342 research outputs found
The State of Our Democracy
In the Annual Dullah Omar Memorial Lecture for 2008 Emeritus Archbishop Desmond Tutu reflects on “The State of our Democracy”. The speech commences with a brief historical background of the past that South Africa inherited and sets the tone for the critical assessment that follows. It highlights some of the challenges inherited from the past which, if not dealt with, may “augur ill” for the future. But the overall conclusion is that “[w]e have a wonderful land with immense potential”
SKILLED ARTISANAL AVAILABILITY IN THE GHANAIAN CONSTRUCTION INDUSTRY
The issue of skilled artisanal scarcity is not a current one. It dates as far back as the two world wars. This paper premised on the observation of the unavailability of skillful artisans in the Ghanaian Construction Industry (GCI). The objective of the study was to identify the factors aggravating the skilled artisanal scarcity in Ghana. Using relative important indices as the main statistical analysis tool, the following factors have been identified as the most important factors causing the scarcity situation : Irregular and low remuneration, low motivation, the lack of interest by the youth to take up trades like masonship and carpentry as professions, varying working conditions and technological advancements. The study recommends that an Association of Ghanaian Construction Artisans (AGCA) as a regulatory body to promote the welfare of its members i n other to address the issues raised by this study
Dealing with a traumatic past: the victim hearings of the South African truth and reconciliation commission and their reconciliation discourse
In the final years of the twentieth and the beginning of the twenty-first century, there has been a worldwide tendency to approach conflict resolution from a restorative rather than from a retributive perspective. The South African Truth and Reconciliation Commission (TRC), with its principle of 'amnesty for truth' was a turning point. Based on my discursive research of the TRC victim hearings, I would argue that it was on a discursive level in particular that the Truth Commission has exerted/is still exerting a long-lasting impact on South African society. In this article, three of these features will be highlighted and illustrated: firstly, the TRC provided a discursive forum for thousands of ordinary citizens. Secondly, by means of testimonies from apartheid victims and perpetrators, the TRC composed an officially recognised archive of the apartheid past. Thirdly, the reconciliation discourse created at the TRC victim hearings formed a template for talking about a traumatic past, and it opened up the debate on reconciliation. By discussing these three features and their social impact, it will become clear that the way in which the apartheid past was remembered at the victim hearings seemed to have been determined, not so much by political concerns, but mainly by social needs
The effectiveness and perception of the use of sulphadoxine-pyrimethamine in intermittent preventive treatment of malaria in pregnancy programme in Offinso district of ashanti region, Ghana
Selfsimilar Domain Growth, Localized Structures and Labyrinthine Patterns in Vectorial Kerr Resonators
We study domain growth in a nonlinear optical system useful to explore
different scenarios that might occur in systems which do not relax to
thermodynamic equilibrium. Domains correspond to equivalent states of different
circular polarization of light. We describe three dynamical regimes: a
coarsening regime in which dynamical scaling holds with a growth law dictated
by curvature effects, a regime in which localized structures form, and a regime
in which polarization domain walls are modulationally unstable and the system
freezes in a labyrinthine pattern.Comment: 13 pages, 6 figure
Phase-Locked Spatial Domains and Bloch Domain Walls in Type-II Optical Parametric Oscillators
We study the role of transverse spatial degrees of freedom in the dynamics of
signal-idler phase locked states in type-II Optical Parametric Oscillators.
Phase locking stems from signal-idler polarization coupling which arises if the
cavity birefringence and/or dichroism is not matched to the nonlinear crystal
birefringence. Spontaneous Bloch domain wall formation is theoretically
predicted and numerically studied. Bloch walls connect, by means of a
polarization transformation, homogeneous regions of self-phase locked
solutions. The parameter range for their existence is analytically found. The
polarization properties and the dynamics of walls in one- and two transverse
spatial dimensions is explained. Transition from Bloch to Ising walls is
characterized, the control parameter being the linear coupling strength. Wall
dynamics governs spatiotemporal dynamical states of the system, which include
transient curvature driven domain growth, persistent dynamics dominated by
spiraling defects for Bloch walls, and labyrinthine pattern formation for Ising
walls.Comment: 27 pages, 16 figure
The Energy-Scaling Approach to Phase-Ordering Growth Laws
We present a simple, unified approach to determining the growth law for the
characteristic length scale, , in the phase ordering kinetics of a system
quenched from a disordered phase to within an ordered phase. This approach,
based on a scaling assumption for pair correlations, determines
self-consistently for purely dissipative dynamics by computing the
time-dependence of the energy in two ways. We derive growth laws for conserved
and non-conserved models, including two-dimensional XY models and
systems with textures. We demonstrate that the growth laws for other systems,
such as liquid-crystals and Potts models, are determined by the type of
topological defect in the order parameter field that dominates the energy. We
also obtain generalized Porod laws for systems with topological textures.Comment: LATeX 18 pages (REVTeX macros), one postscript figure appended,
REVISED --- rearranged and clarified, new paragraph on naive dimensional
analysis at end of section I
Dynamic Phase Transition in a Time-Dependent Ginzburg-Landau Model in an Oscillating Field
The Ginzburg-Landau model below its critical temperature in a temporally
oscillating external field is studied both theoretically and numerically. As
the frequency or the amplitude of the external force is changed, a
nonequilibrium phase transition is observed. This transition separates
spatially uniform, symmetry-restoring oscillations from symmetry-breaking
oscillations. Near the transition a perturbation theory is developed, and a
switching phenomenon is found in the symmetry-broken phase. Our results confirm
the equivalence of the present transition to that found in Monte Carlo
simulations of kinetic Ising systems in oscillating fields, demonstrating that
the nonequilibrium phase transition in both cases belongs to the universality
class of the equilibrium Ising model in zero field. This conclusion is in
agreement with symmetry arguments [G. Grinstein, C. Jayaprakash, and Y. He,
Phys. Rev. Lett. 55, 2527 (1985)] and recent numerical results [G. Korniss,
C.J. White, P. A. Rikvold, and M. A. Novotny, Phys. Rev. E (submitted)].
Furthermore, a theoretical result for the structure function of the local
magnetization with thermal noise, based on the Ornstein-Zernike approximation,
agrees well with numerical results in one dimension.Comment: 16 pp. RevTex, 9 embedded ps figure
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