The use of lesson study to assist junior primary ‘in-service training teachers’ to develop learners’ number sense using number talks
- Authors: Ortman-Gaweseb, Dominika
- Date: 2023-03-30
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408750 , vital:70522
- Description: Thesis embargoed. To be released in 2025. , Thesis (MEd) -- Faculty of Education, Education, 2023
- Full Text:
- Date Issued: 2023-03-30
- Authors: Ortman-Gaweseb, Dominika
- Date: 2023-03-30
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/408750 , vital:70522
- Description: Thesis embargoed. To be released in 2025. , Thesis (MEd) -- Faculty of Education, Education, 2023
- Full Text:
- Date Issued: 2023-03-30
A value alignment smart city stakeholder model
- Van der Hoogen, Anthea Vivian
- Authors: Van der Hoogen, Anthea Vivian
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54129 , vital:46309
- Description: The concept of a Smart City has evolved over the last three decades and has attracted the increasing interest of the scientific research community. Unfortunately, many Smart City projects and initiatives do not provide the value expected by all the stakeholders. Many of the reasons for this relate to a lack of data management, data integration, data access and stakeholder participation. People are an integral part of any city’s ecosystem, and the Smart City concept was introduced to address the challenges of an ever-growing global population leading to the risk of depletion of economic, environmental and social resources. The problem addressed in this study is based on the challenges preventing the creation of the value of smart cities or stakeholders. Limited research has been published on the status of Smart City initiatives or on the impact of various success factors on the potential value creation for stakeholders including citizens. Studies on initiatives in developing countries, such as South Africa are even less. Whilst some challenges and constraints related to smart cities in Africa have been reported, there are no studies reporting on initiatives across the data value chain that consider all types of stakeholders, nor the impact of these initiatives. This study addressed this gap in research and designed a theoretical Value Alignment Smart City Stakeholder (VASCS) Model based on a Systematic Literature Review and a review of related theories. The model has important components that should form part of any Smart City project or Smart City initiative. These five main components are: 1) nine Smart City dimensions with related success factors; 2) four stakeholder roles (enablers, providers, utilisers and users); 3) the data value chain; and 4) the five phases of stakeholder benefits/value realisation that can be linked to; 5) stakeholder value alignment. This study applied the VASCS Model to Smart City initiatives in two case studies in the Eastern Cape Province of South Africa, which were the Nelson Mandela Bay and Buffalo City to investigate and understand the status of such initiatives and the alignment of value thereof. The stakeholder interviews were conducted in two rounds with various stakeholders of Smart City initiatives, referred to as cases in the two case studies. An expert review of the VASCS Model was conducted with eight experts in the field of Information Systems and Smart Cities. The findings of this review served to confirm the components of the model, with only minor improvements recommended. It was confirmed that all of the components need to be considered in planning Smart City projects. The first round consisted of six interviews with enablers and providers and the second round consisted of 22 interviews with users, utilisers and citizens. The interviews investigated the value and impact experienced by stakeholders of these initiatives, with a particular focus on the users, utilisers and citizens of the cases. The interview data was transcribed and qualitatively analysed by using Atlas.tiand Excel. The data was analysed according to the Technological, Organisational and Environmental theory constructs and other identified themes. The interview analysis findings revealed several drivers for these initiatives, which were primarily cost reduction, integration and quality assurance. The results also highlighted access to resources, such as technical skills as a challenge. Another challenge identified was connectivity related to access to data and the digital and physical divide that can impact decision making. The main benefits of Smart City initiatives highlighted were the provision of infrastructure, education and training and digitalisation. The theoretical contribution of this study is the VASCS Model, which can assist other researchers and practitioners with knowledge of the factors, drivers, challenges and value obtained in Smart City initiatives. The model has two supplementary components: A Stakeholder Classification Model and a Smart City Success Factor Evaluation Template. The practical contribution of this study is the potential use of the VASCS Model by practitioners, city management, researchers and other stakeholders, who can use the model, with the related model and template for planning and evaluating Smart City initiatives. The model can be used to classify the digital activities according to a Smart City’s success factors while evaluating the value created by these activities. The impact of these initiatives can then be assessed through value realisation and alignment for stakeholders. The scientific contribution is the adoption of the model to the cases in the Eastern Cape. To reveal in depth, rich, interview findings that provide important lessons learnt relating to the value created for the stakeholders and the addition of these findings to the body of knowledge. , Thesis (PhD) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Van der Hoogen, Anthea Vivian
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54129 , vital:46309
- Description: The concept of a Smart City has evolved over the last three decades and has attracted the increasing interest of the scientific research community. Unfortunately, many Smart City projects and initiatives do not provide the value expected by all the stakeholders. Many of the reasons for this relate to a lack of data management, data integration, data access and stakeholder participation. People are an integral part of any city’s ecosystem, and the Smart City concept was introduced to address the challenges of an ever-growing global population leading to the risk of depletion of economic, environmental and social resources. The problem addressed in this study is based on the challenges preventing the creation of the value of smart cities or stakeholders. Limited research has been published on the status of Smart City initiatives or on the impact of various success factors on the potential value creation for stakeholders including citizens. Studies on initiatives in developing countries, such as South Africa are even less. Whilst some challenges and constraints related to smart cities in Africa have been reported, there are no studies reporting on initiatives across the data value chain that consider all types of stakeholders, nor the impact of these initiatives. This study addressed this gap in research and designed a theoretical Value Alignment Smart City Stakeholder (VASCS) Model based on a Systematic Literature Review and a review of related theories. The model has important components that should form part of any Smart City project or Smart City initiative. These five main components are: 1) nine Smart City dimensions with related success factors; 2) four stakeholder roles (enablers, providers, utilisers and users); 3) the data value chain; and 4) the five phases of stakeholder benefits/value realisation that can be linked to; 5) stakeholder value alignment. This study applied the VASCS Model to Smart City initiatives in two case studies in the Eastern Cape Province of South Africa, which were the Nelson Mandela Bay and Buffalo City to investigate and understand the status of such initiatives and the alignment of value thereof. The stakeholder interviews were conducted in two rounds with various stakeholders of Smart City initiatives, referred to as cases in the two case studies. An expert review of the VASCS Model was conducted with eight experts in the field of Information Systems and Smart Cities. The findings of this review served to confirm the components of the model, with only minor improvements recommended. It was confirmed that all of the components need to be considered in planning Smart City projects. The first round consisted of six interviews with enablers and providers and the second round consisted of 22 interviews with users, utilisers and citizens. The interviews investigated the value and impact experienced by stakeholders of these initiatives, with a particular focus on the users, utilisers and citizens of the cases. The interview data was transcribed and qualitatively analysed by using Atlas.tiand Excel. The data was analysed according to the Technological, Organisational and Environmental theory constructs and other identified themes. The interview analysis findings revealed several drivers for these initiatives, which were primarily cost reduction, integration and quality assurance. The results also highlighted access to resources, such as technical skills as a challenge. Another challenge identified was connectivity related to access to data and the digital and physical divide that can impact decision making. The main benefits of Smart City initiatives highlighted were the provision of infrastructure, education and training and digitalisation. The theoretical contribution of this study is the VASCS Model, which can assist other researchers and practitioners with knowledge of the factors, drivers, challenges and value obtained in Smart City initiatives. The model has two supplementary components: A Stakeholder Classification Model and a Smart City Success Factor Evaluation Template. The practical contribution of this study is the potential use of the VASCS Model by practitioners, city management, researchers and other stakeholders, who can use the model, with the related model and template for planning and evaluating Smart City initiatives. The model can be used to classify the digital activities according to a Smart City’s success factors while evaluating the value created by these activities. The impact of these initiatives can then be assessed through value realisation and alignment for stakeholders. The scientific contribution is the adoption of the model to the cases in the Eastern Cape. To reveal in depth, rich, interview findings that provide important lessons learnt relating to the value created for the stakeholders and the addition of these findings to the body of knowledge. , Thesis (PhD) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
The design of an infectious disease centre of excellence for the study of infectious diseases at Livingstone Hospital, Gqeberha
- L’ange, Christopher Jonathan
- Authors: L’ange, Christopher Jonathan
- Date: 2021-12
- Subjects: Hospital buildings –South Africa – Port Elizabeth –design and plans , Hospitals buildings –Disinfection –Port Elizabeth
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58683 , vital:59985
- Description: The COVID-19 virus showed the world how under-prepared it was to cope with a pandemic. It also raised an awareness in the world that a highly communicable disease can begin anywhere, and without proper monitoring and reporting can spread to become a global pandemic. The South African Health Department has been under significant stress and on the brink of collapse during the successive waves of the pandemic due to the lack of healthcare workers, medical doctors, infectious disease specialists and epidemiologists as well inadequate medical and clinical infrastructure. The infectious disease specialty in South Africa is also in crisis, prompting the Infectious Disease Society of South Africa to plead with the Health Department and universities to fund projects that support learning and research into infectious diseases, virology, and epidemiology. This project proposes the design of an Infectious Disease Centre of Excellence for the Study of Infectious Diseases at Livingstone Hospital, Gqeberha which focuses on the research, teaching and learning, and healing of infectious diseases in a ho listic building design incorporating biosafety research laboratories, an infectious disease ward and a centre of excellence. The methodology used was to research existing precedent studies that are focused on the research, teaching and learning, and healing of infectious diseases as well as researching a theoretical framework based on holism and systemic architec ture. This theoretical framework, coupled with a careful analysis of the relation ship of each highly specialised space with the other space components leads to the design of an Infectious Disease Centre of Excellence for the Study of Infectious Diseases which responds to the urgent need expressed above as well as providing a design which promotes the well-being of all users. The facility also enhances the Livingstone Hospital precinct. Key Words: Infectious Diseases, Laboratory, Ward, Centre of Excellence, Bio-Safe ty, Holism, Systemic. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: L’ange, Christopher Jonathan
- Date: 2021-12
- Subjects: Hospital buildings –South Africa – Port Elizabeth –design and plans , Hospitals buildings –Disinfection –Port Elizabeth
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58683 , vital:59985
- Description: The COVID-19 virus showed the world how under-prepared it was to cope with a pandemic. It also raised an awareness in the world that a highly communicable disease can begin anywhere, and without proper monitoring and reporting can spread to become a global pandemic. The South African Health Department has been under significant stress and on the brink of collapse during the successive waves of the pandemic due to the lack of healthcare workers, medical doctors, infectious disease specialists and epidemiologists as well inadequate medical and clinical infrastructure. The infectious disease specialty in South Africa is also in crisis, prompting the Infectious Disease Society of South Africa to plead with the Health Department and universities to fund projects that support learning and research into infectious diseases, virology, and epidemiology. This project proposes the design of an Infectious Disease Centre of Excellence for the Study of Infectious Diseases at Livingstone Hospital, Gqeberha which focuses on the research, teaching and learning, and healing of infectious diseases in a ho listic building design incorporating biosafety research laboratories, an infectious disease ward and a centre of excellence. The methodology used was to research existing precedent studies that are focused on the research, teaching and learning, and healing of infectious diseases as well as researching a theoretical framework based on holism and systemic architec ture. This theoretical framework, coupled with a careful analysis of the relation ship of each highly specialised space with the other space components leads to the design of an Infectious Disease Centre of Excellence for the Study of Infectious Diseases which responds to the urgent need expressed above as well as providing a design which promotes the well-being of all users. The facility also enhances the Livingstone Hospital precinct. Key Words: Infectious Diseases, Laboratory, Ward, Centre of Excellence, Bio-Safe ty, Holism, Systemic. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2021
- Full Text:
- Date Issued: 2021-12
Engineering nanocatalysts using mixed metals for hydrodesulfurization of fuel oil
- Authors: Majodina, Siphumelele
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53861 , vital:46021
- Description: Crude oil is a complex blend containing thousands of hydrocarbons, non-hydrocarbon compounds and heavy metals. These hydrocarbons are mixed with variable quantities of sulfur-, nitrogen-, and oxygen-containing compounds. The combustion of fuel containing organosulfur compounds results in the emission of sulfur oxides (SOx) into the atmosphere. These toxic gases escape into the atmosphere resulting in air pollution, which is a large contributor to global warming. Air pollution also causes pulmonary diseases, allergies and may even lead to human death. It can also cause harm to other living organisms such as animals and food crops. Thus, mandating the reduction of sulfur in organosulfur compounds in fuel to <10 ppmS by the environmental protection agency. Several studies have been conducted to remove sulfur from fuels, most of which have focused on removing refractory sulfur compounds due to the difficulty in removing sulfur in these compounds. However, the currently employed hydrodesulfurization (HDS) catalysts suffer in producing fuels complying with the future standards of fuels quality. Generally, HDS catalysts are made up of metallic components, Co (Ni) and Mo (W), on porous supports, the catalytic activity of these catalysts strongly depends on the amount of NiWS (CoMoS) phases in it and to the extent in which these phases are exposed on the catalyst support surfaces and this is engineered using chelating agents and size of catalysts. To this end, nanosized materials (nanocatalysts) are considered most suitable, as reported active phases of HDS catalysts are exposed, hence improving the hydrodesulfurization of sulfur-containing compounds in fuels. Nanocatalysts results in nanoparticles and when impregnated on a support will results in high surface area, and enhances electronic property, which increases the activity of the catalyst allowing the most refractory sulfur to be removed. The addition of chelating agents such as EDTA, acetic acid, and citric acid further improves the activity of the catalysts by producing more active phases on the catalyst. In this research project, nanocatalysts will be synthesised using mixed metals with and without chelating agents and tested for HDS activity and selectivity towards sulfur using refractory organosulfur compounds in fuels under industrial HDS conditions. This work was divided into two sections, and this dissertation summarizes the research outcomes of each phase. The first section examines the effect of chelating ligands, namely, ethylenediaminetetraacetic acid (EDTA), citric acid (CA), and acetic acid (AA), on CoMo HDS activity and the sulfidation mechanism. In this study, chelating ligands seem to have a beneficial effect on HDS activity. Detailed mechanistic aspects of interactions between chelating ligands and metallic species (Co-chelating ligands) were also studied. Characterization by SC-XRD revealed that the presence of the chelating ligand result in the formation of complex with cobalt, and the effect of this complex was shown by TG-DSC analysis. This showed that the presence of chelating ligand leads a to delay of cobalt sulfidation as the complex decomposes at higher temperatures, which was the main cause of improving HDS activity. It was also shown that chelating ligands play a role in dispersion of metal oxides and sulfided metal oxides (TEM and XPS). XPS results showed low MoS2 phase for CoMo/Al2O3 (45%), while CoMo-EDTA/Al2O3 (63%) catalyst resulted in high MoS2 phases. From all the catalysts, CoMo-CA/Al2O3 (98%) gave the highest catalytic activity, and the increase in activity could be attributed to the formation of octahedral molybdenum oxides as they are easily reducible during sulfidation and result in more dispersed active phases and weak metal-support interaction. The second section examines the effect of a promoter (Rh) and different chelating ligands (EDTA, AA, and CA) on the catalyst RhMo supported with alumina. In this phase, rhodium was used as promoter, the following trend for catalytic activity was observed: RhMo/Al2O3 (88%) > RhMo-AA/Al2O3 (73%) > RhMo-CA/Al2O3 (72%) > RhMo-EDTA/Al2O3 (68%). This could be that the addition of chelating ligand complexed both metallic species retarding sulfidation of both metals, hence lowering the HDS activity. Studies show that it is possible for the citric acid to complex with both promoter and an active metal (Mo), and this might result in the formation of molybdenum dimers, trimers and tetramers which are difficult to sulfide. XPS analysis showed that unchelated catalyst have more MoS2 phases of 63%, hence higher dispersion than the chelated catalyst, this could be the reason for high activity in RhMo/Al2O3 (88%) catalyst. , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Majodina, Siphumelele
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53861 , vital:46021
- Description: Crude oil is a complex blend containing thousands of hydrocarbons, non-hydrocarbon compounds and heavy metals. These hydrocarbons are mixed with variable quantities of sulfur-, nitrogen-, and oxygen-containing compounds. The combustion of fuel containing organosulfur compounds results in the emission of sulfur oxides (SOx) into the atmosphere. These toxic gases escape into the atmosphere resulting in air pollution, which is a large contributor to global warming. Air pollution also causes pulmonary diseases, allergies and may even lead to human death. It can also cause harm to other living organisms such as animals and food crops. Thus, mandating the reduction of sulfur in organosulfur compounds in fuel to <10 ppmS by the environmental protection agency. Several studies have been conducted to remove sulfur from fuels, most of which have focused on removing refractory sulfur compounds due to the difficulty in removing sulfur in these compounds. However, the currently employed hydrodesulfurization (HDS) catalysts suffer in producing fuels complying with the future standards of fuels quality. Generally, HDS catalysts are made up of metallic components, Co (Ni) and Mo (W), on porous supports, the catalytic activity of these catalysts strongly depends on the amount of NiWS (CoMoS) phases in it and to the extent in which these phases are exposed on the catalyst support surfaces and this is engineered using chelating agents and size of catalysts. To this end, nanosized materials (nanocatalysts) are considered most suitable, as reported active phases of HDS catalysts are exposed, hence improving the hydrodesulfurization of sulfur-containing compounds in fuels. Nanocatalysts results in nanoparticles and when impregnated on a support will results in high surface area, and enhances electronic property, which increases the activity of the catalyst allowing the most refractory sulfur to be removed. The addition of chelating agents such as EDTA, acetic acid, and citric acid further improves the activity of the catalysts by producing more active phases on the catalyst. In this research project, nanocatalysts will be synthesised using mixed metals with and without chelating agents and tested for HDS activity and selectivity towards sulfur using refractory organosulfur compounds in fuels under industrial HDS conditions. This work was divided into two sections, and this dissertation summarizes the research outcomes of each phase. The first section examines the effect of chelating ligands, namely, ethylenediaminetetraacetic acid (EDTA), citric acid (CA), and acetic acid (AA), on CoMo HDS activity and the sulfidation mechanism. In this study, chelating ligands seem to have a beneficial effect on HDS activity. Detailed mechanistic aspects of interactions between chelating ligands and metallic species (Co-chelating ligands) were also studied. Characterization by SC-XRD revealed that the presence of the chelating ligand result in the formation of complex with cobalt, and the effect of this complex was shown by TG-DSC analysis. This showed that the presence of chelating ligand leads a to delay of cobalt sulfidation as the complex decomposes at higher temperatures, which was the main cause of improving HDS activity. It was also shown that chelating ligands play a role in dispersion of metal oxides and sulfided metal oxides (TEM and XPS). XPS results showed low MoS2 phase for CoMo/Al2O3 (45%), while CoMo-EDTA/Al2O3 (63%) catalyst resulted in high MoS2 phases. From all the catalysts, CoMo-CA/Al2O3 (98%) gave the highest catalytic activity, and the increase in activity could be attributed to the formation of octahedral molybdenum oxides as they are easily reducible during sulfidation and result in more dispersed active phases and weak metal-support interaction. The second section examines the effect of a promoter (Rh) and different chelating ligands (EDTA, AA, and CA) on the catalyst RhMo supported with alumina. In this phase, rhodium was used as promoter, the following trend for catalytic activity was observed: RhMo/Al2O3 (88%) > RhMo-AA/Al2O3 (73%) > RhMo-CA/Al2O3 (72%) > RhMo-EDTA/Al2O3 (68%). This could be that the addition of chelating ligand complexed both metallic species retarding sulfidation of both metals, hence lowering the HDS activity. Studies show that it is possible for the citric acid to complex with both promoter and an active metal (Mo), and this might result in the formation of molybdenum dimers, trimers and tetramers which are difficult to sulfide. XPS analysis showed that unchelated catalyst have more MoS2 phases of 63%, hence higher dispersion than the chelated catalyst, this could be the reason for high activity in RhMo/Al2O3 (88%) catalyst. , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-12
Statistical and Mathematical Learning: an application to fraud detection and prevention
- Authors: Hamlomo, Sisipho
- Date: 2022-04-06
- Subjects: Credit card fraud , Bootstrap (Statistics) , Support vector machines , Neural networks (Computer science) , Decision trees , Machine learning , Cross-validation , Imbalanced data
- Language: English
- Type: Master's thesis , text
- Identifier: http://hdl.handle.net/10962/233795 , vital:50128
- Description: Credit card fraud is an ever-growing problem. There has been a rapid increase in the rate of fraudulent activities in recent years resulting in a considerable loss to several organizations, companies, and government agencies. Many researchers have focused on detecting fraudulent behaviours early using advanced machine learning techniques. However, credit card fraud detection is not a straightforward task since fraudulent behaviours usually differ for each attempt and the dataset is highly imbalanced, that is, the frequency of non-fraudulent cases outnumbers the frequency of fraudulent cases. In the case of the European credit card dataset, we have a ratio of approximately one fraudulent case to five hundred and seventy-eight non-fraudulent cases. Different methods were implemented to overcome this problem, namely random undersampling, one-sided sampling, SMOTE combined with Tomek links and parameter tuning. Predictive classifiers, namely logistic regression, decision trees, k-nearest neighbour, support vector machine and multilayer perceptrons, are applied to predict if a transaction is fraudulent or non-fraudulent. The model's performance is evaluated based on recall, precision, F1-score, the area under receiver operating characteristics curve, geometric mean and Matthew correlation coefficient. The results showed that the logistic regression classifier performed better than other classifiers except when the dataset was oversampled. , Thesis (MSc) -- Faculty of Science, Statistics, 2022
- Full Text:
- Date Issued: 2022-04-06
- Authors: Hamlomo, Sisipho
- Date: 2022-04-06
- Subjects: Credit card fraud , Bootstrap (Statistics) , Support vector machines , Neural networks (Computer science) , Decision trees , Machine learning , Cross-validation , Imbalanced data
- Language: English
- Type: Master's thesis , text
- Identifier: http://hdl.handle.net/10962/233795 , vital:50128
- Description: Credit card fraud is an ever-growing problem. There has been a rapid increase in the rate of fraudulent activities in recent years resulting in a considerable loss to several organizations, companies, and government agencies. Many researchers have focused on detecting fraudulent behaviours early using advanced machine learning techniques. However, credit card fraud detection is not a straightforward task since fraudulent behaviours usually differ for each attempt and the dataset is highly imbalanced, that is, the frequency of non-fraudulent cases outnumbers the frequency of fraudulent cases. In the case of the European credit card dataset, we have a ratio of approximately one fraudulent case to five hundred and seventy-eight non-fraudulent cases. Different methods were implemented to overcome this problem, namely random undersampling, one-sided sampling, SMOTE combined with Tomek links and parameter tuning. Predictive classifiers, namely logistic regression, decision trees, k-nearest neighbour, support vector machine and multilayer perceptrons, are applied to predict if a transaction is fraudulent or non-fraudulent. The model's performance is evaluated based on recall, precision, F1-score, the area under receiver operating characteristics curve, geometric mean and Matthew correlation coefficient. The results showed that the logistic regression classifier performed better than other classifiers except when the dataset was oversampled. , Thesis (MSc) -- Faculty of Science, Statistics, 2022
- Full Text:
- Date Issued: 2022-04-06
The design of a furniture Factory in Airport Valley, Gqeberha
- Authors: Hetherington, Ian Craig
- Date: 2021-12
- Subjects: Stores, Retail – South Africa – Walmer--Designs and plans , Furniture --Reproduction , Interior architecture – Walmer – Designs and plans
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58738 , vital:60080
- Description: We are slowly destroying our planet. By now, it is understood that humanity cannot continue with a system of production that continuously converts our finite supply of usable materials into unusable waste. In South Africa, the majority of our waste disappears into landfills but a certain percentage of this waste finds new life. e in the informal and economically repressed communities that have been driven to using this waste out of economic necessity. This treatise aims to explore the potential to provide a dignified built environment through a regenerative architecture that employs tectonic thinking to build with waste in an informal communityThe proposed building for this treatise is a furniture factory, based in Airport Valley, Gqeberha, that is both built from and builds with waste. A series of investigations will be conducted around the theoretical discourse of waste and tectonics in architecture, the nature of productive buildings, the coontext within which the factory will be placed, and the specific processes the factory will engage in. Culminating in the final design of a building that ccan play a socially, economically, and environmentally positive role in one of the many communities that have been left behind by the liberation movement.. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Hetherington, Ian Craig
- Date: 2021-12
- Subjects: Stores, Retail – South Africa – Walmer--Designs and plans , Furniture --Reproduction , Interior architecture – Walmer – Designs and plans
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58738 , vital:60080
- Description: We are slowly destroying our planet. By now, it is understood that humanity cannot continue with a system of production that continuously converts our finite supply of usable materials into unusable waste. In South Africa, the majority of our waste disappears into landfills but a certain percentage of this waste finds new life. e in the informal and economically repressed communities that have been driven to using this waste out of economic necessity. This treatise aims to explore the potential to provide a dignified built environment through a regenerative architecture that employs tectonic thinking to build with waste in an informal communityThe proposed building for this treatise is a furniture factory, based in Airport Valley, Gqeberha, that is both built from and builds with waste. A series of investigations will be conducted around the theoretical discourse of waste and tectonics in architecture, the nature of productive buildings, the coontext within which the factory will be placed, and the specific processes the factory will engage in. Culminating in the final design of a building that ccan play a socially, economically, and environmentally positive role in one of the many communities that have been left behind by the liberation movement.. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2021
- Full Text:
- Date Issued: 2021-12
The design of a community sports centre in Alexandra township, Johannesburg
- Authors: Makhele, Busang
- Date: 2021-12
- Subjects: Sports facilities --South Africa – Alexandra -- Designs and plans , Recreation centers -- South Africa –Johannesburg
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58666 , vital:59978
- Description: The post-apartheid city is an unfinished product. It is simultaneously being made and unmade. South African urban environments reinforce and reflect urban segregation and inequality. They are characterised by the remanence of the apartheid city defined by sprawl, placelessness and monotony. Nowhere else has this reality been truer and more visible than in township settlements. Townships settlements are the polar opposite of suburbia. They are typically situated on the outskirts of urban environments with unpleasant living conditions characterised by the lack of public facilities and spaces, adequate resources and under-utilised left-over space. The poor urban conditions in township settlements is where this treatise has decided to position itself. The treatise will use both primary and secondary data resources collected from site visits, observations made, analytical maps and diagrams. The secondary data, includes books, precedent studies, articles and academic journals. The findings indicate that in order for the design intervention to be appropriate and successful, it is important that principles which improve urban qualities and a sense of place and belonging are engaged with and understood, in order to cater to the needs of the community. In conclusion, the intention of this treatise is to design a Community Sports Centre in Alexandra Township, Johannesburg as a means of improving the urban quality by restructuring and reframing public and community space in the township. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Makhele, Busang
- Date: 2021-12
- Subjects: Sports facilities --South Africa – Alexandra -- Designs and plans , Recreation centers -- South Africa –Johannesburg
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58666 , vital:59978
- Description: The post-apartheid city is an unfinished product. It is simultaneously being made and unmade. South African urban environments reinforce and reflect urban segregation and inequality. They are characterised by the remanence of the apartheid city defined by sprawl, placelessness and monotony. Nowhere else has this reality been truer and more visible than in township settlements. Townships settlements are the polar opposite of suburbia. They are typically situated on the outskirts of urban environments with unpleasant living conditions characterised by the lack of public facilities and spaces, adequate resources and under-utilised left-over space. The poor urban conditions in township settlements is where this treatise has decided to position itself. The treatise will use both primary and secondary data resources collected from site visits, observations made, analytical maps and diagrams. The secondary data, includes books, precedent studies, articles and academic journals. The findings indicate that in order for the design intervention to be appropriate and successful, it is important that principles which improve urban qualities and a sense of place and belonging are engaged with and understood, in order to cater to the needs of the community. In conclusion, the intention of this treatise is to design a Community Sports Centre in Alexandra Township, Johannesburg as a means of improving the urban quality by restructuring and reframing public and community space in the township. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2021
- Full Text:
- Date Issued: 2021-12
The impact of transformed landscapes on the resource selection and occupancy of specialized browsing species in a lowland fynbos and renosterveld ecosystem
- Swanepoel, Hermanus Izak Johannes
- Authors: Swanepoel, Hermanus Izak Johannes
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54132 , vital:46308
- Description: Human activities have dramatically transformed the natural environment over the last century. In most cases these activities have resulted in the destruction and fragmentation of habitats. However, in some areas the transformation of landscapes through agriculture have created novel habitats which could benefit some species. The effect of these transformed landscapes on the resource selection and occupancy of antelope species in different vegetation types such as fynbos and renosterveld are still understudied. In order to investigate this,we conducted a study in the Overberg region of the Western Cape, South Africa. We studied theoccupancy and habitat useof five specialist browsing species (Tragelaphus scriptus sylvaticus(bushbuck), Rhaphicerus melanotis(cape grysbok), Sylvicapra grimmia(common duiker), Palea Capreolus(grey rhebok) and Rhaphicerus campestris(steenbok)) within a transformed landscape. We collected speciesdetection/ non-detectionand presence/ absence data using camera traps and road strip counts.Usinga single season, single species occupancy framework as a surrogate for habitat usewedeterminedhow transformed landscapes affected their occupancy. Using aniche factor analysis and resource selection functions wedetermine how transformed landscapes affected the resource selectionof these species. Our results from the resource selection analysis indicated that steenbok, grey rhebok, andcommon duiker included crops such as wheat and planted pastures in their resource selection while also including natural vegetation. Cape grysbok and bushbuck selected predominantly for natural vegetation areas such as critical biodiversity areas and ecological support areas while also including some crops in their resource selection. Our results from the occupancy analysis indicatedthat steenbok, grey rhebok and common duiker had a higher occupancy in the transformed landscape than in the natural landscape. Bushbuck and Cape grysbok showed little to no difference in their occupancy between land use types. The insight provided by our results will allow practitioners to maximise the potentialof these mosaic landscape in the Overberg for mammal conservation.The study also provides a baseline from which further research and monitoring programs can be developed to further understand the dynamics of this landscape. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Swanepoel, Hermanus Izak Johannes
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54132 , vital:46308
- Description: Human activities have dramatically transformed the natural environment over the last century. In most cases these activities have resulted in the destruction and fragmentation of habitats. However, in some areas the transformation of landscapes through agriculture have created novel habitats which could benefit some species. The effect of these transformed landscapes on the resource selection and occupancy of antelope species in different vegetation types such as fynbos and renosterveld are still understudied. In order to investigate this,we conducted a study in the Overberg region of the Western Cape, South Africa. We studied theoccupancy and habitat useof five specialist browsing species (Tragelaphus scriptus sylvaticus(bushbuck), Rhaphicerus melanotis(cape grysbok), Sylvicapra grimmia(common duiker), Palea Capreolus(grey rhebok) and Rhaphicerus campestris(steenbok)) within a transformed landscape. We collected speciesdetection/ non-detectionand presence/ absence data using camera traps and road strip counts.Usinga single season, single species occupancy framework as a surrogate for habitat usewedeterminedhow transformed landscapes affected their occupancy. Using aniche factor analysis and resource selection functions wedetermine how transformed landscapes affected the resource selectionof these species. Our results from the resource selection analysis indicated that steenbok, grey rhebok, andcommon duiker included crops such as wheat and planted pastures in their resource selection while also including natural vegetation. Cape grysbok and bushbuck selected predominantly for natural vegetation areas such as critical biodiversity areas and ecological support areas while also including some crops in their resource selection. Our results from the occupancy analysis indicatedthat steenbok, grey rhebok and common duiker had a higher occupancy in the transformed landscape than in the natural landscape. Bushbuck and Cape grysbok showed little to no difference in their occupancy between land use types. The insight provided by our results will allow practitioners to maximise the potentialof these mosaic landscape in the Overberg for mammal conservation.The study also provides a baseline from which further research and monitoring programs can be developed to further understand the dynamics of this landscape. , Thesis (MSc) -- Faculty of Science, School of Natural Resource Management, 2021
- Full Text:
- Date Issued: 2021-12
A conceptual IT governance framework to guide the development of interoperable health information systems
- Authors: Matshaba, Lebogang
- Date: 2022-04-06
- Subjects: Information technology Management , Information technology Management Standards , Information technology Security measures , Medical informatics South Africa , Medical records Data processing , Internetworking (Telecommunication) , National health insurance South Africa , Design Science Research (DSR)
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/284570 , vital:56075
- Description: In light of changing health needs, health information systems are presented with a plethora of challenges. For instance, the rise of COVID-19 in the past year has led to the discourse on the strength of current health systems to support health needs and the readiness for the National Health Insurance in South Africa. In addition to operating in resource-constrained environments, the lack of synchrony between health information systems across health facilities led to the fragmentation of health information and diminished access to quality healthcare. This research, following the Design Science Research Methodology (DSRM) process, developed an IT governance conceptual framework (HISIG-CF), to inform the interoperability of health information systems. The HISIG-CF is developed from literature and qualitative data collected using an expert reviews method from practitioners in the healthcare sector who evaluated the constructs of the HISIG-CF. Thematic analysis and hermeneutics were used to analyse and interpret the data. The results revealed a need for more guidance to inform interoperability interventions and strengthen current health information systems. The contribution of this study is the HISIG-CF which is deemed relevant and potentially fit-for-purpose to improve health information systems interoperability within the healthcare sector in South Africa. , Thesis (MCom) -- Faculty of Commerce, Department of Information Systems, 2022
- Full Text:
- Date Issued: 2022-04-06
- Authors: Matshaba, Lebogang
- Date: 2022-04-06
- Subjects: Information technology Management , Information technology Management Standards , Information technology Security measures , Medical informatics South Africa , Medical records Data processing , Internetworking (Telecommunication) , National health insurance South Africa , Design Science Research (DSR)
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/284570 , vital:56075
- Description: In light of changing health needs, health information systems are presented with a plethora of challenges. For instance, the rise of COVID-19 in the past year has led to the discourse on the strength of current health systems to support health needs and the readiness for the National Health Insurance in South Africa. In addition to operating in resource-constrained environments, the lack of synchrony between health information systems across health facilities led to the fragmentation of health information and diminished access to quality healthcare. This research, following the Design Science Research Methodology (DSRM) process, developed an IT governance conceptual framework (HISIG-CF), to inform the interoperability of health information systems. The HISIG-CF is developed from literature and qualitative data collected using an expert reviews method from practitioners in the healthcare sector who evaluated the constructs of the HISIG-CF. Thematic analysis and hermeneutics were used to analyse and interpret the data. The results revealed a need for more guidance to inform interoperability interventions and strengthen current health information systems. The contribution of this study is the HISIG-CF which is deemed relevant and potentially fit-for-purpose to improve health information systems interoperability within the healthcare sector in South Africa. , Thesis (MCom) -- Faculty of Commerce, Department of Information Systems, 2022
- Full Text:
- Date Issued: 2022-04-06
Encouraging and discouraging factors to crime reporting in South Africa: a survey of residents’ crime reporting behaviour in Mthatha South Africa police service precinct
- Mbewu, Ithandile, Obioha, Emeka E, Mugari , Ishmael
- Authors: Mbewu, Ithandile , Obioha, Emeka E , Mugari , Ishmael
- Date: 2021
- Subjects: Crime Citizen crime reporting Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6967 , vital:52622 , xlink:href="https://doi.org/10.1080/23311886.2021.2002542"
- Description: The aim of this study was to explore issues concerning dispositions of crime-reporting behaviour of both witnesses and victims and comes against a backdrop of a rise in crime levels in South Africa. The study specifically examined the discouraging and encouraging factors for crime reporting in Mthatha area in the Eastern Cape Province of South Africa. A quantitative methodology was adopted, wherein a closed-ended questionnaire was used to gather data from 120 respondents. The result of the analysis revealed police absence of loyalty to citizens, lack of support for victims and lack of follow-up on reported cases as the major factors which discourage citizens from reporting crimes to the police. Further regression analysis confirmed gender, race, location of respondents and socio-economic status as significant predictors that influence discouragement. As regards the encouraging factors, overall, the citizens’ collective responsibility for safe communities was viewed as the major drive for reporting crimes to the police. From the findings, it can be concluded that poor police-public relations is the main driver for non-reporting of crime. The study recommends strengthening of police-public relations in order to encourage citizens to report crime.
- Full Text:
- Date Issued: 2021
- Authors: Mbewu, Ithandile , Obioha, Emeka E , Mugari , Ishmael
- Date: 2021
- Subjects: Crime Citizen crime reporting Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/6967 , vital:52622 , xlink:href="https://doi.org/10.1080/23311886.2021.2002542"
- Description: The aim of this study was to explore issues concerning dispositions of crime-reporting behaviour of both witnesses and victims and comes against a backdrop of a rise in crime levels in South Africa. The study specifically examined the discouraging and encouraging factors for crime reporting in Mthatha area in the Eastern Cape Province of South Africa. A quantitative methodology was adopted, wherein a closed-ended questionnaire was used to gather data from 120 respondents. The result of the analysis revealed police absence of loyalty to citizens, lack of support for victims and lack of follow-up on reported cases as the major factors which discourage citizens from reporting crimes to the police. Further regression analysis confirmed gender, race, location of respondents and socio-economic status as significant predictors that influence discouragement. As regards the encouraging factors, overall, the citizens’ collective responsibility for safe communities was viewed as the major drive for reporting crimes to the police. From the findings, it can be concluded that poor police-public relations is the main driver for non-reporting of crime. The study recommends strengthening of police-public relations in order to encourage citizens to report crime.
- Full Text:
- Date Issued: 2021
An analysis of inland fisheries resource use in the Eastern Cape, South Africa
- Authors: Matam, Ncumisa Yanga
- Date: 2022-10-14
- Subjects: Fisheries South Africa Eastern Cape , Fishery law and legislation South Africa Eastern Cape , Small-scale fisheries South Africa Eastern Cape , Small-scale fisheries Social aspects South Africa Eastern Cape , Small-scale fisheries Economic aspects South Africa Eastern Cape , SADC Inland Fisheries Sector , Subsistence fishing South Africa Eastern Cape , Draft Inland Fisheries Policy (South Africa)
- Language: English
- Type: Master's thesis , text
- Identifier: http://hdl.handle.net/10962/232215 , vital:49972
- Description: South Africa’s Draft Inland Fisheries Policy identifies inland fisheries as an opportunity for socio-economic benefits such as jobs, food security and economic development, based on small-scale fishing and recreational value chains. Using roving creel surveys, this study examined various fishing groups in publicly accessible dams in both an urban and a rural settlement in the Makana Municipal area, Eastern Cape, South Africa. While inland fisheries are particularly relevant for rural communities, there is very little information on the current use of these resources, irrespective of inland fisheries’ importance. This thesis presents a conceptual framework for a study that: (1) reviews available information of inland fisheries and development attempts in South Africa; (2) provides an assessment of the use of inland fisheries on publicly accessible dams in the Makana Municipal area and (3) evaluates case studies of current and past utilization of selected inland fisheries initiatives in the Eastern Cape. The results of this project provide insights into the current conditions and development potentials of inland fisheries in the Eastern Cape. There was a difference in species composition between the dams, but no difference in the CPUE between dams. For example, in Grey dam many species were present, but as the dam size is only one hectare, this would result in an estimated yield harvest of only 207 kg/ha/year. Anglers were encountered at all dams, although fish were only retrieved by anglers in the rural dams of Committees Drift. Dam usage in the rural area was mostly subsistence angling, and this was significantly greater than in the urban area. Subsistence fishers utilised the fish to sustain themselves and their families and for better livelihoods. Anglers from outside the area tended to utilise the dam for recreational angling. Dams found in the urban area were also mostly used by subsistence anglers, though there were a few uses for aesthetic purposes. The urban dams were also utilised recreationally (picnics, year-end functions, swimming), as opposed to the rural dams which were only used for angling. A total of 10 interviews were administered to key respondents in the form of a questionnaires to determine the importance of the fisheries to them. Catch documented from the questionnaires, interviews and logbooks constituted 1238 species and 978 020 kg. Of all the anglers encountered from the interviews, the gill net catch species varied by dam. The fate of fish caught by anglers was dependent on employment status, with most unemployed anglers selling their fish for income and most employed anglers consuming their catch. The findings show that dams were used mostly by small-scale fishers and recreational anglers. Ichthyological surveys revealed that popular fish harvested were moggel, common carp, largemouth bass and Mozambique tilapia. The results are discussed in the context of appropriate development of fisheries in small dams in the province, with recommendations to continue monitored surveys to better inform the inland fisheries policy. The findings from this thesis show that having small scale fisheries in place and providing good access to the dams is essential for rural populations, in turn, providing better livelihoods through hunger alleviation and generating household income. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Matam, Ncumisa Yanga
- Date: 2022-10-14
- Subjects: Fisheries South Africa Eastern Cape , Fishery law and legislation South Africa Eastern Cape , Small-scale fisheries South Africa Eastern Cape , Small-scale fisheries Social aspects South Africa Eastern Cape , Small-scale fisheries Economic aspects South Africa Eastern Cape , SADC Inland Fisheries Sector , Subsistence fishing South Africa Eastern Cape , Draft Inland Fisheries Policy (South Africa)
- Language: English
- Type: Master's thesis , text
- Identifier: http://hdl.handle.net/10962/232215 , vital:49972
- Description: South Africa’s Draft Inland Fisheries Policy identifies inland fisheries as an opportunity for socio-economic benefits such as jobs, food security and economic development, based on small-scale fishing and recreational value chains. Using roving creel surveys, this study examined various fishing groups in publicly accessible dams in both an urban and a rural settlement in the Makana Municipal area, Eastern Cape, South Africa. While inland fisheries are particularly relevant for rural communities, there is very little information on the current use of these resources, irrespective of inland fisheries’ importance. This thesis presents a conceptual framework for a study that: (1) reviews available information of inland fisheries and development attempts in South Africa; (2) provides an assessment of the use of inland fisheries on publicly accessible dams in the Makana Municipal area and (3) evaluates case studies of current and past utilization of selected inland fisheries initiatives in the Eastern Cape. The results of this project provide insights into the current conditions and development potentials of inland fisheries in the Eastern Cape. There was a difference in species composition between the dams, but no difference in the CPUE between dams. For example, in Grey dam many species were present, but as the dam size is only one hectare, this would result in an estimated yield harvest of only 207 kg/ha/year. Anglers were encountered at all dams, although fish were only retrieved by anglers in the rural dams of Committees Drift. Dam usage in the rural area was mostly subsistence angling, and this was significantly greater than in the urban area. Subsistence fishers utilised the fish to sustain themselves and their families and for better livelihoods. Anglers from outside the area tended to utilise the dam for recreational angling. Dams found in the urban area were also mostly used by subsistence anglers, though there were a few uses for aesthetic purposes. The urban dams were also utilised recreationally (picnics, year-end functions, swimming), as opposed to the rural dams which were only used for angling. A total of 10 interviews were administered to key respondents in the form of a questionnaires to determine the importance of the fisheries to them. Catch documented from the questionnaires, interviews and logbooks constituted 1238 species and 978 020 kg. Of all the anglers encountered from the interviews, the gill net catch species varied by dam. The fate of fish caught by anglers was dependent on employment status, with most unemployed anglers selling their fish for income and most employed anglers consuming their catch. The findings show that dams were used mostly by small-scale fishers and recreational anglers. Ichthyological surveys revealed that popular fish harvested were moggel, common carp, largemouth bass and Mozambique tilapia. The results are discussed in the context of appropriate development of fisheries in small dams in the province, with recommendations to continue monitored surveys to better inform the inland fisheries policy. The findings from this thesis show that having small scale fisheries in place and providing good access to the dams is essential for rural populations, in turn, providing better livelihoods through hunger alleviation and generating household income. , Thesis (MSc) -- Faculty of Science, Environmental Science, 2022
- Full Text:
- Date Issued: 2022-10-14
Diski 9 Nine and Other Stories (and Things)
- Authors: Mahlabe, Stoffel Seshia
- Date: 2022-04-07
- Subjects: Creative writing (Higher education) South Africa , Diaries -- Authorship , South African essays (English) 21st century , Short stories, South African (English) 21st century , Portuguese fiction History and criticism , African literature (English) History and criticism , Ghanaian fiction (English) History and criticism , South African fiction (English) History and criticism
- Language: English
- Type: Master's thesis , text
- Identifier: http://hdl.handle.net/10962/232283 , vital:49978
- Description: My thesis is a collection of short stories that reflects the everyday lives of ordinary people. They touch on issues of morality within the current context, in such a way as to both entertain and educate. As a child I learned to imitate the wildly comical, sometimes dark dinoonwane and dithamalakwane stories I heard from elders. In my thesis, I draw on Amos Tutuola’s exuberant style of retelling Yoruba folktales and balance this with the languid candour of Jose Saramago’s Blindness. Stories such as Bessora’s The Milka Cow, and Micah Dean Hicks’s Crawfish Noon have impressed me deeply for their incredible, wild narrative strategies that still, however, emulate realism. Dambudzo Marechera and Can Themba are also present influences. Both have sprinklings of erudition in their writing, but in an earthy kind of way. Their writing contains transliterations that have a ring of the vernacular languages, an idiom that Africanises the English language. , Thesis (MA) -- Faculty of Humanities, School of Languages, 2022
- Full Text:
- Date Issued: 2022-04-07
- Authors: Mahlabe, Stoffel Seshia
- Date: 2022-04-07
- Subjects: Creative writing (Higher education) South Africa , Diaries -- Authorship , South African essays (English) 21st century , Short stories, South African (English) 21st century , Portuguese fiction History and criticism , African literature (English) History and criticism , Ghanaian fiction (English) History and criticism , South African fiction (English) History and criticism
- Language: English
- Type: Master's thesis , text
- Identifier: http://hdl.handle.net/10962/232283 , vital:49978
- Description: My thesis is a collection of short stories that reflects the everyday lives of ordinary people. They touch on issues of morality within the current context, in such a way as to both entertain and educate. As a child I learned to imitate the wildly comical, sometimes dark dinoonwane and dithamalakwane stories I heard from elders. In my thesis, I draw on Amos Tutuola’s exuberant style of retelling Yoruba folktales and balance this with the languid candour of Jose Saramago’s Blindness. Stories such as Bessora’s The Milka Cow, and Micah Dean Hicks’s Crawfish Noon have impressed me deeply for their incredible, wild narrative strategies that still, however, emulate realism. Dambudzo Marechera and Can Themba are also present influences. Both have sprinklings of erudition in their writing, but in an earthy kind of way. Their writing contains transliterations that have a ring of the vernacular languages, an idiom that Africanises the English language. , Thesis (MA) -- Faculty of Humanities, School of Languages, 2022
- Full Text:
- Date Issued: 2022-04-07
Factors influencing first-year students’ career decisions to pursue an IT career
- Authors: Twani, Malibongwe
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54135 , vital:46306
- Description: The process of deciding on a career is a dauntingand life-changing decision,which all scholarshave had to make. Various factors influence a first-year student’s career choice decision and selected field of study. Career decision-making,as a field of study, has been extensivelyresearched,globally. The research studies focusingon IT career choicesof studentshave indicated that scholars choosing careers in Information Technology (IT) are influenced by factors such as salaries, knowledge of career opportunities, the reputation of IT-related fields in society and by parents, teachers and role models. Recent research indicates that exposure to new technologies and programming concepts at the school level can influence a scholar’s IT career choice. Theories relating to career choice have focused on the characteristics of individuals and their environment. Career choice models have identified factors that influenced a student’s career choice.In South Africahowever,there have been limited studies investigating the factors influencing students’ career decisions in choosing careers in Computer Science (CS), Information Systems (IS) and Information Technology (IT)using mixed-methods.This study aims to investigate the factors that influence first-year students’ decisionsin choosing an IT career at the Nelson Mandela University.The research study pursueda pragmatisticapproach,using a mixed-methods approach. In investigating theories andfactors that influence students’ decisionsin choosing IT careers,the study used systematic literature reviews. The decision-making theories and factorsin theliterature review facilitated the creation of the conceptual framework for IT career decision making. A questionnaire was developed and distributed amongst ITand Non-ITfirst-year studentsin 2021. Fourhundredand eightparticipants completed the survey. The data obtained from the survey were statistically analysed, includingdescriptive analysis andExploratory Factor Analysis(EFA). Additionally, inferential statistics were used namely; Correlations, t-test, Confirmatory Factor Analysis(CFA)and Structural Equation Modelling(SEM). The study results wereinterpreted andcompared with iiiotherrelevantstudies. Recommendations were madeto address the factorsthat influencefirst-year students’ IT career decisions.The study highlighted that high academic confidence and personal attributes amongststudents,whowereinvolved at an early age in programming and using computers,chose IT as a career. The study showed significant statistical differences betweenIT and Non-IT groups in perceptions about the IT industry and identifying job title descriptions.Additionally, a significant statistical difference between languages and genders was identified in understanding careers. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Twani, Malibongwe
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/54135 , vital:46306
- Description: The process of deciding on a career is a dauntingand life-changing decision,which all scholarshave had to make. Various factors influence a first-year student’s career choice decision and selected field of study. Career decision-making,as a field of study, has been extensivelyresearched,globally. The research studies focusingon IT career choicesof studentshave indicated that scholars choosing careers in Information Technology (IT) are influenced by factors such as salaries, knowledge of career opportunities, the reputation of IT-related fields in society and by parents, teachers and role models. Recent research indicates that exposure to new technologies and programming concepts at the school level can influence a scholar’s IT career choice. Theories relating to career choice have focused on the characteristics of individuals and their environment. Career choice models have identified factors that influenced a student’s career choice.In South Africahowever,there have been limited studies investigating the factors influencing students’ career decisions in choosing careers in Computer Science (CS), Information Systems (IS) and Information Technology (IT)using mixed-methods.This study aims to investigate the factors that influence first-year students’ decisionsin choosing an IT career at the Nelson Mandela University.The research study pursueda pragmatisticapproach,using a mixed-methods approach. In investigating theories andfactors that influence students’ decisionsin choosing IT careers,the study used systematic literature reviews. The decision-making theories and factorsin theliterature review facilitated the creation of the conceptual framework for IT career decision making. A questionnaire was developed and distributed amongst ITand Non-ITfirst-year studentsin 2021. Fourhundredand eightparticipants completed the survey. The data obtained from the survey were statistically analysed, includingdescriptive analysis andExploratory Factor Analysis(EFA). Additionally, inferential statistics were used namely; Correlations, t-test, Confirmatory Factor Analysis(CFA)and Structural Equation Modelling(SEM). The study results wereinterpreted andcompared with iiiotherrelevantstudies. Recommendations were madeto address the factorsthat influencefirst-year students’ IT career decisions.The study highlighted that high academic confidence and personal attributes amongststudents,whowereinvolved at an early age in programming and using computers,chose IT as a career. The study showed significant statistical differences betweenIT and Non-IT groups in perceptions about the IT industry and identifying job title descriptions.Additionally, a significant statistical difference between languages and genders was identified in understanding careers. , Thesis (MSc) -- Faculty of Science, School of Computer Science, Mathematics, Physics and Statistics, 2021
- Full Text:
- Date Issued: 2021-12
Orthographic knowledge in isiXhosa and its relation to phonological processing, letter-sound knowledge, reading and spelling
- Authors: Daries, Mikaela Ann
- Date: 2022-10-14
- Subjects: Xhosa language Orthography and spelling , Phonological awareness , Psycholinguistics , Oral reading Usage , Literacy South Africa , Reading Phonetic method
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406703 , vital:70300
- Description: Despite international research confirming its importance, writing and related metalinguistic skills have often been neglected in comparison to reading in literacy research (Cunningham et al., 2001; Castles & Coltheart, 2004; Nag, 2007; Roman et al., 2009; Zhao et al., 2017). On a national level there are very few studies that have explored the writing aspect of literacy in South Africa, and none that has investigated orthographic knowledge in a Southern Bantu language, such as isiXhosa. In an attempt to address this gap, this thesis explores orthographic knowledge and its components in isiXhosa. In particular, it seeks to investigate the unique predictors of word specific and general orthographic knowledge as well as their role for reading and spelling in isiXhosa while controlling for phonological awareness (PA), rapid automatized naming (RAN), and letter-sound knowledge. Furthermore, the thesis attempts to situate its findings within the main premises of the self-teaching hypothesis and dual route approach to orthographic processing in order to contribute to linguistic theories of reading with cross-linguistic evidence (Jorm & Share, 1983; Share & Jorm, 1987; Share, 1995; Grainger & Ziegler, 2011). A quantitative cross-sectional study was conducted with 140 isiXhosa home language third grade learners in which word specific and general orthographic knowledge tasks were specifically designed. These tasks were administered along with oral reading fluency (ORF), spelling, PA, RAN, and letter-sound knowledge. The findings revealed that letter-sound knowledge and PA contributed the largest variance towards both word specific and general orthographic knowledge. Further, word specific orthographic knowledge and letter-sound knowledge were the only significant predictors of spelling. Similarly, both word specific and letter-sound knowledge were significant predictors of reading, along with RAN and general orthographic knowledge. Quantile linear regression analyses revealed that word specific orthographic knowledge was a robust predictor of spelling and letter-sound knowledge was a robust predictor of reading across ability levels confirming the importance for word specific orthographic knowledge for spelling and letter-sound knowledge for reading in isiXhosa. In relation to the two reading theories considered in this thesis, the findings reflect similarities between the assertions of the self-teaching hypothesis and current thesis with suggestions made for further inquiry. The dual route approach to orthographic processing provides insights into the potential processing of orthographic information while reading in isiXhosa. The findings of this study confirm the importance of orthographic knowledge for reading and spelling for languages with transparent orthographies such as isiXhosa. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2022
- Full Text:
- Date Issued: 2022-10-14
- Authors: Daries, Mikaela Ann
- Date: 2022-10-14
- Subjects: Xhosa language Orthography and spelling , Phonological awareness , Psycholinguistics , Oral reading Usage , Literacy South Africa , Reading Phonetic method
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/406703 , vital:70300
- Description: Despite international research confirming its importance, writing and related metalinguistic skills have often been neglected in comparison to reading in literacy research (Cunningham et al., 2001; Castles & Coltheart, 2004; Nag, 2007; Roman et al., 2009; Zhao et al., 2017). On a national level there are very few studies that have explored the writing aspect of literacy in South Africa, and none that has investigated orthographic knowledge in a Southern Bantu language, such as isiXhosa. In an attempt to address this gap, this thesis explores orthographic knowledge and its components in isiXhosa. In particular, it seeks to investigate the unique predictors of word specific and general orthographic knowledge as well as their role for reading and spelling in isiXhosa while controlling for phonological awareness (PA), rapid automatized naming (RAN), and letter-sound knowledge. Furthermore, the thesis attempts to situate its findings within the main premises of the self-teaching hypothesis and dual route approach to orthographic processing in order to contribute to linguistic theories of reading with cross-linguistic evidence (Jorm & Share, 1983; Share & Jorm, 1987; Share, 1995; Grainger & Ziegler, 2011). A quantitative cross-sectional study was conducted with 140 isiXhosa home language third grade learners in which word specific and general orthographic knowledge tasks were specifically designed. These tasks were administered along with oral reading fluency (ORF), spelling, PA, RAN, and letter-sound knowledge. The findings revealed that letter-sound knowledge and PA contributed the largest variance towards both word specific and general orthographic knowledge. Further, word specific orthographic knowledge and letter-sound knowledge were the only significant predictors of spelling. Similarly, both word specific and letter-sound knowledge were significant predictors of reading, along with RAN and general orthographic knowledge. Quantile linear regression analyses revealed that word specific orthographic knowledge was a robust predictor of spelling and letter-sound knowledge was a robust predictor of reading across ability levels confirming the importance for word specific orthographic knowledge for spelling and letter-sound knowledge for reading in isiXhosa. In relation to the two reading theories considered in this thesis, the findings reflect similarities between the assertions of the self-teaching hypothesis and current thesis with suggestions made for further inquiry. The dual route approach to orthographic processing provides insights into the potential processing of orthographic information while reading in isiXhosa. The findings of this study confirm the importance of orthographic knowledge for reading and spelling for languages with transparent orthographies such as isiXhosa. , Thesis (MA) -- Faculty of Humanities, Linguistics and Applied Language Studies, 2022
- Full Text:
- Date Issued: 2022-10-14
Quantifying the impacts of cactus biological control agents in South Africa
- Authors: Mnqeta, Zezethu
- Date: 2022-04-08
- Subjects: Cactus Biological control South Africa , Noxious weeds South Africa , Invasive plants Biological control South Africa , Insects as biological pest control agents South Africa , Cochineal insect South Africa , Mealybugs South Africa , Agricultural productivity South Africa
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/294631 , vital:57239 , DOI 10.21504/10962/294631
- Description: Invasive alien cacti are prominent weeds that threaten indigenous biodiversity and have a negative impact on agricultural productivity in South Africa. These plants are problematic because they form dense thickets that reduce the carrying capacity of rangelands; restrict the movement of livestock and wildlife thus reducing access to shade and water sources; and are directly harmful to livestock, wildlife and people due to their sharp spines. Biological control is the most effective, affordable and environmentally friendly method to control invasive alien cacti and minimize their negative impacts. Cochineal insects (Dactylopius spp.: Dactylopiidae) and the gall-forming mealybug, Hypogeococcus sp. (Pseudococcidae) are used as biological control agents for cacti. The agents are however poor dispersers, so mass-rearing and augmentative releases are required in order to establish the agents at sites where they are needed. This study aimed to evaluate the mass-rearing and release efforts of cactus biological control in South Africa, quantify the impact of the biological control agents on cactus plant populations through long-term monitoring, and assess the benefits accrued due to the biological control agents through the perceptions of land-users. An assessment of the effectiveness of the release effort for cactus biological control agents was conducted by comparing where biological control agents have been released with the known distribution of the target weeds. Only 26% of the quarter degree squares that are known to be occupied by invasive alien cacti have had biological control agents released in them. This indicated that the mass-rearing and release efforts in South Africa are inadequate and should be increased, especially in areas where few releases have been made and many cacti are present, such as the Limpopo Province. The impact of the biological control agents on cactus plant populations was assessed by monitoring agent densities, target plant densities and target plant reproductive outputs before and after releases. Plant biomass and reproductive output were reduced by biological control agents for three of the target weeds that were assessed, while the duration of the study was too short to measure reductions for the fourth target weed. Benefits to land-users were then quantified through a questionnaire survey. Land-users perceived biological control as an effective management option, with 81% of the land-users reporting that there was less invasive alien cactus after releasing biological control agents on their land. Forty-nine percent of the land-users believed that the negative impacts of the cactus had been reduced and that they benefited more from their land since control was achieved. Since land-users were only interviewed within four years of the releases being conducted, it is expected that the percentage of land-users who gained benefits from biological control will increase in future. Ninety-seven percent of the land-users stated that the agents were safe and had not fed on any other plants or had any detrimental impacts. These perceptions indicated that land-users regarded biological control as a safe and effective method of controlling invasive alien cacti. This study confirms that biological control is an effective and safe way of controlling invasive alien Cactaceae. It is also the first to assess some of the benefits that land-users have accrued due to biological control of cactus weeds. It is however evident that a greater mass-rearing and release effort is required for South Africa to get the maximum benefits possible from the use of the biological control agents for cactus weeds that are available in the country. , Izityalo ze-cactus ezisuka kwamanye amazwe zilukhula olubalaseleyo, olwenza ingxaki kwintlobo ngeentlobo zezityalo nezilwanyana kwaye ezizityalo zinefuthe neziphumo ezingalunganga kwimveliso yezolimo eMzantsi Afrika. Ezi zizityalo ziyingxaki kuba zenza amatyholo ashinyeneyo athi anciphise umthamo wokusebenzisa umhlaba: zinqanda ukuhamba nogkukhululekileyo kwemfuyo nezilwanyana zasendle ngokwenza oko zingakwazi ukufikelela emthuzini xa kutshisa nakwimithombo yamanzi yokusela; zikwayiyo nengozi kwimfuyo, izilwanyana zasendle kunye nabantu ngenxa yamave abukhali afumaneka kwezizityalo. Ukulawula nokwehliza ubunzini nezinga lemigcipheko yezizityalo, kusetyenziswa indlela ekuthiwa yi-biological control. Lendlela yeyona ndlela isebenza ngokuphucukileyo, efikelelayo, nengenabungozi kokusingqongileyo. Izinambuzane ze- cochineal (i-Dactylopius spp.: Dactylopiidae) kunye ne-mealybug, i-Hypogeococcus sp. (Pseudococcidae) zisetyenziswe njengezixhobo ze-biological control ezinceda ukulawula ezizityalo ze-cactus zingafunekiyo. Ingxaki yazo ezizinambuzane zizixhobo ze-biological control zingentla kukuba azikwazi kuzisasaza ngokwazo ukuba zifikelele nakwizityalo ezikude ngoko ke ukukhuliswa nokukhutshwa ngobuninzi bazo kuyafuneka ukukhawulelana nalengxaki kunye nokwandisa amathuba wokuba zifikelele kuzozonke izityalo ze-cactus ekufuneka zizilawule. Olu phononongo lujolise ekuvavanyeni iinzame zokukhulisa ngobuninzi nokukhupha ezezinambuzane zizixhobo ze-bioloigical control zokulawula izityalo ze-cactus eMzantsi Afrika, ukujonga ubungakanani befuthe notshintsho elenziwa zezinambuzane zizixhobo ze-bioloigical control kwizityalo ze-cactus emva kwexesha elide lokuzijonga, kunye nokuvavanya inzuzo efunyenwe ngenxa yokulawula ezizityalo ze-cactus ngokwemibono yabasebenzisi bomhlaba. Uvavanyo lweenzame zokukhutshwa kwezixhobo zezixhobo zezinambuzane ze-bioloigical control kwizityalo ze-cactus lwenziwa ngokuthelekisa iindawo apho izixhobo zezinambuzane ze-biological control zikhutshwe khona kunye neendawo apho izityalo ze-cactus kwaziwayo ukuba ziyafumaneka khona. Yi-26% kuphela yesikwere sekota eyaziwayo ukuba kukhona izityalo ze-cactus nalapho kukhutshwe khona kwezinambuzane ezizixhobo ze-biological control. Oku kubonisa ukuba iinzame zokukhulisa nokukhutshwa kwezinambuzane ezizixhobo ze-biological control eMzantsi Afrika azanelanga kwaye kufuneka zandiswe, ngakumbi kwiindawo apho kukho ukhutsho olumbalwa olwenziweyo kunye nezityalo ze-cactus ezininzi ezifumaneka khona, njengePhondo laseLimpopo. Iimpembelelo yokukhutshwa kwezinambuzane ezizixhobo ze-biological control kwizityalo ze-cactus zavavanywa ngokujonga ubunizi bezinambuzane ezizixhobo ze-biological control, ukuxinana kwezityalo ze-cactus ekujoliswe kuzo kunye nemveliso yokuzala kwezityalo ze-cactus phambi nasemva kokuba kukhutshwe izinambuzane ezizixhobo ze-biological control. Ubungakanani bezityalo ze-cactus kunye nemveliso yokuzala ziye zacutheka emva kokukhutshwa kwezinambuzane ezizixhobo ze-biological control kwinzityalo ezintathu ze-cactus ebekujoliswe uvavanyo kuzo, ngelixa ixesha lophononongo lalifutshane kakhulu ukuvavanya unciphiso kwisityalo se-cactus sesine. Izibonelelo zabasebenzisi bomhlaba zaye zavavanywa kusetyenziswa uhlobo lwemibuzo. Abasebenzisi bomhlaba balubona ukusetyenziswa kwezinambuzane ezizixhobo ze-biological control njengendlela yolawulo olusebenzayo, yi81% yabasebenzisi bomhlaba echaze ukuba izityalo ze-cactus zecuthekile emva kokukhutshwa kwezinambuzane ezizixhobo ze-biological control emhlabeni wabo. Amashumi amane anesithoba eepesenti zabasebenzisi bomhlaba bakholelwa ukuba impembelelo ezingalunganga ze-cactus zincitshisiwe kwaye baxhamle kakhulu kumhlaba wabo okoko lwaphunyenzwa. Oludliwano-ndlebe belwenziwe kubasebenzisi bomhlaba kwisithuba seminyaka emine emva kokuba kukhutshwe izinambuzane ezizixhobo ze-biological control, kulindeleke ukuba ipesenti yabasebenzisi bomhlaba abathe bafumana izibonelelo kwi-biological control lonyuke kwixesha elizayo. Amashumi alithoba anesixhenxe ekhulwini abasebenzisi bomhlaba bachaze ukuba izinambuzane ezizixhobo ze-biological control zikhuselekile kwaye khange zidle kuzo naziphi na ezinye izityalo ezingezi eze-cactus ebekujoliswe kuzo okanye zineempembelelo eyingozi. Ezi mbono ziyabonisa ukuba abasebenzi bomhlaba bayithatha i-biological control njengendlela ekhuselekileyo nesebenzayo yokulawula izityalo ze-cactus zamanye amazwe. Olu phononongo luqinisekisa ukuba ulawulo olusebenzisa izinambuzane ezizixhobo ze-biological control yindlela esebenzayo nekhuselekileyo yokulawula iCactaceae yamanye amazwe. Ikwangolokuqala ukuvavanya ezinye zezibonelelo ezizuzwe ngabasebenzisi bomhlaba ngenxa ye-biological control yezityalo ze-cactus. Nangona kunjalo kucacile ukuba ukwandisa inzame zokukhulisa nokukhupha ngobuninzi izinambuzane ezizixhobo ze-biological control kuyafuneka ukuze uMzantsi Afrika ufumane izibonelelo eziphakamileyo enokubakho ngokusetyenziswa kwe zinambuzane ezizixhobo ze-biological control zokulawula ukhula lwe-cactus olukhoyo kweli lizwe. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2022
- Full Text:
- Date Issued: 2022-04-08
- Authors: Mnqeta, Zezethu
- Date: 2022-04-08
- Subjects: Cactus Biological control South Africa , Noxious weeds South Africa , Invasive plants Biological control South Africa , Insects as biological pest control agents South Africa , Cochineal insect South Africa , Mealybugs South Africa , Agricultural productivity South Africa
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/294631 , vital:57239 , DOI 10.21504/10962/294631
- Description: Invasive alien cacti are prominent weeds that threaten indigenous biodiversity and have a negative impact on agricultural productivity in South Africa. These plants are problematic because they form dense thickets that reduce the carrying capacity of rangelands; restrict the movement of livestock and wildlife thus reducing access to shade and water sources; and are directly harmful to livestock, wildlife and people due to their sharp spines. Biological control is the most effective, affordable and environmentally friendly method to control invasive alien cacti and minimize their negative impacts. Cochineal insects (Dactylopius spp.: Dactylopiidae) and the gall-forming mealybug, Hypogeococcus sp. (Pseudococcidae) are used as biological control agents for cacti. The agents are however poor dispersers, so mass-rearing and augmentative releases are required in order to establish the agents at sites where they are needed. This study aimed to evaluate the mass-rearing and release efforts of cactus biological control in South Africa, quantify the impact of the biological control agents on cactus plant populations through long-term monitoring, and assess the benefits accrued due to the biological control agents through the perceptions of land-users. An assessment of the effectiveness of the release effort for cactus biological control agents was conducted by comparing where biological control agents have been released with the known distribution of the target weeds. Only 26% of the quarter degree squares that are known to be occupied by invasive alien cacti have had biological control agents released in them. This indicated that the mass-rearing and release efforts in South Africa are inadequate and should be increased, especially in areas where few releases have been made and many cacti are present, such as the Limpopo Province. The impact of the biological control agents on cactus plant populations was assessed by monitoring agent densities, target plant densities and target plant reproductive outputs before and after releases. Plant biomass and reproductive output were reduced by biological control agents for three of the target weeds that were assessed, while the duration of the study was too short to measure reductions for the fourth target weed. Benefits to land-users were then quantified through a questionnaire survey. Land-users perceived biological control as an effective management option, with 81% of the land-users reporting that there was less invasive alien cactus after releasing biological control agents on their land. Forty-nine percent of the land-users believed that the negative impacts of the cactus had been reduced and that they benefited more from their land since control was achieved. Since land-users were only interviewed within four years of the releases being conducted, it is expected that the percentage of land-users who gained benefits from biological control will increase in future. Ninety-seven percent of the land-users stated that the agents were safe and had not fed on any other plants or had any detrimental impacts. These perceptions indicated that land-users regarded biological control as a safe and effective method of controlling invasive alien cacti. This study confirms that biological control is an effective and safe way of controlling invasive alien Cactaceae. It is also the first to assess some of the benefits that land-users have accrued due to biological control of cactus weeds. It is however evident that a greater mass-rearing and release effort is required for South Africa to get the maximum benefits possible from the use of the biological control agents for cactus weeds that are available in the country. , Izityalo ze-cactus ezisuka kwamanye amazwe zilukhula olubalaseleyo, olwenza ingxaki kwintlobo ngeentlobo zezityalo nezilwanyana kwaye ezizityalo zinefuthe neziphumo ezingalunganga kwimveliso yezolimo eMzantsi Afrika. Ezi zizityalo ziyingxaki kuba zenza amatyholo ashinyeneyo athi anciphise umthamo wokusebenzisa umhlaba: zinqanda ukuhamba nogkukhululekileyo kwemfuyo nezilwanyana zasendle ngokwenza oko zingakwazi ukufikelela emthuzini xa kutshisa nakwimithombo yamanzi yokusela; zikwayiyo nengozi kwimfuyo, izilwanyana zasendle kunye nabantu ngenxa yamave abukhali afumaneka kwezizityalo. Ukulawula nokwehliza ubunzini nezinga lemigcipheko yezizityalo, kusetyenziswa indlela ekuthiwa yi-biological control. Lendlela yeyona ndlela isebenza ngokuphucukileyo, efikelelayo, nengenabungozi kokusingqongileyo. Izinambuzane ze- cochineal (i-Dactylopius spp.: Dactylopiidae) kunye ne-mealybug, i-Hypogeococcus sp. (Pseudococcidae) zisetyenziswe njengezixhobo ze-biological control ezinceda ukulawula ezizityalo ze-cactus zingafunekiyo. Ingxaki yazo ezizinambuzane zizixhobo ze-biological control zingentla kukuba azikwazi kuzisasaza ngokwazo ukuba zifikelele nakwizityalo ezikude ngoko ke ukukhuliswa nokukhutshwa ngobuninzi bazo kuyafuneka ukukhawulelana nalengxaki kunye nokwandisa amathuba wokuba zifikelele kuzozonke izityalo ze-cactus ekufuneka zizilawule. Olu phononongo lujolise ekuvavanyeni iinzame zokukhulisa ngobuninzi nokukhupha ezezinambuzane zizixhobo ze-bioloigical control zokulawula izityalo ze-cactus eMzantsi Afrika, ukujonga ubungakanani befuthe notshintsho elenziwa zezinambuzane zizixhobo ze-bioloigical control kwizityalo ze-cactus emva kwexesha elide lokuzijonga, kunye nokuvavanya inzuzo efunyenwe ngenxa yokulawula ezizityalo ze-cactus ngokwemibono yabasebenzisi bomhlaba. Uvavanyo lweenzame zokukhutshwa kwezixhobo zezixhobo zezinambuzane ze-bioloigical control kwizityalo ze-cactus lwenziwa ngokuthelekisa iindawo apho izixhobo zezinambuzane ze-biological control zikhutshwe khona kunye neendawo apho izityalo ze-cactus kwaziwayo ukuba ziyafumaneka khona. Yi-26% kuphela yesikwere sekota eyaziwayo ukuba kukhona izityalo ze-cactus nalapho kukhutshwe khona kwezinambuzane ezizixhobo ze-biological control. Oku kubonisa ukuba iinzame zokukhulisa nokukhutshwa kwezinambuzane ezizixhobo ze-biological control eMzantsi Afrika azanelanga kwaye kufuneka zandiswe, ngakumbi kwiindawo apho kukho ukhutsho olumbalwa olwenziweyo kunye nezityalo ze-cactus ezininzi ezifumaneka khona, njengePhondo laseLimpopo. Iimpembelelo yokukhutshwa kwezinambuzane ezizixhobo ze-biological control kwizityalo ze-cactus zavavanywa ngokujonga ubunizi bezinambuzane ezizixhobo ze-biological control, ukuxinana kwezityalo ze-cactus ekujoliswe kuzo kunye nemveliso yokuzala kwezityalo ze-cactus phambi nasemva kokuba kukhutshwe izinambuzane ezizixhobo ze-biological control. Ubungakanani bezityalo ze-cactus kunye nemveliso yokuzala ziye zacutheka emva kokukhutshwa kwezinambuzane ezizixhobo ze-biological control kwinzityalo ezintathu ze-cactus ebekujoliswe uvavanyo kuzo, ngelixa ixesha lophononongo lalifutshane kakhulu ukuvavanya unciphiso kwisityalo se-cactus sesine. Izibonelelo zabasebenzisi bomhlaba zaye zavavanywa kusetyenziswa uhlobo lwemibuzo. Abasebenzisi bomhlaba balubona ukusetyenziswa kwezinambuzane ezizixhobo ze-biological control njengendlela yolawulo olusebenzayo, yi81% yabasebenzisi bomhlaba echaze ukuba izityalo ze-cactus zecuthekile emva kokukhutshwa kwezinambuzane ezizixhobo ze-biological control emhlabeni wabo. Amashumi amane anesithoba eepesenti zabasebenzisi bomhlaba bakholelwa ukuba impembelelo ezingalunganga ze-cactus zincitshisiwe kwaye baxhamle kakhulu kumhlaba wabo okoko lwaphunyenzwa. Oludliwano-ndlebe belwenziwe kubasebenzisi bomhlaba kwisithuba seminyaka emine emva kokuba kukhutshwe izinambuzane ezizixhobo ze-biological control, kulindeleke ukuba ipesenti yabasebenzisi bomhlaba abathe bafumana izibonelelo kwi-biological control lonyuke kwixesha elizayo. Amashumi alithoba anesixhenxe ekhulwini abasebenzisi bomhlaba bachaze ukuba izinambuzane ezizixhobo ze-biological control zikhuselekile kwaye khange zidle kuzo naziphi na ezinye izityalo ezingezi eze-cactus ebekujoliswe kuzo okanye zineempembelelo eyingozi. Ezi mbono ziyabonisa ukuba abasebenzi bomhlaba bayithatha i-biological control njengendlela ekhuselekileyo nesebenzayo yokulawula izityalo ze-cactus zamanye amazwe. Olu phononongo luqinisekisa ukuba ulawulo olusebenzisa izinambuzane ezizixhobo ze-biological control yindlela esebenzayo nekhuselekileyo yokulawula iCactaceae yamanye amazwe. Ikwangolokuqala ukuvavanya ezinye zezibonelelo ezizuzwe ngabasebenzisi bomhlaba ngenxa ye-biological control yezityalo ze-cactus. Nangona kunjalo kucacile ukuba ukwandisa inzame zokukhulisa nokukhupha ngobuninzi izinambuzane ezizixhobo ze-biological control kuyafuneka ukuze uMzantsi Afrika ufumane izibonelelo eziphakamileyo enokubakho ngokusetyenziswa kwe zinambuzane ezizixhobo ze-biological control zokulawula ukhula lwe-cactus olukhoyo kweli lizwe. , Thesis (PhD) -- Faculty of Science, Zoology and Entomology, 2022
- Full Text:
- Date Issued: 2022-04-08
Chinese character learning with the aid of an ICT website among Mandarin Second Additional Language learners in South Africa: a case study
- Authors: Fu, Shuying
- Date: 2022-04-08
- Subjects: Mandarin dialects Study and teaching (Secondary) South Africa , Mandarin dialects Computer-assisted instruction for English speakers , Second language acquisition , Chinese characters , Information technology South Africa , Educational technology South Africa , Arch Chinese
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/263590 , vital:53641
- Description: The teaching of Mandarin as a Second Additional Language (SAL) in South African schools was only introduced in 2016. The year 2018 saw the first Mandarin as SAL National Senior Certificate examination. Little research has been done on the teaching and learning of Mandarin as a SAL subject at the high school level in South Africa. Character learning and teaching are some of the most challenging aspects of this language teaching and learning. This research sought to investigate how beginner Mandarin SAL learners can be supported by a particular Information Communication Technology (ICT) website, www.archchinese.com (Arch Chinese), in their character learning. Learners’ ability to memorise Chinese characters is of utmost importance for their success in this language learning, especially for matriculants. To support the main research goal, this study set out to investigate the requirements for Chinese character learning, the role the website Arch Chinese plays in learners’ character learning and Mandarin SAL learners’ experience of using Arch Chinese as a learning tool. This research was conducted in the form of a case study within the interpretative paradigm. It adopted a questionnaire and document analysis for data collection to gain insight into the research topic. To get answers to the research questions posed above, the study analysed the Curriculum Assessment Policy Statement (CAPS) Mandarin SAL documents from Grade 4–12, the Independent Examination Board (IEB) Mandarin Subject Assessment Guidelines (SAGs), and a textbook for beginners, Learn Chinese with me: Student’s book 1 in relation to character learning. The features and functions of the website, Arch Chinese, were also evaluated and Mandarin SAL learners’ answers to a questionnaire on their use of the website Arch Chinese were analysed. The study found that character teaching and learning has not been given enough attention in the curriculum. It was only covered in the Intermediate Phase but was seldom mentioned in the Senior and Further Education and Training Phases in the curriculum. The CAPS Mandarin SAL documents do not consider the special characteristics of the Mandarin language, as this curriculum was based on the CAPS English Generic SAL document. As a result, the assessment requirements on writing (character count requirement in particular) were not realistic. The teaching approaches promoted in the curriculum and the teaching time do not correspond well with the teaching and learning of this language. Moreover, this study found that there was no vocabulary list prescribed in the curriculum and therefore a gap exists between the curriculum on paper and the curriculum in practice. The analysis of the IEB SAGs found that the assessments were suitable for the level of Mandarin SAL learners. This is because the IEB considered the characteristics of the Mandarin language, which is non-cognate, to the alphabet-based languages that respondents in this research spoke or were familiar with. At the same time, the analysis of the website and the learners’ questionnaire found that learners held a positive attitude towards their use of the website and that it proved to help facilitate Mandarin SAL learners in their character learning. This study ends with recommendations for teachers, policy makers, the IEB, and character-learning websites. , Thesis (MEd) -- Faculty of Education, Education, 2022
- Full Text: false
- Date Issued: 2022-04-08
- Authors: Fu, Shuying
- Date: 2022-04-08
- Subjects: Mandarin dialects Study and teaching (Secondary) South Africa , Mandarin dialects Computer-assisted instruction for English speakers , Second language acquisition , Chinese characters , Information technology South Africa , Educational technology South Africa , Arch Chinese
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/263590 , vital:53641
- Description: The teaching of Mandarin as a Second Additional Language (SAL) in South African schools was only introduced in 2016. The year 2018 saw the first Mandarin as SAL National Senior Certificate examination. Little research has been done on the teaching and learning of Mandarin as a SAL subject at the high school level in South Africa. Character learning and teaching are some of the most challenging aspects of this language teaching and learning. This research sought to investigate how beginner Mandarin SAL learners can be supported by a particular Information Communication Technology (ICT) website, www.archchinese.com (Arch Chinese), in their character learning. Learners’ ability to memorise Chinese characters is of utmost importance for their success in this language learning, especially for matriculants. To support the main research goal, this study set out to investigate the requirements for Chinese character learning, the role the website Arch Chinese plays in learners’ character learning and Mandarin SAL learners’ experience of using Arch Chinese as a learning tool. This research was conducted in the form of a case study within the interpretative paradigm. It adopted a questionnaire and document analysis for data collection to gain insight into the research topic. To get answers to the research questions posed above, the study analysed the Curriculum Assessment Policy Statement (CAPS) Mandarin SAL documents from Grade 4–12, the Independent Examination Board (IEB) Mandarin Subject Assessment Guidelines (SAGs), and a textbook for beginners, Learn Chinese with me: Student’s book 1 in relation to character learning. The features and functions of the website, Arch Chinese, were also evaluated and Mandarin SAL learners’ answers to a questionnaire on their use of the website Arch Chinese were analysed. The study found that character teaching and learning has not been given enough attention in the curriculum. It was only covered in the Intermediate Phase but was seldom mentioned in the Senior and Further Education and Training Phases in the curriculum. The CAPS Mandarin SAL documents do not consider the special characteristics of the Mandarin language, as this curriculum was based on the CAPS English Generic SAL document. As a result, the assessment requirements on writing (character count requirement in particular) were not realistic. The teaching approaches promoted in the curriculum and the teaching time do not correspond well with the teaching and learning of this language. Moreover, this study found that there was no vocabulary list prescribed in the curriculum and therefore a gap exists between the curriculum on paper and the curriculum in practice. The analysis of the IEB SAGs found that the assessments were suitable for the level of Mandarin SAL learners. This is because the IEB considered the characteristics of the Mandarin language, which is non-cognate, to the alphabet-based languages that respondents in this research spoke or were familiar with. At the same time, the analysis of the website and the learners’ questionnaire found that learners held a positive attitude towards their use of the website and that it proved to help facilitate Mandarin SAL learners in their character learning. This study ends with recommendations for teachers, policy makers, the IEB, and character-learning websites. , Thesis (MEd) -- Faculty of Education, Education, 2022
- Full Text: false
- Date Issued: 2022-04-08
Strategies utilised in translating children’s stories from English into isiXhosa
- Authors: Madolo, Yolisa
- Date: 2021
- Subjects: Children Xhosa Grammar, Comparative and general--Ideophone Children, Black, in literature Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7010 , vital:52637 , xlink:href="https://doi.org/10.1080/02572117.2021.2010919"
- Description: Translation scholars suggest various strategies for dealing with equivalence and non-equivalence. These popular strategies address non-equivalence, the converse of equivalence, that is commonly found in translation. Nonequivalence is found at word, phrase, sentence, and pragmatic levels. Not a great deal of research has been done in the translation strategies used between English and South African indigenous languages. It is possible that these languages employ some strategies that are not listed under current, popular strategies. These strategies may be necessitated by the linguistic and historical differences between English and African languages. For instance, what is acceptable in question form in English might be more suitable as a statement in African languages, specifically isiXhosa. The strategies to be presented are from an ongoing study of selected children’s stories translated from English into isiXhosa. The aim of the study is to scrutinise some of the strategies used by the translators in their translations. Preliminary results reveal that translators from English into isiXhosa may explicitate or implicitate the translation using various strategies like addition, infusing target language culture, translating source language idiom by another figure of speech or even omitting some words. This may have minimal or significant impact on the transferred message.
- Full Text:
- Date Issued: 2021
- Authors: Madolo, Yolisa
- Date: 2021
- Subjects: Children Xhosa Grammar, Comparative and general--Ideophone Children, Black, in literature Article
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/11260/7010 , vital:52637 , xlink:href="https://doi.org/10.1080/02572117.2021.2010919"
- Description: Translation scholars suggest various strategies for dealing with equivalence and non-equivalence. These popular strategies address non-equivalence, the converse of equivalence, that is commonly found in translation. Nonequivalence is found at word, phrase, sentence, and pragmatic levels. Not a great deal of research has been done in the translation strategies used between English and South African indigenous languages. It is possible that these languages employ some strategies that are not listed under current, popular strategies. These strategies may be necessitated by the linguistic and historical differences between English and African languages. For instance, what is acceptable in question form in English might be more suitable as a statement in African languages, specifically isiXhosa. The strategies to be presented are from an ongoing study of selected children’s stories translated from English into isiXhosa. The aim of the study is to scrutinise some of the strategies used by the translators in their translations. Preliminary results reveal that translators from English into isiXhosa may explicitate or implicitate the translation using various strategies like addition, infusing target language culture, translating source language idiom by another figure of speech or even omitting some words. This may have minimal or significant impact on the transferred message.
- Full Text:
- Date Issued: 2021
Beneficiation of pyrolysis-derived waste tyre char by blending with torrefied wood and microalgae to produce solid fuel
- Authors: Dube, Cleopatra Thulani
- Date: 2021-12
- Subjects: Pyrolysis , Solid fuel reactors
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58439 , vital:59241
- Description: he thermal decomposition of waste tyres via pyrolysis is considered to be amongst the most promising methods of recycling tyres due to its minimal environmental impact (in terms of reduction in pollution). During pyrolysis, tyres are thermally degraded in an inert environment to produce gas, oil and char. The gas and oil have promising commercialization prospects while the char remains a pollutant despite the strides made in a lot of research to upgrade the char to carbon black, activated carbon and even for reuse as a filler in tyre manufacture. For pyrolysis to be profitable, or worthy of investments, all three of its products (oil, char and gas) need to be valorised. Pyrolysis-derived tyre chars (PT-char) have an energy value equivalent to high rank coals, however, the use of PT char as a solid fuel is uncommon due to the high contents of sulphur and mineral matter as well as low volatile matter content of the PT-char. As such, the combustion of PT-char is characterised by high ignition temperature, low thermal reactivity, and no flame formation due to the low amounts of volatile matter. On the other hand, biomass are clean, renewable feedstock, having low sulphur and mineral matter contents, as well as high thermal reactivity. The blending of PT-char with biomass could potentially improve the combustion properties of PT-char and minimise the release of toxic emissions from the char, and thus, could make PT-char suitable for use as a fuel source. In this study, PT-char was blended with torrefied wood and microalgae biomass to demonstrate the suitability of using PT-char-biomass-fuel blend as an energy feedstock. To this effect, a mixture design of experiments was used to formulate the PT-char biomass blends and regression analysis was employed to select an optimum blend formulation for the combustion and mechanical properties of the blends. Proximate analysis results showed a non-linear increase in the volatile matter and a non-linear decrease in the fixed carbon and ash yield as the biomass ratio increased. The calorific value also increased on an additive basis with increasing biomass proportion. The elemental analysis results showed a decrease in the calcium, zinc and bromine contents and an increase in the potassium and iron contents increased with increasing biomass proportion. Likewise, the sulphur content decreased while the oxygen, hydrogen and nitrogen contents increased with increasing biomass ratio. vi Thus, the fuel properties of the blends improved with increasing biomass ratio and without compromising the calorific value of the PT-char. Moreover, the TG-MS analysis showed that the PT-char and the respective blends did not show any release SO2 up to 650°C. Thus, making the fuel suitable for use in low temperature applications such as household and certain boilers. The results of the regression analysis showed that the blend formulation with the highest proportions of biomass, thus C55-T30-M15, is the optimum blend to produce a solid fuel with a low initial decomposition (214°C) and char ignition temperatures (532°C) as well as maximum burn-out temperature (640°C). In essence, the high thermal reactivity of PT-char is improved when both biomasses are loaded at maximum ratios as per the experimental design. The results of the MS showed a decrease in CO2 and NO2 emissions with increasing biomass proportion. The optimum blend (C55-T30-M15) was found to have a comparably higher gross calorific value (26 MJ/kg), lower sulphur content (1.1 wt.%), low ash yield (11wt.%) and lower concentration of minerals (i.e. zinc) than raw PT-char. In addition, the volatile matter content of the blend (20 wt.%) was found to be higher than that of PT-char and the ignition temperature of the optimum fuel blend was relatively lower and its burnout temperature higher than that of PT char. The MS results revealed that the CO2 and NO2 emissions were higher in the optimum blend than the PT-char. The mechanical properties of the pellets; impact resistance and compressive strength increased with increasing biomass blending ratio and even more so with increasing microalgae ratio. The C55-T30-M15 and C75-T10-M15 were selected as optimum blends using regression analysis and both blends exceeded the benchmark for mechanical properties except for water resistance. The blending did not improve the water resistance and all the blends did not meet the minimum threshold for water resistance. Overall, the blending of PT-char with torrefied wood and microalgae biomass has shown to improve the fuel properties PT-char, and therefore, making it a suitable potential fuel source. , Thesis (MSc) -- Faculty of Science, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Dube, Cleopatra Thulani
- Date: 2021-12
- Subjects: Pyrolysis , Solid fuel reactors
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/58439 , vital:59241
- Description: he thermal decomposition of waste tyres via pyrolysis is considered to be amongst the most promising methods of recycling tyres due to its minimal environmental impact (in terms of reduction in pollution). During pyrolysis, tyres are thermally degraded in an inert environment to produce gas, oil and char. The gas and oil have promising commercialization prospects while the char remains a pollutant despite the strides made in a lot of research to upgrade the char to carbon black, activated carbon and even for reuse as a filler in tyre manufacture. For pyrolysis to be profitable, or worthy of investments, all three of its products (oil, char and gas) need to be valorised. Pyrolysis-derived tyre chars (PT-char) have an energy value equivalent to high rank coals, however, the use of PT char as a solid fuel is uncommon due to the high contents of sulphur and mineral matter as well as low volatile matter content of the PT-char. As such, the combustion of PT-char is characterised by high ignition temperature, low thermal reactivity, and no flame formation due to the low amounts of volatile matter. On the other hand, biomass are clean, renewable feedstock, having low sulphur and mineral matter contents, as well as high thermal reactivity. The blending of PT-char with biomass could potentially improve the combustion properties of PT-char and minimise the release of toxic emissions from the char, and thus, could make PT-char suitable for use as a fuel source. In this study, PT-char was blended with torrefied wood and microalgae biomass to demonstrate the suitability of using PT-char-biomass-fuel blend as an energy feedstock. To this effect, a mixture design of experiments was used to formulate the PT-char biomass blends and regression analysis was employed to select an optimum blend formulation for the combustion and mechanical properties of the blends. Proximate analysis results showed a non-linear increase in the volatile matter and a non-linear decrease in the fixed carbon and ash yield as the biomass ratio increased. The calorific value also increased on an additive basis with increasing biomass proportion. The elemental analysis results showed a decrease in the calcium, zinc and bromine contents and an increase in the potassium and iron contents increased with increasing biomass proportion. Likewise, the sulphur content decreased while the oxygen, hydrogen and nitrogen contents increased with increasing biomass ratio. vi Thus, the fuel properties of the blends improved with increasing biomass ratio and without compromising the calorific value of the PT-char. Moreover, the TG-MS analysis showed that the PT-char and the respective blends did not show any release SO2 up to 650°C. Thus, making the fuel suitable for use in low temperature applications such as household and certain boilers. The results of the regression analysis showed that the blend formulation with the highest proportions of biomass, thus C55-T30-M15, is the optimum blend to produce a solid fuel with a low initial decomposition (214°C) and char ignition temperatures (532°C) as well as maximum burn-out temperature (640°C). In essence, the high thermal reactivity of PT-char is improved when both biomasses are loaded at maximum ratios as per the experimental design. The results of the MS showed a decrease in CO2 and NO2 emissions with increasing biomass proportion. The optimum blend (C55-T30-M15) was found to have a comparably higher gross calorific value (26 MJ/kg), lower sulphur content (1.1 wt.%), low ash yield (11wt.%) and lower concentration of minerals (i.e. zinc) than raw PT-char. In addition, the volatile matter content of the blend (20 wt.%) was found to be higher than that of PT-char and the ignition temperature of the optimum fuel blend was relatively lower and its burnout temperature higher than that of PT char. The MS results revealed that the CO2 and NO2 emissions were higher in the optimum blend than the PT-char. The mechanical properties of the pellets; impact resistance and compressive strength increased with increasing biomass blending ratio and even more so with increasing microalgae ratio. The C55-T30-M15 and C75-T10-M15 were selected as optimum blends using regression analysis and both blends exceeded the benchmark for mechanical properties except for water resistance. The blending did not improve the water resistance and all the blends did not meet the minimum threshold for water resistance. Overall, the blending of PT-char with torrefied wood and microalgae biomass has shown to improve the fuel properties PT-char, and therefore, making it a suitable potential fuel source. , Thesis (MSc) -- Faculty of Science, 2021
- Full Text:
- Date Issued: 2021-12
Effect of coal and microalgae biomass co-firing on CO2, SO2 and NOx emissions: An experimental evaluation
- Authors: Magida, Nokuthula Ethel
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53817 , vital:45984
- Description: There is increasingly stringent legislation on the environmental impact of energy production from coal combustion, and this has led to growing pressure to reduce the emission of greenhouse gases (GHGs). Thus, there is a significant need to develop and implement clean coal combustion technologies that would reduce the environmental gas pollutants. For power generation, the co-firing of biomass fuels at conventional coal-fired power stations is recognised as one of the low-cost, low-risk options to achieve significant reductions in GHG emissions. When coal is co-utilized with biomass there is added attractiveness because the biomass is CO2 neutral, and there is interest in using waste biomass and microalgae. Thus, the co-combustion of coal and biomass for energy production results in pollutant reduction, especially in the emissions of NOx, SOx, volatile organic compounds and polyaromatic hydrocarbons. The synergistic activity observed for toxic organic emissions is not well understood and is thought to involve chemical interaction between the volatiles from each fuel coupled with possible catalytic activity from the inorganic constituents of the fuels. The characterization of co-firing products and gases emitted from coal and microalgae (particularly the Scenedesmus strain) co-combustion has received limited attention. Therefore, this study seeks to understand possible interactions occurring during co-combustion of coal and Scenedesmus microalgae (Coalgae®). Additionally, the study aims to determine the effect of co-firing coal and Scenedesmus microalgae on CO2, SO2 and NOx emissions. The term “Coalgae®” refers to the mixture of coal and microalgae biomass. The study looks at physico-thermal characteristics as well as CO2, SO2 and NOx emissions of various coal-microalgae blending ratios by mass; 100:0 (coal), 95:5 (Coalgae® 5%), 90:10 (Coalgae® 10%), 85:15 (Coalgae® 15%) and 80:20 (Coalgae® 20%). Characterization techniques carried out included proximate and ultimate analyses, Fourier-transform infrared (FT-IR) and Scanning electron microscopy and X-ray energy dispersive spectroscopy (SEM/EDS). For combustion studies two techniques were applied. Low heating rate was obtained through a Thermogravimetric-Mass spectrometer analysis (TG-MS). Other combustion experiments were performed on the five lumpy fuels (coal and Coalgae® 5% - 20%) exposed to the flame in a fixed-bed combustion reactor. The emission concentrations of CO2 (%), NOx (ppm) and SO2 (ppm) of coal and Coalgae® blends were measured during the combustion of the five materials using a Lancom 4 portable flue gas analyser. The mass reduction (g) and temperature (°C) at the reactor exit were recorded during the combustion tests to compare the combustion behaviour of the four mixtures to that of raw coal. TG-DTG curves of coal and microalgae confirmed that the combustion behaviour of these materials was different. Coal showed one reaction during the combustion process, while microalgae and the Coalgae® blends showed three reactions. A significant reduction in activation energies of 160.4 kJ/mol, 159.6 kJ/mol, 151.3 kJ/mol, and 134.2 kJ/mol for Coalgae® 5% - Coalgae® 20%, respectively, compared to coal (161.3 kJ/mol) was achieved. The lowering of activation energy could be attributed to the relative fixed carbon content. SEM morphology images of ash obtained from the combustion of coal and Coalgae® 5% - 20% confirmed changes in devolatilization and combustion behaviour of solid raw fuel. The ash of Coalgae® blends had higher fluxing elements (Fe, Ca, K and Mg) than coal and this shows possibility of slagging and fouling in combustion systems. The Coalgae® blends showed a synergistic effect due to different combustion characteristics of coal and Scenedesmus microalgae. The combustion results obtained from the fixed-bed reactor showed significant reductions in concentrations of CO2, SO2 and NOx emissions for Coalgae® blends compared to baseline coal. Microalgae reduced CO2 emissions from baseline coal by 14.9%, 19.5%, 23.5% and 31.4% for Coalgae® 5%, 10%, 15% and 20%, respectively. SO2 reductions of 1.9%, 10.6%, 15.8% and 18.2%, and NOx reductions of 22.4%, 26.1%, 24.4% and 16.9% were achieved with Coalgae® 5%, 10%, 15% and 20%, respectively. Moreover, the combustion efficiency of Coalgae® blends increased significantly by up to 14.5% from baseline coal (86.4%) to Coalgae® 20% (98.9%). Based on the above findings, the co-firing of coal and Scenedesmus microalgae biomass was necessary for the reduction of CO2, SO2, and NOx emissions. As such, Coalgae® blends can be considered as alternative fuels in any coal driven process for energy generation. , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-12
- Authors: Magida, Nokuthula Ethel
- Date: 2021-12
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53817 , vital:45984
- Description: There is increasingly stringent legislation on the environmental impact of energy production from coal combustion, and this has led to growing pressure to reduce the emission of greenhouse gases (GHGs). Thus, there is a significant need to develop and implement clean coal combustion technologies that would reduce the environmental gas pollutants. For power generation, the co-firing of biomass fuels at conventional coal-fired power stations is recognised as one of the low-cost, low-risk options to achieve significant reductions in GHG emissions. When coal is co-utilized with biomass there is added attractiveness because the biomass is CO2 neutral, and there is interest in using waste biomass and microalgae. Thus, the co-combustion of coal and biomass for energy production results in pollutant reduction, especially in the emissions of NOx, SOx, volatile organic compounds and polyaromatic hydrocarbons. The synergistic activity observed for toxic organic emissions is not well understood and is thought to involve chemical interaction between the volatiles from each fuel coupled with possible catalytic activity from the inorganic constituents of the fuels. The characterization of co-firing products and gases emitted from coal and microalgae (particularly the Scenedesmus strain) co-combustion has received limited attention. Therefore, this study seeks to understand possible interactions occurring during co-combustion of coal and Scenedesmus microalgae (Coalgae®). Additionally, the study aims to determine the effect of co-firing coal and Scenedesmus microalgae on CO2, SO2 and NOx emissions. The term “Coalgae®” refers to the mixture of coal and microalgae biomass. The study looks at physico-thermal characteristics as well as CO2, SO2 and NOx emissions of various coal-microalgae blending ratios by mass; 100:0 (coal), 95:5 (Coalgae® 5%), 90:10 (Coalgae® 10%), 85:15 (Coalgae® 15%) and 80:20 (Coalgae® 20%). Characterization techniques carried out included proximate and ultimate analyses, Fourier-transform infrared (FT-IR) and Scanning electron microscopy and X-ray energy dispersive spectroscopy (SEM/EDS). For combustion studies two techniques were applied. Low heating rate was obtained through a Thermogravimetric-Mass spectrometer analysis (TG-MS). Other combustion experiments were performed on the five lumpy fuels (coal and Coalgae® 5% - 20%) exposed to the flame in a fixed-bed combustion reactor. The emission concentrations of CO2 (%), NOx (ppm) and SO2 (ppm) of coal and Coalgae® blends were measured during the combustion of the five materials using a Lancom 4 portable flue gas analyser. The mass reduction (g) and temperature (°C) at the reactor exit were recorded during the combustion tests to compare the combustion behaviour of the four mixtures to that of raw coal. TG-DTG curves of coal and microalgae confirmed that the combustion behaviour of these materials was different. Coal showed one reaction during the combustion process, while microalgae and the Coalgae® blends showed three reactions. A significant reduction in activation energies of 160.4 kJ/mol, 159.6 kJ/mol, 151.3 kJ/mol, and 134.2 kJ/mol for Coalgae® 5% - Coalgae® 20%, respectively, compared to coal (161.3 kJ/mol) was achieved. The lowering of activation energy could be attributed to the relative fixed carbon content. SEM morphology images of ash obtained from the combustion of coal and Coalgae® 5% - 20% confirmed changes in devolatilization and combustion behaviour of solid raw fuel. The ash of Coalgae® blends had higher fluxing elements (Fe, Ca, K and Mg) than coal and this shows possibility of slagging and fouling in combustion systems. The Coalgae® blends showed a synergistic effect due to different combustion characteristics of coal and Scenedesmus microalgae. The combustion results obtained from the fixed-bed reactor showed significant reductions in concentrations of CO2, SO2 and NOx emissions for Coalgae® blends compared to baseline coal. Microalgae reduced CO2 emissions from baseline coal by 14.9%, 19.5%, 23.5% and 31.4% for Coalgae® 5%, 10%, 15% and 20%, respectively. SO2 reductions of 1.9%, 10.6%, 15.8% and 18.2%, and NOx reductions of 22.4%, 26.1%, 24.4% and 16.9% were achieved with Coalgae® 5%, 10%, 15% and 20%, respectively. Moreover, the combustion efficiency of Coalgae® blends increased significantly by up to 14.5% from baseline coal (86.4%) to Coalgae® 20% (98.9%). Based on the above findings, the co-firing of coal and Scenedesmus microalgae biomass was necessary for the reduction of CO2, SO2, and NOx emissions. As such, Coalgae® blends can be considered as alternative fuels in any coal driven process for energy generation. , Thesis (MSc) -- Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-12
Bioethical analysis of COVID19, WASH/waste and related disaster management implications
- Authors: Iheanetu, Chidinma Uchenna
- Date: 2022-04-06
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/232250 , vital:49975
- Description: Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2022
- Full Text:
- Date Issued: 2022-04-06
- Authors: Iheanetu, Chidinma Uchenna
- Date: 2022-04-06
- Subjects: Uncatalogued
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/232250 , vital:49975
- Description: Thesis (MSc) -- Faculty of Science, Biotechnology Innovation Centre, 2022
- Full Text:
- Date Issued: 2022-04-06