Challenges in topside ionospheric modelling over South Africa
- Authors: Sibanda, Patrick
- Date: 2010
- Subjects: Ionospheric electron density -- South Africa Neural networks (Computer science) Atmosphere, Upper Ionosphere
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5453 , http://hdl.handle.net/10962/d1005238
- Description: This thesis creates a basic framework and provides the information necessary to create a more accurate description of the topside ionosphere in terms of the altitude variation of the electron density (Ne) over the South African region. The detailed overview of various topside ionospheric modelling techniques, with specific emphasis on their implications for the efforts to model the South African topside, provides a starting point towards achieving the goals. The novelty of the thesis lies in the investigation of the applicabilityof three different techniques to model the South African topside ionosphere: (1) The possibility of using Artificial Neural Network (ANN) techniques for empirical modelling of the topside ionosphere based on the available, however irregularly sampled, topside sounder measurements. The goal of this model was to test the ability of ANN techniques to capture the complex relationships between the various ionospheric variables using irregularly distributed measurements. While this technique is promising, the method did not show significant improvement over the International Reference Ionosphere (IRI) model results when compared with the actual measurements. (2) Application of the diffusive equilibrium theory. Although based on sound physics foundations, the method only operates on a generalised level leading to results that are not necessarily unique. Furthermore, the approach relies on many ionospheric variables as inputs which are derived from other models whose accuracy is not verified. (3) Attempts to complement the standard functional techniques, (Chapman, Epstein, Exponential and Parabolic), with Global Positioning System (GPS) and ionosonde measurements in an effort to provide deeper insights into the actual conditions within the ionosphere. The vertical Ne distribution is reconstructed by linking together the different aspects of the constituent ions and their transition height by considering how they influence the shape of the profile. While this approach has not been tested against actual measurements, results show that the method could be potentially useful for topside ionospheric studies. Due to the limitations of each technique reviewed, this thesis observes that the employment of an approach that incorporates both theoretical onsiderations and empirical aspects has the potential to lead to a more accurate characterisation of the topside ionospheric behaviour, and resulting in improved models in terms of reliability and forecasting ability. The point is made that a topside sounder mission for South Africa would provide the required measured topside ionospheric data and answer the many science questions that this region poses as well as solving a number of the limitations set out in this thesis.
- Full Text:
- Authors: Sibanda, Patrick
- Date: 2010
- Subjects: Ionospheric electron density -- South Africa Neural networks (Computer science) Atmosphere, Upper Ionosphere
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5453 , http://hdl.handle.net/10962/d1005238
- Description: This thesis creates a basic framework and provides the information necessary to create a more accurate description of the topside ionosphere in terms of the altitude variation of the electron density (Ne) over the South African region. The detailed overview of various topside ionospheric modelling techniques, with specific emphasis on their implications for the efforts to model the South African topside, provides a starting point towards achieving the goals. The novelty of the thesis lies in the investigation of the applicabilityof three different techniques to model the South African topside ionosphere: (1) The possibility of using Artificial Neural Network (ANN) techniques for empirical modelling of the topside ionosphere based on the available, however irregularly sampled, topside sounder measurements. The goal of this model was to test the ability of ANN techniques to capture the complex relationships between the various ionospheric variables using irregularly distributed measurements. While this technique is promising, the method did not show significant improvement over the International Reference Ionosphere (IRI) model results when compared with the actual measurements. (2) Application of the diffusive equilibrium theory. Although based on sound physics foundations, the method only operates on a generalised level leading to results that are not necessarily unique. Furthermore, the approach relies on many ionospheric variables as inputs which are derived from other models whose accuracy is not verified. (3) Attempts to complement the standard functional techniques, (Chapman, Epstein, Exponential and Parabolic), with Global Positioning System (GPS) and ionosonde measurements in an effort to provide deeper insights into the actual conditions within the ionosphere. The vertical Ne distribution is reconstructed by linking together the different aspects of the constituent ions and their transition height by considering how they influence the shape of the profile. While this approach has not been tested against actual measurements, results show that the method could be potentially useful for topside ionospheric studies. Due to the limitations of each technique reviewed, this thesis observes that the employment of an approach that incorporates both theoretical onsiderations and empirical aspects has the potential to lead to a more accurate characterisation of the topside ionospheric behaviour, and resulting in improved models in terms of reliability and forecasting ability. The point is made that a topside sounder mission for South Africa would provide the required measured topside ionospheric data and answer the many science questions that this region poses as well as solving a number of the limitations set out in this thesis.
- Full Text:
Democratic leadership and management practices in a rural Namibian secondary school
- Authors: Mabuku, Robert Nalisa
- Date: 2010
- Subjects: Educational leadership -- Namibia -- Case studies School management and organization -- Namibia -- Case studies Education, Secondary -- Namibia -- Case studies Educational change -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1489 , http://hdl.handle.net/10962/d1003370
- Description: The primary purpose of this research was to investigate the understanding and implementation of democratic leadership and management in schools by school managers and other members of the school community in leadership and management roles as advocated by the policy of Education for all. The study also aimed at identifying any gaps in the understanding and practice of the participants in order to enhance democratic leadership and management in schools. Qualitative research using the interpretive approach was the methodology employed in order to fulfill the intention of the study, namely to investigate the participants` experiences and understanding of democratic education leadership and management. The case study method was appropriate to understand the meanings the participants attached to their practice in their natural setting. Data were collected by using semi-structured interviews, document analysis, and observation. The sample for the study consisted of ten participants: the principal, the head of department, two School Board members, two senior teachers, two Learner Representative Council members and two class captains. The findings suggest that the participants understood and practised democratic ELM in terms of broader participation, open communication, delegation for empowerment, learning organisation, shared decision-making, shared leadership and teamwork. However, the data suggest areas of concern in the participants` understanding and implementation of the policy which could be strengthened to entrench the policy. The study recommends that education policy makers, education managers, school managers, teachers, parents and learners all work towards improving democratic ELM in schools. In order to achieve this objective, policy makers are urged to avoid ambiguity to enable all implementers to fully understand policies. Education managers could ensure school-wide training on the policy while school managers and other stakeholders should engage in self-reflection and introspection and be more proactive towards improving their own understanding and practice.
- Full Text:
- Authors: Mabuku, Robert Nalisa
- Date: 2010
- Subjects: Educational leadership -- Namibia -- Case studies School management and organization -- Namibia -- Case studies Education, Secondary -- Namibia -- Case studies Educational change -- Namibia -- Case studies
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1489 , http://hdl.handle.net/10962/d1003370
- Description: The primary purpose of this research was to investigate the understanding and implementation of democratic leadership and management in schools by school managers and other members of the school community in leadership and management roles as advocated by the policy of Education for all. The study also aimed at identifying any gaps in the understanding and practice of the participants in order to enhance democratic leadership and management in schools. Qualitative research using the interpretive approach was the methodology employed in order to fulfill the intention of the study, namely to investigate the participants` experiences and understanding of democratic education leadership and management. The case study method was appropriate to understand the meanings the participants attached to their practice in their natural setting. Data were collected by using semi-structured interviews, document analysis, and observation. The sample for the study consisted of ten participants: the principal, the head of department, two School Board members, two senior teachers, two Learner Representative Council members and two class captains. The findings suggest that the participants understood and practised democratic ELM in terms of broader participation, open communication, delegation for empowerment, learning organisation, shared decision-making, shared leadership and teamwork. However, the data suggest areas of concern in the participants` understanding and implementation of the policy which could be strengthened to entrench the policy. The study recommends that education policy makers, education managers, school managers, teachers, parents and learners all work towards improving democratic ELM in schools. In order to achieve this objective, policy makers are urged to avoid ambiguity to enable all implementers to fully understand policies. Education managers could ensure school-wide training on the policy while school managers and other stakeholders should engage in self-reflection and introspection and be more proactive towards improving their own understanding and practice.
- Full Text:
Participatory human development in post-apartheid South Africa: a discussion of the 2006/7 Tantyi Youth Empowerment Project
- Authors: Kulundu, Injairu M
- Date: 2010
- Subjects: Spirals Trust (South Africa) Community development -- South Africa -- Citizen participation Economic development projects -- South Africa -- Citizen participation Youth in development -- South Africa Non-governmental organizations -- South Africa Post-apartheid era -- South Africa South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2791 , http://hdl.handle.net/10962/d1003001
- Description: This thesis relates the work of a non-governmental organisation, The Spirals Trust, to discussions on human and participatory development. The focus of the study is one of The Spirals Trust’s projects, the 2006/7 Tantyi Youth Empowerment Project, which is discussed in relation to theoretical material on human development and participatory development. Collectively these perspectives are defined in this thesis as ‘participatory human development’. The 2006/7 Tantyi Youth Empowerment Project illustrates some of the challenges that face the practice of participatory human development. Workshops and focus group interviews were conducted with participants who were part of the 2006/7 Tantyi Youth Empowerment Project in order to draw out their experiences of the project. Questions were created from themes that emerged from the participants’ discussion of their experiences and these questions were then posed to members of staff of The Spirals Trust. The experiences of both the participants and the staff members are discussed in order to explore issues that emerge in the practice of participatory human development in the 2006/7 Tantyi Youth Empowerment Project. The results highlight the challenges of putting into action the tenets of participatory human development. Feedback showed that a focus on personal development can help cultivate the ethic of participation. The effort that this entailed on the part of facilitators is discussed. The importance of exposing and continually working with power dynamics that may emerge in projects of this nature is revealed and the eroding influence of bureaucratic compliance in projects like this one is explored. The study also suggests that there is a need to promote development initiatives that challenge the political status quo rather than just finding ways to incorporate the marginalised more effectively into current systems. New questions that the research poses to the practice of participatory human development are considered in conjunction with suggestions for further research.
- Full Text:
- Authors: Kulundu, Injairu M
- Date: 2010
- Subjects: Spirals Trust (South Africa) Community development -- South Africa -- Citizen participation Economic development projects -- South Africa -- Citizen participation Youth in development -- South Africa Non-governmental organizations -- South Africa Post-apartheid era -- South Africa South Africa -- Politics and government -- 1994-
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2791 , http://hdl.handle.net/10962/d1003001
- Description: This thesis relates the work of a non-governmental organisation, The Spirals Trust, to discussions on human and participatory development. The focus of the study is one of The Spirals Trust’s projects, the 2006/7 Tantyi Youth Empowerment Project, which is discussed in relation to theoretical material on human development and participatory development. Collectively these perspectives are defined in this thesis as ‘participatory human development’. The 2006/7 Tantyi Youth Empowerment Project illustrates some of the challenges that face the practice of participatory human development. Workshops and focus group interviews were conducted with participants who were part of the 2006/7 Tantyi Youth Empowerment Project in order to draw out their experiences of the project. Questions were created from themes that emerged from the participants’ discussion of their experiences and these questions were then posed to members of staff of The Spirals Trust. The experiences of both the participants and the staff members are discussed in order to explore issues that emerge in the practice of participatory human development in the 2006/7 Tantyi Youth Empowerment Project. The results highlight the challenges of putting into action the tenets of participatory human development. Feedback showed that a focus on personal development can help cultivate the ethic of participation. The effort that this entailed on the part of facilitators is discussed. The importance of exposing and continually working with power dynamics that may emerge in projects of this nature is revealed and the eroding influence of bureaucratic compliance in projects like this one is explored. The study also suggests that there is a need to promote development initiatives that challenge the political status quo rather than just finding ways to incorporate the marginalised more effectively into current systems. New questions that the research poses to the practice of participatory human development are considered in conjunction with suggestions for further research.
- Full Text:
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