3,282 research outputs found

    Materials and construction techniques for cryogenic wind tunnel facilities for instruction/research use

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    The results of the cryogenic wind tunnel program conducted at NASA Langley Research Center are presented to provide a starting point for the design of an instructional/research wind tunnel facility. The advantages of the cryogenic concept are discussed, and operating envelopes for a representative facility are presented to indicate the range and mode of operation. Special attention is given to the design, construction and materials problems peculiar to cryogenic wind tunnels. The control system for operation of a cryogenic tunnel is considered, and a portion of a linearized mathematical model is developed for determining the tunnel dynamic characteristics

    Organizing the innovation process : complementarities in innovation networking

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    This paper contributes to the developing literature on complementarities in organizational design. We test for the existence of complementarities in the use of external networking between stages of the innovation process in a sample of UK and German manufacturing plants. Our evidence suggests some differences between the UK and Germany in terms of the optimal combination of innovation activities in which to implement external networking. Broadly, there is more evidence of complementarities in the case of Germany, with the exception of the product engineering stage. By contrast, the UK exhibits generally strong evidence of substitutability in external networking in different stages, except between the identification of new products and product design and development stages. These findings suggest that previous studies indicating strong complementarity between internal and external knowledge sources have provided only part of the picture of the strategic dilemmas facing firms

    The developmental and initial validation of the Wellbeing Benefits of Everyday Activities Scale (WBEAS) and the Hairstylist Visit Questionnaire (HVQ): A short report

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    BACKGROUND: In general, men seek psychological help less than women do. It could be that men find mental health benefits in other, more everyday, activities e.g. talking with their barber. This study aimed to develop questionnaires to measure the psychological benefits of (a) everyday activities of various kinds, and (b) visiting a hairstylist. METHODS: Cross-sectional online survey. 242 adults completed the questionnaires. Responses were analysed using standard questionnaire development methodology. RESULTS: The two questionnaires showed good psychometric properties in terms of good factor structure, internal reliability and construct validity. Conclusions: The two new questionnaires have been successfully applied to an online sample (see Roper & Barry, 2016). The WBEAS may prove useful in the assessment of various everyday activities such as Men’s Sheds

    A high resolution scintillating fiber tracker with SiPM readout for the PEBS experiment

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    Using thin scintillating fibers with Silicon Photomultiplier (SiPM) readout a mo dular high-resolution charged-particle tracking detector has been designed. The fiber modules consist of 2 x 5 layers of 128 round multiclad scintillating fiber s of 0.250mm diameter. The fibers are read out by four SiPM arrays (8mm x 1mm) e ach on either end of the module.Comment: 6 pages, 5 figures, presented at the ICATPP 1

    Is having a haircut good for your mental health?

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    BACKGROUND: In general, men seek psychological help less than women do, and black men are less likely to seek psychological help than white men. It could be that men find wellbeing benefits in other activities. Barbershops have a reputation amongst the black community as enjoyable places to socialize and bond, therefore the aim of this study was to find out whether black men get wellbeing benefits from going to the barbershop. METHODS: Cross-sectional online survey; 149 white and 53 black participants completed the questionnaires. RESULTS: Analysis revealed that, controlling for age, black men socialised and talked at the hairstylist significantly more than white men or black or white women (p <.01). Conclusions: These are the first empirical findings that black men might find wellbeing benefits from a visit to the barber. Implications for health promotion are discussed

    Foray search: An effective systematic dispersal strategy in fragmented landscapes

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    In the absence of evidence to the contrary, population models generally assume that the dispersal trajectories of animals are random, but systematic dispersal could be more efficient at detecting new habitat and may therefore constitute a more realistic assumption. Here, we investigate, by means of simulations, the properties of a potentially widespread systematic dispersal strategy termed "foray search." Foray search was more efficient in detecting suitable habitat than was random dispersal in most landscapes and was less subject to energetic constraints. However, it also resulted in considerably shorter net dispersed distances and higher mortality per net dispersed distance than did random dispersal, and it would therefore be likely to lead to lower dispersal rates toward the margins of population networks. Consequently, the use of foray search by dispersers could crucially affect the extinction-colonization balance of metapopulations and the evolution of dispersal rates. We conclude that population models need to take the dispersal trajectories of individuals into account in order to make reliable predictions

    HFPK 334: An unusual Supernova Remnant in the Small Magellanic Cloud

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    We present new Australia Telescope Compact Array (ATCA) radio-continuum and XMM-Newton/Chandra X-ray Observatory (CXO) observations of the unusual supernova remnant HFPK 334 in the Small Magellanic Cloud (SMC). The remnant follows a shell type morphology in the radio-continuum and has a size of \sim20~pc at the SMC distance. The X-ray morphology is similar, however, we detect a prominent point source close to the center of the SNR exhibiting a spectrum with a best fit powerlaw with a photon index of Γ=2.7±0.5\Gamma = 2.7 \pm 0.5. This central point source is most likely a background object and cannot be directly associated with the remnant. The high temperature, nonequilibrium conditions in the diffuse region suggest that this gas has been recently shocked and point toward a younger SNR with an age of 1800\lesssim 1800 years. With an average radio spectral index of α=0.59±0.09\alpha=-0.59\pm0.09 we find that an equipartition magnetic field for the remnant is \sim90~μ\muG, a value typical of younger SNRs in low-density environments. Also, we report detection of scattered radio polarisation across the remnant at 20~cm, with a peak fractional polarisation level of 25±\pm5\%.Comment: 19 pages, 6-figures, submitted to A
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