Browsing by Subject "Poor"

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    A cost benefit analysis of a technology bundle aimed at improving the resilience of urban households in Rocklands, Mitchell's Plain
    (2013-10) Odendaal, Rehana; Morar, Jeeten; Conradie, Beatrice
    This paper documents and evaluates the early progress with a project which aims to increase the resilience of poor urban households with a complete technology package consisting of a permaculture food garden and multiple renewable-energy retrofits. The project is PBO facilitated and incorporates substantial training. Beneficiary households are objectively poor, but not destitute. After six months there were still some glitches with the retrofitting, but the gardens were all thriving and were yielding some produce and substantial pride for their owners. Retrofitting accounts for 39% of project costs, the gardens for 27%, and overheads (including training) for the remaining 34%. We have estimated the unit cost of expansion to be R6 435 for the basic model and R16 381 for an unsubsidised advanced model (in 2013 prices). This initiative has been expensive, perhaps unnecessarily so, but is also successful against great odds, not least of which is the exceptionally difficult growing conditions which characterise the Cape Flats. We identified appropriate support, flexible design and on-going monitoring as important issues going forward, but we nonetheless think that the project is one of the most successful of its kind and that it could be replicated on a larger scale at modest additional cost.
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    Open Access
    H i kinematics, mass distribution and star formation threshold in NGC 6822, using the SKA pathfinder KAT-7
    (2017) Namumba, B; Carignan, C; Passmoor, S; de Blok, W J G
    We present high sensitivity H I observations of NGC 6822, obtained with the Karoo Array Telescope (KAT-7). We study the kinematics, the mass distribution and the star formation thresholds. The KAT-7 short baselines and low system temperature make it sensitive to large-scale, low surface brightness emission. The observations detected ∼ 23 per cent more flux than previous Australian Telescope Compact Array observations. We fit a tilted ring model to the H I velocity field to derive the rotation curve (RC). The KAT-7 observations allow the measurement of the rotation curve of NGC 6822 out to 5.8 kpc, ∼1 kpc further than existing measurements. NGC 6822 is seen to be dark matter dominated at all radii. The observationally motivated pseudo-isothermal dark matter (DM) halo model reproduces well the observed RC while the Navarro Frank-White DM model gives a poor fit to the data. We find the best-fitting mass-to-light ratio (M/L) of 0.12 ± 0.01 which is consistent with the literature. The modified Newtonian dynamics gives a poor fit to our data. We derive the star formation threshold in NGC 6822 using the H I and H α data. The critical gas densities were calculated for gravitational instabilities using the Toomre-Q criterion and the cloud-growth criterion. We found that in regions of star formation, the cloud-growth criterion explains star formation better than the Toomre-Q criterion. This shows that the local shear rate could be a key player in cloud formation for irregular galaxies such as NGC 6822.