8,153 research outputs found

    The Lockheed OSO-8 program. Task 2: Analysis of data from the high resolution ultraviolet spectrometer experiment

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    The complete set of C 4 time sequences generated by the University of Colorado high resolution ultraviolet spectrometer experiment on OSO-8 were examined in a comprehensive and systematic fashion. As a result a new limit is placed on the acoustic flux passing through the transition zone of the Sun's atmosphere. It is found to be three orders of magnitude too small to heat the corona, and is consistent with zero. In collaborative efforts, the properties of transient C 4 brightenings were examined in considerable detail

    Dynamic evolution of the source volumes of gradual and impulsive solar flare emissions

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    This study compares flare source volumes inferred from impulsive hard X-rays and microwaves with those derived from density sensitive soft X-ray line ratios in the O VII spectrum. The data for this study were obtained with the SMM Hard X-Ray Burst Spectrometer, Earth-based radio observatories, and the SOLEX-B spectrometer on the P78-1 satellite. Data were available for the flares of 1980 April 8, 1980 May 9, and 1981 February 26. The hard X-ray/microwave source volume is determined under the assumption that the same electron temperature or power law index characterizes both the source of hard X-rays and the source of microwaves. The O VII line ratios yield the density and volume of the 2 X 10 to the 6th K plasma. For all three flares, the O VII source volume is found to be smallest at the beginning of the flare, near the time when the impulsive hard X-ray/microwave volume reaches its first maximum. At this time, the O VII volume is three to four orders of magnitude smaller than that inferred from the hard X-ray/microwave analysis. Subsequently, the O VII source volume increases by one or two orders of magnitude then remains almost constant until the end of the flare when it apparently increases again

    Vegetation forest island edges: A preliminary report

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    As the original native forest has been dissected by roads and replaced by farms or towns, the amount of forest edge relative to the area of forest interior has greatly increased. Today forest edge communities are widespread in many man-modified landscapes. However, the role the edge community plays in the regional landscape, and the extent of and variation in the edge community are relatively undefined. The purpose of this study is to determine the nature of forest edge communities. The specific objectives of the study are to: (1) quantitatively survey and assess the forest edge community; (2) determine how forest edge vegetation differs from that of the forest interior; (3) determine if the directional aspect affects the edge vegetation and (4) present guidelines and suggestions for the management of forest habitat islands, particularly as they relate to the edge community

    Rocket studies of solar corona and transition region

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    The XSST (X-Ray Spectrometer/Spectrograph Telescope) rocket payload launched by a Nike Boosted Black Brant was designed to provide high spectral resolution coronal soft X-ray line information on a spectrographic plate, as well as time resolved photo-electric records of pre-selected lines and spectral regions. This spectral data is obtained from a 1 x 10 arc second solar region defined by the paraboloidal telescope of the XSST. The transition region camera provided full disc images in selected spectral intervals originating in lower temperature zones than the emitting regions accessible to the XSST. A H-alpha camera system allowed referencing the measurements to the chromospheric temperatures and altitudes. Payload flight and recovery information is provided along with X-ray photoelectric and UV flight data, transition camera results and a summary of the anomalies encountered. Instrument mechanical stability and spectrometer pointing direction are also examined

    Automated verification of shape, size and bag properties.

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    In recent years, separation logic has emerged as a contender for formal reasoning of heap-manipulating imperative programs. Recent works have focused on specialised provers that are mostly based on fixed sets of predicates. To improve expressivity, we have proposed a prover that can automatically handle user-defined predicates. These shape predicates allow programmers to describe a wide range of data structures with their associated size properties. In the current work, we shall enhance this prover by providing support for a new type of constraints, namely bag (multi-set) constraints. With this extension, we can capture the reachable nodes (or values) inside a heap predicate as a bag constraint. Consequently, we are able to prove properties about the actual values stored inside a data structure

    Evaluation of M-Sites Using PDAs

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    As mobile sites (m-sites) are introduced a very relevant question to ask is “How should these sites be different from the typical websites developed for desktop PCs?” This paper presents an initial, exploratory attempt to address some issues related to m-sites. This evaluation of sites was conducted using wireless PDAs in a WLAN environment. The results indicated that regular sites and m-sites differed significantly in perceived search engine functionality. The evaluated m-sites showed little differences across various industries. A discussion of these results as well as recommendations for managers and academic researchers are provided

    Assessing Progress In Advertising-Related Scale Development & Usage

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    An awareness in the advertising industry of the inadequacy of current practices in copy testing led to the development of  PACT (Positioning Advertising Copy Testing), a statement of fundamental copy testing principles developed by  twenty-one of the world's leading advertising agencies.  A primary concern of this coalition was that too much reliance had been placed on single-item measures to assess the performance of ads, with a concurrent lack of validation of the measures being used.  Subsequently, few studies have followed up on the PACT recommendations, resulting in little in the way of objective data to assess the progress made in the development and use of multi-item scales.  This study offers an initial examination of the progress made in response to the PACT recommendations by developing an inventory and evaluation of advertising-related scales.  Insights from this analysis lead to specific observations regarding the state of the art in advertising research as well as recommendations for future scale research

    Using parent metaphors for learning about the neonatal care experience: an interpretive perspective

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    © 2019 The Author(s). The final, definitive version of this paper has been published in Journal of Child Health Care by Sage Publications Ltd. All rights reserved. It is available at: https://doi.org/10.1177/1367493519875853.This study focuses on how metaphors are used by parents who have had a premature baby to describe their neonatal care experience and how these can contribute to empathic learning of health professionals. In health, metaphors are commonly used to communicate and explain difficult topics. When patients tell their story, metaphor can be a means of expression from which we can learn about their experience of illness or hospitalisation. Limited research exits on how metaphor can improve our understanding of parent’s emotional experience in neonatal care and subsequently inform education in this field. Employing narrative inquiry within an interpretive, constructivist paradigm, 20 narrative interviews with 23 parents of premature babies were analysed using a process of metaphor identification. Findings revealed common metaphors used to describe experience. Metaphor clusters used by parents in order of frequency were journeying, altered reality, darkness, breaking, connections, fighting, salvation and being on the edge. Parents widely used compelling and emotive metaphors to describe and express both difficult and challenging times as well as progression forward. Metaphors serve as a powerful way for health professionals to learn about the emotional experiences of parents and potentially enhance their empathic understanding.Peer reviewe

    Cuban Fulgorina. 1. The Families Tropiduchidae and Acanaloniidae

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