Case study : profitability drivers in the South African airline industry : a comparative analysis of SAA and Comair
- Authors: Batidzirai, Davison Herbert
- Date: 2015
- Subjects: South African Airways , Comair Limited , Airlines -- South Africa , Corporate profits -- South Africa , Organizational effectiveness -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:846 , http://hdl.handle.net/10962/d1017191
- Full Text:
- Date Issued: 2015
- Authors: Batidzirai, Davison Herbert
- Date: 2015
- Subjects: South African Airways , Comair Limited , Airlines -- South Africa , Corporate profits -- South Africa , Organizational effectiveness -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:846 , http://hdl.handle.net/10962/d1017191
- Full Text:
- Date Issued: 2015
Short-term changes to the life history of shad, Pomatomus saltatrix (Perciformes: Pomatomidae), in Southern Angola
- Authors: Bealey, Roy Steven John
- Date: 2015
- Subjects: Shad -- Angola , Bluefish -- Angola , Bluefish -- Climatic factors -- Angola , Bluefish -- Effect of temperature on -- Angola , Bluefish -- Effect of global warming on -- Angola , Bluefish -- Effect of fishing on -- Angola , Bluefish -- Life cycles , Pomatomidae -- Angola , Fishery management -- Angola , Climatic changes -- Angola
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5379 , http://hdl.handle.net/10962/d1017211
- Description: A general lack of biological information is hampering the effective management of Angola’s fisheries. While this lack of information is largely a result of the country’s extended civil war that ended in 2002, the subsequent rapid expansion of fisheries is most likely impacting fish abundance and influencing the biology of this regions fishes. Besides the influence of fisheries, the southern Angolan coastal region is considered to be a climate change “hotspot” due to rapidly (>0.8°C/decade) increasing water temperatures. These changes are thought to drive further changes to the biology of fishes. It is therefore critical to provide baseline biological information and to identify the impacts of exploitation and warming on the biology of southern Angolan fishes. Pomatomus saltatrix is a warm-temperate marine fish species that forms an important component of fisheries throughout its broad distribution. P. saltatrix is a migratory predator that displays variable growth and maturity schedules. Typically it is heavily targeted in a range of coastal fisheries of Angola and is therefore an ideal candidate to study the biological impacts of exploitation and climate change. The aim of this study was to provide the first description of P. saltatrix biology in Angola and examine recent changes of the species biological parameters in an attempt to uncouple fishery driven from climate driven changes. Samples of P. saltatrix were collected monthly using standardised biological methods from June 2005 to December 2006 (period 1) and from June 2012 to February 2013 (period 2). The average (508mm – 1st period, 462mm – 2nd period) and maximum (760mm – 1st period, 746mm – 2nd period) size of P. saltatrix was smaller during the second period to suggest selective overharvesting of large individuals by developing fisheries. Angolan P. saltatrix grew very rapidly in their first year and thereafter, relatively slowly when compared to other populations globally. However, fish grew faster (ω = 103 – 1st period, ω = 124 – 2nd period), matured at a larger size (303mm - 1st period, 336mm - 2nd period) and younger age (0.83 years - 1st period, 0.67 years – 2nd period) during the second period. Peaks in reproductive activity remained similar (November) during both periods but a temperature anomaly appears to have influenced spawning during period 2. Sardinella aurita was the dominant prey during both periods but a greater dependence upon mugilids was observed during the second period. Although the changes in life history were not statistically significant, the faster growth observed during period two could be attributed to both increasing temperature and/or exploitation. Fishes generally grow faster, mature smaller and attain a smaller maximum size in warmer temperatures. Fisheries targeting small and large specimens of a species (as observed in this study) largely have the same impacts as ocean warming. With rapidly increasing water temperatures and exploitation rates, faster growth and earlier maturation of P. saltatrix populations will mitigate the impacts of exploitation in the short-term. However, the sustainability of Angola’s P. saltatrix stock is questionable as phenotypic adaptation will have a limited thermal scope and overexploitation will, like in all fisheries, negatively influence recruitment. Ultimately, strict monitoring, regulation and control will be necessary to ensure the sustainability of the P. saltatrix resource in Angola as it continues to face increasing anthropogenic and environmental pressures. Management guidelines and future research suggestions are therefore outlined with reference to the results of analyses conducted during this study.
- Full Text:
- Date Issued: 2015
- Authors: Bealey, Roy Steven John
- Date: 2015
- Subjects: Shad -- Angola , Bluefish -- Angola , Bluefish -- Climatic factors -- Angola , Bluefish -- Effect of temperature on -- Angola , Bluefish -- Effect of global warming on -- Angola , Bluefish -- Effect of fishing on -- Angola , Bluefish -- Life cycles , Pomatomidae -- Angola , Fishery management -- Angola , Climatic changes -- Angola
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5379 , http://hdl.handle.net/10962/d1017211
- Description: A general lack of biological information is hampering the effective management of Angola’s fisheries. While this lack of information is largely a result of the country’s extended civil war that ended in 2002, the subsequent rapid expansion of fisheries is most likely impacting fish abundance and influencing the biology of this regions fishes. Besides the influence of fisheries, the southern Angolan coastal region is considered to be a climate change “hotspot” due to rapidly (>0.8°C/decade) increasing water temperatures. These changes are thought to drive further changes to the biology of fishes. It is therefore critical to provide baseline biological information and to identify the impacts of exploitation and warming on the biology of southern Angolan fishes. Pomatomus saltatrix is a warm-temperate marine fish species that forms an important component of fisheries throughout its broad distribution. P. saltatrix is a migratory predator that displays variable growth and maturity schedules. Typically it is heavily targeted in a range of coastal fisheries of Angola and is therefore an ideal candidate to study the biological impacts of exploitation and climate change. The aim of this study was to provide the first description of P. saltatrix biology in Angola and examine recent changes of the species biological parameters in an attempt to uncouple fishery driven from climate driven changes. Samples of P. saltatrix were collected monthly using standardised biological methods from June 2005 to December 2006 (period 1) and from June 2012 to February 2013 (period 2). The average (508mm – 1st period, 462mm – 2nd period) and maximum (760mm – 1st period, 746mm – 2nd period) size of P. saltatrix was smaller during the second period to suggest selective overharvesting of large individuals by developing fisheries. Angolan P. saltatrix grew very rapidly in their first year and thereafter, relatively slowly when compared to other populations globally. However, fish grew faster (ω = 103 – 1st period, ω = 124 – 2nd period), matured at a larger size (303mm - 1st period, 336mm - 2nd period) and younger age (0.83 years - 1st period, 0.67 years – 2nd period) during the second period. Peaks in reproductive activity remained similar (November) during both periods but a temperature anomaly appears to have influenced spawning during period 2. Sardinella aurita was the dominant prey during both periods but a greater dependence upon mugilids was observed during the second period. Although the changes in life history were not statistically significant, the faster growth observed during period two could be attributed to both increasing temperature and/or exploitation. Fishes generally grow faster, mature smaller and attain a smaller maximum size in warmer temperatures. Fisheries targeting small and large specimens of a species (as observed in this study) largely have the same impacts as ocean warming. With rapidly increasing water temperatures and exploitation rates, faster growth and earlier maturation of P. saltatrix populations will mitigate the impacts of exploitation in the short-term. However, the sustainability of Angola’s P. saltatrix stock is questionable as phenotypic adaptation will have a limited thermal scope and overexploitation will, like in all fisheries, negatively influence recruitment. Ultimately, strict monitoring, regulation and control will be necessary to ensure the sustainability of the P. saltatrix resource in Angola as it continues to face increasing anthropogenic and environmental pressures. Management guidelines and future research suggestions are therefore outlined with reference to the results of analyses conducted during this study.
- Full Text:
- Date Issued: 2015
Appraising the appraisal framework: evidence from Grahamstown property advertisements
- Authors: Beangstrom, Tracy
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/54744 , vital:26608
- Description: This thesis considers how interpersonal meaning choices in property advertisements are best reflected in a context of constraint in Grahamstown, South Africa, using and appraising Martin & White’s (2005) APPRAISAL Framework. The study is comparative in two senses since the data is analysed using Martin & White’s (2005) APPRAISAL Framework and a revision to it, and property advertisements from two competing estate agencies are analysed: Remax Frontier Properties and Pam Golding Properties. An initial strict application of Martin & White’s (2005) framework is followed by a second, based on analyst difficulties and framework limitations experienced in the first analysis, as well as those experienced by other researchers. Revisions to the original framework include added ‘local’, context-driven features and sub-categories: Exclusivity and Convenience in Attitude, a Scale of Intensity in Graduation, and a category ‘Invite’ in Engagement. These enable a richer, more detailed account of the alignment strategies and interpersonal micro-politics at play in the property advertisements than is possible using the original framework. Findings from the analyses reveal four facts of note. Firstly, that while the original Martin & White (2005) APPRAISAL Framework captures a general level of interpersonal meaning in the data, it does so more fully when it includes contextual and contextually-driven categories that are informed by local knowledge. Secondly, two levels of meaning are expressed in the data. One is aimed at an ‘external’ audience; the other, truer, fuller and more contentious, is aimed at what appears to be the intended audience only. Thirdly, and relatedly, specific contextual and cultural knowledge is needed by the intended audience to access the intended meaning. Fourthly, both estate agencies promote values of high prestige, exclusivity, elitism and wealth as their intended meaning to align a like-minded audience, although Remax Frontier Properties attribute these values to location and features of the home to a greater extent than Pam Golding Properties, who place greater emphasis on the size of the home. The thesis suggests further avenues for research into the discourse of property advertising, as well as into overcoming certain context-specific limitations of the APPRAISAL Framework.
- Full Text:
- Date Issued: 2015
- Authors: Beangstrom, Tracy
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/54744 , vital:26608
- Description: This thesis considers how interpersonal meaning choices in property advertisements are best reflected in a context of constraint in Grahamstown, South Africa, using and appraising Martin & White’s (2005) APPRAISAL Framework. The study is comparative in two senses since the data is analysed using Martin & White’s (2005) APPRAISAL Framework and a revision to it, and property advertisements from two competing estate agencies are analysed: Remax Frontier Properties and Pam Golding Properties. An initial strict application of Martin & White’s (2005) framework is followed by a second, based on analyst difficulties and framework limitations experienced in the first analysis, as well as those experienced by other researchers. Revisions to the original framework include added ‘local’, context-driven features and sub-categories: Exclusivity and Convenience in Attitude, a Scale of Intensity in Graduation, and a category ‘Invite’ in Engagement. These enable a richer, more detailed account of the alignment strategies and interpersonal micro-politics at play in the property advertisements than is possible using the original framework. Findings from the analyses reveal four facts of note. Firstly, that while the original Martin & White (2005) APPRAISAL Framework captures a general level of interpersonal meaning in the data, it does so more fully when it includes contextual and contextually-driven categories that are informed by local knowledge. Secondly, two levels of meaning are expressed in the data. One is aimed at an ‘external’ audience; the other, truer, fuller and more contentious, is aimed at what appears to be the intended audience only. Thirdly, and relatedly, specific contextual and cultural knowledge is needed by the intended audience to access the intended meaning. Fourthly, both estate agencies promote values of high prestige, exclusivity, elitism and wealth as their intended meaning to align a like-minded audience, although Remax Frontier Properties attribute these values to location and features of the home to a greater extent than Pam Golding Properties, who place greater emphasis on the size of the home. The thesis suggests further avenues for research into the discourse of property advertising, as well as into overcoming certain context-specific limitations of the APPRAISAL Framework.
- Full Text:
- Date Issued: 2015
Structural controls of gold mineralisation in Seguelen pit of Siguiri gold mine, Guinea
- Authors: Beavogui, Massa
- Date: 2015
- Subjects: AngloGold Ashanti Ltd. , Gold mines and mining -- Guinea -- Siguiri (Region) , Geochemical surveys -- Guinea -- Siguiri (Region) , Geology, Structural -- Guinea -- Siguiri (Region) , Faults (Geology) -- Guinea -- Siguiri (Region) , Folds (Geology) -- Guinea -- Siguiri (Region) , Turbidites -- Guinea -- Siguiri (Region) , Metamorphism (Geology) -- Guinea -- Siguiri (Region) , Hydrothermal alteration -- Guinea -- Siguiri (Region)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5091 , http://hdl.handle.net/10962/d1019879
- Description: The present study provides the results of detailed mapping and analysis of structures encountered in Seguelen pit of Siguiri gold mine, Guinea, where the Siguiri mine is geo-tectonically located in the Baoulé-Mossi domain of Man Shield in West African craton. The gold deposit is hosted in low-grade metamorphic sediments of turbidites sequences which form part of the Lower Proterozoic of Birimian Super group. Three rock formations of Balato, Fatoya and Kintinian underlay the overall pits. The Siguiri gold mine is characterized by the deep weathering profile, developed over the rocks reaching 200 m below the surface in some areas and often capped by the lateritic gravel or duricrust. The rock formations at Seguelen area are characterised by strong bedding monotonously dipping towards SW and trending NW-SE. The lithology of the host rocks has strong control on the disseminated mineralisation throughout the deposit. Two domains of rock formations are clearly distinguished at Seguelen: Fatoya Formation(Ffm) domain ; and Kintinian Formation (Kfm) domain. The two domains are separated by a contact zone of 1.7 m wide parallel to bedding and characterised by the presence of quartz fragments as well as thinly sheeted shale and black shale. This contact zone is identified as disconformity. The major tectonic deformation which has affected the region is known as D2 corresponding to the Eburnean orogeny. The major D2 related structures is the regional thrust striking N-S over an area of 12 km long and 3 km wide and within which corridors all Siguiri gold Mine open pits are located. In the N-S trending structures, there is east-northeast shortening and north-northwest extension. There is pervasive hydrothermal alteration (carbonatization and sideritization) and supergene alteration in the all pits. The hydrothermal alteration attests the intensity of hydrothermal fluid-flow over the host rocks. The hydrothermal fluids flowed along the fractures and within the wall rocks through bedding plans to form numerous auriferous quartz veins bearing disseminated sulphides through chemical reaction between fluids and wall rocks, which are remarkable at Seguelen pit. Three quartz vein sets are distinguished at Seguelen: NNE-SSW quartz vein set NE-SW quartz vein set NW-SE quartz vein set The NE-SW and NNE-SSW quartz veins are often lenticular and associated with the bulk mineralisation.
- Full Text:
- Date Issued: 2015
- Authors: Beavogui, Massa
- Date: 2015
- Subjects: AngloGold Ashanti Ltd. , Gold mines and mining -- Guinea -- Siguiri (Region) , Geochemical surveys -- Guinea -- Siguiri (Region) , Geology, Structural -- Guinea -- Siguiri (Region) , Faults (Geology) -- Guinea -- Siguiri (Region) , Folds (Geology) -- Guinea -- Siguiri (Region) , Turbidites -- Guinea -- Siguiri (Region) , Metamorphism (Geology) -- Guinea -- Siguiri (Region) , Hydrothermal alteration -- Guinea -- Siguiri (Region)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5091 , http://hdl.handle.net/10962/d1019879
- Description: The present study provides the results of detailed mapping and analysis of structures encountered in Seguelen pit of Siguiri gold mine, Guinea, where the Siguiri mine is geo-tectonically located in the Baoulé-Mossi domain of Man Shield in West African craton. The gold deposit is hosted in low-grade metamorphic sediments of turbidites sequences which form part of the Lower Proterozoic of Birimian Super group. Three rock formations of Balato, Fatoya and Kintinian underlay the overall pits. The Siguiri gold mine is characterized by the deep weathering profile, developed over the rocks reaching 200 m below the surface in some areas and often capped by the lateritic gravel or duricrust. The rock formations at Seguelen area are characterised by strong bedding monotonously dipping towards SW and trending NW-SE. The lithology of the host rocks has strong control on the disseminated mineralisation throughout the deposit. Two domains of rock formations are clearly distinguished at Seguelen: Fatoya Formation(Ffm) domain ; and Kintinian Formation (Kfm) domain. The two domains are separated by a contact zone of 1.7 m wide parallel to bedding and characterised by the presence of quartz fragments as well as thinly sheeted shale and black shale. This contact zone is identified as disconformity. The major tectonic deformation which has affected the region is known as D2 corresponding to the Eburnean orogeny. The major D2 related structures is the regional thrust striking N-S over an area of 12 km long and 3 km wide and within which corridors all Siguiri gold Mine open pits are located. In the N-S trending structures, there is east-northeast shortening and north-northwest extension. There is pervasive hydrothermal alteration (carbonatization and sideritization) and supergene alteration in the all pits. The hydrothermal alteration attests the intensity of hydrothermal fluid-flow over the host rocks. The hydrothermal fluids flowed along the fractures and within the wall rocks through bedding plans to form numerous auriferous quartz veins bearing disseminated sulphides through chemical reaction between fluids and wall rocks, which are remarkable at Seguelen pit. Three quartz vein sets are distinguished at Seguelen: NNE-SSW quartz vein set NE-SW quartz vein set NW-SE quartz vein set The NE-SW and NNE-SSW quartz veins are often lenticular and associated with the bulk mineralisation.
- Full Text:
- Date Issued: 2015
The role of Stress Inducible Protein 1 (STI1) in the regulation of actin dynamics
- Authors: Beckley, Samantha Joy
- Date: 2015
- Subjects: Heat shock proteins , Molecular chaperones , Actin , Microfilament proteins , Cell migration , Adenosine triphosphatase , Metastasis
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193941 , vital:45409
- Description: Stress-inducible protein 1 (STI1) otherwise known as Hop (Hsp70/Hsp90 organising protein) is a highly conserved abundant co-chaperone of the Hsp70 and Hsp90 chaperones. STI1 acts as an adapter protein, where it regulates the transfer of protein substrates from Hsp70 to Hsp90 during the assembly of a number of chaperone-client protein complexes. The role of STI1 associating independently with non-chaperone proteins has become increasingly prominent. Recent data from colocalisation and co-sedimentation analyses in our laboratory suggested a direct interaction between STI1 and the cytoskeletal protein, actin. However, there was a lack of information on the motifs which mediated this interaction, as well as the exact role of STI1 in the regulation of cytoskeletal dynamics. Two putative actin binding motifs, DAYKKK (within the TPR2A domain) and a polyproline region (after the DP1 domain), were identified in mammalian STI1. Our data from in vitro interaction studies including surface plasmon resonance and high speed co-sedimentation assays suggested that both TPR1 and TPR2AB were required for the STI1-actin interaction, and peptides corresponding to either the DAYKKK or the polyproline motif, alone or in combination, could not block the STI1-actin interaction. Full length mSTI1 was shown to have ATPase activity and when combined with actin an increase in ATPase activity was seen. Ex vivo studies using STI1 knockdown shRNA HEK293T cells and non-targeting control shRNA HEK293T cells showed a change of F-actin morphology as well as reduction in levels of actin-binding proteins profilin, cofilin and tubulin in the STI1 knockdown cells. These data extend our understanding of the role of STI1 in regulating actin dynamics and may have implications for cell migration. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2015
- Full Text:
- Date Issued: 2015
- Authors: Beckley, Samantha Joy
- Date: 2015
- Subjects: Heat shock proteins , Molecular chaperones , Actin , Microfilament proteins , Cell migration , Adenosine triphosphatase , Metastasis
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/193941 , vital:45409
- Description: Stress-inducible protein 1 (STI1) otherwise known as Hop (Hsp70/Hsp90 organising protein) is a highly conserved abundant co-chaperone of the Hsp70 and Hsp90 chaperones. STI1 acts as an adapter protein, where it regulates the transfer of protein substrates from Hsp70 to Hsp90 during the assembly of a number of chaperone-client protein complexes. The role of STI1 associating independently with non-chaperone proteins has become increasingly prominent. Recent data from colocalisation and co-sedimentation analyses in our laboratory suggested a direct interaction between STI1 and the cytoskeletal protein, actin. However, there was a lack of information on the motifs which mediated this interaction, as well as the exact role of STI1 in the regulation of cytoskeletal dynamics. Two putative actin binding motifs, DAYKKK (within the TPR2A domain) and a polyproline region (after the DP1 domain), were identified in mammalian STI1. Our data from in vitro interaction studies including surface plasmon resonance and high speed co-sedimentation assays suggested that both TPR1 and TPR2AB were required for the STI1-actin interaction, and peptides corresponding to either the DAYKKK or the polyproline motif, alone or in combination, could not block the STI1-actin interaction. Full length mSTI1 was shown to have ATPase activity and when combined with actin an increase in ATPase activity was seen. Ex vivo studies using STI1 knockdown shRNA HEK293T cells and non-targeting control shRNA HEK293T cells showed a change of F-actin morphology as well as reduction in levels of actin-binding proteins profilin, cofilin and tubulin in the STI1 knockdown cells. These data extend our understanding of the role of STI1 in regulating actin dynamics and may have implications for cell migration. , Thesis (MSc) -- Faculty of Science, Biochemistry and Microbiology, 2015
- Full Text:
- Date Issued: 2015
Music education in the foundation phase
- Authors: Beer, Luzaan
- Date: 2015
- Subjects: Music -- Instruction and study -- South Africa , Education -- Curricula -- South Africa
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:8525 , http://hdl.handle.net/10948/d1020302
- Description: Music education is an essential aspect of education. The South African school curriculum for the Creative Arts combines dance, drama, music and the visual arts. The curriculum uses a combination of the theories of Carl Orff, Emile Jaques-Dalcroze and Zoltán Kodály. Each of these music theorists and educationists have their own distinctive approach to teaching music. This study explores the theories of music education of Carl Orff, Emile Jaques-Dalcroze and Zoltán Kodály. These theories are applied in a critical analysis of both the South African curriculum and the curriculum of New South Wales. The researcher developed music activities to address the shortcomings of both the South African curriculum and the music texts.
- Full Text:
- Date Issued: 2015
- Authors: Beer, Luzaan
- Date: 2015
- Subjects: Music -- Instruction and study -- South Africa , Education -- Curricula -- South Africa
- Language: English
- Type: Thesis , Masters , MMus
- Identifier: vital:8525 , http://hdl.handle.net/10948/d1020302
- Description: Music education is an essential aspect of education. The South African school curriculum for the Creative Arts combines dance, drama, music and the visual arts. The curriculum uses a combination of the theories of Carl Orff, Emile Jaques-Dalcroze and Zoltán Kodály. Each of these music theorists and educationists have their own distinctive approach to teaching music. This study explores the theories of music education of Carl Orff, Emile Jaques-Dalcroze and Zoltán Kodály. These theories are applied in a critical analysis of both the South African curriculum and the curriculum of New South Wales. The researcher developed music activities to address the shortcomings of both the South African curriculum and the music texts.
- Full Text:
- Date Issued: 2015
Conditions enabling or constraining the exercise of agency among new academics in higher education, conducive to the social inclusion of students
- Authors: Behari-Leak, Kasturi
- Date: 2015
- Subjects: Social integration -- South Africa , Students -- South Africa -- Social conditions , Educational change -- South Africa , College teachers -- South Africa , Education, Higher -- South Africa , Critical realism , Social realism , Agent (Philosophy)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1333 , http://hdl.handle.net/10962/d1020295
- Description: This study, which is part of a National Research Foundation project on Social Inclusion in Higher Education (HE), focuses on the exercise of agency among new academics, conducive to the social inclusion of students. Transitioning from varied entry points into higher education, new academics face numerous challenges as they embed themselves in disciplinary and institutional contexts. Given the complexity and contested nature of the current higher education landscape, new academics are especially vulnerable. Using Roy Bhaskar’s critical realism as meta-theoretical framing and Margaret Archer’s social realist theory, with its methodological focus on analytical dualism and morphogenesis, this study offers a social realist account of how new academics engage with enabling and constraining conditions at institutional, faculty, departmental and classroom levels. Through an analysis of six individual narratives of mediation, this study explicates and exemplifies the range of agential choices exercised by new academics to mediate their contested spaces. A nuanced social and critical account of the material, ideational and agential conditions in HE shows that the courses of action taken by these new academics are driven through their concerns, commitments and projects in higher education. Yet, despite the university’s espousal of embracing change, the current induction and transition of new academics is inadequate to the task of transformation in higher education. Systemic conditions in HE, conducive to critical agency and social justice, are not enabling. Bhaskar’s Seven Scalar Being, used as an analytical frame and heuristic, guides the cross-case analysis of the six narratives across seven levels of ontology. The findings highlight that, despite difficult contextual influences, the positive exercise of agency is a marked feature of new participants in HE in this study. This has immediate implications for ways in which professional and academic development, and disciplinary and departmental programmes, could create and sustain conducive conditions for the professionalisation of new academics through more sensitised practices. Using alternative research methods such as photovoice to generate its data, this doctoral study proposes that new research methodologies, located in the third space, are needed now more than ever in HE sociological research, to recognise the researcher and the research participants as independent, autonomous and causally efficacious beings. To this end, this study includes a Chapter Zero, which captures the narrative of the doctoral scholar as researcher, who, shaped and influenced by established doctoral practices and traditions in the field, exercises her own doctoral agency in particular ways.
- Full Text:
- Date Issued: 2015
- Authors: Behari-Leak, Kasturi
- Date: 2015
- Subjects: Social integration -- South Africa , Students -- South Africa -- Social conditions , Educational change -- South Africa , College teachers -- South Africa , Education, Higher -- South Africa , Critical realism , Social realism , Agent (Philosophy)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1333 , http://hdl.handle.net/10962/d1020295
- Description: This study, which is part of a National Research Foundation project on Social Inclusion in Higher Education (HE), focuses on the exercise of agency among new academics, conducive to the social inclusion of students. Transitioning from varied entry points into higher education, new academics face numerous challenges as they embed themselves in disciplinary and institutional contexts. Given the complexity and contested nature of the current higher education landscape, new academics are especially vulnerable. Using Roy Bhaskar’s critical realism as meta-theoretical framing and Margaret Archer’s social realist theory, with its methodological focus on analytical dualism and morphogenesis, this study offers a social realist account of how new academics engage with enabling and constraining conditions at institutional, faculty, departmental and classroom levels. Through an analysis of six individual narratives of mediation, this study explicates and exemplifies the range of agential choices exercised by new academics to mediate their contested spaces. A nuanced social and critical account of the material, ideational and agential conditions in HE shows that the courses of action taken by these new academics are driven through their concerns, commitments and projects in higher education. Yet, despite the university’s espousal of embracing change, the current induction and transition of new academics is inadequate to the task of transformation in higher education. Systemic conditions in HE, conducive to critical agency and social justice, are not enabling. Bhaskar’s Seven Scalar Being, used as an analytical frame and heuristic, guides the cross-case analysis of the six narratives across seven levels of ontology. The findings highlight that, despite difficult contextual influences, the positive exercise of agency is a marked feature of new participants in HE in this study. This has immediate implications for ways in which professional and academic development, and disciplinary and departmental programmes, could create and sustain conducive conditions for the professionalisation of new academics through more sensitised practices. Using alternative research methods such as photovoice to generate its data, this doctoral study proposes that new research methodologies, located in the third space, are needed now more than ever in HE sociological research, to recognise the researcher and the research participants as independent, autonomous and causally efficacious beings. To this end, this study includes a Chapter Zero, which captures the narrative of the doctoral scholar as researcher, who, shaped and influenced by established doctoral practices and traditions in the field, exercises her own doctoral agency in particular ways.
- Full Text:
- Date Issued: 2015
An indirectly controlled high-speed servo valve using piezo actuators
- Authors: Behre, Leander
- Date: 2015
- Subjects: Piezoelectric materials Piezoelectric devices -- Materials , Internal combustion engines Mechatronics Automation
- Language: English
- Type: Thesis , Masters , MEng
- Identifier: http://hdl.handle.net/10948/50099 , vital:42040
- Description: Since the exhaust emissions legislation for motor vehicles with combustion engines is complicating the manufacturing of environmental yet powerful engines more than ever, automobile manufacturers have approached this challenge by means of downsizing, hybridization of combustion and electric engines and variable valve opening times. In these cases conventional, mechanical valve trains are still used. The subject of this master thesis is the development of a mechatronic control unit as replacement for the camshaft driven valve train of common combustion engines. The system’s aim is a contribution to the progression of the development of modern combustion engines satisfying current demands in terms of economy and efficiency. The developed system is based on the “Full Variable Valve Train” project, founded at the “Institute of Vehicle Construction Wolfsburg” at the “Ostfalia University of Applied Sciences”. An indirectly controlled high speed servo valve that is actuated by a piezoelectric actuator and pressurized hydraulic fluid is being developed. The overall aim is to obtain advantages from a control engineering perspective, being able to reduce the size of the used piezo actuator and hence solve the packaging and regulation issues of the overall system. After manufacturing and improvement activities, a system could be developed that allows a variable control of the engine valve movement. The best results are achieved using a rectangular function for the engine valve actuator. The system allows engine valve operation independent from the crankshaft position and shows the potential to generate higher engine torque and power output while decreasing fuel consumption and emissions at the same time.
- Full Text:
- Date Issued: 2015
- Authors: Behre, Leander
- Date: 2015
- Subjects: Piezoelectric materials Piezoelectric devices -- Materials , Internal combustion engines Mechatronics Automation
- Language: English
- Type: Thesis , Masters , MEng
- Identifier: http://hdl.handle.net/10948/50099 , vital:42040
- Description: Since the exhaust emissions legislation for motor vehicles with combustion engines is complicating the manufacturing of environmental yet powerful engines more than ever, automobile manufacturers have approached this challenge by means of downsizing, hybridization of combustion and electric engines and variable valve opening times. In these cases conventional, mechanical valve trains are still used. The subject of this master thesis is the development of a mechatronic control unit as replacement for the camshaft driven valve train of common combustion engines. The system’s aim is a contribution to the progression of the development of modern combustion engines satisfying current demands in terms of economy and efficiency. The developed system is based on the “Full Variable Valve Train” project, founded at the “Institute of Vehicle Construction Wolfsburg” at the “Ostfalia University of Applied Sciences”. An indirectly controlled high speed servo valve that is actuated by a piezoelectric actuator and pressurized hydraulic fluid is being developed. The overall aim is to obtain advantages from a control engineering perspective, being able to reduce the size of the used piezo actuator and hence solve the packaging and regulation issues of the overall system. After manufacturing and improvement activities, a system could be developed that allows a variable control of the engine valve movement. The best results are achieved using a rectangular function for the engine valve actuator. The system allows engine valve operation independent from the crankshaft position and shows the potential to generate higher engine torque and power output while decreasing fuel consumption and emissions at the same time.
- Full Text:
- Date Issued: 2015
The antifungal activity of an aqueous Tulbaghia violacea plant extract against Aspergillus flavus
- Authors: Belewa, Xoliswa Vuyokazi
- Date: 2015
- Subjects: Medicinal plants , Antifungal agents , Fungi -- Biotechnology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/5858 , vital:21001
- Description: Phytochemical analysis of both HEA1 and the crude plant extract showed the presence of phenolics, tannins and saponins. Saponins were the predominant secondary metabolites and were mostly abundant in the plant extract and to a lesser extent in the active compound. Steroidal saponins, tannins and phenolics were also detected in the plant extract, but only the phenolics were detected in the active compound. The results of the phytochemical analysis showed that those compounds that were not present in the active compound could be removed from the crude extract during the TLC purification process. Investigation on the mechanism of action of the crude plant extract on the sterol production by A. flavus showed that the plant extract affected ergosterol biosynthesis by causing an accumulation of oxidosqualene in the ergosterol biosynthetic pathway resulting in a decline in ergosterol production. An oscillatory response in lanosterol production was observed in the presence of the plant extract, which may be an adaptation mechanism of A. flavus to unfavourable conditions and compensation for the loss of enzyme activity which may have occurred as a result of the accumulation of oxidosqualene. The antifungal activity of the plant extract on ergosterol production by A. flavus may also be due to saponins which target the cell membrane and ergosterol production in fungi. The effect of the plant extract on the fungal cell wall of A. flavus also showed that the plant extract caused a decline in β-(1, 3) glucan production by inhibiting β-glucan synthase. The plant extract also affected the chitin synthesis pathway of A. flavus, by causing a decline in chitin production, which was due to the inhibition of chitin synthase. Investigation of chitinase production using 4MU substrates showed that the plant extract caused an accumulation of chitobioses, by activating chitobiosidases and endochitinases. A decline in N-acetylglucosaminidase activity in the presence of the plant extract was observed and this prevented the formation of N-acetylglucosamine. The accumulation of chitobiosidase and endochitinase may be as a result of autolysis that may be triggered by A. flavus as a survival mechanism in the presence of the plant extract and as a compensatory mechanism for the loss of β-glucans and chitin. The antifungal effect of the plant extract on various components of the cell wall of A. flavus, makes T. violacea aqueous plant extract an ideal chemotherapeutic agent against both human and plant pathogens of Aspergillus. The broad spectrum of antifungal activity of T. violacea against A. flavus also eliminates any chances of the fungus developing resistance towards it and would make it a candidate for use as a potential antifungal agent. Further identification and possible chemical synthesis is needed to shed light on the safety and efficacy of the active compound for further development as a chemotherapeutic agent.
- Full Text:
- Date Issued: 2015
- Authors: Belewa, Xoliswa Vuyokazi
- Date: 2015
- Subjects: Medicinal plants , Antifungal agents , Fungi -- Biotechnology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/5858 , vital:21001
- Description: Phytochemical analysis of both HEA1 and the crude plant extract showed the presence of phenolics, tannins and saponins. Saponins were the predominant secondary metabolites and were mostly abundant in the plant extract and to a lesser extent in the active compound. Steroidal saponins, tannins and phenolics were also detected in the plant extract, but only the phenolics were detected in the active compound. The results of the phytochemical analysis showed that those compounds that were not present in the active compound could be removed from the crude extract during the TLC purification process. Investigation on the mechanism of action of the crude plant extract on the sterol production by A. flavus showed that the plant extract affected ergosterol biosynthesis by causing an accumulation of oxidosqualene in the ergosterol biosynthetic pathway resulting in a decline in ergosterol production. An oscillatory response in lanosterol production was observed in the presence of the plant extract, which may be an adaptation mechanism of A. flavus to unfavourable conditions and compensation for the loss of enzyme activity which may have occurred as a result of the accumulation of oxidosqualene. The antifungal activity of the plant extract on ergosterol production by A. flavus may also be due to saponins which target the cell membrane and ergosterol production in fungi. The effect of the plant extract on the fungal cell wall of A. flavus also showed that the plant extract caused a decline in β-(1, 3) glucan production by inhibiting β-glucan synthase. The plant extract also affected the chitin synthesis pathway of A. flavus, by causing a decline in chitin production, which was due to the inhibition of chitin synthase. Investigation of chitinase production using 4MU substrates showed that the plant extract caused an accumulation of chitobioses, by activating chitobiosidases and endochitinases. A decline in N-acetylglucosaminidase activity in the presence of the plant extract was observed and this prevented the formation of N-acetylglucosamine. The accumulation of chitobiosidase and endochitinase may be as a result of autolysis that may be triggered by A. flavus as a survival mechanism in the presence of the plant extract and as a compensatory mechanism for the loss of β-glucans and chitin. The antifungal effect of the plant extract on various components of the cell wall of A. flavus, makes T. violacea aqueous plant extract an ideal chemotherapeutic agent against both human and plant pathogens of Aspergillus. The broad spectrum of antifungal activity of T. violacea against A. flavus also eliminates any chances of the fungus developing resistance towards it and would make it a candidate for use as a potential antifungal agent. Further identification and possible chemical synthesis is needed to shed light on the safety and efficacy of the active compound for further development as a chemotherapeutic agent.
- Full Text:
- Date Issued: 2015
Articulating the nature of clinical nurse specialist practice
- Authors: Bell, Janet Deanne
- Date: 2015
- Subjects: Nurse practitioners , Intensive care nursing
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10057 , http://hdl.handle.net/10948/d1018623
- Description: Critical care nursing is a clinical specialist nursing practice discipline. The critical care nurse provides a constant presence in the care of a critically ill patient. She/he creates a thread of continuity in care through the myriad of other health care professionals and activities that form part of a patient’s stay in the critical care environment (World Federation of Critical Care Nurses [WFCCN], 2007). During conversations with people who have had intimate experience of the critical care environment, they have offered anecdotes that describe their interaction with critical care nurses who they perceive to be different from and better than other critical care nurses they encountered. Despite having met common professional requirements to be registered as a clinical specialist nurse, these distinctive, unique abilities that seem to be influential in meeting the complex needs and expectations of critically ill patients, their significant others as well as nursing and medical colleagues, are not displayed by all critical care nurses. While students of accredited postgraduate nursing programmes are required to advance their nursing knowledge and skill competence, many students do not seem to develop other, perhaps more tacit, qualities that utilisers characterise in their anecdotes of ‘different and better’ nursing practice. The overarching research question guiding this study was how can ‘different and better’ critical care nursing practice as recognised by a utiliser be explained? The purpose of this study was to develop an understanding of the qualities that those people who use critical care nursing practice recognise as ‘different and better’ to the norm of nursing practice they encounter in this discipline. The participant sample included patients’ significant others, nursing colleagues and medical colleagues of critical care nurses, collectively identified as utilisers. The stated aim of this work was to construct a grounded theory to elucidate an understanding of the qualities that a utiliser of critical care nursing recognises as ‘different and better’ critical care nursing practice in order to enhance the teaching and learning encounters between nurse educators and postgraduate students in learning programmes aiming to develop clinical specialist nurses. The method processes of grounded theory are designed to reveal and confirm concepts from within the data as well as the connections between these concepts, supporting the researcher in crafting a substantive theory that is definitively grounded in the participants’ views and stories (Streubert & Carpenter, 2011: 123, 128-129). Two data collection tools were employed in this study, namely in-depth unstructured individual interviews and naïve sketch. Constant comparative analysis, memo-writing, theoretical sampling, theoretical sensitivity and theoretical saturation as fundamental methods of data generation in grounded theory were applied. The study unfolded through three broad parts, namely: Forming & shaping this grounded theory through exploration and co-creation; Assimilating & situating this grounded theory through understanding and enfolding; Reflecting on this grounded theory through contemplating and reconnecting. The outcome of the first part of the study was my initial proposition of a grounded theory co-created in the interactions between the participants and myself. This was then challenged, developed and assimilated through a focussed literature review through the second part of the study. Through these two parts of this study, an inductively derived explanation was formed and shaped to produce an assimilated and situated substantive grounded theory named Being at Ease. This grounded theory articulates how ‘better and different’ nursing is recognised from the point of view of those who use the nursing ability of critical care nurses through the core concern ‘being at ease’ and its four categories ‘knowing self’, ‘skilled being’, connecting with intention’ and’ anchoring’. The final part of this study unfolded in my reflections on what this grounded theory had revealed about nurses and elements of nursing practice that are important to a utiliser in recognising ‘different and better’ critical care nursing. I suggest that as nurses we need to develop a language that enables us to reveal with clarity these intangible and tacit elements recognised within the being and doing of ‘different and better’ nursing. I reflected on the pivotal space of influence a teacher has with a student, and on how the elements essential in being and doing ‘different and better’ nursing need to be evident in her/his own ways of being a teacher of nursing. Teaching and learning encounters may be enhanced through drawing what this theory has shown as necessary elements that shape ‘different and better’ nurses through the moments of influence a teacher has in each encounter with a student.
- Full Text:
- Date Issued: 2015
- Authors: Bell, Janet Deanne
- Date: 2015
- Subjects: Nurse practitioners , Intensive care nursing
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10057 , http://hdl.handle.net/10948/d1018623
- Description: Critical care nursing is a clinical specialist nursing practice discipline. The critical care nurse provides a constant presence in the care of a critically ill patient. She/he creates a thread of continuity in care through the myriad of other health care professionals and activities that form part of a patient’s stay in the critical care environment (World Federation of Critical Care Nurses [WFCCN], 2007). During conversations with people who have had intimate experience of the critical care environment, they have offered anecdotes that describe their interaction with critical care nurses who they perceive to be different from and better than other critical care nurses they encountered. Despite having met common professional requirements to be registered as a clinical specialist nurse, these distinctive, unique abilities that seem to be influential in meeting the complex needs and expectations of critically ill patients, their significant others as well as nursing and medical colleagues, are not displayed by all critical care nurses. While students of accredited postgraduate nursing programmes are required to advance their nursing knowledge and skill competence, many students do not seem to develop other, perhaps more tacit, qualities that utilisers characterise in their anecdotes of ‘different and better’ nursing practice. The overarching research question guiding this study was how can ‘different and better’ critical care nursing practice as recognised by a utiliser be explained? The purpose of this study was to develop an understanding of the qualities that those people who use critical care nursing practice recognise as ‘different and better’ to the norm of nursing practice they encounter in this discipline. The participant sample included patients’ significant others, nursing colleagues and medical colleagues of critical care nurses, collectively identified as utilisers. The stated aim of this work was to construct a grounded theory to elucidate an understanding of the qualities that a utiliser of critical care nursing recognises as ‘different and better’ critical care nursing practice in order to enhance the teaching and learning encounters between nurse educators and postgraduate students in learning programmes aiming to develop clinical specialist nurses. The method processes of grounded theory are designed to reveal and confirm concepts from within the data as well as the connections between these concepts, supporting the researcher in crafting a substantive theory that is definitively grounded in the participants’ views and stories (Streubert & Carpenter, 2011: 123, 128-129). Two data collection tools were employed in this study, namely in-depth unstructured individual interviews and naïve sketch. Constant comparative analysis, memo-writing, theoretical sampling, theoretical sensitivity and theoretical saturation as fundamental methods of data generation in grounded theory were applied. The study unfolded through three broad parts, namely: Forming & shaping this grounded theory through exploration and co-creation; Assimilating & situating this grounded theory through understanding and enfolding; Reflecting on this grounded theory through contemplating and reconnecting. The outcome of the first part of the study was my initial proposition of a grounded theory co-created in the interactions between the participants and myself. This was then challenged, developed and assimilated through a focussed literature review through the second part of the study. Through these two parts of this study, an inductively derived explanation was formed and shaped to produce an assimilated and situated substantive grounded theory named Being at Ease. This grounded theory articulates how ‘better and different’ nursing is recognised from the point of view of those who use the nursing ability of critical care nurses through the core concern ‘being at ease’ and its four categories ‘knowing self’, ‘skilled being’, connecting with intention’ and’ anchoring’. The final part of this study unfolded in my reflections on what this grounded theory had revealed about nurses and elements of nursing practice that are important to a utiliser in recognising ‘different and better’ critical care nursing. I suggest that as nurses we need to develop a language that enables us to reveal with clarity these intangible and tacit elements recognised within the being and doing of ‘different and better’ nursing. I reflected on the pivotal space of influence a teacher has with a student, and on how the elements essential in being and doing ‘different and better’ nursing need to be evident in her/his own ways of being a teacher of nursing. Teaching and learning encounters may be enhanced through drawing what this theory has shown as necessary elements that shape ‘different and better’ nurses through the moments of influence a teacher has in each encounter with a student.
- Full Text:
- Date Issued: 2015
Entrepreneurial intention among Rhodes University undergraduate students
- Authors: Bell, Jonathan Andrew
- Date: 2015
- Subjects: Rhodes University -- Undergraduates , Entrepreneurship -- South Africa -- Grahamstown , Social cognitive theory , Intention , Attitude (Psychology) , Influence (Psychology) , South Africa -- Economic conditions -- 1991-
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3267 , http://hdl.handle.net/10962/d1020011
- Description: The entrepreneurial intentions of university students are important factors to consider when developing entrepreneurship offerings at tertiary level institutions. This research study reports on pertinent findings from a study which set out to determine Rhodes university undergraduate students‟ entrepreneurial intentions and their pull and push factors that have brought them to the decision to become entrepreneurs. A survey, using a 43 question structured web-based instrument was used to capture the responses from undergraduate students across different departments at Rhodes University, Grahamstown. Key findings suggest that few undergraduate students intend to enter into an entrepreneurship career immediately after completion of their studies, whereas many of the respondents were more interested in doing so five years after graduation. The vast majority of students were satisfied without having formal entrepreneurial education and factors such as previous employment in entrepreneurial activities, and family influence had a statistical significant relationship with entrepreneurial intention.
- Full Text:
- Date Issued: 2015
- Authors: Bell, Jonathan Andrew
- Date: 2015
- Subjects: Rhodes University -- Undergraduates , Entrepreneurship -- South Africa -- Grahamstown , Social cognitive theory , Intention , Attitude (Psychology) , Influence (Psychology) , South Africa -- Economic conditions -- 1991-
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3267 , http://hdl.handle.net/10962/d1020011
- Description: The entrepreneurial intentions of university students are important factors to consider when developing entrepreneurship offerings at tertiary level institutions. This research study reports on pertinent findings from a study which set out to determine Rhodes university undergraduate students‟ entrepreneurial intentions and their pull and push factors that have brought them to the decision to become entrepreneurs. A survey, using a 43 question structured web-based instrument was used to capture the responses from undergraduate students across different departments at Rhodes University, Grahamstown. Key findings suggest that few undergraduate students intend to enter into an entrepreneurship career immediately after completion of their studies, whereas many of the respondents were more interested in doing so five years after graduation. The vast majority of students were satisfied without having formal entrepreneurial education and factors such as previous employment in entrepreneurial activities, and family influence had a statistical significant relationship with entrepreneurial intention.
- Full Text:
- Date Issued: 2015
Drivers and consequences of residents' satisfaction with off-campus student housing in South-South, Nigeria
- Authors: Bella-Omunagbe, Ojo Cyprain
- Date: 2015
- Subjects: Student housing -- Nigeria , Housing -- Resident satisfaction , Residence and education , Universities and colleges -- Nigeria -- Administration
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9720 , http://hdl.handle.net/10948/d1021198
- Description: The student housing system worldwide and South-South Nigeria in particular has witnessed an unprecedented transformation, such that private off-campus student housing facilities (SHFs) are now the primary source of accommodation for students in tertiary institutions. A considerable gap exists between the supply and demand for on-campus student housing and the quest to fill this gap has stimulated the creation of a significant student housing market in the areas where these tertiary institutions are located. The prospect for economic investments in the student housing sector is high and private investors are involved in the provision and management of offcampus student housing. The main consequence of this practice in South-South, Nigeria is the delivery of low-quality buildings that are not able to meet the needs and expectations of residents. SHFs that are constructed without due regard to residents needs are characterised by dissatisfaction with attributes of housing and low investment performance. The implication is that residence users are often not satisfied with the attributes of the residential environment that are provided; thus their behaviours often impose some consequences on investors gains and objectives.Therefore, understanding the dynamics among attributes that are important to students, that give the required satisfaction, and the impact of the availability or lack-of on behaviour such as loyalty, willingness to pay for attributes and word of mouth behaviour are critical to profitability. Most often, the relationship among these attributes are treated as linear and symmetrical with the assumed implication that better attributes produce improved behaviours. However, this may not always be the case. This approach is rarely addressed and is little understood in student housing studies. Therefore, the aim of this study was to identify student housing attributes that act as drivers of resident atisfaction and the consequences/effects of these drivers on student behaviour in order to determine appropriate measures that could be used to develop, maintain and upgrade student accommodation. The methodology of the study included an extensive literature review and a field study conducted to obtain the perceptions of students in seven tertiary institutions located in South-South, Nigeria. The main task was to define attributes of student housing facilities based on the symmetric and asymmetric impact of the performance of attributes on satisfaction with residence. The Kano model and importance-performance analysis (IPA) were used to establish sets of criteria that could be used to prioritise attributes that are required in student housing for optimal investor gains. Analysis of the findings lead to the conclusions that different degrees of behaviour were associated to the perception of importance that is attached to attributes by residents and the satisfaction that is derived from the use of such attributes. The implication of the conclusions is that to meet users satisfaction needs, varied improvement strategies are required for different attributes in order to maximise the use of resources for maximum gains. The recommendations for investors in SHFs include among others to segment the SHFs market based on demographic characteristics, prioritise and provide only attributes that add-value to identified groups. Emphasis should also be placed on providing attributes that are not only satisfactory, but with capacity to improve loyalty/retention, willingness to pay and positive word of mouth behaviour. It is also recommended that the local authority should improve critical attributes that are deemed to be outside the scope of the investors.
- Full Text:
- Date Issued: 2015
- Authors: Bella-Omunagbe, Ojo Cyprain
- Date: 2015
- Subjects: Student housing -- Nigeria , Housing -- Resident satisfaction , Residence and education , Universities and colleges -- Nigeria -- Administration
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9720 , http://hdl.handle.net/10948/d1021198
- Description: The student housing system worldwide and South-South Nigeria in particular has witnessed an unprecedented transformation, such that private off-campus student housing facilities (SHFs) are now the primary source of accommodation for students in tertiary institutions. A considerable gap exists between the supply and demand for on-campus student housing and the quest to fill this gap has stimulated the creation of a significant student housing market in the areas where these tertiary institutions are located. The prospect for economic investments in the student housing sector is high and private investors are involved in the provision and management of offcampus student housing. The main consequence of this practice in South-South, Nigeria is the delivery of low-quality buildings that are not able to meet the needs and expectations of residents. SHFs that are constructed without due regard to residents needs are characterised by dissatisfaction with attributes of housing and low investment performance. The implication is that residence users are often not satisfied with the attributes of the residential environment that are provided; thus their behaviours often impose some consequences on investors gains and objectives.Therefore, understanding the dynamics among attributes that are important to students, that give the required satisfaction, and the impact of the availability or lack-of on behaviour such as loyalty, willingness to pay for attributes and word of mouth behaviour are critical to profitability. Most often, the relationship among these attributes are treated as linear and symmetrical with the assumed implication that better attributes produce improved behaviours. However, this may not always be the case. This approach is rarely addressed and is little understood in student housing studies. Therefore, the aim of this study was to identify student housing attributes that act as drivers of resident atisfaction and the consequences/effects of these drivers on student behaviour in order to determine appropriate measures that could be used to develop, maintain and upgrade student accommodation. The methodology of the study included an extensive literature review and a field study conducted to obtain the perceptions of students in seven tertiary institutions located in South-South, Nigeria. The main task was to define attributes of student housing facilities based on the symmetric and asymmetric impact of the performance of attributes on satisfaction with residence. The Kano model and importance-performance analysis (IPA) were used to establish sets of criteria that could be used to prioritise attributes that are required in student housing for optimal investor gains. Analysis of the findings lead to the conclusions that different degrees of behaviour were associated to the perception of importance that is attached to attributes by residents and the satisfaction that is derived from the use of such attributes. The implication of the conclusions is that to meet users satisfaction needs, varied improvement strategies are required for different attributes in order to maximise the use of resources for maximum gains. The recommendations for investors in SHFs include among others to segment the SHFs market based on demographic characteristics, prioritise and provide only attributes that add-value to identified groups. Emphasis should also be placed on providing attributes that are not only satisfactory, but with capacity to improve loyalty/retention, willingness to pay and positive word of mouth behaviour. It is also recommended that the local authority should improve critical attributes that are deemed to be outside the scope of the investors.
- Full Text:
- Date Issued: 2015
Evaluation of teaching and courses: reframing traditional understandings and practices
- Authors: Belluigi, Dina Z
- Date: 2015
- Language: English
- Type: Book , text
- Identifier: http://hdl.handle.net/10962/59546 , vital:27625
- Description: This anthology outlines case studies which have emerged from an approach to evaluation which enables individual academics to practice a degree of autonomy in how they determine their own evaluation agendas, methods and approaches. This has enabled individual cases of both rigour and creativity when it comes to the collection of data and generation of feed- back on their teaching and/or courses, particularly in relation to transforming curricula responsively; enabling student voice and increasing student ownership; and creating spaces for practices to be challenged. The purpose of the case studies is pedagogic and to illustrate a range of practices and principles. For the sake of clarity some of the details have been omitted or slightly changed.
- Full Text:
- Date Issued: 2015
- Authors: Belluigi, Dina Z
- Date: 2015
- Language: English
- Type: Book , text
- Identifier: http://hdl.handle.net/10962/59546 , vital:27625
- Description: This anthology outlines case studies which have emerged from an approach to evaluation which enables individual academics to practice a degree of autonomy in how they determine their own evaluation agendas, methods and approaches. This has enabled individual cases of both rigour and creativity when it comes to the collection of data and generation of feed- back on their teaching and/or courses, particularly in relation to transforming curricula responsively; enabling student voice and increasing student ownership; and creating spaces for practices to be challenged. The purpose of the case studies is pedagogic and to illustrate a range of practices and principles. For the sake of clarity some of the details have been omitted or slightly changed.
- Full Text:
- Date Issued: 2015
Spatial and temporal variations in trophic connectivity within an estuarine environment : benthic-pelagic and terrestrial-aquatic linkages via invertebrates and fishes
- Authors: Bergamino Roman, Leandro
- Date: 2015
- Subjects: Estuarine ecology -- South Africa , Marine invertebrates -- South Africa -- Ecology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5921 , http://hdl.handle.net/10962/d1017799
- Description: Estuarine ecosystems are among the most biologically productive areas and they provide important ecosystem services such as erosion control, habitat and refugia for several species. These environments are characterized by the presence of a variety of organic matter sources due to their transitional position between rivers and the sea. The biotic compositions can undergo spatial and seasonal changes along the estuary due to the spatial and temporal fluctuations of environmental factors such as salinity, temperature and seston loads. Therefore, the different combinations of biotic and abiotic factors make each estuary a unique ecosystem. Because of this spatial and temporal complexity, the understanding of estuarine food web structure and which factors affect the trophic relationships within the ecosystem through space and time represent challenging tasks. Furthermore, estuaries are under an increasing number of anthropogenic perturbations because of the growing concentration of human populations in coastal areas. Knowledge of ecosystem structure and functioning is essential for effective conservation and management planning of coastal areas.In this dissertation, I combine the utilization of biological tracers to examine spatial and temporal variability in the food web structure within a small temperate and microtidal estuary located in South Africa. To this end, fatty acid profiles and stable isotope signatures were measured in several primary organic matter sources and consumers (including zooplankton, fishes and benthic invertebrates) during four consecutive seasons and in three different estuarine regions: upper, middle, and lower reaches. The three reaches had distinct habitat features of vegetation type and morphology, and in particular the lower reaches were colonized by the marsh grass Spartina maritima. Isotopic mixing models were used to estimate the relative contribution of each food source to the diets of invertebrates and fishes within the estuarine food web. The isotopic and fatty acid data showed similar results. In general, the lower reaches of the estuary were characterized by a higher deposition and assimilation by brachyuran crabs of carbon derived from marsh grass detritus, whiletowards the upper reaches a mixture of microphytobenthos and particulate organic matter (phytoplankton and detritus) was deposited and sustained the pelagic and benthic fauna. The highest deposition and assimilation of marsh grass detritus in the lower reaches of the estuary occurred during periods of low freshwater discharge (autumn and winter). In the upper reaches, microphytobenthos and suspended particulate organic matter were dominant basal food resources for the food web during all seasons. These results indicated that benthic consumers incorporated mainly local carbon sources from their local habitat.To clarify isotopic and fatty acid patterns I examined the trophic behaviour of the sesarmid crab Sesarma catenata through laboratory feeding experiments. Results from these experiments validated that decomposed leaves of riparian trees and the salt marsh plant S. maritima were the preferred food of the sesarmid crabs, potentially due to high bacterial loads. The remaining leaf material not assimilated by crabs, together with faecal material, are likely important subsidies for adjacent environments, hence representing an important energy pathway involving the microbial food chain. Furthermore, this dissertation showed the importance of mobile top predators as vectors energetically connecting distinct food chains within the estuary (i.e. littoral, benthic and pelagic). I concluded that a combination of physical (i.e. patterns of freshwater discharge and estuary morphology) and biological factors (i.e. organism feeding behaviour, mobility, primary productivity, the local vegetation type) influence the pattern of dominant primary organic matter sources, and therefore the food web structure along the estuarine environment. In particular, marsh grass detritus contributed substantially to the diets of estuarine fauna during periods of low freshwater discharge. Given the importance of the salt marsh habitat in providing trophic resources, it is important to preserve this environment to sustain the natural biota and ecosystem functioning.
- Full Text:
- Date Issued: 2015
- Authors: Bergamino Roman, Leandro
- Date: 2015
- Subjects: Estuarine ecology -- South Africa , Marine invertebrates -- South Africa -- Ecology
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5921 , http://hdl.handle.net/10962/d1017799
- Description: Estuarine ecosystems are among the most biologically productive areas and they provide important ecosystem services such as erosion control, habitat and refugia for several species. These environments are characterized by the presence of a variety of organic matter sources due to their transitional position between rivers and the sea. The biotic compositions can undergo spatial and seasonal changes along the estuary due to the spatial and temporal fluctuations of environmental factors such as salinity, temperature and seston loads. Therefore, the different combinations of biotic and abiotic factors make each estuary a unique ecosystem. Because of this spatial and temporal complexity, the understanding of estuarine food web structure and which factors affect the trophic relationships within the ecosystem through space and time represent challenging tasks. Furthermore, estuaries are under an increasing number of anthropogenic perturbations because of the growing concentration of human populations in coastal areas. Knowledge of ecosystem structure and functioning is essential for effective conservation and management planning of coastal areas.In this dissertation, I combine the utilization of biological tracers to examine spatial and temporal variability in the food web structure within a small temperate and microtidal estuary located in South Africa. To this end, fatty acid profiles and stable isotope signatures were measured in several primary organic matter sources and consumers (including zooplankton, fishes and benthic invertebrates) during four consecutive seasons and in three different estuarine regions: upper, middle, and lower reaches. The three reaches had distinct habitat features of vegetation type and morphology, and in particular the lower reaches were colonized by the marsh grass Spartina maritima. Isotopic mixing models were used to estimate the relative contribution of each food source to the diets of invertebrates and fishes within the estuarine food web. The isotopic and fatty acid data showed similar results. In general, the lower reaches of the estuary were characterized by a higher deposition and assimilation by brachyuran crabs of carbon derived from marsh grass detritus, whiletowards the upper reaches a mixture of microphytobenthos and particulate organic matter (phytoplankton and detritus) was deposited and sustained the pelagic and benthic fauna. The highest deposition and assimilation of marsh grass detritus in the lower reaches of the estuary occurred during periods of low freshwater discharge (autumn and winter). In the upper reaches, microphytobenthos and suspended particulate organic matter were dominant basal food resources for the food web during all seasons. These results indicated that benthic consumers incorporated mainly local carbon sources from their local habitat.To clarify isotopic and fatty acid patterns I examined the trophic behaviour of the sesarmid crab Sesarma catenata through laboratory feeding experiments. Results from these experiments validated that decomposed leaves of riparian trees and the salt marsh plant S. maritima were the preferred food of the sesarmid crabs, potentially due to high bacterial loads. The remaining leaf material not assimilated by crabs, together with faecal material, are likely important subsidies for adjacent environments, hence representing an important energy pathway involving the microbial food chain. Furthermore, this dissertation showed the importance of mobile top predators as vectors energetically connecting distinct food chains within the estuary (i.e. littoral, benthic and pelagic). I concluded that a combination of physical (i.e. patterns of freshwater discharge and estuary morphology) and biological factors (i.e. organism feeding behaviour, mobility, primary productivity, the local vegetation type) influence the pattern of dominant primary organic matter sources, and therefore the food web structure along the estuarine environment. In particular, marsh grass detritus contributed substantially to the diets of estuarine fauna during periods of low freshwater discharge. Given the importance of the salt marsh habitat in providing trophic resources, it is important to preserve this environment to sustain the natural biota and ecosystem functioning.
- Full Text:
- Date Issued: 2015
Androcentrism and misogyny in late twentieth century rock music
- Authors: Berkland, Darren Gary
- Date: 2015
- Subjects: Music -- Social aspects , Gender identity in music , Music -- Performance -- Psychological aspects , Emotions in music , Rock musicians
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8440 , http://hdl.handle.net/10948/d1021199
- Description: Judith Butler’s writings on gender ostensibly changed the way gender is considered with regard to an individual’s subjectivity. Her writings expressed a discursive parameter that changed the theoretical standpoint of gender from that of performance, to that of performativity. In short, the notion of gender became understood as a power mechanism operating within society that compels individuals along the heteronormal binary tracts of male or female, man or woman. Within the strata of popular culture, this binarism is seemingly ritualized and repeated, incessantly. This treatise examines how rock music, as a popular and widespread mode of popular music, exemplifies gender binarism through a notable ndrocentrism. The research will examine how gender performativity operates within the taxonomy of rock music, and how the message communicated by rock music becomes translated into a listener’s subjectivity.
- Full Text:
- Date Issued: 2015
- Authors: Berkland, Darren Gary
- Date: 2015
- Subjects: Music -- Social aspects , Gender identity in music , Music -- Performance -- Psychological aspects , Emotions in music , Rock musicians
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:8440 , http://hdl.handle.net/10948/d1021199
- Description: Judith Butler’s writings on gender ostensibly changed the way gender is considered with regard to an individual’s subjectivity. Her writings expressed a discursive parameter that changed the theoretical standpoint of gender from that of performance, to that of performativity. In short, the notion of gender became understood as a power mechanism operating within society that compels individuals along the heteronormal binary tracts of male or female, man or woman. Within the strata of popular culture, this binarism is seemingly ritualized and repeated, incessantly. This treatise examines how rock music, as a popular and widespread mode of popular music, exemplifies gender binarism through a notable ndrocentrism. The research will examine how gender performativity operates within the taxonomy of rock music, and how the message communicated by rock music becomes translated into a listener’s subjectivity.
- Full Text:
- Date Issued: 2015
An analysis of the risk exposure of adopting IPV6 in enterprise networks
- Authors: Berko, Istvan Sandor
- Date: 2015
- Subjects: International Workshop on Deploying the Future Infrastructure , Computer networks , Computer networks -- Security measures , Computer network protocols
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4722 , http://hdl.handle.net/10962/d1018918
- Description: The IPv6 increased address pool presents changes in resource impact to the Enterprise that, if not adequately addressed, can change risks that are locally significant in IPv4 to risks that can impact the Enterprise in its entirety. The expected conclusion is that the IPv6 environment will impose significant changes in the Enterprise environment - which may negatively impact organisational security if the IPv6 nuances are not adequately addressed. This thesis reviews the risks related to the operation of enterprise networks with the introduction of IPv6. The global trends are discussed to provide insight and background to the IPv6 research space. Analysing the current state of readiness in enterprise networks, quantifies the value of developing this thesis. The base controls that should be deployed in enterprise networks to prevent the abuse of IPv6 through tunnelling and the protection of the enterprise access layer are discussed. A series of case studies are presented which identify and analyse the impact of certain changes in the IPv6 protocol on the enterprise networks. The case studies also identify mitigation techniques to reduce risk.
- Full Text:
- Date Issued: 2015
- Authors: Berko, Istvan Sandor
- Date: 2015
- Subjects: International Workshop on Deploying the Future Infrastructure , Computer networks , Computer networks -- Security measures , Computer network protocols
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4722 , http://hdl.handle.net/10962/d1018918
- Description: The IPv6 increased address pool presents changes in resource impact to the Enterprise that, if not adequately addressed, can change risks that are locally significant in IPv4 to risks that can impact the Enterprise in its entirety. The expected conclusion is that the IPv6 environment will impose significant changes in the Enterprise environment - which may negatively impact organisational security if the IPv6 nuances are not adequately addressed. This thesis reviews the risks related to the operation of enterprise networks with the introduction of IPv6. The global trends are discussed to provide insight and background to the IPv6 research space. Analysing the current state of readiness in enterprise networks, quantifies the value of developing this thesis. The base controls that should be deployed in enterprise networks to prevent the abuse of IPv6 through tunnelling and the protection of the enterprise access layer are discussed. A series of case studies are presented which identify and analyse the impact of certain changes in the IPv6 protocol on the enterprise networks. The case studies also identify mitigation techniques to reduce risk.
- Full Text:
- Date Issued: 2015
Exploring Grade 12 biology teachers' perceptions and experiences of the dissemination and utilization of Examiners' reports in the Khomas region of Namibia: a case study
- Authors: Bezuidenhoudt, Anthea
- Date: 2015
- Subjects: Biology -- Examinations -- Namibia , Biology -- Study and teaching -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2021 , http://hdl.handle.net/10962/d1017332
- Description: Teachers’ perceptions are that currently dissemination in schools is ineffective and must change. The tensions that surround the dissemination of the reports are late arrival of Examiners’ reports which clash with preparation of learners for the first term examinations. Furthermore, the time the Examiners’ reports get into teachers’ hands are late and thus result in teachers rushing through it to incorporate the recommendations given in it in the second term or in some instances teachers do not attend to it at all. The number of copies of the Examiners’ reports provided to schools appears to be inadequate. HODs still having to duplicate reports before disseminating them add to their work load and further delay dissemination of the reports to individual subject teachers. Although the teaching and learning approach in Namibian classrooms should be based on LCE, dissemination of the actual physical reports are currently restricted to teachers only with them only verbally communicating feedback given in the reports to their learners. Support in dissemination of Examiners’ reports from peers and superiors in the majority of the schools appear to be lacking. Changes would like to be seen in the timing the Examiners’ reports are available at schools, the number of hard copies provided to schools and exploring and embarking on alternative ways of disseminating the reports. The percentage of utilization of the Examiners’ reports is relatively high, yet still not the optimum. A reasonable number of Namibian learners are disadvantaged and not exposed to a source of information that can make their Biology learning more efficient because some of their teachers are not using Examiners’ reports in their teaching. The main reason for non-utilization of the reports by Biology teachers is a result of inefficient dissemination at individual schools. The argument being that if the reports are not given to the teachers they and especially novice teachers will not know about the existence of this useful teaching and learning resource. Examiners’ reports are an important and systematic impartial source of high quality data on learning in the Namibian education system. Therefore, effective dissemination and utilization of the reports must be advocated and strengthened. DNEA and the Khomas regional office should embark on tapping into available development in information technology by doing research into the possibility of disseminating the Examiners’ reports electronically. A pilot in this regard should be conducted in the Khomas region as a measure to ensure dissemination can become more efficient in the future. To ensure that teachers optimally utilize the Examiners’ reports, they should be provided to schools when the school first term commences. The Khomas regional office should strengthen their involvement in utilization by arranging annual workshops where the content of the reports can be discussed to ensure that the feedback given in the reports can aid in developing and strengthening Biology teachers’ subject content knowledge as well as pedagogical content knowledge. Optimal utilization of Examiners’ reports can enable mediation in learners which can ensure effective learning and mastery of Biology by learners which can ultimately lead to an improvement in pass rate in Biology. Therefore, appropriate support to aid teachers’ professional development can enhance maximum utilization. Furthermore, an area for future research could be to give the Examiners’ reports to learners to determine the impact it has on their learning.
- Full Text:
- Date Issued: 2015
- Authors: Bezuidenhoudt, Anthea
- Date: 2015
- Subjects: Biology -- Examinations -- Namibia , Biology -- Study and teaching -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2021 , http://hdl.handle.net/10962/d1017332
- Description: Teachers’ perceptions are that currently dissemination in schools is ineffective and must change. The tensions that surround the dissemination of the reports are late arrival of Examiners’ reports which clash with preparation of learners for the first term examinations. Furthermore, the time the Examiners’ reports get into teachers’ hands are late and thus result in teachers rushing through it to incorporate the recommendations given in it in the second term or in some instances teachers do not attend to it at all. The number of copies of the Examiners’ reports provided to schools appears to be inadequate. HODs still having to duplicate reports before disseminating them add to their work load and further delay dissemination of the reports to individual subject teachers. Although the teaching and learning approach in Namibian classrooms should be based on LCE, dissemination of the actual physical reports are currently restricted to teachers only with them only verbally communicating feedback given in the reports to their learners. Support in dissemination of Examiners’ reports from peers and superiors in the majority of the schools appear to be lacking. Changes would like to be seen in the timing the Examiners’ reports are available at schools, the number of hard copies provided to schools and exploring and embarking on alternative ways of disseminating the reports. The percentage of utilization of the Examiners’ reports is relatively high, yet still not the optimum. A reasonable number of Namibian learners are disadvantaged and not exposed to a source of information that can make their Biology learning more efficient because some of their teachers are not using Examiners’ reports in their teaching. The main reason for non-utilization of the reports by Biology teachers is a result of inefficient dissemination at individual schools. The argument being that if the reports are not given to the teachers they and especially novice teachers will not know about the existence of this useful teaching and learning resource. Examiners’ reports are an important and systematic impartial source of high quality data on learning in the Namibian education system. Therefore, effective dissemination and utilization of the reports must be advocated and strengthened. DNEA and the Khomas regional office should embark on tapping into available development in information technology by doing research into the possibility of disseminating the Examiners’ reports electronically. A pilot in this regard should be conducted in the Khomas region as a measure to ensure dissemination can become more efficient in the future. To ensure that teachers optimally utilize the Examiners’ reports, they should be provided to schools when the school first term commences. The Khomas regional office should strengthen their involvement in utilization by arranging annual workshops where the content of the reports can be discussed to ensure that the feedback given in the reports can aid in developing and strengthening Biology teachers’ subject content knowledge as well as pedagogical content knowledge. Optimal utilization of Examiners’ reports can enable mediation in learners which can ensure effective learning and mastery of Biology by learners which can ultimately lead to an improvement in pass rate in Biology. Therefore, appropriate support to aid teachers’ professional development can enhance maximum utilization. Furthermore, an area for future research could be to give the Examiners’ reports to learners to determine the impact it has on their learning.
- Full Text:
- Date Issued: 2015
On the characterisation of photovoltaic device parameters using light beam induced current measurements
- Bezuidenhout, Lucian John-Ross
- Authors: Bezuidenhout, Lucian John-Ross
- Date: 2015
- Subjects: Solar cells--Materials , Semiconductors
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10551 , http://hdl.handle.net/10948/d1020282
- Description: Light Beam Induced Current (LBIC) measurement is a non-destructive technique used to perform localized characterization of solar cells using a light beam as a probe. The technique allows the determination of local photo response of a cell, the electrical parameters and defects that occur in the individual solar cell. The semiconductor materials used to create solar cells are not always defect free and these defects reduce the electrical performance of the device. It is therefore important to use a system that will allow the characterization and extract the solar cell parameters as can be done using the LBIC system. By analysing these parameters and cell defects, further studies can be done to enhance the cell’s lifetime and hence its efficiency. Light beam induced current (LBIC) is a technique that focuses light onto a solar cell device and thus creating a photo-generated current that can be measured in the external circuit for analyses. By scanning this beam probe across a solar cell while measuring the current-voltage characteristics, a map of various parameters can be obtained. This thesis presents the design of the LBIC system, the software interfacing of the data acquisition system and local photo-response within different solar cell technologies. In addition, this thesis represent two curve fitting algorithms namely: the Gradient Descent Optimisation and the Differential Evolution used for the extraction of solar cell device parameters. The algorithms are based on the one-diode solar cell model and make use of the light generated current-voltage (I-V) data obtained from the LBIC system. Different solar cell technologies namely; single crystalline (c-Si) and multicrystalline silicon (mc-Si) was used for analysis. LBIC maps and I-V characteristics of both technologies was obtained. The LBIC maps shows performance degrading defects present in the bulk and the surface of the solar cells as a function of spatial distribution. These localised defects acts as trapping mechanism for the charge carriers and therefore limits recombination within the solar cell and thus decreasing the performance of the solar cell device. The resulting I-V characteristics obtained from the LBIC system were used to determine the performance parameters using the two algorithms. The resultant effect of these parameters on the performance of the solar cells was observed. The overall results showed that LBIC is a useful tool for identifying and characterising defects in solar cells.
- Full Text:
- Date Issued: 2015
- Authors: Bezuidenhout, Lucian John-Ross
- Date: 2015
- Subjects: Solar cells--Materials , Semiconductors
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10551 , http://hdl.handle.net/10948/d1020282
- Description: Light Beam Induced Current (LBIC) measurement is a non-destructive technique used to perform localized characterization of solar cells using a light beam as a probe. The technique allows the determination of local photo response of a cell, the electrical parameters and defects that occur in the individual solar cell. The semiconductor materials used to create solar cells are not always defect free and these defects reduce the electrical performance of the device. It is therefore important to use a system that will allow the characterization and extract the solar cell parameters as can be done using the LBIC system. By analysing these parameters and cell defects, further studies can be done to enhance the cell’s lifetime and hence its efficiency. Light beam induced current (LBIC) is a technique that focuses light onto a solar cell device and thus creating a photo-generated current that can be measured in the external circuit for analyses. By scanning this beam probe across a solar cell while measuring the current-voltage characteristics, a map of various parameters can be obtained. This thesis presents the design of the LBIC system, the software interfacing of the data acquisition system and local photo-response within different solar cell technologies. In addition, this thesis represent two curve fitting algorithms namely: the Gradient Descent Optimisation and the Differential Evolution used for the extraction of solar cell device parameters. The algorithms are based on the one-diode solar cell model and make use of the light generated current-voltage (I-V) data obtained from the LBIC system. Different solar cell technologies namely; single crystalline (c-Si) and multicrystalline silicon (mc-Si) was used for analysis. LBIC maps and I-V characteristics of both technologies was obtained. The LBIC maps shows performance degrading defects present in the bulk and the surface of the solar cells as a function of spatial distribution. These localised defects acts as trapping mechanism for the charge carriers and therefore limits recombination within the solar cell and thus decreasing the performance of the solar cell device. The resulting I-V characteristics obtained from the LBIC system were used to determine the performance parameters using the two algorithms. The resultant effect of these parameters on the performance of the solar cells was observed. The overall results showed that LBIC is a useful tool for identifying and characterising defects in solar cells.
- Full Text:
- Date Issued: 2015
Understanding climate variability and livelihoods adaptation in rural Zimbabwe : case of Charewa, Mutoko
- Authors: Bhatasara, Sandra
- Date: 2015
- Subjects: Climatic changes -- Zimbabwe -- Mutoko , Sustainable agriculture -- Zimbabwe -- Mutoko , Environmental impact analysis -- Zimbabwe -- Mutoko , Farmers -- Zimbabwe -- Mutoko -- Economic conditions , Food supply -- Zimbabwe -- Mutoko , Farms -- Zimbabwe -- Mutoko , Land use, Rural -- Zimbabwe -- Mutoko , Crops and climate -- Zimbabwe -- Mutoko
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3403 , http://hdl.handle.net/10962/d1018928 , Climatic changes -- Zimbabwe -- Mutoko , Sustainable agriculture -- Zimbabwe -- Mutoko , Environmental impact analysis -- Zimbabwe -- Mutoko , Farmers -- Zimbabwe -- Mutoko -- Economic conditions , Food supply -- Zimbabwe -- Mutoko , Farms -- Zimbabwe -- Mutoko , Land use, Rural -- Zimbabwe -- Mutoko , Crops and climate -- Zimbabwe -- Mutoko
- Description: Rural farmers in Zimbabwe have been grappling with various changes and challenges occurring in the country since the early 1990s. Amongst these, climate variability has emerged as one significant aspect. It has introduced new challenges for these farmers who are already facing various difficulties in maintaining their insecure livelihoods. Yet, current adaptation theories and inquiries have failed to sufficiently account for and analyse the capacity of these farmers to adequately respond to changing climatic conditions. In this respect, a number of studies have been heavily embedded in deterministic concepts that regard rural farmers as passive victims who play only a minor part in decisions and actions that affect their own livelihoods and well-being. Similarly, although some studies have acknowledged farmers’ capacity to adapt and build elements of resilience, they have not adequately shown how farmers interpret changes in climate and the structures, processes and conditions underpinning adaptation. Following that, my study uses a case study of a rural community in a semi-arid region of Mutoko district in eastern Zimbabwe and Margaret Archer’s sociological theory to understand and analyse how farmers problematise climate variability and respond to it. The study utilises a qualitative approach to divulge the subtleties on how rural people interpret processes of change and adapt to such changes. The thesis found that farmers are encountering increasingly unpredictable and unreliable rainfall patterns as well as shifting temperature conditions which are inducing labyrinthian livelihoods conundrums. However, these climatic shifts are not being experienced in a discrete manner hence farmers are also discontented with the obtaining socio-economic circumstances in the country. Simultaneously, whilst farmers in large part conceived changes in rainfall and temperature to be caused by natural shifts in climate, they also ascribed them to cultural and religious facets. Importantly, the thesis reveals considerable resourcefulness by farmers in the face of nascent changes in climate variability. Farmers have therefore constructed versatile coping and adaptive strategies. What is crucial to mention here is that climatic and non-climatic challenges are negotiated concurrently. Therein, farmers are adapting to climate variability and at the same time navigating difficult socio-economic landscapes. All the same, the process of adaptation is ostensibly not straightforward but complex. As it evolves, farmers find themselves facing numerous constraining structures and processes. Nonetheless, farmers in this study are able to circumvent the constraints presented to them and at the same time activate the corresponding enabling structures, processes and conditions.
- Full Text:
- Date Issued: 2015
- Authors: Bhatasara, Sandra
- Date: 2015
- Subjects: Climatic changes -- Zimbabwe -- Mutoko , Sustainable agriculture -- Zimbabwe -- Mutoko , Environmental impact analysis -- Zimbabwe -- Mutoko , Farmers -- Zimbabwe -- Mutoko -- Economic conditions , Food supply -- Zimbabwe -- Mutoko , Farms -- Zimbabwe -- Mutoko , Land use, Rural -- Zimbabwe -- Mutoko , Crops and climate -- Zimbabwe -- Mutoko
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3403 , http://hdl.handle.net/10962/d1018928 , Climatic changes -- Zimbabwe -- Mutoko , Sustainable agriculture -- Zimbabwe -- Mutoko , Environmental impact analysis -- Zimbabwe -- Mutoko , Farmers -- Zimbabwe -- Mutoko -- Economic conditions , Food supply -- Zimbabwe -- Mutoko , Farms -- Zimbabwe -- Mutoko , Land use, Rural -- Zimbabwe -- Mutoko , Crops and climate -- Zimbabwe -- Mutoko
- Description: Rural farmers in Zimbabwe have been grappling with various changes and challenges occurring in the country since the early 1990s. Amongst these, climate variability has emerged as one significant aspect. It has introduced new challenges for these farmers who are already facing various difficulties in maintaining their insecure livelihoods. Yet, current adaptation theories and inquiries have failed to sufficiently account for and analyse the capacity of these farmers to adequately respond to changing climatic conditions. In this respect, a number of studies have been heavily embedded in deterministic concepts that regard rural farmers as passive victims who play only a minor part in decisions and actions that affect their own livelihoods and well-being. Similarly, although some studies have acknowledged farmers’ capacity to adapt and build elements of resilience, they have not adequately shown how farmers interpret changes in climate and the structures, processes and conditions underpinning adaptation. Following that, my study uses a case study of a rural community in a semi-arid region of Mutoko district in eastern Zimbabwe and Margaret Archer’s sociological theory to understand and analyse how farmers problematise climate variability and respond to it. The study utilises a qualitative approach to divulge the subtleties on how rural people interpret processes of change and adapt to such changes. The thesis found that farmers are encountering increasingly unpredictable and unreliable rainfall patterns as well as shifting temperature conditions which are inducing labyrinthian livelihoods conundrums. However, these climatic shifts are not being experienced in a discrete manner hence farmers are also discontented with the obtaining socio-economic circumstances in the country. Simultaneously, whilst farmers in large part conceived changes in rainfall and temperature to be caused by natural shifts in climate, they also ascribed them to cultural and religious facets. Importantly, the thesis reveals considerable resourcefulness by farmers in the face of nascent changes in climate variability. Farmers have therefore constructed versatile coping and adaptive strategies. What is crucial to mention here is that climatic and non-climatic challenges are negotiated concurrently. Therein, farmers are adapting to climate variability and at the same time navigating difficult socio-economic landscapes. All the same, the process of adaptation is ostensibly not straightforward but complex. As it evolves, farmers find themselves facing numerous constraining structures and processes. Nonetheless, farmers in this study are able to circumvent the constraints presented to them and at the same time activate the corresponding enabling structures, processes and conditions.
- Full Text:
- Date Issued: 2015
WISC-IV test performance of grade 3 Xhosa-speaking children : an extension of a prior South African normative database
- Authors: Bickell, Alexa
- Date: 2015
- Subjects: Wechsler Intelligence Scale for Children Children -- Intelligence testing -- South Africa Education, Elementary -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/5730 , vital:29368
- Description: Introduction. A well-recognized problem exists when commonly employed tests developed in the United States (US) or United Kingdom (UK) are accepted unconditionally for use on local relatively disadvantaged populations, as these tests have questionable validity and therefore incur a high risk of misdiagnosis. Cross-cultural normative research has been conducted in South Africa on some of the Wechsler intelligence scales with respect to participants stratified for level and quality of education, age, race and language, including a study on the Wechsler Intelligence Scale for Children – Fourth Edition (WISC-IV) for learners with Grade 7 education (age 12 to 23). The aim of the current study was to conduct a partial duplication of the earlier WISC-IV South African norming study that specifically targeted a younger group of educationally disadvantaged children at a lower level of education. Method. Participants were Black Xhosa-speaking Grade 3 learners in the age range 8 to 9 (N =32 ), who were being schooled in the disadvantaged educational setting of the former Department of Education and Training (former-DET) schools. The WISC-IV results of the current study were statistically compared with the WISC-IV results from Shuttleworth-Edwards, Van der Merwe et al. (2013) study. Results. There was a significant lowering of between 20 to 30 IQ points relative to the UK standardisation on WISC-IV scores for this sample of Grade 3 Xhosa-speaking learners, replicating the earlier outcome for Grade 7 Xhosa-speaking learners relative to the UK standardisation. No differences were in evidence within the WISC-IV sample for the female and male participants on any of the indices. There was equivalence between the Grade 3 and Grade 7 Xhosa-speaking learners on all subtest and Index scores with the exception of the Digit Span subtest. Conclusions. The results confirm prior research indications of the negative impact of educational disadvantage on IQ test results and the need for this to be taken into account by the availability of socio- culturally relevant norms.
- Full Text:
- Date Issued: 2015
- Authors: Bickell, Alexa
- Date: 2015
- Subjects: Wechsler Intelligence Scale for Children Children -- Intelligence testing -- South Africa Education, Elementary -- South Africa
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/5730 , vital:29368
- Description: Introduction. A well-recognized problem exists when commonly employed tests developed in the United States (US) or United Kingdom (UK) are accepted unconditionally for use on local relatively disadvantaged populations, as these tests have questionable validity and therefore incur a high risk of misdiagnosis. Cross-cultural normative research has been conducted in South Africa on some of the Wechsler intelligence scales with respect to participants stratified for level and quality of education, age, race and language, including a study on the Wechsler Intelligence Scale for Children – Fourth Edition (WISC-IV) for learners with Grade 7 education (age 12 to 23). The aim of the current study was to conduct a partial duplication of the earlier WISC-IV South African norming study that specifically targeted a younger group of educationally disadvantaged children at a lower level of education. Method. Participants were Black Xhosa-speaking Grade 3 learners in the age range 8 to 9 (N =32 ), who were being schooled in the disadvantaged educational setting of the former Department of Education and Training (former-DET) schools. The WISC-IV results of the current study were statistically compared with the WISC-IV results from Shuttleworth-Edwards, Van der Merwe et al. (2013) study. Results. There was a significant lowering of between 20 to 30 IQ points relative to the UK standardisation on WISC-IV scores for this sample of Grade 3 Xhosa-speaking learners, replicating the earlier outcome for Grade 7 Xhosa-speaking learners relative to the UK standardisation. No differences were in evidence within the WISC-IV sample for the female and male participants on any of the indices. There was equivalence between the Grade 3 and Grade 7 Xhosa-speaking learners on all subtest and Index scores with the exception of the Digit Span subtest. Conclusions. The results confirm prior research indications of the negative impact of educational disadvantage on IQ test results and the need for this to be taken into account by the availability of socio- culturally relevant norms.
- Full Text:
- Date Issued: 2015