1,720 research outputs found

    Methodology for the comparative assessment of the Satellite Power System (SPS) and alternative technologies

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    The energy systems concerned are the satellite power system, several coal technologies, geothermal energy, fission, fusion, terrestrial solar systems, and ocean thermal energy conversion. Guidelines are suggested for the characterization of these systems, side-by-side analysis, alternative futures analysis, and integration and aggregation of data. A description of the methods for assessing the technical, economic, environmental, societal, and institutional issues surrounding the development of the selected energy technologies is presented

    Social media, protest cultures and political subjectivities of the Arab spring

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    This article draws on phenomenological perspectives to present a case against resisting the objectification of cultures of protest and dissent. The generative, self-organizing properties of protest cultures, especially as mobilized through social media, are frequently argued to elude both authoritarian political structures and academic discourse, leading to new political subjectivities or ‘imaginaries’. Stemming from a normative commitment not to over-determine such nascent subjectivities, this view has taken on a heightened resonance in relation to the recent popular uprisings in the Middle East and North Africa. The article argues that this view is based on an invalid assumption that authentic political subjectivities and cultures naturally emerge from an absence of constraint, whether political, journalistic or academic. The valorisation of amorphousness in protest cultures and social media enables affective and political projection, but overlooks politics in its institutional, professional and procedural forms

    Daylighting Prediction Software: Comparative Analysis and Application

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    Daylighting is a beneficial design strategy since it may provide energy savings and contribute to a more sustainable design. In recent studies, daylighting has also been shown to increase staff and student productivity and to decrease absenteeism. The consulting engineer is often faced with the dilemma of how to design a daylighted building. What tools are available to predict the amount of daylighting? What are the design limitations and parameters? How much time is required? How does the data compare to the “real world”? The purpose of this paper is to answer these questions and provide useful information for the design of daylighted areas with the assistance of software-based simulation. A survey was made of the available software programs for the calibrated modeling of light scattered in enclosed spaces. These software packages used algorithms based on either total radiosity (flux transfer) computations or physically accurate ray tracing. A summary of this survey along with the selection criteria used in selecting a software program are presented. “Radiance”, a reverse ray tracing method software package, was chosen for use in the simulations. An existing school was modeled with the Radiance software and predictions of daylighting contributions were compared with actual data taken at the site location. The use of daylighting also requires a highly specialized lighting system. This system incorporates the use of controllable ballasts and lighting sensors to maximize the daylighting contribution to the overall required illumination. Some design criteria for this system is also discussed

    Improving Practice Accessibility Through MyChart Utilization

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    Aims for Improvement Increase patient portal MyChart activation for a cohort of approximately 2,000 patients at JFMA by 1% from February to April 2021. Demonstrate evidence of utilization including appointment scheduling, results review, and communication with providers through MyChart after activation

    Identification and Description of a Silicic Volcaniclastic Layer in Gale Crater, Mars, Using Active Neutron Interrogation

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    The Dynamic Albedo of Neutrons instrument aboard the Mars Science Laboratory rover, Curiosity, has been used to map a stratigraphically conformable layer of high‐SiO² material in Gale crater. Previous work has shown that this material contains tridymite, a high‐temperature/low‐pressure felsic mineral, interpreted to have a volcanic source rock. We describe several characteristics including orientation, extent, hydration, and geochemistry, consistent with a volcaniclastic material conformably deposited within a lacustrine mudstone succession. Relationships with widely dispersed alteration features and orbital detections of hydrated SiO² suggest that this high‐SiO² layer extends at least 17 km laterally. Mineralogical abundances previously reported for this high‐SiO² material indicated that hydrous species were restricted to the amorphous (non‐crystalline) fraction, which is dominated by SiO². The low mean bulk hydration of this high‐SiO² layer (1.85 ± 0.13 wt.% water‐equivalent hydrogen) is consistent with silicic glass in addition to opal‐A and opal‐CT. Persistent volcanic glass and tridymite in addition to opal in an ancient sedimentary unit indicates that the conversion to more ordered forms of crystalline SiO² has not proceeded to completion and that this material has had only limited exposure to water since it originally erupted, despite having been transported in a fluviolacustrine system. Our results, including the conformable nature, large areal extent, and presence of volcanic glass, indicate that this high‐SiO² material is derived from the product of evolved magma on Mars. This is the first identification of a silicic volcaniclastic layer on another planet and has important implications for magma evolution mechanisms on single‐plate planets

    Schools and civil society : corporate or community governance

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    School improvement depends upon mediating the cultural conditions of learning as young people journey between their parochial worlds and the public world of cosmopolitan society. Governing bodies have a crucial role in including or diminishing the representation of different cultural traditions and in enabling or frustrating the expression of voice and deliberation of differences whose resolution is central to the mediation of and responsiveness to learning needs. A recent study of governing bodies in England and Wales argues that the trend to corporatising school governance will diminish the capacity of schools to learn how they can understand cultural traditions and accommodate them in their curricula and teaching strategies. A democratic, stakeholder model remains crucial to the effective practice of governing schools. By deliberating and reconciling social and cultural differences, governance constitutes the practices for mediating particular and cosmopolitan worlds and thus the conditions for engaging young people in their learning, as well as in the preparation for citizenship in civil society

    Observation of electron-antineutrino disappearance at Daya Bay

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    The Daya Bay Reactor Neutrino Experiment has measured a non-zero value for the neutrino mixing angle θ13\theta_{13} with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth_{\rm th} reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GW_{\rm th}-day livetime exposure in 55 days, 10416 (80376) electron antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940¹0.011(stat)¹0.004(syst)R=0.940\pm 0.011({\rm stat}) \pm 0.004({\rm syst}). A rate-only analysis finds sin⁥22θ13=0.092¹0.016(stat)¹0.005(syst)\sin^22\theta_{13}=0.092\pm 0.016({\rm stat})\pm0.005({\rm syst}) in a three-neutrino framework.Comment: 5 figures. Version to appear in Phys. Rev. Let
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