Teaching case: Managing an IT carve out at a multi-national enterprise

Research on the information society and the policies and strategies for its creation has tended to discuss them rationally as the national, and occasionally international or regional, responses to changes in the competitive environment. The predominant notion of the information society in various levels of governance has only rarely been critically examined. The paper provides a Foucauldian analysis of the constitution of the information society as a political and policy imperative at the level of the European Union and the multiple effects it had for its member states. Drawing on ideas on governmentality and regimes of truth, I argue that the European Commission continually shaped the rationality and identity of the information society it heralded, by managing to set itself as the legitimate locus of policy for the information society. In revealing the dominant discursive truths about the European information society, the research discusses how the truth claims about the construction of a particular version of the information society and the legitimate loci of its government shaped the degrees of freedom of the Greek policy makers through a range of disciplining and selfdisciplining practices

Millimeter-Wave Aperture Synthesis Imaging of Vega: Evidence for a Ring Arc at 95 AU

We present the first millimeter-wave aperture synthesis map of dust around a main sequence star. A 3'' resolution image of 1.3 mm continuum emission from Vega reveals a clump of emission 12'' from the star at PA 45 deg, consistent with the location of maximum 850 micron emission in a lower resolution JCMT/SCUBA map. The flux density is 4.0+/-0.9 mJy. Adjacent 1.3 mm peaks with flux densities 3.4+/-1.0 mJy and 2.8+/-0.9 mJy are located 14'' and 13'' from the star at PA 67 deg and 18 deg, respectively. An arc-like bridge connects the two strongest peaks. There is an additional 2.4 +/-0.8 mJy peak to the SW 11'' from the star at PA 215 deg and a marginal detection, 1.4+/-0.5 mJy, at the stellar position, consistent with photospheric emission. An extrapolation from the 850 micron flux, assuming F_{1.3mm-0.85mm} proportional to lambda^{-2.8}, agrees well with the total detected flux for Vega at 1.3 mm, and implies a dust emissivity index, beta, of 0.8. We conclude that we have detected all but a very small fraction of the dust imaged by SCUBA in our aperture synthesis map and that these grains are largely confined to segments of a ring of radius 95 AU.Comment: 4 pages, 1 figure, 1 table, accepted for publication in Astrophysical Journal Letter

SENTINEL-1 DATA TO MAP FLOODED AREAS: THE ROLE OF INSAR COHERENCE AND POLARIMETRIC INFORMATION

Τα SAR δεδομένα παρατήρησης της Γης μπορούν να προσφέρουν χάρτες πλημμυρικής έκτασης και πληροφοριών υψηλής ποιότητας για την καλύτερη εκτίμηση του κινδύνου πλημμύρας κατά συνέπεια το σχεδιασμό, καθώς και για την υποστήριξη των πολιτικών αρχών υπέρ της προστασίας κατά τη φάση έκτακτης ανάγκης. Το πεδίο εφαρμογής του παρόντος εγγράφου είναι να δημιουργήσει χάρτες πλημμυρικής έκτασης από μια σειρά εικόνων SAR της λεκάνης του Έβρου, που αντιπροσωπεύει μια διασυνοριακή κοίτη πλημμυρών. Η μελέτη χρησιμοποιεί χρονολογικές σειρές εικόνων SAR του Copernicus δορυφορικού συστήματος Sentinel-1 που καλύπτει την περίοδο Οκτώβριος 2014-Μάιος 2015. Η μεθοδολογία προσπαθεί να προσδιορίσει την πλημμύρα που συμβαίνει σε τρεις κύριες κατηγορίες κάλυψης γης, όπως είναι οι αστικές περιοχές, γυμνά ή κακώς βλάστηση εδάφους και περιοχές με βλάστηση, εκμεταλλευόμενοι τα εναλλασσόμενη πόλωση SAR κανάλια backscattering, και τη συνάφεια συμβολομετρίας για τον καλύτερο χαρακτηρισμό του τοπίου. Χρησιμοποιώντας εναλλασσόμενη πόλωση SAR δεδομένα παρέχει την ευκαιρία να υπάρχει μια καλύτερη κατανόηση και ερμηνεία της ανίχνευσης πλημμύρας λόγω του διαφορετικού τρόπου που αντιδρά η κάλυψη γης σε διαφορετικές 1731 πολώσεις. Έτσι, με την εφαρμογή της εκτίμησης της συμβολομετρικής συνάφειας μπορούμε να επιτύχουμε ένα καλύτερη καταγραφή και γνώση των πλημμυρισμένων περιοχών, στη πάροδο του χρόνου, στη συγκεκριμένη περιοχή.SAR earth observation data can provide high quality flood maps and information to better assess the flood risk accordingly planning as well as to support civil protection authorities during emergency phase. The scope of this paper is to create flood extent maps from a series of SAR scenes of the Evros basin which represents a transboundary floodplain. The study uses time series SAR images of Sentnel-1 ESA’s Copernicus satellite system covering the period October 2014 to May 2015. The methodology tries to identify the flood that occurs in three main land cover classes, such as urban areas, bare or poorly vegetated soil and vegetated areas, taking advantage of co- and cross-polarized SAR backscattering channels, and the InSAR coherence to better characterize the landscape. Dual-pol SAR data provides the opportunity to have a better understanding and interpretation of flood detection due to way different land cover react to different polarizations. Thus, with the implementation of InSAR coherence estimation we may achieve a better record and knowledge of the flooded areas, over time, in the specific region.

Infrared to millimetre photometry of ultra-luminous IR galaxies: new evidence favouring a 3-stage dust model

Infrared to millimetre spectral energy distributions have been obtained for 41 bright ultra-luminous infrared galaxies. The observations were carried out with ISOPHOT between 10 and 200 micron and supplemented for 16 sources with SCUBA at 450 and 850 micron and with SEST at 1.3 mm. In addition, seven sources were observed at 1.2 and 2.2 $\mu$m with the 2.2 m telescope on Calar Alto. These new SEDs represent the most complete set of infrared photometric templates obtained so far on ULIRGs in the local universe.Comment: 23 pages, 11 figures, accepted for publication in Astronomy & Astrophysic

High Mass Star Formation. II. The Mass Function of Submillimeter Clumps in M17

We have mapped an approximately 5.5 by 5.5 pc portion of the M17 massive star-forming region in both 850 and 450 micron dust continuum emission using the Submillimeter Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT). The maps reveal more than 100 dusty clumps with deconvolved linear sizes of 0.05--0.2 pc and masses of 0.8--120 solar masses, most of which are not associated with known mid-infrared point sources. Fitting the clump mass function with a double power law gives a mean power law exponent of alpha_high = -2.4 +/- 0.3 for the high-mass power law, consistent with the exponent of the Salpeter stellar mass function. We show that a lognormal clump mass distribution with a peak at about 4 solar masses produces as good a fit to the clump mass function as does a double power law. This 4 solar mass peak mass is well above the peak masses of both the stellar initial mass function and the mass function of clumps in low-mass star-forming regions. Despite the difference in intrinsic mass scale, the shape of the M17 clump mass function appears to be consistent with the shape of the core mass function in low-mass star-forming regions. Thus, we suggest that the clump mass function in high-mass star-forming regions may be a scaled-up version of that in low-mass regions, instead of its extension to higher masses.Comment: 33 pages, 6 figures, 3 tables. Accepted for publication in the Astrophysical Journa

Observations of T Tauri Disks at Sub-AU Radii: Implications for Magnetospheric Accretion and Planet Formation

We determine inner disk sizes and temperatures for four solar-type (1-2 M$_{\odot}$) classical T Tauri stars (AS 207A, V2508 Oph, AS 205A, and PX Vul) using 2.2 $\mu$m observations from the Keck Interferometer. Nearly contemporaneous near-IR adaptive optics imaging photometry, optical photometry, and high-dispersion optical spectroscopy are used to distinguish contributions from the inner disks and central stars in the interferometric observations. In addition, the spectroscopic and photometric data provide estimates of stellar properties, mass accretion rates, and disk co-rotation radii. We model our interferometric and photometric data in the context of geometrically flat accretion disk models with inner holes, and flared disks with puffed-up inner walls. Models incorporating puffed-up inner disk walls generally provide better fits to the data, similar to previous results for higher-mass Herbig Ae stars. Our measured inner disk sizes are larger than disk truncation radii predicted by magnetospheric accretion models, with larger discrepancies for sources with higher mass accretion rates. We suggest that our measured sizes correspond to dust sublimation radii, and that optically-thin gaseous material may extend further inward to the magnetospheric truncation radii. Finally, our inner disk measurements constrain the location of terrestrial planet formation as well as potential mechanisms for halting giant planet migration.Comment: Accepted for publication in ApJ (May 1, 2005 issue

Line emission from circumstellar disks around A stars

The nature of the tenuous disks around A stars has raised considerable controversy in the literature during the past decade. The debate whether or not the disk around beta Pictoris contains gaseous molecular hydrogen is only the most recent example. Since CO is in general a poor tracer for the gas content of these low mass disks, we discuss here detailed emission line calculations for alternative tracers like C and C+, based on recent optically thin disk models by Kamp & van Zadelhoff (2001). The [CII] 157.7 mum line was searched toward Vega and beta Pictoris -- the most prominent A stars with disks -- using ISO LWS data, and a tentative detection is reported toward the latter object. From a comparison with emission line observations as well as absorption line studies of both stars, the gas-to-dust ratio is constrained to lie between 0.5 and 9 for beta Pictoris. For Vega the [CII] observations indicate an upper limit of 0.2 M_Earth for the disk gas mass. Predicted line intensities of C+ and C are presented for a range of models and appear promising species to trace the gas content in the disks around A stars with future instrumental capabilities (SOFIA, Herschel, APEX and ALMA). Searches for CO emission should focus on the J=3-2 line.Comment: 14 pages, to appear in A&A (accepted

Temperatura superficial de isolantes térmicos e cortinas para a produção animal.

Projeto: 03.07.09.049

Avaliação do tempo de acionamento de aquecedor a diesel na temperatura e umidade do ar.

Projeto/Plano de Ação: 03.07.94.900-04

Optical Spectroscopy of the Surface Population of the rho Ophiuchi Molecular Cloud: The First Wave of Star Formation

We present the results of optical spectroscopy of 139 stars obtained with the Hydra multi-object spectrograph. The objects extend over a 1.3 square degree area surrounding the main cloud of the rho Oph complex. The objects were selected from narrowband images to have H alpha in emission. Using the presence of strong H alpha emission, lithium absorption, location in the Hertzsprung-Russell diagram, or previously reported x-ray emission, we were able to identify 88 objects as young stars associated with the cloud. Strong H alpha emission was confirmed in 39 objects with line widths consistent with their origin in magnetospheric accretion columns. Two of the strongest emission-line objects are young, x-ray emitting brown dwarf candidates with M8 spectral types. Comparisons of the bolometric luminosities and effective temperatures with theoretical models suggest a medianage for this population of 2.1 Myr which is signifcantly older than the ages derived for objects in the cloud core. It appears that these stars formed contemporaneously with low mass stars in the Upper Scorpius subgroup, likely triggered by massive stars in the Upper-Centaurus subgroup.Comment: 35 pages of postscript which includes seven figures (some of which are multi-panel) and four postscript tables. Astronomical Journal (in press