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A mobile phone solution for ad-hoc hitch-hiking in South Africa

  • Authors: Miteche, Sacha Patrick
  • Date: 2014
  • Subjects: Cell phones -- Information services , Cell phone users -- South Africa , Hitchhiking -- South Africa , Mobile communication systems -- Social aspects , Digital media -- South Africa , Information technology -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4702 , http://hdl.handle.net/10962/d1013340
  • Description: The purpose of this study was to investigate the use of mobile phones in organizing ad-hoc vehicle ridesharing based on hitch-hiking trips involving private car drivers and commuters in South Africa. A study was conducted to learn how hitch-hiking trips are arranged in the urban and rural areas of the Eastern Cape. This involved carrying out interviews with hitch-hikers and participating in several trips. The study results provided the design specifications for a Dynamic Ridesharing System (DRS) tailor-made to the hitch-hiking culture of this context. The design of the DRS considered the delivery of the ad-hoc ridesharing service to the anticipated mobile phones owned by people who use hitch-hiking. The implementation of the system used the available open source solutions and guidelines under the Siyakhula Living Lab project, which promotes the use of Information and Communication Technology (ICT) in marginalized communities of South Africa. The developed prototype was tested in both the simulated and live environments, then followed by usability tests to establish the viability of the system. The results from the tests indicate an initial breakthrough in the process of modernizing the ad-hoc ridesharing of hitch-hiking which is used by a section of people in the urban and rural areas of South Africa.
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  • Date Issued: 2014

Metal bioaccumulation and precious metal refinery wastewater treatment by phoma glomerata

  • Authors: Moore, Bronwyn Ann
  • Date: 2008-03-18
  • Subjects: Metals -- Bioaccumulation , Water purification -- South Africa , Metal ions , Water -- Purification -- Biological treatment -- South Africa , Water quality management -- South Africa , Factory and trade waste -- Purification -- South Africa , Metals -- Refining , Hyperaccumulator plants
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4097 , http://hdl.handle.net/10962/d1009441 , Metals -- Bioaccumulation , Water purification -- South Africa , Metal ions , Water -- Purification -- Biological treatment -- South Africa , Water quality management -- South Africa , Factory and trade waste -- Purification -- South Africa , Metals -- Refining , Hyperaccumulator plants
  • Description: The biosorption of copper, nickel, gold and platinum from single metal aqueous solutions by the nickel hyperaccumulator Berkheya coddii plant biomass was investigated. Potentiometric titrations of the biomass and determination of optimal sorption pH for each metal showed that nickel ions were released from the biomass into solution. The presence of free nickel ions interfered with the uptake of the other three metals and further biosorption investigations were discontinued. Three fungal isolates found colonising metal solutions were cultured and screened for their ability to remove 50 mg.l⁻¹ of copper, nickel, gold and platinum from solution and to survive and grow in precious metal refinery wastewaters. One isolate was selected for further studies based on its superior metal uptake capabilities (35 and 39 mg.l⁻¹ of gold and platinum, respectively) and was identified as Phoma glomerata. Copper, nickel, gold and platinum uptake studies revealed that nickel and gold were the most toxic metal ions, however, toxicity was dependent on pH. At pH 6 more biomass growth was achieved than at lower pH values and metal uptake increased by 51 and 17 % for copper and nickel, respectively. In addition, the production of extracellular polymeric substances played a role in base metal interaction. Precious metals were observed to be preferentially removed from solution, complete removal of gold and platinum was observed at all initial pH values, 89 % of copper was bioaccumulated at an initial metal concentration of 55 mg.l⁻¹ (pH 6) and only 23 % of nickel was removed from solution under the same conditions. Metal bioaccumulation was confirmed through transmission electron microscopy and micro particle induced X-ray emission. The effect of P. glomerata immobilised in a packed bed reactor on precious metal refinery wastewaters was investigated. It was found that the fungal isolate was not able to remove the high salt and chemical oxygen demand concentrations found in the wastewaters, however due to its ability to survive and grow in undiluted wastewater and remove metal ions from solution it may be utilised as a metal detoxification step in the treatment process train. , PDFCreator Version 0.9.0 , AFPL Ghostscript 8.53
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The informal sector : micro-enterprise activities and livelihoods in Makana Municipality, South Africa

  • Authors: Mtero, Farai
  • Date: 2008
  • Subjects: Makana Municipality , Local government -- South Africa , Informal sector (Economics) -- South Africa , Microfinance -- South Africa , Economics -- Sociological aspects , Financial institutions -- Social aspects -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:3359 , http://hdl.handle.net/10962/d1007706 , Makana Municipality , Local government -- South Africa , Informal sector (Economics) -- South Africa , Microfinance -- South Africa , Economics -- Sociological aspects , Financial institutions -- Social aspects -- South Africa
  • Description: This study examines the nature and characteristics of the informal sector within the Makana municipal area in South Africa. The focus is on the socio-economic characteristics of the informal sector operatives; operational characteristics of the microenterprises that we studied, such as longevity, employment generation, growth potential, and linkages of the informal sector with the formal sector of the economy. Extensive studies on the informal sector have been conducted in many parts of the world relative to South Africa. The key finding in most of these researches is that the informal sector is highly heterogeneous. These studies provide us with the parameters for analysing the nature and characteristics of the informal sector in the Makana Municipality. The results of the thesis show that the majority of people in Makana Municipality join the informal sector as a result of such push factors as unemployment, retrenchment and the need to survive. While there is evidence of lucrative activities amongst the surveyed enterprises, most of the informal sector micro-enterprises are concentrated in the lower segment of the sector where earnings are very low. Results from this study reveal that employment generation (beyond owner-operator) is very limited. The co-existence of a small number of remunerative activities alongside a large proportion of relatively unproductive activities is not only a sign of restricted economic potential but, most importantly, it points to the heterogeneous nature of the informal sector. Precisely, the informal sector encompasses activities which are different in terms of asset holdings, earnings, etc. From the study, it is also evident that the informal sector micro-enterprises play a crucial role in distributing goods produced in the formal sector. Evidence indicates that these micro-enterprises are Iinked to the formal sector. The idea of a 'second economy' devoid of linkages with the 'first economy' is of limited heuristic value. Thus, the 'second economy' is an extension of the first.
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  • Date Issued: 2008

South Africa and the International Criminal Court: investigating the link between complimentarity and implementation

  • Authors: Kulundu, Kenneth Wanyama
  • Date: 2006
  • Subjects: International Criminal Court , International criminal courts , International crimes , International law -- South Africa , South Africa -- Law and legislation
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: vital:3679 , http://hdl.handle.net/10962/d1003194 , International Criminal Court , International criminal courts , International crimes , International law -- South Africa , South Africa -- Law and legislation
  • Description: Complementarity, the organizing principle of the International Criminal Court (ICC), is a largely untested concept in terms of its ability to instigate State compliance with the Rome Statute of the International Criminal Court. The ICC made its debut at a time when States were routinely accused of non-compliance with international law, particularly international criminal law. Due to perennial concerns over the protection of State sovereignty, an ingenious system of allocation of competencies between States and the ICC was evolved. This is embodied by the principle of complementarity. At the heart of complementarity is an arrangement by which States Parties to the Rome Statute of the ICC are regarded as the prime fora for the prosecution of crimes of grave concern to the international community. In the event of inaction, however, the ICC is mandated to wrest specific cases from the jurisdiction of national courts and try them. In effect, a carrot-and-stick mechanism has been built into the Rome Statute to induce States to comply with the Statute. This thesis examines the principle of complementarity from a theoretical perspective, bearing in mind contemporary international law structures and institutions. A better understanding of the theoretical assumptions of complementarity, it is suggested, will foster a more effective application of the tenets of the Rome Statute within the municipal system. The thesis argues that complementarity is a catalyst for implementation of the Rome Statute only to the extent to which it alters or re-defines well established and encumbering procedures and norms within the municipal system. In this regard, although South Africa’s status of constitutional democracy may be reason to expect that the obligations imposed by the Rome Statute will be observed, that very fact may increase the inclination to preserve the “baseline of conduct” rather than be swayed by the Rome Statute. An illustrative excursion into South African rules and norms is undertaken, after which the argument is advanced that not much change has been effected to the South African legal landscape through implementation of the Rome Statute. The sole exception to this is the issue of prosecutorial discretion. On this, the South African legislature has uniquely crafted a mechanism for ensuring accountability, presumably with a view to ensuring that South Africa is always able to prosecute the crimes concerned. However, the thesis cautions against complacency, arguing that the tension between national law and international obligations may yet play itself out, owing to insufficient attention to the role of national courts in giving effect to the Rome Statute. The act of implementation may be a response to stimuli such as the perceived need to avoid civil liability for international crimes, or the general inertia of implementing human rights instruments. Therefore, the carrot-and-stick mechanism may be lacking in the compulsive qualities it is presumed to have. Through an exploratory survey of South African law, the thesis illustrates that prosecutorial accountability is the major factor in determining whether a State has fully complied with is obligations under the Rome Statute. However, it also points out that the way courts of law apply the new norms in municipal systems in the future will be crucial.
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  • Date Issued: 2006

Processes and products in the kimberlitic crater facies of the south lobe, Jwaneng Mine, Botswana

  • Authors: Machin, Kimberley
  • Date: 2001
  • Subjects: Kimberlite -- Jwaneng (Botswana)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4995 , http://hdl.handle.net/10962/d1005607 , Kimberlite -- Jwaneng (Botswana)
  • Description: The Pennian (~ 245 Ma) Jwaneng kimberlite, situated in southern Botswana, comprises three steep-sided pipes that coalesce approximately 100m below the present day surface to fonn a 54ha body. These pipes have been labelled the South, Centre and North Lobes. The kimberlites intruded a thick sequence of Proterozoic shales, dolomites and sandstones and a thin veneer of consolidated to poorly consolidated mudstones and siltstones of the Karoo Supergroup. Although the shapes of these pipes are comparable to other southern African pipes, they are filled predominantly with crater facies volcaniclastic kimberlite. No tuffisitic kimberlite breccia, the characteristic rock type of the diatremes of other southern African pipes, has yet been identified. The Jwaneng kimberlite thus represents an exception to the standard model for southern African kimberlites, implying that different processes need to be invoked to explain its fonnation. The present study involves a detailed volcanological and sedimentological analysis of the volcaniclastic fill of the Jwaneng South Lobe. Two principal and distinct lithofacies have been identified: the quartz-free RVK facies and the quartz-bearing QRVK facies. Both facies include fine to coarse grained, predominantly massive and subordinate chaotically bedded deposits. The volcaniclastic rocks have been classified as resedimented volcaniclastic kimberlite (RVK) , since their deposition is ascribed to mechanisms dominated by mass flow processes. Based on certain characteristics and differences between the two principal facies, and their spatial distribution within the pipe, they are interpreted as being the products of at least two separate eruption episodes. Certain characteristics (e.g. }hape, granularity~ of the juvenile· magma clasts III the volcaniclastic kimberlite suggest complete crystallisation and devolatilisation of the magma at depth prior to explosive fragmentation. A scenario in which this might have occurred, and which led to catastrophic explosive eruption and pipe excavation is proposed. Explosive eruption and associated tuff cone formation is followed by resedimentation of the material back into the pipe by mass flow processes. Mass flow processes are dominated by debris flow, with lesser grain flow, hyperconcentrated flow and subaqueous mud flow and suspension settling of muddy kimberlitic sediments. Geochemical analyses of the latter indicate a high degree of contamination and weathering, and mixing between pristine kimberlite and silicic shale/mud compositions. Failure and collapse of parts of the underlying pipe walls yielded megablocks of poorly consolidated Permian Karoo mudstone in the peripheral zone of the pipe. This source of the megablocks is supported by their bulk chemical composition. Minor phreatic/phreatomagmatic eruptions are suggested by the presence of rare accretionary and armoured lapilli within both the QRVK and RVK facies. Subsidence of the volcaniclastic pipe fill, inferred mainly from the oversteepened dips of the bedded QRVK and RVK facies, may be related to gravity-induced compaction, late-stage phreatomagmatic eruptions or eruption ofthe adjacent Centre Lobe.
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  • Date Issued: 2001

Social workers perceptions on unionisation and collective bargaining : an exploratory study of the central region of the Eastern Cape

  • Authors: Dyakala, Tumeka
  • Date: 2000
  • Subjects: Social workers -- South Africa -- Eastern Cape -- Attitudes , Labor unions -- South Africa , Collective bargaining -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSocSc
  • Identifier: vital:695 , http://hdl.handle.net/10962/d1006405 , Social workers -- South Africa -- Eastern Cape -- Attitudes , Labor unions -- South Africa , Collective bargaining -- South Africa
  • Description: This study explores primarily the views of social workers in the Central region of the Eastern Cape on unionisation and collective bargaining, and at a secondary level the views of their employers and of the trade unions organising social workers, regarding social workers' involvement and non-involvement in these processes. It examines the paradox of compatibility of professionalism and unionism. There are two schools of thought regarding compatibility of professionalism and unionisation one views these concepts as antagonistic whilst the other views these concepts as complementary. Some social workers have been reluctant to participate in trade unions in the past until recently. Reasons advanced for their recent accelerated involvement in trade unions are explored in this study. Social workers views on the Labour Relations Act 66 of 1995 as the source of the legal framework, within which trade unions and employers interact, through the process of collective bargaining are explored. Proposed alternative mechanisms to these processes as perceived by social workers are closely examined. Semi-structured, self administered questionnaires were distributed to social workers whilst semi-structured interviews were conducted with employer representatives and trade union officials. This helped the researcher to have a broader view of the situation. Findings point to a scenario of disunity of both employers and employees in the social work profession. The study is a pioneering effort in the Central region and sets a way forward for further exploration of this subject. It is hoped that this study will make a worthwhile contribution to the social work profession's industrial relations field
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  • Date Issued: 2000

The artificial recharge of urban stormwater runoff in the Atlantis coastal aquifer

  • Authors: Wright, Alan
  • Date: 1992
  • Subjects: Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4817 , http://hdl.handle.net/10962/d1005491 , Atlantis water resource management scheme , Urban hydrology -- South Africa , Urban runoff -- South Africa , Storm sewers -- South Africa , Water resources development -- South Africa
  • Description: The thesis covers the investigation of the storm water runoff and artificial recharge components of the Atlantis Water Resource Management Scheme in the Southwestern Cape. The objective of the study was to obtain an in-depth knowledge of the process of artificial recharge of urban storm water runoff, in order to identify the most efficient recharge management strategy for the Atlantis aquifer. To achieve the objective it was necessary to first study the existing knowledge on urban storm water hydrology and artificial recharge by spreading, and to create a conceptual model of what might be expected. The study area was then investigated to examine how closely the actual situation was reflected by the conceptual model, enabling recommendations to be made for the sound management of the system. The stormwater runoff component was found to differ from most urban hydrological studies as a result of its large baseflow component. The sandy nature of the catchment, small percentage area of effective impervious surface, and high groundwater table resulted in the baseflow constituting more than 40% of the total storm water runoff and accounting for over 60% of the pollution load. The "first flush" effect established as a major source of pollution in other studies, was found to be of minor significance in this study area. The overall stormwater quality (excluding the noxious industrial baseflow) was found acceptable for artificial recharge within the study area, although the baseflow from the industrial sub-catchments showed the potential for being a major source of pollution in the future. The treated wastewater used for artificial recharge prior to 1987 was found to be unacceptable for recharge purposes. The treated industrial effluent should under no circumstances be recharged up-gradient of the Witzand well field. The treated domestic effluent although of a poorer quality than the resident Witzand well field groundwater could be recharged in order to boost recharge volumes and form a buffer against further intrusion by the poor quality groundwater from the Brakkefontein area. This would however only be acceptable if strict water quality control is maintained and recharge does not take place west of the present basin. The recharge basin was found to be well situated with respect to influencing the Witzand wellfield and maintaining a groundwater buffer against poor quality groundwater flow from the northeast towards the central area of the wellfield. Unfortunately the surrounding low-lying topography and sandy retaining walls have resulted in return flow and raised groundwater-levels. The raised groundwater mound does not comply with the conceptual model and together with the sandy nature of the unsaturated zone resulted in less effective purification during infiltration. The practice of letting large portions of the basin floor dry-out during summer was shown to be beneficial and the periodic cleaning of the deeper portions of the basin essential. The artificially recharged water was found to have influenced the upper portion of the aquifer well beyond the West Coast Road. The study of groundwater quality being a good method for tracing artificially recharged water. The groundwater quality has improved as a result of artificial recharge since the removal of treated wastewater from the recharge basin. The groundwater was (ii) found to be very responsive to the slightest changes in recharge basin water quality or/and quantity. Management of the recharge basin therefore had to be very much of a compromise between qualitative and quantitative approaches. The present approach of recharging all the stormwater runoff throughout the year providing the most efficient compromise under the present conditions. The study revealed that the most efficient recharge management strategy would be the recharge of treated domestic sewage effluent in the present recharge basin and all residential storm water runoff plus industrial "storm flow" stormwater runoff in a new recharge basin located northwest of the present basin. Strict water quality control must be maintained on the water discharged into the basins and an annual wet/dry cycle implemented within the basins to boost infiltration. The entire system should continue being monitored to safe guard the groundwater resource from pollution and over exploitation.
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  • Date Issued: 1992

Mineralogy and petrology of the Townlands iron-rich ultramafic pegmatite

  • Authors: Phillips, David
  • Date: 1985 , 2013-09-09
  • Subjects: Ultrabasic rocks -- South African -- Rustenburg , Platinum ores -- South Africa -- Rustenburg , Pegmatites -- South Africa -- Rustenburg , Mines and mineral resources -- South Africa -- Rustenburg
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:5040 , http://hdl.handle.net/10962/d1007617 , Ultrabasic rocks -- South African -- Rustenburg , Platinum ores -- South Africa -- Rustenburg , Pegmatites -- South Africa -- Rustenburg , Mines and mineral resources -- South Africa -- Rustenburg
  • Description: The Townlands iron-rich ultramafic pegmatite is a relatively large pipelike body situated in the western corner of Rustenburg Section, Rustenburg Platinum Mines. It is characterised by a strong negative magnetic signature and transgresses the noritic layered sequence of the upper critical zone of the Bushveld Complex. The layered rocks are downwarped in the vicinity of the pipe and are in sharp contact with the pegmatitic material. The pegmatite varies in composition between dunite and wehrlite, with the marginal zones being more wehrlitic in composition. Olivine (Fo₃₀ - Fo₅₂) and clinopyroxene (Wo₄₅En₃₀Fs₂₅ - Wo₄₅En₃₇Fs₁₈) are the dominant constituents and accessory phases include ilmenite, Ti -magnetite, apatite, amphiboles, chlorite-group minerals, biotite, ilvaite and a host of unusual ore minerals. The Fe-Ti oxides exhibit exsolution textures typically found in slowly cooled igneous rocks and temperatures of formati on are consi dered to be in excess of 800°C. The UG2 chromitite leader layers intersected by borehole TLP.l are enriched in Fe and Ti and exhibit compositions intermediate between chromite and Ti-magnetite. The ore mineral assemblage includes a primary sulphide assemblage consisting of troilite, chalcopyrite, cubanite and pentlandite, and an array of unusual phases formed by late-stage secondary processes. The unusual sulphides mooihoekite and haycockite, that occur in certain parts of the pegmatite, are considered to have formed by partial replacement of the primary assemblage and a possible paragenetic sequence is discussed. Mineral compositions and whole rock geochemical data are consistent with an origin for the pegmatite by crystallization from a fractionated melt. It is suggested that intercumulus fluids, trapped during the crystallization of the noritic layered sequence, accumulated in an area of structural weakness, in response to an increasing overburden pressure and/or tectonic activity. Evidence is also presented that indicates that the Townlands pegmatite may consist of at least two separate, but adjoining pegmatite bodies. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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  • Date Issued: 1985

The tectonic framework of magmatism and mineralization in the western United States

The thermal decomposition of silver oxide

  • Authors: Herley, Patrick James
  • Date: 1960
  • Subjects: Silver oxide -- Thermal properties , Decomposition (Chemistry)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: vital:4525 , http://hdl.handle.net/10962/d1015017
  • Description: [From Introduction]. The thermal decomposition of solids is characterized by the formation and growth of nuclei at sites on the surface of the solid or within the crystal lattice. Such nuclear formation is favoured by disorganisation of the crystal either by mechanical damage, or by the presence of impurities. Disorganisation results in positions which have a high thermodynamic instability. The nuclei are likely to be formed initially at the corners and the edges of the crystal since these are more prone to damage. Careful handling and storage in vacuo often leads to a large reduction in their number, while deliberate scratching of the surface facilitates their production. The number of potential sites for nuclear formation is also increased by pre-irradiation with ultra-violet light, though there are indications that a different type of nucleus may be produced. Nucleation can be facilitated by pre-irradiation with electrons, neutrons, X-rays, gamma-rays and atomic particles. The nature of the nuclei is not always clearly defined, but it is generally accepted that they are composed of solid reaction products e.g. in the decomposition of barium azide and silver oxalate, nuclei of metallic barium and silver, respectively, are formed.
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  • Date Issued: 1960
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