103 research outputs found

    Space station automation of common module power management and distribution, volume 2

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    The new Space Station Module Power Management and Distribution System (SSM/PMAD) testbed automation system is described. The subjects discussed include testbed 120 volt dc star bus configuration and operation, SSM/PMAD automation system architecture, fault recovery and management expert system (FRAMES) rules english representation, the SSM/PMAD user interface, and the SSM/PMAD future direction. Several appendices are presented and include the following: SSM/PMAD interface user manual version 1.0, SSM/PMAD lowest level processor (LLP) reference, SSM/PMAD technical reference version 1.0, SSM/PMAD LLP visual control logic representation's (VCLR's), SSM/PMAD LLP/FRAMES interface control document (ICD) , and SSM/PMAD LLP switchgear interface controller (SIC) ICD

    Space station automation of common module power management and distribution

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    The purpose is to automate a breadboard level Power Management and Distribution (PMAD) system which possesses many functional characteristics of a specified Space Station power system. The automation system was built upon 20 kHz ac source with redundancy of the power buses. There are two power distribution control units which furnish power to six load centers which in turn enable load circuits based upon a system generated schedule. The progress in building this specified autonomous system is described. Automation of Space Station Module PMAD was accomplished by segmenting the complete task in the following four independent tasks: (1) develop a detailed approach for PMAD automation; (2) define the software and hardware elements of automation; (3) develop the automation system for the PMAD breadboard; and (4) select an appropriate host processing environment

    Enhancing the social issues components in our computing curriculum: Computing for the social good

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    The acceptance and integration of social issues into computing curricula is still a work in progress twenty years after it was first incorporated into the ACM Computing Curricula. Through an international survey of computing instructors, this paper corroborates prior work showing that most institutions include the societal impact of ICT in their programs. However, topics often concentrate on computer history, codes of ethics and intellectual property, while neglecting broader issues of societal impact. This paper explores how these neglected topics can be better developed through a subtle change of focus to the significant role that ICT plays in addressing the needs of the community. Drawing on the survey and a set of implementation cases, the paper provides guidance by means of examples and resources to empower teaching teams to engage students in the application of ICT to bring about positive social outcomes – computing for the social good

    Exploring sources of variation in thermoluminescence emissions and anomalous fading in alkali feldspars

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    Alkali feldspar is routinely used in retrospective dosimetry using luminescence methods. However there is a signal loss over time, termed ‘anomalous fading’, which results in age underestimation if uncorrected. Although significant improvements have been made in recent years, luminescence dating of feldspars remains challenging. This paper investigates the relationships between chemistry, structural state and the scale of exsolution with thermoluminescence (TL) emission spectra and infrared stimulated luminescence (IRSL) fading rates. We measure TL emission spectra, where possible linking the recombination site to physical features of the feldspar crystals. We show that fading rates are lowest in ordered end-member Na- and K-feldspars but significantly greater in disordered end-members, showing that Al–Si order influences fading. As well as having very low fading rates, ordered end-member samples have distinctive TL emission spectra, with the yellow-green emission dominant, while all other samples have a dominant blue emission. Perthite, i.e. exsolved members of the (Na,K)-feldspar solid solution, show greater fading than disordered end-members and fading is greatest in semi-coherent macroperthite. We propose that the state of Al–Si-order, and the occurrence of defects and dislocations at the perthite lamellar interfaces influence anomalous fading rates in feldspar

    "It's a can of worms": understanding primary care practitioners' behaviours in relation to HPV using the Theoretical Domains Framework

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    Background: The relationship between infection with high-risk human papillomavirus (HPV) and cervical cancer is transforming cervical cancer prevention. HPV tests and vaccinations have recently become available. In Ireland, as elsewhere, primary care practitioners play a key role in prevention. ATHENS (A Trial of HPV Education and Support) aims to develop a theorybased intervention to support primary care practitioners in their HPV-related practice. This study, the first step in the intervention development process, aimed to: identify HPV-related clinical behaviours that the intervention will target; clarify general practitioners’ (GPs’) and practice nurses’ roles and responsibilities; and determine factors that potentially influence clinical behaviour. A secondary objective was to informally assess the utility of the Theoretical Domains Framework (TDF) in understanding clinical behaviours in an area with an evolving evidence-base. Methods: In-depth semi-structured telephone interviews were conducted with GPs and practice nurses. The topic guide, which contained open questions and HPV-related clinical scenarios, was developed through literature review and clinical experience. Interview transcripts were content-analysed using the TDF as the coding framework. Results: 19 GPs and 14 practice nurses were interviewed. The major HPV-related clinical behaviours were: initiating a discussion about HPV infection with female patients; offering/recommending HPV vaccination to appropriate patients; and answering patients’ questions about HPV testing. While the responsibility for taking smears was considered a female role, both male and female practitioners dealt with HPV-related issues. All 12 theoretical domains arose in relation to HPV infection; the domains judged to be most important were: knowledge, emotion, social influences, beliefs about capabilities and beliefs about consequences. Eleven domains emerged in relation to HPV vaccination, with beliefs about consequences, social influences, knowledge and environmental context and resources judged to be the most important. Nine domains were relevant to HPV testing, with knowledge and beliefs about capabilities judged to be the most important. Conclusions: The findings confirm the need for an intervention to support primary care practitioners around HPV and suggest it should target a range of theoretical domains. The TDF proved valuable in analysing qualitative data collected using a topic guide not specifically designed to capture TDF domains and understanding clinical behaviours in an area with an evolving evidence-base

    Charged-Particle Decay from Giant Monopole Resonance in Si-28

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    Journals published by the American Physical Society can be found at http://publish.aps.org
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