Synthesis and characterization of MXS (M = Mo & V) and carbon supported MXS nanocomposites as Pt-free counter electrodes for electrode for DSSC application
- Authors: Bede, Asanda
- Date: 2020
- Subjects: Voltammetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/18599 , vital:42612
- Description: It has been reported that the morphology, crystalline phase composition and electrochemical properties of counter electrode materials such MxS (Mo, V) and carbon supported MxS (Mo, V) composite nanomaterials was of considerable importance because it governs the efficiency of many photon assisted chemical and physical reactions in dye sensitized solar cells (DSSCs). The efficiency of DSSCs with composite counter electrode materials is reliant on the stability of the photochemistry reactions which can be optimized by appropriate doping levels of the composite materials. Moreover, the microstructure such as surface area, distribution of the MxS (Mo, V) and carbon supported MxS (Mo, V) composite nanomaterials, and the stability of the electrostatic bonds between the MxS (Mo, V) with the carbon support also play a significant role in the performance of the DSSCs. This work evaluates the effect of different mole ratios of the MxS (Mo, V) and carbon supported MxS (Mo, V) composite nanomaterials on the morphological, structural and electrochemical properties of the composite materials. MoS2 nanoflakes nanostructures have been synthesized by hydrothermal technique using sodium orthovanadate (Na2MoO4) as precursor. In this work Carbon supported MoS2 NFs have been prepared by physically/chemically mixing different mole ratios of MoS2 NFs with multi-walled carbon nanotubes (MWCNTs) and polyvinylidene in N-methyl-2-pyrrolidinone. The morphological, structural and electrochemical properties of the composite counter electrode materials have been investigated using SEM, XRD FTIR, TEM, RS and CV. SEM analysis has revealed the presence of large MoS2 nanoflakes (NFs) as synthesized. SEM analysis has also revealed significant change in the surface morphology of carbon supported MoS2 composite nanostructures with the change in the mole ratio of the MoS2 NFs and carbon support multi-walled carbon nanotubes. Structural analysis through HRTEM analysis revealed a d-spacing of 0.65 nm with a corresponding (002) lattice plane belonging to a trigonal crystalline phase of MoS2. Also, HRTEM analysis has revealed d-spacing of 0.291 nm corresponding to 002 plane of MWCNTs. Raman spectroscopy has revealed Characteristic Raman vibration frequencies and symmetries at 264.6 cm-1(Eg), 354.2 cm-1 (Ag ) belonging trigonal phase of MoS2 (1T-MoS2). FTIR analysis has revealed a narrow peak at 457.6 cm-1 due Mo-S vibration bond. This observation confirms the success of synthesis of MoS2 nanostructures. Cyclic voltammetry (CV), charge-discharge (CD) and electrochemical impedance spectroscopy (EIS) measurements have revealed that the ratio 6:3:1 have shown to be optimum ratio due to its large reduction rate compared to pristine MoS2 NFs and other carbon supported MoS2 NFs. Calculated Rreduction for the carbon supported MoS2 NFs is the order 3:6:1>1:8:1>6:3:1>8:1:1 indicating the trend of ratio 3:6:1 appeared to have higher reduction rate than the rest of the material and it had far less ΔEpp than the rest of other ratios. All CV curves for both pristine MoS2 NFs and carbon supported MoS2 NFs confirmed a distinct Faradic characteristic. The VS2 nanosheets (NSs) and carbon supported VS2 NSs were also effectively synthesized via hydrothermal method. The SEM micrographs for VS2 NSs and carbon supported VS2 NSs samples reveals level increased. Furthermore, SEM-EDX analysis have confirmed the presence of V and S as well as C and O on carbon supported VS2 nanocomposites, and it clearly shown a gradually blending as the ratios increases. The structural studies through XRD analysis have revealed peaks at 2θ angles of 15.4◦, 28.2◦, 34.2◦, 36.2◦, 43.3◦,48.3◦, 54.4◦, 57.7◦ and 66.2◦ which correspond to the lattice planes (001), (002), (100), (011), (102), (003), (110), (103) and (201) belonging to hexagonal VS2 (H-VS2) crystalline phase as per JCPDS card 36-1139. The HRTEM have revealed that the VS2 NSs have an edge to edge length of ~ 0.294 – 1.248 µm. Also, HRTEM micrographs of VS2 NSs have revealed interplanar d spacing of 0.571 nm belonging to the (001) lattice plane of hexagonal VS2 (H-VS2) structure. FTIR analysis have shown a peak at 558 cm-1 attributed to V-S which is evident that sulfur has bonded with the metal (V) and is in agreement with EDS. CV, CD and EIS measurements have shown that the ratio 1:8:1 is more superior to VS2 NSs and other carbon supported VS2 NSs. Based on Rreduction for the carbon supported nanosheets VS2 nanosheets are ordered as 1:8:1>3:6:1>6:3:1>8:1:1. Carbon supported VS2 NSs of the mole ratio 1:8:1 showed a small resistance of 0.32 Ω. This is further evidence that the carbon supported VS2 NSs of the mole ratio 1:8:1 in addition to revealing excellent catalytic behaviour is also more chemically stable and has good conductivity properties._________
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- Date Issued: 2020
Synthesis of 2,4-Xylidine in continuous flow systems
- Authors: Sagandira, Mellisa Brenda
- Date: 2020
- Subjects: Chemistry, Physical and theoretical -- Research , Chemistry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/49270 , vital:41616
- Description: The continuous flow synthesis of 2,4-xylidine, an important compound in the fine chemical, pharmaceutical as well as the dyes and pigments industries was investigated in this study utilizing 1,3-dimethylbenzene as starting material. The first step involves the highly exothermic nitration of 1,3-dimethylbenzene with mixed acid to afford two nitro isomers, namely 1,3-dimethyl-2-nitrobenzene and 2,4-dimethyl-1-nitrobenzene. Since 2,4-xylidine is the targeted isomer, it is important to get a higher proportion of its nitration precursor 2,4-dimethyl-1-nitrobenzene. A safe and efficient synthesis of 2,4-dimethyl-1-nitrobenzene was therefore developed in continuous flow. This was aided by the micro reactor’s large surface area-to-volume ratio, one of the many features of continuous flow synthesis that enable rapid dissipation of heat allowing exothermic reactions to be conducted safely at ambient or higher temperatures. Two nitration protocols were developed using different micro reactors, a sonicated 1 ml PTFE tube reactor and 2 ml Uniqsis chip reactor. Using a sonicated PTFE tube reactor at room temperature and 15 min residence time, 2,4-dimethyl-1-nitrobenzene was afforded in 100 % conversion and 80 % selectivity. An increase in selectivity to 95 % and 90 % conversion towards 2,4-dimethyl-1-nitrobenzene was achieved using a 2 ml Uniqsis chip reactor at room temperature in 6 min residence time. This was accounted for due to efficient mixing of the two phases brought about by the reactor’s mixing structures, which are designed to create turbulent mixing. Scale-up synthesis of 2,4-dimethyl-1-nitrobenzene was conducted in a 4.5 ml LTF-XXL-ST-04 reactor at room temperature and 6 min residence time affording 90 % conversion and 95 % selectivity with a throughput of 16.6 g/h. Subsequently, reduction of 2,4-dimethyl-1-nitrobenzene to afford 2,4-xylidine was investigated in a 1 ml PTFE tube reactor (0.8 mm ID) using hydrazine in the presence of iron (III) 2,4-pentanedionate catalyst. Maximum conversion of 75 % was achieved at 170 °C in 15 min residence time. A more efficient reduction protocol was developed in a 2.7 ml packed column reactor (10 mm ID) using hydrazine in the presence of Pd/C at 50 °C and 2.5 min residence time affording 94 % conversion towards 2,4-xylidine. Lastly, multistep synthesis of 2,4-xylidine was performed using optimum conditions found using the 2 ml Uniqsis chip reactor and 2.7 ml packed column reactor with the incorporation of a phase separator. Joining the two reactors into a single continuous step afforded 100 % conversion and 95 % selectivity towards 2,4-xylidine with 8 min total residence time. Nitration of other organic compounds followed by reduction of the resultant nitro products was also investigated under respective optimum conditions determined for nitration of 1,3-dimethylbenzene and reduction of 2,4-dimethyl-1-nitrobenzene.
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- Date Issued: 2020
Synthesis, crystal structures and characterization of metal–organic framework architectures involving dinuclear copper(ii) benzoic acid derivative complexes
- Authors: Ndima, Lubabalo
- Date: 2020
- Subjects: Supramolecular chemistry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/46783 , vital:39657
- Description: Structural copper(II) complexes with aromatic carboxylic acids show a wide spectrum of coordination schemes. Studies of dicopper(II) carboxylates have been associated with a variety of interests for their catalytic, biological and magnetic applications [1]. Various novel dinuclear copper(II) complexes [Cu2(X-benzoate)4L2] with varying substituents (X = CH3, F, Cl, Br, I, NO2 & OCH3) with a desired octahedral geometry have been synthesized. The various complexes were characterized by single crystal X-ray diffraction studies, spectroscopic and thermal methods (UV/Vis, FTIR and TGA, DSC). In most cases, the structures consists of centrosymmetric dimers in which the Cu atoms show a square pyramidal CuO5 coordination. In all cases, dimeric paddle wheel complexes where two copper(II) ions are held together by four benzoates (forming syn– syn bridges between the copper atoms) and the apical coordination site occupied by a solvent ligand (L) or supramolecular linker were obtained. The dimers are extended into 1D chains that result from hydrogen bonding between the coordinated methanol (solvent ligand) on one Cu(II) and the carboxylate group on an adjacent Cu(II) dimer, including interactions arising from various substituents. π–π Stacking interactions are found to be present in the various crystal structures forming 3D supramolecular array. FTIR and UV/Vis spectra of each complex have shown how the resonance and inductive effect of each substituent affects spectral data of each complex.
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- Date Issued: 2020
Synthesis, photophysicochemical properties and photodynamic therapy activities of indium and zinc phthalocyanines when incorporated into Pluronic polymer micelles
- Authors: Motloung, Banele Mike
- Date: 2020
- Subjects: Indium , Zinc , Phthalocyanines , Polymers , Photochemotherapy , Micelles
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/167529 , vital:41489
- Description: This thesis reports on the syntheses, photophysicochemical properties and photodynamic therapy activities of symmetrical metallophthalocyanines (MPcs) when alone or when incorporated into Pluronic polymer micelles. The Pcs contain either zinc or indium as central metals and have phenyldiazenylphenoxy, pyridine-2-yloxy and benzo[d]thiazol-2-ylthio as ring substituents. Spectroscopic and microscopic techniques were used to confirm the formation MPcs with micelles. The photophysics and photochemistry of the Pcs were assessed when alone and with micelles. All the studied Pcs showed good photophysicochemical behavior with relatively high triplet and singlet oxygen quantum yields corresponding to their low fluorescence quantum yields. The Pcs with indium in their central cavity exhibited higher triplet and singlet oxygen quantum yields in comparison to their zinc counterparts due to the heavy atom effect obtained from the former. The in vitro dark cytotoxicity and photodynamic therapy of the Pc complexes and conjugates against MCF7 cells was tested. All studied Pc complexes alone and with micelles showed minimum dark toxicity making them applicable for PDT. All complexes displayed good phototoxicity < 50% cell viability (except for complex 2 > 50% cell viability) at concentrations ≤100 μg/mL, however the conjugates showed < 45% cell viability at concentrations ≤ 100 μg/mL, probably due to the small micellar size and EPR effect. The findings from this work show the importance of incorporating photosensitizers such as phthalocyanines into Pluronic polymers micelles and making them water soluble and ultimately improving their photodynamic effect.
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- Date Issued: 2020
System analysis of fatigue in pilots and co-pilots executing short-hall flight operations
- Authors: Bennett, Cleo Taylor
- Date: 2020
- Subjects: Air pilots -- Health and hygiene , Fatigue , Work environment -- Psychological aspects , Work environment -- Physiological aspects
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/146622 , vital:38543
- Description: Background: This study was conducted as part of Denel’s South African Regional Aircraft (SARA) development project. Regional aircraft have a maximum flight time of 60 minutes. Hence, the study focuses on matters pertaining to the short-haul flight context. Pilot fatigue has been recognised as a safety concern in the aviation industry. It impacts on pilot performance across the board, not least in the short-haul context. However, the specific factors that lead to pilot fatigue in short-haul operations have not been well researched. Research Aim: To identify and examine the factors which influence pilot/co-pilot fatigue in short-haul aviation contexts. Method: Fatigue is multifaceted, and has multiple definitions and descriptions. It is acknowledged as a complex phenomenon, the development of which is dynamically influenced by various factors. Thus, a systems approach based on the work system model by Smith and Carayon-Sainfort (1989) was adopted for this study. A systems analysis was conducted in two parts: 1) a literature analysis, and 2) expert interviews. Results: Both the literature analysis and the interviews indicated that pilot fatigue in short-haul flight operations represent composite system outcomes influenced by various factors. The factors identified were structured (systematised) into categories, namely organizational factors, task-related factors, environmental factors, factors linked to technology and tools, and non-work-related factors specific to the individual pilot. An example of a task-related factor would be the performance by pilots of multiple take-offs and landings; organizational factors include work time arrangements and duty scheduling (e.g. unpredictable schedule, early starts/late finishes, number of flight sectors in a shift, extended working hours, numerous consecutive work days, standby duties, flight, duty and rest limitations (regulations and guidelines); and short turnaround periods); environmental factors might include the small pressurised cockpit environment, movement restriction, very low humidity, low air pressure, vibrations, high noise levels, low light intensity light, and inclement weather); there are many examples of how tools and technology utilized by pilots might affect their fatigue levels; and finally, pilot-specific non-work-related factors would include things like the pilot’s age, health (lifestyle), family stress, work experience and sleep environment. All of these factors were identified during the literature analysis and have a significant bearing on how fatigue could present in short-haul pilots/co-pilots. Other important fatigue-related factors revealed during the expert interviews included, organizational culture, time management, health implications of fatigue, and management of fatigue. Conclusions: Pilot fatigue is a complex and multi-factorial physiological condition. There are many interacting components which contribute to pilot fatigue in short-haul operations. These should be viewed from an integrated perspective and holistic, systems-based approaches should be taken to manage these issues, particularly in the context of short-haul operations. This would optimize pilot performance and well-being and, most importantly, improve the safety of the work environment to enhance overall operation safety. Limitations: The study does not quantify the contributions made to pilot fatigue by the various factors explored. Therefore, care needs to be taken when designing and implementing interventions based on this research.
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- Date Issued: 2020
Tax revolts: an international perspective
- Authors: Tinotenda, Tariro Chizanga
- Date: 2020
- Subjects: Taxation -- Public opinion , Taxation -- Law and legislation -- South Africa , Income tax -- South Africa , South Africa -- Economic conditions , Fiscal policy -- South Africa
- Language: English
- Type: text , Thesis , Masters , MComm
- Identifier: http://hdl.handle.net/10962/166116 , vital:41330
- Description: The main goal of this study is to investigate whether tax revolts currently taking place and apparently threatening to take place in South Africa follow patterns shown in past international tax revolts or follow a unique pattern of their own. Tax revolts or tax rebellions are not a new phenomenon; they can be traced back to the beginning of time. Renowned tax revolts of the past include the Magna Carta and the Peasants’ Revolt in England, the Boston Tea Party, the Whiskey Rebellion, the Zimbabwean poll tax revolt, the Bambatha rebellion, the Tigre Rebellion, Proposition 13 and Margaret Thatcher’s poll tax revolt. These tax revolts were usually caused by the high burden of taxation, excessive government expenditure, corruption of government officials, declining tax morale of taxpayers and taxpayers’ perceptions of unfairness. In South Africa, elements of tax revolts have been on the rise. There has been a tax revolt against the e-tolling system in Gauteng since 2013. Non-payment of municipal rates is another form of tax revolt that has been and is happening in South Africa. Trade unions have also threatened strikes and mass action against various tax changes, including the value-added tax increase. Taxpayers, through media reporting, have been witnessing an increase in the use of taxpayers’ money for non-governmental agendas or overstated budgets. An increasing number of South Africans have been emigrating financially from South Africa to avoid a high taxation burden. The study falls within a post-positivist paradigm and an interpretive methodology is applied in the present research. The methodology is based on the fact that the social reality of tax revolts is not singular or objective, instead it is influenced by human experiences and social contexts. The study finds that tax revolts are currently occurring and threatening to occur in South Africa. The patterns of South African tax revolts are to a great extent similar to the patterns of international tax revolts, indicating the universalism of tax revolts. The study also confirms that South African tax revolts are, to a certain extent, unique.
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- Date Issued: 2020
Technology in conservation: towards a system for in-field drone detection of invasive vegetation
- Authors: James, Katherine Margaret Frances
- Date: 2020
- Subjects: Drone aircraft in remote sensing , Neural networks (Computer science) , Drone aircraft in remote sensing -- Case studies , Machine learning , Computer vision , Environmental monitoring -- Remote sensing , Invasive plants -- Monitoring
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/143408 , vital:38244
- Description: Remote sensing can assist in monitoring the spread of invasive vegetation. The adoption of camera-carrying unmanned aerial vehicles, commonly referred to as drones, as remote sensing tools has yielded images of higher spatial resolution than traditional techniques. Drones also have the potential to interact with the environment through the delivery of bio-control or herbicide, as seen with their adoption in precision agriculture. Unlike in agricultural applications, however, invasive plants do not have a predictable position relative to each other within the environment. To facilitate the adoption of drones as an environmental monitoring and management tool, drones need to be able to intelligently distinguish between invasive and non-invasive vegetation on the fly. In this thesis, we present the augmentation of a commercially available drone with a deep machine learning model to investigate the viability of differentiating between an invasive shrub and other vegetation. As a case study, this was applied to the shrub genus Hakea, originating in Australia and invasive in several countries including South Africa. However, for this research, the methodology is important, rather than the chosen target plant. A dataset was collected using the available drone and manually annotated to facilitate the supervised training of the model. Two approaches were explored, namely, classification and semantic segmentation. For each of these, several models were trained and evaluated to find the optimal one. The chosen model was then interfaced with the drone via an Android application on a mobile device and its performance was preliminarily evaluated in the field. Based on these findings, refinements were made and thereafter a thorough field evaluation was performed to determine the best conditions for model operation. Results from the classification task show that deep learning models are capable of distinguishing between target and other shrubs in ideal candidate windows. However, classification in this manner is restricted by the proposal of such candidate windows. End-to-end image segmentation using deep learning overcomes this problem, classifying the image in a pixel-wise manner. Furthermore, the use of appropriate loss functions was found to improve model performance. Field tests show that illumination and shadow pose challenges to the model, but that good recall can be achieved when the conditions are ideal. False positive detection remains an issue that could be improved. This approach shows the potential for drones as an environmental monitoring and management tool when coupled with deep machine learning techniques and outlines potential problems that may be encountered.
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- Date Issued: 2020
Technology readiness of public school teachers : a study in Nelson Mandela Bay Municipality
- Authors: Ebongue, Placide Mbella
- Date: 2020
- Subjects: Teachers -- Training of -- South Africa -- Nelson Mandela Bay Municipality Educational technology -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Masters , MDS
- Identifier: http://hdl.handle.net/10948/49659 , vital:41766
- Description: Globally, it is well documented that technology integration (Information & Communication Technology) in teaching & learning environments improve educational experiences and outcomes. The information revolution also conditions the global collective to prioritise and invest in education. In South Africa, basic education is increasingly aiming to integrate technology in its teaching and learning processes, as is already common practice in the higher learning environment. Policies and supporting educational legislation must, therefore, be geared to steer teacher training emphasis in this regard, especially for primary schools. To anchor economic developments, important parameters to consider, include the readiness of teachers to use technology in the classroom, measured through the technology readiness index (TRI) and a variety of demographic indices. These reveal trends among teachers and their interaction with learners while delivering subject content in the classroom. In the Nelson Mandela Bay Municipality (NMBM) (Port Elizabeth and Uitenhage) area, Eastern Cape, South Africa, 32 schools totalling 70 teachers were evaluated using an online survey, based on a TRI model, initially developed by Parasuraman and later refined by Parasuraman and Colby. Results showed that teachers in the NMBM area have a medium to high technology propensity, with a readiness index score of 3.445 out of five. The demographic analysis also revealed that teachers are optimistic about technology and motivated about making it work in their classroom. These positive indicators towards technology (ICT) adoption encourage economic investments in basic education; however, further study is recommended to investigate implementation (and comparison to other provinces), therefore, informing the specific magnitude and type of investments needed in the Eastern Cape. An implementation model, which promotes ICT policy with a combination of software, hardware and internet access, appropriately incorporated in teaching and learning objectives, is encouraged to promote economic developments.
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- Date Issued: 2020
The African Continental Free Trade Agreement in Context
- Authors: Conjwa, Siviwe
- Date: 2020
- Subjects: Customs unions -- Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10948/47347 , vital:39849
- Description: The economic integration of the African continent has been an ideal pursued by most African states for a considerable number of years. This has been due to the notion that regional integration offers greater opportunities for developing states participating in global trade. Regional integration is regarded by some states as crucial to the alleviation of poverty on the African continent and, to this end, several African states have formed part of several regional blocs on the continent. The African Continental Free Trade Agreement (hereafter the AfCFTA) was signed in 2018, with the intention of removing barriers to the free movement of goods and services on the continent. The rationale behind the AfCFTA is that greater opportunities for the development of the African continent can be unlocked if the economies of the continent can be amalgamated into a single market. The AfCFTA is set to be the world’s largest free trade area, bringing together 55 states with a combined population of more than 1 billion people. This research contextualises the establishment of the AfCFTA within the greater context of the integration agenda of the African continent. Of particular significance is the role of the already existing Regional Economic Communities in the formulation of the AfCFTA, as well as the question as to whether global trade provisions regulating the creation of free trade areas have been complied with by the AfCFTA. The manner in which regional agreements are implemented by member states is also an important discussion that forms a part of this research. This is to ensure that some of the potential challenges in the implementation of the AfCFTA are laid bare, so as to ensure that the objectives thereof are attained as envisaged.
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- Date Issued: 2020
The application value and most appropriate mapping scales for site classification and evaluation in the South African forest industry
- Authors: Sibhakabhaka, Thembisa
- Date: 2020
- Subjects: Forests and forestry -- South Africa , Forest products industry -- South Africa Geographic information systems
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/49281 , vital:41617
- Description: The South African forest industry is challenged with aspects related to socio-political developments, conflicts with biodiversity values, uncertainties related to climate change, several biotic and abiotic risks, and a limited potential for expansion. For this reason, efficient and optimal land-use is essential, which requires sustainable forest management practices and accurate information and decision support systems. Tree growth patterns, productivity and risks vary according to changes in geology, topography, climate and soil conditions. It is therefore required that forest managers, planners and researchers have a conceptual understanding of the concept of forest site classification and evaluation. This is essential not only for improved levels resilience, but also to maintain a competitive industry in terms of socio-economic and environmental performance. The first chapter of the study aimed to investigate the perceptions and interpretations of a range of representative stakeholders from the forestry industry regarding the value, shortcomings, requirements and design of forest site classification and evaluation systems in use in the local industry. A questionnaire with 16 questions was used for this purpose, and data was analysed using quantitative and qualitative techniques. Results indicated variable levels of understanding amongst respondents of terminology and the nature of systems used in industry. Trends in responses were influenced by the background of stakeholders, the role of individuals in the value chain of forestry as well as past experiences. The perceived importance and value of potential site evaluation applications varied substantially amongst different stakeholders. Results point towards a narrow-focus application for site classification and evaluation systems for site-specific forestry, with a lesser regard with aspects of risk management and environmental performance. Several technical aspects related to site variables, data resolution and scale of presentation were also questioned by participants. Listed priorities for research and development include the integration of site classification and evaluation systems into corporate information systems, modernizing technology, more appropriate site evaluation models, advanced climatic modelling and the development of indices of water and nutrient availability related to forest productivity. There is general agreement for the development of a national forest site classification system. The value of this part of the study lies in the contribution it makes towards our knowledge of stakeholder perceptions regarding site classification and evaluation, as well as the valuable comments made by participants for the refinement of such systems that can serve as indicators for entities involved in education, governance and strategic forest management. The second data chapter of the study involved the development of high-resolution site classification systems in the form of Site Types for two selected study areas in South Africa, one located in Mpumalanga, and the other in the southern Cape. This enabled a comparative analysis with existing low-resolution Land Type classifications that were developed by different authors for the same two study areas, in terms of its reliability, accuracy and general usefulness for applications in the plantation forestry value chain. The comparison of the two types of classification systems revealed that the climate data forming part of the database were of equal accuracy and resolution. However, an obvious difference was detected in the information pertaining to soil in terms of descriptive and spatial data. In the case of both study areas, the Site Type classification systems revealed many soil and geological features that were not indicated by the lower-resolution Land Type systems. Variation in characteristics related to parent material, soil classification, soil depth, intensity of subsoil wetness and soil organic matter were not adequately reflected in these systems. This can potentially have important implications for applications such as species choice, predictions of yield, nutrient optimization, ratings of soil resilience, biodiversity management and evaluations for carbon sequestration potential. The data forming part of this study indicate that although Land Type classification systems can provide valuable support at strategic levels of planning and management, there are several limitations for use at finer scales of resolution. The final chapter of the study includes an investigation and qualitative comparison of the usefulness of Site Type vs. Land Type classification systems, based on existing knowledge in the industry. The two systems are compared in terms of its input towards the following applications: site-species matching, timber yield prediction, site amelioration / site preparation requirements, nutrient management requirements, vegetation management / weed control, management of pests and diseases, determination of risk for soil compaction, soil erosion and nutrient loss, decision making regarding forest engineering operations, prediction of wood / fibre properties, biodiversity management and lastly planning of research activities / priorities. This analysis indicated that applications that require data on only climate and general soil patterns can be supported with equal success by both types of site classification systems. On the other hand, in cases where high-resolution data on site factors are required, Land Type classification systems had numerous shortcomings and received a much lower rating of suitability. The outcome of the study can provide guidance on the development and design of future site classification and evaluation systems for the South African forest industry. High-resolution databases of key site factors should receive priority, together with the development of decision support systems based on causal relationships. This will contribute to the resilience and sustainability of an industry that is increasingly confronted with questions related to the placement, design and management of forest plantations.
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- Date Issued: 2020
The benefits and challenges of implementing the Equator Principles: the case of four large banks in South Africa, through the eyes of project finance teams
- Authors: Baloyi, Glenda
- Date: 2020
- Subjects: Financial institutions -- South Africa -- Moral and ethical aspects , Sustainable development -- South Africa , Project management -- South Africa -- Finance
- Language: English
- Type: text , Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/126165 , vital:35855
- Description: The purpose of this research was to investigate the benefits and challenges of implementing the Equator Principles (EPs) by the four large banks in South Africa who are signatories to the framework. This was investigated through the eyes of the project finance teams. The research focused on the perceptions of the project finance team. The EPs are voluntary standards, to date they have been adopted by 94 financial institutions. Financial institutions that have adopted the EPs, benefit by having a competitive advantage of getting involved with high risk projects / developments. The Equator Principles resulted in having environmental and social risk policies and structures to manage these risks. This research was conducted using mixed methods and followed the post-positivist paradigm. The research found that the project finance teams were aware of the environmental, social and governance risks associated with project finance transactions. Furthermore, they understood the need to have the Environmental, Social and Governance (ESG) risk assessment during the credit process. This research found out that the benefits of the EPs outweigh the challenges, as they promote responsible investment, thus promoting the reputation of the investor. The EPs requires the client / borrower to conduct an environmental and social impact assessment and commit to covenants that are binding in the financial legal agreements. By having processes and strategies that promote responsible investment in the financed projects / development, this gives the Equator Principles Financial Institution (EPFI) the advantage of competing in the international market. EPs may indirectly influence the financial institutions that have not adopted the EPs, to promote responsible investment by applying ESG risk assessment processes as required by the banks that have adopted the EPs. EPs lack of capacity such as human resources, policies, funds and structures is the reason why companies do not adopt responsible investment is their operation and not incorporating them in the decision-making process. Some EPFI are not committed the EPs and become free riders. Other EPFI are not complying with the EPs and this causes uncertainties with regards to the legitimacy of the ES standards. EPs are ambiguous, subjective and voluntarism can make it difficult to be achieved by the EPFI. EPs increases the approval process for the financial institution to conclude the transaction, thus delaying the start of a needed project / development. And that EPFI may be forced to have fewer clients as a result of the funding requirements required by EPs.
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- Date Issued: 2020
The catchup games: a novella
- Authors: Nstumpa, Siya
- Date: 2020
- Subjects: South African fiction (English)
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/167222 , vital:41448
- Description: Creative work portfolio.
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- Date Issued: 2020
The characteristics and trends of rainfall on sub-Antarctic Marion Island and associated air circulation patterns
- Authors: Mapuka, Fortunate Nomsa
- Date: 2020
- Language: English
- Type: Thesis , Masters , MSc(Geography)
- Identifier: http://hdl.handle.net/10353/18698 , vital:42725
- Description: Marion Island (46°54ʹS, 37°45ʹE) located in the Southern Ocean possesses one of the most oceanic climates on earth and sensitive to climate change. Climatologically, the sub-Antarctic is inadequately represented in the climate literature and this research therefore attempts to establish the recent changes that have occurred on Marion Island with regards to annual rainfall totals, monthly rainfall, rain days and non-rain days during the period from 1980 to 2018. This study found that annual rainfall has decreased by 24% from 2196.7 mm to 1678.57 mm from 1980 to 2018 and that the last decade (2010-2018) is the driest on record. The decrease in annual rainfall on Marion Island can be directly linked to the decreases recorded in monthly and daily rainfall. Rainfall in autumn has reduced by 35% over the last 40 years and the decrease in autumn rainfall is in part directly related to an increase in anticyclonic air circulation during which Marion Island is not influenced by any mid-latitudinal depressions. The frequency of rain days measured on Marion Island significantly decreased. Daily rainfall measuring less than 5 mm of rain a day contribute 50% of the total number of rain days. However, these high frequency low depth rainfall days contribute very little rainfall to annual totals. On Marion Island rain days that measure 10 mm and above contribute 65% of the total annual rainfall and it is also these type of high magnitude rain days that have significantly decreased since 1980. Multi-day consecutive rain events contribute the greatest proportion of rainfall to the annual rainfall totals (~40%). Linear statistics shows that the contribution to rainfall amount from these multi-day rainfall has halved since 1980. The frequency of non-rain days and consecutive non-rain days have significantly increased. The increased frequency of anticyclonic air circulation over Marion Island and the decrease of the traveling low-pressure systems affecting Marion Island are the probable cause of the increase in non-rain days. It is suggested that this increase in consecutive non-rain days has the most significant impact on the island’s biodiversity and landscape
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- Date Issued: 2020
The current nature of intra-regional trade in the proposed tripartite free trade area
- Authors: Chibuta, Chisengele
- Date: 2020
- Subjects: Customs unions -- Africa, Southern -- Economic integration , Africa, Southern -- Economic policy , Africa, Southern -- Economic integration , Africa, Southern -- Economic conditions , Tripartite Free Trade Area , Free trade -- Africa, Southern
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/146744 , vital:38553
- Description: This thesis examines and analyses the current nature of intra-regional trade between member states of the proposed Tripartite Free Trade Area in order to contribute to an understanding of the potential for intra-regional trade within the region to increase. Trade Complementarity Indexes were used to determine how well the structures of the three founding blocs’ major imports and exports match. The results show that there is a high degree of trade complementarity in the trade of the top 5 major products traded between the regional groups. With the proposed TFTA in place, high trade complementarity could lead to increased trade between the regional groups. Trade Intensity Indexes were used to determine how intensively the three founding blocs trade with one another. Results from the indexes help determine the extent to which the blocs currently view each other as important trading partners and the implications of this for the proposed TFTA. Results show that EAC and SADC as well as EAC and COMESA viewed each other as significant trading partners while SADC and COMESA did not for the majority of the years from 2001 to 2018. With the TFTA in place, intra-regional trade could be strengthened among the members who currently trade intensively because tariffs between them would be progressively eliminated as required by the TFTA Agreement. Revealed Comparative Advantage Indexes were used to gain insights on whether member states have any comparative advantage in their top 5 exports. Results from the indexes were used to determine whether member states have comparative advantage in similar or dissimilar major exports and the implications of this for the proposed TFTA. Results show that member states have revealed comparative advantage in similar products and these products present opportunities for joint-production among member states as well as sectors for product development once the proposed TFTA is in place. Revealed Trade Barrier Indexes were used to gain insights into the extent of ease of market access into each regional bloc’s market. Results from the indexes indicate whether major products imported from each other receive possibly discriminatory or preferential treatment. The results indicate that the majority of the top 5 imports sourced from each region receive preferential treatment. This indicates that there is ease of market access for the top 5 imports sourced from each other and this could promote increased intra-regional trade among member states in these product categories because tariff and non-tariff barriers to trade will be progressively eliminated once the TFTA is in place.
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- Date Issued: 2020
The development of a framework to facilitate an increase level of self employment mongst the rural youth by promoting increased level of entrepreneurial intent
- Authors: Lindoor, Jillian
- Date: 2020
- Subjects: Youth-- Employment -- South Africa -- Eastern Cape , Rural youth -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/49878 , vital:41812
- Description: Natural resources and unique livelihoods within rural areas could be transformed into investments that would attract affluent urban groups and benefit the wider community,reduce unemployment and create self-employment among the youth. However limited employment opportunities, ongoing failure of local development projects, low level of self-acknowledge conviction amongst the rural youth to set up new business ventures is low exists. These issues that serve as the motivation for this research, are evident in the Dr Beyers Naude Local Municipality (BNLM) in the Eastern Cape of South Africa. These issues increases poverty, alcohol and substance abuse. It is important to find a solution to the problem and develop the local economy, increase employment, reduce poverty and assist in contributing to the millennium goals as set out by the United Nations. The research objective of the study is therefore to investigate what methods can be implemented to facilitate an increase in the level of self-employment amongst the rural youth by promoting an increased level of entrepreneurial intent.
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- Date Issued: 2020
The development of a project management body of knowledge model for Vodacom in the eastern region of RSA
- Authors: Alley, Andre
- Date: 2020
- Subjects: Cell phone services industry -- South Africa , Project management Knowledge management Organizational learning
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/50338 , vital:42110
- Description: The purpose of this research was the development of a project management body of knowledge model for Vodacom in the Eastern Region of the Republic of South Africa (RSA). As a result of a recent increase of complaints regarding projects delivered by Vodacom Eastern Region. The research started with a structured literature review, followed by a qualitative case study research design using embedded units of analysis, providing useful insights in sustainable project management in Vodacom Easter Region, RSA. The outcome of the research was in the form of a sustainable project management body of knowledge model for Vodacom in the Eastern Region of RSA, which highlighted five focus areas, namely; team structure, project organisational structure, stakeholder management, attributes of team members, communication and information technology enablers. The study concluded with practical recommendations for a relevant and sustainable project management model under the five focus areas.
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- Date Issued: 2020
The development of teacher leadership: a formative interventionist study in a semi-urban secondary school of Khomas region in Namibia
- Authors: Shilongo, Justina
- Date: 2020
- Subjects: Educational leadership -- Namibia , Educational leadership -- Namibia -- Case studies , Education -- Namibia
- Language: English
- Type: text , Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/144923 , vital:38392
- Description: Historically the education system in Namibia was shaped by the policies of the apartheid ideology (Amukugo, 1993). During that time, authority and responsibility were centralised and teachers were not part of the decision making process. By then, most people expected to be told what to do and would not initiate something on their own, a culture inherited that even exists today. In addition, opportunities were not given to teachers to develop as leaders. While Namibians have this history on record, the fact remains that the way in which apartheid laws were put in place, the ideological basis of the policy of apartheid and its impact, was not supportive of the ideas of democracy that Namibia is advocating for today. Despite a number of series of policy guidelines and directives issued to guide the development of a democratic culture in the education sector, less is happening about the leadership of teachers in schools. This stimulated me to conduct an activity theoretical interventionist research, aimed at exploring what opportunities there are for teachers to develop as leaders. This study is a case study, operating from a generative standpoint. The study was conducted in a semi-urban secondary school in Windhoek, Khomas Region, Namibia. The study took a formative intervention approach as it sought to bring about change to practice in the case study school and also to contribute to a body of knowledge in the field of study. This qualitative study employed interviews, observations, document analysis and WhatsApp messaging as data generation tools. Crystallised data revealed multiple realities that demonstrated meaningful and trustworthy data. To analyse data the study employed inductive and abductive analysis to make data meaningful to the reader. Thus, to explore teacher leadership development in a semi-urban secondary school, Change Laboratories Workshops was used as a method to gather and analyse data, as underpinned by 2nd generation CHAT. Grant’s (2017) model of teacher leadership was also used to analyse the data and indicate where teacher leadership roles were mostly visible from all four zones. The findings revealed that there were different understandings of the notion of teacher leadership. It was understood as the possession of certain qualities, a managerial role, an involvement in the decision-making process and a form of social responsibility. It was also revealed that teachers led in all four zones (Grant, 2017b), however participants were not active in all the roles. High participation was noticed in zone one, within the classroom; zone two, leading in curricular and extra-curricular activities and zone four, leading beyond the school into the community. This study explored teacher leadership development and at length identified the conditions that constrained and enabled teachers to develop as leaders in a secondary school. The factors that constrained teacher leadership in the case study school were: lack of time, demanding workloads and other commitments, lack of interest in extramural activities and SMT support for initiatives. Fear and unwillingness to take on leadership roles, narrow views on leadership and ingrained traditional leadership structures, limited leadership capacity building initiatives and the absence of clear educational policies on teacher leadership were also identified. The high involvement in zone one, two and four were attributed to some mechanisms the school put in place to promote teacher leadership, such as through various committees set-up, as well as a culture of mutual care and love. During the change laboratory workshops, teachers opted to be trained in leadership-related matters and to revive the CPD committee.
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- Date Issued: 2020
The digital and the hyperreal, with reference to artwork by Signe Pierce and Lauren King
- Authors: King, Lauren Pascal
- Date: 2020
- Subjects: Women in art , Femininity in art , Figurative art , Cyberspace -- Social aspects , Feminine beauty (Aesthetics) , Online identities , Photo-realism , Computer art , Virtual reality in art , Reality in art , Art, Modern -- 21st century , Feminist art criticism , Pierce, Signe
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/147939 , vital:38688
- Description: This MFA is a visual art critical investigation of digital representations, manipulations, and exploitations of feminine figures in cyberspace. The particular focus of this study is centred on the work of self-titled reality artist Signe Pierce, as well as my own practical body of work: The Digital Feminine. Case studies of Pierce’s practice include Big Sister (2016), Halo (2018), American Reflexxx (2013) and Reality Hack (2016). Through these case studies I examine the nature of identity formation online as underscored by notions of performativity as well as arguments for the use of feminine aesthetics as feminist critique, specifically through the use of the ‘Venus Flytrapping’ method. Jean Baudrillard famously theorised the hyperreal and the simulacra, claiming that human experience is a simulation of reality1. My MFA thesis addresses contemporary concerns relating to issues of reality, perception, the gaze, and identity in an increasingly virtual world. The 20th century witnessed massive changes in technology, and its subsequent commercialisation marked new territories for mass media, politics, entertainment, social life, and the art world. Avant-garde modern art movements shattered previously held standards of traditional artistic production, thus ideas surrounding the ‘art object’ and the role of artists themselves were fundamentally changed. In a postmodern world where nothing is sacred and life is experienced through the simulacra of the screen, the hyperreal takes over. I investigate how real-world socio-political issues, particularly those related to gender, transcend into the digital realm of cyberspace through discussions of Donna Harraway’s ‘cyborg feminism’ and Judith Butler’s ideas of gender performativity, as well as Erving Goffman’s ideas of everyday performativity. My final body of work for the professional art practice component of this MFA is realised in the form of an immersive installation that straddles the virtual and the real. Influenced by digital and hyperreal aesthetics (such as VapourWave), this installation also explores various expressions of femininity that an individual can express both online and in real life.
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- Date Issued: 2020
The digital rhetoric of addressing rape culture: “official” and “unofficial” arguments at Rhodes University
- Authors: Jones, Megaera
- Date: 2020
- Subjects: Rape in universities and colleges -- South Africa -- Makhanda , Universities and colleges -- Administration -- South Africa -- Makhanda , Communication in higher education - South Africa -- Makhanda
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/142621 , vital:38096
- Description: South Africa is overwhelmed with high levels of sexual violence and institutions of higher education in South Africa are not exempt from this. How higher education stakeholders have responded to the call to address rape culture on campuses has been at the centre of much attention, especially publicly on online communicative spaces. Drawing on contemporary rhetorical theories, informed by a feminist poststructuralist perspective, this study sought to explore how constituents at Rhodes University were discussing how rape culture should (and should not be) addressed on campus. Using a rhetorical analysis, this study collected and analysed online public data from ‘official’ (institutionally sanctioned) and ‘unofficial’ (institutionally independent) communication platforms, following the 2016 rape culture student-led protest at Rhodes University. In analysing and interpreting the data from the ‘official’ sites, four major themes of discussion were evident. These rhetors argued that rape culture is a societal issue, requiring collective responsibility and effort in countering it, and that any approach to do so must abide by the bounds of the law. The University’s commitment, and continued investment to address rape culture on campus were repeatedly stated; as well as, the use of external ‘supportive’ messages that bolstered the reputation, efforts, and actions of the institution. On the ‘unofficial’ sites six broad patterns of discussion were evident. These ‘unofficial’ rhetors embodied the rape culture on campus, perceiving its effects as threatening to the physical body, which led to the adoption of the argument that rape culture needs to be ‘fought’ through physical action and support. Narrow law and order approaches were contested, and the need for a victim-centred approaches were prioritised. Additionally, doubt and suspicion were cast onto the institutional management/leadership, and the University (management/leadership body) were perceived as having ‘failed’ to address rape culture adequality. Considering this ‘failure’, a divisive rhetoric argued that the ‘fight’ against rape culture should continue, despite, and separate from, the institutional body. These findings revealed how the divisive positions these various stakeholders took created a volatile climate between University management/leadership, staff, and student. I argue that such division will continue to undermine any meaningful efforts to counter rape culture on the University campus; underscoring the difficulty, and ambiguity, that comes with attempting to address rape culture on higher education campuses. This necessitates how important it will be for scholars to research, and continue researching, the ways in which a rape culture, and the various approaches which attempt to counter it, are understood.
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- Date Issued: 2020
The distiction between debt and equity from an income tax perspective
- Authors: Duna, Nomfundo
- Date: 2020
- Subjects: Income tax -- South Africa
- Language: English
- Type: Thesis , Masters , MCOM
- Identifier: http://hdl.handle.net/10948/47791 , vital:40375
- Description: The debt bias gives rise to real and disadvantageous consequences for many jurisdictions. South Africa is by no means any safer from its dilutive and evasive effect. This bias in favour of debt arises as a result of the difference in the tax treatment of debt and equity which is found in the South African tax legislation. At the centre of the difference in tax treatment is that under the domestic tax legislation, interest incurred on debt is deductible to the extent that the debt was used to fund income generating assets which dividends payable to equity investors is not. From a South African perspective, the classification of a funding as debt or equity funding for tax purposes is not exhaustively dealt with within the tax legislation as it is not always that these terms are defined in the tax legislation. In some instances, common law is relied upon to classify funding as debt or equity funding. Furthermore, this classification and the resultant tax treatment of funding as either debt or equity becomes even more complicated when you consider the various tax avoidance mechanisms that taxpayer corporations use to take advantage of the debt bias. Tax avoidance mechanisms such as the uptake of excessive debt to increase interest deductions and the use of hybrid debt instruments has necessitated the inclusion of targeted anti-avoidance provisions that operate to either reclassify the nature of the funding or the return on such funding, or in some instances deny interest deductions. These targeted anti-avoidance provisions contain definitions of the type of funding that they apply to. In the South African context, the South African tax legislation contains provisions in respect of anti-excessive debt rules contained in section 23M and 23N as well as hybrid instruments contained in sections 8E,8EA, 8F and 8FA that aim to counter the extent to which taxpayers exploit the debt bias to avoid tax.
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- Date Issued: 2020