Joyce Meng Introduction: Ghana’s Economic History in Perspective Although Ghana enjoyed a privileged position in the post-colonial era due to a relatively stable regime with a charismatic leader committed to soliciting international financial support, profitable natural endowments, and a comparatively high stock of human capital, short-term growth belied the atrophy of long-term sustainable dev...

This paper will review the design of statistical studies, and comment on the difficulty of drawing causal inferences from non-experimental data. The most basic design is a comparison of rates for two groups of subjects. Subjects in one group get the treatment of interest; subjects in the other group are the controls. The difficulty is ensuring that the groups are similar, apart from the treatment.

The advent of high resolution infrared resistor arrays, has greatly increased the level of fidelity of infrared sensor testing that can be accomplished in the cost effective laboratory environment. However, the sensor output image quality depends on the uniformity of the projector array. In addition to the advanced proprietary design and fabrication process used to create a highly uniform emitt...

We study time–dependent backgrounds in the low energy regimes of string theories. In particular the emphasis is on the general study of exotic phenomena such as positive acceleration and gravitational bounces. We generalize the usual Hawking–Penrose cosmological singularity theorems to higher–dimensional spacetimes and discuss their implications for time–dependent solutions in supergravity theo...

We study the cosmological evolution of a D3-brane universe in a type 0 string background. We follow the brane-universe along the radial coordinate of the background and we calculate the energy density which is induced on the brane because of its motion in the bulk. We find that for some typical values of the parameters the brane-universe has an inflationary phase.

We describe a scanning mirage microscope system that uses a diode probe laser. The sample is raster scanned using X-Y motorised microstepping stages under an Ar+ pump beam to give two dimensional scans and depth profiles. The results for a test sample are given and are compared to that obtained by scanning using a conventional large photoacoustic (PA) cell.

We use compact D = 4, N = 1, Type IIB orientifolds as a testing ground for recent ideas about precocious gauge coupling unification and a low energy string scale. We find that certain such orientifolds have the interesting property that gauge couplings receive moduli-dependent corrections which mimic the effect of field theoretical logarithmic running. The effective cut-off scale for the logari...