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The Ecca type section (Permian, South Africa) : an outcrop analogue study of conventional and unconventional hydrocarbon reservoirs

  • Authors: Campbell, Stuart Alexander
  • Date: 2015
  • Subjects: Hydrocarbon reservoirs -- Ecca Group , Geology, Stratigraphic -- Permian , Paleogeography -- Ecca Group , Shale gas -- Ecca Group , Shale gas reservoirs -- Ecca Group , Ecca Group , Ripon Formation (South Africa) , Collingham Formation (South Africa)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5083 , http://hdl.handle.net/10962/d1018199
  • Description: The Karoo Basin of South Africa holds an estimated 906 billion to 11 trillion cubic meters of unconventional shale gas within the shales of the Whitehill and Collingham formations of the Ecca Group. Evaluation of this potential resource has been limited due to the lack of exploration and a scarcity of existing drill core data. In order to circumnavigate this problem this study was undertaken to evaluate the potential target horizons exposed in outcrops along the southern portion of the Karoo Basin, north of Grahamstown in the Eastern Cape Province. Detailed field logging was done on the exposed Whitehill and Collingham formations as well as a possible conventional sandstone (turbidite) reservoir, the Ripon Formation, along road cuttings of the Ecca Pass. Palaeocurrent data, jointing directions and fossil material were also documented. Samples were analysed for mineralogy, porosity, permeability, and total organic carbon content (TOC). The extensively weathered black shales of the Whitehill Formation contain a maximum TOC value of 0.9% and the Collingham Formation shales contain a maximum TOC value of 0.6%. The organic lithic arkose sandstones of the Ripon Formation are classified as ‘tight rock’ with an average porosity of 1% and an average permeability of 0.05 mD. The Whitehill Formation in the southern portion of the Karoo Basin has experienced organic matter loss due to low grade metamorphism as well as burial to extreme depths, thus reducing shale gas potential. The Ripon Formation is an unsuitable conventional reservoir along the southern basin boundary due to extensive cementation and filling of pore spaces.
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  • Date Issued: 2015

Design of a low-cost autonomous guided cart for material handling

  • Authors: Cawood, Gareth James
  • Date: 2015
  • Subjects: Automobiles -- Design and construction , Automobiles -- Automatic control , Vehicles -- Automatic control
  • Language: English
  • Type: Thesis , Masters , MEngineering
  • Identifier: vital:9655
  • Description: This dissertation covers the design and manufacture of an autonomous guided cart (AGC) for use in the material handling industry. General Motors South Africa (GMSA) requires a low-cost AGC for use in their Struandale plant. A budget of R35 000 per unit was proposed. The researcher, in collaboration with staff at GM, compiled a list of engineering requirements for the AGC. After research into the unique problems of the project, an examination of a previous design attempt by staff of GM Thailand, the researcher developed a new design, the subject of this report. Different solutions for each design problem were investigated before the design was finalised. A three-wheeled vehicle was designed making use of two motors in a differential-drive setup to control motion. Navigation is via a line-following mechanism, using an induction sensor-array in conjunction with a pre-laid metallic strip. To aid the design, the system was modelled to understand the different control elements at play. The researcher developed software for several aspects of the design: for the PLC controlling the system and motors; for a microcontroller that communicates with the PLC and a wireless module; for a computer server that communicates with a second wireless device, receiving information from the PLC; and a web interface to view this information. These form the SCADA integration of the project. The final product meets the GMSA specifications. It is a robot capable of towing a trolley of mass not exceeding 350 kg. While the robot is able to navigate a pre-laid route, it cannot reliably stop at marked locations. It is possible to monitor the system via a web-interface. The robot is capable of operating for an entire 8-hour shift before the batteries need to be recharged. The total cost of the prototype was R26 340.
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  • Date Issued: 2015

Towards a Mobile Bioethanol Unit for point of source conversion of sugar sources to bioethanol: design and feasibility study for South Africa

  • Authors: Cech, Alexandra Louise
  • Date: 2015
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/59141 , vital:27439
  • Description: Restricted access-thesis embargoed for 5 years
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  • Date Issued: 2015

Production of Cydia pomonella granulovirus (CpGV) in a heteralogous host, Thaumatotibia Leucotreta (Meyrick) (False codling moth)

  • Authors: Chambers, Craig Brian
  • Date: 2015
  • Subjects: Cryptophlebia leucotreta -- South Africa , Codling moth -- South Africa , Apples -- Diseases and pests -- South Africa , Codling moth -- Biological control -- South Africa , Insect pests -- Biological control -- South Africa , Biological pest control agents -- South Africa , Baculoviruses -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: vital:5935 , http://hdl.handle.net/10962/d1017906
  • Description: Cydia pomonella (Linnaeus) (Family: Tortricidae), the codling moth, is considered one of the most significant pests of apples and pears worldwide, causing up to 80% crop loss in orchards if no control measures are applied. Cydia pomonella is oligophagous feeding on a number of alternate hosts including quince, walnuts, apricots, peaches, plums and nectarines. Historically the control of this pest has been achieved with the use of various chemical control strategies which have maintained pest levels below the economic threshold at a relatively low cost to the grower. However, there are serious concerns surrounding the use of chemical insecticides including the development of resistance in insect populations, the banning of various insecticides, regulations for lowering of the maximum residue level and employee and consumer safety. For this reason, alternate measures of control are slowly being adopted by growers such as mating disruption, cultural methods and the use of baculovirus biopesticides as part of integrated pest management programmes. The reluctance of growers to accept baculovirus or other biological control products in the past has been due to questionable product quality and inconsistencies in their field performance. Moreover, the development and application of biological control products is more costly than the use of chemical alternatives. Baculoviruses are arthropod specific viruses that are highly virulent to a number of lepidopteran species. Due to the virulence and host specificity of baculoviruses, Cydia pomonella granulovirus has been extensively and successfully used as part of integrated pest management systems for the control of C. pomonella in Europe and around the world, including South Africa. Commercial formulations have been typically based on the Mexican strain of CpGV. However due to long-term multiple applications of CpGV and the reliance on CpGV in organic farming practices in Europe, resistance to the CpGV-M strain has developed in a number of field populations of C. pomonella. This study aimed to identify and characterize novel isolates of CpGV in South Africa and compare their virulence with the commercial standard CpGV-M. Secondly, since C. pomonella is difficult to culture on a large scale, an alternate method of CpGV production was investigated in order to determine if CpGV could be produced more efficiently and at a reduced cost without negatively impacting the quality of the product. Several isolates of CpGV were recovered either from field collected larvae or from a laboratory-reared C. pomonella colony. Characterisation of DNA profiles using a variety of restriction enzymes revealed that only a single isolate, CpGV-SA, was genetically different from the Mexican strain of the virus used in the commercially available CpGV based products in South Africa. In dose-response bioassays using CpGV-SA, LC₅₀ and LC₉₀ values for neonate C. pomonella larvae were 3.18 x 10³ OBs/ml and 7.33 x 10⁴ respectively. A comparison of these values with those of CpGV-M indicated no significant difference in the virulence of the two isolates under laboratory conditions. This is a first report of a genetically distinct CpGV isolate in South Africa. The biological activity and novelty of CpGV-SA makes this isolate a potentially important tool for CpGV resistance management in South Africa. In order to justify production of CpGV in an alternative host, studies on the comparative biological performance of C. pomonella and T. leucotreta based on oviposition, time to hatch, larval developmental times and rearing efficiency as well as production costs were performed. Thaumatotibia leucotreta was found to be more fecund and to have significantly shorter egg and larval developmental times. In addition, larval production per unit of artificial diet was significantly higher than for C. pomonella. This resulted in T. leucotreta being more cost effective to produce with implications for reduced insectary space, sanitation practices as well as the labour component of production. Virus yield data generated by inoculation both C. pomonella and T. leucotreta with nine concentrations of CpGV resulted in comparable virus yields, justifying the continuation of the research into production of CpGV in T. leucotreta. It was important to determine the LC and LT values required for mass production of CpGV in late instar T. leucotreta larvae. Dose- and time-response bioassays with CpGV-M were conducted on artificial diet to determine these values. Fourth instar LC₅₀ and LC₉₀ values were 5.96 x 10³ OBs/ml and 1.64 x 10⁵ OBs/ml respectively. LT50 and LT90 values were 81.10 hours and 88.58 hours respectively. Fifth instar LC₅₀ and LC₉₀ values were 6.88 x 10⁴ OBs/ml and 9.78 x 10⁶ OBs/ml respectively. LT₅₀ and LT₉₀ values were 111.56 hours and 137.57 hours respectively. Virus produced in fourth instar T. leucotreta larvae was bioassayed against C. pomonella neonate larvae and compared to CpGV-M to establish if production in the heterologous host negatively affected the virulence of the isolate. No significant difference in virulence was observed between virus produced in T. leucotreta and that produced in C. pomonella. The data generated in the bioassays was used in CpGV mass production trials to evaluate production. All production methods tested produced acceptable virus yields. To examine the quality of the virus product, genomic DNA was extracted from larval cadavers and subjected to REN analysis with HindIII. The resulting DNA profiles indicated that the virus product was contaminated with the homologous virus, CrleGV. Based on the above results, the use of T. leucotreta as an alternate host for the in vivo production of CpGV on a commercial basis is not at this stage viable and requires further investigation before this production methodology can be reliable used to produce CpGV. However, this study has shown that CpGV can be produced in a homologous host, T. leucotreta and significant strides have been made towards developing a set of quality control standards that are essential for further development of successful production methodology. Finally a novel isolate of CpGV has been identified with comparable virulence to the CpGV-M. This is an important finding as it has broad reaching implications for resistance management of CpGV products in South Africa.
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  • Date Issued: 2015

Conceptions of academics concerning the nature and purpose of teaching portfolios in higher education

  • Authors: Champion, Eunice Nomava
  • Date: 2015
  • Subjects: Portfolios in education , Lecture method in teaching , College teaching , College teachers
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:9591 , http://hdl.handle.net/10948/d1021175
  • Description: The purpose of this study was to explore the conceptions of academics at the NMMU concerning the nature and purpose of teaching portfolios in higher education. The study was guided by the following research question: What are the conceptions of academics concerning the nature and purpose of teaching portfolios in higher education? A case study, involving academics at the Nelson Mandela Metropolitan University (NMMU), was used to answer the research question. A sequential explanatory mixed-methods research design was employed to collect data from an electronic questionnaire consisting of Likert-scale type of responses and open-ended questions, followed by two focus group interviews with academics that had prior experience in the development of a teaching portfolio. Forty-five academics responded to the questionnaire sent to all the academics at the NMMU, providing a broad perspective on the conceptions of NMMU academics regarding the nature and purpose of teaching portfolios. The two focus group interviews were conducted with six and eight academics respectively who was purposively chosen for their prior experience with the development of teaching portfolios. The aim of the focus group interviews were to elaborate on the data generated by the questionnaire. The quantitative data gathered by the questionnaire was statistically analysed, generating descriptive statistics of the Likert type response statements. The transcripts of the focus group interviews were thematically analysed. The conceptual framework that initially guided the formulation of the sub-research questions was amended to include the themes that emerged from the thematic analysis of the data, namely: the portfolio development process, the uses of and purposes for developing teaching portfolios, the attitudes of academics towards teaching portfolios, and the benefits gained from the development of teaching portfolios. The findings of the study revealed that of the participants find work overload and additional responsibilities as major constraints and collaboration among peers as the most helpful factor in the development of a teaching portfolio. The findings further revealed that the majority of the participants identified items to be included in a teaching portfolio that would enable them to use the portfolio in the development of their teaching. A mixture of attitudes towards teaching portfolios was identified. Some academics (in particular those who have prior experience in the development of portfolios) displayed a positive attitude towards teaching portfolios, while participants reported a negative attitude towards teaching portfolios by most of their colleagues (mostly those who have not developed a portfolio yet). The negative attitudes do seem to overpower the positive attitudes towards teaching portfolios. The challenge to the NMMU would therefore be to get academics to make use of the initiatives provided by the NMMU to assist them with the teaching portfolio development process. Four recommendations that may serve as guidelines to assist in the successful implementation of teaching portfolios at the NMMU were made, based on the findings of the study. Although the results of this study cannot be generalized to other higher education institutions, they do provide insights in the conception of the academics regarding the nature and purpose of teaching portfolios at the NMMU that can be of benefit to other higher education institutions.
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  • Date Issued: 2015

An investigation into how two Grade 11 Physical Science teachers mediate learning of the topic chemical equilibrium : a case study

  • Authors: Chani, Fungisisai M
  • Date: 2015
  • Subjects: Chemical equilibrium -- Study and teaching (Secondary) -- Namibia , Science -- Study and teaching (Secondary) -- Namibia
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2023 , http://hdl.handle.net/10962/d1017334
  • Description: The Namibian Physical Science Higher Level Syllabus requires students to study the topic on chemical equilibrium. This section has proven to be one of the most difficult for Namibian learners as reflected by their poor responses to questions in the Grade 12 NSSC ‘H’ examinations. Triggered by these discoveries, I decided to conduct a research on how teachers mediate learning of the topic on chemical equilibrium in a Namibian context. Conducted at a private school in Windhoek, the study involved two experienced Grade 11 Physical Science teachers renowned for good results. I adopted a qualitative case study underpinned by an interpretive paradigm. Sense making of concepts on chemical equilibrium was my unit of analysis. To generate data, I used document analysis, semi-structured interviews, lesson observations, which were videotaped as well as stimulated recall interviews. Vygotsky’s mediation of learning and social constructivism blended with Shulman’s pedagogical content knowledge (PCK) were the theoretical frameworks adopted in the study. During the analysis process, there was grouping of data into categories. These included teacher-learner interactions as emphasized by Vygotsky’s mediation of learning and learners’ challenges according to PCK. I used an inductive approach to identify emerging themes from my data. The themes were colour coded and the developed into analytical statements. Data triangulation, member checking, and peer review ensured data validity and trustworthiness. Stimulated recall interviews conducted while watching the videos with the two teachers, complemented these approaches. My findings were that teachers extensively used various meditational tools such as prior knowledge, language, analogies and an equilibrium game to mediate learning. The teachers experienced numerous challenges during mediation of learning, including language difficulties and learners’ failure to comprehend complex chemical equilibrium concepts. Notwithstanding, the teachers in this study managed to some extent to overcome the challenges by exhibiting facets of advanced PCK.
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  • Date Issued: 2015

Training of officials in the Buffalo City Metropolitan Municipality

Hydrothermal co-liquefaction of microalgae biomass and coal

  • Authors: Charlie, David
  • Date: 2015
  • Subjects: Microalgae -- Biotechnology Biomass chemicals , Biomass energy
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: http://hdl.handle.net/10948/50087 , vital:42035
  • Description: In this research, the objective was to investigate under the chosen liquefaction conditions whether co-liquefaction of coal and microalgae biomass as agglomerates does possess a distinct advantage over the individual liquefaction of microalgae and coal. This was initially done by preparing dry micro algal biomass, followed by the preparation of coal fines and finally coal-algae as agglomerates. The agglomerates were prepared by continuously adsorbing wet concentrated microalgae slurry/solution onto the dry coal fines in order to prepare different ratios of coal-algae agglomerate(s). Ultimate analysis of the starting material (coal fines and the microalgae) as well the agglomerates then followed. According to research, wet microalgae biomass has the potential of acting as a hydrogen donor. By preparing the agglomerates, the rationale was to promote hydrogen supply from the micro algal biomass that has high hydrogen content to the coal with lower hydrogen content. The resulting product was then expected to have fairly higher hydrogen content. However, this was not observed or evident from the elemental analysis results. The results (elemental composition) showed no difference between the agglomerates and the coal. Based on the observed ultimate analysis results, liquefaction experiments were conducted to determine whether hydrogen transfer and the expected synergistic effect between micro algal biomass and coal would occur. The crude oil product was recovered and simulated distillation technique was used for the characterization of the crude oil product. The results we in agreement that higher yields can be achieved during co-liquefaction as compared to the individual liquefaction. A possible synergistic effect that was investigated in this research existed. Liquefaction results provided evidence of higher yields recovery from the agglomerates compared to those of coal fines and microalgae biomass. Although there was higher recovery on the agglomerates, there appears to be a downward trend (decrease) in product recovery with higher loadings of micro algal biomass on to the coal. This means that higher loading of micro algal biomass tend to suppress liquefaction of coal, thus resulting in lower product recovery. While lower loadings tend to effectively facilitate the liquefaction of coal, thus proving that the proposed synergistic effect between the two does exist. Overall product recovery (yields) of the agglomerates is higher compared to the individual recovery of coal fines and microalgae biomass. This was followed by mass balancing to determine the overall conversion. Higher conversions were achieved on the agglomerates compared to coal. This could mean that microalgae have the potential to facilitate the liquefaction of coal and improve its conversion. The observed trend results in improved conversion as well as higher oil yields (simulated distillation results). Overall, the mass balancing provided insightful information regarding the coal-microalgae interaction based on the conversion, and this further corresponds or supports the simulated distillation results. This research paper provides evidence of the synergistic effect that exists between micro algal biomass and coal.
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  • Date Issued: 2015

Detriments associated with substance abuse among out - of - school youth in Ntselamanzi, village, Alice Town

  • Authors: Chatikobo, Nyasha
  • Date: 2015
  • Subjects: Substance abuse--South Africa--Eastern Cape , Drug abuse--South Africa--Eastern Cape , Youth--Substance use--South Africa--Eastern Cape
  • Language: English
  • Type: Master's theses , text
  • Identifier: http://hdl.handle.net/10353/19442 , vital:43087
  • Description: The main aim of the study was to investigate the detriments associated with substance abuse among the out- of- school youth of Ntselamanzi Village in Alice. This study intended to achieve the following objectives. (i) to establish the causes of increased indulgence in substance abuse in Ntselamanzi village, Eastern Cape. (ii) to identify the various kinds of drugs abused by the society of Ntselamanzi (iii) to identify the consequences of substance abuse to the lives of the out-of-school youth. (iv) to suggest the strategies that can be used to reduce substance abuse in order to enhance the youth‟s socio-economic growth and societal bliss. Using the quantitative method ninety-eight questionnaires were administered to the out-of-school youth in Ntselamanzi village and eighty questionnaires were returned fully answered. The major findings of the study outlined that dominating factors of substance abuse in Ntselamanzi village were family drug use, increased drug accessibility, lack of recreation and peer influence. As a result drug abuse among the out of school youth has indicated that the youth end up dropping out of school, unemployed, facing health complications and committing anti-social activities in the village which causing family conflicts and rifts in the community. These all affected the out-of-school youths‟ well-being, academic future and their quality of life was lowered due to all related issues with drug abuse. It can be concluded that drug use among rural outof-school youth is detrimental to the out-of-school youths, their families destroyed and their community crippled from the anti-social activities that take place. The future of the youths‟ education is hampered; the quality of persons in the community and families is lowered. Having unproductive out-of-school youth as a result of drug abuse is not good for the development of the village and all the persons therein. , Thesis (M Soc Sc) (Social Work) -- University of Fort Hare, 2015
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  • Date Issued: 2015

Sedimentological and geochemical investigations on borehole cores of the Lower Ecca Group black shales, for their gas potential : Karoo basin, South Africa

  • Authors: Chere, Naledi
  • Date: 2015
  • Subjects: Sediments (Geology) -- South Africa , Gas reservoirs -- South Africa , Natural gas reserves -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:10679 , http://hdl.handle.net/10948/d1021201
  • Description: In the recent years, the shale gas discourse has become central to discussions about future energy supply in South Africa. In particular, the Permian black shales of the Lower Ecca Group formations in the Karoo Basin are considered potential source rocks for shale gas. The research presented in this thesis advances the understanding of the shale gas potential of mainly the Prince Albert, Whitehill and Tierberg/Collingham Formations. These shale sequences were sampled from eight deep boreholes spread across the main Karoo Basin and geochemically analysed at the GFZ - Helmholtz Centre Potsdam, Germany. Three key questions guided the study, these are: (i) what is the lithology of the sequence; (ii) where in the basin do the shale sequences attain maximum thickness at optimum depth i.e. beneath 1000-1500m; and (iii) and their shale characteristics. To evaluate these, borehole core logging, petrology and organic geochemistry were used extensively. Petrology involved the use of thin section, scanned electron and transmission electron microscopy for mineralogy as well as the identification of sedimentary features, organic matter and nano-scale porosity. These were coupled with standard organic geochemistry techniques such as Rock Eval. analysis, open pyrolysis gas chromatography and thermovaporisation to quantify the free gas, total organic carbon (TOC), present-day gas generative potential and kerogen type. The results show that the Whitehill Formation, away from the CFB and not intruded by dolerite, has the most potential for shale gas. Microscopic studies of this pyritic black shale reveal the occurrence of porous amorphous matter, indicating thermal maturity within the gas generation zone (i.e. > 1.1 percent Ro, 120ºC). The TOC content is consistently high within the Whitehill (exceeding industry requirement of 2 percent), attaining maximum of 7.3 percent. The highest yields of free and desorbed gas, especially methane, were emitted within this formation (S1 and nC1 peaks); mostly within its dolomitic units. In addition, dissolution porosity within dolomite units of the Whitehill Formation was identified as the predominant type of porosity. Thus, it is deduced that the dolomitic units of Whitehill Formation potentially contain the greatest volumes of free gas. HI values attain maximum of 25 mg HC/g TOC, whereas the OI values 26 mg CO2/g TOC. Such low HI and OI values are typically attributed to the dominance of Type IV kerogen, and consistent with overmaturity. Open pyrolysis (GC) show the main the chemical compound of the organic matter to be m-p-xylene, consistent with a mix of Type III, Type I/II and Type IV kerogen. Lithologically, the Whitehill Formation is composed of ~ 35 quartz, 13 percent feldspar, 26 percent illite and ~ 23 percent dolomite with variable amounts of pyrite. The dominance of quartz is directly proportional to the brittleness of the rock. Thus it can be deduced that the Whitehill Formation is relatively brittle and therefore fraccable. Burial trends indicate increasing depth (from ground level) to the top of the Whitehill Formation towards the south and south-eastern portion of the basin. It is in the southern region where thicknesses of this black shale exceeding 50m occur at depths more than 1500m; 1000m beneath fresh water aquifers. It therefore concluded that Whitehill Formation in the southern portion of Karoo Basin, but away from the thermo-tectonic overprint of the Cape Orogeny, is the most probable shale gas reservoir in South Africa.
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  • Date Issued: 2015

Engaging within zones of proximal development on Facebook : the case of using Facebook to support learning and mentoring on a NQF Level 5 environmental education, training and development practices learnership

  • Authors: Chetty, Preven
  • Date: 2015
  • Subjects: Social media -- Study and teaching (Higher) -- South Africa , Internet in education , Online social networks , Organizational learning , Employees -- Training of , Group work in education
  • Language: English
  • Type: Thesis , Masters , MEd
  • Identifier: vital:2024 , http://hdl.handle.net/10962/d1017335
  • Description: This study focuses on two roll-outs of a, year-long National Qualification Framework (NQF) level 5, environmental education learnership in South Africa and attempts at enhancing collaborative learning at workplaces using a familiar social networking site called Facebook. This study uses the Facebook group sites created for the workplace course component of the course as one of the means of data collection. Additional interviews and focus groups with learners and administrators on both Environmental Education Training and Development Practices (EETDP) courses also informed the study. The study is located within the context of the rise of the information age, its effects on socio-ecological landscape at large and ways of using social networking sites in order to facilitate scaffolding and meaning making within zones of proximal development for environmental education learnerships. It also looks at the model of apprenticeship and workplace based learning as it is broadly located at the nexus of the SAQA-led academic inquiry into workplace based learning and professional development. It was found that the use of Facebook on the EETDP learnership allowed for collaborative learning to take place between peer to peer interactions as well as between tutors and learners. It was also noted that scaffolding processes requires both technical assistance and strong instructional input from course tutors. One of the most important findings in terms of collaborative learning and engaging within the Zone of Proximal Development (ZPD) was that learners were able to communicate more effectively and freely with both fellow learners and tutors on course after participating on the Facebook group sites. The study offers recommendations on how a social networking platform like Facebook can be utilised effectively for environmental education. The study recommends that scaffolding of workplace based tasks and concepts needs to be better integrated with the course and in both online and offline interactions between learners. It also illustrates how social networking sites can become powerful tools for creating meaning making when combined with course work.
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  • Date Issued: 2015

An empirical study on staff turnover and retention within Eskom : Eastern Cape Operating Unit

  • Authors: Chibba, Rajesh Chagan
  • Date: 2015
  • Subjects: Eskom (Firm) , Labor turnover -- South Africa -- Eastern Cape , Employee retention -- South Africa -- Eastern Cape , Job satisfaction -- South Africa -- Eastern Cape , Career development -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: vital:847 , http://hdl.handle.net/10962/d1017514
  • Description: This research paper is broken up into three sections, namely an evaluation report, a literature review and a description of the research methodology. The evaluation report section is an assessment of the factors that could contribute to staff leaving the organisation and why staff would choose to remain with the organisation. The Distribution Division of Eskom is divided into nine separate Operating Units (OU's), in line with the nine Provinces. According to an Eskom Human Resource Manager (Mjali, 2013), as at March 2012 there were 2231 employees in the Easter Cape Operating Unit, while the staff turnover for the same period was 4.53%. Of the 101 staff that had resigned for the period 01 April 2011 to 31 March 2012, there were 27 transfers, 26 resignations and 30 retirements. The balance of 18 staff that left was due to dismissals and deaths. While the statistics suggest a healthy level of staff turnover at present, given the current pressures that Eskom employees are under, it is important to investigate their future intentions and to see what Eskom can do to continue to retain their services. The literature relating to staff turnover and retention was examined to determine the meaning of the terms retention and turnover and to review the relevant turnover topics that were emerging from the exit interview data. The research conducted was quantitative in nature, and a questionnaire was distributed to all managerial staff within the Eastern Cape Operating Unit of Eskom. The questionnaire was sent electronically to the participants via email with the link to the questionnaire. Participants were requested to respond on questions relating to factors on turnover and retention, and the responses were used to assess employee's intention to either remain with the organisation or to leave. The feedback received was analysed with the use of data analysis in Microsoft Excel (2010). The results of the research showed that there were two distinct themes related to employees' intention to remain with the organisation, namely job satisfaction and career development. On the other end of the scale, themes which would cause staff to want to leave the organisation were the performance management system of the organisation, not being listened to (i.e. to the ideas and views of staff) and leadership (i.e. the way the organisation was being led). Recommendations are made to management. The study also recommends future research that can be done to get greater insight into factors relating to staff turnover and retention. A detailed review of the literature is included in Section two of the report. Only essential components of the literature are included in Section one of report. Section three of the report provided a detailed description of the research design and the research procedure that was followed.
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  • Date Issued: 2015

The regulation of agricultural subsidies in the World Trade Organization framework : a developing country perspective

  • Authors: Chigavazira, Farai
  • Date: 2015
  • Subjects: Foreign trade regulation -- Developing countries Agricultural laws and legislation -- Developing countries Tariff on farm produce -- Developing countries
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: http://hdl.handle.net/10353/1874 , vital:27569
  • Description: The Agreement on Agriculture (AoA) was adopted to eliminate the illegitimate use of tradedistorting agricultural subsidies and thereby reduce and avoid the negative effects subsidies have on global agricultural trade. However, the AoA has been fashioned in a way that is enabling developed countries to continue high levels of protectionism through subsidization, whilst many developing countries are facing severe and often damaging competition from imports artificially cheapened through subsidies. The regulation of subsidies in the World Trade Organisation (WTO) has been a highly sensitive issue. This is mainly due to the fear of compromising food security especially by developed countries. Developing countries have suffered negatively from the subsidy programmes of developed countries who continue to subsidize their agricultural sector. This position of the developing countries in the global trade system which has been described as weak, has drawn criticism that the WTO as it currently operates does not protect the interests of the weak developing nations, but rather strengthens the interests of the strong developed nations. The green box provisions which are specifically designed to regulate payments that are considered trade neutral or minimally trade distorting has grossly been manipulated by developed countries at the mercy of the AoA. Developed countries continue to provide trade distorting subsidies under the guise of green box support. This is defeating the aims and objectives of the AoA. The study examines the regulation of WTO agricultural subsidies from the developing countries’ belvedere. It looks at the problems WTO member states face with trade distorting subsidies, but focuses more on the impact these have on developing states. It scrutinizes the AoA’s provisions regulating subsidies with a view to identify any loopholes or shortcomings which undermine the interests and aspirations of developing countries. This is behind the background that some of the provisions of the AoA are lenient towards the needs of developed countries at the expense of developing countries.
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  • Date Issued: 2015

Understanding the poverty-reducing livelihoods of child support grant caregivers in Riebeeck East, South Africa

  • Authors: Chikukwa, Vimbainashe
  • Date: 2015
  • Subjects: Archer, Margaret Scotford -- Political and social views , Child caregivers -- South Africa -- Riebeek-Oos , Public welfare -- South Africa -- Riebeek-Oos , Grants-in-aid -- South Africa -- Riebeek-Oos , Poverty -- South Africa -- Riebeek-Oos , Critical realism , South Africa -- Social conditions -- 1994- , South Africa -- Economic conditions -- 1991-
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3393 , http://hdl.handle.net/10962/d1018196
  • Description: In 1994, racial domination in the form of apartheid ended in South Africa and the first postapartheid government was elected through a non-racial and democratic franchise. The new government inherited an entrenched system of racial inequality as well as widespread poverty amongst the formerly oppressed population, and it sought to address these challenges through policies of redistribution based on a new progressive constitution which emphasised the realisation of socio-economic rights. At the same time, and despite its redistributive measures, the post-apartheid government has pursued a macro-economic strategy with pronounced neoliberal dimensions. One of its critical redistributive measures focuses on social assistance to poor blacks, and this has entailed the construction and expansion of a massive social grant system including the child support grant which is received by millions of black South Africans on a monthly basis. The objective of this thesis is to examine and understand the livelihoods of child support grant recipients (or caregivers) in the context of conditions of extreme vulnerability marked by poverty. It does so by focusing on the small town of Riebeek East located in the Eastern Cape Province of South Africa. Though undoubtedly child support grant caregivers are victims of poverty, the thesis demonstrates that they are not without agency. They exist in structural conditions of vulnerability and poverty, but they nevertheless seek to manoeuvre and negotiate their way in and through their conditions of existence. This does not necessarily alleviate their poverty in any significant manner but it does show evidence of reflexivity, decision-making and responsibility in the pursuit of livelihood practices and outcomes. In making this argument, I draw upon the mega-theory of Margaret Archer (specifically, her morphogenetic approach) and the more middle-level perspective of the Sustainable Livelihoods Framework. Beyond contributing to the prevailing academic literature on the child support grant in South Africa, this thesis also hopefully makes a small contribution to controversies about structure and agency within sociology.
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  • Date Issued: 2015

The design of a new opera house for central, Port Elizabeth

  • Authors: Chilton, Marc John
  • Date: 2015
  • Subjects: Theaters -- South Africa -- Port Elizabeth -- Designs and plans Centers for the performing arts -- South Africa -- Port Elizabeth , Theater architecture -- South Africa -- Port Elizabeth
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/15356 , vital:28224
  • Description: Urban decentralization and inner city decay is a ubiquitous phenomenon of social and economic circumstance. The rise of sub-urban sprawl around new centres has encouraged urban degeneration and produced unsustainable cities, particularly in South Africa. Consequently, the loss of cultural assets in decaying historic centres, specifi cally in Port Elizabeth, reveals issues pertinent to loss of place and heritage. In combatting urban degeneration, the utilization of culture and the arts has proven to be a powerful rejuvenation strategy. The vision of the Mandela Bay Development Agency, and similar successful global precedents, suggest that a cultural precinct could effectively tackle urban decay in the historic core. This premise guides the proposal.The principal aim of this treatise is the design of a new Opera House acting as a catalyst for the proposed cultural district, based on the inner-city rejuvenation of Central. This aim is achieved by several objectives, which are explored in an effort to unveil potential and appropriate design responses: An investigation of the Opera House typology, which uncovers its dignity, vitality and signifi cance within past and present cities; An exploration of context, which reveals the opportunities to transform identity and urban cultural practise; Research into technical, spatial and physical demands of the program provide depth and root the design responses in reality. As a result, the Opera House sits as a gateway building into the precinct, as well as a cultural and physical landmark within the city. A duality of expression presents both a contrast and self-similarity in the historic context, simultaneously rooting the building in place while conveying a unique character.
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  • Date Issued: 2015

Ni(II) and Pb(II) dithiocarbamate complexes as precursors for the synthesis of HDA-capped NiS and PbS nanoparticles

  • Authors: Chintso, Thobani
  • Date: 2015
  • Language: English
  • Type: Thesis , Masters , MSc (Chemistry)
  • Identifier: vital:11349 , http://hdl.handle.net/10353/d1020201
  • Description: Ni(II) and Pb(II) dithiocarbamate complexes were synthesized and characterized by elemental analysis, UV-Vis, FTIR and TGA and some of the Ni(II) complexes and one Pb(II) were further analyzed by 1H-NMR and 13C-NMR spectroscopy. Generally all the dithiocarbamate ligands are soluble in water while the complexes were soluble mostly in solvents such as chloroform, toluene, DMSO and DCM. Based on the elemental analysis, the dithiocarbamate complexes are formulated as four coordinate (tetrahedral or square planar) compounds. However, the FTIR showed that each of the dithiocarbamate ligands acted as bidentate ligand through two sulfur atoms. The TGA of the most complexes showed one major decomposition step to give respective metal sulfide above 200 oC. In this research project, dithiocarbamate complexes were used as single source precursor for the synthesis of metal sulfide nanoparticles. We studied the optical and structural properties of metal sulfide nanoparticles using UV-Vis, photoluminescence (PL), powder X-ray diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The absorption spectra of the metal sulfide nanoparticles are blue shifted in respect to bulk material and they also showed broad emission. The XRD of the NiS nanoparticles were indexed to the cubic and rhombohedral phase, with crystallite sizes of 15 - 18 nm. The XRD of PbS nanoparticles were indexed to the face centered cubic and cubic rock salts, with the crystallite sizes 12 - 18 nm. The TEM images of the metal sulfide nanoparticles showed particles with spherical and rectangular shapes with crystallite sizes 4 - 35 nm.
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  • Date Issued: 2015

Eliciting and combining expert opinion : an overview and comparison of methods

  • Authors: Chinyamakobvu, Mutsa Carole
  • Date: 2015
  • Subjects: Decision making -- Statistical methods , Expertise , Bayesian statistical decision theory , Statistical decision , Delphi method , Paired comparisons (Statistics)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5579 , http://hdl.handle.net/10962/d1017827
  • Description: Decision makers have long relied on experts to inform their decision making. Expert judgment analysis is a way to elicit and combine the opinions of a group of experts to facilitate decision making. The use of expert judgment is most appropriate when there is a lack of data for obtaining reasonable statistical results. The experts are asked for advice by one or more decision makers who face a specific real decision problem. The decision makers are outside the group of experts and are jointly responsible and accountable for the decision and committed to finding solutions that everyone can live with. The emphasis is on the decision makers learning from the experts. The focus of this thesis is an overview and comparison of the various elicitation and combination methods available. These include the traditional committee method, the Delphi method, the paired comparisons method, the negative exponential model, Cooke’s classical model, the histogram technique, using the Dirichlet distribution in the case of a set of uncertain proportions which must sum to one, and the employment of overfitting. The supra Bayes approach, the determination of weights for the experts, and combining the opinions of experts where each opinion is associated with a confidence level that represents the expert’s conviction of his own judgment are also considered.
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  • Date Issued: 2015

Towards a changing context and performance practice of mbira dzavadzimu music in Zimbabwe

  • Authors: Chipendo, Claudio
  • Date: 2015
  • Subjects: Mbira music -- Zimbabwe Shona (African people) -- Music
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10353/6357 , vital:29588
  • Description: Mbira dzavadzimu music and performance practice has been in existence since the pre-colonial era. It played a crucial role in ritual and non-ritual activities of the Shona people of Zimbabwe. However, political, social and global influences as well as technological advancement have resulted in change of context and performance practice. Unfortunately, these have not been recorded for future generations. The major aim of the study is therefore to examine the change of context and performance practice of mbira dzavadzimu in Zimbabwe. This was achieved by reviewing mbira dzavadzimu music and performance practice within the modern setting of dandaro. I looked at change from a theoretical lens of the theory of diffusion, syncretism and mediatisation. The study was in the qualitative form superimposed on some case studies. Unstructured interviews, participant and non-participant observations were the main instruments used to collect data from both traditional and modern mbira performances. Data was also collected from museums, archives, radio and television stations. The study established that the changes in context and performance practice of mbira dzavadzimu in Zimbabwe were to a larger extent due to foreign influences such as colonialism, the coming of missionaries, modernisation, urbanisation, commercialisation, mediatisation, the use of modern technology and institutionalisation. Due to the aforementioned influences, the environmental settings, the change of context from sacred to secular, the relationship with ancestral spirits, musical practices, performance situations and quality of sound, have been modified and adjusted in response to the influences of the globalised world’s ever changing audience and performance space. In short, this has resulted in a shift of mbira performances from its traditional to modern settings, from the village to the city and onto the international scene with a new performer-audience setting. Various innovations were carried out on the instrument and its music as a result of the advent of modern technology. The use of microphones, modern amplification systems, recording studios, radio and television broadcast, audio and video cassettes, CDs, DVD, teaching of the instrument using audio and video instructional models and the use of internet sites in learning how to play mbira dzavadzimu and other instruments have become a reality. It has been evident from the study that urban and rural areas take up change in different ways and that in the former change is more pronounced than in the latter. Urban area communities are more “developed” than their rural counterparts because the former are more exposed to technological influences and the commercialisation of music. The study has also established that Zimbabwean mbira music is a good example of modern transculturality. The instrument and its music have played a major role in breaking down cultural boundaries and bringing the people of the world together for purposes of performing on the instrument. From the findings of this study, I attribute most of the changes to technologisation, for most of the changes that have taken place on mbira dzavadzimu were a result of the highly technologised way of life Zimbabweans now lead.
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  • Date Issued: 2015

Perceived undersupply of local labour in the presence of unemployment: a case of selected Sundays River Valley citrus farms, 2013

  • Authors: Chirara, Malon Tinotenda
  • Date: 2015
  • Subjects: Unemployment -- South Africa -- Sundays River (Eastern Cape) , Citrus fruit industry -- South Africa -- Sundays River (Eastern Cape) , Labor market -- South Africa -- Sundays River (Eastern Cape) , Work environment -- South Africa -- Sundays River (Eastern Cape) , Agricultural wages -- South Africa -- Sundays River (Eastern Cape) , Agricultural laborers -- South Africa -- Sundays River (Eastern Cape) , Seasonal labor -- South Africa -- Sundays River (Eastern Cape) , Migrant agricultural laborers -- South Africa -- Sundays River (Eastern Cape) , Personnel management -- South Africa -- Sundays River (Eastern Cape)
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: vital:1125 , http://hdl.handle.net/10962/d1020367
  • Description: While skilled labour shortages are common in many countries, including South Africa, mainly due to a skills mismatch, the undersupply of unskilled labour was less expected, especially in developing countries with high unemployment. The thesis utilises data on perceived worker undersupply on selected citrus farms in the Sundays River Valley (SRV), located in the Eastern Cape Province of South Africa, collected in 2013, to analyse why unemployed residents, surprisingly, do not fill up vacancies on farms. In contrast to other labour markets, farm employment is not restricted by educational levels and as workers reported, with little training the various job tasks and skills required are easy and quick to grasp. At a time the government is trying to find ways of reducing unemployment, and the SRV Municipality (2012:29) reported approximately 42% unemployment, the question arises as to why the relatively low educated residents do not take advantage of the employment opportunities on farms. According to local workers and unemployed residents, the farm job was unattractive largely because of a combination of two factors: perceived relatively low salaries partly caused by the availability of migrant seasonal workers accepting lower remuneration and poor non-wage working conditions. The survey also found that farmers preferred migrant workers because they were more productive compared to their local counterparts who were, reportedly, characterised by high absenteeism and laziness, caused mainly by a reliance on social grants and alcohol abuse. Other reasons given for the unattractiveness of the farm job included the seasonal nature of farm employment, which left workers with no source of income in the offseason, the redundancy associated with farm tasks, perceived poor treatment of workers and lack of information on UIF and Provident funds to farm workers. To address problems associated with the dislike of farm work, seasonality of on-farm employment and the reportedly relatively low income, farm managers, the local municipality and the Labour Department could possibly be involved in creating more communal agricultural projects and help provide local community members to venture into supporting alternative careers within the Hospitality, Ecotourism and Conservation Industries through training programmes. Farm managers may need to consider improving their working relationship with workers in communication and when assigning tasks. Farmers and the local municipality could also consider investing in training programmes for the unemployed residents to equip them with technical skills that can improve their chances of finding jobs.
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  • Date Issued: 2015

Microbial water quality of treated water and raw water sources in the Harare area, Zimbabwe

  • Authors: Chirenda, Tatenda G , Srinivas, Sunitha C , Tandlich, Roman
  • Date: 2015
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/76206 , vital:30520 , http://dx.doi.org/10.4314/wsa.v41i5.12
  • Description: Microbial water quality is an essential aspect in the provision of potable water for domestic use. The provision of adequate amounts of safe water for domestic purposes has become difficult for most municipalities mandated to do so in Zimbabwe. Morton-Jaffray Treatment Plant supplies potable water to Harare City and areas surrounding Harare. This study investigated microbial water quality and the impact of microbial water quality related disasters in the area supplied by the Morton Jaffray Treatment Plant. Questionnaires were distributed to household owners in Harare who receive their water from the Municipality and those who use alternate water supplies. Candidates were randomly selected from their workplace. The raw water quality of Manyame River and its tributaries was assessed. Treated water in households was assessed for microbial quality using hydrogen sulphide test and heterotrophic bacteria plate count. Raw water sources were found to be contaminated by faecal matter. Household water sources tested negative for faecal contamination but positive for heterotrophic bacteria. CFU quantities ranged from 1 to 452 CFU/m. for all samples. The WHO guidelines for domestic water sources state that water used for domestic purposes should not be contain than 100 CFU/m.. Public perceptions of water quality ranged from eunsafef to ehighly contaminatedf. A decrease in the level of aesthetic appeal resulted in residents resorting to alternative sources such as wells and rivers for their domestic water. The current state of treated water was suitable for domestic use. Pathogen monitoring of domestic water is recommended using the hydrogen sulphide test and R2A agar test.
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  • Date Issued: 2015
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