Clustering algorithms and their effect on edge preservation in image compression
- Authors: Ndebele, Nothando Elizabeth
- Date: 2009
- Subjects: Image compression , Vector analysis , Cluster analysis , Cluster anaylsis -- Data processing , Algorithms
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5576 , http://hdl.handle.net/10962/d1008210 , Image compression , Vector analysis , Cluster analysis , Cluster anaylsis -- Data processing , Algorithms
- Description: Image compression aims to reduce the amount of data that is stored or transmitted for images. One technique that may be used to this end is vector quantization. Vectors may be used to represent images. Vector quantization reduces the number of vectors required for an image by representing a cluster of similar vectors by one typical vector that is part of a set of vectors referred to as the code book. For compression, for each image vector, only the closest codebook vector is stored or transmitted. For reconstruction, the image vectors are again replaced by the the closest codebook vectors. Hence vector quantization is a lossy compression technique and the quality of the reconstructed image depends strongly on the quality of the codebook. The design of the codebook is therefore an important part of the process. In this thesis we examine three clustering algorithms which can be used for codebook design in image compression: c-means (CM), fuzzy c-means (FCM) and learning vector quantization (LVQ). We give a description of these algorithms and their application to codebook design. Edges are an important part of the visual information contained in an image. It is essential therefore to use codebooks which allow an accurate representation of the edges. One of the shortcomings of using vector quantization is poor edge representation. We therefore carry out experiments using these algorithms to compare their edge preserving qualities. We also investigate the combination of these algorithms with classified vector quantization (CVQ) and the replication method (RM). Both these methods have been suggested as methods for improving edge representation. We use a cross validation approach to estimate the mean squared error to measure the performance of each of the algorithms and the edge preserving methods. The results reflect that the edges are less accurately represented than the non - edge areas when using CM, FCM and LVQ. The advantage of using CVQ is that the time taken for code book design is reduced particularly for CM and FCM. RM is found to be effective where the codebook is trained using a set that has larger proportions of edges than the test set.
- Full Text:
- Authors: Ndebele, Nothando Elizabeth
- Date: 2009
- Subjects: Image compression , Vector analysis , Cluster analysis , Cluster anaylsis -- Data processing , Algorithms
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5576 , http://hdl.handle.net/10962/d1008210 , Image compression , Vector analysis , Cluster analysis , Cluster anaylsis -- Data processing , Algorithms
- Description: Image compression aims to reduce the amount of data that is stored or transmitted for images. One technique that may be used to this end is vector quantization. Vectors may be used to represent images. Vector quantization reduces the number of vectors required for an image by representing a cluster of similar vectors by one typical vector that is part of a set of vectors referred to as the code book. For compression, for each image vector, only the closest codebook vector is stored or transmitted. For reconstruction, the image vectors are again replaced by the the closest codebook vectors. Hence vector quantization is a lossy compression technique and the quality of the reconstructed image depends strongly on the quality of the codebook. The design of the codebook is therefore an important part of the process. In this thesis we examine three clustering algorithms which can be used for codebook design in image compression: c-means (CM), fuzzy c-means (FCM) and learning vector quantization (LVQ). We give a description of these algorithms and their application to codebook design. Edges are an important part of the visual information contained in an image. It is essential therefore to use codebooks which allow an accurate representation of the edges. One of the shortcomings of using vector quantization is poor edge representation. We therefore carry out experiments using these algorithms to compare their edge preserving qualities. We also investigate the combination of these algorithms with classified vector quantization (CVQ) and the replication method (RM). Both these methods have been suggested as methods for improving edge representation. We use a cross validation approach to estimate the mean squared error to measure the performance of each of the algorithms and the edge preserving methods. The results reflect that the edges are less accurately represented than the non - edge areas when using CM, FCM and LVQ. The advantage of using CVQ is that the time taken for code book design is reduced particularly for CM and FCM. RM is found to be effective where the codebook is trained using a set that has larger proportions of edges than the test set.
- Full Text:
Collective forgiving
- Authors: Hamilton, Kelly
- Date: 2009
- Subjects: Forgiveness -- Philosophy Collective behavior -- Philosophy Retribution -- Philosophy Reconciliation -- Philosophy
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2709 , http://hdl.handle.net/10962/d1002839
- Description: Forgiveness is traditionally understood as a personal change of heart, in which an individual victim of a wrongdoing overcomes her resentment towards the perpetrator of that wrongdoing. Peter Strawson (1974) famously argued that resentment is a personal participant retributive reactive attitude, and the overcoming of such an attitude through forgiveness is itself a personal reactive attitude – in other words, forgiveness is an affective response to a wrongdoing by an individual victim, that is devoid of a retributive element. Because reactive attitudes are personal, it is argued that collectives – groups of individuals – cannot forgive, since collectives cannot, as collectives, hold reactive attitudes. I argue against this. I show that it is possible for collectives to hold attitudes in a way that is not reducible to individuals holding attitudes as individuals, and yet these attitudes still remain personal. Individuals exist within communities, and are interdependent on one another. Much of an individual‟s beliefs and attitudes depend on the collectives that she is a part of. I argue that an attitude is collective when it is deemed to be the appropriate attitude for members of the collective to hold. Members of the collective will take this attitude on as their own insofar as they identify themselves as members of the collective. Individuals hold the attitude, making the attitude personal, but since the individuals hold the attitude in virtue of their membership to a collective, the attitude is also collective. Given that forgiveness is itself a reactive attitude, and that collectives can hold attitudes, I argue that it is possible for a collective to forgive. Members of a collective will come to forgive when forgiveness is held up as the appropriate attitude for them, and once enough members have taken on the attitude of forgiveness as their own attitude, a collective can be said to have forgiven.
- Full Text:
- Authors: Hamilton, Kelly
- Date: 2009
- Subjects: Forgiveness -- Philosophy Collective behavior -- Philosophy Retribution -- Philosophy Reconciliation -- Philosophy
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2709 , http://hdl.handle.net/10962/d1002839
- Description: Forgiveness is traditionally understood as a personal change of heart, in which an individual victim of a wrongdoing overcomes her resentment towards the perpetrator of that wrongdoing. Peter Strawson (1974) famously argued that resentment is a personal participant retributive reactive attitude, and the overcoming of such an attitude through forgiveness is itself a personal reactive attitude – in other words, forgiveness is an affective response to a wrongdoing by an individual victim, that is devoid of a retributive element. Because reactive attitudes are personal, it is argued that collectives – groups of individuals – cannot forgive, since collectives cannot, as collectives, hold reactive attitudes. I argue against this. I show that it is possible for collectives to hold attitudes in a way that is not reducible to individuals holding attitudes as individuals, and yet these attitudes still remain personal. Individuals exist within communities, and are interdependent on one another. Much of an individual‟s beliefs and attitudes depend on the collectives that she is a part of. I argue that an attitude is collective when it is deemed to be the appropriate attitude for members of the collective to hold. Members of the collective will take this attitude on as their own insofar as they identify themselves as members of the collective. Individuals hold the attitude, making the attitude personal, but since the individuals hold the attitude in virtue of their membership to a collective, the attitude is also collective. Given that forgiveness is itself a reactive attitude, and that collectives can hold attitudes, I argue that it is possible for a collective to forgive. Members of a collective will come to forgive when forgiveness is held up as the appropriate attitude for them, and once enough members have taken on the attitude of forgiveness as their own attitude, a collective can be said to have forgiven.
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Comparing and contrasting liberal, communitarian and feminist approaches to resolving tensions between customary and constitutional law: the case of polygamy in Swaziland
- Authors: Manson, Katherine Elizabeth
- Date: 2009
- Subjects: Human rights -- Swaziland Constitutional law -- Swaziland Customary law -- Swaziland Culture and law -- Swaziland Women's rights -- Swaziland Sex discrimination against women -- Swaziland Polygamy -- Swaziland Liberalism Communitarianism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2801 , http://hdl.handle.net/10962/d1003011
- Description: Tensions between the individual rights and freedoms found in constitutional bills of rights and the traditionally prescribed social roles and positions articulated in African customary law systems have often been characterised as tensions between communitarian and liberal philosophies. In particular, the notion of gender equality, which is often a feature of the protections offered by constitutional bills of rights, is seen to be in direct opposition to the overtly patriarchal character of many African customs and traditions. This thesis looks specifically at polygamy, long and widely considered in the West to be an oppressive practice premised on the assumed inferiority of women. The analysis considers the implications of polygamy in a particular cultural context, that of the Kingdom of Swaziland, where the newly instituted constitution is often seen to be incompatible with many aspects of Swazi customary law. Here, the tension between the constitutional commitment to gender equality and the persistence of polygamy as a seemingly discriminatory cultural practice forms a lens through which to view the debate as a whole. The theoretical analysis is supplemented by empirical research sourced from local media archives and in-depth interviews conducted with twelve Swazi women, both unmarried and married in polygamous relationships. Communitarian and liberal approaches to resolving this tension are compared, contrasted and finally critiqued from a feminist standpoint. The feminist critique of both communitarianism and liberalism implies that neither ideology promises much for women and affirms the relatively recent feminist suggestion that the key to resolving tensions between constitutional and customary law in general, and to uplifting the social/legal status of women in particular lies in the enhancement of women’s democratic participation and the improvement of women’s decision-making powers.
- Full Text:
- Authors: Manson, Katherine Elizabeth
- Date: 2009
- Subjects: Human rights -- Swaziland Constitutional law -- Swaziland Customary law -- Swaziland Culture and law -- Swaziland Women's rights -- Swaziland Sex discrimination against women -- Swaziland Polygamy -- Swaziland Liberalism Communitarianism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2801 , http://hdl.handle.net/10962/d1003011
- Description: Tensions between the individual rights and freedoms found in constitutional bills of rights and the traditionally prescribed social roles and positions articulated in African customary law systems have often been characterised as tensions between communitarian and liberal philosophies. In particular, the notion of gender equality, which is often a feature of the protections offered by constitutional bills of rights, is seen to be in direct opposition to the overtly patriarchal character of many African customs and traditions. This thesis looks specifically at polygamy, long and widely considered in the West to be an oppressive practice premised on the assumed inferiority of women. The analysis considers the implications of polygamy in a particular cultural context, that of the Kingdom of Swaziland, where the newly instituted constitution is often seen to be incompatible with many aspects of Swazi customary law. Here, the tension between the constitutional commitment to gender equality and the persistence of polygamy as a seemingly discriminatory cultural practice forms a lens through which to view the debate as a whole. The theoretical analysis is supplemented by empirical research sourced from local media archives and in-depth interviews conducted with twelve Swazi women, both unmarried and married in polygamous relationships. Communitarian and liberal approaches to resolving this tension are compared, contrasted and finally critiqued from a feminist standpoint. The feminist critique of both communitarianism and liberalism implies that neither ideology promises much for women and affirms the relatively recent feminist suggestion that the key to resolving tensions between constitutional and customary law in general, and to uplifting the social/legal status of women in particular lies in the enhancement of women’s democratic participation and the improvement of women’s decision-making powers.
- Full Text:
Conflict, contradiction and crisis: an analysis of the politics of AIDS policy in post-Apartheid South Africa
- Authors: Fletcher, Haley Kim
- Date: 2009
- Subjects: AIDS (Disease) -- Political aspects -- Africa, Southern AIDS (Disease) -- Political aspects -- South Africa AIDS (Disease) -- Government policy -- South Africa Africa -- Politics and government
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2775 , http://hdl.handle.net/10962/d1002985
- Description: Despite the profound impacts of HIV and AIDS on all sectors of South African society, governmental responses to the AIDS epidemic have been inundated with contradiction, conflict and contestation. Though governmental leaders have justified not funding HIV treatment programs because they believe that poverty needs to be dealt with first, social spending has been slashed as part of an adherence to a neo-liberal economic model. Though it would seem that the government would seem to have everything to gain by establishing a cooperative relationship with non-governmental actors regarding the epidemic, the relationship between the government and non-governmental actors has instead been described as nothing short of hostile. Though the government enthusiastically backed Virodene, a supposed treatment for AIDS that turned out to be no more than an industrial solvent, other ‘scientifically backed’ AIDS treatments have been treated with caution and skepticism – to the point where the government even refused to provide funding for programs to prevent mother to child transmission of the virus. And perhaps the most perplexing is that although widely respected for his intellect and cool demeanor, former President Mbeki chose to risk his political career on the AIDS issue by shunning away from the mainstream consensus on the biomedical causes of the epidemic and instead surrounded himself and sought advice from AIDS ‘dissidents’ This thesis will seek explanations for these apparent contradictions. Using Bourdieu’s (1986) typology of capitals, it will build on an argument put forward by Helen Schneider (2002): from the South African government’s perspective, the contestation regarding HIV and AIDS policy and implementation is over symbolic capital, or the right to legitimately hold and exercise political power regarding the epidemic. Though this argument helps explain the conflictual relationship between the government and non-governmental actors regarding the AIDS crisis, in order to understand the perplexing contradictions within the governmental policy response, the political context of policy formation must first be taken into consideration.
- Full Text:
- Authors: Fletcher, Haley Kim
- Date: 2009
- Subjects: AIDS (Disease) -- Political aspects -- Africa, Southern AIDS (Disease) -- Political aspects -- South Africa AIDS (Disease) -- Government policy -- South Africa Africa -- Politics and government
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2775 , http://hdl.handle.net/10962/d1002985
- Description: Despite the profound impacts of HIV and AIDS on all sectors of South African society, governmental responses to the AIDS epidemic have been inundated with contradiction, conflict and contestation. Though governmental leaders have justified not funding HIV treatment programs because they believe that poverty needs to be dealt with first, social spending has been slashed as part of an adherence to a neo-liberal economic model. Though it would seem that the government would seem to have everything to gain by establishing a cooperative relationship with non-governmental actors regarding the epidemic, the relationship between the government and non-governmental actors has instead been described as nothing short of hostile. Though the government enthusiastically backed Virodene, a supposed treatment for AIDS that turned out to be no more than an industrial solvent, other ‘scientifically backed’ AIDS treatments have been treated with caution and skepticism – to the point where the government even refused to provide funding for programs to prevent mother to child transmission of the virus. And perhaps the most perplexing is that although widely respected for his intellect and cool demeanor, former President Mbeki chose to risk his political career on the AIDS issue by shunning away from the mainstream consensus on the biomedical causes of the epidemic and instead surrounded himself and sought advice from AIDS ‘dissidents’ This thesis will seek explanations for these apparent contradictions. Using Bourdieu’s (1986) typology of capitals, it will build on an argument put forward by Helen Schneider (2002): from the South African government’s perspective, the contestation regarding HIV and AIDS policy and implementation is over symbolic capital, or the right to legitimately hold and exercise political power regarding the epidemic. Though this argument helps explain the conflictual relationship between the government and non-governmental actors regarding the AIDS crisis, in order to understand the perplexing contradictions within the governmental policy response, the political context of policy formation must first be taken into consideration.
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Contextualizing the NCS through the use of school gardens in the Butterworth area
- Authors: Rasi, Nandi
- Date: 2009
- Subjects: South African National Biodiversity Institute , Environmental education -- South Africa , School gardens -- South Africa -- Butterworth , Gardening -- Study and teaching (Elementary) -- South Africa -- Butterworth , Environmental education -- Study and teaching (Elementary) -- South Africa -- Butterworth , Teacher participation in curriculum planning -- South Africa -- Butterworth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1464 , http://hdl.handle.net/10962/d1003345
- Description: The research focuses on how teachers can use school gardens sponsored by South African National Biodiversity Institute as resource materials for teaching and learning. The study also focused on how teachers can integrate local knowledge into the school curriculum. The setting of the research is Zizamele Senior Primary School situated in Zizamele community in Butterworth in the Eastern Cape. The study is designed in portfolio format. It consists of three separate studies: a contextual profile; a stakeholder analysis; and a small-scale action research project, which build on each other. By developing a contextual profile of the research site, and the school community and school gardens project, I was able to collect information that informed the stakeholder analysis and the action research study. Data for the contextual profile was gathered by using a variety of data gathering techniques like questionnaires and interviews. The findings were that: the study area is characterized by socio-economic issues like poverty, unemployment, drug abuse and crime. This requires that the people of the area take responsibility in addressing some of the problems by being involved and knowing where to report issues. The second study, which is the stakeholder analysis, was done to mobilize stakeholders’ contributions to the gardens project in Zizamele School, sponsored by the South African National Biodiversity Institute. Data was collected at meetings and workshops in the schools through interviews. Findings indicated that different stakeholders had various contributions to make and that they were prepared to work with the school and with each other to develop the school garden and the learning potential of the school garden. This paved the way for the small scale action research case study that would follow. The last study, the small scale action research, was undertaken in the same school, Zizamele School, and focused on investigating ways of integrating local knowledge into the curriculum and how teachers use the gardens as resource for teaching and learning, with reference to Life Orientation Learning Area. Data was collected by interviews, questionnaires and worksheets. The study involved two teachers who worked with me on the action research and Grade 5 and 6 learners, as well as some of the community stakeholders. The main finding of the action researched showed the potential for involving community members in the process of integrating local knowledge as a way of implementing aspects of the Life Orientation curriculum requirements. The three studies link with each other, and show that to start with an action research project, one needs to understand the context, and the roles of different stakeholders, and how they might contribute to the programmes in the school. Findings showed that teachers could use gardens as resource materials for teaching and learning, and that they could bring in local knowledge to the school curriculum.
- Full Text:
- Authors: Rasi, Nandi
- Date: 2009
- Subjects: South African National Biodiversity Institute , Environmental education -- South Africa , School gardens -- South Africa -- Butterworth , Gardening -- Study and teaching (Elementary) -- South Africa -- Butterworth , Environmental education -- Study and teaching (Elementary) -- South Africa -- Butterworth , Teacher participation in curriculum planning -- South Africa -- Butterworth
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1464 , http://hdl.handle.net/10962/d1003345
- Description: The research focuses on how teachers can use school gardens sponsored by South African National Biodiversity Institute as resource materials for teaching and learning. The study also focused on how teachers can integrate local knowledge into the school curriculum. The setting of the research is Zizamele Senior Primary School situated in Zizamele community in Butterworth in the Eastern Cape. The study is designed in portfolio format. It consists of three separate studies: a contextual profile; a stakeholder analysis; and a small-scale action research project, which build on each other. By developing a contextual profile of the research site, and the school community and school gardens project, I was able to collect information that informed the stakeholder analysis and the action research study. Data for the contextual profile was gathered by using a variety of data gathering techniques like questionnaires and interviews. The findings were that: the study area is characterized by socio-economic issues like poverty, unemployment, drug abuse and crime. This requires that the people of the area take responsibility in addressing some of the problems by being involved and knowing where to report issues. The second study, which is the stakeholder analysis, was done to mobilize stakeholders’ contributions to the gardens project in Zizamele School, sponsored by the South African National Biodiversity Institute. Data was collected at meetings and workshops in the schools through interviews. Findings indicated that different stakeholders had various contributions to make and that they were prepared to work with the school and with each other to develop the school garden and the learning potential of the school garden. This paved the way for the small scale action research case study that would follow. The last study, the small scale action research, was undertaken in the same school, Zizamele School, and focused on investigating ways of integrating local knowledge into the curriculum and how teachers use the gardens as resource for teaching and learning, with reference to Life Orientation Learning Area. Data was collected by interviews, questionnaires and worksheets. The study involved two teachers who worked with me on the action research and Grade 5 and 6 learners, as well as some of the community stakeholders. The main finding of the action researched showed the potential for involving community members in the process of integrating local knowledge as a way of implementing aspects of the Life Orientation curriculum requirements. The three studies link with each other, and show that to start with an action research project, one needs to understand the context, and the roles of different stakeholders, and how they might contribute to the programmes in the school. Findings showed that teachers could use gardens as resource materials for teaching and learning, and that they could bring in local knowledge to the school curriculum.
- Full Text:
Continuous assessment in Oshikwanyama: a case study
- Nghiueuelekuah, Soini Tuhafeni
- Authors: Nghiueuelekuah, Soini Tuhafeni
- Date: 2009
- Subjects: Educational tests and measurements -- Namibia -- Case studies Kuanyama language -- Namibia -- Case studies Kuanyama language -- Study and teaching -- Namibia -- Case studies Language and education -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1465 , http://hdl.handle.net/10962/d1003346
- Description: This study is about Continuous Assessment (CA) in teaching and learning, a new concept and approach in independent Namibia. The country's education system was reformed shortly after independence in 1990 to fulfill the intention for Education for All. The Namibian education system then moved from a behaviorist to constructivist philosophy of education. The move made from one philosophy to another resulted in many changes in teaching and learning including changes in assessment in education. CA is born out of a constructivist philosophy. It is believed to facilitate learning with understanding. In this study I explored the understanding of Oshikwanyama teachers and their practice of CA in teaching and learning. Interviews, classroom observations and document analysis were used. The research focused on 10 participants in the Ohangwena and Oshana regions. The participants ranged from a Head of Department to members of the curriculum panel, subject advisors and Oshikwanyama subject facilitators as well as teachers at the classroom level. It was revealed that generally speaking, CA as a term is understood, but the practice is not well implemented. In the practice of CA, instead of learners being assessed for further learning, the emphasis is on scored marks without further assistance in learning. Further, the collection of marks during CA is often seen as largely for the purpose of contributing to the marks for summative final marks. Informal assessment which is part of CA was not given attention, which is a key factor preventing the effective use of CA in teaching and learning. Methods such as marking grids that are provided in the syllabus, as well as portfolios and learners' profiles, were not mentioned in the interviews nor observed as being in use. Participants in the study did acknowledge that they did not fully understand how best to implement CA. Overall, the evidence pointed to a conclusion that the identified shortcomings in the implementation of formative assessment is limiting the realization of the rich potential for CA as a day-to-day tool to facilitate learning for understanding in the observed classes.
- Full Text:
- Authors: Nghiueuelekuah, Soini Tuhafeni
- Date: 2009
- Subjects: Educational tests and measurements -- Namibia -- Case studies Kuanyama language -- Namibia -- Case studies Kuanyama language -- Study and teaching -- Namibia -- Case studies Language and education -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1465 , http://hdl.handle.net/10962/d1003346
- Description: This study is about Continuous Assessment (CA) in teaching and learning, a new concept and approach in independent Namibia. The country's education system was reformed shortly after independence in 1990 to fulfill the intention for Education for All. The Namibian education system then moved from a behaviorist to constructivist philosophy of education. The move made from one philosophy to another resulted in many changes in teaching and learning including changes in assessment in education. CA is born out of a constructivist philosophy. It is believed to facilitate learning with understanding. In this study I explored the understanding of Oshikwanyama teachers and their practice of CA in teaching and learning. Interviews, classroom observations and document analysis were used. The research focused on 10 participants in the Ohangwena and Oshana regions. The participants ranged from a Head of Department to members of the curriculum panel, subject advisors and Oshikwanyama subject facilitators as well as teachers at the classroom level. It was revealed that generally speaking, CA as a term is understood, but the practice is not well implemented. In the practice of CA, instead of learners being assessed for further learning, the emphasis is on scored marks without further assistance in learning. Further, the collection of marks during CA is often seen as largely for the purpose of contributing to the marks for summative final marks. Informal assessment which is part of CA was not given attention, which is a key factor preventing the effective use of CA in teaching and learning. Methods such as marking grids that are provided in the syllabus, as well as portfolios and learners' profiles, were not mentioned in the interviews nor observed as being in use. Participants in the study did acknowledge that they did not fully understand how best to implement CA. Overall, the evidence pointed to a conclusion that the identified shortcomings in the implementation of formative assessment is limiting the realization of the rich potential for CA as a day-to-day tool to facilitate learning for understanding in the observed classes.
- Full Text:
Contributions to the study of a class of optimal control problems on the matrix lie group SO(3)
- Authors: Rodgerson, Joanne Kelly
- Date: 2009 , 2013-07-12
- Subjects: Matrix groups , Lie groups , Maximum principles (Mathematics) , Elliptic functions , Extremal problems (Mathematics)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5421 , http://hdl.handle.net/10962/d1007199 , Matrix groups , Lie groups , Maximum principles (Mathematics) , Elliptic functions , Extremal problems (Mathematics)
- Description: The purpose of this thesis is to investigate a class of four left-invariant optimal control problems on the special orthogonal group SO(3). The set of all control-affine left-invariant control systems on SO(3) can, without loss, be reduced to a class of four typical controllable left-invariant control systems on SO(3) . The left-invariant optimal control problem on SO(3) involves finding a trajectory-control pair on SO (3), which minimizes a cost functional, and satisfies the given dynamical constraints and boundary conditions in a fixed time. The problem is lifted to the cotangent bundle T*SO(3) = SO(3) x so (3)* using the optimal Hamiltonian on so(3)*, where the maximum principle yields the optimal control. In a contribution to the study of this class of optimal control problems on SO(3), the extremal equations on so(3)* (ident ified with JR3) are integrated via elliptic functions to obtain explicit expressions for the solution curves in each typical case. The energy-Casimir method is used to give sufficient conditions for non-linear stability of the equilibrium states. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Authors: Rodgerson, Joanne Kelly
- Date: 2009 , 2013-07-12
- Subjects: Matrix groups , Lie groups , Maximum principles (Mathematics) , Elliptic functions , Extremal problems (Mathematics)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5421 , http://hdl.handle.net/10962/d1007199 , Matrix groups , Lie groups , Maximum principles (Mathematics) , Elliptic functions , Extremal problems (Mathematics)
- Description: The purpose of this thesis is to investigate a class of four left-invariant optimal control problems on the special orthogonal group SO(3). The set of all control-affine left-invariant control systems on SO(3) can, without loss, be reduced to a class of four typical controllable left-invariant control systems on SO(3) . The left-invariant optimal control problem on SO(3) involves finding a trajectory-control pair on SO (3), which minimizes a cost functional, and satisfies the given dynamical constraints and boundary conditions in a fixed time. The problem is lifted to the cotangent bundle T*SO(3) = SO(3) x so (3)* using the optimal Hamiltonian on so(3)*, where the maximum principle yields the optimal control. In a contribution to the study of this class of optimal control problems on SO(3), the extremal equations on so(3)* (ident ified with JR3) are integrated via elliptic functions to obtain explicit expressions for the solution curves in each typical case. The energy-Casimir method is used to give sufficient conditions for non-linear stability of the equilibrium states. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
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Coping with xenophobia : Senegalese migrants in Port Elizabeth
- Authors: Barbali, Silvana Claudia
- Date: 2009
- Subjects: Xenophobia -- South Africa -- Port Elizabeth Migrant labor -- South Africa -- Port Elizabeth Immigrants -- South Africa -- Port Elizabeth Foreign workers -- South Africa -- Port Elizabeth Aliens -- South Africa -- Social conditions Immigrants -- Africa -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2102 , http://hdl.handle.net/10962/d1002665
- Description: This thesis seeks to investigate Senegalese migrants' experiences of xenophobia in South Africa. It explores prevailing theories used to explain the phenomenon of xenophobia and uses data collected via anthropological fieldwork to support arguments made. It is argued that a culture of migration in Senegal and the significance of migration as a rite of passage in Senegalese masculinity assists migrants to orientate themselves in host countries, and influences the way Senegalese are „received‟ by South Africans. In addition, Senegalese Islam (Sufi Orientation), which organises its members into brotherhoods, assists in the social integration of Senegalese men in Port Elizabeth. The men belong to the Mouride Brotherhood and the thesis shows how membership to the brotherhood provides a strong network of support for migrant men without resulting in the enclaving of the men in the broader social and economic context of Port Elizabeth. This has important implications for the individual and collective migration experience of Senegalese and influences the men's creation of meaning in their experiences as migrants. The thesis makes use of the concept of transnationalism to analyse the complex and multifaceted nature of transnational migration, arguing that migration experiences are influenced by a range of transnational factors and is deeply culturally influenced. The research suggests that migration experts and government departments in South Africa should take these complexities into account when formulating new programmes and policies for migrants.
- Full Text:
- Authors: Barbali, Silvana Claudia
- Date: 2009
- Subjects: Xenophobia -- South Africa -- Port Elizabeth Migrant labor -- South Africa -- Port Elizabeth Immigrants -- South Africa -- Port Elizabeth Foreign workers -- South Africa -- Port Elizabeth Aliens -- South Africa -- Social conditions Immigrants -- Africa -- Social conditions
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2102 , http://hdl.handle.net/10962/d1002665
- Description: This thesis seeks to investigate Senegalese migrants' experiences of xenophobia in South Africa. It explores prevailing theories used to explain the phenomenon of xenophobia and uses data collected via anthropological fieldwork to support arguments made. It is argued that a culture of migration in Senegal and the significance of migration as a rite of passage in Senegalese masculinity assists migrants to orientate themselves in host countries, and influences the way Senegalese are „received‟ by South Africans. In addition, Senegalese Islam (Sufi Orientation), which organises its members into brotherhoods, assists in the social integration of Senegalese men in Port Elizabeth. The men belong to the Mouride Brotherhood and the thesis shows how membership to the brotherhood provides a strong network of support for migrant men without resulting in the enclaving of the men in the broader social and economic context of Port Elizabeth. This has important implications for the individual and collective migration experience of Senegalese and influences the men's creation of meaning in their experiences as migrants. The thesis makes use of the concept of transnationalism to analyse the complex and multifaceted nature of transnational migration, arguing that migration experiences are influenced by a range of transnational factors and is deeply culturally influenced. The research suggests that migration experts and government departments in South Africa should take these complexities into account when formulating new programmes and policies for migrants.
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Correction, addition and deletion : memory and its function in creating "visual narratives" (and identity) in photographic art
- Authors: Geyer, Xanthe Amanda
- Date: 2009
- Subjects: Botha, Lien, 1961- Photography -- Social aspects Memory in art Photography -- Philosophy Identity (Philosophical concept)
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2402 , http://hdl.handle.net/10962/d1002198
- Description: With this dissertation I propose to investigate critical theories dealing with memory and its role in photography. The function of memory is a well discussed and analysed topic within the ambit of historical research. Drawing from theoretical texts by critical theorists, namely, Roland Barthes, Annette Kuhn and Marianne Hirsch, I will critically address the function of memory in the understanding of photography; particularly how photographs have the ability to construct our identity in terms of history and narrative. I will study the content of memory in relation to visual images, focusing on what is remembered, what is suppressed, and finally, what is transformed when viewing an image. By doing so, I will consider whether or not still photographs have the ability to construct the past in a narrative form that is intrinsic to its medium. This consideration will be undertaken with specific reference to the works of contemporary South African artist Lien Botha. Special attention will be directed to her series of work entitled Amendment (2006), a series which permits me in turn, to deal with issues pertaining to memory and “visual narrative” which I have explored in my own professional art practice namely, Memory Boxes, Back Stories, Faces of You and Me, Memories Re-layered and Ghostly Remnants.
- Full Text:
- Authors: Geyer, Xanthe Amanda
- Date: 2009
- Subjects: Botha, Lien, 1961- Photography -- Social aspects Memory in art Photography -- Philosophy Identity (Philosophical concept)
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2402 , http://hdl.handle.net/10962/d1002198
- Description: With this dissertation I propose to investigate critical theories dealing with memory and its role in photography. The function of memory is a well discussed and analysed topic within the ambit of historical research. Drawing from theoretical texts by critical theorists, namely, Roland Barthes, Annette Kuhn and Marianne Hirsch, I will critically address the function of memory in the understanding of photography; particularly how photographs have the ability to construct our identity in terms of history and narrative. I will study the content of memory in relation to visual images, focusing on what is remembered, what is suppressed, and finally, what is transformed when viewing an image. By doing so, I will consider whether or not still photographs have the ability to construct the past in a narrative form that is intrinsic to its medium. This consideration will be undertaken with specific reference to the works of contemporary South African artist Lien Botha. Special attention will be directed to her series of work entitled Amendment (2006), a series which permits me in turn, to deal with issues pertaining to memory and “visual narrative” which I have explored in my own professional art practice namely, Memory Boxes, Back Stories, Faces of You and Me, Memories Re-layered and Ghostly Remnants.
- Full Text:
Critical reflective teaching practice in three mathematics teachers
- Authors: Luwango, Luiya
- Date: 2009
- Subjects: Education (Secondary) -- Namibia Mathematics teachers -- Training of - -Namibia Mathematics -- Study and teaching (Secondary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1485 , http://hdl.handle.net/10962/d1003366
- Description: This qualitative study reports on critical reflective teaching by three mathematics teachers and how it shapes their classroom practice. The study was carried out in three secondary schools in Rundu in northern Namibia. The study employed a case study method. The selection of teachers was based on their rich practical professional knowledge and exemplary teaching practices. Data collection and analysis was done through an interpretive approach. Interviews and document analyses were the two research tools used, not only for the collection of data but for triangulation also. Interpretations of the findings were validated through member checking. Critical reflective teaching involves thought and action, and it raises teachers’ consciousness of what they do. Through critical reflective practice, teachers scrutinize their beliefs and knowledge of the subject and their practice. Furthermore critical reflective practice may get teachers into a disposition to find alternatives to improve their teaching. In this study, the findings are that participants reflect extensively on their classroom practice. The teachers pointed out that reflection on practice enables them to analyse and evaluate their teaching in line with effective mathematics teaching. They emphasised that critical reflection leads to the identification of weaknesses in teachers’ classroom practice. This culminates in better planning whereby alternative approaches to teaching are exercised. Because of its potential to improve teaching and enhance professional development it is therefore recommended that mathematics teachers be exposed to skills that enhance critical reflective teaching practice. Teachers need to familiarise themselves with the concept of critical reflective teaching in mathematics to meet the demands of superior quality teaching.
- Full Text:
- Authors: Luwango, Luiya
- Date: 2009
- Subjects: Education (Secondary) -- Namibia Mathematics teachers -- Training of - -Namibia Mathematics -- Study and teaching (Secondary) -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1485 , http://hdl.handle.net/10962/d1003366
- Description: This qualitative study reports on critical reflective teaching by three mathematics teachers and how it shapes their classroom practice. The study was carried out in three secondary schools in Rundu in northern Namibia. The study employed a case study method. The selection of teachers was based on their rich practical professional knowledge and exemplary teaching practices. Data collection and analysis was done through an interpretive approach. Interviews and document analyses were the two research tools used, not only for the collection of data but for triangulation also. Interpretations of the findings were validated through member checking. Critical reflective teaching involves thought and action, and it raises teachers’ consciousness of what they do. Through critical reflective practice, teachers scrutinize their beliefs and knowledge of the subject and their practice. Furthermore critical reflective practice may get teachers into a disposition to find alternatives to improve their teaching. In this study, the findings are that participants reflect extensively on their classroom practice. The teachers pointed out that reflection on practice enables them to analyse and evaluate their teaching in line with effective mathematics teaching. They emphasised that critical reflection leads to the identification of weaknesses in teachers’ classroom practice. This culminates in better planning whereby alternative approaches to teaching are exercised. Because of its potential to improve teaching and enhance professional development it is therefore recommended that mathematics teachers be exposed to skills that enhance critical reflective teaching practice. Teachers need to familiarise themselves with the concept of critical reflective teaching in mathematics to meet the demands of superior quality teaching.
- Full Text:
Determinism and reactive attitudes: reflections on our alleged unrenounceable commitments
- Authors: Kelland, Lindsay-Ann
- Date: 2009
- Subjects: Free will and determinism Responsibility
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2713 , http://hdl.handle.net/10962/d1002843
- Description: There seems to exist a tension between our metaphysical and phenomenological commitments in the free will debate. On the one hand, I argue that at the metaphysical level we cannot coherently defend the belief that we are morally responsible in the sense that we deserve to be rewarded and punished for our actions, where desert-entailing moral responsibility is the primary understanding of moral responsibility presupposed in the free will debate. I argue that we are responsible for our actions but only in the weaker sense, termed ‘attributability’ by Gary Watson. On the other hand, we are allegedly unrenounceably committed at the phenomenological level to conceiving of, and treating, ourselves and one another as morally responsible beings in the desert-entailing sense. P. F. Strawson famously defends this claim in his seminal work, ‘Freedom and Resentment’. In my thesis I will set out this tension by exploring both commitments in turn. I then aim to show that the tension can be dissolved by arguing, contra P. F. Strawson, that our phenomenological commitment is not in fact unrenounceable. The dissolution of this tension entails, I argue, that we must examine our conception of self and other. We must explore the implications of adopting a position which denies that we are morally responsible beings for our life-hopes, personal feelings, inter-personal relationships and projects. Most importantly, I argue that we must renounce our current retributive condemnatory practices which are based on the unjustified belief that we are morally responsible beings.
- Full Text:
- Authors: Kelland, Lindsay-Ann
- Date: 2009
- Subjects: Free will and determinism Responsibility
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2713 , http://hdl.handle.net/10962/d1002843
- Description: There seems to exist a tension between our metaphysical and phenomenological commitments in the free will debate. On the one hand, I argue that at the metaphysical level we cannot coherently defend the belief that we are morally responsible in the sense that we deserve to be rewarded and punished for our actions, where desert-entailing moral responsibility is the primary understanding of moral responsibility presupposed in the free will debate. I argue that we are responsible for our actions but only in the weaker sense, termed ‘attributability’ by Gary Watson. On the other hand, we are allegedly unrenounceably committed at the phenomenological level to conceiving of, and treating, ourselves and one another as morally responsible beings in the desert-entailing sense. P. F. Strawson famously defends this claim in his seminal work, ‘Freedom and Resentment’. In my thesis I will set out this tension by exploring both commitments in turn. I then aim to show that the tension can be dissolved by arguing, contra P. F. Strawson, that our phenomenological commitment is not in fact unrenounceable. The dissolution of this tension entails, I argue, that we must examine our conception of self and other. We must explore the implications of adopting a position which denies that we are morally responsible beings for our life-hopes, personal feelings, inter-personal relationships and projects. Most importantly, I argue that we must renounce our current retributive condemnatory practices which are based on the unjustified belief that we are morally responsible beings.
- Full Text:
Developing an ionospheric map for South Africa
- Authors: Okoh, Daniel Izuikeninachi
- Date: 2009
- Subjects: Ionosphere -- South Africa , Shortwave radio , Ionospheric electron density -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5459 , http://hdl.handle.net/10962/d1005244 , Ionosphere -- South Africa , Shortwave radio , Ionospheric electron density -- South Africa
- Description: This thesis describes the development of an ionospheric map for the South African region using the current available resources. The International Reference Ionosphere (IRI) model, the South African Bottomside Ionospheric Model (SABIM), and measurements from ionosondes in the South African Ionosonde Network, were incorporated into the map. An accurate ionospheric map depicting the foF2 and hmF2 parameters as well as electron density profiles at any location within South Africa is a useful tool for, amongst others, High Frequency (HF) communicators and space weather centers. A major product of the work is software, written in MATLAB, which produces spatial and temporal representations of the South African ionosphere. The map was validated and demonstrated for practical application, since a significant aim of the project was to make the map as applicable as possible. It is hoped that the map will find immense application in HF radio communication industries, research industries, aviation industries, and other industries that make use of Earth-Space systems. A potential user of the map is GrinTek Ewation (GEW) who is currently evaluating it for their purposes
- Full Text:
- Authors: Okoh, Daniel Izuikeninachi
- Date: 2009
- Subjects: Ionosphere -- South Africa , Shortwave radio , Ionospheric electron density -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5459 , http://hdl.handle.net/10962/d1005244 , Ionosphere -- South Africa , Shortwave radio , Ionospheric electron density -- South Africa
- Description: This thesis describes the development of an ionospheric map for the South African region using the current available resources. The International Reference Ionosphere (IRI) model, the South African Bottomside Ionospheric Model (SABIM), and measurements from ionosondes in the South African Ionosonde Network, were incorporated into the map. An accurate ionospheric map depicting the foF2 and hmF2 parameters as well as electron density profiles at any location within South Africa is a useful tool for, amongst others, High Frequency (HF) communicators and space weather centers. A major product of the work is software, written in MATLAB, which produces spatial and temporal representations of the South African ionosphere. The map was validated and demonstrated for practical application, since a significant aim of the project was to make the map as applicable as possible. It is hoped that the map will find immense application in HF radio communication industries, research industries, aviation industries, and other industries that make use of Earth-Space systems. A potential user of the map is GrinTek Ewation (GEW) who is currently evaluating it for their purposes
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Development of a neural network based model for predicting the occurrence of spread F within the Brazilian sector
- Authors: Paradza, Masimba Wellington
- Date: 2009
- Subjects: Neural networks (Computer science) , Ionosphere , F region
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5460 , http://hdl.handle.net/10962/d1005245 , Neural networks (Computer science) , Ionosphere , F region
- Description: Spread F is a phenomenon of the ionosphere in which the pulses returned from the ionosphere are of a much greater duration than the transmitted ones. The occurrence of spread F can be predicted using the technique of Neural Networks (NNs). This thesis presents the development and evaluation of NN based models (two single station models and a regional model) for predicting the occurrence of spread F over selected stations within the Brazilian sector. The input space for the NNs included the day number (seasonal variation), hour (diurnal variation), sunspot number (measure of the solar activity), magnetic index (measure of the magnetic activity) and magnetic position (latitude, magnetic declination and inclination). Twelve years of spread F data measured during 1978 to 1989 inclusively at the equatorial site Fortaleza and low latitude site Cachoeira Paulista are used in the development of an input space and NN architecture for the NN models. Spread F data that is believed to be related to plasma bubble developments (range spread F) were used in the development of the models while those associated with narrow spectrum irregularities that occur near the F layer (frequency spread F) were excluded. The results of the models show the dependency of the probability of spread F as a function of local time, season and latitude. The models also illustrate some characteristics of spread F such as the onset and peak occurrence of spread F as a function of distance from the equator. Results from these models are presented in this thesis and compared to measured data and to modelled data obtained with an empirical model developed for the same purpose.
- Full Text:
- Authors: Paradza, Masimba Wellington
- Date: 2009
- Subjects: Neural networks (Computer science) , Ionosphere , F region
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5460 , http://hdl.handle.net/10962/d1005245 , Neural networks (Computer science) , Ionosphere , F region
- Description: Spread F is a phenomenon of the ionosphere in which the pulses returned from the ionosphere are of a much greater duration than the transmitted ones. The occurrence of spread F can be predicted using the technique of Neural Networks (NNs). This thesis presents the development and evaluation of NN based models (two single station models and a regional model) for predicting the occurrence of spread F over selected stations within the Brazilian sector. The input space for the NNs included the day number (seasonal variation), hour (diurnal variation), sunspot number (measure of the solar activity), magnetic index (measure of the magnetic activity) and magnetic position (latitude, magnetic declination and inclination). Twelve years of spread F data measured during 1978 to 1989 inclusively at the equatorial site Fortaleza and low latitude site Cachoeira Paulista are used in the development of an input space and NN architecture for the NN models. Spread F data that is believed to be related to plasma bubble developments (range spread F) were used in the development of the models while those associated with narrow spectrum irregularities that occur near the F layer (frequency spread F) were excluded. The results of the models show the dependency of the probability of spread F as a function of local time, season and latitude. The models also illustrate some characteristics of spread F such as the onset and peak occurrence of spread F as a function of distance from the equator. Results from these models are presented in this thesis and compared to measured data and to modelled data obtained with an empirical model developed for the same purpose.
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Discourses around abortion in a low-income community in the Western Cape
- Authors: Bowes, Tanya-Ann
- Date: 2009
- Subjects: Abortion -- Moral and ethical aspects , Abortion -- Religious aspects -- Christianity , Patriarchy -- South Africa , Abortion -- South Africa -- Western Cape , Male domination (Social structure)
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: vital:2939 , http://hdl.handle.net/10962/d1002448
- Description: Since the introduction of the Choice on Termination of Pregnancy Act in 1996, research concerning abortion has primarily focused on public health issues or on the personal experience of women. The cultural and social context within which women experience a termination of pregnancy and in which services are offered has received less attention. The purpose of this study was to analyse public discourses around abortion in a low-income community in the Western Cape. Focus groups were used to gather data from three women’s and three men’s groups. The findings suggest that the agenda of pro-life discourses in this community is not always to defend the life of the fetus. Rather these discourses serve to protect, preserve and maintain the power of the traditional nuclear family, headed by the husband, over women’s reproduction and sexuality. Religious and moral arguments serve to disguise the gender issues at stake. However, instances also occurred where TOP was supported if the husband participated in the decision-making process. Therefore, his presence normalised abortion. Thus, the prevailing public discourses around abortion in this community either support or negate abortion in order to further the agenda of patriarchy.
- Full Text:
- Authors: Bowes, Tanya-Ann
- Date: 2009
- Subjects: Abortion -- Moral and ethical aspects , Abortion -- Religious aspects -- Christianity , Patriarchy -- South Africa , Abortion -- South Africa -- Western Cape , Male domination (Social structure)
- Language: English
- Type: text , Thesis , Masters , MSocSci
- Identifier: vital:2939 , http://hdl.handle.net/10962/d1002448
- Description: Since the introduction of the Choice on Termination of Pregnancy Act in 1996, research concerning abortion has primarily focused on public health issues or on the personal experience of women. The cultural and social context within which women experience a termination of pregnancy and in which services are offered has received less attention. The purpose of this study was to analyse public discourses around abortion in a low-income community in the Western Cape. Focus groups were used to gather data from three women’s and three men’s groups. The findings suggest that the agenda of pro-life discourses in this community is not always to defend the life of the fetus. Rather these discourses serve to protect, preserve and maintain the power of the traditional nuclear family, headed by the husband, over women’s reproduction and sexuality. Religious and moral arguments serve to disguise the gender issues at stake. However, instances also occurred where TOP was supported if the husband participated in the decision-making process. Therefore, his presence normalised abortion. Thus, the prevailing public discourses around abortion in this community either support or negate abortion in order to further the agenda of patriarchy.
- Full Text:
Dominant and non-dominant group's perceptions of the government-led economic transformation process in South Africa: report
- Authors: Dlamini, Thobile G. K
- Date: 2009
- Subjects: Group identity -- South Africa Post-apartheid era -- South Africa South Africa -- Ethnic relations Social change -- South Africa South Africa -- Social conditions -- 1994- South Africa -- Economic conditions -- 1991-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2963 , http://hdl.handle.net/10962/d1002472
- Description: The enormous social, economic, and political government-led societal transformation South Africans have experienced over the past 15 years have brought about numerous societal and identity changes. The aim of the present study was to explore how dominant (White participants) and non-dominant (Black participants) groups experiencing the government-led societal transformation process deal with perceptions of intergroup differences based on Social Identity Theory (Tajfel & Turner, 1979, 1986) and related field research. Social Identity Theory predicts that in the presence of intergroup differences group members irrespective of their status position will apply identity management strategies to either improve or maintain their status position. The relationships between perceptions of intergroup relations and identity management strategies as proposed by Social Identity Theory were tested studying 170 second year Rhodes University psychology students. Sixty participants indicated themselves as Black South Africans (representing non-dominant group) and 110 participants identified themselves as White South Africans (dominant group). The results revealed that dominant and non-dominant groups differ systematically regarding the functional interaction between beliefs about the intergroup situation and identity management strategies. The results of the study indicate too, that ingroup identification differentiates between individual and collective strategies irrespective of the group’s status position.
- Full Text:
- Authors: Dlamini, Thobile G. K
- Date: 2009
- Subjects: Group identity -- South Africa Post-apartheid era -- South Africa South Africa -- Ethnic relations Social change -- South Africa South Africa -- Social conditions -- 1994- South Africa -- Economic conditions -- 1991-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2963 , http://hdl.handle.net/10962/d1002472
- Description: The enormous social, economic, and political government-led societal transformation South Africans have experienced over the past 15 years have brought about numerous societal and identity changes. The aim of the present study was to explore how dominant (White participants) and non-dominant (Black participants) groups experiencing the government-led societal transformation process deal with perceptions of intergroup differences based on Social Identity Theory (Tajfel & Turner, 1979, 1986) and related field research. Social Identity Theory predicts that in the presence of intergroup differences group members irrespective of their status position will apply identity management strategies to either improve or maintain their status position. The relationships between perceptions of intergroup relations and identity management strategies as proposed by Social Identity Theory were tested studying 170 second year Rhodes University psychology students. Sixty participants indicated themselves as Black South Africans (representing non-dominant group) and 110 participants identified themselves as White South Africans (dominant group). The results revealed that dominant and non-dominant groups differ systematically regarding the functional interaction between beliefs about the intergroup situation and identity management strategies. The results of the study indicate too, that ingroup identification differentiates between individual and collective strategies irrespective of the group’s status position.
- Full Text:
Dynamics of larval fish and zooplankton in selected south and west coast estuaries of South Africa
- Montoya-Maya, Phanor Hernando
- Authors: Montoya-Maya, Phanor Hernando
- Date: 2009
- Subjects: Marine zooplankton -- South Africa , Zooplankton -- South Africa , Fishes -- Larvae -- South Africa , Estuarine ecology -- South Africa , Estuaries -- South Africa -- Management , Environmental monitoring -- South Africa , Coastal zone management -- South Africa , Estuarine area conservation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5263 , http://hdl.handle.net/10962/d1005107 , Marine zooplankton -- South Africa , Zooplankton -- South Africa , Fishes -- Larvae -- South Africa , Estuarine ecology -- South Africa , Estuaries -- South Africa -- Management , Environmental monitoring -- South Africa , Coastal zone management -- South Africa , Estuarine area conservation -- South Africa
- Description: Larval fish and zooplankton assemblages were studied in nine south and west coast estuaries in the cool-temperate and the cool/warm-temperate boundary region between June 2003 and March 2004. This study served to provide new information on previously unstudied estuaries and expand on existing knowledge of larval fish and zooplankton assemblages associated with various estuary types. The south and west coast estuaries sampled in this study showed lower salinities (12.2 - 13.7), lower water temperatures (14.5 - 16.9 °C) and higher turbidities (k = 0.02 - 0.04) in winter and spring while higher salinities (21.7 - 21.8), higher water temperatures (21.7 - 23.1°C) and lower turbidities (k <0.02) were observed in summer and autumn. Mean winter and summer water temperatures in estuaries were lower than those observed in warm-temperate and subtropical systems by other researchers. A total of 49274 larval fishes were caught, comprising 9 orders, 20 families, 29 genera and 47 taxa. The clupeid Gilchristella aestuaria (78.8 %) dominated the larval fish assemblages and occurred in all estuaries. The majority (70 %) of identified species are endemic to southern Africa and 96.4 % of larval fishes caught were estuary-resident species. The zooplankton study yielded a total of 44 taxa, comprising 7 phyla, >20 orders and >35 families. The copepod Pseudodiaptomus hessei dominated (59 %) the zooplankton and occurred in similar densities to those observed in other South African estuaries. Larval fish and zooplankton varied across seasons, peaking simultaneously in summer although zooplankton showed additional density peaks during the closed phase of some estuaries. Both plankton components were more abundant in the oligohaline and mesohaline zones within the estuaries. Freshwater input, estuary type and the biogeography of the area influenced the composition and structure of larval fish and zooplankton assemblages in these estuaries. The findings suggest that the estuaries are functioning as successful breeding areas for the larvae of endemic estuary-resident fish species and that these estuaries have to be managed to ensure an adequate freshwater supply to maintain the biological integrity of the ecosystem, specially the maintenance of the highly productive River-Estuary Interface (REI) regions.
- Full Text:
- Authors: Montoya-Maya, Phanor Hernando
- Date: 2009
- Subjects: Marine zooplankton -- South Africa , Zooplankton -- South Africa , Fishes -- Larvae -- South Africa , Estuarine ecology -- South Africa , Estuaries -- South Africa -- Management , Environmental monitoring -- South Africa , Coastal zone management -- South Africa , Estuarine area conservation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5263 , http://hdl.handle.net/10962/d1005107 , Marine zooplankton -- South Africa , Zooplankton -- South Africa , Fishes -- Larvae -- South Africa , Estuarine ecology -- South Africa , Estuaries -- South Africa -- Management , Environmental monitoring -- South Africa , Coastal zone management -- South Africa , Estuarine area conservation -- South Africa
- Description: Larval fish and zooplankton assemblages were studied in nine south and west coast estuaries in the cool-temperate and the cool/warm-temperate boundary region between June 2003 and March 2004. This study served to provide new information on previously unstudied estuaries and expand on existing knowledge of larval fish and zooplankton assemblages associated with various estuary types. The south and west coast estuaries sampled in this study showed lower salinities (12.2 - 13.7), lower water temperatures (14.5 - 16.9 °C) and higher turbidities (k = 0.02 - 0.04) in winter and spring while higher salinities (21.7 - 21.8), higher water temperatures (21.7 - 23.1°C) and lower turbidities (k <0.02) were observed in summer and autumn. Mean winter and summer water temperatures in estuaries were lower than those observed in warm-temperate and subtropical systems by other researchers. A total of 49274 larval fishes were caught, comprising 9 orders, 20 families, 29 genera and 47 taxa. The clupeid Gilchristella aestuaria (78.8 %) dominated the larval fish assemblages and occurred in all estuaries. The majority (70 %) of identified species are endemic to southern Africa and 96.4 % of larval fishes caught were estuary-resident species. The zooplankton study yielded a total of 44 taxa, comprising 7 phyla, >20 orders and >35 families. The copepod Pseudodiaptomus hessei dominated (59 %) the zooplankton and occurred in similar densities to those observed in other South African estuaries. Larval fish and zooplankton varied across seasons, peaking simultaneously in summer although zooplankton showed additional density peaks during the closed phase of some estuaries. Both plankton components were more abundant in the oligohaline and mesohaline zones within the estuaries. Freshwater input, estuary type and the biogeography of the area influenced the composition and structure of larval fish and zooplankton assemblages in these estuaries. The findings suggest that the estuaries are functioning as successful breeding areas for the larvae of endemic estuary-resident fish species and that these estuaries have to be managed to ensure an adequate freshwater supply to maintain the biological integrity of the ecosystem, specially the maintenance of the highly productive River-Estuary Interface (REI) regions.
- Full Text:
Economic diversification of a mining town: a case study of Oranjemund
- Authors: Helmuth, Angelo
- Date: 2009
- Subjects: Economic development -- Namibia -- Oranjemund -- Case studies Mineral industries -- Namibia -- Oranjemund -- Case studies Sustainable development -- Namibia -- Oranjemund
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:723 , http://hdl.handle.net/10962/d1003843
- Description: Can mining industries and mining based localities promote Local Economic Development (LED)? This case study, on the mining town of Oranjemund, seeks to examine the economic diversification prospects of the town. Stakeholder views are considered and their aspirations determined, through an interview process. Relevant theories on economic development, growth and sustainability are outline. Lessons are drawn from local and international empirical studies on mining towns. The roles and contributions stakeholders and institutions could realize that could lead to local economic diversification and LED are defined. The opportunities and threats that could affect the town’s LED process are identified. This paper concludes that it is imperative that sound relationships be developed amongst key stakeholders. It further, recommends that a strategic LED plan be designed for Oranjemund and that national government, through the regional and local authority, lead the process.
- Full Text:
- Authors: Helmuth, Angelo
- Date: 2009
- Subjects: Economic development -- Namibia -- Oranjemund -- Case studies Mineral industries -- Namibia -- Oranjemund -- Case studies Sustainable development -- Namibia -- Oranjemund
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:723 , http://hdl.handle.net/10962/d1003843
- Description: Can mining industries and mining based localities promote Local Economic Development (LED)? This case study, on the mining town of Oranjemund, seeks to examine the economic diversification prospects of the town. Stakeholder views are considered and their aspirations determined, through an interview process. Relevant theories on economic development, growth and sustainability are outline. Lessons are drawn from local and international empirical studies on mining towns. The roles and contributions stakeholders and institutions could realize that could lead to local economic diversification and LED are defined. The opportunities and threats that could affect the town’s LED process are identified. This paper concludes that it is imperative that sound relationships be developed amongst key stakeholders. It further, recommends that a strategic LED plan be designed for Oranjemund and that national government, through the regional and local authority, lead the process.
- Full Text:
Economic responsiveness in organisational psychology curricula
- Authors: Van Niekerk, Roelf
- Date: 2009
- Subjects: Psychology, Industrial -- Study and teaching (Higher) -- South Africa Universities and colleges -- Curricula -- South Africa College graduates -- Employment -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1319 , http://hdl.handle.net/10962/d1003952
- Description: This study focused on a topic at the intersection of two contexts, namely curriculum responsiveness and industrial/organisational psychology (IOP). The rationale for this study is based on two considerations. Firstly, a review of the IOP curricula offered at ten prominent South African universities revealed little overlap. This suggests that academic departments are not guided by shared principles when they implement decisions about the content or sequencing of curriculum content. Secondly, the Department of Education urges academics to design curricula that are relevant and responsive to contemporary conditions. These two considerations motivated the investigation of the following research question: What key performance areas (KPAs) do employers specify when they advertise positions suitable for IOP graduates? The investigation had two aims, namely (a) to systematically analyse the KPAs specified in job advertisements and (b) to compile KPA templates that may be used by IOP departments who wish to revise or transform their curricula. The research design of this study has five characteristics, namely that it is: (a) qualitative, (b) naturalistic, (c), descriptive, (d) applied, and (e) strategic. The study employed a purposive sampling strategy that involved the collection of documentary data (job advertisements aimed at recruiting IOP graduates) over a 52-week period (N=1115). The data was content analysed by means of a six-step documentary analysis method. Specific strategies were employed to enhance the validity of the findings. These strategies focused on credibility, transferability, dependability, and confirmability. Similarly, the ethical standing of the investigation was promoted by addressing four considerations, namely autonomy and respect for dignity, non-maleficence, beneficence, and justice. The data analysis procedure produced comprehensive and detailed qualitative descriptions of (a) 21 occupational categories, (b) 4070 KPA themes and (c) 84 KPA clusters. In addition, the number of occupational categories, KPA themes and KPA clusters were recorded and interpreted. In addition, the data analysis procedure produced comprehensive KPA templates that IOP departments may find useful. The templates reflect the KPAs specified by advertisements aimed at recruiting IOP graduates for a range of occupational categories and were designed to be used as benchmarks against which the economic responsiveness of curricula can be compared.
- Full Text:
- Authors: Van Niekerk, Roelf
- Date: 2009
- Subjects: Psychology, Industrial -- Study and teaching (Higher) -- South Africa Universities and colleges -- Curricula -- South Africa College graduates -- Employment -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1319 , http://hdl.handle.net/10962/d1003952
- Description: This study focused on a topic at the intersection of two contexts, namely curriculum responsiveness and industrial/organisational psychology (IOP). The rationale for this study is based on two considerations. Firstly, a review of the IOP curricula offered at ten prominent South African universities revealed little overlap. This suggests that academic departments are not guided by shared principles when they implement decisions about the content or sequencing of curriculum content. Secondly, the Department of Education urges academics to design curricula that are relevant and responsive to contemporary conditions. These two considerations motivated the investigation of the following research question: What key performance areas (KPAs) do employers specify when they advertise positions suitable for IOP graduates? The investigation had two aims, namely (a) to systematically analyse the KPAs specified in job advertisements and (b) to compile KPA templates that may be used by IOP departments who wish to revise or transform their curricula. The research design of this study has five characteristics, namely that it is: (a) qualitative, (b) naturalistic, (c), descriptive, (d) applied, and (e) strategic. The study employed a purposive sampling strategy that involved the collection of documentary data (job advertisements aimed at recruiting IOP graduates) over a 52-week period (N=1115). The data was content analysed by means of a six-step documentary analysis method. Specific strategies were employed to enhance the validity of the findings. These strategies focused on credibility, transferability, dependability, and confirmability. Similarly, the ethical standing of the investigation was promoted by addressing four considerations, namely autonomy and respect for dignity, non-maleficence, beneficence, and justice. The data analysis procedure produced comprehensive and detailed qualitative descriptions of (a) 21 occupational categories, (b) 4070 KPA themes and (c) 84 KPA clusters. In addition, the number of occupational categories, KPA themes and KPA clusters were recorded and interpreted. In addition, the data analysis procedure produced comprehensive KPA templates that IOP departments may find useful. The templates reflect the KPAs specified by advertisements aimed at recruiting IOP graduates for a range of occupational categories and were designed to be used as benchmarks against which the economic responsiveness of curricula can be compared.
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Electrochemical studies of titanium, manganese and cobalt phthalocyanines
- Authors: Nombona, Nolwazi
- Date: 2009
- Subjects: Titanium , Manganese , Cobalt , Phthalocyanines , Electrochemistry , Electrodes , Self-assembly (Chemistry)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4312 , http://hdl.handle.net/10962/d1004970 , Titanium , Manganese , Cobalt , Phthalocyanines , Electrochemistry , Electrodes , Self-assembly (Chemistry)
- Description: Syntheses, spectral, electrochemical and spectroelectrochemical studies of phenylthio and amino derivatised metallophthalocyanines complexes are reported. The complexes are immobilized onto a gold macro disk, gold ultramicroelectrode and gold coated fiber electrodes via self assembly with phenylthio MPc derivatives or onto a glassy carbon electrode via electropolymerisation with amino MPc derivatives. For the first time MPc SAMs were formed on gold coated fiber. The electrocatalytic behavior of the modified electrodes was studied for the detection of nitrite and L-cysteine, all modified electrodes showed improved electrocatalytic oxidation compared to the unmodified electrode. The MPc complexes catalyzed nitrite oxidation via a two-electron mechanism producing nitrate. Cobalt tetraaminophthalocyanine showed the best catalytic activity for nitrite oxidation in terms of overpotential lowering compared to other complexes and thus was used for nitrite detection in a food sample, the nitrite concentration was determined to be 59.13 ppm, well within the limit for cured meat products. Electrocatalytic oxidation of L-cysteine on SAM modified gold coated fiber was reported for the first time. The gold coated fiber and ultamicro cylinder electrode were less stable towards the electro-oxidation of cysteine compared to its oxidation on the gold disk. The gold disk electrode gave better catalytic performance in terms of stability and reduction of overpotential. The phenylthio cobalt phthalocyanine derivative gave the best catalytic activity for L-cysteine oxidation in terms of overpotential lowering compared to other phenylthio derivatized MPc complexes. The amount of L-cysteine in human urine was 2.4 mM, well within the urinary L-cysteine excretion range for a healthy human being.
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- Authors: Nombona, Nolwazi
- Date: 2009
- Subjects: Titanium , Manganese , Cobalt , Phthalocyanines , Electrochemistry , Electrodes , Self-assembly (Chemistry)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4312 , http://hdl.handle.net/10962/d1004970 , Titanium , Manganese , Cobalt , Phthalocyanines , Electrochemistry , Electrodes , Self-assembly (Chemistry)
- Description: Syntheses, spectral, electrochemical and spectroelectrochemical studies of phenylthio and amino derivatised metallophthalocyanines complexes are reported. The complexes are immobilized onto a gold macro disk, gold ultramicroelectrode and gold coated fiber electrodes via self assembly with phenylthio MPc derivatives or onto a glassy carbon electrode via electropolymerisation with amino MPc derivatives. For the first time MPc SAMs were formed on gold coated fiber. The electrocatalytic behavior of the modified electrodes was studied for the detection of nitrite and L-cysteine, all modified electrodes showed improved electrocatalytic oxidation compared to the unmodified electrode. The MPc complexes catalyzed nitrite oxidation via a two-electron mechanism producing nitrate. Cobalt tetraaminophthalocyanine showed the best catalytic activity for nitrite oxidation in terms of overpotential lowering compared to other complexes and thus was used for nitrite detection in a food sample, the nitrite concentration was determined to be 59.13 ppm, well within the limit for cured meat products. Electrocatalytic oxidation of L-cysteine on SAM modified gold coated fiber was reported for the first time. The gold coated fiber and ultamicro cylinder electrode were less stable towards the electro-oxidation of cysteine compared to its oxidation on the gold disk. The gold disk electrode gave better catalytic performance in terms of stability and reduction of overpotential. The phenylthio cobalt phthalocyanine derivative gave the best catalytic activity for L-cysteine oxidation in terms of overpotential lowering compared to other phenylthio derivatized MPc complexes. The amount of L-cysteine in human urine was 2.4 mM, well within the urinary L-cysteine excretion range for a healthy human being.
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Enhancing learner centred education through the eco-schools framework: case studies of eco-schools practice in South Africa and Namibia
- Authors: Haingura, Rudolph
- Date: 2009
- Subjects: Education -- South Africa -- Case studies Education -- Namibia -- Case studies Educational change -- South Africa -- Case studies Educational change -- Namibia -- Case studies Teachers -- Training of -- South Africa -- Case studies Teachers -- Training of -- Namibia -- Case studies Environmental education -- South Africa -- Case studies Environmental education -- Namibia -- Case studies School improvement programs
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1509 , http://hdl.handle.net/10962/d1003391
- Description: Since the early 1990’s both South Africa and Namibia have been engaged in educational reform processes to address the discriminatory impacts and orientations of education under Bantu Education which were implemented in both countries prior to independence (Namibia in 1990, and South Africa in 1994). A feature of both educational reform processes is the underpinning theory of learning which draws on social constructivism, and which is articulated as learner centred education. This approach to teaching and learning infuses both policy frameworks. Another common feature is the introduction of environmental education into the formal education systems of both countries, a process which has been championed by development assistance, and which has been supported by programmes such as the Eco-Schools programme which is an international environmental education initiative started after the Rio Earth Summit in 1992, and implemented in a number of countries, including South Africa. The programme has also been piloted in some schools in Namibia. To date no research has been done on the way in which the Eco-Schools framework (its practices, organizing principles, evaluation processes etc.) enhance learner centred education. This study therefore aimed to investigate and understand how the Eco-Schools framework can enhance learner centred education. The study was conducted in 2007 in three Eco-Schools in Namibia and four Eco-Schools in South Africa in the context of the broader national programmes of implementing learner centred education policies, and environmental education histories. The study used a case study methodology, using observation, interviews, and document analysis as the main methods for data generation. The analytical process followed two stages: the first involved an inductive analysis using categories which were organized into a series of analytical memos. The second phase of data analysis involved recontextualising the data drawing on theory and contextual insights to provide insights that address the research question, using analytical statements. The main findings of the study are that the Eco-Schools framework provides numerous opportunities to enhance learner centred education, through contextualization of learning, through strengthening school-community interactions, and through enabling active involvement of learners in decision making and a range of contextually meaningful Eco-Schools practices. The study also showed that the Eco-Schools framework allows for empowerment of learners in relation to diverse needs, and also allows for learner initiated contributions, although this aspect was not well developed in the schools that were included in this study. The study also found that the benefits of Eco-Schools in terms of enhancing learner centred education were limited to only a few learners who were involved in club activities or who were being taught by enthusiastic teachers who were participating in the Eco-Schools programme. The study showed that these benefits can be more widely shared if more teachers were to get involved, and if the Eco-Schools programme were better understood in relation to the curriculum requirements of various subjects and learning areas, and if the Eco-Schools practices could be more successfully integrated across the curriculum. The study also showed that various forms of support were required for implementing the Eco-Schools programme, most notably the support of the Principal, and the Department of Education. The study also identified that parents and other stakeholders in the school were supportive of the Eco-Schools programme since it was perceived to have relevance to learning, as well as the community. The results broadly confirmed that the implementation of Eco-Schools using a whole school, values based and active learning approach promotes a school culture which enhances learner centred education more broadly across the school. The study also found that the Eco-Schools programme added a new dimension to existing discourses on learner centred education, which could be described as a community linked or situated approach to learner centred education.
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- Authors: Haingura, Rudolph
- Date: 2009
- Subjects: Education -- South Africa -- Case studies Education -- Namibia -- Case studies Educational change -- South Africa -- Case studies Educational change -- Namibia -- Case studies Teachers -- Training of -- South Africa -- Case studies Teachers -- Training of -- Namibia -- Case studies Environmental education -- South Africa -- Case studies Environmental education -- Namibia -- Case studies School improvement programs
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1509 , http://hdl.handle.net/10962/d1003391
- Description: Since the early 1990’s both South Africa and Namibia have been engaged in educational reform processes to address the discriminatory impacts and orientations of education under Bantu Education which were implemented in both countries prior to independence (Namibia in 1990, and South Africa in 1994). A feature of both educational reform processes is the underpinning theory of learning which draws on social constructivism, and which is articulated as learner centred education. This approach to teaching and learning infuses both policy frameworks. Another common feature is the introduction of environmental education into the formal education systems of both countries, a process which has been championed by development assistance, and which has been supported by programmes such as the Eco-Schools programme which is an international environmental education initiative started after the Rio Earth Summit in 1992, and implemented in a number of countries, including South Africa. The programme has also been piloted in some schools in Namibia. To date no research has been done on the way in which the Eco-Schools framework (its practices, organizing principles, evaluation processes etc.) enhance learner centred education. This study therefore aimed to investigate and understand how the Eco-Schools framework can enhance learner centred education. The study was conducted in 2007 in three Eco-Schools in Namibia and four Eco-Schools in South Africa in the context of the broader national programmes of implementing learner centred education policies, and environmental education histories. The study used a case study methodology, using observation, interviews, and document analysis as the main methods for data generation. The analytical process followed two stages: the first involved an inductive analysis using categories which were organized into a series of analytical memos. The second phase of data analysis involved recontextualising the data drawing on theory and contextual insights to provide insights that address the research question, using analytical statements. The main findings of the study are that the Eco-Schools framework provides numerous opportunities to enhance learner centred education, through contextualization of learning, through strengthening school-community interactions, and through enabling active involvement of learners in decision making and a range of contextually meaningful Eco-Schools practices. The study also showed that the Eco-Schools framework allows for empowerment of learners in relation to diverse needs, and also allows for learner initiated contributions, although this aspect was not well developed in the schools that were included in this study. The study also found that the benefits of Eco-Schools in terms of enhancing learner centred education were limited to only a few learners who were involved in club activities or who were being taught by enthusiastic teachers who were participating in the Eco-Schools programme. The study showed that these benefits can be more widely shared if more teachers were to get involved, and if the Eco-Schools programme were better understood in relation to the curriculum requirements of various subjects and learning areas, and if the Eco-Schools practices could be more successfully integrated across the curriculum. The study also showed that various forms of support were required for implementing the Eco-Schools programme, most notably the support of the Principal, and the Department of Education. The study also identified that parents and other stakeholders in the school were supportive of the Eco-Schools programme since it was perceived to have relevance to learning, as well as the community. The results broadly confirmed that the implementation of Eco-Schools using a whole school, values based and active learning approach promotes a school culture which enhances learner centred education more broadly across the school. The study also found that the Eco-Schools programme added a new dimension to existing discourses on learner centred education, which could be described as a community linked or situated approach to learner centred education.
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