, with the goal of evaluating and improving performance and resource allocation in serviceoriented applications, namely, in the glue code –coordination layer– of such systems. Stochastic Reo offers constructs for service coordination and allows the specification of stochastic values for channels. But its state-of-the-art semantic models fail in several (important) ways. In this paper, we will see how Interactive Markov chains (IMC), proposed as astochastic compositional model of concurrency, can be effectively used to serve as a compositional semantic model for Stochastic Reo. Treating IMC as a direct semantic model, gives rise to more faithful models and has obvious efficiency advantages. Moreover, tool support that exists for IMC is made available, without significant effort, to verify and reason about the coordination layer modelled as Reo connectors.(undefined

Polarized radio emission from extensive air showers measured with LOFAR

We present LOFAR measurements of radio emission from extensive air showers. We find that this emission is strongly polarized, with a median degree of polarization of nearly $99\%$, and that the angle between the polarization direction of the electric field and the Lorentz force acting on the particles, depends on the observer location in the shower plane. This can be understood as a superposition of the radially polarized charge-excess emission mechanism, first proposed by Askaryan and the geomagnetic emission mechanism proposed by Kahn and Lerche. We calculate the relative strengths of both contributions, as quantified by the charge-excess fraction, for $163$ individual air showers. We find that the measured charge-excess fraction is higher for air showers arriving from closer to the zenith. Furthermore, the measured charge-excess fraction also increases with increasing observer distance from the air shower symmetry axis. The measured values range from $(3.3\pm 1.0)\%$ for very inclined air showers at $25\, \mathrm{m}$ to $(20.3\pm 1.3)\%$ for almost vertical showers at $225\, \mathrm{m}$. Both dependencies are in qualitative agreement with theoretical predictions.Comment: 22 pages, 14 figures, accepted for publication in JCA