Refined position angle measurements for galaxies of the SDSS Stripe 82 co-added dataset

Position angle measurements of Sloan Digital Sky Survey (SDSS) galaxies, as measured by the surface brightness profile fitting code of the SDSS photometric pipeline (Lupton 2001), are known to be strongly biased, especially in the case of almost face-on and highly inclined galaxies. To address this issue we developed a reliable algorithm which determines position angles by means of isophote fitting. In this paper we present our algorithm and a catalogue of position angles for 26397 SDSS galaxies taken from the deep co-added Stripe 82 (equatorial stripe) images.Comment: 4 pages, 4 figures. Data are published on-line at http://www.vo.elte.hu/galmorp

A Congestion Detection Based Traffic Control for Signalized Intersection

The paper investigates a traffic-responsive control method applicable at isolated signalized intersections. The proposed strategy involves three basic parts: a traffic model, a reconfigurable regulator, and a congestion detection filter. Road traffic dynamics is modeled by the well-known store-and-forward approach. The controller is based on the efficient Linear Quadratic Regulator algorithm. The filter is designed by using the modified version (for discrete time case) of the Fundamental Problem of Residual Generation. The main achievement of the system is the ability to deal with a time-varying model parameter, namely the saturation flow rate of the road links. To this end, an error term is estimated continuously by appropriate fault detection algorithm. The predicted error term is further used by the reconfigurable controller which finally aims to mitigate the number of vehicles waiting at the stop line, i.e. the delay caused by the intersection. A simulation study is also carried out to demonstrate the effectiveness of the controller extended by congestion detection filter

The complexity of recognizing minimally tough graphs

A graph is called $t$-tough if the removal of any vertex set $S$ that disconnects the graph leaves at most $|S|/t$ components. The toughness of a graph is the largest $t$ for which the graph is $t$-tough. A graph is minimally $t$-tough if the toughness of the graph is $t$ and the deletion of any edge from the graph decreases the toughness. The complexity class DP is the set of all languages that can be expressed as the intersection of a language in NP and a language in coNP. In this paper, we prove that recognizing minimally $t$-tough graphs is DP-complete for any positive rational number $t$. We introduce a new notion called weighted toughness, which has a key role in our proof

Echinococcus multilocularis: An emerging pathogen in Hungary and Central Eastern Europe?

Echinococcus multilocularis, the causative agent of human alveolar echinococcosis, is reported for the first time in Red Foxes (Vulpes vulpes) in Hungary. This parasite may be spreading eastward because the population of foxes has increased as a consequence of human interventions, and this spread may result in the emergence of alveolar echinococcosis in Central Eastern Europe