Wetting films on chemically heterogeneous substrates

Based on a microscopic density functional theory we investigate the morphology of thin liquidlike wetting films adsorbed on substrates endowed with well-defined chemical heterogeneities. As paradigmatic cases we focus on a single chemical step and on a single stripe. In view of applications in microfluidics the accuracy of guiding liquids by chemical microchannels is discussed. Finally we give a general prescription of how to investigate theoretically the wetting properties of substrates with arbitrary chemical structures.Comment: 56 pages, RevTeX, 20 Figure

Cosmic ray oriented performance studies for the JEM-EUSO first level trigger

JEM-EUSO is a space mission designed to investigate Ultra-High Energy Cosmic Rays and Neutrinos (E > 5 ⋅ 1019 eV) from the International Space Station (ISS). Looking down from above its wide angle telescope is able to observe their air showers and collect such data from a very wide area. Highly specific trigger algorithms are needed to drastically reduce the data load in the presence of both atmospheric and human activity related background light, yet retain the rare cosmic ray events recorded in the telescope. We report the performance in offline testing of the first level trigger algorithm on data from JEM-EUSO prototypes and laboratory measurements observing different light sources: data taken during a high altitude balloon flight over Canada, laser pulses observed from the ground traversing the real atmosphere, and model landscapes reproducing realistic aspect ratios and light conditions as would be seen from the ISS itself. The first level trigger logic successfully kept the trigger rate within the permissible bounds when challenged with artificially produced as well as naturally encountered night sky background fluctuations and while retaining events with general air-shower characteristics

EFFECTS OF RAIL STATIONS AT AIRPORTS IN EUROPE

The effects of rail stations, including high-speed rail, at airports in Europe are discussed in terms of a cost-benefit framework. Rail stations are operational at many European airports and are at the center of interest when road access relief at airports is considered, as well as when rail and air transport complementarity is considered. As public budget deficits are under more scrutiny than in the past and privatization of state-owned public transport companies is being considered, it is of interest to know the extent to which rail stations at airports improve the performance of the rail companies and have a positive impact on the economy as a whole (are of value to taxpayers). The study is based on a cost-benefit analysis of rail stations at five major airports (Brussels, Zurich, Frankfurt, Paris-Orly, and Paris-Charles de Gaulle) and two medium-sized airports (Geneva and Stuttgart). The results of case studies of several rail stations (those in Belgium, France, Germany, and Switzerland), which had wide spectra of technology and operating system backgrounds, showed that the overall effects of rail stations, by taking into account investment costs and the partial effects on the railways, were positive for the major (hub) airports analyzed [except in particular cases for particular reasons (Brussels and Paris-Orly)] but were balanced or negative for the medium-sized airports analyzed. The results show not only the impact of airport size but also that of distance to the airport by rail, because the benefit to users in terms of time and fare savings played a significant role and highlighted the benefits of having access to a rail network as much as possible. Finally, the effects on public transport as a whole (i.e., the effects on all public transport companies at the airport, including taxi and parking operators) were negative