8,924 research outputs found
Climate change vulnerability index for South African aquifers
South Africa is viewed as a water-stressed country with an average annual rainfall of 500 mm and any climatic change could have adverse impacts on water resources of the country. The potential impacts of climate change on water resources and surface hydrology for Africa and Southern Africa have received considerable attention from hydrologists during the past decade. Very little research has been conducted on the future impact of climate change on groundwater resources in South Africa. Climate change can affect groundwater levels, recharge and groundwater contribution to baseflow. To assess these impacts a climate change vulnerability index was developed. This vulnerability-index method is known as the DART index. The parameters considered in the DART method are as follows: depth to water-level change, aquifer type (storativity), recharge and transmissivity. The DART index is used as a regional screening tool to identify areas that could experience possible changes in their groundwater resources as a result of climate change. The current DART index does notaccount for adaptation and migration occurrences
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Editorial.
Welcome to the third issue of our journal . We are delighted to feature in this issue two peer-reviewed papers looking in detail at some of the outcomes of the ring-fenced money used for researcher development in the UK under the guise of Roberts funding. In her paper looking at impact of the training provided by this funding on late stage doctoral student researchers, Walsh and colleagues draw our attention to detailed analysis of impact via a variety of evaluation approaches. She also alerts us to the question of whether such development programmes should run alongside the traditional apprenticeship style training of such students. The second paper by Heading and colleagues provides a detailed example of a development programme event in information management and provides further evidence for impact of such training.
Bai and Hudson move the focus to the research –teaching nexus and highlight the difficulty for TEFL staff in Chinese HEIs to develop a research strand in their careers. The importance in developing research capacity, providing support and mentoring to such staff is shown to be pivotal in their development.
Finally conceptions of research from a variety of viewpoints are analyzed by Pitcher. Pitcher considers how the PhD itself, alongwith how the knowledge and outcomes of PhD research are perceived. In a preliminary survey of students on these matters, Pitcher highlights the importance of alignment with these concepts between student and supervisor thus avoiding difficulties between apprentice and supervisor as the research progresses which might inhibit development
Toward Equations of Galactic Structure
We find that all classes of galaxies, ranging from disks to spheroids and
from dwarf spheroidals to brightest cluster galaxies, lie on a two dimensional
surface within the space defined by the logarithms of the half-light radius,
r_e, mean surface brightness within r_e, I_e, and internal velocity, V^2 =
(1/2)v_c^2 + sigma^2, where v_c is the rotational velocity and sigma is the
velocity dispersion. If these quantities are expressed in terms of kpc,
L_solar/pc^2, and km/s, then log r_e - log V^2 + log I_e + log Upsilon_e + 0.8
= 0, where we provide a fitting function for Upsilon_e, the mass-to-light ratio
within r_e in units of M_solar/L_solar, that depends only on V and I_e. The
scatter about this surface for our heterogeneous sample of 1925 galaxies is
small (< 0.1 dex) and could be as low as ~ 0.05 dex, or 10%. This small scatter
has three possible implications for how gross galactic structure is affected by
internal factors, such as stellar orbital structure, and by external factors,
such as environment. These factors either 1) play no role beyond generating
some of the observed scatter, 2) move galaxies along the surface, or 3) balance
each other to maintain this surface as the locus of galactic structure
equilibria. We cast the behavior of Upsilon_e in terms of the fraction of
baryons converted to stars, eta, and the concentration of those stars within
the dark matter halo, xi = R_{200}/r_e. We derive eta = 1.9 x 10^{-5} (L/L^*)
Upsilon_* V^{-3} and xi = 1.4 V/r_e. Finally, we present and discuss the
distributions of eta and xi for the full range of galaxies. For systems with
internal velocities comparable to that of the Milky Way (149 < V < 163 km/s),
eta = 0.14 +- 0.05, and xi is, on average, ~ 5 times greater for spheroids than
for disks. (Abridged)Comment: submitted to Ap
The Efficient Delivery of Arbitration Services Through Use of the Arbitration Firm
When a company and a union negotiate a collective agreement, they anticipate that disputes will arise during its term
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