Characterization of the heat source of thermal aquifers within the Soutpansberg Basin in the Limpopo Province, South Africa: Evidence from geophysical and geological investigations
- Authors: Nyabeze, Peter Kushara
- Date: 2019
- Subjects: Basins (Geology) -- Analysis Geology, Structural -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD (Geology)
- Identifier: http://hdl.handle.net/10353/15167 , vital:40192
- Description: The research was conducted to contribute towards the knowledge base on the potential for geothermal energy in the Soutpansberg Basin, located in the Limpopo Province of South Africa. The focus area was Siloam, an area that hosts a hottest spring with the highest recorded temperature of 67.5°C. The research involved visits to the Soutpansberg Basin, water sampling, carrying out ground geophysical surveys, and high-level processing of airborne magnetic data to determine depths and temperatures of magnetic sources. The water samples from the hot springs were found to be enriched in sodium, bicarbonate and chlorine with very low concentrations of other element species. The chemical composition of the spring water indicated a source chemistry comprising of the Na-ClHCO3 water assemblage that is a typical signature for deep circulating groundwater of meteoric origin. The circulation depth was inferred to be 2.0 km. The increased resolution of the ground magnetic, electrical resistivity tomography, and electromagnetic conductivity methods data made it possible to delineate subsurface structures at the spring such as dykes, sills, faults and fractures from generated depth models. Modelling of ground magnetic data showed that the Siloam hot spring occurred between two interpreted north dipping dykes approximately 150 m apart. The minimum depth extent of the dykes was interpreted to be 650 m. The magnetic susceptibility values determined from rock measurements and modelling of magnetic data indicated the presence of volcanic and metamorphic rocks. Electromagnetic profiling data showed that there were three main high conductivity zones in the study area with values above 100 mS/m; A central zone associated with the spring; A zone to the south of the spring and a north zone associated with the Siloam Fault. Ground geophysics survey results confirmed the existence of the Siloam Fault. Two artesian boreholes with water warmer than 40 °C were identified to the south of the Siloam hot spring. Both electromagnetic conductivity and electrical resistivity tomography surveys delineated lateral and vertical variation in the bedrock to depths of 40 m to 60 m. Water bearing structures that could be faults, or fractures were identified. Layering due to weathering and water content was found to be in the depth range of 20 m to 40 m. The depths of the potential heat sources were computed from the radially averaged power spectrum of airborne magnetic data for square blocks with side dimensions L of 51 km, 103 km, and 129 km. Spectral analysis based approaches namely Centroid method, Spectral peak method, and the Fractal based approach were used for computing depth and temperatures to heat sources. Airborne magnetic data sets with larger window sizes were preferred for depth computations, as they preserved spectral signatures of deeper sources and reduced the contribution of shallower sources. The size of the data windows did not have a marked effect of depth and temperature values. Shallower magnetic sources depths of approximately 2.0 km were delineated using the Euler deconvolution method. An anticlinal feature at depths of 2.0 to 4.5 km was 4 Final Submission of Thesis, Dissertation or Research Report/Project, Conference or Exam Paper delineated in the central part of the basin. Spectral analysis results indicated that the depth to the top of magnetic sources was at 3.5 km to 6.2 km; the centroid of the basement at 7.92 km to 13.41 km, and the basal below 11.09 km and 14.08 km. The lower end depth spectrum was determined from application of the Centroid method with the deeper being results from the Fractal based approach. The Spectral peak method was useful for determining the depth to the top of magnetic sources. The temperature of the top of magnetic sources and basement centroid were computed to be in the range 234.00 °C to 281.34 °C. Magnetic source depths and basal temperatures that were in the Curie point range within which rocks lose magnetism due to heat were determined, using a computation approach that utilised fractal parameters, to be 21.39 km and 577.42 °C, respectively. Increasing the value of the fractal parameter β from 0 to 4, had an effect of retaining deeper depths and higher temperatures. The fractal parameter β range of 3 to 4 that gave the Curie point parameters indicated basal rock types with an igneous predisposition. The research highlighted evidence for the existence of the Soutpansberg Basin Geothermal Field (SBGF). The area around Siloam is a potential target for drilling exploration geothermal energy boreholes based on the occurrence of hot springs, shallow heat source depths, anticlinal structure, high formation temperatures, deep circulating water and the achieved Curie point temperature.
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- Date Issued: 2019
Data quality issues in electronic health records for large-scale databases
- Authors: Saiod, Abdul Kader
- Date: 2019
- Subjects: Electronic Health Records , Electronic Health Records--organization & administration Database management
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/44940 , vital:38190
- Description: Data Quality (DQ) in Electronic Health Records (EHRs) is one of the core functions that play a decisive role to improve the healthcare service quality. The DQ issues in EHRs are a noticeable trend to improve the introduction of an adaptive framework for interoperability and standards in Large-Scale Databases (LSDB) management systems. Therefore, large data communications are challenging in the traditional approaches to satisfy the needs of the consumers, as data is often not capture directly into the Database Management Systems (DBMS) in a seasonably enough fashion to enable their subsequent uses. In addition, large data plays a vital role in containing plenty of treasures for all the fields in the DBMS. EHRs technology provides portfolio management systems that allow HealthCare Organisations (HCOs) to deliver a higher quality of care to their patients than that which is possible with paper-based records. EHRs are in high demand for HCOs to run their daily services as increasing numbers of huge datasets occur every day. Efficient EHR systems reduce the data redundancy as well as the system application failure and increase the possibility to draw all necessary reports. However, one of the main challenges in developing efficient EHR systems is the inherent difficulty to coherently manage data from diverse heterogeneous sources. It is practically challenging to integrate diverse data into a global schema, which satisfies the need of users. The efficient management of HER systems using an existing DBMS present challenges because of incompatibility and sometimes inconsistency of data structures. As a result, no common methodological approach is currently in existence to effectively solve every data integration problem. The challenges of the DQ issue raised the need to find an efficient way to integrate large EHRs from diverse heterogeneous sources. To handle and align a large dataset efficiently, the hybrid algorithm method with the logical combination of Fuzzy-Ontology along with a large-scale EHRs analysis platform has shown the results in term of improved accuracy. This study investigated and addressed the raised DQ issues to interventions to overcome these barriers and challenges, including the provision of EHRs as they pertain to DQ and has combined features to search, extract, filter, clean and integrate data to ensure that users can coherently create new consistent data sets. The study researched the design of a hybrid method based on Fuzzy-Ontology with performed mathematical simulations based on the Markov Chain Probability Model. The similarity measurement based on dynamic Hungarian algorithm was followed by the Design Science Research (DSR) methodology, which will increase the quality of service over HCOs in adaptive frameworks.
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- Date Issued: 2019
Teachers’use of curriculum materials in Grade 3 Mathematics: A Case Study
- Authors: Whale, Susan Gaye
- Date: 2019
- Subjects: Mathematics -- Study and teaching (Primary) -- South Africa , Education -- curriculum innovation
- Language: English
- Type: Thesis , Doctoral , PHD
- Identifier: http://hdl.handle.net/10948/45591 , vital:38916
- Description: The study examines four curriculum documents with regards to curriculum facets, further interrogated through indicators for certain facets in order to ascertain whether the documents could be considered to be educative. Comparison is made with selected resources internationally. Observed episodes in four mathematics classes are interrogated with regards to teacher facets and concomitant indicators, to assess whether the tenets proposed in the written curriculum are translated into practice in the classrooms. The four Grade 3 teachers are interviewed about their views on the curriculum, their views on teaching and their views on their own agency in teaching mathematics. The teachers’ complete selected examples from a Mathematics Knowledge for Training (MKT) questionnaire and are engaged in conversations about iii their beliefs about mathematics and their confidence in both doing and teaching mathematics. The study identifies that the current CAPS curriculum documents focus on mathematical content almost exclusively and give minimal guidance concerning pedagogical content knowledge. The agency of teachers is not addressed. The study suggests a three-dimensional model of curriculum design that encompasses new educative curriculum materials; guidance on innovative teacher practices and direction towards new beliefs in teachers which could build agency and confidence. The concern that this study uncovers is that although the school and teachers were specifically chosen to minimise linguistic and social detractors, the intended curriculum does not appear to have been universally translated into
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- Date Issued: 2019
In-betweenness: a postcolonial exploration of sociocultural intergenerational learning through cattle as a medium of cultural expression in Mpembeni, KwaZulu-Natal
- Authors: Masuku, Lynette Sibongile
- Date: 2019
- Subjects: Postcolonialism , Environmental education -- South Africa , Community education -- South Africa -- KwaZulu Natal , Non-formal education -- South Africa -- KwaZulu Natal , Agricultural education -- South Africa -- KwaZulu Natal , Livestock -- Handling -- South Africa -- KwaZulu Natal , Cattle -- Handling -- South Africa -- KwaZulu Natal , Cattle herding -- South Africa -- KwaZulu Natal , Life skills -- Study and teaching -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/68181 , vital:29213
- Description: This case study was conducted in a small rural community called Mpembeni, in South Africa’s KwaZulu-Natal province. It was motivated by my observation of high levels of competence in ‘cattle knowledge’ amongst children coupled with a simultaneous failure at school. I view schools as integral parts of the community and consider them as being influenced by the community, which they in turn influence. This study set out to understand that which embodied informal learning in home/pasture-based contexts as well as formalised learning processes in schools. I used Sociocultural theory as the most congruent of educational theories to surface and illuminate the intergenerational learning processes that were taking place in the area. This warranted my use of research investigation methods that could, in non-intrusive ways, expose the everyday community practices that related to cattle as a particular medium of cultural expression. Ethnography, sourced from anthropology, aided by ethnomethods, was not only compatible with my study and the way in which I wanted to write out the research report, but also with my educational theory and its counterhegemonic intents. To understand the colonialities that framed the discord that embodied home and school as learning contexts, I used postcolonial theory, not only as a lens but as a counterhegemonic response. This theory also informed my research methodology as well as afforded me the reflexivity tools for an examination of my own intergenerational learning and the relational identities of myself as ‘Other’ in the lives of the research participants. It further facilitated the exploration of the potential for potential hybrid third spaces within the bubbling meeting nodes of the socio-cultural context of school and home/pasture based settings of learning. I observed cattle herding related practices, interviewed children, their parents and/or carers, dipping tank managers, livestock inspectors, community elders and members. I also analysed some of the written and unwritten content that made up the formal and informal based learning processes and reviewed some of the most recent South African Curriculum Statements and related texts on the representations of cattle. I sought views from teachers on their interactions with the people of Mpembeni, whose children they taught. I also explored axes of tension, silences and presences on anything related to cattle in schools. I argue and make a case for the development of thought by African scholars to advance Africa’s education rather than aid mimicry and the importation of theories of little congruence and relevance to the African context and Africa’s future. The study has made some contributions to new knowledge. This is in its exploration of sociocultural intergenerational methods and techniques that are employed for learning in community contexts, highlighting the importance of surfacing and understanding of children’s knowledge and experiences. The study has gone further to deliberate the in-betweenness of school and home learning environments, highlighting and unsilencing silenced, peripherised, new, old, considered irrelevant in the past, context and time congruent and liberatory knowledges. I propose that the knowledges located in these cleavages of difference be utilised to transform and create learning bridges between home and school environments. I propose that those ways of knowing that see others as nothings, be exposed and unlearned. Methods of learning that naturally unfold at home could be replicated at school with a recognition of the intergenerational methods, techniques, practices and the learning values in a critically constructive manner that narrows difference and othering.
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- Date Issued: 2019
Ecological assessment and biogeography of coastal vegetation and flora in southern Mozambique
- Authors: Massingue, Alice Obed
- Date: 2019
- Subjects: Coastal plants -- Mozambique , Coastal plants Marine biodiversity -- Mozambique Coastal biodiversity -- Mozambique
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/40988 , vital:36280
- Description: This study considered aspects of the vegetation of the coastal zone of southern Mozambique, an area with a rich biodiversity. The vegetation and flora were assessed in their current state including the associated anthropogenic pressures. The environmental conditions that determined the distribution of the vegetation were evaluated. A hierarchical classification, description and ecological interpretation of the vegetation and flora of the coastal zone in southern Mozambique are presented. Analysis was based on 242 sample quadrats that were distributed in a stratified manner throughout the study area. The vegetation could be grouped into six distinct types of vegetation: Dune Forest, Coastal Forest, Coastal Grassland, Coastal Miombo, Coastal Savanna and Coastal Woodland. Species diversity was high for the all the vegetation types, particularly in the woody elements. A total of 673 species in 410 genera was recorded. They represented 104 families with Fabaceae and Rubiaceae being the most common. Of these, 6.6% were endemic or near-endemic to the coastal zone of southern Mozambique with Coastal Forest being the habitat with the greatest endemism. All soils from different vegetation types had poor agricultural potential. Soil properties were the strongest defining environmental feature separating the vegetation types: e.g. pH was high in Dune Forest compared to the others. Results from Maxent modelling suggest that the distribution of endemic species is influenced by a combination of climatic and non-climatic variables. Soil type, temperature annual range and precipitation of the driest month were the most important predictor variables. Overlaying the potential distributions of the seven selected species indicated two areas of abundance of endemic species – these should be given attention for conservation. Endemic species are not well protected in southern Mozambique – their sampled and potential habitats are largely outside protected areas. Hence, additional reserves should be created to improve their protection. Most endemic and near-endemics species were found in the south, from Ponta de Ouro (Matutuine, south of Maputo Province) to Manhica district (north of the Maputo Province) forming part of the Maputaland Centre of Endemism. A second concentration of endemism was found in the Inhambane Province, specifically the Inhassoro and Vilanculos districts. This is proposed to be an Important Plants Area (IPA). Because most endemics and near-endemics are found in the Coastal Forest, their main threat is harvesting for charcoal production, although none of the endemic species are specifically targeted for charcoal production. In Inhambane they are also threatened by the tourism industry, agriculture and settlements. The impact of the habitat destruction on endemic species is expected to cause severe declines in the near future. The tourism industry and harvesting of trees for charcoal production and over-frequent fires are the main drivers of vegetation loss in this region. Shifting agriculture, harvesting for firewood and construction materials, cattle grazing (at a minor scale) are also impacts, but these were only observed in a small area of Maputo Province. Although the study was done in coastal zone of southern Mozambique, effective management of whole coastal zone of the country will be required to maintain a functioning and diverse ecosystem. Priorities for management are to ensure that forests are protected, in particular, Dune Forest. Actions are required to minimise degradation of coastal vegetation. Further research on Coastal Forest restoration should be planned, as field observations in this study confirm that forest in the coastal zone of southern Mozambique has resilience.
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- Date Issued: 2019
Catholic and charismatic: identity construction in a catholic charismatic movement in Nigeria
- Authors: Torty, Livinus
- Date: 2019
- Subjects: Catholic Church -- Nigeria , Pentecostalism -- Catholic Church Identity (Psychology) Identity (Psychology) -- Social aspects -- Nigeria
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/43787 , vital:37047
- Description: The Catholic Charismatic Renewal is a movement within the Catholic Church that blends and synthesizes elements of Catholicism and Pentecostalism. The movement straddles these two religious traditions within Christianity. Besides its incorporation of elements of Catholicism and Pentecostalism, the movement also has as its objective, the revitalizing and renewal of the Catholic Church through the power of the Holy Spirit. These fundamental orientations of the Catholic Charismatic Renewal distinguish it from other Catholic movements, bestowing on it its unique identity. Although different from other Catholic movements, the movement and its members lay claim to a Catholic identity and seek to assert its legitimacy within the Catholic Church. Existing literature has provided useful insights into the question of identity within the Catholic Charismatic Renewal. However, the question of identity construction within the movement has not been adequately and comprehensively addressed in academic literature. This is especially the case in the African context. This leaves therefore a gap in our knowledge of how the movement and its members construct their catholic and charismatic identities. This study sets out to explore how the movement and its members construct their identity in relation to the Holy Spirit, the institutional Catholic Church and other Catholics, as well as in the context of the movement’s ritual music. Identity construction in the Catholic Charismatic Renewal is seen as key to making meaning of the movement and its place within Catholicism. The study adopted a qualitative research and ethnographic approach in which empirical data was collected in the context of fieldwork through informal, semi-structured and focus group interviews as well as participant observation during the activities of a Catholic Charismatic prayer group in Minna, Nigeria. Theoretical perspectives drawn from identity, hermeneutics and anthropology of extraordinary experience were used as analytical lens in the study. The study revealed that identity within the Catholic Charismatic Renewal was constructed principally in relation to the Holy Spirit. A spiritual experience or encounter was central in such identity construction, and the subjective and intersubjective identity of the members revolved around the two key concepts of ‘spirit-centred identity’ and ‘empowerment’. The study indicated that the members of the movement constructed their identity in ways that demonstrated their loyalty to the Church and their status as an officially recognised Catholic movement. In addition, their identity was also constructed in relation to the functions that they perceived themselves to perform within the Catholic Church. Although the members of the movement considered their charismatic and catholic identities to be compatible, they understood themselves to be different from other Catholics. The study also showed that while music was considered to be important within the movement, the context and content of its ritual music were overwhelmingly Pentecostal, and music that projected a catholic identity was relegated to the background and given expression mainly in the realm of individual religious practice. The study suggests that identity construction within the Catholic Charismatic Renewal is multiple, ongoing, flexible, and sometimes contradictory and paradoxical. Through its identity construction, the members of the movement demonstrate the heterogeneity of the Catholic space and seek to extend the boundaries of Catholicism.
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- Date Issued: 2019
Perspectives on land and water politics at Mushandike Irrigation Scheme, Masvingo, Zimbabwe
- Authors: Mafukidze, Jonathan
- Date: 2019
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/76479 , vital:30573
- Description: Access to, control and ownership of land and water, amongst other natural resources in Zimbabwe, shape and affect rural lives, livelihoods, social relations and social organisation. Rural poverty has been entrenched and exacerbated by, amongst other factors, highly restricted access to these scarce resources. Historically, Zimbabwe’s rural areas (such as communal areas, smallholder irrigation schemes and resettlement areas) have existed as sites of struggles where contestations and negotiations over access to, control or ownership of these resources have taken place. Resultantly, multifaceted and dynamic social relations have been weaved and contested social spaces carved out. In rural Zimbabwe, contestations have tended to be complex, nuanced and intricate, working themselves out in different ways across time and space. In their heightened and more visible state, they have been characterised by violent physical expressions which, in the history of the country, involved two wars of liberation, the First Chimurenga (1896-1897) and the Second Chimurenga (1960s to 1980). The most recent violent manifestation was through nation-wide land invasions, politically christened the Third Chimurenga, which peaked in 2000 and continued sporadically to this day. Few studies on smallholder irrigation schemes in Zimbabwe have focused on understanding how contestations for access to scarce land and water resources are framed and negotiated at the local level. Cognisant of this lacuna, this thesis uses social constructionism in examining, as a case study, Mushandike Smallholder Irrigation Scheme in Masvingo Province in order to understand and analyse how land and water politics occur at the local level. The study deploys a qualitative research methodology approach in examining local water and land politics, which involved original irrigation beneficiaries and more recent land invaders. Findings of the thesis indicate that land and water shortages have increased considerably in the past two decades at the irrigation scheme due to the influx of land invaders into the scheme. This influx has had a negative impact on agricultural production and other livelihood strategies. Both scheme members and land invaders lay claim to land and water at Mushandike. These claims are intricately constructed and contested, and they are linked to broader issues such as partisan party-politics, policy developments, and tradition, origin, indigeneity and belonging. Though the struggles over land and water at Mushandike are firmly rooted in the concrete conditions of existence and experiences of beneficiaries and land invaders, external actors such as political leaders, state bureaucrats and traditional chiefs tend to complicate and intensify the contestations.
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- Date Issued: 2019
Intersectionality and complexity in the representation of ‘queer’ sexualities and genders in African women’s short fiction
- Authors: Du Preez, Jenny Boźena
- Date: 2019
- Subjects: Sexual minority culture , Sexual minorities' writings , African fiction -- Women authors -- History and criticism , Gender identity in literature , Short stories, South African , Feminism in literature , Political poetry , Eroticism in literature , Lesbianism in literature
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/119047 , vital:34697
- Description: This thesis sets out to contribute to the growing body of knowledge about queer sexualities and genders in Africa by examining their depiction in selected post-2000 African women’s short fiction written in English. Post-2000, the short story form has become the primary vehicle for queer representations by African women writers, and is thus an important development in the burgeoning body of queer literature by African writers. Broadly speaking, this literary formation can be defined as anti-homophobic, feminist and politically pragmatic. Using an intersectional lens, this thesis sets out to examine four significant strands in the political work these stories engage in. The chapters are structured around four main points of contention that have particular significance at the intersection of ‘queer’, ‘women’ and ‘Africa’. Firstly, I examine South African short stories that perform what I call queer conversations with history: imaginatively asserting a queer South African history, writing back against a male-dominated and heterosexist literary canon and, in doing so, contributing to the reimagination of the contemporary South African nation. Secondly, I analyse short stories from Africa that foreground the family, both as social formation and ideology. I examine how these stories ‘fracture’ this powerful and naturalised heterosexist concept by depicting the tensions and contradictions that queer characters experience in relation to family. Thirdly, I consider short stories from various African contexts that work to reconceptualise queer sexuality in relation to religious discourse in order to challenge homophobic and patriarchal religious authority. Finally, I examine queer, feminist erotic short stories by African women writers that challenges various colonialist, racist, sexist and lesbophobic discourses that have historically stifled the portrayal of sex and erotic experience between women.
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- Date Issued: 2019
Local web news as tools for framing food security: the content analysis of four selected Eastern Cape web newspapers
- Authors: Metula , Nolukhanyo Theorida
- Date: 2019
- Subjects: Food security World Wide Web
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/17484 , vital:41080
- Description: This study evaluates how the Eastern Cape local web newspapers frame food security in the Eastern Cape Province. A qualitative content analysis by means of textual analysis was used to evaluate the selected local web newspaper’s content on food security related stories within the period of July-December 2017. The sample was drawn from four Eastern Cape local web newspapers- Daily Dispatch Live, Herald Live, Go and Express and The Talk of the Town. The analysis sought to determine how the selected local web newspapers frame food security concerning food availability, accessibility and affordability in the Eastern Cape Province. Additionally, the study aimed to ascertain the issues about food security that are raised by the Eastern Cape local web newspapers and, to establish the extent to which these Eastern Cape local web newspapers’ framing is helpful in ensuring participation, empowerment and community mobilization for food securing purposes. The results of this study indicate that the local web newspapers frame Eastern Cape Province as untapped food basket. The framing suggests that the Province can leverage its agricultural resources for job creation which will ensure economic growth and food security. The local web newspapers framing suggests that there are numerous channels such as natural food production, livestock production, smallholder farming that can enhance availability and access to affordable food to people in the Eastern Cape Province. The findings revealed that local web newspapers frame increased agricultural production as an important issue that demand serious and urgent attention of the Provincial government as it has the potential of not only ensuring food security but also impacting positively on the income of local farmers. The local web newspapers frame farm attacks, land redistribution and reinstatement as important factors that hinder food production and, ultimately, food security in the Eastern Cape v Province. Furthermore, this study discovered that the frame of references used by the local web newspapers, especially the emphasis on local farming, land redistribution and private sector help to empower and mobilize individuals and communities to participate in food security initiatives. This study concludes that Eastern Cape Local Web Newspapers can be veritable tools to enhance food security channels in the Eastern Cape Province
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- Date Issued: 2019
A model for secure and usable passphrases for multilingual users
- Authors: Maoneke, Pardon Blessings
- Date: 2019
- Subjects: Computers -- Access control -- Passwords Computer security
- Language: English
- Type: Thesis , Doctoral , PhD (Information Systems)
- Identifier: http://hdl.handle.net/10353/12571 , vital:39289
- Description: Research on more than 100 million passwords that have been leaked to the public domain has uncovered various security limitations associated with user-generated short passwords. Long passwords (passphrases) are considered an alternative solution that could provide a balance between security and usability. However, the literature shows a lack of consistency in the security and usability contributions of passphrases. For example, studies that investigated passphrase security focusing on structural dependencies at character level found passphrases to be secure. Inversely, other research findings suggest that passphrase security could be compromised by the use of predictable grammatical rules, popular words in a natural language and keyboard patterns. This is further exacerbated by research on passphrases that is focused on the Global North. This is a huge concern given that results from inter-cultural studies suggest that local languages do influence password structure and to some extent, password usability and security. To address these gaps in the literature, this study used socio-technical theory which emphasised both the social and technical aspects of the phenomenon under study. Psychological studies show that the memory has limited capacity, something that threatens password usability; hence, the need to utilise information that is already known during password generation. Socio-cultural theory suggests that the information that is already known by users is contextually informed, hence sociocultural theory was applied to understand the contextual factors that could be used to enhance passphrase security and usability. With reference to the Southern African context, this study argues that system designers should take advantage of a multilingual user group and encourage the generation of passphrases that are based on substrings from different languages. This study went on to promote the use of multilingual passphrases instead of emphasising multi-character class passwords. This study was guided by design science research. Participants were invited to take part in a short password and multilingual passphrase generation and recall experiment that was made available using a web-based application. These passwords were generated by participants under pre-specified conditions. Quantitative and qualitative data was gathered. The study findings showed the use of both African and Indo-European languages in multilingual passphrases and short passwords. English oriented passwords and substrings dominated the multilingual passphrase and short password corpora. In addition, some of the short passwords and substrings in the multilingual passphrase corpora were found among the most common passwords of 2016, 2017 and 2018. Usability tests showed that multilingual passphrases are usable, even though they were not easy to create and recall when compared to short passwords. A high rate of password reuse during short password generation by participants might have worked in favour of short passwords. Nonetheless, participants appear to reflect better usability with multilingual passphrases over time due to repeated use. Females struggled to recall short passwords and multilingual passphrases when compared to their male counterparts. Security tests using the Probabilistic Context-Free Grammar suggest that short passwords are weaker, with just more than 50% of the short passwords being guessed, while none 4 Final Submission of Thesis, Dissertation or Research Report/Project, Conference or Exam Paper of the multilingual passphrases were guessed. Further analysis showed that short passwords that were oriented towards an IndoEuropean language were more easily guessed than African language-oriented short passwords. As such, this study encourages orienting passwords towards African languages while the use of multilingual passphrases is expected to offer more security. The use of African languages and multilingual passphrases by a user group that is biased towards English-oriented passwords could enhance security by increasing the search space.
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- Date Issued: 2019
Electrical, photo-thermal and mechanical degradation analysis of degraded single junction amorphous silicon solar modules
- Authors: Osayemwenre, Gilbert Omorodion
- Date: 2019
- Subjects: Solar cells Amorphous semiconductors Silicon
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15211 , vital:40204
- Description: In this present era of sustainable energy development, photovoltaic modules which are based on amorphous silicon cells have immeasurable prospects of contributing meaningfully to the energy demand of the world at large. The global consciousness of environmental safety issues has birthed the rapid demand for the photovoltaic system. However, the production increase is mainly in bulk-type crystalline (c-Si) solar cells. Thus, to meet the high demand of the market, single junction amorphous silicon (a-Si:H) solar cells production must be encouraged through active research in that regard. This could also help to improve its efficiency and reliability. There has recently been a sharp decrease in the production cost of the bulk Si solar cell, but the a-Si:H solar cell still remains the most economically viable in comparison to the other PV technologies. Companies such as Sharp are currently developing large-scale a-Si:H solar modules that can produce an efficiency of 10.5% after the long-term degradation process. To date, a-Si:H is believed to be one of the most promising thin-film PV technologies (Saito et al., 1993; Hamakawa et al., 1994). The cost of a solar PV manufacturing fell by 6% in 2014 (Santa, 2014), this is in accordance with the 2008 cost production forecast; thus, the cost record stands at 0.20 per watt, as reported by the NPD Solar publisher. Amorphous silicon (a-Si) solar modules generate more kilowatt-hour (kWh) of electricity per kilowatt (kW) than crystalline silicon or other technologies of the same capacity of installation. Furthermore, a-Si:H modules have more functional hours per day. Single junction amorphous silicon (a-Si:H) modules can function beyond the peak sun hours, and they also have a better performance on a cloudy day. vii In other words, a 1kW PV system of a-Si:H is expected to generate more electricity per year in comparison to 1kW PV from other technologies, hence there is a low energy payback time. In this study, commercially available single junction amorphous silicon modules were bought from a local market and they were immediately deployed outdoors. The initial reading of the modules, which served as baseline reading, showed an average of 25% decrease in the modules performance, therefore, there is a need for a long term monitoring process to obtain the best and worst performing modules. Measuring the performance parameters of these PV modules under real sun light (IV) provides a better degradation assessment. This conventional assessment cannot provide an in-depth insight responsible for the variation and degradation of the performance parameters. More obscured parameters like recombination current and ideality factor were obtained from the dark IV measurements. However, this is still superficial in a way. The intrinsic parameters were obtained from scanning probe microscopy (SPM) and CV measurements. The study focuses on the degradation analysis of a-Si:H due to an increase in defect density. A rise in the defect concentration is a huge problem because it causes long-term solar cell degradation, which increases the recombination current and decreases the conversion efficiency. Furthermore, it decreases the photo-generating current and reduces the effective efficiency of the solar device. In other words, the electrical output decreases. This research investigates the reduction in a-Si:H modules’ maximum power, and correlates these with a hot spot formation. A PVPM IV tracer was used for the outdoor characterisation of the module’s temperature profile, while the IR camera was used to analyse the hot spot centre. A four probe IV/CV from NMU was used for the indoor assessment of smaller samples cleaved from both the affected and non-affected regions to characterise the electrical variations across the module viii samples. To be precise, in this study, a naturally degraded single junction amorphous silicon module was delaminated and its mechanical properties were analysed and correlated with the contact potential from a Kelvin probe force microscopy (KPFM).
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- Date Issued: 2019
Land rental policy and land market in Mashonaland East Province, Zimbabwe: implications on farmer decisions, efficiency and equity under A1 and A2 models
- Authors: Tatsvarei , Simbarashe
- Date: 2019
- Subjects: Farms, Small Agricultural extension work
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15666 , vital:40501
- Description: Government promulgated the land rental policy starting in the year 2007. The policy required that A1 (market residual) and A2 (indigenous commercial) farmers pay rentals to the state. Since then, there has also been an emerging trend in which farmers have been renting in and out land, resulting in an informal market for land rentals. The study therefore assessed farmers’ perceptions of land rental policy and evaluated the possible association of this policy to farmers’ decision making on land rental markets as well as its implications on farmers’ efficiency and equity. The study was carried out in Mashonaland East Province of Zimbabwe, covering two districts, Goromonzi and Marondera. The focus was specifically on A1 and A2 farmers, as the rental policy was directed at these resettlement models only and much of the informal land rental markets were prevalent among these categories of farmers. Data collection utilised the survey approach. This was supported by key informant interviews and focus group discussions, with a final sample of 339 households selected using multi-stage sampling method. Survey data were transcribed on CsPro 6, and analysed using Stata, SPSS and Frontier 4.1. Results showed that about a third of household respondents was from Marondera and twothirds was from Goromonzi, while 79% and 21% was A1 and A2 farmers respectively. About 80% was male headed households and the remainder was female headed households. About half of the households were not participating in land rental markets while the other half was split almost equally between those renting-in and renting-out land. In general, A2 farmers were better in agricultural productivity than A1 farmers. It was concluded that farmers had a fairly good knowledge of the agricultural land rental policy enunciated in the Finance Bills. A1 farmers were more knowledgeable than A2 farmers, but no vii significant differences were observed between male and female headed households and farmers involved and not involved in land rental markets. Farmers’ attitudes in relation to policy were categorised as fair, with significant differences based on gender and land market participation. Practice scores showed a poor adherence to policy for all categories of farmers. Overall perceptions of farmers on rental policy was inferred as fair with significant differences existing between land rental market participants and non-participants (autarky). The results of a bivariate Tobit model results showed that the decision to rent-in land was significantly influenced by gender, household income, permanent labour, cultivated area, tenure certainty, irrigable land size and crop diversification. On the other hand, age, permanent labour, irrigable land size and crop diversification significantly influenced farmers’ decisions to rent-out land. The conclusion was that household characteristics, land endowments and transaction costs significantly influenced the decision to rent-in land while the former two were strong in influencing renting-out decisions. Results from the linearized Cobb Douglas model showed that economic efficiency for most farmers was above 50%. Farmers renting-out land under A1 were found to be the most economically efficient, followed by those who were renting-in and least efficient were farmers not participating in land rental markets, though the differences were marginal. For the A2 model, renting-in farmers were the most efficient, followed by those in autarky position, while renting-out farmers were the least. Overall, the most efficient farmers were those renting-in, followed by those renting-out while farmers in autarky were the least efficient. Overall efficiency was higher for A2 farmers than for A1 farmers. For farmers not participating in rental markets, the sources of inefficiency were crop type, crop area and labour. For farmers renting-in, it was proportion of irrigable land, size of irrigable land, crop type, crop area and viii labour, while inefficiency drivers for renting-out farmers were crop type and associated area. Equity analysis showed that participation in land rental markets reduced inequality for farmers in the two districts and male and female headed households. Inequality was increased among A1 farmers and remained unchanged among A2 farmers. Overall, the emerging position was that participation in land rental markets resulted in higher efficiency and reduced inequality in land holding among the sampled farmers. It is recommended that government should be consistent on land rental policy and bring into place effective administration of land rental policy. Government may also consider formal acceptance of land rental markets in light of the marginal efficiency and equity benefits shown in the study. However, formalizing land rental markets alone may not be a panacea to improved efficiency and needs to be supported by other productivity measures given the average efficiency values for farmers. Crop and livestock production based on compatibility with the natural regions and defined minimum size of land should be encouraged to improve efficiency
- Full Text:
- Date Issued: 2019
Customary marriage and family practices that discriminate against amaXhosa women: a critical study of selected isixhosa literary text
- Authors: Mbatyoti, Pheliwe Yvonne
- Date: 2019
- Subjects: Forced marriage -- South Africa -- Eastern Cape Customary law -- South Africa Xhosa (African people) -- Social life and customs
- Language: English
- Type: Thesis , Doctoral , D Litt et Phil (African Studies)
- Identifier: http://hdl.handle.net/10353/10736 , vital:35731
- Description: In many parts of Africa, the cultural practices and customs that were in use over the ages are still largely in place today. Many of these practices discriminate against individuals and compromise their human rights, particularly the rights of African women. The aim of this investigation is to study customary marital practices among the amaXhosa in order to establish their effect on modern amaXhosa society. In addition, this includes other discriminatory practices, such as the diminished status of wedded women. Within the study, the social status of women before and after 1994 is dealt with as depicted in the selected texts. The study further determines the current social status of married women under the current dispensation and finds out whether the rights of married women are sufficiently recognised in the texts under discussion. It is clear therefore that whilst Africa has made good progress on the political front, the same cannot be said for some of the cultural values that are still adhered to in the present age. This applies in particular to the rights of women in an African society. Globally, women and girls suffer the harmful and life-threatening effects of discriminatory traditional and cultural practices that continue under the guise of social, cultural and religious ceremonies. In the democratic South Africa, there is growing concern and awareness that some cultural practices are harmful to women and girls. The study analyses a number of texts namely, novels and drama, that were published before and after the 1994 era in South Africa with aims and objectives being outlined in Chapter 1. Chapter 2 is devoted to the theoretical framework, which includes the general theory pertaining to the status of women, feminism and human rights. Secondly, it deals with African theory pertaining to the status of African women as well as their rights; finally, it reflects on the role of women in societies where traditional marriage custom is still in use. Chapter 3 analyses the depiction of customary marriage as a theme in isiXhosa prose before and after 1994. Chapter 4 examines the depiction of customary marriage in v isiXhosa drama before and after 1994 and focuses more on human rights elements. Chapter 5 summarises the arguments distilled from the analysed works. The researcher came to the conclusion that the practice of forced marriage does not occur in amaXhosa society only but it is also found on a wider scale on the rest of the African continent and beyond. The study was concluded with a set of recommendations that were made to combat the scourge of anti-feminism that is found in modern society.
- Full Text:
- Date Issued: 2019
Physiological and mechanistic characteristics of all-out running using the critical speed concept
- Authors: Kramer, Mark
- Date: 2019
- Subjects: Aerobic exercises , Physical fitness Running Exercise
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/40511 , vital:36178
- Description: The studies described in this thesis, as far as could be ascertained, were the first to investigate the physiological and mechanistic characteristics of all-out running using the critical speed concept specifically applied to field-sport athletes. In the first study the oxygen uptake (𝑉̇𝑂2) kinetics of linear and shuttle all-out running were investigated. The 𝑉̇𝑂2 kinetic parameters were also related to parameters derived from a graded exercise test. No differences were observed in all 𝑉̇ 𝑂2 kinetic parameters between all-out linear and shuttle running, even though differences in all-out testing parameters were evident. The study was novel in that it was, as far as could be ascertained, the first to implement and investigate differences in 𝑉̇𝑂2 kinetics applied to all-out running. The second study investigated whether the parameters derived from all-out linear and shuttle running were representative of aerobic fitness, and the extent to which the all-out test (AOT) related to already established evaluations of aerobic fitness (e.g., graded exercise test [GXT] and the Yo-Yo intermittent recovery test [YYIR1]). It was also investigated whether the parameters from the AOTs could be used to predict the time to completion (tLIM) of shuttle-based performances. The outcomes of this study showed that both the linear and 50-m AOTs were indeed valid for the aerobic assessment of fitness by showing high correlations with maximal pulmonary oxygen uptake (𝑉̇𝑂2𝑚𝑎𝑥). Both the linear and 50-m AOT could therefore be used as surrogates for the evaluation of aerobic fitness. Interestingly, in terms of the tLIM prediction, the 25-m AOT showed the greatest utility. This study was novel on several fronts in that it was the first to: (1) investigate the physiological link between linear and shuttle AOTs and the GXT, (2) investigate the difference between AOTs and the YYIR1, and (3) investigate the application of the AOT methodology to field-based athletes such as rugby players. The third study investigated the energetic cost (EC) of locomotion as well as the metabolic power (𝑃̇) required to run at given speeds. The energetic approach provides a more robust evaluation of the differences between linear and shuttle running due to the all-out nature of the tests. Conventional methods of energy assessment often fall short due to the preclusion of a physiological steady-state, hence requiring more robust mathematical models to evaluate all-out running performance. The results of this study showed that differences between linear and shuttle AOTs are more likely neuromuscular as opposed to physiological. Peak EC and 𝑃̇ were significantly greater for shuttle running compared to linear running, showing clear non-linear increases with each successive increase in running speed. However, the mean EC and 𝑃̇ were not different, showing that all-out shuttle running ‘balances’ the lower running speeds (implying a lower physiological load compared to linear running) with the higher metabolic load imposed by the intense directional changes. This study was novel as it was, as far as could be ascertained, the first to apply the energetic approach to all-out running as well as investigate the differences in energetics between linear and shuttle AOTs. The fourth study provided a means by which the speed-time characteristics of all-out running could be objectively quantified. A novel bi-exponential model was applied to both the linear and shuttle speed-time curves and allowed various mechanistic aspects of the speed-time curve to be characterized. Conventional assessment of the AOT allows for the derivation of only two key parameters, namely critical speed (CS) and the finite distance achievable at speeds exceeding CS (D’). The application of the bi-exponential model expands the number of useful parameters that can be derived from an AOT to seven. The additional useful parameters include: maximum speed [𝑆𝑚𝑎𝑥], time to maximum speed [𝑡𝑐], amplitude of the difference between 𝑆𝑚𝑎𝑥 and CS [𝐴𝑑], curvature constant of the exponential decay [𝜏𝑑] and the asymptote of the exponential decay function [𝑆0], fatigue index showing the percent decline between 𝑆𝑚𝑎𝑥 and CS [FI%], and the finite capacity for running at speeds exceeding CS [D’; representing the area under the curve that is above CS]. The CS and D’ parameters derived from the bi-exponential model were not different to the CS and D’ parameters derived using the conventional method of analysis, thereby showing that the bi-exponential model is a valid means of assessing the curvature characteristics of the AOT, as well as providing additional information that cannot be gleaned from the traditional approach.
- Full Text:
- Date Issued: 2019
The influence of customers’ culture on sales promotions and store equity for pick n pay stores South Africa and Zimbabwe
- Authors: Musekiwa, Albert
- Date: 2019
- Subjects: Consumer behaviour
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/44565 , vital:38144
- Description: The store industry is globally the main distribution channel for grocery items to reach final consumers. Specifically for South Africa and Zimbabwe the store industry greatly contributes to the countrys economic growth. However, increasing competition in developed countries has forced store chains with a competitive edge in terms of promoting their brands and building market share such as Walmart and Spar to expand into the growing African market. Concomitantly, growing African store chains such as Choppies of Botswana are moving into new African markets such as South Africa and Zimbabwe. Following this increasing competition, Pick n Pay a leading store chain in South Africa has responded by opening stores in African townships and other African countries such as Zimbabwe. This has resulted in Pick n Pay customers’ cultural diversity, and how to build and maintain market share through effective promotional and brand building strategies being areas of concern. Therefore the primary objective of this study is to determine the influence of Pick n Pay customers’ cultural orientations on their buying behaviour towards monetary- and non-monetary sales promotions and store equity in South Africa and Zimbabwe. From a comprehensive literature review, a hypothesised model was developed to determine the customers’ cultural orientations that might influence the buying behaviour towards monetary- and non-monetary sales promotions and Pick n Pays store equity in South Africa and Zimbabwe. Four customers cultural orientations were investigated namely, ubuntu/unhu, power distance, uncertainty avoidance and status consumption. This quantitative research approach study sought the perceptions of Pick n Pays customers on their cultural orientations, buying behaviour towards monetary- and non-monetary sales promotions and on store equity in South Africa and Zimbabwe. A survey was conducted with the aid of a structured hardcopy questionnaire, distributed via fieldworkers in both countries using a combination of convenience- and snowball sampling. A final usable sample of 500 respondents was obtained. The items in the questionnaire were validated by conducting exploratory factor analysis, where after the Cronbachs alpha values were calculated for each of the valid constructs to confirm inter-item reliability. Descriptive statistics in the form of frequency distributions was used to summarise the demographic profiles of the respondents and to describe the means and standard deviations of the valid constructs. The Pearsons product moment correlations revealed moderate correlations between monetary- and non-monetary sales promotions as well as non-monetary sales promotions and store equity in the full sample, and for the South African and Zimbabwean samples. Moderate correlation was also found in South African sample between Ubuntu ubuntu/unhu cultural orientation and non-monetary sales promotions. Multi-collinearity diagnostics testing was conducted prior to multiple regression analysis to confirm that there is no evidence of collinearity between the independent-, mediating- and dependent variables. The multiple regression analysis revealed eight statistical significant relationships between the independent-, mediating- and dependent variables for the full sample while for the South African and Zimbabwean samples four and nine were found respectively. Although the full sample and Zimbabwean sample had similar statistically significant relationships, the relationship between an uncertainty avoidance cultural orientation and store equity was unique to the Zimbabwean sample only. There was only a statistically significant relationship between a power distance cultural orientation and store equity for the South African sample. Structural equation modelling was used as the main statistical procedure to test for mediation in the study. Only two relationships found in the multiple regression analysis were not confirmed in the structural equation modelling results, namely the relationships between an confirmed in the structural equation modelling results, namely the relationships between an uncertainty avoidance cultural orientation and monetary sales promotions, as well as with non-monetary sales promotions. Six path relationships were confirmed in the structured equation modelling. These statistical significant path relationships were between an ubuntu/unhu- cultural orientation with monetary- and non-monetary sales promotions, as well as with store equity. A statistical significant path relationships were also found between a status consumption cultural orientation with non-monetary sales promotions and store equity. The sixth statistical significant path relationship was between non-monetary sales promotions and store equity. Furthermore, SEM confirmed full mediation of monetary sales promotions in the relationship between a status consumption cultural orientation and store equity. On the other hand, there were partial mediations of non-monetary sales promotions in the relationships between an ubuntu/unhu and status consumption cultural orientations with store equity. The SEM results also confirmed that the data fits the complete model. Multi-variant analysis of variance was carried out to determine if respondents’ demographic profiles influenced their cultural orientations and buying behaviour towards monetary-and non-monetary sales promotions. Post-hoc Scheffe tests identified sixteen statistically significant mean differences between the demographic data groups and the cultural orientation and sales promotions variables. Subsequently, the Cohens d analysis confirmed thirteen practical significant relationships, of which only three had large practical significance. Based on the MRA and SEM confirmed relationships, several suggestions are made. Ubuntu/Unhu and status consumption cultural orientations influenced buying behaviour towards non-monetary sales promotions. For ubuntu/unhu orientated customers, it is suggested that Pick n Pay keeps its non-monetary sales promotions open and accessible to most customers and sponsor more popular events such as competitions for baking, cooking and soccer. To target status consumption orientated customers, Pick n Pay should position its non-monetary sales promotions in line with their expectations such as promoting healthy living to appeal to its healthy conscious customers. Pick n Pay should also avoid making price the focal point when communicating to status consumption orientated consumers but rather focus on image building selling points such as store service. For ubuntu/unhu orientated customers, Pick n Pay should underscore the interdependence value in its communication of monetary sales promotions by offering monetary promotions with benefits for all family members. To entrench brand equity, Pick n Pay should engage ubuntu/unhu brand ambassadors from influential family members, friends and community groups such as church groups and provide after-sales service using 24hr customer service hotlines and social media to promote customer interaction any time of the day. Pick n Pay must consider entrenching the status consumption health conscious customers into interaction between themselves or the store through chatrooms or clubs to make sure they remain loyal to the store. It is recommended that Pick n Pay conduct non-monetary sales promotion by creating awareness campaigns for its organic and finest private brands in their Fresh Living Magazine so that customers have product knowledge and encourage them to become regular buyers. In-store distribution of product samples can also help build interest in the brands. Furthermore, employing data mining techniques on customer databases provided in Smartshopper and Rich Rewards loyalty programmes can help understanding specific target customer groups and developing target marketing campaigns. For status consumption orientated customers, Pick n Pay can incentivise the adoption of online shopping through sales promotions such as free delivery for first time shoppers. The store can also have personalised free rewards for its most loyal customers. For ubuntu/unhu orientated customers, it is recommended that Pick n Pay engage in corporate social responsibility that target the needy in the society such as donating to elderly and orphanages and request their customers to donate their loyalty points to charities of their own choices. It is suggested that Pick n Pay promote excellent service and a wide variety of quality products to ensure their status consumption orientated customers remain loyal to the store. They can also offer a suggestions box for these customers to make them feel heard. Their employees should be selected based on contemporary skills such as digital- and green marketing and healthy living product knowledge and they should train their current employees on these areas to enable addressing customers’ queries confidently. This study has added to scarce academic literature on customers’ cultural orientations, sales promotion buying behaviour and store equity in Africa in general. From the hypothesised model developed in this study, a significant contribution has been made in the body of knowledge on the influence of customers’ culture on buying behaviour towards sales promotions and store equity, especially in the retail field for stores such as Pick n Pay. This study was also the first to identify the major role demographics can play in customers’ cultural orientations and sales promotion buying behaviour. The recommendations can be useful to assist with developing marketing strategies suitable for any retail store such as Pick n Pay which wants to venture into African markets.
- Full Text:
- Date Issued: 2019
Evaluation of groundwater potential based on hybrid approach of geology, geophysics, and geoinformatics: Case study of Buffalo Catchment area, Eastern Cape, South Africa
- Authors: Owolabi,Solomon T
- Date: 2019
- Subjects: Hydrogeology Geology
- Language: English
- Type: Thesis , Doctoral , PhD (Geology)
- Identifier: http://hdl.handle.net/10353/12238 , vital:39218
- Description: This study focuses on the feasibility of exploring potential groundwater zones through assessment of catchment geo-hydrodynamic processes, using hydro-statistic principles and geographic information system-based approaches. The research work integrated analysis of hydrologic variables, geologic structures, and geomorpho-tectonic processes that provide information on spatial variability of hydrologic units in a watershed. The study is aimed at improving conceptual knowledge and presenting the technical feasibility of exploring potential groundwater zones through geo-hydrodynamic perspectives in hydrogeologically challenged environments. The study adopted a case design approach at the Buffalo hydrologic basin headwater in Eastern Cape, South Africa. The methods used in this study include: field mapping of geologic units and structures, digital processing of aeromagnetic map, cross-section profiling of borehole logs, auto-extraction of lineament, streamflow variability and recession assessment, geomorpho-tectonic analysis of surficial drainage pattern, vertical electrical sounding for imaging shallow subsurface layers, and geospatial integration of thematic maps of groundwater multi-influencing factors. The results indicate that the hydrogeological settings of Buffalo watershed comprised of good, moderate, fair, poor and very poor groundwater potential zones which cover 187 km2 , 338 km2 , 406 km2 , 185 km2 , and 121 km2 respectively. The results report that the groundwater system of Buffalo watershed is mainly hosted by the well-drained fractured dolerite and the shallow unconfined sandstone aquifer. The aquifer is bounded by two parallel impermeable valley walls in the north and south. Also, the Buffalo drainage system constitutes a variable head boundary as a groundwater discharge zone. The groundwater discharge which mostly occurs at the Tshoxa upper course, Mgqakwebe, Quencwe, Yellowwoods upper course and the Buffalo River center influence the status of the Buffalo River as a perennial river system. vi The groundwater recharge occurs through the networks of surficial lineaments and fractures concentrated on the sandstone lithosome, mostly in the northern half of the watershed. The surficial tectonic features trend in a WNW-ESE and E-W direction. The groundwater flow system is controlled by the subsurface lineaments which are oriented in west-northwest – eastsoutheast direction. Most of the groundwater recharge is driven by rain which is extreme at the north. The hydro-climatic pattern of the region influences the dendritic drainage system of Buffalo watershed. The geologic characterization and geomorpho-tectonic analysis indicate that the geologic settings are made up of upward-fining lithologic material and siliciclastic materials that were deposited as fill in paleochannels by braided and meandering fluvial systems. The variability in dissection property and the fluvial system indicates that Buffalo hydrologic and geomorphic systems are heterogeneous and complex. The possible impact of these variabilities aligns with the report of geoelectric sections which revealed the heterogeneity of the aquifer intrinsic properties and variability in groundwater yield. The electric resistivity tomography revealed the existence of a fault system and variation in the thickness of the aquifer. Hydrologic characterization indicates the vulnerability status of the rivers within the watershed. In particular, the Ngqokweni River is vulnerable to diminution while Quencwe River has the potential for a flash flood. Buffalo station is an important surface water capture zone. Delineation of groundwater potential zone should incorporate geologic, hydrologic, geophysical, geomorphotectonic, and environmental perspectives due to the inherent relationship among influencing factors. The study therefore identifies groundwater capture zones which can be further explored for groundwater development and to mitigate the stake of water shortage. The study therefore recommends the approach here to the department of water affairs for adoption to map the zones of groundwater potential at a regional scale. The study also provides resourceful information on vii groundwater recharge zones and therefore recommends that the environment and water stakeholders work together to protect the recharge zones from groundwater contamination due to land use
- Full Text:
- Date Issued: 2019
Pyramidal deliberative democracy
- Authors: Danielsen, James
- Date: 2019
- Subjects: Democracy , Information technology -- Political aspects , Internet in public administration , Political participation -- Computer network resources , World politics
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/74502 , vital:30309
- Description: This dissertation has two main objectives. First, to outline an ICT-facilitated model of democracy called ‘pyramidal democracy’ that reconciles deliberative democracy with mass engagement. Second, to suggest how this model of democracy might engender the democratisation of the global economy and thus the provision of a basic level of economic security for all global citizens. At the core of the model is the pyramidal deliberative network, a means of organising citizens into small online deliberative groups and linking these groups together by means of an iterative process of delegate-selection and group-formation. The pyramidal network enables citizens to aggregate their preferences in a deliberative manner, and then project social power by authorizing the delegates at the top-tier of the pyramidal network to communicate their social demands to elected officials or to other points of authority. The envisioned outcome is the democratisation of the public sphere by means of the proliferation of deliberative networks in the government, market, and civil society spheres. Transnational pyramidal networks may make it feasible to instantiate a new citizen-based schema of global governance and, thereby, facilitate the reform of the United Nations and enable a transition towards global peace, sustainability, and distributive justice. Distributive justice might be achieved by means of implementing the six components of a democratised economy: participatory budgeting, fee-and-dividend taxes, a basic income, monetary reform, workplace democracy, and the sharing economy. Taken together, these components might enable the universal provision of a social minimum – a universal basic income sufficient for basic security and real freedom. Taken to its logical conclusion, a democratised economy may also enable a transition towards a post-scarcity economic order characterised by a maximal stock of humanmade and natural capital that would not exceed the sustainable carrying capacity of the earth.
- Full Text:
- Date Issued: 2019
Political education as a determinant of university students’ political participation in the Eastern Cape, South Africa
- Authors: Badaru, Kazeem Ajasa
- Date: 2019
- Subjects: Citizenship -- Study and teaching -- South Africa Democracy and education -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10353/15793 , vital:40524
- Description: Globally, there is a downward trend in youths’ political interest and participation in the learning of political education in their school curricula as a measure to combat the apparent dangers posed by the declining young citizens’ participation in the political processes.This study therefore investigated political education as a determinant of university students’ political participation in the Province of the Eastern Cape, South Africa. The study employed a mixed methods design. Using the probability sampling technique, a sample of 375 participants was randomly selected from one university in the Eastern Cape Province while semi-structured interviews were conducted among five (5) purposively selected members of the same university’s Student Representative Council (SRC) executive committee. Simple descriptive statistics such as frequency counts and percentages were used to summarize all categories of variables; while Pearson correlation statistics, Chi-square and Ordinary least square regression were used to examine the relationship between dependent and independent variables at a 95percent confidence interval. Alpha values less than 0.05 were considered to be statistically significant. Thematic content analysis was performed on the qualitative data. The quantitative analysis revealed that students’ level of political awareness was high; 98.1percent of them were aware of their rights to vote and be voted for. Students’ political judgment was positively correlated with participation in campus (r =0.182) and national politics (r = 0.030) respectively. Most of the students agreed to take part in the 2018 SRC (78.8percent) and 2019 national elections (77.9percent) respectively. Political interest was significantly correlated with participation in campus (r = 0.375) and national politics (r =0. 404). The findings from the multivariate analysis showed that political interest (<0.001), parents’ political involvement (<0.001) and year of study (<0.001) were the significant determinants of students’ participation in politics. The qualitative findings also showed that there was a positive relationship between political education and students’ participation in politics. Since political interest and family are element and agent of political education respectively, it is concluded that political education is to a large extent a determinant of university students’ political participation. It is recommended that the universities, the Department of Higher Education and Training (DHET) and other stakeholders should do a thorough review of the university education curricula and programmes to ensure that political education is adequately accommodated and taken care of in a way that would increase students’ interest, awareness and participation in politics. When this is amply done, students’ cognitive skills and capacities would be enhanced to increase their participation in the political processes in South Africa.
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- Date Issued: 2019
A critical realist exploration of the culture of resistance in educational technology integration practices at a South African university
- Authors: Tshuma, Nompilo
- Date: 2019
- Subjects: Critical realism , Educational technology -- South Africa , Education, Higher -- Effect of technological innovations on -- South Africa , College teachers -- South Africa , College teaching -- Sociological aspects -- South Africa
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/72318 , vital:30033
- Description: This thesis seeks to address a number of troubling concerns related to research and practice in the field of educational technology in South African higher education. Firstly, educational technology research has been criticised for a lack of theoretical rigour resulting in perspectives that are tightly focused mostly on practice but fail to adequately interrogate the socio-political complexities of integrating educational technology. Secondly, while research in the field has been criticised for failing to adequately contextualise the study of educational technology, it also fails to interrogate the impact of colonial legacies and Western-developed technologies on integration practices. Thirdly, there seems to be a disconnect between academics’ practices and choices with educational technology, and the expectations and assumptions of educational technologists. As such, this thesis predominantly follows inductive reasoning where literature and theory are applied to the empirical situation retrospectively in order to avoid the potential influences and biases of mostly Western-driven discourses on educational technology integration practices. Critical realism is used to ‘underlabour’ this study. This meta-theory asserts that there are multiple perspectives of an independent reality, and the work of research is to use these perspectives to draw closer to an understanding of that reality. As such, it allows me to interrogate my perspectives firstly, and secondly those of my research participants, about factors that constrain educational technology integration in the South African context through the use of theory (abstract concepts) and data (research participants’ multiple perspectives). However, critical realism is somewhat cautious in how to access this reality. Therefore, a critical ethnographic epistemology is employed to strengthen critical realism’s aim of accessing knowledge. A critical epistemology emphasises exposing hidden power structures, value judgements as well as self-knowledge and reflexivity. The thesis thus shows how a critical realist ontology could be complemented by a critical ethnographic methodology, particularly in critically-orientated research that has an emancipatory focus which seeks to uncover the socio-political context within which educational technology practices take place. A key argument is that critical realism can be employed as an ontological underlabourer for critical research because of: 1) its immanent critique of traditionally-accepted philosophies, 2) its emphasis on critique of our knowledge claims and value judgements, 3) its insistence that knowledge of the social world necessarily precedes emancipation, and 4) its different conceptions of power (oppressive power and transformatory power). This critical ethnographic research is conducted in a South African university with eight female academics. Data collection is in the form of interviews, observations and reflections, as well as informal and work-related interactions. At each data collection moment, I have had to be reflexively aware of my positionality as an educational technologist, the impact of a colonially-motivated methodology and an ethically-aware approach that seeks to put the needs of the research participants first. Critical ethnography’s meaning-making and critical realism’s abduction and retroduction are used to analyse and make sense of the data. In my attempt to contextualise the study’s findings, I first uncover structural forces and their impact on the academic role before attempting to correlate this with educational technology practices. The study’s findings point to two main structural forces in the socio-political context of South African higher education: the teaching/research tension and the elevation of one dominant culture. In terms of the teaching/research tension, the female academics in this study have to balance the urgent teaching function with the valued research function. They struggle to find this balance because of ambiguous messages from different structures, their passion for teaching, oppressive departmental dynamics and the pressures of their career trajectory. The elevation of one dominant culture is demonstrated through both oppressive cultural practices and untransformed curricula. The study shows that academics mitigate these structural constraints mostly through subtle every day resistance that seeks to mitigate their effect on both the academics and, where applicable, their students. Archer’s morphogenetic/morphostatic cycle is used retrospectively, in response to fieldwork, to conceptualise why this resistance comes about. A resistance framework developed using Archer is then used to understand educational technology choices and practices. The results of the research show that while academics are often pictured as resistant to technology as a response to different barriers, they actually often employ technology to resist structural forces. That is, with this thesis I show that there is a focus on resistance with technology rather than resistance to technology. The study shows how the research participants resist structural forces (teaching tension and dominant culture) by using technology to create safe and responsive learning spaces. As such, this thesis challenges educational technologists to re-think the way they support academics by recommending support strategies that acknowledge both the structural forces in the South African higher education context, as well as the culture of resistance, both of which impact academics’ educational technology choices and practices.
- Full Text:
- Date Issued: 2019
Design of metal ion-selective reagents for recovery of precious metals
- Authors: Moleko-Boyce, Pulleng
- Date: 2019
- Subjects: Bioinorganic chemistry , Metal complexes Speciation (Chemistry)
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/42510 , vital:36664
- Description: The study is divided into two sections; namely, (1) the design of rhodium(III) specific chelating ligands (tridentate bis-benzimidazole derivatives), and (2) the development of iridium(IV)-specific quaternary diammonium cations with electron donating and electron withdrawing groups. Bis-benzimidazole chelating ligands used were bis((1H-benzimidazol-2-yl)methyl)amine (NNN1), bis((1H-benzimidazol-2-yl)ethyl)amine (NNN2), bis((1H-benzimidazol-2-yl)methyl)sulfide (NSN1) and bis((1H-benzimidazol-2-yl)ethyl)sulfide (NSN2). Quaternary diammonium cations used were tetramethylbenzyl-1,10-diammonium chloride (QuatDMDAMeBnz), tetrabenzyl-1,10-diammonium chloride (QuatDMDABnz), tetratrifluoromethylbenzyl-1,10-diammonium chloride (QuatDMDACF3Bnz) and tetranitrobenzyl-1,10-diammonium chloride (QuatDMDANO2Bnz). For both studies, polyvinylbenzylchloride (PVBC) nanofibers were used as support material. The PVBC nanofibers which were functionalised with bis-benzimidazole derivatives and quaternary diammonium cations, respectively, were investigated for the selectivity for Rh(III) over Ir(III), Pt(II), Pd(II) and Ni(II), and for separation of Ir(IV) from Rh(III), respectively. The sorbent materials were characterised by FTIR, SEM, BET surface area, TGA, EDS and elemental analysis, and the results showed that the functionalization of the sorbent materials was successful.The efficiency of bis-benzimidazole derivatives and quaternary diammonium cations, respectively, were investigated in a column study under dynamic flow adsorption conditions. The adsorption kinetics and isotherms were investigated under batch conditions and fitted on pseudo-first-order and pseudo-second-order model, and Freundlich and Langmuir isotherm, respectively. It was observed that the bis-benzimidazole derivatives showed uptake of [RhCl3(H2O)3], and the loading capacities were observed in the following order; NSN1 (181.06 mg/g) > NSN2 (148.55 mg/g) > NNN1 (131.88 mg/g) > NNN2 (75.87 mg/g). The bis-benzimidazole derivatives preference for metal ions was further investigated with a multi-element solution containing Rh(III), Ir(III), Pt(II), Pd(II) and Ni(II). The bis-benzimidazole derivatives showed the following order of loading capacity: NSN1 (47.28 mg/g) > NSN2 (23.89 mg/g) > NNN1 (17.47 mg/g) > NNN2 (14.91 mg/g) for Rh(III); NSN2 (10.64 mg/g) > NNN2 (6.84 mg/g) > NSN1 (5.74 mg/g) > NNN1 (5.02 mg/g) for Ir(III); NNN2 (33.96 mg/g) > NSN1 (30.95 mg/g) > NSN2 (19.95 mg/g) > NNN1 (14.92 mg/g) for Pt(II); NNN1 (47.94 mg/g) > NNN2 (28.90 mg/g) > NSN1 (16.22 mg/g) > NSN2 (15.83 mg/g) for Pd(II). Bis-benzimidazole derivatives showed no uptake of nickel(II) under these conditions. It was observed the ligand-selectivity order for Rh(III) was similar in both single-element and multi-element studies. This order showed that the bis-benzimidazoles containing a sulfur atom showed a high preference for rhodium(III) compared to Pt(II) which had a high preference for NNN2 as well as Pd(II) which had a high preference for NNN1. Ir(III) generally had a lower preference for the ligands presumably due to its higher kinetic inertness compared with Rh(III). Column sorption of [IrCl6]2- and [RhCl5(H2O)]2- on nanofibers functionalized with diammonium cations was carried out and the loading capacities of [IrCl6]2- were obtained. [RhCl5(H2O)]2- was not adsorbed by the sorbent materials while [IrCl6]2- was loaded onto the column. The loading capacities of [IrCl6]2- with the quaternary diammonium sorbent materials increased in the order of F-QuatDMDAMeBnz (60.29 mg/g) < F-QuatDMDABnz (67.61 mg/g) < F-QuatDMDACF3Bnz (107.59 mg/g) < F-QuatDMDANO2Bnz (140.47 mg/g). The loading capacity for Ir(IV) with quaternary diammonium cationic nanofibers increased with an increase in the electron-withdrawing nature of the quaternizing group. The charge delocalizing ability of the nitrobenzyl group resulted in the best interaction of the diammonium cation with [IrCl6]2-. Batch equilibrium studies were carried out to assess the efficiency of bis-benzimidazole chelating derivatives as adsorbents using a multi-metal solution (Rh(III), Ir(III), Pt(II), Pd(II) and Ni(II)) in 0.5 M HCl. The efficiency of the quaternary diammonium cations was tested using a binary metal solution (Ir(IV) and Rh(III)) in 6 M HCl. The isothermal batch adsorption studies of a multi-metal solution with bis-benzimidazoles derivatives fitted the Langmuir isotherm model which confirmed monolayer adsorption onto a homogeneous surface. The Langmuir isotherm parameter (qe (mg/g)), using functionalized nanofibers, showed the order of NNN2 (128.21 mg/g) > NSN1 (99.01 mg/g) > NSN2 (91.74 mg/g) > NNN1 (84.03 mg/g) for Pt(II); NNN1 (66.23 mg/g) > NNN2 (5.89 mg/g) > NSN1 (1.40 mg/g) > NSN2 (0.59 mg/g) for Pd(II); NSN2 (10.64 mg/g) > NNN2 (6.84 mg/g) > NSN1 (5.74 mg/g) > NNN1 (5.02 mg/g) for Ir(III); NSN1 (140.85 mg/g) > NSN2 (109.89 mg/g) > NNN1 (104.17 mg/g) > NNN2 (91.74 mg/g) for Rh(III). The pseudo-first-order kinetics model was found to be the best fit to describe the adsorption kinetics of all metal ions onto all the sorbent materials. K1 (min-1) value in pseudo-first-order kinetics showed the same order of adsorption as observed in the Langmuir isotherms. The isothermal batch adsorption studies of [IrCl6]2- and [RhCl5(H2O)]2- with quaternary diammonium cations fitted the Freundlich isotherm model and confirmed to be effective for multiple-layered adsorption onto a heterogeneous surface. The Freundlich isotherm parameter (kf (mg/g)) using functionalized quaternary diammonium cationic nanofibers increased in the order of F-QuatDMDANO2Bnz (794.33 mg/g) > F-QuatDMDACF3Bnz (185.35 mg/g) > F-QuatDMDABnz (156.32 mg/g) > F-QuatDMDAMeBnz (112.46 mg/g) for Ir(IV) uptake. F-QuatDMDANO2Bnz resin showed the highest adsorption than that of F-QuatDMDAMeBnz, F-QuatDMDABnz and F-QuatDMDACF3Bnz and this order is similar to what was observed in column studies. The quaternary diammonium cations were shown to have the highest adsorption capacity for Ir(IV) compared with Rh(III). The adsorption of Rh(III) was also observed to increase in the order of F-QuatDMDANO2Bnz (177.83 mg/g) > F-QuatDMDACF3Bnz (40.37 mg/g) > F-QuatDMDABnz (36.98 mg/g) > F-QuatDMDAMeBnz (12.71 mg/g). The pseudo-second-order kinetic model was found to be the best fit to describe the adsorption kinetics of both metal ions onto all the sorbent materials. K2 (g.mg-1min-1) value in pseudo-second-order kinetics showed the same order of adsorption as observed in the Freundlich isotherms. The adsorption studies showed adsorption takes place via chemisorption process. This thesis presents PGMs and iridium-specific materials that could be applied in solutions of secondary PGMs sources containing rhodium, platinum and palladium with bis-benzimidazoles as well as in feed solutions from ore processing with diammonium cations for iridium recovery.
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- Date Issued: 2019