6,096 research outputs found

    Feyerabend’s Philosophy of Science and its Implications for National Development in Africa

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    The thesis of this article is that Feyerabend’s philosophy of science, hinged on his pillar of ‘anarchism’ and ‘anything goes’ can serve as a challenge for scientific and technological development in Africa. Africa has been largely tagged as ‘underdeveloped’ because she has failed to chart her own course of scientific development, and has somewhat felt satisfied playing the dependent role. This work agrees with Feyerabend’s thesis that knowledge (scientific) is a local commodity designed to solve local problems. Using the textual and contextual methods we contend that every culture, certainly including Africa, can harness her own indigenous scientific categories and develop from her own local perspective. We reason with Feyerabend that Western science is not sacrosanct, nor its method of rationality the only path toward development. The work reveals that Feyerabend’s views, though challenging and somewhat intriguing, are very congenial to our African experience. Thus we conclude by adumbrating some positive implications that his views have for the Africans, especially towards scientific and even technological development

    Numerical simulations of bent, disrupted radio jets

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    We present preliminary results from three-dimensional hydrodynamical simulations designed to investigate the physics of jet bending and disruption. The specific scenario considered here involves a mildly supersonic jet crossing a contact discontinuity at the interface between the interstellar medium (ISM) and the intercluster medium (ICM) and then encountering a cross-wind in the ICM. The resultant morphologies show many of the features observed in radio sources including jet flaring, bending, and extended tails

    Australian teachers and the learning environment: an analysis of teacher response to TALIS 2013

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    Abstract: The OECD Teaching and Learning International Survey (TALIS) is the first international survey programme to focus on the learning environment and the working conditions of teachers in schools. The overarching aim of TALIS is to provide robust, policy relevant indicators and analysis on teachers and the learning environment for an international audience. It aims to provide an opportunity to examine best practice in education systems around the world, to allow countries to identify other education systems facing similar challenges to their own and to learn from other policy approaches. TALIS provides internationally comparable information in the areas of teacher demographic characteristics, school leadership, teacher professional development, systems of feedback and appraisals for the teaching workforce, school effectiveness, and teacher practices and beliefs. As was the case for the 2008 cycle of TALIS, the Department of Education (formerly DEEWR) again commissioned the Australian Council for Educational Research (ACER) to oversee and conduct the implementation of TALIS 2013 in Australia. In Australia, over 2000 teachers and 149 principals in 149 schools comprised the ISCED 2 sample. In the Australian context, ISCED 2 teachers are defined as teachers of students in lower secondary education or, more specifically, teachers of students in Years 7, 8, 9 or 10

    A numerical simulation of galaxy subcluster mergers

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    We present preliminary results of a 3-D numerical simulation of two merging subclusters of galaxies. By self-consistently modelling the intracluster gas and dark matter dynamics, we hope to gain insight as to how the dynamics of both relate to such observables as the cluster x-ray emission, radio source morphology, and velocity dispersions

    How good a map ? Putting small area estimation to the test

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    The authors examine the performance of small area welfare estimation. The method combines census and survey data to produce spatially disaggregated poverty and inequality estimates. To test the method, they compare predicted welfare indicators for a set of target populations with their true values. They construct target populations using actual data from a census of households in a set of rural Mexican communities. They examine estimates along three criteria: accuracy of confidence intervals, bias, and correlation with true values. The authors find that while point estimates are very stable, the precision of the estimates varies with alternative simulation methods. While the original approach of numerical gradient estimation yields standard errors that seem appropriate, some computationally less-intensive simulation procedures yield confidence intervals that are slightly too narrow. The precision of estimates is shown to diminish markedly if unobserved location effects at the village level are not well captured in underlying consumption models. With well specified models there is only slight evidence of bias, but the authors show that bias increases if underlying models fail to capture latent location effects. Correlations between estimated and true welfare at the local level are highest for mean expenditure and poverty measures and lower for inequality measures.Small Area Estimation Poverty Mapping,Rural Poverty Reduction,Science Education,Scientific Research&Science Parks,Population Policies

    Numerical models of jet disruption in cluster cooling flows

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    We present a coherent picture for the formation of the observed diverse radio morphological structures in dominant cluster galaxies based on the jet Mach number. Realistic, supersonic, steady-state cooling flow atmospheres are evolved numerically and then used as the ambient medium through which jets of various properties are propagated. Low Mach number jets effectively stagnate due to the ram pressure of the cooling flow atmosphere while medium Mach number jets become unstable and disrupt in the cooling flow to form amorphous structures. High Mach number jets manage to avoid disruption and are able to propagate through the cooling flow

    Performance of a circular body earth-to-orbit winged transport with various strap-on boosters

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    Various types of twin strap-on boosters were evaluated by applying them to a core vehicle. The core vehicle has a clipped delta wing and a simple circular body, and is equipped with five Space Shuttle main engines. The only propellants in the core vehicle are liquid oxygen and liquid hydrogen. The strap-on boosters investigated include the current Shuttle solid rocket motors with steel cases and advanced solids with graphite composite filament-wound cases. Also, two types of liquid-oxygen/hydrocarbon boosters were investigated - one pair without crossfeed to the core vehicle and one with. The payloads obtained were tabulated for various assumptions, such as power levels on the core vehicle engines, number of engines, and maximum allowable flight dynamic pressures. The payload for the core vehicle with two filament-wound Shuttle solid rocket strap-on boosters was 83,000 lb and the payload for two liquid strap-ons with crossfeed was 84,000 lb. The core vehicle with Shuttle solid rocket strap-on boosters is regarded as a near term technology system
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