Calibration and validation of satellite data (images) over inland water bodies and the effect caused by the adjacency towards them
- Authors: Faniso, Zimbini
- Date: 2018
- Subjects: Hydrology Remote sensing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10350 , vital:35400
- Description: Remote sensing of inland water quality is a particularly challenging satellite Earth observation (EO) application. This arises because inland water bodies are small and optically complex targets that are generally dark compared to surrounding land. Inland water bodies are source supplies of water for both living and non-living organisms, that include human beings hence they need an observation. The spatial distribution of water changes over time and that leads to issues in different sectors like agricultural sector, environmental services and ecological issues. Signal reaching the satellite is usually dominated by light scattered in the atmosphere. Aerosols are strongly variable atmospheric constituents and play a major role in generating this unwanted signal which must be quantified and removed before any conclusions about water state and condition. In order to see how the aerosols affected the water state the light scattered in the atmosphere will be observed through electromagnetic spectrum bands in the atmosphere. This study will analyse the visible and near infrared wavebands of the electromagnetic spectrum as well as where it will be easy to distinguish the atmospheric noise types. A field campaign has been executed at Roodeplaat dam near Pretoria relating to Calibration and Validation (CalVal) of the recently launched Sentinel 2 and Sentinel 3 satellites. In situ measurements were taken at Roodeplaat dam simultaneously with the satellite overpass. Atmospheric Radiative Transfer Modelling (RTM) is required to analyse the satellite surface measurement data that is in the form of radiant quantities. Aerosol models for radiative transfer have been evaluated and refined to improve retrieval accuracy of water-leaving radiance at Roodeplaat dam. A retrieval algorithm for water-leaving radiance (Lw) and remote-sensing reflectance has been developed to analyse the sensitivity of the retrieval to aerosol optical properties, sensitivities, as well as proposals for enhanced retrieval methods, are presented.
- Full Text:
- Date Issued: 2018
- Authors: Faniso, Zimbini
- Date: 2018
- Subjects: Hydrology Remote sensing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10350 , vital:35400
- Description: Remote sensing of inland water quality is a particularly challenging satellite Earth observation (EO) application. This arises because inland water bodies are small and optically complex targets that are generally dark compared to surrounding land. Inland water bodies are source supplies of water for both living and non-living organisms, that include human beings hence they need an observation. The spatial distribution of water changes over time and that leads to issues in different sectors like agricultural sector, environmental services and ecological issues. Signal reaching the satellite is usually dominated by light scattered in the atmosphere. Aerosols are strongly variable atmospheric constituents and play a major role in generating this unwanted signal which must be quantified and removed before any conclusions about water state and condition. In order to see how the aerosols affected the water state the light scattered in the atmosphere will be observed through electromagnetic spectrum bands in the atmosphere. This study will analyse the visible and near infrared wavebands of the electromagnetic spectrum as well as where it will be easy to distinguish the atmospheric noise types. A field campaign has been executed at Roodeplaat dam near Pretoria relating to Calibration and Validation (CalVal) of the recently launched Sentinel 2 and Sentinel 3 satellites. In situ measurements were taken at Roodeplaat dam simultaneously with the satellite overpass. Atmospheric Radiative Transfer Modelling (RTM) is required to analyse the satellite surface measurement data that is in the form of radiant quantities. Aerosol models for radiative transfer have been evaluated and refined to improve retrieval accuracy of water-leaving radiance at Roodeplaat dam. A retrieval algorithm for water-leaving radiance (Lw) and remote-sensing reflectance has been developed to analyse the sensitivity of the retrieval to aerosol optical properties, sensitivities, as well as proposals for enhanced retrieval methods, are presented.
- Full Text:
- Date Issued: 2018
Détournement : the art of troubling
- Authors: Wilby, Mark Owen
- Date: 2016
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/345 , vital:19950
- Description: Confidence in the form of, for example, commodified debt or the commodification of future value, is an increasingly large part of today’s globalised economy. This was alarmingly illustrated in 2008 by the repercussions of marketing unstable debt in the form of subprime mortgages in the United States leading to a precipitous global financial meltdown. That was a collapse of confidence writ large. At the same time, confidence is also a cornerstone of everyday social and professional life. The non-ZERO-sum project (exhibition title of practical submission in MFA fulfilment) interacts with the notion of confidence, and more particularly economic confidence. At the same time, the project takes the view that engagement from a fine art perspective would have an inherently inadequate vocabulary if restricted to a representative practice, and so a more interactive approach was sought. Research into the radical activism of the Situationists in the 1950s and 1960s, and particularly their tactic of détournement (the deliberate subversion of social or cultural practices), has informed and influenced the development of an interventionist technique summed up in this thesis as: The Art of Troubling. The Situationists had a dichotomous relationship with art. The group was initially made up mostly of artists and is in other instances referred to as an art movement. They saw art as the fulcrum for social and political change, and had their roots in the Dada, Surrealist, and Lettrist movements. As such, they also carried the genes of the notion of an anti-art, which varied in concept between art as a disruptive and propagandistic practice to the subsuming of art into other forms of social activity. This thesis, Détournement: The Art of Troubling, describes non-ZERO-sum as a bespoke methodology designed specifically for engagement with its particular topic. As such, the concept does not necessarily follow a template for situationist intervention. In 1962, a growing rift between the artists and the political theorists within the Situationist International tore the group in two. In conclusion of the non-ZERO-sum project, this thesis offers the observation that perhaps it was the political faction of the Situationists that had a more compelling idea of an art that functions through its very own subsumption.
- Full Text:
- Date Issued: 2016
- Authors: Wilby, Mark Owen
- Date: 2016
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: http://hdl.handle.net/10962/345 , vital:19950
- Description: Confidence in the form of, for example, commodified debt or the commodification of future value, is an increasingly large part of today’s globalised economy. This was alarmingly illustrated in 2008 by the repercussions of marketing unstable debt in the form of subprime mortgages in the United States leading to a precipitous global financial meltdown. That was a collapse of confidence writ large. At the same time, confidence is also a cornerstone of everyday social and professional life. The non-ZERO-sum project (exhibition title of practical submission in MFA fulfilment) interacts with the notion of confidence, and more particularly economic confidence. At the same time, the project takes the view that engagement from a fine art perspective would have an inherently inadequate vocabulary if restricted to a representative practice, and so a more interactive approach was sought. Research into the radical activism of the Situationists in the 1950s and 1960s, and particularly their tactic of détournement (the deliberate subversion of social or cultural practices), has informed and influenced the development of an interventionist technique summed up in this thesis as: The Art of Troubling. The Situationists had a dichotomous relationship with art. The group was initially made up mostly of artists and is in other instances referred to as an art movement. They saw art as the fulcrum for social and political change, and had their roots in the Dada, Surrealist, and Lettrist movements. As such, they also carried the genes of the notion of an anti-art, which varied in concept between art as a disruptive and propagandistic practice to the subsuming of art into other forms of social activity. This thesis, Détournement: The Art of Troubling, describes non-ZERO-sum as a bespoke methodology designed specifically for engagement with its particular topic. As such, the concept does not necessarily follow a template for situationist intervention. In 1962, a growing rift between the artists and the political theorists within the Situationist International tore the group in two. In conclusion of the non-ZERO-sum project, this thesis offers the observation that perhaps it was the political faction of the Situationists that had a more compelling idea of an art that functions through its very own subsumption.
- Full Text:
- Date Issued: 2016
Evaluating social media participation for successful marketing and communication by selected private game reserves, Eastern Cape, South Africa
- Authors: Booth, Tara
- Date: 2013
- Subjects: Social media -- Economic aspects , Online social networks -- Economic aspects , Game reserves -- South Africa -- Eastern Cape -- Marketing , Internet marketing -- Economic aspects , Social media -- Marketing , Tourism -- Marketing , Communication in management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:843 , http://hdl.handle.net/10962/d1015692
- Description: Social media has become one of the defining features of the technological advances known as Web 2.0. As social media has increased in popularity, so businesses are expected to participate. Social media platforms enable businesses to widely broadcast a message as well as interact directly with individual customers. Customers are also able to interact directly with one another and share information and reviews about products and services offered. This suits the tourism industry particularly well. Internationally, research has shown that individuals use social media and other online tools to research potential holiday destinations. In addition social media is used during travel to share snapshots and commentary as well as after travel, through reviews and recommendations on platforms such as TripAdvisor. However, few studies have investigated how tourism destinations use social media to attract new clients and retain existing clients. Very little research has been done on tourism and social media in South Africa despite the importance of this industry to Gross Domestic Product (GDP). This study focused on four-star establishments within the photographic wildlife tourism industry in the Eastern Cape of South Africa. An initial survey of social media participation was carried out within the framework set out by Chan and Guillet (2011); this was then followed up with interviews with selected managers. Results showed that, in general, Private Game Reserves (PGRs) had embraced social media as a communication and marketing platform; despite concerns raised about the lack of control over content as well as poor understanding of the influence social media might have on the bottom line. TripAdvisor, Facebook and Twitter were the most commonly used platforms due to management familiarity with the platform and their ease of use. Few lodges utilised blogs or content sites such as YouTube and management cited time commitments associated with this type of platform as a reason for non-participation. However, although most PGRs or lodges had a profile on social media, this did not always mean active participation. Frequently, lodges began updating but gradually stopped after a few months. It was noted however that only one of the lodges interviewed retained an individual whose sole responsibility was social media; generally lodges did not feel that a dedicated person was necessary. This may result in a lack of time available on the part of the individual responsible or simply be a case of not understanding the platform or how to use it effectively. However, none of the PGRs with poor social media participation responded to interview requests and therefore it was not possible to determine the reasons for their poor participation. Among those lodges that actively participated, most succeed in retaining fans and followers through consistent posting of relevant and interesting content as well as customised responses that encouraged fans or followers’ interaction. However, there did not appear to be any evidence of using social media to learn about fans and followers in order to better customise the lodge offerings. This may not be necessary in this type of industry as PGRs sell a specific product and have a limited ability to customise offerings. In addition, there may be other sources of market information which lodges prefer to use. Special offers, competitions and promotions had limited success on social media. Generally, lodges used social media to promote links to a dedicated competition or promotions page. In conclusion, the managers interviewed felt strongly that social media had made a measureable impact on the tourism industry and was a channel that was here to stay. Further research around the best practice and most effective use will enable PGRs to develop and maintain effective strategies for social media participation.
- Full Text:
- Date Issued: 2013
- Authors: Booth, Tara
- Date: 2013
- Subjects: Social media -- Economic aspects , Online social networks -- Economic aspects , Game reserves -- South Africa -- Eastern Cape -- Marketing , Internet marketing -- Economic aspects , Social media -- Marketing , Tourism -- Marketing , Communication in management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:843 , http://hdl.handle.net/10962/d1015692
- Description: Social media has become one of the defining features of the technological advances known as Web 2.0. As social media has increased in popularity, so businesses are expected to participate. Social media platforms enable businesses to widely broadcast a message as well as interact directly with individual customers. Customers are also able to interact directly with one another and share information and reviews about products and services offered. This suits the tourism industry particularly well. Internationally, research has shown that individuals use social media and other online tools to research potential holiday destinations. In addition social media is used during travel to share snapshots and commentary as well as after travel, through reviews and recommendations on platforms such as TripAdvisor. However, few studies have investigated how tourism destinations use social media to attract new clients and retain existing clients. Very little research has been done on tourism and social media in South Africa despite the importance of this industry to Gross Domestic Product (GDP). This study focused on four-star establishments within the photographic wildlife tourism industry in the Eastern Cape of South Africa. An initial survey of social media participation was carried out within the framework set out by Chan and Guillet (2011); this was then followed up with interviews with selected managers. Results showed that, in general, Private Game Reserves (PGRs) had embraced social media as a communication and marketing platform; despite concerns raised about the lack of control over content as well as poor understanding of the influence social media might have on the bottom line. TripAdvisor, Facebook and Twitter were the most commonly used platforms due to management familiarity with the platform and their ease of use. Few lodges utilised blogs or content sites such as YouTube and management cited time commitments associated with this type of platform as a reason for non-participation. However, although most PGRs or lodges had a profile on social media, this did not always mean active participation. Frequently, lodges began updating but gradually stopped after a few months. It was noted however that only one of the lodges interviewed retained an individual whose sole responsibility was social media; generally lodges did not feel that a dedicated person was necessary. This may result in a lack of time available on the part of the individual responsible or simply be a case of not understanding the platform or how to use it effectively. However, none of the PGRs with poor social media participation responded to interview requests and therefore it was not possible to determine the reasons for their poor participation. Among those lodges that actively participated, most succeed in retaining fans and followers through consistent posting of relevant and interesting content as well as customised responses that encouraged fans or followers’ interaction. However, there did not appear to be any evidence of using social media to learn about fans and followers in order to better customise the lodge offerings. This may not be necessary in this type of industry as PGRs sell a specific product and have a limited ability to customise offerings. In addition, there may be other sources of market information which lodges prefer to use. Special offers, competitions and promotions had limited success on social media. Generally, lodges used social media to promote links to a dedicated competition or promotions page. In conclusion, the managers interviewed felt strongly that social media had made a measureable impact on the tourism industry and was a channel that was here to stay. Further research around the best practice and most effective use will enable PGRs to develop and maintain effective strategies for social media participation.
- Full Text:
- Date Issued: 2013
Optimistic science: the effectiveness of economic methodology in achieving objectivity
- Authors: Holl, Ryan
- Date: 2012
- Subjects: Economics -- Methodology , Social epistemology , Knowledge, Theory of -- Science , Objectivity -- Science , Science -- Methodology , Optimism
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1105 , http://hdl.handle.net/10962/d1013393
- Description: This thesis examines the extent to which optimism has a bearing on objectivity in scientific inquiry. It is not, however, a psychological level examination into objectivity. Rather, the discussion focuses on collective attitudes, whether in the form of science or a more general public opinion. In essence, sources of optimism at the fundamental level of scientific inquiry are articulated with a careful attempt to differentiate between attitudes about the subject (methodology) and the object of study. The antithetical thread of optimism versus pessimism is teased out with the use of a joint case study of liberalism and Stalinism. The idea of antithesis, however, is contrasted by the fact that, although mirror image ideologies, these collective attitudes share a common faith in progress (albeit through different social mechanisms). This faith in progress provides the basis for the crux of the thesis as it moves to discuss scientific methodology. There is general agreement on what good science should look like and the possibility of progressive science can be articulated. However, it is also possible to highlight the conditions for degenerative science and to further link this to a degenerative social totality in which democracy and social progress are undermined. Economics is used as a case study and it is argued that dogmatic notions on progress have proved to be a major stumbling block to objectivity in the discipline. Furthermore, the implications on the real world are serious.
- Full Text:
- Date Issued: 2012
- Authors: Holl, Ryan
- Date: 2012
- Subjects: Economics -- Methodology , Social epistemology , Knowledge, Theory of -- Science , Objectivity -- Science , Science -- Methodology , Optimism
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1105 , http://hdl.handle.net/10962/d1013393
- Description: This thesis examines the extent to which optimism has a bearing on objectivity in scientific inquiry. It is not, however, a psychological level examination into objectivity. Rather, the discussion focuses on collective attitudes, whether in the form of science or a more general public opinion. In essence, sources of optimism at the fundamental level of scientific inquiry are articulated with a careful attempt to differentiate between attitudes about the subject (methodology) and the object of study. The antithetical thread of optimism versus pessimism is teased out with the use of a joint case study of liberalism and Stalinism. The idea of antithesis, however, is contrasted by the fact that, although mirror image ideologies, these collective attitudes share a common faith in progress (albeit through different social mechanisms). This faith in progress provides the basis for the crux of the thesis as it moves to discuss scientific methodology. There is general agreement on what good science should look like and the possibility of progressive science can be articulated. However, it is also possible to highlight the conditions for degenerative science and to further link this to a degenerative social totality in which democracy and social progress are undermined. Economics is used as a case study and it is argued that dogmatic notions on progress have proved to be a major stumbling block to objectivity in the discipline. Furthermore, the implications on the real world are serious.
- Full Text:
- Date Issued: 2012
Normative indications for Xhosa-speaking unskilled workers on the trail making test and the stroop test
- Authors: Andrews, Karen Anne Hope
- Date: 2008
- Subjects: Neuropsychology , Neuropsychological tests -- Sex differences , Educational tests and measurements -- Sex differences , Xhosa (African people) -- Education
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:2926 , http://hdl.handle.net/10962/d1002435 , Neuropsychology , Neuropsychological tests -- Sex differences , Educational tests and measurements -- Sex differences , Xhosa (African people) -- Education
- Description: The aim of the study was to produce preliminary normative indications for the Trail Making Test and the Stroop Test, administered in English, on a non-clinical sample of black, Xhosa-speaking, unskilled individuals (N = 33), with an educational level of 11 – 12 years, in two age categories (18 –29 and 30 – 40 years). The sample was equally distributed for gender and level of education. Participants, who were required to have a basic proficiency in English, were from traditionally black township schools with relatively disadvantaged quality of education. Within-sample age and gender effects were investigated. There were no significant age effects on the Trail Making Test, whereas there was one significant difference between age groups on the Stroop Test with respect to the Color-Word task, and a result that strongly approached significance on the Word task, with the younger group performing better than the older group. There were no significant gender effects on the Trail Making Test, whereas there was one significant difference between genders on the Stroop Test with respect to the Word task, and a result that approached significance on the Color task, with females performing better than males. Normative indications for both measures were compared to available normative data on western populations with higher levels and more advantaged quality of education. This comparison revealed consistently poorer performances for both the Trail Making Test and the Stroop Test, confirming the need for localised normative datasets to facilitate accurate neuropsychological diagnoses on culturally disadvantaged individuals.
- Full Text:
- Date Issued: 2008
- Authors: Andrews, Karen Anne Hope
- Date: 2008
- Subjects: Neuropsychology , Neuropsychological tests -- Sex differences , Educational tests and measurements -- Sex differences , Xhosa (African people) -- Education
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:2926 , http://hdl.handle.net/10962/d1002435 , Neuropsychology , Neuropsychological tests -- Sex differences , Educational tests and measurements -- Sex differences , Xhosa (African people) -- Education
- Description: The aim of the study was to produce preliminary normative indications for the Trail Making Test and the Stroop Test, administered in English, on a non-clinical sample of black, Xhosa-speaking, unskilled individuals (N = 33), with an educational level of 11 – 12 years, in two age categories (18 –29 and 30 – 40 years). The sample was equally distributed for gender and level of education. Participants, who were required to have a basic proficiency in English, were from traditionally black township schools with relatively disadvantaged quality of education. Within-sample age and gender effects were investigated. There were no significant age effects on the Trail Making Test, whereas there was one significant difference between age groups on the Stroop Test with respect to the Color-Word task, and a result that strongly approached significance on the Word task, with the younger group performing better than the older group. There were no significant gender effects on the Trail Making Test, whereas there was one significant difference between genders on the Stroop Test with respect to the Word task, and a result that approached significance on the Color task, with females performing better than males. Normative indications for both measures were compared to available normative data on western populations with higher levels and more advantaged quality of education. This comparison revealed consistently poorer performances for both the Trail Making Test and the Stroop Test, confirming the need for localised normative datasets to facilitate accurate neuropsychological diagnoses on culturally disadvantaged individuals.
- Full Text:
- Date Issued: 2008
The role of the trade union in post democratic South Africa
- Authors: Collins, Selwyn Charles
- Date: 2004
- Subjects: Labor unions -- South Africa , Labor policy -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11036 , http://hdl.handle.net/10948/354 , Labor unions -- South Africa , Labor policy -- South Africa
- Description: In South Africa, labour has played a central role in shaping the transition to democracy. It remained an open question as to whether labour could sustain it’s involvement during the period of consolidation after the first democratic elections. As was evident in other emerging democracies, economic liberalization often led to stagnation and high costs being imposed on workers, while weakening the state. South African trade unions thus faced formidable problems as they had to respond to rapid economic and industrial change. While being stubborn, South African trade unions remain adaptable enough to survive and grow into the 21st Century. In this dissertation, the writer examines the relevance of trade unions in contemporary South Africa and how they are coming to terms with the deregulated labour market, and the question of globalisation. We look at the emergence of new forms of collective bargaining, the growth of trade unions as partners in a changing workplace and the different ways trade unions are modernising themselves to attract new members. Labour when used as a collective force is capable of shaping democratization through the strategic use of power. Labour has the potential , through participation in negotiated compromises, to ensure that the costs of adjustments are not borne by workers alone. To this end, the South African trade union movement has developed innovative strategies and institutions.
- Full Text:
- Date Issued: 2004
- Authors: Collins, Selwyn Charles
- Date: 2004
- Subjects: Labor unions -- South Africa , Labor policy -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11036 , http://hdl.handle.net/10948/354 , Labor unions -- South Africa , Labor policy -- South Africa
- Description: In South Africa, labour has played a central role in shaping the transition to democracy. It remained an open question as to whether labour could sustain it’s involvement during the period of consolidation after the first democratic elections. As was evident in other emerging democracies, economic liberalization often led to stagnation and high costs being imposed on workers, while weakening the state. South African trade unions thus faced formidable problems as they had to respond to rapid economic and industrial change. While being stubborn, South African trade unions remain adaptable enough to survive and grow into the 21st Century. In this dissertation, the writer examines the relevance of trade unions in contemporary South Africa and how they are coming to terms with the deregulated labour market, and the question of globalisation. We look at the emergence of new forms of collective bargaining, the growth of trade unions as partners in a changing workplace and the different ways trade unions are modernising themselves to attract new members. Labour when used as a collective force is capable of shaping democratization through the strategic use of power. Labour has the potential , through participation in negotiated compromises, to ensure that the costs of adjustments are not borne by workers alone. To this end, the South African trade union movement has developed innovative strategies and institutions.
- Full Text:
- Date Issued: 2004
An evaluation of family poultry production systems in the Northern region
- Authors: Ranwedzi, Ndivhuho Emmanuel
- Date: 2002
- Subjects: Poultry -- Breeding , Poultry -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MTech (Agricultural Management)
- Identifier: vital:10962 , http://hdl.handle.net/10948/93 , Poultry -- Breeding , Poultry -- Feeding and feeds
- Description: Introduction : Family Poultry (FP) are birds of indigenous breeds living in almost symbiotic relationship with human communities. The chickens are usually free ranging, or have very limited restrains on their access to the village environment. African livestock population statistics for 1995 indicates poultry to be the most numerous species of farm animal (Anonymous, 1996a). More than 80% of poultry are kept in rural areas and contribute substantially to annual egg and meat production (Sonaiya, 1997). Throughout Africa poultry production stems from ancient traditional practices. FP is the most important type of poultry kept on the continent. In general, village producers keep small flocks of between 5 and 20 birds per household (Gueye, 1997a). Women and children play a key role in their management (Kitalyi, 1996). Because of its productivity, FP production has been neglected and is frequently considered by farmers as an insignificant occupation compared with other agricultural activities. Nevertheless, outside urban centers and especially in non-coastal areas, FP provides the population with a vital source of protein and income. In addition, they play an important role within the context of many social and/ or religious ceremonies. Although this type of poultry constitutes an important part of food security for rural households in South Africa, scientists have not explored this area of research for improving or recording this production system. Yet, FP survived for decades without being wiped out, in the interim, their keepers have gathered and stored a wealth of knowledge and experience, ensuring the survival of this genetic resource. The objective of this study was to collect the baseline data on FP production systems, determine their production constraints and achieve data for future use in the intervention strategies.
- Full Text:
- Date Issued: 2002
- Authors: Ranwedzi, Ndivhuho Emmanuel
- Date: 2002
- Subjects: Poultry -- Breeding , Poultry -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MTech (Agricultural Management)
- Identifier: vital:10962 , http://hdl.handle.net/10948/93 , Poultry -- Breeding , Poultry -- Feeding and feeds
- Description: Introduction : Family Poultry (FP) are birds of indigenous breeds living in almost symbiotic relationship with human communities. The chickens are usually free ranging, or have very limited restrains on their access to the village environment. African livestock population statistics for 1995 indicates poultry to be the most numerous species of farm animal (Anonymous, 1996a). More than 80% of poultry are kept in rural areas and contribute substantially to annual egg and meat production (Sonaiya, 1997). Throughout Africa poultry production stems from ancient traditional practices. FP is the most important type of poultry kept on the continent. In general, village producers keep small flocks of between 5 and 20 birds per household (Gueye, 1997a). Women and children play a key role in their management (Kitalyi, 1996). Because of its productivity, FP production has been neglected and is frequently considered by farmers as an insignificant occupation compared with other agricultural activities. Nevertheless, outside urban centers and especially in non-coastal areas, FP provides the population with a vital source of protein and income. In addition, they play an important role within the context of many social and/ or religious ceremonies. Although this type of poultry constitutes an important part of food security for rural households in South Africa, scientists have not explored this area of research for improving or recording this production system. Yet, FP survived for decades without being wiped out, in the interim, their keepers have gathered and stored a wealth of knowledge and experience, ensuring the survival of this genetic resource. The objective of this study was to collect the baseline data on FP production systems, determine their production constraints and achieve data for future use in the intervention strategies.
- Full Text:
- Date Issued: 2002
Jean Dubuffet : a study of his concepts pertaining to the alienation of the artist
- Authors: Mather-Pike, Richard
- Date: 1989
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:21086 , http://hdl.handle.net/10962/6290
- Description: I decided on an investigation into the nature of Dubuffet's remarks concerning the plight of the artist in modern societies, believing that the difficulties facing the artist are, at the time of this writing, still in force, and perhaps even more so now than they were in his day. These difficulties I believe, arise in the form of curtailments on personal and aesthetic freedoms brought about as the result of the artist's position in, and conformity to, the norms and values of his society. The problem is I believe, that these value systems not only censor or curb artistic freedom but actually restrict all individual enterprises by demanding that the indi vidual conform to the greater wish of the group, at the expense of his own creative and individual potential.
- Full Text:
- Date Issued: 1989
- Authors: Mather-Pike, Richard
- Date: 1989
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:21086 , http://hdl.handle.net/10962/6290
- Description: I decided on an investigation into the nature of Dubuffet's remarks concerning the plight of the artist in modern societies, believing that the difficulties facing the artist are, at the time of this writing, still in force, and perhaps even more so now than they were in his day. These difficulties I believe, arise in the form of curtailments on personal and aesthetic freedoms brought about as the result of the artist's position in, and conformity to, the norms and values of his society. The problem is I believe, that these value systems not only censor or curb artistic freedom but actually restrict all individual enterprises by demanding that the indi vidual conform to the greater wish of the group, at the expense of his own creative and individual potential.
- Full Text:
- Date Issued: 1989
Painting and the changing role of art
- Authors: Edwards, Veryan Courtenay
- Date: 1979
- Subjects: Painting Art and society
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2482 , http://hdl.handle.net/10962/d1011740
- Description: It is necessary to find out what the role of art is in order to see whether it changes. The role of art can be taken as synonymous with the words, 'function of art'. The role of art and the art work itself are inextricably linked. If we look at the role of art as analogous to a wheel we can look at the argument thus : the wheel exists in order to roll. Its function is to roll. The wheel's function of rolling informs us about its existence. Function and the wheel's existence cannot be separated. The role of art and the art work itself are inextricably tied. Intro. p. 1.
- Full Text:
- Date Issued: 1979
- Authors: Edwards, Veryan Courtenay
- Date: 1979
- Subjects: Painting Art and society
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:2482 , http://hdl.handle.net/10962/d1011740
- Description: It is necessary to find out what the role of art is in order to see whether it changes. The role of art can be taken as synonymous with the words, 'function of art'. The role of art and the art work itself are inextricably linked. If we look at the role of art as analogous to a wheel we can look at the argument thus : the wheel exists in order to roll. Its function is to roll. The wheel's function of rolling informs us about its existence. Function and the wheel's existence cannot be separated. The role of art and the art work itself are inextricably tied. Intro. p. 1.
- Full Text:
- Date Issued: 1979
Some aspects of the construction and implementation of error-correcting linear codes
- Authors: Booth, Geoffrey L
- Date: 1978
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:20967 , http://hdl.handle.net/10962/5718
- Description: From Conclusion: The study of error-correcting codes is now approximately 25 years old. The first known publication on the subject was in 1949 by M. Golay, who later did much research into the subject of perfect codes. It has been recently established that all the perfect codes are known. R.W. Hamming presented his perfect single-error correcting codes in 1950, in ~n article in the Bell System Technical Journal. These codes turned out to be a special case of the powerful Bose-Chaudhuri codes which were discovered around 1960. Various work has been done on the theory of minimal redundancy of codes for a given error-correcting performance, by Plotkin, Gilbert, Varshamov and others, between 1950 and 1960. The binary BCH codes were found to be so close to the theoretical bounds that, to date, no better codes have been discovered. Although the BCH codes are extremely efficient in terms of ratio of information to check digits, they are not easily, decoded with a minimal amount of apparatus. Petersen in 1961 described an algorithm for d e coding BCH codes, but this was cumbersome compared with the majority-logic methods of Massey and others. Thus the search began for codes which are easily decoded with comparatively simple apparatus. The finite geometry codes which were described by Rudolph in a 1964 thesis were examples of codes which are easily decoded 58 by a small number of steps of majority logic. The simplicial codes of Saltzer are even better in this respect, since they can be decoded by a single step of majority logic, but are rather inefficient . The applications of coding theory have changed over the years, as well. The first computers were huge circuits of relays, which were unreliable and prone to errors. Error correcting codes were required to minimise the possibility of incorrect results. As vacuum tubes and later transistorised circuits made computers more reliable, the need for sophisticated and powerful codes in the computer world diminished. Other used presented themselves however, for example the control systems of unmanned space craft. Because of the difficulty of sending and receiving messages in this case, · very powerful codes were required. Other uses were found in transmission lines and telephone exchanges. The codes considered in this dissertation have, for the most part, been block codes for use on the binary symmetric channel. There are, however, several other applications, such as codes for use on an erasure channel, where bits are corrupted so as to be unrecognizable, rather than changed. There are also codes for burst-error correction, where chennel noise is not randomly distributed, but occurs in "bursts" a few bits long. Certain cyclic codes are of application in these cases. The theory of error correcting codes has risen from virtual non-existence in 1950 to a major and sophisticated part of communication theory. Judging from the articles in journals, it promises to be the subject of a great deal of research for some years to come.
- Full Text:
- Date Issued: 1978
- Authors: Booth, Geoffrey L
- Date: 1978
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:20967 , http://hdl.handle.net/10962/5718
- Description: From Conclusion: The study of error-correcting codes is now approximately 25 years old. The first known publication on the subject was in 1949 by M. Golay, who later did much research into the subject of perfect codes. It has been recently established that all the perfect codes are known. R.W. Hamming presented his perfect single-error correcting codes in 1950, in ~n article in the Bell System Technical Journal. These codes turned out to be a special case of the powerful Bose-Chaudhuri codes which were discovered around 1960. Various work has been done on the theory of minimal redundancy of codes for a given error-correcting performance, by Plotkin, Gilbert, Varshamov and others, between 1950 and 1960. The binary BCH codes were found to be so close to the theoretical bounds that, to date, no better codes have been discovered. Although the BCH codes are extremely efficient in terms of ratio of information to check digits, they are not easily, decoded with a minimal amount of apparatus. Petersen in 1961 described an algorithm for d e coding BCH codes, but this was cumbersome compared with the majority-logic methods of Massey and others. Thus the search began for codes which are easily decoded with comparatively simple apparatus. The finite geometry codes which were described by Rudolph in a 1964 thesis were examples of codes which are easily decoded 58 by a small number of steps of majority logic. The simplicial codes of Saltzer are even better in this respect, since they can be decoded by a single step of majority logic, but are rather inefficient . The applications of coding theory have changed over the years, as well. The first computers were huge circuits of relays, which were unreliable and prone to errors. Error correcting codes were required to minimise the possibility of incorrect results. As vacuum tubes and later transistorised circuits made computers more reliable, the need for sophisticated and powerful codes in the computer world diminished. Other used presented themselves however, for example the control systems of unmanned space craft. Because of the difficulty of sending and receiving messages in this case, · very powerful codes were required. Other uses were found in transmission lines and telephone exchanges. The codes considered in this dissertation have, for the most part, been block codes for use on the binary symmetric channel. There are, however, several other applications, such as codes for use on an erasure channel, where bits are corrupted so as to be unrecognizable, rather than changed. There are also codes for burst-error correction, where chennel noise is not randomly distributed, but occurs in "bursts" a few bits long. Certain cyclic codes are of application in these cases. The theory of error correcting codes has risen from virtual non-existence in 1950 to a major and sophisticated part of communication theory. Judging from the articles in journals, it promises to be the subject of a great deal of research for some years to come.
- Full Text:
- Date Issued: 1978
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