3. Electronic Theses and Dissertations (ETDs) - All submissions
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Item The affective black experience: struggles with conformity for young black professionals in corporate South Africa(2017-09) Bokala, Kutlwano TlameloSouth Africa’s democratic transition was cultured by, amongst others, the mythical ideology of Rainbowism. Rooted in happiness and the promises thereof, the renowned national metaphor was utilised by the state to radically shift the country’s narrative around nationhood towards a shared understanding of identity, belonging, citizenship, and diversity. Today, the influence of Rainbowism within state-led efforts towards social change has slowly deemed under much public scrutiny. Persistent poverty, inequality and violence have fostered the emergence of, what many are calling, an “End of the Rainbow” discourse. As integral and lurid entities within post-apartheid nation-building, black youth and institutionalised spaces have affected and been affected by the shortcomings of Rainbowism. Their shared history and intersecting significance in fuelling collective action amongst South Africans have been well depicted in recent times where youth-led movements have highlighted the inequality and unhappiness that exists in institutions spaces like the university. However, little mention has been made about how black youth are making sense of institutional life within spaces like the workplace, against the backdrop of promised happiness. Through the conversations had with eight young black professionals, this research report centres Rainbowism as a project of happiness that governs institutional life for black youth in South Africa. Happiness is revealed as a dominant discourse operating along axes of power that shape ‘happy’ employees based on various forms of corporeal differentiation.Item The eyes of the naked: what do the eyes of the naked see?(2018-11) Hermanus, LithaProtest literature is dead! Modify it or kill it, said many, including the likes of Professor Njabulo Ndebele and Justice Albie Sachs. At the dawn of the South African democracy, the latter is famously reported to have requested that, at the very least, the genre be sent into a five-year coma (Plummer, 1998). At its height, protest literature was criticised for its lack of creative depth and complexity. A ‘go-to’ for many African writers, it became too ubiquitous. Most of the genre’s authors produced works that were said to suffer from too much sameness. Their white characters were often predictably and typically oppressive, and their African ones were necessarily good. Among other recurring themes, existed political turmoil, violence, death and communities engaging in politically-charged funerals (Lockwood, 2008). Themes did not venture much beyond the struggle against apartheid. It was argued – by Professor Ndebele and others – that a plethora of other themes were part of the South African human experience and they also warranted exploration in literature. This Masters in Creative Writing work, which is comprised of a novel and a complementary reflexive essay (titled The Eyes of the Naked: What Do The Eyes of the Naked See?), explores the notion that, despite the end of apartheid, the conditions that gave rise to protest literature endure. There remains much to protest. There was plenty to protest before the advent of apartheid. Thus, in the essay, the novel The Eyes of the Naked is positioned in the South African canon between a seminal protest literature novel in Mongane Serote’s To Every Birth Its Blood and a pivotal post-apartheid literature text in Zakes Mda’s Ways of Dying. In all three novels there is a colonial thread that traverses epochs. It is suggested that The Eyes of the Naked is a reimagining of protest literature. However, this new variety unequivocally aspires towards complexity and depth. In the novel, protest is located in myriad themes that have their roots in the colonial (and apartheid) experience. These are themes such as civilian violence/crime; love; sexuality; filial disconnection; cultural deracination; masculinity/femininity; the migrant labour system; racism/xenophobia/revolution vs. terrorism. In the end, however, one must submit that The Eyes of the Naked is not classic protest literature. It is a revival of it that seeks to address, with creative depth and complexity, and through a host of other themes, the unrelenting subjugation of Africans in a land that is their home – on soil which most of their feet have never left.Item Item Experiences of unemployment, the meaning of wage work: the dilemma of wage work among ex-gold mineworkers in the Free State Goldfields(2018) Sefalafala, Thabang MasiloThe thesis explores experiences of unemployment to understand the meaning of wage work. This ethnographic research focuses on the everyday lived experiences of unemployed ex-mineworkers in their local contexts. Through personal narratives of men laid off from the dying Goldfields of the Free State (previously called the Orange Free State (OFS), it aims to explicate the powerful moral effects of wage work in a context of pervasive joblessness. Ex-mineworkers affirmed their commitment to wage work as the only way in which security, respect, pride, and dignity can happen in society. Yet, increasingly, in South Africa and indeed across the world, wage work can no longer fulfil those values and its traditional promise. The findings illuminate how unemployment had a profound impact on ex-mineworkers’ sense of self and their place in their homes and communities. They suffer stigma, diminished sense of masculine confidence and negative self-perceptions. The thesis describes the ways in which unemployment was experienced as economic insecurity, social insecurity, and psychological distress. However, I argue that these impairments are only symptoms of a much deeper problem, that is, they experienced a deep moral unease at being unemployed. These impairments do not produce deleterious effects on the unemployed merely because they cause poverty, social uncertainties, and psychological distress, which of course are important, but because a particular moral regulation has lost hold over individuals. The thesis argues that unemployment produced deleterious effects on the unemployed because it occasioned the abrupt disruption of, and loss of shared collective moral values without the immediate provision of an alternative collective moral order in place of the old. As such, unemployment is experienced as loss. Ex-mineworkers attempted to overcome the three impairments through a combination of livelihood strategies. Strategies included standing by the side of the road (men by the side of the road), collecting scrap metal for recycling and remittances. They often inadequately benefitted (indirectly) from various state grants. The livelihood activities they undertook were seen as humiliating and driven by desperation and they were unable to facilitate and secure sustainable and predictable sources of economic security or new forms of social status and dignity. With the above in mind, ex-mineworkers imagined the positive impact that a Basic Income Grant (BIG) or an unemployment grant would have in reducing the insecurities (economic, social, and psychological) of the unemployed. They framed grants as ‘handouts’ which while reducing insecurities, cannot, ultimately, substitute wage work and the values tied to it. They preferred employment and jobs over non-wage forms of income distribution. But this raises a policy dilemma; What happens when full employment becomes impossible? If job creation fails, how do we explain the continued commitment to wage work as the central medium of what it means to live a productive life? I argue, the answer lies not only with respect to the economic benefits tied to jobs, but rather, a deeper historical sociological factor, which is the moral status of wage work in society. The moral status and commitment to wage work, not only makes wage work the only perceived viable way of attaining livelihoods, a meaningful life, masculine status etc., but it also hegemonically blinds the unemployed, policy makers and analysts to imagine possibilities of decent life outside wage work.Item Laser shock peening in friction stir welded joints with lack of penetration defects(2016) Leering, Mitchell PatrickThis experimental work was conducted in order to assess the influence of the application of Laser Shock Peening (LSP) to Friction Stir Welded (FSW) joints. LSP has the ability to potentially recover the reduction in joint mechanical properties that arose due to the presence of a common FSW defect known as Lack of Penetration (LOP). The material used throughout this study was 3 mm thick AA6082-T6 Aluminium. This specific material was selected due to its weldability and common use in the manufacturing of aircraft structures. A 20 mm diameter, spiralled profile shoulder and 5 mm diameter, tapered, three facetted pin was used in the manufacturing of the FSW joints. Experimental assessment and optimisation of the FSW parameters window consisted of the varying the tool rotational speed from 630 to 1600 RPM, at five increments and the feed rate from 200 to 600 mm/min, 200 mm/min intervals. The joints were assessed on the overall quality, microstructure, ductility and static strength. The parameter combinations produced joints with ultimate tensile joint efficiencies which ranged from 48% to 74% that of the base material. The initial study showed that higher welding rates, typically associated with low feed rates, resulted in the highest quality joints. This was attributed to the sufficient thermal softening of the material during welding. The increased welding temperatures improved the joint formation, material flow and mechanical properties. Due to the elevated welding temperatures and material flow, substantial flash formation was observed on all joints manufactured with a welding rate of 5 rev/mm and higher. These results formed the foundation of the multi-objective optimisation in order to determine the most suitable parameters for this welding configuration. The optimisation simulation determined the optimum parameters to be, a tool rotational speed of 1433 RPM, feed rate of 196 mm/min and a welding rate of 7.3 rev/mm. Due to the fixed gearing of the CNC FSW machine the required tool rotational speed could not be achieved, thus, all FSW completed after the optimisation was completed at 1600 RPM, 200 mm/min and 8.00 rev/mm. This parameter combination produced a joint of high structural integrity, high ductility and with no visual sign of internal voids, defects or lack of penetration. The performance of the defect free joint formed the foundation of the characterisation of the influence of intentionally introduced LOP defects. LOP was defined as a pre-initiated crack which formed at the root surface during the fabrication of a FSW joint. Controlled and consistent LOP was introduced into the joints, manufactured with welding parameters of 1600 RPM and 200 mm/min, by offsetting the welding tool in combinations of the normal and lateral directions relative to the joint line. The defects originated at the root surface and extended at various lengths through the thickness of the joints due to the numerous offsets. The defects lengths ranged from a few microns to as much as 954.5 μm. A number of defects affected as much as 43% of the joint thickness. The presence of the defects negatively affected the joints structural static strength by as much as 9% to 27% (dependent on the size of the defect) and dynamic fatigue life of as much as 36%. Laser Shock Peening (LSP) is a novel post manufacturing technique, which has been used to introduce compressive residual stresses within the near surface of the metallic components. A LSP processing was completed without a protective ablative coating (LSPwC), at a wavelength of 1064 nm and pulsed nano-second laser at 10 Hz. The characterisation of varying the laser power intensity and processed coverage to the base of FSW AA6082-T6 Aluminium was completed through extensive parameter window exploration. Factors such as the quality of the energy delivery, sample deflection, strain hardening, penetration of effects through the FSW joint thickness and the improvement of the fatigue life of the base material were used to define the appropriate parameters. A multi-objective optimisation strategy was implemented in the attempt to fully explore the regions between tested parameter combinations; to provide an optimum set of LSP parameters which would be used in combination of the optimum FSW parameters. The simulation predicted two optimum sets of parameters dependent on the desired outcome of either maximising component fatigue or LSP depth of penetration effect. Due to the nature of this research requiring both fatigue and penetration depth, a parameter set was selected based on parameters that would theoretically provide the maximum for both desired outcomes. The optimum power intensity and coverage was specified as 3.33 GW/cm2 and 1067 spots/cm2. The optimum parameters of each process was combined in an attempt to recover the drop in fatigue life of the joints due to the presence of the LOP defect. LSP was capable of altering the near surface residual stress states of approximately 100 MPa tensile to -150 to -200 MPa compressive across the three measurement ranges. It was found that LSP had minimal effect on the fatigue life of the components in the low cycle fatigue due to the applied stress relaxing the introduced stress thus having minimal effect on the life of the joints. LSP was found to increase the fatigue life of the non-defective joints by as much as 68%. LSP showed a life improvement of approximately 20% in a joint which had a defect length of roughly 175μm. After the application of LSP the samples in the low cycle fatigue tended to fail at a closed cycles to failure as the non-defective unpeened samples. Application of a LSP to a FSW was found to shift the fracture position of the flawed components from the region of the defect to that of the Heat Affected Zone (HAZ) on the advancing side of the weld. It is suggested that, the shift in fracture position was due to critical relocation of the tensile stress during LSP into the HAZ on the advancing side. The results did not conclusively show that LSP was capable of recovering the effects of the LOP but was plausible that it could possible. This has been said due to some samples exhibiting an increase and due to the change in location of the fracture position.Item A preliminary description of South African Sign Language syntax(2017) Wright, DonovanThis study is a preliminary investigation into the syntax of South African Sign Language. Utilising narrative data within a case study approach, signing is observed and analysed in terms of Radical Construction Grammar. An emphasis is placed on signs as form-meaning pairings, in which information of form is drawn from previous research on the phonology and morpho-syntax of signed languages. Meaning is explained within the same sphere, drawing on established literature regarding meaning in signed languages – with the addition of Mental Space and Conceptual Blending theories. The aim is to describe the signing elicited as in-depth as possible while covering a broad number of relevant aspects. The efficacy of Radical Construction Grammar as a theoretical framework in signed language is also considered. Results include descriptions of different construction types and a holistic view of signing. Schemas are proposed for common constructions, and Radical Construction Grammar is posited as a viable alternative to a traditional understanding of syntax.Item Teachers’ perceptions of school-based support teams in the Johannesburg East School District(2015) Schneiderman, FarrynThe aim of this research study was to explore how teachers in a sample of primary schools in the Johannesburg East school district of Gauteng perceive the school-based support teams (SBST) at their schools. These support teams are supposed to be existing structures within public schools in South Africa according to the policy outlined in Education White Paper 6 (Department of Education, 2001). Teachers in South African government schools often face considerable challenges in the implementation of inclusive education. These include catering to the individual needs of all learners within classrooms that contain a large number of learners. A mixed-method exploratory descriptive design was used to carry out the exploration of this study. Five government primary schools in the Johannesburg East school district participated in this study and there were fifty-four educators that voluntarily completed a questionnaire that consisted of both open- and closed-ended questions. Data from the questionnaires were analysed by using frequency and descriptive analysis, as well as thematic content analysis. Results from this questionnaire indicated that the majority of the respondents have a positive outlook on the school-based support team approach and would like this approach to continue within their school. They do however require additional support from the district support team and would need assistance from both the district and school-based support teams in order to constructively deal with specific barriers to learning. This will improve the collaborative support and emotional well-being of the educators, thereby improving the quality of education provided to the learners.Item A geometallurgical strategy for improving ore quality and mineral processing efficiency at Kansanshi Mine in Zambia(2016) Beaumont, ChristopherThe Kansanshi mine is located in north-western Zambia. It is a copper and gold bearing, vein hosted, structurally controlled, ore deposit, which is exploited using conventional open pit mining methods. A series of highly complex mineralogical suites have formed through the interaction of the in-situ geological, weathering and oxidation processes. Some of these mineralogical suites are extremely difficult for effective extraction of copper and gold. Currently ore is classified into 22 different quality categories using a system called “Mat_Type”. Only the “best quality” ore is directed to the metallurgical process plant, while the remaining “poor quality” ore is directed to long term stockpiles. These stockpiles are unlikely to be processed until the end of the life of mine despite containing metal quantities of significant value. A systematic investigation of Kansanshi’s mine value chain was carried out to determine if this value could be realised sooner. It was found that, due to a lack of integration between technical silos that form the mine value chain, the Mat_Type system does not take due consideration of geological, mineralogical nor metallurgical processes. Ore quality control factors are incorrect and economic data to determine suitable cut-off grades is both outdated and applied in an inappropriate manner. As a result 12 of the 22 Mat_Type ore categories are unnecessary, while a further six categories are inaccurately defined, leaving only four categories that can be considered to be correct. It is because of these errors, that so much ore is being directed to long term stockpiles. Through the research study presented in this report it was found that five key factors determine an effective ore classification system for Kansanshi mine. These factors can be defined as: Spatial distribution of mineralogical relationships between in-situ geological, oxidation and weathering domains; The impact of mineralogical groupings on copper recovery in each metallurgical process; The size, statistical distribution, range and accuracy of available data sets; The application of appropriate economic factors in the mineral resource to mineral reserve conversion process; and, The practicality of overcoming physical constraints at various stages of the mining process A more appropriate geo-metallurgical ore classification system can be developed that will consider the above listed factors. Three mineralogical groupings naturally exist in the deposit. Using total copper and acid soluble copper assay data, these mineralisation categories can be defined by a specific range of oxidation ratio. These ranges can be listed as: Primary copper sulphide minerals, with oxidation ratio < 0.1 ; Secondary copper sulphide minerals, with an oxidation ratio between 0.1 to 0.8; and , Primary copper oxide minerals, with an oxidation ratio between 0.8 to 1.0. Each mineralogical grouping can be assigned to a specific metallurgical process. Further subdivisions of these groupings can be made based upon economic grade ranges and appropriate metallurgical quality control factors which are linked to a specific metallurgical process. By implementing the proposed geo-metallurgical ore classification system, 12 of the erroneous ore categories in the Mat_Type system can be removed. The remaining 10 categories would be accurately and consistently defined. This will lead to a significant reduction in the quantity of ore directed to long-term stockpile, thereby releasing previously lost value. The new ore classification methodology proposed would be supported by a systematic process to manage regular, periodic updates, based on new data and developments in technical understanding across all functional areas of the mine value chain. A continued dialogue and sharing of knowledge between the main technical silos is critical when promoting a robust and integrated ore classification system. Such a system has the potential to remain relevant throughout the life of Kansanshi mine.Item The industrial viability and characterization of WC-Co alloys produced by acid leaching and recycling techniques(2016) Freemantle, Christopher StuartIn the current study, the well-established zinc recycling process and a prototype acetic acid recycling plant were successfully employed to recycle cemented tungsten carbide scrap material for re-use as production powders. The recycled materials were studied and compared to new materials at each stage along the cemented carbide manufacturing route, in a production environment. Analysis of by-product materials from the zinc recycling process revealed that while some by-product material can be readily converted into powder using the supplementary acetic acid method, the rest is most efficiently recovered by using a second zinc recycling run and by controlling the size and purity of the scrap material introduced into the process. Various analytical techniques, including the novel use of proton induced x-ray emission studies were used to characterize the materials in both the powder and sintered form. The analyses revealed that the recycled materials possessed superior microstructural homogeneity than new materials, and greater than 99% purity. Studies of milling behavior and slurry rheology revealed no adverse effects of using recycled materials, provided that the slurry properties prior to powder spray drying were appropriately controlled. Polymer binder integrity remained intact despite the longer milling times associated with the use of recycled materials, and the superior slurry stability of recycled materials was demonstrated. The flow behavior and powder rheology of the spray dried powders was found to depend on the precursor slurry rheology and particle grain size. This was controlled predominantly by the formation of a sufficient yield stress to produce ideal, dense granules for greater ease of manufacturing, in both new and recycled powders. The acetic acid recycling technique can be used as a complimentary recycling process to the existing zinc recycling process, and can produce useable recycled material at low cost.Item Melrose House Museum: Memory and Nostalgia the next stage of #RhodesMustFall(2018) Lindeque, MelissaThe broad knowledge field of Melrose House located in 20th century South Africa explores the notion of #RhodesMustFall movement probing into the complex relationship with colonial and apartheid heritage in contemporary South Africa, do they still fit within a democratic genre? #RhodesMustFall movement challenges decolonising the South African education system arguably contesting memories found in daily South African life questioning the need of 20th century museums, statues and sites. Melrose House Museum, located in Pretoria, is a 20th century house museum with a 19th century collection. Utilising qualitative exploration of Melrose House Museum through concepts of memory, nostalgia and trauma I chart the relationship between #RhodesMustFall and Melrose House museum. The role of 20th century museums in South Africa is establishing and preserving South African history adding historical and monetary value to South Africa. This research falls within the scope of the aftermath of #RhodesMustFall questioning if museums are next on the chopping block adding to the relevance and need of Western exhibition in a postcolonial South Africa.