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Critical success factors of South African construction companies

  • Authors: Lombard, Daniel
  • Date: 2019
  • Subjects: Construction industry -- Planning -- South Africa , Construction industry -- Management Construction industry -- South Africa Success in business -- South Africa
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/42229 , vital:36637
  • Description: The aim of the study was to identify the driving forces of the South African construction industry for registered cidb Grade 9 companies. The next objective was to identify the critical success factors (CSF) that are required to be used by the forward-looking and pro-active cidb Grade 9 companies. The most important critical success factors were then highlighted to form a core group of CSFs for construction industry. From this core group of CSFs an attempt was then made to identify business strategies that can assist companies in gaining a competitive advantage in the construction industry of South Africa. The research was based on the problem statement from which the sub-questions and hypothesis were derived. The primary data was collected through a mixed method of quantitative and qualitative research. A ontological philosophy was used for the research to effectively collaborate with the mixed method of research used. The approach of the research was a mix of both inductive and deductive, as it pursued to identify the forces and factors dominating the construction industry. The study subsequently determined what business strategies best suit these results. The research questionnaire was distributed between senior managers of grade 9 cidb construction companies and found that the most eminent driving forces of the industry are political and government decision making, as well as economic conditions. The CSFs showed a clear indication of what the respondents perceived as the most important factors. Although there have been many advances in technology and processes over the years, the most important CSF for contractors are still the processes of bidding and tendering and the factors relating to these. The qualitative research portion of the study was an investigation on what business strategies were best related to the key driving forces and most important CSFs. Interviews were held with directors of cidb grade 9 construction companies. The themes that were identified from the analyses of the qualitative data were that business strategies relevant to differentiation, diversification, cost leadership or hybrid were seen as the most effective for construction companies. The bidding and tendering process is not merely the same process that it used to be. Frequent reviews of what the industry is going through have also become a major necessity. The research was limited to companies registered as grade 9 with the Construction Industry Development Board. The research is seen as valued as the construction industry is highly important towards the development of the economy of a country and the impact that it has on communities.
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  • Date Issued: 2019

Cultural clusters as a local economic development strategy in rural, small town areas: the Sarah Baartman District in the Eastern Cape of South Africa

  • Authors: Drummond, Fiona Jane
  • Date: 2019
  • Subjects: Cultural industries -- South Africa -- Eastern Cape , Creative ability -- Economic aspects -- South Africa -- Eastern Cape , Arts -- Economic aspects -- South Africa -- Eastern Cape , Culture -- Economic aspects -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape , Economic development projects -- South Africa -- Eastern Cape
  • Language: English
  • Type: text , Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10962/71568 , vital:29879
  • Description: It is increasingly recognized that the cultural and creative industries (CCIs) can play an important role in economic growth and development. Governments around the world, including South Africa, are implementing culture‐led economic growth and development strategies on national and regional scales. CCIs tend to cluster around large cities because of existing hard and soft infrastructure such as networking advantages and access to skilled labour, however, much less is known about the potential of the CCIs to drive rural development. This thesis thus investigates the potential of the CCIs to cluster in small towns and rural areas. Moreover, it examines the relationship between the CCIs and socio‐economic development. The CCIs have been touted as a catalyst for economic growth and development and so have often been used in urban regeneration schemes. The Sarah Baartman District (SBD) of South Africa’s Eastern Cape has identified culture as a potential new economic driver. Establishing a new development path is necessary as the former economic mainstay, agriculture, has declined in the region, creating poverty and unemployment problems. However, the SBD has only small towns which, according to the literature, are not suited to CCI clustering. Despite this, there is evidence of cultural clustering in some of the SBD’s small towns like Nieu Bethesda and Bathurst. This research therefore conducted an audit of the CCIs in the district and used geographic information systems (GIS) to map their locations by UNESCO Framework of Cultural Statistics (FCS) domains in order to determine the extent to which clustering has occurred in a small town setting. The audit identified 1 048 CCIs operating in the district and determined that clustering is possible within some small towns, depending on their demographic, economic, social, geographic and historic characteristics. For small towns where clusters exist or the potential for cluster formation is present, the domains in which the town holds a comparative advantage, based on domain proportions and location quotients, should be pursued for local economic development (LED). In this case, Visual Arts and Crafts and Cultural Heritage were prominent throughout the district while Design and Creative Services and Performance and Celebration had small regional concentrations. Theory suggests that the presence of CCIs is linked to higher levels of economic development as the creative class is more likely to be attracted to more highly developed areas, usually large cities. Furthermore, spillover effects from cultural activity promotes further development under the virtuous cycle. To investigate the relationship between CCI clusters and socio‐economic development, the locational data of municipal level CCI numbers is overlaid with a regional development indicator, a socio‐economic status index, which is based on census data and includes economic and social components. Results show that there is a general positive trend of CCIs locating in larger numbers (clustering) in areas with higher socio‐economic development performances.
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  • Date Issued: 2019

Customer loyalty programmes in the South African grocery and retail sector

  • Authors: Harmse, Nyree
  • Date: 2019
  • Subjects: Customer loyalty programs -- South Africa , Customer clubs -- South Africa Grocery trade -- South Africa Food industry and trade -- South Africa
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/39599 , vital:35331
  • Description: While there has been substantial research on loyalty programmes, few studies specifically focus on the attitudinal and behavioural components of a loyalty programmes within grocery and retail sector programmes in South Africa. This study is part of a broader study of South African loyalty programmes, but specifically examines the attitudinal and behavioural influences on loyalty programmes in the South African grocery and retail sector. A comprehensive literature review was conducted and factors influencing loyalty programmes were identified. The literature reviewed informed the conceptual model that proposed purchasing behaviour, trust, communication, personalisation, flexibility, rewards and method of participation influenced the success of grocery and retail sector loyalty programmes with attitude and behaviour serving as intermediate variables. The academic literature selected for the study is grounded in the academic theories of social exchange and planned behaviour. The methodology followed was through self-administered questionnaires developed from academic literature. Data were collected from 1090 respondents across South Africa, of which 643 respondents were members of grocery and retail sector loyalty programmes. The data analysis conducted through various descriptive and inferential statistical tests and exploratory factors analysis identified that factors of purchasing behaviour, trust, communication, personalisation, flexibility, rewards and general assessment were factors influencing loyalty programmes. Loyalty programme studies in South Africa are generally conducted on specific loyalty programmes, which are owned by the programme owners and therefore unpublished. This study contributes to the body of knowledge by using academic theory to establish the attitudinal and behavioural factors that affect loyalty programmes within the South African grocery and retail sector. The study concludes with managerial recommendations that grocery and retail sector managers can implement to influence the success of loyalty programmes. Some of the recommendations include the use of communication as a lever to influence other factors and the overall effectiveness of the programme. Other recommendations include data management and rewards that create flexible and personalised experiences.
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  • Date Issued: 2019

Damage recovery for robot controllers and simulators evolved using bootstrapped neuro-simulation

  • Authors: Leonard, Brydon Andrew
  • Date: 2019
  • Subjects: Robots -- Control systems , Robots -- Programming Robotics Neural networks (Computer science)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/40424 , vital:36164
  • Description: Robots are becoming increasingly complex. This has made manually designing the software responsible for controlling these robots (controllers) challenging, leading to the creation of the field of evolutionary robotics (ER). The ER approach aims to automatically evolve robot controllers and morphologies by utilising concepts from biological evolution. ER techniques use evolutionary algorithms (EA) to evolve populations of controllers - a process that requires the evaluation of a large number of controllers. Performing these evaluations on a real-world robot is both infeasibly time-consuming and poses the risk of damage to the robot. Simulators present a solution to the issue by allowing the evaluation of controllers to take place on a virtual robot. Traditional methods of controller evolution in simulation encounter two major issues. Firstly, physics simulators are complex to create and are often very computationally expensive. Secondly, the reality gap is encountered when controllers are evolved in simulators that are unable to simulate the real world well enough due to implications or small inaccuracies in the simulation, which together cause controllers in the simulation to be unable to transfer effectively to reality. Bootstrapped Neuro-Simulation (BNS) is an ER algorithm that aims to address the issues inherent with the use of simulators. The algorithm concurrently creates a simulator and evolves a population of controllers. The process starts with an initially random population of controllers and an untrained simulator neural network (SNN), a type of robot simulator which utilises artificial neural networks (ANNs) to simulate a robot's behaviour. Controllers are then continually selected for evaluation in the real world, and the data from these real-world evaluations is used to train the controller-evaluation SNN. BNS is a relatively new algorithm that has not yet been explored in depth. An investigation was, therefore, conducted into BNS's ability to evolve closed-loop controllers. BNS was successful in evolving such controllers, and various adaptations to the algorithm were investigated for their ability to improve the evolution of closed-loop controllers. In addition, the factors which had the greatest impact on BNS's effectiveness were reported upon. Damage recovery is an area that has been the focus of a great deal of research. This is because the progression of the field of robotics means that robots no longer operate only in the safe environments that they once did. Robots are now put to use in areas as inaccessible as the surface of Mars, where repairs by a human are impossible. Various methods of damage recovery have previously been proposed and evaluated, but none focused on BNS as a method of damage recovery. In this research, it was hypothesised that BNS's constantly learning nature would allow it to recover from damage, as it would continue to use new information about the state of the real robot to evolve new controllers capable of functioning in the damaged robot. BNS was found to possess the hypothesised damage recovery ability. The algorithm's evaluation was carried out through the evolution of controllers for simple navigation and light-following tasks for a wheeled robot, as well as a locomotion task for a complex legged robot. Various adaptations to the algorithm were then evaluated through extensive parameter investigations in simulation, showing varying levels of effectiveness. These results were further confirmed through evaluation of the adaptations and effective parameter values in real-world evaluations on a real robot. Both a simple and more complex robot morphology were investigated.
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  • Date Issued: 2019

Deconstructing “the South African jazz feel”: roots, rhythms and features of South African jazz

  • Authors: Thorpe, Christopher John
  • Date: 2019
  • Subjects: Jazz -- History and criticism , Jazz -- African influences , Jazz -- Africa --History and criticism , Jazz -- South Africa --History and criticism
  • Language: English
  • Type: text , Thesis , Masters , MMus
  • Identifier: http://hdl.handle.net/10962/76649 , vital:30612
  • Description: South African jazz has established itself as a distinct and influential genre in modern popular music that merges musical elements from traditional South African musics with influences from U.S.-American jazz. Formed during a time of extreme social inequality in a divided country, South African jazz became the soundtrack of the struggle against social injustice and racial oppression, and was brought to international attention by artists such as Hugh Masekela, Miriam Makeba, and Abdullah Ibrahim who gave poignant musical expression to the hardships of the time. South African jazz is celebrated for its unique sound, original catalogue and all-important “feel”. To many listeners, performers and musicologists, it is this concept of feel that makes South African jazz so distinctive and inimitable. To date, however, much of the scholarly and popular literature on South African jazz has centred on the historical, social and political aspects of the music, with less attention given to close musical-textual analysis. A few studies have considered the melodic and harmonic language of iconic saxophonists and bass players but there are – to date – no close studies of rhythm and feel in South African jazz. Beginning to address this gap in the literature, this study uncovers some of the elements that constitute the South African jazz feel through close rhythmic and more general musical analyses of a selection of South African jazz recordings.
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  • Date Issued: 2019

Design and Characterization of a 5 kw Xe-Lamp Solar Simulator

  • Authors: Nwodo, Julian Chizoba
  • Date: 2019
  • Subjects: Solar energy
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10353/14671 , vital:40042
  • Description: The design and characterisation of a 5kW Xenon lamp solar simulator is presented. This was accomplished through considering the design features of an ellipsoidal reflector, Xe lamp characteristics and casing, and power supply; assembly of an ellipsoidal, Xe-lamp simulator; design and building of an automated control system capable of remotely controlling the operating mode of the simulator; establishing the 3 scenarios that must be met to conform to a AAA class simulator; characterization of the simulator in terms of temporal stability, irradiance uniformity and spectral match; and application of the simulator and comparing it with STC rated values. The considerations for the type of material used for housing the components of the solar simulator were made. A 5kW DC power supply and igniter for the Xe-lamp was carefully selected since they provide necessary power for running the simulator. The simulator has the ability to be used in either horizontal or vertical position by adjusting the reflector. An automated control system capable of remotely controlling the operating mode of the simulator was built for this study, this system enables the simulator to be operated in either auto or manual modes. It also incorporates an irradiance, temperature, current and voltage feedback. The characterisation of the solar simulator was over a 2.1 m X 1.6 m test plane. The area under which the characterisation was carried out within the test plane is 110 cm x 129.5 cm. At the end of the steady state large area solar simulator characterisation, a class A spectral match, class A spatial uniformity, and a class B temporal instability was obtained
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  • Date Issued: 2019

Determinants of a competitive bunkering service: a South African model

  • Authors: Mdlalose, Silindile
  • Date: 2019
  • Subjects: Ships -- Fuel -- South Africa , Oil transfer operations -- South Africa Coastal water transportation -- Economic aspects -- South Africa
  • Language: English
  • Type: Thesis , Masters , MBA
  • Identifier: http://hdl.handle.net/10948/41471 , vital:36487
  • Description: South Africa is one of the best strategically positioned countries in the world in terms of trade routes from the west to the east. According to the Operation Phakisa research team, about 13 000 vessels visit South African ports annually and nearly 30 000 vessels sail along the South African coast yearly. Yet, less than ten percent of visiting vessels replenish bunkers in the country. This is a lost business opportunity for the South African bunker industry. South Africa has struggled to attract and maintain bunker business for some time. The aim of this study is to establish what the determinants of a competitive bunker industry are. A positivism philosophy is adopted to conduct the study. Using information gathered through a literature review, a conceptualised model for a competitive bunker industry is formulated. The model claims that there is a positive relationship between bunker industry competitiveness and eight independent variables identified in literature. The eight independent variables identified are (i) Bunker Fuel, (ii) Location, (iii) Port Accessibility, (iv) Rules and Regulations, (v) Service, (vi) Infrastructure, (vii) Cost of Service and (viii) Human Capital. A survey is conducted using a questionnaire. The questionnaire was generated specifically to collect primary data. There are 104 usable responses received back from the survey. The response data are used for quantitative data analysis. Quantitative data analysis methods like the EFA, Cronbach’s alpha, one sample t-test and Pearson Moment Correlations’ analysis are employed to test the conceptualised model. Findings show that independent variables (i) Service, (ii) Infrastructure, (iii) Port Accessibility, (iv) Location and (v) Bunker Industry Competitiveness (the independent variable) are contributors to bunker industry competitiveness (dependent variable). The results indicate that to achieve bunker industry competitiveness, the best approach will be to employ a collective approach that will simultaneously consider all of the literature-identified variables. All of the variables will have to be considered and aligned when the strategy for a competitive bunker industry is created.
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  • Date Issued: 2019

Determinants of consumerisation of information technology and its effect on employee performance

  • Authors: Khayundi, Hilda
  • Date: 2019
  • Subjects: Information technology -- Economic aspect Organizational effectiveness
  • Language: English
  • Type: Thesis , Masters , MCom (Business Management)
  • Identifier: http://hdl.handle.net/10353/16906 , vital:40784
  • Description: The ubiquitous nature of personally technological advanced devices and applications has engendered various predictions for the current employee at the workplace. With the introduction and adoption of mobile phones, tablets, laptops and even software, organisations are gradually allowing employees to utilise their personal mobile devices at the office to accomplish their tasks. This has led to the term Consumerisation of Information Technology (CIT) or IT consumerisation. The purpose of this study was to investigate the determinants of consumerisation of IT and its effect on job performance of staff at an institution of higher learning. This study used a theoretical framework - The Unified Theory of Acceptance and Usage of Technology – to find out if indeed consumerisation of IT has an effect on job performance. An online questionnaire was sent to the university’s staff email and a total of 230 responses were recorded. The study used a quantitative research approach. The Statistical Package for Social Sciences (SPSS) software was used for data analysis to test the hypotheses. Tests such as the multiple linear regression, factor analysis, correlations, ANOVA and t-tests were used to test the hypotheses. The findings of the study showed that there is a relationship between the determinants of consumerisation of IT and their effect on job performance at the workplace. These determinants are performance expectancy, social influence and facilitating conditions. Effort expectancy was the only factor that did not have an effect on consumerisation of IT. As such the study suggested that institutions and organisations to take note of the technological development of devices that can help employees improve their productivity. However, this should be treated with caution as there are also negative effects such as technostress and cyberloafing which may be associated with the advent of consumerisation of IT, therefore it should be a gradual process in order to see the benefits.
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  • Date Issued: 2019

Determination of social, environmental and economic benefits for community participation in forestry in Mpumalanga, South Africa

  • Authors: Long, Leo Searle , Chirwa, Paxie
  • Date: 2019
  • Subjects: Forests and forestry -- South Africa -- Mpumalanga
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/34339 , vital:33307
  • Description: Rural communities living adjacent to commercial forestry operations are often affected by numerous negative social issues such as poverty, unemployment, poor healthcare, and limited infrastructure, amongst others. In excess of 61% of forestry land managed by the state owned SAFCOL SOC Ltd is under land claim, as part of the Restitution of Land Rights Act (Act 22 of 1994). It is therefore necessary for forest companies to seek active means of engaging and partnering with these communities through a participatory forest management (PFM) approach. This study explored the sustainable (social, environmental and economic), benefits of such an approach as perceived (experienced) by these local rural communities, and specifically land claimants. The study was conducted in communities adjacent to SAFCOL plantations in the Mpumalanga Province of South Africa. Data were collected between May and June 2017 by means of a structured questionnaire. Surveys were conducted on 46 households within the identified communities so as to verify and evaluate perceived benefits in terms of forest products, ecosystem services and amenities/services/infrastructure provided by SAFCOL and the broader forest industry. The results indicated that these communities recognize and obtain numerous social, environmental and economic benefits from the forest including Non-Timber Forest Products (NTFPs) such as firewood; forest provisioning ecosystem services (FPESs) such as improved water quality; and more metaphysical benefits such as access to gravesites and the protection of traditions and customs. These benefits have the ability to improve the social well-being, economic independence, and the quality of environmental services obtained by the associated communities. It was however found that the utilization of these benefits was widely differentiated according to gender and land claimant status. Whilst males and females largely benefitted equally, there was a distinct benefit preference between genders for different NTFPs. For example males showed preference for the collection of building material, bush meat and for livestock husbandry, whilst females showed preference for the collection of firewood, medicinal plants and fruit, amongst others. Similarly, it was found that overall, non-land claimants benefited more than land claimants. Reasons for this are primarily due to the increased distance with which the land claimants live from the forest resource when compared to non-land claimants. The empirical value of the data produced through this study will be invaluable in negotiations with the land claimant communities on land settlement agreements, joint venture proposals, including Participatory Forest Management, and future land tenure. Through such inclusivity and vested interest in the sustainable management of the forests, corporate risk is reduced and community/land claimant relationships are reinforced. Such Participatory Forest Management arrangements are key to ensuring the longevity and resilience to the forest sector post-transfer of claimed land.
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  • Date Issued: 2019

Determining the effects of debt-to-GDP ratio on the economic growth of Greece, Italy and South Africa

  • Authors: Mowoe, Merioboroghene Oreoluwa
  • Date: 2019
  • Subjects: Debts, Public -- Greece , Debts, Public -- Italy Debts, Public -- South Africa Economic development Greece -- Economic conditions Italy -- Economic conditions South Africa -- Economic conditions
  • Language: English
  • Type: Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10948/41942 , vital:36611
  • Description: A major challenge that most countries currently face, is to bring their economies out of indebtedness. In this study, the impact of public debt on the economic growth of Greece, Italy, and South Africa, and any similarities between them, was analysed. Two models were adopted for this purpose, the ARDL model and the VEC model. The ARDL was used to conduct a co-integration relationship between public debts, economic growth, with four controlled variables: inflation, government spending, net export, and investment. The results showed a negative co-integrating relationship for all three countries. In addition, the VEC model was adopted to determine whether there was causation between public debt and economic growth in each of the three countries. It was found that a unidirectional causality between public debt and economic growth exists for all three countries. For Greece, a long-run causality was found moving from economic growth to public debt. For Italy, short-run and long-run causalities were found, moving from economic growth to public debt. For South Africa, both a long-run and a short-run causality were found moving from public debt to economic growth. The economic growth and development policies for reducing the public debt of these countries, are recommended in accordance with the findings of the research results.
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  • Date Issued: 2019

Determining the hydrological functioning of the palmiet wetlands in the Eastern and Western Cape South Africa

  • Authors: Smith, Caitlin
  • Date: 2019
  • Subjects: Wetlands -- South Africa -- Eastern Cape , Wetland ecology -- South Africa -- Eastern Cape , Wetland management -- South Africa -- Eastern Cape , Prioniaceae -- South Africa -- Eastern Cape , Prionium serratum -- South Africa -- Eastern Cape
  • Language: English
  • Type: text , Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/95956 , vital:31218
  • Description: Wetlands provide a range of supporting, regulating and provisioning ecosystem services, including hydrological benefits such as flood attenuation and sustaining base flows. Despite their value, wetlands are one of the most vulnerable ecosystems in South Africa. Palmiet wetlands in the Eastern and Western Cape are particularly threatened. Palmiet (Prionium serratum) is a robust perennial plant that is endemic to wetlands and rivers located in the sandstones and quartzites of the Table Mountain Group (TMG), in the Eastern and Western Cape as well as the Natal Group sandstones in KwaZulu-Natal. Palmiet is described as an ecosystem engineer because of its ability to alter its environment and create large valley-bottom wetlands. The Krom River is an important water source for the city of Port Elizabeth and there has been a decline in palmiet wetlands along the Krom River as a result of alien vegetation invasion, agricultural activity, and gully erosion. Working for Water has been clearing alien vegetation and Working for Wetlands has been installing rehabilitation structures in the Krom River catchment for a number of years. There are, however, serious knowledge gaps in the understanding of palmiet wetland structure and function, particularly in respect of the hydrological functioning of these wetland systems. The aim of this study was to investigate the hydrology (surface and groundwater) behind these wetland systems. The investigation focussed on small-scale dynamics of the palmiet wetland system in order to increase general understanding of the surface water and groundwater processes of these wetland systems. Field work was concentrated on the Kompanjiesdrif and Krugersland palmiet wetlands in the upper K90A Krom River catchment. The investigation involved the installation of piezometers, water quality and stable isotope sampling and analysis, an Electrical Resistivity Tomography survey, and hydrological and mixing cell modelling. The results of the investigation indicate that the hydrological functioning of palmiet wetlands is closely linked with high sub-surface discharges typically associated with TMG aquifers. It is proposed that the palmiet wetlands are sustained by significant amounts of sub-surface water (both groundwater and interflow) moving through preferential flow paths in the alluvial fans and tributaries, which are in turn sustained by groundwater discharge from the surrounding sandstones and quartzites of the Nardouw Sub-group and Peninsula Formation. The palmiet wetlands clearly retain a significant amount of water, leading to the maintenance of prolonged flows, and a larger baseflow. However, it is hypothesised that the occurrence of palmiet as the dominant species in these wetlands is due to the sustained low flows related to catchment geology and high hydrological connectivity between the catchment and the wetland that is enabled by flow paths that allow the free flow of water from the catchment to the wetland. It is further proposed that palmiet is possibly more reliant on a consistent water supply for its existence and survival than it is on acidic nutrient-poor water and soils as stated by other authors.
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  • Date Issued: 2019

Developing ocean particle tracking tools for cross-disciplinary oceanic research with applications in the Agulhas current region

  • Authors: Hart-Davis, Michael Geofrey , Backeberg, Björn C
  • Date: 2019
  • Subjects: Ocean currents , Ocean currents -- Measurement Oceanography Oceanography -- Research -- South Atlantic Ocean
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/42308 , vital:36644
  • Description: Lagrangian ocean analysis is a powerful way to study ocean processes from in-situ observations and numerical model simulations. As numerical modelling capabilities develop and physical mechanisms of the ocean are better understood, the importance of particle trajectory modelling continues to increase. Therefore, developing cross-disciplinary particle trajectory model applications for the Greater Agulhas System is highly relevant due to its potential contribution to scientific studies and operational applications. This thesis presents the results of developing particle trajectory model applications in the Greater Agulhas System towards better understanding the physical mechanisms that drive ocean processes in the region. The model is used in three applications that demonstrate their cross-disciplinary potential. These applications include a search and rescue scenario, the study of ocean dynamics and the study of the fate of juvenile turtles. Introducing spatially and temporally varying stochastic motion to account for the processes not resolved in the ocean surface current products, as well as including more appropriate boundary conditions, were shown to improve the accuracy of virtual drifters in representing the trajectory of a real surface drifter. Next, implementing the spatially and temporally varying stochastic motion in the particle trajectory model and applying it to a search and rescue scenario of a capsized catamaran revealed that including both winds and surface ocean currents in the particle trajectory model allowed for an improved prediction of the capsized vessel’s trajectory. By comparing a pair of real surface drifters with the particle trajectory model and analysing high resolution sea surface temperature (SST) fields it was shown that the formation of an eddy on the Agulhas Plateau combined with the weakening of the core current velocity resulted in enhanced eddycurrent interactions facilitating the separation of the real surface drifter-pair as they passed through this region. Lastly, the particle trajectory model was used to study the importance of including active swimming characteristic when studying the fate of juvenile turtles. It was found that including active swimming resulted in a change in the distribution of juvenile turtles and, therefore, needs to be included to provide a proper understanding of the fate of juvenile turtles in the ocean. With further development and refinement of the particle trajectory model, Lagrangian ocean analysis has the potential to provide valuable information towards improving our understanding of physical and biological ocean processes at a range of spatial and temporal scales with potential operational oceanography applications.
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  • Date Issued: 2019

Development and characterisation of miconazole nitrate loaded solid lipid nanoparticles for incorporation into a vaginal mucoadhesive system

  • Authors: Gwimo, Wimana Alexis
  • Date: 2019
  • Subjects: Vaginitis , Vagina -- Diseases Sexually transmitted diseases -- Diagnosis Sexually transmitted diseases -- Treatment
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/39632 , vital:35335
  • Description: Vulvovaginal candidiasis (VVC) is the second most common cause of vaginitis, affecting 75% of women of sexual maturity. The prescribed first line treatment involves the use of locally-acting imidazole creams. These conventional dosage forms possess limitations, such as leakage, messiness and low residence time at the site of application; all which promote poor patient adherence to pharmacotherapy. Poor adherence is then attributed to increased incidence of VVC reoccurrence and the emergence of Candida strains. It was, therefore, speculated that through the use of novel drug delivery systems (NDDS), the pharmacokinetic and antimicrobial characteristics of a model antifungal drug (miconazole nitrate [MNZ]) could be improved. Primary aim: To develop, optimise and characterise a mucoadhesive hydrogel incorporated with MNZ loaded solid lipid nanoparticles (MNZ-SLNs) for the intended treatment of VVC. This study was conducted in three phases, viz. pre-formulation studies, development, optimisation and characterisation of MNZ-SLNs, and the development and characterisation of MNZ-SLN-loaded thermoresponsive hydrogel. An alternative method for the quantification of MNZ was developed through the use of an octyl stationary phase. The method was deemed suitable for its intended use with a linear equation of y = 811214x + 67958 and a respective limit of quantitation (LoQ) and detection of 0.015 mg/ml and 0.052 mg/ml. Differential scanning calorimetry (DSC) studies suggested that cholesterol showed great promise of facilitating high drug entrapment efficiency (EE). MNZ-SLNs were prepared by means of a novel melt- emulsification sonication and low temperature solidification method and optimised statistically by a 13-run-two-factor central composite rotatable design (CCRD). The predicted optimisation parameters were 4% m/v lipid concentration and 260.94 sonication time. Optimal MNZ-SLN formulations were prepared and characterised by means of photon correlation spectroscopy (PCS), transmission electron microscopy (TEM) and centrifugation. PCS revealed uniform particles with a narrow polydispersity index (PDI) and a mean hydrodynamic diameter (z-avg.) of 73.03 nm and zeta potential (ZP) of 38.43 mV. Percent EE was calculated via an indirect method as 75.24%. Furthermore, the MNZ -SLNs were incorporated into a mucoadhesive thermo-responsive hydrogel with a sol-gel transition temperature of 33.33 ± 2.82 °C. In vitro drug release testing (IVDRT) was undertaken with the aid of a Franz diffusion vertical cell (FDVC) apparatus. A % cumulative drug release of 27.94% and 15.87% was obtained for MNZ- SLNs and MNZ-SLN hydrogels, respectively, after eight hours. The resultant data was fitted into various kinetic models with the aid of DDSolverTM (Microsoft Excel® add-ins, 2016) to evaluate which model attained the highest correlation co-efficient (r2). Both formulations attained high r2 of 0.9941 and 0.9945, respectively, with the Korsmeyer- Peppas mathematical model. A high diffusional exponent (n) of >1 was observed, suggesting a super case II drug release mechanism. Finally, a modified Kirby-Bauer disc diffusion assay was used for ascertaining Candida albicans susceptibility to the developed formulations. Controls in the form of unloaded preparations and a commercially available cream were used. MNZ-SLNs and MNZ-hydrogel demonstrated superior antifungal activity to the commercially available cream. These results indicate that the developed MNZ-SLNloaded hydrogel formulation with localised thermo-responsive effect may be a promising carrier for intravaginal delivery of MNZ in the treatment of VVC.
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  • Date Issued: 2019

Development of a framework for a proposed antimicrobial usage reporting tool for public sector hospitals

  • Authors: Ramjan, Yumna
  • Date: 2019
  • Subjects: Anti-infective agents
  • Language: English
  • Type: Thesis , Masters , MPharm
  • Identifier: http://hdl.handle.net/10948/43030 , vital:36727
  • Description: Background: The inappropriate and unnecessary use of antimicrobials has increased the need to monitor antimicrobial usage so as to identify inappropriate use. In order to support the antimicrobial stewardship (AMS) programme, it is important to quantify the usage of antimicrobials and this can be achieved by promoting the use of AMS utilisation metrics. They are used to measure the progress and efficacy of an AMS programme (Brotherton, 2018).Primary Aim of Research: The primary aim of the research was to develop a framework for a proposed antimicrobial usage reporting tool, which would integrate with various data sources in order to be used by AMS practitioners to optimise antimicrobial usage in the South African public sector hospital setting.Methodology: The study was divided into three phases: a preliminary phase, a developmental phase and a post-developmental phase. The preliminary phase focused on obtaining a comprehensive understanding of the type and nature of the AMS utilisation metrics and subsequently identifying the views on the usage, usefulness and clinical relevance of those AMS utilisation metrics using a quantitative questionnaire, which was conducted among infectious disease specialists, pharmacists, medical prescribers, i.e. prescribers who were not specialists and clinical pathologists employed at tertiary level, public sector hospitals in the Eastern Cape province of South Africa. Consequently, a qualitative semi-structured interview was conducted among healthcare professionals who were involved in the daily implementation of AMS in the workplace. Results obtained from the quantitative component and qualitative component were integrated in order to develop a framework for a proposed antimicrobial usage reporting tool. Results: The Defined Daily Dose (DDD), Prescribed Daily Dose (PDD) and Days of Therapy (DOT) were identified as the most common AMS metrics (Grau et al., 2013). However, the DDD was the only AMS metric currently recommended by the South African National Department of Health (South African National Department of Health, 2017a)and it was the only AMS metric currently being utilised at two of the five research sites in the Eastern Cape province of South Africa. It was identified that data pertaining to antimicrobial usage was available and was being extracted from Rx Solution®. However, the programme did not have the ability of automatically producing the reports, hence, emphasising on the need for an antimicrobial usage reporting tool for South African public sector hospitals. Therefore, the framework for the proposed antimicrobial usage reporting tool would integrate antimicrobial stock management data with the following AMS utilisation metrics: DDD, DOT and PDD, were considered for inclusion in the proposed antimicrobial usage reporting tool. Conclusion: The qualitative findings obtained during the post-developmental phase, therefore, established that although an electronic platform for the purpose of monitoring antimicrobial usage for the South African public sector hospitals was required, there would be many challenges obstructing the implementation of the proposed antimicrobial usage reporting tool.
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  • Date Issued: 2019

Development of a manual to train food handlers of the national school nutrition programme

  • Authors: Barkhuizen, Kirsten Lyn
  • Date: 2019
  • Subjects: Food -- Safety measures
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/36559 , vital:33974
  • Description: The study was conducted in order to develop a hygiene and food safety manual that can be used to train the food handlers of the National School Nutrition Programme. The co-operation of the Institute for International Medicine, Partnerships with Children, as part of the Health in Action Programme in this study, is appreciated. Food handlers of the National School Nutrition Programme in low socio-economic schools, in the Nelson Mandela Bay, in the Eastern Cape, were the population of the study. With many South Africans experiencing poverty and food insecurity, the National School Nutrition Programme aims to provide a social safety net and address short term hunger in children. However, challenges are faced regarding the implementation thereof, such as a lack of training of food handlers. This results in poor hygiene and food safety knowledge and behaviour. Subsequently, the risk of transmission of foodborne pathogens and the contamination of food rises. Foodborne illnesses are a major cause of morbidity and mortality, specifically in children, due to weak immune systems. Therefore, the study was conducted in order to develop and test a hygiene and food safety manual so that it can be made available to the South African Department of Education to be used by teachers in order to train the food handlers of the National School Nutrition Programme. The manual can then be used to train all newly recruited food handlers, and therefore ensure that school meals are safe to consume by learners.
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  • Date Issued: 2019

Development of a nystatin-loaded micellar system for oral mucoadhesion

  • Authors: Sarpong, Nancy Owusu Akyere
  • Date: 2019
  • Subjects: Medical microbiology , HIV infections -- Treatment Clinical pharmacology
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/43556 , vital:36918
  • Description: Oropharyngeal Candidiasis (OPC) is an opportunistic fungal infection that affects mostly infants and immunocompromised patients. In recent years, the disease has been on the rise due to an increased life span, the HIV pandemic and the increased use of broad spectrum antibiotics. OPC may be treated using a nystatin suspension, which is not as effective as it could be due to the mechanism by which the suspension is applied to the affected tissue. This research aims to improve the effectiveness of nystatin, for the treatment of OPC, by proposing a nystatin loaded micellar system incorporated into a mucoadhesive system for drug delivery. This will ensure that nystatin is gradually released from the film, thus increasing retention time of nystatin at the affected area. In this study, a mixture design was developed, which was used to determine the most appropriate solvent system for nystatin solubilization. Optimisation of the micelle formulation was achieved by using the central composite rational design (CCRD). The two factors that were taken into consideration were the temperature of the hydration medium (water) and the length of time the micellar solution was exposed to the temperature environment of the rotary evaporator. The responses that were investigated were the mean particle size, mean polydispersity index (PDI), mean zeta potential, change in mean particle size and change in mean PDI. The optimal micelle formulation was characterised for size, stability, morphology and drug encapsulation efficiency. The micelles were found to be spherical and stable with an acceptable size range. However, their drug encapsulation efficiency was low. The mucoadhesive film was formulated and characterised for physical characteristics, pliability, percentage swelling index and drug release profile. The film was found to be highly pliable and evenly distributed with a smooth surface; no bumps or bubbles were visible. The film was able to swell to up to 550 %. In vitro studies showed that nystatin was gradually released from the film.
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  • Date Issued: 2019

Development of an Extensible Framework for Easy Implementation of Image Processing Applications on Android Operating System

  • Authors: Gunu, Bulelani
  • Date: 2019
  • Subjects: Operating systems (Computers)
  • Language: English
  • Type: Thesis , Masters , MSc (Computer Science )
  • Identifier: http://hdl.handle.net/10353/17201 , vital:40865
  • Description: Image processing is a field that has been in existence for many years and it continues to grow with many other research areas adopting its use. One such research area is the area of mobile devices. Mobile devices have been equipped with image processing software and hardware so as to apply image processing features. While there are many applications of image processing and new applications have been developed, there are still many functionalities that these image processing software perform the same. The development of these software from scratch requires a lot of effort and can be time consuming. This becomes even worse for mobile device application developers, specifically Android developers, who have no knowledge of implementing image processing functionalities. This project offers a software framework which allows Android application developers to focus on their unique requirements while incorporating image processing features into their applications. The framework provides the common image processing functionalities and Android developers do not need to know the internal working of the framework in order to use it. This helps reduce application development time and effort. The framework also offers an extensibility feature which takes into consideration the future growth. This means that third party developers can keep the framework up to date with the technological advancements. The presented framework is shown to be requiring less technical expertise. Also, the way in which the system is design makes it easy to understand. This design can be adopted for other related projects that require extensible frameworks for the Android operating system.
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  • Date Issued: 2019

Development of polypropylene – waste tyre crumbs based tpe's with the aid of vistamaxxtm as a compatibiliser

  • Authors: Masele, Siyamtanda
  • Date: 2019
  • Subjects: Polymers , Polymerization Crumb rubber Rubber
  • Language: English
  • Type: Thesis , Masters , MTech
  • Identifier: http://hdl.handle.net/10948/42589 , vital:36670
  • Description: Polypropylene (PP) is a semi crystalline thermoplastic polymer and one of the most commonly used polyolefins. It is well known for its poor impact resistance; hence, for industries such as the automotive and packaging, reinforced PP is widely used. In general plastic waste disposal is a global crisis raising environmental and human health concerns, with PP being the highest consumed polymer globally; hence a push in the reuse and recycling of PP. Recycled polypropylene has limited uses for industrial applications due to its highly reduced properties owing to the recycling process which inhabits cutting of chains lengths, broadened molecular weight distributions and compromised crystallinity. Several studies have investigated the use of reinforcing fillers and modifiers in order to improve properties of PP. Inorganic materials and minerals such as CaCO3, Mica, Talc and glass fibre are used as fillers to improve mechanical properties (tensile and hardness), but still lacks in improving the impact resistance. Thermoplastic elastomers (TPE) are typically used where elastomer and thermoplastics fail as individual components. This is because they have the benefit of thermoplastic properties at hypo ambient condition and elastomer properties such as good impact and elongation at sub-zero conditions. The study took a route of using PP and waste tyre crumb rubber (CR) material to prepare potentially low-cost waste based TPE’s, which would then inherit both properties of PP and the rubber component. VistamaxxTM 6202 (EPR), a commercial name for ethylene-propylene monomer (EPR), was used as a compatibiliser to improve interaction between PP and CR and to contribute towards the overall improvement of various properties such as mechanical properties. VistamaxxTM has a low glass transition temperature (Tg, = -30 ºC), which is important for low temperature applications such as cold storage; it also has a very high elongation and as a result contributed significantly to the overall properties when used in TPE blends. The study highlighted differences between two TPE compounding formulation pathways; namely master-batch (MB) and design of experiments (DoE). The MB formulations were blends that were prepared by a conventional way of compounding; where a pre-mixed CR/EPR blend, in the ratio of 80(CR):20(EPR), was used to form a master-batch. Results showed that there are some similarities between TPEs prepared in different ways, which suggests that the ultimate properties such as thermal stability are in fact more PP matrix based. Thermal analyses results revealed that when high amount of CR was added to the TPE blends, there was a substantial amount of residue mainly due to inherent carbon black. The degree of crystallinity of the blends decreased with increased amounts of CR irrespective of whether it was the MB or DoE blends. The MB TPE blends demonstrated that hardness is not linked to the amount of the MB nor the crystallinity of blends. Meanwhile, tensile elongation and tensile stress were affected by crystallinity. On the other hand, the impact strength findings showed that the amount of MB in TPE blends reached a threshold at 30%. The DoE based TPE blends demonstrated that the optimum mechanical properties are observed when components of the blends are incorporated individually during compounding. This was observed for impact strength, tensile stress as well as elongation at break. The results showed that the incorporation of EPR should be at least 20% for good impact and elongation properties; however, for tensile and hardness, the PP matrix must be high. The study also showed that, for better mechanical properties it was more suitable to use the blends formulated with DoE, because the master-batch approach limited the improving of the mechanical properties by an addition of up to 30% of both the CR and EPR. The storage modulus as well as the tan delta for both MB and DoE decreased when the elastomeric phases were added on both methods, whereas tan delta Tg values decreased as more of the elastomeric phase was added. Evidence from morphology studies showed that the majority of TPE blends suffer from inadequate distribution and adhesion between PP and elastomer; resulting in poor mechanical properties. Furthermore, a threshold of matrix invasion is observed from 30% and above of CR in the blend, where lack of in capsulated lamps of CR were observed hindering the stress induced crystallization and relaxation of the PP phase. The latter was observed irrespective of the type of blend, which strongly suggests and highlights the limits of blending PP with elastomers. Study demonstrated the ability of VistamaxxTM to be utilized as a binding material for PP and CR and displaying the challenges that might arise when used as a master-batch with crumb rubber.
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  • Date Issued: 2019

Development of silver-based polyaniline nanocomposite for electrochemical oxidation and detection of organosulfur compounds

  • Authors: Shoba, Siyabonga
  • Date: 2019
  • Subjects: Polyethylene -- Analysis , Composite materials Nanocomposites (Materials)
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/43600 , vital:36928
  • Description: Human activities such as combustion of fossil fuels through automobiles, factories and electricity generation using coal results in major productions of sulfur dioxide to the atmosphere. The sulfur dioxide gas chemically reacts with other substances (i.e. water and oxygen) in the atmosphere and produces acidic pollutants. These acidic pollutants exist in both wet and dry form and before they are deposited on the earth’s surface, they can travel long distances carried by the wind. They are deposited in a wet form as rain, snow, fog and sleet and in a dry form as gases or particles. This has led to the mandated 10 ppm S in fuel by the environmental protection agency (EPA). Electrochemical desulfurization (ECDS) has been reported as an innovative technique for removing sulfur via redox processes. ECDS technique is a low costs process as no catalysts and oxidant are involved and it is a green technology (environmental benignity), thus making the process more economical than conventional hydrodesulfurization (HDS) technologies. Modification of electrodes for electrochemistry as well as electrodeposition of metal nanoparticles offers interesting electrochemical activities due to their reduced size and high surface area to volume ratio. Electrochemical oxidation of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) was analysed in acetonitrile using carbon electrodes modified with silver (Ag)-polyaniline (PAni) based nanocomposites (GCE/PAni/Ag and GCE/Ag). The PAni, PAni/Ag composites were characterized using spectroscopic (FT-IR, XRD, XPS) and microscopic (SEM and TEM) techniques. SEM confirmed that the synthesized PAni and PAni/Ag presented an amorphous granular morphology with the aggregation of small irregular particle sizes. Cyclic voltammetry of BT, DBT and 4,6-DMDBT on the modified glassy carbon (GCE) electrode show chemically irreversible anodic peaks which corresponds to electron transfer of sulfur to form sulfoxide and lastly sulfone containing compounds. The overall conversion yield of DBT and 4,6-DMDBT to respective sulfones increased as water content increases. Products were characterized by means of gas chromatograph coupled to mass spectrometer (GC-MS), 1H and 13C NMR. Similarly, silver-modified Glassy Carbon (GCE) electrode was used for the electrochemical detection of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (4,6-DMDBT) in the presence of naphthalene (NP) and carbazole (CR). The electrochemical response of BT, DBT and 4,6-DMDBT on the modified electrode was determined using Differential Pulse Voltammetry (DPV) in acetonitrile. The electrochemical behaviour of BT, DBT and 4,6-DMDBT showed that the modified electrode exhibited excellent oxidation electro-catalytic activity. The dynamic range for the organosulfur compounds determination was from 1 to 11 ppm with detection limits (LOD) of 0.60 ppmS, 0.41 ppmS and 0.21 ppmS for BT, DBT and 4,6-DMDBT, respectively. Electrochemical sensor showed excellent selectivity of the compounds in the presence of interfering compounds such as naphthalene, carbazole and thiourea over the studied range of concentrations. The prepared electrode exhibited satisfactory reusability and stability after four successive measurement. It has been demonstrated in this study that modified glassy carbon (GCE) electrode (GCE/PAni/Ag) can be successfully used for the assay of sulfur containing compounds such as BT, DBT and 4, 6-DMDBT in petroleum samples.
  • Full Text:
  • Date Issued: 2019

Devulcanisation of truck tyre tread vulcanisates in supercritical carbon dioxide using diphenyl disulphide and 2,2- dithiobis(benzothiazole)

  • Authors: Mabuto, Briswell , Ogunlanja, A
  • Date: 2019
  • Subjects: Vulcanization , Polymeric composites Rubber Carbon dioxide -- Thermal properties Environmental chemistry
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/40702 , vital:36224
  • Description: A lot of work has been done in the recycling industry in an effort to increase the amount of reclaimed rubber used in new tyre formulations. The major drawback has been inferior physical and mechanical properties of reclaimed/virgin rubber blends in comparison to the virgin rubber material. Deterioration in these properties has been identified to be a result of chain degradation during reclamation processes as well as presence of crosslinks in the final reclaim product. Devulcanisation techniques have gained precedence due to the relatively improved properties of devulcanised/virgin rubber blends. The concept of devulcanisation is to reverse vulcanisation, resulting in total or partial cleavage of crosslinks. In this way, chain degradation is minimised while crosslink scission is maximised, thereby resulting in good quality devulcanised rubber. However, due to the persistence of chain degradation and crosslinks during devulcanisation processes, a very limited number of reports have claimed success in achieving this goal. Therefore there is still the need to develop a devulcanisation method that ensures improved quality and productivity of devulcanised rubber. Typical truck tyre tread vulcanisates were used for optimisation of time, temperature, heating rate, pressure and amount of devulcanising agent while monitoring percentage devulcanisation in supercritical carbon dioxide medium. Optimisation of the devulcanisation conditions was done by employing a twolevel central composite design in the isothermal and non-isothermal heating stages. This was followed by a single factor analysis of devulcanisation conditions in the non-isothermal stage. The effect of the presence of carbon black was investigated by comparing the percentage devulcanisation of carbon black filled and unfilled samples. The results show that supercritical carbon dioxide is an effective medium of devulcanisation using diphenyl disulphide (DD) and 2,2-dithiobis(benzothiazole) (MBTS). The relatively higher degree of devulcanisation observed during the non-isothermal stage compared to the isothermal stage, led to a shift of focus to non-isothermal devulcanisation. Temperature and time were found to have a significant antagonistic effect on the percentage devulcanisation, while changes in pressure above critical point and mass of devulcanising agent showed no effect on percentage devulcanisation. The heating rate was determined by the set-point, of which 180 ℃ set-point temperature resulted in desirable degree of devulcanisation for both DD and MBTS. 76.18 ± 5.50 % devulcanisation in 5 minutes at 102 ℃ was observed for DD whilst 70.92 ± 4.10 % devulcanisation in 4 minutes at 97 ℃ was observed for MBTS. Changes in pressure above critical point and mass of devulcanising agent used in devulcanisation showed no significant effect in the percentage devulcanisation and so they were kept constant at 80 bars and 1.00 % v (of weight of rubber sample) devulcanisation agent, respectively. The presence of carbon black was found to have an effect on the degree of devulcanisation; 87.95 % and 81.33 % devulcanisation was observed for unfilled samples devulcanised using DD and MBTS respectively. Thermogravimetric analysis of the natural rubber/styrene butadiene rubber (NR/SBR respectively) relative composition of devulcanisates indicated uneven devulcanisation when using DD, whereas MBTS did not show any form of preference. DD showed preference for NR devulcanisation over SBR. Further analysis of the sol and gel fractions were performed using; Differential Scanning Calorimetry, Fourier Transform Infrared Spectroscopy, Gel Permeation Chromatography and Gas Chromatography coupled with Mass Spectroscopy. Application of the optimised conditions to devulcanise ground tyre rubber (GTR) resulted in relatively lower degrees of devulcanisation for both DD and MBTS; 41.22 ± 4.22 and 22.41 ± 1.97 respectively. The differences in the degree of devulcanisation of the laboratory prepared vulcanisates and the GTR was determined to be due to sample differences; i.e. sample constituents, particle dimensions and crosslink network (crosslink distribution in particular).
  • Full Text:
  • Date Issued: 2019
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