This research examines the role of Private Capital Flows (PCF) and Financial Deepening in the economic growth of South Africa. Using secondary data obtained from the South African Reserve Bank and the World Bank online databases for the period 1990 to 2015, we examine the relationship between these three variables using the Autoregressive Distributed Lag (ARDL) bounds testing procedure. The causal relationship between the variables is further investigated using the Granger Causality test. Where previous studies mainly focus on investigating the relationship between capital flows and economic growth; and that of financial deepening and economic growth in South Africa independently; this study looks at the interrelationship between these three variables. Contrary to our expectations, the findings from the research suggest that there is no significant long run relationship between these variables in South Africa; however we found significant unidirectional short run causal relationships between the variables. The study established that in the short run, economic growth granger causes private capital flows; financial deepening granger causes private capital flows and that economic growth granger causes financial deepening. These findings imply that putting in place policies that encourage economic growth will lead to improvements in both PCF and financial deepening in the short run. In turn, improvements in financial deepening will also foster improvements in PCF in the short run. The results, policy implications, and future research are discussed.

In order to estimate the oxygen fugacity of Hawaiian lavas I have measured the ferric/ferrous ratios of samples from the 1984 eruption of Mauna Loa volcano and from the ongoing (1983-2017) Puu Oo eruption of Kilauea volcano. Fifteen samples were studied from the 21 day Mauna Loa eruption and 86 samples, erupted between 1983 and 2004, of the 34 year long Kilauea eruption. Both studies show that, in order to obtain reliable estimates of oxygen fugacity when, where, and how basaltic lava is sampled is of critical importance. Water-quenched lavas and spatter sampled at, or near vents, are less oxidized than water-quenched samples taken from open flow channels several kilometers away from the vent, or from slowly-cooled solidified flows. Additionally, samples of water-quenched lava traveling in lava tubes are less prone to oxidation than lava flowing in open channels, with oxygen fugacities similar to those of near vent quenched samples. The oxidation state of the rapidly quenched near vent or lava tube samples is at or below magnetite-wüstite (MW). This contrasts with the oxidation state of previously reported values for Hawaiian lavas, which are closer to fayalite-magnetite-quartz (FMQ) or nickel-nickel oxide (NNO). From this I conclude that the initial oxygen fugacity of Hawaiian parental magmas is close to MW and not FMQ, and that previous estimates of the oxidation state of Hawaiian magmas, based on data from solidified lava flows, were too high. This implies that the plume source of both Mauna Loa and Kilauea magmas is also close to MW, but not as reduced as the mantle source of mid-ocean ridge basalts.

Free-surface modelling (FSM) is a highly relevant and computationally intensive area of study in modern computational fluid dynamics. The Elemental software suite currently under development offers FSMcapability, and employs a preconditioned GMRES solver in an attempt to effect fast solution times. In terms of potential solver performance however, multigrid methods can be considered state-of-the-art. This work details the investigation into the use of AlgebraicMultigrid (AMG) as a high performance solver tool for use as black box plug-in for Elemental FSM. Special attention was given to the development of novel and robust methods of addressing AMG setup costs in addition to transcribing the solver to efficient C++ object-oriented code. This led to the development of the so-called Freeze extension of the basic algebraic multigrid method in an object-oriented C++ programming environment. The newly developed Freeze method reduces setup costs by periodically performing the setup procedure in an automatic and robust manner. The developed technology was evaluated in terms of robustness, stability and speed by applying it to benchmark FSM problems on structured and unstructured meshes of various sizes. This evaluation yielded a number of conclusive findings. First, the developed Freeze method reduced setup times by an order of magnitude. Second, the developed AMG solver offered substantial performance increases over the preconditioned GMRES method. In this way, it is proposed that this work has furthered the state-of-the-art of algebraic multigrid methods applied in the context of free-surface modelling. / Dissertation (MEng)--University of Pretoria, 2011. / Mechanical and Aeronautical Engineering / unrestricted

Cette thèse traite par simulation numérique les écoulements turbulents compressibles avec transferts de chaleur, en relation avec les applications moteurs-fusées. Elle concerne, plus particulièrement, les systèmes de refroidissement des chambres de combustion. Le fluide refroidissant circule dans un état supercritique (haute pression et basse température) dans des canaux millimétriques, entourant la chambre de combustion. Ces problèmes font appel à une physique assez complexe et mettent en jeu un couplage fort entre les aspects compressibles et les transferts thermiques, en plus des phénomènes liés à la thermodynamique supercritique. D’un point de vue numérique, deux solveurs spécifiques ont été utilisés dans le cadre de cette thèse. Il s’agit, d’une part, du code CHOC-WAVES développé au CORIA pour la partie compressible et onde de choc et, d’autre part, le code PPMBFS développé à l’Université de Pennsylvanie (USA) pour les applications supercritiques et avec une thermodynamique variable. Sur le plan de la modélisation physique, l’approche LES a été utilisée, en appui des simulations DNS. Dans ce contexte, un modèle de sous-maille thermique, pour la prise en compte du Prandtl turbulent variable, a été intégré et validé. Les résultats obtenus, dans le cadre des LES et DNS d’un canal supersonique refroidi, ont permis de mieux analyser les corrélations aérothermiques ainsi que les structures cohérentes présentes au sein de cet écoulement. En particulier, il a été montré les limites de l’hypothèse de l’Analogie Forte de Reynolds (SRA) dans le cas d’écoulements fortement anisothermes, et le rôle joué par les structures tourbillonnaires dans l’accentuation des transferts pariétaux. La problématique des gaz réels a été ensuite examinée dans le cadre d’un canal industriel (en l’occurence EH3C). Cette étude a permis de mettre en évidence les difficultés (à la fois numérique et physique) liées à ce type d’écoulement. Les différentes investigations ont permis de fournir des informations utiles, notamment en ce qui concerne la phénoménologie des structures cohérentes et les différentes corrélations aérothermodynamiques. / This research deals with the numerical simulation of compressible turbulent flows with heat transfers, applied to rocket engines. It relates more particularly the cooling of combustion chambers, in which a fluid flows in a supercritical state (high pressure and low temperature) inside millimeter channels. These problems involve complex physical phenomena and coupling between compressible aspects and heat transfer phenomena as well as supercritical thermodynamics. From a numerical point of view, two specific solvers have been used in the context of this thesis. The first code (CHOC-WAVES) has been developed in the CORIA lab for compressible flows and shock waves. The second one (PPMBFS) has been developed at the Pennsylvania University for applications with supercritical thermodynamics variables. In terms of physical modeling, the LES approach has been widely used in support of DNS. In this context, a thermal subgrid model using a variable turbulent Prandtl number has been integrated and validated. A supersonic cooled channel has been simulate dusing both LES and DNS techniques and its results have been carefully analysed through the aerothermics correlations and coherent structures. In particular, it has been shown that the Strong Reynolds Analogy hypothesis (SRA), in the case of a strongly anisothermal flow is not valid anymore. The wall heat flux had an impact on the coherent structures. The issue of real gases was then examined through the industrial channel flow simulation (EH3C). This study has high lighted the difficulties (both numerical and physical) associated with this type of flow. The various investigations have provided useful information, especially regarding the phenomenology of coherent structures and various aerothermodynamics correlations.

This research investigated the ability of current earnings and cash flows to predict future cash flows and future share prices. The investigation was conducted used financial information of JSE listed companies over a period between 2001 and 2011. The objectives of the research were to establish the predictive ability of current earnings and cash flows on future cash flows and share prices. This study was motivated by the findings of Kim and Kross (2005) where they consolidated the earlier findings by Collins et al. (1997) and Dechow et al. (1998).It was predetermined that the study would add to the body of knowledge in financial statements analysis and the application of earnings and cash flows as the predictive financial variables, Earnings are regarded as an essential measure of company of company‘s performance and cash flows from operations as a measure of the company‘s ability to generate cash flows from their operations. It was noted that investors do study and analyse these financial elements when investment decisions are made (Higgins, 2009; De Fond and Hung, 2003).It was found that earnings did not have the predictive ability on future cash flows but proved to possess high predictive power over future share prices. The results were not in agreement with the previous studied on the same subject. The average of R-square on current earnings ability to predict future cash flows were R2=0.27 and 0.38 in the long run and short run, respectively. The predictive ability on future share prices were R2=0.44 and 0.54 in the long and short run, respectively. Current cash flows on the hand indicated low predictive ability on future share price where the average R2=0.24 and 0.33 in the long and short run respectively. The predictive ability on current cash flows over future cash flows proved to be higher, which was not consistent with the previous researchers. The average R2 were 0.44 and 0.46 in the long and short run. It was noted that these financial elements proved to possess higher predictive abilities in the short run. / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted

In this thesis, we develop a physical understanding of the effects of viscosity and geometry on the dynamics of interfacial flows in drops and bubbles. We first consider the coalescence of pairs of conical water droplets surrounded by air. Droplet pairs can form cones under the influence of an electric field and have been observed to coalesce or recoil depending on the angle of this cone. With high resolution numerical simulations we show the coalescence and non-coalescence of these drop pairs is negligibly affected by the electric field and can be understood through a purely hydrodynamic process. The coalescence and recoil dynamics are shown to be self similar, demonstrating that for these conical droplet pairs viscosity has a negligible effect on the observed behavior. We generalize this result to the coalescence and recoil of droplets with different cone angles, and focus on droplets coalescing with a liquid bath and flat substrate. From the simulations of these droplets with different cone angles, an equivalent angle is found that describes the coalescence and recoil behavior for all water cones of any cone angle. While viscosity is found to negligibly affect the coalescence of conical water drops, it plays a key role in regulating the coalescence process of bursting gas bubbles. When these gas bubbles burst, a narrow liquid jet is formed that can break up into tiny liquid jet drops. Through consideration of the effects of viscosity, we show that these jet drops can be over an order of magnitude smaller than previously thought. Here, viscosity plays a key role in balancing surface tension and inertial forces and determining the size of the jet drops. Finally, we investigate the drainage of surfactant free, ultra-viscous bubbles where surface tension serves only to set the initial shape of the bubble. We use interferometry to find the thickness profiles of draining bubble films up to the point the of rupture. A theoretical film drainage model considering the balance of viscous and gravitational stresses is developed and numerically computed. The numerical results are found to be consistent with the experimentally obtained thickness profiles. In this work we provide insight into the role of viscosity in the outlined interfacial flows. The results of this thesis will advance the understanding of drop production in clouds, the marine climate, and the degassing of glass melts.

Passive gains are becoming essentials with the introduction of new buildings thermal regulations. To optimize such gains, districts ground plan have to be based not only on urban consideration, but on bioclimatic considerations as well. Bioclimatism first purpose is to take advantage of the local climate and modify it if needed to obtain as much passive gains as possible for the building performance and interior comfort to be improved. The second one is to create a good exterior climate and pedestrian comfort. In fact, the first total factor of energy savings is the density of buildings. It is then of the greatest importance to attract population downtown by offering comfortable exterior spaces that can compete with more rural areas. This thesis will then focus on the wind flows impact on the outdoor and pedestrian comfort. To conduct this research, some points need to be clarified. First, what is the optimum scale to study and adapt the climate to our needs? The scale of the district had several advantages compared to a city or a dwelling scale: it is a representative city sample, its scale is reduced enough for limited data quantity to allow the evaluation of the development decisions impact on the building performance, it has a reduced number of decision makers diminishing the decision complexity and a certain amount of freedom remains allowing to adapt at best the local climate to the project needs. Second, who will be the actors of the bioclimatic conception during the project? The planner and the conception team are ubiquitous during a district conception phase and have a central position in the decision making. Hence, it is with them that the integration of the bioclimatic approach will be the more effective. Third, the success of the thesis is based on the capacity to make the heat engineers and the conception team exchange on the subject of bioclimatism. As a result, it had to be realized in a company possessing at least heat engineers and one of the conception team professions. The French company SCE, part of the Keran group, offered such environment with urban planning and energy and building activities. The process of the study was the following. A benchmark was made on the existing software that could be use by the company to realize pedestrian and outdoor comfort analysis. Then, an outdoor comfort study was made on a district construction project in the French town of Cancale. The project buildings impact on one another was analyzed. For each high frequency wind incidences, simulations were run first in 2D dimension and second in 3D dimensions. Based on the wind speed values inside the district zone calculated by the software, discomfort zone had be highlight. According to the level of discomfort, the installation of different wind breakers type was recommended.

The separation of submicron particles suspended in gaseous flows is a problem of great importance and is the subject of sustained research efforts. This is motivated by several challenges presented by modern science and technology requiring high separation efficiencies for submicron particles.Continuous acoustic particles separation is a novel technique based on the acoustophoresis phenomenon, in which a particle within an acoustic field is manipulated using acoustic forces on its surface. This technique has the potential to overcome some of the limitations of common techniques for the separation of submicron particles, as well as performing advanced tasks such as sorting particles according to their size or density.In this thesis, the separation of submicron solid particles suspended in air is investigated experimentally, with a focus on the effect of key design parameters (acoustic, flow, geometry) on the efficiency of the process. A simple method based on laser light scattering was also used to provide qualitative information on the particle number density as a function of position in the channel. This technique allowed to quickly investigate the effect of a wide range of parameters on the acoustic separation efficiency including the pressure amplitude, the frequency of the standing wave, the average flow velocity and the parallelism of the channel walls.   The results demonstrate conclusively that acoustic manipulation is possible for submicron particles and that the acoustic force scales following the trends expected from theoretical models developed in the continuum regime. From the size of the particles used it however follows that the observed separation is the result of transition regime acoustophoresis, with a Knudsen number on the order of 0.2. / <p>QC 20150522</p>

This article describes a method to analyse retail trade flows among competing retail centres. A case study of three nearby communities in the Southeastern United States is used to demonstrate the application of the technique. Results of the case study and their implications are discussed.

In 1960, Kīlauea volcano in Hawaii erupted, destroying most of the village of Kapoho and forcing evacuation of its approximately 300 residents. A large and unprecedented social science survey was undertaken during the eruption to develop an understanding of human behavior, beliefs, and coping strategies among the adult evacuees (n = 160). Identical studies were also performed in three control towns located at varying distances from the eruption site (n = 478). During these studies data were collected that characterized ethnic grouping and attitudes toward Hawaiian cultural issues such as belief in Pele and two lava flow mitigation measures-use of barriers and bombs to influence the flow of lava, but the data were never published. Using these forgotten data, we examined the relationship between Hawaiian cultural issues and attitudes toward the use of barriers and bombs as mitigation strategies to protect Kapoho. On average, 72% of respondents favored the construction of earthen barriers to hold back or divert lava and protect Kapoho, but far fewer agreed with the military's use of bombs (14%) to protect Kapoho. In contrast, about one-third of respondents conditionally agreed with the use of bombs. It is suggested that local participation in the bombing strategy may explain the increased conditional acceptance of bombs as a mitigation tool, although this can not be conclusively demonstrated. Belief in Pele and being of Hawaiian ethnicity did not reduce support for the use of barriers, but did reduce support for bombs in both bombing scenarios. The disparity in levels of acceptance of barriers versus bombing and of one bombing strategy versus another suggests that historically public attitudes toward lava flow hazard mitigation strategies were complex. A modern comparative study is needed before the next damaging eruption to inform debates and decisions about whether or not to interfere with the flow of lava. Recent changes in the current eruption of Kīlauea make this a timely topic.