Investigating the inclusion of environmental learning in the Life Science Grade 10 curriculum : a case study of three Namibian schools
- Authors: Joseph, Cecilia Namuhuya
- Date: 2015
- Subjects: Life sciences -- Study and teaching (Secondary) -- Namibia -- Omusati , Environmental education -- Study and teaching (Secondary) -- Namibia -- Omusati , Curriculum-based assessment -- Namibia -- Omusati , Pedagogical content knowledge , Educational tests and measurements -- Namibia -- Omusati
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2033 , http://hdl.handle.net/10962/d1017344
- Description: This study was carried out to investigate how Grade 10 Life Science teachers in three schools in the Omusati region of Namibia are including Environmental Learning (EL) in terms of the curriculum policy. A qualitative approach was used to generate data through document analysis, interviews and classroom observations to investigate the application of the policy of including environmental learning in classroom curriculum practice. The research was primarily directed towards examining constraints and enabling factors in the context of the three schools that participated in the study. The study revealed that teaching strategies for the inclusion of environmental learning were not widely evident, suggesting disparities between the policy of enabling environmental education through the inclusion of environmental learning across the curriculum. It was notable that teacher knowledge and interest in environmental education influence how they include environmental learning and that assessment practices narrow the scope of environmental learning in ways that do not include critical thinking and problem solving skills. The study concludes that despite diverse constraints inhibiting inclusion, the evidence suggests that the inclusion of environmental learning in Namibia’s Life Science curriculum can enable environmental education. The above main findings are used to make recommendations toward strengthening environmental content knowledge of teachers and to improve assessment practices. It was also noted that some of the environmental learning constraints could be transformed into enablers with more teacher support and by making a better link between environmental learning theories and practices. This will involve a redirection of the curriculum documents as well as the provision of other learning support materials to support environmental learning. The study has enabled me to conclude that what is happening should be encouraged so that it continues and is strengthened although the implementation of environmental learning is not as clear as the policy had mapped out.
- Full Text:
- Authors: Joseph, Cecilia Namuhuya
- Date: 2015
- Subjects: Life sciences -- Study and teaching (Secondary) -- Namibia -- Omusati , Environmental education -- Study and teaching (Secondary) -- Namibia -- Omusati , Curriculum-based assessment -- Namibia -- Omusati , Pedagogical content knowledge , Educational tests and measurements -- Namibia -- Omusati
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:2033 , http://hdl.handle.net/10962/d1017344
- Description: This study was carried out to investigate how Grade 10 Life Science teachers in three schools in the Omusati region of Namibia are including Environmental Learning (EL) in terms of the curriculum policy. A qualitative approach was used to generate data through document analysis, interviews and classroom observations to investigate the application of the policy of including environmental learning in classroom curriculum practice. The research was primarily directed towards examining constraints and enabling factors in the context of the three schools that participated in the study. The study revealed that teaching strategies for the inclusion of environmental learning were not widely evident, suggesting disparities between the policy of enabling environmental education through the inclusion of environmental learning across the curriculum. It was notable that teacher knowledge and interest in environmental education influence how they include environmental learning and that assessment practices narrow the scope of environmental learning in ways that do not include critical thinking and problem solving skills. The study concludes that despite diverse constraints inhibiting inclusion, the evidence suggests that the inclusion of environmental learning in Namibia’s Life Science curriculum can enable environmental education. The above main findings are used to make recommendations toward strengthening environmental content knowledge of teachers and to improve assessment practices. It was also noted that some of the environmental learning constraints could be transformed into enablers with more teacher support and by making a better link between environmental learning theories and practices. This will involve a redirection of the curriculum documents as well as the provision of other learning support materials to support environmental learning. The study has enabled me to conclude that what is happening should be encouraged so that it continues and is strengthened although the implementation of environmental learning is not as clear as the policy had mapped out.
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Investigating the role of media in the identity construction of ethnic minority language speakers in Botswana : an exploratory study of the Bakalanga
- Authors: Thothe, Oesi
- Date: 2015
- Subjects: Linguistic minorities -- Botswana , Kalanga language (Botswana and Zimbabwe) , Kalanga (African people) -- Ethnic identity , Language policy -- Botswana , Mass media and language -- Botswana , Mass media and ethnic relations -- Botswana , Mass media -- Audiences , Mass media -- Social aspects -- Botswana
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3547 , http://hdl.handle.net/10962/d1017788
- Description: This dissertation investigates the role of media in the identity construction of minority language speakers in Botswana, with a focus on the Bakalanga. The study is informed by debates around the degree to which the media can be seen to play a central role in the way the Bakalanga define their own identity. As part of this, it considers how such individuals understand their own sense of identity to be located within processes of nation-building, and in particular in relation to the construction of a national identity. It focuses, more particularly, on the extent to which the absence of particular languages within media can be said to impact on such processes of identity formation. The study responds, at the same time, to the argument that people’s more general lived experiences and their broader social environment have a bearing on how they make sense of the media. As such, it can be seen to critique the assumption that the media necessarily play a central and defining role within processes of socialisation. In order to explore the significance of these debates for a study of the Bakalanga, the dissertation includes a contextual discussion of language policy in Botswana, the impact of colonial history on such policy and the implications that this has had for the linguistic identity of the media. It also reviews theoretical debates that help to make sense of the role that the media plays within the processes through which minority language speakers construct their own identity. Finally, it includes an empirical case study, consisting of qualitative interviews with individuals who identify themselves as Bakalanga. It is argued that, because of the absence of their own language from the media, the respondents do not describe the media as central to their own processes of identity formation. At the same time, the respondents recognise the importance of the media within society, and are preoccupied with their own marginalisation from the media. The study explores the way the respondents make sense of such marginalisation, as demonstrated by their attempts to seek alternative media platforms in which they can find recognition of their own language and social experience. The study thus reaffirms the significance of media in society – even for people who feel that they are not recognised within such media.
- Full Text:
- Authors: Thothe, Oesi
- Date: 2015
- Subjects: Linguistic minorities -- Botswana , Kalanga language (Botswana and Zimbabwe) , Kalanga (African people) -- Ethnic identity , Language policy -- Botswana , Mass media and language -- Botswana , Mass media and ethnic relations -- Botswana , Mass media -- Audiences , Mass media -- Social aspects -- Botswana
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3547 , http://hdl.handle.net/10962/d1017788
- Description: This dissertation investigates the role of media in the identity construction of minority language speakers in Botswana, with a focus on the Bakalanga. The study is informed by debates around the degree to which the media can be seen to play a central role in the way the Bakalanga define their own identity. As part of this, it considers how such individuals understand their own sense of identity to be located within processes of nation-building, and in particular in relation to the construction of a national identity. It focuses, more particularly, on the extent to which the absence of particular languages within media can be said to impact on such processes of identity formation. The study responds, at the same time, to the argument that people’s more general lived experiences and their broader social environment have a bearing on how they make sense of the media. As such, it can be seen to critique the assumption that the media necessarily play a central and defining role within processes of socialisation. In order to explore the significance of these debates for a study of the Bakalanga, the dissertation includes a contextual discussion of language policy in Botswana, the impact of colonial history on such policy and the implications that this has had for the linguistic identity of the media. It also reviews theoretical debates that help to make sense of the role that the media plays within the processes through which minority language speakers construct their own identity. Finally, it includes an empirical case study, consisting of qualitative interviews with individuals who identify themselves as Bakalanga. It is argued that, because of the absence of their own language from the media, the respondents do not describe the media as central to their own processes of identity formation. At the same time, the respondents recognise the importance of the media within society, and are preoccupied with their own marginalisation from the media. The study explores the way the respondents make sense of such marginalisation, as demonstrated by their attempts to seek alternative media platforms in which they can find recognition of their own language and social experience. The study thus reaffirms the significance of media in society – even for people who feel that they are not recognised within such media.
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Investigations into insect-induced plant responses of water hyacinth (Eichhornia crassipes (Mart.) Solms-Laub.) (Pontederiaceae)
- Authors: May, Bronwen
- Date: 2015
- Subjects: Water hyacinth , Water hyacinth -- Biological control , Water hyacinth -- Defenses , Aquatic weeds , Insect-plant relationships , Miridae , Curculionidae
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5940 , http://hdl.handle.net/10962/d1018906
- Description: The water hyacinth (Eichhornia crassipes (Mart.) Solms-Laub (Pontederiaceae)) biological control programme makes use of tight plant-insect interactions to control the weed, by reestablishing the interactions between the plant and its natural enemies. Since the beginning of the water hyacinth biological control initiative, the impact of biological control agent herbivory on water hyacinth’s population growth and fitness have been well documented; however, very few investigations have been conducted to determine whether herbivory elicits insect-induced responses by water hyacinth. Studies were conducted to determine the presence and function of water hyacinth insectinduced responses, using the plant activator, BION®, in attempt to determine the plant hormone-mediated pathways regulating the final expressions of insect-induced defences in response to herbivory by the phloem-feeder, Eccritotarsus catarinensis (Carvalho) (Hemiptera: Miridae) and the leaf chewer, Neochetina bruchi Hustache (Coleoptera: Curculionidae). BION® (Syngenta, acibensolar-S-methyl (benzothiadiazole)) is a dissolvable, granular formulation that contains a chemical analogue of the plant hormone, salicylic acid (SA), which typically regulates defences against pathogens. The application of BION® results in the induction of the SA-mediated defence pathways in plants (activation of defences against pathogens), and consequently the inhibition of the jasmonic acid (JA)- mediated defence pathways (de-activation of defences against insect herbivores). To test for induced defence responses in water hyacinth, plants treated with BION® and then subjected to herbivory, were compared to un-treated plants that were also subjected to herbivory, BION®-only treated plants and control plants. The application of BION® did not confer resistance against the two insect herbivores, as herbivory, reductions in chlorophyll content and plant growth (leaf production and second petiole lengths) significantly increased in comparison to non-BION® treated plants. Furthermore, palatability indices significantly increased (>1.00) in BION® treated plants, reflecting increased weevil preferences for SAinduced water hyacinth plants. This concluded that SA-mediated defences are not effective against insect herbivory in water hyacinth plants, but are in fact palatable to insect herbivores, which reflects ecological and physiological costs of SA-mediated defences (pathogen defences) in water hyacinth. Biochemical analyses of leaves exhibited increases in nitrogen content in BION® treated plants. These elevated levels of nitrogenous compounds account for the increases in mirid and weevil preferences for BION® treated plants. The increases in nitrogenous compounds are probably structural proteins (e.g. peroxidises), because leaves treated with BION® increased in toughness, but only when exposed to herbivory. Regardless, insect herbivory was elevated on these leaves, probably because the nitrogenous compounds were nutritionally viable for the insects.
- Full Text:
- Authors: May, Bronwen
- Date: 2015
- Subjects: Water hyacinth , Water hyacinth -- Biological control , Water hyacinth -- Defenses , Aquatic weeds , Insect-plant relationships , Miridae , Curculionidae
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5940 , http://hdl.handle.net/10962/d1018906
- Description: The water hyacinth (Eichhornia crassipes (Mart.) Solms-Laub (Pontederiaceae)) biological control programme makes use of tight plant-insect interactions to control the weed, by reestablishing the interactions between the plant and its natural enemies. Since the beginning of the water hyacinth biological control initiative, the impact of biological control agent herbivory on water hyacinth’s population growth and fitness have been well documented; however, very few investigations have been conducted to determine whether herbivory elicits insect-induced responses by water hyacinth. Studies were conducted to determine the presence and function of water hyacinth insectinduced responses, using the plant activator, BION®, in attempt to determine the plant hormone-mediated pathways regulating the final expressions of insect-induced defences in response to herbivory by the phloem-feeder, Eccritotarsus catarinensis (Carvalho) (Hemiptera: Miridae) and the leaf chewer, Neochetina bruchi Hustache (Coleoptera: Curculionidae). BION® (Syngenta, acibensolar-S-methyl (benzothiadiazole)) is a dissolvable, granular formulation that contains a chemical analogue of the plant hormone, salicylic acid (SA), which typically regulates defences against pathogens. The application of BION® results in the induction of the SA-mediated defence pathways in plants (activation of defences against pathogens), and consequently the inhibition of the jasmonic acid (JA)- mediated defence pathways (de-activation of defences against insect herbivores). To test for induced defence responses in water hyacinth, plants treated with BION® and then subjected to herbivory, were compared to un-treated plants that were also subjected to herbivory, BION®-only treated plants and control plants. The application of BION® did not confer resistance against the two insect herbivores, as herbivory, reductions in chlorophyll content and plant growth (leaf production and second petiole lengths) significantly increased in comparison to non-BION® treated plants. Furthermore, palatability indices significantly increased (>1.00) in BION® treated plants, reflecting increased weevil preferences for SAinduced water hyacinth plants. This concluded that SA-mediated defences are not effective against insect herbivory in water hyacinth plants, but are in fact palatable to insect herbivores, which reflects ecological and physiological costs of SA-mediated defences (pathogen defences) in water hyacinth. Biochemical analyses of leaves exhibited increases in nitrogen content in BION® treated plants. These elevated levels of nitrogenous compounds account for the increases in mirid and weevil preferences for BION® treated plants. The increases in nitrogenous compounds are probably structural proteins (e.g. peroxidises), because leaves treated with BION® increased in toughness, but only when exposed to herbivory. Regardless, insect herbivory was elevated on these leaves, probably because the nitrogenous compounds were nutritionally viable for the insects.
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IsiXhosa storytelling (iintsomi) as an alternative medium for maternal health education in primary healthcare in the Eastern Cape
- Authors: Zakaza, Nompucuko
- Date: 2015
- Subjects: Communication in community health services -- South Africa -- Eastern Cape , Communication in reproductive health -- South Africa -- Eastern Cape , Storytelling in education , Applied folklore
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3648 , http://hdl.handle.net/10962/d1017188
- Description: The aim of this study is to explore the introduction of IsiXhosa (iintsomi) as an alternative method in the maternal health education in rural Primary Health Care in the Eastern Cape. An informal preliminary observation of a maternal health lesson by the researcher indicated a further need for maternal health educators to introduce storytelling into the health content themes. To re-inforce the maternal health educator lesson on the causes of teenage pregnancy, lifestyles for pregnant women, causes of miscarriage and termination of pregnancy, the Community Health Workers can undoubtedly use isiXhosa iintsomi in selected clinics and maternal waiting homes. As a readily available resource that cuts across all literacy barriers, iintsomi (isiXhosa) fosters a cross-cultural consultation which enables the healthcare worker to convey messages that make sense to the rural women. While the conventional methods of teaching have a tendency to create tension and lack of participation, use of folktale (iintsomi) have huge potential to bring lesson enjoyment; a meaningful interaction and story sharing by the maternal health educator, the pregnant women and greater community; access to important health messages; and strengthened utilisation of Primary Health Care. The study therefore suggests that there is a place for isiXhosa iintsomi: From the Fireplace into the Workplace.
- Full Text:
- Authors: Zakaza, Nompucuko
- Date: 2015
- Subjects: Communication in community health services -- South Africa -- Eastern Cape , Communication in reproductive health -- South Africa -- Eastern Cape , Storytelling in education , Applied folklore
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3648 , http://hdl.handle.net/10962/d1017188
- Description: The aim of this study is to explore the introduction of IsiXhosa (iintsomi) as an alternative method in the maternal health education in rural Primary Health Care in the Eastern Cape. An informal preliminary observation of a maternal health lesson by the researcher indicated a further need for maternal health educators to introduce storytelling into the health content themes. To re-inforce the maternal health educator lesson on the causes of teenage pregnancy, lifestyles for pregnant women, causes of miscarriage and termination of pregnancy, the Community Health Workers can undoubtedly use isiXhosa iintsomi in selected clinics and maternal waiting homes. As a readily available resource that cuts across all literacy barriers, iintsomi (isiXhosa) fosters a cross-cultural consultation which enables the healthcare worker to convey messages that make sense to the rural women. While the conventional methods of teaching have a tendency to create tension and lack of participation, use of folktale (iintsomi) have huge potential to bring lesson enjoyment; a meaningful interaction and story sharing by the maternal health educator, the pregnant women and greater community; access to important health messages; and strengthened utilisation of Primary Health Care. The study therefore suggests that there is a place for isiXhosa iintsomi: From the Fireplace into the Workplace.
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Isolation and structure elucidation of halogenated metabolites from Portieria hornemannii and Portieria tripinnata
- Authors: Adam, Mohammed
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64674 , vital:28591
- Description: The red marine algal genus, Portieria, is known to produce a number of potent cytotoxic compounds with anticancer potential. The most important anticancer lead produced by this genus is the compound halomon. Unfortunately, the lack of sufficient quantities of this compound hampered its further development. Two Portieria species, Portieria hornemannii and Portieria tripinnata, are found along the South African coastline. Recent studies, based on DNA analysis, suggest that Portieria hornemannii may in fact be divided into several cryptic species. The current project is part of a larger study designed to investigate the use of secondary metabolites to identify new marine algal species. In this study 1H NMR profiles of the organic extracts of selected Portieria spp were compared in order to identify new species. Selected compounds were then isolated and characterised as potential chemotaxonomic markers. Four halogenated monoterpenes were isolated from Portieria hornemannii. Two of these were new compounds 4-(3-bromo-4-chloro-4-methylpentyl)-3-chlorofuran-2(5H)-one, which were isomers of each other. The two known compounds had been previously isolated from Portieria hornemannii samples off the Madagascar coast. These compounds could prove to be useful as chemotaxonomic marker compounds, as they have never been isolated from any other species of marine algae. Three known halogenated monoterpenes were isolated from Portieria tripinnata. These compounds had been previously isolated from different species of marine algae and therefore, could not serve as chemotaxonomic marker compounds for this species of marine alga. Further work needs to be done on Portieria tripinnata, with regards to its chemistry, as it is a species of marine algae that has not been previously researched.
- Full Text:
- Authors: Adam, Mohammed
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/64674 , vital:28591
- Description: The red marine algal genus, Portieria, is known to produce a number of potent cytotoxic compounds with anticancer potential. The most important anticancer lead produced by this genus is the compound halomon. Unfortunately, the lack of sufficient quantities of this compound hampered its further development. Two Portieria species, Portieria hornemannii and Portieria tripinnata, are found along the South African coastline. Recent studies, based on DNA analysis, suggest that Portieria hornemannii may in fact be divided into several cryptic species. The current project is part of a larger study designed to investigate the use of secondary metabolites to identify new marine algal species. In this study 1H NMR profiles of the organic extracts of selected Portieria spp were compared in order to identify new species. Selected compounds were then isolated and characterised as potential chemotaxonomic markers. Four halogenated monoterpenes were isolated from Portieria hornemannii. Two of these were new compounds 4-(3-bromo-4-chloro-4-methylpentyl)-3-chlorofuran-2(5H)-one, which were isomers of each other. The two known compounds had been previously isolated from Portieria hornemannii samples off the Madagascar coast. These compounds could prove to be useful as chemotaxonomic marker compounds, as they have never been isolated from any other species of marine algae. Three known halogenated monoterpenes were isolated from Portieria tripinnata. These compounds had been previously isolated from different species of marine algae and therefore, could not serve as chemotaxonomic marker compounds for this species of marine alga. Further work needs to be done on Portieria tripinnata, with regards to its chemistry, as it is a species of marine algae that has not been previously researched.
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Language policy and practice in Eastern Cape courtrooms with reference to interpretation in selected cases
- Authors: Mpahlwa, Matthew Xola
- Date: 2015
- Subjects: Translating and interpreting , Translating and interpreting -- Errors , Court interpreting and translating -- South Africa -- Eastern Cape , Translators -- Training of -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3656 , http://hdl.handle.net/10962/d1018658
- Description: This study seeks to find what problems and process of interpreting are experienced by professional interpreters in the criminal justice system in South Africa. This study commences with an outlook of the origins and development of types of interpretation and then proceeds with critical review of scholarly literature dealing with interpretation in multilingual courtroom. This study explores the flawed language policy and its impracticality for the Eastern Cape courtrooms. This study undertakes a critical analysis of the current legislation (Bills & Acts).This study explores the extent to which the court automatic review proceedings act as a gatekeeper in ensuring against prejudice that can result in the non-use and use of indigenous languages in the trial courtroom within the Eastern Cape jurisdiction. Furthermore this study focuses on cases taken for review based on mis-understanding, mis-communication and wrongful interpretation that result in irregularities that appear on court records. This study also investigates the primary barriers for the use of African languages as languages of record in the courtroom. An eclectic sociolinguistic approach which encompasses the ethnography of speaking, and discourse analysis (observation in the courtroom) is used as a methodology in this study. Furthermore, the analysis of case-law forms part of the methodology alongside court observation.This study saw court actors from different spheres of the legal profession give their personal views and encounters with regards the art and the state of court interpreting in the province of the Eastern Cape.This state of affairs may have disastrous and far-reaching effects in that incorrect and/or imperfect translation may relate to the very facts that are crucial for the determination of the case. At the end recommendations are given on how to remedy the current state of affairs.
- Full Text:
- Authors: Mpahlwa, Matthew Xola
- Date: 2015
- Subjects: Translating and interpreting , Translating and interpreting -- Errors , Court interpreting and translating -- South Africa -- Eastern Cape , Translators -- Training of -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3656 , http://hdl.handle.net/10962/d1018658
- Description: This study seeks to find what problems and process of interpreting are experienced by professional interpreters in the criminal justice system in South Africa. This study commences with an outlook of the origins and development of types of interpretation and then proceeds with critical review of scholarly literature dealing with interpretation in multilingual courtroom. This study explores the flawed language policy and its impracticality for the Eastern Cape courtrooms. This study undertakes a critical analysis of the current legislation (Bills & Acts).This study explores the extent to which the court automatic review proceedings act as a gatekeeper in ensuring against prejudice that can result in the non-use and use of indigenous languages in the trial courtroom within the Eastern Cape jurisdiction. Furthermore this study focuses on cases taken for review based on mis-understanding, mis-communication and wrongful interpretation that result in irregularities that appear on court records. This study also investigates the primary barriers for the use of African languages as languages of record in the courtroom. An eclectic sociolinguistic approach which encompasses the ethnography of speaking, and discourse analysis (observation in the courtroom) is used as a methodology in this study. Furthermore, the analysis of case-law forms part of the methodology alongside court observation.This study saw court actors from different spheres of the legal profession give their personal views and encounters with regards the art and the state of court interpreting in the province of the Eastern Cape.This state of affairs may have disastrous and far-reaching effects in that incorrect and/or imperfect translation may relate to the very facts that are crucial for the determination of the case. At the end recommendations are given on how to remedy the current state of affairs.
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Learners' numeracy progression and the role of mediation in the context of two after school mathematics clubs
- Authors: Stott, Deborah Ann
- Date: 2015
- Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa , After-school programs -- South Africa , Numeracy -- Study and teaching (Elementary) -- South Africa , Learning, Psychology of , Education -- Research -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2017 , http://hdl.handle.net/10962/d1017181
- Description: National and international assessment results, research studies and reports point to South Africa as having educational challenges, specifically with mathematics, science and language. Addressing some of these issues is a key aim for the SANC project at Rhodes University, the context in which this study takes place. Working from a broad Vygotskian perspective of learning and development, this study had a dual focus and investigated how Grade 3 learners’ mathematical proficiency progressed (or not) whilst participating in after school maths clubs over the course of a year, and explored how the mediation offered in the clubs enabled or constrained the emergence of zones of proximal development (ZPD) and thus learning for the club learners. Methodologically, this study works within a largely qualitative, interpretive research paradigm and is designed using a longitudinal case study research strategy. Two after school maths clubs formed the empirical field. The study drew on a range of data collection methods to investigate the dual nature of the research questions for Grade 3 learners. Examples include adapted one-to-one mathematical proficiency interviews and paired task based interviews. The study highlighted the relationship between the multiple roles I played both within the research study and within the SANC project context and emphasises the influence and future implications for these various roles within the SANC project and beyond in terms of my own role as club mentor, for the future design of the SANC project maths club programme and for broader teacher and club facilitator development within and beyond the project. This study has offered insight into how mathematical proficiency may develop in Grade 3 South African learners and as such is an important contribution to the newly developing field of both numeracy and primary educational research in Southern Africa. Additionally, the research findings point to the clubs, as an example of an out-of-school time (OST) programme, providing potentially enabling spaces for both recovery and extension of mathematical proficiency in learners as these spaces are free from several contextual constraints that teachers face in their classrooms. Furthermore, it was found that learners showed development of their conceptual understanding, procedural fluency and adaptive reasoning as proposed by Kilpatrick, Swafford and Findell (2001). The use of various elements of the Maths Recovery (MR) programme (Wright, 2003) in the research process has highlighted various important contributions for broader research. For example, the need to investigate less time consuming approaches to both diagnostic assessment and learner mathematical profiling. Findings from this study support Meira and Lerman’s (2001, 2009) recently developed notion that catching attention is key to the creation or emergence of a ZPD. The study found that a combination of ‘attention catching’ and ‘tuning in’ enabled the creation (emergence) and sustainment of ZPDs in club learners. The study proposed the notion of tuning in where participants in a mathematical interaction continually adjust to each other in order to communicate mathematically. Furthermore, the study found that when attention is not caught or the participants are not tuned in, the learning activity may still be useful in assisting learners to consolidate their existing learning and / or build confidence and as such is particularly relevant to the South African context where fluency in calculating is weak (Hoadley, 2012; Schollar, 2008). This emergent notion of ‘flow’ additionally can play a supporting role in the emergence of a ZPD. The study also found that the manner in which the mediation was offered is important. The results show that the mathematical contributions learners make during interactions captured the mentors’ attention and resulted in mediation that was intentional but spontaneous, flexible, responsive and in-the-moment. This study makes theoretical and methodological contributions to various aspects of mathematics education research particularly with regard to how ZPDs emerge and are sustained and how mediation is offered to facilitate the emergence of ZPDs. Additionally, some aspects of the Learning Framework in Number (LFIN) as part of the Maths Recovery programme have been extended to work in a South African after school club context and to provide useful information for both learner progression over time and for planning of club activities. As such this study thus also contributes to the newly developing field of primary mathematics research in South Africa and to the body of research on primary after school learning programmes both locally and internationally.
- Full Text:
- Authors: Stott, Deborah Ann
- Date: 2015
- Subjects: Mathematics -- Study and teaching (Elementary) -- South Africa , After-school programs -- South Africa , Numeracy -- Study and teaching (Elementary) -- South Africa , Learning, Psychology of , Education -- Research -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2017 , http://hdl.handle.net/10962/d1017181
- Description: National and international assessment results, research studies and reports point to South Africa as having educational challenges, specifically with mathematics, science and language. Addressing some of these issues is a key aim for the SANC project at Rhodes University, the context in which this study takes place. Working from a broad Vygotskian perspective of learning and development, this study had a dual focus and investigated how Grade 3 learners’ mathematical proficiency progressed (or not) whilst participating in after school maths clubs over the course of a year, and explored how the mediation offered in the clubs enabled or constrained the emergence of zones of proximal development (ZPD) and thus learning for the club learners. Methodologically, this study works within a largely qualitative, interpretive research paradigm and is designed using a longitudinal case study research strategy. Two after school maths clubs formed the empirical field. The study drew on a range of data collection methods to investigate the dual nature of the research questions for Grade 3 learners. Examples include adapted one-to-one mathematical proficiency interviews and paired task based interviews. The study highlighted the relationship between the multiple roles I played both within the research study and within the SANC project context and emphasises the influence and future implications for these various roles within the SANC project and beyond in terms of my own role as club mentor, for the future design of the SANC project maths club programme and for broader teacher and club facilitator development within and beyond the project. This study has offered insight into how mathematical proficiency may develop in Grade 3 South African learners and as such is an important contribution to the newly developing field of both numeracy and primary educational research in Southern Africa. Additionally, the research findings point to the clubs, as an example of an out-of-school time (OST) programme, providing potentially enabling spaces for both recovery and extension of mathematical proficiency in learners as these spaces are free from several contextual constraints that teachers face in their classrooms. Furthermore, it was found that learners showed development of their conceptual understanding, procedural fluency and adaptive reasoning as proposed by Kilpatrick, Swafford and Findell (2001). The use of various elements of the Maths Recovery (MR) programme (Wright, 2003) in the research process has highlighted various important contributions for broader research. For example, the need to investigate less time consuming approaches to both diagnostic assessment and learner mathematical profiling. Findings from this study support Meira and Lerman’s (2001, 2009) recently developed notion that catching attention is key to the creation or emergence of a ZPD. The study found that a combination of ‘attention catching’ and ‘tuning in’ enabled the creation (emergence) and sustainment of ZPDs in club learners. The study proposed the notion of tuning in where participants in a mathematical interaction continually adjust to each other in order to communicate mathematically. Furthermore, the study found that when attention is not caught or the participants are not tuned in, the learning activity may still be useful in assisting learners to consolidate their existing learning and / or build confidence and as such is particularly relevant to the South African context where fluency in calculating is weak (Hoadley, 2012; Schollar, 2008). This emergent notion of ‘flow’ additionally can play a supporting role in the emergence of a ZPD. The study also found that the manner in which the mediation was offered is important. The results show that the mathematical contributions learners make during interactions captured the mentors’ attention and resulted in mediation that was intentional but spontaneous, flexible, responsive and in-the-moment. This study makes theoretical and methodological contributions to various aspects of mathematics education research particularly with regard to how ZPDs emerge and are sustained and how mediation is offered to facilitate the emergence of ZPDs. Additionally, some aspects of the Learning Framework in Number (LFIN) as part of the Maths Recovery programme have been extended to work in a South African after school club context and to provide useful information for both learner progression over time and for planning of club activities. As such this study thus also contributes to the newly developing field of primary mathematics research in South Africa and to the body of research on primary after school learning programmes both locally and internationally.
- Full Text:
Link between ghost artefacts, source suppression and incomplete calibration sky models
- Authors: Nunhokee, Chuneeta Devi
- Date: 2015
- Subjects: Interferometry , Calibration
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5556 , http://hdl.handle.net/10962/d1017900
- Description: Calibration is a fundamental step towards producing radio interferometric images. However, naive calibration produces calibration artefacts, in the guise of spurious emission, buried in the thermal noise. This work investigates these calibration artefacts, henceforth referred to as “ghosts”. A 21 cm observation with the Westerbork Synthesis Radio Telescope yielded similar ghost sources, and it was anticipated that they were due to calibrating with incomplete sky models. An analytical ghost distribution of a two-source scenario is derived to substantiate this theory and to seek answers to the related bewildering features (regular ghost pattern, points spread function-like sidelobes, independent of model flux). The theoretically predicted ghost distribution qualitatively matches with the observational ones and shows high dependence on the array geometry. The theory draws the conclusion that both the ghost phenomenon and suppression of the unmodelled flux have the same root cause. In addition, the suppression of the unmodelled flux is studied as functions of unmodelled flux, differential gain solution interval and the number of sources subjected to direction-dependent gains. These studies summarise that the suppression rate is constant irrespective of the degree of incompleteness of the calibration sky model. In the presence of a direction-dependent effect, the suppression drastically increases; however, this increase can be compensated for by using longer solution intervals.
- Full Text:
- Authors: Nunhokee, Chuneeta Devi
- Date: 2015
- Subjects: Interferometry , Calibration
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5556 , http://hdl.handle.net/10962/d1017900
- Description: Calibration is a fundamental step towards producing radio interferometric images. However, naive calibration produces calibration artefacts, in the guise of spurious emission, buried in the thermal noise. This work investigates these calibration artefacts, henceforth referred to as “ghosts”. A 21 cm observation with the Westerbork Synthesis Radio Telescope yielded similar ghost sources, and it was anticipated that they were due to calibrating with incomplete sky models. An analytical ghost distribution of a two-source scenario is derived to substantiate this theory and to seek answers to the related bewildering features (regular ghost pattern, points spread function-like sidelobes, independent of model flux). The theoretically predicted ghost distribution qualitatively matches with the observational ones and shows high dependence on the array geometry. The theory draws the conclusion that both the ghost phenomenon and suppression of the unmodelled flux have the same root cause. In addition, the suppression of the unmodelled flux is studied as functions of unmodelled flux, differential gain solution interval and the number of sources subjected to direction-dependent gains. These studies summarise that the suppression rate is constant irrespective of the degree of incompleteness of the calibration sky model. In the presence of a direction-dependent effect, the suppression drastically increases; however, this increase can be compensated for by using longer solution intervals.
- Full Text:
Livelihoods and climate change in Hamburg: issues for food security
- Authors: Martens, Brendon
- Date: 2015
- Subjects: Climatic changes -- South Africa -- Eastern Cape. , Climatic changes -- Risk management -- South Africa -- Eastern Cape , Climatic changes -- Effect of human beings on , Climatic changes -- Agriculture
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1116 , http://hdl.handle.net/10962/d1017538
- Description: Climate change continues to present a major challenge to food security around the world. The potential impact of climate change of rural livelihoods is especially significant as rural communities often rely heavily on natural resources to sustain their livelihoods and, hence, food security. This is applicable to the rural town of Hamburg, on the Eastern Cape coast of South Africa. The Sustainable Rural Livelihoods framework analyses livelihoods in terms of the context, available capitals and institutional framework that determines the livelihood strategies and outcomes for rural households. In terms of livelihood outcomes for Hamburg, it was found that the households have a heavy reliance on state grants in their livelihood portfolios. Natural resources, in the form of agriculture and harvesting of marine organisms, played only a supplementary role in livelihood strategies. Thus, given that climate change would impact negatively on the estuarine resources and the impact on agriculture is unknown as the climate becomes wetter and hotter, the impact on livelihoods and food security would not be significant. However, the sustainability of current livelihood strategies is questionable as grants, by their very nature, or unsustainable and therefore can result in vulnerability and food insecurity in the long-run for households. It is recommended that grants should be issued within the community, instead of in the distant town of Peddie, to help develop the local economy and reduce leakages. This would allow for diversification of livelihood strategies in Hamburg. In addition, government support through extension officers should be extended to Hamburg to assist in developing the local agriculture sector
- Full Text:
- Authors: Martens, Brendon
- Date: 2015
- Subjects: Climatic changes -- South Africa -- Eastern Cape. , Climatic changes -- Risk management -- South Africa -- Eastern Cape , Climatic changes -- Effect of human beings on , Climatic changes -- Agriculture
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1116 , http://hdl.handle.net/10962/d1017538
- Description: Climate change continues to present a major challenge to food security around the world. The potential impact of climate change of rural livelihoods is especially significant as rural communities often rely heavily on natural resources to sustain their livelihoods and, hence, food security. This is applicable to the rural town of Hamburg, on the Eastern Cape coast of South Africa. The Sustainable Rural Livelihoods framework analyses livelihoods in terms of the context, available capitals and institutional framework that determines the livelihood strategies and outcomes for rural households. In terms of livelihood outcomes for Hamburg, it was found that the households have a heavy reliance on state grants in their livelihood portfolios. Natural resources, in the form of agriculture and harvesting of marine organisms, played only a supplementary role in livelihood strategies. Thus, given that climate change would impact negatively on the estuarine resources and the impact on agriculture is unknown as the climate becomes wetter and hotter, the impact on livelihoods and food security would not be significant. However, the sustainability of current livelihood strategies is questionable as grants, by their very nature, or unsustainable and therefore can result in vulnerability and food insecurity in the long-run for households. It is recommended that grants should be issued within the community, instead of in the distant town of Peddie, to help develop the local economy and reduce leakages. This would allow for diversification of livelihood strategies in Hamburg. In addition, government support through extension officers should be extended to Hamburg to assist in developing the local agriculture sector
- Full Text:
Love in a cold war
- Authors: Christenson, Anna
- Date: 2015
- Subjects: South African fiction (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:5988
- Description: A collection of short stories in two parts written in realist and fabulist styles. The first part looks at the post-war generation of baby boomers growing up in the American Midwest. The second half follows an American abroad and explores themes of disintegration, the shifting power balance in relationships and the terrible hole at the core of expatriate identity.
- Full Text:
- Authors: Christenson, Anna
- Date: 2015
- Subjects: South African fiction (English) -- 21st century
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:5988
- Description: A collection of short stories in two parts written in realist and fabulist styles. The first part looks at the post-war generation of baby boomers growing up in the American Midwest. The second half follows an American abroad and explores themes of disintegration, the shifting power balance in relationships and the terrible hole at the core of expatriate identity.
- Full Text:
Mapping and prediction of archaeological sites of habitation by modern humans using GIS and expert mapping on the south coast of South Africa
- Authors: Kleyn, Philippa May
- Date: 2015
- Subjects: Geographic information systems -- South Africa , Archaeological sites , Kitchen-middens -- South Africa , Prehistoric peoples -- South Africa , Prehistoric peoples -- Dwellings -- South Africa , Geological mapping -- South Africa , Coastal archaeology -- South Africa , Archaeological significance -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4890 , http://hdl.handle.net/10962/d1018662
- Description: South Africa contains many archaeological resources including shell middens from the Middle Stone Age (MSA) and Later Stone Age (LSA). These shell middens give researchers insight into the behaviour of modern humans where the first fossil evidence appears in Africa around 200 000 years ago (Klein, 2008). Research into shell middens is therefore vital to understand the origin of human kind. This study investigates whether Geographical Information Systems (GIS) is a useful tool for predicting locations of unknown shell midden sites using the characteristics of known areas of modern human habitation. This was done using suitability analysis and expert mapping techniques. Ground truthing of the results of the desktop analysis revealed that GIS is not a useful tool for predicting sites of modern habitation as the characteristics that determine human habitation are too variable.
- Full Text:
- Authors: Kleyn, Philippa May
- Date: 2015
- Subjects: Geographic information systems -- South Africa , Archaeological sites , Kitchen-middens -- South Africa , Prehistoric peoples -- South Africa , Prehistoric peoples -- Dwellings -- South Africa , Geological mapping -- South Africa , Coastal archaeology -- South Africa , Archaeological significance -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4890 , http://hdl.handle.net/10962/d1018662
- Description: South Africa contains many archaeological resources including shell middens from the Middle Stone Age (MSA) and Later Stone Age (LSA). These shell middens give researchers insight into the behaviour of modern humans where the first fossil evidence appears in Africa around 200 000 years ago (Klein, 2008). Research into shell middens is therefore vital to understand the origin of human kind. This study investigates whether Geographical Information Systems (GIS) is a useful tool for predicting locations of unknown shell midden sites using the characteristics of known areas of modern human habitation. This was done using suitability analysis and expert mapping techniques. Ground truthing of the results of the desktop analysis revealed that GIS is not a useful tool for predicting sites of modern habitation as the characteristics that determine human habitation are too variable.
- Full Text:
Metallophthalocyanine-gold nanoparticle conjugates for photodynamic antimicrobial chemotherapy
- Mthethwa, Thandekile Phakamisiwe
- Authors: Mthethwa, Thandekile Phakamisiwe
- Date: 2015
- Subjects: Nanochemistry , Phthalocyanines , Photochemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4543 , http://hdl.handle.net/10962/d1017923
- Description: This thesis presents the synthesis of neutral and cationic metallophthalocyanines and their gold nanoparticles conjugates. The spectroscopic characterization of these compounds is presented herein. The studies presented in this work shows that the conjugation of gold nanoparticles influenced both photophysical and photochemical properties. Gold nanoparticles were found to enhance the singlet oxygen quantum yield while lowering the fluorescence quantum yields. This work also looks at the effect of anisotropic gold nanoparticles such as nanorods and bipyramids on the photophysical behaviour of the metallophthalocyanines. The effect of the size of the gold nanorods was investigated herein. The results show that photophysical and photochemical properties can be influenced by both size and shape of the nanoparticles. Physical characterization about the loading of nanoparticles was also looked into. Parameters such as the surface area, the number of surface atoms, the number of atoms as well as the number of nanoparticles loaded on the surface of the phthalocyanines were studied. The self-assembled monolayers formed by phthalocyanines on gold surfaces were studied using the X-ray photoelectron spectroscopy (XPS). The gold nanoparticles synthesized herein include both organic and water soluble, different capping agents (citrate, tetraammonium bromide (TAOBr) and cetrimethylammonium bromide (CTAB). The concentration of the gold nanoparticles was measured on the inductively coupled plasma (ICP) and their size and shape were obtained from the transmission electron microscopy (TEM) images. A cationic aluminium phthalocyanine and its conjugates were used for photoinactivation of bacteria and fungi. The results show significant reduction and higher activity in the presence of gold nanoparticles, especially nanorods. A small chapter in this work presents an attempted work on the binding of metallothionein protein with protophorphyrin (IX). The pH and concentration dependent binding studies were investigated
- Full Text:
- Authors: Mthethwa, Thandekile Phakamisiwe
- Date: 2015
- Subjects: Nanochemistry , Phthalocyanines , Photochemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4543 , http://hdl.handle.net/10962/d1017923
- Description: This thesis presents the synthesis of neutral and cationic metallophthalocyanines and their gold nanoparticles conjugates. The spectroscopic characterization of these compounds is presented herein. The studies presented in this work shows that the conjugation of gold nanoparticles influenced both photophysical and photochemical properties. Gold nanoparticles were found to enhance the singlet oxygen quantum yield while lowering the fluorescence quantum yields. This work also looks at the effect of anisotropic gold nanoparticles such as nanorods and bipyramids on the photophysical behaviour of the metallophthalocyanines. The effect of the size of the gold nanorods was investigated herein. The results show that photophysical and photochemical properties can be influenced by both size and shape of the nanoparticles. Physical characterization about the loading of nanoparticles was also looked into. Parameters such as the surface area, the number of surface atoms, the number of atoms as well as the number of nanoparticles loaded on the surface of the phthalocyanines were studied. The self-assembled monolayers formed by phthalocyanines on gold surfaces were studied using the X-ray photoelectron spectroscopy (XPS). The gold nanoparticles synthesized herein include both organic and water soluble, different capping agents (citrate, tetraammonium bromide (TAOBr) and cetrimethylammonium bromide (CTAB). The concentration of the gold nanoparticles was measured on the inductively coupled plasma (ICP) and their size and shape were obtained from the transmission electron microscopy (TEM) images. A cationic aluminium phthalocyanine and its conjugates were used for photoinactivation of bacteria and fungi. The results show significant reduction and higher activity in the presence of gold nanoparticles, especially nanorods. A small chapter in this work presents an attempted work on the binding of metallothionein protein with protophorphyrin (IX). The pH and concentration dependent binding studies were investigated
- Full Text:
Minding your own game : self-regulation and psychological momentum among golfers
- Authors: Kingma, Graham
- Date: 2015
- Subjects: Golf -- Strategic aspects , Golf -- Psychological aspects , Athletes , Self-control , Golfers -- Conduct of life
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3260 , http://hdl.handle.net/10962/d1017883
- Description: Psychological momentum (PM) is often regarded as an important phenomenon that influences athlete performance. Nevertheless, conceptualisations of PM are criticised for being speculative, vague and impractical for scientific inquiry. In contrast, self-regulation is a long-standing, well researched concept used to explain performance outcomes, yet not clearly integrated in current PM conceptualisations. Hence, this thesis explores self-regulation relative to PM. Golf was considered to be an appropriate context for the empirical inquiries on the basis that it serves as a metaphor for managing life’s challenges. Three studies were conducted. The first study entailed a systematic conceptual analysis of PM based on previous conceptualisations and studies in relevant scientific literature. Self-regulatory processes were identified among the key psychological mechanisms and moderators related to PM. The second study aimed to identify key self-regulation strategies in PM experiences among 16 golfers. A mixed method approach including novel “walk-along” and “think aloud” data collection techniques was used. An inductive thematic analysis yielded a comprehensive typology golfing strategies. Nevertheless, the study did not find consistent strategy patterns in positive or negative PM phases. The third study explored the self-regulation of identity (ego-regulation) in relation to PM phases. A staggered multiple-baseline single-case research methodology was used with five golfers (three professionals and two amateurs). Ego-regulation was manipulated through a mindfulness-based schema mode program tailored to golf (Mindfulness for Golf; MFG). Pre-, mid- and post-intervention data showed positive changes among the participants on two dimensions of PM as well as performance outcomes. Overall the results suggest that golfers use idiosyncratic self-regulation processes to facilitate performance, but these are not directly linked to PM phases. Nonetheless, there are promising indications that enhancing ego-regulation through the MFG program facilitates positive momentum among golfers. Based on the results of the studies in this thesis, and for the sake of scientific parsimony and pragmatism, it is recommended that self-regulation models incorporating motivation are used to explain momentum in athletic activity. In this view, PM has the function of describing, not influencing, goal-driven performance
- Full Text:
- Authors: Kingma, Graham
- Date: 2015
- Subjects: Golf -- Strategic aspects , Golf -- Psychological aspects , Athletes , Self-control , Golfers -- Conduct of life
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3260 , http://hdl.handle.net/10962/d1017883
- Description: Psychological momentum (PM) is often regarded as an important phenomenon that influences athlete performance. Nevertheless, conceptualisations of PM are criticised for being speculative, vague and impractical for scientific inquiry. In contrast, self-regulation is a long-standing, well researched concept used to explain performance outcomes, yet not clearly integrated in current PM conceptualisations. Hence, this thesis explores self-regulation relative to PM. Golf was considered to be an appropriate context for the empirical inquiries on the basis that it serves as a metaphor for managing life’s challenges. Three studies were conducted. The first study entailed a systematic conceptual analysis of PM based on previous conceptualisations and studies in relevant scientific literature. Self-regulatory processes were identified among the key psychological mechanisms and moderators related to PM. The second study aimed to identify key self-regulation strategies in PM experiences among 16 golfers. A mixed method approach including novel “walk-along” and “think aloud” data collection techniques was used. An inductive thematic analysis yielded a comprehensive typology golfing strategies. Nevertheless, the study did not find consistent strategy patterns in positive or negative PM phases. The third study explored the self-regulation of identity (ego-regulation) in relation to PM phases. A staggered multiple-baseline single-case research methodology was used with five golfers (three professionals and two amateurs). Ego-regulation was manipulated through a mindfulness-based schema mode program tailored to golf (Mindfulness for Golf; MFG). Pre-, mid- and post-intervention data showed positive changes among the participants on two dimensions of PM as well as performance outcomes. Overall the results suggest that golfers use idiosyncratic self-regulation processes to facilitate performance, but these are not directly linked to PM phases. Nonetheless, there are promising indications that enhancing ego-regulation through the MFG program facilitates positive momentum among golfers. Based on the results of the studies in this thesis, and for the sake of scientific parsimony and pragmatism, it is recommended that self-regulation models incorporating motivation are used to explain momentum in athletic activity. In this view, PM has the function of describing, not influencing, goal-driven performance
- Full Text:
Modification and application of the decentralised wastewater treatment technology for greywater treatment to reduce water needs
- Authors: Ngqwala, Nosiphiwe P
- Date: 2015
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/103714 , vital:32290
- Description: Expected release date-April 2017
- Full Text: false
- Authors: Ngqwala, Nosiphiwe P
- Date: 2015
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/103714 , vital:32290
- Description: Expected release date-April 2017
- Full Text: false
Molecular systematics and biology of two closely related blowflies : Lucilia sericata and Lucilia cuprina
- Authors: Williams, Kirstin Alexa
- Date: 2015
- Subjects: Lucilia sericata , Lucilia cuprina
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5934 , http://hdl.handle.net/10962/d1017812
- Description: The greenbottle blowflies, Lucilia sericata (Meigen, 1826) and Lucilia cuprina (Wiedemann, 1830) (Diptera: Calliphoridae) are very difficult to distinguish on the basis of their external morphology. The literature suggests that these two species may be interbreeding. Sequencing two nuclear (28S rRNA and Period) and one mitochondrial (COI) gene indicated that there has been an ancient hybridization event and that mtDNA of L. sericata has become fixed in a lineage of L. cuprina through mtDNA introgression, possibly involving Wolbachia infection. This has implications for identifications of these species based on mtDNA alone. No study has shown explicitly that hybrids of L. sericata and L. cuprina can be identified morphologically. Morphological characters used to identify L. sericata and L. cuprina were scored and tested using specimens of both species and known hybrids. Discriminant function analysis of the characters successfully separated the specimens into three unambiguous groups – L. sericata, L. cuprina and hybrids. This is the first evidence that hybrids of these two species can be identified from physical characteristics.Lucilia sericata and L. cuprina have medical, veterinary and forensic importance. Knowing their distribution in South Africa would allow more effective management and utilisation of these flies. Their predicted geographic distributions in South Africa were modelled using maximum entropy analysis of selected climatic variables. The most important environmental variables in modelling their distributions were magnitude of monthly rainfall and the magnitude of the monthly maximum temperature for L. sericata, and the seasonal variation in monthly mean humidity and magnitude of monthly rainfall for L. cuprina. Both species have a widespread distribution in South Africa and one therefore cannot identify specimens of these flies by locality of capture alone.Luciliinae is a diverse and geographically widespread subfamily containing four genera - Hemipyrellia, Lucilia, Dyscritomyia and Hypopygiopsis – that all contain parasitic species ranging from saprophages to obligate parasites. The phylogenetic relationships between these genera are unclear. The 28S rRNA, COI and Period genes of 14 species of Lucilia and Hemipyrellia were partially sequenced and analysed together with 11sequences from GenBank and the Barcode of Life Database (BOLD). Lucilia sericata and L. cuprina were shown to be sister-species. Three cases of paraphylly were identified within Lucilia that affects identification of these species using mtDNA alone. Hemipyrellia consistently caused Lucilia to be paraphyletic when it was included in analyses, so Hemipyrellia should be synonymized with Lucilia. The relationships of Dyscritomyia and Hypopygiopsis to Lucilia are unclear and further studies are required. No geographic pattern was found within the different forms of parasitism within this group, but the different degrees of parasitism were phylogenetically clustered.
- Full Text:
- Authors: Williams, Kirstin Alexa
- Date: 2015
- Subjects: Lucilia sericata , Lucilia cuprina
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5934 , http://hdl.handle.net/10962/d1017812
- Description: The greenbottle blowflies, Lucilia sericata (Meigen, 1826) and Lucilia cuprina (Wiedemann, 1830) (Diptera: Calliphoridae) are very difficult to distinguish on the basis of their external morphology. The literature suggests that these two species may be interbreeding. Sequencing two nuclear (28S rRNA and Period) and one mitochondrial (COI) gene indicated that there has been an ancient hybridization event and that mtDNA of L. sericata has become fixed in a lineage of L. cuprina through mtDNA introgression, possibly involving Wolbachia infection. This has implications for identifications of these species based on mtDNA alone. No study has shown explicitly that hybrids of L. sericata and L. cuprina can be identified morphologically. Morphological characters used to identify L. sericata and L. cuprina were scored and tested using specimens of both species and known hybrids. Discriminant function analysis of the characters successfully separated the specimens into three unambiguous groups – L. sericata, L. cuprina and hybrids. This is the first evidence that hybrids of these two species can be identified from physical characteristics.Lucilia sericata and L. cuprina have medical, veterinary and forensic importance. Knowing their distribution in South Africa would allow more effective management and utilisation of these flies. Their predicted geographic distributions in South Africa were modelled using maximum entropy analysis of selected climatic variables. The most important environmental variables in modelling their distributions were magnitude of monthly rainfall and the magnitude of the monthly maximum temperature for L. sericata, and the seasonal variation in monthly mean humidity and magnitude of monthly rainfall for L. cuprina. Both species have a widespread distribution in South Africa and one therefore cannot identify specimens of these flies by locality of capture alone.Luciliinae is a diverse and geographically widespread subfamily containing four genera - Hemipyrellia, Lucilia, Dyscritomyia and Hypopygiopsis – that all contain parasitic species ranging from saprophages to obligate parasites. The phylogenetic relationships between these genera are unclear. The 28S rRNA, COI and Period genes of 14 species of Lucilia and Hemipyrellia were partially sequenced and analysed together with 11sequences from GenBank and the Barcode of Life Database (BOLD). Lucilia sericata and L. cuprina were shown to be sister-species. Three cases of paraphylly were identified within Lucilia that affects identification of these species using mtDNA alone. Hemipyrellia consistently caused Lucilia to be paraphyletic when it was included in analyses, so Hemipyrellia should be synonymized with Lucilia. The relationships of Dyscritomyia and Hypopygiopsis to Lucilia are unclear and further studies are required. No geographic pattern was found within the different forms of parasitism within this group, but the different degrees of parasitism were phylogenetically clustered.
- Full Text:
Montane Wetlands of the South African Great Escarpment : plant communities and environmental drivers
- Authors: Janks, Matthew Richard
- Date: 2015
- Subjects: Mountain plants -- South Africa -- Eastern Cape , Wetland plants -- South Africa -- Eastern Cape , Wetland plants -- Effect of altitude on -- South Africa -- Eastern Cape , Wetland ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4274 , http://hdl.handle.net/10962/d1018917
- Description: Wetlands provide a number of valuable functions to both the surrounding environment and society. The anaerobic conditions created by flooding in wetlands provide a habitat that supports unique assemblages of plant life. High altitude wetlands are amongst the most species-rich in South Africa. They house a number of rare species and play a vital role in the supply of water to lower lying areas. These are some of the reasons that mountain wetlands are of high conservation value. A phytosociological study was undertaken on the high altitude wetlands of the Great Escarpment with the aim of classifying the plant communities and identifying the environmental drivers of plant community patterns within these ecosystems. Data collection was focused in the Eastern Cape and was supplemented with data from existing studies to gain a more complete understanding of the wetlands of the Great Escarpment of South Africa. Using the Braun-Blanquet approach, Hierarchical Cluster Analysis and Indicator Species Analysis; five broad wetland groups were identified, comprised of 33 individual plant communities and 81 indicator species. Multivariate analysis, including Canonical Correspondence Analysis revealed that the effects of altitude, such as temperature and rainfall, are the most significant large-scale drivers of vegetation patterns. Smaller scale drivers include wetness and soil nutrients including nitrogen, phosphorus, electrical conductivity, sodium, and organic content. The identification of indicator species served to reveal potentially important wetland species across different areas of the Great Escarpment. The effects of altitude on plant community patterns highlights the susceptibility of the high altitude specific communities to upward temperature zone shifts resulting from global warming. Other threats include livestock trampling, water extraction, and land use change for agricultural purposes. The relative absence of alien species in these wetlands gives an indication of their pristine condition and therefore their importance as a reference from which they may be monitored. A large proportion of the wetlands studied here occur outside protected areas, and given the rate of wetland loss in South Africa, it is important that continued effective land management is practiced to ensure that these ecosystems are conserved in the future .
- Full Text:
Montane Wetlands of the South African Great Escarpment : plant communities and environmental drivers
- Authors: Janks, Matthew Richard
- Date: 2015
- Subjects: Mountain plants -- South Africa -- Eastern Cape , Wetland plants -- South Africa -- Eastern Cape , Wetland plants -- Effect of altitude on -- South Africa -- Eastern Cape , Wetland ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4274 , http://hdl.handle.net/10962/d1018917
- Description: Wetlands provide a number of valuable functions to both the surrounding environment and society. The anaerobic conditions created by flooding in wetlands provide a habitat that supports unique assemblages of plant life. High altitude wetlands are amongst the most species-rich in South Africa. They house a number of rare species and play a vital role in the supply of water to lower lying areas. These are some of the reasons that mountain wetlands are of high conservation value. A phytosociological study was undertaken on the high altitude wetlands of the Great Escarpment with the aim of classifying the plant communities and identifying the environmental drivers of plant community patterns within these ecosystems. Data collection was focused in the Eastern Cape and was supplemented with data from existing studies to gain a more complete understanding of the wetlands of the Great Escarpment of South Africa. Using the Braun-Blanquet approach, Hierarchical Cluster Analysis and Indicator Species Analysis; five broad wetland groups were identified, comprised of 33 individual plant communities and 81 indicator species. Multivariate analysis, including Canonical Correspondence Analysis revealed that the effects of altitude, such as temperature and rainfall, are the most significant large-scale drivers of vegetation patterns. Smaller scale drivers include wetness and soil nutrients including nitrogen, phosphorus, electrical conductivity, sodium, and organic content. The identification of indicator species served to reveal potentially important wetland species across different areas of the Great Escarpment. The effects of altitude on plant community patterns highlights the susceptibility of the high altitude specific communities to upward temperature zone shifts resulting from global warming. Other threats include livestock trampling, water extraction, and land use change for agricultural purposes. The relative absence of alien species in these wetlands gives an indication of their pristine condition and therefore their importance as a reference from which they may be monitored. A large proportion of the wetlands studied here occur outside protected areas, and given the rate of wetland loss in South Africa, it is important that continued effective land management is practiced to ensure that these ecosystems are conserved in the future .
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Nanofiber immobilized cellulases and hemicellulases for fruit waste beneficiation
- Authors: Swart, Shanna
- Date: 2015
- Subjects: Agricultural wastes , Cellulase , Hemicellulose , Nanofibers , Electrospinning , Lignocellulose -- Biodegradation , Biomass conversion , Polysaccharides , Immobilized enzymes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4153 , http://hdl.handle.net/10962/d1017914
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- Authors: Swart, Shanna
- Date: 2015
- Subjects: Agricultural wastes , Cellulase , Hemicellulose , Nanofibers , Electrospinning , Lignocellulose -- Biodegradation , Biomass conversion , Polysaccharides , Immobilized enzymes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4153 , http://hdl.handle.net/10962/d1017914
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Natural resource use as a coping and adaptation strategy to floods of vulnerable populations in the Eastern Cape
- Sachikonye, Mwazvita Tapiwa Beatrice
- Authors: Sachikonye, Mwazvita Tapiwa Beatrice
- Date: 2015
- Subjects: Flood damage prevention -- South Africa -- Eastern Cape , Natural resources -- South Africa -- Eastern Cape , Land use -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Nature -- Effect of human beings on -- South Africa -- Eastern Cape , Human beings -- Effect of environment on -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4786 , http://hdl.handle.net/10962/d1018194
- Description: Many of the anticipated increased occurances of natural hazards are not only a consequence of climate change, but rather of rapid and widespread land cover change and the subsequent loss of the buffering capacity provided by healthy ecosystems against natural hazards. Unplanned and unmanaged developments in informal settlements limit government’s ability to mitigate and manage, pointing towards natural resources as being integral for vulnerable communities in developing countries to cope with and mitigate flood disasters. There is a lack of understanding on how natural resources contribute to resilience of vulnerable populations in the Eastern Cape and how they are impacted by these populations before, during and after a flood shock. There also exists a gap in knowledge on how natural resources can mitigate the physical impacts of flooding in South Africa, more so in the Eastern Cape province. Using household questionnaires and GIS techniques, the strategies that households used to recover from the October 2012-February 2013 flood shocks were investigated in informal settlements of three towns (Grahamstown, Port Alfred and Port St Johns). Within the vulnerability paradigm and the sustainable livelihood framework, the study also quantified and evaluated the relative contribution of natural resources to recovery strategies, and lastly, the study investigated how patterns of land use, state of natural vegetation and household topographical location exacerbated or diminished the physical impacts of flooding. This study found that natural resources contributed up to 70 percent to recovery of households from the flood shock, most of this being to reconstruction of housing structures after the flood, less so to economic recovery. It was also found that at a settlement scale the buffering effect of vegetation, although variable amongst settlements, was significant. Settlements that were dominated by dense bush and small trees experienced up to 46 percent less impacts on their property than those surrounded by bare gravel and impervious roofs with degraded environments. The main findings of the research show that natural resources reduce the vulnerability of households in informal settlements to flooding in two significant ways; by physically mitigating against damage to shelters and by also providing an emergency-net function that substitutes financial capital in households. Their inclusion in disaster management has the potential to encourage the sustainable livelihoods of the urban poor in the Eastern Cape
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- Authors: Sachikonye, Mwazvita Tapiwa Beatrice
- Date: 2015
- Subjects: Flood damage prevention -- South Africa -- Eastern Cape , Natural resources -- South Africa -- Eastern Cape , Land use -- South Africa -- Eastern Cape , Human ecology -- South Africa -- Eastern Cape , Nature -- Effect of human beings on -- South Africa -- Eastern Cape , Human beings -- Effect of environment on -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4786 , http://hdl.handle.net/10962/d1018194
- Description: Many of the anticipated increased occurances of natural hazards are not only a consequence of climate change, but rather of rapid and widespread land cover change and the subsequent loss of the buffering capacity provided by healthy ecosystems against natural hazards. Unplanned and unmanaged developments in informal settlements limit government’s ability to mitigate and manage, pointing towards natural resources as being integral for vulnerable communities in developing countries to cope with and mitigate flood disasters. There is a lack of understanding on how natural resources contribute to resilience of vulnerable populations in the Eastern Cape and how they are impacted by these populations before, during and after a flood shock. There also exists a gap in knowledge on how natural resources can mitigate the physical impacts of flooding in South Africa, more so in the Eastern Cape province. Using household questionnaires and GIS techniques, the strategies that households used to recover from the October 2012-February 2013 flood shocks were investigated in informal settlements of three towns (Grahamstown, Port Alfred and Port St Johns). Within the vulnerability paradigm and the sustainable livelihood framework, the study also quantified and evaluated the relative contribution of natural resources to recovery strategies, and lastly, the study investigated how patterns of land use, state of natural vegetation and household topographical location exacerbated or diminished the physical impacts of flooding. This study found that natural resources contributed up to 70 percent to recovery of households from the flood shock, most of this being to reconstruction of housing structures after the flood, less so to economic recovery. It was also found that at a settlement scale the buffering effect of vegetation, although variable amongst settlements, was significant. Settlements that were dominated by dense bush and small trees experienced up to 46 percent less impacts on their property than those surrounded by bare gravel and impervious roofs with degraded environments. The main findings of the research show that natural resources reduce the vulnerability of households in informal settlements to flooding in two significant ways; by physically mitigating against damage to shelters and by also providing an emergency-net function that substitutes financial capital in households. Their inclusion in disaster management has the potential to encourage the sustainable livelihoods of the urban poor in the Eastern Cape
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Negotiating historical continuities in contested terrain : a narrative-based reflection on the post-apartheid psychosocial legacies of conscription into the South African Defence Force
- Authors: Edlmann, Tessa Margaret
- Date: 2015
- Subjects: South Africa. National Defence Force , Draft -- South Africa -- History -- 20th century , Draft -- Psychological aspects , Masculinity -- South Africa , Sociology, Military -- South Africa , Whites -- Race identity -- South Africa , South Africa -- Politics and government -- 1948-1994 , Narrative inquiry (Research method)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2608 , http://hdl.handle.net/10962/d1012811
- Description: For a 25-year period during the apartheid era in South Africa, all school-leaving white men were issued with a compulsory call-up to national military service in the South African Defence Force. It is estimated that 600 000 men were conscripted between 1968 and 1993, undergoing military training and being deployed in Namibia, Angola and South Africa. The purpose of this system of military conscription was to support both the apartheid state’s role in the “Border War” in Namibia and Angola and the suppression of anti-apartheid resistance within South Africa. It formed part of the National Party’s strategy of a “total response” to what it perceived as the “total onslaught” of communism and African nationalism. While recruiting and training young white men was the focus of the apartheid government’s strategy, all of white South African society was caught up in supporting, contesting, avoiding and resisting this system in one way or another. Rather than being a purely military endeavour, conscription into the SADF therefore comprised a social and political system with wide-ranging ramifications. The 1994 democratic elections in South Africa heralded the advent of a very different political, social and economic system to what had gone before. The focus of this research is SADF conscripts’ narrations of identity in the contested narrative terrain of post-apartheid South Africa. The thesis begins with a contextual framing of the historical, social and political systems of which conscription was a part. Drawing on narrative psychology as a theoretical framework, the thesis explores discursive resources of whiteness, masculinities and perceptions of threat in conscripts’ narrations of identity, the construction of memory fields in narrating memories of war and possible trauma, and the notions of moral injury and moral repair in dealing with legacies of war. Using a narrative discursive approach, the thesis then reflects on historical temporal threads, and narrative patterns that emerge when analysing a range of texts about the psychosocial legacies of conscription, including interviews, research, memoirs, plays, media reports, video documentaries, blogs and photographic exhibitions. Throughout the thesis, conscripts’ and others’ accounts of conscription and its legacies are regarded as cultural texts. This serves as a means to highlight both contextual narrative negotiations and the narrative-discursive patterns of conscripts’ personal accounts of their identities in the post-apartheid narrative terrain. The original contribution of this research is the development of conceptual and theoretical framings of the post-apartheid legacies of conscription. Key to this has been the use of narrative-based approaches to highlight the narrative-discursive patterns, memory fields and negotiations of narrative terrains at work in texts that focus on various aspects of conscription and its ongoing aftereffects. The concept of temporal threads has been developed to account for the emergence and shifts in these patterns over time. Existing narrative-discursive theory has formed the basis for conscripts’ negotiations of identity being identified as acts of narrative reinforcement and narrative repair. The thesis concludes with reflections on the future possibilities for articulating and supporting narrative repair that enables a shift away from historical discursive laagers and a reconfiguration of the narrative terrain within which conscripts narrate their identities. , Also known as: Edlmann, Theresa
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- Authors: Edlmann, Tessa Margaret
- Date: 2015
- Subjects: South Africa. National Defence Force , Draft -- South Africa -- History -- 20th century , Draft -- Psychological aspects , Masculinity -- South Africa , Sociology, Military -- South Africa , Whites -- Race identity -- South Africa , South Africa -- Politics and government -- 1948-1994 , Narrative inquiry (Research method)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2608 , http://hdl.handle.net/10962/d1012811
- Description: For a 25-year period during the apartheid era in South Africa, all school-leaving white men were issued with a compulsory call-up to national military service in the South African Defence Force. It is estimated that 600 000 men were conscripted between 1968 and 1993, undergoing military training and being deployed in Namibia, Angola and South Africa. The purpose of this system of military conscription was to support both the apartheid state’s role in the “Border War” in Namibia and Angola and the suppression of anti-apartheid resistance within South Africa. It formed part of the National Party’s strategy of a “total response” to what it perceived as the “total onslaught” of communism and African nationalism. While recruiting and training young white men was the focus of the apartheid government’s strategy, all of white South African society was caught up in supporting, contesting, avoiding and resisting this system in one way or another. Rather than being a purely military endeavour, conscription into the SADF therefore comprised a social and political system with wide-ranging ramifications. The 1994 democratic elections in South Africa heralded the advent of a very different political, social and economic system to what had gone before. The focus of this research is SADF conscripts’ narrations of identity in the contested narrative terrain of post-apartheid South Africa. The thesis begins with a contextual framing of the historical, social and political systems of which conscription was a part. Drawing on narrative psychology as a theoretical framework, the thesis explores discursive resources of whiteness, masculinities and perceptions of threat in conscripts’ narrations of identity, the construction of memory fields in narrating memories of war and possible trauma, and the notions of moral injury and moral repair in dealing with legacies of war. Using a narrative discursive approach, the thesis then reflects on historical temporal threads, and narrative patterns that emerge when analysing a range of texts about the psychosocial legacies of conscription, including interviews, research, memoirs, plays, media reports, video documentaries, blogs and photographic exhibitions. Throughout the thesis, conscripts’ and others’ accounts of conscription and its legacies are regarded as cultural texts. This serves as a means to highlight both contextual narrative negotiations and the narrative-discursive patterns of conscripts’ personal accounts of their identities in the post-apartheid narrative terrain. The original contribution of this research is the development of conceptual and theoretical framings of the post-apartheid legacies of conscription. Key to this has been the use of narrative-based approaches to highlight the narrative-discursive patterns, memory fields and negotiations of narrative terrains at work in texts that focus on various aspects of conscription and its ongoing aftereffects. The concept of temporal threads has been developed to account for the emergence and shifts in these patterns over time. Existing narrative-discursive theory has formed the basis for conscripts’ negotiations of identity being identified as acts of narrative reinforcement and narrative repair. The thesis concludes with reflections on the future possibilities for articulating and supporting narrative repair that enables a shift away from historical discursive laagers and a reconfiguration of the narrative terrain within which conscripts narrate their identities. , Also known as: Edlmann, Theresa
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Network simulation for professional audio networks
- Authors: Otten, Fred
- Date: 2015
- Subjects: Sound engineers , Ethernet (Local area network system) , Computer networks , Computer simulation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4713 , http://hdl.handle.net/10962/d1017935
- Description: Audio Engineers are required to design and deploy large multi-channel sound systems which meet a set of requirements and use networking technologies such as Firewire and Ethernet AVB. Bandwidth utilisation and parameter groupings are among the factors which need to be considered in these designs. An implementation of an extensible, generic simulation framework would allow audio engineers to easily compare protocols and networking technologies and get near real time responses with regards to bandwidth utilisation. Our hypothesis is that an application-level capability can be developed which uses a network simulation framework to enable this process and enhances the audio engineer’s experience of designing and configuring a network. This thesis presents a new, extensible simulation framework which can be utilised to simulate professional audio networks. This framework is utilised to develop an application - AudioNetSim - based on the requirements of an audio engineer. The thesis describes the AudioNetSim models and implementations for Ethernet AVB, Firewire and the AES- 64 control protocol. AudioNetSim enables bandwidth usage determination for any network configuration and connection scenario and is used to compare Firewire and Ethernet AVB bandwidth utilisation. It also applies graph theory to the circular join problem and provides a solution to detect circular joins.
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- Authors: Otten, Fred
- Date: 2015
- Subjects: Sound engineers , Ethernet (Local area network system) , Computer networks , Computer simulation
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4713 , http://hdl.handle.net/10962/d1017935
- Description: Audio Engineers are required to design and deploy large multi-channel sound systems which meet a set of requirements and use networking technologies such as Firewire and Ethernet AVB. Bandwidth utilisation and parameter groupings are among the factors which need to be considered in these designs. An implementation of an extensible, generic simulation framework would allow audio engineers to easily compare protocols and networking technologies and get near real time responses with regards to bandwidth utilisation. Our hypothesis is that an application-level capability can be developed which uses a network simulation framework to enable this process and enhances the audio engineer’s experience of designing and configuring a network. This thesis presents a new, extensible simulation framework which can be utilised to simulate professional audio networks. This framework is utilised to develop an application - AudioNetSim - based on the requirements of an audio engineer. The thesis describes the AudioNetSim models and implementations for Ethernet AVB, Firewire and the AES- 64 control protocol. AudioNetSim enables bandwidth usage determination for any network configuration and connection scenario and is used to compare Firewire and Ethernet AVB bandwidth utilisation. It also applies graph theory to the circular join problem and provides a solution to detect circular joins.
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