Evidence for a biological control-induced regime shift between floating and submerged invasive plant dominance in South Africa
- Authors: Strange, Emily Frances
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/32448 , vital:24044
- Description: South Africa has a long history battling the establishment and spread of invasive floating macrophytes. The negative consequences of these are costly both economically and ecologically. They form dense mats on the water's surface that deplete resources such as light and oxygen to the submerged community, which creates anoxic conditions, reduces biodiversity and limits access to freshwater. The past thirty years of South African invasive plant research and the implementation of nationwide biological control programmes has led to widespread control of these species in many degraded systems. Such initiatives are aimed at restoring access to potable freshwater and increasing native biodiversity. However, in recent years, where there has been a decline in floating invasive plant populations, an increase in the establishment and spread of submerged invasive plant species has been observed. Species such as Brazilian waterweed (Egeria densa (Planch.) (Hydrocharitaceae)) and Eurasian watermilfoil (Myriophyllum spicatum (L.) (Haloragaceae)) have been recorded in South African freshwater systems, posing significant threats to aquatic ecosystems. This thesis proposes that the biological control of floating invasive plants, which occurs in numerous dams and rivers nationwide, is the catalyst of a regime shift from floating invasive to submerged invasive plant dominance. Regime shifts are large and often sudden changes in the key structure and functioning of ecosystems, and studies into their occurrence and driving mechanisms broadens understanding of community structures and can guide effective resource management. In order to explore the existence of this new regime shift, a multi-platform approach using controlled experiments and ecological modelling techniques was employed. A model system was created consisting of a floating invasive (Pistia stratiotes L. (Araceae)), a submerged invasive (E. densa) and an ecologically analogous submerged native plant species (Lagarosiphon major (Ridl.) Moss (Hydrocharitaceae)). A suite of experiments was conducted to explore the interactions between the floating and submerged plants under varying regimes of floating plant biological control and levels of nutrient loading. These experiments revealed a competitive advantage of the invasive E. densa over the native L. major that increased by 86% under heavy nutrient loading. The relative growth rate and accumulated biomass of E. densa was significantly higher for plants grown in the presence of biologically controlled P. stratiotes (compared to insect free plants). This demonstrates a high capacity for the invasive E. densa to capitalise on resources made newly available through the biological control of the floating plants. In contrast, the native L. major fared poorly when grown in the presence of the floating P. stratiotes, regardless of applied biological control measures. The experimental observations were then used to parameterise a mathematical model, built to provide a holistic understanding of the individually assessed interactions which work together as the driving mechanisms underpinning the newly identified regime shift. This thesis utilised a multi-platform approach to build the first body of evidence in support of a newly recognised regime shift between floating invasive and submerged invasive plant dominance, as driven by biological control. The results indicate that a reduction in the nutrient loading of South Africa's freshwater systems will reduce negative impacts of submerged invasive macrophytes, whilst increasing system resilience against future invasion. The evidence presented has the potential to better inform management of South Africa's freshwater systems and highlights the importance of integrating multi-trophic interactions when considering future invasive plant management. This research also opens up a multitude of possibilities for studies into submerged plant invasion mechanisms and resilience of native macrophyte communities in South Africa, and further afield.
- Full Text:
- Authors: Strange, Emily Frances
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/32448 , vital:24044
- Description: South Africa has a long history battling the establishment and spread of invasive floating macrophytes. The negative consequences of these are costly both economically and ecologically. They form dense mats on the water's surface that deplete resources such as light and oxygen to the submerged community, which creates anoxic conditions, reduces biodiversity and limits access to freshwater. The past thirty years of South African invasive plant research and the implementation of nationwide biological control programmes has led to widespread control of these species in many degraded systems. Such initiatives are aimed at restoring access to potable freshwater and increasing native biodiversity. However, in recent years, where there has been a decline in floating invasive plant populations, an increase in the establishment and spread of submerged invasive plant species has been observed. Species such as Brazilian waterweed (Egeria densa (Planch.) (Hydrocharitaceae)) and Eurasian watermilfoil (Myriophyllum spicatum (L.) (Haloragaceae)) have been recorded in South African freshwater systems, posing significant threats to aquatic ecosystems. This thesis proposes that the biological control of floating invasive plants, which occurs in numerous dams and rivers nationwide, is the catalyst of a regime shift from floating invasive to submerged invasive plant dominance. Regime shifts are large and often sudden changes in the key structure and functioning of ecosystems, and studies into their occurrence and driving mechanisms broadens understanding of community structures and can guide effective resource management. In order to explore the existence of this new regime shift, a multi-platform approach using controlled experiments and ecological modelling techniques was employed. A model system was created consisting of a floating invasive (Pistia stratiotes L. (Araceae)), a submerged invasive (E. densa) and an ecologically analogous submerged native plant species (Lagarosiphon major (Ridl.) Moss (Hydrocharitaceae)). A suite of experiments was conducted to explore the interactions between the floating and submerged plants under varying regimes of floating plant biological control and levels of nutrient loading. These experiments revealed a competitive advantage of the invasive E. densa over the native L. major that increased by 86% under heavy nutrient loading. The relative growth rate and accumulated biomass of E. densa was significantly higher for plants grown in the presence of biologically controlled P. stratiotes (compared to insect free plants). This demonstrates a high capacity for the invasive E. densa to capitalise on resources made newly available through the biological control of the floating plants. In contrast, the native L. major fared poorly when grown in the presence of the floating P. stratiotes, regardless of applied biological control measures. The experimental observations were then used to parameterise a mathematical model, built to provide a holistic understanding of the individually assessed interactions which work together as the driving mechanisms underpinning the newly identified regime shift. This thesis utilised a multi-platform approach to build the first body of evidence in support of a newly recognised regime shift between floating invasive and submerged invasive plant dominance, as driven by biological control. The results indicate that a reduction in the nutrient loading of South Africa's freshwater systems will reduce negative impacts of submerged invasive macrophytes, whilst increasing system resilience against future invasion. The evidence presented has the potential to better inform management of South Africa's freshwater systems and highlights the importance of integrating multi-trophic interactions when considering future invasive plant management. This research also opens up a multitude of possibilities for studies into submerged plant invasion mechanisms and resilience of native macrophyte communities in South Africa, and further afield.
- Full Text:
How do social and personal identity, sense of place, connectedness to nature and environmental understanding influence the implementation of collective, large-scale biodiversity stewardship initiatives in South Africa?
- Authors: Potts, Tracey Ann
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3663 , vital:20534
- Description: Biodiversity stewardship is a mechanism that is used to conserve high value biodiversity assets. Biodiversity stewardship programmes focus on areas that are under immediate threat from development or under medium to long term threat from degradation or transformation that will result in habitat loss. Biodiversity stewardship provides a solution to the resource crisis being faced by many state and provincial conservation agencies, NGO’s (Non-Governmental Organisations) and PBO’s (Public Benefit Organisations) in that it facilitates the declaration, and the subsequent improved conservation management, of private or communally owned land whilst still retaining the existing tenure. The rate of habitat loss can often be slowed, or even reversed, by proactively securing these areas and facilitating management decision-making with a focus on biodiversity outcomes without the capital investment required by the State to purchase the land. In return for conservation management actions, certain land-use restrictions and the associated opportunity costs, the State offers a suite of incentives and benefits that are, where possible, tailored to meet the needs of the landowner. Particular regions of South Africa lend themselves well to the development of biodiversity stewardship initiatives which are designed to secure ecological processes and ecosystems across a landscape or an ecological feature at scales of tens of thousands of hectares. When developing landscape level biodiversity stewardship initiatives, negotiations tend to be focussed on groups of landowners. This requires collaboration and the collective alignment of natural resource management decision-making and conservation actions amongst neighbours. Gaining a better understanding of how the social constructs of ecological understanding, place attachment, connectedness to nature, occupational identity and social and personal identity influence decision-making, behaviour and group structure is a critically important factor when developing a tool to predict the likelihood of landowners to collectively commit to long-term, legally binding biodiversity stewardship programmes. The overarching hypothesis was that the social constructs listed above influence group dynamics within the context of collective pro-conservation behaviour. Social dynamics associated with large-scale biodiversity stewardship initiatives become complex when multiple landowners are involved. Could social cohesion and group culture be influenced by aspects of identity and do these in turn develop into barriers or motivators to coordinated and sustained conservation efforts? Further influences on the successful implementation of landscape scale biodiversity stewardship initiatives could include ecological understanding, connectedness to nature and place attachment. Structured interviews were held with the landowners engaged in two separate large-scale biodiversity stewardship sites, the Compassberg Protected Environment and the Baviaanskloof Hartland, in the Eastern Cape Province of South Africa. The interviews were followed up with surveys containing psychometric scales related to the influence of ecological understanding, place attachment, connectedness to nature and aspects of identity on commitment to collective long-term, large-scale biodiversity stewardship initiatives. The results from a set of non-parametric (exact) Wilcoxon rank-sum tests showed that scores on the new ecological paradigm scale and the place attachment scale latent variables were significantly different at the two study sites, at the 10% level of significance. Demographic differences between the two study sites influenced group dynamics, collective decision-making and commitment. The relationship between the latent variables (the five psychometric scales measured) and the ancillary variables (the demographic data describing the respondents) cannot be considered conclusive; however they do provide relatively useful insights into the development of a scale or tool to measure conservation opportunity. The thesis concludes with a proposed conservation opportunity assessment tool that can be utilised alongside the existing, well refined, conservation priority assessment tools to assist in decision-making when planning large, landscape scale biodiversity stewardship initiatives in South Africa.
- Full Text:
- Authors: Potts, Tracey Ann
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/3663 , vital:20534
- Description: Biodiversity stewardship is a mechanism that is used to conserve high value biodiversity assets. Biodiversity stewardship programmes focus on areas that are under immediate threat from development or under medium to long term threat from degradation or transformation that will result in habitat loss. Biodiversity stewardship provides a solution to the resource crisis being faced by many state and provincial conservation agencies, NGO’s (Non-Governmental Organisations) and PBO’s (Public Benefit Organisations) in that it facilitates the declaration, and the subsequent improved conservation management, of private or communally owned land whilst still retaining the existing tenure. The rate of habitat loss can often be slowed, or even reversed, by proactively securing these areas and facilitating management decision-making with a focus on biodiversity outcomes without the capital investment required by the State to purchase the land. In return for conservation management actions, certain land-use restrictions and the associated opportunity costs, the State offers a suite of incentives and benefits that are, where possible, tailored to meet the needs of the landowner. Particular regions of South Africa lend themselves well to the development of biodiversity stewardship initiatives which are designed to secure ecological processes and ecosystems across a landscape or an ecological feature at scales of tens of thousands of hectares. When developing landscape level biodiversity stewardship initiatives, negotiations tend to be focussed on groups of landowners. This requires collaboration and the collective alignment of natural resource management decision-making and conservation actions amongst neighbours. Gaining a better understanding of how the social constructs of ecological understanding, place attachment, connectedness to nature, occupational identity and social and personal identity influence decision-making, behaviour and group structure is a critically important factor when developing a tool to predict the likelihood of landowners to collectively commit to long-term, legally binding biodiversity stewardship programmes. The overarching hypothesis was that the social constructs listed above influence group dynamics within the context of collective pro-conservation behaviour. Social dynamics associated with large-scale biodiversity stewardship initiatives become complex when multiple landowners are involved. Could social cohesion and group culture be influenced by aspects of identity and do these in turn develop into barriers or motivators to coordinated and sustained conservation efforts? Further influences on the successful implementation of landscape scale biodiversity stewardship initiatives could include ecological understanding, connectedness to nature and place attachment. Structured interviews were held with the landowners engaged in two separate large-scale biodiversity stewardship sites, the Compassberg Protected Environment and the Baviaanskloof Hartland, in the Eastern Cape Province of South Africa. The interviews were followed up with surveys containing psychometric scales related to the influence of ecological understanding, place attachment, connectedness to nature and aspects of identity on commitment to collective long-term, large-scale biodiversity stewardship initiatives. The results from a set of non-parametric (exact) Wilcoxon rank-sum tests showed that scores on the new ecological paradigm scale and the place attachment scale latent variables were significantly different at the two study sites, at the 10% level of significance. Demographic differences between the two study sites influenced group dynamics, collective decision-making and commitment. The relationship between the latent variables (the five psychometric scales measured) and the ancillary variables (the demographic data describing the respondents) cannot be considered conclusive; however they do provide relatively useful insights into the development of a scale or tool to measure conservation opportunity. The thesis concludes with a proposed conservation opportunity assessment tool that can be utilised alongside the existing, well refined, conservation priority assessment tools to assist in decision-making when planning large, landscape scale biodiversity stewardship initiatives in South Africa.
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The experiences of isiMpondo speakers in learning standard isiXhosa through the formal education system : an exploratory study at a school in the Bizana district of the Eastern Cape
- Authors: Maqam, Eslinah Zodwa
- Date: 2015
- Subjects: Language and teaching -- South Africa -- Eastern Cape -- Bizana , Native language and education , Language policy -- South Africa -- Eastern Cape -- Bizana
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3652 , http://hdl.handle.net/10962/d1017893
- Description: This study investigates the experiences of isiMpondo speakers in learning standard language through the formal education system. The sociolinguistic factors such as attitudes, language policies and language use in multilingual societies are taken into considerations. The children of non-standard language speakers such as those who speak dialects like isiMpondo have to use another language in their early years in the school system. It is articulated that the isiMpondo that the child brings to the school from the environment is not accommodated simply because it is a non-standard language; whereas the language that is used in the classroom situation is the isiXhosa variety which is a standard one. The research findings show that isiMpondo impacts on learner’s education directly because they lose marks during the course of the year and during examination times if they use it. The study concludes with a recommendation that educators should honour the seven roles of educators by appropriate norms and standards. Some approaches to teaching have been suggested to be used by teachers with regard to inclusivity, as it recognises diversity, and values the following: the uniqueness of the individuals, the experiences, abilities, cultural and language backgrounds of each individual. All in all it seeks to meet the needs of the individual learner by creating a non-discriminatory teaching and learning environment.
- Full Text:
- Authors: Maqam, Eslinah Zodwa
- Date: 2015
- Subjects: Language and teaching -- South Africa -- Eastern Cape -- Bizana , Native language and education , Language policy -- South Africa -- Eastern Cape -- Bizana
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3652 , http://hdl.handle.net/10962/d1017893
- Description: This study investigates the experiences of isiMpondo speakers in learning standard language through the formal education system. The sociolinguistic factors such as attitudes, language policies and language use in multilingual societies are taken into considerations. The children of non-standard language speakers such as those who speak dialects like isiMpondo have to use another language in their early years in the school system. It is articulated that the isiMpondo that the child brings to the school from the environment is not accommodated simply because it is a non-standard language; whereas the language that is used in the classroom situation is the isiXhosa variety which is a standard one. The research findings show that isiMpondo impacts on learner’s education directly because they lose marks during the course of the year and during examination times if they use it. The study concludes with a recommendation that educators should honour the seven roles of educators by appropriate norms and standards. Some approaches to teaching have been suggested to be used by teachers with regard to inclusivity, as it recognises diversity, and values the following: the uniqueness of the individuals, the experiences, abilities, cultural and language backgrounds of each individual. All in all it seeks to meet the needs of the individual learner by creating a non-discriminatory teaching and learning environment.
- Full Text:
Teachers’ understanding and implementation of inclusive education in an Eastern Cape primary school
- Authors: Mcconnachie, Karola
- Date: 2014
- Subjects: Inclusive education -- South Africa , Special education -- South Africa , Education (Primary) -- Government policy -- South Africa , Alcoholism -- Social aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1984 , http://hdl.handle.net/10962/d1013150
- Description: Since 2001 the South African Department of Basic Education has been working towards implementing Inclusive Education over a twenty year period. This is in accordance with international trends in education. This study set out to investigate the implementation of Inclusive Education in a South African context by conducting a case study at an Eastern Cape no‐fee‐paying primary school. It looked at how the government policy, as set out in Education White Paper 6 (EWP6) (DoE, 2001), is understood and being implemented by teachers at the Welcome Primary school. The study further investigated the introduction of the National Strategy on Screening, Identification, Assessment and Support (SIAS strategy) (DoE, 2008a) to gain insight into how teachers identify and assess barriers to learning in an ordinary primary school. In addition it looked at emerging factors that could impact on the implementation of this policy. With 16 years teaching experience in ordinary and private schools and 19 years experience in a special needs school as a teacher, head of department and then principal, I have personal experience of the crisis in the Eastern Cape Department of Basic Education. This awareness provided the impetus and interest in researching Inclusive Education policy implementation. It is my view that only when we begin to grapple with the problems right at the source of the education crisis within the majority of the no‐fee‐paying schools that informed decisions about policy and policy implementation can be made. As I am able to understand and converse in isiXhosa, I was able to observe and experience the implementation of EWP6 and the SIAS strategy in a school that is an isiXhosa‐medium ordinary primary school and similar to the majority of ordinary public schools in the district. A qualitative research approach based within an interpretive paradigm using the case study method was used for this study. Semi‐structured interviews, detailed field notes as well as documents generated by meetings and education conferences helped me to investigate and refine my research goals. The research found that the implementation of EWP6 and the SIAS strategy posed a major challenge for the Department of Basic Education, and highlighted the significant gap between ordinary primary schools and special needs schools. However, the fact that there is a partial engagement with the process of providing inclusive education, does present some measure of hope for a better future for those learners that have experienced the injustice of exclusion from education and society. The Eastern Cape Department of Basic Education will have to ‘catch up’ to other provinces in its delivery of every child’s constitutional right to education in an inclusive school environment. Factors emerged from the study that showed that the assessment of learners’ barriers to learning with the resultant support needs was a relatively new concept, as teachers tended to rely on traditional classroom tests and simple informal classroom assessments to assess the learners. Teachers expressed a good verbal knowledge of learners with support needs but found it very challenging to put this verbal knowledge into a written document. In addition there was inadequate support from the District Based Support Team to implement the SIAS strategy. This study showed that the medical model of assessment was still being adhered to in the research district with little evidence of a move to a social model of assessment in terms of the SIAS strategy. In addition, factors emerged indicating the serious impact that alcohol abuse has on children and the society in which they live. The evidence of increasing numbers of children with Fetal Alcohol Spectrum Disorder (FASD) in a single educational district is a matter of grave concern from an educational and financial perspective. It is my contention that this is a matter of national urgency and that the Department of Basic Education must confront the escalating problem of alcohol abuse and the resultant challenges of a large number of learners with serious barriers to learning that need to be included in the education system.
- Full Text:
- Authors: Mcconnachie, Karola
- Date: 2014
- Subjects: Inclusive education -- South Africa , Special education -- South Africa , Education (Primary) -- Government policy -- South Africa , Alcoholism -- Social aspects -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1984 , http://hdl.handle.net/10962/d1013150
- Description: Since 2001 the South African Department of Basic Education has been working towards implementing Inclusive Education over a twenty year period. This is in accordance with international trends in education. This study set out to investigate the implementation of Inclusive Education in a South African context by conducting a case study at an Eastern Cape no‐fee‐paying primary school. It looked at how the government policy, as set out in Education White Paper 6 (EWP6) (DoE, 2001), is understood and being implemented by teachers at the Welcome Primary school. The study further investigated the introduction of the National Strategy on Screening, Identification, Assessment and Support (SIAS strategy) (DoE, 2008a) to gain insight into how teachers identify and assess barriers to learning in an ordinary primary school. In addition it looked at emerging factors that could impact on the implementation of this policy. With 16 years teaching experience in ordinary and private schools and 19 years experience in a special needs school as a teacher, head of department and then principal, I have personal experience of the crisis in the Eastern Cape Department of Basic Education. This awareness provided the impetus and interest in researching Inclusive Education policy implementation. It is my view that only when we begin to grapple with the problems right at the source of the education crisis within the majority of the no‐fee‐paying schools that informed decisions about policy and policy implementation can be made. As I am able to understand and converse in isiXhosa, I was able to observe and experience the implementation of EWP6 and the SIAS strategy in a school that is an isiXhosa‐medium ordinary primary school and similar to the majority of ordinary public schools in the district. A qualitative research approach based within an interpretive paradigm using the case study method was used for this study. Semi‐structured interviews, detailed field notes as well as documents generated by meetings and education conferences helped me to investigate and refine my research goals. The research found that the implementation of EWP6 and the SIAS strategy posed a major challenge for the Department of Basic Education, and highlighted the significant gap between ordinary primary schools and special needs schools. However, the fact that there is a partial engagement with the process of providing inclusive education, does present some measure of hope for a better future for those learners that have experienced the injustice of exclusion from education and society. The Eastern Cape Department of Basic Education will have to ‘catch up’ to other provinces in its delivery of every child’s constitutional right to education in an inclusive school environment. Factors emerged from the study that showed that the assessment of learners’ barriers to learning with the resultant support needs was a relatively new concept, as teachers tended to rely on traditional classroom tests and simple informal classroom assessments to assess the learners. Teachers expressed a good verbal knowledge of learners with support needs but found it very challenging to put this verbal knowledge into a written document. In addition there was inadequate support from the District Based Support Team to implement the SIAS strategy. This study showed that the medical model of assessment was still being adhered to in the research district with little evidence of a move to a social model of assessment in terms of the SIAS strategy. In addition, factors emerged indicating the serious impact that alcohol abuse has on children and the society in which they live. The evidence of increasing numbers of children with Fetal Alcohol Spectrum Disorder (FASD) in a single educational district is a matter of grave concern from an educational and financial perspective. It is my contention that this is a matter of national urgency and that the Department of Basic Education must confront the escalating problem of alcohol abuse and the resultant challenges of a large number of learners with serious barriers to learning that need to be included in the education system.
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Thermoluminescence of secondary glow peaks in carbon-doped aluminium oxide
- Authors: Seneza, Cleophace
- Date: 2014
- Subjects: Thermoluminescence , Aluminum oxide , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5537 , http://hdl.handle.net/10962/d1013053
- Description: Carbon-doped aluminium oxide, α-Al₂O₃ : C, is a highly sensitive luminescence dosimeter. The high sensitivity of α-Al₂O₃ : C has been attributed to large concentrations of oxygen vacancies, F and F⁺ centres, induced in the material during its preparation. The material is prepared in a highly reducing atmosphere in the presence of carbon. In the luminescence process, electrons are trapped in F-centre defects as a result of irradiation of the material. Thermal or optical release of trapped electrons leads to emission of light, thermoluminescence (TL) or optically stimulated light (OSL) respectively. The thermoluminescence technique is used to study point defects involved in luminescence of α-Al₂O₃ : C. A glow curve of α-Al₂O₃ : C, generally, shows three peaks; the main dosimetric peak of high intensity (peak II) and two other peaks of lower intensity called secondary glow peaks (peaks I and III). The overall aim of our work was to study the TL mechanisms responsible for secondary glow peaks in α-Al₂O₃ : C. The dynamics of charge movement between centres during the TL process was studied. The phototransferred thermoluminescence (PTTL) from secondary glow peaks was also studied. The kinetic analysis of TL from secondary peaks has shown that the activation energy of peak I is 0.7 eV and that of peak III, 1.2 eV. The frequency factor, the frequency at which an electron attempts to escape a trap, was found near the range of the Debye vibration frequency. Values of the activation energy are consistent within a variety of methods used. The two peaks follow first order kinetics as confirmed by the TM-Tstop method. A linear dependence of TL from peak I on dose is observed at various doses from 0.5 to 2.5 Gy. The peak position for peak I was also independent on dose, further confirmation that peak I is of first order kinetics. Peak I suffers from thermal fading with storage with a half-life of about 120 s. The dependence of TL intensity for peak I increased as a function of heating rate from 0.2 to 6ºCs⁻¹. In contrast to the TL intensity for peak I, the intensity of TL for peak III decreases with an increase of heating rate from 0.2 to 6ºCs⁻¹. This is evidence of thermal quenching for peak III. Parameters W = 1.48 ± 0:10 eV and C = 4 x 10¹³ of thermal quenching were calculated from peak III intensities at different heating rates. Thermal cleaning of peak III and the glow curve deconvolution methods confirmed that the main peak is actually overlapped by a small peak (labeled peak IIA). The kinetic analysis of peak IIA showed that it is of first order kinetics and that its activation energy is 1:0 eV. In addition, the peak IIA is affected by thermal quenching. Another secondary peak appears at 422ºC (peak IV). However, the kinetic analysis of TL from peak IV was not studied because its intensity is not well defined. A heating rate of 0.4ºCs⁻¹ was used after a dose of 3 Gy in kinetic analysis of peaks IIA and III. The study of the PTTL showed that peaks I and II were regenerated under PTTL but peak III was not. Various effects of the PTTL for peaks I and II for different preheating temperatures in different samples were observed. The effect of annealing at 900ºC for 15 minutes between measurements following each illumination time was studied. The effect of dose on secondary peaks was also studied in this work. The kinetic analysis of the PTTL intensity for peak I showed that its activation energy is 0.7 eV, consistent with the activation energy of the normal TL for peak I. The PTTL intensity from peak I fades rapidly with storage compared with the thermal fading from peak I of the normal TL. The PTTL intensity for peak I decreases as a function of heating rate. This decrease was attributed to thermal quenching. Thermal quenching was not observed in the case of the normal TL intensity. The cause of this contrast requires further study.
- Full Text:
- Authors: Seneza, Cleophace
- Date: 2014
- Subjects: Thermoluminescence , Aluminum oxide , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5537 , http://hdl.handle.net/10962/d1013053
- Description: Carbon-doped aluminium oxide, α-Al₂O₃ : C, is a highly sensitive luminescence dosimeter. The high sensitivity of α-Al₂O₃ : C has been attributed to large concentrations of oxygen vacancies, F and F⁺ centres, induced in the material during its preparation. The material is prepared in a highly reducing atmosphere in the presence of carbon. In the luminescence process, electrons are trapped in F-centre defects as a result of irradiation of the material. Thermal or optical release of trapped electrons leads to emission of light, thermoluminescence (TL) or optically stimulated light (OSL) respectively. The thermoluminescence technique is used to study point defects involved in luminescence of α-Al₂O₃ : C. A glow curve of α-Al₂O₃ : C, generally, shows three peaks; the main dosimetric peak of high intensity (peak II) and two other peaks of lower intensity called secondary glow peaks (peaks I and III). The overall aim of our work was to study the TL mechanisms responsible for secondary glow peaks in α-Al₂O₃ : C. The dynamics of charge movement between centres during the TL process was studied. The phototransferred thermoluminescence (PTTL) from secondary glow peaks was also studied. The kinetic analysis of TL from secondary peaks has shown that the activation energy of peak I is 0.7 eV and that of peak III, 1.2 eV. The frequency factor, the frequency at which an electron attempts to escape a trap, was found near the range of the Debye vibration frequency. Values of the activation energy are consistent within a variety of methods used. The two peaks follow first order kinetics as confirmed by the TM-Tstop method. A linear dependence of TL from peak I on dose is observed at various doses from 0.5 to 2.5 Gy. The peak position for peak I was also independent on dose, further confirmation that peak I is of first order kinetics. Peak I suffers from thermal fading with storage with a half-life of about 120 s. The dependence of TL intensity for peak I increased as a function of heating rate from 0.2 to 6ºCs⁻¹. In contrast to the TL intensity for peak I, the intensity of TL for peak III decreases with an increase of heating rate from 0.2 to 6ºCs⁻¹. This is evidence of thermal quenching for peak III. Parameters W = 1.48 ± 0:10 eV and C = 4 x 10¹³ of thermal quenching were calculated from peak III intensities at different heating rates. Thermal cleaning of peak III and the glow curve deconvolution methods confirmed that the main peak is actually overlapped by a small peak (labeled peak IIA). The kinetic analysis of peak IIA showed that it is of first order kinetics and that its activation energy is 1:0 eV. In addition, the peak IIA is affected by thermal quenching. Another secondary peak appears at 422ºC (peak IV). However, the kinetic analysis of TL from peak IV was not studied because its intensity is not well defined. A heating rate of 0.4ºCs⁻¹ was used after a dose of 3 Gy in kinetic analysis of peaks IIA and III. The study of the PTTL showed that peaks I and II were regenerated under PTTL but peak III was not. Various effects of the PTTL for peaks I and II for different preheating temperatures in different samples were observed. The effect of annealing at 900ºC for 15 minutes between measurements following each illumination time was studied. The effect of dose on secondary peaks was also studied in this work. The kinetic analysis of the PTTL intensity for peak I showed that its activation energy is 0.7 eV, consistent with the activation energy of the normal TL for peak I. The PTTL intensity from peak I fades rapidly with storage compared with the thermal fading from peak I of the normal TL. The PTTL intensity for peak I decreases as a function of heating rate. This decrease was attributed to thermal quenching. Thermal quenching was not observed in the case of the normal TL intensity. The cause of this contrast requires further study.
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Masculinity, citizenship and political objection to compulsory military service in the South African Defence Force, 1978-1990
- Authors: Conway, Daniel John
- Date: 2013-08-15
- Subjects: Conscientious objectors -- South Africa End Conscription Campaign (South Africa) National service -- South Africa Draft -- South Africa South Africa -- Military policy Masculinity -- South Africa South Africa. South African Defense Force Gays in the military -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2601 , http://hdl.handle.net/10962/d1008383
- Description: This thesis conceptualises compulsory military service and objection to it as public performative acts that generate gendered and political identity. Conscription was the primary performance of citizenship and masculinity for white men in apartheid South Africa. Conscription was also a key governance strategy both in terms of upholding the authority of the state and in engendering discipline in the white population. Objection to military service was therefore a destabilising and transgressive public act. Competing conceptualisations of masculinity and citizenship are inherent in pro and anti-conscription discourses. The refusal to undertake military service places men outside the accepted means of graduating to ' real' manhood and patriotic citizenship. Although objection can be an iconic and transgressive act, objectors have an essentially ambivalent subjectivity in the public realm. Objectors are 'strangers' in a socially constructed and gendered binary of 'insiders' and 'outsiders' . This ambivalent status creates opportunities but also constraints for the performance of objection. The thesis analyses the effectiveness of objectors' performances and argues that there is a distinction between a radical challenge to hegemonic conceptions of militarised masculinity and citizenship and assimilatory challenges. The tension between radicalism and assimilation comes to the fore in response to the state's attacks on objectors. The militarised apartheid state is defined as not only masculine but heteronormative terms and it is the deployment of sexuality that is its most effective means of stigmatising and restricting the performance of objection. The thesis uses interview material, archival data and case studies and concludes that objectors (and their supporters) weaved multiple narratives into their performances but that as the 1980s progressed, the performance of objection to conscription became assimilatory and this demonstrates the heteronormativity of the state, military service and the public realm. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Conway, Daniel John
- Date: 2013-08-15
- Subjects: Conscientious objectors -- South Africa End Conscription Campaign (South Africa) National service -- South Africa Draft -- South Africa South Africa -- Military policy Masculinity -- South Africa South Africa. South African Defense Force Gays in the military -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2601 , http://hdl.handle.net/10962/d1008383
- Description: This thesis conceptualises compulsory military service and objection to it as public performative acts that generate gendered and political identity. Conscription was the primary performance of citizenship and masculinity for white men in apartheid South Africa. Conscription was also a key governance strategy both in terms of upholding the authority of the state and in engendering discipline in the white population. Objection to military service was therefore a destabilising and transgressive public act. Competing conceptualisations of masculinity and citizenship are inherent in pro and anti-conscription discourses. The refusal to undertake military service places men outside the accepted means of graduating to ' real' manhood and patriotic citizenship. Although objection can be an iconic and transgressive act, objectors have an essentially ambivalent subjectivity in the public realm. Objectors are 'strangers' in a socially constructed and gendered binary of 'insiders' and 'outsiders' . This ambivalent status creates opportunities but also constraints for the performance of objection. The thesis analyses the effectiveness of objectors' performances and argues that there is a distinction between a radical challenge to hegemonic conceptions of militarised masculinity and citizenship and assimilatory challenges. The tension between radicalism and assimilation comes to the fore in response to the state's attacks on objectors. The militarised apartheid state is defined as not only masculine but heteronormative terms and it is the deployment of sexuality that is its most effective means of stigmatising and restricting the performance of objection. The thesis uses interview material, archival data and case studies and concludes that objectors (and their supporters) weaved multiple narratives into their performances but that as the 1980s progressed, the performance of objection to conscription became assimilatory and this demonstrates the heteronormativity of the state, military service and the public realm. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Versions of virginity : an exploration of university students' narrative accounts of first sexual experience
- Authors: Ebden, Tiffany
- Date: 2013-05-21
- Subjects: College students -- South Africa -- Sexual behavior Sexual intercourse -- Psychological aspects Virginity
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3170 , http://hdl.handle.net/10962/d1007797
- Description: The research assumes a narrative constructionist and feminist perspective in order to explore stories concerning men and women's first sexual experience. Such a metatheoretical stance is concerned with the ways that lives are constructed and storied through language. There is a concern for the myriad voices, both personal and social, that speaks through individuals' stories and for the manner in which these voices are represented. Three men and three women were interviewed to elicit narratives of first sexual experience. The analysis of interview transcripts tells first sexual experience as a rite of passage described in terms of certain mythic elements. That is, the experience of first sex concerns three stages. Firstly the individual is detached from the experience of sex while still a virgin. Secondly the experience itself is one that is ineffable and diffuse. Thirdly the individual must make sense of the experience. Participants' experience could be characterised as containing elements of demonic, heavenly or earthly myths about sexual relationships: demonic elements concerned the base , physical and painful experiences of first sex; the myth of heavenly love emphasises the mental and emotional connection between partners; an earthly myth tells sex as a predestined meeting of two partners. The manner in which stories were constructed was different for male and for female participants, and these differences have implications for the power dynamics at play between genders in the context of sexual interaction, especially first sex. Further the research's storied and ritualised approach to these gender differences suggests the performative aspect of gender. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Ebden, Tiffany
- Date: 2013-05-21
- Subjects: College students -- South Africa -- Sexual behavior Sexual intercourse -- Psychological aspects Virginity
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3170 , http://hdl.handle.net/10962/d1007797
- Description: The research assumes a narrative constructionist and feminist perspective in order to explore stories concerning men and women's first sexual experience. Such a metatheoretical stance is concerned with the ways that lives are constructed and storied through language. There is a concern for the myriad voices, both personal and social, that speaks through individuals' stories and for the manner in which these voices are represented. Three men and three women were interviewed to elicit narratives of first sexual experience. The analysis of interview transcripts tells first sexual experience as a rite of passage described in terms of certain mythic elements. That is, the experience of first sex concerns three stages. Firstly the individual is detached from the experience of sex while still a virgin. Secondly the experience itself is one that is ineffable and diffuse. Thirdly the individual must make sense of the experience. Participants' experience could be characterised as containing elements of demonic, heavenly or earthly myths about sexual relationships: demonic elements concerned the base , physical and painful experiences of first sex; the myth of heavenly love emphasises the mental and emotional connection between partners; an earthly myth tells sex as a predestined meeting of two partners. The manner in which stories were constructed was different for male and for female participants, and these differences have implications for the power dynamics at play between genders in the context of sexual interaction, especially first sex. Further the research's storied and ritualised approach to these gender differences suggests the performative aspect of gender. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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An exploration of strategies to enhance grade 8 learners' reading comprehension skills
- Authors: Matakane, Euphimia Nobuzwe
- Date: 2013
- Subjects: Reading (Secondary) -- Research Reading comprehension
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1834 , http://hdl.handle.net/10962/d1004330
- Description: This thesis reports on an Action Research case study into the teaching of comprehension strategies to Grade 8 learners in a rural high school in the Eastern Cape, South Africa. The learners in this study, who were studying English as an additional language, experienced difficulties in comprehending English text. A series of six lessons were designed to teach comprehension strategies to improve the learners' performance in reading comprehension. The purpose of the intervention was to equip the learners with skills that would enable them to improve their reading comprehension and evaluate their effectiveness as readers. The intervention was also intended to assess my teaching, which was challenged by the need to deal with learners' poor levels of reading comprehension. The data was collected using the following research techniques: interviews, questionnaires, non-participant observation, learners' and researcher's journals, document analysis The data analysis revealed that a lack of resources to learn English; limited English language due to lack of exposure; and learners' lack of foundational knowledge from their primary schools were barriers to the successful teaching of comprehension strategies. Despite such barriers, however, this research provides evidence that teaching comprehension strategies can be effective if it is taught systematically, and applied continuously. Personally, I learnt that I had to modify my methods of teaching due to the response of learners to the lessons taught.
- Full Text:
- Authors: Matakane, Euphimia Nobuzwe
- Date: 2013
- Subjects: Reading (Secondary) -- Research Reading comprehension
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1834 , http://hdl.handle.net/10962/d1004330
- Description: This thesis reports on an Action Research case study into the teaching of comprehension strategies to Grade 8 learners in a rural high school in the Eastern Cape, South Africa. The learners in this study, who were studying English as an additional language, experienced difficulties in comprehending English text. A series of six lessons were designed to teach comprehension strategies to improve the learners' performance in reading comprehension. The purpose of the intervention was to equip the learners with skills that would enable them to improve their reading comprehension and evaluate their effectiveness as readers. The intervention was also intended to assess my teaching, which was challenged by the need to deal with learners' poor levels of reading comprehension. The data was collected using the following research techniques: interviews, questionnaires, non-participant observation, learners' and researcher's journals, document analysis The data analysis revealed that a lack of resources to learn English; limited English language due to lack of exposure; and learners' lack of foundational knowledge from their primary schools were barriers to the successful teaching of comprehension strategies. Despite such barriers, however, this research provides evidence that teaching comprehension strategies can be effective if it is taught systematically, and applied continuously. Personally, I learnt that I had to modify my methods of teaching due to the response of learners to the lessons taught.
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An investigation of the discursive construction of the Tanganyika-Zanzibar Union as nation in the Union Day coverage in The Citizen and Daily News newspapers from 2005 to 2011
- Authors: Dotto, Paul Casmir Kuhenga
- Date: 2013
- Subjects: Newspapers -- Research -- Tanzania , Press and politics -- Tanzania , Tanzania -- Politics and government -- 1964- , Zanzibar -- Politics and government -- 1964- , Press , Daily News , The Citizen , Union Day , Nation building
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3412 , http://hdl.handle.net/10962/d1001843
- Description: This study is concerned with the constructions of the Tanzanian nation in the press. It has confined its focus, first, to the coverage from 2005 to 2011 on Union Day that marks the Union between Tanganyika and Zanzibar and the formation of the United Republic of Tanzania and, second, to two prominent Tanzanian newspapers, namely the state-owned Daily News, and the privately-owned The Citizen on Union Day. As the Union remains a contentious issue, the relevance of this research relates to the press’s considerable power to shape understandings and influence attitudes. The study works within a broad cultural and media studies framework and is informed by a constructionist approach to representation and to culture, and to nation in particular. It also draws of journalistic theories of agenda-setting and the normative roles of the press to probe the agendas set by the press on Union Day and to interrogate how the two newspapers construct and frame the Union of Tanganyika and Zanzibar as nation. The research responds to the question: ‘How has the Tanganyika-Zanzibar Union been represented in The Citizen and Daily News newspapers from 2005 to 2011?’ It employs quantitative and qualitative (thematic) content analysis to investigate the coverage in the editorials and feature articles of The Citizen and Daily News newspapers on Union Day (26 April) of 2005 to 2011. This study finds that the government-owned newspaper, Daily News, publishes more articles related to Union on Union Day than the privately-owned, The Citizen and collaborates more determinedly with the state in the process of constructing the nation. However, both newspapers adopt a collaborative role consistent with the development journalism tradition that endorses an informal partnership between media and the state in the process of development (Christians et al, 2009:201). Both publications tend to emphasise the hegemonic ideology pertaining to Union while giving limited attention to challenges to such constructions. While both newspapers do identify certain problems of the Union and thus exercise a monitorial role to varying extents, it is apparent that the press in Tanzania tends to be largely acritical, perhaps attributable to a long period under single party rule
- Full Text:
- Authors: Dotto, Paul Casmir Kuhenga
- Date: 2013
- Subjects: Newspapers -- Research -- Tanzania , Press and politics -- Tanzania , Tanzania -- Politics and government -- 1964- , Zanzibar -- Politics and government -- 1964- , Press , Daily News , The Citizen , Union Day , Nation building
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3412 , http://hdl.handle.net/10962/d1001843
- Description: This study is concerned with the constructions of the Tanzanian nation in the press. It has confined its focus, first, to the coverage from 2005 to 2011 on Union Day that marks the Union between Tanganyika and Zanzibar and the formation of the United Republic of Tanzania and, second, to two prominent Tanzanian newspapers, namely the state-owned Daily News, and the privately-owned The Citizen on Union Day. As the Union remains a contentious issue, the relevance of this research relates to the press’s considerable power to shape understandings and influence attitudes. The study works within a broad cultural and media studies framework and is informed by a constructionist approach to representation and to culture, and to nation in particular. It also draws of journalistic theories of agenda-setting and the normative roles of the press to probe the agendas set by the press on Union Day and to interrogate how the two newspapers construct and frame the Union of Tanganyika and Zanzibar as nation. The research responds to the question: ‘How has the Tanganyika-Zanzibar Union been represented in The Citizen and Daily News newspapers from 2005 to 2011?’ It employs quantitative and qualitative (thematic) content analysis to investigate the coverage in the editorials and feature articles of The Citizen and Daily News newspapers on Union Day (26 April) of 2005 to 2011. This study finds that the government-owned newspaper, Daily News, publishes more articles related to Union on Union Day than the privately-owned, The Citizen and collaborates more determinedly with the state in the process of constructing the nation. However, both newspapers adopt a collaborative role consistent with the development journalism tradition that endorses an informal partnership between media and the state in the process of development (Christians et al, 2009:201). Both publications tend to emphasise the hegemonic ideology pertaining to Union while giving limited attention to challenges to such constructions. While both newspapers do identify certain problems of the Union and thus exercise a monitorial role to varying extents, it is apparent that the press in Tanzania tends to be largely acritical, perhaps attributable to a long period under single party rule
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What future graduates will value in their leaders: a study across gender and culture
- Authors: Cox, Andrea
- Date: 2013
- Subjects: Leadership -- South Africa Leadership -- Evaluation -- South Africa Culture -- South Africa Social values -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1195 , http://hdl.handle.net/10962/d1008197
- Description: Effective leadership has been found to be a key determinant of organisational success. Effective leadership does not only involve the ability to influence and inspire others, it is the ability to lead subordinates according to the competencies that they value. The focus of this study is on determining what in fact the future South African graduate workforce will value in a leader. Effective leadership and the competencies that subordinate's value is especially relevant today as leadership is forced to contend with an increasingly diverse workforce. This diversity necessitates the need for a leadership style to be congruent with what subordinates of diverse genders and cultures will value, so to be effective. Existing studies have indicated that gender and culture influence what subordinate's value in a leader, however it is evident from the results of this study, that this is not entirely the case. Regarding gender, the female and male respondents in this study value similar competencies in their leader, indicating that there is no distinct set of competencies that will be valued by male and female graduates. With respect to culture, the respondents value a mixture of competencies that combine both African and Western leadership practices, values and philosophies, indicating that there is no distinct set of competencies that will be valued by African, Coloured, Indian and White graduates. On the basis of this research, the recommendation is that for leaders to be effective in the 21 st century, a leader must be loyal and inspirational, have vision and integrity and lastly must be open and honest with their subordinates
- Full Text:
- Authors: Cox, Andrea
- Date: 2013
- Subjects: Leadership -- South Africa Leadership -- Evaluation -- South Africa Culture -- South Africa Social values -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1195 , http://hdl.handle.net/10962/d1008197
- Description: Effective leadership has been found to be a key determinant of organisational success. Effective leadership does not only involve the ability to influence and inspire others, it is the ability to lead subordinates according to the competencies that they value. The focus of this study is on determining what in fact the future South African graduate workforce will value in a leader. Effective leadership and the competencies that subordinate's value is especially relevant today as leadership is forced to contend with an increasingly diverse workforce. This diversity necessitates the need for a leadership style to be congruent with what subordinates of diverse genders and cultures will value, so to be effective. Existing studies have indicated that gender and culture influence what subordinate's value in a leader, however it is evident from the results of this study, that this is not entirely the case. Regarding gender, the female and male respondents in this study value similar competencies in their leader, indicating that there is no distinct set of competencies that will be valued by male and female graduates. With respect to culture, the respondents value a mixture of competencies that combine both African and Western leadership practices, values and philosophies, indicating that there is no distinct set of competencies that will be valued by African, Coloured, Indian and White graduates. On the basis of this research, the recommendation is that for leaders to be effective in the 21 st century, a leader must be loyal and inspirational, have vision and integrity and lastly must be open and honest with their subordinates
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A South African perspective on the tax implications of virtual asset accumulation and transactions stemming from persistent virtual worlds
- Authors: Haupt, Alexander
- Date: 2012
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:884 , http://hdl.handle.net/10962/d1001638
- Description: Massively multiplayer online role-playing games are growing in popularity with millions of people participating in these persistent online environments on a daily basis. Accompanying the ever-increasing subscription numbers is an increase in real money trade transactions stemming from these game worlds. The research question to be addressed in this thesis is whether transactions stemming from virtual worlds have real-world taxation consequences. The goal of this research is to determine the taxability of virtual assets obtained in structured as well as unstructured virtual environments and to attempt to establish the differences between capital and revenue receipts in these virtual realms, taking into account the nature of a receipt. The general deduction formula is applied to establish the deductibility of expenditure incurred whilst participating in these virtual environments. Sundry matters such as Value-Added Tax, donations tax, the withholding tax on gambling gains and tax avoidance will also be addressed. The methodology adopted for the research could best be described as interpretative, aimed at analysing and interpreting the relationship between real world taxes and persistent virtual worlds and the transactions that stem from participation therein. The research is based purely on documentary evidence. After applying relevant tax legislation to virtual economies it became evident that merely because virtual assets only exist in virtual reality does not necessarily preclude them real world tax consequences. It was concluded, however, that it is not practical for the South African Revenue Service to monitor all virtual world transactions or for participant taxpayers to calculate the real world value of each and every asset acquired in-world. As a result, it was concluded that real world tax consequences should only be applied in situations where participants actually convert their virtual assets into real world currency.
- Full Text:
- Authors: Haupt, Alexander
- Date: 2012
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:884 , http://hdl.handle.net/10962/d1001638
- Description: Massively multiplayer online role-playing games are growing in popularity with millions of people participating in these persistent online environments on a daily basis. Accompanying the ever-increasing subscription numbers is an increase in real money trade transactions stemming from these game worlds. The research question to be addressed in this thesis is whether transactions stemming from virtual worlds have real-world taxation consequences. The goal of this research is to determine the taxability of virtual assets obtained in structured as well as unstructured virtual environments and to attempt to establish the differences between capital and revenue receipts in these virtual realms, taking into account the nature of a receipt. The general deduction formula is applied to establish the deductibility of expenditure incurred whilst participating in these virtual environments. Sundry matters such as Value-Added Tax, donations tax, the withholding tax on gambling gains and tax avoidance will also be addressed. The methodology adopted for the research could best be described as interpretative, aimed at analysing and interpreting the relationship between real world taxes and persistent virtual worlds and the transactions that stem from participation therein. The research is based purely on documentary evidence. After applying relevant tax legislation to virtual economies it became evident that merely because virtual assets only exist in virtual reality does not necessarily preclude them real world tax consequences. It was concluded, however, that it is not practical for the South African Revenue Service to monitor all virtual world transactions or for participant taxpayers to calculate the real world value of each and every asset acquired in-world. As a result, it was concluded that real world tax consequences should only be applied in situations where participants actually convert their virtual assets into real world currency.
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Post-apartheid racial integration in Grahamstown : a time-geographical perspective
- Authors: Irvine, Philippa Margaret
- Date: 2012
- Subjects: Race discrimination -- South Africa -- Eastern Cape Grahamstown (South Africa) -- Race relations Grahamstown (South Africa) -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:4845 , http://hdl.handle.net/10962/d1005521
- Description: This research is situated within the context of the post-apartheid era in South Africa, which includes the dominant ideologies and policies that have shaped the urban landscape of the past and present. It investigates the extent and patterns of integration that exist twenty years after the country’s political transition and it uses Grahamstown, a small education and cultural centre in the Eastern Cape Province, as its case study. The investigation incorporates the traditional geographical focus of residential and educational integration, using conventional means of investigation such as segregation indices, dissimilarity indices, percentages and maps. However, in identifying the broader nature of ‘segregation’ and ‘integration’, the study moves beyond these foci and approaches. It adopts the timegeographical framework to reveal the dynamic use of urban space that reflects the lived space of selected individuals from the community of Grahamstown: the extent and patterns of their behavioural integration or spatial linkages. Together, these approaches reveal that Grahamstown is still a city divided by race and, now, class. Schools and residential areas remain tied to the apartheid divisions of race and the white community exists almost entirely within the bounds of apartheid’s blueprint of urban space. Rhodes University, which is located within Grahamstown, has experienced admirable levels of integration within the student body and within the staff as a whole, but not within the staff’s different levels. In essence, where integration has occurred it has been unidirectional with the black community moving into the spaces and institutions formerly reserved for whites. The limited behavioural integration or spatial linkages are shown to be tied to city structure and, within the white group, to perceptions of ‘otherness’ held by the individuals interviewed. While the study shows limited differences in the time-spatial movements between members of different races who are resident in the former white group area, it highlights the differences between those more permanently resident in the city and the temporary educational migrants or students. The study argues that the slow pace of change is related to the nature of South Africa’s democratic transition and its attending political and economic policies.
- Full Text:
- Authors: Irvine, Philippa Margaret
- Date: 2012
- Subjects: Race discrimination -- South Africa -- Eastern Cape Grahamstown (South Africa) -- Race relations Grahamstown (South Africa) -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:4845 , http://hdl.handle.net/10962/d1005521
- Description: This research is situated within the context of the post-apartheid era in South Africa, which includes the dominant ideologies and policies that have shaped the urban landscape of the past and present. It investigates the extent and patterns of integration that exist twenty years after the country’s political transition and it uses Grahamstown, a small education and cultural centre in the Eastern Cape Province, as its case study. The investigation incorporates the traditional geographical focus of residential and educational integration, using conventional means of investigation such as segregation indices, dissimilarity indices, percentages and maps. However, in identifying the broader nature of ‘segregation’ and ‘integration’, the study moves beyond these foci and approaches. It adopts the timegeographical framework to reveal the dynamic use of urban space that reflects the lived space of selected individuals from the community of Grahamstown: the extent and patterns of their behavioural integration or spatial linkages. Together, these approaches reveal that Grahamstown is still a city divided by race and, now, class. Schools and residential areas remain tied to the apartheid divisions of race and the white community exists almost entirely within the bounds of apartheid’s blueprint of urban space. Rhodes University, which is located within Grahamstown, has experienced admirable levels of integration within the student body and within the staff as a whole, but not within the staff’s different levels. In essence, where integration has occurred it has been unidirectional with the black community moving into the spaces and institutions formerly reserved for whites. The limited behavioural integration or spatial linkages are shown to be tied to city structure and, within the white group, to perceptions of ‘otherness’ held by the individuals interviewed. While the study shows limited differences in the time-spatial movements between members of different races who are resident in the former white group area, it highlights the differences between those more permanently resident in the city and the temporary educational migrants or students. The study argues that the slow pace of change is related to the nature of South Africa’s democratic transition and its attending political and economic policies.
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An evaluation of the feasibility of obtaining payment for ecosystem services for the Baviaanskloof Nature Reserve
- Authors: Erlank, Wayne Michael
- Date: 2011
- Subjects: Ecosystem services -- South Africa -- Eastern Cape Ecology -- Economic aspects -- South Africa -- Eastern Cape Environmental economics -- South Africa -- Eastern Cape Water-supply -- South Africa -- Eastern Cape Water-supply -- South Africa -- Eastern Cape -- Management Water resources development -- South Africa -- Eastern Cape Nature conservation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:742 , http://hdl.handle.net/10962/d1003862
- Description: Cities must go further and further away to find new, more costly sources of water for human consumption while industries and agriculture continue to compete for increasingly scarce water resources. This may already be seen occurring within the Nelson Mandela Bay Metro where the severe drought being experienced during the past 18 months has severely depleted water supply dams. One of the main supply dams to the Nelson Mandela Bay Municipality is situated within the Baviaanskloof Nature Reserve and World Heritage Site. The potential of funding the Baviaanskloof Nature Reserve and World Heritage Site with payments for ecosystem services (water) obtained for water services supplied to the Nelson Mandela Bay Municipalities and agriculture in the Gamtoos River Valley will ensure financial sustainable for the Baviaanskloof Nature Reserve and World Heritage Site in the long term. This ability to become financially independent and generate its own income will place the Baviaanskloof Nature Reserve and World Heritage Site in a unique position within the conservation community in South Africa as only a very few protected areas are self sustaining through payment for an ecosystem service.
- Full Text:
- Authors: Erlank, Wayne Michael
- Date: 2011
- Subjects: Ecosystem services -- South Africa -- Eastern Cape Ecology -- Economic aspects -- South Africa -- Eastern Cape Environmental economics -- South Africa -- Eastern Cape Water-supply -- South Africa -- Eastern Cape Water-supply -- South Africa -- Eastern Cape -- Management Water resources development -- South Africa -- Eastern Cape Nature conservation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:742 , http://hdl.handle.net/10962/d1003862
- Description: Cities must go further and further away to find new, more costly sources of water for human consumption while industries and agriculture continue to compete for increasingly scarce water resources. This may already be seen occurring within the Nelson Mandela Bay Metro where the severe drought being experienced during the past 18 months has severely depleted water supply dams. One of the main supply dams to the Nelson Mandela Bay Municipality is situated within the Baviaanskloof Nature Reserve and World Heritage Site. The potential of funding the Baviaanskloof Nature Reserve and World Heritage Site with payments for ecosystem services (water) obtained for water services supplied to the Nelson Mandela Bay Municipalities and agriculture in the Gamtoos River Valley will ensure financial sustainable for the Baviaanskloof Nature Reserve and World Heritage Site in the long term. This ability to become financially independent and generate its own income will place the Baviaanskloof Nature Reserve and World Heritage Site in a unique position within the conservation community in South Africa as only a very few protected areas are self sustaining through payment for an ecosystem service.
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The application of a landscape diversity index using remote sensing and geographical information systems to identify degradation patterns in the Great Fish River Valley, Eastern Cape Province, South Africa
- Authors: Tanser, Frank Courteney
- Date: 1997
- Subjects: Geographic information systems , Earth sciences -- Remote sensing , Environmental degradation -- South Africa -- Eastern Cape -- Great Fish River Valley , Forest degradation -- South Africa -- Eastern Cape -- Great Rish River Valley
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4814 , http://hdl.handle.net/10962/d1005488 , Geographic information systems , Earth sciences -- Remote sensing , Environmental degradation -- South Africa -- Eastern Cape -- Great Fish River Valley , Forest degradation -- South Africa -- Eastern Cape -- Great Rish River Valley
- Description: Using a range of satellite-derived indices I describe. monitor and predict vegetation conditions that exist in the Great Fish River Valley, Eastern Cape. The heterogeneous nature of the area necessitates that the mapping of vegetation classes be accomplished using a combination of a supervised approach, an unsupervised approach and the use of a Moving Standard Deviation Index (MSDI). Nine vegetation classes are identified and mapped at an accuracy of 84%. The vegetation classes are strongly related to land-use and the communal areas demonstrate a reduction in palatable species and a shift towards dominance by a single species. Nature reserves and commercial rangeland are by contrast dominated by good condition vegetation types. The Modified Soil Adjusted Vegetation Index (MSA VI) is used to map the vegetation production in the study area. The influence of soil reflectance is reduced using this index. The MSA VI proves to be a good predictor of vegetation condition in the higher rainfall areas but not in the more semi-arid regions. The MSA VI has a significant relationship to rainfall but no absolute relationship to biomass. However, a stratification approach (on the basis of vegetation type) reveals that the MSA VI exhibits relationships to biomass in vegetation types occurring in the higher rainfall areas and consisting of a large cover of shrubs. A technique based on an index which describes landscape spatial variability is presented to assist in the interpretation of landscape condition. The research outlines a method for degradation assessment which overcomes many of the problems associated with cost and repeatability. Indices that attempt to provide a correlation with net primary productivity, e.g. NDVI, do not consider changes in the quality of net primary productivity. Landscape variability represents a measure of ecosystem change in the landscape that underlies the degradation process. The hypothesis is that healthy/undisturbed/stable landscapes tend to be less variable and homogenous than their degraded heterogenous counterparts. The Moving Standard Deviation Index (MSDI) is calculated by performing a 3 x 3 moving standard deviation window across Landsat Thematic Mapper (TM) band 3. The result is a sensitive indicator of landscape condition which is not affected by moisture availability and vegetation type. The MSDI shows a significant negative relationship to NDVI confirming its relationship to condition. The cross-classification of MSDI with NDVI allows the identification of invasive woody weeds which exhibit strong photosynthetic signals and would therefore be categorised as good condition using NDVI. Other ecosystems are investigated to determine the relationship between NDVI and MSDI. Where increase in NDVI is disturbance-induced (such as the Kalahari Desert) the relationship is positive. Where high NDVI values are indicative of good condition rangeland (such as the Fish River Valley) the relationship is negative. The MSDI therefore always exhibits a significant positive relationship to degradation irrespective of the relationship of NDVI to condition in the ecosystem.
- Full Text:
- Authors: Tanser, Frank Courteney
- Date: 1997
- Subjects: Geographic information systems , Earth sciences -- Remote sensing , Environmental degradation -- South Africa -- Eastern Cape -- Great Fish River Valley , Forest degradation -- South Africa -- Eastern Cape -- Great Rish River Valley
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4814 , http://hdl.handle.net/10962/d1005488 , Geographic information systems , Earth sciences -- Remote sensing , Environmental degradation -- South Africa -- Eastern Cape -- Great Fish River Valley , Forest degradation -- South Africa -- Eastern Cape -- Great Rish River Valley
- Description: Using a range of satellite-derived indices I describe. monitor and predict vegetation conditions that exist in the Great Fish River Valley, Eastern Cape. The heterogeneous nature of the area necessitates that the mapping of vegetation classes be accomplished using a combination of a supervised approach, an unsupervised approach and the use of a Moving Standard Deviation Index (MSDI). Nine vegetation classes are identified and mapped at an accuracy of 84%. The vegetation classes are strongly related to land-use and the communal areas demonstrate a reduction in palatable species and a shift towards dominance by a single species. Nature reserves and commercial rangeland are by contrast dominated by good condition vegetation types. The Modified Soil Adjusted Vegetation Index (MSA VI) is used to map the vegetation production in the study area. The influence of soil reflectance is reduced using this index. The MSA VI proves to be a good predictor of vegetation condition in the higher rainfall areas but not in the more semi-arid regions. The MSA VI has a significant relationship to rainfall but no absolute relationship to biomass. However, a stratification approach (on the basis of vegetation type) reveals that the MSA VI exhibits relationships to biomass in vegetation types occurring in the higher rainfall areas and consisting of a large cover of shrubs. A technique based on an index which describes landscape spatial variability is presented to assist in the interpretation of landscape condition. The research outlines a method for degradation assessment which overcomes many of the problems associated with cost and repeatability. Indices that attempt to provide a correlation with net primary productivity, e.g. NDVI, do not consider changes in the quality of net primary productivity. Landscape variability represents a measure of ecosystem change in the landscape that underlies the degradation process. The hypothesis is that healthy/undisturbed/stable landscapes tend to be less variable and homogenous than their degraded heterogenous counterparts. The Moving Standard Deviation Index (MSDI) is calculated by performing a 3 x 3 moving standard deviation window across Landsat Thematic Mapper (TM) band 3. The result is a sensitive indicator of landscape condition which is not affected by moisture availability and vegetation type. The MSDI shows a significant negative relationship to NDVI confirming its relationship to condition. The cross-classification of MSDI with NDVI allows the identification of invasive woody weeds which exhibit strong photosynthetic signals and would therefore be categorised as good condition using NDVI. Other ecosystems are investigated to determine the relationship between NDVI and MSDI. Where increase in NDVI is disturbance-induced (such as the Kalahari Desert) the relationship is positive. Where high NDVI values are indicative of good condition rangeland (such as the Fish River Valley) the relationship is negative. The MSDI therefore always exhibits a significant positive relationship to degradation irrespective of the relationship of NDVI to condition in the ecosystem.
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A combination of a stationary and non-stationary model to predict corporate failure in South Africa
- Authors: Court, Philip Wathen
- Date: 1994
- Subjects: Bankruptcy -- South Africa Business planning -- South Africa Business failures -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1183 , http://hdl.handle.net/10962/d1002800
- Description: Business failure should be of concern in most industralised countries and the importance of accurately evaluating the phenomenon from a management and investment point of view is enormous. Were it possible to predict failure with a certain degree of confidence, steps could be taken to rectify the situation and the benefit would accrue to all of the stakeholders in the macroenvironment. In essence, the profitability of a business is influenced by two sets of variables. In the first instance, it is influenced by a variety of internal (microeconomic) variables which are firm- specific and which management is generally able to control. A further distinction in this regard may be made between the financial and non-financial variables. In the second instance, it is generally accepted that profitability will be influenced by a number of external (macroeconomic) variables which are generally beyond the control of management. In the main, however, the profitability of the firm is generally determined by a combination of both sets of factors. To date, a great deal of research has been undertaken in an attempt to establish a reliable model which may be used to predict failure. This has mainly been confined to the microeconomic variables which can be used to predict failure and attempts have been made to isolate either a single financial ratio or a number of financial and non-financial variables which can be used to model corporate failure. The research has met with a certain degree of success although this appears to be confined to the economic environment to which the models have been applied. The models are less successful when applied to other macroenvironments. Limited research has been undertaken into the macroeconomic variables which contribute to business failure or to a combination of the two types of variables. It is appropriate therefore that further consideration be given to the establishment of a model incorporating ALL the variables which could contribute to corporate failure. The purpose of this research is to undertake an investigation of micro- and macroeconomic variables that are freely available to reserachers and which may be used in a failure prediction model. The intention is to obtain a comprehensive, yet simple model which can be used as an overall predictor of PENDING failure.
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- Authors: Court, Philip Wathen
- Date: 1994
- Subjects: Bankruptcy -- South Africa Business planning -- South Africa Business failures -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1183 , http://hdl.handle.net/10962/d1002800
- Description: Business failure should be of concern in most industralised countries and the importance of accurately evaluating the phenomenon from a management and investment point of view is enormous. Were it possible to predict failure with a certain degree of confidence, steps could be taken to rectify the situation and the benefit would accrue to all of the stakeholders in the macroenvironment. In essence, the profitability of a business is influenced by two sets of variables. In the first instance, it is influenced by a variety of internal (microeconomic) variables which are firm- specific and which management is generally able to control. A further distinction in this regard may be made between the financial and non-financial variables. In the second instance, it is generally accepted that profitability will be influenced by a number of external (macroeconomic) variables which are generally beyond the control of management. In the main, however, the profitability of the firm is generally determined by a combination of both sets of factors. To date, a great deal of research has been undertaken in an attempt to establish a reliable model which may be used to predict failure. This has mainly been confined to the microeconomic variables which can be used to predict failure and attempts have been made to isolate either a single financial ratio or a number of financial and non-financial variables which can be used to model corporate failure. The research has met with a certain degree of success although this appears to be confined to the economic environment to which the models have been applied. The models are less successful when applied to other macroenvironments. Limited research has been undertaken into the macroeconomic variables which contribute to business failure or to a combination of the two types of variables. It is appropriate therefore that further consideration be given to the establishment of a model incorporating ALL the variables which could contribute to corporate failure. The purpose of this research is to undertake an investigation of micro- and macroeconomic variables that are freely available to reserachers and which may be used in a failure prediction model. The intention is to obtain a comprehensive, yet simple model which can be used as an overall predictor of PENDING failure.
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Author, ideology and publisher a symbiotic relationship : Lovedale Missionary Press and early Black writing in South Africa: with specific reference to the critical writings of H.I.E. Dlomo
- Authors: Midgley, Henry Peter
- Date: 1994
- Subjects: Shepherd, Robert H W (Robert Henry Wishart), 1888-1971 Dhlomo, H I E (Herbert I E), 1903-1956 Rhodes University Dissertations African literature Lovedale Institution South African literature -- Black authors -- History and criticism South African literature (English) -- History and criticism Politics and literature -- South Africa -- History -- 20th century Press and politics -- South Africa -- History
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2241 , http://hdl.handle.net/10962/d1002284
- Description: The specific instances of R.H.W. Shepherd and H.I.E. Dhlomo are used in this thesis to investigate some of the many factors that influence the formation of a colonial literature, such as politics, social structures and personal ideals. By isolating the Lovedale Mission Press ~s a "contact zone" - a·place where the cultures of the colonizer and the colonized come into direct contact with each other - it is possible to trace how the interaction between these cultures shaped the writing of a particular African writer, H.I.E. Dhlomo. This is done through an analysis of historical factors that shaped the policy of the Lovedale Mission Press in the twentieth century: the development of liberalism in South Africa, the·role of the missionary in African education, the function ofa liberal magazine such as The South African Outlook and the appointment of an ambitious missionary, R.I.W. Shepherd, to the position of Director of Publications. This necessarily included a study of Shepherd's vision of African literature. On the other hand, this study takes cognisance of the factors that shaped Herbert Dhlomo's vision of literature: the development of African nationalism, the entrenchment of segregation as a politial doctrine, and most importantly, his struggle to have his creative writing published by the Lovedale Press. It is shown how Shepherd's vision of what African literature should entail contrasted with Dhlomo's, and how, as a result, Dhlomo deliberately structured his critical writing as a response to Shepherd's Eurocentric approach to African literature.
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- Authors: Midgley, Henry Peter
- Date: 1994
- Subjects: Shepherd, Robert H W (Robert Henry Wishart), 1888-1971 Dhlomo, H I E (Herbert I E), 1903-1956 Rhodes University Dissertations African literature Lovedale Institution South African literature -- Black authors -- History and criticism South African literature (English) -- History and criticism Politics and literature -- South Africa -- History -- 20th century Press and politics -- South Africa -- History
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2241 , http://hdl.handle.net/10962/d1002284
- Description: The specific instances of R.H.W. Shepherd and H.I.E. Dhlomo are used in this thesis to investigate some of the many factors that influence the formation of a colonial literature, such as politics, social structures and personal ideals. By isolating the Lovedale Mission Press ~s a "contact zone" - a·place where the cultures of the colonizer and the colonized come into direct contact with each other - it is possible to trace how the interaction between these cultures shaped the writing of a particular African writer, H.I.E. Dhlomo. This is done through an analysis of historical factors that shaped the policy of the Lovedale Mission Press in the twentieth century: the development of liberalism in South Africa, the·role of the missionary in African education, the function ofa liberal magazine such as The South African Outlook and the appointment of an ambitious missionary, R.I.W. Shepherd, to the position of Director of Publications. This necessarily included a study of Shepherd's vision of African literature. On the other hand, this study takes cognisance of the factors that shaped Herbert Dhlomo's vision of literature: the development of African nationalism, the entrenchment of segregation as a politial doctrine, and most importantly, his struggle to have his creative writing published by the Lovedale Press. It is shown how Shepherd's vision of what African literature should entail contrasted with Dhlomo's, and how, as a result, Dhlomo deliberately structured his critical writing as a response to Shepherd's Eurocentric approach to African literature.
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Educational computing in secondary schools of the Cape Education Department: a research survey to assess computing facility acquisition and its utilization
- Authors: Bean, Pat
- Date: 1992
- Subjects: Education, Secondary -- South Africa -- Data processing Education, Secondary -- South Africa -- Computer network resources Computer-assisted instruction -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1505 , http://hdl.handle.net/10962/d1003387
- Description: Secondary schools under the jurisdiction of the Cape Education Department (CED) have, over the past 10 years, been acquiring computer equipment without a national policy on educational computing in South Africa, and within only broad parameters provided by their department. The aim of this study was to determine the present status of educational computing in these schools. A literature survey on educational computing was undertaken and a number of international and local 'computers-in-schools' initiatives were elucidated. A field survey, involving all CED secondary schools (239), was initiated by sending questionnaires to principals of these schools - a return rate of 89% was achieved. The results of the research revealed that most CED secondary schools have already acquired computer facilities. The role of pressure groups such as teachers, parents, business sector etc together with other factors that might have influenced schools in acquiring their computer facilities was also investigated. The investigation also revealed where and how these facilities are being utilised: most schools use their computers for administrative functions, with the computer-as-a-tool for teachers and pupils also fast gaining ground. Computer-assisted learning activities, where the computer is integrated with subject curricula, are however still limited. The extent of both teachers' formal training in educational computing and their familiarity with different software applications were also determined. Schools were also required to indicate the areas where they experience problems in getting teachers and pupils more involved in 'computers-in-education' activities. The present educational computing position in secondary schools of the CED will have to serve as a foundation for the department's CISR Project embarked upon in 1991.
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- Authors: Bean, Pat
- Date: 1992
- Subjects: Education, Secondary -- South Africa -- Data processing Education, Secondary -- South Africa -- Computer network resources Computer-assisted instruction -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1505 , http://hdl.handle.net/10962/d1003387
- Description: Secondary schools under the jurisdiction of the Cape Education Department (CED) have, over the past 10 years, been acquiring computer equipment without a national policy on educational computing in South Africa, and within only broad parameters provided by their department. The aim of this study was to determine the present status of educational computing in these schools. A literature survey on educational computing was undertaken and a number of international and local 'computers-in-schools' initiatives were elucidated. A field survey, involving all CED secondary schools (239), was initiated by sending questionnaires to principals of these schools - a return rate of 89% was achieved. The results of the research revealed that most CED secondary schools have already acquired computer facilities. The role of pressure groups such as teachers, parents, business sector etc together with other factors that might have influenced schools in acquiring their computer facilities was also investigated. The investigation also revealed where and how these facilities are being utilised: most schools use their computers for administrative functions, with the computer-as-a-tool for teachers and pupils also fast gaining ground. Computer-assisted learning activities, where the computer is integrated with subject curricula, are however still limited. The extent of both teachers' formal training in educational computing and their familiarity with different software applications were also determined. Schools were also required to indicate the areas where they experience problems in getting teachers and pupils more involved in 'computers-in-education' activities. The present educational computing position in secondary schools of the CED will have to serve as a foundation for the department's CISR Project embarked upon in 1991.
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An erosion hazard assessment technique for Ciskei
- Authors: Weaver, Alex van Breda
- Date: 1989
- Subjects: Soil erosion -- South Africa -- Ciskei
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4792 , http://hdl.handle.net/10962/d1001892
- Description: The study examines the relationship between the spatial variation in soil erosion and various natural and anthropogenic attributes of the region between the coastal plateau and the Winterberg escarpment of Ciskei. A raster-based geographical information system is derived for four separate study catchments and data on soil erosion and various soil erosion hazard indices are read into a computerised data matrix. The independent variables (soil erosion hazard indices) used in the study are selected on the basis of a review of the literature and on the availability of data in the Ciskei region. Multivariate analyses of the relationship between soil erosion and the various independent variables reveals that the primary variables affecting the spatial variation in soil erosion are land use, dominant soil type, geology, veld type and mean annual precipitation. All of these variables are readily quantifiable at the regional scale for large areas of Ciskei. An erosion hazard assessment model for use in central Ciskei is developed based on the results of the statistical analyses. The model is tested in separate study areas and is shown to provide an efficient method of identifying areas of differing susceptibility to soil erosion. The derived model is simple to operate and has input requirements which are easily met. It can be applied without the aid of computers, or where large areas are to be mapped it is well suited to computerisation
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- Authors: Weaver, Alex van Breda
- Date: 1989
- Subjects: Soil erosion -- South Africa -- Ciskei
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4792 , http://hdl.handle.net/10962/d1001892
- Description: The study examines the relationship between the spatial variation in soil erosion and various natural and anthropogenic attributes of the region between the coastal plateau and the Winterberg escarpment of Ciskei. A raster-based geographical information system is derived for four separate study catchments and data on soil erosion and various soil erosion hazard indices are read into a computerised data matrix. The independent variables (soil erosion hazard indices) used in the study are selected on the basis of a review of the literature and on the availability of data in the Ciskei region. Multivariate analyses of the relationship between soil erosion and the various independent variables reveals that the primary variables affecting the spatial variation in soil erosion are land use, dominant soil type, geology, veld type and mean annual precipitation. All of these variables are readily quantifiable at the regional scale for large areas of Ciskei. An erosion hazard assessment model for use in central Ciskei is developed based on the results of the statistical analyses. The model is tested in separate study areas and is shown to provide an efficient method of identifying areas of differing susceptibility to soil erosion. The derived model is simple to operate and has input requirements which are easily met. It can be applied without the aid of computers, or where large areas are to be mapped it is well suited to computerisation
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A survey of the curricula for the pre-service education of secondary school geography teachers in South Africa, with special reference to Transkei
- Authors: Mniki, Claribel Pumzile
- Date: 1987
- Subjects: Education -- Curricula , Education -- South Africa -- Transkei , Black people -- Education -- South Africa -- Transkei , Geography -- Study and teaching (Secondary) -- South Africa -- Transkei , Teachers -- Training of -- South Africa -- Transkei
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1340 , http://hdl.handle.net/10962/d1001406
- Description: Programmes designed for the pre-service education of secondary school geography teachers reflect the assumptions held by programme designers regarding the nature of education, teaching in general and geography teaching in particular. The general practice is that in universities, individual method lecturers design their programmes and in colleges within a department of education the programmes are centrally planned. Each programme focuses on a specific context. This, together with the autonomy enjoyed by university method lecturers in designing their courses, has resulted in the variations found in geography teacher education programmes. The evidence of this is found in the structure and duration of courses, the course content, the strategies used to educate teachers and the way in which the course is evaluated. This thesis is an attempt to establish consensus and divergence in pre-service education programmes for secondary school geography teachers regarding their organisation, specific knowledge imparted to student teachers; skills, values and attitudes developed. The pre-service education of secondary school geography teachers in South Africa is revealed in an analysis of views held by method lecturers, practising teachers in secondary schools, and student teachers and an analysis of course outlines , teaching practice assessment forms and geography method examination papers. Conclusions are drawn and recommendations made for improving the initial education of secondary school geography teachers in Transkei
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- Authors: Mniki, Claribel Pumzile
- Date: 1987
- Subjects: Education -- Curricula , Education -- South Africa -- Transkei , Black people -- Education -- South Africa -- Transkei , Geography -- Study and teaching (Secondary) -- South Africa -- Transkei , Teachers -- Training of -- South Africa -- Transkei
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1340 , http://hdl.handle.net/10962/d1001406
- Description: Programmes designed for the pre-service education of secondary school geography teachers reflect the assumptions held by programme designers regarding the nature of education, teaching in general and geography teaching in particular. The general practice is that in universities, individual method lecturers design their programmes and in colleges within a department of education the programmes are centrally planned. Each programme focuses on a specific context. This, together with the autonomy enjoyed by university method lecturers in designing their courses, has resulted in the variations found in geography teacher education programmes. The evidence of this is found in the structure and duration of courses, the course content, the strategies used to educate teachers and the way in which the course is evaluated. This thesis is an attempt to establish consensus and divergence in pre-service education programmes for secondary school geography teachers regarding their organisation, specific knowledge imparted to student teachers; skills, values and attitudes developed. The pre-service education of secondary school geography teachers in South Africa is revealed in an analysis of views held by method lecturers, practising teachers in secondary schools, and student teachers and an analysis of course outlines , teaching practice assessment forms and geography method examination papers. Conclusions are drawn and recommendations made for improving the initial education of secondary school geography teachers in Transkei
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A parser generator system to handle complete syntax
- Authors: Ossher, Harold Leon
- Date: 1982
- Subjects: Grammar, Comparative and general -- Syntax Parsing (Computer grammar) Programming languages (Electronic computers) Compilers (Computer programs)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4571 , http://hdl.handle.net/10962/d1002036
- Description: To define a language completely, it is necessary to define both its syntax and semantics. If these definitions are in a suitable form, the parser and code-generator of a compiler, respectively, can be generated from them. This thesis addresses the problem of syntax definition and automatic parser generation.
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- Authors: Ossher, Harold Leon
- Date: 1982
- Subjects: Grammar, Comparative and general -- Syntax Parsing (Computer grammar) Programming languages (Electronic computers) Compilers (Computer programs)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4571 , http://hdl.handle.net/10962/d1002036
- Description: To define a language completely, it is necessary to define both its syntax and semantics. If these definitions are in a suitable form, the parser and code-generator of a compiler, respectively, can be generated from them. This thesis addresses the problem of syntax definition and automatic parser generation.
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