Cape Peninsula University of Technology
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Novel approaches to improving domestic solar panel energy yields in Sub-Sahara Africa
No full textThesis (DTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2017.This thesis contains innovations that could help homesteads in sub-Sahara Africa (SSA) to ‘harvest’ more energy from flat solar energy collection surfaces. The thesis makes the assumption that universal resolution of energy poverty is a long term issue – and may not realistically be achieved using the traditional electrification route of: Fossil fuel/Hydro potential → electricity → transmission/distribution → paid for/free usage. Using a combination of literature search, Transient System Simulation (TRNSYS) modelling and experimental validation, the thesis notes the bi-hemispherical tropical location of most of the region and the abundant solar resource. It therefore advocates extensive use of the resource at home level for both electricity generation, and fluid heating/preheating purposes.
Using mathematical models, the thesis critically examines relationships among energy incidence, transformation and yield from a flat surface for both Photovoltaic (PV) and Solar Thermal (ST) usage. It suggests the first set of innovations for the region: the two azimuths installations. The second set uses TRNSYS and Operations Research (OR) modelling to optimise selection of PV equipment meeting a starter–home’s energy loads throughout the region. Recommendations for both sets of innovations are presented in the form of colour coded maps. The third innovation in the thesis is the patented gravity driven, hydro-mechanical solar tracker, a novel solar tracking device in three different operation and control modes. In summary, one patent, 4 journal papers and 5 peer-reviewed international conference papers comprise the work
Determination of the head loss coefficient of closely spaced pipe bends
No full textThesis (MTech (Mechanical Engineering))--Cape Peninsula University of Technology, 2017.Space limitation in ships and the complex pipe layouts in chemical, mineral and food processing plants lead to the employment of closely spaced bends. The limited information regarding the head loss coefficient of pipe bends orientated as bend-spacer-bend has led pipeline designers to treat them as isolated bends with the same loss coefficient. Thus, to calculate the head loss in the piping system would simply involve summing the head loss coefficient of bends and neglecting their configuration. This practice causes inaccurate computation of head losses in the system.
In this study a computational model is developed for the head loss coefficient of closely spaced pipe bends. This is then supported by experimental verification. A more accurate but still simple and easy to use empirical correlation is derived. The empirical correlation is established and the data presented under isothermal conditions for turbulent flows in a range 7.3x104 ≤ Re ≤ 5.8x105 and a spacing ratio of 1D ≤ L/d ≤ 10Dand curvature ratio of 3 ≤ rc/d ≤ 5. Using ANSYS® CFX® 11, a commercial computational fluid dynamics (CFD) package, the fluid domain representing two 900 smooth pipe bends separated by a short pipe was solved and the mechanisms causing the head loss coefficient were explored by using the CFD results to visualise the fluid flow structure/pattern. The computational model was validated by comparing the head loss coefficient of a single bend and the model was found to be sound. The experiments conducted in the built test facility using smooth pipes showed similarities in the trends between the CFD work and the published data and they were to be found have a similar trend. The experiment had shown results that agree to the findings from literature
Employee retention in selected hotels in Cape Town, South Africa
No full textThesis (MTech (Tourism and Hospitality Management))--Cape Peninsula University of Technology, 2017.The hotel sector has been identified as experiencing the largest numbers of employees leaving their jobs within a short period of employment when compared to other sectors of the economy. The large number of employees leaving hotels within a short period of employment is perceived as detrimental towards business’ success. This research is about testing the strength of the relationship between employee retention variables and employee retention in hotels in Cape Town, South Africa. The researcher firstly consulted literature (secondary data) in order to understand the hotel employee retention phenomenon. From the literature findings, the objectives of this research were formulated. The research objectives were built based on the literature findings in order to assess the strength of relationships between employees’ perceptions of employee development, employee compensation, work engagement, good working relationship between line managers and subordinates, long working hours on the one hand; and employee retention in the hotel sector on the other hand.
As the research aimed at testing relationships between variables, a quantitative research method was deemed the appropriate approach. Structured questionnaire surveys, using non-probability sampling, were applied in the form of a convenience approach. Hotels willing to participate in the study were selected, as Cape Town has a large population of hotels. Data for this study was collected over a period of ten months. A bivariate analysis was applied in this research in the form of correlation and Chi-square tests, after descriptive statistics were done. Reliability tests also measured the level of internal relatedness of the variables used to explain employee retention and related constructs. The variables and constructs used in this study were tested for relationships. The major results showed that there are highly significant relationships between employee retention, on the one hand, and employee compensation, employee development, working relationship, work engagement, and working hours, on the other hand
Managing infrastructure risks in information communication technology outsourced projects : a case study at Transnet, South Africa
No full textThesis (MTech (Information Technology))--Cape Peninsula University of Technology, 2017.The balance between the dependency on Information and Communications Technology (ICT) and reducing costs has led to an increase in ICT outsourcing in many organisations. ICT outsourcing has benefits, but organisations have limited knowledge on information security and risks when outsourcing these functions. A lack of information security knowledge or a poor organisational risk culture carries the risk of project failure and security breaches. It is unclear how to manage information risks through the usage of ICT infrastructure risk management when outsourcing ICT projects, and this exposes organisations to ICT security risks. The aim of the study is to explore how a selected transport organisation can manage information risks through the usage of infrastructure risk management when outsourcing ICT projects.
Two primary research questions are posed namely, “what information risks does the ICT department manage when outsourcing ICT projects?”, and “how can the ICT department protect their information through the usage of infrastructure risk management against ICT security threats when outsourcing ICT?” To answer these two questions, a study was conducted at a transport organisation in South Africa. A subjective ontological and interpretivist epistemological stance has been adopted and an inductive research approach was followed. The research strategy was a case study. Data for this study was gathered through interviews (17 in total) using semi-structured questionnaires. Data collected were transcribed, summarised, and categorised to provide a clear understanding of the data.
For this study, forty findings and eight themes were identified. The themes are ICT outsourcing, information risks, costs, ICT vendor dependency, vendor access and management, risk management, user awareness, and frameworks. Guidelines are proposed, comprising six primary components.
The results point to gaps that need to be addressed to ensure that information is protected when outsourcing ICT projects. Measures need to be put in place and communication has to be improved among operating divisions. The findings lead to questions such as, ““how does business create an ICT security culture to ensure that information is protected at all times”, and “does vendor access management really get the necessary attention it requires?” Further studies on human behaviour towards ICT security is needed to ensure the protection of organisations against security risks
The effect of initial pH on surface properties of ferric ion precipitates formed during microbial oxidation of ferrous ion by Leptospirillum ferriphilum in a CSTR
No full textThesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2017.While bioleaching is a proven technology for the efficient recovery of base metals from sulphide minerals, its sustenance is dependent on the continuous availability of ferric ion, Fe3+, in soluble form, in the bioleach liquor. However, the solubility of ferric ion is low at higher pH that it tends to precipitate, resulting in the formation of ferric ion precipitates. The formation of ferric ion precipitates in bio-hydrometallurgy decreases the leaching efficiency by trapping the leached metals in solution through an adsorption mechanism which is not well understood. Although the surface properties of the precipitate could be linked to its metal adsorption properties, there has not been a detailed study that gives any indication or explanation of the adsorption mechanism. Therefore, the aim of this study was to investigate the effect of initial pH on the surface properties of ferric ion precipitate and relate this to the adsorption characteristics of the precipitate for desired metals.
Biooxidation experiments catalysed by Leptospirillum ferriphilum were conducted in a CSTR with a working volume of 1L. The biooxidation experiments were conducted at pH values of 1.3, 1.5, 1.7, 1.9 and 2.2 at a constant temperature of 35 0C for 14 days. The recovered precipitates were characterized by X-ray diffraction, elemental analyses, SEM, particle size distribution (PSD) and zeta potential. Zeta potential measurements were conducted to investigate what role initial pH plays in modifying the precipitate surface charge and what role the surface charge of each precipitate plays in the nature of adsorption of copper ions onto the precipitate surface. The amount of copper adsorbed onto the precipitate was quantified by the magnitude of the change in surface charge after adsorption experiments.
Quantification results showed that the amount of ferric ions precipitates formed increased from 4.31g to 13.26g with an increase in initial pH (from 1.3 to 2.2). The results also showed that significant precipitation of ferric ion occurred during the exponential phase while insignificant precipitation was observed during the stationary phase
The equity composition of employees in a selected provincial government department in the Western Cape, South Africa
No full textThesis (MTech (Public Administration))--Cape Peninsula University of Technology, 2017.In 1994 the newly elected democratic South African government inherited a nation deeply scarred by a history of racial division and social, political and economic inequality. The democratic government was determined to create an environment that felt like home to all, a society that welcomed all and a political environment that catered for all.
The democratic government therefore introduced laws and structures designed to promote the principle of “equity.” Although these have been in force for more than 22 years, statistics indicate that white people continue to receive preference over other racial groups. This study sought to provide an overview of the equity composition of employees in the Department of the Premier in the Western Cape government. “Equity composition” refers to the categories of race and gender invoked by the Employment Equity Act in order to promote equality. The aim was to reach a set of conclusions and make recommendations that might improve the equity composition of employees in the direction envisaged by the legislation.
The researcher has made use of a qualitative research methodology for this study. Unstructured interviews were conducted with twenty research participants purposively selected from the Department of the Premier, and the data gathered from the interviews was analysed using content analysis. The study found that there has been an increase in efforts to accommodate people with disabilities. It recommends that a dedicated training workshop regarding employment equity be designed by the director of the people management practices unit and rolled out throughout the department
Effect of social norms and attitudes towards domestic waste in a selected formal settlement in the Western Cape, South Africa
No full textThesis (MTech (Public Management))--Cape Peninsula University of Technology, 2017.The communities of Khayelitsha face problems with regard to managing waste. Increase on the generation of solid waste in the households by the members of the community; far exceed the townships’ ability and capability for safe disposal. Littering in the township is also a persistent problem, despite various clean–up and anti-litter promotional campaigns and programs introduced by local government, private organizations and other community interest groups. The persistent problem of litter and mismanagement of solid waste in the household should be addressed. The rationale and assumption underpinning this study was that waste management problems are related to social norms and attitude of the people of Khayelitsha. To investigate this phenomenon, the study adopted a qualitative paradigm. 300 heads of household residing in Khayelitsha for more than 5 years were surveyed, and door to door interview questions were conducted in 2016 June. Data from the questionnaire were analysed using Thematic and coding analysis. NVivo software was used to generate frequency tables. The responses to most interview questions were consistent for all categories of respondents and did not vary according to respondents’ background, such as gender, location household size or education. The study showed that social norms and attitudes towards waste minimisation in Khayelitsha are related to the entire waste management operation, and householders in Khayelitsha think similarly. To improve waste management in Khayelitsha the following are recommended:
• Government and business need to consider incentives to minimise waste;
• Government needs to improve waste management service facilities and build recycling centre which are accessible to the community; and
• Government and non-governmental organizations and community members should consider awareness, education and training programs on waste wise management
Online business registration at the Department Of Trade and Industry in the Congo : a normative model
No full textThesis (MTech (Marketing))--Cape Peninsula University of Technology, 2017.This thesis, through the lenses of technology acceptance theory, and considering the lack of online interactivity in service delivery, aimed at proposing a model of online business registration adoption for re-branding the government Department of Trade and Industry (DTI) Congo-Brazzaville. Task-Technology Fit (TTF) and Technology Acceptance Model (TAM) were the underpinning theories with which the study described the social phenomenon: online business registration adoption at DTI Congo-Brazzaville as branding tool. Arguably, in doctoral level, without underpinning theories, research conclusions look speculative. The use of theory to underpin this study was further motivated by its interpretative nature and the interplay between technical and non-technical factors which are involved in the process of technology adoption in service organisation.
To come up with new engagement, and informed from successful implementation of DTI South Africa’s e-governance model, DTI Congo was used as case study; hence the country is known for being at the bottom of the pile when it comes to the ease of doing business ratings. Despite resultant benefits namely increased efficiency, effectiveness and improved service delivery that offer e-governance in making services nearer to citizens and easing the strenuous processes involved in manual operations, not all managers at the DTI Congo advocate the adoption of online business system. The problem is that insufficient advocacy of online business registration enforces the void of re-positioning the organisation vis-à-vis its internal customers (employees) as lean and innovative. The overall research question is: “how does the DTI Congo-Brazzaville intend to improve business registration using online business registration service as a branding tool”? The main objective therefore was to propose online service adoption re-branding and re-positioning DTI Congo-Brazzaville
The barriers and opportunities of resource efficiency and cleaner production within a South African context
No full textThesis (MTech (Business Administration))--Cape Peninsula University of Technology, 2017.This research study investigates how environmental tools such as Resource Efficiency and Cleaner Production (RECP) can contribute to sustaining and supporting economic growth in South Africa. Resource optimisation is crucial when considering the concept of sustainable development. It also contributes to addressing the challenges of global warming and climate change, which in turn threaten industrial growth and sustainability in the long term. The study places emphasis on the barriers that prevent industry from implementing RECP recommendations, and identifies opportunities that could potentially reposition businesses should they consider implementation. It also promotes other sustainability tools that are available through collaboration with international entities, and this could be of great benefit to the South African industry. Factors of unemployment and urbanisation restricts national growth to some degree, hence the study explores how RECP can contribute to job retention by introducing new resource optimisation methodologies for the manufacturing sector, Moreover, it examines the imbalance between the demand as well as limitations of these resources. Through the compilation of data collated from questionnaires completed by industry, government and civil society participants, this study looks at achieving a balance between environmental sustainability and growth. It also looks at aligning this balance with the integration of specific economic and environmental policies, which also includes social aspects. What comes through significantly in this research is the lack of awareness within industry in terms of RECP, as well as the importance of prioritising the uptake of environmental initiatives to ensure that industry is compliant with the stringent policies and legislation designed by government to drive the sustainability process. Consequently the study shows that communication between public and private sector, as well as the awareness raising and marketing of sustainability to consumers need to be improved. An analysis of the various government support mechanisms is conducted, in respect of how industry could potentially leverage growth and drive positive change within their businesses. In addition to RECP, emphasis is placed on other Sustainable Consumption and Production (SCP) initiatives and tools that could possibly entrench sustainable practices and help with their incorporation into their business strategies
Harmonic analysis and effectiveness of mitigation techniques applied to a bipolar HVDC system
No full textThesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2017.High Voltage Direct Current (HVDC) transmission is a safe and efficient technology designed to deliver large amounts of electrical power over long distances with minimal losses and at low costs. HVDC links require converters and filters at both terminal stations. The core component of the HVDC system is the power converter that connects the DC and AC systems together. The conversion from AC to DC, and vice versa, is achieved mainly through electronic switches called thyristors. The thyristor-based Line Commutated Converter (LCC) is a mature and trusted technology for HVDC transmission throughout the world.
HVDC converters are bidirectional and can function in either rectification (AC to DC) or inversion mode (DC to AC). This is achieved when the voltage polarity across the converter gets swapped by the controllers, because current cannot change its direction in thyristors.
In this thesis an analytical model of the HVDC converters is developed in the frequency domain by modelling it in DIgSILENT. The objective is to study the harmonics induced to the AC side from HVDC converters. Therefore, it is important in the real world to understand the principles, what causes harmonics to be generated in HVDC and transferred to the HVAC system.
The objective of this thesis is to investigate the effectiveness of mitigation techniques used, on how they reduce harmonics by keeping these harmonic levels within specified values admissible by international standards (e.g. IEEE, etc)