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There’s another story here

  • Authors: Nkosi, Lindokuhle
  • Date: 2018
  • Subjects: Creative writing (Higher education) -- South Africa , South African fiction (English) -- 21st century , Short stories, South African (English) -- 21st century
  • Language: English
  • Type: text , Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10962/63065 , vital:28360
  • Description: Written in fragments and combining fiction and narrative non-fiction, this novella explores how South Africa's history of violence and current violence against women affects and influences how women relate to each other. Based in the knowledge that our memories and behaviours are linked to the experiences of our ancestors via our bodies, I engage what our violent history and the disappearing myths that are still embedded in our bloodstream mean for life today. Drawing on the experiences of several generations of women in my family, current affairs and the lives of women close to me, my novella picks at the fragile things that hold us together. I take influence from the prose poetry in Claudia Rankine’s Citizen, and the use of fragmentation, myth and biography in Lydia Yuknavitch’s A Chronology of Water and Lily Hoang’s A Bestiary, and use an amalgam of genres to ask how we hold each other; how we breath, create, love and dream.
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  • Date Issued: 2018

Thermoluminescence of annealed synthetic quartz: the influence of annealing on kinetic parameters and thermal quenching

  • Authors: Dawam, Robert R , Chithambo, Makaiko L
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/110050 , vital:33218 , https://doi.org/10.1016/j.radmeas.2018.06.004
  • Description: The thermoluminescence of synthetic quartz annealed at various temperatures up to 900 °C is reported. Glow curves measured at 1 oCs−1 following beta irradiation to 40 Gy from a sample annealed at 500 °C and from an unannealed one consist of a prominent peak at 70 °C and secondary peaks at 110, 180 and 310 °C. In comparison, the glow peak from the sample annealed at 900 °C consists of three peaks but with the main peak at 86 °C and other lower intensity peaks at 170 and 310 °C. Kinetic analysis was carried out on the main peak only in each case. The order of kinetics of this peak was determined to be first order using various methods. The activation energy was evaluated as an average of 0.90±0.02eV for the unannealed sample and the one annealed at 500 °C. However, when the synthetic quartz is annealed at 900 °C, the activation energy decreases to 0.65±0.02eV. The main point of interest however concerns thermal quenching. It was noted that for the sample annealed at 500 °C as well as the unannealed one, the maximum intensity of the main peak decreases with heating rate. This phenomenon is associated with thermal quenching. When the same experiment is carried out using quartz annealed at 900 °C and irradiated to the same dose, namely 40 Gy, the intensity increases with heating rate. This would imply that this sample is not affected by thermal quenching. Using the notion that the radiative and non-radiative recombination routes are competitive, we repeated the experiment using a low dose of 3 Gy. In this case, the intensity decreased with heating rate showing that the process can be tuned. The activation energy for thermal quenching for the samples annealed at 900 °C, 500 °C and unnannealed one was found as 0.65±0.02eV, 0.82±0.02eV and 0.95±0.06eV. Evidently, annealing affects recombination processes in synthetic quartz.
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  • Date Issued: 2018

Thermoluminescence of the persistent-luminescence phosphor, BaAl2O4: a stuffed tridymite

  • Authors: Pandey, A , Chithambo, Makaiko L
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/113048 , vital:33693 , hhttps://doi.org/10.1016/j.radmeas.2018.01.004
  • Description: BaAl2O4 is a stuffed tridymite used as a long-lasting phosphor. The thermoluminescence of BaAl2O4 prepared by solution-combustion is reported. Analysis of the sample using X-ray diffraction shows that it formed as a single phase compound with a hexagonal structure following annealing at 1200 °C. A broad photoluminescence emission band between 300 and 650 nm was detected due to excitation at 248 nm. The phosphor showed a natural TL peak at 102 °C for measurement at 1 oCs−1 and, when beta irradiated to 100 Gy, two broad peaks at 123 and 318 °C also for heating at 1 oCs−1. The analysis of the main glow peak at 123 °C suggests that it is a combination of several collocated peaks, that is, peaks embedded within each other. We resolved four such components labelled peaks 1 to 4. The thermoluminescence decreases with heating rate in a way consistent with thermal quenching whose activation energy was determined as ∼0.65eV using peak 3. Interestingly, this value of the activation energy for thermal quenching for BaAl2O4, a stuffed derivative of silica, is similar to literature values for quartz (a silica), suggesting that the recombination centre in the two cases may be similar.
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  • Date Issued: 2018

Thermoluminescence of α-Al2O3: C, Mg annealed at 1200° C

  • Authors: Kalita, Jitumani M , Chithambo, Makaiko L
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/111030 , vital:33365 , https://doi.org/10.1016/j.nimb.2018.03.003
  • Description: Stimulated luminescence in α-Al2O3:C,Mg has thus far been studied for samples annealed at temperature no higher than 900 °C as can be seen by an examination of the literature. We report the thermoluminescence (TL) features of α-Al2O3:C,Mg annealed at 1200 °C. A glow curve measured at 1 °C/s from the samples annealed at 1200 °C shows eight peaks at 54, 80, 102, 173, 238, 290, 330 and 387 °C. Kinetic analyses show that the peak at 54 °C follows general order kinetics (b = 1.3) whereas the rest follow first order kinetics. The values of the activation energy of the peaks are between 0.77 eV and 1.90 eV and the frequency factors are of the order of 1010–1014 s−1. The intensity of the peaks at 54, 80, 102 and 173 °C increase with heating rate whereas those of the peaks at 238 and 290 °C decrease with heating rate. The decrease of intensity of the peaks at 238 and 290 °C with heating rate is due to thermal quenching whereas the increase of intensity of the peaks with heating rate indicates an inverse thermal-quenching-like behaviour. Interestingly this behaviour is observed only after annealing at 1200 °C. The activation energy for thermal quenching as calculated using the peaks at 238 and 290 °C are (1.02 ± 0.16) eV and (1.33 ± 0.15) eV respectively. Regarding the dosimetric features, the dose response of the peaks at 54, 80 and 102 °C are sublinear within 1–10 Gy and the peak at 54 °C saturates above 6 Gy. In contrast, the response of the peak at 173 °C is sublinear with 1–4 Gy and superlinear between 4 and 10 Gy. The peaks are found to fade at different rates and the rate of fading is also affected by annealing.
  • Full Text: false
  • Date Issued: 2018

The design of a community owned winery in Philippi informal settlement Cape Cape

  • Authors: Steytler, Willem
  • Date: 2018
  • Subjects: Wineries -- South Africa -- Cape Town -- Designs and plans , Wine and wine making -- South Africa -- Cape Town
  • Language: English
  • Type: Thesis , Masters , MArch
  • Identifier: http://hdl.handle.net/10948/39196 , vital:35057
  • Description: The study focuses on Philippi as a particular place and the communities that dwell there. It aims to study the spatial dispositions caused by apartheid and colonialism. The dissertation highlights the inequality of South African cityscapes which is then extrapolated in the conditions that exists on the Cape Flats. A core focus of the study is the way in which architecture might aid the spatial inequality in a post-apartheid South Africa. The first bottle of wine was bottled in South Africa seven years after the Cape had been colonized. This means that the wine industry has always been synonymous of colonialization to a certain degree. Further research reveals that the part of the Cape Flats that is today known as Philippi Township was used for grapevine cultivation by German settlers from the 1830s, but with the advent of the forced removals, the 1950 Groups Area Act zoned that land for the relocation of the non-white community. The community on the Cape Flats experiences a significantly lower quality of life than many of the suburbs in Cape Town. (http://journals.sagepub.com) It can be noted that the areas surrounding Cape Town have an abundance of vineyards owned mostly by a singular demographic with a significantly higher income than those living in the townships. Research has indicated that the ‘terroir’, (climatic and environmental conditions) of Philippi is ideal for grapevine cultivation and there are upwards of 250 hectares of open land. The viticulture industry is one of the biggest sources of income for the Western Cape but the problem lies in the fact that the revenue created is channeled only to an elite group of people. To counteract the repercussions of apartheid many strategies have been implemented by the government; among these is land reform. The physical and spatial nature of this place is investigated to create an architectural viewpoint on the matter. The treatise explores the design of a community-owned winery in the Philippi Informal Settlement and examines how the resultant architecture might address the impaired configuration of the urban make-up while strengthening the sense of identity. The idea is that through leap-frog development locals will plant vineyards in open spaces, making the township a greener space to live in, whilst also generating income for the local inhabitants and allowing for the transfer of knowledge. The use of precedent studies into the nature of building type, site visits as well as site- and precinct investigations were necessary to reach an understanding of the building type and a possible architectural response to the sensitive topic. All research is qualitative using inductive reasoning. Qualtative research is based on observation to gather non-numerical data. Inductive reasoning is reasoning where the premises support the conclusion, which means that the conclusion is the part of reasoning that inductive reasoning is trying to prove. The understanding gained from the above-mentioned methods led to an appropriate architectural response in the form of a design. The design is the conclusion and proposed solution of the treatise.
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  • Date Issued: 2018

Think Piece on Amanzi for Food. Working with Critical Realism to Inform a Situated Learning Framework for Climate Change Education

  • Authors: O'Donoghue, Rob B
  • Date: 2018
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/388136 , vital:68309 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/172215"
  • Description: This study is developed as a think piece which deliberates the problem of transformative human agency in a curriculum setting. Using a critical realism perspective and schematic tools it examines the deliberative framing of an Amanzi for Food teaching garden as an education process for mediating the learning of rainwater harvesting. Working with Bhaskar’s Transformational Model of Social Activity and using expansions of his ‘four-planar social being’ schema and its resolution in his ‘social cube’ model, the study contemplates the framing for a curriculum for the mediation of co-engaged social learning in the contexts of practical work in an agricultural college curriculum setting. In this way the research process is developed as an under-labouring review of the emerging curriculum in search of theory to inform pedagogy for mediating situated processes of transformative social learning.
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  • Date Issued: 2018

Think Piece. Intersectional Resonance and the Multiplicity of Being in a Polarised World

  • Authors: Kulundu, Injairu
  • Date: 2018
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/388037 , vital:68301 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/172212"
  • Description: Understandings of collective learning and change agency often conjure up an image of a particular group or community identifying important concerns and finding the momentum to learn together to address them. In reality, gaining consensus around what issues need to be addressed is a complex process in polarised societies. It requires an attentiveness to different standpoints and experiences of the social dynamics at play, and the ways in which ecological, political, socio-economic and psychic experiences manifest themselves within different contexts, generating disparate and connected views on what is missing and what is needed to create a more just society. This paper asks questions about what it means to learn in-between and through complex and interrelated societal dynamics amongst a community of change drivers. By highlighting the individual, communal and collective learning of a diverse group of change drivers in a very polarised South Africa, we can begin to ask questions about the following: 1) how different embodied experiences or ‘a multiplicity of being’, as referred to in this paper, are essential in the pursuit of a sustainable society; and 2) why we need to learn in ways that can foster a sense of ‘intersectional resonance’ between and amongst change drivers in a polarised world.
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  • Date Issued: 2018

Think Piece: Pioneers as relational subjects? Probing relationality as phenomenon shaping collective learning and change agency formation

  • Authors: Lotz-Sisitka, Heila
  • Date: 2018
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/182787 , vital:43874 , xlink:href="DOI 10.4314/sajee.v34i1.5"
  • Description: This paper deliberates on how relationality is framed in collective learning and change agency formation processes, with an emphasis on green economy and renewable energy learning contexts. The paper is not focused on empirical analysis of relationality in collective learning, but rather probes the phenomenon in order to provide more carefully constituted theoretical and analytical tools for further empirical research. The paper uses references to South African and Danish cases (albeit in slightly different ways), and, through this, it sets out to provide tools for generative insights and research into a recent international policy and strategy process which is bringing national-level Green Economy Learning Assessments (GELA) into being, including one in South Africa. Central to these GELAs is the notion of participatory or relational competence, which appears to be a central feature of collective learning, although this is not empirically analysed in this paper. In case study work undertaken for the GELA in South Africa that focused on South Africa’s major renewable energy development, and in the Samsø Island renewable energy transition case in Denmark, this competence appeared to come into focus in praxis. Interestingly, however, it appeared to come into focus colloquially as a discourse on ‘pioneers’ or ‘champions’, a phenomenon noticed in both the South African and Danish contexts. This paper probes this phenomenon further, especially since it initially appears to be contradictory to the emphasis on participatory and relational competence in the GELA study framework. This is because the concept of ‘pioneer/champion’ appears to highlight individual capabilities rather than collective, relational competences. Yet, on closer inspection, it is indeed the relational competences of the pioneer/champion, who is constituted as a ‘relational subject’ with a key role to play in producing shared relational goods, that appears to be significant to the collective learning and action process. This, as argued in the paper, requires a differentiation of relationism and relational realism. This Think Piece, which thinks with both theory and praxis, therefore offers a possible framework for more detailed empirical studies on relationality in collective learning and change agency formation.
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  • Date Issued: 2018

This is our story: iconography of carved doors and panels in Òyó Palace

  • Authors: Fọlárànmí, Stephen
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/145698 , vital:38459 , https://0-doi.org.wam.seals.ac.za/10.1162/afar_a_00402
  • Description: This saying or prayer is one of the numerous expressions among the Yorùbá about the door and its significance, not only as a physical and important aspect of their architecture, but also in their language and culture. It also alludes to its pride of place as perhaps the most decorated element of Yorùbá architecture. From private homes, to the homes of the rich, shrines, and palaces, Yorùbá doors are usually imbued with a considerable array of images and icons that proclaims the owner's identity, religion, occupation. The Yorùbá are not unique in this respect. For example, among the Dogon, the door is as important as the house on which it is affixed. The granary, according to Willett (2002: 176), protects the the food stored inside it, while the door is seen or referred to as an element not only for physical protection, but also as a spiritual means of warding off unwanted spirits. It is reasonable, therefore, to expect the door to receive aesthetic attention by embellishment with an array of images.
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  • Date Issued: 2018

Three new pentacyclic triterpenoids from twigs of Manniophyton fulvum (Euphorbiaceae)

  • Authors: Mbeunkeu, Ahri B D , Noundou, Xavier S , Krause, Rui W M , Teinkela, Jean E M , Laatsch, Hartmut , Azebaze, Anatole G B , Vardamides, Juliette C , Tala, Michel F
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/126782 , vital:35922 , https://doi.org/10.1016/j.phytol.2018.06.019
  • Description: Phytochemical investigation of the methanol extracts of the twigs of Manniophyton fulvum has led to the isolation and characterization of three new pentacyclic triterpenoids, designated as 3α,28-dihydroxyfriedelan-1-one (1), manniotaraxerol A (3) and manniotaraxerol B (4), along with fourteen known compounds, 3α-hydroxy-1-oxofriedelane (2), betulinic acid (5), friedelin (S1), taraxerol (S2), a mixture of stigmasterol (S3) and β-sitosterol (S4), herranone (S5), docosanoic acid (S6), ursolic acid (S7), nasutin B (S8), bergenin (S9), stigmasterol-3-O-β-Dglucopyranoside (S10), 1,2-di-O-palmitoyl-3-O-(6-sulfo-α-D-quinovopyranosyl)glycerol (S11), and aridanin (S12). The structures of all compounds were determined by comprehensive spectroscopic analyses (1D and 2D NMR, EI and ESI-MS). 3α,28-Dihydroxyfriedelan-1-one (1), 3α-hydroxy-1-oxofriedelane (2), manniotaraxerol A (3), manniotaraxerol B (4), and betulinic acid (5) were evaluated against HeLa (human cervix adenocarcinoma) cancer cells. Manniotaraxerol A (3) showed weak in vitro cytotoxicity with a cell viability value of 49.3%. Betulinic acid (5) also showed significant cytotoxicity against HeLa cell with a cell viability value of 4.0%; the other compounds were inactive in this test.
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  • Date Issued: 2018

Ties that bind: the ambiguous role played by social capital in black working class first-generation South African students’ negotiation of university life

  • Authors: Vincent, Louise , Hlatshwayo, M
  • Date: 2018
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/141722 , vital:37999 , DOI: 10.20853/32-3-2538
  • Description: In this article we examine the ambiguous role that social capital plays in first generation Black working class South African students’ negotiation of entry into an elite higher education institutional environment. First generation student experiences have a particular relevance in South Africa where student enrolment increased by 193 000 between 1993 and 2004, with many of the new entrants first-generation students. South African research on first-generation working class Black students has focused on the low proportion of these students who reach university at all and among those who do enter university, the significant number who perform poorly or drop out before completing their degrees. The role played by social capital (social networks, close friends, associations, clubs and other affiliations) in these students’ experiences of negotiating their entry into university has been little explored.
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  • Date Issued: 2018

Time-driven activity-based costing for small to medium manufacturing enterprises in South Africa: an integrated balanced scorecard approach

  • Authors: Reynolds, Arthur
  • Date: 2018
  • Subjects: Activity-based costing , Managerial accounting Small business -- Finance Small business -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10948/35125 , vital:33630
  • Description: The failure rate of small to medium enterprises in South Africa is very high. This is problematic as there is a large dependence on the ongoing success of small to medium enterprises from the economy and society. Increasing labour costs and inflationary pressure have contributed to the high failure rates of small to medium enterprises. In addition, the manufacturing sector for small to medium enterprises has showed a decline over recent years. There is thus a need to identify and manage the critical success factors (CSFs) for small to medium manufacturing enterprises. The balanced scorecard (BSC) has been used successfully to manage CSFs. Furthermore, research on time-driven activity-based costing (TDABC) has illustrated that this costing system could be implemented successfully at small to medium enterprises across the world to manage costs, and that the BSC could be used successfully together with TDABC. However, research has shown that implementing a BSC at small to medium enterprises could be challenging. As a result, the theory of constraints (TOC) that can be used to explain the phenomenon of constraints of resources is recognised as the underlying theory for this study. The availability of a generic yet adaptable BSC could potentially enable owners and managers of small to medium manufacturing enterprises to manage the CSFs that together with the TDABC system can lower costs and identify unused capacity. This study has developed and implemented a generic TDABC/BSC costing system by investigating literature and conducting a Delphi study and a case study at a small to medium enterprise specialising in manufacturing. Firstly, it was found that a generic BSC for small to medium manufacturing enterprises could be developed by using a Delphi study to create a BSC template with optional key metrics/key performance indicators (KPIs) to suit different types of manufacturing industries. Secondly, it was demonstrated in a case study that TDABC could still be beneficial for a small to medium manufacturing enterprise if focus is only on a single product. Thirdly, it became evident that the system could be used to manage the TOC. Finally, the case study shows that cost savings could be achieved in small to medium enterprise by using the integrated TDABC/BSC costing system and by that increase the success of the business.
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  • Date Issued: 2018

Tolerance of salt marsh ecotone species to salinity and inundation

  • Authors: Matabane, Rebotile
  • Date: 2018
  • Subjects: Geobiology , Plant ecology Plant ecophysiology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/22409 , vital:29967
  • Description: Ecophysiology studies help understand and predict the response of coastal ecosystems to changes in environmental factors and complement modelling and mapping studies that often do not take into account the physiological tolerances of the biota. Along the South African coastline predicted sea level rise will shift the tidal front and result in larger submerged areas. The frequency and magnitude of inundation and subsequent salinity stress is expected to influence the survival and distribution of salt marsh. An understanding of the effects of sea level rise on plant growth and survival is required to predict, manage and adapt to climate change. The aim of this study was to investigate the response of the salt marsh ecotone species Disphyma crassifolium (L.) L. Bol. to salinity and submergence stress and to measure in situ spatial and temporal changes in vegetation cover and its environmental drivers in the Swartkops Estuary in South Africa.Three greenhouse experiments assessed morphological and physiological responses to salinity and inundation treatments on D. crassifolium. The first experiment used three inundation levels (dry, tidal and waterlogged) and five salinity treatments (0, 8, 18, 35 and 45 ppt) and ran for six weeks. The second experiment also had three inundation levels (dry, waterlogged and completely submerged) and five salinity treatments (0, 8, 18, 35 and 45 ppt) and ran for 12 weeks. The third experiment investigated the response of a narrower range of salinity treatments under dry conditions only; namely 0, 5, 10, 15, 20, 25, 30 and 35 ppt and ran for seven weeks. Experiment 1 showed that D. crassifolium growth decreased with an increase in salinity. Optimum growth occurred at lower salinity treatments of 0 to 18 ppt under dry conditions. Plant height and leaf succulence was the highest at 0 ppt (12.4 ± 1.2 cm and 94.9 ± 0.6 % respectively). The number of leaves produced were the highest at 0 ppt (47.7 ± 8.9 number of leaves) and 8 ppt (59.6 ± 6.3 number of leaves). The root/shoot ratio for dry treatment plants was significantly lower (p < 0.005, n=12) than that of waterlogged and tidal-treated plants. This was as a result of more leaves being produced in dry treatments. In Experiment 2 D. crassifolium plants died after one month of submergence regardless of the salinity. Once again optimum growth occurred at salinity of 0 to 18 ppt under the dry treatment. Within the waterlogged treatment, 0 and 8 ppt treated plants developed adventitious roots and started flowering after two weeks.The electrolyte leakage increased with salinity, however the waterlogged plants had significantly higher electrolyte leakage compare to the dry treated plants. Within the waterlogged treatment electrolyte leakage was at the highest at 18 ppt (36.5 ± 4.2 %) and lowest at 0 ppt (26.1 ± 3.3 %). Photosynthetic pigments showed significant difference across the two inundation states. However, chlorophyll and carotenoids concentrations did not differ significantly with an increase in salinity in each treatment. D. crassifolium tolerated stress through accumulation of solutes that increased in concentration with salinity treatment. The proline concentration ranged between 23.1 to 102 mM while the glycinebetaine concentration ranged between 36.6 and 120 mM. Experiment 3 showed that growth was highest at salinity < 20 ppt. The highest growth based on plant height was measured at 0 and 10 ppt. Spatial and temporal changes in the salt marsh terrestrial boundary was investigated in situ at two sites in the Swartkops Estuary using three line transects per site extending from the terrestrial boundary to the supratidal salt marsh. Plant cover abundance was measured seasonally along with sediment moisture content, electrical conductivity, redox potential, organic content and sediment particle size. There were five sampling trips between April 2016 to July 2017, representing autumn, winter and summer. The transects at Sites 1 and 2 were divided into three zones; a Drosanthemum zone (dominated by Drosanthemum parvifolium (Haw.) Schwantes at the beginning of the transect), a Sarcocornia zone (in the middle of the transect and dominated by Sarcocornia pillanssii (Moss) A.J. Scott) and a Disphyma zone at the end of the transect in the supratidal marsh (dominated by Disphyma crassifolium). There was no significant seasonal change in vegetation cover except in Site 1 during Winter 2016 when Isolepis sp. appeared and was dominant in the middle of the transects. Sediment assessed from each of the zones showed physicochemical ranges within the typical ecotone sediment characteristics. Moisture content ranged between 0.6 and 30.9 % at Site 1 and between 3 and 33.8 % at Site 2. Electrical conductivity ranged between 0.9 and 10.2 mS cm-1 at Site 1 and between 1.4 and 17.8 mS cm-1 at Site 2. Organic content ranged between 1.9 and 16 % at Site 1 and between 3.9 and 16.3 % at Site 2. Redox potential ranged between 208 and 406.7 mV at Site 1 and between 202.7 and 389.67 mV at Site 2. Sediment particle size consisted of sand (>70%), silt (>15%) and clay (<10%). The aim of this study was to provide insight on the effects of salinity and inundation on the morphology and physiology of D. crassifolium occurring in the salt marsh terrestrial boundary and to assess its spatial and temporal changes over time. The research suggests that D. crassifolium is more sensitive to inundation than salinity. Furthermore the succulent was found in the field to be dominant in conditions which the glasshouse experiments showed to be its optimum growth. That is, in dry sediments with salinity of < 18 ppt. Therefore, if these conditions change (sediment moisture and salinity), the cover abundance of D. crassifolium could significantly change in the field.
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  • Date Issued: 2018

Tomographic imaging of East African equatorial ionosphere and study of equatorial plasma bubbles

  • Authors: Giday, Nigussie Mezgebe
  • Date: 2018
  • Subjects: Ionosphere -- Africa, Central , Tomography -- Africa, Central , Global Positioning System , Neural networks (Computer science) , Space environment , Multi-Instrument Data Analysis System (MIDAS) , Equatorial plasma bubbles
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/63980 , vital:28516
  • Description: In spite of the fact that the African ionospheric equatorial region has the largest ground footprint along the geomagnetic equator, it has not been well studied due to the absence of adequate ground-based instruments. This thesis presents research on both tomographic imaging of the African equatorial ionosphere and the study of the ionospheric irregularities/equatorial plasma bubbles (EPBs) under varying geomagnetic conditions. The Multi-Instrument Data Analysis System (MIDAS), an inversion algorithm, was investigated for its validity and ability as a tool to reconstruct multi-scaled ionospheric structures for different geomagnetic conditions. This was done for the narrow East African longitude sector with data from the available ground Global Positioning Sys-tem (GPS) receivers. The MIDAS results were compared to the results of two models, namely the IRI and GIM. MIDAS results compared more favourably with the observation vertical total electron content (VTEC), with a computed maximum correlation coefficient (r) of 0.99 and minimum root-mean-square error (RMSE) of 2.91 TECU, than did the results of the IRI-2012 and GIM models with maximum r of 0.93 and 0.99, and minimum RMSE of 13.03 TECU and 6.52 TECU, respectively, over all the test stations and validation days. The ability of MIDAS to reconstruct storm-time TEC was also compared with the results produced by the use of a Artificial Neural Net-work (ANN) for the African low- and mid-latitude regions. In terms of latitude, on average,MIDAS performed 13.44 % better than ANN in the African mid-latitudes, while MIDAS under performed in low-latitudes. This thesis also reports on the effects of moderate geomagnetic conditions on the evolution of EPBs and/or ionospheric irregularities during their season of occurrence using data from (or measurements by) space- and ground-based instruments for the east African equatorial sector. The study showed that the strength of daytime equatorial electrojet (EEJ), the steepness of the TEC peak-to-trough gradient and/or the meridional/transequatorial thermospheric winds sometimes have collective/interwoven effects, while at other times one mechanism dominates. In summary, this research offered tomographic results that outperform the results of the commonly used (“standard”) global models (i.e. IRI and GIM) for a longitude sector of importance to space weather, which has not been adequately studied due to a lack of sufficient instrumentation.
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  • Date Issued: 2018

Topic : an appraisal of youth social entrepreneurship for positive youth development in Amathole District Municipality, Eastern Cape

  • Authors: Ntlemeza, Aphiwe Ziyanda
  • Date: 2018
  • Subjects: Social entrepreneurship -- South Africa -- Eastern Cape Youth development -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , Rural Development
  • Identifier: http://hdl.handle.net/10353/10974 , vital:35971
  • Description: This study explores social entrepreneurship projects which are specifically run by the youth in an attempt to mitigate poverty and unemployment in the Amathole District Municipality, Eastern Cape. It also evaluates the extent to which selected social entrepreneurship interventions have contributed to employment creation and income generation. Furthermore, not only does the study investigate social entrepreneurship opportunities available for rural youth in Amathole but goes further to evaluate the sustainability of existing social entrepreneurship projects. The challenges faced by rural youth in pursuing social entrepreneurship are also explored. In so doing, the study is underpinned by the Positivist Youth Development (PYD) theory. The study found that the youth of Amathole District Municipality have a positive attitude towards social entrepreneurship. They engage in a variety of social enterprises. However, the youth face many constraints such as lack of access to finance, lack of business skills, lack of entrepreneurial education and lack of technical support. All these constraints are interrelated and lead to issues of unsustainability and limited income generation and employment creation. Informed by these constraints, the study recommends coordinated awareness campaigns and government (national/provincial) response about social entrepreneurship and community needs within Amathole. To further understand social entrepreneurship, there is need for further studies to investigate the attitudes and constraints of women towards social entrepreneurship as well as youth’s understanding of social entrepreneurship in general.
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  • Date Issued: 2018

Topic map for representing network security competencies

  • Authors: Yekela, Odwa
  • Date: 2018
  • Subjects: Computer networks , Computer networks -- Security measures Computers -- Access control
  • Language: English
  • Type: Thesis , Masters , MIT
  • Identifier: http://hdl.handle.net/10948/36368 , vital:33931
  • Description: Competencies represent the knowledge, skills and attitudes required for job roles. Organisations need to understand and grow competencies within their workforce in order to be more competitive and to maximise new market opportunities. Competency Management is the process of introducing, managing and enforcing competencies in organisations. Through this process, occupational competencies can be assessed to see if candidates match the required job role expectations. The assessment of competencies can be conceptualised from two perspectives. The rst is `competency frameworks', which describe competencies from a high-level overview. As such, they are regarded as theWhat" element of competency. The second perspective is `competencybased learning', which focuses on addressing competencies from a more detailed, task-oriented perspective. Competency-based learning is regarded as the How" element of competency. Currently, there is no available tool that can map the What" with the How" element of competency. Such a mapping would provide a more holistic approach to representing competencies. This dissertation adopts the topic map standard in order to demonstrate a holistic approach to mapping competencies, specially in network security. This is accomplished through the design and evaluation of a Design Science artefact. In this research process a topic map data model was constructed from mapping the `What' and `How' elements together. To demonstrate the applicability of the model, it was implemented in a Computer Security Incident Response Team (CSIRT) recruitment scenario. The aim of this demonstration was to prove that the topic map could be implemented in an organisational context.
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  • Date Issued: 2018

Toward distributed key management for offline authentication

  • Authors: Linklater, Gregory , Smith, Christian , Herbert, Alan , Irwin, Barry V W
  • Date: 2018
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/430283 , vital:72680 , https://doi.org/10.1145/3278681.3278683
  • Description: Self-sovereign identity promises prospective users greater control, security, privacy, portability and overall greater convenience; however the immaturity of current distributed key management solutions results in general disregard of security advisories in favour of convenience and accessibility. This research proposes the use of intermediate certificates as a distributed key management solution. Intermediate certificates will be shown to allow multiple keys to authenticate to a single self-sovereign identity. Keys may be freely added to an identity without requiring a distributed ledger, any other third-party service or sharing private keys between devices. This research will also show that key rotation is a superior alternative to existing key recovery and escrow systems in helping users recover when their keys are lost or compromised. These features will allow remote credentials to be used to issuer, present and appraise remote attestations, without relying on a constant Internet connection.
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  • Date Issued: 2018

Towards a collection of cost-effective technologies in support of the NIST cybersecurity framework

  • Authors: Shackleton, Bruce Michael Stuart
  • Date: 2018
  • Subjects: National Institute of Standards and Technology (U.S.) , Computer security , Computer networks Security measures , Small business Information technology Cost effectiveness , Open source software
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/62494 , vital:28199
  • Description: The NIST Cybersecurity Framework (CSF) is a specific risk and cybersecurity framework. It provides guidance on controls that can be implemented to help improve an organisation’s cybersecurity risk posture. The CSF Functions consist of Identify, Protect, Detect, Respond, and Recover. Like most Information Technology (IT) frameworks, there are elements of people, processes, and technology. The same elements are required to successfully implement the NIST CSF. This research specifically focuses on the technology element. While there are many commercial technologies available for a small to medium sized business, the costs can be prohibitively expensive. Therefore, this research investigates cost-effective technologies and assesses their alignment to the NIST CSF. The assessment was made against the NIST CSF subcategories. Each subcategory was analysed to identify where a technology would likely be required. The framework provides a list of Informative References. These Informative References were used to create high- level technology categories, as well as identify the technical controls against which the technologies were measured. The technologies tested were either open source or proprietary. All open source technologies tested were free to use, or have a free community edition. Proprietary technologies would be free to use, or considered generally available to most organisations, such as components contained within Microsoft platforms. The results from the experimentation demonstrated that there are multiple cost-effective technologies that can support the NIST CSF. Once all technologies were tested, the NIST CSF was extended. Two new columns were added, namely high-level technology category, and tested technology. The columns were populated with output from the research. This extended framework begins an initial collection of cost-effective technologies in support of the NIST CSF.
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  • Date Issued: 2018

Towards a community based conservation strategy for wetlands in Uganda

  • Authors: Barakagira, Alex
  • Date: 2018
  • Subjects: Conservation of natural resources , Wetland conservation -- Uganda Wetlands -- Uganda -- Management
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10948/23902 , vital:30640
  • Description: Conservation of natural resources in Uganda focuses primarily on protected areas, including savannah national parks, mainly for conserving big game and forests, for controlling the harvest of commercially valuable timber resources, with less concern for wetlands. Later, policies and legislation in Uganda favoured agricultural production rather than the conservation of wetlands, a situation that culminated in their degradation. In a bid to counter the effects of wetlands degradation, Wetland Management Agencies were created. These agencies excluded the input of members of the local communities who reside in the wetlands environs. Local communities were not consulted on matters concerning management and conservation strategies, a situation that may have escalated the problem of wetlands degradation. Local knowledge is needed for the effective management and conservation of the wetlands and it is essential that local communities are included in decision making. This research study is more of an initiative for providing information that may be essential for the formulation of a community based conservation strategy for wetlands in Uganda. The study aimed to identify and characterize activities carried out by members of the local communities in wetlands found in central and western Uganda that are responsible for their progressive degradation; to assess the performance of existing Wetlands Management Institutions towards protection and conservation of wetlands in Uganda; to ascertain whether the acts and policies that have been promulgated for the protection of wetlands in Uganda have been adhered to by members of the local communities and to evaluate three community based conservation case studies with two vastly different outcomes in order to come up with the community-based conservation principles Ugandan communities may need to adopt to achieve sustainable utilisation and conservation of wetland resources. To achieve the objectives stated above, the researcher used a multi-disciplinary methodology that required several areas of expertise and sources of information. Hence, to accomplish the study, primary sources of data that included quantitative and qualitative data were collected from the study participants by means of a questionnaire survey, key informant interviews and direct observations. Secondary sources of data centred on published Ugandan acts and policies; textbooks; case study articles and journal articles. The study revealed a host of activities in which members of the local community are involved that have led to the degradation of the wetlands in Uganda. These include but are not limited to crop cultivation, dairy farming and unsustainable wetland resource harvesting. A number of other reasons for the degradation of the wetlands include unclear ownership of the wetlands, unclear wetland boundaries and a lack of awareness of the indirect benefits wetlands provide for members of the local communities. The study disclosed that wetlands management institutions have not been effective in the protection and conservation of wetlands in Uganda, mainly due to political interference and inadequate funding for the institutions’ conservation activities. The acts and policies that were promulgated for the protection and conservation of wetlands have been selectively implemented in some places and in others completely ignored, culminating in the degradation of the wetlands. The study revealed that effective community based conservation of wetlands in Uganda includes: initiation of the planning, implementation, monitoring and evaluation of all wetlands activities being borne by members of the local community; government introducing alternative income-generating activities aimed to reduce over-reliance on wetland resources and education of the local communities regarding the community-based projects’ objectives in order to garner their support. Recommendations emanating from this study are that the Land Act should be amended to specify a particular land tenure system, preferably freehold, which may promote the conservation of wetlands in Uganda; fertilizers (organic) should be introduced in the study area to fertilize the uplands that have reportedly become infertile in order to reduce the pressure the local community members are exerting on the wetlands for agriculture; wetlands management institutions should be empowered financially and political interference in activities aimed at conservation of wetlands in Uganda must cease. There should be uniform implementation of the rules and regulations stipulated in the acts and policies for all members of the public concerning wetlands protection. Lastly, essential community based conservation principles, as stated above, need to be applied carefully and adhered to if effective implementation of community-based conservation of wetlands is to be achieved in Uganda.
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  • Date Issued: 2018

Towards a framework to enhance entry-level national diploma students' learning of computer programming - effects of guided inquiry learning

  • Authors: Lukose, Jose
  • Date: 2018
  • Subjects: Computer programming -- Study and teaching Computer science -- Study and teaching (Higher)
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/9522 , vital:34362
  • Description: Research reports using global data show that the failure rates in introductory programming courses average about 32 percent. This study assessed the effect of elements of Guided Inquiry Learning (GIL) on enhancing academic performance of first year students in Introduction to Computer Programming course. As learners from schools join the university and enrol for different courses, they find the sudden transformation quite challenging. This makes it more challenging for first year university students, especially in difficult courses such as Introduction to Programming. As times change with advances in technology, the traditional ways of presenting information during teaching–learning interface may not address students’ needs. Lecturers and university stakeholders make efforts to address these challenges by proposing innovative teaching ways. One of the common approaches that have been used profitably in other science and engineering programmes is GIL. It is a form of inductive collaborative learning approach where students are presented with a challenge which challenges them to accomplish the desired learning outcomes in the process of responding to the posed challenge. The strategies in GIL include, among others, learning teams who participate in intra- and inter-learner interactions besides lecturer-learner interactions, linking theory and practical information cementing skills and problem solving strategies, scaffolding information, blended learning by integrating both traditional and technology-assisted learning, inquiry activities such as initiating investigations, gathering data, and critiquing evidence to come up with evidence-based solutions. The objective was to apply GIL to this module and observe if there were gains in students’ academic performance. This study was located in the pragmatic paradigm using action research design and a mixed method approach. The sample consisted offirst year students enrolled for Introduction to programming which was a year-long course (two semesters) at a South African university. The population consisted of the only 49 students who were registered for the module under focus. A group of 20 students were considered for the whole year in the GIL experiment. Although it would students were considered for the whole year in the GIL experiment. Although it would students were considered for the whole year in the GIL experiment. Although it would have been ideal to have experimental and control groups with same number of students, that was not possible in this study, because only 20 out of the 49 who were willing to be included in the experimental group. The present researcher employed willing to be included in the experimental group. The present researcher employed three of these GIL strategies in teaching the module Introduction to Programming to the experimental group while another colleague continued with traditional teaching in the control group. Care was taken to limit the insider outsider conflict. Both groups were assessed by the same assessment tools at the same times. Results from these assessments together with focus group interviews provided the core data for this study. Both quantitative and qualitative analyses were carried out on the data, statistical analysis (mainly, chi-Square and t-test) for the former and thematic analysis for the latter. Results indicated gains in the experimental group such as enhanced motivation, interaction, intra-group social cohesion, creativity and provided students the confidence to share knowledge and skills with their peers and keep everyone focused on the course contents. These gains are reflected in higher year marks and pass rates than those in the control group as the analysed data indicate. A study that will pilot the GIL framework in several universities with different teaching modes and large classes are recommended.
  • Full Text:
  • Date Issued: 2018
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