1,163 research outputs found

    Jimsphere wind and turbulence exceedance statistic

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    Exceedance statistics of winds and gusts observed over Cape Kennedy with Jimsphere balloon sensors are described. Gust profiles containing positive and negative departures, from smoothed profiles, in the wavelength ranges 100-2500, 100-1900, 100-860, and 100-460 meters were computed from 1578 profiles with four 41 weight digital high pass filters. Extreme values of the square root of gust speed are normally distributed. Monthly and annual exceedance probability distributions of normalized rms gust speeds in three altitude bands (2-7, 6-11, and 9-14 km) are log-normal. The rms gust speeds are largest in the 100-2500 wavelength band between 9 and 14 km in late winter and early spring. A study of monthly and annual exceedance probabilities and the number of occurrences per kilometer of level crossings with positive slope indicates significant variability with season, altitude, and filter configuration. A decile sampling scheme is tested and an optimum approach is suggested for drawing a relatively small random sample that represents the characteristic extreme wind speeds and shears of a large parent population of Jimsphere wind profiles

    A study of jimsphere wind profiles as related to space vehicle design and operations

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    Winds aloft and wind shear analysis from jimsphere wind sensor balloon-radar dat

    A further study of Jimsphere wind profiles as related to space vehicle design and operations

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    Statistical characteristics of wind profiles from Jimsphere balloon sensors for space vehicle desig

    Phi^{zero}-N Bound State

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    We show that the QCD van der Waals attractive potential is strong enough to bind a ϕ0\phi^{0} meson onto a nucleon inside a nucleus to form a bound state. The direct experimental signature for such an exotic state is proposed in the case of subthreshold ϕ0\phi^{0} meson photoproduction from nuclear targets. The production rate is estimated and such an experiment is found to be feasible at the Jefferson Laboratory.Comment: 4 pages, 2 figure

    ARCHERY: a prospective observational study of artificial intelligence-based radiotherapy treatment planning for cervical, head and neck and prostate cancer - study protocol

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    Introduction Fifty per cent of patients with cancer require radiotherapy during their disease course, however, only 10%-40% of patients in low-income and middle-income countries (LMICs) have access to it. A shortfall in specialised workforce has been identified as the most significant barrier to expanding radiotherapy capacity. Artificial intelligence (AI)-based software has been developed to automate both the delineation of anatomical target structures and the definition of the position, size and shape of the radiation beams. Proposed advantages include improved treatment accuracy, as well as a reduction in the time (from weeks to minutes) and human resources needed to deliver radiotherapy. Methods ARCHERY is a non-randomised prospective study to evaluate the quality and economic impact of AI-based automated radiotherapy treatment planning for cervical, head and neck, and prostate cancers, which are endemic in LMICs, and for which radiotherapy is the primary curative treatment modality. The sample size of 990 patients (330 for each cancer type) has been calculated based on an estimated 95% treatment plan acceptability rate. Time and cost savings will be analysed as secondary outcome measures using the time-driven activity-based costing model. The 48-month study will take place in six public sector cancer hospitals in India (n=2), Jordan (n=1), Malaysia (n=1) and South Africa (n=2) to support implementation of the software in LMICs. Ethics and dissemination The study has received ethical approval from University College London (UCL) and each of the six study sites. If the study objectives are met, the AI-based software will be offered as a not-for-profit web service to public sector state hospitals in LMICs to support expansion of high quality radiotherapy capacity, improving access to and affordability of this key modality of cancer cure and control. Public and policy engagement plans will involve patients as key partners

    Personalised service? Changing the role of the government librarian

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    Investigates the feasibility of personalised information service in a government department. A qualitative methodology explored stakeholder opinions on the remit, marketing, resourcing and measurement of the service. A questionnaire and interviews gathered experiences of personalised provision across the government sector. Potential users were similarly surveyed to discuss how the service could meet their needs. Data were analysed using coding techniques to identify emerging theory. Lessons learned from government librarians centred on clarifying requirements, balancing workloads and selective marketing. The user survey showed low usage and awareness of existing specialist services, but high levels of need and interest in services repackaged as a tailored offering. Fieldwork confirmed findings from the literature on the scope for adding value through information management advice, information skills training and substantive research assistance and the need to understand business processes and develop effective partnerships. Concluding recommendations focus on service definition, strategic marketing, resource utilisation and performance measurement

    Measurement of the Electric Form Factor of the Neutron at Q^2=0.5 and 1.0 (GeV/c)^2

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    The electric form factor of the neutron was determined from measurements of the \vec{d}(\vec{e},e' n)p reaction for quasielastic kinematics. Polarized electrons were scattered off a polarized deuterated ammonia target in which the deuteron polarization was perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons in a large solid angle detector. We find G_E^n = 0.0526 +/- 0.0033 (stat) +/- 0.0026 (sys) and 0.0454 +/- 0.0054 +/- 0.0037 at Q^2 = 0.5 and 1.0 (GeV/c)^2, respectively.Comment: 5 pages, 2 figures, as publishe
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