59 research outputs found

    Study of the Composite Supernova Remnant MSH 11-62

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    We present the analysis of the X-ray data collected during an observation of the supernova remnant (SNR) MSH 11-62 by the Advanced Satellite for Cosmology and Astrophysics (ASCA). We show that MSH 11-62 is a composite remnant whose X-ray emission comes from two distinct contributions. Nonthermal, synchrotron emission, localized to a region of radius (~~)3' (consistent with a point source) dominates the total flux above 2 keV. A second contribution comes from a thermal component, extended up to a radius of (~~)6' and detected only at energies below 2keV. The spatial and spectral analysis imply the presence of a neutron star losing energy at a rate of about (10**36 - 10**37) ergs/s. No pulsed emission is detected and we set a limit on the pulsed fraction of 10%. This is consistent with the lack of a radio pulsar in the remnant, which may indicate that the pulsed emission from the rapidly rotating compact object that should be powering the synchrotron nebula is beamed and our viewing direction is unfavorable. In either event, the central neutron star deposits much of its spin-down energy into the surrounding synchrotron nebula where, through direct imaging with broadband satellites such as ASCA, it is possible to study the energetics and evolution of the compact remnant.Comment: 30 pages, including 5 figures, Latex. To appear in ApJ (May 20, 1998 issue, Vol. 499.

    Plan estratégico de una empresa de partes electrónicas para el mercado automotor 2020-2023

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    En el presente trabajo de investigación, se aplica una serie de herramientas y conceptos adquiridos durante las clases en el Executive MBA en el caso Delta-Signal Corporation de V. G. Narayanan, Lisa Brem, Matthew Packard. La empresa está dedicada al negocio de autopartes para las ensambladoras de automóviles de lujo en la última década; con la presencia de nuevas tecnologías y calidad de productos, ha dado un nuevo giro en el afán de obtener un mayor protagonismo en el mercado

    Six propositions on the sonics of pornography

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    Pornography (and all its contentious pleasures, contested politics and attendant problematics) is enjoying a fresh wave of academic attention. The overwhelming majority of these studies, however, focus on the visual discourses of sexually explicit material. This risks the sonic dimensions of pornography being overlooked entirely. Yet porn is anything but silent. This speculative article maps out some of the ways in which the sounds of pornography (and the pornography of sound) might be approached in the analytical context of gay male culture. Not only do the texts of porn contain assorted sounds (dialogue, soundtracks, non-verbal noises of participation, background and accidental audio), they also seek to prompt sounds (not least the non-verbal noises pornography seeks to elicit during the moments of its consumption) and sometimes depend on sound alone (telephone lines that allow access to recorded narratives or ‘live’ chat). Pornography speaks in particular accents, it mobilizes particular music, it dances to particular tunes and it relies on the pants we hear as much as the pants we see. If queer cultures have their own distinctive worlds of sound, then the sonic armouries of porn play a prominent role within them

    Impulsive noise pollution in the Northeast Atlantic: Reported activity during 2015-2017

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    Underwater noise pollution from impulsive sources (e.g. explosions, seismic airguns, percussive pile driving) can affect marine fauna through mortality, physical injury, auditory damage, physiological stress, acoustic masking, and behavioural responses. Given the potential for large-scale impact on marine ecosystems, some countries are now monitoring impulsive noise activity, coordinated internationally through Regional Seas Conventions. Here, we assess impulsive noise activity in the Northeast Atlantic reported during 2015-2017 to the first international impulsive noise register (INR), established in 2016 under the OSPAR Convention. Seismic airgun surveys were the dominant noise source (67%-83% of annual activity) and declined by 38% during 2015-2017. Reported pile driving activity increased 46%. Explosions and sonar/acoustic deterrent devices both had overall increases in reported activity. Some increases were attributable to more comprehensive reporting in later years. We discuss utilising the INR for risk assessment, target setting, and forward planning, and the implementation of similar systems in other regions

    Comment letters to the National Commission on Commission on Fraudulent Financial Reporting, 1987 (Treadway Commission) Vol. 1

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    https://egrove.olemiss.edu/aicpa_sop/1661/thumbnail.jp
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