Finite Variation of Fractional Levy Processes

Various characterizations for fractional Levy process to be of finite variation are obtained, one of which is in terms of the characteristic triplet of the driving Levy process, while others are in terms of differentiability properties of the sample paths. A zero-one law and a formula for the expected total variation is also given.Comment: to appear in Journal of Theoretical Probabilit

Production and Properties of the Liquid Scintillators used in the Stereo Reactor Neutrino Experiment

The electron antineutrino spectrum in the Stereo reactor experiment (ILL Grenoble) is measured via the inverse beta decay signals in an organic liquid scintillator. The six target cells of the Stereo detector are filled with about 1800 litres of Gd-loaded liquid scintillator optimised for the requirements of the experiment. These target cells are surrounded by similar cells containing liquid scintillator without the Gd-loading. The development and characteristics of these scintillators are reported. In particular, the transparency, light production and pulse shape discrimination capabilities of the organic liquids are discussed.Comment: 10 pages, 4 figure

Single particles accelerate final stages of capillary break up

Droplet formation of suspensions is present in many industrial and technological processes such as coating and food engineering. Whilst the finite time singularity of the minimum neck diameter in capillary break-up of simple liquids can be described by well known self-similarity solutions, the pinching of non-Brownian suspension depends in a complex way on the particle dynamics in the thinning thread. Here we focus on the very dilute regime where the filament contains only isolated beads to identify the physical mechanisms leading to the pronounced acceleration of the filament thinning observed. This accelerated regime is characterized by an asymmetric shape of the filament with an enhanced curvature that depends on the size and the spatial distribution of the particles within the capillary thread.Comment: accepted for Europhysics Letter

Stability of three neutrino flavor conversion in supernovae

Neutrino-neutrino interactions can lead to collective flavor conversion in the dense parts of a core collapse supernova. Growing instabilities that lead to collective conversions have been studied intensely in the limit of two-neutrino species and occur for inverted mass ordering in the case of a perfectly spherical supernova. We examine two simple models of colliding and intersecting neutrino beams and show, that for three neutrino species instabilities exist also for normal mass ordering even in the case of a fully symmetric system. Whereas the instability for inverted mass ordering is associated with $\Delta m_{31}^2$, the new instability we find for normal mass ordering is associated with $\Delta m_{21}^2$. As a consequence, the growth rate of these new instabilities for normal ordering is smaller by about an order of magnitude compared to the rates of the well studied case of inverted ordering.Comment: 18 pages, 5 figures Minor update on the consistency of the formulae and prefactors, actualized plot

Economic outlook for the Euro area 2003

This article reports the spring forecast of the economic development in the Eurozone, which was carried out within the European Forecasting Network. A modest rise in GDP growth from 1.2% in 2003 up to 2.1% in 2004 is expected. The current weakness in the growth experience is caused by structural factors to a large extent. In particular, labor markets are not flexible enough in most countries.

Determining All Integer Vertices of the PESP Polytope by Flipping Arcs

We investigate polyhedral aspects of the Periodic Event Scheduling Problem (PESP), the mathematical basis for periodic timetabling problems in public transport. Flipping the orientation of arcs, we obtain a new class of valid inequalities, the flip inequalities, comprising both the known cycle and change-cycle inequalities. For a point of the LP relaxation, a violated flip inequality can be found in pseudo-polynomial time, and even in linear time for a spanning tree solution. Our main result is that the integer vertices of the polytope described by the flip inequalities are exactly the vertices of the PESP polytope, i.e., the convex hull of all feasible periodic slacks with corresponding modulo parameters. Moreover, we show that this flip polytope equals the PESP polytope in some special cases. On the computational side, we devise several heuristic approaches concerning the separation of cutting planes from flip inequalities. We finally present better dual bounds for the smallest and largest instance of the benchmarking library PESPlib

»Creative Age« – mehr als ein positives Zukunftsszenario? : Humangeografen untersuchen den Kreativsektor in Frankfurt – neuer Schwerpunkt der städtischen Wirtschaftsförderung

Die Kreativwirtschaft beschäftigt in Frankfurt etwa ebenso viele Menschen wie das Kreditgewerbe, trägt bislang allerdings lediglich 4,6 Prozent zum städtischen Gesamtumsatz bei. Seit einigen Monaten richtet die Frankfurter Wirtschaftsförderung ihr Augenmerk besonders auf den Kreativsektor. Der »1. Frankfurter Kreativwirtschaftsbericht«, den Wirtschaftsdezernent Boris Rhein (CDU) im Sommer der Öffentlichkeit vor stellte, wurde von Humangeografen der Goethe-Universität unter Leitung von Christian Berndt, Pascal Goeke und Peter Lindner erarbeitet