2,182 research outputs found

    Small Engine Component Technology (SECT)

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    A study of small gas turbine engines was conducted to identify high payoff technologies for year-2000 engines and to define companion technology plans. The study addressed engines in the 186 to 746 KW (250 to 1000 shp) or equivalent thrust range for rotorcraft, commuter (turboprop), cruise missile (turbojet), and APU applications. The results show that aggressive advancement of high payoff technologies can produce significant benefits, including reduced SFC, weight, and cost for year-2000 engines. Mission studies for these engines show potential fuel burn reductions of 22 to 71 percent. These engine benefits translate into reductions in rotorcraft and commuter aircraft direct operating costs (DOC) of 7 to 11 percent, and in APU-related DOCs of 37 to 47 percent. The study further shows that cruise missile range can be increased by as much as 200 percent (320 percent with slurry fuels) for a year-2000 missile-turbojet system compared to a current rocket-powered system. The high payoff technologies were identified and the benefits quantified. Based on this, technology plans were defined for each of the four engine applications as recommended guidelines for further NASA research and technology efforts to establish technological readiness for the year 2000

    Young Muslim women's experiences of Islam and physical education in Greece and Britain: a comparative study

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    Previous research suggests that Muslim women can experience particular problems when taking physical education (PE) lessons, for example with dress codes, mixed-teaching and exercise during Ramadan; and they can face restrictions in extra-curricular activities for cultural and religious reasons. The area is under-researched and there is little evidence of comparative studies that explore similarities and differences in cross-national experiences, which is the aim of this paper. Two studies conducted in Greece and Britain that explored the views of Muslim women on school experiences of physical education are compared. Both studies focused on diaspora communities, Greek Turkish girls and British Asian women, living in predominantly non-Muslim countries. Growing concerns about global divisions between 'Muslims and the West' make this a particularly pertinent study. Qualitative data were collected by interviews with 24 Greek Muslim women, and 20 British Muslim women. \ud <P> \ud Physical education has national curriculum status and a similar rationale in both countries but with different cultures of formality and tradition, which impacted on pupils' experiences. Data suggested that Greek and British groups held positive views towards physical education but were restricted on their participation in extra-curricular activities. For the British women religious identity and consciousness of Islamic requirements were more evident than for the Greek women. Differences in stages of acculturation, historical and socio-cultural contexts contributed to less problematic encounters with physical education for Greek Muslims who appeared more closely assimilated into the dominant culture

    “I Don’t Mind Being Ugly but I Don’t Wanna Have Skin Cancer”: A Qualitative Study of Attitudes to UV Exposure and a Facial Morphing Intervention in Men 35 Years and Older

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    Objectives: Skin cancer is a growing problem globally. Older men have been largely ignored in previous research, even though men may generally be prone to riskier exposure to the sun than women. Past research suggests that appearance-focused techniques such as facial morphing can increase motivations to use sun protection among women of all ages, and younger men. Design: was qualitative, consisting of individual interviews. Method: was semi-structured interviews with 25 older men, to examine attitudes to UV exposure and reactions to a facial morphing intervention. Interviews were subjected to thematic analysis. Results: Three themes were constructed: masculine UV exposure; appearance that’s accepted; personal responsibility. The men did not identify gaps in their sun protection behaviour, and demonstrated a lack of concern about ageing and appearance. These attitudes translated into a lack of motivation for behaviour change due to ageing acceptance. However, motivation to change behaviour came from health concerns resulting from the intervention. Conclusions: The men experienced different motivations and barriers for sun protection use than women of similar ages. Facial morphing can be effective with older men, but may need to be reframed to focus on health implications and personal choice

    Geochemical characterization of supraglacial debris via in situ and optical remote sensing methods: a case study in Khumbu Himalaya, Nepal

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    Surface glacier debris samples and field spectra were collected from the ablation zones of Nepal Himalaya Ngozumpa and Khumbu glaciers in November and December 2009. Geochemical and mineral compositions of supraglacial debris were determined by X-ray diffraction and X-ray fluorescence spectroscopy. This composition data was used as ground truth in evaluating field spectra and satellite supraglacial debris composition and mapping methods. Satellite remote sensing methods for characterizing glacial surface debris include visible to thermal infrared hyper- and multispectral reflectance and emission signature identification, semi-quantitative mineral abundance indicies and spectral image composites. Satellite derived supraglacial debris mineral maps displayed the predominance of layered silicates, hydroxyl-bearing and calcite minerals on Khumbu Himalayan glaciers. Supraglacial mineral maps compared with satellite thermal data revealed correlations between glacier surface composition and glacier surface temperature. Glacier velocity displacement fields and shortwave, thermal infrared false color composites indicated the magnitude of mass flux at glacier confluences. The supraglacial debris mapping methods presented in this study can be used on a broader scale to improve, supplement and potentially reduce errors associated with glacier debris radiative property, composition, areal extent and mass flux quantifications

    The merging/AGN connection: A case for 3D spectroscopy

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    We discuss an ongoing study of the connection between galaxy merging/interaction and AGN activity, based on integral field spectroscopy. We focus on the search for AGN ionization in the central regions of mergers, previously not classified as AGNs. We present here the science case, the current status of the project, and plans for future observations.Comment: 4 pages, 3 figure, Euro3D Science Workshop, Cambridge, May 2003, AN, accepte

    GenDT: Mobile Network Drive Testing Made Efficient with Generative Modeling

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    The geomorphological setting of some of Scotland's east coast freshwater mills: a comment on Downward and Skinner (2005) ‘Working rivers: the geomorphological legacy...’

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    Many of the water mills on Scotland's east coast streams, unlike those discussed recently by Downward and Skinner (2005 Area 37 138–47), are found in predominantly bedrock reaches immediately downstream of knickpoints (i.e. bedrock steps). Bedrock knickpoints in the lower reaches of Scottish rivers are a widespread fluvial response to the glacio-isostatic rebound of northern Britain. These steps in the river profile propagate headward over time, but for intervals of a few centuries or so they are sufficiently stable to be exploited for the elevational fall necessary to power the mill wheel. Many of these mills were apparently powered by ‘run-of-the-river’, as are some today that formerly had mill dams. The typical lack of sediment storage along the erosional lower reaches of many Scottish rivers means that failure of mill structures in Scotland will probably have less dramatic geomorphological and management implications than those suggested by Downward and Skinner for southern English rivers

    A nonlinear quantum model of the Friedmann universe

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    A discussion is given of the quantisation of a physical system with finite degrees of freedom subject to a Hamiltonian constraint by treating time as a constrained classical variable interacting with an unconstrained quantum state. This leads to a quantisation scheme that yields a Schrodinger-type equation which is in general nonlinear in evolution. Nevertheless it is compatible with a probabilistic interpretation of quantum mechanics and in particular the construction of a Hilbert space with a Euclidean norm is possible. The new scheme is applied to the quantisation of a Friedmann Universe with a massive scalar field whose dynamical behaviour is investigated numerically.Comment: 11 pages of text + 4 pages for 8 figure
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