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Thermoluminescence of secondary glow peaks in carbon-doped aluminium oxide

  • Authors: Seneza, Cleophace
  • Date: 2014
  • Subjects: Thermoluminescence , Aluminum oxide , Thermoluminescence dosimetry
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5537 , http://hdl.handle.net/10962/d1013053
  • Description: Carbon-doped aluminium oxide, α-Al₂O₃ : C, is a highly sensitive luminescence dosimeter. The high sensitivity of α-Al₂O₃ : C has been attributed to large concentrations of oxygen vacancies, F and F⁺ centres, induced in the material during its preparation. The material is prepared in a highly reducing atmosphere in the presence of carbon. In the luminescence process, electrons are trapped in F-centre defects as a result of irradiation of the material. Thermal or optical release of trapped electrons leads to emission of light, thermoluminescence (TL) or optically stimulated light (OSL) respectively. The thermoluminescence technique is used to study point defects involved in luminescence of α-Al₂O₃ : C. A glow curve of α-Al₂O₃ : C, generally, shows three peaks; the main dosimetric peak of high intensity (peak II) and two other peaks of lower intensity called secondary glow peaks (peaks I and III). The overall aim of our work was to study the TL mechanisms responsible for secondary glow peaks in α-Al₂O₃ : C. The dynamics of charge movement between centres during the TL process was studied. The phototransferred thermoluminescence (PTTL) from secondary glow peaks was also studied. The kinetic analysis of TL from secondary peaks has shown that the activation energy of peak I is 0.7 eV and that of peak III, 1.2 eV. The frequency factor, the frequency at which an electron attempts to escape a trap, was found near the range of the Debye vibration frequency. Values of the activation energy are consistent within a variety of methods used. The two peaks follow first order kinetics as confirmed by the TM-Tstop method. A linear dependence of TL from peak I on dose is observed at various doses from 0.5 to 2.5 Gy. The peak position for peak I was also independent on dose, further confirmation that peak I is of first order kinetics. Peak I suffers from thermal fading with storage with a half-life of about 120 s. The dependence of TL intensity for peak I increased as a function of heating rate from 0.2 to 6ºCs⁻¹. In contrast to the TL intensity for peak I, the intensity of TL for peak III decreases with an increase of heating rate from 0.2 to 6ºCs⁻¹. This is evidence of thermal quenching for peak III. Parameters W = 1.48 ± 0:10 eV and C = 4 x 10¹³ of thermal quenching were calculated from peak III intensities at different heating rates. Thermal cleaning of peak III and the glow curve deconvolution methods confirmed that the main peak is actually overlapped by a small peak (labeled peak IIA). The kinetic analysis of peak IIA showed that it is of first order kinetics and that its activation energy is 1:0 eV. In addition, the peak IIA is affected by thermal quenching. Another secondary peak appears at 422ºC (peak IV). However, the kinetic analysis of TL from peak IV was not studied because its intensity is not well defined. A heating rate of 0.4ºCs⁻¹ was used after a dose of 3 Gy in kinetic analysis of peaks IIA and III. The study of the PTTL showed that peaks I and II were regenerated under PTTL but peak III was not. Various effects of the PTTL for peaks I and II for different preheating temperatures in different samples were observed. The effect of annealing at 900ºC for 15 minutes between measurements following each illumination time was studied. The effect of dose on secondary peaks was also studied in this work. The kinetic analysis of the PTTL intensity for peak I showed that its activation energy is 0.7 eV, consistent with the activation energy of the normal TL for peak I. The PTTL intensity from peak I fades rapidly with storage compared with the thermal fading from peak I of the normal TL. The PTTL intensity for peak I decreases as a function of heating rate. This decrease was attributed to thermal quenching. Thermal quenching was not observed in the case of the normal TL intensity. The cause of this contrast requires further study.
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  • Date Issued: 2014

The design of a mini-bus interchange for Njoli Square, Port Elizabeth

  • Authors: Nteleza, Simtembile W. J
  • Date: 2014
  • Subjects: Transportation buildings -- South Africa -- Port Elizabeth -- Designs and plans Terminals (Transportation) -- South Africa -- Port Elizabeth -- Designs and plans , Commuting -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MArch
  • Identifier: http://hdl.handle.net/10948/38923 , vital:35013
  • Description: The overarching concept for this thesis is to identify means of architecturally assisting underdeveloped communities reach economic maturity by manipulating existing - or introducing new development methods that contribute to the economic development of a geographical area. In order to demonstrate this, a catalyst programme is identified, namely the Mini-bus transport interchange, which already exists within the township fabric in an underdeveloped state. The programme possesses the potential to fully realize architectural design potential, while introducing new ways of approaching developments in the township and ways of creating harmonious balance between man-made - and natural structures in a community which was systematically designed around rejected natural structures.
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  • Date Issued: 2014

The design of a new passenger terminal for Durban Harbour

  • Authors: Tyson, Dave
  • Date: 2014
  • Subjects: Harbors -- Design and construction Harbors -- South Africa -- Durban -- Design and construction
  • Language: English
  • Type: Thesis , Masters , MArch
  • Identifier: http://hdl.handle.net/10948/38975 , vital:35016
  • Description: Cruise holidays from Durban Harbour to Mozambique and Mauritius have been popular for many years but have increased dramatically in recent years. Due to the encroaching industrial development of the terminals location, the experience of arrival to the current passenger terminal is one of being exported (human trafficking), as opposed to that of going on holiday. This image is enhanced by passengers sitting on cheap plastic chairs while they wait for their number to be called. After which they journey through a series of makeshift partitions before standing in front of a photograph of the ship to have a photograph taken. This causes a rather depressing boarding process and the traveller only begins to experience the holiday vibe once on board the ship.
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  • Date Issued: 2014

The design of a taxi mini-bus transport interchange for central Mthatha, Province of the Eastern Cape

  • Authors: Mcoteli, Jamandile
  • Date: 2014
  • Subjects: Transportation buildings -- South Africa -- Mthatha -- Designs and plans Terminals (Transportation) -- South Africa -- Mthatha -- Designs and plans
  • Language: English
  • Type: Thesis , Masters , MArch
  • Identifier: http://hdl.handle.net/10948/39021 , vital:35017
  • Description: Public transportation, i.e. busses and minibus taxis provide an essential service to the public, especially low-income groups as they service a greater portion of this population, offering several benefits such as accessibility, cost, reduced travel time, etc. The taxi industry, particularly in South Africa was previously highly unregulated and a marginalized public service. However, with the involvement of relevant stakeholders and critical review of the issues involved, a change in that regard is imminent. The focus of this treatise is the design of a multi-modal public transport hub and traders' market in Mthatha in the Eastern Cape, South Africa. The treatise emerges from a concern with the inadequacies related to provisions for public transportation and informal trading in South Africa and the implication of those inadequacies on the urban environment. Firstly, the research attempts to understand the role of transport in South African towns and cities, with specific focus on the spatial urban character of Mthatha in the Eastern Cape, using various literature sources to support theoretic viewpoints. Secondly, it will analyze the essential nature of public transportation hubs in Mthatha and their role within the urban context, achieved through extensive on-site data gathering, field work, interpretation and analysis. Thirdly, it will explore and resolve the architectural issues involved in the design of a new multi-modal transport hub and traders' market in the town of Mthatha through exploration of precedents within the discourse. An investigation of all the regulations, guidelines and by-laws governing public transport and “informal” trade in South Africa will be conducted. Finally, through research, formulate a background or a theoretical discourse against which Henri Lefebvre's (1974) theory of 'Production of space' will be discussed, as a way of supporting the premises put forward in this treatise. The architecture that emerges from the research and design process is to be cognizant of local culture, heritage, identity and place through an awareness of the need for sustainable design and building techniques to produce appropriate architectural responses.
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  • Date Issued: 2014

The design of formula one pit complex for Cape Town

  • Authors: Erlangsen, Ashly A
  • Date: 2014
  • Subjects: Racetracks (Automobile racing) -- South Africa -- Cape Town Sports facilities -- South Africa -- Cape Town
  • Language: English
  • Type: Thesis , Masters , MArch
  • Identifier: http://hdl.handle.net/10948/39032 , vital:35022
  • Description: The last time a Formula One Grand Prix took place in South Africa was in 1993. In recent years, there has been a real interest in bringing the event to Cape Town and several proposals have been put forward to the City of Cape Town. Unfortunately, they have all been unsuccessful for various reasons, but mainly, because of the large financial costs involved. The cost involved to build all the infrastructure required for the event is usually reserved for developed, wealthy countries. Despite the positive role that a major event like this can have on the image of a city, there is resistance to invest money into a stadium or sporting infrastructure, which has the sole purpose of serving one big event like a Grand Prix. This treatise therefore focuses on the design of a multi-functional pit complex for a Formula One Grand Prix Street Circuit in Green Point, Cape Town. As an architectural example, which explores the potential of an adaptable approach to creating a long-term, economically sustainable piece of event infrastructure. The design includes all the necessary requirements for a facility of this nature including, a media centre, pit garages, race control centre and hospitality lounges, but adaptable, so as to function within the context of the Green Point area between annual Grand Prix events. The aim is to investigate the issues relating to Formula One Grand Prix as an event and the impact it has on a city. It will further endeavour to conduct a comprehensive study of the context of Green Point so as to gain an understanding of suitable, viable activities that will form part of the pit complex when the race is not in progress. Research into the creation of a structure formed by interchangeable building components and demountable connections are undertaken so as to promote the possibility for future transformation. As a result of this multi-functional, adaptable approach, the building is used all year round. This effectively reduces maintenance costs associated with infrequently-used buildings and allows for the sustainable use of the infrastructure, as a public asset, when the race is not in progress.
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  • Date Issued: 2014

The redevelopment of the railway station Noupoort, Northern Cape

  • Authors: Moore, Maré
  • Date: 2014
  • Subjects: Railroad stations -- South Africa -- Northern Cape -- Designs and plans Railroad stations -- South Africa -- Northern Cape
  • Language: English
  • Type: Thesis , Masters , MArch
  • Identifier: http://hdl.handle.net/10948/38907 , vital:35012
  • Description: This treatise is a redevelopment of the role of the railway station on in the Noupoort because of the reduced industry and resulting economic influence it had on the town. The project developed from an interest in the rural community and it aims to revitalise and integrate the town. Using observations made from site visits and available literature an investigation on was conducted to understand the context and the community. It was found that there is a need for community functions and economic growth. Through urban integration in the centre of the town, community facilities along with skills training can be developed in order to facilitate trade with tourist through the railway connection. As a result a community and tourist facility are designed this connects to the railway and forms an urban link within the town.
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  • Date Issued: 2014

Thinking academic freedom

  • Authors: Lange, Lis
  • Date: 2014
  • Subjects: Academic Freedom -- South Africa Universities and colleges -- South Africa Equality Liberty Education and state -- South Africa Education, Higher -- South Africa
  • Language: English
  • Type: text
  • Identifier: http://hdl.handle.net/10962/784 , vital:19990
  • Description: I have titled this lecture Thinking Academic Freedom, because I would like to make thinking in the Arendtian sense the axis along which to organise this exposition. It was interesting for me that when I sent the title of the lecture I was asked whether I meant thinking or rethinking. It is true that we tend to rethink, revisit and review in the titles of our lectures and papers. This usually means that the accent is not so much on the act of thinking but on the object we are trying to examine. For this occasion, I would like to make the act of thinking itself as important an aspect of the lecture as the issue of academic freedom itself. What interests me is to explore the nature of our work as academics and how this relates to the notion of academic freedom. So, this is my proposed itinerary: I will first stop to flag some of the issues we all know about, current debates on academic freedom which inevitably constitute one layer of the background for these reflections; then I would like to explore with the lens of Hannah Arendt's political thinking the meaning of freedom and thinking in relation to the life of academics. I will then complicate matters further by jumping from Arendt to Pierre Bourdieu's Homo Academicus, after which I hope to land in the not too comfortable terrain of a call to action.
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  • Date Issued: 2014

Thinking Africa Newsletter: (June 2014)

  • Authors: Matthews, Sally
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: vital:38065 , http://hdl.handle.net/20.500.12137/23
  • Description: Thinking Africa Newsletter (June 2014).
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  • Date Issued: 2014

Thinking Africa Newsletter: (March 2014)

  • Authors: Matthews, Sally
  • Date: 2014
  • Language: English
  • Type: text , article
  • Identifier: vital:38067 , http://hdl.handle.net/20.500.12137/22
  • Description: Thinking Africa Newsletter (March 2014).
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  • Date Issued: 2014

Time-activity budgets of cape gannets (Morus Capensis) at Bird Island, Algoa Bay

  • Authors: Rishworth, Gavin Midgley
  • Date: 2014
  • Subjects: Birds of prey -- Behavior -- South Africa -- Algoa Bay , Gannets -- South Africa -- Algoa Bay , Birds -- Breeding -- South Africa -- Algoa Bay
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10728 , http://hdl.handle.net/10948/d1021046
  • Description: For several decades now, seabirds have been considered to be useful indicators of the state of their prey resources because of how they reflect lower-level trophic variability through proxies such as diet or behaviour. However, collection of appropriate data is often challenging in the marine environment because of logistical or financial constraints. In this study, time-activity budgets were studied in the Cape gannet (Morus capensis), a seabird which has been advocated as a potential bioindicator for local epipelagic prey. VHF transmitters attached to PVC leg-rings were fitted to 50 adult breeding pairs during the 2011/2012 and 2012/2013 breeding seasons at Bird Island, Algoa Bay, to determine whether an automated method of continuously collecting time-activity budget data can replace conventional laborious direct observations. To validate that the foraging trip duration data generated from the automated method was a reflection of foraging effort, Time-Depth Recorders (TDRs) were simultaneously equipped to birds with VHF transmitters for three weeks. In order to assess the influence of factors other than prey availability on parent time-activity budgets, sex, chick age and body condition were measured. Additionally, chick growth and survival were recorded in order to investigate the gender-specific effects of parental time-activity budget variability on these parameters. Attachment of VHF transmitters to leg-rings of adult Cape gannets had no observable negative effects on the adults or their chicks in terms of adult body condition, nest attendance and foraging trip durations, or chick growth and survival. Furthermore, the frequency distribution of behaviour bout (foraging trip and nest attendance) durations was no different between automated and directly observed data. However, the automated method did record shorter behaviour bouts, largely attributed to the increased likelihood of direct observations missing birds returning briefly to their nests during older chick provisioning. Additionally, foraging trip duration was highly correlated to foraging effort in terms of time spent resting on the sea surface, flying and diving. The automated method therefore appears to be a good reflection of direct nest attendance observations and foraging effort. Cape gannet time-activity budgets were related to chick age and parental sex. Especially as chicks neared fledging, females spent significantly longer periods of time foraging than males, with males consequently provisioning their chicks more often. Furthermore, adults departing their nests earlier spent more time away from the nest foraging as more same-day daylight hours were available. Chick growth was a function of parent foraging trip duration and associated prey delivery rates. Chick survival was most strongly affected by the amount of time which chicks were left unattended by both parents and consequently exposed to predation by kelp gulls (Larus dominicanus) or to adverse weather conditions. Additionally, for females (but not males) there appeared to be a trade-off between foraging trip duration and chick survival. The Cape gannet appears to demonstrate a strategy whereby the costs of reproduction to the female are shifted towards male-dominated chick provisioning as the chick nears fledging. Drivers of time-activity budget variability such as chick age and parental sex therefore need to be considered if using data on foraging trip duration as a proxy of foraging effort and prey availability.
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  • Date Issued: 2014

Tourism and development : a case study of Mdumbi Backpackers and Transcape non-profit organisation

  • Authors: Hitchcock, Kelly Alexandra
  • Date: 2014
  • Subjects: Mdumbi Backpackers -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape -- Planning , Backpacking -- South Africa -- Eastern Cape -- Case studies , Black people -- Employment -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3377 , http://hdl.handle.net/10962/d1013143
  • Description: The former Transkei region of the Eastern Cape of South Africa, in common with many of the other former Bantustans, is currently facing a developmental backlog. It is one of the poorest regions of the country and is a direct product of South Africa’s history of colonisation and geopolitical nature of apartheid in which people were forcibly located onto former tribal lands, called Bantustans. Tourism is one of the few business opportunities providing employment along the former Transkei coast. The tourism industry has been identified by many worldwide as a key strategy that can lead to economic upliftment, community development and poverty relief in the developing world. The predicament however, lies in the challenge of accepting or managing the negative consequences of tourism for the potential long term benefits offered by tourism-led development. Tourism development theory reflects development theory from traditional, top-down economic-growth based models to a more wide based approach with an emphasis on bottom-up planning, meeting of basic human need and a focus on sustainable development. Consequentially new and alternative forms of tourism have emerged and can be viewed as a response to some of the negative consequences of the mass tourism-led model of economic development. Backpacker tourism is one niche of the tourism market that is providing positive local socioeconomic benefits. This thesis is presented as a case study of Mdumbi Backpackers on the former Transkei coast. Mdumbi Backpackers is a unique example of a model of tourism that is providing meaningful benefits to the people who live in this community. By going one step further with the creation of the non-profit organisation Transcape, their involvement in the community has grown significantly, encouraging positive and sustainable development in the areas of social development, education and health. Mdumbi Backpackers goes beyond the notions of locally owned and sustainable approaches and actively encourages development by setting up community organisations and initiatives in a sustainable and equitable way. This approach to tourism-led development is well suited for the needs and objectives of the community as well preserving the natural environment. This thesis presents an exemplary example from which lessons can be learned and applied to developing tourism in a sustainable and equitable way in other rural communities.
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  • Date Issued: 2014

Tourism management in selected municipalities in the Eden District: a theoretical study

  • Authors: Lamont, Andrew John
  • Date: 2014
  • Subjects: Sustainable tourism -- South Africa , Tourism -- South Africa -- Management
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10948/8025 , vital:24460
  • Description: For attainment sustainable tourism requires the growth of tourism‟s contribution to the economy and society as well as the sustainable use of resources and the environment. The achievement of both relies on dependable and sound understanding, appropriate development and management of the tourism demand. As demand patterns and economic structures change, no industry, and in particular no industry at the national or regional level, could or should assume that there is a constant or increasing flow of demand for its outputs and thus focus solely on resource issues (Butler, 1996). According to Elliot (1997:19) local government plays an important role in tourism, as it is only governments that have the authority to provide political stability, security and the legal and financial framework which tourism requires. Connell et al (2009) argue that one of the more important roles of local government is the development and implementation of community planning, legislation and policy. However, while tourism-related developments are usually integrated with economic development or official community plans, often there is no guiding policy framework or identified area of responsibility for tourism, which can be problematic for effective and sustainable tourism development. The effectiveness of local tourism governance in achieving the goals of sustainable tourism depends on the effectiveness of institutional structures and processes, and the rational resources and skill sets available (Healy, 2006). This study examines the arrangements of selected municipalities and the effectiveness of their local tourism governance and its relevance to sustainable tourism.
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  • Date Issued: 2014

Tourism students' perceptions of their experiential learning experiences based on the place four-component model

  • Authors: Jonas, Lynn Cindy
  • Date: 2014
  • Subjects: Experiential learning , College placement services , Education, Cooperative
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:9581 , http://hdl.handle.net/10948/d1020621
  • Description: The purpose of this study was to determine tourism students’ perceptions of their Experiential Learning (EL) experiences based on the Predicting Learner Advancement through Cooperative Education (PLACE) four-component model. The research objectives were to ascertain Experiential Learning’s impact on the four components namely Personal Development, Career Development, Work-skills Development and Academic Development. This study fits within the pragmatic paradigm and utilised an explanatory mixed methods research design which requires quantitative data to be collected first with follow-up qualitative data. The data collection instrument for the quantitative data was the PLACE model, which was in the form of a survey questionnaire and the data generating strategy for the qualitative data was individual interviews. The findings of the data were heavily skewed toward the positive end of the spectrum with students viewing the impact of EL on the four components as favourable. Interviews were conducted with participants whose results showed deviations from the norm and had particularly negative experiences. Academic Development had extremely low Cronbach Alphas, which points to poor reliability. This phenomenon was also further explored during the interviews with participants making suggestions for factors to be considered. Recommendations were made to the three stakeholders of EL namely students, employers and academic coordinators in order to ensure improved Experiential Learning programmes and maximised student benefit.
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  • Date Issued: 2014

Toward a culture of engagement: leveraging the enterprise social network

  • Authors: Alistoun, Garth
  • Date: 2014
  • Subjects: Communication in organizations -- South Africa Business communication -- South Africa Social media -- South Africa -- Case studies Leadership -- South Africa -- Case studies Human capital -- Management Personnel management Organizational effectiveness
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:1154 , http://hdl.handle.net/10962/d1010869
  • Description: This research aims to provide a theory of enterprise social networking that generates and/or sustains a culture of employee engagement within a chosen South African private sector company. Based on an extensive review of interesting literature and the application of a grounded theory process in a chosen case, this research work provides a theory of enterprise social networking sustaining and growing employee engagement together with an explanatory theoretical framework that makes the theory more practical. Employee engagement is defined as “the harnessing of organisation member’s selves to their work roles; in engagement people employ and express themselves physically, cognitively, and emotionally during role performances.” This research regards employee engagement as a three part concept composed of a trait (personality/cognitive) aspect, a state (emotional) aspect, and a behavioural aspect. Research has shown that employee engagement has an unequivocal positive impact on business outcomes, such as profitability, business performance, employee retention and productivity. Employee engagement can be regarded as a culture if it is abundant within the organization’s employee population. Gatenby et al. (2009) propose that employee engagement is fostered by creating the desire and opportunity for employees to connect with colleagues, managers and the wider organisation. This standpoint is supported by Kular et al. (2008) who state that the “key drivers of employee engagement identified include communication, opportunities for employees to feed their views upward and thinking that their managers are committed to the organisation.” Further indicators of employee engagement include strong leadership (particularly in the form of servant leadership), accountability, a positive and open organisational culture, autonomy, and opportunities for development. One of the key facets of employee engagement is connection. A complementary definition of social media, an umbrella under which enterprise social networks fall, is that “(it) is more of a relationship channel, a connection channel. Each and every tweet, update, video, post, is a connection point to another human being. And it’s the other human being who will determine your worth to them.” Social media provides participants with access to a larger pool of resources and relationships than they would normally have access to. This enlarged relationship/resource pool is a result of expanding human and social capital enabled through social media tools. In order to produce a theory of enterprise social networking sustaining and growing a culture of employee engagement a rigorous grounded theory methodology coupled with a case study methodology was applied. The case study methodology was used to identify a suitable research site and interesting participants within the site while the grounded theory process was used to produce both qualitative and quantitative data sets in a suitability rigorous fashion. The corroborative data was then used to discover and define the emergent theory.
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  • Date Issued: 2014

Towards a framework for enhancing user trust in cloud computing

  • Authors: Nyoni, Tamsanqa B
  • Date: 2014
  • Subjects: Adoption -- Cloud Computing , User Trust
  • Language: English
  • Type: Thesis , Masters , MCom (Information Systems)
  • Identifier: vital:11142 , http://hdl.handle.net/10353/d1014674 , Adoption -- Cloud Computing , User Trust
  • Description: Cloud computing is one of the latest appealing technological trends to emerge in the Information Technology (IT) industry. However, despite the surge in activity and interest, there are significant and persistent concerns about cloud computing, particularly with regard to trusting the platform in terms of confidentiality, integrity and availability of user data stored through these applications. These factors are significant in determining trust in cloud computing and thus provide the foundation for this study. The significant role that trust plays in the use of cloud computing was considered in relation to various trust models, theories and frameworks. Cloud computing is still considered to be a new technology in the business world, therefore minimal work and academic research has been done on enhancing trust in cloud computing. Academic research which focuses on the adoption of cloud computing and, in particular, the building of user trust has been minimal. The available trust models, frameworks and cloud computing adoption strategies that exist mainly focus on cost reduction and the various benefits that are associated with migrating to a cloud computing platform. Available work on cloud computing does not provide clear guidelines for establishing user trust in a cloud computing application. The issue of establishing a reliable trust context for data and security within cloud computing is, up to this point, not well defined. This study investigates the impact that a lack of user trust has on the use of cloud computing. Strategies for enhancing user trust in cloud computing are required to overcome the data security concerns. This study focused on establishing methods to enhance user trust in cloud computing applications through the theoretical contributions of the Proposed Trust Model by Mayer, Davis, and Schoorman (1995) and the Confidentiality, Integrity, Availability (CIA) Triad by Steichen (2010). A questionnaire was used as a means of gathering data on trust-related perceptions of the use of cloud computing. The findings of this questionnaire administered to users and potential users of cloud computing applications are reported in this study. The questionnaire primarily investigates key concerns which result in self-moderation of cloud computing use and factors which would improve trust in cloud computing. Additionally, results relating to user awareness of potential confidentiality, integrity and availability risks are described. An initial cloud computing adoption model was proposed based on a content analysis of existing cloud computing literature. This initial model, empirically tested through the questionnaire, was an important foundation for the establishment of the Critical Success Factors (CSFs) and therefore the framework to enhance user trust in cloud computing applications. The framework proposed by this study aims to assist new cloud computing users to determine the appropriateness of a cloud computing service, thereby enhancing their trust in cloud computing applications.
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  • Date Issued: 2014

Towards sustainable municipalities : an evaluation of sustainability integration in Elundini Local Municipality strategy

Towards the development of a larval feeding strategy for the white-margined sole (Dagetichthys marginatus)

  • Authors: Thompson, Ernst Frederick
  • Date: 2014
  • Subjects: Flatfishes -- South Africa , Soleidae -- South Africa , Soleidae -- Larvae , Soleidae -- Larvae -- Feeding and feeds , Soleidae -- Larvae -- Physiology , Artemia
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5364 , http://hdl.handle.net/10962/d1012982
  • Description: The major bottleneck during the domestication of the white-margined sole Dagetichthys marginatus in South Africa has been low larval survival. The cause of this is not clear but considering current literature on flatfish culture and more specifically soleid culture, nutritional deficiencies are hypothesized to be the main possible cause. Following the importance of nutrition, the first aim of the research was to use an ontogenetic developmental approach to develop a species specific larval feeding strategy. Ontogenetic development of D. marginatus showed that weaning will take place at much later ages than other soleids currently being farmed. This makes the partial replacement of Artemia with a suitable inert diet in co-feeding strategies very important to cut the cost associated of live food production. This leads on to the second aim, in which an 'in vitro' approach was used to model the digestibility of Artemia, which could ultimately contribute towards designing inert feeds with similar digestibility characteristics to Artemia in the future. Obtaining nutrients from food is closely linked to the functional status of the digestive tract, the support organs and the external morphological characteristics required for the ingestion of live or inert feeds. Considering both morphological and physiological ontogenetic development, it is clear that D. marginatus follow a similar pattern to other soleids. Larvae can successfully feed on Artemia as early as 3 days after hatching but exhibit a slow metamorphosis into the juvenile stage when compared to other soleids. The absence of any detectable acidic protease activity during the first 45 days of development and the importance of exogenous enzymes from Artemia all points to limited capacity to digest artificial diets. Prior to modelling the 'in vitro' digestion of Artemia, digestive enzyme activity at different pH's were modelled using functional forms from the normal distributive category of functions. , As there is no substantiated information for the general effects of pH on enzyme activity in the literature for finfish larvae, three species occurring in the same bio-geographical region of Dagetichthys marginatus, namely Sarpa salpa, Diplodus sargus capensis and Argyrosomus japonicus were used to investigate this effect. The fitted parameters, namely the optimal pH and sigma (the slope around the optimal pH) showed two interesting results. When using a negative log likelihood ratio test to test for differences between species for a particular enzyme, the optimal pH for alkaline proteases (7.67), lipase (8.03), amylase (7.69) and phosphatase (9.84) activity was the same for all three species. Furthermore, the study illustrated the potential to detect dietary shifts during ontogenetic development based on changes in enzyme activity around the optimal pH using the sigma parameter. Sarpa salpa showed increased amylase activity and a decrease in protease activity around the optimal pH with increased size, corresponding to a change in diet from zooplankton to algae. The 'in vitro' modelling approach taken in this study was based on known enzyme interactions and dynamics which makes the results very interpretable. from Artemia is achieved based on gut evacuation time and enzyme levels. This 'in vitro' study furthermore clearly indicates the importance of exogenous enzymes from Artemia, contributing as much as 54 percent to protein digestion and 64 – 72 percent to carbohydrate digestion. This was however, only an initial investigation, and further expansion of the model is required to achieve a complete understanding of Artemia digestion and ultimately partial replacement with artificial diets. A feeding strategy for D. marginatus should therefore follow those of other farmed soleids, although there will be a general delay in implementation due to slower development. Problems can thus be solved and improvements made by transferring technology from other soleids to D. marginatus.
  • Full Text:
  • Date Issued: 2014

Towards the feasibility of a landowner enterprise in the western Baviaanskloof : an external stakeholder analysis

  • Authors: Wiles, Kira Leigh Deborah
  • Date: 2014
  • Subjects: Landowners -- South Africa -- Eastern Cape , Natural resources -- Co-management -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Land use -- Economic aspects -- South Africa -- Eastern Cape , Partnership -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:1198 , http://hdl.handle.net/10962/d1012075 , Landowners -- South Africa -- Eastern Cape , Natural resources -- Co-management -- South Africa -- Eastern Cape , Land use -- Environmental aspects -- South Africa -- Eastern Cape , Land use -- Economic aspects -- South Africa -- Eastern Cape , Partnership -- South Africa -- Eastern Cape
  • Description: In May 2012, a meeting was held between various stakeholder representatives of the Western Baviaanskloof to discuss the concept of a proposed landowner-enterprise. This concept was put forward in response to a need for collaboration in the midst of economic, environmental and social issues at play in the Baviaanskloof. Owing to the conservation value and rapidly decreasing economic output of the land, a radical shift to sustainable land-use practices was called for by various stakeholders. Suggested as a vehicle to generate income for the local landowners through alternative sustainable land-uses, the proposed enterprise may aid in addressing this shift by use of a bottom-up approach. During the stakeholder meeting, it was requested by the representative landowners that a feasibility assessment be conducted on the concept of the proposed enterprise prior to establishment. As an integral part of this assessment, the researcher took on the task of investigating stakeholder reception to the enterprise by means of a stakeholder analysis. It was decided to limit this to three markets: water, carbon and tourism. The purpose of this research study is twofold, namely to: investigate stakeholder influence and their reception of the proposed enterprise using a stakeholder analysis; and also to identify and advise on the opportunities and constraints relating to stakeholders, thus contributing to determining the feasibility of the proposed enterprise. In achieving the purpose of this study, a systematic stakeholder analysis framework was constructed, based on existing theory. This was necessary because, although stakeholder analysis is commonly practiced, no study was found to provide a theoretically based framework for the purpose of feasibility in the initial stages of enterprise establishment. Thus the contribution of the study is also twofold, namely the practical outcome of determining stakeholder reception for feasibility, and a secondary outcome of constructing a stakeholder analysis framework. The stakeholder analysis framework is based on an interpretation of existing stakeholder theory, with the addition of four "relational indicators" – goals, intentions, relationships, and resources. These four indicators provide a link between theory and practice in gauging the two attributes of stakeholder influence – power and interest. Dealing with a number of stakeholder interests in a unique context, the study takes on a single network case study approach in the paradigm of phenomenology. To suit the complex nature of the study, semi-structured interviews with various stakeholder representatives were conducted, using groups or organisations as units of analysis. Drawing from the stakeholder analysis framework and overall purpose of the study, four research objectives were set. The first was to identify the proposed enterprise's legitimate key external stakeholders, based on the three markets: water, carbon and tourism; the second to describe, categorise and assess relative dyadic influence of the above stakeholders by gauging their power and interest; the third, to determine the stakeholder network influence and probable reception of the proposed enterprise; and the last to advise the landowners on any identified opportunities or constraints stakeholders might pose, and thus to contribute to determining feasibility. In addressing the first objective, 21 stakeholders were identified, 12 of whom were found to be key to the current investigation. These key stakeholders were: Gamtoos Irrigation Board (GIB), LivingLands, R3G, Rhodes Restoration Group, Eastern Cape Parks and Tourism Agency (ECPTA), Department of Water Affairs (DWA), Nelson Mandela Bay Metropolitan (NMBM), Saaimanshoek, South African National Biodiversity Institute (SANBI), Department of Economic Development, Environmental Affairs and Tourism (DEDEAT), Baviaans Tourism, and Baviaans Municipality. In applying the stakeholder analysis framework, ECPTA was categorised as the definitive (most influential) stakeholder to the enterprise, and DEDEAT, SANBI (through Working for Wetlands), Baviaans Tourism, GIB, and NMBM were categorised as pivotal (influential and active). In discerning stakeholder interest in the proposed enterprise, a number of emerging themes were found to affect the projected interest and behaviour of stakeholders, apart from their specified goals. Emerging themes included: tunnel visioning, internal disparity, individual/personality clashes, and misaligned interests. In addition to this, in interpreting stakeholder interest, specific intentions or agendas that might affect the interest shown towards the proposed enterprise were also taken into account. Five predominant intentions of stakeholders were identified as: implementing a stewardship programme, establishing a tourism association, establishing a water users' association, social development, and "the big vision". Findings on the final objective revealed a number of perceived opportunities and constraints relative to the feasibility of the enterprise. Three prime opportunities were identified as: partnerships with definitive and pivotal stakeholders, the possibility of tendering for implementer of the "Working for" programmes, and taking on the role of Tourism Association. The following potential constraints were also emphasised by participants: social aspects such as individuals and personalities, the incompatibility or non-existence of local market structures, and the need for external funding. With regard to stakeholder reception, most of the stakeholders, with the exception of NMBM and Saaimanshoek, responded positively to the idea of the enterprise. Overall, based on participant perceptions, the tourism market was found to be the most feasible the carbon market uncertain and a long-term possibility, and the water market the least feasible.
  • Full Text:
  • Date Issued: 2014

Towards the modeling of indigenous poultry production in the Eastern Cape Province, South Africa: characterization and extension evaluation for poverty reduction

  • Authors: Yusuf, Shehu Folaranmi Gbolahan Shehu
  • Date: 2014
  • Subjects: Poultry -- Breeding -- South Africa -- Eastern Cape , Chickens -- Breeding -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Doctoral , PhD (Agricultural Economics)
  • Identifier: vital:11223 , http://hdl.handle.net/10353/d1019833 , Poultry -- Breeding -- South Africa -- Eastern Cape , Chickens -- Breeding -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
  • Description: Poverty remains a critical issue mostly in the rural South Africa. Various initiatives, policies and programs have been enacted by the government with attempting to reduce poverty at the national and provincial levels; poverty is yet to be abated. The target of the Millennium Development Goal 1 (MDG1) of halving poverty by the year 2015 notwithstanding, poverty remains a threat to quality livelihoods. Agriculture has continued to be one of the pillars of government efforts to address poverty. However, in livestock production interventions, efforts of government had largely been on cattle, sheep, goats, pigs and exotic poultry with little attention being given to indigenous poultry production (IPP). This study explores the option of using IPP to address rural poverty by capitalizing on its minimal inputs while recognizing its prevalence in a variety of households. The study addresses the characterization of the IPP from the perspectives of housing, feeding, healthcare management, breeding and marketing options.Skill competencies of the indigenous poultry farmers (IPFs) and the Agricultural Development Technicians (ADTs) were examined. This study reviewed poultry models in different parts of the world with special attention to Africa. The human resource development program of the department of rural development and agrarian reform was discussed. The study employed the use of multi-methods approach, the quantitative and qualitative research methodologies. Descriptive statistical analysis, frequent count, percentage, means, standard deviation, chisquare, and principal component analysis was used in the quantitative data analysis while the “open social system” was used for the qualitative methodology. Findings revealed that IPFs face some challenges among which are, the poor housing that exposed the birds to inclement weather, predator attacks and stock theft, high mortality of chicks after hatching and expensive feed for the flock. The IPFs showed competencies in nine skill items that included ability to identify chicken predators (x=3.92) and high yielding chickens (x=3.79); control of predators(x=3.77); methods of using ethno veterinary drugs to treat chicken diseases and pests (x=3.72), and identify signs of diseases (x=3.69), among others. However, the ADTs did not show any competency in any of the 32 skills items. The principal component analysis with Varimax rotation was performed to ascertain the dimensionality of the measures. Six factors with eigen value of >1, which accounted for 77.317% were extracted, with each factor loading ranging from 0.523 to 0.93. Factor loading after rotation that emerged on the same component was described; as brooding, shelter and care of the chicks; predators and healthcare; hygiene and litter management; feeds and feeding stuff; and record keeping and marketing. The findings on the human resource development revealed that staff meetings were the most common method of capacity development. This was followed by in-service-training, formal study, workshop, and on the job training. The farmers’ field school and study tours were sparingly used. However, respondents were in favor of on-site training, staff meetings, formal study and in-service training. The findings on the appropriate model suggest a theoretical indigenous poultry production model (IPPM) for the Eastern Cape Province (ECP). The “open social system” was used to develop a framework for an indigenous poultry cooperative society (to be known as Abafuyi Benkukhu Zemveli [ABZ]). This was meant to create a binding force for capacity development, a strong economic foundation through equity contributions, creation of marketing channels, and the development of a concept of ‘‘our own'' product in the market. Lastly, the study offers options for a training program that would accommodate the new initiatives, with a strong capacity development training approach. In this context, the study advocates for institutional support for the IPFs and the incorporation of indigenous poultry in the curriculum of the agricultural training programs at higher education institutions in South Africa.
  • Full Text:
  • Date Issued: 2014

Towards understanding the effects of stocking density on farmed South African abalone, Haliotis Midae

  • Authors: Nicholson, Gareth Hurst
  • Date: 2014
  • Subjects: Haliotis midae -- South Africa , Haliotis midae fisheries -- South Africa , Abalones -- South Africa , Fish stocking -- South Africa , Abalone populations -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5371 , http://hdl.handle.net/10962/d1015646
  • Description: The profitability of abalone farms is heavily influenced by their production per unit of grow-out space. With farms having physically expanded to the maximum, and with increasing production costs, one of the most realistic ways for farms to increase their production is through optimizing stocking densities. The effect of stocking density on Haliotis midae performance is undocumented and optimal stocking densities for this species have not been determined. Experiments were conducted under farm conditions to investigate the effects of four different stocking densities (16 %, 20 %, 22 % and 24 % of available surface area) on growth, production and health of three different size classes of abalone (15-35 g, 45-65 g, and 70-90 g start weight). Each treatment was replicated four times and trials ran over a period of eight months with measurements being made at four month intervals. Abalone behaviour was observed during the trials in the experimental tanks. Weight gain per abalone decreased with an increase in density for all tested size classes (5.04 ± 0.18 to 2.38 ± 0.17; 5.35 ± 0.21 to 4.62 ± 0.29; 7.97 ± 0.37 to 6.53 ± 0.28 g.abalone-1.month-1 for the 15-35, 45-65 and 70-90 g classes respectively, with an increased density of 16 to 24 %). Individual weight gain of 15-35 g abalone was similar at stocking densities of 16 % and 20 % while weight gain of 45-65 g and 70-90 g abalone decreased when density was increased above 16 %. Biomass gain (kg.basket-1.month-1) was not affected by stocking density in the 15-35 g and 45-65 g size classes (1.29 ± 0.02 and 0.97 ± 0.02 kg.basket-1.month-1 respectively). However, the biomass gained by baskets stocked with 70-90 g abalone increased with stocking density (1.08 ± 0.02 to 1.33 ± 0.02 kg.basket-1.month-1) with an increased density of 16 to 24 %) and did not appear to plateau within the tested density range (16 to 24 %). Food conversion ratio did not differ significantly between densities across all size classes. Stocking density did not have a significant effect on abalone condition factor or health indices. The proportion of abalone above the level of the feeder plate increased with density (7.26 ± 1.33 to 16.44 ± 1.33 with an increased density of 16 to 24 %). As a proportion of abalone situated in the area of the basket, the same proportions were situated on the walls above the feeder plate and on the feeder plate itself irrespective of stocking density (p > 0.05). Higher proportions of animals had restricted access to feed at higher stocking densities (p = 0.03). The amount of formulated feed available on the feeder plate did not differ between stocking densities throughout the night (p = 0.19). Individual abalone spent more time above the feeder plate at higher stocking densities (p < 0.05). The percentage of time above the feeder plate, spent on the walls of the basket and on the feeding surface was not significantly different at densities of 20 %, 22 % and 24 % (p > 0.05) but abalone stocked at 16 % spent a greater percentage of time above the feeder plate on the feeding surface (83.99 ± 6.26 %) than on the basket walls (16.01 ± 6.26 %). Stocking density did not affect the positioning of abalone within a basket during the day or at night. Different size H. midae are affected differently by increases in stocking density in terms of growth performance. Findings from this research may be implemented into farm management strategies to best suit production goals, whether in terms of biomass production or individual weight gain. The fundamental mechanisms resulting in reduced growth at higher densities are not well understood, however results from behaviour observations suggest that competition for preferred attachment space and feed availability are contributing to decreased growth rates. With knowledge of abalone behaviour at different densities, innovative tank designs may be established in order to counter the reduction in growth at higher densities.
  • Full Text:
  • Date Issued: 2014
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