Desert
- Authors: Harper, Sean Julian
- Date: 2000
- Subjects: Rawls, John, 1921-2002 , Rawls, John, 1921-2002 Theory of justice , Ethics
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2710 , http://hdl.handle.net/10962/d1002840 , Rawls, John, 1921-2002 , Rawls, John, 1921-2002 Theory of justice , Ethics
- Description: This thesis examines the idea of desert as expounded in the work of John Rawls, and some of the implications of this conception of desert for moral and political philosophy. In this work, I analyse a series of arguments against retaining this particular conception of desert.I argue that none of these arguments sufficiently diminishes the force of Rawls’ argument for desert, while many of them do state, and I argue that they are correct in doing so, that this conception of desert is dangerous for political or moral philosophy to maintain. I argue that the moral, political and legal implications of accepting this account of desert severely undermine various institutions of differential treatment, and indeed, moral assessment. I regard it as obvious that societies must, on occasion, treat members of those societies differently, for moral, as well as practical reasons. The Rawlsian account of desert, and the account of responsibility on which it rests, however, will endanger the legitimacy of such procedures. I argue further that the Rawlsian account of desert requires that differences in wealth, and inheritance of wealth, influence and privilege be diminished, if not abolished, if we are to talk of any form of desert meaningfully. I argue that this is a strength of Rawls’ account, and further that any account of desert that is true to the philosophical tradition of the concept will require similar steps to be taken. The primary aim of this thesis is to show that Rawls’ arguments against desert are serious ones, both in terms of strength and scope, and that they must be addressed. I intend to show that these arguments are founded on strong moral intuitions, and that it is plausible that these intuitions may need revision. Finally,I intend to show that desert is an important moral and political concept, and that the disciplines of moral and political philosophy will be impoverished by the absence this concept. This absence, I will argue, is a natural consequence of the acceptance of the Rawlsian arguments.
- Full Text:
- Date Issued: 2000
- Authors: Harper, Sean Julian
- Date: 2000
- Subjects: Rawls, John, 1921-2002 , Rawls, John, 1921-2002 Theory of justice , Ethics
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2710 , http://hdl.handle.net/10962/d1002840 , Rawls, John, 1921-2002 , Rawls, John, 1921-2002 Theory of justice , Ethics
- Description: This thesis examines the idea of desert as expounded in the work of John Rawls, and some of the implications of this conception of desert for moral and political philosophy. In this work, I analyse a series of arguments against retaining this particular conception of desert.I argue that none of these arguments sufficiently diminishes the force of Rawls’ argument for desert, while many of them do state, and I argue that they are correct in doing so, that this conception of desert is dangerous for political or moral philosophy to maintain. I argue that the moral, political and legal implications of accepting this account of desert severely undermine various institutions of differential treatment, and indeed, moral assessment. I regard it as obvious that societies must, on occasion, treat members of those societies differently, for moral, as well as practical reasons. The Rawlsian account of desert, and the account of responsibility on which it rests, however, will endanger the legitimacy of such procedures. I argue further that the Rawlsian account of desert requires that differences in wealth, and inheritance of wealth, influence and privilege be diminished, if not abolished, if we are to talk of any form of desert meaningfully. I argue that this is a strength of Rawls’ account, and further that any account of desert that is true to the philosophical tradition of the concept will require similar steps to be taken. The primary aim of this thesis is to show that Rawls’ arguments against desert are serious ones, both in terms of strength and scope, and that they must be addressed. I intend to show that these arguments are founded on strong moral intuitions, and that it is plausible that these intuitions may need revision. Finally,I intend to show that desert is an important moral and political concept, and that the disciplines of moral and political philosophy will be impoverished by the absence this concept. This absence, I will argue, is a natural consequence of the acceptance of the Rawlsian arguments.
- Full Text:
- Date Issued: 2000
Designing and implementing a virtual reality interaction framework
- Authors: Rorke, Michael
- Date: 2000
- Subjects: Virtual reality , Computer simulation , Human-computer interaction , Computer graphics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4623 , http://hdl.handle.net/10962/d1006491 , Virtual reality , Computer simulation , Human-computer interaction , Computer graphics
- Description: Virtual Reality offers the possibility for humans to interact in a more natural way with the computer and its applications. Currently, Virtual Reality is used mainly in the field of visualisation where 3D graphics allow users to more easily view complex sets of data or structures. The field of interaction in Virtual Reality has been largely neglected due mainly to problems with input devices and equipment costs. Recent research has aimed to overcome these interaction problems, thereby creating a usable interaction platform for Virtual Reality. This thesis presents a background into the field of interaction in Virtual Reality. It goes on to propose a generic framework for the implementation of common interaction techniques into a homogeneous application development environment. This framework adds a new layer to the standard Virtual Reality toolkit – the interaction abstraction layer, or interactor layer. This separation is in line with current HCI practices. The interactor layer is further divided into specific sections – input component, interaction component, system component, intermediaries, entities and widgets. Each of these performs a specific function, with clearly defined interfaces between the different components to promote easy objectoriented implementation of the framework. The validity of the framework is shown in comparison with accepted taxonomies in the area of Virtual Reality interaction. Thus demonstrating that the framework covers all the relevant factors involved in the field. Furthermore, the thesis describes an implementation of this framework. The implementation was completed using the Rhodes University CoRgi Virtual Reality toolkit. Several postgraduate students in the Rhodes University Computer Science Department utilised the framework implementation to develop a set of case studies. These case studies demonstrate the practical use of the framework to create useful Virtual Reality applications, as well as demonstrating the generic nature of the framework and its extensibility to be able to handle new interaction techniques. Finally, the generic nature of the framework is further demonstrated by moving it from the standard CoRgi Virtual Reality toolkit, to a distributed version of this toolkit. The distributed implementation of the framework utilises the Common Object Request Broker Architecture (CORBA) to implement the distribution of the objects in the system. Using this distributed implementation, we are able to ascertain that CORBA is useful in the field of distributed real-time Virtual Reality, even taking into account the extra overhead introduced by the additional abstraction layer. We conclude from this thesis that it is important to abstract the interaction layer from the other layers of a Virtual Reality toolkit in order to provide a consistent interface to developers. We have shown that our framework is implementable and useful in the field, making it easier for developers to include interaction in their Virtual Reality applications. Our framework is able to handle all the current aspects of interaction in Virtual Reality, as well as being general enough to implement future interaction techniques. The framework is also applicable to different Virtual Reality toolkits and development platforms, making it ideal for developing general, cross-platform interactive Virtual Reality applications.
- Full Text:
- Date Issued: 2000
- Authors: Rorke, Michael
- Date: 2000
- Subjects: Virtual reality , Computer simulation , Human-computer interaction , Computer graphics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4623 , http://hdl.handle.net/10962/d1006491 , Virtual reality , Computer simulation , Human-computer interaction , Computer graphics
- Description: Virtual Reality offers the possibility for humans to interact in a more natural way with the computer and its applications. Currently, Virtual Reality is used mainly in the field of visualisation where 3D graphics allow users to more easily view complex sets of data or structures. The field of interaction in Virtual Reality has been largely neglected due mainly to problems with input devices and equipment costs. Recent research has aimed to overcome these interaction problems, thereby creating a usable interaction platform for Virtual Reality. This thesis presents a background into the field of interaction in Virtual Reality. It goes on to propose a generic framework for the implementation of common interaction techniques into a homogeneous application development environment. This framework adds a new layer to the standard Virtual Reality toolkit – the interaction abstraction layer, or interactor layer. This separation is in line with current HCI practices. The interactor layer is further divided into specific sections – input component, interaction component, system component, intermediaries, entities and widgets. Each of these performs a specific function, with clearly defined interfaces between the different components to promote easy objectoriented implementation of the framework. The validity of the framework is shown in comparison with accepted taxonomies in the area of Virtual Reality interaction. Thus demonstrating that the framework covers all the relevant factors involved in the field. Furthermore, the thesis describes an implementation of this framework. The implementation was completed using the Rhodes University CoRgi Virtual Reality toolkit. Several postgraduate students in the Rhodes University Computer Science Department utilised the framework implementation to develop a set of case studies. These case studies demonstrate the practical use of the framework to create useful Virtual Reality applications, as well as demonstrating the generic nature of the framework and its extensibility to be able to handle new interaction techniques. Finally, the generic nature of the framework is further demonstrated by moving it from the standard CoRgi Virtual Reality toolkit, to a distributed version of this toolkit. The distributed implementation of the framework utilises the Common Object Request Broker Architecture (CORBA) to implement the distribution of the objects in the system. Using this distributed implementation, we are able to ascertain that CORBA is useful in the field of distributed real-time Virtual Reality, even taking into account the extra overhead introduced by the additional abstraction layer. We conclude from this thesis that it is important to abstract the interaction layer from the other layers of a Virtual Reality toolkit in order to provide a consistent interface to developers. We have shown that our framework is implementable and useful in the field, making it easier for developers to include interaction in their Virtual Reality applications. Our framework is able to handle all the current aspects of interaction in Virtual Reality, as well as being general enough to implement future interaction techniques. The framework is also applicable to different Virtual Reality toolkits and development platforms, making it ideal for developing general, cross-platform interactive Virtual Reality applications.
- Full Text:
- Date Issued: 2000
Designing and making a difference: an exploration of technology education for rural school teachers
- Authors: Schäfer, Marc
- Date: 2000
- Subjects: Technology -- Study and teaching -- South Africa -- Eastern Cape Technology -- Study and teaching -- South Africa Rural schools -- South Africa -- Eastern Cape Education, Rural -- South Africa Winterberg schools trust
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1491 , http://hdl.handle.net/10962/d1003372
- Description: This qualitative study focused on a Technology Education programme for farm school teachers in the Eastern Cape province of South Africa. These teachers were faced with the challenge of incorporating Technology Education into their curriculum. The study was conducted within the context of an investigation into the conceptual nature of technology and an exploration of the theoretical underpinnings of Technology Education within both the international and South African context. Technology Education is being introduced into the South African curriculum against a background of educational transformation and the building of capacity to solve real life problems. This calls for a curriculum that will empower learners to be innovative, creative and skilled problem solvers. The introduction and incorporation of Technoiogy Education into the school curriculum poses a formidable challenge to farm schools in particular. Their unique history of neglect and legacy of underqualified teachers has made the introduction of any curriculum innovation process very difficult and challenging. This study analyses how an introductory Technology Education programme for farm school teachers in the Winterberg area of the Eastern Cape impacted~ on the teachers' professional and personal lives. It shows the importance of developing teclpological skills in conjunction with life skills in cO.ntributing to the empowerment, both in the work place and in the wider context, of rural school teachers. It highlights the need for supportive in-service education programmes and strengthens the argument for an integrative and mulitidisciplinary approach to the introduction of Technology Education in farm schools. Data was collected by means of questionnaires, interviews and photographs.
- Full Text:
- Date Issued: 2000
- Authors: Schäfer, Marc
- Date: 2000
- Subjects: Technology -- Study and teaching -- South Africa -- Eastern Cape Technology -- Study and teaching -- South Africa Rural schools -- South Africa -- Eastern Cape Education, Rural -- South Africa Winterberg schools trust
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1491 , http://hdl.handle.net/10962/d1003372
- Description: This qualitative study focused on a Technology Education programme for farm school teachers in the Eastern Cape province of South Africa. These teachers were faced with the challenge of incorporating Technology Education into their curriculum. The study was conducted within the context of an investigation into the conceptual nature of technology and an exploration of the theoretical underpinnings of Technology Education within both the international and South African context. Technology Education is being introduced into the South African curriculum against a background of educational transformation and the building of capacity to solve real life problems. This calls for a curriculum that will empower learners to be innovative, creative and skilled problem solvers. The introduction and incorporation of Technoiogy Education into the school curriculum poses a formidable challenge to farm schools in particular. Their unique history of neglect and legacy of underqualified teachers has made the introduction of any curriculum innovation process very difficult and challenging. This study analyses how an introductory Technology Education programme for farm school teachers in the Winterberg area of the Eastern Cape impacted~ on the teachers' professional and personal lives. It shows the importance of developing teclpological skills in conjunction with life skills in cO.ntributing to the empowerment, both in the work place and in the wider context, of rural school teachers. It highlights the need for supportive in-service education programmes and strengthens the argument for an integrative and mulitidisciplinary approach to the introduction of Technology Education in farm schools. Data was collected by means of questionnaires, interviews and photographs.
- Full Text:
- Date Issued: 2000
Determining the essential traits for successful retail pharmacists in the Port Elizabeth-Uitenhage metropole
- Authors: Melamed, Graham Morrison
- Date: 2000
- Subjects: Retail trade -- Port Elizabeth -- South Africa , Pharmacists -- South Africa , Pharmacy management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10831 , http://hdl.handle.net/10948/22 , Retail trade -- Port Elizabeth -- South Africa , Pharmacists -- South Africa , Pharmacy management
- Description: The research problem addressed in this study was to determine whether successful retail pharmacists exhibited specific traits. To achieve this objective a theoretical schedule of traits was developed, using relevant literature in which traits of entrepreneurs are described. The theoretical list consisted of the possession of the following traits: The need to achieve; Confidence in their abilities; The successful management of risk; Creativity and the possession of vision; The tendency/ability to view changes as opportunities; Internal locus of control; Leadership; High level of motivation; Tenacity; Communication skills. Each trait of the schedule was analysed using the literature identified during the literature study. The theoretical list was then used to develop a questionnaire to test the degree to which retail pharmacists in the Greater Port Elizabeth/Uitenhage Metropole concur. The empirical results obtained indicate a strong concurrence with the theoretical list of traits of successful retail pharmacists that was developed in the study. This resulted in the theoretical schedule being confirmed and accepted as a list of traits possessed by successful retail pharmacists.
- Full Text:
- Date Issued: 2000
- Authors: Melamed, Graham Morrison
- Date: 2000
- Subjects: Retail trade -- Port Elizabeth -- South Africa , Pharmacists -- South Africa , Pharmacy management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10831 , http://hdl.handle.net/10948/22 , Retail trade -- Port Elizabeth -- South Africa , Pharmacists -- South Africa , Pharmacy management
- Description: The research problem addressed in this study was to determine whether successful retail pharmacists exhibited specific traits. To achieve this objective a theoretical schedule of traits was developed, using relevant literature in which traits of entrepreneurs are described. The theoretical list consisted of the possession of the following traits: The need to achieve; Confidence in their abilities; The successful management of risk; Creativity and the possession of vision; The tendency/ability to view changes as opportunities; Internal locus of control; Leadership; High level of motivation; Tenacity; Communication skills. Each trait of the schedule was analysed using the literature identified during the literature study. The theoretical list was then used to develop a questionnaire to test the degree to which retail pharmacists in the Greater Port Elizabeth/Uitenhage Metropole concur. The empirical results obtained indicate a strong concurrence with the theoretical list of traits of successful retail pharmacists that was developed in the study. This resulted in the theoretical schedule being confirmed and accepted as a list of traits possessed by successful retail pharmacists.
- Full Text:
- Date Issued: 2000
Development of a Human Resource development strategy for the Border-Kei motor industry cluster
- Authors: Maritz, Andre
- Date: 2000
- Subjects: Manpower policy , Automobile industry and trade -- South Africa , Automobile industry and trade -- Management , Personnel management -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10832 , http://hdl.handle.net/10948/23 , Manpower policy , Automobile industry and trade -- South Africa , Automobile industry and trade -- Management , Personnel management -- South Africa
- Description: DaimlerChrysler’s investment of R 1.4 billion in its East London Plant has resulted in the formation and development of an industry cluster, with DaimlerChrysler as the main industry driver. The rest of the cluster is made up of suppliers to the motor industry, as well as organisations involved in attracting and stimulating economic development in the region. The investment by DaimlerChrysler signalled the entry of DaimlerChrysler South Africa (DCSA) into global markets, supplying right-hand drive C-Class vehicles to the rest of the world. As a global player, world-class quality standards are expected of DCSA and, in turn, their suppliers. World-Class skills are therefore expected of the employees from all of the organisations within the cluster. This factor poses a challenge to South African organisations who are subjected to and challenged by the legislation that seeks to address and correct the societal imbalance of the past. The research problem addressed in this study was two-fold. The first objective was to determine whether or not there was a competitive advantage to be gained by being part of an industry cluster. The second objective was to determine how suppliers to DCSA from within the cluster developed world-class skills despite the constraints imposed upon them by South African legislation. To achieve these objectives, a theoretical study was conducted on existing conditions within clusters worldwide, as well as on methods being implemented by global organisations to develop world-class skills. An empirical study, covering the topics of competitive advantage and developing world-class skills, was developed and sent to suppliers of DCSA to test the degree of concurrence between methods implemented in the Border-Kei Motor Industry Cluster and global organisations elsewhere in the world. The results of the empirical study indicated a strong concurrence in many of the factors, and essentially only differed in instances where a cluster was more developed.
- Full Text:
- Date Issued: 2000
- Authors: Maritz, Andre
- Date: 2000
- Subjects: Manpower policy , Automobile industry and trade -- South Africa , Automobile industry and trade -- Management , Personnel management -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10832 , http://hdl.handle.net/10948/23 , Manpower policy , Automobile industry and trade -- South Africa , Automobile industry and trade -- Management , Personnel management -- South Africa
- Description: DaimlerChrysler’s investment of R 1.4 billion in its East London Plant has resulted in the formation and development of an industry cluster, with DaimlerChrysler as the main industry driver. The rest of the cluster is made up of suppliers to the motor industry, as well as organisations involved in attracting and stimulating economic development in the region. The investment by DaimlerChrysler signalled the entry of DaimlerChrysler South Africa (DCSA) into global markets, supplying right-hand drive C-Class vehicles to the rest of the world. As a global player, world-class quality standards are expected of DCSA and, in turn, their suppliers. World-Class skills are therefore expected of the employees from all of the organisations within the cluster. This factor poses a challenge to South African organisations who are subjected to and challenged by the legislation that seeks to address and correct the societal imbalance of the past. The research problem addressed in this study was two-fold. The first objective was to determine whether or not there was a competitive advantage to be gained by being part of an industry cluster. The second objective was to determine how suppliers to DCSA from within the cluster developed world-class skills despite the constraints imposed upon them by South African legislation. To achieve these objectives, a theoretical study was conducted on existing conditions within clusters worldwide, as well as on methods being implemented by global organisations to develop world-class skills. An empirical study, covering the topics of competitive advantage and developing world-class skills, was developed and sent to suppliers of DCSA to test the degree of concurrence between methods implemented in the Border-Kei Motor Industry Cluster and global organisations elsewhere in the world. The results of the empirical study indicated a strong concurrence in many of the factors, and essentially only differed in instances where a cluster was more developed.
- Full Text:
- Date Issued: 2000
Development of a model of factors promoting team effectiveness in the automotive component industry
- Authors: Hutton, Timothy Strathearn
- Date: 2000
- Subjects: Teams in the workplace , Automobile industry and trade -- Management , Automobile industry and trade -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10833 , http://hdl.handle.net/10948/24 , Teams in the workplace , Automobile industry and trade -- Management , Automobile industry and trade -- South Africa
- Description: The research problem addressed in this study was to determine what makes a work team successful. To achieve this objective a theoretical model of factors promoting team effectiveness was developed, using relevant literature in which models for team effectiveness are described. The theoretical model consisted of the following factors: Individual background factors; Facilitation; Team Factors; Synergy; Team effectiveness; Organisational factors. Each factor of the model was broken down into dimensions that were then analysed using literature identified during the literature study. The theoretical model was then used to develop a questionnaire to test the degree to which managers working for automotive component manufacturers in the Port Elizabeth /Uitenhage magisterial district and falling under Chapter III of the Bargaining Council for the Motor Industry concur. The empirical results obtained indicate a strong concurrence with the theoretical model of factors promoting team effectiveness that was developed in the study. This resulted in the theoretical model being confirmed and being accepted as a model of factors promoting team effectiveness.
- Full Text:
- Date Issued: 2000
- Authors: Hutton, Timothy Strathearn
- Date: 2000
- Subjects: Teams in the workplace , Automobile industry and trade -- Management , Automobile industry and trade -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10833 , http://hdl.handle.net/10948/24 , Teams in the workplace , Automobile industry and trade -- Management , Automobile industry and trade -- South Africa
- Description: The research problem addressed in this study was to determine what makes a work team successful. To achieve this objective a theoretical model of factors promoting team effectiveness was developed, using relevant literature in which models for team effectiveness are described. The theoretical model consisted of the following factors: Individual background factors; Facilitation; Team Factors; Synergy; Team effectiveness; Organisational factors. Each factor of the model was broken down into dimensions that were then analysed using literature identified during the literature study. The theoretical model was then used to develop a questionnaire to test the degree to which managers working for automotive component manufacturers in the Port Elizabeth /Uitenhage magisterial district and falling under Chapter III of the Bargaining Council for the Motor Industry concur. The empirical results obtained indicate a strong concurrence with the theoretical model of factors promoting team effectiveness that was developed in the study. This resulted in the theoretical model being confirmed and being accepted as a model of factors promoting team effectiveness.
- Full Text:
- Date Issued: 2000
Development of the components of a low cost, distributed facial virtual conferencing system
- Authors: Panagou, Soterios
- Date: 2000 , 2011-11-10
- Subjects: Virtual computer systems , Virtual reality , Computer conferencing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4622 , http://hdl.handle.net/10962/d1006490 , Virtual computer systems , Virtual reality , Computer conferencing
- Description: This thesis investigates the development of a low cost, component based facial virtual conferencing system. The design is decomposed into an encoding phase and a decoding phase, which communicate with each other via a network connection. The encoding phase is composed of three components: model acquisition (which handles avatar generation), pose estimation and expression analysis. Audio is not considered part of the encoding and decoding process, and as such is not evaluated. The model acquisition component is implemented using a visual hull reconstruction algorithm that is able to reconstruct real-world objects using only sets of images of the object as input. The object to be reconstructed is assumed to lie in a bounding volume of voxels. The reconstruction process involves the following stages: - Space carving for basic shape extraction; - Isosurface extraction to remove voxels not part of the surface of the reconstruction; - Mesh connection to generate a closed, connected polyhedral mesh; - Texture generation. Texturing is achieved by Gouraud shading the reconstruction with a vertex colour map; - Mesh decimation to simplify the object. The original algorithm has complexity O(n), but suffers from an inability to reconstruct concave surfaces that do not form part of the visual hull of the object. A novel extension to this algorithm based on Normalised Cross Correlation (NCC) is proposed to overcome this problem. An extension to speed up traditional NCC evaluations is proposed which reduces the NCC search space from a 2D search problem down to a single evaluation. Pose estimation and expression analysis are performed by tracking six fiducial points on the face of a subject. A tracking algorithm is developed that uses Normalised Cross Correlation to facilitate robust tracking that is invariant to changing lighting conditions, rotations and scaling. Pose estimation involves the recovery of the head position and orientation through the tracking of the triangle formed by the subject's eyebrows and nose tip. A rule-based evaluation of points that are tracked around the subject's mouth forms the basis of the expression analysis. A user assisted feedback loop and caching mechanism is used to overcome tracking errors due to fast motion or occlusions. The NCC tracker is shown to achieve a tracking performance of 10 fps when tracking the six fiducial points. The decoding phase is divided into 3 tasks, namely: avatar movement, expression generation and expression management. Avatar movement is implemented using the base VR system. Expression generation is facilitated using a Vertex Interpolation Deformation method. A weighting system is proposed for expression management. Its function is to gradually transform from one expression to the next. The use of the vertex interpolation method allows real-time deformations of the avatar representation, achieving 16 fps when applied to a model consisting of 7500 vertices. An Expression Parameter Lookup Table (EPLT) facilitates an independent mapping between the two phases. It defines a list of generic expressions that are known to the system and associates an Expression ID with each one. For each generic expression, it relates the expression analysis rules for any subject with the expression generation parameters for any avatar model. The result is that facial expression replication between any subject and avatar combination can be performed by transferring only the Expression ID from the encoder application to the decoder application. The ideas developed in the thesis are demonstrated in an implementation using the CoRgi Virtual Reality system. It is shown that the virtual-conferencing application based on this design requires only a bandwidth of 2 Kbps. , Adobe Acrobat Pro 9.4.6 , Adobe Acrobat 9.46 Paper Capture Plug-in
- Full Text:
- Date Issued: 2000
- Authors: Panagou, Soterios
- Date: 2000 , 2011-11-10
- Subjects: Virtual computer systems , Virtual reality , Computer conferencing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4622 , http://hdl.handle.net/10962/d1006490 , Virtual computer systems , Virtual reality , Computer conferencing
- Description: This thesis investigates the development of a low cost, component based facial virtual conferencing system. The design is decomposed into an encoding phase and a decoding phase, which communicate with each other via a network connection. The encoding phase is composed of three components: model acquisition (which handles avatar generation), pose estimation and expression analysis. Audio is not considered part of the encoding and decoding process, and as such is not evaluated. The model acquisition component is implemented using a visual hull reconstruction algorithm that is able to reconstruct real-world objects using only sets of images of the object as input. The object to be reconstructed is assumed to lie in a bounding volume of voxels. The reconstruction process involves the following stages: - Space carving for basic shape extraction; - Isosurface extraction to remove voxels not part of the surface of the reconstruction; - Mesh connection to generate a closed, connected polyhedral mesh; - Texture generation. Texturing is achieved by Gouraud shading the reconstruction with a vertex colour map; - Mesh decimation to simplify the object. The original algorithm has complexity O(n), but suffers from an inability to reconstruct concave surfaces that do not form part of the visual hull of the object. A novel extension to this algorithm based on Normalised Cross Correlation (NCC) is proposed to overcome this problem. An extension to speed up traditional NCC evaluations is proposed which reduces the NCC search space from a 2D search problem down to a single evaluation. Pose estimation and expression analysis are performed by tracking six fiducial points on the face of a subject. A tracking algorithm is developed that uses Normalised Cross Correlation to facilitate robust tracking that is invariant to changing lighting conditions, rotations and scaling. Pose estimation involves the recovery of the head position and orientation through the tracking of the triangle formed by the subject's eyebrows and nose tip. A rule-based evaluation of points that are tracked around the subject's mouth forms the basis of the expression analysis. A user assisted feedback loop and caching mechanism is used to overcome tracking errors due to fast motion or occlusions. The NCC tracker is shown to achieve a tracking performance of 10 fps when tracking the six fiducial points. The decoding phase is divided into 3 tasks, namely: avatar movement, expression generation and expression management. Avatar movement is implemented using the base VR system. Expression generation is facilitated using a Vertex Interpolation Deformation method. A weighting system is proposed for expression management. Its function is to gradually transform from one expression to the next. The use of the vertex interpolation method allows real-time deformations of the avatar representation, achieving 16 fps when applied to a model consisting of 7500 vertices. An Expression Parameter Lookup Table (EPLT) facilitates an independent mapping between the two phases. It defines a list of generic expressions that are known to the system and associates an Expression ID with each one. For each generic expression, it relates the expression analysis rules for any subject with the expression generation parameters for any avatar model. The result is that facial expression replication between any subject and avatar combination can be performed by transferring only the Expression ID from the encoder application to the decoder application. The ideas developed in the thesis are demonstrated in an implementation using the CoRgi Virtual Reality system. It is shown that the virtual-conferencing application based on this design requires only a bandwidth of 2 Kbps. , Adobe Acrobat Pro 9.4.6 , Adobe Acrobat 9.46 Paper Capture Plug-in
- Full Text:
- Date Issued: 2000
Direct use values of secondary resources harvested from communal savannas in the Bushbuckridge lowveld, South Africa
- Shackleton, Charlie M, Shackleton, Sheona E
- Authors: Shackleton, Charlie M , Shackleton, Sheona E
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182798 , vital:43875 , xlink:href="https://www.cabdirect.org/cabdirect/abstract/20000614194"
- Description: This study reports on the direct use value of secondary resources harvested by rural communities in a savanna region of South Africa. Data pertaining to the use, amount and direct use value of 11 secondary resources were presented individually, along with a final composite value. Only five resources (fuelwood, construction wood, edible fruits, edible herbs, and medicinal plants), individually accounted for more than 10% of the total value per hectare (US$ 141), and together they represented over 94% of the total value per hectare. On a per household basis, only 3 of the 11 resources contributed 10% or more to the total direct use value (US$ 386 used at home and US$ 767 traded), and together contributed greater than 71% of the total direct use value per household. Two-thirds of the value per household was traded locally with other households or regionally, rather than consumed at home. The total value per hectare compared favourably with other land uses within the region, except for capital intensive enterprises. The returns to collecting and selling secondary resources were higher than those paid for local agricultural wage labour. The extraction rates of several of the secondary resources are probably sustainable but not for the more important ones such as fuelwood, construction wood and medicinal plants.
- Full Text:
- Date Issued: 2000
- Authors: Shackleton, Charlie M , Shackleton, Sheona E
- Date: 2000
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/182798 , vital:43875 , xlink:href="https://www.cabdirect.org/cabdirect/abstract/20000614194"
- Description: This study reports on the direct use value of secondary resources harvested by rural communities in a savanna region of South Africa. Data pertaining to the use, amount and direct use value of 11 secondary resources were presented individually, along with a final composite value. Only five resources (fuelwood, construction wood, edible fruits, edible herbs, and medicinal plants), individually accounted for more than 10% of the total value per hectare (US$ 141), and together they represented over 94% of the total value per hectare. On a per household basis, only 3 of the 11 resources contributed 10% or more to the total direct use value (US$ 386 used at home and US$ 767 traded), and together contributed greater than 71% of the total direct use value per household. Two-thirds of the value per household was traded locally with other households or regionally, rather than consumed at home. The total value per hectare compared favourably with other land uses within the region, except for capital intensive enterprises. The returns to collecting and selling secondary resources were higher than those paid for local agricultural wage labour. The extraction rates of several of the secondary resources are probably sustainable but not for the more important ones such as fuelwood, construction wood and medicinal plants.
- Full Text:
- Date Issued: 2000
Discussion document prepared for COSATU Gender Conference
- NALEDI
- Authors: NALEDI
- Date: 2000
- Subjects: NALEDI
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/151190 , vital:39037
- Description: Despite the massive contribution women make around the world, they still fall into the category of the poorest and the most oppressed. Women have borne the brunt of the social costs of the changes in the world economy such as globalisation, increased international competition, structural adjustment and the deregulation of labour legislation. Massive technological advances have done little to benefit women around the world. In fact, in many instances it has actually increased their hardships. Multinational companies search the globe for areas that offer cheap labour and poor working conditions. Globally, women make up the bulk of the army of so-called “flexible”, cheap workers sought after by employers anxious to increase their profits. It is women who are mostly to be found in sweatshops and who are least likely to be organised. In South Africa, there is already a significant trend of homeworking in the clothing sector and casualisation in the retail and other sectors. And when they are organised into unions, women struggle to be recognised as leaders in those movements.
- Full Text:
- Date Issued: 2000
- Authors: NALEDI
- Date: 2000
- Subjects: NALEDI
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/151190 , vital:39037
- Description: Despite the massive contribution women make around the world, they still fall into the category of the poorest and the most oppressed. Women have borne the brunt of the social costs of the changes in the world economy such as globalisation, increased international competition, structural adjustment and the deregulation of labour legislation. Massive technological advances have done little to benefit women around the world. In fact, in many instances it has actually increased their hardships. Multinational companies search the globe for areas that offer cheap labour and poor working conditions. Globally, women make up the bulk of the army of so-called “flexible”, cheap workers sought after by employers anxious to increase their profits. It is women who are mostly to be found in sweatshops and who are least likely to be organised. In South Africa, there is already a significant trend of homeworking in the clothing sector and casualisation in the retail and other sectors. And when they are organised into unions, women struggle to be recognised as leaders in those movements.
- Full Text:
- Date Issued: 2000
Distributed authentication for resource control
- Authors: Burdis, Keith Robert
- Date: 2000
- Subjects: Computers -- Access control , Data protection , Computer networks -- Security measures , Electronic data processing departments -- Security measures
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4630 , http://hdl.handle.net/10962/d1006512 , Computers -- Access control , Data protection , Computer networks -- Security measures , Electronic data processing departments -- Security measures
- Description: This thesis examines distributed authentication in the process of controlling computing resources. We investigate user sign-on and two of the main authentication technologies that can be used to control a resource through authentication and providing additional security services. The problems with the existing sign-on scenario are that users have too much credential information to manage and are prompted for this information too often. Single Sign-On (SSO) is a viable solution to this problem if physical procedures are introduced to minimise the risks associated with its use. The Generic Security Services API (GSS-API) provides security services in a manner in- dependent of the environment in which these security services are used, encapsulating security functionality and insulating users from changes in security technology. The un- derlying security functionality is provided by GSS-API mechanisms. We developed the Secure Remote Password GSS-API Mechanism (SRPGM) to provide a mechanism that has low infrastructure requirements, is password-based and does not require the use of long-term asymmetric keys. We provide implementations of the Java GSS-API bindings and the LIPKEY and SRPGM GSS-API mechanisms. The Secure Authentication and Security Layer (SASL) provides security to connection- based Internet protocols. After finding deficiencies in existing SASL mechanisms we de- veloped the Secure Remote Password SASL mechanism (SRP-SASL) that provides strong password-based authentication and countermeasures against known attacks, while still be- ing simple and easy to implement. We provide implementations of the Java SASL binding and several SASL mechanisms, including SRP-SASL.
- Full Text:
- Date Issued: 2000
- Authors: Burdis, Keith Robert
- Date: 2000
- Subjects: Computers -- Access control , Data protection , Computer networks -- Security measures , Electronic data processing departments -- Security measures
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4630 , http://hdl.handle.net/10962/d1006512 , Computers -- Access control , Data protection , Computer networks -- Security measures , Electronic data processing departments -- Security measures
- Description: This thesis examines distributed authentication in the process of controlling computing resources. We investigate user sign-on and two of the main authentication technologies that can be used to control a resource through authentication and providing additional security services. The problems with the existing sign-on scenario are that users have too much credential information to manage and are prompted for this information too often. Single Sign-On (SSO) is a viable solution to this problem if physical procedures are introduced to minimise the risks associated with its use. The Generic Security Services API (GSS-API) provides security services in a manner in- dependent of the environment in which these security services are used, encapsulating security functionality and insulating users from changes in security technology. The un- derlying security functionality is provided by GSS-API mechanisms. We developed the Secure Remote Password GSS-API Mechanism (SRPGM) to provide a mechanism that has low infrastructure requirements, is password-based and does not require the use of long-term asymmetric keys. We provide implementations of the Java GSS-API bindings and the LIPKEY and SRPGM GSS-API mechanisms. The Secure Authentication and Security Layer (SASL) provides security to connection- based Internet protocols. After finding deficiencies in existing SASL mechanisms we de- veloped the Secure Remote Password SASL mechanism (SRP-SASL) that provides strong password-based authentication and countermeasures against known attacks, while still be- ing simple and easy to implement. We provide implementations of the Java SASL binding and several SASL mechanisms, including SRP-SASL.
- Full Text:
- Date Issued: 2000
Divine
- Priscilia Ngando (lead vocal), Mevio-Mayo, Dany Mouanga, Mouasso (rhythm guitars), Aubin Sandjo, Scorpionkabambay, Mouche Bass (bass guitar), Dany Mouanga, Eric Sefu (solo guitar), Aubin Sandjo, Paul Balong (keyboard), Abel Massock, Fabo Claude, Nono (chorus), Priscilia Ngando (composer), Aubin Sandjo (drum, percussion, keyboard), Alhadji Mallam Issa (talking drum), Moussa Haissam
- Authors: Priscilia Ngando (lead vocal) , Mevio-Mayo, Dany Mouanga, Mouasso (rhythm guitars) , Aubin Sandjo, Scorpionkabambay, Mouche Bass (bass guitar) , Dany Mouanga, Eric Sefu (solo guitar) , Aubin Sandjo, Paul Balong (keyboard) , Abel Massock, Fabo Claude, Nono (chorus) , Priscilia Ngando (composer) , Aubin Sandjo (drum, percussion, keyboard) , Alhadji Mallam Issa (talking drum) , Moussa Haissam
- Date: 2000
- Subjects: Popular music , Popular music--Africa, West , Africa Cameroon Yaounde f-cm
- Language: English , French
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/130891 , vital:36495 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC47-09
- Description: Popular songs from Cameroon, featuring female vocal accompanied by keyboard, chorus, guitar, percussion and talking drum, playing West and Central African rhythms
- Full Text: false
- Date Issued: 2000
- Authors: Priscilia Ngando (lead vocal) , Mevio-Mayo, Dany Mouanga, Mouasso (rhythm guitars) , Aubin Sandjo, Scorpionkabambay, Mouche Bass (bass guitar) , Dany Mouanga, Eric Sefu (solo guitar) , Aubin Sandjo, Paul Balong (keyboard) , Abel Massock, Fabo Claude, Nono (chorus) , Priscilia Ngando (composer) , Aubin Sandjo (drum, percussion, keyboard) , Alhadji Mallam Issa (talking drum) , Moussa Haissam
- Date: 2000
- Subjects: Popular music , Popular music--Africa, West , Africa Cameroon Yaounde f-cm
- Language: English , French
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/130891 , vital:36495 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC47-09
- Description: Popular songs from Cameroon, featuring female vocal accompanied by keyboard, chorus, guitar, percussion and talking drum, playing West and Central African rhythms
- Full Text: false
- Date Issued: 2000
Don't look back
- Smokey Robinson, Ronald White (written by), Wyclef Jean (vocals), Wyclef Jean
- Authors: Smokey Robinson, Ronald White (written by) , Wyclef Jean (vocals) , Wyclef Jean
- Date: 2000
- Subjects: Rap (Music) , Popular music--Africa, West , Africa Senegal Dakar f-sg
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/130552 , vital:36436 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC44-06
- Description: Lyrical song in English
- Full Text: false
- Date Issued: 2000
- Authors: Smokey Robinson, Ronald White (written by) , Wyclef Jean (vocals) , Wyclef Jean
- Date: 2000
- Subjects: Rap (Music) , Popular music--Africa, West , Africa Senegal Dakar f-sg
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/130552 , vital:36436 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC44-06
- Description: Lyrical song in English
- Full Text: false
- Date Issued: 2000
Don't walk away
- Youssou N'Dour, John Sharp, Cameron McVey (written by), Habib Faye (bass), Sting, Youssour N'Dour (vocals), Kevin Armstrong (guitar), Babacar Faye (Senegalese percussion), Assane Thiam (Tama Senegalese talking drum), Johnny $, Youssou N'Dour
- Authors: Youssou N'Dour, John Sharp, Cameron McVey (written by) , Habib Faye (bass) , Sting, Youssour N'Dour (vocals) , Kevin Armstrong (guitar) , Babacar Faye (Senegalese percussion) , Assane Thiam (Tama Senegalese talking drum) , Johnny $, Youssou N'Dour
- Date: 2000
- Subjects: Rap (Music) , Popular music--Africa, West , Africa Senegal Dakar f-sg
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/130561 , vital:36438 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC44-07
- Description: Lyrical song in English
- Full Text: false
- Date Issued: 2000
- Authors: Youssou N'Dour, John Sharp, Cameron McVey (written by) , Habib Faye (bass) , Sting, Youssour N'Dour (vocals) , Kevin Armstrong (guitar) , Babacar Faye (Senegalese percussion) , Assane Thiam (Tama Senegalese talking drum) , Johnny $, Youssou N'Dour
- Date: 2000
- Subjects: Rap (Music) , Popular music--Africa, West , Africa Senegal Dakar f-sg
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/130561 , vital:36438 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC44-07
- Description: Lyrical song in English
- Full Text: false
- Date Issued: 2000
Don't walk away
- Youssou N'Dour, John Sharp, Cameron McVey (written by), Habib Faye (bass), Sting, Youssour N'Dour (vocals), Kevin Armstrong (guitar), Babacar Faye (Senegalese percussion), Assane Thiam (Tama Senegalese talking drum), Johnny $, Youssou N'Dour
- Authors: Youssou N'Dour, John Sharp, Cameron McVey (written by) , Habib Faye (bass) , Sting, Youssour N'Dour (vocals) , Kevin Armstrong (guitar) , Babacar Faye (Senegalese percussion) , Assane Thiam (Tama Senegalese talking drum) , Johnny $, Youssou N'Dour
- Date: 2000
- Subjects: Rap (Music) , Popular music--Africa, West , Africa Senegal Dakar f-sg
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/130574 , vital:36437 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC44-07
- Description: Lyrical song in English
- Full Text: false
- Date Issued: 2000
- Authors: Youssou N'Dour, John Sharp, Cameron McVey (written by) , Habib Faye (bass) , Sting, Youssour N'Dour (vocals) , Kevin Armstrong (guitar) , Babacar Faye (Senegalese percussion) , Assane Thiam (Tama Senegalese talking drum) , Johnny $, Youssou N'Dour
- Date: 2000
- Subjects: Rap (Music) , Popular music--Africa, West , Africa Senegal Dakar f-sg
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/130574 , vital:36437 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC44-07
- Description: Lyrical song in English
- Full Text: false
- Date Issued: 2000
Donor conditionalities and democratisation in Kenya, 1991-1997
- Authors: Muriuki, Irene
- Date: 2000
- Subjects: Economic assistance -- Political aspects -- Kenya , Democracy -- Kenya , Elections -- Kenya , Kenya -- Politics and government -- 1978-2002
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2812 , http://hdl.handle.net/10962/d1003022 , Economic assistance -- Political aspects -- Kenya , Democracy -- Kenya , Elections -- Kenya , Kenya -- Politics and government -- 1978-2002
- Description: The end of the Cold War and the collapse of the Soviet Union has encouraged democratisation in most parts of Africa. At the same time, Western donors' attitudes towards r~cipients of foreign aid have changed. This has resulted in a new practice, which attempts to force Third World states to move toward liberal democracy by conditioning lending on the holding of mUlti-party elections. In Africa this has resulted to the holding of multi-party elections. This study attempts to examine donor conditionalities and democratisation in Kenya by examining the results of 1992 and 1997 multi-party elections. Kenya attained independence from the British and ushered in a multi-party democracy in 1963. Since then, the country has undergone a full circle of political development, starting with a multi-party democracy at independence, through a one party dictatorship between 1982 and 1992 and back to a multi-party democracy in 1993. The need to satisfy foreign donors forced the leadership to amend Section 2(A) of Kenya' s constitution that had legalised single-party rule in 1982 thus allowing plural politics. The externally pressured transition to multi-party democracy though has resulted in increased corruption, state-sponsored ethnic violence, continued political authoritarianism and disastrous economic mismanagement of what was once considered a model for the continent. This study urges that Western donors should focus less on elections and more on the fostering of democratic institutions through breaking patterns of neo-patrimonial rule that have inforn1ed and continue to inform politics in Kenya. Political reforms have been resisted by the incumbency in the fear tha! they may curtail the power of the political leadership whose main objective has been to cling to power.
- Full Text:
- Date Issued: 2000
- Authors: Muriuki, Irene
- Date: 2000
- Subjects: Economic assistance -- Political aspects -- Kenya , Democracy -- Kenya , Elections -- Kenya , Kenya -- Politics and government -- 1978-2002
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2812 , http://hdl.handle.net/10962/d1003022 , Economic assistance -- Political aspects -- Kenya , Democracy -- Kenya , Elections -- Kenya , Kenya -- Politics and government -- 1978-2002
- Description: The end of the Cold War and the collapse of the Soviet Union has encouraged democratisation in most parts of Africa. At the same time, Western donors' attitudes towards r~cipients of foreign aid have changed. This has resulted in a new practice, which attempts to force Third World states to move toward liberal democracy by conditioning lending on the holding of mUlti-party elections. In Africa this has resulted to the holding of multi-party elections. This study attempts to examine donor conditionalities and democratisation in Kenya by examining the results of 1992 and 1997 multi-party elections. Kenya attained independence from the British and ushered in a multi-party democracy in 1963. Since then, the country has undergone a full circle of political development, starting with a multi-party democracy at independence, through a one party dictatorship between 1982 and 1992 and back to a multi-party democracy in 1993. The need to satisfy foreign donors forced the leadership to amend Section 2(A) of Kenya' s constitution that had legalised single-party rule in 1982 thus allowing plural politics. The externally pressured transition to multi-party democracy though has resulted in increased corruption, state-sponsored ethnic violence, continued political authoritarianism and disastrous economic mismanagement of what was once considered a model for the continent. This study urges that Western donors should focus less on elections and more on the fostering of democratic institutions through breaking patterns of neo-patrimonial rule that have inforn1ed and continue to inform politics in Kenya. Political reforms have been resisted by the incumbency in the fear tha! they may curtail the power of the political leadership whose main objective has been to cling to power.
- Full Text:
- Date Issued: 2000
Dynamic compensation for performance characteristic differences of wind generator coupled pumps
- Swanepoel, Pieter Frederick Renier
- Authors: Swanepoel, Pieter Frederick Renier
- Date: 2000
- Subjects: Wind pumps
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10806 , http://hdl.handle.net/10948/25 , Wind pumps
- Description: The lack of services such as electricity in the rural areas of South Africa has given rise to the use of pump water and the windmills. The ones in use currently are maintenance intensive. There is a corrosive element in water and this sometimes requires plastic or other non-corrosive materials to be used for pump components and pipes. Solar panels are expensive and have low efficiencies. Alternative energy systems such as diesel engine driven- mono pumps or -turbines or windmills are costly, which means that the overall efficiency must be maximized to reduce these costs.
- Full Text:
- Date Issued: 2000
- Authors: Swanepoel, Pieter Frederick Renier
- Date: 2000
- Subjects: Wind pumps
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10806 , http://hdl.handle.net/10948/25 , Wind pumps
- Description: The lack of services such as electricity in the rural areas of South Africa has given rise to the use of pump water and the windmills. The ones in use currently are maintenance intensive. There is a corrosive element in water and this sometimes requires plastic or other non-corrosive materials to be used for pump components and pipes. Solar panels are expensive and have low efficiencies. Alternative energy systems such as diesel engine driven- mono pumps or -turbines or windmills are costly, which means that the overall efficiency must be maximized to reduce these costs.
- Full Text:
- Date Issued: 2000
Education for environmental literacy : towards participatory action research in the secondary school science curriculum in Lesotho
- Authors: Mokuku, Tsepo
- Date: 2000
- Subjects: Environmental education -- Lesotho , Science -- Study and teaching (Secondary) -- Lesotho
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1503 , http://hdl.handle.net/10962/d1003385 , Environmental education -- Lesotho , Science -- Study and teaching (Secondary) -- Lesotho
- Description: The dependency of educators in Lesotho on externally developed curriculum theories and concepts is fundamental to issues of relevance of the school curricula. This study set out to develop the meaning of environmental literacy in the context of three secondary schools and to explore appropriate teaching methods for the development of this concept in the science curriculum. The participatory action research process involved a team of four science teachers, including the researcher, in partnership with an environmental centre. We progressively developed the meamng of environmental literacy by monitoring teaching innovations in the classroom, holding meetings and workshops and attending conferences where we shared classroom findings and reflected on our emerging understandings based on classroom experiences. Data collection involved: audio-recording of classroom lessons, interviews with teachers and students, audio-visual recording, classroom observations and students' questionnaires. The research process made apparent the complex nature of the process of clarifying and developing environmental literacy in this context. Classroom actiyities planned to inform the team's understanding of the meaning of environmental literacy and develop appropriate teaching methods encountered constraints associated with the education system and the legacy of colonialism. These contextual constraints crystallised the need for the education system to be transformed in order to make schools more conducive environments for the gevelopment of students' environmental literacy. While initially teachers were reluctant to engage in critical reflection, the research process did encourage the team to revise and expand their understandings of both environmental literacy in the science classroom, and the action research itself. The emerging meaning of environmental literacy in this context and how it may be developed among students does not involve a definition with prescriptive, effective teaching methods, but provides insights and understandings gained by the participants in their engagement with a reflective process of reconslructing meaning. I have come to understand environmental literacy during the study to be a process that should draw strongly on the local knowledge and understandings into the science curriculum, through participatory process-based curriculum development models.
- Full Text:
- Date Issued: 2000
- Authors: Mokuku, Tsepo
- Date: 2000
- Subjects: Environmental education -- Lesotho , Science -- Study and teaching (Secondary) -- Lesotho
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1503 , http://hdl.handle.net/10962/d1003385 , Environmental education -- Lesotho , Science -- Study and teaching (Secondary) -- Lesotho
- Description: The dependency of educators in Lesotho on externally developed curriculum theories and concepts is fundamental to issues of relevance of the school curricula. This study set out to develop the meaning of environmental literacy in the context of three secondary schools and to explore appropriate teaching methods for the development of this concept in the science curriculum. The participatory action research process involved a team of four science teachers, including the researcher, in partnership with an environmental centre. We progressively developed the meamng of environmental literacy by monitoring teaching innovations in the classroom, holding meetings and workshops and attending conferences where we shared classroom findings and reflected on our emerging understandings based on classroom experiences. Data collection involved: audio-recording of classroom lessons, interviews with teachers and students, audio-visual recording, classroom observations and students' questionnaires. The research process made apparent the complex nature of the process of clarifying and developing environmental literacy in this context. Classroom actiyities planned to inform the team's understanding of the meaning of environmental literacy and develop appropriate teaching methods encountered constraints associated with the education system and the legacy of colonialism. These contextual constraints crystallised the need for the education system to be transformed in order to make schools more conducive environments for the gevelopment of students' environmental literacy. While initially teachers were reluctant to engage in critical reflection, the research process did encourage the team to revise and expand their understandings of both environmental literacy in the science classroom, and the action research itself. The emerging meaning of environmental literacy in this context and how it may be developed among students does not involve a definition with prescriptive, effective teaching methods, but provides insights and understandings gained by the participants in their engagement with a reflective process of reconslructing meaning. I have come to understand environmental literacy during the study to be a process that should draw strongly on the local knowledge and understandings into the science curriculum, through participatory process-based curriculum development models.
- Full Text:
- Date Issued: 2000
Effect of water temperature on the biogeography of South African estuarine fishes associated with the subtropical/warm temperate subtraction zone
- Maree, R C, Booth, Anthony J, Whitfield, Alan K
- Authors: Maree, R C , Booth, Anthony J , Whitfield, Alan K
- Date: 2000
- Language: English
- Type: text , Article
- Identifier: vital:7133 , http://hdl.handle.net/10962/d1011776
- Description: Estuarine biogeographical regions along the southeastern coast of South Africa were investigated in terms of fish distribution and abundance patterns, with particular emphasis on the role of water temperature in influencing these patterns. Qualitative and quantitative analyses were conducted upon the ichthyofaunal assemblages to determine whether the location of the subtropical/warm temperate boundary corresponds to that proposed by Whitfield.(n1) Analyses included the distribution ranges of species associated with estuaries according to presence/absence data, cluster analysis of gill net catches in eight estuaries along the southeastern coast and the relative proportion of tropical to temperate marine species within these eight systems. Quantitative analysis indicated that the ichthyofaunal biogeographical regions are indeed a reflection of water temperature regimes and that the subtropical/warm temperate boundary is located between the Great Kei and Mbashe estuaries. A strong negative correlation was found between the number of temperate fish species and the mean of the minimum monthly temperatures recorded in the systems studied. Qualitative analysis revealed that a barrier appears to exist in the vicinity of the Swartkops estuary, which prevents the westward migration of tropical 'vagrants'. The influence of the Agulhas Current along the east coast and its divergence from the coastline in the Algoa Bay region, as well as upwelling phenomena on the southeast and south coasts are identified as major factors that influence marine and estuarine temperature regimes and therefore the ichythyofauna of this region.
- Full Text: false
- Date Issued: 2000
- Authors: Maree, R C , Booth, Anthony J , Whitfield, Alan K
- Date: 2000
- Language: English
- Type: text , Article
- Identifier: vital:7133 , http://hdl.handle.net/10962/d1011776
- Description: Estuarine biogeographical regions along the southeastern coast of South Africa were investigated in terms of fish distribution and abundance patterns, with particular emphasis on the role of water temperature in influencing these patterns. Qualitative and quantitative analyses were conducted upon the ichthyofaunal assemblages to determine whether the location of the subtropical/warm temperate boundary corresponds to that proposed by Whitfield.(n1) Analyses included the distribution ranges of species associated with estuaries according to presence/absence data, cluster analysis of gill net catches in eight estuaries along the southeastern coast and the relative proportion of tropical to temperate marine species within these eight systems. Quantitative analysis indicated that the ichthyofaunal biogeographical regions are indeed a reflection of water temperature regimes and that the subtropical/warm temperate boundary is located between the Great Kei and Mbashe estuaries. A strong negative correlation was found between the number of temperate fish species and the mean of the minimum monthly temperatures recorded in the systems studied. Qualitative analysis revealed that a barrier appears to exist in the vicinity of the Swartkops estuary, which prevents the westward migration of tropical 'vagrants'. The influence of the Agulhas Current along the east coast and its divergence from the coastline in the Algoa Bay region, as well as upwelling phenomena on the southeast and south coasts are identified as major factors that influence marine and estuarine temperature regimes and therefore the ichythyofauna of this region.
- Full Text: false
- Date Issued: 2000
Effect of wave exposure on growth and mortality rates of the mussel Perna perna: bottom up regulation of intertidal populations
- McQuaid, Christopher D, Lindsay, Tracy L
- Authors: McQuaid, Christopher D , Lindsay, Tracy L
- Date: 2000
- Language: English
- Type: Article
- Identifier: vital:6955 , http://hdl.handle.net/10962/d1011994
- Description: The effect of wave exposure on the growth of low-shore populations of Perna perna (Linnaeus) was determined using 3 independent approaches at 6 sites on the south coast of South Africa: (1) Individual marking; notches were filed on the growing edges of mussels in situ. After 111 d, growth from the mark to the new growing edge was measured. (2) Internal shell-growth bands; mussels from the mark recapture experiment were used to establish that growth bands are laid down tidally. Unmarked individuals were then used to measure growth over the last 60 tides. (3) Shepherd¹s length-composition analysis (SLCA); growth rates were determined from length-frequency distributions in 11 samples collected at 6 wk intervals over 15 mo. All 3 approaches showed that growth rate was approximately twice as fast on exposed as on sheltered shores (ANCOVA, p < 0.05 in all cases). Mean length for the first year of growth (averaged for the 3 methods) was 47 and 22 mm, respectively. There were, however, considerable differences among methods. Marking provided the lowest estimates of growth rates, and SLCA the highest. The mean mortality index (Z yr-1) was significantly higher and annual survival rate lower for exposed shores, indicating faster turnover under exposed conditions. Mean longevity on exposed shores (2.6 yr) was only one-third of estimated longevity on sheltered shores (6.7 yr). These findings show that degree of exposure has important interactions with growth and mortality of mussels on the low shore, and that these effects are independent of the effects of exposure on density. The findings also indicate strong bottom up regulation of mussel populations.
- Full Text:
- Date Issued: 2000
- Authors: McQuaid, Christopher D , Lindsay, Tracy L
- Date: 2000
- Language: English
- Type: Article
- Identifier: vital:6955 , http://hdl.handle.net/10962/d1011994
- Description: The effect of wave exposure on the growth of low-shore populations of Perna perna (Linnaeus) was determined using 3 independent approaches at 6 sites on the south coast of South Africa: (1) Individual marking; notches were filed on the growing edges of mussels in situ. After 111 d, growth from the mark to the new growing edge was measured. (2) Internal shell-growth bands; mussels from the mark recapture experiment were used to establish that growth bands are laid down tidally. Unmarked individuals were then used to measure growth over the last 60 tides. (3) Shepherd¹s length-composition analysis (SLCA); growth rates were determined from length-frequency distributions in 11 samples collected at 6 wk intervals over 15 mo. All 3 approaches showed that growth rate was approximately twice as fast on exposed as on sheltered shores (ANCOVA, p < 0.05 in all cases). Mean length for the first year of growth (averaged for the 3 methods) was 47 and 22 mm, respectively. There were, however, considerable differences among methods. Marking provided the lowest estimates of growth rates, and SLCA the highest. The mean mortality index (Z yr-1) was significantly higher and annual survival rate lower for exposed shores, indicating faster turnover under exposed conditions. Mean longevity on exposed shores (2.6 yr) was only one-third of estimated longevity on sheltered shores (6.7 yr). These findings show that degree of exposure has important interactions with growth and mortality of mussels on the low shore, and that these effects are independent of the effects of exposure on density. The findings also indicate strong bottom up regulation of mussel populations.
- Full Text:
- Date Issued: 2000
Effects of sustained elevated CO2 concentration and Nitrogen nutrition on wheat (Triticum aestivum L. cv Gamtoos)
- Authors: Kgope, Barney Stephen
- Date: 2000
- Subjects: Wheat -- Growth , Wheat -- Nutrition , Nitrogen fertilizers , Nitrogen in agriculture
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4205 , http://hdl.handle.net/10962/d1003774 , Wheat -- Growth , Wheat -- Nutrition , Nitrogen fertilizers , Nitrogen in agriculture
- Description: There is consensus that high CO2 results in enhanced growth and yield for most crop plants. However, most of these studies were carried out in the presence of adequate nutrients, which is also the case in agricultural systems (managed ecosystems). About 20% of the earth’s land mass have sufficiently low levels of nutrients to cause some kind of stress to plants. On the other hand, elevated [CO2] decreases foliar nutrient elements in plants and as a result partitioning of certain nutrient elements in plants is altered. Little data is available on the partitioning of most nutrient elements in plants, and this will definitely impact on growth and yield. To investigate this, wheat (Triticum aestivum L. c.v. Gamtoos) was grown in controlled environment cabinets at 360 and 700 µmol mol -1 CO2. The full Long-Ashton nutrient solution comprising of three-nitrogen concentrations ([N]) viz. (4,6 and 12 mM) was used to water plants everyday. The measurement of net assimilation rate (NAR), stomatal conductance (gs), transpiration rate (E), water use efficiency (WUE), foliar [N], nitrogen use efficiency (NUE) and growth parameters (total plant biomass (TPB), total plant height (TPH), leaf area (LA), shoot and root dry weight) were made 7 days after germination (7 DAG) till the onset of flowering. The increase in nitrogen supply in the order of 4, 6 and 12mM resulted in an increase in NAR, g_s_ , WUE and a decline in E under elevated [CO2]. Under elevated [CO2] NAR was observed to increase during the first two weeks reaching its maximum at 14 DAG, thereafter followed by a decline reaching its maximum at 28 DAG. This was later followed by an increase at 35 DAG onwards. Under elevated [CO2], NAR was increased significantly between the nitrogen regimes during the first (7-14 DAG) and the last two (35-42 DAG) weeks. The response of assimilation as a function of internal [CO2] (Ci), showed a decrease with age at ages 14, 28 and 35 DAG. This negatively affected the initial slope and the CO2 saturated photosynthetic rates under all treatments. This suggest that acclimation may have been as a result of both stomatal and biochemical limitations. All the photosynthetic pigment levels (chl_a_, chl_b_, chl_(a+b)_, and C_(x+c)_ ) increased with an increase in nitrogen supply from 4 to 6mM [N]. A 12mM [N] resulted in a significant decline in the photosynthetic pigment levels compared to a 6mM [N]. Chla remained higher than chlb under all treatments. Also, NAR was seen to increase and decrease concomitantly with the photosynthetic pigment levels. Foliar [N] was seen to decrease with an increase in nitrogen supply from 4 to 6 mM [N] under elevated [CO2] and the effects were adverse under the 4mM [N]. Under the 6mM N regime foliar [N] was positively correlated to NAR for elevated [CO2] grown plants. Similarly, E was positively correlated to foliar [N] under the same conditions. Elevated CO2 and increase in nitrogen supply had a pronounced effect on total plant height (TPH), total plant biomass (TPB), leaf area (LA), shoot and root dry weight and nitrogen use efficiency (NUE). The effects were more pronounced under a 6mM [N] as a result of high NUE. However, under 12mM [N] growth was not as expected as a result of lower NUE. Under all treatments shoot dry weight (SDW) was positively correlated to NUE. Anatomical studies revealed that total leaf and midrib thickness was significantly increased with an increase in nitrogen supply under elevated CO2 to support the larger leaf areas. There were no significant changes in the chloroplast ultrastructure as a result of the increase in nitrogen supply and CO2 enrichment. Starch grain surface area was seen to decline with an increase in nitrogen under both ambient and elevated CO2. Elevated CO2 and increase in nitrogen supply significantly increased total grain dry weight per plant by 47 and 46% respectively under 6 and 12mM [N]. In contrast, the increase was by about 21, 61 and 67% respectively under 4, 6 and 12mM [N] between the CO2 regimes.
- Full Text:
- Date Issued: 2000
- Authors: Kgope, Barney Stephen
- Date: 2000
- Subjects: Wheat -- Growth , Wheat -- Nutrition , Nitrogen fertilizers , Nitrogen in agriculture
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4205 , http://hdl.handle.net/10962/d1003774 , Wheat -- Growth , Wheat -- Nutrition , Nitrogen fertilizers , Nitrogen in agriculture
- Description: There is consensus that high CO2 results in enhanced growth and yield for most crop plants. However, most of these studies were carried out in the presence of adequate nutrients, which is also the case in agricultural systems (managed ecosystems). About 20% of the earth’s land mass have sufficiently low levels of nutrients to cause some kind of stress to plants. On the other hand, elevated [CO2] decreases foliar nutrient elements in plants and as a result partitioning of certain nutrient elements in plants is altered. Little data is available on the partitioning of most nutrient elements in plants, and this will definitely impact on growth and yield. To investigate this, wheat (Triticum aestivum L. c.v. Gamtoos) was grown in controlled environment cabinets at 360 and 700 µmol mol -1 CO2. The full Long-Ashton nutrient solution comprising of three-nitrogen concentrations ([N]) viz. (4,6 and 12 mM) was used to water plants everyday. The measurement of net assimilation rate (NAR), stomatal conductance (gs), transpiration rate (E), water use efficiency (WUE), foliar [N], nitrogen use efficiency (NUE) and growth parameters (total plant biomass (TPB), total plant height (TPH), leaf area (LA), shoot and root dry weight) were made 7 days after germination (7 DAG) till the onset of flowering. The increase in nitrogen supply in the order of 4, 6 and 12mM resulted in an increase in NAR, g_s_ , WUE and a decline in E under elevated [CO2]. Under elevated [CO2] NAR was observed to increase during the first two weeks reaching its maximum at 14 DAG, thereafter followed by a decline reaching its maximum at 28 DAG. This was later followed by an increase at 35 DAG onwards. Under elevated [CO2], NAR was increased significantly between the nitrogen regimes during the first (7-14 DAG) and the last two (35-42 DAG) weeks. The response of assimilation as a function of internal [CO2] (Ci), showed a decrease with age at ages 14, 28 and 35 DAG. This negatively affected the initial slope and the CO2 saturated photosynthetic rates under all treatments. This suggest that acclimation may have been as a result of both stomatal and biochemical limitations. All the photosynthetic pigment levels (chl_a_, chl_b_, chl_(a+b)_, and C_(x+c)_ ) increased with an increase in nitrogen supply from 4 to 6mM [N]. A 12mM [N] resulted in a significant decline in the photosynthetic pigment levels compared to a 6mM [N]. Chla remained higher than chlb under all treatments. Also, NAR was seen to increase and decrease concomitantly with the photosynthetic pigment levels. Foliar [N] was seen to decrease with an increase in nitrogen supply from 4 to 6 mM [N] under elevated [CO2] and the effects were adverse under the 4mM [N]. Under the 6mM N regime foliar [N] was positively correlated to NAR for elevated [CO2] grown plants. Similarly, E was positively correlated to foliar [N] under the same conditions. Elevated CO2 and increase in nitrogen supply had a pronounced effect on total plant height (TPH), total plant biomass (TPB), leaf area (LA), shoot and root dry weight and nitrogen use efficiency (NUE). The effects were more pronounced under a 6mM [N] as a result of high NUE. However, under 12mM [N] growth was not as expected as a result of lower NUE. Under all treatments shoot dry weight (SDW) was positively correlated to NUE. Anatomical studies revealed that total leaf and midrib thickness was significantly increased with an increase in nitrogen supply under elevated CO2 to support the larger leaf areas. There were no significant changes in the chloroplast ultrastructure as a result of the increase in nitrogen supply and CO2 enrichment. Starch grain surface area was seen to decline with an increase in nitrogen under both ambient and elevated CO2. Elevated CO2 and increase in nitrogen supply significantly increased total grain dry weight per plant by 47 and 46% respectively under 6 and 12mM [N]. In contrast, the increase was by about 21, 61 and 67% respectively under 4, 6 and 12mM [N] between the CO2 regimes.
- Full Text:
- Date Issued: 2000