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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Strategic implication of a segmentation and positioning model for the South African gold narrow reef mining market.

Landman, G. V. R. 17 August 2012 (has links)
M.Comm. / Many variables exist that influence buyer behaviour in the narrow reef gold mining market. Since some variables are real but subjective in nature, such as the opinion and charisma of mine managers or influential individuals, it is difficult to quantify and analyse them. The question is ? Which variables, 8 quantifiable or not, are more dominant in shaping buyer behaviour and how should they be prioritised? What is needed is a logical segmentation model which reflects true buyer behaviour in order to shape future strategies in AEL so that the overall company objectives can be met. Each segment should then be analysed and considered regarding attractiveness in satisfying needs and the ability to add value both to the customer and to AEL. It is also required to target market segments and develop a marketing mix for them so that AEL is correctly positioned to retain the markets it choose to compete in. The problem is the failure to identify market areas of similar response which are relatively stable and can be used to select areas where maximum value can be added to the customer and to the company and can be used to shape and define future direction. The following objectives have been set for this study:The establishment of a market segmentation model which will identify and explain the basis of similarities and differences in buyer behaviour groups which is sufficiently large and stable in order to focus future strategies. - The interpretation of the segmentation model in the light of the strengths, weaknesses, opportunities and threats of the company in order to target markets best suited to the potential of the company. - Development of strategies and positioning in the target markets to strengthen the chance of success.
22

Characterisation and beneficiation of coal from the New Vaal Colliery, Sasolburg-Vereeniging Coalfield, South Africa, through the application of automated mineralogy

Pretorius, Donavan Johannes 11 November 2015 (has links)
M.Sc. (Geology) / The purpose of this study was to assess the MLA’s ability to characterise (e.g. modal mineralogy, elemental assay, particle size distribution, particle density distribution and mineral associations) a coal product from New Vaal Colliery, with the aim to determine any liberation and beneficiation characteristics. In general the MLA assessment on coal is comparatively new and novel, especially at Spectrum (University of Johannesburg), hence research in this regard is required. For the first time New Vaal coal product was characterised with the MLA 600 FEG SEM. The coal product supplied to Lethabo Power Station for the study’s samples, consisted of Top Seam and Middle Seam coal from New Vaal Colliery which is located in the Cornelia subbasin of the Vereeniging-Sasolburg coalfield, South Africa. The proximate analysis characterised the coal as a high-ash (42.25% air-dried) and low calorific value (13.92 MJ/kg air-dried) product. Chemically SiO2 was the most abundant oxide followed by Al2O3 for the XRF analysis, which was mostly derived from the abundant kaolinite clay mineral (determined by petrography, XRD and MLA analysis). Mineralogically inertinite was the most abundant coal maceral encountered during the petrographic analysis. With geochemical characterisation, chalcophile, siderophile, lithophile and radioactive trace elements were found to be mostly comparable to the global average.
23

The nature and origin of gold mineralization in the Tugela valley, Natal Structural and Metamorphic Province

De Klerk, Ian Duncan January 1991 (has links)
The project area is situated within the Tugela Valley, located in the Northern Marginal Zone of the Natal Structural and Metamorphic Province, and this work outlines the different styles of gold mineralization found in the Tugela Valley. Two different styles have been recognized and both have economic significance:- 1) Epigenetic shear zone-hosted gold occurs in late-stage relatively undeformed thin quartz veins confined to shear zones, and is present in both the greenschist facies Natal Thrust Belt and the amphibolite facies Natal Nappe Complex. However the vast majority of these occurrences are concentrated within the thrust front (i.e. the Natal Thrust Belt). The gold grades (up to 7 g/t) and the hydrothermal alteration assemblages associated with the epigenetic deposits have been documented. 2) An as yet unrecognized occurrence of syngenetic gold mineralization is found associated with the sediment-hosted exhalative massive, to semi-massive, sulphides of the iThuma prospect, located within the amphibolite facies Natal Nappe Complex. Here gold (up to 3 g/t) is concentrated together with the main sulphide are, as well as some gold enrichment (230ppb) in the hydrothermally altered footwall feeder pipe. It is proposed that the epigenetic mineralization was formed as a consequence of the northward directed abduction of the major thrust slices of the Natal Nappe Complex. This increased the permeability of the rocks and provided channelways for the focussing of fluids. Deposition took place at the thrust front where metamorphic hydrothermal fluids interacted with meteoric water.
24

A hydrogeological investigation of the Grootegeluk mine

Johnstone, Andrew Clifford January 1989 (has links)
The study concerns an assessment of the hydrogeological impact of an open cast coal mine in the North Western Transvaal Province of South Africa. The hydrogeological impact of the mine is assessed in terms of groundwater quality and levels. A monitoring system was installed to enable the present and future impact of mining operations on the hydrogeological regime to be assessed. Grootegeluk Mine is situated in the Waterberg Coal Field of South Africa and began production in 1980. The mine extracts fifteen million tons of mine material annually from a single open pit. Forty percent of the mined material is saleable product and the remaining sixty percent is stacked on discard dumps. The Daarby fault forms the northern boundary of the open pit and serves to bring the younger Letaba and Clarens Formations into contact with the older Beaufort and Ecca Groups. The mine discards are deposited north of the fault on a different hydrogeological environment from which they are mined. Dewatering of the mine open pit has resulted in a steady decline in water levels in the Ecca Group, south of the Daarby fault. In contrast, water levels north of the Daarby fault in the Letaba and Clarens Formations have risen. The short term hydrochemical impact of the mine discard dumps and slimes dams have resulted in a rise in the calcium, sulphate, chloride, fluoride and nitrate concentrations of the ambient groundwater . The longer term hydrochemical impact from the waste dumps, acid mine drainage, is not evident at present in the groundwater below the waste dumps. However, it is expected to manifest itself during the next ten years. A monitoring system was installed at the mine to allow groundwater levels and quality to be monitored. By measuring groundwater quality and levels the impact of the mine on the regional hydrogeology can be monitored and assessed presently, and during the next forty years of production. Monitoring will also enable the timeous implementation of remedial measures at an early stage and eliminate the need for large late stage "clean up" operations. Future monitoring of both water levels and quality will be crucial in evaluating the mine's impact on the regional groundwater regimes over the next forty years of production. The remedial measures recommended for leachate presently emanating from the waste dumps and slimes dams north of the Daarby fault, are a number of collector wells drilled into the basalts and sandstone north of the Daarby fault. The proposed positions of the wells (boreholes) are as close as possible to the dumps and slimes dams with expansion taken into consideration. The boreholes should be designed to lower the water level in the vicinity of the dumps in order to create a nett groundwater gradient towards the dumps and as a result, halt the spread of leachate away from the dumps. Grootegeluk plans to backfill the open pit with plant discards on completion of the mining of zone 2. The backfilled material will consist of the currently produced plant waste and will be covered with overburden and topsoil. It is expected that the backfilling will have a major impact on groundwater quantity if no remedial measures are implemented. The two remedial measures discussed are chemical treatment of the discard material before backfilling or the continual abstraction of water from the pit resulting in a nett groundwater inflow into the pit. No material from the present waste dumps and slimes dams will be transported into the open pit as backfill material
25

An evaluation of small scale open cast mining of UG2 in the Bushveld complex

Mooney, David G January 1997 (has links)
The current weak state of the platinum market, as well as the large inventory of platinum group metals held by Russia, necessitates that the South African platinum mining industry must carefully evaluate the benefits and disadvantage of small-scale mining of shallow, open castable ore resources. Until the late 1980's, these resources were ignored due to the metallurgical complexities of treating oxidized ore, as well as the mind set that existed within the South African mining industry which militated against open cast mining in the Bushveld. During the latter part of the 1980's and early 1990's, advances in the metallurgical treatment of oxidized ore, specifically the UG2, as well as operational problems, created the impetus to begin the exploitation of these resources. Small-scale open cast mining has become viable due to the development of suitable mining methods that facilitate mining practices acceptable to the Department of Mineral and Energy Affairs, in terms of environmental legislation. Metallurgical advances and growing experience, especially with respect to the UG2, enables reasonable platinum group metals recovery from oxidized ore. The problems experienced in doing this can, and are being overcome. With growing public awareness of environmental issues, particularly related to the mining industry, the requirement to ensure that the small-scale open cast mine site is well managed is paramount. A methodology for the evaluation is presented along with a case study of a small-scale UG2 open cast pit. Evidence is presented that shows that these small-scale open cast mining operations are extremely profitable and require minimal capital expenditure. However, caution is advised when evaluating Merensky Reef open cast operations because of the problems that they present.
26

Corporate reputation in the South African diamond industry : a multi-stakeholder perspective

Ngcobo, Sakhile Glen January 2016 (has links)
A thesis submitted to the Faculty of Commerce, Law and Management, University of the Witwatersrand in fulfilment of the requirements for the degree of Doctor of Philosophy / Lack of common understanding of corporate reputation in the diamond industry in South Africa has attracted a lot of interest in this aspect of the mining industry. The recent Marikana Massacre in the platinum belt in the Rustenburg area at Lonmin Mine in 2012, together with on-going debates on resource nationalisation and negative relations between mine communities and diamond mining companies have prompted the call for more research in reputation management in the mining industry in South Africa. The purpose of this research is to define the meaning of corporate reputation in the diamond industry, to understand key perceptions of the diamond industry, to identify key effects of corporate reputation in the diamond industry and to evaluate key management approaches to corporate reputation in the diamond industry from multi-stakeholder perspectives. Mixed methods research methodology was used in this study, comprising quantitative and qualitative data collection and data analysis. Key findings include that there is no one single definition of corporate reputation. Each stakeholder has his/her unique definition which is based on his/her own assessments of the organisation, the past and future actions of the corporation, and their experience and perception of the organisation. Poor relations between mine communities and diamond companies; prospects for the collapse of the Kimberley Process (KP); violent strikes; environmental issues, including rehabilitation of old mines; poverty and high unemployment in the mining communities; failure of BEE transactions in delivering real value to the mine employees and local communities; illegal mining; the rise of synthetic un-natural diamonds and negative perceptions of the diamond industry in South Africa are the current major challenges and risks affecting the diamond industry in South Africa. This study concludes that positive corporate reputation would result in improved investor confidence, higher levels of attracting and retaining top level talent in the organisation, improved attraction of customers, better relations with communities and improved stakeholder relations. The study did not find evidence proving that a positive reputation will result in higher prices for diamond products. It found that corporate reputation management initiatives in the diamond industry are not well understood and, as a result, they are not delivering the full results as expected. ii | P a g e Effective stakeholder relations management with a special focus on community engagement including youth groups’ involvement in the mining towns; targeted social investment programmes with special focus on enterprise development and effective management of industry perceptions are identified as the most critical steps to be adopted in the diamond industry in order to improve its reputation. / GR2018
27

A study of the correlation between dragline diggability and blasting technology at Syberfontein colliery.

Frimpong, Mensah. January 1994 (has links)
A project report submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master ofil science in Engineering. / Given the high capital intensity of the dragline operation, the mine can not afford to" tolerate fragmentation problems with its concomitant low dragline productivities. At Syferfontein colliery very large boulders and completely unfraqmented sections resulting in Low digging efficiency of the dragline were encountered in the interburden blast, This project, investigates the causes of the blasting related problems with an intent of improving dragline productivity at the minimum possible cost. This is achieved through blast monitoring, evaluation of the existing practice (blast design) using empirical relations, fragmentation assessment using a model, analysis of operators performance and dragline availabilities. Dragline productivity is evaluated in the light of the various productivity indices , viz, fill factor, fill time and BCM/H. The results indicated explosive incompatibility with the blasting environment and. questionable practices regarding blast design and Delay performance. Engineering field controls such as reduction in drill pattern, reduction of VODof explosive and improvement in draqline utilisation are found necessary. Contributing 61% to the total cost I concentrating on reducing draqline cost must receive preference over drilling and blasting cost as it would produce the most tangible advantage in any cost reduction effort. Regression equations relating cbst and productivity are established. / Andrew Chakane 2018
28

Assessing how an adaptive management approach was incorporated in the mitigation strategies for acid mine drainage discharge in the Witwatersrand basin

Rantsieng, Masekantsi Rahab January 2018 (has links)
School of Mining Engineering, Centre for Sustainability in Mining and Industry, University of the Witwatersran, 2018 / The predicaments faced by humanity today differ from the past due to the increasing scale of human influence, complexities and uncertainties (Allen et al., 2010), which limit management options. Adaptive management is based on the philosophy that knowledge is incomplete i.e. there will always be uncertainty and unpredictability in the behaviour and dynamics of complex social-ecological systems. Given the complexity of the South African mining industry, this research aimed to explore the link between management and science by assessing the extent to which an adaptive management approach had been incorporated into short-term and long-term mitigation strategies for the discharge of acid mine water in the Witwatersrand Basin. The methodology included a review of the adopted mitigation strategy document, a literature review of adaptive management literature and an in-depth analysis of a case study using nine interviews, conducted with key informants and contributors from the government, an educational institution, industry (mines currently dealing with the issue), and civil society. An inductive and descriptive approach was followed to gather and analyse data to formulate answers to the research questions. The findings of the study indicated that the efforts that went into designing the short-term solutions were limited due to the lack of communicating amongst stakeholders and the failure to incorporate a value-based approach. Results also showed that complexities and uncertainties were not addressed to allow for adaptation to constant change. It was found that the short-term interventions had no managerial flexibility which limited learning. Insufficient monitoring and a lack of transparency regarding the dissemination of monitoring results were highlighted. Moreover, experimental efforts were limited due to lack of capacity and funding. In conclusion, although the long-term strategy incorporated some aspects of adaptive management, the short-term mitigation measures were reactive rather than proactive. It is recommended that on-going training and good communication are maintained amongst stakeholders. Recommendations for economic constraints include the sharing of costs through partnerships, evaluating trade-offs between costs and effectiveness and investigating cheaper measuring methods for monitoring. Risk-averse initiatives such as conducting risk assessments during pilot studies and accommodating for different project scales can be employed to mitigate against resources that are sensitive to change. / XL2019
29

THE PROVISION OF SUPPORT MATERIAL TO ASSIST FET PHASE ACCOUNTING EDUCATORS IN THE FREE STATE PROVINCE

MEYER, FREDERICK JOHANNES January 2008 (has links)
Thesis (Ph. D.) - Central University of Technology, Free State, 2008 / This study primarily focuses on the factors that should be taken into account when developing Learning and Teaching Support Material (LTSM) to be used by FET Accounting educators to improve the results of their learners. In order to accomplish this aim, literature from published books, textbooks, guidelines and syllabi from the Department of Education, speeches and articles on the internet, interviews and questionnaires were used in capturing data to establish the essence of Accounting and Accounting principles, to determine the educational changes regarding the curriculum that were made and the influence of these changes on the Accounting syllabi for the FET phase, to identify the factors that hamper the improvement of FET Accounting results in schools and to identify, describe and analyse a curriculum and LTSM. A triangulation methodology was employed in this study where qualitative data (interviews) and quantitative data (questionnaires) were captured. Through the interviews with the Learning Facilitators of Accounting and questionnaires completed by Accounting educators, it became clear that a lack of LTSM exist in Accounting. Accounting educators indicated that they are in dire need of LTSM for the FET phase to be able to improve the results of their Accounting learners in tests and examinations.
30

Worker participation structures on a gold mine

Ralefeta, Willie Moyahabo 14 August 2012 (has links)
M.Com. / The objective of this study was to address problems pertaining to the effectiveness of hostel representative structures within the mining industry. As part of the study, it was thought pertinent to interview hostel representatives themselves, in order to establish areas in which improvement could be made. The actual approach was to determine the roles and responsibilities of the hostel representatives and gain suggestions from hostel representatives themselves on the causes of inefficiencies of hostel representative structures. In addition, hostel accommodation preferences were determined; by identifying major functions of the hostel representatives, problems reducing their effectiveness, hostel structures which are more effective, and the reasons of their effectiveness. Views of management and representative structures were also determined; this was done by identifying the degree of trust in both mine and hostel management to look after the interests of the hostel representatives. In addition, effectiveness of various hostel representative groupings was determined. Different forms of worker representative structures on the mine were identified and discussed. The theoretical model of forms of worker participation was discussed to further assist in conceptually clarifying the wide field of worker participation. The actual results reported from this study seem to indicate that: hostel representatives' major functions are; disciplinary, communication, domestic, legal, dispute resolution and hostel management deputising functions. Problems that reduce the effectiveness of the hostel representatives were hostel intruders and undisciplined residents, lack of maintenance in the hostel, lack of protective clothing, mine management undermining of the hostel representatives, hostel committee's failure to follow constitution, a lack of promotional opportunities, power struggle union and management structures. In addition, having to consult with other representative structures caused delays in case settlement. Lack of remuneration of the hostel representatives reduced the effectiveness of the hostel representatives. Role conflict between underground work and representative role was also a hindrance to the hostel representatives. Failure of the hostel representatives to attend meetings was also a cause which reduced the effectiveness of the hostel representatives. The Tribal Prefect is considered as more effective than the Block Stewards, the Administration Assistants and the Hostel Committee Members. The Administration Assistants are perceived as most effective in looking after the interests of hostel employees than other hostel representatives.

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