Classification and clustering based methods for outlier detection of solar resource data
- Authors: Abrahams, Waldo
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55423 , vital:51996
- Description: Almost 90% of the primary global energy demand is serviced from the burning of fossil fuels (Abas, Kalair & Khan, 2015). Owing to the detrimental environmental impact of this, a global energy transition to the use of renewable energy, including solar energy, is needed (Gielen et al., 2019). An important aspect that inhibits the growth of solar energy is accurate solar resource data. Such data is needed because knowledge of the future reliability and quality of energy production is required to analyse a system’s performance and determine financial implications (Sengupta et al., 2017). Existing methods used to detect outliers in solar resource data do not efficiently identify outliers and an accurate and robust approach is required (Eastwood, 2019). Using simulated and real-world data, this study investigates the use of several classification methods, along with a two-stage clustering-classification approach to accurately identify outliers in solar resource data. The Treebag method proves to be an adequate outlier detection method for solar resource data. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Abrahams, Waldo
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55423 , vital:51996
- Description: Almost 90% of the primary global energy demand is serviced from the burning of fossil fuels (Abas, Kalair & Khan, 2015). Owing to the detrimental environmental impact of this, a global energy transition to the use of renewable energy, including solar energy, is needed (Gielen et al., 2019). An important aspect that inhibits the growth of solar energy is accurate solar resource data. Such data is needed because knowledge of the future reliability and quality of energy production is required to analyse a system’s performance and determine financial implications (Sengupta et al., 2017). Existing methods used to detect outliers in solar resource data do not efficiently identify outliers and an accurate and robust approach is required (Eastwood, 2019). Using simulated and real-world data, this study investigates the use of several classification methods, along with a two-stage clustering-classification approach to accurately identify outliers in solar resource data. The Treebag method proves to be an adequate outlier detection method for solar resource data. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2022
- Full Text:
- Date Issued: 2022-04
Hydraulic vulnerability of Subtropical Thicket to drought : a remote sensing and physiological perspective
- Authors: Buttner, Daniel Harry
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55455 , vital:52017
- Description: Water availability is one of largest constraints on plant survival, growth, and species distribution globally. The recent escalation in tree mortality coupled with declining precipitation and amplified temperatures has implicated drought as a major cause behind many large-scale dieback events observed across the world. Raising the question, what makes some species more resistant and persist while others dwindle and vanish from the landscape? The observed variability in species drought susceptibility demonstrates the complexity of physiological responses of plants to changes in water availability. Hydraulic dysfunction in plants has been purported to be the key mechanism behind drought-induced mortality provoking interest in hydraulic traits and critical thresholds of xylem physiological function. The capability of species to maintain hydraulic functionality under drought strongly influences the survival and general productivity towards water deficits. Hence, two core objectives, and subsequently aims, of this thesis are firstly to investigate the effect of drought on Subtropical Thicket vegetation health and productivity, and secondly to examine the underpinning physiological mechanisms and functional thresholds relaying speciesspecific drought vulnerability within this semi-arid biome. In first data chapter, this thesis offers an assessment of vegetation change under drought and its influence on plant physiological function and productivity across a subsection of Subtropical Thicket distribution. Additionally, this chapter provides a regional scale perspective of drought on Subtropical Thicket flora in the Eastern Cape of South Africa. A severe anomalous dieback event, which coincided with extreme, accumulative drought conditions was observed in 2020. Employing a combination of field-based approaches and remote sensing, this chapter aimed to provide a comprehensive report of the extent and severity of crown defoliation and canopy dieback following this event, additionally describing predisposing and compounding factors. Based on Standardized Precipitation Evapotranspiration and Standardized Precipitation Indices this event began in 2015 and coincided with amplified temperatures, exacerbating evaporative demand. Aerial UAV surveys and field-based investigations were undertaken. Remotely sensed (RS) indices provided an avenue for extensive spatiotemporal investigations to uncover the extent of drought-related impact on vegetation productivity and discuss potential underpinning mechanisms behind drought-induced mortality in Subtropical Thicket. Leveraging long-term time series RS data, Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI), from Moderate Resolution Imaging Spectroradiometer (MODIS) satellites as a proxy vegetation physiological status in combination with SPI and SPEI describing drought condition and groundbased surveying defining canopy vitality condition this study incidentally addressed the aim of endeavoring to link drought-induced mortality and early warning symptoms observed in the field with RS time series data to describe drought impacts across Subtropical Thicket. Furthermore, the findings of this chapter demonstrate the spatial and temporal heterogeneity in drought impacts on Subtropical Thicket. The recent drought of 2015 till 2021 is the longest documented period for the past 50 years in which there has been no accumulated net positive water availability, this apparently perpetual state of water deficiency has enacted a high cost for vegetation productivity and growth for the study area, exhibited well by average NDVI values of less than -0.5 for over 70% of the research site. The findings of this chapter report, to the contrary of anecdotal suggestions in the literature, on the intrinsic tolerance of Subtropical Thicket and that ii drought has a far more significant role on overall vegetation productivity, growth, and mortality in this region. The second data chapter assess whole-plant physiological functionality during a drought event in the Eastern Cape, South Africa. This is the first study in Subtropical Thicket to quantify in situ hydraulic functional integrity under a natural drought event testing the leading hypothesis describing tree mortality – hydraulic dysfunction. This chapter firstly, investigates hydraulic traits (e.g., turgor loss point) and describe key physiological thresholds (e.g., P50) for maintaining function during drought. Secondly, levels of native embolism were determined under drought conditions and combined with measurements of xylem vulnerability to embolism providing an estimation of degree of hydraulic dysfunction experienced by six dominant woody canopy species in Subtropical Thicket – to quantify interspecific drought tolerance and susceptibility. Subtropical Thicket species exhibited remarkable tolerance towards desiccation (TLP from as low as -3MPa) and hydraulic functional resistance to embolism (P50 value as low as -7.89MPa). The observed unexpected drought resilience of subtropical derived lineages highlights the intrinsic evolutionary role aridification had, selecting for greater embolism resistance and community-level conservatism in drought resistance of Subtropical Thicket. The level of native embolism and hydraulic safety margins identified two species (Schotia latifolia and Polyagla myrtifolia) that were the most vulnerable, and a third (Pappea capensis) moderately vulnerable, then the remaining studied species – this could result in community-level adjustments in species composition and structure under future projected climate change scenarios where, increased frequencies of drought events are anticipated. This retrospective assessment of canopy vigor with physiological functional thresholds evokes hydraulic dysfunction as the principal mechanism of observed Subtropical Thicket dieback to drought. This chapter provides crucial in situ data for predictive assertions around drought-induced mortality risk in a phylogenetically diverse and climatically unique biome of southern Africa; and is the first to identify critical hydraulic thresholds for tree species within this region. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Buttner, Daniel Harry
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55455 , vital:52017
- Description: Water availability is one of largest constraints on plant survival, growth, and species distribution globally. The recent escalation in tree mortality coupled with declining precipitation and amplified temperatures has implicated drought as a major cause behind many large-scale dieback events observed across the world. Raising the question, what makes some species more resistant and persist while others dwindle and vanish from the landscape? The observed variability in species drought susceptibility demonstrates the complexity of physiological responses of plants to changes in water availability. Hydraulic dysfunction in plants has been purported to be the key mechanism behind drought-induced mortality provoking interest in hydraulic traits and critical thresholds of xylem physiological function. The capability of species to maintain hydraulic functionality under drought strongly influences the survival and general productivity towards water deficits. Hence, two core objectives, and subsequently aims, of this thesis are firstly to investigate the effect of drought on Subtropical Thicket vegetation health and productivity, and secondly to examine the underpinning physiological mechanisms and functional thresholds relaying speciesspecific drought vulnerability within this semi-arid biome. In first data chapter, this thesis offers an assessment of vegetation change under drought and its influence on plant physiological function and productivity across a subsection of Subtropical Thicket distribution. Additionally, this chapter provides a regional scale perspective of drought on Subtropical Thicket flora in the Eastern Cape of South Africa. A severe anomalous dieback event, which coincided with extreme, accumulative drought conditions was observed in 2020. Employing a combination of field-based approaches and remote sensing, this chapter aimed to provide a comprehensive report of the extent and severity of crown defoliation and canopy dieback following this event, additionally describing predisposing and compounding factors. Based on Standardized Precipitation Evapotranspiration and Standardized Precipitation Indices this event began in 2015 and coincided with amplified temperatures, exacerbating evaporative demand. Aerial UAV surveys and field-based investigations were undertaken. Remotely sensed (RS) indices provided an avenue for extensive spatiotemporal investigations to uncover the extent of drought-related impact on vegetation productivity and discuss potential underpinning mechanisms behind drought-induced mortality in Subtropical Thicket. Leveraging long-term time series RS data, Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI), from Moderate Resolution Imaging Spectroradiometer (MODIS) satellites as a proxy vegetation physiological status in combination with SPI and SPEI describing drought condition and groundbased surveying defining canopy vitality condition this study incidentally addressed the aim of endeavoring to link drought-induced mortality and early warning symptoms observed in the field with RS time series data to describe drought impacts across Subtropical Thicket. Furthermore, the findings of this chapter demonstrate the spatial and temporal heterogeneity in drought impacts on Subtropical Thicket. The recent drought of 2015 till 2021 is the longest documented period for the past 50 years in which there has been no accumulated net positive water availability, this apparently perpetual state of water deficiency has enacted a high cost for vegetation productivity and growth for the study area, exhibited well by average NDVI values of less than -0.5 for over 70% of the research site. The findings of this chapter report, to the contrary of anecdotal suggestions in the literature, on the intrinsic tolerance of Subtropical Thicket and that ii drought has a far more significant role on overall vegetation productivity, growth, and mortality in this region. The second data chapter assess whole-plant physiological functionality during a drought event in the Eastern Cape, South Africa. This is the first study in Subtropical Thicket to quantify in situ hydraulic functional integrity under a natural drought event testing the leading hypothesis describing tree mortality – hydraulic dysfunction. This chapter firstly, investigates hydraulic traits (e.g., turgor loss point) and describe key physiological thresholds (e.g., P50) for maintaining function during drought. Secondly, levels of native embolism were determined under drought conditions and combined with measurements of xylem vulnerability to embolism providing an estimation of degree of hydraulic dysfunction experienced by six dominant woody canopy species in Subtropical Thicket – to quantify interspecific drought tolerance and susceptibility. Subtropical Thicket species exhibited remarkable tolerance towards desiccation (TLP from as low as -3MPa) and hydraulic functional resistance to embolism (P50 value as low as -7.89MPa). The observed unexpected drought resilience of subtropical derived lineages highlights the intrinsic evolutionary role aridification had, selecting for greater embolism resistance and community-level conservatism in drought resistance of Subtropical Thicket. The level of native embolism and hydraulic safety margins identified two species (Schotia latifolia and Polyagla myrtifolia) that were the most vulnerable, and a third (Pappea capensis) moderately vulnerable, then the remaining studied species – this could result in community-level adjustments in species composition and structure under future projected climate change scenarios where, increased frequencies of drought events are anticipated. This retrospective assessment of canopy vigor with physiological functional thresholds evokes hydraulic dysfunction as the principal mechanism of observed Subtropical Thicket dieback to drought. This chapter provides crucial in situ data for predictive assertions around drought-induced mortality risk in a phylogenetically diverse and climatically unique biome of southern Africa; and is the first to identify critical hydraulic thresholds for tree species within this region. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2022-04
The aesthetics of hegemony: a speculative design proposal exploring the convergence of surveillance capitalism and brain-computer interface technologies in the future
- Authors: Davies, James Tibbott
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54417 , vital:46517
- Description: This study examines the power dynamics of surveillance capitalism, and its role in shaping cultural hegemony. The research was expressed using graphic design to illustrate a (potential) future where Brain-Computer Interfaces (BCIs) and surveillance capitalism converge. The critique focused on Google and Facebook’s hegemony in the data-surveillance marketplace and what role this has in shaping global discourse. Both companies are funding the development of BCIs, with the aim of using brain signals as a means of interacting with the digital world, which would give the two biggest advertising companies in the world access to new sources of data. A speculative design framework was utilized to visually question the societal implications of this emerging technology and the funding behind its development. A theoretical investigation of the concepts underpinning critical theory and critical design was conducted to help clarify and critically inform this methodological approach, promoting the use of practice-based design as a critically reflective investigative tool. The resulting artefacts designed using this process were showcased in the form of a website and video that act as a visual embodiment the research, demonstrating the efficacy of this approach and the value of using communication design as a mechanism to question the status quo. , Thesis (MA) -- Faculty of Humanities, School of Visual and Performing Arts, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Davies, James Tibbott
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54417 , vital:46517
- Description: This study examines the power dynamics of surveillance capitalism, and its role in shaping cultural hegemony. The research was expressed using graphic design to illustrate a (potential) future where Brain-Computer Interfaces (BCIs) and surveillance capitalism converge. The critique focused on Google and Facebook’s hegemony in the data-surveillance marketplace and what role this has in shaping global discourse. Both companies are funding the development of BCIs, with the aim of using brain signals as a means of interacting with the digital world, which would give the two biggest advertising companies in the world access to new sources of data. A speculative design framework was utilized to visually question the societal implications of this emerging technology and the funding behind its development. A theoretical investigation of the concepts underpinning critical theory and critical design was conducted to help clarify and critically inform this methodological approach, promoting the use of practice-based design as a critically reflective investigative tool. The resulting artefacts designed using this process were showcased in the form of a website and video that act as a visual embodiment the research, demonstrating the efficacy of this approach and the value of using communication design as a mechanism to question the status quo. , Thesis (MA) -- Faculty of Humanities, School of Visual and Performing Arts, 2021
- Full Text:
- Date Issued: 2021-12
Coordination polymers for denitrogenation of fuel oils
- Authors: Dembaremba, Tendai O
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/53630 , vital:45682
- Description: In this thesis, we present adsorptive removal of nitrogen-containing compounds from fuel oil as an alternative to complement conventional hydrotreatment to obtain ultra-low sulfur and nitrogen levels. This is in cognizance of the challenges nitrogen-containing compounds pose to the hydrotreatment process, particularly their inhibition and/or poisoning of the catalysts used in the process, of which basic nitrogen-containing compounds are the major culprits. Selectivity is the biggest challenge for adsorptive removal of nitrogen-containing compounds. We explore reticular synthesis of metal organic frameworks and the use of coordinatively unsaturated metal sites in 1-dimensional coordination polymers to achieve good selectivity for nitrogen-containing compounds. In the first part of the thesis, reticular synthesis of metal organic frameworks to control the size of the cavity, and strategically use the linkers and metal centres was envisaged. In this work we explored variation of the metal centres in the secondary building units (SBUs of the MOFs as the first step to the testing and implementation of the design strategies. Carbazole, representing carbazoles which the major compounds that remain in hydrotreated fuel, was the target compound. Four MOFs of zinc (Zn-CDC-bpe), copper (Cu-CDC-bpe), nickel (Ni-CDC-bpe) and cobalt (Co-CDC-bpe) based on the formation of a dinuclear metal paddlewheel SBUs with the ligand 9H-Carbazole-3,6-dicarboxylic acid (H2CDC) and occupation of the axial positions of the paddlewheel by 1,2-Bis(4-pyridyl)ethane (bpe) to form porous networks were synthesized. A fifth MOF containing only CDC which forms a [Zn4O(O2C-R)5(O2HC-R)] SBU was also synthesized (Zn-CDC). The ligand H2CDC was inspired by the possibility of improving selectivity for carbazole via π–π interactions through the more preferred parallel-offset stacking as well as the possibility for further substitution of the carbazole N-H to add groups that improve selectivity. The sizes of the MOF cavities can then be controlled by choosing different lengths of ligands analogous to 1,2-Bis(4-pyridyl)ethane (bpe), e.g. 4,4’-bipyridine and pyrazine. All the MOFs showed good selectivity of carbazole. The Zn-CDC MOF also had good selectivity for the basic nitrogen-containing compounds tested: quinoline, isoquinoline, quinaldine and 1-naphthylamine. Its uptake of carbazole was also slightly higher. This was attributed to the presence of an unsaturated Zn site in the SBU. Adsorption in all the MOFs was primarily due to physisorption. It was concluded that the role of the metal centre does not play a significant role in the adsorption of carbazole besides providing a template for reticular synthesis. , Thesis (PhD) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Dembaremba, Tendai O
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/53630 , vital:45682
- Description: In this thesis, we present adsorptive removal of nitrogen-containing compounds from fuel oil as an alternative to complement conventional hydrotreatment to obtain ultra-low sulfur and nitrogen levels. This is in cognizance of the challenges nitrogen-containing compounds pose to the hydrotreatment process, particularly their inhibition and/or poisoning of the catalysts used in the process, of which basic nitrogen-containing compounds are the major culprits. Selectivity is the biggest challenge for adsorptive removal of nitrogen-containing compounds. We explore reticular synthesis of metal organic frameworks and the use of coordinatively unsaturated metal sites in 1-dimensional coordination polymers to achieve good selectivity for nitrogen-containing compounds. In the first part of the thesis, reticular synthesis of metal organic frameworks to control the size of the cavity, and strategically use the linkers and metal centres was envisaged. In this work we explored variation of the metal centres in the secondary building units (SBUs of the MOFs as the first step to the testing and implementation of the design strategies. Carbazole, representing carbazoles which the major compounds that remain in hydrotreated fuel, was the target compound. Four MOFs of zinc (Zn-CDC-bpe), copper (Cu-CDC-bpe), nickel (Ni-CDC-bpe) and cobalt (Co-CDC-bpe) based on the formation of a dinuclear metal paddlewheel SBUs with the ligand 9H-Carbazole-3,6-dicarboxylic acid (H2CDC) and occupation of the axial positions of the paddlewheel by 1,2-Bis(4-pyridyl)ethane (bpe) to form porous networks were synthesized. A fifth MOF containing only CDC which forms a [Zn4O(O2C-R)5(O2HC-R)] SBU was also synthesized (Zn-CDC). The ligand H2CDC was inspired by the possibility of improving selectivity for carbazole via π–π interactions through the more preferred parallel-offset stacking as well as the possibility for further substitution of the carbazole N-H to add groups that improve selectivity. The sizes of the MOF cavities can then be controlled by choosing different lengths of ligands analogous to 1,2-Bis(4-pyridyl)ethane (bpe), e.g. 4,4’-bipyridine and pyrazine. All the MOFs showed good selectivity of carbazole. The Zn-CDC MOF also had good selectivity for the basic nitrogen-containing compounds tested: quinoline, isoquinoline, quinaldine and 1-naphthylamine. Its uptake of carbazole was also slightly higher. This was attributed to the presence of an unsaturated Zn site in the SBU. Adsorption in all the MOFs was primarily due to physisorption. It was concluded that the role of the metal centre does not play a significant role in the adsorption of carbazole besides providing a template for reticular synthesis. , Thesis (PhD) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text: false
- Date Issued: 2021-12
Perceptions of small-scale vegetable farmers on drought mitigation strategies in the Amathole District Municipality of the Eastern Cape Province
- Authors: Dingiswayo, Xolisile
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53676 , vital:45686
- Description: The present study aimed to investigate perceptions of small-scale vegetable farmers on drought mitigation strategies in the Amathole District Municipality of the Eastern Cape Province. The research objective was to investigate what small-scale vegetable farmers’ perceptions and readiness are in terms of strategies to cope with drought conditions. The study was conducted within the Mbashe, Mnquma, Amahlathi and Great Kei local municipalities of the Eastern Cape. Primary data collection was conducted among 44 small-scale vegetable farmers of the Amathole municipal district. These are farmers who receive social support from the government, are registered with the Department of Rural Development and Agrarian Reform and contribute to the fight against food insecurity in the Amathole district. The primary data was also collected from 13 agricultural extension officers with high experience in advising small-scale farmers residing in the Amathole district. Data collection took place in various local municipalities under Amathole District Municipality, namely: Mbashe, Mnquma, Amahlathi and Great Kei. A multi-method approach was adopted in this study as an appropriate technique to create an improved quality of research which eliminates the deep-rooted bias to either qualitative or quantitative methods alone. A self-administered questionnaires with both closed and open-ended questions – one for the small-scale farmer survey and the second for the extension officer survey – was employed as data collection instrument. The demographic characteristics of small-scale vegetable farmers in the survey area indicated that the present majority of farmers are married male Xhosa farmers between the ages of 56 and 65 years old, with a secondary level of education. The majority of the farmers are typically resource-poor − which implies that the added menace of drought poses the risk that small-scale vegetable farming could decline to mere subsistence level or worse. Drought was found to be a major problem in Mbashe, Mnquma, Amahlathi and Great Kei local municipalities within the Amathole municipal district, with an acute impact on farmers’ production and generation of income. From the data, it emerged that farmers are not sufficiently informed about and do not receive specific training in drought mitigation strategies. Farmers rely on drought alleviation methods but there is a lack of adaptive strategies and timely, long-term ii state intervention. Being resource-poor, these small-scale producers are reliant on natural resources – notably water for irrigating crops. The study established further that there is neither the resources nor sufficient training by and involvement of the extension service. Farmers therefore rely on the use of drought coping mechanisms and drought mitigation techniques and on adapting their production systems. The information-sharing sessions recommended can assist in improving rural livelihoods and the productivity of small-scale vegetable farmers. The absence of engagement of youth in farming means that modern conservation and innovative farming techniques and systems are not implemented towards reducing the impacts of climate change − as well as revitalizing rural areas such Amathole. Access to education about drought, improved drought coping mechanisms and adaptive strategies should be created to facilitate an exchange of traditional and modern agricultural information. The development of infrastructure in rural communities and farming areas is another factor crucial to improving farming systems and operations in the Amathole municipal district. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Dingiswayo, Xolisile
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53676 , vital:45686
- Description: The present study aimed to investigate perceptions of small-scale vegetable farmers on drought mitigation strategies in the Amathole District Municipality of the Eastern Cape Province. The research objective was to investigate what small-scale vegetable farmers’ perceptions and readiness are in terms of strategies to cope with drought conditions. The study was conducted within the Mbashe, Mnquma, Amahlathi and Great Kei local municipalities of the Eastern Cape. Primary data collection was conducted among 44 small-scale vegetable farmers of the Amathole municipal district. These are farmers who receive social support from the government, are registered with the Department of Rural Development and Agrarian Reform and contribute to the fight against food insecurity in the Amathole district. The primary data was also collected from 13 agricultural extension officers with high experience in advising small-scale farmers residing in the Amathole district. Data collection took place in various local municipalities under Amathole District Municipality, namely: Mbashe, Mnquma, Amahlathi and Great Kei. A multi-method approach was adopted in this study as an appropriate technique to create an improved quality of research which eliminates the deep-rooted bias to either qualitative or quantitative methods alone. A self-administered questionnaires with both closed and open-ended questions – one for the small-scale farmer survey and the second for the extension officer survey – was employed as data collection instrument. The demographic characteristics of small-scale vegetable farmers in the survey area indicated that the present majority of farmers are married male Xhosa farmers between the ages of 56 and 65 years old, with a secondary level of education. The majority of the farmers are typically resource-poor − which implies that the added menace of drought poses the risk that small-scale vegetable farming could decline to mere subsistence level or worse. Drought was found to be a major problem in Mbashe, Mnquma, Amahlathi and Great Kei local municipalities within the Amathole municipal district, with an acute impact on farmers’ production and generation of income. From the data, it emerged that farmers are not sufficiently informed about and do not receive specific training in drought mitigation strategies. Farmers rely on drought alleviation methods but there is a lack of adaptive strategies and timely, long-term ii state intervention. Being resource-poor, these small-scale producers are reliant on natural resources – notably water for irrigating crops. The study established further that there is neither the resources nor sufficient training by and involvement of the extension service. Farmers therefore rely on the use of drought coping mechanisms and drought mitigation techniques and on adapting their production systems. The information-sharing sessions recommended can assist in improving rural livelihoods and the productivity of small-scale vegetable farmers. The absence of engagement of youth in farming means that modern conservation and innovative farming techniques and systems are not implemented towards reducing the impacts of climate change − as well as revitalizing rural areas such Amathole. Access to education about drought, improved drought coping mechanisms and adaptive strategies should be created to facilitate an exchange of traditional and modern agricultural information. The development of infrastructure in rural communities and farming areas is another factor crucial to improving farming systems and operations in the Amathole municipal district. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2021
- Full Text: false
- Date Issued: 2021-12
Ocean structures and dynamics of two open bays on the eastern Agulhas Bank
- Authors: Dlomo, Xolisa
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/53607 , vital:45680
- Description: Upwelling, bay-scale currents, fronts and mixing in Algoa Bay and St Francis Bay occur over both short and long time periods. These physical ocean dynamics drive the temporal and spatial distribution of nutrients in the bays, there by influencing primary and secondary production. Thermal gradients and fronts are driven by the wind and open ocean influences, such as the Agulhas Current, daily and seasonal variations in solar radiation, long and short period waves, air-sea fluxes, coastal trapped waves and terrestrial freshwater inflow. These phenomena are poorly understood along this part of the coastline and were the focus of this study. I investigated the dominant temperature scales of variability in both bays, to determine which isotherm is best suited to describe temperature fluctuations and thermocline spatiotemporal variability in and between the two bays. I investigated upwelling spatiotemporal variability in the two bays and tested whether upwelling occurs at the opposite sides of the bays with a change in wind direction. Thereafter studied the occurrence and drivers of winter upwelling events. The wind-driven current spatiotemporal variability and correlations were investigated at the extremities of the two bays. The daily, intra-seasonal and yearly variation in temperature structures in Algoa Bay and St. Francis Bay were mainly driven by the local winds, coastal topography, and bathymetry. The most suitable isotherm to describe thermal fluctuations and variability in Algoa Bay shallower sites was 16.5 °C and its mean depth was 16.2 m. The best isotherm for the deeper sites in Algoa Bay was 15.7 °C with a depth of 33.1 m. The average temperature and depth of the best isotherm to describe thermal fluctuations in St. Francis Bay for the shallower sites was15.80 °C and 16.83 m, and for the deeper sites it was 15.10 °C and 32.08 m. Algoa Bay showed an average cooling trend of -0.000172 °C per year, whereas in St. Francis Bay a warming average trend of 0.0188 °C per year was observed over the study period often and six years, respectively. The wind, Coriolis Effect and Ekman Transport were the main external forces that influenced upwelling throughout the year. Since the available mesoscale indices for upwelling intensity lack the resolution needed to characterize and compare inner-shelf upwelling regimes at small spatial scales, I developed a new local, quantitative index of thermal variability. Index calculations were based on hourly records of in site depth-averaged temperatures, measured at 6 sites in St. Francis Bay and at 8 sites in Algoa Bay. Using the Multivariate Upwelling Zone Index of Cooling (MUZIC) I found that Woody Cape and Blue Horizon Bay had the highest upwelling intensity in Algoa Bay and St. Francis Bay, respectively. The other sites were ordinated and ranked according to their upwelling rates and intensity. Evidence of wind-driven winter upwelling was found to be a common occurrence in both bays. There was no obvious current seasonality observed, however, strong spectral signals in the period of a weather band (4 –7 days) were present. Current structures were generally positively correlated with wind variations in both bays. Thus, when westerly/easterly winds blew the overall surface current direction was eastward/westward. I observed a pronounced current spatiotemporal variability that was driven by local winds. The Bird Island surface currents in Algoa Bay were strongly correlated at 0–lag day with the winds, however, in Cape Recife the strongest correlations were usually observed at 1–lag day highlighting the spatiotemporal influence of wind regimes on current structures in Algoa Bay. Bird Island current speeds were higher and had an obvious bimodal directional variation (south westward /north eastward) compared to Cape Recife currents, which generally had a slower current speed with a strong west-north westward direction. In St. Francis Bay, the Schoenmakerskop surface currents showed weak positive correlation with winds at 0–lag day, however, stronger negative correlations were observed at 4–lag days. The current surface speeds in Schoenmakerskop were the lowest and varied directionally between north-north eastward and south-south eastward. The basic data requirements (i.e. SST/ UTR and ADCP time series) and the simplicity of the calculations make these indices a useful tool to apply to a large number of sites nationally and internationally, and to examine the generality of community and population-level responses to physical forcing. , Thesis (PhD) -- Faculty of Science, Journalsim and Media Studies, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Dlomo, Xolisa
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/53607 , vital:45680
- Description: Upwelling, bay-scale currents, fronts and mixing in Algoa Bay and St Francis Bay occur over both short and long time periods. These physical ocean dynamics drive the temporal and spatial distribution of nutrients in the bays, there by influencing primary and secondary production. Thermal gradients and fronts are driven by the wind and open ocean influences, such as the Agulhas Current, daily and seasonal variations in solar radiation, long and short period waves, air-sea fluxes, coastal trapped waves and terrestrial freshwater inflow. These phenomena are poorly understood along this part of the coastline and were the focus of this study. I investigated the dominant temperature scales of variability in both bays, to determine which isotherm is best suited to describe temperature fluctuations and thermocline spatiotemporal variability in and between the two bays. I investigated upwelling spatiotemporal variability in the two bays and tested whether upwelling occurs at the opposite sides of the bays with a change in wind direction. Thereafter studied the occurrence and drivers of winter upwelling events. The wind-driven current spatiotemporal variability and correlations were investigated at the extremities of the two bays. The daily, intra-seasonal and yearly variation in temperature structures in Algoa Bay and St. Francis Bay were mainly driven by the local winds, coastal topography, and bathymetry. The most suitable isotherm to describe thermal fluctuations and variability in Algoa Bay shallower sites was 16.5 °C and its mean depth was 16.2 m. The best isotherm for the deeper sites in Algoa Bay was 15.7 °C with a depth of 33.1 m. The average temperature and depth of the best isotherm to describe thermal fluctuations in St. Francis Bay for the shallower sites was15.80 °C and 16.83 m, and for the deeper sites it was 15.10 °C and 32.08 m. Algoa Bay showed an average cooling trend of -0.000172 °C per year, whereas in St. Francis Bay a warming average trend of 0.0188 °C per year was observed over the study period often and six years, respectively. The wind, Coriolis Effect and Ekman Transport were the main external forces that influenced upwelling throughout the year. Since the available mesoscale indices for upwelling intensity lack the resolution needed to characterize and compare inner-shelf upwelling regimes at small spatial scales, I developed a new local, quantitative index of thermal variability. Index calculations were based on hourly records of in site depth-averaged temperatures, measured at 6 sites in St. Francis Bay and at 8 sites in Algoa Bay. Using the Multivariate Upwelling Zone Index of Cooling (MUZIC) I found that Woody Cape and Blue Horizon Bay had the highest upwelling intensity in Algoa Bay and St. Francis Bay, respectively. The other sites were ordinated and ranked according to their upwelling rates and intensity. Evidence of wind-driven winter upwelling was found to be a common occurrence in both bays. There was no obvious current seasonality observed, however, strong spectral signals in the period of a weather band (4 –7 days) were present. Current structures were generally positively correlated with wind variations in both bays. Thus, when westerly/easterly winds blew the overall surface current direction was eastward/westward. I observed a pronounced current spatiotemporal variability that was driven by local winds. The Bird Island surface currents in Algoa Bay were strongly correlated at 0–lag day with the winds, however, in Cape Recife the strongest correlations were usually observed at 1–lag day highlighting the spatiotemporal influence of wind regimes on current structures in Algoa Bay. Bird Island current speeds were higher and had an obvious bimodal directional variation (south westward /north eastward) compared to Cape Recife currents, which generally had a slower current speed with a strong west-north westward direction. In St. Francis Bay, the Schoenmakerskop surface currents showed weak positive correlation with winds at 0–lag day, however, stronger negative correlations were observed at 4–lag days. The current surface speeds in Schoenmakerskop were the lowest and varied directionally between north-north eastward and south-south eastward. The basic data requirements (i.e. SST/ UTR and ADCP time series) and the simplicity of the calculations make these indices a useful tool to apply to a large number of sites nationally and internationally, and to examine the generality of community and population-level responses to physical forcing. , Thesis (PhD) -- Faculty of Science, Journalsim and Media Studies, 2021
- Full Text:
- Date Issued: 2021-12
An investigating of the causes of conflict in the department of employment and labour in Port Elizabeth
- Authors: Dlwati, Siphesihle
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55346 , vital:51914
- Description: The public sector in South Africa accounts for a huge amount of the public service jobs and it has been learnt that there is also a considerable amount of dysfunctional conflict that affects the public sector. The main aim of this study is to investigate the causes of conflict in the public sector, with specific reference to the department of Employment and Labour, in Port Elizabeth. The research objectives were as follows; firstly, to investigate the causes of conflict or potential conflict at the department of Employment and Labour in Port Elizabeth. Secondly, the research sought to ascertain government employees’ approach to conflict and how it affects their performance (management and subordinates) with specific reference to the department of Employment and Labour, in Port Elizabeth. Thirdly, the research also sought to come up with the recommendations with the view to address conflict or what might be causing conflict at the department of Employment and Labour in Port Elizabeth. Workplace conflict was used in this study as a conceptual framework to understand conflict in the department of Employment and Labour, in Port Elizabeth. The research has followed a qualitative approach to gather data. Using a purposive selection sampling technique, 12 semi-structured interviews were conducted with employees of the department of Employment and Labour, in Port Elizabeth. Ethical considerations were adhered to throughout the course of the study. The findings of this study have revealed that lack of consultation or lack of an inclusive or participative approach in dealing with matters is regarded as the main cause of conflict within the studied organisation. The organisations lack conflict management skills. This study can be of benefit to the organisation, in that its recommendations can assist the organisation place more attention on improving its conflict management skills, which may help reduce the negative impacts of unmanaged conflicts. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2022
- Full Text: false
- Date Issued: 2022-04
- Authors: Dlwati, Siphesihle
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55346 , vital:51914
- Description: The public sector in South Africa accounts for a huge amount of the public service jobs and it has been learnt that there is also a considerable amount of dysfunctional conflict that affects the public sector. The main aim of this study is to investigate the causes of conflict in the public sector, with specific reference to the department of Employment and Labour, in Port Elizabeth. The research objectives were as follows; firstly, to investigate the causes of conflict or potential conflict at the department of Employment and Labour in Port Elizabeth. Secondly, the research sought to ascertain government employees’ approach to conflict and how it affects their performance (management and subordinates) with specific reference to the department of Employment and Labour, in Port Elizabeth. Thirdly, the research also sought to come up with the recommendations with the view to address conflict or what might be causing conflict at the department of Employment and Labour in Port Elizabeth. Workplace conflict was used in this study as a conceptual framework to understand conflict in the department of Employment and Labour, in Port Elizabeth. The research has followed a qualitative approach to gather data. Using a purposive selection sampling technique, 12 semi-structured interviews were conducted with employees of the department of Employment and Labour, in Port Elizabeth. Ethical considerations were adhered to throughout the course of the study. The findings of this study have revealed that lack of consultation or lack of an inclusive or participative approach in dealing with matters is regarded as the main cause of conflict within the studied organisation. The organisations lack conflict management skills. This study can be of benefit to the organisation, in that its recommendations can assist the organisation place more attention on improving its conflict management skills, which may help reduce the negative impacts of unmanaged conflicts. , Thesis (MA) -- Faculty of Humanities, School of Governmental and Social Sciences, 2022
- Full Text: false
- Date Issued: 2022-04
Microstructural characterization of Swift Heavy Ion (SHI) induced rotation in single crystal NiO
- Authors: Douglas-Henry, Danielle
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/53648 , vital:45685
- Description: Swift Heavy Ions (SHI) are characterised by having energies greater than 1 MeV per nucleon with an atomic mass greater than 6 amu. Exposure to irradiation of this type has been known to produce latent tracks in insulators. This is due to the energy loss through the material being governed by electronic excitation processes. The extent of the track formation and microstructural changes induced has been reported to be material specific. Models such as the thermal spike model have been used to explain these changes, however rough approximations are still made. A particularly under studied phenomena is the collective rotation seen in materials exposed to off-normal incidence irradiation. To date the only available experimental data is X-Ray Diffraction (XRD) spectra and surface shifts. This does not allow for depth-dependent rotation studies and very little can be deduced regarding the microstructure of the modified volume. In this study, the microstructural changes in single crystal Nickel Oxide (NiO) have been studied using electron microscopy techniques. A depth dependent investigation of the crystal rotation was performed using Selected Area Electron Diffraction (SAED), Transmission Kikuchi Diffraction (TKD) and Electron Backscatter Diffraction (EBSD). Transmission Electron Microscopy (TEM) and Scanning Transmission Electron Microscopy (STEM) were utilized to interrogate the microstructural changes facilitating the bulk rotation. Five different NiO specimens were investigated. Specimens had surfaces parallel to either the {0 0 1} or {1 1 1} planes. Ion energies used were 593 MeV, 940 MeV and 1.6 GeV, while fluences ranged from 1.0 x 1011 ions/cm² to 9.6 x 1014 ions/cm². Latent track formation in both low fluence (nonoverlapping regime) and high fluence (overlapping regime) specimens were investigated and compared. , Thesis (PhD) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Douglas-Henry, Danielle
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/53648 , vital:45685
- Description: Swift Heavy Ions (SHI) are characterised by having energies greater than 1 MeV per nucleon with an atomic mass greater than 6 amu. Exposure to irradiation of this type has been known to produce latent tracks in insulators. This is due to the energy loss through the material being governed by electronic excitation processes. The extent of the track formation and microstructural changes induced has been reported to be material specific. Models such as the thermal spike model have been used to explain these changes, however rough approximations are still made. A particularly under studied phenomena is the collective rotation seen in materials exposed to off-normal incidence irradiation. To date the only available experimental data is X-Ray Diffraction (XRD) spectra and surface shifts. This does not allow for depth-dependent rotation studies and very little can be deduced regarding the microstructure of the modified volume. In this study, the microstructural changes in single crystal Nickel Oxide (NiO) have been studied using electron microscopy techniques. A depth dependent investigation of the crystal rotation was performed using Selected Area Electron Diffraction (SAED), Transmission Kikuchi Diffraction (TKD) and Electron Backscatter Diffraction (EBSD). Transmission Electron Microscopy (TEM) and Scanning Transmission Electron Microscopy (STEM) were utilized to interrogate the microstructural changes facilitating the bulk rotation. Five different NiO specimens were investigated. Specimens had surfaces parallel to either the {0 0 1} or {1 1 1} planes. Ion energies used were 593 MeV, 940 MeV and 1.6 GeV, while fluences ranged from 1.0 x 1011 ions/cm² to 9.6 x 1014 ions/cm². Latent track formation in both low fluence (nonoverlapping regime) and high fluence (overlapping regime) specimens were investigated and compared. , Thesis (PhD) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text: false
- Date Issued: 2021-12
The effect of silicon on palladium migration in pyrolytic carbon and graphite
- Authors: Downey, Justin Michael
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/53665 , vital:45684
- Description: The pebble-bed reactor (PBR) is a graphite-moderated, gas-cooled high temperature nuclear reactor design and it is one of six nuclear reactor concepts included in the Generation IV initiative. Pebble-bed reactors use spherical fuel elements (called pebbles) which consist of pyrolytic graphite (which acts as the moderator) and contain thousands of micro-fuel particles called tristructural isotropic (TRISO) particles. These TRISO fuel particles consist of a fissile material (such as U235 in oxide or carbide form) surrounded by a carbon buffer layer, a pyrolytic carbon (PyC) layer, a silicon carbide (SiC) ceramic layer for structural integrity and metallic fission product containment, and an outer PyC layer. The PBR is claimed to be a passively safe design. The commercial development of the first pebble bed reactor was that of the German AVR reactor (German: Arbeitsgemeinschaft Versuchsreaktor) developed during the 1960s. The AVR design was later updated and marketed by a company called HTR. In 1999 the South African electricity company ESKOM obtained the right to access the HTR engineering database that included details of the Siemens/Interatom HTR-Module design. ESKOM worked with HTR on a new design and dubbed it the pebble bed modular reactor (PBMR). The PBMR Co. Ltd. was formed in 1999 and mandated to license and build PBMR reactors. One of the safety considerations which emerged from research is that of metal fission product release from the TRISO fuel particles. Ag110m is a radioactive metallic fission product found to have been released from intact TRISO particles. The release of this Ag isotope is of particular concern because it is highly gamma active and has a half-life of approximately 250 days, resulting in unsafe environments for maintenance workers of PBRs. During the past four decades, many different mechanisms for Ag transport in SiC and release from TRISO particles have been proposed. A promising more recent mechanism suggests that the metallic fission product palladium (Pd) plays a significant role in the transport and release of Ag from intact TRISO particles. In this mechanism Ag transport in irradiated TRISO particle fuel takes place in the presence of the fission product Pd. The Pd reacts with the SiC layer and penetrates the SiC layer along grain boundaries to form a silicide layer which provides a rapid diffusion path for Ag in the SiC. The presence of thin silicide layers in irradiated TRISO particles was subsequently confirmed. , Thesis (PhD) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Downey, Justin Michael
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10948/53665 , vital:45684
- Description: The pebble-bed reactor (PBR) is a graphite-moderated, gas-cooled high temperature nuclear reactor design and it is one of six nuclear reactor concepts included in the Generation IV initiative. Pebble-bed reactors use spherical fuel elements (called pebbles) which consist of pyrolytic graphite (which acts as the moderator) and contain thousands of micro-fuel particles called tristructural isotropic (TRISO) particles. These TRISO fuel particles consist of a fissile material (such as U235 in oxide or carbide form) surrounded by a carbon buffer layer, a pyrolytic carbon (PyC) layer, a silicon carbide (SiC) ceramic layer for structural integrity and metallic fission product containment, and an outer PyC layer. The PBR is claimed to be a passively safe design. The commercial development of the first pebble bed reactor was that of the German AVR reactor (German: Arbeitsgemeinschaft Versuchsreaktor) developed during the 1960s. The AVR design was later updated and marketed by a company called HTR. In 1999 the South African electricity company ESKOM obtained the right to access the HTR engineering database that included details of the Siemens/Interatom HTR-Module design. ESKOM worked with HTR on a new design and dubbed it the pebble bed modular reactor (PBMR). The PBMR Co. Ltd. was formed in 1999 and mandated to license and build PBMR reactors. One of the safety considerations which emerged from research is that of metal fission product release from the TRISO fuel particles. Ag110m is a radioactive metallic fission product found to have been released from intact TRISO particles. The release of this Ag isotope is of particular concern because it is highly gamma active and has a half-life of approximately 250 days, resulting in unsafe environments for maintenance workers of PBRs. During the past four decades, many different mechanisms for Ag transport in SiC and release from TRISO particles have been proposed. A promising more recent mechanism suggests that the metallic fission product palladium (Pd) plays a significant role in the transport and release of Ag from intact TRISO particles. In this mechanism Ag transport in irradiated TRISO particle fuel takes place in the presence of the fission product Pd. The Pd reacts with the SiC layer and penetrates the SiC layer along grain boundaries to form a silicide layer which provides a rapid diffusion path for Ag in the SiC. The presence of thin silicide layers in irradiated TRISO particles was subsequently confirmed. , Thesis (PhD) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text: false
- Date Issued: 2021-12
State antiquity and early agricultural transition as deep economic roots in Africa
- Authors: Fani, Sisipho
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55487 , vital:52374
- Description: Growth economists identified that current failures and successes of economies can be traced far in their histories. The Unified Growth Model has been developed to analyse the process of development. Economic researchers have developed and identified ‘deep roots’ variables that elaborate modern growth, institutions and development. These variables include State Antiquity and Early agricultural transition. The study is an examination of the effects of State Antiquity and Early agricultural transition in the 54 African economies. The study examines these effects employing the following years: 1990, 1995, 2000, 2005, 2010, 2015, and 2020. The study employs econometric models namely, Ordinary Least Squares, Ridge and Lasso regularization models to examine the effects of these deep root variables. The study borrows baseline regressions from the works of Bockstette, Chanda and Putterman (2002), Putterman and Weil (2010) and Borcan, Olsson and Putterman (2018). This study, to the best of our knowledge, is the first to empirically examine the effects of State Antiquity and Early agricultural transition in Africa. The results of the study suggest that African economies that have low level of state antiquity experience a positive effect on modern economic growth and development whilst African economies with high levels of state antiquity experience negative effect on modern economic growth and development. The results also suggest that African economies that transition at a later stage toward agriculture experience a positive effect on modern economic growth and development. The implications of these findings indicate that state antiquity and early agricultural transition influence modern economic development only when states have reached a certain level. Countries that transitioned early towards agriculture experience a negative effect on modern economic growth and development depicting a reversal of fortune. The study recommends that the implementation of polices should corelate with the state experience of the specific economy. , Thesis (M.Com.) -- Faculty of Business and Economic Sciences, School of Economics, Development & Tourism, 2022
- Full Text:
- Authors: Fani, Sisipho
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55487 , vital:52374
- Description: Growth economists identified that current failures and successes of economies can be traced far in their histories. The Unified Growth Model has been developed to analyse the process of development. Economic researchers have developed and identified ‘deep roots’ variables that elaborate modern growth, institutions and development. These variables include State Antiquity and Early agricultural transition. The study is an examination of the effects of State Antiquity and Early agricultural transition in the 54 African economies. The study examines these effects employing the following years: 1990, 1995, 2000, 2005, 2010, 2015, and 2020. The study employs econometric models namely, Ordinary Least Squares, Ridge and Lasso regularization models to examine the effects of these deep root variables. The study borrows baseline regressions from the works of Bockstette, Chanda and Putterman (2002), Putterman and Weil (2010) and Borcan, Olsson and Putterman (2018). This study, to the best of our knowledge, is the first to empirically examine the effects of State Antiquity and Early agricultural transition in Africa. The results of the study suggest that African economies that have low level of state antiquity experience a positive effect on modern economic growth and development whilst African economies with high levels of state antiquity experience negative effect on modern economic growth and development. The results also suggest that African economies that transition at a later stage toward agriculture experience a positive effect on modern economic growth and development. The implications of these findings indicate that state antiquity and early agricultural transition influence modern economic development only when states have reached a certain level. Countries that transitioned early towards agriculture experience a negative effect on modern economic growth and development depicting a reversal of fortune. The study recommends that the implementation of polices should corelate with the state experience of the specific economy. , Thesis (M.Com.) -- Faculty of Business and Economic Sciences, School of Economics, Development & Tourism, 2022
- Full Text:
Ifuthe leelwimi kwimpumelelo yabafundi bebanga leshumi elinambini kwizifundo zejiyografi(sezelizwe) kwizikolo ezibini ezichongiweyo kwisithili saseMonti
- Authors: Gcaki, Nomnqakati
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55342 , vital:51915
- Description: Isahluko sokuqala sixoxa ngengxaki yophando esi siseko kolu phando, nemibuzo yophando kunye neenjongo zokuba isifundo esikhoyo sifuna ukufezekisa ntoni. Ngokunxulumene nengxaki ephandwayo, esi sahluko sigxile kuphononongo loncwadi ukuze kuhlolwe ubudlelwane phakathi kolwimi lokufundisa kunye nempumelelo yabafundi kwiBanga le-12 kwisifundo seJiyografi. Ukuhlolwa koncwadi kuthathwe kwimigaqo-nkqubo yokufundisa kunye neethiyori zophuhliso lokuqonda nenkcubeko. Inkqubo yeethiyori ezikhethiweyo zisetyenziselwa ukwenza ingqiqo yokuba ulwimi lokufundisa luba nefuthe njani ekufundiseni nasekukhuleni kwengqondo nokuqiqa komfundi. Ngophononongo loncwadi, umphandi unqwenela ukufumanisa ubunzima abahlangabezana nabo abafundi ekufundeni iJiyografi ngolwimi lwesiNgesi kwiBanga leshumi elinesibini. Olu phando luza kuphonononga nzulu ifuthe leelwimi kwimpumelelo yabafundi kwisifundo seJiyografi kubafundi besigaba seshumi elinambini kujoliswe kwindlela abaphumelela ngayo kwiimviwo zokuphela konyaka.Olu phando luza kujongwa kwizikolo ezibini kwiphondo leMpuma Koloni kwisithili saseMonti phakathi kweminyaka wama-2016 ukuya kuma-2018.Ngokophando esele lwenziwe, abafundi abalwimi lwabo lwasekhaya lusisiXhosa kufanele ukuba bafundiswa ngolwimi lwabo abazikhethele lona ukutsho oko isiXhosa kwaye bavavanywe kwangalo. Oku akunjalo njengoko amaphepha abo ovavanyo engolwimi lwesiNgesi, lwimi olo olufika lubabeke phantsi konxinzelelo olukhulu olubenza bangabinakho ukuzithemba nokuziva bekhululekile xa bephendula imibuzo emagumbini okufundela. Umphandi olu luvo uluseka ngengxelo ayifumene kumaxwebhu eSebe lezeMfundo (2018 NSC Chief Markers Report) yesifundo seJiyografi iphepha lokuqala. , Thesis (MA) -- Faculty of Humanities, School of Language, Media and Communication, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Gcaki, Nomnqakati
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55342 , vital:51915
- Description: Isahluko sokuqala sixoxa ngengxaki yophando esi siseko kolu phando, nemibuzo yophando kunye neenjongo zokuba isifundo esikhoyo sifuna ukufezekisa ntoni. Ngokunxulumene nengxaki ephandwayo, esi sahluko sigxile kuphononongo loncwadi ukuze kuhlolwe ubudlelwane phakathi kolwimi lokufundisa kunye nempumelelo yabafundi kwiBanga le-12 kwisifundo seJiyografi. Ukuhlolwa koncwadi kuthathwe kwimigaqo-nkqubo yokufundisa kunye neethiyori zophuhliso lokuqonda nenkcubeko. Inkqubo yeethiyori ezikhethiweyo zisetyenziselwa ukwenza ingqiqo yokuba ulwimi lokufundisa luba nefuthe njani ekufundiseni nasekukhuleni kwengqondo nokuqiqa komfundi. Ngophononongo loncwadi, umphandi unqwenela ukufumanisa ubunzima abahlangabezana nabo abafundi ekufundeni iJiyografi ngolwimi lwesiNgesi kwiBanga leshumi elinesibini. Olu phando luza kuphonononga nzulu ifuthe leelwimi kwimpumelelo yabafundi kwisifundo seJiyografi kubafundi besigaba seshumi elinambini kujoliswe kwindlela abaphumelela ngayo kwiimviwo zokuphela konyaka.Olu phando luza kujongwa kwizikolo ezibini kwiphondo leMpuma Koloni kwisithili saseMonti phakathi kweminyaka wama-2016 ukuya kuma-2018.Ngokophando esele lwenziwe, abafundi abalwimi lwabo lwasekhaya lusisiXhosa kufanele ukuba bafundiswa ngolwimi lwabo abazikhethele lona ukutsho oko isiXhosa kwaye bavavanywe kwangalo. Oku akunjalo njengoko amaphepha abo ovavanyo engolwimi lwesiNgesi, lwimi olo olufika lubabeke phantsi konxinzelelo olukhulu olubenza bangabinakho ukuzithemba nokuziva bekhululekile xa bephendula imibuzo emagumbini okufundela. Umphandi olu luvo uluseka ngengxelo ayifumene kumaxwebhu eSebe lezeMfundo (2018 NSC Chief Markers Report) yesifundo seJiyografi iphepha lokuqala. , Thesis (MA) -- Faculty of Humanities, School of Language, Media and Communication, 2022
- Full Text:
- Date Issued: 2022-04
Effect of fire severity on Afrotemperate forest tree survival
- Authors: Giddey, Brandon Louis
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55385 , vital:51988
- Description: Weather patterns have changed globally with increased fire danger weather conditions, along with poor management and fire suppression, likely contributing to the increase in prevalence of large wildfires. Ecosystems such as temperate broadleaved forests, where fire is limited by climatic conditions, are particularly at risk of altered fire regimes related to climate change. It is thus important to monitor the effects of fire in these ecosystems. Satellite remote sensing is a cost-effective way to assess spatial variability of fire effects on a landscape scale and has become an increasingly used tool for studying fire severity. In the southern Cape of South Africa during October-November 2018, a large wildfire burnt patches of Southern Cape Afrotemperate Forest (hereafter ‘Afrotemperate forest’). This provided an opportunity to investigate the accuracy of a satellite index for fire severity and the effect of fire on Afrotemperate forest survival. The first objective was to verify through field observations the accuracy of the differenced Normalised Burn Ratio (dNBR) as an index of fire severity derived from Sentinel 2 images in Afrotemperate forest. The second objective was to investigate the effect of fire severity and tree size on the post-fire survival of Afrotemperate forest tree species. For the first objective, stem fire severity, estimated from observed damage to the main stem, was recorded for 1 648 trees in 87 plots and linear regression used to test whether the observed measure of fire severity was related to dNBR. For the second objective, stem fire severity and tree survival 19-24 months post-fire were recorded for 40 species and 1 378 trees in 88 plots. Trees were considered to have survived if they resprouted from the main stem or had green foliage in the canopy. The survival response was assessed in relation to stem fire severity and tree size for all trees collectively and for 10 species (with sample size > 40) individually, using logistic regression. A strong linear relationship between dNBR and stem fire severity (r2 = 0.69, p < 0.001) confirmed the accuracy of dNBR as a measure of fire severity in Afrotemperate forest. In the fire investigated, 4 628 ha of Afrotemperate forest burnt of which 67% burnt at low severity, 21% at medium severity and 12% at high severity. The dNBR values associated with fire severity categories were comparable between Afrotemperate and North American forests, suggesting that dNBR values are relatively standard across forest types. Information on the distribution of fire severity facilitates investigation of further questions regarding past and future fire regimes and the fire ecology of Afrotemperate forest. The post-fire survival rate of Afrotemperate forest trees was 45% which is comparable to that in coniferous forests of North America but lower than that in temperate forests of Australia and Portugal and the neighbouring dune thicket which shares several species with Afrotemperate forest. Fire severity had a significant negative effect on survival and tree size a significant positive effect. Total variance explained by the model (for species collectively) was 40.8%, of which fire severity and tree size combined explained 13.2%, and species as random factor, 27.6%. Respective tree species showed differential survival responses – four species showed high survival (> 60% of individuals), while five species showed low survival (< 40%). This study was the first post-fire assessment of the resprouting ability of Afrotemperate forest trees and a third of the trees surveyed (for species collectively) resprouted from the stem. This suggested that resprouting from the stem is a primary means of post-fire recovery in Afrotemperate forest trees, in contrast with previous assertions that several common canopy species, including Podocarpus latifolius, Afrocarpus falcatus, Scutia myrtina, Scolopia mundii and Rapanea melanophloeos, are unable to resprout. Varying resilience to fire among species supports previous suggestions that fire affects species’ composition and diversity in these forests and calls for careful management of fire regimes in the face of global change. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2022
- Full Text: false
- Date Issued: 2022-04
- Authors: Giddey, Brandon Louis
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55385 , vital:51988
- Description: Weather patterns have changed globally with increased fire danger weather conditions, along with poor management and fire suppression, likely contributing to the increase in prevalence of large wildfires. Ecosystems such as temperate broadleaved forests, where fire is limited by climatic conditions, are particularly at risk of altered fire regimes related to climate change. It is thus important to monitor the effects of fire in these ecosystems. Satellite remote sensing is a cost-effective way to assess spatial variability of fire effects on a landscape scale and has become an increasingly used tool for studying fire severity. In the southern Cape of South Africa during October-November 2018, a large wildfire burnt patches of Southern Cape Afrotemperate Forest (hereafter ‘Afrotemperate forest’). This provided an opportunity to investigate the accuracy of a satellite index for fire severity and the effect of fire on Afrotemperate forest survival. The first objective was to verify through field observations the accuracy of the differenced Normalised Burn Ratio (dNBR) as an index of fire severity derived from Sentinel 2 images in Afrotemperate forest. The second objective was to investigate the effect of fire severity and tree size on the post-fire survival of Afrotemperate forest tree species. For the first objective, stem fire severity, estimated from observed damage to the main stem, was recorded for 1 648 trees in 87 plots and linear regression used to test whether the observed measure of fire severity was related to dNBR. For the second objective, stem fire severity and tree survival 19-24 months post-fire were recorded for 40 species and 1 378 trees in 88 plots. Trees were considered to have survived if they resprouted from the main stem or had green foliage in the canopy. The survival response was assessed in relation to stem fire severity and tree size for all trees collectively and for 10 species (with sample size > 40) individually, using logistic regression. A strong linear relationship between dNBR and stem fire severity (r2 = 0.69, p < 0.001) confirmed the accuracy of dNBR as a measure of fire severity in Afrotemperate forest. In the fire investigated, 4 628 ha of Afrotemperate forest burnt of which 67% burnt at low severity, 21% at medium severity and 12% at high severity. The dNBR values associated with fire severity categories were comparable between Afrotemperate and North American forests, suggesting that dNBR values are relatively standard across forest types. Information on the distribution of fire severity facilitates investigation of further questions regarding past and future fire regimes and the fire ecology of Afrotemperate forest. The post-fire survival rate of Afrotemperate forest trees was 45% which is comparable to that in coniferous forests of North America but lower than that in temperate forests of Australia and Portugal and the neighbouring dune thicket which shares several species with Afrotemperate forest. Fire severity had a significant negative effect on survival and tree size a significant positive effect. Total variance explained by the model (for species collectively) was 40.8%, of which fire severity and tree size combined explained 13.2%, and species as random factor, 27.6%. Respective tree species showed differential survival responses – four species showed high survival (> 60% of individuals), while five species showed low survival (< 40%). This study was the first post-fire assessment of the resprouting ability of Afrotemperate forest trees and a third of the trees surveyed (for species collectively) resprouted from the stem. This suggested that resprouting from the stem is a primary means of post-fire recovery in Afrotemperate forest trees, in contrast with previous assertions that several common canopy species, including Podocarpus latifolius, Afrocarpus falcatus, Scutia myrtina, Scolopia mundii and Rapanea melanophloeos, are unable to resprout. Varying resilience to fire among species supports previous suggestions that fire affects species’ composition and diversity in these forests and calls for careful management of fire regimes in the face of global change. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2022
- Full Text: false
- Date Issued: 2022-04
Youth development: a case study of vision4 mentorship programme for teenage girls in Port Elizabeth
- Authors: Gqabe, Ongeziwe Sharon
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54343 , vital:46477
- Description: Investment in youth development for a country like South Africa, where social issues such as unemployment, lack of quality education, high levels of school dropouts, difficulty in accessing post-secondary education and training are of high prevalence is crucial. There are different strategies that key players in youth development such as the government, private sector and NGOs can implement in advancing the youth. This study sought to examine one of these strategies which is mentorship. Consequently, the purpose of this study was to scrutinize the essential role that a mentorship program can play in progressing youth development. The objectives of this study are as follows: to investigate the key challenges facing the teenage girls that participated on the Vision4 Mentorship Program; to investigate the effectiveness of the strategy of using mentorship programs as a tool in achieving youth development in Motherwell, Port Elizabeth and to come up with the recommendations with the view of addressing some of the problems faced by the youth in Motherwell, Port Elizabeth. The research methodology used in this study include among others, individual interviews of participants that has been previously gone through the Vision4 Mentorship Program. Furthermore, relevant scholarly published work has been consulted to supplement the interviews. Mentorship has been used as a conceptual framework to understand the impact of mentoring to the young girls at Vision4 Mentorship Program. , Thesis (MA) -- Faculty of Humanities, Department of Sociology and Anthropology, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Gqabe, Ongeziwe Sharon
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54343 , vital:46477
- Description: Investment in youth development for a country like South Africa, where social issues such as unemployment, lack of quality education, high levels of school dropouts, difficulty in accessing post-secondary education and training are of high prevalence is crucial. There are different strategies that key players in youth development such as the government, private sector and NGOs can implement in advancing the youth. This study sought to examine one of these strategies which is mentorship. Consequently, the purpose of this study was to scrutinize the essential role that a mentorship program can play in progressing youth development. The objectives of this study are as follows: to investigate the key challenges facing the teenage girls that participated on the Vision4 Mentorship Program; to investigate the effectiveness of the strategy of using mentorship programs as a tool in achieving youth development in Motherwell, Port Elizabeth and to come up with the recommendations with the view of addressing some of the problems faced by the youth in Motherwell, Port Elizabeth. The research methodology used in this study include among others, individual interviews of participants that has been previously gone through the Vision4 Mentorship Program. Furthermore, relevant scholarly published work has been consulted to supplement the interviews. Mentorship has been used as a conceptual framework to understand the impact of mentoring to the young girls at Vision4 Mentorship Program. , Thesis (MA) -- Faculty of Humanities, Department of Sociology and Anthropology, 2021
- Full Text:
- Date Issued: 2021-12
Synthesis and characterization of iron doped sodium and potassium titanates using the pechini sol-gel method
- Authors: Guga, Aluwani
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53646 , vital:45683
- Description: Iron doped (Fe: 5Ti) sodium and potassium titanates were prepared by the Pechini sol-gel method and calcined at 800 °C. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDS), FTIR and Raman spectroscopy were used to characterize the structure and morphology of the titanate nanomaterials. A quantitative XRD analysis using Rietveld refinement of the titanates confirmed the powders to consist of crystalline phases with the Na2Ti7O15 and K2Ti8O17 phases predominant for the sodium and potassium titanate, respectively. This was further confirmed using selected area electron diffraction (SAED) in the TEM. SEM and TEM analyses indicated that the titanates are consistent with a nanostructured material exhibiting rod-like morphology. The elemental compositions of the titanites were examined by SEM-EDS and TEM-EDS and found to agree well with the targeted Fe to Ti ratio from synthesis. Limited evidence for the segregation of iron in the titanate regions were found indicating the iron to be incorporated within the titanate lattice. Electron energy loss spectroscopy (EELS) fine-structure analysis of the Fe L2,3 core-loss edge was successfully used to match the Fe to a 2+ or 3+ valence state, consistent with its occupation at Ti lattice sites. Finally, Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy were used to study the vibrational modes of the functional group of the sodium and potassium titanates. Vibrational modes consistent with previously reported findings for the titanate phases identified were found with no evidence of isolated Fe related modes. , Thesis (MSc) -- Faculty of Science, Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Guga, Aluwani
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53646 , vital:45683
- Description: Iron doped (Fe: 5Ti) sodium and potassium titanates were prepared by the Pechini sol-gel method and calcined at 800 °C. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectrometry (EDS), FTIR and Raman spectroscopy were used to characterize the structure and morphology of the titanate nanomaterials. A quantitative XRD analysis using Rietveld refinement of the titanates confirmed the powders to consist of crystalline phases with the Na2Ti7O15 and K2Ti8O17 phases predominant for the sodium and potassium titanate, respectively. This was further confirmed using selected area electron diffraction (SAED) in the TEM. SEM and TEM analyses indicated that the titanates are consistent with a nanostructured material exhibiting rod-like morphology. The elemental compositions of the titanites were examined by SEM-EDS and TEM-EDS and found to agree well with the targeted Fe to Ti ratio from synthesis. Limited evidence for the segregation of iron in the titanate regions were found indicating the iron to be incorporated within the titanate lattice. Electron energy loss spectroscopy (EELS) fine-structure analysis of the Fe L2,3 core-loss edge was successfully used to match the Fe to a 2+ or 3+ valence state, consistent with its occupation at Ti lattice sites. Finally, Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy were used to study the vibrational modes of the functional group of the sodium and potassium titanates. Vibrational modes consistent with previously reported findings for the titanate phases identified were found with no evidence of isolated Fe related modes. , Thesis (MSc) -- Faculty of Science, Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text: false
- Date Issued: 2021-12
Protean career management of independent music creatives in Gqeberha : narratives of practice
- Authors: Henneberry, Robyn
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54439 , vital:46541
- Description: This study is concerned with the promotion of local music creatives. The literature explores ways to help the independent music creatives successfully navigate in the music industry by adopting a protean career profile. The research question that was explored in the study was whether or not the independent popular female creatives in the city of Gqeberha’s music industry adopted protean career profiles for successful career navigation. These pop music creatives’ profiles were compared to those of classical creatives for further insight. Relevant literature was analysed to collect data about what international authors have discovered about creatives’ successful navigation of their careers. The information that was gleaned from the analysis indicated that numerous individuals have adopted the profile of the protean career to successfully navigate their environment. The rationale for adopting the protean career profile was that it is directly related to one’s employability. Although the working world (including the music industry) is rapidly changing, this notion of employability will enable an individual to remain updated about the latest trends in their work environment and thus successfully navigate that environment. This concept was applied to research among music creatives in the South African (SA) context. Although there was limited research on the protean career profile, the published research findings that were available indicated that employability and information were in alliance with the international research on the protean career (which constitutes one’s employability). Employing qualitative data collection procedures, the researcher interviewed 14 independent female music creatives with different backgrounds, roles and experiences. Interviews were semi-structured one-on-one as well as focus groups. This narrative strategy of inquiry helped determine whether or not these individuals had adopted the protean career for successful navigation of their working environment. After data collection the researcher engaged in a cyclical coding process for deep analysation of the data utilising atlas.ti. The data was reduced from codes to categories, and eventually towards linking categories. The findings from the study revealed that the participants’ environment (surroundings) did not sufficiently support them, the creatives do not have sufficient guidance in their music paths and not all of them had adopted the protean profile. , Thesis (MA) -- Faculty of Humanities, School of Visual and Performing Arts, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Henneberry, Robyn
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54439 , vital:46541
- Description: This study is concerned with the promotion of local music creatives. The literature explores ways to help the independent music creatives successfully navigate in the music industry by adopting a protean career profile. The research question that was explored in the study was whether or not the independent popular female creatives in the city of Gqeberha’s music industry adopted protean career profiles for successful career navigation. These pop music creatives’ profiles were compared to those of classical creatives for further insight. Relevant literature was analysed to collect data about what international authors have discovered about creatives’ successful navigation of their careers. The information that was gleaned from the analysis indicated that numerous individuals have adopted the profile of the protean career to successfully navigate their environment. The rationale for adopting the protean career profile was that it is directly related to one’s employability. Although the working world (including the music industry) is rapidly changing, this notion of employability will enable an individual to remain updated about the latest trends in their work environment and thus successfully navigate that environment. This concept was applied to research among music creatives in the South African (SA) context. Although there was limited research on the protean career profile, the published research findings that were available indicated that employability and information were in alliance with the international research on the protean career (which constitutes one’s employability). Employing qualitative data collection procedures, the researcher interviewed 14 independent female music creatives with different backgrounds, roles and experiences. Interviews were semi-structured one-on-one as well as focus groups. This narrative strategy of inquiry helped determine whether or not these individuals had adopted the protean career for successful navigation of their working environment. After data collection the researcher engaged in a cyclical coding process for deep analysation of the data utilising atlas.ti. The data was reduced from codes to categories, and eventually towards linking categories. The findings from the study revealed that the participants’ environment (surroundings) did not sufficiently support them, the creatives do not have sufficient guidance in their music paths and not all of them had adopted the protean profile. , Thesis (MA) -- Faculty of Humanities, School of Visual and Performing Arts, 2021
- Full Text:
- Date Issued: 2021-12
Development of a crumb rubber adsorbent for the sorption of lead and copper from waste water: Optimization of sorption in a binary component system
- Authors: Hlabana,Relebohile Gladys
- Date: 2022-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59688 , vital:62356
- Description: Waste tyre is becoming a global environmental problem due to challenges in its disposal management and the fact that it poses fire hazards and metal leaching risk. Waste tyre can also breed mosquitos if it traps water thereby becoming an environmental health problem. There is also a portion of unused tyre in a waste tyre that is valuable and should be recycled. In South Africa waste tyre recycling is in three industries, one of which is crumb rubber where waste tyre is applied into various sized particles called crumb rubber. Crumb rubber can be applied in environmental remediation as an organic and inorganic pollutants’ adsorbent. Considering the fact that South Africa’s environment is loaded with heavy metal pollutants due to contributions by mining and agriculture as examples, it is postulated that crumb rubber produced in South Africa could be used to remediate the environment of these toxic metals. In this study adsorption of Pb (II) and Cu (II) from the synthetic waste water using waste tyre crumb rubber produced in South Africa was studied. Crumb rubber was activated using aqueous NaOH (0.02%) to make crumb rubber wettable followed by it being treated with 0.02 % acidified KMnO4 for modification of its ability to sorp positively charged metal species. Trial sorption experiments on 50 mg / L Cu (II) were successful with sorption of over 70% in 250 minutes. Final optimization of the sorption of combined Pb (II) and Cu (II) was studied using a full factorial design and optimum conditions of sorption were found to be pH 5.4; [metal] 0.617 mmol / L for Pb (II); and pH 5.4; the optimization of Cu (II) was found to be pH 5.4; [metal] 0.777 mmol / L. In Pb (II) sorptions the mechanism of adsorption on the activated crumb rubber was found to be following the Freundlich model indicating that the adsorption seemed to occur on a multilayer adsorbent, while the mechanism of copper(II) adsorption on to the activated crumb rubber was found to be following Langmuir model, indicating that the adsorption seemed to occur on a monolayer. With adsorption percentages ranging from 98.2 % to 100.0 %, for Pb (II), the crumb rubber produced under the conditions of this study, can be used in South Africa for selective removal of Pb (II). , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2022
- Full Text:
- Date Issued: 2022-12
- Authors: Hlabana,Relebohile Gladys
- Date: 2022-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/59688 , vital:62356
- Description: Waste tyre is becoming a global environmental problem due to challenges in its disposal management and the fact that it poses fire hazards and metal leaching risk. Waste tyre can also breed mosquitos if it traps water thereby becoming an environmental health problem. There is also a portion of unused tyre in a waste tyre that is valuable and should be recycled. In South Africa waste tyre recycling is in three industries, one of which is crumb rubber where waste tyre is applied into various sized particles called crumb rubber. Crumb rubber can be applied in environmental remediation as an organic and inorganic pollutants’ adsorbent. Considering the fact that South Africa’s environment is loaded with heavy metal pollutants due to contributions by mining and agriculture as examples, it is postulated that crumb rubber produced in South Africa could be used to remediate the environment of these toxic metals. In this study adsorption of Pb (II) and Cu (II) from the synthetic waste water using waste tyre crumb rubber produced in South Africa was studied. Crumb rubber was activated using aqueous NaOH (0.02%) to make crumb rubber wettable followed by it being treated with 0.02 % acidified KMnO4 for modification of its ability to sorp positively charged metal species. Trial sorption experiments on 50 mg / L Cu (II) were successful with sorption of over 70% in 250 minutes. Final optimization of the sorption of combined Pb (II) and Cu (II) was studied using a full factorial design and optimum conditions of sorption were found to be pH 5.4; [metal] 0.617 mmol / L for Pb (II); and pH 5.4; the optimization of Cu (II) was found to be pH 5.4; [metal] 0.777 mmol / L. In Pb (II) sorptions the mechanism of adsorption on the activated crumb rubber was found to be following the Freundlich model indicating that the adsorption seemed to occur on a multilayer adsorbent, while the mechanism of copper(II) adsorption on to the activated crumb rubber was found to be following Langmuir model, indicating that the adsorption seemed to occur on a monolayer. With adsorption percentages ranging from 98.2 % to 100.0 %, for Pb (II), the crumb rubber produced under the conditions of this study, can be used in South Africa for selective removal of Pb (II). , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2022
- Full Text:
- Date Issued: 2022-12
A critical exploration of the attitudes towards and knowledge of natural resource management amongst first-year Natural Resource Management students
- Authors: Jooste, Eileen
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's , text
- Identifier: http://hdl.handle.net/10948/53666 , vital:45688
- Description: Available literature suggests that there is a need to gain more understanding of what students’ environmental attitudes and knowledge are and how they are developed by education systems. Education, in general, plays an important role in students’ attitudes and their knowledge of the world around them. It can shape students’ awareness of their natural environment and contribute to their understanding of environmental issues. Education can also strengthen students’ critical thinking, build awareness, stimulate problem solving, and promote sustainable practices. It has the potential to empower students to address global challenges from their own diverse perspectives and prepare them to uphold the economy. Education can improve and maintain societal wellbeing and can help students to maintain the natural environment, along with achieving sustainable development. Environmental education, specifically, can play a big role in how students deal with the natural environment. The primary aim of this qualitative research study was to examine first-year students’ environmental attitudes and knowledge in the School of Natural Resource Management at the Nelson Mandela University George Campus, South Africa. First-year students’ environmental attitudes and knowledge were examined as they entered the university, and then again at the end of the first semester once they had completed a module in ecology. More specifically, at the outset of the research the objectives were (1) to establish an understanding of the baseline environmental attitudes and knowledge of first-year students who were undertaking three ecological modules being offered by the School of Natural Resource Management; (2) to assess the changes in the first-year students’ environmental attitudes and knowledge, using a post-intervention strategy; (3) to understand what type of teaching approaches were used by the lecturers teaching the ecological modules; and (4) to evaluate how the teaching approaches of the lecturers influenced the baseline environmental attitudes and knowledge of the student group. This research took place in the midst of the Corona Virus pandemic, which had significantly influenced the teaching and learning environment. Multiple education systems, including those of the Nelson Mandela University George Campus, had to rapidly transition to online teaching and learning. So, although unplanned for, this research could not ignore the rapid transition to online teaching and learning and the role it played in shaping the first-year School of Natural Resource Management students’ environmental attitudes and knowledge. It also impacted the teaching approaches of the environmental lecturers. An additional objective in response to the rapid transition to online teaching and learning was, therefore, added: (5) to understand the experiences of the first-year School of Natural Resource Management students and the three environmental lecturers who had to rapidly transition to online teaching and learning. Data was collected via questionnaires and semi-structured interviews with students and staff in the School of Natural Resource Management at Nelson Mandela University George Campus within three different natural resource management programs, namely Agriculture, Nature Conservation, and Forestry. Baseline questionnaires were conducted with 107 students for a baseline assessment as the students entered the university. An online post-intervention questionnaire was conducted with 33 of the initial group of students at the end of the semester for a post-intervention assessment. In-depth semi-structured interviews were conducted with three environmental lectures before they taught their three ecology modules in each of the programs. Additional online semi-structured interviews were also done with the same three environmental lectures after the rapid transition to online teaching and learning took place. The significant findings from this research were analyzed and discussed. This included the baseline environmental attitudes and knowledge of the student body upon arrival at the university and the changes in their environmental attitudes and knowledge after they were exposed to the ecology modules taught in each of the programs. The discussion also included the teaching approaches adopted by the environmental lecturers and the influence their teaching approaches had on the students’ environmental attitudes and knowledge. In addition, the results shed light on the experiences of students and lecturers during the rapid transition to online teaching and learning. The main conclusions reached were that the first-year School of Natural Resource Management students did not have a deep understanding of ecological concepts prior to arriving at university, but they did show a concern for the natural environment. Their lack of understanding was reduced as the students progressed with the ecology module. A greater understanding resulted in a change in students’ perspectives on the ecological module, their program, and the industry they were preparing to enter after being exposed to the ecology module. The environmental lecturers’ teaching approaches contributed to improving the students’ environmental attitudes and knowledge. When it came to the rapid transition to online teaching and learning, both the first-year School of Natural Resource Management students and environmental lecturers experienced benefits and challenges. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Jooste, Eileen
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's , text
- Identifier: http://hdl.handle.net/10948/53666 , vital:45688
- Description: Available literature suggests that there is a need to gain more understanding of what students’ environmental attitudes and knowledge are and how they are developed by education systems. Education, in general, plays an important role in students’ attitudes and their knowledge of the world around them. It can shape students’ awareness of their natural environment and contribute to their understanding of environmental issues. Education can also strengthen students’ critical thinking, build awareness, stimulate problem solving, and promote sustainable practices. It has the potential to empower students to address global challenges from their own diverse perspectives and prepare them to uphold the economy. Education can improve and maintain societal wellbeing and can help students to maintain the natural environment, along with achieving sustainable development. Environmental education, specifically, can play a big role in how students deal with the natural environment. The primary aim of this qualitative research study was to examine first-year students’ environmental attitudes and knowledge in the School of Natural Resource Management at the Nelson Mandela University George Campus, South Africa. First-year students’ environmental attitudes and knowledge were examined as they entered the university, and then again at the end of the first semester once they had completed a module in ecology. More specifically, at the outset of the research the objectives were (1) to establish an understanding of the baseline environmental attitudes and knowledge of first-year students who were undertaking three ecological modules being offered by the School of Natural Resource Management; (2) to assess the changes in the first-year students’ environmental attitudes and knowledge, using a post-intervention strategy; (3) to understand what type of teaching approaches were used by the lecturers teaching the ecological modules; and (4) to evaluate how the teaching approaches of the lecturers influenced the baseline environmental attitudes and knowledge of the student group. This research took place in the midst of the Corona Virus pandemic, which had significantly influenced the teaching and learning environment. Multiple education systems, including those of the Nelson Mandela University George Campus, had to rapidly transition to online teaching and learning. So, although unplanned for, this research could not ignore the rapid transition to online teaching and learning and the role it played in shaping the first-year School of Natural Resource Management students’ environmental attitudes and knowledge. It also impacted the teaching approaches of the environmental lecturers. An additional objective in response to the rapid transition to online teaching and learning was, therefore, added: (5) to understand the experiences of the first-year School of Natural Resource Management students and the three environmental lecturers who had to rapidly transition to online teaching and learning. Data was collected via questionnaires and semi-structured interviews with students and staff in the School of Natural Resource Management at Nelson Mandela University George Campus within three different natural resource management programs, namely Agriculture, Nature Conservation, and Forestry. Baseline questionnaires were conducted with 107 students for a baseline assessment as the students entered the university. An online post-intervention questionnaire was conducted with 33 of the initial group of students at the end of the semester for a post-intervention assessment. In-depth semi-structured interviews were conducted with three environmental lectures before they taught their three ecology modules in each of the programs. Additional online semi-structured interviews were also done with the same three environmental lectures after the rapid transition to online teaching and learning took place. The significant findings from this research were analyzed and discussed. This included the baseline environmental attitudes and knowledge of the student body upon arrival at the university and the changes in their environmental attitudes and knowledge after they were exposed to the ecology modules taught in each of the programs. The discussion also included the teaching approaches adopted by the environmental lecturers and the influence their teaching approaches had on the students’ environmental attitudes and knowledge. In addition, the results shed light on the experiences of students and lecturers during the rapid transition to online teaching and learning. The main conclusions reached were that the first-year School of Natural Resource Management students did not have a deep understanding of ecological concepts prior to arriving at university, but they did show a concern for the natural environment. Their lack of understanding was reduced as the students progressed with the ecology module. A greater understanding resulted in a change in students’ perspectives on the ecological module, their program, and the industry they were preparing to enter after being exposed to the ecology module. The environmental lecturers’ teaching approaches contributed to improving the students’ environmental attitudes and knowledge. When it came to the rapid transition to online teaching and learning, both the first-year School of Natural Resource Management students and environmental lecturers experienced benefits and challenges. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2021
- Full Text:
- Date Issued: 2021-12
Mangrove response to water level changes at the Nxaxo-Ngqusi and St Lucia Estuaries
- Authors: Julie, Corianna Lauren
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53644 , vital:45689
- Description: Water level variability within an estuary can vary as a function of tides (inundation frequency and duration) and rainfall, acting as one of the main determinants of mangrove growth, diversity, productivity, and distribution. Understanding how mangroves respond in estuaries to water level variability provides baseline information which can be used to predict future changes in mangrove growth and distribution in response to this driver This study measured mangrove characteristics (growth, structure, and areal extent) in two estuaries that differed in tidal setting, and thus water variability; the Nxaxo-Ngqusi and St Lucia estuaries, South Africa. These estuaries are part of a long-term monitoring programme (2010 - 2020) that has recorded mangrove responses to environmental changes. At the Nxaxo-Ngqusi Estuary, long-tem sea-level data (2003 – 2018) collected from the nearest tide gauge, and mangrove growth and areal extent were used to assess mangrove characteristics in a permanently open, micro tidal setting.Additionally, short-term water level data (August 2019 – September 2020), measured with in situ loggers, and sediment input at different sites within the mangrove forest, were also measured. Data was collected along the main channel sites, and at previously set up cattle exclusion plots ( browsed and non-browsed sites set to establish the effect of cattle browsing on mangroves). Similarly, at the St Lucia Estuary, long term water level data (2004 – 2020) collected at the bridge in the lower reaches of the estuary by Ezemvelo KZN-Wildlife, and annual mangrove growth, structure and areal extent data were used to assess mangrove characteristics in an estuarine lake that undergoes cycles between hypersaline and freshwater-dominated states. The results showed that mangrove responses to water level changes are complex and depend on several factors such as estuary mouth dynamics, anthropogenic activities, and site-level environmental conditions. The first objective was to compare water level changes and mangrove structure (mangrove height, and pneumatophore characteristics such as height, density and % aerenchyma) and sediment input between different sites at each estuary. Mangrove growth was higher at sites where longer inundation and higher inundation frequency were recorded at the Nxaxo-Ngqusi Estuary. However,longer inundation periods under closed mouth conditions resulted in stunted growth and mangrove dieback at St Lucia Estuary. At the Nxaxo-Ngqusi Estuary, mangroves at the main channel sites, closer to the water’s edge, had an overall higher growth rate (2.8 – 45.9 cm yr-1) than the mangroves found at the browsed (0 – 25 cm yr-1) and non-browsed sites (0 – 25.3 cm yr-1) on the landward edge of the forest. The effect of cattle browsing at these sites forms part of a long-term monitoring programme and this disturbance could have also influenced the results. Mangrove growth rate was higher in years with more rainfall at all sites within the estuary. At the St Lucia Estuary, mangrove growth rate was highest (0.81 cm yr-1) at a lower mean water level range (0.13 – 1.72 m) between 2010 - 2015, and growth rate was lowest (1.3 cm yr-1) in higher mean water level range conditions (0.34 m – 2.18 m) between 2015 – 2020. When water levels increased by up to 1.1 m due to closed mouth conditions, this led to extensive mangrove dieback further upstream by 2015. The maximum tidal flooding depth and inundation period influenced pneumatophore structure (height, density, and % aerenchyma) at the Nxaxo-Ngqusi Estuary. Sediment accumulation was highest at sites with increased pneumatophore density, but accumulation rates at the Nxaxo-Ngqusi Estuary (0.4 – 0.7 g over a high tide lasting 4-5 hours) were low and did not lead to smothering of the pneumatophores. Total sediment accumulation was highest at sites that experienced greater flooding depths. Increased inundation at the St Lucia Estuary caused inundation stress which led to mangrove mortality. This is because these mangroves are found in a closed estuary where increased water levels lead to prolonged submergence of the pneumatophores. A decrease in mangrove area was recorded at both sites. Low rainfall coupled with cattle browsing caused a decrease in mangrove area of 22% between 2009 and 2019, particularly along the mangrove fringe area at the Nxaxo-Ngqusi Estuary. The mangroves at the St Lucia Estuary, however, experienced mangrove dieback at all sites, with Site 1 recording the greatest percentage decrease in area of 71.7 % (loss of 44.76 ha) between 2010 and 2020. This was related to the progressive increase of freshwater input and water level at St Lucia Estuary under closed mouth conditions. The years leading up to 2019 had peaks in water levels at the St Lucia Estuary, with the highest water level of 2.12 m in 2019 since 2002. As a consequence, there was increased reed growth, where reeds expanded by 58% (177 ha) due to the high influx of freshwater, and no tidal exchange, which occurred in conjunction with a loss of 60.% (42 ha) of the original mangrove extent at the St Lucia Estuary. This study shows that increased water level changes (inundation frequency and duration) at the Nxaxo-Ngqusi Estuary maintain healthy mangrove stands. This is in contrast to the St Lucia Estuary, where there was a loss of mangroves as a result of high water levels under closed mouth conditions. Mangrove growth and extent at the Nxaxo-Ngqusi Estuary fluctuated in response to drought, and trampling and browsing by livestock. Extensive inundation and lack of tidal exchange reduced mangrove growth and extent at the St Lucia Estuary, with mangrove dieback occurring at all sites. These two systems are representative of the dynamic conditions found in South African estuaries. These research findings suggest that the continuous effects of climate change on estuarine habitats could result in changes in estuary mouth dynamics, which could impact mangrove growth, structure, and extent. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Julie, Corianna Lauren
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53644 , vital:45689
- Description: Water level variability within an estuary can vary as a function of tides (inundation frequency and duration) and rainfall, acting as one of the main determinants of mangrove growth, diversity, productivity, and distribution. Understanding how mangroves respond in estuaries to water level variability provides baseline information which can be used to predict future changes in mangrove growth and distribution in response to this driver This study measured mangrove characteristics (growth, structure, and areal extent) in two estuaries that differed in tidal setting, and thus water variability; the Nxaxo-Ngqusi and St Lucia estuaries, South Africa. These estuaries are part of a long-term monitoring programme (2010 - 2020) that has recorded mangrove responses to environmental changes. At the Nxaxo-Ngqusi Estuary, long-tem sea-level data (2003 – 2018) collected from the nearest tide gauge, and mangrove growth and areal extent were used to assess mangrove characteristics in a permanently open, micro tidal setting.Additionally, short-term water level data (August 2019 – September 2020), measured with in situ loggers, and sediment input at different sites within the mangrove forest, were also measured. Data was collected along the main channel sites, and at previously set up cattle exclusion plots ( browsed and non-browsed sites set to establish the effect of cattle browsing on mangroves). Similarly, at the St Lucia Estuary, long term water level data (2004 – 2020) collected at the bridge in the lower reaches of the estuary by Ezemvelo KZN-Wildlife, and annual mangrove growth, structure and areal extent data were used to assess mangrove characteristics in an estuarine lake that undergoes cycles between hypersaline and freshwater-dominated states. The results showed that mangrove responses to water level changes are complex and depend on several factors such as estuary mouth dynamics, anthropogenic activities, and site-level environmental conditions. The first objective was to compare water level changes and mangrove structure (mangrove height, and pneumatophore characteristics such as height, density and % aerenchyma) and sediment input between different sites at each estuary. Mangrove growth was higher at sites where longer inundation and higher inundation frequency were recorded at the Nxaxo-Ngqusi Estuary. However,longer inundation periods under closed mouth conditions resulted in stunted growth and mangrove dieback at St Lucia Estuary. At the Nxaxo-Ngqusi Estuary, mangroves at the main channel sites, closer to the water’s edge, had an overall higher growth rate (2.8 – 45.9 cm yr-1) than the mangroves found at the browsed (0 – 25 cm yr-1) and non-browsed sites (0 – 25.3 cm yr-1) on the landward edge of the forest. The effect of cattle browsing at these sites forms part of a long-term monitoring programme and this disturbance could have also influenced the results. Mangrove growth rate was higher in years with more rainfall at all sites within the estuary. At the St Lucia Estuary, mangrove growth rate was highest (0.81 cm yr-1) at a lower mean water level range (0.13 – 1.72 m) between 2010 - 2015, and growth rate was lowest (1.3 cm yr-1) in higher mean water level range conditions (0.34 m – 2.18 m) between 2015 – 2020. When water levels increased by up to 1.1 m due to closed mouth conditions, this led to extensive mangrove dieback further upstream by 2015. The maximum tidal flooding depth and inundation period influenced pneumatophore structure (height, density, and % aerenchyma) at the Nxaxo-Ngqusi Estuary. Sediment accumulation was highest at sites with increased pneumatophore density, but accumulation rates at the Nxaxo-Ngqusi Estuary (0.4 – 0.7 g over a high tide lasting 4-5 hours) were low and did not lead to smothering of the pneumatophores. Total sediment accumulation was highest at sites that experienced greater flooding depths. Increased inundation at the St Lucia Estuary caused inundation stress which led to mangrove mortality. This is because these mangroves are found in a closed estuary where increased water levels lead to prolonged submergence of the pneumatophores. A decrease in mangrove area was recorded at both sites. Low rainfall coupled with cattle browsing caused a decrease in mangrove area of 22% between 2009 and 2019, particularly along the mangrove fringe area at the Nxaxo-Ngqusi Estuary. The mangroves at the St Lucia Estuary, however, experienced mangrove dieback at all sites, with Site 1 recording the greatest percentage decrease in area of 71.7 % (loss of 44.76 ha) between 2010 and 2020. This was related to the progressive increase of freshwater input and water level at St Lucia Estuary under closed mouth conditions. The years leading up to 2019 had peaks in water levels at the St Lucia Estuary, with the highest water level of 2.12 m in 2019 since 2002. As a consequence, there was increased reed growth, where reeds expanded by 58% (177 ha) due to the high influx of freshwater, and no tidal exchange, which occurred in conjunction with a loss of 60.% (42 ha) of the original mangrove extent at the St Lucia Estuary. This study shows that increased water level changes (inundation frequency and duration) at the Nxaxo-Ngqusi Estuary maintain healthy mangrove stands. This is in contrast to the St Lucia Estuary, where there was a loss of mangroves as a result of high water levels under closed mouth conditions. Mangrove growth and extent at the Nxaxo-Ngqusi Estuary fluctuated in response to drought, and trampling and browsing by livestock. Extensive inundation and lack of tidal exchange reduced mangrove growth and extent at the St Lucia Estuary, with mangrove dieback occurring at all sites. These two systems are representative of the dynamic conditions found in South African estuaries. These research findings suggest that the continuous effects of climate change on estuarine habitats could result in changes in estuary mouth dynamics, which could impact mangrove growth, structure, and extent. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2021
- Full Text: false
- Date Issued: 2021-12
Real-time feedback model for supporting individualised learning of programming students
- Authors: Keen, Charne
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53624 , vital:45691
- Description: Feedback is crucial to the enhancement of the learning and teaching environment, especially in those environments that suffer from a number of extrinsic challenges. The growing demands for educators to provide academic interventions throughout the lecture session and the need for continuous improvement of the quality of university education make it necessary to find and apply more effective and efficient educational technologies and practices based on the correlation of teaching with a student’s conceptual understanding and individual learning preference. Following a combination of Design Science Research (DSR) and Case Study Methodology, this research addresses this problem by designing a technology based real-time feedback (TBRTF) model that can easily be implemented in a South African University. The model designed followed a layered architecture pattern. The architecture describes the data, technology and user support layers of the model. The data support layer incorporates the collection of student academic data and learning preferences. The technology incorporates a machine learning component. The machine learning component covers two technological aspects: the prediction component and the clustering component. This TBRTF model provides the guidelines needed to develop a system that supports individualised real-time feedback in the learning and teaching environment of programming students. The aim of the model is that as the students partake in learning activities where the student data is updated, the monitoring component will fire, updating the probability of failure prediction and in turn the student clusters are regenerated. This will notify the educator of a change and provide decision making support. The student will be allocated individualised feedback in the form of learning materials based on the cluster that the student is allocated to. Through a demonstration and evaluation, this study showed that by following the proposed architecture of the TBRTF model, a model that supports individualised realtime feedback in the learning and teaching environment of programming students can be developed. The validation used an artificial neural network as the prediction component and a k-means clustering algorithm as the clustering component. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text: false
- Date Issued: 2021-12
- Authors: Keen, Charne
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53624 , vital:45691
- Description: Feedback is crucial to the enhancement of the learning and teaching environment, especially in those environments that suffer from a number of extrinsic challenges. The growing demands for educators to provide academic interventions throughout the lecture session and the need for continuous improvement of the quality of university education make it necessary to find and apply more effective and efficient educational technologies and practices based on the correlation of teaching with a student’s conceptual understanding and individual learning preference. Following a combination of Design Science Research (DSR) and Case Study Methodology, this research addresses this problem by designing a technology based real-time feedback (TBRTF) model that can easily be implemented in a South African University. The model designed followed a layered architecture pattern. The architecture describes the data, technology and user support layers of the model. The data support layer incorporates the collection of student academic data and learning preferences. The technology incorporates a machine learning component. The machine learning component covers two technological aspects: the prediction component and the clustering component. This TBRTF model provides the guidelines needed to develop a system that supports individualised real-time feedback in the learning and teaching environment of programming students. The aim of the model is that as the students partake in learning activities where the student data is updated, the monitoring component will fire, updating the probability of failure prediction and in turn the student clusters are regenerated. This will notify the educator of a change and provide decision making support. The student will be allocated individualised feedback in the form of learning materials based on the cluster that the student is allocated to. Through a demonstration and evaluation, this study showed that by following the proposed architecture of the TBRTF model, a model that supports individualised realtime feedback in the learning and teaching environment of programming students can be developed. The validation used an artificial neural network as the prediction component and a k-means clustering algorithm as the clustering component. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text: false
- Date Issued: 2021-12
An aesthetic exploration of skin as the abject other
- Knickelbein, Jonel, Wentzel, Andrieta
- Authors: Knickelbein, Jonel , Wentzel, Andrieta
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55341 , vital:51913
- Description: The purpose of this dissertation is to explore the notion of skin, its functions, and dysfunctions as the basis for the conceptual as well as theoretical output of this work. The problem statement aims to establish whether cathartic relief can be achieved through the process of visualizing skin as the abject other. Every human and animal is born with skin. The epidermis is the outermost of three layers that make up the skin. This layer provides a barrier to infection from environmental pathogens and regulates the amount of water released from the body into the atmosphere through trans epidermal water loss (Bouwstra, 2003:34). Although the human skin serves as a protective barrier, the skin itself can be a source of physical as well as emotional pain. I was born with Epidermolysis Bullosa (EB), a rare and genetic skin condition that results in extensive blistering and wounding of the skin caused by mechanical trauma. The process of friction, wounding and healing has been a part of my physical being and daily affairs since I can remember. According to Cervero, ―Pain is our most powerful emotion, an essential learning tool, a major factor in our relationship with the world, and the source of much of our social behavior‖ (2012:34).I believe that my personal experience with EB has affected how I view the functions and importance of skin. In this study I explore the purposes and functions of skin through both a physical and psychological lense I also investigate the role skin plays in forming identity. The works of artists such as Frida Kahlo, Eva Hesse and Alina Szapocznikow are carefully considered in understanding different approaches and mediums used in engaging with the experience of catharsis. Investigations are made into theories on Abjection, the Skin-Ego, Materiality and Catharsis in order to sufficiently inform and shape the outcomes of the creative process. The creative and research processes have resulted in the body of artwork, entitled Skin- deep: transforming dysfunction into function, which is presented as a narrative installation and exhibition of abstract sculptural work. Ultimately, the body of work and research attempts to validate that the notion of skin (as the abject other skin) can be artistically explored to achieve cathartic relief. , Thesis (MA) -- Faculty of Humanities, School of Visual and Performing Arts, 2022
- Full Text: false
- Date Issued: 2022-04
- Authors: Knickelbein, Jonel , Wentzel, Andrieta
- Date: 2022-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/55341 , vital:51913
- Description: The purpose of this dissertation is to explore the notion of skin, its functions, and dysfunctions as the basis for the conceptual as well as theoretical output of this work. The problem statement aims to establish whether cathartic relief can be achieved through the process of visualizing skin as the abject other. Every human and animal is born with skin. The epidermis is the outermost of three layers that make up the skin. This layer provides a barrier to infection from environmental pathogens and regulates the amount of water released from the body into the atmosphere through trans epidermal water loss (Bouwstra, 2003:34). Although the human skin serves as a protective barrier, the skin itself can be a source of physical as well as emotional pain. I was born with Epidermolysis Bullosa (EB), a rare and genetic skin condition that results in extensive blistering and wounding of the skin caused by mechanical trauma. The process of friction, wounding and healing has been a part of my physical being and daily affairs since I can remember. According to Cervero, ―Pain is our most powerful emotion, an essential learning tool, a major factor in our relationship with the world, and the source of much of our social behavior‖ (2012:34).I believe that my personal experience with EB has affected how I view the functions and importance of skin. In this study I explore the purposes and functions of skin through both a physical and psychological lense I also investigate the role skin plays in forming identity. The works of artists such as Frida Kahlo, Eva Hesse and Alina Szapocznikow are carefully considered in understanding different approaches and mediums used in engaging with the experience of catharsis. Investigations are made into theories on Abjection, the Skin-Ego, Materiality and Catharsis in order to sufficiently inform and shape the outcomes of the creative process. The creative and research processes have resulted in the body of artwork, entitled Skin- deep: transforming dysfunction into function, which is presented as a narrative installation and exhibition of abstract sculptural work. Ultimately, the body of work and research attempts to validate that the notion of skin (as the abject other skin) can be artistically explored to achieve cathartic relief. , Thesis (MA) -- Faculty of Humanities, School of Visual and Performing Arts, 2022
- Full Text: false
- Date Issued: 2022-04