5,729 research outputs found

    Methodology for tidal turbine representation in ocean circulation model

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    The present method proposes the use and adaptation of ocean circulation models as an assessment tool framework for tidal current turbine (TCT) array layout optimization. By adapting both momentum and turbulence transport equations of an existing model, the present TCT representation method is proposed to extend the actuator disc concept to 3-D large-scale ocean circulation models. Through the reproduction of experimental flume tests and grid dependency tests, this method has shown its numerical coherence as well as its ability to simulate accurately both momentum and turbulent turbine-induced perturbations in both near and far wakes in a relatively short period of computation time. Consequently the present TCT representation method is a very promising basis for the development of a TCT array layout optimization tool

    Supernova Constraints and Systematic Uncertainties from the First Three Years of the Supernova Legacy Survey

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    We combine high-redshift Type Ia supernovae from the first three years of the Supernova Legacy Survey (SNLS) with other supernova (SN) samples, primarily at lower redshifts, to form a high-quality joint sample of 472 SNe (123 low-z, 93 SDSS, 242 SNLS, and 14 Hubble Space Telescope). SN data alone require cosmic acceleration at >99.999% confidence, including systematic effects. For the dark energy equation of state parameter (assumed constant out to at least z = 1.4) in a flat universe, we find w = –0.91^(+0.16)_(–0.20)(stat)^(+0.07)_(–0.14)(sys) from SNe only, consistent with a cosmological constant. Our fits include a correction for the recently discovered relationship between host-galaxy mass and SN absolute brightness. We pay particular attention to systematic uncertainties, characterizing them using a systematic covariance matrix that incorporates the redshift dependence of these effects, as well as the shape-luminosity and color-luminosity relationships. Unlike previous work, we include the effects of systematic terms on the empirical light-curve models. The total systematic uncertainty is dominated by calibration terms. We describe how the systematic uncertainties can be reduced with soon to be available improved nearby and intermediate-redshift samples, particularly those calibrated onto USNO/SDSS-like systems

    Marcus Clarke: the Romance of Reality

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    Australia's most durable novel, For the Term of His Natural Life, places Marcus Clarke at the pinnacle of Australia's literary ancestry. His magnum opus has antecedents in his journalism but few scholars have recognised the extent to which Clarke's reportage influenced his fiction. This paper argues he treated journalism and fiction as companions in language, information gathering, theme and truth telling

    Narratives of Diversity in the Corporate Boardroom: What Corporate Insiders Say About Why Diversity Matters

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    Over the last generation, the concept of diversity has become commonplace and taken-for-granted in discourses ranging from law to education to business. In higher education, for example, it is hard to imagine a faculty job search or a student admissions discussion that was not heavily laden with talk of diversity, in the sense of the representative inclusion of women and racial and ethnic minorities in a group or organization. In this paper we present the results of an interview-based study of the discourse of diversity in a particular business setting: the corporate boardroom. Our principal observation is that—thirty-one years after the Supreme Court’s Bakke decision introduced the term into public discourse--corporate insiders appear not to have arrived at a master narrative to explain the pursuit of diversity on boards of directors. Instead, their accounts stress a variety of factors and feature few concrete examples

    Dangerous Categories: Narratives of Corporate Board Diversity

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    In this article, we report the results of a series of interviews with corporate directors about racial, ethnic, and gender diversity on corporate boards. On the one hand, our respondents were clear and nearly uniform in their statements that board diversity was an important goal worth pursuing. Yet when asked to provide examples or anecdotes illustrating why board diversity matters, many subjects acknowledged difficulty in illustrating theory with reference to practice. This expressed reluctance to come to specific terms with general claims about the value of director diversity inspired our title phrase: dangerous categories. That is, while diversity evokes universal acclaim in the abstract, our respondents’ narratives demonstrate that it is an elusive and even dangerous subject to talk about concretely. So we are left with narratives that simultaneously extol difference and express embarrassment with it.This expressed reluctance to come to specific terms with general claims about the value of director diversity inspired our title phrase: dangerous categories. That is, while diversity evokes universal acclaim in the abstract, our respondents’ narratives demonstrate that it is an elusive and even dangerous subject to talk about concretely. So we are left with narratives that simultaneously extol difference and express embarrassment with it

    Africa's Lagging Demographic Transition: Evidence from Exogenous Impacts of Malaria Ecology and Agricultural Technology

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    Much of Africa has not yet gone through a "demographic transition" to reduced mortality and fertility rates. The fact that the continent's countries remain mired in a Malthusian crisis of high mortality, high fertility, and rapid population growth (with an accompanying state of chronic extreme poverty) has been attributed to many factors ranging from the status of women, pro-natalist policies, poverty itself, and social institutions. There remains, however, a large degree of uncertainty among demographers as to the relative importance of these factors on a comparative or historical basis. Moreover, econometric estimation is complicated by endogeneity among fertility and other variables of interest. We attempt to improve estimation (particularly of the effect of the child mortality variable) by deploying exogenous variation in the ecology of malaria transmission and in agricultural productivity through the staggered introduction of Green Revolution, high-yield seed varieties. Results show that child mortality (proxied by infant mortality) is by far the most important factor among those explaining aggregate total fertility rates, followed by farm productivity. Female literacy (or schooling) and aggregate income do not seem to matter as much, comparatively.

    Integrated Numerical Modelling System for Extreme Wave Events at the Wave Hub Site

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    This paper examines an extreme wave event which occurred during a storm at the Wave Hub site in 2012. The extreme wave of 9.57 m height was identified from a time series of the heave data collected by an Oceanor Seawatch Mini II Buoy deployed at the site. An energy density spectrum was derived from this time series and then used to drive a physical model, which represents the extreme wave at 1:20 scale in Plymouth University’s new COAST Lab. The NewWave technique was used to define the input to the physical model. The experiment is reproduced in a numerical wave tank using the fully nonlinear CFD library OpenFOAM® and the wave generation toolbox waves2Foam. Results are evaluated, and issues regarding the predictions of a numerical model that is driven by the NewWave input signal are discussed. This study sets the basis for further research in coupling field data, physical modelling and numerical modelling in a more efficient and balanced way. This will lead to the new approach of composite modelling that will be implemented in future work

    Supervision and Training Needs of Practitioners Working in Batterer Intervention Programs

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    Batterer intervention programs (BIPs) seek to address violence in families by working with perpetrators in developing skills to remain nonviolent. The purpose of this study was to explore the supervision and training needs of practitioners who work in batterer intervention programs (BIPs). This study utilized qualitative data collected from hour-long, audio-recorded interviews with three BIP practitioners (one male and two female). Interviews were conducted in a large, Midwestern metro area over a period of three weeks, were transcribed verbatim, and coded for themes by the researcher. Major findings included: Participants were overall satisfied with quality of supervision, which was in contrast with previous research. Participants felt more supervised (even over supervised) than participants in previous research. Finally, specific training and education in batterer intervention, even the field of domestic violence in general appears to be lacking. Social work implications were also discussed. This study is a beginning effort to more closely examine the supervision and training needs of BIP practitioners. Quality training and supervision supports BIP practitioners in their effort to help reduceviolence and abuse in families in the community

    Supervision and Training Needs of Practitioners Working in Batterer Intervention Programs

    Get PDF
    Batterer intervention programs (BIPs) seek to address violence in families by working with perpetrators in developing skills to remain nonviolent. The purpose of this study was to explore the supervision and training needs of practitioners who work in batterer intervention programs (BIPs). This study utilized qualitative data collected from hourlong, audio-recorded interviews with three BIP practitioners (one male and two female). Interviews were conducted in a large, Midwestern metro area over a period of three weeks, were transcribed verbatim, and coded for themes by the researcher. Major findings included: Participants were overall satisfied with quality of supervision, which was in contrast with previous research. Participants felt more supervised (even oversupervised) than participants in previous research. Finally, specific training and education in batterer intervention, even the field of domestic violence in general appears to be lacking. Social work implications were also discussed. This study is a beginning effort to more closely examine the supervision and training needs of BIP practitioners. Quality training and supervision supports BIP practitioners in their effort to help reduceviolence and abuse in families in the community
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