Browsing by Subject "production"

Now showing 1 - 3 of 3
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    Open Access
    Accurate Recovery of H i Velocity Dispersion from Radio Interferometers
    (2017) Ianjamasimanana, R; Blok, W J G de; Heald, George H
    Gas velocity dispersion measures the amount of disordered motion of a rotating disk. Accurate estimates of this parameter are of the utmost importance because the parameter is directly linked to disk stability and star formation. A global measure of the gas velocity dispersion can be inferred from the width of the atomic hydrogen (H I) 21 cm line. We explore how several systematic effects involved in the production of H I cubes affect the estimate of H I velocity dispersion. We do so by comparing the H I velocity dispersion derived from different types of data cubes provided by The H I Nearby Galaxy Survey. We find that residual-scaled cubes best recover the H I velocity dispersion, independent of the weighting scheme used and for a large range of signal-to-noise ratio. For H I observations, where the dirty beam is substantially different from a Gaussian, the velocity dispersion values are overestimated unless the cubes are cleaned close to (e.g., ˜1.5 times) the noise level.
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    Production, inequality and poverty linkages in South Africa
    (2010) Ngepah, Nicholas
    The Kuznets inequality-development hypothesis can be tested with time-series data rather than the cross-section analyses found in earlier literature. Single-country time-series analysis cannot be done without addressing endogeneity between output and inequality. South Africa has been under-researched in this area due to a lack of data. Recent data released by the Presidency of South Africa makes such analysis possible. Besides, the use of a single inequality index in such a multiracial society is likely to capture only average effects. This paper jointly estimates production, inequality (decomposed by sub-group) and poverty with 3sls using South African data. The findings suggest that production is affected negatively by between-group inequality. Credit constraints and interracial tensions are possible causes, generating significant adverse effects that stifle economic productivity. Within-group inequality enhances production, possibly due to within-group social capital. There is evidence of an inverted U-shape relationship between per capita income and between-group inequality, but a U-shaped one between per capita income and within-group inequality. However due to the effects of the active post-apartheid policies — which reduce between-group inequality, but increase within-group inequality — it is doubtful if this relationship is capturing a Kuznets process. There is a significant poverty-increasing (reducing) effect of total and between-group inequalities (output). The abjectly poor seem to suffer more from inequality than others do. Policy efforts have to focus on reducing between-group inequality.
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    Z boson production in p + Pb collisions at √sNN = 5.02 TeV measured with the ATLAS detector
    (2015) Aad, G; Abbott, B; Abdallah, J; Abdinov, O; Aben, R; Abolins, M; AbouZeid, O S; Abramowicz, H; Abreu, H; Abreu, R; Abulaiti, Y; Acharya, B S; Adamczyk, L; Adams, D L; Adelman, J; Adomeit, S; Adye, T; Affolder, A A; Agatonovic-Jovin, T; Agricola, J; Aguilar-Saavedra, J A; Ahlen, S P; Ahmadov, F; Aielli, G; Akerstedt, H; Åkesson, T P A; Akimov, A V; Alberghi, G L; Albert, J; Albrand, S; Alconada Verzini, M J; Aleksa, M
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