Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Horticulture in the Faculty of Applied Sciences at the Cape Peninsula University of Technology, 2012 / This article based thesis includes two individual studies evaluating the role of silicon (Si) in mitigating the negative effects that are associated with sodium chloride (NaCl) induced toxicity in lettuce (Lactuca sative L. 'Eish!').

Mini Thesis submitted in partial fulfilment of the requirement for the degree of MAGISTER TECHNOLOGIAE: BUSINESS ADMINISTRATION in the FACULTY OF BUSINESS at the CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2012 / This research study assesses the impact of fluctuating interest rates on the credit card spending habits within a leading South African food retailer by determining whether a relationship exists between interest rates and credit card spending and whether this relationship is significant. Although there are many factors that influence consumer use of credit cards such as fuel prices, cost of food and affordability, interest rates play a role in the decision making process whether to purchase on credit or not. To assess the effect of interest rates on credit card spending within the food retailer, turnover data by tender type were obtained from the retailer and were compared to interest rate changes as announced by the Governor of the South African Reserve Bank. By using non-parametric Spearman Rank Order Correlations the nature and significance of the relationship between interest rate data and tender data was determined by using a confidence level of 95 %. Customer surveys were conducted within the Cape Town area to understand the effect interest rates have on credit card usage, what the preferred methods of payments are, retailer preference, shopping frequency, average grocery spend and the perception of interest rate fairness of respondents. A total of 213 completed questionnaires were analysed and significant correlations between various variables were determined and discussed. The result of the data analysis revealed that a significant adverse relationship exists between interest rates and credit card spending within the selected food retailer. Key Words: Credit Card, Turnover, Interest Rates, Food Retailer, Retail Food Sector, Average Transaction Value, Transaction Volume, Tender Type, Consumers, Customers, ShopriteCheckers, Spar, Pick n Pay, Woolworths, South African Reserve Bank, SARB

Thesis presented in ful lment of the requirements for the degree of Magister Technologiae in Electrical Engineering at the Cape Peninsula University of Technology, 2013 / The power system is essentially one of the most critical subsystems to any satellite, without some form of power system a satellite would simply cease to function. The research within these pages investigates the areas pertaining to satellite power systems with the main focus towards the CubeSat platform. The end objective of this research was the development of a reliable analogue based switch-mode power system for a CubeSat. The research began with an investigation into the CubeSat platform, the space environment and a basic overview of a satellite and its systems. The research then focussed on satellite power systems, focussing primarily on satellite power system topologies and switch-mode power systems. Various components and concepts surrounding the satellite power system were investigate and included the photovoltaic (PV) solar cell, batteries, satellite power system topologies, protection concepts and typical CubeSat power systems. The nal part of the literature review included research into typical CubeSat power systems. The space environment complicates the design of satellite systems. The developed electrical power system harnessed electrical power from a PV solar panel by means of a fractional opencircuit voltage (FOCV) based maximum power point tracker (MPPT) with the use of a SEPIC DC-DC converter. The use of a SEPIC DC-DC converter allowed the system to operate at a greater e ciency than could be expected from linear designs. The requirement for an e cient system was important as the heat generated by the power system could bring rise to dissipation issues, resulting in over-heating of various components. The design took into account component sizing, as larger components would be more prone to damage during the high accelerations and vibrations associated with being launched into space. The use of a MPPT allowed the power system to better utilise the available PV solar panel power, by maintaining the PV solar panel near its optimum operating voltage. The design slid between MPPT and voltage regulation to harness as much power as possible while not over-charging the Lithium polymer battery. The power system consisted of battery under-voltage protection as well as over-current protection for the attached payloads and satellite subsystems. The SEPIC DC-DC converter was selected over other SMPS topologies, as this topology could be used in a 1U and 3U CubeSat with a wide variety of PV solar panel cell con gurations. The bene ts of this SMPS topology are due to the SEPIC DC-DC converter's ability to produce an output voltage greater than, less than or equal to the input voltage (National Semiconductor, 2008; Texas Instruments, 2008a). This, along with the operation of the FOCV based MPPT, allowed the power system to be very exible. The designed FOCV based MPPT could be pre-set to di ering PV solar cell technologies due to the adjustable ratio between the maximum power point voltage, Vmpp, and the open-circuit voltage, Voc of the PV solar panel. It was decided not to select a Buck or Boost DC-DC converter based power system as this would limit the exibility of the system. Additionally, the SEPIC DC-DC converter brings with it the ability to isolate the input and output voltage upon shut down. This isolation is due to the SEPIC DC-DC converter's coupling capacitor and this topologies operation as described by National Semiconductor (2008) and Texas Instruments (2008a). The prototype was versatile allowing a wide variety of PV solar cell technologies to be used. The wide operating voltage of the prototype allowed the design to be connected to a series or parallel combination of solar cells with an operating voltage of 3 V to 20 V. The power handling capability of the prototype per solar panel channel allows the design to be applied to a 1 U or 3 U CubeSat given that the channel did not exceed 10 W. All components of the prototype operated without fault, e ectively charging the Li-poly battery safely while protecting payloads and subsystems. The SEPIC DC-DC converter utilised by the MPPT achieved an e ciency of 71 % under full load and with an input voltage of 10 V.

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology, 2012 / In order to effectively determine the occurrences of space weather anomalies in near Earth orbit, a highly sensitive space-grade magnetometer system is needed for measuring changes in the Earth’s magnetic field, which is the aftermath of space weather storms. This research is a foundational work, aimed at evaluating a commercial-off-the-shelf (COTS) high temperature DC SQUID (superconducting quantum interference device) magnetometer, and establishing the possibility of using it for space weather applications. A SQUID magnetometer is a magnetic field measuring in strument that produces an electrical signal relative to the sensed external magnetic field intensity.

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Horticulture in the Faculty of Applied Sciences at the Cape Peninsula University of Technology, 2013 / Cape Flats Sand Fynbos (CFSF) is one of the most poorly conserved vegetation types in the Cape Floral Kingdom, and a large proportion of unconserved land is degraded, primarily as a result of transformation by agricultural, urban developments and invasion by alien plants. Fynbos restoration is one of the most important management interventions, both within the current conservation areas and in any future land remnants acquired for conservation. Many extant remnants are fragmented and isolated, and if successful restoration protocols are found, it may be possible to improve the conservation targets for this critically endangered vegetation type. On old fields, where indigenous soil seed banks have been lost due to alien plant invasion and anthropogenic action, it is essential to reintroduce the longer-lived fynbos components that contribute to vegetation structure, in order to facilitate the progress of the ecosystem on a more natural trajectory. This research is built on an earlier study of optimal ground-preparation treatments for restoring Sand Fynbos to old fields. This former study indicated that fossorial mammals (molerats and gerbils) may occur in dense colonies on old fields and present an obstacle to successful seedling establishment. The project aims to provide protocols for the establishment of indigenous seedlings from harvested seed onto old fields, in order to restore Sand Fynbos vegetation. Different pre-sowing treatments and sowing techniques were tested on large field plots to determine the most efficient protocol. The objectives of the research were: a) to investigate optimal pre-sowing treatments of indigenous seed for restoring degraded Sand Fynbos vegetation in old field sites; b) to investigate optimal sowing techniques on large field plots for restoring degraded Sand Fynbos vegetation in old field sites with depleted indigenous seed banks; c) to provide guidelines and disseminate information on optimal sowing protocols, and their costs, for restoring Sand Fynbos vegetation in degraded areas and old fields. A further component of the research was to calculate the costs of all treatments on a per hectare basis in order to assess the cost-effectiveness of the different options. Several different seed treatments may potentially increase the germination rate and promote fynbos restoration. These are scarifying, smoke, smoke water, chemical, light and temperature pre-sowing treatments. In order to keep the number of treatments (including their interactions) to a manageable level, only soaking in smoke water extract and seed coat scarification with course sand and grit were tested. A seed sample of each species was x-rayed at the Millennium Seed Bank in the United Kingdom, to test for viability in the seed samples, 52 % of the seed collected were empty, a typical indication of wild harvested seed. All species were germinated at 10/25 °C and 16/8 hours light/dark respectively. Scarification had a larger overall germination success, smoke water had very little effect on CFSF species, it is rather that germination is related to temperatures during a fire that result in seed coat splitting. It was recommended that further investigation using more species across the Sand Fynbos vegetation be conducted on pre-germination effects of heat and scarification. The study site had been cleared of woody invasive alien vegetation and additional site preparation included the application of a systemic herbicide to kill undesirable herbaceous weeds, prescribed fire to clear the site of woody debris and destroy weed seeds, and the local control of fossorial mammals (gerbils and molerats) by placing raptor perches and owl nesting boxes around the site. This research found that the use of herbicide shortly after the prescribed fire and once again prior to sowing was successful in controlling herbaceous weeds and the indigenous grass Cynodon dactylon. The challenge to using prescribed burning on old fields was low fuel loads, which resulted in a cool patchy. It is suggested that cutting and spreading of alien plant biomass is tested as a solution, however, the material must be evenly spread across the site and not stacked into piles which can cause excessively hot fires and scorching of the soil. In order to better understand soil conditions across the site, soil samples were collected prior to sowing, to analyse for soil macronutrients, organic matter and pH. It was established that all the excess nutrients added to the site from agriculture and pasturage over the years had leached from the soil. However, the organic matter content of the soil was extremely low and research needs to be done on the organic carbon content of the soils, how these relate to soil micro biota (which species are present and their relationship with CFSF species) and how best to enrich the site with humic matter for restoration and establishment of Cape Flats Sand Fynbos. The field trial was set up in the Blaauwberg Nature Reserve, a random split-plot block design, was replicated five times and used to investigate the selected seedbed preparation and sowing techniques, namely: broadcast sowing onto unprepared seedbed, broadcast with plank embedding of seed onto disked seedbed, broadcast onto disked seedbed and hydro-seed with disked seedbed. Results from the research found that the most successful methods for sowing seeds were the hydro-seeding and broadcast with plank embed. These methods may have provided better contact between the soil and seeds and better protection from predation and wind. Economically the broadcast and embed was better as machinery was more efficient and effective than manual labour. This study recommended that these two methods be combined with the additional planting of rare and threatened species in clumps to determine the benefits and interactions of each technique over the long term.

Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Chemical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2011 / Treatment of waste material from mining and mineral processing is gaining increasing importance as a result of the increasing demand for high purity products and environmental concerns. Supported liquid membranes (SLMs) have been proposed as a new technology for the selective removal of metal ions from a solution. This technology can be described as the simultaneous extraction and stripping operation, combined in a continuous single process unit. Theoretically, the rate of mass transfer through SLM systems could be controlled by three resistances, namely: · Resistance through the feed-side · Resistance through the strip-side laminar layers; and · Diffusion through the membrane. It has been reported that transport resistance in the feed-side laminar layer is controlling. (Srisurichan et al, 2005:186). The objective of this research was to extract copper ions in a TSLM system, evaluate the effect of the feed characteristics on the feed-side laminar layer and determine a relationship between the applicable dimensionless numbers, i.e. Sherwood, Schmidt and Reynolds numbers. A Counter-current, double pipe Perspex bench-scale reactor, consisting of a single hydrophobic PVDF tubular membrane mounted vertically within, was used for the test work. The membrane was impregnated with LIX 984N-C and became the support for this organic transport medium. Dilute Copper solution passed through the centre pipe and sulphuric acid, as a strippant, passed through the shell side. In this test work, Copper was successfully transported from the feed-side to the strip-side and through repetitive results; a relationship between dimensionless numbers was achieved.

Thesis submitted in fulfilment of the requirements for the degree of Master of Technology: Business Information System In the Faculty of Business At the Cape Peninsula University of Technology, 2013 / The South African manufacturing industry landscape has changed due to the pressures of globalisation and liberalisation of trade policy regimes. The structural shift of this industry has led to a global market in which many small businesses in the manufacturing sector find it difficult to compete with competitors for example, in Asian countries. Companies are required to improve their competitiveness by using various strategies such as e-commerce. However, these strategies are changing economics, markets, industry structure, products and services, the flow of products and services, consumer segmentation, consumer values, consumer behaviour and labour markets. An e-commerce strategy could assist small businesses in emerging markets to streamline their business processes in their respective sectors and industries, thus enabling them to enhance their business activities. Yet, literature reveals that most SMMEs do not take full advantage of e-commerce applications in their business activities. A qualitative approach using a case study methodology is used for this research. The researcher adopted models such as the Technology-Organisational-Environmental model, a value proposition model and a key assets model to collect and analyse evidence to propose guidelines for e-commerce initiatives in the selected environment. The findings indicate that SMMEs could improve their performance by establishing formal strategies and structures to increase their worth. This is done by creating e-commerce strategies to fit their organisational goals and objectives. Furthermore, manufacturing SMMEs need appropriate online platforms to transact and build strong relationships with suppliers, customers and partners. In addition, it is essential for SMMEs to establish and monitor quality standards in their e-commerce activities. It was found that the key assets needed by SMMEs in the manufacturing sector could impact their ability to sustain their business activities. Finally, manufacturing SMMEs need to deliver targeted and contextual marketing messages to help influence potential decision makers. This research contributes to the field of e-commerce by providing guidelines which manufacturing SMMEs could use as a starting point, to understand and improve their current e-commerce strategies and sustain their business growth.

To be submitted in fulfilment of the requirements for the degree MASTER OF TECHNOLOGIAE: In Quality In the Faculty of Engineering AT THE CAPE PENINSULA UNIVERSITY OF TECHNOLOGY, 2012 / Over the last decades, due to the lack of safety concern and inadequate quality management in logistical process, it caused unsafe and poor quality of maize products. Thus, this study looks into the key factors that affect maize exports from South Africa in order to improve the logistical processes and reduce the risks involved in the process. The main risks associated with poor traceability and logistical chain management of maize export, as well as issues pertaining to non-conformance to the different food safety standards were explored. Data were collected a group of food business operators (FBO) (n1=127) and food business inspectors (n2=20) through a number of interviews and a self-administered questionnaire. Data were then analysed by using the SPSS-V19 programme to generate descriptive statistical results to determine the specific needs and gaps within the current system as well as providing recommendations on the specific food safety changes pertaining to the maize export industry. The results showed that there is a lack of understanding among role-players regarding FBO legislation. In the comparison of many large companies, there is only a few small role-players adhere to the legislation pertaining to food safety and traceability. This has impacted on the quality of maize products negatively. This strongly suggested that all role-players that handle maize for export must be registered for FBO codes with Department of Agriculture, Forestry and Fisheries. The study also recommended that the Perishable Products Export Control Board (PPECB) should inspect and confirm the legitimacy of the FBO codes that appears on the maize export documentation. Keywords: Quality, food safety, food business operator, maize export, logistical processes, and traceability.

A thesis submitted to the Faculty of Engineering in fulfilment of the requirements for the degree of Master of Technology in Mechanical Engineering 2005 / The objective of this project was to monitor the high temperature creep behaviour of 441 stainless steel. Two different alloys of 441 were investigated; the main difference between them being the Niobium content. Particularly imporlant to the project was how the Niobium content and grain size affected the creep resistance of the material. Creep tests were performed using purpose built constant load creep test rigs. Initially the rigs were not suitable for the testing procedures pertaining to this project. This was due to persistent problems being experienced with regards the reliability and reproducibility of the rigs. After various modifications were made the results produced from the rigs were consistent. Creep test data was used in order to determine the mechanism of creep that is operative within the material (at a predetermined temperature) under a predetermined load. Particular attention was paid to the resulting stress exponents. in order to identify the operative creep mechanism. The identification of the operative creep mechanisms was also aided by microscopical analysis. This analysis was also necessary to monitor how the grain size had altered at various annealing temperatures. Heat treatment was used as a method to alter the high temperature strength and microstructure of the material. Heat treatments were performed at various temperatures in order to determine the ideal temperature to promote optimum creep resistance of 441. All heat treatments were performed in a purpose designed and built high temperature salt bath furnace. The commissioning of the salt bath formed part of the objectives for this project. Sag testing was also conducted, using purpose built sag test rigs. It was necessary to design and manufacture a sag test rig that could be comparable to the industry accepted method of sag testing known as the two-point beam method, as this method is believed to produce inconsistent results. Conclusions have been drawn from the results of the data and from previous research on the subject matter.

Thesis submitted in fulfilment of the requirements for the degree Magister Technologiae: Information Technology in the Faculty of Informatics and Design at the Cape Peninsula University of Technology, 2013 / South Africa can be seen as one of the most advanced democracies on the African continent. Its 1996 constitution and state institutions were developed to enable a representative, deliberative and participative democracy. The legislature is predominant and public participation is expected like the element that legitimates the institutions of the state, their decisions and their initiatives. However, despite the use of ICTs to enhance the process of public participation, there remain profound misunderstandings between the government and its communities; expressed in demonstrations, strikes and other violent protests, as dissatisfaction in public service delivery grows and confidence in the government declines. The problem is that it seems that the potential of ICTs to better the processes of public participation is not fully understood and not fully realised. The aim of the study was to seek out elements helping and hindering the use of Mobile, Web and Social media in public participation in the city of Cape Town. This research endeavour falls under eParticipation research. It considers consultation for law and policy making in the city of Cape Town. It examines its democratic, social and communicational anchors in terms of facilitation and openness to change, on one hand; and it examines Mobile, Web and Social media, in terms of adoption and use for the purpose of public participation on the other hand. The research adopted the Critical Realism philosophical paradigm for its ontology and epistemology. It set out to use existing knowledge, theories and models to work mainly with qualitative data. It followed a qualitative, exploratory, holistic, and cross-sectional approach developing a case study of eParticipation in the city of Cape Town from a triangulation of methods. Data was gathered from literature, documents, in-depth interviews, a focus group and observation of meetings. The data gathered was analysed using qualitative content analysis. The case study analysis followed the structure of the research conceptual model and built the story of the development of eParticipation in the city, bringing together readiness achievements in individual community members‘ perceptions and attitudes to eParticipation, and readiness achievements in local government induced social facilitation of eParticipation. These eParticipation readiness elements were considered direct determinants of individuals‘ intention to participate using Mobile, Web and Social media, and of local government democratic engagement and openness to change, constituting the city‘s intensity of e-participation. That estimate of the intensity of eParticipation provided ground to sketch out it position towards achieving ‗cultural eParticipation‘ for the city of Cape Town. This study has implications for theory, policy and practice: It develops analytical frameworks for assessing and determining the place of eParticipation; and it suggests a map of favouring and hampering elements to eParticipation in the city of Cape Town.