1,941 research outputs found

    Flight test evaluation of a separate surface attitude command control system on a Beech 99 airplane

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    A joint NASA/university/industry program was conducted to flight evaluate a potentially low cost separate surface implementation of attitude command in a Beech 99 airplane. Saturation of the separate surfaces was the primary cause of many problems during development. Six experienced professional pilots who made simulated instrument flight evaluations experienced improvements in airplane handling qualities in the presence of turbulence and a reduction in pilot workload. For ride quality, quantitative data show that the attitude command control system results in all cases of airplane motion being removed from the uncomfortable ride region

    Surface Studies of Oxidation of a Single-Grain Quasicrystal

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    We have used Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS) and low-energy electron diffraction (LEED) to characterize the surface properties of a single-grain Al70Pd21Mn9 (APM) quasicrystal (QC) upon oxidation. When oxygen is adsorbed on this surface, a disordered layer is formed at low coverages. This chemisorbed oxygen destroys the five-fold quasiperiodicity completely. Further adsorption of oxygen leads to a thin layer (less than 20 A) of AI oxide which passivates the surface. At elevated temperatures (870 K), adsorption of oxygen induces an enrichment of AI on the surface. This is explained by the exothermicity of its oxide and the possibility of increased mobility of AI at higher temperatures. Al is the only element in this QC which can be oxidized. No evidence of oxidization for Pd and Mn is observed

    Photoelectron spectra of an Al70Pd21Mn9 quasicrystal and the cubic alloy Al60Pd25Mn15

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    Photoelectron spectra of a fivefold quasicrystalline alloy Al70Pd21Mn9 and a related cubic alloy Al60Pd25Mn15 reveal two noteworthy features. The first is that the Pd 3dlines fall at binding energies which are 2.2 eV higher than in pure Pd. A similar shift is observed for Pd in other alloys. The second noteworthy feature is that the Mn 2p3/2 line is very sharp in the quasicrystal. Fitting the experimental peaks with a Doniach-Sunjic line shpae suggests that the position and density of Mn states near EFis very sensitive to the structural and/or chemical environment of Mn in the alloys, and that this accounts for the shape of the 2p3/2 Mn line. The sharpness of the Mn line may be a fingerprint of the quasicrystalline phase within the AlPdMn family

    How to humiliate and shame: A reporter's guide to the power of the mugshot

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    This is an Author's Accepted Manuscript of an article published in Social Semiotics, 24(1), 56-87, 2014, copyright Taylor & Francis, available online at: http://www.tandfonline.com/The judicial photograph – the “mugshot” – is a ubiquitous and instantly recognisable form, appearing in the news media, on the internet, on book covers, law enforcement noticeboards and in many other mediums. This essay attempts to situate the mugshot in a historical and theoretical context to explain the explicit and implicit meaning of the genre as it has developed, focussing in particular on their use in the UK media in late modernity. The analysis is based on the author's reflexive practice as a journalist covering crime in the national news media for 30 years and who has used mugshots to illustrate stories for their explicit and specific content. The author argues that the visual limitations of the standardised “head and shoulders” format of the mugshot make it a robust subject for analysing the changing meaning of images over time. With little variation in the image format, arguments for certain accreted layers of signification are easier to make. Within a few years of the first appearance of the mugshot form in the mid-19th century, it was adopted and adapted as a research tool by scientists and criminologists. While the positivist scientists claimed empirical objectivity we can now see that mugshots played a part in the construction of subjective notions of “the other”, “the lesser” or “sub-human” on the grounds of class, race and religion. These dehumanising ideas later informed the theorists and bureaucrats of National Socialist ideology from the 1920s to 1940s. The author concludes that once again the mugshot has become, in certain parts of the media, a signifier widely used to exclude or deride certain groups. In late modernity, the part of the media that most use mugshots – the tabloid press and increasingly tabloid TV – is part of a neo-liberal process that, in a conscious commercial appeal to the paying audience, seeks to separate rather than unify wider society

    Media justice: Madeleine McCann, intermediatization and "trial by media" in the British press

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    Three-year-old Madeleine McCann disappeared on 3 May 2007 from a holiday apartment in Portugal. Over five years and multiple investigations that failed to solve this abducted child case, Madeleine and her parents were subject to a process of relentless ‘intermediatization’. Across 24–7 news coverage, websites, documentaries, films, YouTube videos, books, magazines, music and artworks, Madeleine was a mediagenic image of innocence and a lucrative story. In contrast to Madeleine’s media sacralization, the representation of her parents, Kate and Gerry McCann, fluctuated between periods of vociferous support and prolonged and libellous ‘trial by media’. This article analyses how the global intermediatization of the ‘Maddie Mystery’ fed into and fuelled the ‘trial by media’ of Kate and Gerry McCann in the UK press. Our theorization of ‘trial by media’ is developed and refined through considering its legal limitations in an era of ‘attack journalism’ and unprecedented official UK inquiries into press misconduct and criminality

    Analysis of Gas-Phase Clusters Made from Laser-Vaporized Icosahedral Al−Pd−Mn

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    An icosahedral Al−Pd−Mn quasicrystal sample is laser vaporized to form metal clusters by gas aggregation. The clusters are subsequently laser ionized and mass analyzed in a time-of-flight mass spectrometer. The mass spectra show cluster compositions which are qualitatively similar to that of the sample. This is consistent with a kinetically controlled cluster growth process. Cluster thermodynamic stability is probed by multiphoton ionization/fragmentation, which induces primarily Al and Mn loss. The resulting spectra are composed of a series of Pd-rich Al−Pd clusters. The average cluster composition is 60 (±1)% Pd. This composition is close to a known eutectic in the Al−Pd system. When manganese is seen on these clusters, it is always in units of Mn3. These results are discussed in terms of relative binding strengths in the Al−Pd−Mn alloy system
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