The role of the sandprawn, Callichirus kraussi, as an ecosystem engineer in a temporarily open/closed Eastern Cape estuary, South Africa
- Authors: Njozela, Cuma
- Date: 2013
- Subjects: Estuarine biology -- South Africa -- Eastern Cape , Decapoda (Crustacea) -- South Africa -- Eastern Cape , Biotic communities -- South Africa -- Eastern Cape , Bioenergetics -- South Africa -- Eastern Cape , Shrimps -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5583 , http://hdl.handle.net/10962/d1001539 , Estuarine biology -- South Africa -- Eastern Cape , Decapoda (Crustacea) -- South Africa -- Eastern Cape , Biotic communities -- South Africa -- Eastern Cape , Bioenergetics -- South Africa -- Eastern Cape , Shrimps -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape
- Description: The role of the sandprawn, Callichirus (=Callianassa) kraussi (Stebbing), as an ecosystem engineer was assessed in the lower reach of the temporarily open/closed Kasouga Estuary situated along the Eastern Cape coastline of southern Africa over the period April 2010 to June 2011. The study comprised two distinct components, a field study and a caging experiment. The field study assessed the correlation between sand prawn densities and selected physico-chemical (organic content of the sediment and bioturbation) and biological (microphytobenthic algal concentrations and macrobenthic abundance and biomass) variables in 50 quadrants in the lower reach of the estuary. Densities of the sand prawn within the quadrants ranged from 0 to 156 ind m⁻² (mean = 37 ind m⁻²). There were no significant correlations between the densities of the sandprawn and the estimates of the organic content of the sediment and the abundance and biomass of the macrofauna (P > 0.05 in all cases). Numerical analyses failed to identify any effect of the sandprawn density on the macrofaunal community structure. The rate of bioturbation was, however, strongly correlated to the sand prawn density. Similarly, the microphytobenthic alga concentrations were significantly negatively correlated to the sand prawn densities ((P < 0.05). The absence of any distinct impact of the sandprawn on the macrobenthic community structure appeared to be related to their low densities in the lower reach of the estuary during the study. To better understand the role of the sandprawn as an ecosystem engineer, a caging experiment was conducted using inclusion and exclusion treatments (n= 5 for each treatment). Densities of the sandprawn in the inclusion treatments (80 ind m⁻²) were in the range of the natural densities within the estuary. The experiment was conducted over a period of 18 weeks in the lower reach of the estuary during summer. The presence of the sandprawn, C kraussi, contributed to a significant decrease in the microphytobenthic algal concentrations and the abundance and biomass of the macrofauna (P < 0.05 in all cases). The decrease in the microphytobenthic algal concentrations in the presence of the sandprawn appeared to be related to the res-suspension of the sediments (bioturbation) generated by the burrowing and feeding activities of the sandprawn. The observed decrease in macrofaunal abundances and biomass in the inclusion treatments appeared to be mediated by both the decreased food availability (mainly the microphytobenthic algae) and the burial of organisms within the sediments. Numerical analysis indicated that the sandprawn did, however, not contribute to a change in the species composition of the macrofauna. Results of the current study indicate that C.kraussi plays an important role in structuring the invertebrate community and energy flow within temporarily/open closed Kasouga Estuary.
- Full Text:
- Date Issued: 2013
- Authors: Njozela, Cuma
- Date: 2013
- Subjects: Estuarine biology -- South Africa -- Eastern Cape , Decapoda (Crustacea) -- South Africa -- Eastern Cape , Biotic communities -- South Africa -- Eastern Cape , Bioenergetics -- South Africa -- Eastern Cape , Shrimps -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5583 , http://hdl.handle.net/10962/d1001539 , Estuarine biology -- South Africa -- Eastern Cape , Decapoda (Crustacea) -- South Africa -- Eastern Cape , Biotic communities -- South Africa -- Eastern Cape , Bioenergetics -- South Africa -- Eastern Cape , Shrimps -- South Africa -- Eastern Cape , Estuarine ecology -- South Africa -- Eastern Cape
- Description: The role of the sandprawn, Callichirus (=Callianassa) kraussi (Stebbing), as an ecosystem engineer was assessed in the lower reach of the temporarily open/closed Kasouga Estuary situated along the Eastern Cape coastline of southern Africa over the period April 2010 to June 2011. The study comprised two distinct components, a field study and a caging experiment. The field study assessed the correlation between sand prawn densities and selected physico-chemical (organic content of the sediment and bioturbation) and biological (microphytobenthic algal concentrations and macrobenthic abundance and biomass) variables in 50 quadrants in the lower reach of the estuary. Densities of the sand prawn within the quadrants ranged from 0 to 156 ind m⁻² (mean = 37 ind m⁻²). There were no significant correlations between the densities of the sandprawn and the estimates of the organic content of the sediment and the abundance and biomass of the macrofauna (P > 0.05 in all cases). Numerical analyses failed to identify any effect of the sandprawn density on the macrofaunal community structure. The rate of bioturbation was, however, strongly correlated to the sand prawn density. Similarly, the microphytobenthic alga concentrations were significantly negatively correlated to the sand prawn densities ((P < 0.05). The absence of any distinct impact of the sandprawn on the macrobenthic community structure appeared to be related to their low densities in the lower reach of the estuary during the study. To better understand the role of the sandprawn as an ecosystem engineer, a caging experiment was conducted using inclusion and exclusion treatments (n= 5 for each treatment). Densities of the sandprawn in the inclusion treatments (80 ind m⁻²) were in the range of the natural densities within the estuary. The experiment was conducted over a period of 18 weeks in the lower reach of the estuary during summer. The presence of the sandprawn, C kraussi, contributed to a significant decrease in the microphytobenthic algal concentrations and the abundance and biomass of the macrofauna (P < 0.05 in all cases). The decrease in the microphytobenthic algal concentrations in the presence of the sandprawn appeared to be related to the res-suspension of the sediments (bioturbation) generated by the burrowing and feeding activities of the sandprawn. The observed decrease in macrofaunal abundances and biomass in the inclusion treatments appeared to be mediated by both the decreased food availability (mainly the microphytobenthic algae) and the burial of organisms within the sediments. Numerical analysis indicated that the sandprawn did, however, not contribute to a change in the species composition of the macrofauna. Results of the current study indicate that C.kraussi plays an important role in structuring the invertebrate community and energy flow within temporarily/open closed Kasouga Estuary.
- Full Text:
- Date Issued: 2013
The Rotterdam Rules : a South African perspective
- Authors: Gordon, Goscelin Lucy
- Date: 2013
- Subjects: Rotterdam Rules (2008) , Contracts, Maritime , Maritime law , Maritime law -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3662 , http://hdl.handle.net/10962/d1001865 , Rotterdam Rules (2008) , Contracts, Maritime , Maritime law , Maritime law -- South Africa
- Description: The objective of this paper is to investigate the Rotterdam Rules, and to ascertain whether South Africa should accede to or ratify them. In order to accomplish this, South Africa's current maritime transport regime will be examined, and existing "problem areas" will be identified. This will be followed by a comparative analysis between the Rotterdam Rules and the Hague-Visby Rules, which South Africa applies as part of national law to regulate the carriage of goods by sea. As a new maritime Convention, the Rotterdam Rules have attracted widespread criticism and support, and whether such is justified will also be considered. Finally potential considerations South Africa should take into account in electing whether or not to accede or ratify the Rules have been assessed from a political, economic, social, technological, legal and environmental standpoint as at 31 December 2011
- Full Text:
- Date Issued: 2013
- Authors: Gordon, Goscelin Lucy
- Date: 2013
- Subjects: Rotterdam Rules (2008) , Contracts, Maritime , Maritime law , Maritime law -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3662 , http://hdl.handle.net/10962/d1001865 , Rotterdam Rules (2008) , Contracts, Maritime , Maritime law , Maritime law -- South Africa
- Description: The objective of this paper is to investigate the Rotterdam Rules, and to ascertain whether South Africa should accede to or ratify them. In order to accomplish this, South Africa's current maritime transport regime will be examined, and existing "problem areas" will be identified. This will be followed by a comparative analysis between the Rotterdam Rules and the Hague-Visby Rules, which South Africa applies as part of national law to regulate the carriage of goods by sea. As a new maritime Convention, the Rotterdam Rules have attracted widespread criticism and support, and whether such is justified will also be considered. Finally potential considerations South Africa should take into account in electing whether or not to accede or ratify the Rules have been assessed from a political, economic, social, technological, legal and environmental standpoint as at 31 December 2011
- Full Text:
- Date Issued: 2013
The screening and characterisation of compounds for modulators of heat shock protein (Hsp90) in a breast cancer cell model
- Authors: Moyo, Buhle
- Date: 2013 , 2013-07-18
- Subjects: Heat shock proteins Breast -- Cancer Breast -- Cancer -- Chemotherapy Breast -- Cancer -- Treatment Cancer cells Naphthoquinone PQQ (Biochemistry)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4060 , http://hdl.handle.net/10962/d1004129
- Description: Breast cancer is a leading cause of cancer death in Africa. Hsp90 has been identified as a target for anti-cancer treatments as its inhibition results in the disruption and ubiquitin–proteasome degradation of activated oncoproteins. Currently, there are no US Food and Drug Administration approved Hsp90 inhibitor drugs and existing Hsp90 inhibitors such as geldanamycin and novobiocin are hepatotoxic and display a low affinity for Hsp90, respectively. Therefore, there is a need for the development of Hsp90 inhibitors with improved inhibitory properties. In this study twelve natural compounds bearing a quinone nucleus were screened and characterised for the modulation of Hsp90. The compounds analysed formed three series; the sargaquinoic acid (SQA), naphthoquinone, and pyrroloiminoquinone alkaloid series. Certain compounds exhibited half maximal inhibitory concentrations of between 3.32 μM and 12.4 μM, while others showed no antiproliferative activity at concentrations of up to 500 μM in the MDA-MB-231 breast adenocarcinoma cell line. Immunofluorescence and Western analyses indicated that the modulation of Hsp90 and partner proteins by SQA was more similar to that of novobiocin. Isothermal titration calorimetry analyses suggested that SQA interacted with Hsp90β with a low affinity, and saturation-transfer difference nuclear magnetic resonance confirmed that this interaction with Hsp90β occurred through the methyl moiety bound to 1, 4 benzoquinone of SQA. Pulldown assays indicated SQA disrupted the association between Hsp90 and Hop dose-dependently, more similarly to novobiocin. Immunofluorescence and Western analyses performed on naphthoquinone and pyrroloiminoquinone alkaloid compounds indicated modulation of Hsp90 and Hsp90 partner proteins by the compounds. Naphthoquinone compounds were prioritised for analysis for binding to Hsp90β over the pyrroloiminoquinone alkaloid compounds. Lapachol interacted with Hsp90β with a low affinity however; this interaction was thought to be too weak to disrupt the association of Hsp90 and Hop. The remaining naphthoquinone compounds showed no interaction with Hsp90β, thus allowing the determination of a preliminary structure-activity relationship for these compounds. To the best of our knowledge, this is the first study to describe a systematic subcellular analysis of the effects of geldanamycin and novobiocin in comparison to sargaquinoic acid and compounds of the naphthoquinone and pyrroloquinoline scaffold on Hsp90 and its partner proteins. , Microsoft� Word 2010 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
- Authors: Moyo, Buhle
- Date: 2013 , 2013-07-18
- Subjects: Heat shock proteins Breast -- Cancer Breast -- Cancer -- Chemotherapy Breast -- Cancer -- Treatment Cancer cells Naphthoquinone PQQ (Biochemistry)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4060 , http://hdl.handle.net/10962/d1004129
- Description: Breast cancer is a leading cause of cancer death in Africa. Hsp90 has been identified as a target for anti-cancer treatments as its inhibition results in the disruption and ubiquitin–proteasome degradation of activated oncoproteins. Currently, there are no US Food and Drug Administration approved Hsp90 inhibitor drugs and existing Hsp90 inhibitors such as geldanamycin and novobiocin are hepatotoxic and display a low affinity for Hsp90, respectively. Therefore, there is a need for the development of Hsp90 inhibitors with improved inhibitory properties. In this study twelve natural compounds bearing a quinone nucleus were screened and characterised for the modulation of Hsp90. The compounds analysed formed three series; the sargaquinoic acid (SQA), naphthoquinone, and pyrroloiminoquinone alkaloid series. Certain compounds exhibited half maximal inhibitory concentrations of between 3.32 μM and 12.4 μM, while others showed no antiproliferative activity at concentrations of up to 500 μM in the MDA-MB-231 breast adenocarcinoma cell line. Immunofluorescence and Western analyses indicated that the modulation of Hsp90 and partner proteins by SQA was more similar to that of novobiocin. Isothermal titration calorimetry analyses suggested that SQA interacted with Hsp90β with a low affinity, and saturation-transfer difference nuclear magnetic resonance confirmed that this interaction with Hsp90β occurred through the methyl moiety bound to 1, 4 benzoquinone of SQA. Pulldown assays indicated SQA disrupted the association between Hsp90 and Hop dose-dependently, more similarly to novobiocin. Immunofluorescence and Western analyses performed on naphthoquinone and pyrroloiminoquinone alkaloid compounds indicated modulation of Hsp90 and Hsp90 partner proteins by the compounds. Naphthoquinone compounds were prioritised for analysis for binding to Hsp90β over the pyrroloiminoquinone alkaloid compounds. Lapachol interacted with Hsp90β with a low affinity however; this interaction was thought to be too weak to disrupt the association of Hsp90 and Hop. The remaining naphthoquinone compounds showed no interaction with Hsp90β, thus allowing the determination of a preliminary structure-activity relationship for these compounds. To the best of our knowledge, this is the first study to describe a systematic subcellular analysis of the effects of geldanamycin and novobiocin in comparison to sargaquinoic acid and compounds of the naphthoquinone and pyrroloquinoline scaffold on Hsp90 and its partner proteins. , Microsoft� Word 2010 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
The SKA's the limit : on the nature of faint radio sources
- Authors: McAlpine, Kim
- Date: 2013 , 2012-09-14
- Subjects: Radio telescopes -- South Africa Radio astronomy -- South Africa Square Kilometer Array (Spacecraft)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5504 , http://hdl.handle.net/10962/d1007271
- Description: From abstract: Within the next few years a large number of new and vastly more sensitive radio astronomy facilities are scheduled to come online. These new facilities will map large areas of the sky to unprecedented depths and transform radio astronomy into the leading technique for investigating the complex processes which govern the formation and evolution of galaxies. This thesis combines multi-wavelength techniques, highly relevant to future deep radio surveys, to study the evolution and properties of faint radio sources. , TeX , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
- Authors: McAlpine, Kim
- Date: 2013 , 2012-09-14
- Subjects: Radio telescopes -- South Africa Radio astronomy -- South Africa Square Kilometer Array (Spacecraft)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5504 , http://hdl.handle.net/10962/d1007271
- Description: From abstract: Within the next few years a large number of new and vastly more sensitive radio astronomy facilities are scheduled to come online. These new facilities will map large areas of the sky to unprecedented depths and transform radio astronomy into the leading technique for investigating the complex processes which govern the formation and evolution of galaxies. This thesis combines multi-wavelength techniques, highly relevant to future deep radio surveys, to study the evolution and properties of faint radio sources. , TeX , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
The talisman
- Authors: Reed, Graham Conan
- Date: 2013
- Subjects: Fiction , Short stories , English , South Africa , Creative writing (Higher education) , Short stories, South African (English) -- 21st century , South African fiction (English) -- 21st century , English language -- Writing
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:5967 , http://hdl.handle.net/10962/d1001817
- Description: The Talisman is an adventure story set in a future where much of today's cultural memory and technology has been lost. Following a hunting accident, a young man named Forest survives a life-threatening wound and embarks on a quest for knowledge. Rising sea levels, bands of marauders, wild animals and the perils of survival in the broken world are not the only problems facing the survivors. The nature of the collapse of the society, what triggered it and its subsequent unfolding, bequeaths an existential quandary upon them that only Forest, and a rare text as old as the earth itself, can unravel
- Full Text:
- Date Issued: 2013
- Authors: Reed, Graham Conan
- Date: 2013
- Subjects: Fiction , Short stories , English , South Africa , Creative writing (Higher education) , Short stories, South African (English) -- 21st century , South African fiction (English) -- 21st century , English language -- Writing
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:5967 , http://hdl.handle.net/10962/d1001817
- Description: The Talisman is an adventure story set in a future where much of today's cultural memory and technology has been lost. Following a hunting accident, a young man named Forest survives a life-threatening wound and embarks on a quest for knowledge. Rising sea levels, bands of marauders, wild animals and the perils of survival in the broken world are not the only problems facing the survivors. The nature of the collapse of the society, what triggered it and its subsequent unfolding, bequeaths an existential quandary upon them that only Forest, and a rare text as old as the earth itself, can unravel
- Full Text:
- Date Issued: 2013
The tax treatment of receipts and accruals arising from equity option contracts
- Authors: Doidge, Stephen
- Date: 2013
- Subjects: Derivative securities Options (Finance) Swaps (Finance) Income tax -- Law and legislation -- South Africa Taxation -- South Africa Futures
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:903 , http://hdl.handle.net/10962/d1007921
- Description: In this thesis the tax treatment of equity option contracts is examined. The writer gives an overview of the derivatives market in general and discusses the nature and effect of equity options in detail. Limited amendments have been made to the South African Income Tax Act No 58 of 1962 ('the Act') since the emergence of derivative instruments and at present only three types of derivative instruments are recognised: forward exchange and option contracts relating to forward exchange, interest rate swaps based on notional capital amounts and option contracts. Other than section 241 of the Act which deems all receipts and accruals from foreign exchange contracts to be income, the other sections dealing with derivatives do not concern themselves with capital or revenue classification. Accordingly, the classification of receipts and accruals arising from an equity option transaction is generally governed by the ordinary principles of South African tax law with the added problem of there being limited South African case law applying these general prinCiples to such transactions. The research undertaken in this thesis results in the establishment of a framework designed to determine the classification as revenue or capital the receipts and accruals arising from equity option contracts. Speculating, trading and investing in equity options is examined with regard to the general principles of South African tax and available case law. Hedging transactions are analysed with specific reference to their exact nature as well as general tax principles and available case law. The analogy of Krugerrands is used to draw parallels with the tax treatment of receipts and accruals arising from equity options used for hedging purposes. Once the theoretical framework has been established for revenue or capital classification, the actual tax treatment of both revenue and capital receipts is examined with reference to the Act and issues such as the gross income definition, the general deduction formula, trading stock and timing provisions are analysed and applied to receipts and accruals arising from equity option transactions. The thesis concludes with a summary of the findings and recommendations are made based on the research conducted.
- Full Text:
- Date Issued: 2013
- Authors: Doidge, Stephen
- Date: 2013
- Subjects: Derivative securities Options (Finance) Swaps (Finance) Income tax -- Law and legislation -- South Africa Taxation -- South Africa Futures
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:903 , http://hdl.handle.net/10962/d1007921
- Description: In this thesis the tax treatment of equity option contracts is examined. The writer gives an overview of the derivatives market in general and discusses the nature and effect of equity options in detail. Limited amendments have been made to the South African Income Tax Act No 58 of 1962 ('the Act') since the emergence of derivative instruments and at present only three types of derivative instruments are recognised: forward exchange and option contracts relating to forward exchange, interest rate swaps based on notional capital amounts and option contracts. Other than section 241 of the Act which deems all receipts and accruals from foreign exchange contracts to be income, the other sections dealing with derivatives do not concern themselves with capital or revenue classification. Accordingly, the classification of receipts and accruals arising from an equity option transaction is generally governed by the ordinary principles of South African tax law with the added problem of there being limited South African case law applying these general prinCiples to such transactions. The research undertaken in this thesis results in the establishment of a framework designed to determine the classification as revenue or capital the receipts and accruals arising from equity option contracts. Speculating, trading and investing in equity options is examined with regard to the general principles of South African tax and available case law. Hedging transactions are analysed with specific reference to their exact nature as well as general tax principles and available case law. The analogy of Krugerrands is used to draw parallels with the tax treatment of receipts and accruals arising from equity options used for hedging purposes. Once the theoretical framework has been established for revenue or capital classification, the actual tax treatment of both revenue and capital receipts is examined with reference to the Act and issues such as the gross income definition, the general deduction formula, trading stock and timing provisions are analysed and applied to receipts and accruals arising from equity option transactions. The thesis concludes with a summary of the findings and recommendations are made based on the research conducted.
- Full Text:
- Date Issued: 2013
The use of tax incentive measure in conjunction with carbon taxes to reduce greenhouse gas emissions and achieve economic growth: a comparative study with lessons for South Africa
- Authors: Poole, Richard
- Date: 2013
- Subjects: Elasticity (Economics) , Substitution (Economics) , Carbon taxes , Carbon taxes -- South Africa , Greenhouse gas mitigation , Greenhouse gas mitigation--South Africa , United Nations Framework Convention on Climate Change -- (1992). Protocols, etc. -- 1997 Dec. 11 , Kyoto Protocol , Substitution elasticity
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:875 , http://hdl.handle.net/10962/d1001607 , Elasticity (Economics) , Substitution (Economics) , Carbon taxes , Carbon taxes -- South Africa , Greenhouse gas mitigation , Greenhouse gas mitigation--South Africa , United Nations Framework Convention on Climate Change -- (1992). Protocols, etc. -- 1997 Dec. 11
- Description: In 1997 industrialized nations, the Third Conference of the Parties to the United Nations Framework Convention on Climate Change, met in Kyoto, Japan to sign a treaty (the “Kyoto Protocol”) in terms of which industrialized nations would be required to reduce their greenhouse gas emission by at least five percent below 1990 levels by the end of the “first commitment period” 2008-2012. South Africa is not regarded as an industrialized nation, but nonetheless acceded to the Kyoto Protocol in 2002. The literature reviewed in the present research reveals that, although idealistic, the Kyoto Protocol has been problematic. Fourteen meetings of the Conference of Parties to the Kyoto Protocol between 1997 and 2011 have achieved little more than to repeatedly defer and redefine Kyoto obligations. This research was undertaken to document the existing environmental taxation policies employed in selected international jurisdictions with a view to providing a framework for environmental tax policy formation in South Africa to assist this country in meeting its “greenhouse gas” emission targets, while at the same time promoting economic growth. A doctrinal research methodology was adopted in this study as it mainly analysed and interpreted legislation and policy documents and therefore the approach was qualitative in nature. An extensive literature survey was performed to document the various environmental policies that have been legislated in the selected jurisdictions. Comparisons were drawn with proposed tax policy measures for South Africa. The literature indicates that in the selected international jurisdictions carbon taxes achieved less-than-optimal results, largely due to political and industry-competitive agendas. With South Africa planning to introduce a carbon tax, it is submitted that the implementation of a carbon tax regime in isolation will be counter-productive, given South Africa’s economic profile. On the basis of the literature reviewed, it was concluded that South Africa should consider “recycling” carbon tax revenues within the economy to fund a broad-based tax incentive regime that will stimulate the change to non-carbon energy whilst promoting growth through sustainable development
- Full Text:
- Date Issued: 2013
- Authors: Poole, Richard
- Date: 2013
- Subjects: Elasticity (Economics) , Substitution (Economics) , Carbon taxes , Carbon taxes -- South Africa , Greenhouse gas mitigation , Greenhouse gas mitigation--South Africa , United Nations Framework Convention on Climate Change -- (1992). Protocols, etc. -- 1997 Dec. 11 , Kyoto Protocol , Substitution elasticity
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:875 , http://hdl.handle.net/10962/d1001607 , Elasticity (Economics) , Substitution (Economics) , Carbon taxes , Carbon taxes -- South Africa , Greenhouse gas mitigation , Greenhouse gas mitigation--South Africa , United Nations Framework Convention on Climate Change -- (1992). Protocols, etc. -- 1997 Dec. 11
- Description: In 1997 industrialized nations, the Third Conference of the Parties to the United Nations Framework Convention on Climate Change, met in Kyoto, Japan to sign a treaty (the “Kyoto Protocol”) in terms of which industrialized nations would be required to reduce their greenhouse gas emission by at least five percent below 1990 levels by the end of the “first commitment period” 2008-2012. South Africa is not regarded as an industrialized nation, but nonetheless acceded to the Kyoto Protocol in 2002. The literature reviewed in the present research reveals that, although idealistic, the Kyoto Protocol has been problematic. Fourteen meetings of the Conference of Parties to the Kyoto Protocol between 1997 and 2011 have achieved little more than to repeatedly defer and redefine Kyoto obligations. This research was undertaken to document the existing environmental taxation policies employed in selected international jurisdictions with a view to providing a framework for environmental tax policy formation in South Africa to assist this country in meeting its “greenhouse gas” emission targets, while at the same time promoting economic growth. A doctrinal research methodology was adopted in this study as it mainly analysed and interpreted legislation and policy documents and therefore the approach was qualitative in nature. An extensive literature survey was performed to document the various environmental policies that have been legislated in the selected jurisdictions. Comparisons were drawn with proposed tax policy measures for South Africa. The literature indicates that in the selected international jurisdictions carbon taxes achieved less-than-optimal results, largely due to political and industry-competitive agendas. With South Africa planning to introduce a carbon tax, it is submitted that the implementation of a carbon tax regime in isolation will be counter-productive, given South Africa’s economic profile. On the basis of the literature reviewed, it was concluded that South Africa should consider “recycling” carbon tax revenues within the economy to fund a broad-based tax incentive regime that will stimulate the change to non-carbon energy whilst promoting growth through sustainable development
- Full Text:
- Date Issued: 2013
The value of non-native fish species : a study of recreational angling in the Amathole district
- Authors: Kinghorn, James Wolmarans
- Date: 2013
- Subjects: Fishing -- Economic aspects -- South Africa -- Eastern Cape Introduced fishes -- Economic aspects -- South Africa -- Eastern Cape Fisheries -- South Africa -- Eastern Cape , Non-native fish species , Recreational angling , Amathole district
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:930 , http://hdl.handle.net/10962/d1001456
- Description: Experience has shown that effective fisheries governance requires a sound understanding of fisheries as systems incorporating both ecological and human dimensions. The Ecosystem Approach to Fisheries requires that the human components of these systems be considered when developing management and governance frameworks. While the potential for inland fisheries to contribute towards societal welfare and the development of rural livelihoods is becoming increasingly apparent, developing South African inland fisheries requires a careful consideration of both their positive and negative impacts, given that they revolve mainly around five of the world‟s top 100 invasive species. This thesis aimed to explore the value of inland recreational fisheries to rural livelihoods in the Amathole District of South Africa, to the regional economy, and to anglers themselves. Three methods were used to isolate this value. Economic impact analysis was used to estimate the combined total economic impact of the 2011 Divisional Tournament (n=31) and the 2012 Amatola Bass Classic (n=100) on the regional economy of the Amathole District, estimated to be R106 625. The travel cost method was applied to data from the 2012 Amatola Bass Classic in order to estimate the social welfare generated by this tournament. The Negative Binomial model, corrected for truncation and endogenous stratification, estimated this value at R 1 960 090. The sustainable livelihoods framework was used to conduct a broad-based analysis of the value of Amatola Wild Trout, the firm which constitutes the fishery surrounding the rural village of Cata. It was found that the fishery had been responsible for a modest pecuniary impact on the community of Cata within its first two years of establishment, although significant improvements in human capital were found to have resulted from the development of the fishery. These results provide insights into the economic dimension of fisheries in the Amathole District, and will prove useful when weighing up the positive and negative impacts of non-native fish species, particularly when informing decisions regarding their potential eradication.
- Full Text:
- Date Issued: 2013
- Authors: Kinghorn, James Wolmarans
- Date: 2013
- Subjects: Fishing -- Economic aspects -- South Africa -- Eastern Cape Introduced fishes -- Economic aspects -- South Africa -- Eastern Cape Fisheries -- South Africa -- Eastern Cape , Non-native fish species , Recreational angling , Amathole district
- Language: English
- Type: Thesis , Masters , MEcon
- Identifier: vital:930 , http://hdl.handle.net/10962/d1001456
- Description: Experience has shown that effective fisheries governance requires a sound understanding of fisheries as systems incorporating both ecological and human dimensions. The Ecosystem Approach to Fisheries requires that the human components of these systems be considered when developing management and governance frameworks. While the potential for inland fisheries to contribute towards societal welfare and the development of rural livelihoods is becoming increasingly apparent, developing South African inland fisheries requires a careful consideration of both their positive and negative impacts, given that they revolve mainly around five of the world‟s top 100 invasive species. This thesis aimed to explore the value of inland recreational fisheries to rural livelihoods in the Amathole District of South Africa, to the regional economy, and to anglers themselves. Three methods were used to isolate this value. Economic impact analysis was used to estimate the combined total economic impact of the 2011 Divisional Tournament (n=31) and the 2012 Amatola Bass Classic (n=100) on the regional economy of the Amathole District, estimated to be R106 625. The travel cost method was applied to data from the 2012 Amatola Bass Classic in order to estimate the social welfare generated by this tournament. The Negative Binomial model, corrected for truncation and endogenous stratification, estimated this value at R 1 960 090. The sustainable livelihoods framework was used to conduct a broad-based analysis of the value of Amatola Wild Trout, the firm which constitutes the fishery surrounding the rural village of Cata. It was found that the fishery had been responsible for a modest pecuniary impact on the community of Cata within its first two years of establishment, although significant improvements in human capital were found to have resulted from the development of the fishery. These results provide insights into the economic dimension of fisheries in the Amathole District, and will prove useful when weighing up the positive and negative impacts of non-native fish species, particularly when informing decisions regarding their potential eradication.
- Full Text:
- Date Issued: 2013
The violence of language : contemporary hate speech and the suitability of legal measures regulating hate speech in South Africa
- Authors: Janse van Rensburg, Leanne
- Date: 2013
- Subjects: Hate speech -- South Africa , Hate speech -- Law and legislation -- South Africa , Racism in language , Freedom of speech -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3663 , http://hdl.handle.net/10962/d1001866 , Hate speech -- South Africa , Hate speech -- Law and legislation -- South Africa , Racism in language , Freedom of speech -- South Africa
- Description: This thesis unites law and social science so as to give a comprehensive account of the phenomenon of racial hate speech in South Africa as an obstacle to transformation. Hate speech is presented as a form of violent language and an affront to the constitutional rights of freedom of speech, equality and dignity. To establish the nature of hate speech, the fluid quality of language is explored so as to show how language can be manipulated, on the one hand, as a means to harm, and employed, on the other hand, as a tool to heal and reconcile. This double gesture is illustrated through the South African linguistic experience of past hate and segregation and the current transformation agenda. It is through this prism that hate speech regulation is discussed as an uneasy fit in a country where freedom of expression is constitutionally protected and where language plays an important role in bringing about reconciliation, and yet words are still being employed to divide and dehumanise. This reality necessitates a clearly articulated stance on the regulation of language. The thesis accordingly interrogates the current legal standards in relation to hate speech with reference to international law that binds South Africa and the constitutional standard set for the regulation of language and the prohibition of hate speech. Thereafter, the current and proposed legislative prohibitions on hate speech, the residual common law provisions governing expression and the regulation of language in the media are outlined and analysed. These legal frameworks are explored in terms of their content and their application in various fora so as to ascertain what the South African approach to hate speech prohibition is, whether it is consistent and, ultimately if it is indeed suitable to the South African experience and the realities of language. This thesis concludes that contemporary hate speech measures lack a coherent understanding of what hate speech entails and a general inconsistency in approach as well as application is found in the treatment of hate speech complaints in South Africa. This is explained through the fallibility of language as a medium to regulate expression and solutions are offered to not only taper current and proposed hate speech provisions but to also consider alternative forms of resolving hate speech complaints
- Full Text:
- Date Issued: 2013
- Authors: Janse van Rensburg, Leanne
- Date: 2013
- Subjects: Hate speech -- South Africa , Hate speech -- Law and legislation -- South Africa , Racism in language , Freedom of speech -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:3663 , http://hdl.handle.net/10962/d1001866 , Hate speech -- South Africa , Hate speech -- Law and legislation -- South Africa , Racism in language , Freedom of speech -- South Africa
- Description: This thesis unites law and social science so as to give a comprehensive account of the phenomenon of racial hate speech in South Africa as an obstacle to transformation. Hate speech is presented as a form of violent language and an affront to the constitutional rights of freedom of speech, equality and dignity. To establish the nature of hate speech, the fluid quality of language is explored so as to show how language can be manipulated, on the one hand, as a means to harm, and employed, on the other hand, as a tool to heal and reconcile. This double gesture is illustrated through the South African linguistic experience of past hate and segregation and the current transformation agenda. It is through this prism that hate speech regulation is discussed as an uneasy fit in a country where freedom of expression is constitutionally protected and where language plays an important role in bringing about reconciliation, and yet words are still being employed to divide and dehumanise. This reality necessitates a clearly articulated stance on the regulation of language. The thesis accordingly interrogates the current legal standards in relation to hate speech with reference to international law that binds South Africa and the constitutional standard set for the regulation of language and the prohibition of hate speech. Thereafter, the current and proposed legislative prohibitions on hate speech, the residual common law provisions governing expression and the regulation of language in the media are outlined and analysed. These legal frameworks are explored in terms of their content and their application in various fora so as to ascertain what the South African approach to hate speech prohibition is, whether it is consistent and, ultimately if it is indeed suitable to the South African experience and the realities of language. This thesis concludes that contemporary hate speech measures lack a coherent understanding of what hate speech entails and a general inconsistency in approach as well as application is found in the treatment of hate speech complaints in South Africa. This is explained through the fallibility of language as a medium to regulate expression and solutions are offered to not only taper current and proposed hate speech provisions but to also consider alternative forms of resolving hate speech complaints
- Full Text:
- Date Issued: 2013
Towards a cost-efficient & standardised monitoring protocol for subtidal reef fish in the Agulhas ecoregion of South Africa
- Bernard, Anthony Thomas Firth
- Authors: Bernard, Anthony Thomas Firth
- Date: 2013
- Subjects: Reef fishes -- South Africa Reef fishes -- Monitoring--South Africa Fish stock assessment -- South Africa Coastal zone management -- South Africa Fish communities -- South Africa Marine parks and reserves -- South Africa Marine resources conservation -- South Africa Marine biodiversity conservation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5585 , http://hdl.handle.net/10962/d1001674
- Description: Under the growing demand for marine fish resources, and the apparent and expected impacts of global climate change, there is a need to conduct long-term monitoring (LTM) to ensure effective management of resources and conservation of biodiversity. However LTM programmes often suffer from design deficiencies and fail to achieve their objectives. These deficiencies stem from the fact that insufficient consideration is afforded to the design phase, with programmes selecting methods that are not suitable to address the objectives, or are not cost-efficient, compromising the sustainability of the LTM. To facilitate the establishment of LTM programmes along the southern coast of South Africa, background research needed to be conducted to identify which methods were most appropriate for LTM of reef fish. This study presents a detailed field-based assessment of the suitability and cost-efficiency of monitoring methods for long-term monitoring of reef fish in the Agulhas Ecoregion of South Africa. The approach adopted to identify the method, or suite of methods most suited for LTM, involved (i) the selection of methods considered suitable for LTM, (ii) the individual assessment and optimisation of method performance, and (iii) the comparative assessment of the fish community sampled by the different methods. The most suited method(s) were then identified as those that provide the most comprehensive assessment of the fish community and had the highest cost-efficiency. The research was conducted between January 2008 and 2011 in the Tsitsikamma and Table Mountain National Park (TNP and TMNP, respectively) marine protected areas (MPAs) within the Agulhas Ecoregion. The methods selected included fish traps (FT), controlled angling (CA), underwater visual census (UVC), remote underwater video (RUV), baited RUV (BRUV) and remotely operated vehicles (ROV). The individual assessment and optimisation was conducted with the FT, UVC, RUV and BRUV methods. The assessment of the FT method aimed to identify the optimal soak time, and whether or not the size of the funnel entrance to the trap affected the catch. The results identified that larger funnel entrances caught more fish and soak times of 80 minutes produced the highest catches per unit effort. However the data were highly variable and the method detected few of the species typical of the region. Fish traps were also associated with high levels of mortality of fish post-release. The assessment of UVC strip transect method involved directly comparing the precision of data collected by researchers and volunteers using a novel double-observer technique (paired-transects). The results showed considerable error in both the volunteers and researchers data, however the researchers produced significantly higher precision data, compared to the volunteers. The distinction between researchers and volunteers was not evident in the data for the dominant species of fish. For all observers, the abundance of a species in the sample had a significant influence on its detectability, with locally scarce or rare species poorly detected. UVC was able to sample the majority of species typical of reefs in the region, however it appeared plagued by observer and detectability biases. The assessments of RUV and BRUV were conducted simultaneously which enabled the assessment of the effect of bait on the observed fish community. In addition the optimal deployment time for both methods to maximise species richness and abundance was determined. The results showed that BRUV, and to a lesser degree RUV, were able to effectively survey the reef fish community for the region with a 50 minute and 35 minute deployment time, respectively. Baited remote underwater video was especially good at detecting the invertebrate and generalist carnivores, and cartilaginous species. On the other hand, RUV was more effective at surveying the microinvertebrate carnivores. Remote underwater video was characterised by higher data variability, compared to BRUV, and was ultimately considered a less cost-efficient monitoring method. Comparative methods assessments were conducted during two field experiments with the FT, UVC and BRUV methods in the TMNP MPA, and the FT, CA, UVC, RUV, BRUV and ROV methods compared in the TNP MPA. The objectives of the comparison were to investigate differences in the fish communities observed with the different methods, and to determine the power of the data to detect an annual 10% growth in the fish populations over a period of five years. The results from the method comparison were in turn used to conduct the cost-benefit analysis to determine the efficiency of the different methods at achieving monitoring objectives requiring population data from multiple trophic and functional groups with the community, and from species of fisheries importance. The results indicated that FT, CA and ROV were ineffective at monitoring the reef fish community, although CA appeared to provide valuable data for the dominant fisheries species. Both CA and FT required minimal initial investment however, the variability in the data translated into high annual monitoring costs, as the required sampling effort was great. The ROV required the highest initial investment and was identified as the least cost-efficient method. Underwater visual census was able to adequately survey the bony fish within the community, however it did not detect the cartilaginous species. Underwater visual census required a large initial investment and was not cost-efficient, as a many samples were required to account for the variability in the data. Remote underwater video provided a comprehensive assessment of the reef fish community, however it too was associated with high levels of variability in the data, compared to BRUV, reducing its cost-efficiency. BRUV provided the most comprehensive assessment of the reef fish community and was associated with the highest cost-efficiency to address the community and fisheries species monitoring objectives. During the course of this research stereo-BRUV has gained considerable support as an effective reef fish monitoring method. Although not tested during this research, stereo-BRUV is preferred to BRUV as it provides accurate data on the size of fish. However, the initial investment of stereo-BRUV is over three times that required for the BRUV. Although it is recommended that a baited video technique be used for LTM in the Agulhas Ecoregion, the choice between BRUV and stereo-BRUV will depend on the specific objectives of the programme and the available budget at the implementing agency.
- Full Text:
- Date Issued: 2013
- Authors: Bernard, Anthony Thomas Firth
- Date: 2013
- Subjects: Reef fishes -- South Africa Reef fishes -- Monitoring--South Africa Fish stock assessment -- South Africa Coastal zone management -- South Africa Fish communities -- South Africa Marine parks and reserves -- South Africa Marine resources conservation -- South Africa Marine biodiversity conservation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5585 , http://hdl.handle.net/10962/d1001674
- Description: Under the growing demand for marine fish resources, and the apparent and expected impacts of global climate change, there is a need to conduct long-term monitoring (LTM) to ensure effective management of resources and conservation of biodiversity. However LTM programmes often suffer from design deficiencies and fail to achieve their objectives. These deficiencies stem from the fact that insufficient consideration is afforded to the design phase, with programmes selecting methods that are not suitable to address the objectives, or are not cost-efficient, compromising the sustainability of the LTM. To facilitate the establishment of LTM programmes along the southern coast of South Africa, background research needed to be conducted to identify which methods were most appropriate for LTM of reef fish. This study presents a detailed field-based assessment of the suitability and cost-efficiency of monitoring methods for long-term monitoring of reef fish in the Agulhas Ecoregion of South Africa. The approach adopted to identify the method, or suite of methods most suited for LTM, involved (i) the selection of methods considered suitable for LTM, (ii) the individual assessment and optimisation of method performance, and (iii) the comparative assessment of the fish community sampled by the different methods. The most suited method(s) were then identified as those that provide the most comprehensive assessment of the fish community and had the highest cost-efficiency. The research was conducted between January 2008 and 2011 in the Tsitsikamma and Table Mountain National Park (TNP and TMNP, respectively) marine protected areas (MPAs) within the Agulhas Ecoregion. The methods selected included fish traps (FT), controlled angling (CA), underwater visual census (UVC), remote underwater video (RUV), baited RUV (BRUV) and remotely operated vehicles (ROV). The individual assessment and optimisation was conducted with the FT, UVC, RUV and BRUV methods. The assessment of the FT method aimed to identify the optimal soak time, and whether or not the size of the funnel entrance to the trap affected the catch. The results identified that larger funnel entrances caught more fish and soak times of 80 minutes produced the highest catches per unit effort. However the data were highly variable and the method detected few of the species typical of the region. Fish traps were also associated with high levels of mortality of fish post-release. The assessment of UVC strip transect method involved directly comparing the precision of data collected by researchers and volunteers using a novel double-observer technique (paired-transects). The results showed considerable error in both the volunteers and researchers data, however the researchers produced significantly higher precision data, compared to the volunteers. The distinction between researchers and volunteers was not evident in the data for the dominant species of fish. For all observers, the abundance of a species in the sample had a significant influence on its detectability, with locally scarce or rare species poorly detected. UVC was able to sample the majority of species typical of reefs in the region, however it appeared plagued by observer and detectability biases. The assessments of RUV and BRUV were conducted simultaneously which enabled the assessment of the effect of bait on the observed fish community. In addition the optimal deployment time for both methods to maximise species richness and abundance was determined. The results showed that BRUV, and to a lesser degree RUV, were able to effectively survey the reef fish community for the region with a 50 minute and 35 minute deployment time, respectively. Baited remote underwater video was especially good at detecting the invertebrate and generalist carnivores, and cartilaginous species. On the other hand, RUV was more effective at surveying the microinvertebrate carnivores. Remote underwater video was characterised by higher data variability, compared to BRUV, and was ultimately considered a less cost-efficient monitoring method. Comparative methods assessments were conducted during two field experiments with the FT, UVC and BRUV methods in the TMNP MPA, and the FT, CA, UVC, RUV, BRUV and ROV methods compared in the TNP MPA. The objectives of the comparison were to investigate differences in the fish communities observed with the different methods, and to determine the power of the data to detect an annual 10% growth in the fish populations over a period of five years. The results from the method comparison were in turn used to conduct the cost-benefit analysis to determine the efficiency of the different methods at achieving monitoring objectives requiring population data from multiple trophic and functional groups with the community, and from species of fisheries importance. The results indicated that FT, CA and ROV were ineffective at monitoring the reef fish community, although CA appeared to provide valuable data for the dominant fisheries species. Both CA and FT required minimal initial investment however, the variability in the data translated into high annual monitoring costs, as the required sampling effort was great. The ROV required the highest initial investment and was identified as the least cost-efficient method. Underwater visual census was able to adequately survey the bony fish within the community, however it did not detect the cartilaginous species. Underwater visual census required a large initial investment and was not cost-efficient, as a many samples were required to account for the variability in the data. Remote underwater video provided a comprehensive assessment of the reef fish community, however it too was associated with high levels of variability in the data, compared to BRUV, reducing its cost-efficiency. BRUV provided the most comprehensive assessment of the reef fish community and was associated with the highest cost-efficiency to address the community and fisheries species monitoring objectives. During the course of this research stereo-BRUV has gained considerable support as an effective reef fish monitoring method. Although not tested during this research, stereo-BRUV is preferred to BRUV as it provides accurate data on the size of fish. However, the initial investment of stereo-BRUV is over three times that required for the BRUV. Although it is recommended that a baited video technique be used for LTM in the Agulhas Ecoregion, the choice between BRUV and stereo-BRUV will depend on the specific objectives of the programme and the available budget at the implementing agency.
- Full Text:
- Date Issued: 2013
Towards identifying how knowledge management concepts may be applied to enhance the tendering process in South African public sector institutions
- Authors: Kasi, Sizukisa Bridget
- Date: 2013
- Subjects: Letting of contracts -- South Africa , Knowledge management , Public contracts -- South Africa , Transparency in government -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:1150 , http://hdl.handle.net/10962/d1007741 , Letting of contracts -- South Africa , Knowledge management , Public contracts -- South Africa , Transparency in government -- South Africa
- Description: The state of the Tendering Process in South African Government Institutions has become an area of concern in recent years with issues related to transparency, governance and rigid retrospective procedures being cited as impediments to efficiency. In tum, Knowledge Management (KM) and its ability to be applied to all types of organisations to increase efficiency has been popularised extensively. An analysis of KM literature suggested that the principles of KM may be used to increase efficiency and create competitive advantage. This study attempted to identify whether the benefits gained by other organisations through the application of Knowledge Management principles, could be applied to the Tendering Process in South African Government Institutions. The study sought to identify how Knowledge Value Chain by Wang and Ahmed (2005) may be leveraged to create an enhanced Tendering Process. The study then reviewed the Tendering Processes conducted in Australia, United States of America, Malaysia and South Africa and sought to identify the common steps in a tendering process in order to construct a standard tendering process. The Knowledge Value Chain was then applied to this process to create a standard tendering process enhanced by Knowledge Management Principles. The model was compared to the processes currently conducted in two Government institutions and two parastals. The findings indicated that the model is well suited for Government Organisations and would assist in the creation of greater transparency, however the practical implementation of the model is yet unlikely as the model suggest electronic access to information, and the process in South African Government Institutions is predominately paper-based.
- Full Text:
- Date Issued: 2013
- Authors: Kasi, Sizukisa Bridget
- Date: 2013
- Subjects: Letting of contracts -- South Africa , Knowledge management , Public contracts -- South Africa , Transparency in government -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:1150 , http://hdl.handle.net/10962/d1007741 , Letting of contracts -- South Africa , Knowledge management , Public contracts -- South Africa , Transparency in government -- South Africa
- Description: The state of the Tendering Process in South African Government Institutions has become an area of concern in recent years with issues related to transparency, governance and rigid retrospective procedures being cited as impediments to efficiency. In tum, Knowledge Management (KM) and its ability to be applied to all types of organisations to increase efficiency has been popularised extensively. An analysis of KM literature suggested that the principles of KM may be used to increase efficiency and create competitive advantage. This study attempted to identify whether the benefits gained by other organisations through the application of Knowledge Management principles, could be applied to the Tendering Process in South African Government Institutions. The study sought to identify how Knowledge Value Chain by Wang and Ahmed (2005) may be leveraged to create an enhanced Tendering Process. The study then reviewed the Tendering Processes conducted in Australia, United States of America, Malaysia and South Africa and sought to identify the common steps in a tendering process in order to construct a standard tendering process. The Knowledge Value Chain was then applied to this process to create a standard tendering process enhanced by Knowledge Management Principles. The model was compared to the processes currently conducted in two Government institutions and two parastals. The findings indicated that the model is well suited for Government Organisations and would assist in the creation of greater transparency, however the practical implementation of the model is yet unlikely as the model suggest electronic access to information, and the process in South African Government Institutions is predominately paper-based.
- Full Text:
- Date Issued: 2013
Towards the development of a mycoinsecticide to control white grubs (Coleoptera: Scarabaeidae) in South African sugarcane
- Authors: Goble, Tarryn Anne
- Date: 2013
- Subjects: Insecticides -- Environmental aspects Insecticides -- Toxicology Beetles -- South Africa -- KwaZulu-Natal Beetles -- Control -- South Africa -- KwaZulu-Natal Coleophoridae -- South Africa -- KwaZulu-Natal Scarabaeidae -- South Africa -- KwaZulu-Natal Sugarcane -- Diseases and pests -- South Africa -- KwaZulu-Natal Sugarcane -- Diseases and pests -- Control -- South Africa -- KwaZulu-Natal , Insecticides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5586 , http://hdl.handle.net/10962/d1001748
- Description: In the KwaZulu-Natal (KZN) Midlands North region of South Africa, the importance and increased prevalence of endemic scarabaeids, particularly Hypopholis sommeri Burmeister and Schizonycha affinis Boheman (Coleoptera: Melolonthinae), as soil pests of sugarcane, and a need for their control was established. The development of a mycoinsecticide offers an environmentally friendly alternative to chemical insecticides. The identification of a diversity of white grub species, in two Scarabaeidae subfamilies, representing seven genera were collected in sugarcane as a pest complex. Hypopholis sommeri and S. affinis were the most prevalent species. The increased seasonal abundances, diversity and highly aggregated nature of these scarabaeid species in summer months, suggested that targeting and control strategies for these pests should be considered in this season. Increased rainfall, relative humidity and soil temperatures were linked to the increased occurrence of scarab adults and neonate grubs. Beauveria brongniartii (Saccardo) Petch epizootics were recorded at two sites in the KZN Midlands North on H. sommeri. Seventeen different fluorescently-labelled microsatellite PCR primers were used to target 78 isolates of Beauveria sp. DNA. Microsatellite data resolved two distinct clusters of Beauveria isolates which represented the Beauveria bassiana senso stricto (Balsamo) Vuillemin and B. brongniartii species groups. These groupings were supported by two gene regions, the nuclear ribosomal Internal Transcribed Spacer (ITS) and the nuclear B locus (Bloc) gene of which 23 exemplar Beauveria isolates were represented and sequenced. When microsatellite data were analysed, 26 haplotypes among 58 isolates of B. brongniartii were distinguished. Relatively low levels of genetic diversity were detected in B. brongniartii and isolates were shown to be closely related. There was no genetic differentiation between the two sites, Harden Heights and Canema in the KZN Midlands North. High gene flow from swarming H. sommeri beetles is the proposed mechanism for this lack of genetic differentiation between populations. Microsatellite analyses also showed that B. brongniartii conidia were being cycled from arboreal to subterranean habitats in the environment by H. sommeri beetles. This was the first record of this species of fungus causing epizootics on the larvae and adults of H. sommeri in South Africa. The virulence of 21 isolates of Beauveria brongniartii and two isolates of B. bassiana were evaluated against the adults and larvae of S. affinis and the adults of H. sommeri and Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae). Despite being closely-related, B. brongniartii isolates varied significantly in their virulence towards different hosts and highlighted the host specific nature of B. brongniartii towards S. affinis when compared to B. bassiana. Adults of S. affinis were significantly more susceptible to B. brongniartii isolates than the second (L2) or third instar (L3) grubs. The median lethal time (LT₅₀) of the most virulent B. brongniartii isolate (C13) against S. affinis adults was 7.8 days and probit analysis estimated a median lethal concentration (LC₅₀) of 4.4×10⁷ conidia/ml⁻¹. When L2 grubs were treated with a concentration of 1.0×10⁸ conidia/ml⁻¹, B. brongniartii isolates HHWG1, HHB39A and C17 caused mortality in L2 grubs within 18.4-19.8 days (LT₅₀). Beauveria brongniartii isolate HHWG1 was tested against the L3 grubs of S. affinis at four different concentrations. At the lowest concentration (1×10⁶ conidia/ml⁻¹), the LT₅₀ was 25.8 days, and at the highest concentration (1×10⁹ conidia/ml⁻¹) the LT₅₀ dropped to 15.1 days. The persistence of B. bassiana isolate 4222 formulated on rice and wheat bran and buried at eight field sites in the KZN Midlands North was evaluated by plating out a suspension of treated soil onto a selective medium. All eight field sites showed a significant decline in B. bassiana CFUs per gram of soil over time, with few conidia still present in the samples after a year. Greater declines in CFUs were observed at some sites but there were no significant differences observed in the persistence of conidia formulated on rice or wheat bran as carriers. Overall, poor persistence of B. bassiana isolate 4222 was attributed to suboptimum temperatures, rainfall, which rapidly degraded the nutritive carriers, attenuated fungal genotype and the action of antagonistic soil microbes. Growers’ perceptions of white grubs as pests and the feasibility of a mycoinsecticide market were evaluated by means of a semi-structured questionnaire. The study showed that the reduced feasibility of application, general lack of potential demand for a product, high cost factors and most importantly, the lack of pest perception, were factors which would negatively affect the adoption of a granular mycoinsecticide. Growers however exhibited a positive attitude towards mycoinsecticides, and showed all the relevant attributes for successful technology adoption. It is recommended that because B. brongniartii epizootics were recorded on target pests which indicated good host specificity, dispersal ability and persistence of the fungus in the intended environment of application; that a mycoinsecticide based on this fungal species be developed. What will likely increase adoption and success of a mycoinsecticide is collaboration between various industries partners to increases market potential in other crops such as Acacia mearnsii De Wild (Fabales: Fabaceae).
- Full Text:
- Date Issued: 2013
- Authors: Goble, Tarryn Anne
- Date: 2013
- Subjects: Insecticides -- Environmental aspects Insecticides -- Toxicology Beetles -- South Africa -- KwaZulu-Natal Beetles -- Control -- South Africa -- KwaZulu-Natal Coleophoridae -- South Africa -- KwaZulu-Natal Scarabaeidae -- South Africa -- KwaZulu-Natal Sugarcane -- Diseases and pests -- South Africa -- KwaZulu-Natal Sugarcane -- Diseases and pests -- Control -- South Africa -- KwaZulu-Natal , Insecticides
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5586 , http://hdl.handle.net/10962/d1001748
- Description: In the KwaZulu-Natal (KZN) Midlands North region of South Africa, the importance and increased prevalence of endemic scarabaeids, particularly Hypopholis sommeri Burmeister and Schizonycha affinis Boheman (Coleoptera: Melolonthinae), as soil pests of sugarcane, and a need for their control was established. The development of a mycoinsecticide offers an environmentally friendly alternative to chemical insecticides. The identification of a diversity of white grub species, in two Scarabaeidae subfamilies, representing seven genera were collected in sugarcane as a pest complex. Hypopholis sommeri and S. affinis were the most prevalent species. The increased seasonal abundances, diversity and highly aggregated nature of these scarabaeid species in summer months, suggested that targeting and control strategies for these pests should be considered in this season. Increased rainfall, relative humidity and soil temperatures were linked to the increased occurrence of scarab adults and neonate grubs. Beauveria brongniartii (Saccardo) Petch epizootics were recorded at two sites in the KZN Midlands North on H. sommeri. Seventeen different fluorescently-labelled microsatellite PCR primers were used to target 78 isolates of Beauveria sp. DNA. Microsatellite data resolved two distinct clusters of Beauveria isolates which represented the Beauveria bassiana senso stricto (Balsamo) Vuillemin and B. brongniartii species groups. These groupings were supported by two gene regions, the nuclear ribosomal Internal Transcribed Spacer (ITS) and the nuclear B locus (Bloc) gene of which 23 exemplar Beauveria isolates were represented and sequenced. When microsatellite data were analysed, 26 haplotypes among 58 isolates of B. brongniartii were distinguished. Relatively low levels of genetic diversity were detected in B. brongniartii and isolates were shown to be closely related. There was no genetic differentiation between the two sites, Harden Heights and Canema in the KZN Midlands North. High gene flow from swarming H. sommeri beetles is the proposed mechanism for this lack of genetic differentiation between populations. Microsatellite analyses also showed that B. brongniartii conidia were being cycled from arboreal to subterranean habitats in the environment by H. sommeri beetles. This was the first record of this species of fungus causing epizootics on the larvae and adults of H. sommeri in South Africa. The virulence of 21 isolates of Beauveria brongniartii and two isolates of B. bassiana were evaluated against the adults and larvae of S. affinis and the adults of H. sommeri and Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae). Despite being closely-related, B. brongniartii isolates varied significantly in their virulence towards different hosts and highlighted the host specific nature of B. brongniartii towards S. affinis when compared to B. bassiana. Adults of S. affinis were significantly more susceptible to B. brongniartii isolates than the second (L2) or third instar (L3) grubs. The median lethal time (LT₅₀) of the most virulent B. brongniartii isolate (C13) against S. affinis adults was 7.8 days and probit analysis estimated a median lethal concentration (LC₅₀) of 4.4×10⁷ conidia/ml⁻¹. When L2 grubs were treated with a concentration of 1.0×10⁸ conidia/ml⁻¹, B. brongniartii isolates HHWG1, HHB39A and C17 caused mortality in L2 grubs within 18.4-19.8 days (LT₅₀). Beauveria brongniartii isolate HHWG1 was tested against the L3 grubs of S. affinis at four different concentrations. At the lowest concentration (1×10⁶ conidia/ml⁻¹), the LT₅₀ was 25.8 days, and at the highest concentration (1×10⁹ conidia/ml⁻¹) the LT₅₀ dropped to 15.1 days. The persistence of B. bassiana isolate 4222 formulated on rice and wheat bran and buried at eight field sites in the KZN Midlands North was evaluated by plating out a suspension of treated soil onto a selective medium. All eight field sites showed a significant decline in B. bassiana CFUs per gram of soil over time, with few conidia still present in the samples after a year. Greater declines in CFUs were observed at some sites but there were no significant differences observed in the persistence of conidia formulated on rice or wheat bran as carriers. Overall, poor persistence of B. bassiana isolate 4222 was attributed to suboptimum temperatures, rainfall, which rapidly degraded the nutritive carriers, attenuated fungal genotype and the action of antagonistic soil microbes. Growers’ perceptions of white grubs as pests and the feasibility of a mycoinsecticide market were evaluated by means of a semi-structured questionnaire. The study showed that the reduced feasibility of application, general lack of potential demand for a product, high cost factors and most importantly, the lack of pest perception, were factors which would negatively affect the adoption of a granular mycoinsecticide. Growers however exhibited a positive attitude towards mycoinsecticides, and showed all the relevant attributes for successful technology adoption. It is recommended that because B. brongniartii epizootics were recorded on target pests which indicated good host specificity, dispersal ability and persistence of the fungus in the intended environment of application; that a mycoinsecticide based on this fungal species be developed. What will likely increase adoption and success of a mycoinsecticide is collaboration between various industries partners to increases market potential in other crops such as Acacia mearnsii De Wild (Fabales: Fabaceae).
- Full Text:
- Date Issued: 2013
Trade union responses to the casualisation of labour in the Eastern Cape
- Authors: Loni, Kholosa Siphe
- Date: 2013 , 2013-04-23
- Subjects: Labor unions -- Research -- South Africa -- Eastern Cape Casual labor -- Research -- South Africa -- Eastern Cape Precarious employment -- Research -- South Africa -- Eastern Cape Temporary employees -- Legal status, laws, etc. -- Research -- South Africa Industrial relations -- South Africa -- Eastern Cape Labor and globalization
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3286 , http://hdl.handle.net/10962/d1003056
- Description: This thesis focuses on trade union responses to casualisation of labour in the Eastern Cape. In the context of increased globalization, some employers have attempted to achieve high production outputs while saving on operational costs. The ‘flexible firm’ model is used as but one theory to explain increased flexibility in the workplace. In an effort to achieve increasingly flexible firms that may swiftly respond to subsequent challenges such as increased international competition, employers have been seen incorporating more non-standard workers in the form of casual, temporary, part-time, and seasonal workers. This has been a matter of concern for the unions for numerous reasons: some nonstandard workers are subjected to sub-standard working conditions, irregular working hours and little or no benefits; casual work is arranged in such a way that it is virtually impossible for these workers to join a union – a predicament which bears a high possibility of a decline in the typically standard worker–based membership of trade unions; and non-standard workers are often faced with the representation gap predicament which entails that they are not adequately protected by labour legislation. The thesis explores the responses of trade unions to these challenges, and the proposals that they have made in this regard, by focusing on the sectoral dynamics of non-standard labour in the province. It further discusses the regulation of non-standard labour, as poor representation of some non-standard workers bears consequences for the regulation of the practice of non-standard work. The research adopted qualitative research techniques in the form of semi-structured interviews, and used purposive and snowball sampling in accessing relevant data for analysis purposes.
- Full Text:
- Date Issued: 2013
- Authors: Loni, Kholosa Siphe
- Date: 2013 , 2013-04-23
- Subjects: Labor unions -- Research -- South Africa -- Eastern Cape Casual labor -- Research -- South Africa -- Eastern Cape Precarious employment -- Research -- South Africa -- Eastern Cape Temporary employees -- Legal status, laws, etc. -- Research -- South Africa Industrial relations -- South Africa -- Eastern Cape Labor and globalization
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3286 , http://hdl.handle.net/10962/d1003056
- Description: This thesis focuses on trade union responses to casualisation of labour in the Eastern Cape. In the context of increased globalization, some employers have attempted to achieve high production outputs while saving on operational costs. The ‘flexible firm’ model is used as but one theory to explain increased flexibility in the workplace. In an effort to achieve increasingly flexible firms that may swiftly respond to subsequent challenges such as increased international competition, employers have been seen incorporating more non-standard workers in the form of casual, temporary, part-time, and seasonal workers. This has been a matter of concern for the unions for numerous reasons: some nonstandard workers are subjected to sub-standard working conditions, irregular working hours and little or no benefits; casual work is arranged in such a way that it is virtually impossible for these workers to join a union – a predicament which bears a high possibility of a decline in the typically standard worker–based membership of trade unions; and non-standard workers are often faced with the representation gap predicament which entails that they are not adequately protected by labour legislation. The thesis explores the responses of trade unions to these challenges, and the proposals that they have made in this regard, by focusing on the sectoral dynamics of non-standard labour in the province. It further discusses the regulation of non-standard labour, as poor representation of some non-standard workers bears consequences for the regulation of the practice of non-standard work. The research adopted qualitative research techniques in the form of semi-structured interviews, and used purposive and snowball sampling in accessing relevant data for analysis purposes.
- Full Text:
- Date Issued: 2013
Understanding Generation Y : an investigation of how Hilton College can use technology for communication
- Authors: Wyngaard, Richard Clive
- Date: 2013
- Subjects: Generation Y -- South Africa -- KwaZulu-Natal Cell phones -- Social aspects Mobile communication systems -- Social aspects Information technology -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:796 , http://hdl.handle.net/10962/d1004332
- Description: Background to the academic research. Hilton College is an all boys private school in the Kwa-Zulu Natal Midlands. Since the beginning of 2012 boys have been permitted to carry their phones during the school day, (Thomson, 2012). Wireless internet access was also extended across the campus to allow boys and staff to bring their own devices to class and have access to the internet (Machlachlan, 2012). In the past, communication between staff and boys was either verbal or through the use of a daily notice, called the Daily Routine Order (DRO). The DRO is placed at the dining room tables each day and boys are expected to check for any notices that may pertain to them. These notices are emailed to a secretary who prints them out and places them in the dining room each day at lunch. 2. Objectives to the research. This research sought to establish whether current communication methods were effective or whether the prevalence of mobile phones and wireless devices had presented the school with a more effective method. It was important therefore, to investigate what devices were on campus, how those devices were used and when they were used. In addition to this, the research sought to establish communication preference among staff and boys. 3. Research Methodology. The research was conducted through the use of a qualitative survey that was conducted among both staff and boys. Staff and boys were surveyed to establish generation, device prevalence, device usage and device preference. This data was collected using an anonymous qualitative survey that was administered through the use of Google docs in the school labs. 187 Boys in 3 grades 8 and 9 participated in the survey along with 18 staff members. The data was then analysed and compared to data from similar research that had been conducted elsewhere in the world. Because of significant age differences between boys and staff it was critical to establish whether device usage among staff and boys was tied to their generation. Of particular interest were the device behaviours associated with the Millennial generation, who were born between 1982-2002 (Strauss 2005:10). This generational ‘benchmark’ allowed the researcher to compare the Hilton College cohort to those whose device behaviours and usage had occurred and been discussed in generational research elsewhere. It also allowed for certain assumptions to be made about staff and boys based on their generational profile. 4. Findings It was found that staff and boys exhibited communication traits that were consistent with their generation and consistent with other research in this field. It was also found that staff and boys preferred mobile and digital forms of communication over verbal announcements and the DRO system. For this reason, it was recommended that the Hilton College establish a system that took advantage of technology to improve on communication. Various recommendations were given by the researcher that took advantage of current technologies. These included the use of SMS, Instant Messaging, Social Networks and email. It was also recommended that the school consider prescribing devices that allow for communication between staff and boys.
- Full Text:
- Date Issued: 2013
- Authors: Wyngaard, Richard Clive
- Date: 2013
- Subjects: Generation Y -- South Africa -- KwaZulu-Natal Cell phones -- Social aspects Mobile communication systems -- Social aspects Information technology -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:796 , http://hdl.handle.net/10962/d1004332
- Description: Background to the academic research. Hilton College is an all boys private school in the Kwa-Zulu Natal Midlands. Since the beginning of 2012 boys have been permitted to carry their phones during the school day, (Thomson, 2012). Wireless internet access was also extended across the campus to allow boys and staff to bring their own devices to class and have access to the internet (Machlachlan, 2012). In the past, communication between staff and boys was either verbal or through the use of a daily notice, called the Daily Routine Order (DRO). The DRO is placed at the dining room tables each day and boys are expected to check for any notices that may pertain to them. These notices are emailed to a secretary who prints them out and places them in the dining room each day at lunch. 2. Objectives to the research. This research sought to establish whether current communication methods were effective or whether the prevalence of mobile phones and wireless devices had presented the school with a more effective method. It was important therefore, to investigate what devices were on campus, how those devices were used and when they were used. In addition to this, the research sought to establish communication preference among staff and boys. 3. Research Methodology. The research was conducted through the use of a qualitative survey that was conducted among both staff and boys. Staff and boys were surveyed to establish generation, device prevalence, device usage and device preference. This data was collected using an anonymous qualitative survey that was administered through the use of Google docs in the school labs. 187 Boys in 3 grades 8 and 9 participated in the survey along with 18 staff members. The data was then analysed and compared to data from similar research that had been conducted elsewhere in the world. Because of significant age differences between boys and staff it was critical to establish whether device usage among staff and boys was tied to their generation. Of particular interest were the device behaviours associated with the Millennial generation, who were born between 1982-2002 (Strauss 2005:10). This generational ‘benchmark’ allowed the researcher to compare the Hilton College cohort to those whose device behaviours and usage had occurred and been discussed in generational research elsewhere. It also allowed for certain assumptions to be made about staff and boys based on their generational profile. 4. Findings It was found that staff and boys exhibited communication traits that were consistent with their generation and consistent with other research in this field. It was also found that staff and boys preferred mobile and digital forms of communication over verbal announcements and the DRO system. For this reason, it was recommended that the Hilton College establish a system that took advantage of technology to improve on communication. Various recommendations were given by the researcher that took advantage of current technologies. These included the use of SMS, Instant Messaging, Social Networks and email. It was also recommended that the school consider prescribing devices that allow for communication between staff and boys.
- Full Text:
- Date Issued: 2013
Understanding how teachers scaffold learners to make sense of biological language and concepts when using English as a mediational tool: a case study
- Authors: Nakale, Elifas
- Date: 2013
- Subjects: Biology -- Study and teaching (Secondary) -- Namibia Language and education -- Namibia , English as medium of instruction
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1386 , http://hdl.handle.net/10962/d1001517
- Description: For the past few years, Namibian grade 11-12 learners’ achievement level in biology has not been very encouraging. Evidence to this effect is contained in recent examiners’ reports which outline misunderstanding and various misconceptions. The causes of these misunderstandings and misconceptions may be varied, but there is credible evidence that some of it is rooted in the language problem for learners. A classroom is a social unit where many social practices are acquired, including the use of English language. Equally, it is a place where errors in language are learnt and reinforced. Triggered by these challenges facing biology learners, a qualitative case study was conducted at two secondary schools in Ohangwena Region, Namibia. Its purpose was to investigate how biology teachers scaffold learners to make sense of biological language and concepts when English is used as the mediational tool. Underpinned by an interpretivist paradigm, the study made use of document analysis, observation (lessons were also video-taped) and interviews to generate the data. Several data generating techniques were used for triangulation and validation. To further validate the data, transcripts of video-taped lessons and interviews were sent back to the research participants for member checking. The data gathering methods were also used in data presentation, analysis and interpretation to determine the extent of scaffold that teachers provide to their biology learners. The main findings of my study are that, despite efforts by participant teachers to scaffold their learners in making sense of biological language and concepts, success rates in this regard remain disappointingly low due to their (teachers) limited pedagogical content knowledge. Teachers therefore require improved mentorship, monitoring and capacity building.
- Full Text:
- Date Issued: 2013
- Authors: Nakale, Elifas
- Date: 2013
- Subjects: Biology -- Study and teaching (Secondary) -- Namibia Language and education -- Namibia , English as medium of instruction
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1386 , http://hdl.handle.net/10962/d1001517
- Description: For the past few years, Namibian grade 11-12 learners’ achievement level in biology has not been very encouraging. Evidence to this effect is contained in recent examiners’ reports which outline misunderstanding and various misconceptions. The causes of these misunderstandings and misconceptions may be varied, but there is credible evidence that some of it is rooted in the language problem for learners. A classroom is a social unit where many social practices are acquired, including the use of English language. Equally, it is a place where errors in language are learnt and reinforced. Triggered by these challenges facing biology learners, a qualitative case study was conducted at two secondary schools in Ohangwena Region, Namibia. Its purpose was to investigate how biology teachers scaffold learners to make sense of biological language and concepts when English is used as the mediational tool. Underpinned by an interpretivist paradigm, the study made use of document analysis, observation (lessons were also video-taped) and interviews to generate the data. Several data generating techniques were used for triangulation and validation. To further validate the data, transcripts of video-taped lessons and interviews were sent back to the research participants for member checking. The data gathering methods were also used in data presentation, analysis and interpretation to determine the extent of scaffold that teachers provide to their biology learners. The main findings of my study are that, despite efforts by participant teachers to scaffold their learners in making sense of biological language and concepts, success rates in this regard remain disappointingly low due to their (teachers) limited pedagogical content knowledge. Teachers therefore require improved mentorship, monitoring and capacity building.
- Full Text:
- Date Issued: 2013
Understanding livelihood strategies of urban women traders : a case of Magaba, Harare in Zimbabwe
- Authors: Chirau, Takunda John
- Date: 2013
- Subjects: Street vendors -- Zimbabwe -- Harare Women -- Zimbabwe -- Harare -- Social conditions Women -- Zimbabwe -- Harare -- Economic conditions Urban poor -- Zimbabwe -- Harare
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3335 , http://hdl.handle.net/10962/d1003742
- Description: This thesis seeks to understand and analyze the livelihood strategies of urban women traders at Magaba in Harare (Zimbabwe) in the context of the contemporary economic and political crisis. The crisis emerged in the 1990s with the introduction of a structural adjustment programme and deepened further with the fast track land reform programme initiated by the Zimbabwean government in the year 2000. The crisis has involved a down-sizing of the Zimbabwean economy and a massive rise in the rate of unemployment in the formal economy. Consequently urban life became increasingly unbearable for poor blacks and informal economic activities blossomed and started to make a significant contribution to household income and livelihoods. The role of women in the informal economy was particularly pronounced. Theoretically, the thesis is underpinned by the sustainable livelihoods framework. In examining the vulnerability context of the Magaba women traders and the institutional interventions which complicate the lives and livelihoods of these traders, I identify and unpack their diverse livelihood activities and strategies and the resources (or assets) they deploy in constructing urban livelihoods. Though their livelihood portfolios complement any earnings from formal employment by household members and though they contribute to their household’s sustenance, there are a number of daily challenges which they face in their trading activities and which they seek to counteract through a range of often ingenious coping mechanisms. The thesis is important for a number of reasons. It fills an important empirical gap in the study of Magaba market specifically, it brings to the fore the gendered character of the informal trading activities in urban Zimbabwe, and it deploys the livelihoods framework in a manner which is sensitive to both structure and agency.
- Full Text:
- Date Issued: 2013
- Authors: Chirau, Takunda John
- Date: 2013
- Subjects: Street vendors -- Zimbabwe -- Harare Women -- Zimbabwe -- Harare -- Social conditions Women -- Zimbabwe -- Harare -- Economic conditions Urban poor -- Zimbabwe -- Harare
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3335 , http://hdl.handle.net/10962/d1003742
- Description: This thesis seeks to understand and analyze the livelihood strategies of urban women traders at Magaba in Harare (Zimbabwe) in the context of the contemporary economic and political crisis. The crisis emerged in the 1990s with the introduction of a structural adjustment programme and deepened further with the fast track land reform programme initiated by the Zimbabwean government in the year 2000. The crisis has involved a down-sizing of the Zimbabwean economy and a massive rise in the rate of unemployment in the formal economy. Consequently urban life became increasingly unbearable for poor blacks and informal economic activities blossomed and started to make a significant contribution to household income and livelihoods. The role of women in the informal economy was particularly pronounced. Theoretically, the thesis is underpinned by the sustainable livelihoods framework. In examining the vulnerability context of the Magaba women traders and the institutional interventions which complicate the lives and livelihoods of these traders, I identify and unpack their diverse livelihood activities and strategies and the resources (or assets) they deploy in constructing urban livelihoods. Though their livelihood portfolios complement any earnings from formal employment by household members and though they contribute to their household’s sustenance, there are a number of daily challenges which they face in their trading activities and which they seek to counteract through a range of often ingenious coping mechanisms. The thesis is important for a number of reasons. It fills an important empirical gap in the study of Magaba market specifically, it brings to the fore the gendered character of the informal trading activities in urban Zimbabwe, and it deploys the livelihoods framework in a manner which is sensitive to both structure and agency.
- Full Text:
- Date Issued: 2013
Understanding trainee teachers' engagement with prior everyday knowledge and experiences in teaching physical science concepts : a case study
- Authors: Mukwambo, Muzwangowenyu
- Date: 2013
- Subjects: Science -- Study and teaching -- Namibia -- Caprivi -- Case studies Ethnoscience -- Study and teaching -- Namibia -- Caprivi -- Case studies Experiential learning -- Namibia -- Caprivi -- Case studies Experiential learning -- Namibia -- Caprivi -- Case studies Education -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1402 , http://hdl.handle.net/10962/d1001874
- Description: The constructivist world view is advocated in the Namibian National Curriculum for Basic Education (NNCBE, 2010) since it encourages teachers to use different knowledge sources. This perspective embraces a multicultural approach to science teaching and learning. Indigenous knowledge (IK) and western science (WS) are some of the knowledge sources that are advocated. Yet, it has been noted that some science textbooks used in school science curricula do not consider IK. It is often diminished and considered of lesser value. The sole use of WS in teaching and learning is often distant from IK sources which can be used as prior knowledge. In this study, I therefore endeavoured to minimize this gap in the science curriculum. Essentially, the study focused on investigating trainee teachers’ engagement with prior everyday knowledge and experiences of natural phenomena in teaching physical science concepts. The rationale behind the study emerged while I was supervising twelve trainee teachers on school based studies (SBS) in the Caprivi Region. Observations revealed that learners frequently asked trainee teachers to relate their IK to WS to contextualize what they were learning. However, most trainee teachers seemed to experience challenges. This pedagogical gap and challenge was investigated using the instruments below. An analysis was done on the Namibian National Curriculum for Basic Education (NNCBE, 2010), extracts of research papers and a chapters on pressure in physical science textbooks. A worksheet was used to orientate trainee teachers with suggestions on how IK could be fused with WS to contextualize teaching and learning. Thereafter, this was followed by the simultaneous use of brainstorming and audio-visual techniques. Base line instruments paved the way for the main data generating techniques; namely, microteaching, audio-visual techniques, critical partners’ observation and focus group interview. There was triangulation of data collection instruments which enhanced validation followed by tabulation and data collation to develop themes. Analysis entailed checking theme repetition, indigenous categories and key words in context techniques. Themes enabled the construction of analytical statements which were discussed with reference to the relevant literature, theory and subsequently aligned to the research questions. Findings from this study include the suggestions that IK can be incorporated into teaching and learning of science concepts through the use of models or practical activities, science language used in the community and some cultural artifacts. The relevance of incorporating such type of knowledge is to contextualize science teaching and learning. The study therefore concluded that the incorporation of IK into teaching and learning of science concepts; (a) broadens the curriculum as it addresses conceptual progression and cohesion; (b) contextualizes concepts taught; (c) empowers teachers to use a practical curriculum and (d) it also creates space for misconceptions that come with IK to be identified and corrected. The study thus recommends that cultural artifacts and the social science jargon used in the community of the trainee teachers can be used to incorporate IK with WS as these types of knowledge are not mutually exclusive but in fact complement one another.
- Full Text:
- Date Issued: 2013
- Authors: Mukwambo, Muzwangowenyu
- Date: 2013
- Subjects: Science -- Study and teaching -- Namibia -- Caprivi -- Case studies Ethnoscience -- Study and teaching -- Namibia -- Caprivi -- Case studies Experiential learning -- Namibia -- Caprivi -- Case studies Experiential learning -- Namibia -- Caprivi -- Case studies Education -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1402 , http://hdl.handle.net/10962/d1001874
- Description: The constructivist world view is advocated in the Namibian National Curriculum for Basic Education (NNCBE, 2010) since it encourages teachers to use different knowledge sources. This perspective embraces a multicultural approach to science teaching and learning. Indigenous knowledge (IK) and western science (WS) are some of the knowledge sources that are advocated. Yet, it has been noted that some science textbooks used in school science curricula do not consider IK. It is often diminished and considered of lesser value. The sole use of WS in teaching and learning is often distant from IK sources which can be used as prior knowledge. In this study, I therefore endeavoured to minimize this gap in the science curriculum. Essentially, the study focused on investigating trainee teachers’ engagement with prior everyday knowledge and experiences of natural phenomena in teaching physical science concepts. The rationale behind the study emerged while I was supervising twelve trainee teachers on school based studies (SBS) in the Caprivi Region. Observations revealed that learners frequently asked trainee teachers to relate their IK to WS to contextualize what they were learning. However, most trainee teachers seemed to experience challenges. This pedagogical gap and challenge was investigated using the instruments below. An analysis was done on the Namibian National Curriculum for Basic Education (NNCBE, 2010), extracts of research papers and a chapters on pressure in physical science textbooks. A worksheet was used to orientate trainee teachers with suggestions on how IK could be fused with WS to contextualize teaching and learning. Thereafter, this was followed by the simultaneous use of brainstorming and audio-visual techniques. Base line instruments paved the way for the main data generating techniques; namely, microteaching, audio-visual techniques, critical partners’ observation and focus group interview. There was triangulation of data collection instruments which enhanced validation followed by tabulation and data collation to develop themes. Analysis entailed checking theme repetition, indigenous categories and key words in context techniques. Themes enabled the construction of analytical statements which were discussed with reference to the relevant literature, theory and subsequently aligned to the research questions. Findings from this study include the suggestions that IK can be incorporated into teaching and learning of science concepts through the use of models or practical activities, science language used in the community and some cultural artifacts. The relevance of incorporating such type of knowledge is to contextualize science teaching and learning. The study therefore concluded that the incorporation of IK into teaching and learning of science concepts; (a) broadens the curriculum as it addresses conceptual progression and cohesion; (b) contextualizes concepts taught; (c) empowers teachers to use a practical curriculum and (d) it also creates space for misconceptions that come with IK to be identified and corrected. The study thus recommends that cultural artifacts and the social science jargon used in the community of the trainee teachers can be used to incorporate IK with WS as these types of knowledge are not mutually exclusive but in fact complement one another.
- Full Text:
- Date Issued: 2013
Understandings of citizenship in policy and amongst matric learners in three KwaZulu Natal schools
- Authors: Van Lelyveld, Lara Diane
- Date: 2013
- Subjects: Citizenship -- Study and teaching -- Kwazulu-Natal (South Africa) Citizenship -- Social aspects -- Kwazulu-Natal (South Africa)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2847 , http://hdl.handle.net/10962/d1006116
- Description: This thesis explores the difference between the vision of citizenship within education policy and the actual experiences and understandings of citizenship by Matric learners. Citizenship as envisioned in policy is shown to differ significantly to citizenship as understood and experienced by the interview participants. The citizenship envisioned in policy presents the goal of an equal and united citizenry whereas interview participants described citizenship as unequal and hierarchical. In particular, the racial hierarchy enforced under Apartheid was found to dominate the learners’ experiences of citizenship. Despite progressive legislation, distribution of opportunities remains heavily weighted in favour of those in high-income environments. Education policies that determine the overall structure of the South African education system were selected for analysis. These are the Constitution, the South African Schools Act and the National Education Policy Act. These policies are analysed and a vision of South African citizenship is described as possessing the following characteristics. A common, equal citizenship in a united and transformed South Africa. A citizenship encouraging and mandating critical engagement, dialogue, openness and transparency. A citizenship founded on quality of life for all and developing the potential of each individual. A citizenship in which both state and citizen are responsible and accountable and operate within the rule of law. A citizenship underpinned by human dignity and freedom and security of the person. A citizenship in which there is respect for difference and self-determination and in which ‘unity in diversity’ plays a key role. Matric learners were drawn from three different schools in an area of Kwazulu-Natal. Each of these schools represents a ‘type’ of school in South Africa: a former Model C school, an independent school and a school based in a rural or township area. The interviews aimed not only to understand citizenship from the perspective of these learners, but also to understand how experiences of citizenship varied depending on race, gender and class.
- Full Text:
- Date Issued: 2013
- Authors: Van Lelyveld, Lara Diane
- Date: 2013
- Subjects: Citizenship -- Study and teaching -- Kwazulu-Natal (South Africa) Citizenship -- Social aspects -- Kwazulu-Natal (South Africa)
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2847 , http://hdl.handle.net/10962/d1006116
- Description: This thesis explores the difference between the vision of citizenship within education policy and the actual experiences and understandings of citizenship by Matric learners. Citizenship as envisioned in policy is shown to differ significantly to citizenship as understood and experienced by the interview participants. The citizenship envisioned in policy presents the goal of an equal and united citizenry whereas interview participants described citizenship as unequal and hierarchical. In particular, the racial hierarchy enforced under Apartheid was found to dominate the learners’ experiences of citizenship. Despite progressive legislation, distribution of opportunities remains heavily weighted in favour of those in high-income environments. Education policies that determine the overall structure of the South African education system were selected for analysis. These are the Constitution, the South African Schools Act and the National Education Policy Act. These policies are analysed and a vision of South African citizenship is described as possessing the following characteristics. A common, equal citizenship in a united and transformed South Africa. A citizenship encouraging and mandating critical engagement, dialogue, openness and transparency. A citizenship founded on quality of life for all and developing the potential of each individual. A citizenship in which both state and citizen are responsible and accountable and operate within the rule of law. A citizenship underpinned by human dignity and freedom and security of the person. A citizenship in which there is respect for difference and self-determination and in which ‘unity in diversity’ plays a key role. Matric learners were drawn from three different schools in an area of Kwazulu-Natal. Each of these schools represents a ‘type’ of school in South Africa: a former Model C school, an independent school and a school based in a rural or township area. The interviews aimed not only to understand citizenship from the perspective of these learners, but also to understand how experiences of citizenship varied depending on race, gender and class.
- Full Text:
- Date Issued: 2013
Unearthing the essence of nature and the perception of the natural landscape among the amaXhosa in the Eastern Cape : an exploratory study
- Authors: Mogano, Lydia Lehlogonolo
- Date: 2013
- Subjects: Xhosa (African people) -- South Africa -- Eastern Cape Conservation of natural resources -- South Africa -- Eastern Cape Biodiversity conservation -- South Africa -- Eastern Cape Cultural pluralism -- South Africa -- Eastern Cape Human-plant relationships -- South Africa -- Eastern Cape Human ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:1072 , http://hdl.handle.net/10962/d1007742
- Description: The recognition of the close link between the lifestyles of 'indigenous' and 'local' people and biodiversity is widely acknowledged as crucial, not only for the survival of biological diversity but also for the protection of cultural diversity. Most discussions centre on the argument that cultural diversity can, through a wide variety of uses and practices, sustain and conserve biodiversity, particularly in many developing countries. However, local people's relationship with natural landscapes and the extent to which they value biodiversity has not been fully explored and is in most cases misunderstood, which in fact undermines the bio-cultural diversity link. This misunderstanding exists primarily because the majority of environmental or ecological research conducted so far has been oriented towards economic valuation, in quantifying the estimated value of plants and fauna utilised by local people. As a result, biodiversity is primarily treated as a commodity, with wild harvested plant products being classified as either having subsistence, or commercial and medicinal value. This approach is narrow and conceals the critical, profound noneconomic values of biodiversity among local communities in everyday life. Literature indicates that biodiversity and natural landscapes also include less tangible values such as spiritual, cultural, psychological and social values (e.g., sense of place, place attachment, and psychologically restorative effects) which are crucial to human well-being. This suggests that human-nature interaction is complex, and that the meanings and values that people ascribe to natural landscapes cannot be solely reduced to economic values. Nevertheless, to date, studies investigating these less tangible values have received little attention in South Africa. As a result, we have very little understanding of what local and indigenous communities value or appreciate with regard to natural landscapes, beyond their general economic significance. This study seeks to address this particular limitation by exploring non-economic values of natural landscapes and their significances to local people while illuminating the complexities inherent in human-nature interactions. I argue that the purely economic valuation of natural resources is simplistic and biased, and therefore does not represent the complete meaning and significance that natural resources may hold for local communities and households. Therefore, this study takes an innovative psychological approach to explore in detail the everyday lived experiences of the amaXhosa in the Eastern Cape, South Africa. It seeks to investigate the cultural, spiritual, and psychological values that ordinary people attach to natural landscapes in the peri-urban and urban communities of Ndlambe Village l and Grahamstown respectively. This research also aims to study the general perceptions of and meanings ascribed to the natural landscape (referred to by the amaXhosa as ihlathi lesiXhosa). In addition, it carefully integrates the Phenomenological and Transactional approaches to investigate how the amaXhosa engage, interact, and find meaning within the natural landscape. Furthermore, the study explores the impact of such landscape experiences on local people's spiritual and psychological well-being, demonstrating it link to bio-cultural diversity and conservation. The major findings in this study reflect that ihlathi lesiXhosa provides a place for peace and tranquillity to enhance psychological restoration. Moreover, ihlathi contributes towards redefining and strengthening personal and cultural identity; and provides spiritual satisfaction in everyday life. Overall, the findings of this study indicate that i!liathi lesiXhosa plays a profound role in both the personal and social lives of many amaXhosa in the Eastern Cape in that it appears to improve their lives. Therefore, the evidence in this study suggests that, among the amaXhosa, biodiversity and natural landscape management processes should not aim to address and promote ecologicallbiological and economic values in a compartmentalized manner independent of other social, cultural, psychological, and more specifically the spiritual values of these features. An increased understanding of these more intangible values and local people's value system of biodiversity could help towards implementing improved biodiversity conservation and landscape management strategies in South Africa. These insights would not only help us to address the challenges of the previous conservation framework but would also encourage a more inclusive, mutual benefiting process that respects local people's values and needs.
- Full Text:
- Date Issued: 2013
- Authors: Mogano, Lydia Lehlogonolo
- Date: 2013
- Subjects: Xhosa (African people) -- South Africa -- Eastern Cape Conservation of natural resources -- South Africa -- Eastern Cape Biodiversity conservation -- South Africa -- Eastern Cape Cultural pluralism -- South Africa -- Eastern Cape Human-plant relationships -- South Africa -- Eastern Cape Human ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:1072 , http://hdl.handle.net/10962/d1007742
- Description: The recognition of the close link between the lifestyles of 'indigenous' and 'local' people and biodiversity is widely acknowledged as crucial, not only for the survival of biological diversity but also for the protection of cultural diversity. Most discussions centre on the argument that cultural diversity can, through a wide variety of uses and practices, sustain and conserve biodiversity, particularly in many developing countries. However, local people's relationship with natural landscapes and the extent to which they value biodiversity has not been fully explored and is in most cases misunderstood, which in fact undermines the bio-cultural diversity link. This misunderstanding exists primarily because the majority of environmental or ecological research conducted so far has been oriented towards economic valuation, in quantifying the estimated value of plants and fauna utilised by local people. As a result, biodiversity is primarily treated as a commodity, with wild harvested plant products being classified as either having subsistence, or commercial and medicinal value. This approach is narrow and conceals the critical, profound noneconomic values of biodiversity among local communities in everyday life. Literature indicates that biodiversity and natural landscapes also include less tangible values such as spiritual, cultural, psychological and social values (e.g., sense of place, place attachment, and psychologically restorative effects) which are crucial to human well-being. This suggests that human-nature interaction is complex, and that the meanings and values that people ascribe to natural landscapes cannot be solely reduced to economic values. Nevertheless, to date, studies investigating these less tangible values have received little attention in South Africa. As a result, we have very little understanding of what local and indigenous communities value or appreciate with regard to natural landscapes, beyond their general economic significance. This study seeks to address this particular limitation by exploring non-economic values of natural landscapes and their significances to local people while illuminating the complexities inherent in human-nature interactions. I argue that the purely economic valuation of natural resources is simplistic and biased, and therefore does not represent the complete meaning and significance that natural resources may hold for local communities and households. Therefore, this study takes an innovative psychological approach to explore in detail the everyday lived experiences of the amaXhosa in the Eastern Cape, South Africa. It seeks to investigate the cultural, spiritual, and psychological values that ordinary people attach to natural landscapes in the peri-urban and urban communities of Ndlambe Village l and Grahamstown respectively. This research also aims to study the general perceptions of and meanings ascribed to the natural landscape (referred to by the amaXhosa as ihlathi lesiXhosa). In addition, it carefully integrates the Phenomenological and Transactional approaches to investigate how the amaXhosa engage, interact, and find meaning within the natural landscape. Furthermore, the study explores the impact of such landscape experiences on local people's spiritual and psychological well-being, demonstrating it link to bio-cultural diversity and conservation. The major findings in this study reflect that ihlathi lesiXhosa provides a place for peace and tranquillity to enhance psychological restoration. Moreover, ihlathi contributes towards redefining and strengthening personal and cultural identity; and provides spiritual satisfaction in everyday life. Overall, the findings of this study indicate that i!liathi lesiXhosa plays a profound role in both the personal and social lives of many amaXhosa in the Eastern Cape in that it appears to improve their lives. Therefore, the evidence in this study suggests that, among the amaXhosa, biodiversity and natural landscape management processes should not aim to address and promote ecologicallbiological and economic values in a compartmentalized manner independent of other social, cultural, psychological, and more specifically the spiritual values of these features. An increased understanding of these more intangible values and local people's value system of biodiversity could help towards implementing improved biodiversity conservation and landscape management strategies in South Africa. These insights would not only help us to address the challenges of the previous conservation framework but would also encourage a more inclusive, mutual benefiting process that respects local people's values and needs.
- Full Text:
- Date Issued: 2013
Updating the ionospheric propagation factor, M(3000)F2, global model using the neural network technique and relevant geophysical input parameters
- Oronsaye, Samuel Iyen Jeffrey
- Authors: Oronsaye, Samuel Iyen Jeffrey
- Date: 2013
- Subjects: Neural networks (Computer science) , Ionospheric radio wave propagation , Ionosphere , Geophysics , Ionosondes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5434 , http://hdl.handle.net/10962/d1001609 , Neural networks (Computer science) , Ionospheric radio wave propagation , Ionosphere , Geophysics , Ionosondes
- Description: This thesis presents an update to the ionospheric propagation factor, M(3000)F2, global empirical model developed by Oyeyemi et al. (2007) (NNO). An additional aim of this research was to produce the updated model in a form that could be used within the International Reference Ionosphere (IRI) global model without adding to the complexity of the IRI. M(3000)F2 is the highest frequency at which a radio signal can be received over a distance of 3000 km after reflection in the ionosphere. The study employed the artificial neural network (ANN) technique using relevant geophysical input parameters which are known to influence the M(3000)F2 parameter. Ionosonde data from 135 ionospheric stations globally, including a number of equatorial stations, were available for this work. M(3000)F2 hourly values from 1976 to 2008, spanning all periods of low and high solar activity were used for model development and verification. A preliminary investigation was first carried out using a relatively small dataset to determine the appropriate input parameters for global M(3000)F2 parameter modelling. Inputs representing diurnal variation, seasonal variation, solar variation, modified dip latitude, longitude and latitude were found to be the optimum parameters for modelling the diurnal and seasonal variations of the M(3000)F2 parameter both on a temporal and spatial basis. The outcome of the preliminary study was applied to the overall dataset to develop a comprehensive ANN M(3000)F2 model which displays a remarkable improvement over the NNO model as well as the IRI version. The model shows 7.11% and 3.85% improvement over the NNO model as well as 13.04% and 10.05% over the IRI M(3000)F2 model, around high and low solar activity periods respectively. A comparison of the diurnal structure of the ANN and the IRI predicted values reveal that the ANN model is more effective in representing the diurnal structure of the M(3000)F2 values than the IRI M(3000)F2 model. The capability of the ANN model in reproducing the seasonal variation pattern of the M(3000)F2 values at 00h00UT, 06h00UT, 12h00UT, and l8h00UT more appropriately than the IRI version is illustrated in this work. A significant result obtained in this study is the ability of the ANN model in improving the post-sunset predicted values of the M(3000)F2 parameter which is known to be problematic to the IRI M(3000)F2 model in the low-latitude and the equatorial regions. The final M(3000)F2 model provides for an improved equatorial prediction and a simplified input space that allows for easy incorporation into the IRI model.
- Full Text:
- Date Issued: 2013
- Authors: Oronsaye, Samuel Iyen Jeffrey
- Date: 2013
- Subjects: Neural networks (Computer science) , Ionospheric radio wave propagation , Ionosphere , Geophysics , Ionosondes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5434 , http://hdl.handle.net/10962/d1001609 , Neural networks (Computer science) , Ionospheric radio wave propagation , Ionosphere , Geophysics , Ionosondes
- Description: This thesis presents an update to the ionospheric propagation factor, M(3000)F2, global empirical model developed by Oyeyemi et al. (2007) (NNO). An additional aim of this research was to produce the updated model in a form that could be used within the International Reference Ionosphere (IRI) global model without adding to the complexity of the IRI. M(3000)F2 is the highest frequency at which a radio signal can be received over a distance of 3000 km after reflection in the ionosphere. The study employed the artificial neural network (ANN) technique using relevant geophysical input parameters which are known to influence the M(3000)F2 parameter. Ionosonde data from 135 ionospheric stations globally, including a number of equatorial stations, were available for this work. M(3000)F2 hourly values from 1976 to 2008, spanning all periods of low and high solar activity were used for model development and verification. A preliminary investigation was first carried out using a relatively small dataset to determine the appropriate input parameters for global M(3000)F2 parameter modelling. Inputs representing diurnal variation, seasonal variation, solar variation, modified dip latitude, longitude and latitude were found to be the optimum parameters for modelling the diurnal and seasonal variations of the M(3000)F2 parameter both on a temporal and spatial basis. The outcome of the preliminary study was applied to the overall dataset to develop a comprehensive ANN M(3000)F2 model which displays a remarkable improvement over the NNO model as well as the IRI version. The model shows 7.11% and 3.85% improvement over the NNO model as well as 13.04% and 10.05% over the IRI M(3000)F2 model, around high and low solar activity periods respectively. A comparison of the diurnal structure of the ANN and the IRI predicted values reveal that the ANN model is more effective in representing the diurnal structure of the M(3000)F2 values than the IRI M(3000)F2 model. The capability of the ANN model in reproducing the seasonal variation pattern of the M(3000)F2 values at 00h00UT, 06h00UT, 12h00UT, and l8h00UT more appropriately than the IRI version is illustrated in this work. A significant result obtained in this study is the ability of the ANN model in improving the post-sunset predicted values of the M(3000)F2 parameter which is known to be problematic to the IRI M(3000)F2 model in the low-latitude and the equatorial regions. The final M(3000)F2 model provides for an improved equatorial prediction and a simplified input space that allows for easy incorporation into the IRI model.
- Full Text:
- Date Issued: 2013