Wobbling of a liquid column between unequal discs

One of the most puzzling results of an experiment on the stability of long liquid columns under microgravity, performed aboard Spacelab-D2 in 1993 and named STACO, aiming at the analysis of deformations of nearly cylindrical liquid columns under several mechanical disturbances, is revisited here. It corresponds to the unexplained breakage of an 85 mm long liquid bridge of low viscosity silicone oil, established between unequal discs of 30 and 28 mm, intended to counterbalance the expected deformation by residual acceleration found in previous flights, and left idle because the vibrations and oscillations to be applied afterwards were not started, for fear of premature breakage. A detailed image analysis is performed to extract the maximum amount of data, to be able to check against available theories for axisymmetric and non-axisymmetric deformations of a liquid column

Predicted Planck Extragalactic Point Source Catalogue

An estimation of the number and amplitude (in flux) of the extragalactic point sources that will be observed by the Planck Mission is presented in this paper. The study is based on the Mexican Hat wavelet formalism introduced by Cayon et al. 2000. Simulations at Planck observing frequencies are analysed, taking into account all the possible cosmological, Galactic and Extragalactic emissions together with noise. With the technique used in this work the Planck Mission will produce a catalogue of extragalactic point sources above fluxes: 1.03 Jy (857 GHz), 0.53 Jy (545 GHz), 0.28 Jy (353 GHz), 0.24 Jy (217 GHz), 0.32 Jy (143 GHz), 0.41 Jy (100 GHz HFI), 0.34 Jy (100 GHz LFI), 0.57 Jy (70 GHz), 0.54 Jy (44 GHz) and 0.54 Jy (30 GHz), which are only slightly model dependent (see text). Amplitudes of these sources are estimated with errors below 15%. Moreover, we also provide a complete catalogue (for the point sources simulation analysed) with errors in the estimation of the amplitude below 10%. In addition we discuss the possibility of identifying different point source populations in the Planck catalogue by estimating their spectral indices.Comment: 13 pages, 2 figures, submitted to MNRA

Implementing online language exams within the Spanish National University Entrance Examination: The PAULEX Universitas Project

[EN] This paper describes the PAULEX Universitas Project, an online system to design, deliver and assess the foreign language exam that is an integral part of the Spanish national university entrance examination. The foreign language exam is compulsory for all students who wish to enrol in higher education. Students can choose to take one of the following language exams: English, French, German, Italian or Portuguese. Every year, approximately 27,000 students take the university exam simultaneously in the Valencian Community (comprised of 3 provinces: Alicante, Castellón and Valencia) and over 25,000 of these take the English language exam. The paper describes the context in which this university entrance exam takes place, with reference to the current changes in Spanish ministerial policies. Illustrations from the platform are included, as well as a discussion on issues relating to the system's management tools, data security and user interaction. The paper concludes by presenting some of the results obtained from a pilot experience conducted in Valencia with more than 200 students and by addressing a number of difficulties encountered concerning the implementation of the PAULEX online examination platform regionally.S687234