Development of a biocontrol agent, Lecanicillium attenuatum (Zare & Gams), of wheat leaf rust (Puccinia triticina Eriks.)

Master of Science in Plant Pathology. University of KawZulu-Natal, Pietermaritzburg, 2018.Abstract available in PDF file

Protection-based Distributed Generation Penetration Limits on MV feeders - Using Machine Learning

The rise of disruptive technologies and the rapid growth of innovative initiatives have led to a trend of decentralization, deregulation, and distribution of regulated/centralized services. As a result, there is an increasing number of requests for the connection of distributed generators to distribution networks and the need for power utilities to quickly assess the impacts of distributed generators (DGs) to keep up with these requests. Grid integration of DGs brings about protection issues. Current protection systems were not designed for bi-directional power flow, thus the protective devices in the network lose their ability to perform their main functions. To mitigate the impact of distributed generation (DG), some standards and policies constrain the number of DG that can be connected to the distribution network. The problem with these limits is that they are based only on overload and overvoltage, and do not adequately define the DG size/threshold before the occurrence of a protection issue (NRS 097-2-3). The other problem with distributed generation is the vast difference in the technology, location, size, connection sequence, and protection scheme requirements which results in future DG network planning inadequacies – The Network DG Planning Dilemma. To determine the amount of DG to connect to the network, a detailed analysis is required which often involves the use of a simulation tool such as DIgSILENT to model the entire network and perform load flow studies. Modelling networks on DIgSILENT is relatively easy for simple networks but becomes time-consuming for complex, large, and real networks. This brings about a limitation to this method, planning inadequacies, and longer connection approval periods. Thus, there is a need for a fast but accurate system-wide tool that can assess the amount of DG that can be connected to a network. This research aims to present a technique used for calculating protection-based DG penetration limits on MV networks and develop a model to determine medium voltage opportunity network maps. These maps indicate the maximum amount of DG that can be connected to a network without the need for major protection scheme changes in South Africa. The approach to determining protection-based penetration limits is based on supervised machine learning methods. The aim is to rely on protection features present in the distribution network data i.e. fault level, Inverse Definite Minimum Time (IDMT) curve, pick-up current settings, Time Multiplier Settings (TMS), calculated relay operating times and relay positions to see how the network responds at certain DG penetration levels (‘actual' relay operating times). The dataset represents carefully anonymized distribution networks with accepted protection philosophy applied. A supervised machine learning algorithm is applied after nontrivial data pre-processing through recommendation systems and shuffling. The planning dilemma is cast into three parts: the first part is an automated pattern classification (logistic regression for classification of protection miscoordination), the second part involves regression (predicting operating time after different levels of DG penetration), and the last part involves developing a recommendation system (where, when and how much photovoltaic (PV) DG will be connected). Gradient descent, which is an optimisation algorithm that iterates and finds optimal values of the parameters that correspond to the local or global minimum values of the cost function using calculus was used to measure the accuracy of each model's hypothesis function. The cost function (one half mean squared error) for the models that predict ‘actual' relay operating times before DG penetration, at 35%, 65%, and 75% DG penetration converged to values below 120, 20, 15, and 15 seconds2 , respectively, within the first 100 iterations. A high variance problem was observed (cross-validation error was high and training error was low) for the models that used all the network protection features as inputs. The cross-validation and training errors approached the desired performance of 0.3±0.1 for the models that had second-order polynomials added. A training accuracy of 91.30%, 73.91%, 82.61%, and a validation accuracy of 100%, 55.56%, 66.67% was achieved when classifying loss of coordination, loss of grading and desensitization, respectively. A high bias problem was observed (cross-validation error was high and training error was high) for the loss of grading classification (relay positions eliminated) model. When the models (horizontal network features) were applied to four MV distribution networks, loss of coordination was not predicted, the loss of grading model had one false positive and the de-sensitization model had one false negative. However, when the results were compared to the vertical analysis (comparing the operating times of upstream and downstream relays/reclosers), 28 points indicated a loss of coordination (2 at 35%, 1 at 65% and 25 at 75% DG penetration). Protection coordination reinforcements (against loss of grading and desensitization) were found to be a requirement for DG connections where the MV transformer circuit breaker TMS is between 0.5 and 1.1, and where the network fault level is between 650 and 800A. Distribution networks in affluent neighbourhoods similar to those around the Western CapeSomerset West area and Gauteng- Centurion area need to be reinforced to accommodate maximum DG penetration up to the limit of 75% of the After Diversity Maximum Demand (ADMD). For future work, the collection of more data points (results from detailed analytical studies on the impact of DG on MV feeders) to use as training data to solve the observed high variance problem is recommended. Also, modifying the model by adding upstream and downstream network features as inputs in the classification model to solve the high bias problem is recommended

A critical analysis of the income tax implication of income from illegal activities in South Africa

Moneymaking schemes such as prostitution, drug dealing, fraud, corruption, pyramid schemes and the sale of counterfeit goods have been around for years. The taxing of these transactions/schemes has become a contentious issue. It has recently been reported in the press that SARS has lodged a claim for R183 million in income taxes against the estate of the slain mining magnate, Brett Kebble, in respect of the R2 billion allegedly stolen by him from the mining companies of which he was a director.4 It is further reported that the Master of the High Court has rejected the claim on the grounds that the amounts on which SARS sought to levy tax constituted money stolen by Kebble, and that stolen money is not subject to income tax. It has been reported that SARS is to take the Master’s decision in this regard on review.5 The Kebble case raises an interesting and unresolved tax issue and, in view of the large sum at stake, it may be a case that will go all the way to the Supreme Court of Appeal and bring long-overdue certainty to the law. The Income Tax Act No. 58 of 1962 (the Act) is of no assistance in determining the issue. Section 23(o) states that payments that are illegal in terms of Chapter 2 of the Prevention and Combating of Corrupt Activities Act No. 12 of 2004 or that constitute a fine or penalty for any “unlawful activity carried out in the Republic or in any other country if that activity

How climate change education is hurting the environment

Fikile Nxumalo writes about Planet Texas 2050 and how climate changes will negatively impact students in an article published in 2018.Office of the VP for Researc

Municipal boundary demarcation in South Africa: processes and effects on governance in traditional rural areas

Includes bibliographical references.This research adopts a case study approach to investigate disputes involving municipal boundaries in rural communities under traditional authority. Further, a multiple case study approach is used to expose in-depth understanding of these disputes. The causes of the disputes are investigated and the processes of municipal demarcation and boundary dispute resolution are analysed against a number of frameworks such as the goals of good governance in land administration, management paradigm, rights, restrictions and responsibilities, Kotter's eight stages of change management, and 7Es performance measurement frameworks. From this critique, conclusions are drawn about the municipal demarcation processes and improvements are recommended. The study finds that the frameworks and tools applied are suitable for the analysis and evaluation of the municipal boundary demarcation process. The main findings indicate that several municipal demarcations negatively affected service delivery and threatened the role of traditional leaders

Exploring Grade 7 isiZulu First Language learners’ attitudes towards isiZulu in a multiracial primary school.

Masters Degree. University of KwaZulu-Natal, Durban.This study aimed at exploring grade 7, isiZulu first language learners’ attitudes towards isiZulu in a multiracial primary school so as to understand and explain the grade 7, isiZulu first language learners’ attitudes towards isiZulu, in a multiracial primary school. Two research questions were answered namely: What are grade 7 isiZulu first language learners’ attitudes towards isiZulu in a multiracial primary school? What influences the grade 7 isiZulu first language learners’ attitudes towards isiZulu in a multiracial primary school? The study took place in a multiracial primary school in Durban central circuit, in uMkhumbane ward, under the uMlazi district. To answer the critical questions, data was triangulated by using two research instruments, namely; face-to-face semi-structured interviews and open-ended research questionnaires. The study was a case study design which sourced data from a group of 8 learners learning isiZulu (their first language) in a multiracial school context. The study was a qualitative study where an interpretive paradigm was adopted because the participants were interacted with in their natural environment; the school. Purposive sampling was used in selecting eight learners as the participants in this study. The study was framed on two theoretical frameworks, i.e. attitude and bilingualism theories. Data analysis proceeded by way of categorising data into themes that gave rise to sub-themes. In making sense of data generated, this study applied attitude and bilingualism theoretical frameworks when I was analysing data. The findings indicated that some learners had negative and others had positive attitudes towards isiZulu. Those learners with negative attitudes regarded English as a better language. It was recommended that a study exploring isiZulu second language learners experiences in learning isiZulu be conducted in a multiracial primary school where isiZulu is compulsory. Studies in multiracial primary schools where isiZulu is a compulsory subject must be conducted. Experiences of non-isiZulu language speakers must be targeted towards isiZulu speakers. Learners who do not comprehend isiZulu as it is not their first language must be granted the opportunity of receiving extra lessons. Further, schools should create opportunities for learners to communicate in isiZulu even outside the classroom environment

The influence of place and communicated identity on place image and attractiveness of the City of Johannesburg

A research report submitted to the Faculty of Commerce, Law and Management, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Management of Strategic Marketing, Johannesburg, 2016Place branding is defined as the application of marketing techniques and activities, to differentiate and attract interest to promote the social and economic growth of cities, regions and countries. If marketers are to market their respective places effectively, they need to get a sense of the key characteristics that make up a place identity, with particular attention paid to what is perceived or understood as the image. The role of local residents is emphasised in the process of identifying the key attributes that comprise the identity and image of a place. The purpose of this research is to establish the identity of the City of Johannesburg from the perspective of stakeholders responsible for branding the metropolitan and to investigate the perceptions and image of the metropolitan by local residents. The research methodology adopted was a mixed method approach. Semi-structured in-depth interviews were conducted with destination marketing practitioners and the results were content analysed to identify key themes. The quantitative study sought to investigate the perceptions and image of the City of Johannesburg held by local residents using a structured questionnaire. The questionnaire consisted of questions relating to views on place identity, place image and communicated identity. Structural equation modelling was employed in the study for the purpose of analysing the quantitative data. Given the common brand associations made by practitioners and local residents interviewed, one can conclude that the City of Johannesburg is fundamentally South Africa's business hub and associated with opportunities and these associations are unlikely to change and will stay constant as the City goes through various growth cycles. The multi-faceted image of the City of Johannesburg was demonstrated by the different responses elicited from marketing practitioners and local residents. The crime association image does not bode well for the metropolitan and concerted ii efforts are required from all stakeholders involved in marketing the City to deal with the city's negative imageGR201

Perspectives and experiences of female traders in securing a livelihood in the Warwick Market, Durban.

Masters Degree. University of KwaZulu-Natal, Durban.Informal trading serves as a survivalist strategy used by women across South Africa to sustain their livelihoods. Informal trading has grown at a fast rate due to the lack of employment opportunities in both the private and public sector. Informal trading is predominated by black women who are driven into the informal economy as a result of desperation to work in order to financially support themselves and their families. Women often migrate from the rural areas to the urban areas to seek employment opportunities. The poor are usually attracted to the urban areas due to opportunities available. However, due to the lack of education they find themselves involved in informal trading. Informal trading allows for women to sustain their livelihoods and be empowered as they are able to be independent. Informal traders generate an income through the exchange of goods alongside streets and sidewalks. The aim of this study was to shed insights into informal trading as a livelihood strategy amongst female traders. The study draws on qualitative data from semistructured interviews. In total there were 15 interviews conducted with females who were informal traders at Warwick Junction Market. The main reason women started informal trading was to eradicate poverty and to be able to financially provide for their families. This study found that informal traders’ daily working conditions were a challenge. Most traders did not have access to running water and properly sanitized toilets. Weather conditions such as the rain were found to be the biggest challenge, when it rained traders get wet alongside their goods. Despite the challenges, female traders continue to persevere as they are breadwinners and their families in the rural areas are highly dependent on them for survival. In order for informal traders. It can be suggested that the challenges informal traders face in securing their livelihoods were challenges that could be solved if Municipality officials would interact and work alongside informal traders

Business rescue: a delay tactic for liquidation?

Masters Degree. University of KwaZulu-Natal, Durban.No abstract provided

A framework for an optimized capital structure for state-owned natural monopolies

Research report submitted to partially fulfill the Master of Management in Finance and Investments to the Faculty of Commerce, Law and Management at the University of Witwatersrand March 2017This study empirically examines whether the capital structure for natural monopolies (parastatals) dynamically responds to macroeconomic conditions. It further examines whether the balance sheet channel theory holds for this industry sample. The study adopts a double sampling approach from the population of water boards in South Africa (SA), which raise their capital in open financial markets. A quantitative research approach is adopted with a descriptive design to achieve relevant deductions. Panel techniques are used in the descriptive design for the regressions. The study finds that leverage partly dynamically responds to macroeconomic conditions. Furthermore, the evidence shows that inflation is an exception that has no significant relationship with leverage. The balance sheet channel theory is found to hold for water boards that access capital in open financial markets. Specifically, empirical evidence shows that changes in the interest rate have a delayed impact on the companies’ characteristics, including capital structure. Overall, our evidence suggests that water boards in SA need to consider the benefits of linking financial policies to the business cycle and that their policies should consider the delayed effect of interest rate changes.MT201