39 research outputs found

    Modification of a variational objective analysis model for new equations for pressure gradient and vertical velocity in the lower troposphere and for spatial resolution and accuracy of satellite data

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    Since late 1982 NASA has supported research to develop a numerical variational model for the diagnostic assimilation of conventional and space-based meteorological data. In order to analyze the model components, four variational models are defined dividing the problem naturally according to increasing complexity. The first of these variational models (MODEL I), the subject of this report, contains the two nonlinear horizontal momentum equations, the integrated continuity equation, and the hydrostatic equation. This report summarizes the results of research (1) to improve the way the large nonmeteorological parts of the pressure gradient force are partitioned between the two terms of the pressure gradient force terms of the horizontal momentum equations, (2) to generalize the integrated continuity equation to account for variable pressure thickness over elevated terrain, and (3) to introduce horizontal variation in the precision modulus weights for the observations

    Application of satellite data in variational analysis for global cyclonic systems

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    The goal of the research is a variational data assimilation method that incorporates as dynamical constraints, the primitive equations for a moist, convectively unstable atmosphere and the radiative transfer equation. Variables to be adjusted include the three-dimensional vector wind, height, temperature, and moisture from rawinsonde data, and cloud-wind vectors, moisture, and radiance from satellite data. In order to facilitate thorough analysis of each of the model components, four variational models that divide the problem naturally according to increasing complexity were defined. The research performed during the second year fall into four areas: sensitivity studies involving Model 1; evaluation of Model 2; reformation of Model 1 for greater compatibility with Model 2; development of Model 3 (radiative transfer equation); and making the model more responsive to the observations

    Variational objective analyses for cyclone studies

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    The basic analysis equations, i.e., the two horizontal momentum equations, the hydrostatic equation, and the integrated continuity equation were derived for the nonlinear vertical coordinate, nondimensionalized, and expressed in finite differences on a staggered grid. Special care was taken to transform the hydrostatic equation and the pressure gradient terms of the horizontal momentum equations to nearly eliminate truncation error over steeply sloping terrain. This formulation also eliminated explicit reference to orographically induced variations in the thermodynamic variables so that the variational adjustments are on the scale of the meteorological perturbations. The analysis equations were subjected to the Euler-Lagrange operations as expressed for finite differences and an additional set of five partial differential equations was derived, bringing to nine the number of equations in Model I. Higher order terms, terms containing observed quantities, and terms containing none of the variables to be adjusted were grouped into forcing functions and the equations were solved for the zero order terms. Zero order variables were eliminated between these equations and there resulted two diagnostic equations which take the form of general linear second order partial differential equations with nonconstant coefficients

    The 1980-1981 drought in Illinois causes, dimensions, and impact

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    Hydrologic, meteorological, and climatological aspects of the 1980-1981 drought in Illinois are addressed. The drought is evaluated in terms of precipitation, streamflow, lakes and reservoirs, and groundwater resources of the state. The meteorological conditions that produced the drought also are addressed. Impacts and problems resulting from the drought are discussed along with various actions taken to ameliorate the problems. Although the primary goal of the study was to quantify the drought, primarily in a physical sense, an important secondary goal was to assess the impacts and the actions employed, to derive information needed in future planning and handling of Illinois droughts. The report thus ends with a set of recommendations for coping with future droughts. The 1980-1981 drought was not one of the extreme droughts of record; however, it is important in that it was the most severe drought since those of the early 1950’s. As such, it reflects some new types of impacts on the state’s water resources due to technological, hydrological, and institutional changes since the 1950’s.publishedpeer reviewedOpe

    Managerial Work in a Practice-Embodying Institution - The role of calling, the virtue of constancy

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    What can be learned from a small scale study of managerial work in a highly marginal and under-researched working community? This paper uses the ‘goods-virtues-practices-institutions’ framework to examine the managerial work of owner-directors of traditional circuses. Inspired by MacIntyre’s arguments for the necessity of a narrative understanding of the virtues, interviews explored how British and Irish circus directors accounted for their working lives. A purposive sample was used to select subjects who had owned and managed traditional touring circuses for at least 15 years, a period in which the economic and reputational fortunes of traditional circuses have suffered badly. This sample enabled the research to examine the self-understanding of people who had, at least on the face of it, exhibited the virtue of constancy. The research contributes to our understanding of the role of the virtues in organizations by presenting evidence of an intimate relationship between the virtue of constancy and a ‘calling’ work orientation. This enhances our understanding of the virtues that are required if management is exercised as a domain-related practice

    How to speak of God? Toward a postsecular apologetics

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    This is an Accepted Manuscript of an article published by Taylor & Francis in Practical Theology on 11/04/2018, available online: https://www.tandfonline.com/doi/full/10.1080/1756073X.2018.1460522Against most expectations religion has not vanished from Western culture. If anything, it exercises a greater fascination than ever before. Broadly, we might think of ourselves as occupying a new, 'postsecular' space between a renewed visibility of religion in public life, and a corresponding acknowledgement of the importance of religious values and actors; and persistent and widespread disillusion and scepticism towards religion, and objections to religion as a source of legitimate public discourse. In a world that is more sensitive than ever to religious belief and practice, yet often struggles to accommodate it into secular discourse, how do religious institutions justify their position in a contested and volatile public square? This article argues that the contemporary postsecular context requires a recovery of the ancient practices of Christian apologetics as a form of public, theological witness to the practical value of faith, articulated in both deed and word

    The product of a Petrine circle? A reassessment of the origin and character of 1 Peter

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    © 2002 SAGE PublicationsRecent studies of 1 Peter, especially by John Elliott, have sought to rescue the letter from its assimilation to the Pauline tradition and to establish the view, now widely held, that 1 Peter is the distinctive product of a Petrine circle. After examining the traditions in 1 Peter, both Pauline and non-Pauline, and the names in the letter (Silvanus, Mark and Peter), this essay argues that there is no substantial evidence, either inside or outside the letter, to support the view of 1 Peter as originating from a specifically Petrine group. It is much more plausibly seen as reflecting the consolidation of early Christian traditions in Roman Christianity. Despite the scholarly majority currently in its favour, the view of 1 Peter as the distinctive product of a Petrine tradition from a Petrine circle should therefore be rejected
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