A 150 MHz all sky survey with the Precision Array to Probe the Epoch of Reionization
- Authors: Chege, James Kariuki
- Date: 2020
- Subjects: Epoch of reionization -- Research , Astronomy -- Observations , Radio interferometers
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/117733 , vital:34556
- Description: The Precision Array to Probe the Epoch of Reionization (PAPER) was built to measure the redshifted 21 cm line of hydrogen from cosmic reionization. Such low frequency observations promise to be the best means of understanding the cosmic dawn; when the first galaxies in the universe formed, and also the Epoch of Reionization; when the intergalactic medium changed from neutral to ionized. The major challenges to these observations is the presence of astrophysical foregrounds that are much brighter than the cosmological signal. Here, I present an all-sky survey at 150 MHz obtained from the analysis of 300 hours of PAPER observations. Particular focus is given to the calibration and imaging techniques that need to deal with the wide field of view of a non-tracking instrument. The survey covers ~ 7000 square degrees of the southern sky. From a sky area of 4400 square degrees out of the total survey area, I extract a catalogue of sources brighter than 4 Jy whose accuracy was tested against the published GLEAM catalogue, leading to a fractional difference rms better than 20%. The catalogue provides an all-sky accurate model of the extragalactic foreground to be used for the calibration of future Epoch of Reionization observations and to be subtracted from the PAPER observations themselves in order to mitigate the foreground contamination.
- Full Text:
- Date Issued: 2020
- Authors: Chege, James Kariuki
- Date: 2020
- Subjects: Epoch of reionization -- Research , Astronomy -- Observations , Radio interferometers
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/117733 , vital:34556
- Description: The Precision Array to Probe the Epoch of Reionization (PAPER) was built to measure the redshifted 21 cm line of hydrogen from cosmic reionization. Such low frequency observations promise to be the best means of understanding the cosmic dawn; when the first galaxies in the universe formed, and also the Epoch of Reionization; when the intergalactic medium changed from neutral to ionized. The major challenges to these observations is the presence of astrophysical foregrounds that are much brighter than the cosmological signal. Here, I present an all-sky survey at 150 MHz obtained from the analysis of 300 hours of PAPER observations. Particular focus is given to the calibration and imaging techniques that need to deal with the wide field of view of a non-tracking instrument. The survey covers ~ 7000 square degrees of the southern sky. From a sky area of 4400 square degrees out of the total survey area, I extract a catalogue of sources brighter than 4 Jy whose accuracy was tested against the published GLEAM catalogue, leading to a fractional difference rms better than 20%. The catalogue provides an all-sky accurate model of the extragalactic foreground to be used for the calibration of future Epoch of Reionization observations and to be subtracted from the PAPER observations themselves in order to mitigate the foreground contamination.
- Full Text:
- Date Issued: 2020
A Bayesian approach to tilted-ring modelling of galaxies
- Authors: Maina, Eric Kamau
- Date: 2020
- Subjects: Bayesian statistical decision theory , Galaxies , Radio astronomy , TiRiFiC (Tilted Ring Fitting Code) , Neutral hydrogen , Spectroscopic data cubes , Galaxy parametrisation
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/145783 , vital:38466
- Description: The orbits of neutral hydrogen (H I) gas found in most disk galaxies are circular and also exhibit long-lived warps at large radii where the restoring gravitational forces of the inner disk become weak (Spekkens and Giovanelli 2006). These warps make the tilted-ring model an ideal choice for galaxy parametrisation. Analysis software utilizing the tilted-ring-model can be grouped into two and three-dimensional based software. Józsa et al. (2007b) demonstrated that three dimensional based software is better suited for galaxy parametrisation because it is affected by the effect of beam smearing only by increasing the uncertainty of parameters but not with the notorious systematic effects observed for two-dimensional fitting techniques. TiRiFiC, The Tilted Ring Fitting Code (Józsa et al. 2007b), is a software to construct parameterised models of high-resolution data cubes of rotating galaxies. It uses the tilted-ring model, and with that, a combination of some parameters such as surface brightness, position angle, rotation velocity and inclination, to describe galaxies. TiRiFiC works by directly fitting tilted-ring models to spectroscopic data cubes and hence is not affected by beam smearing or line-of-site-effects, e.g. strong warps. Because of that, the method is unavoidable as an analytic method in future Hi surveys. In the current implementation, though, there are several drawbacks. The implemented optimisers search for local solutions in parameter space only, do not quantify correlations between parameters and cannot find errors of single parameters. In theory, these drawbacks can be overcome by using Bayesian statistics, implemented in Multinest (Feroz et al. 2008), as it allows for sampling a posterior distribution irrespective of its multimodal nature resulting in parameter samples that correspond to the maximum in the posterior distribution. These parameter samples can be used as well to quantify correlations and find errors of single parameters. Since this method employs Bayesian statistics, it also allows the user to leverage any prior information they may have on parameter values.
- Full Text:
- Date Issued: 2020
- Authors: Maina, Eric Kamau
- Date: 2020
- Subjects: Bayesian statistical decision theory , Galaxies , Radio astronomy , TiRiFiC (Tilted Ring Fitting Code) , Neutral hydrogen , Spectroscopic data cubes , Galaxy parametrisation
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/145783 , vital:38466
- Description: The orbits of neutral hydrogen (H I) gas found in most disk galaxies are circular and also exhibit long-lived warps at large radii where the restoring gravitational forces of the inner disk become weak (Spekkens and Giovanelli 2006). These warps make the tilted-ring model an ideal choice for galaxy parametrisation. Analysis software utilizing the tilted-ring-model can be grouped into two and three-dimensional based software. Józsa et al. (2007b) demonstrated that three dimensional based software is better suited for galaxy parametrisation because it is affected by the effect of beam smearing only by increasing the uncertainty of parameters but not with the notorious systematic effects observed for two-dimensional fitting techniques. TiRiFiC, The Tilted Ring Fitting Code (Józsa et al. 2007b), is a software to construct parameterised models of high-resolution data cubes of rotating galaxies. It uses the tilted-ring model, and with that, a combination of some parameters such as surface brightness, position angle, rotation velocity and inclination, to describe galaxies. TiRiFiC works by directly fitting tilted-ring models to spectroscopic data cubes and hence is not affected by beam smearing or line-of-site-effects, e.g. strong warps. Because of that, the method is unavoidable as an analytic method in future Hi surveys. In the current implementation, though, there are several drawbacks. The implemented optimisers search for local solutions in parameter space only, do not quantify correlations between parameters and cannot find errors of single parameters. In theory, these drawbacks can be overcome by using Bayesian statistics, implemented in Multinest (Feroz et al. 2008), as it allows for sampling a posterior distribution irrespective of its multimodal nature resulting in parameter samples that correspond to the maximum in the posterior distribution. These parameter samples can be used as well to quantify correlations and find errors of single parameters. Since this method employs Bayesian statistics, it also allows the user to leverage any prior information they may have on parameter values.
- Full Text:
- Date Issued: 2020
A business process model for blockchain-based South African real estate transactions
- Authors: Tilbury, Jack Laurie
- Date: 2020
- Subjects: Blockchains (Databases) , Conveyancing -- Technological innovations , Real estate business -- Data processing , Real estate business -- South Africa -- Technological innovations
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/148380 , vital:38734
- Description: The real estate transaction process has been described as inefficient and technologically outdated due to numerous stakeholders and predominantly paper-based operations. Despite the apparent bottlenecks in the current process, the implementation of new technology into the real estate sector has lagged. Several attempts have been made to modernise and digitise the business process but committed integration of assisting technology has lacked attention. This study examined the applicability and potential integration of blockchain technology into the business process of South African real estate transactions. Blockchain’s novelty means that research in this space, especially within South Africa, is limited. Of the research that has been conducted, no models of the business processes for South African or blockchain-based real estate transactions have been constructed. This study provides two business process models, illustrating the two different processes. The main contribution of this paper was an integrated business process model, illustrating how the various processes and stakeholder interactions for South African blockchain-based real estate transactions are conducted on one transaction platform, common to all participating stakeholders. This platform was named the South African Blockchain Land Exchange System (SABLES), which manages and facilitates these transactions in their entirety from start to finish. This model depicts an enhanced business process that provides increased security, transparency, and speed. These benefits will be realised by those who register, adopt, and transact on the platform. Through in-depth interviews, the integrated business process model was assessed. The findings produced a final and combined thematic map, representing the main themes of the analysed interview data, namely blockchain implementation strategies, business process applicability, information technology assimilation, current transaction context, and PropTech 3.0 success factors. The discussion revealed that the current transaction process lacks technological innovation, which increases pressure on the conveyancing role. It was also revealed that there is not only a need within the industry, but a desire, for newer technologies to assist the transaction process. In order to streamline and improve efficiency, business processes should leverage digital records and data, and strive for a solution beyond digitisation, achieving digitalisation. Digitalisation recognises digital documents as official and legal documents as opposed to simply being digital back-ups. This, coupled with the business process models, represent theoretical contributions.
- Full Text:
- Date Issued: 2020
- Authors: Tilbury, Jack Laurie
- Date: 2020
- Subjects: Blockchains (Databases) , Conveyancing -- Technological innovations , Real estate business -- Data processing , Real estate business -- South Africa -- Technological innovations
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/148380 , vital:38734
- Description: The real estate transaction process has been described as inefficient and technologically outdated due to numerous stakeholders and predominantly paper-based operations. Despite the apparent bottlenecks in the current process, the implementation of new technology into the real estate sector has lagged. Several attempts have been made to modernise and digitise the business process but committed integration of assisting technology has lacked attention. This study examined the applicability and potential integration of blockchain technology into the business process of South African real estate transactions. Blockchain’s novelty means that research in this space, especially within South Africa, is limited. Of the research that has been conducted, no models of the business processes for South African or blockchain-based real estate transactions have been constructed. This study provides two business process models, illustrating the two different processes. The main contribution of this paper was an integrated business process model, illustrating how the various processes and stakeholder interactions for South African blockchain-based real estate transactions are conducted on one transaction platform, common to all participating stakeholders. This platform was named the South African Blockchain Land Exchange System (SABLES), which manages and facilitates these transactions in their entirety from start to finish. This model depicts an enhanced business process that provides increased security, transparency, and speed. These benefits will be realised by those who register, adopt, and transact on the platform. Through in-depth interviews, the integrated business process model was assessed. The findings produced a final and combined thematic map, representing the main themes of the analysed interview data, namely blockchain implementation strategies, business process applicability, information technology assimilation, current transaction context, and PropTech 3.0 success factors. The discussion revealed that the current transaction process lacks technological innovation, which increases pressure on the conveyancing role. It was also revealed that there is not only a need within the industry, but a desire, for newer technologies to assist the transaction process. In order to streamline and improve efficiency, business processes should leverage digital records and data, and strive for a solution beyond digitisation, achieving digitalisation. Digitalisation recognises digital documents as official and legal documents as opposed to simply being digital back-ups. This, coupled with the business process models, represent theoretical contributions.
- Full Text:
- Date Issued: 2020
A career in photophysicochemical and electrochemical properties of phthalocyanine: A Linstead Career Award paper
- Authors: Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186045 , vital:44458 , xlink:href="https://doi.org/10.1142/S1088424620300037"
- Description: This manuscript highlights the author’s contributions to phthalocyanine chemistry, especially the applications based on their electrochemistry and photophysicochemistry. In particular, the use of phthalocyanines as electrocatalysts and photocatalysts is presented. For photocatalysis, photodynamic antimicrobial chemotherapy and pollution control using green technologies are highlighted. For electrocatalysis the phthalocyanines are employed for the detection of pollutants and environmentally important molecules. Phthalocyanines are combined with nanomaterials for improved photocatalysis and electrocatalysis.
- Full Text:
- Date Issued: 2020
- Authors: Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186045 , vital:44458 , xlink:href="https://doi.org/10.1142/S1088424620300037"
- Description: This manuscript highlights the author’s contributions to phthalocyanine chemistry, especially the applications based on their electrochemistry and photophysicochemistry. In particular, the use of phthalocyanines as electrocatalysts and photocatalysts is presented. For photocatalysis, photodynamic antimicrobial chemotherapy and pollution control using green technologies are highlighted. For electrocatalysis the phthalocyanines are employed for the detection of pollutants and environmentally important molecules. Phthalocyanines are combined with nanomaterials for improved photocatalysis and electrocatalysis.
- Full Text:
- Date Issued: 2020
A classification of large wetlands in Africa’s elevated drylands based on their formation, structure, and hydrological functioning using Earth Observation (EO) data and Geographic Information System (GIS)
- Authors: Lidzhegu, Zwidofhelangani
- Date: 2020
- Subjects: Wetlands -- Africa -- Classification , Wetlands -- Africa -- Research , Wetlands -- Africa -- Monitoring , Topographical surveying -- Africa , Hydrological surveys == Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142668 , vital:38100
- Description: Due to wetland inaccessibility and limited wetland geomorphological studies, there is limited information on the geomorphological origin and hydrological functioning of different types of wetlands in Africa’s elevated drylands. As a result, there is limited information for the development of a comprehensive wetland classification system that classifies wetlands based on long-term geomorphic processes that determine their formation and shape, their structure and hydrological functioning. Therefore, the current study was designed to classify large wetlands in Africa’s elevated drylands based on processes that determine their formation, and shape their structure and hydrological functioning using remote sensing and Geographic Information System (GIS) techniques. Although wetlands perform a number of hydrological functions including groundwater recharge and water purification, the current study focuses mainly on their flood attenuation function. Detailed analysis of topographic information was undertaken using Shuttle Radar Topographic Mission (SRTM) elevations measured at the scale of 30 m x 30 m. LandsatLook and Google Earth images, tectonic as well as geological data were used as supplementary data for developing an understanding of the origin, structure and hydrological characteristics of wetlands. The Principal Component Analysis (PCA) of wetland environmental variables was used to identify and explain wetland heterogeneity. The results of the study showed that fluvial processes, tectonic history and the evolution of Africa’s landscape played a fundamental role in the formation and evolution of wetlands. This study demonstrates a wide range of processes that contribute to wetland formation, structure and functioning. At one extreme it is clear that tectonic processes may be primarily responsible for the creation of basins that host wetlands. At another extreme, wetlands may be structured primarily by fluvial processes. At a third extreme are wetlands that superficially appear to be structured by fluvial processes, but which have their structures modified by gradual rising of the base level at their distal ends, either through marginal uplift adjacent to rift valleys, or through aggradation of a floodplain that blocks a tributary valley. Overall, the classification of wetlands considered in this study can be summarised into four distinct groupings, with two of these divided further into two groupings each: (1) Tectonic basins with little or no indication of fluvial development (Bahi and Wembere wetlands), (2) Tectonic basins evolving towards a wetland with a structure increasingly shaped by fluvial characteristics (Usangu wetland), (3) Fluvially modified valleys with a local base level at the toe of the wetland such as a resistant lithology or a tectonic control that limits the rate of incision of easily weathered and eroded lithologies, leading to valley widening and longitudinal slope reduction, which are of two distinct types: (a) With a catchment on Kalahari Group sediment that is transported fluvially as bedload, and therefore with no prominent alluvial ridge or backwater depressions (Upper Zambezi and Barotse wetlands), (b) With a catchment that produces abundant fine sediment that is deposited as overbank sediments, leading to channel migration via meandering and to the construction of an elevated alluvial ridge (Lufira wetland), (4) Fluvially modified basins with evidence of gradual elevation of the base level at the toe of the wetland, which are of two types: (a) Tectonic marginal rift valley uplift such that they behave more as depression wetlands rather than as wetlands shaped by fluvial processes (Kafue and Luapula wetlands), (b) Tributary valley wetlands blocked by aggradation of the trunk valley (Lukanga wetland). In conclusion, although few geomorphological studies have been conducted on southern African wetlands because of their inaccessibility, Africa’s surface topography and its historical evolution, as well as aridity, provide an opportunity for illustrating the important role that the long-term tectonic, geological and geomorphological processes play in determining wetland origin, structure and dynamics. GIS methodology and Earth Observation (EO) data on the other hand, provide a practical means for acquiring information on inaccessible and hard to traverse wetland systems. A novel cut-and-fill approach for delineating wetlands from a Digital Elevation Model (DEM) was presented as another way in which GIS methodology and Earth Observation (EO) data can provide practical means for assessing inaccessible and hard to traverse wetland systems.
- Full Text:
- Date Issued: 2020
- Authors: Lidzhegu, Zwidofhelangani
- Date: 2020
- Subjects: Wetlands -- Africa -- Classification , Wetlands -- Africa -- Research , Wetlands -- Africa -- Monitoring , Topographical surveying -- Africa , Hydrological surveys == Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/142668 , vital:38100
- Description: Due to wetland inaccessibility and limited wetland geomorphological studies, there is limited information on the geomorphological origin and hydrological functioning of different types of wetlands in Africa’s elevated drylands. As a result, there is limited information for the development of a comprehensive wetland classification system that classifies wetlands based on long-term geomorphic processes that determine their formation and shape, their structure and hydrological functioning. Therefore, the current study was designed to classify large wetlands in Africa’s elevated drylands based on processes that determine their formation, and shape their structure and hydrological functioning using remote sensing and Geographic Information System (GIS) techniques. Although wetlands perform a number of hydrological functions including groundwater recharge and water purification, the current study focuses mainly on their flood attenuation function. Detailed analysis of topographic information was undertaken using Shuttle Radar Topographic Mission (SRTM) elevations measured at the scale of 30 m x 30 m. LandsatLook and Google Earth images, tectonic as well as geological data were used as supplementary data for developing an understanding of the origin, structure and hydrological characteristics of wetlands. The Principal Component Analysis (PCA) of wetland environmental variables was used to identify and explain wetland heterogeneity. The results of the study showed that fluvial processes, tectonic history and the evolution of Africa’s landscape played a fundamental role in the formation and evolution of wetlands. This study demonstrates a wide range of processes that contribute to wetland formation, structure and functioning. At one extreme it is clear that tectonic processes may be primarily responsible for the creation of basins that host wetlands. At another extreme, wetlands may be structured primarily by fluvial processes. At a third extreme are wetlands that superficially appear to be structured by fluvial processes, but which have their structures modified by gradual rising of the base level at their distal ends, either through marginal uplift adjacent to rift valleys, or through aggradation of a floodplain that blocks a tributary valley. Overall, the classification of wetlands considered in this study can be summarised into four distinct groupings, with two of these divided further into two groupings each: (1) Tectonic basins with little or no indication of fluvial development (Bahi and Wembere wetlands), (2) Tectonic basins evolving towards a wetland with a structure increasingly shaped by fluvial characteristics (Usangu wetland), (3) Fluvially modified valleys with a local base level at the toe of the wetland such as a resistant lithology or a tectonic control that limits the rate of incision of easily weathered and eroded lithologies, leading to valley widening and longitudinal slope reduction, which are of two distinct types: (a) With a catchment on Kalahari Group sediment that is transported fluvially as bedload, and therefore with no prominent alluvial ridge or backwater depressions (Upper Zambezi and Barotse wetlands), (b) With a catchment that produces abundant fine sediment that is deposited as overbank sediments, leading to channel migration via meandering and to the construction of an elevated alluvial ridge (Lufira wetland), (4) Fluvially modified basins with evidence of gradual elevation of the base level at the toe of the wetland, which are of two types: (a) Tectonic marginal rift valley uplift such that they behave more as depression wetlands rather than as wetlands shaped by fluvial processes (Kafue and Luapula wetlands), (b) Tributary valley wetlands blocked by aggradation of the trunk valley (Lukanga wetland). In conclusion, although few geomorphological studies have been conducted on southern African wetlands because of their inaccessibility, Africa’s surface topography and its historical evolution, as well as aridity, provide an opportunity for illustrating the important role that the long-term tectonic, geological and geomorphological processes play in determining wetland origin, structure and dynamics. GIS methodology and Earth Observation (EO) data on the other hand, provide a practical means for acquiring information on inaccessible and hard to traverse wetland systems. A novel cut-and-fill approach for delineating wetlands from a Digital Elevation Model (DEM) was presented as another way in which GIS methodology and Earth Observation (EO) data can provide practical means for assessing inaccessible and hard to traverse wetland systems.
- Full Text:
- Date Issued: 2020
A cloud adoption framework for South African SMEs
- Authors: Mudzamba, Ronald Ratidzo
- Date: 2020
- Subjects: Cloud computing , Cloud computing -- Security measures , Small business -- Technological innovations -- South Africa -- Eastern Cape , Small business -- Information technology -- South Africa -- Eastern Cape , Information technology -- South Africa -- Eastern Cape , Technology-Organisation-Environment (TOE) framework , Small to Medium Enterprises (SMEs)
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/148574 , vital:38751
- Description: Small to Medium Enterprises (SMEs) have been touted as key enablers to the economic development of most countries. Despite growing evidence that most SMEs fail within their initial years, ICTs have been found to add substantial value in facilitating their success. However, in most developing countries, ICT adoption by SMEs has been plagued with a plethora of challenges ranging from poor electricity supply, high ICT costs, lack of ICT expertise to lack of government support. While this might seem problematic for SMEs, the adoption and the use of cloud services mitigates some of these challenges. The problem, however, is that a limited amount of literature has provided guidance with regard to how the cloud adoption process should be carried out by SMEs. The objective of this research, was therefore, to address this by developing a framework that can be used by SMEs to guide them through the cloud adoption process. To this end, thirteen (13) semi-structured interviews were conducted across nine (9) SMEs in the Eastern Cape. The resultant interview transcripts were analysed using an established thematic approach; the result of which allowed for the development of a rich interpretive narrative about SME cloud adoption. Combined with theory from extant literature, this culminated in the development of a framework for cloud services adoption for SMEs in the Eastern Cape.
- Full Text:
- Date Issued: 2020
- Authors: Mudzamba, Ronald Ratidzo
- Date: 2020
- Subjects: Cloud computing , Cloud computing -- Security measures , Small business -- Technological innovations -- South Africa -- Eastern Cape , Small business -- Information technology -- South Africa -- Eastern Cape , Information technology -- South Africa -- Eastern Cape , Technology-Organisation-Environment (TOE) framework , Small to Medium Enterprises (SMEs)
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/148574 , vital:38751
- Description: Small to Medium Enterprises (SMEs) have been touted as key enablers to the economic development of most countries. Despite growing evidence that most SMEs fail within their initial years, ICTs have been found to add substantial value in facilitating their success. However, in most developing countries, ICT adoption by SMEs has been plagued with a plethora of challenges ranging from poor electricity supply, high ICT costs, lack of ICT expertise to lack of government support. While this might seem problematic for SMEs, the adoption and the use of cloud services mitigates some of these challenges. The problem, however, is that a limited amount of literature has provided guidance with regard to how the cloud adoption process should be carried out by SMEs. The objective of this research, was therefore, to address this by developing a framework that can be used by SMEs to guide them through the cloud adoption process. To this end, thirteen (13) semi-structured interviews were conducted across nine (9) SMEs in the Eastern Cape. The resultant interview transcripts were analysed using an established thematic approach; the result of which allowed for the development of a rich interpretive narrative about SME cloud adoption. Combined with theory from extant literature, this culminated in the development of a framework for cloud services adoption for SMEs in the Eastern Cape.
- Full Text:
- Date Issued: 2020
A combined modelling approach for simulating channel–wetland exchanges in large African river basins
- Authors: Makungu, Eunice J
- Date: 2020
- Subjects: Watersheds -- Africa , Watershed management -- Africa , Water resources development -- Africa -- International cooperation , Floodplain management -- Africa , Wetland ecology -- Simulation methods -- Africa , Wetland management -- Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/123288 , vital:35424
- Description: In Africa, many large and extensive wetlands are hydrologically connected to rivers, and their environmental integrity, as well as their influence on downstream flow regimes, depends on the prevailing channel–wetland exchange processes. These processes are inherently complex and vary spatially and temporally. Understanding channel–wetland exchanges is therefore, indispensable for the effective management of wetlands and the associated river basins. However, this information is limited in most of the river basins containing large wetlands in Africa. Furthermore, it is important to understand the links between upstream and downstream flow regimes and the wetland dynamics themselves, specifically where there are water resource developments that may affect these links (upstream developments), or be affected by them (downstream developments). Hydrological modelling of the entire basin using basin-scale models that include wetland components in their structures can be used to provide the information required to manage water resources in such basins. However, the level of detail of wetland processes included in many basin-scale models is typically very low and the lack of understanding of the wetland dynamics makes it difficult to quantify the relevant parameters. Detailed hydraulic models represent the channel-wetland exchanges in a much more explicit manner, but require relatively more data and time resources to establish than coarser scale hydrological models. The main objective of this study was, therefore, to investigate the use of a detailed hydraulic wetland model to provide a better understanding of channel–wetland exchanges and wetland dynamics, and to use the results to improve the parameterisation of a basin-scale model. The study focused on improving the water resource assessments modelling of three data-scarce African river basins that contain large wetlands: the floodplains of the Luangwa and Upper Zambezi River basins and the Usangu wetland in the Upper Great Ruaha River basin. The overall objective was achieved through a combined modelling approach that uses a detailed high-resolution LISFLOOD-FP hydraulic model to inform the structure and parameters of the GW Pitman monthly hydrological model. The results from the LISFLOOD-FP were used to improve the understanding of the channel–wetland exchange dynamics and to establish the wetland parameters required in the GW Pitman model. While some wetland parameters were directly quantified from the LISFLOOD-FP model results, others, which are highly empirical, were estimated by manually calibrating the GW Pitman wetland sub-model implemented in excel spreadsheets containing the LISFLOOD-FP model results. Finally, the GW Pitman model with the inclusion of the estimated wetland parameters was applied for each basin and the results compared to the available downstream observed flow data. The two models have been successfully applied in southern Africa, with the GW Pitman model being one of the most widely applied hydrological models in this region. To address the issue of data scarcity, during setup of these models, the study mainly relied on the global datasets which clearly adds to the overall uncertainty of the modelling approach. However, this is a typical situation for most of the data scarce regions of the continent. A number of challenges were, however, faced during the setup of the LISFLOOD-FP, mainly due to the limitations of the data inputs. Some of the LISFLOOD-FP data inputs include boundary conditions (upstream and downstream), channel cross-sections and wetland topography. In the absence of observed daily flows to quantify the wetland upstream boundary conditions, monthly flow volumes simulated using the GW Pitman monthly model (without including the wetland sub-model) were disaggregated into daily flows using a disaggregation sub-model. The simulated wetland inflows were evaluated using the observed flow data for downstream gauging stations that include the wetland effects. The results highlighted that it is important to understand the possible impacts of each wetland on the downstream flow regime during the evaluations of the model simulation results. Although the disaggregation approach cannot be validated due to a lack of observed data, it at least enables the simulated monthly flows to be used in the daily time step hydraulic model. One of the recommendations is that improvements are required in gauging station networks to provide more observed information for the main river and the larger tributary inflows into these large and important wetland systems. Even a limited amount of newly observed data would be helpful to reduce some of the uncertainties in the combined modelling approach. The SRTM 90 m DEM (used to represent wetland topography) was filtered to reduce local variations and noise effects (mainly vegetation bias), but there were some pixels that falsely affect the inundation results, and the recently released vegetation-corrected DEMs are suggested to improve the simulation results. Channel cross-section values derived from global datasets should be examined because some widths estimated from the Andreadis et al. (2013) dataset were found to be over-generalised and did not reflect widths measured using high-resolution Google Earth in many places. There is an indication that channel cross-sections digitised from Google Earth images can be successfully used in the model setup except in densely vegetated swamps where the values are difficult to estimate, and in such situations, field measured cross-section data are required. Small channels such as those found in the Usangu wetland could play major role in the exchange dynamics, but digitising them all was not straightforward and only key ones were included in the model setup. Clearly, this inevitably introduced uncertainties in the simulated results, and future studies should consider applying methods that simplify extractions of most of these channels from high-resolution images to improve the simulated results. The study demonstrated that the wetland and channel physical characteristics, as well as the seasonal flow magnitude, largely influence the channel–wetland exchanges and wetland dynamics. The inundation results indicated that the area–storage and storage–inflow relationships form hysteretic curves, but the shape of these curves vary with flood magnitude and wetland type. Anticlockwise hysteresis curves were observed in both relationships for the floodplains (Luangwa and Barotse), whereas there appears to be no dominant curve type for the Usangu wetlands. The lack of well-defined hysteretic relationships in the Usangu could be related to some of the difficulties (and resulting uncertainties) that were experienced in setting up the model for this wetland. The storage–inflow relationships in all wetlands have quite complex rising limbs due to multiple flow peaks during the main wet season. The largest inundation area and storage volume for the Barotse and Usangu wetlands occurred after the peak discharge of the wet season, a result that is clearly related to the degree of connectivity between the main channel and those areas of the wetlands that are furthest away from the channel. Hysteresis effects were found to increase with an increase in flood magnitudes and temporal variations in the wetland inflows. Overall, hysteresis behaviour is common in large wetlands and it is recommended that hysteresis curves should be reflected in basin-scale modelling of large river basins with substantial wetland areas. At a daily time scale, inflow–outflow relationships showed a significant peak reduction and a delayed time to peak of several weeks in the Barotse and Usangu wetlands, whereas the attenuation effects of the Luangwa floodplain are minimal. To a large extent, the LISFLOOD-FP results provided useful information to establish wetland parameters and assess the structure of Pitman wetland sub-model. The simple spreadsheet used to estimate wetland parameters did not account for the wetland water transfers from the upstream to the next section downstream (the condition that is included in the LISFLOOD-FP model) for the case when the wetlands were distributed across more than one sub-basin. It is recommended that a method that allows for the upstream wetland inflows and the channel inflows should be included in the spreadsheet. The same is true to the Pitman model structure, and a downstream transfer of water can be modelled through return flows to the channel. The structure of the wetland sub-model was modified to allow an option for the return flows to occur at any time during the simulation period to provide for types of wetlands (e.g. the Luangwa) where spills from the channel and drainage back to the channel occur simultaneously. The setup of the GW Pitman model with the inclusion of wetland parameters improved the simulation results. However, the results for the Usangu wetlands were not very satisfactory and the collection of additional field data related to exchange dynamics is recommended to achieve improvements. The impacts of the Luangwa floodplain on the flow regime of the Luangwa River are very small at the monthly time scale, whereas the Barotse floodplain system and the Usangu wetlands extensively regulate flows of the Zambezi River and the Great Ruaha River, respectively. The results highlighted the possibilities of regionalising some wetland parameters using an understanding of wetland physical characteristics and their water exchange dynamics. However, some parameters remain difficult to quantify in the absence of site-specific information about the water exchange dynamics. The overall conclusion is that the approach implemented in this study presents an important step towards the improvements of water resource assessments modelling for research and practical purposes in data-scarce river basins. This approach is not restricted to the two used models, as it can be applied using different model combinations to achieve similar study purpose.
- Full Text:
- Date Issued: 2020
A combined modelling approach for simulating channel–wetland exchanges in large African river basins
- Authors: Makungu, Eunice J
- Date: 2020
- Subjects: Watersheds -- Africa , Watershed management -- Africa , Water resources development -- Africa -- International cooperation , Floodplain management -- Africa , Wetland ecology -- Simulation methods -- Africa , Wetland management -- Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/123288 , vital:35424
- Description: In Africa, many large and extensive wetlands are hydrologically connected to rivers, and their environmental integrity, as well as their influence on downstream flow regimes, depends on the prevailing channel–wetland exchange processes. These processes are inherently complex and vary spatially and temporally. Understanding channel–wetland exchanges is therefore, indispensable for the effective management of wetlands and the associated river basins. However, this information is limited in most of the river basins containing large wetlands in Africa. Furthermore, it is important to understand the links between upstream and downstream flow regimes and the wetland dynamics themselves, specifically where there are water resource developments that may affect these links (upstream developments), or be affected by them (downstream developments). Hydrological modelling of the entire basin using basin-scale models that include wetland components in their structures can be used to provide the information required to manage water resources in such basins. However, the level of detail of wetland processes included in many basin-scale models is typically very low and the lack of understanding of the wetland dynamics makes it difficult to quantify the relevant parameters. Detailed hydraulic models represent the channel-wetland exchanges in a much more explicit manner, but require relatively more data and time resources to establish than coarser scale hydrological models. The main objective of this study was, therefore, to investigate the use of a detailed hydraulic wetland model to provide a better understanding of channel–wetland exchanges and wetland dynamics, and to use the results to improve the parameterisation of a basin-scale model. The study focused on improving the water resource assessments modelling of three data-scarce African river basins that contain large wetlands: the floodplains of the Luangwa and Upper Zambezi River basins and the Usangu wetland in the Upper Great Ruaha River basin. The overall objective was achieved through a combined modelling approach that uses a detailed high-resolution LISFLOOD-FP hydraulic model to inform the structure and parameters of the GW Pitman monthly hydrological model. The results from the LISFLOOD-FP were used to improve the understanding of the channel–wetland exchange dynamics and to establish the wetland parameters required in the GW Pitman model. While some wetland parameters were directly quantified from the LISFLOOD-FP model results, others, which are highly empirical, were estimated by manually calibrating the GW Pitman wetland sub-model implemented in excel spreadsheets containing the LISFLOOD-FP model results. Finally, the GW Pitman model with the inclusion of the estimated wetland parameters was applied for each basin and the results compared to the available downstream observed flow data. The two models have been successfully applied in southern Africa, with the GW Pitman model being one of the most widely applied hydrological models in this region. To address the issue of data scarcity, during setup of these models, the study mainly relied on the global datasets which clearly adds to the overall uncertainty of the modelling approach. However, this is a typical situation for most of the data scarce regions of the continent. A number of challenges were, however, faced during the setup of the LISFLOOD-FP, mainly due to the limitations of the data inputs. Some of the LISFLOOD-FP data inputs include boundary conditions (upstream and downstream), channel cross-sections and wetland topography. In the absence of observed daily flows to quantify the wetland upstream boundary conditions, monthly flow volumes simulated using the GW Pitman monthly model (without including the wetland sub-model) were disaggregated into daily flows using a disaggregation sub-model. The simulated wetland inflows were evaluated using the observed flow data for downstream gauging stations that include the wetland effects. The results highlighted that it is important to understand the possible impacts of each wetland on the downstream flow regime during the evaluations of the model simulation results. Although the disaggregation approach cannot be validated due to a lack of observed data, it at least enables the simulated monthly flows to be used in the daily time step hydraulic model. One of the recommendations is that improvements are required in gauging station networks to provide more observed information for the main river and the larger tributary inflows into these large and important wetland systems. Even a limited amount of newly observed data would be helpful to reduce some of the uncertainties in the combined modelling approach. The SRTM 90 m DEM (used to represent wetland topography) was filtered to reduce local variations and noise effects (mainly vegetation bias), but there were some pixels that falsely affect the inundation results, and the recently released vegetation-corrected DEMs are suggested to improve the simulation results. Channel cross-section values derived from global datasets should be examined because some widths estimated from the Andreadis et al. (2013) dataset were found to be over-generalised and did not reflect widths measured using high-resolution Google Earth in many places. There is an indication that channel cross-sections digitised from Google Earth images can be successfully used in the model setup except in densely vegetated swamps where the values are difficult to estimate, and in such situations, field measured cross-section data are required. Small channels such as those found in the Usangu wetland could play major role in the exchange dynamics, but digitising them all was not straightforward and only key ones were included in the model setup. Clearly, this inevitably introduced uncertainties in the simulated results, and future studies should consider applying methods that simplify extractions of most of these channels from high-resolution images to improve the simulated results. The study demonstrated that the wetland and channel physical characteristics, as well as the seasonal flow magnitude, largely influence the channel–wetland exchanges and wetland dynamics. The inundation results indicated that the area–storage and storage–inflow relationships form hysteretic curves, but the shape of these curves vary with flood magnitude and wetland type. Anticlockwise hysteresis curves were observed in both relationships for the floodplains (Luangwa and Barotse), whereas there appears to be no dominant curve type for the Usangu wetlands. The lack of well-defined hysteretic relationships in the Usangu could be related to some of the difficulties (and resulting uncertainties) that were experienced in setting up the model for this wetland. The storage–inflow relationships in all wetlands have quite complex rising limbs due to multiple flow peaks during the main wet season. The largest inundation area and storage volume for the Barotse and Usangu wetlands occurred after the peak discharge of the wet season, a result that is clearly related to the degree of connectivity between the main channel and those areas of the wetlands that are furthest away from the channel. Hysteresis effects were found to increase with an increase in flood magnitudes and temporal variations in the wetland inflows. Overall, hysteresis behaviour is common in large wetlands and it is recommended that hysteresis curves should be reflected in basin-scale modelling of large river basins with substantial wetland areas. At a daily time scale, inflow–outflow relationships showed a significant peak reduction and a delayed time to peak of several weeks in the Barotse and Usangu wetlands, whereas the attenuation effects of the Luangwa floodplain are minimal. To a large extent, the LISFLOOD-FP results provided useful information to establish wetland parameters and assess the structure of Pitman wetland sub-model. The simple spreadsheet used to estimate wetland parameters did not account for the wetland water transfers from the upstream to the next section downstream (the condition that is included in the LISFLOOD-FP model) for the case when the wetlands were distributed across more than one sub-basin. It is recommended that a method that allows for the upstream wetland inflows and the channel inflows should be included in the spreadsheet. The same is true to the Pitman model structure, and a downstream transfer of water can be modelled through return flows to the channel. The structure of the wetland sub-model was modified to allow an option for the return flows to occur at any time during the simulation period to provide for types of wetlands (e.g. the Luangwa) where spills from the channel and drainage back to the channel occur simultaneously. The setup of the GW Pitman model with the inclusion of wetland parameters improved the simulation results. However, the results for the Usangu wetlands were not very satisfactory and the collection of additional field data related to exchange dynamics is recommended to achieve improvements. The impacts of the Luangwa floodplain on the flow regime of the Luangwa River are very small at the monthly time scale, whereas the Barotse floodplain system and the Usangu wetlands extensively regulate flows of the Zambezi River and the Great Ruaha River, respectively. The results highlighted the possibilities of regionalising some wetland parameters using an understanding of wetland physical characteristics and their water exchange dynamics. However, some parameters remain difficult to quantify in the absence of site-specific information about the water exchange dynamics. The overall conclusion is that the approach implemented in this study presents an important step towards the improvements of water resource assessments modelling for research and practical purposes in data-scarce river basins. This approach is not restricted to the two used models, as it can be applied using different model combinations to achieve similar study purpose.
- Full Text:
- Date Issued: 2020
A comparative analysis of social media brand image of insurance companies in South Africa: a longitudinal study
- Authors: Gudu, Daniel
- Date: 2020
- Subjects: Social media -- South Africa , Internet marketing -- South Africa , Chernoff faces , Ínsurance companies -- South Africa -- Marketing , Insurance companies -- South Africa -- Case studies , Multivariate analysis -- Graphic methods
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/144277 , vital:38327
- Description: Social media is changing the way business is conducted. Almost five billion videos are watched on YouTube every single day. Social media has an extensive worldwide presence. Out of the total global population of over 7,5 billion people, over 4 billion are internet users. Of these, over 3 billion are active on social media. Social media is very influential in today's decision-making processes. Businesses must integrate social media into their strategies. The purpose of this research was to investigate the use of a novel method, Chernoff Faces, to assess and compare the social media brand images of six insurance companies in South Africa based on social conversation measurement. The intention of research was towards observing existing situations at hand and pointing out the game changers that can provide the industry with a new leap. Social media are multidimensional and understanding them requires tracking different measures simultaneously. Integrating social media into a communication strategy leads to a problem in finding the best way to portray and communicate multivariate data. It is essential to find the best way to represent and transmit the data so that marketing executives can quickly and easily monitor changes in brand images. Previous studies have successfully proved the possibility of using this method to gauge a "snapshot in time." This study took the concept further by closely monitoring the results for a set of brands over a period to account for the dynamic nature of social media. Accordingly, the study was a longitudinal study of 30 days. Data on the insurance companies was collected from Social Mention, a social media search and analysis platform that aggregates user-generated content into a single stream of information. A tool in the statistical software Stata, Chernoff's faces, was used to analyse the results by generating facial expressions to the metrics associated with the social mentions of each of the insurance companies. The resulting facial expressions were then analysed to recognise the more favourable and stable brands and those that need appropriate risk management. Managing Social Media is challenging as managers must always keep it as positive as possible. Brand managers, therefore, need a better tool to gauge the mood in social media conversations due to the fast-changing nature of social media and the importance of social media to business especially insurance.
- Full Text:
- Date Issued: 2020
- Authors: Gudu, Daniel
- Date: 2020
- Subjects: Social media -- South Africa , Internet marketing -- South Africa , Chernoff faces , Ínsurance companies -- South Africa -- Marketing , Insurance companies -- South Africa -- Case studies , Multivariate analysis -- Graphic methods
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/144277 , vital:38327
- Description: Social media is changing the way business is conducted. Almost five billion videos are watched on YouTube every single day. Social media has an extensive worldwide presence. Out of the total global population of over 7,5 billion people, over 4 billion are internet users. Of these, over 3 billion are active on social media. Social media is very influential in today's decision-making processes. Businesses must integrate social media into their strategies. The purpose of this research was to investigate the use of a novel method, Chernoff Faces, to assess and compare the social media brand images of six insurance companies in South Africa based on social conversation measurement. The intention of research was towards observing existing situations at hand and pointing out the game changers that can provide the industry with a new leap. Social media are multidimensional and understanding them requires tracking different measures simultaneously. Integrating social media into a communication strategy leads to a problem in finding the best way to portray and communicate multivariate data. It is essential to find the best way to represent and transmit the data so that marketing executives can quickly and easily monitor changes in brand images. Previous studies have successfully proved the possibility of using this method to gauge a "snapshot in time." This study took the concept further by closely monitoring the results for a set of brands over a period to account for the dynamic nature of social media. Accordingly, the study was a longitudinal study of 30 days. Data on the insurance companies was collected from Social Mention, a social media search and analysis platform that aggregates user-generated content into a single stream of information. A tool in the statistical software Stata, Chernoff's faces, was used to analyse the results by generating facial expressions to the metrics associated with the social mentions of each of the insurance companies. The resulting facial expressions were then analysed to recognise the more favourable and stable brands and those that need appropriate risk management. Managing Social Media is challenging as managers must always keep it as positive as possible. Brand managers, therefore, need a better tool to gauge the mood in social media conversations due to the fast-changing nature of social media and the importance of social media to business especially insurance.
- Full Text:
- Date Issued: 2020
A comparative analysis of the use of participatory practices by indigenous trusts and mainstream development NGOs in Zvimba Communal Area Zimbabwe
- Authors: Mbanje, Bowden Bolt
- Date: 2020
- Subjects: Caritas Zimbabwe , Zvimba Community Share Ownership Trust (ZvCSOT) , Non-governmental organizations -- Zimbabwe -- Zvimba District , Community development -- Zimbabwe -- Zvimba District , Rural development -- Zimbabwe -- Zvimba District , Zvimba Communal Land (Zimbabwe)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167099 , vital:41437
- Description: This thesis compares the extent to which participatory practices have been used by Caritas Zimbabwe, a mainstream NGO, and the Zvimba Community Share Ownership Trust (ZvCSOT), an indigenous Trust, in Zvimba District, Zimbabwe. Participatory development initiatives are common practice in NGO and government development work in Zimbabwe. The thesis begins with a discussion of two aspects of participatory development (PD). Firstly, PD is discussed in relation to decentralization processes where central government transfers administrative and financial authority to sub-national government units in order to enhance the participation of rural communities in development interventions. Secondly, PD is discussed in relation to the increased role of NGOs in development work. During the 1980s and 1990s, shifts in development thinking resulted in NGOs being perceived as important actors who could attend to the development gaps left by an economically incapacitated state. Both NGOs and sub-national government units were seen to be closer to rural communities and so were thought to be in a better position to enhance the participation of these communities in meaningful development projects. An analysis of the practices of the NGO and CSOT under consideration in this study shows that while there has been much rhetorical commitment to participation, community participation in the development interventions of the NGO and the CSOT is inadequate. In introducing and implementing development interventions, there has been a tendency by both the NGO and CSOT to give priority to organizational preferences over local needs. While recognizing the participatory efforts made by mainstream development NGOs (Caritas in particular) and indigenous Trusts (Zvimba Community Share Ownership Trust in particular) in Zimbabwe, this thesis also considers the impact of other factors on participatory development initiatives. A major observation from the study is that in as much as we expect genuine participatory approaches which include grassroots communities’ inputs from the project’s conceptualization all the way to its evaluation, the challenge is that the elites at the higher level (central government and donor offices) have their own development preferences and interests while the elites at the lower levels (local government and NGO offices) also have their own priorities and needs. Consequently, local communities tend to be confined to implementing development projects foisted on them by elites at the higher level as well as those at the lower level. Worse still, the study shows that elites at the lowest level (community) sometimes hijack or take advantage of the imposed projects. Participation has been stalled by elites at various levels of the participatory development ladder. Thus, unless power imbalances are seriously addressed at all levels, participatory development will remain elusive.
- Full Text:
- Date Issued: 2020
- Authors: Mbanje, Bowden Bolt
- Date: 2020
- Subjects: Caritas Zimbabwe , Zvimba Community Share Ownership Trust (ZvCSOT) , Non-governmental organizations -- Zimbabwe -- Zvimba District , Community development -- Zimbabwe -- Zvimba District , Rural development -- Zimbabwe -- Zvimba District , Zvimba Communal Land (Zimbabwe)
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/167099 , vital:41437
- Description: This thesis compares the extent to which participatory practices have been used by Caritas Zimbabwe, a mainstream NGO, and the Zvimba Community Share Ownership Trust (ZvCSOT), an indigenous Trust, in Zvimba District, Zimbabwe. Participatory development initiatives are common practice in NGO and government development work in Zimbabwe. The thesis begins with a discussion of two aspects of participatory development (PD). Firstly, PD is discussed in relation to decentralization processes where central government transfers administrative and financial authority to sub-national government units in order to enhance the participation of rural communities in development interventions. Secondly, PD is discussed in relation to the increased role of NGOs in development work. During the 1980s and 1990s, shifts in development thinking resulted in NGOs being perceived as important actors who could attend to the development gaps left by an economically incapacitated state. Both NGOs and sub-national government units were seen to be closer to rural communities and so were thought to be in a better position to enhance the participation of these communities in meaningful development projects. An analysis of the practices of the NGO and CSOT under consideration in this study shows that while there has been much rhetorical commitment to participation, community participation in the development interventions of the NGO and the CSOT is inadequate. In introducing and implementing development interventions, there has been a tendency by both the NGO and CSOT to give priority to organizational preferences over local needs. While recognizing the participatory efforts made by mainstream development NGOs (Caritas in particular) and indigenous Trusts (Zvimba Community Share Ownership Trust in particular) in Zimbabwe, this thesis also considers the impact of other factors on participatory development initiatives. A major observation from the study is that in as much as we expect genuine participatory approaches which include grassroots communities’ inputs from the project’s conceptualization all the way to its evaluation, the challenge is that the elites at the higher level (central government and donor offices) have their own development preferences and interests while the elites at the lower levels (local government and NGO offices) also have their own priorities and needs. Consequently, local communities tend to be confined to implementing development projects foisted on them by elites at the higher level as well as those at the lower level. Worse still, the study shows that elites at the lowest level (community) sometimes hijack or take advantage of the imposed projects. Participation has been stalled by elites at various levels of the participatory development ladder. Thus, unless power imbalances are seriously addressed at all levels, participatory development will remain elusive.
- Full Text:
- Date Issued: 2020
A comparative analysis with selected jurisdictions of structural challenges facing the South African office of the tax ombud
- Authors: Mothiba, Boitumelo Charity
- Date: 2020
- Subjects: South Africa. Office of the Tax Ombud , Tax administration and procdure -- South Africa , Taxpayer advocates -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/140360 , vital:37882
- Description: The Office of the Tax Ombud is critical in the protection of South African taxpayers' rights. The office has only been in existence for a little over five years and to ensure that it fulfils the purpose for which it was established, it must be properly structured. This includes that it ought to be independent from any external influence and manipulation. Any such external influence on the Tax Ombud creates the risk that the general public will lose confidence in the Tax Ombud as an independent recourse. The study, therefore, is designed to review the structure relating to the independence and powers of the South African Tax Ombud. The study assesses and evaluates the legislative safeguards of the structure of the Tax Ombud office in order to determine whether the legislative framework (the Tax Administration Act) safeguarding the Office of the Tax Ombud is adequate to ensure its independence and also to ensure a strengthened structure, without interference in the decision-making process of the office. To achieve this, a comparative analysis was made with selected foreign institutions of Tax Ombudsmen, or equivalent institutions, in order to draw from the best international practice. The study found that the structure of the Office of the Tax Ombud is relatively weak and does not fully provide the legislative powers to protect taxpayers from the well-resourced South African Revenue Service. The study also revealed that most of the institutional features in the structure of the South African Tax Ombud were found to be in line with standard international practice. The study has made recommendations aimed at strengthening the structure of the South African Tax Ombud by suggesting reforms in the legislative framework of the Tax Ombud.
- Full Text:
- Date Issued: 2020
- Authors: Mothiba, Boitumelo Charity
- Date: 2020
- Subjects: South Africa. Office of the Tax Ombud , Tax administration and procdure -- South Africa , Taxpayer advocates -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/140360 , vital:37882
- Description: The Office of the Tax Ombud is critical in the protection of South African taxpayers' rights. The office has only been in existence for a little over five years and to ensure that it fulfils the purpose for which it was established, it must be properly structured. This includes that it ought to be independent from any external influence and manipulation. Any such external influence on the Tax Ombud creates the risk that the general public will lose confidence in the Tax Ombud as an independent recourse. The study, therefore, is designed to review the structure relating to the independence and powers of the South African Tax Ombud. The study assesses and evaluates the legislative safeguards of the structure of the Tax Ombud office in order to determine whether the legislative framework (the Tax Administration Act) safeguarding the Office of the Tax Ombud is adequate to ensure its independence and also to ensure a strengthened structure, without interference in the decision-making process of the office. To achieve this, a comparative analysis was made with selected foreign institutions of Tax Ombudsmen, or equivalent institutions, in order to draw from the best international practice. The study found that the structure of the Office of the Tax Ombud is relatively weak and does not fully provide the legislative powers to protect taxpayers from the well-resourced South African Revenue Service. The study also revealed that most of the institutional features in the structure of the South African Tax Ombud were found to be in line with standard international practice. The study has made recommendations aimed at strengthening the structure of the South African Tax Ombud by suggesting reforms in the legislative framework of the Tax Ombud.
- Full Text:
- Date Issued: 2020
A comparative study of the effect of different stabilizers on the critical quality attributes of self-assembling nano co-crystals
- Witika, Bwalya A, Smith, Vincent J, Walker, Roderick B
- Authors: Witika, Bwalya A , Smith, Vincent J , Walker, Roderick B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183224 , vital:43931 , xlink:href=" https://doi.org/10.3390/pharmaceutics12020182"
- Description: Lamivudine (3TC) and zidovudine (AZT) are antiviral agents used orally to manage HIV/AIDS infection. A pseudo one-solvent bottom-up approach was used to develop and produce nano co-crystals of 3TC and AZT. Equimolar amounts of 3TC dissolved in de-ionized water and AZT in methanol were rapidly injected into a pre-cooled vessel and sonicated at 4 °C. The resultant suspensions were characterized using a Zetasizer. The particle size, polydispersity index and Zeta potential were elucidated. Further characterization was undertaken using powder X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and energy dispersive X-ray spectroscopy scanning electron microscopy. Different surfactants were assessed for their ability to stabilize the nano co-crystals and for their ability to produce nano co-crystals with specific and desirable critical quality attributes (CQA) including particle size (PS) less than 1000 nm, polydispersity index (PDI) less than 0.500 and Zeta potential (ZP) less than −30 mV. All surfactants produced co-crystals in the nanometer range. The PDI and PS are concentration-dependent for all nano co-crystals manufactured while only ZP was within specification when sodium dodecyl sulfate was used in the process.
- Full Text:
- Date Issued: 2020
- Authors: Witika, Bwalya A , Smith, Vincent J , Walker, Roderick B
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/183224 , vital:43931 , xlink:href=" https://doi.org/10.3390/pharmaceutics12020182"
- Description: Lamivudine (3TC) and zidovudine (AZT) are antiviral agents used orally to manage HIV/AIDS infection. A pseudo one-solvent bottom-up approach was used to develop and produce nano co-crystals of 3TC and AZT. Equimolar amounts of 3TC dissolved in de-ionized water and AZT in methanol were rapidly injected into a pre-cooled vessel and sonicated at 4 °C. The resultant suspensions were characterized using a Zetasizer. The particle size, polydispersity index and Zeta potential were elucidated. Further characterization was undertaken using powder X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, and energy dispersive X-ray spectroscopy scanning electron microscopy. Different surfactants were assessed for their ability to stabilize the nano co-crystals and for their ability to produce nano co-crystals with specific and desirable critical quality attributes (CQA) including particle size (PS) less than 1000 nm, polydispersity index (PDI) less than 0.500 and Zeta potential (ZP) less than −30 mV. All surfactants produced co-crystals in the nanometer range. The PDI and PS are concentration-dependent for all nano co-crystals manufactured while only ZP was within specification when sodium dodecyl sulfate was used in the process.
- Full Text:
- Date Issued: 2020
A comparative study of the photophysicochemical and photodynamic activity properties of meso-4-methylthiophenyl functionalized Sn (IV) tetraarylporphyrins and triarylcorroles
- Dingiswayo, Somila, Babu, Balaji, Prinsloo, Earl, Mack, John, Nyokong, Tebello
- Authors: Dingiswayo, Somila , Babu, Balaji , Prinsloo, Earl , Mack, John , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186157 , vital:44469 , xlink:href="https://doi.org/10.1142/S1088424620500273"
- Description: Tin(IV) complexes of a 4-methylthiophenyl functionalized porphyrin (1-Sn) and its corrole analogue (2-Sn) were synthesized so that their photophysicochemical properties and photodynamic activities against MCF-7 breast cancer cells could be compared. Singlet oxygen luminescence studies revealed that 1-Sn and 2-Sn have comparable ΦΔΦΔ values in DMF of 0.59 and 0.60, respectively, while the IC5050 values after irradiation of MCF-7 cells for 30 min with a Thorlabs 625 nm LED (432 J · cm−2)−2) were determined to be 12.4 and 8.9 μμM. The results demonstrate that the cellular uptake of 2-Sn and its molar absorptivity at the irradiation wavelength play a crucial role during in vitro cytotoxicity studies.
- Full Text:
- Date Issued: 2020
- Authors: Dingiswayo, Somila , Babu, Balaji , Prinsloo, Earl , Mack, John , Nyokong, Tebello
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/186157 , vital:44469 , xlink:href="https://doi.org/10.1142/S1088424620500273"
- Description: Tin(IV) complexes of a 4-methylthiophenyl functionalized porphyrin (1-Sn) and its corrole analogue (2-Sn) were synthesized so that their photophysicochemical properties and photodynamic activities against MCF-7 breast cancer cells could be compared. Singlet oxygen luminescence studies revealed that 1-Sn and 2-Sn have comparable ΦΔΦΔ values in DMF of 0.59 and 0.60, respectively, while the IC5050 values after irradiation of MCF-7 cells for 30 min with a Thorlabs 625 nm LED (432 J · cm−2)−2) were determined to be 12.4 and 8.9 μμM. The results demonstrate that the cellular uptake of 2-Sn and its molar absorptivity at the irradiation wavelength play a crucial role during in vitro cytotoxicity studies.
- Full Text:
- Date Issued: 2020
A comparative study of the tax measures for persons with disabilities in South Africa with those of Canada and the Republic of Ireland
- Authors: Currie, Natasha
- Date: 2020
- Subjects: People with disabilities -- Taxation -- South Africa , People with disabilities -- Taxation -- Law and legislation -- South Africa , People with disabilities -- Taxation -- Canada , People with disabilities -- Taxation -- Law and legislation -- Ireland , People with disabilities -- Taxation -- Ireland
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/170746 , vital:41956
- Description: Literature indicates that tax relief measures for persons with disabilities are important as they align with the principle of equity in the allocation of the tax burden. They are a government intervention that assists in decreasing the financial burden of medical care for persons with disabilities. The right of persons with disabilities to an adequate standard of living is contained in the landmark Convention on the Rights of Persons with Disabilities and Optional Protocol, a treaty of the United Nations, which South Africa ratified in 2007. The objective of the research was to provide a comparative study of tax relief measures for persons with disabilities in South Africa with those of Canada and the Republic of Ireland, with a view to identifying potential areas for improvement in South Africa. The requisite information was primarily collected through an extensive analysis of the tax legislation in the jurisdictions. The research found that tax relief measures for persons with disabilities and their families in South Africa are limited when compared with those of Canada and the Republic of Ireland. The comparative study identifies a number of potential tax relief measures for implementation in South Africa.
- Full Text:
- Date Issued: 2020
- Authors: Currie, Natasha
- Date: 2020
- Subjects: People with disabilities -- Taxation -- South Africa , People with disabilities -- Taxation -- Law and legislation -- South Africa , People with disabilities -- Taxation -- Canada , People with disabilities -- Taxation -- Law and legislation -- Ireland , People with disabilities -- Taxation -- Ireland
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/170746 , vital:41956
- Description: Literature indicates that tax relief measures for persons with disabilities are important as they align with the principle of equity in the allocation of the tax burden. They are a government intervention that assists in decreasing the financial burden of medical care for persons with disabilities. The right of persons with disabilities to an adequate standard of living is contained in the landmark Convention on the Rights of Persons with Disabilities and Optional Protocol, a treaty of the United Nations, which South Africa ratified in 2007. The objective of the research was to provide a comparative study of tax relief measures for persons with disabilities in South Africa with those of Canada and the Republic of Ireland, with a view to identifying potential areas for improvement in South Africa. The requisite information was primarily collected through an extensive analysis of the tax legislation in the jurisdictions. The research found that tax relief measures for persons with disabilities and their families in South Africa are limited when compared with those of Canada and the Republic of Ireland. The comparative study identifies a number of potential tax relief measures for implementation in South Africa.
- Full Text:
- Date Issued: 2020
A comparison between the responsiveness of selected physiological and subjective mental workload indicators during real-world driving scenarios
- Authors: Schmidtke, Nadia-Jasmine
- Date: 2020
- Subjects: Automobile driving -- Physiological aspects , Automobile driving -- Psychological aspects , Automobile drivers -- Health and hygiene , Mental fatigue , Mental work -- Case studies
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/148115 , vital:38711
- Description: Sub-optimal levels of mental workload in automobile drivers is a risk factor for road accidents. However, mental workload as a construct cannot be directly measured. Common indicators of mental workload include heart rate frequency and variability, eye motion and subjective rating tools. Namely, the National Aeronautics and Space Administration Task Load Index (NASA-TLX), its modified, unweighted version called the Raw-TLX, and the Rating Scale of Mental Effort (RSME). Comparisons between the suitability and responsiveness of these mental workload indicators have been almost exclusively examined in driving simulators. However, real-world driving research is important as even high-fidelity simulators cannot capture the complexity of driving scenarios. Hence, this research aimed to compare the suitability and responsiveness of these mental workload indicators in response to real-world driving scenarios. Six participants drove along a set route for an hour while wearing a heart rate monitor and eye tracker. A dashcam was used to capture footage of the different driving scenarios encountered. The set route comprised of driving through the industrial, residential, provincial main road and Rhodes University campus areas. RSME scores were taken during brief stops after driving though each zone. The NASA-TLX questionnaire was administered on completion of the drive and analysed later as the modified Raw-TLX version. The data collected in response to the encountered driving scenarios were sorted into three meta-groupings. (1) Data was segmented according to the different areas that participants drove through. This was termed Area Events and were long duration scenarios of between five and thirty minutes. These driving scenarios were further segmented into two meta-groups with short duration driving scenarios (< 90 seconds). (2) The Common Events meta-group consisted of driving scenarios that were encountered by all participants. These were scenarios were anticipated by drivers. (3) The All Events meta-group was grouped according to all the driving scenarios that were encountered by participants. It consisted of both anticipated and unanticipated driving scenarios of short durations. Data were further analysed using a method of systematically selecting a threshold value for each mental workload indicator. Responses to driving scenarios which surpassed the threshold were considered indicative of an increase in mental workload. The total frequency of higher mental workload events was used as a determiner responsiveness (or ‘sensitivity’) for each mental workload indicator. Mental workload indicators were evaluated for their responsiveness and suitability for assessing mental workload. Results found blink frequency to be a responsive mental workload indicator for all categories of driving scenarios. Blink frequency and duration were the most responsive short duration mental workload indicators. Furthermore, the indicators were able to distinguish between higher and lower mental workload driving scenarios. However, blink parameters are also sensitive to driver fatigue and drowsiness. Further research on distinguishing mental workload from that of fatigue in response to real-world driving was recommended. Pupil diameter, fixation duration, saccade saccade duration and saccade amplitude were found to be responsive short duration mental workload indicators. However, these measures were not determined to be suitable for real-world driving applications. Pupil diameter was confounded by changing illumination levels. Fixation and saccade responses were confounded by the driving task itself as gaze could not be accounted for. For long duration driving scenarios heart rate frequency, heart rate variability: high-frequency power, blink frequency and RSME were found to be responsive and suitable MWL indicators. The Raw-TLX results could not be assessed for responsiveness as it was administered once. However, it was confirmed as a suitable cumulative mental workload indicator in the application of real-world driving. The moderate levels of workload reported by participants agreed with the experimental protocol that prevented inducing sub-optimal mental workload. Blink frequency shows promise as a responsive and suitable mental workload indicator for different types of driving scenarios. More research is needed regarding the assessment of mental workload during short durations using blink frequency and blink duration. For driving durations between five and thirty minutes long, further research into heart rate frequency, heart rate variability: high frequency power, and the RSME was recommended.
- Full Text:
- Date Issued: 2020
- Authors: Schmidtke, Nadia-Jasmine
- Date: 2020
- Subjects: Automobile driving -- Physiological aspects , Automobile driving -- Psychological aspects , Automobile drivers -- Health and hygiene , Mental fatigue , Mental work -- Case studies
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/148115 , vital:38711
- Description: Sub-optimal levels of mental workload in automobile drivers is a risk factor for road accidents. However, mental workload as a construct cannot be directly measured. Common indicators of mental workload include heart rate frequency and variability, eye motion and subjective rating tools. Namely, the National Aeronautics and Space Administration Task Load Index (NASA-TLX), its modified, unweighted version called the Raw-TLX, and the Rating Scale of Mental Effort (RSME). Comparisons between the suitability and responsiveness of these mental workload indicators have been almost exclusively examined in driving simulators. However, real-world driving research is important as even high-fidelity simulators cannot capture the complexity of driving scenarios. Hence, this research aimed to compare the suitability and responsiveness of these mental workload indicators in response to real-world driving scenarios. Six participants drove along a set route for an hour while wearing a heart rate monitor and eye tracker. A dashcam was used to capture footage of the different driving scenarios encountered. The set route comprised of driving through the industrial, residential, provincial main road and Rhodes University campus areas. RSME scores were taken during brief stops after driving though each zone. The NASA-TLX questionnaire was administered on completion of the drive and analysed later as the modified Raw-TLX version. The data collected in response to the encountered driving scenarios were sorted into three meta-groupings. (1) Data was segmented according to the different areas that participants drove through. This was termed Area Events and were long duration scenarios of between five and thirty minutes. These driving scenarios were further segmented into two meta-groups with short duration driving scenarios (< 90 seconds). (2) The Common Events meta-group consisted of driving scenarios that were encountered by all participants. These were scenarios were anticipated by drivers. (3) The All Events meta-group was grouped according to all the driving scenarios that were encountered by participants. It consisted of both anticipated and unanticipated driving scenarios of short durations. Data were further analysed using a method of systematically selecting a threshold value for each mental workload indicator. Responses to driving scenarios which surpassed the threshold were considered indicative of an increase in mental workload. The total frequency of higher mental workload events was used as a determiner responsiveness (or ‘sensitivity’) for each mental workload indicator. Mental workload indicators were evaluated for their responsiveness and suitability for assessing mental workload. Results found blink frequency to be a responsive mental workload indicator for all categories of driving scenarios. Blink frequency and duration were the most responsive short duration mental workload indicators. Furthermore, the indicators were able to distinguish between higher and lower mental workload driving scenarios. However, blink parameters are also sensitive to driver fatigue and drowsiness. Further research on distinguishing mental workload from that of fatigue in response to real-world driving was recommended. Pupil diameter, fixation duration, saccade saccade duration and saccade amplitude were found to be responsive short duration mental workload indicators. However, these measures were not determined to be suitable for real-world driving applications. Pupil diameter was confounded by changing illumination levels. Fixation and saccade responses were confounded by the driving task itself as gaze could not be accounted for. For long duration driving scenarios heart rate frequency, heart rate variability: high-frequency power, blink frequency and RSME were found to be responsive and suitable MWL indicators. The Raw-TLX results could not be assessed for responsiveness as it was administered once. However, it was confirmed as a suitable cumulative mental workload indicator in the application of real-world driving. The moderate levels of workload reported by participants agreed with the experimental protocol that prevented inducing sub-optimal mental workload. Blink frequency shows promise as a responsive and suitable mental workload indicator for different types of driving scenarios. More research is needed regarding the assessment of mental workload during short durations using blink frequency and blink duration. For driving durations between five and thirty minutes long, further research into heart rate frequency, heart rate variability: high frequency power, and the RSME was recommended.
- Full Text:
- Date Issued: 2020
A comparison of representations of the imperative of higher education change as „transformation‟ versus „decolonisation‟ in South African public discourse
- Authors: Makgakge, Rebecca Dineo
- Date: 2020
- Subjects: Education in mass media -- South Africa , Higher education and state -- South Africa , Education, Higher -- Curricula -- South Africa , Discrimination in education -- South Africa , South Africa -- Colonial influence , Educational change -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/142498 , vital:38085
- Description: The context of higher education in South Africa which has been shaped by the legacies of the old apartheid system is faced with a paramount task of the continuous process of restructuring and change. In shaping the restructuring and change of the higher education system the concept of transformation has been a constant theme for the post-apartheid government policies. However more recently we have seen the heightened prominence of the concept of change understood as decolonisation of South African higher education – as opposed to “transformation‘. This thesis was concerned with how these concepts of change, “transformation‘ and “decolonisation‘ have been used in debates surrounding higher education in South Africa. The thesis compares and contrasts the ways and context in which they are used. This study of 177 South African newspaper articles taken form independent media stables from the time 2008 to the present provides an analysis of representations of higher education change as “transformation‘ and as “decolonisation‘ evinced in the corpus. This required using both content and framing analysis as a method to analyse the corpus. Three themes emerged from the analysis that are relevant to the comparison between South African higher education institutional change represented as “transformation‘ and South African higher education institutional change represented at “decolonisation‘: the first theme concerns the differences and similarities in how the two terms are defined; the second theme concerns how the two ideas play themselves out when it comes to curriculum change and the final theme concerns the implications of seeing change as “transformation‘ and seeing change as “decolonisation‘ for changing institutional cultures.
- Full Text:
- Date Issued: 2020
- Authors: Makgakge, Rebecca Dineo
- Date: 2020
- Subjects: Education in mass media -- South Africa , Higher education and state -- South Africa , Education, Higher -- Curricula -- South Africa , Discrimination in education -- South Africa , South Africa -- Colonial influence , Educational change -- South Africa
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/142498 , vital:38085
- Description: The context of higher education in South Africa which has been shaped by the legacies of the old apartheid system is faced with a paramount task of the continuous process of restructuring and change. In shaping the restructuring and change of the higher education system the concept of transformation has been a constant theme for the post-apartheid government policies. However more recently we have seen the heightened prominence of the concept of change understood as decolonisation of South African higher education – as opposed to “transformation‘. This thesis was concerned with how these concepts of change, “transformation‘ and “decolonisation‘ have been used in debates surrounding higher education in South Africa. The thesis compares and contrasts the ways and context in which they are used. This study of 177 South African newspaper articles taken form independent media stables from the time 2008 to the present provides an analysis of representations of higher education change as “transformation‘ and as “decolonisation‘ evinced in the corpus. This required using both content and framing analysis as a method to analyse the corpus. Three themes emerged from the analysis that are relevant to the comparison between South African higher education institutional change represented as “transformation‘ and South African higher education institutional change represented at “decolonisation‘: the first theme concerns the differences and similarities in how the two terms are defined; the second theme concerns how the two ideas play themselves out when it comes to curriculum change and the final theme concerns the implications of seeing change as “transformation‘ and seeing change as “decolonisation‘ for changing institutional cultures.
- Full Text:
- Date Issued: 2020
A comparison of three models used to determine water fluxes over the Albany Thicket, Eastern Cape, South Africa:
- Palmer, Anthony R, Ezenne, G I, Choruma, D J, Gwate, O, Mantel, Sukhmani K, Tanner, Jane L
- Authors: Palmer, Anthony R , Ezenne, G I , Choruma, D J , Gwate, O , Mantel, Sukhmani K , Tanner, Jane L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150047 , vital:38934 , https://doi.org/10.1016/j.agrformet.2020.107984
- Description: The Albany Thicket (AT) biome contains outstanding global biodiversity as well as the potential to achieve carbon credits associated with water-efficient Crasslucean acid metabolism (CAM). Understanding the water fluxes in the AT is crucial to determining carbon (C) sequestration rates and water-use efficiency. Despite large variation in water fluxes across the AT, only a few studies have been conducted in this region with their results validated against short periods of observed data. This study aims to evaluate three models of water fluxes over AT against data from an eddy covariance (EC) system active from October 2015 to May 2018. ET was modelled using the BioGeoChemistry Management (BGC-MAN) model, a biophysical model (Penman-Monteith-Leuning (PML)) and a remotely-sensed product (MOD16), and their results compared with that from the EC system.
- Full Text:
- Date Issued: 2020
- Authors: Palmer, Anthony R , Ezenne, G I , Choruma, D J , Gwate, O , Mantel, Sukhmani K , Tanner, Jane L
- Date: 2020
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150047 , vital:38934 , https://doi.org/10.1016/j.agrformet.2020.107984
- Description: The Albany Thicket (AT) biome contains outstanding global biodiversity as well as the potential to achieve carbon credits associated with water-efficient Crasslucean acid metabolism (CAM). Understanding the water fluxes in the AT is crucial to determining carbon (C) sequestration rates and water-use efficiency. Despite large variation in water fluxes across the AT, only a few studies have been conducted in this region with their results validated against short periods of observed data. This study aims to evaluate three models of water fluxes over AT against data from an eddy covariance (EC) system active from October 2015 to May 2018. ET was modelled using the BioGeoChemistry Management (BGC-MAN) model, a biophysical model (Penman-Monteith-Leuning (PML)) and a remotely-sensed product (MOD16), and their results compared with that from the EC system.
- Full Text:
- Date Issued: 2020
A critical analysis of NGOs in addressing HIV and AIDS in the context of gendered inequality: The case of Makhanda, Eastern Cape, South Africa
- Authors: Mhavika, Moreblessing
- Date: 2020
- Subjects: AIDS (Disease) -- Sex factors , AIDS (Disease) -- Social aspects -- South Africa -- Makhanda , HIV infections -- Sex factors , HIV infections -- Social aspects -- South Africa -- Makhanda , HIV-positive women -- South Africa -- Makhanda , Non-governmental organizations -- South Africa -- Makhanda
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: http://hdl.handle.net/10962/143225 , vital:38212
- Description: South Africa has the highest number of people living with HIV and AIDS in the world. The HIV pandemic has, and continues to have, negative implications for communities and individuals, especially women, in South Africa and beyond. HIV and AIDS has left women disproportionately more infected and affected than men because of social, cultural and economic factors, leading to the feminisation of HIV. South African NGOs have tried to fill in the gap and to respond to the HIV pandemic, either independently or in partnership with government departments. In this context, the purpose of this thesis is to provide a critical analysis of NGO programmes in Makhanda (in the Eastern Cape Province) to ascertain whether NGOs address the feminisation of HIV and, if so, how. In doing so, the study utilises qualitative analysis with the use of interviews, a focus group discussion and primary documents as research methods. The study concludes that local government in Makhanda has failed to address women’s vulnerabilities to HIV and that it does not provide a sufficiently enabling environment for NGOs in this regard. In addition, inadequate funding from donors, alongside issues of accountability and the failure to engage in HIV programmes from a perspective founded in feminism, were factors found to contribute to NGOs not fully considering women’s vulnerabilities to HIV. Resultantly, NGOs in Makhanda rarely, at least intentionally, address the feminisation of HIV.
- Full Text:
- Date Issued: 2020
- Authors: Mhavika, Moreblessing
- Date: 2020
- Subjects: AIDS (Disease) -- Sex factors , AIDS (Disease) -- Social aspects -- South Africa -- Makhanda , HIV infections -- Sex factors , HIV infections -- Social aspects -- South Africa -- Makhanda , HIV-positive women -- South Africa -- Makhanda , Non-governmental organizations -- South Africa -- Makhanda
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: http://hdl.handle.net/10962/143225 , vital:38212
- Description: South Africa has the highest number of people living with HIV and AIDS in the world. The HIV pandemic has, and continues to have, negative implications for communities and individuals, especially women, in South Africa and beyond. HIV and AIDS has left women disproportionately more infected and affected than men because of social, cultural and economic factors, leading to the feminisation of HIV. South African NGOs have tried to fill in the gap and to respond to the HIV pandemic, either independently or in partnership with government departments. In this context, the purpose of this thesis is to provide a critical analysis of NGO programmes in Makhanda (in the Eastern Cape Province) to ascertain whether NGOs address the feminisation of HIV and, if so, how. In doing so, the study utilises qualitative analysis with the use of interviews, a focus group discussion and primary documents as research methods. The study concludes that local government in Makhanda has failed to address women’s vulnerabilities to HIV and that it does not provide a sufficiently enabling environment for NGOs in this regard. In addition, inadequate funding from donors, alongside issues of accountability and the failure to engage in HIV programmes from a perspective founded in feminism, were factors found to contribute to NGOs not fully considering women’s vulnerabilities to HIV. Resultantly, NGOs in Makhanda rarely, at least intentionally, address the feminisation of HIV.
- Full Text:
- Date Issued: 2020
A critical analysis of social enterprise in Slovenia
- Authors: Malila, Brett
- Date: 2020
- Subjects: Social entrepreneurship -- Slovenia , Social entrepreneurship -- Slovenia -- Case studies , Social entrepreneurship -- Law and legilstion-- Slovenia , Business enterprises -- Law and legilstion-- Slovenia
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/166436 , vital:41364
- Description: This research presents a case study on the nature of social enterprise in Slovenia. From a resource-based view (RBV), the case study has been used to show what some of the intangible resources are that can be used to promote sustainable social enterprise (SE). The purpose of this research study is to analyse social enterprises in Slovenia in order to establish a framework which other social entrepreneurs can use as the basis from which to operate and achieve competitive advantage. It is an important piece of research for both the process of social enterprise development in Slovenia, as well as to provide ideas and thoughts as to the way forward in this sector for other developing societies. Social enterprise is a developing field and it has been be important to develop cases to begin to explore the concept with real life actualities. The goal is to provide a clearer conceptualisation from which other social entrepreneurs can use as the basis to analyse, plan and improve social enterprise in their own specific contexts. The primary purpose of the study is thus to unpack the core elements that identify social enterprise in Slovenia using the resource-based view. The research aims to understand social enterprise within Slovenia in relation to where it occurs, which are the main industries concerned, and what are the unique resources used to promote sustainable growth. To achieve this, the research was guided by the resource-based view for social enterprise as highlighted by Day and Jean-Denis (2016) as well as that proposed by Bacq and Eddleston (2018). A mind map for a possible route towards improved implementation and understanding of social enterprise in Slovenia, was done through accessing registered social enterprises. This database was from the Ministry of Economic Development in Slovenia. An analysis of 2591 social enterprise, a desktop review of the Slovenian legislation on social enterprise and the unpacking of unique resources available to Slovenian social enterprise was done. This provided a perfect test case to show how the provision of legislation, supportive structures; financial targets, a regional vision and government mentoring social enterprise enhance a contested terrain in Slovenia. Findings highlighted that there have been sustainable successes, but not at the levels expected. It is clear that the government has created various unique resources to build and develop the social enterprise (SE) sector. From an RBV analysis of the social enterprise environment in Slovenia, it is essential to have resources such as legislation, mind-set, in migration (labour) and youth skills be created, monitored and supported. However, there is a need for improved monitoring and tighter implementation of the legislation for social enterprise to provide the solution to destructive social ills.
- Full Text:
- Date Issued: 2020
- Authors: Malila, Brett
- Date: 2020
- Subjects: Social entrepreneurship -- Slovenia , Social entrepreneurship -- Slovenia -- Case studies , Social entrepreneurship -- Law and legilstion-- Slovenia , Business enterprises -- Law and legilstion-- Slovenia
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/166436 , vital:41364
- Description: This research presents a case study on the nature of social enterprise in Slovenia. From a resource-based view (RBV), the case study has been used to show what some of the intangible resources are that can be used to promote sustainable social enterprise (SE). The purpose of this research study is to analyse social enterprises in Slovenia in order to establish a framework which other social entrepreneurs can use as the basis from which to operate and achieve competitive advantage. It is an important piece of research for both the process of social enterprise development in Slovenia, as well as to provide ideas and thoughts as to the way forward in this sector for other developing societies. Social enterprise is a developing field and it has been be important to develop cases to begin to explore the concept with real life actualities. The goal is to provide a clearer conceptualisation from which other social entrepreneurs can use as the basis to analyse, plan and improve social enterprise in their own specific contexts. The primary purpose of the study is thus to unpack the core elements that identify social enterprise in Slovenia using the resource-based view. The research aims to understand social enterprise within Slovenia in relation to where it occurs, which are the main industries concerned, and what are the unique resources used to promote sustainable growth. To achieve this, the research was guided by the resource-based view for social enterprise as highlighted by Day and Jean-Denis (2016) as well as that proposed by Bacq and Eddleston (2018). A mind map for a possible route towards improved implementation and understanding of social enterprise in Slovenia, was done through accessing registered social enterprises. This database was from the Ministry of Economic Development in Slovenia. An analysis of 2591 social enterprise, a desktop review of the Slovenian legislation on social enterprise and the unpacking of unique resources available to Slovenian social enterprise was done. This provided a perfect test case to show how the provision of legislation, supportive structures; financial targets, a regional vision and government mentoring social enterprise enhance a contested terrain in Slovenia. Findings highlighted that there have been sustainable successes, but not at the levels expected. It is clear that the government has created various unique resources to build and develop the social enterprise (SE) sector. From an RBV analysis of the social enterprise environment in Slovenia, it is essential to have resources such as legislation, mind-set, in migration (labour) and youth skills be created, monitored and supported. However, there is a need for improved monitoring and tighter implementation of the legislation for social enterprise to provide the solution to destructive social ills.
- Full Text:
- Date Issued: 2020
A critical analysis of the de-peasantisation process in Nepal with specific reference to the role of state land policies since the 1950s
- Authors: Basnet, Jagat
- Date: 2020
- Subjects: Land tenure -- Nepal , Land reform -- Law and legislation -- Nepal , Nepal -- Politics and government , Peasants -- Nepal -- Economic conditions , Panchayat -- Nepal
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/138716 , vital:37667
- Description: The principal objective of this thesis is to offer a critical analysis of the process of de-peasantisation in Nepal since 1950, with a particular focus on the capitalist neo-liberal restructuring of the economy beginning in the early 1990s. The analysis begins by tracing the legacy of feudal land practices and landholdings from the pre-1950 Rana and Shah dynasties. It was under these feudal dynasties that economic and political institutions of extraction first emerged, leading to a landlord-peasant agrarian economy in which peasants (often as tenants/sharecroppers and smallholders) were subordinate to the power nexus between feudal landlords and the ruling dynasties. After 1950, a window of democratic opening was soon interrupted by the formation of the party-less Panchayat system, which lasted from 1960 to 1990. In 1964, a major land reform measure was enacted under the Lands Act, with the goal of enhancing the security and livelihood of the peasantry. However, this process was met with significant resistance by feudal landlords, and actually led to deepening insecurity and the loss of land by peasants, with farmers belonging to lower castes and indigenous groups experiencing this with a greater degree of intensity. The overall result of this period was the beginnings of what is referred to in this study as de-peasantisation. This line of analysis shows that the institutions of extraction remained firmly in place even after the reforms of this period. Finally, the neo-liberal period, which was marked by land titling, the marketisation of land, and the commercialisation of agriculture, represents the late entry of capitalism into Nepal. This period saw the deepening and widening of the process of de-peasantisation, including further loss of peasants’ access to land and a general turn to wage-labour. In this regard, despite propagating the slogan ‘land to the tillers’, the major political parties in Nepal (including the Maoist party) have failed to defend the interests of the peasantry. Some progressive civil society groups have recently sought to do better, but there is also evidence of peasant organisations themselves seeking to resist and oppose the de-peasantisation effects of neo-liberal restructuring. This thesis thus considers the form and extent of de-peasantisation in Nepal, and some responses to it, over an extended period. A broad Marxist-based political economy perspective has been adopted in pursuing the principal thesis objective, but one which argues that there is a symbiotic relationship between economic and political power, such that the latter is not reducible to the former. The thesis draws upon original fieldwork in twenty districts of Nepal, including through the use of a survey, interviews, observations, case studies, and focus group discussions, thus combining both quantitative and qualitative research methods. Based on this fieldwork, it becomes clear that (i) there are major social, economic, and political forces behind the processes of de-peasantisation in the studied districts (and in Nepal more broadly), and that (ii) the Nepali peasantry is becoming increasingly landless, or land-short, and subject to processes of proletarianisation.
- Full Text:
- Date Issued: 2020
- Authors: Basnet, Jagat
- Date: 2020
- Subjects: Land tenure -- Nepal , Land reform -- Law and legislation -- Nepal , Nepal -- Politics and government , Peasants -- Nepal -- Economic conditions , Panchayat -- Nepal
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/138716 , vital:37667
- Description: The principal objective of this thesis is to offer a critical analysis of the process of de-peasantisation in Nepal since 1950, with a particular focus on the capitalist neo-liberal restructuring of the economy beginning in the early 1990s. The analysis begins by tracing the legacy of feudal land practices and landholdings from the pre-1950 Rana and Shah dynasties. It was under these feudal dynasties that economic and political institutions of extraction first emerged, leading to a landlord-peasant agrarian economy in which peasants (often as tenants/sharecroppers and smallholders) were subordinate to the power nexus between feudal landlords and the ruling dynasties. After 1950, a window of democratic opening was soon interrupted by the formation of the party-less Panchayat system, which lasted from 1960 to 1990. In 1964, a major land reform measure was enacted under the Lands Act, with the goal of enhancing the security and livelihood of the peasantry. However, this process was met with significant resistance by feudal landlords, and actually led to deepening insecurity and the loss of land by peasants, with farmers belonging to lower castes and indigenous groups experiencing this with a greater degree of intensity. The overall result of this period was the beginnings of what is referred to in this study as de-peasantisation. This line of analysis shows that the institutions of extraction remained firmly in place even after the reforms of this period. Finally, the neo-liberal period, which was marked by land titling, the marketisation of land, and the commercialisation of agriculture, represents the late entry of capitalism into Nepal. This period saw the deepening and widening of the process of de-peasantisation, including further loss of peasants’ access to land and a general turn to wage-labour. In this regard, despite propagating the slogan ‘land to the tillers’, the major political parties in Nepal (including the Maoist party) have failed to defend the interests of the peasantry. Some progressive civil society groups have recently sought to do better, but there is also evidence of peasant organisations themselves seeking to resist and oppose the de-peasantisation effects of neo-liberal restructuring. This thesis thus considers the form and extent of de-peasantisation in Nepal, and some responses to it, over an extended period. A broad Marxist-based political economy perspective has been adopted in pursuing the principal thesis objective, but one which argues that there is a symbiotic relationship between economic and political power, such that the latter is not reducible to the former. The thesis draws upon original fieldwork in twenty districts of Nepal, including through the use of a survey, interviews, observations, case studies, and focus group discussions, thus combining both quantitative and qualitative research methods. Based on this fieldwork, it becomes clear that (i) there are major social, economic, and political forces behind the processes of de-peasantisation in the studied districts (and in Nepal more broadly), and that (ii) the Nepali peasantry is becoming increasingly landless, or land-short, and subject to processes of proletarianisation.
- Full Text:
- Date Issued: 2020
A critical analysis of the South African turnover tax system
- Authors: Chiromo, Samuel John
- Date: 2020
- Subjects: Small business -- Taxation -- South Africa , Small business -- South Africa -- Finance , Turnover tax -- South Africa , Government aid to small business -- South Africa , Tax incentives -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/166103 , vital:41329
- Description: The objective of the turnover tax system is to reduce the administrative burden on micro businesses and to contribute positively to boosting these businesses and the economic growth of South Africa. The over-arching goal of this research was to analyse the South African turnover tax to investigate to what extent the turnover tax system complies with generally accepted principles of a good tax system. The research was conducted within an interpretative post-positivism paradigm, applied a qualitative research methodology, and a doctrinal research method. A detailed review of the literature was conducted to establish the nature of South African turnover tax system and the extent of its compliance with generally accepted principles of a good tax system. The literature review included an in-depth analysis of the South African turnover tax system, an in-depth analysis of generally accepted principles of a good tax system, and an investigation of the extent to which turnover tax system complies with various elements of the principles of a good tax system. It was found in this study that the turnover tax system does not comply with certain of the elements of generally accepted principles of a good tax system and the study proposed several recommendations for the improvement of the turnover tax system. These recommendations include the establishment of training initiatives for micro business owners, reviewing the regulations pertaining to turnover tax and providing digital administration of turnover tax.
- Full Text:
- Date Issued: 2020
- Authors: Chiromo, Samuel John
- Date: 2020
- Subjects: Small business -- Taxation -- South Africa , Small business -- South Africa -- Finance , Turnover tax -- South Africa , Government aid to small business -- South Africa , Tax incentives -- South Africa
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/166103 , vital:41329
- Description: The objective of the turnover tax system is to reduce the administrative burden on micro businesses and to contribute positively to boosting these businesses and the economic growth of South Africa. The over-arching goal of this research was to analyse the South African turnover tax to investigate to what extent the turnover tax system complies with generally accepted principles of a good tax system. The research was conducted within an interpretative post-positivism paradigm, applied a qualitative research methodology, and a doctrinal research method. A detailed review of the literature was conducted to establish the nature of South African turnover tax system and the extent of its compliance with generally accepted principles of a good tax system. The literature review included an in-depth analysis of the South African turnover tax system, an in-depth analysis of generally accepted principles of a good tax system, and an investigation of the extent to which turnover tax system complies with various elements of the principles of a good tax system. It was found in this study that the turnover tax system does not comply with certain of the elements of generally accepted principles of a good tax system and the study proposed several recommendations for the improvement of the turnover tax system. These recommendations include the establishment of training initiatives for micro business owners, reviewing the regulations pertaining to turnover tax and providing digital administration of turnover tax.
- Full Text:
- Date Issued: 2020