Phototransformation of pollutants using lutetium and zinc phthalocyanines anchored on electrospun polymer fibers
- Authors: Zugle, Ruphino
- Date: 2013
- Subjects: Electrospinning Phthalocyanines Lutetium Zinc Polymers Dysprosium Pollutants Air Pollution Photochemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4286 , http://hdl.handle.net/10962/d1002962
- Description: Novel lanthanide phthalocyanines containing dysprosium, erbium and lutetium as central metals were synthesized using phthalonitrile:metal salt ratio of 4:1 or lower phthalonitrile content as well as using unmetallated phthalocyanine. They were characterized using various spectroscopic and elemental analyses. Dysprosium bis-phthalocyanine was obtained while monomers were obtained for erbium and lutetium phthalocyanines. Theopen-shelldysprosiumbis-phthalocyanine and the monomeric complex of the open-shell erbium were neither fluorescent nor showed the ability to generate singlet oxygen. The triplet states of all the lutetium phthalocyanines were found to be populated with high triplet quantum yields and corresponding high singlet oxygen quantum yields. The fluorescence quantum yields of the lutetium phthalocyanines were however found to be very low. The lutetium phthalocyanines together with unsubstituted zinc phthalocyanine and its derivatives were successfully incorporated into electrospun polymer fibers either by covalent linkage or sorption forces. Spectral characteristics of the functionalized electrospun polymer fibers indicated that the phthalocyanines were bound and their integrity maintained within the fiber matrices. Most importantly the fluorescence and photoactivity of the phthalocyanines were equally maintained within the electrospun fibers. The functionalized electrospun polymer fibers especially those containing the zinc phthalocyanines could qualitatively detect nitrogen dioxide, a known environmental air pollutant. Also all the functionalized electrospun polystyrene and polysulfone fibers containing lutetium and zinc phthalocyanines could be applied for the photoconversion of 4-chlorophenol, 4-nitrophenol and methyl orange. Those of polystyrene could be re-used. Polyacrylic acid and polyurethane functionalized electrospun fibers were found not to be suitable for photocatalytic applications in aqueous medium. 4-Chlorophenol was found to be more susceptible to photodegradation while methyl orange very difficult to degrade.
- Full Text:
- Date Issued: 2013
- Authors: Zugle, Ruphino
- Date: 2013
- Subjects: Electrospinning Phthalocyanines Lutetium Zinc Polymers Dysprosium Pollutants Air Pollution Photochemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4286 , http://hdl.handle.net/10962/d1002962
- Description: Novel lanthanide phthalocyanines containing dysprosium, erbium and lutetium as central metals were synthesized using phthalonitrile:metal salt ratio of 4:1 or lower phthalonitrile content as well as using unmetallated phthalocyanine. They were characterized using various spectroscopic and elemental analyses. Dysprosium bis-phthalocyanine was obtained while monomers were obtained for erbium and lutetium phthalocyanines. Theopen-shelldysprosiumbis-phthalocyanine and the monomeric complex of the open-shell erbium were neither fluorescent nor showed the ability to generate singlet oxygen. The triplet states of all the lutetium phthalocyanines were found to be populated with high triplet quantum yields and corresponding high singlet oxygen quantum yields. The fluorescence quantum yields of the lutetium phthalocyanines were however found to be very low. The lutetium phthalocyanines together with unsubstituted zinc phthalocyanine and its derivatives were successfully incorporated into electrospun polymer fibers either by covalent linkage or sorption forces. Spectral characteristics of the functionalized electrospun polymer fibers indicated that the phthalocyanines were bound and their integrity maintained within the fiber matrices. Most importantly the fluorescence and photoactivity of the phthalocyanines were equally maintained within the electrospun fibers. The functionalized electrospun polymer fibers especially those containing the zinc phthalocyanines could qualitatively detect nitrogen dioxide, a known environmental air pollutant. Also all the functionalized electrospun polystyrene and polysulfone fibers containing lutetium and zinc phthalocyanines could be applied for the photoconversion of 4-chlorophenol, 4-nitrophenol and methyl orange. Those of polystyrene could be re-used. Polyacrylic acid and polyurethane functionalized electrospun fibers were found not to be suitable for photocatalytic applications in aqueous medium. 4-Chlorophenol was found to be more susceptible to photodegradation while methyl orange very difficult to degrade.
- Full Text:
- Date Issued: 2013
Assessing soil carbon and carbon dioxide effluxes under different vegetation cover conditions in the Eastern Cape Province, South Africa
- Authors: Zengeni, Rebecca
- Date: 2013
- Subjects: Soils -- Carbon content -- Measurement , Carbon dioxide mitigation -- South Africa , Greenhouse gas mitigation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10665 , http://hdl.handle.net/10948/d1018676
- Description: Albany thicket is prevalent in the Eastern Cape Province of South Africa. Its spread has diminished through overgrazing and heavy browsing by animals, land clearance and urban expansion. The result is highly degraded land characterized by invasion of alien species. There is a wealth of documented evidence on the high carbon sequestration ability of thicket biome, but not much has been done to assess its effect on carbon dioxide emissions from the soil. Given that the concentration of atmospheric greenhouse gases has been constantly rising since the industrial era, it is imperative to assess the influence of thicket biome as a source or sink of these gases. There is evidence of shifts in the climate in southern Africa as reflected by changes in rainfall patterns, increased temperatures, recurrent droughts and fires. As such, the historical rainfall variability in an Albany thicket region and its interaction with the temporal land use / cover changes was studied. This served to give some background information about the study area for more detailed study on C and carbon dioxide effluxes in thicket vegetation under different levels of degradation. This study thus aimed to determine the influence of thicket vegetation at various levels of degradation on soil carbon and carbon dioxide fluxes. The impact of plant photosynthetic pathway on soil C residence time and gas effluxes were analysed to elucidate on the land-use and cover patterns occurring in the area. All this was done to shed some light on the role of soil and thicket vegetation on carbon dioxide emissions and C storage in the spectrum of a shifting climate. The main area of research was Amakhala reserve in an Albany thicket in Eastern Cape Province; and it concentrated on three land cover types namely intact thicket, degraded thicket and grassland. The objectives mentioned above were achieved by assessing historical rainfall variability from 1970 to 2010 through trend and time series analysis at nine rainfall stations located at Amakhala reserve, Grahamstown, Bathurst, Port Alfred, Uitenhage and Port Elizabeth. The land use changes that have occurred in the Albany thicket region covering Amakhala reserve, Grahamstown, Bathurst and Port Alfred were also assessed for 1989, 1999 and 2009 through satellite image analysis with Idrisi Andes GIS software; then their interaction with rainfall variability were determined. To elucidate on the vegetation species composition and land use / cover changes that have occurred in the study area, plant biomass as well carbon (C) and nitrogen (N) isotope measurements were done. Plant biomass was assessed for the dominant species through use of pre-existing allometric equations that required data on plant basal diameter, canopy area, stem numbers and height. The plant carbon was then estimated through use of a conversion factor of 0.48 on above-ground biomass, while soil organic C was determined through the modified Walkely - Black method. Carbon and N isotope ratios were determined from the foliar material of three replicate samples of dominant plant species then analyzed through mass spectrometry. Soil carbon dioxide effluxes were then monitored in each of the intact thicket (IT), degraded thicket (DT) and grassland (G) over a 10 month period; by measuring the net carbon dioxide exchange rate (NCER) through the dynamic chamber method. An automated carbon dioxide exchange analyzer, coupled to a soil temperature probe and photosynthetic active radiation (PAR) sensor was used; with NCER measurements taken every 20-30 days. Soil temperature, moisture, penetration resistance and PAR readings were taken during each assay and later used to interpret the NCER. Results showed that long term variability in annual rainfall had a declining trend at Grahamstown (r = -0.59), Uitenhage and Bathurst stations (r = -0.32 at both stations), but was not significant at Amakhala, Port Alfred and Port Elizabeth stations. Most reductions in rainfall occurred in the 1980s and 1990s with the autumn, winter and summer rainfalls, the daily rainfall index and the daily rainfall subclasses of 10 mm and above showing a similar trend. The land use change detection gave a significant increase in proportion of degraded and transformed (moderately degraded) land between 1989 and 2009 with most of the increases occurring from 1989 to 1999, while farmland area decreased by 1.8 percent over the years. Thus the Albany region had over 30 percent of its land occupied by transformed vegetation, with heavy browsing and uncontrolled grazing being attributed to the destruction of pristine vegetation. Land-use change to game ranching and goat pastoralism was attributed to the reduction in farmland. Rainfall variability – land use change linkages were most significant in 1999 that recorded the least rainfall and had the lowest mean, maximum and sum of the NDVI. Grahamstown had the most significant rainfall-NDVI trends as it had the lowest NDVIs in 1999 when rainfall was lowest, the highest NDVI in 1989 when rainfall was highest and moderate NDVIs in 2009 when rainfall was moderate. Vegetation at the IT was characterized by a dense thicket with diverse growth forms of canopy trees, woody shrubs, succulent shrubs and ephemerals which mostly had the C3 type of pathway. This was in contrast with the IT soil isotopy that showed more positive C isotope ratios, indicating a switch between C3 and CAM photosynthesis in original vegetation. Most of the canopy trees had disappeared in the DT to be replaced by herbs, shrubs and grasses. As such, there was a huge difference in isotope ratios between DT plants and soils with the plants having mostly C3 metabolism while the soil showed a predominance of CAM plants in previous vegetation, indicating significant changes in land cover. The G site mostly comprised the grasses Themeda triandra and Panicum maximum and a few herbs. It maintained a dominance of C4 metabolism in both plants and soils showing very little change in species composition over the years. Because of the higher species diversity at IT, its soil organic C was quite high reaching levels of 3.4 percent (i.e. 3.4 t C / ha) in the top 10 cm then decreasing with depth (p < 0.001); but was moderate at DT (1.1-1.3 percent) and very low at G ( 0.5 percent C) (p < 0.001). In the same manner above-ground biomass was highest at IT i.e. 330 000 kg/ha; but was only 22 000 kg/ha in DT and as low as 6 700 kg/ha in G vegetation. High biomass at IT was mostly attributed to the succulent shrub Portulacaria afra and the canopy trees Euclea undulate, Rhus longispina and Schotia afra. This above-ground biomass translated to biomass C amounts of 158 000 kg/ha at IT, 10 600 kg/ha at DT and 3 200 kg/ha at G. Thus the IT had the highest while G the least and DT moderate plant and soil C sequestration ability. In all, the conversion of IT to DT led to a net loss of 147 000 Kg of biomass C / ha and 12 000kg less organic C / ha of land. Soil carbon dioxide effluxes were however variable between seasons as they were affected by differences in soil properties and seasonal weather patterns. High soil moisture levels (up to 16 percent gravimetric moisture) resulted in reduced soil penetration resistance (1 to 4 Kg/cm2) which raised effluxes at G and DT sites (up to 1.2 μmols m-2 sec-1) in winter, while low moisture (2 percent) resulted in hard dry soil (14 Kgm-2 penetration resistance) with suppressed CO2 effluxes in spring (0.2 μmols m-2 sec-1) especially in DT and G soils. Rising temperature generally caused accelerated gas emissions but only when moisture was not limiting (as was the case in IT). Thus the high summer temperatures (up to 40oC) gave lower effluxes especially in DT and G (< 1 μm-2sec-1) due to limited moisture supply (< 10 percent); while the Autumn period that had very high temperature (up to 48 oC) and good moisture (up to 16 percent) saw accelerated soil CO2 emissions (averaging 2 μmols m-2 sec-1) from all cover types. The high biomass and litter fall at IT served as ready substrate for soil respiration as long as moisture was not limiting and temperatures were favourable, while reduced cover at DT resulted in poor moisture conservation and creation of hard dry soils in spring and summer with reduced respiration. It was concluded that the DT had high CO2 effluxes in winter and reduced emissions in summer; while the opposite was true for the IT. All the cover types had minimal CO2 effluxes in spring and accelerated emissions in autumn. The grassland on the other hand was a fairly moderate source or sink of CO2 in most seasons compared with the other two covers. It was observed that an environment of good moisture and low-moderate temperatures (such as that in the winter) minimises effluxes while maintaining good plant productivity. It was concluded that thicket vegetation is a good sink of carbon that should be preserved in its natural condition to optimize its carbon sequestration potential. All three land covers served as sources or sinks of CO2 depending on soil and seasonal conditions. Thus high moisture and low penetration resistance generally increased effluxes of thicket ecosystems. The effect of increasing temperature on effluxes was only significant when moisture was not limiting. Conditions of good moisture and low-moderate temperatures gave reasonable amounts of effluxes while maintaining good plant productivity. Though the dry soil conditions significantly reduced effluxes in all land covers; they were not desirable since they decreased plant productivity and ultimately its C sequestration potential. Moreover, prolonged dry conditions only serve to exacerbate recovery of thicket plants as they increase mortality of canopy species in degraded and transformed areas in comparison with intact thicket.
- Full Text:
- Date Issued: 2013
- Authors: Zengeni, Rebecca
- Date: 2013
- Subjects: Soils -- Carbon content -- Measurement , Carbon dioxide mitigation -- South Africa , Greenhouse gas mitigation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10665 , http://hdl.handle.net/10948/d1018676
- Description: Albany thicket is prevalent in the Eastern Cape Province of South Africa. Its spread has diminished through overgrazing and heavy browsing by animals, land clearance and urban expansion. The result is highly degraded land characterized by invasion of alien species. There is a wealth of documented evidence on the high carbon sequestration ability of thicket biome, but not much has been done to assess its effect on carbon dioxide emissions from the soil. Given that the concentration of atmospheric greenhouse gases has been constantly rising since the industrial era, it is imperative to assess the influence of thicket biome as a source or sink of these gases. There is evidence of shifts in the climate in southern Africa as reflected by changes in rainfall patterns, increased temperatures, recurrent droughts and fires. As such, the historical rainfall variability in an Albany thicket region and its interaction with the temporal land use / cover changes was studied. This served to give some background information about the study area for more detailed study on C and carbon dioxide effluxes in thicket vegetation under different levels of degradation. This study thus aimed to determine the influence of thicket vegetation at various levels of degradation on soil carbon and carbon dioxide fluxes. The impact of plant photosynthetic pathway on soil C residence time and gas effluxes were analysed to elucidate on the land-use and cover patterns occurring in the area. All this was done to shed some light on the role of soil and thicket vegetation on carbon dioxide emissions and C storage in the spectrum of a shifting climate. The main area of research was Amakhala reserve in an Albany thicket in Eastern Cape Province; and it concentrated on three land cover types namely intact thicket, degraded thicket and grassland. The objectives mentioned above were achieved by assessing historical rainfall variability from 1970 to 2010 through trend and time series analysis at nine rainfall stations located at Amakhala reserve, Grahamstown, Bathurst, Port Alfred, Uitenhage and Port Elizabeth. The land use changes that have occurred in the Albany thicket region covering Amakhala reserve, Grahamstown, Bathurst and Port Alfred were also assessed for 1989, 1999 and 2009 through satellite image analysis with Idrisi Andes GIS software; then their interaction with rainfall variability were determined. To elucidate on the vegetation species composition and land use / cover changes that have occurred in the study area, plant biomass as well carbon (C) and nitrogen (N) isotope measurements were done. Plant biomass was assessed for the dominant species through use of pre-existing allometric equations that required data on plant basal diameter, canopy area, stem numbers and height. The plant carbon was then estimated through use of a conversion factor of 0.48 on above-ground biomass, while soil organic C was determined through the modified Walkely - Black method. Carbon and N isotope ratios were determined from the foliar material of three replicate samples of dominant plant species then analyzed through mass spectrometry. Soil carbon dioxide effluxes were then monitored in each of the intact thicket (IT), degraded thicket (DT) and grassland (G) over a 10 month period; by measuring the net carbon dioxide exchange rate (NCER) through the dynamic chamber method. An automated carbon dioxide exchange analyzer, coupled to a soil temperature probe and photosynthetic active radiation (PAR) sensor was used; with NCER measurements taken every 20-30 days. Soil temperature, moisture, penetration resistance and PAR readings were taken during each assay and later used to interpret the NCER. Results showed that long term variability in annual rainfall had a declining trend at Grahamstown (r = -0.59), Uitenhage and Bathurst stations (r = -0.32 at both stations), but was not significant at Amakhala, Port Alfred and Port Elizabeth stations. Most reductions in rainfall occurred in the 1980s and 1990s with the autumn, winter and summer rainfalls, the daily rainfall index and the daily rainfall subclasses of 10 mm and above showing a similar trend. The land use change detection gave a significant increase in proportion of degraded and transformed (moderately degraded) land between 1989 and 2009 with most of the increases occurring from 1989 to 1999, while farmland area decreased by 1.8 percent over the years. Thus the Albany region had over 30 percent of its land occupied by transformed vegetation, with heavy browsing and uncontrolled grazing being attributed to the destruction of pristine vegetation. Land-use change to game ranching and goat pastoralism was attributed to the reduction in farmland. Rainfall variability – land use change linkages were most significant in 1999 that recorded the least rainfall and had the lowest mean, maximum and sum of the NDVI. Grahamstown had the most significant rainfall-NDVI trends as it had the lowest NDVIs in 1999 when rainfall was lowest, the highest NDVI in 1989 when rainfall was highest and moderate NDVIs in 2009 when rainfall was moderate. Vegetation at the IT was characterized by a dense thicket with diverse growth forms of canopy trees, woody shrubs, succulent shrubs and ephemerals which mostly had the C3 type of pathway. This was in contrast with the IT soil isotopy that showed more positive C isotope ratios, indicating a switch between C3 and CAM photosynthesis in original vegetation. Most of the canopy trees had disappeared in the DT to be replaced by herbs, shrubs and grasses. As such, there was a huge difference in isotope ratios between DT plants and soils with the plants having mostly C3 metabolism while the soil showed a predominance of CAM plants in previous vegetation, indicating significant changes in land cover. The G site mostly comprised the grasses Themeda triandra and Panicum maximum and a few herbs. It maintained a dominance of C4 metabolism in both plants and soils showing very little change in species composition over the years. Because of the higher species diversity at IT, its soil organic C was quite high reaching levels of 3.4 percent (i.e. 3.4 t C / ha) in the top 10 cm then decreasing with depth (p < 0.001); but was moderate at DT (1.1-1.3 percent) and very low at G ( 0.5 percent C) (p < 0.001). In the same manner above-ground biomass was highest at IT i.e. 330 000 kg/ha; but was only 22 000 kg/ha in DT and as low as 6 700 kg/ha in G vegetation. High biomass at IT was mostly attributed to the succulent shrub Portulacaria afra and the canopy trees Euclea undulate, Rhus longispina and Schotia afra. This above-ground biomass translated to biomass C amounts of 158 000 kg/ha at IT, 10 600 kg/ha at DT and 3 200 kg/ha at G. Thus the IT had the highest while G the least and DT moderate plant and soil C sequestration ability. In all, the conversion of IT to DT led to a net loss of 147 000 Kg of biomass C / ha and 12 000kg less organic C / ha of land. Soil carbon dioxide effluxes were however variable between seasons as they were affected by differences in soil properties and seasonal weather patterns. High soil moisture levels (up to 16 percent gravimetric moisture) resulted in reduced soil penetration resistance (1 to 4 Kg/cm2) which raised effluxes at G and DT sites (up to 1.2 μmols m-2 sec-1) in winter, while low moisture (2 percent) resulted in hard dry soil (14 Kgm-2 penetration resistance) with suppressed CO2 effluxes in spring (0.2 μmols m-2 sec-1) especially in DT and G soils. Rising temperature generally caused accelerated gas emissions but only when moisture was not limiting (as was the case in IT). Thus the high summer temperatures (up to 40oC) gave lower effluxes especially in DT and G (< 1 μm-2sec-1) due to limited moisture supply (< 10 percent); while the Autumn period that had very high temperature (up to 48 oC) and good moisture (up to 16 percent) saw accelerated soil CO2 emissions (averaging 2 μmols m-2 sec-1) from all cover types. The high biomass and litter fall at IT served as ready substrate for soil respiration as long as moisture was not limiting and temperatures were favourable, while reduced cover at DT resulted in poor moisture conservation and creation of hard dry soils in spring and summer with reduced respiration. It was concluded that the DT had high CO2 effluxes in winter and reduced emissions in summer; while the opposite was true for the IT. All the cover types had minimal CO2 effluxes in spring and accelerated emissions in autumn. The grassland on the other hand was a fairly moderate source or sink of CO2 in most seasons compared with the other two covers. It was observed that an environment of good moisture and low-moderate temperatures (such as that in the winter) minimises effluxes while maintaining good plant productivity. It was concluded that thicket vegetation is a good sink of carbon that should be preserved in its natural condition to optimize its carbon sequestration potential. All three land covers served as sources or sinks of CO2 depending on soil and seasonal conditions. Thus high moisture and low penetration resistance generally increased effluxes of thicket ecosystems. The effect of increasing temperature on effluxes was only significant when moisture was not limiting. Conditions of good moisture and low-moderate temperatures gave reasonable amounts of effluxes while maintaining good plant productivity. Though the dry soil conditions significantly reduced effluxes in all land covers; they were not desirable since they decreased plant productivity and ultimately its C sequestration potential. Moreover, prolonged dry conditions only serve to exacerbate recovery of thicket plants as they increase mortality of canopy species in degraded and transformed areas in comparison with intact thicket.
- Full Text:
- Date Issued: 2013
Representation and use of indigenous heritage constructs : implications for the quality and relevance of heritage education in post colonial southern Africa
- Authors: Zazu, Cryton
- Date: 2013
- Subjects: Albany Museum (Grahamstown, South Africa) Cultural property -- Conservation and restoration -- Research -- Africa, Southern Great Zimbabwe (Extinct city) Indigenous peoples -- Material culture -- Africa, Southern Anthropological museums and collections -- Management -- Research -- Africa, Southern Cultural property -- Management -- Research Ethnoscience -- Study and teaching -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1407 , http://hdl.handle.net/10962/d1002015
- Description: This study explores representation and use of indigenous heritage constructs with a view to identifying implications thereof for the quality and relevance of heritage education practices in post colonial southern Africa. Framed within a critical hermeneutic research paradigm under-laboured by critical realist ontology, the study was conducted using a multiple case study research design. The data collection protocol was three-phased, starting with a process of contextual profiling, within which insights were gained into discourses shaping the constitution and orientation of heritage education practices at the Albany Museum in South Africa, the Great Zimbabwe Monument in Zimbabwe and the Supa Ngwao Museum in Botswana. The second phase of data collection entailed modelling workshops in which educators engaged in discussion around the status of heritage education in post apartheid South Africa. This highlighted, through modelled lessons, some of the tensions, challenges and implications for working with notions of social transformation and inclusivity in heritage education. The third phase of data collection involved in-depth interviews. Twelve purposively selected research participants were interviewed between 2010 and 2011. Data generated across the study was processed and subjected to different levels of critical discourse analysis. Besides noting how heritage education in post colonial southern Africa is poorly framed and under-researched, this study revealed that current forms of representing indigenous heritage constructs are influenced more by socio-political discourses than the need to protect and conserve local heritage resources. The study also noted that the observed heritage education practices are oriented more towards addressing issues related to marginalisation and alienation of indigenous cultures and practices, than enhancing learners’ agency to manage and utilise local heritage resources in a more sustainable ways. Based on these findings the study recommends re-positioning heritage education within the framework of Education for Sustainable Development (ESD). ESD acknowledges both issues of social justice and the dialectical interplay between nature and culture; as such, it may allow for representation and use of indigenous heritage constructs in ways that expand current political orientations to include sustainability as an additional objective of heritage education. Given that little research focusing on heritage education has been undertaken within southern Africa, the findings of this study provide a basis upon which future research may emerge.
- Full Text:
- Date Issued: 2013
- Authors: Zazu, Cryton
- Date: 2013
- Subjects: Albany Museum (Grahamstown, South Africa) Cultural property -- Conservation and restoration -- Research -- Africa, Southern Great Zimbabwe (Extinct city) Indigenous peoples -- Material culture -- Africa, Southern Anthropological museums and collections -- Management -- Research -- Africa, Southern Cultural property -- Management -- Research Ethnoscience -- Study and teaching -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1407 , http://hdl.handle.net/10962/d1002015
- Description: This study explores representation and use of indigenous heritage constructs with a view to identifying implications thereof for the quality and relevance of heritage education practices in post colonial southern Africa. Framed within a critical hermeneutic research paradigm under-laboured by critical realist ontology, the study was conducted using a multiple case study research design. The data collection protocol was three-phased, starting with a process of contextual profiling, within which insights were gained into discourses shaping the constitution and orientation of heritage education practices at the Albany Museum in South Africa, the Great Zimbabwe Monument in Zimbabwe and the Supa Ngwao Museum in Botswana. The second phase of data collection entailed modelling workshops in which educators engaged in discussion around the status of heritage education in post apartheid South Africa. This highlighted, through modelled lessons, some of the tensions, challenges and implications for working with notions of social transformation and inclusivity in heritage education. The third phase of data collection involved in-depth interviews. Twelve purposively selected research participants were interviewed between 2010 and 2011. Data generated across the study was processed and subjected to different levels of critical discourse analysis. Besides noting how heritage education in post colonial southern Africa is poorly framed and under-researched, this study revealed that current forms of representing indigenous heritage constructs are influenced more by socio-political discourses than the need to protect and conserve local heritage resources. The study also noted that the observed heritage education practices are oriented more towards addressing issues related to marginalisation and alienation of indigenous cultures and practices, than enhancing learners’ agency to manage and utilise local heritage resources in a more sustainable ways. Based on these findings the study recommends re-positioning heritage education within the framework of Education for Sustainable Development (ESD). ESD acknowledges both issues of social justice and the dialectical interplay between nature and culture; as such, it may allow for representation and use of indigenous heritage constructs in ways that expand current political orientations to include sustainability as an additional objective of heritage education. Given that little research focusing on heritage education has been undertaken within southern Africa, the findings of this study provide a basis upon which future research may emerge.
- Full Text:
- Date Issued: 2013
A chronic care coordination model for HIV-positive children requiring antiretroviral therapy
- Authors: Williams, Margaret
- Date: 2013
- Subjects: HIV-positive children -- Care -- South Africa , HIV-positive persons -- Care -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10062 , http://hdl.handle.net/10948/d1020346
- Description: The human immunodeficiency virus / acquired immune deficiency syndrome pandemic (HIV/AIDS) continues to increase in prevalence worldwide, particularly in South Africa. There is a concurrent and distinct increase in the prevalence of HIV/AIDS and HIV-related diseases in the paediatric population in South Africa, particularly those using public sector health services, with a corresponding increase in morbidity and mortality rates (Abdool Karim & Abdool Karim, 2010:363), which impacts greatly on paediatric healthcare services. Adding to this, the provision of paediatric antiretroviral care has numerous stumbling blocks, not least of which is lack of decentralisation of facilities to provide treatment. There is the additional shortage of staff, which includes staff that are comfortable dealing with children, lack of training programmes on the provision of antiretroviral therapy to children, and minimal on-site mentorship of staff regarding HIV/AIDS disease in children. This lack of capacity in the healthcare system means that not all of those who require treatment will be able to access it, and this is particularly pertinent to paediatric patients (Meyers et al., 2007:198). Therefore the purpose of this research was to develop a nursing model that would assist healthcare professionals, in particular professional nurses, to optimise the comprehensive treatment, care and support for HIV-positive children who require antiretroviral therapy at PHC clinics. To achieve the purpose of this study, a theory-generating design based on a qualitative, explorative, descriptive and contextual approach was implemented by the researcher to gain an understanding of how the healthcare professionals and parents/caregivers of HIV-positive children experienced the comprehensive treatment, care and support provided at primary healthcare clinics. The information obtained was used to develop a chronic care coordination model for the optimisation of comprehensive treatment, care and support for HIV-positive children requiring antiretroviral therapy. The study design comprised the following four steps: Step One of the research design focused on the identification, classification and definition of the major concepts of the study. This involved describing and selecting the research population and the sampling process prior to conducting the field work which comprised in-depth interviews with two groups of participants, namely healthcare professionals and parents/caregivers who accompany their HIV-positive children to PHC clinics in order to receive antiretroviral therapy. Step Two of the research design focused on the development of relationship statements in order to bring clarity and direction to the understanding of the phenomenon of interest. Step Three of the design concentrated on the development and description of the chronic care coordination model for optimising comprehensive treatment, care and support for HIV-positive children who require antiretroviral therapy in order to ensure a well-managed child on ART. A visual representation of the structure of the model for chronic care coordination was given and described as well as a detailed description of the process of the model. Step Four was the last step of the research design and its focus was the development of guidelines for the operationalisation of the model for chronic care coordination for the optimisation of comprehensive treatment, care and support for HIV-positive children requiring antiretroviral therapy at PHC clinics. Guidelines and operational implications for each of the five sequential steps of the model were developed. The evaluation criteria of Chinn & Kramer (2008:237‒248) were used to evaluate the model. It is therefore concluded that the researcher succeeded in achieving the purpose for this study because a chronic care coordination model that is understandable, clear, simple, applicable and significant to nursing practice has been developed for use by healthcare professionals, particularly professional nurses, in order to optimise the comprehensive treatment, care and support for HIV-positive children requiring antiretroviral therapy at primary healthcare clinics.
- Full Text:
- Date Issued: 2013
- Authors: Williams, Margaret
- Date: 2013
- Subjects: HIV-positive children -- Care -- South Africa , HIV-positive persons -- Care -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10062 , http://hdl.handle.net/10948/d1020346
- Description: The human immunodeficiency virus / acquired immune deficiency syndrome pandemic (HIV/AIDS) continues to increase in prevalence worldwide, particularly in South Africa. There is a concurrent and distinct increase in the prevalence of HIV/AIDS and HIV-related diseases in the paediatric population in South Africa, particularly those using public sector health services, with a corresponding increase in morbidity and mortality rates (Abdool Karim & Abdool Karim, 2010:363), which impacts greatly on paediatric healthcare services. Adding to this, the provision of paediatric antiretroviral care has numerous stumbling blocks, not least of which is lack of decentralisation of facilities to provide treatment. There is the additional shortage of staff, which includes staff that are comfortable dealing with children, lack of training programmes on the provision of antiretroviral therapy to children, and minimal on-site mentorship of staff regarding HIV/AIDS disease in children. This lack of capacity in the healthcare system means that not all of those who require treatment will be able to access it, and this is particularly pertinent to paediatric patients (Meyers et al., 2007:198). Therefore the purpose of this research was to develop a nursing model that would assist healthcare professionals, in particular professional nurses, to optimise the comprehensive treatment, care and support for HIV-positive children who require antiretroviral therapy at PHC clinics. To achieve the purpose of this study, a theory-generating design based on a qualitative, explorative, descriptive and contextual approach was implemented by the researcher to gain an understanding of how the healthcare professionals and parents/caregivers of HIV-positive children experienced the comprehensive treatment, care and support provided at primary healthcare clinics. The information obtained was used to develop a chronic care coordination model for the optimisation of comprehensive treatment, care and support for HIV-positive children requiring antiretroviral therapy. The study design comprised the following four steps: Step One of the research design focused on the identification, classification and definition of the major concepts of the study. This involved describing and selecting the research population and the sampling process prior to conducting the field work which comprised in-depth interviews with two groups of participants, namely healthcare professionals and parents/caregivers who accompany their HIV-positive children to PHC clinics in order to receive antiretroviral therapy. Step Two of the research design focused on the development of relationship statements in order to bring clarity and direction to the understanding of the phenomenon of interest. Step Three of the design concentrated on the development and description of the chronic care coordination model for optimising comprehensive treatment, care and support for HIV-positive children who require antiretroviral therapy in order to ensure a well-managed child on ART. A visual representation of the structure of the model for chronic care coordination was given and described as well as a detailed description of the process of the model. Step Four was the last step of the research design and its focus was the development of guidelines for the operationalisation of the model for chronic care coordination for the optimisation of comprehensive treatment, care and support for HIV-positive children requiring antiretroviral therapy at PHC clinics. Guidelines and operational implications for each of the five sequential steps of the model were developed. The evaluation criteria of Chinn & Kramer (2008:237‒248) were used to evaluate the model. It is therefore concluded that the researcher succeeded in achieving the purpose for this study because a chronic care coordination model that is understandable, clear, simple, applicable and significant to nursing practice has been developed for use by healthcare professionals, particularly professional nurses, in order to optimise the comprehensive treatment, care and support for HIV-positive children requiring antiretroviral therapy at primary healthcare clinics.
- Full Text:
- Date Issued: 2013
A framework for assuring conformance of cloud-based email at higher education institutions
- Authors: Willett, Melanie
- Date: 2013
- Subjects: Cloud computing -- Security measures , Computer networks -- Security measures , Web services , Education, Higher -- Technological innovations
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9815 , http://hdl.handle.net/10948/d1018664
- Description: Cloud computing is a relatively immature computing paradigm that could significantly benefit users. Cloud computing solutions are often associated with potential benefits such as cost reduction, less administrative hassle, flexibility and scalability. For organisations to realize such potential benefits, cloud computing solutions need to be chosen, implemented, managed and governed in a way that is secure, compliant with internal and external requirements and indicative of due diligence. This can be a challenge, given the many concerns and risks commonly associated with cloud computing solutions. One cloud computing solution that is being widely adopted around the world is cloud-based email. One of the foremost adopters of this cloud computing solution is higher education institutions. These higher education institutions stand to benefit greatly from using such services. Cloud-based email can be provisioned to staff and students at these institutions for free. Additionally, cloud service providers (CSPs) are able to provide a better email service than some higher education institutions would be able to provide if they were required to do so in-house. CSPs often provide larger inboxes and many extra services with cloud-based email. Cloud-based email is, therefore, clearly an example of a cloud computing solution that has the potential to benefit organisations. There are however, risks and challenges associated with the use of this cloud computing solution. Two of these challenges relate to ensuring conformance to internal and external (legal, regulatory and contractual obligations) requirements and to providing a mechanism of assuring that cloud-based email related activities are sound. The lack of structured guidelines for assuring the conformance of cloud-based email is putting this service at risk at higher education institutions in South Africa. This work addresses this problem by promoting a best practice based approach to assuring the conformance of cloud-based email at higher education institutions. To accomplish this, components of applicable standards and best practice guidelines for IT governance, IT assurance and IT conformance are used to construct a framework for assuring the conformance of cloud-based email. The framework is designed and verified using sound design science principles. The utility and value of the framework has been demonstrated at a higher education institution in South Africa. This framework can be used to assist higher education institutions to demonstrate due diligence in assuring that they conform to legal and best practice requirements for the management and governance of cloud-based email. This is a significant contribution in the relatively new field of cloud computing governance.
- Full Text:
- Date Issued: 2013
- Authors: Willett, Melanie
- Date: 2013
- Subjects: Cloud computing -- Security measures , Computer networks -- Security measures , Web services , Education, Higher -- Technological innovations
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9815 , http://hdl.handle.net/10948/d1018664
- Description: Cloud computing is a relatively immature computing paradigm that could significantly benefit users. Cloud computing solutions are often associated with potential benefits such as cost reduction, less administrative hassle, flexibility and scalability. For organisations to realize such potential benefits, cloud computing solutions need to be chosen, implemented, managed and governed in a way that is secure, compliant with internal and external requirements and indicative of due diligence. This can be a challenge, given the many concerns and risks commonly associated with cloud computing solutions. One cloud computing solution that is being widely adopted around the world is cloud-based email. One of the foremost adopters of this cloud computing solution is higher education institutions. These higher education institutions stand to benefit greatly from using such services. Cloud-based email can be provisioned to staff and students at these institutions for free. Additionally, cloud service providers (CSPs) are able to provide a better email service than some higher education institutions would be able to provide if they were required to do so in-house. CSPs often provide larger inboxes and many extra services with cloud-based email. Cloud-based email is, therefore, clearly an example of a cloud computing solution that has the potential to benefit organisations. There are however, risks and challenges associated with the use of this cloud computing solution. Two of these challenges relate to ensuring conformance to internal and external (legal, regulatory and contractual obligations) requirements and to providing a mechanism of assuring that cloud-based email related activities are sound. The lack of structured guidelines for assuring the conformance of cloud-based email is putting this service at risk at higher education institutions in South Africa. This work addresses this problem by promoting a best practice based approach to assuring the conformance of cloud-based email at higher education institutions. To accomplish this, components of applicable standards and best practice guidelines for IT governance, IT assurance and IT conformance are used to construct a framework for assuring the conformance of cloud-based email. The framework is designed and verified using sound design science principles. The utility and value of the framework has been demonstrated at a higher education institution in South Africa. This framework can be used to assist higher education institutions to demonstrate due diligence in assuring that they conform to legal and best practice requirements for the management and governance of cloud-based email. This is a significant contribution in the relatively new field of cloud computing governance.
- Full Text:
- Date Issued: 2013
A strategy to facilitate renewed resilience to re-establish meaning for persons with spinal cord injuries
- Authors: Willemse, Hermanus Barend
- Date: 2013
- Subjects: Spinal cord -- Wounds and injuries , Spinal cord -- Wounds and injuries -- Rehabilitation
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10021 , http://hdl.handle.net/10948/d1008119 , Spinal cord -- Wounds and injuries , Spinal cord -- Wounds and injuries -- Rehabilitation
- Description: Census estimates in 2010 indicated that 6,3 percent South Africans aged 5 years and older are currently classified as disabled in five of the nine provinces in the country. The national figure for 2005 was 5 percent, with the figure for females (6,5 percent) slightly higher than that for males (6,1percent). Spinal cord injured persons and their significant others experience a range of emotions which affect their relationships with themselves, others and their environment. To deal with the life-changing consequences of the injury and regain control, these persons not only require a variety of coping strategies but rediscovery of resilience is inevitable if the experience of personal purpose and meaningful existence is ever to be regained. In the Nelson Mandela Bay Municipal area, Port Elizabeth, South Africa – the geographical area in which this research study was undertaken - persons with spinal cord injuries have many challenges to face due to the shortcomings the existing resource for health care delivery in the post-discharge phase. The research objectives identified for the study were, firstly, to explore and describe the lived experiences of persons with spinal cord injuries; secondly, to explore and describe the lived experiences of the significant others of persons with spinal cord injuries; and thirdly, to develop a strategy to guide the professional nurse and the health care team in facilitating the health care of persons with spinal cord injuries. The study was a qualitative, exploratory, descriptive, and contextual method of inquiry. The data obtained was used to formulate the strategy with its three sub-strategies to guide professional nurses and the health care team to facilitate renewed resilience and the re-establishment of meaning for persons with spinal cord injuries. Although the experiences of the significant others were explored in order to thicken the description of the experiences of persons with spinal cord injuries, the strategy developed was limited to the persons with spinal cord injuries. Although it is well documented that there are significant physical needs, the themes that emerged from the current research mostly related to psychological and social aspects. In acknowledging the human being as unitary multi-dimensional being, the researcher in his discussions and quest to address the issue of renewed resilience in spinal cord injured persons towards finding purpose and re-establishing meaning in their lives, focused on their psychological, spiritual and social health. The outcome of the study is a strategy constructed to facilitate renewed resilience, and three sub-strategies ‘addressing experienced emotions’, ‘facilitating meaningful relationships’ and ‘facilitating effective coping’. The strategy has as purpose the empowering of spinal injured persons in their efforts to re-establish meaning by serving as a tool to guide professional nurses and members of the health care team in their facilitating of renewed resilience in persons with spinal cord injury. It is envisaged that the co-ordination of the strategy will take place from the health care delivery facility nearest to the spinal cord injured individual concerned. In order for persons with spinal cord injuries to become accountable members of society, all levels and aspects of care aimed at physical, psychological, spiritual and social well-being need to be holistically addressed. The front-line role of the professional nurse is vital as the professional nurse acts as the co-ordinator for the health care team in ensuring that persons with spinal cord injuries receive quality and holistic care in order to deal meaningfully with the life-altering consequences of a spinal cord injury. Through this study, valuable insight was gained with regard to experiences of both persons with spinal cord injuries and that of their significant others. Recommendations were made for nursing practice, nursing education and nursing research.
- Full Text:
- Date Issued: 2013
- Authors: Willemse, Hermanus Barend
- Date: 2013
- Subjects: Spinal cord -- Wounds and injuries , Spinal cord -- Wounds and injuries -- Rehabilitation
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10021 , http://hdl.handle.net/10948/d1008119 , Spinal cord -- Wounds and injuries , Spinal cord -- Wounds and injuries -- Rehabilitation
- Description: Census estimates in 2010 indicated that 6,3 percent South Africans aged 5 years and older are currently classified as disabled in five of the nine provinces in the country. The national figure for 2005 was 5 percent, with the figure for females (6,5 percent) slightly higher than that for males (6,1percent). Spinal cord injured persons and their significant others experience a range of emotions which affect their relationships with themselves, others and their environment. To deal with the life-changing consequences of the injury and regain control, these persons not only require a variety of coping strategies but rediscovery of resilience is inevitable if the experience of personal purpose and meaningful existence is ever to be regained. In the Nelson Mandela Bay Municipal area, Port Elizabeth, South Africa – the geographical area in which this research study was undertaken - persons with spinal cord injuries have many challenges to face due to the shortcomings the existing resource for health care delivery in the post-discharge phase. The research objectives identified for the study were, firstly, to explore and describe the lived experiences of persons with spinal cord injuries; secondly, to explore and describe the lived experiences of the significant others of persons with spinal cord injuries; and thirdly, to develop a strategy to guide the professional nurse and the health care team in facilitating the health care of persons with spinal cord injuries. The study was a qualitative, exploratory, descriptive, and contextual method of inquiry. The data obtained was used to formulate the strategy with its three sub-strategies to guide professional nurses and the health care team to facilitate renewed resilience and the re-establishment of meaning for persons with spinal cord injuries. Although the experiences of the significant others were explored in order to thicken the description of the experiences of persons with spinal cord injuries, the strategy developed was limited to the persons with spinal cord injuries. Although it is well documented that there are significant physical needs, the themes that emerged from the current research mostly related to psychological and social aspects. In acknowledging the human being as unitary multi-dimensional being, the researcher in his discussions and quest to address the issue of renewed resilience in spinal cord injured persons towards finding purpose and re-establishing meaning in their lives, focused on their psychological, spiritual and social health. The outcome of the study is a strategy constructed to facilitate renewed resilience, and three sub-strategies ‘addressing experienced emotions’, ‘facilitating meaningful relationships’ and ‘facilitating effective coping’. The strategy has as purpose the empowering of spinal injured persons in their efforts to re-establish meaning by serving as a tool to guide professional nurses and members of the health care team in their facilitating of renewed resilience in persons with spinal cord injury. It is envisaged that the co-ordination of the strategy will take place from the health care delivery facility nearest to the spinal cord injured individual concerned. In order for persons with spinal cord injuries to become accountable members of society, all levels and aspects of care aimed at physical, psychological, spiritual and social well-being need to be holistically addressed. The front-line role of the professional nurse is vital as the professional nurse acts as the co-ordinator for the health care team in ensuring that persons with spinal cord injuries receive quality and holistic care in order to deal meaningfully with the life-altering consequences of a spinal cord injury. Through this study, valuable insight was gained with regard to experiences of both persons with spinal cord injuries and that of their significant others. Recommendations were made for nursing practice, nursing education and nursing research.
- Full Text:
- Date Issued: 2013
The development of an integrated value chain cost reduction methodology
- Welman, Abraham Jacobus Frederik
- Authors: Welman, Abraham Jacobus Frederik
- Date: 2013
- Subjects: Corporations -- Finance -- Management , Manufacturing industries -- Cost control , Industrial procurement
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:8775 , http://hdl.handle.net/10948/d1012954
- Description: The reason for the existence of any company is to make a profit, which means increasing turnover and keeping costs as low as possible. Optimisation of the Value Chain and Procurement were identified as the two largest contributors when one needs to improve the bottom line of any company. The purpose of this research was to develop an integrated Value Chain and Procurement cost reduction methodology and system specifications for a software solution which captures, tracks and accurately reports the impact of the improvement initiatives. The main research question was structured as follows: What should the specifications of a software solution be that will integrate the cost reduction processes of the Value Chain and of Procurement, in a manner that will ensure maximum sustainable bottom-line savings for companies in the manufacturing or service industries? The objective was to define the key phases in the Value Chain and Procurement cost reduction process and to determine how and where they integrate. It is important to note that according the literature review and the survey, both the Value Chain and Procurement cost reduction processes consist of seven phases. The phases of the Value Chain cost reduction process were: Phase 1: Budget/ABC costing and data analysis; Phase 2: Generate ideas; Phase 3: Evaluate and approve ideas; Phase 4: Implementation planning and approval; Phase 5: Development of project (idea) specific KPI's; Phase 6: Implementation of ideas; Phase 7: Track and report savings. The phases of the Procurement (Strategic Sourcing) cost reduction process were: Phase 1: Team selection/data collection/spend analysis/work plan development Phase 2: Access requirements/internal and external analysis; Phase 3: Develop strategy/shape value proposition; Phase 4: Screen suppliers, issue RFI/P/Q, implementation planning; Phase 5: Conduct commercial event/negotiate/finalise contract; Phase 6: Implement contract; Phase 7: Contract management/track and reporting. The above two cost reduction processes integrate at each phase of the respective processes and should thus be implemented at the same time due to their interdependencies. Based on the findings of the research it was clear that an integrated Value Chain and Procurement cost reduction process alone is not going to solve the cost reduction problems of companies. It is essential for the successful implementation of the integrated cost reduction process to develop skills and knowledgeable resources to implement the integrated cost reduction process, improve collaboration between the Value Chain and Procurement, and to implement a system to track and report performance during implementation. Further research should include how to adapt the current company processes, structures, procedures and systems in order to gain maximum benefit from the implementation of an integrated cost reduction process. The integrated Value Chain and Procurement cost reduction process, supported by a software system, should improve the success of cost reduction projects in companies. It is, however, important to note that the application of the methodology will vary between industries and that service-related industries might put more emphasis on Procurement cost reduction, while the manufacturing industries might place a bigger emphasis on cost reduction in operations. In conclusion, irrespective of the industries, it is evident that this methodology will enhance the cost reduction results previously obtained from similar efforts.
- Full Text:
- Date Issued: 2013
- Authors: Welman, Abraham Jacobus Frederik
- Date: 2013
- Subjects: Corporations -- Finance -- Management , Manufacturing industries -- Cost control , Industrial procurement
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:8775 , http://hdl.handle.net/10948/d1012954
- Description: The reason for the existence of any company is to make a profit, which means increasing turnover and keeping costs as low as possible. Optimisation of the Value Chain and Procurement were identified as the two largest contributors when one needs to improve the bottom line of any company. The purpose of this research was to develop an integrated Value Chain and Procurement cost reduction methodology and system specifications for a software solution which captures, tracks and accurately reports the impact of the improvement initiatives. The main research question was structured as follows: What should the specifications of a software solution be that will integrate the cost reduction processes of the Value Chain and of Procurement, in a manner that will ensure maximum sustainable bottom-line savings for companies in the manufacturing or service industries? The objective was to define the key phases in the Value Chain and Procurement cost reduction process and to determine how and where they integrate. It is important to note that according the literature review and the survey, both the Value Chain and Procurement cost reduction processes consist of seven phases. The phases of the Value Chain cost reduction process were: Phase 1: Budget/ABC costing and data analysis; Phase 2: Generate ideas; Phase 3: Evaluate and approve ideas; Phase 4: Implementation planning and approval; Phase 5: Development of project (idea) specific KPI's; Phase 6: Implementation of ideas; Phase 7: Track and report savings. The phases of the Procurement (Strategic Sourcing) cost reduction process were: Phase 1: Team selection/data collection/spend analysis/work plan development Phase 2: Access requirements/internal and external analysis; Phase 3: Develop strategy/shape value proposition; Phase 4: Screen suppliers, issue RFI/P/Q, implementation planning; Phase 5: Conduct commercial event/negotiate/finalise contract; Phase 6: Implement contract; Phase 7: Contract management/track and reporting. The above two cost reduction processes integrate at each phase of the respective processes and should thus be implemented at the same time due to their interdependencies. Based on the findings of the research it was clear that an integrated Value Chain and Procurement cost reduction process alone is not going to solve the cost reduction problems of companies. It is essential for the successful implementation of the integrated cost reduction process to develop skills and knowledgeable resources to implement the integrated cost reduction process, improve collaboration between the Value Chain and Procurement, and to implement a system to track and report performance during implementation. Further research should include how to adapt the current company processes, structures, procedures and systems in order to gain maximum benefit from the implementation of an integrated cost reduction process. The integrated Value Chain and Procurement cost reduction process, supported by a software system, should improve the success of cost reduction projects in companies. It is, however, important to note that the application of the methodology will vary between industries and that service-related industries might put more emphasis on Procurement cost reduction, while the manufacturing industries might place a bigger emphasis on cost reduction in operations. In conclusion, irrespective of the industries, it is evident that this methodology will enhance the cost reduction results previously obtained from similar efforts.
- Full Text:
- Date Issued: 2013
Development of a creep sample retrieval technique and friction weld site repair procedure
- Authors: Wedderburn, Ian Norman
- Date: 2013
- Subjects: Friction welding
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9635 , http://hdl.handle.net/10948/d1020116
- Description: The remnant life monitoring of creep loaded high temperature and pressure components in power stations is critical to ensuring their safe and cost effective operation as failures can have severe consequences. Effective creep life condition monitoring allows for optimising component life predictions and subsequent plant maintenance decisions. In South Africa many power generation stations have been in operation well beyond their 30 year design service life, as such knowledge of the remnant creep life of high temperature and pressure components, such as steam pipelines, becomes of utmost importance. Techniques for the remnant creep life assessments of critical high temperature and pressure components must therefore be as effective as possible. The common and well accepted in-situ inspection technique for assessing creep damage in steam pipes is by the metallographic replication technique. The technique is however limited to the outer surface of the pipe, without information on damage within the wall. This research will illustrate a means of obtaining a sample for creep life analysis with depth through the wall of a pipe, as wells as an alternative technique for the repair of the sample retrieval site. A sample retrieval technique was developed that would retrieve a small diameter cylindrical sample from a cored blind hole for creep analysis by visual creep void assessment or by the small punch creep test. The small punch creep test requires only a small diameter thin disc of material for testing for which its results are comparable with conventional uniaxial creep testing which requires a much larger sample of material. The smaller sample requirement of the small punch creep test therefore allows for a vastly reduced invasive sample retrieval operation and consequently smaller repair size area. Also the fact that the sample is retrieved from a blind hole is advantageous since the pipe wall is not penetrated which would require full plant shutdown. A friction welding technique was identified as an alternative to traditional arc fusion welding for the repair of the sample retrieval site, this technique being the Friction Hydro Pillar Processing technique. Friction Hydro Pillar Processing is a solid-state welding technique and as such has a number of inherent benefits over arc fusion welding as the weld is performed below the melting temperature of the material. From a process point of view Friction Hydro Pillar Processing is ideally suited for automation, has virtually no fumes generated, minimal distortion is experienced and no spatter has to be removed afterwards. The technique has yet to see industrial application and as such development of suitable process parameters was undertaken. Finally, to apply the sample retrieval and repair operations in-situ to a steam pipe in a power plant suitable equipment was developed. Existing friction welding equipment is generally bulky workshop based equipment and is unsuitable for on-site work due to its size and weight. Therefore development of dedicated equipment was required to enable Friction Hydro Pillar Processing to be applied to steam pipes within a power plant environment.
- Full Text:
- Date Issued: 2013
- Authors: Wedderburn, Ian Norman
- Date: 2013
- Subjects: Friction welding
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9635 , http://hdl.handle.net/10948/d1020116
- Description: The remnant life monitoring of creep loaded high temperature and pressure components in power stations is critical to ensuring their safe and cost effective operation as failures can have severe consequences. Effective creep life condition monitoring allows for optimising component life predictions and subsequent plant maintenance decisions. In South Africa many power generation stations have been in operation well beyond their 30 year design service life, as such knowledge of the remnant creep life of high temperature and pressure components, such as steam pipelines, becomes of utmost importance. Techniques for the remnant creep life assessments of critical high temperature and pressure components must therefore be as effective as possible. The common and well accepted in-situ inspection technique for assessing creep damage in steam pipes is by the metallographic replication technique. The technique is however limited to the outer surface of the pipe, without information on damage within the wall. This research will illustrate a means of obtaining a sample for creep life analysis with depth through the wall of a pipe, as wells as an alternative technique for the repair of the sample retrieval site. A sample retrieval technique was developed that would retrieve a small diameter cylindrical sample from a cored blind hole for creep analysis by visual creep void assessment or by the small punch creep test. The small punch creep test requires only a small diameter thin disc of material for testing for which its results are comparable with conventional uniaxial creep testing which requires a much larger sample of material. The smaller sample requirement of the small punch creep test therefore allows for a vastly reduced invasive sample retrieval operation and consequently smaller repair size area. Also the fact that the sample is retrieved from a blind hole is advantageous since the pipe wall is not penetrated which would require full plant shutdown. A friction welding technique was identified as an alternative to traditional arc fusion welding for the repair of the sample retrieval site, this technique being the Friction Hydro Pillar Processing technique. Friction Hydro Pillar Processing is a solid-state welding technique and as such has a number of inherent benefits over arc fusion welding as the weld is performed below the melting temperature of the material. From a process point of view Friction Hydro Pillar Processing is ideally suited for automation, has virtually no fumes generated, minimal distortion is experienced and no spatter has to be removed afterwards. The technique has yet to see industrial application and as such development of suitable process parameters was undertaken. Finally, to apply the sample retrieval and repair operations in-situ to a steam pipe in a power plant suitable equipment was developed. Existing friction welding equipment is generally bulky workshop based equipment and is unsuitable for on-site work due to its size and weight. Therefore development of dedicated equipment was required to enable Friction Hydro Pillar Processing to be applied to steam pipes within a power plant environment.
- Full Text:
- Date Issued: 2013
Competitive strategy implementation in microfinance organisations in Kenya
- Authors: Waweru, Ruth Wambui
- Date: 2013
- Subjects: Microfinance -- Kenya , Financial institutions -- Kenya
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8888 , http://hdl.handle.net/10948/d1020815
- Description: Poverty is a major challenge in most developing countries. Key challenges of the government are to alleviate poverty and propel citizens toward wealth creation through development of enterprises across all sectors and to address the problem of unemployment. In Kenya, the SME sector comprises of about 99% of private sector enterprises and is prolific in employment and wealth creation. Despite this critical role played by SMEs in growing the economy, they remain outside the formal banking sector, especially in Africa. Although the number of MFOs since the 1980s has increased, the demand for financial services is largely unmet. However, MFOs are increasingly experiencing competition from new entrants and commercial banks that have developed financial models to target SMEs. MFOs are required to formulate and implement competitive strategies to enable them achieve sustainable growth and compete with commercial banks. However, strategy implementation is generally accepted as a challenge across organisations and it is often easier to formulate strategies than implementing it. Despite the need to address strategy implementation challenges across organisations, there is a greater focus by practitioners and researchers regarding strategy formulation than implementation. Consequently, this study aimed at assessing the level of strategy implementation in MFOs and factors that affect strategy implementation in MFOs. The ultimate objective was to develop a hypothetical model that could be used to improve strategy implementation in microfinance organisations in Kenya. This quantitative study used purposive sampling to select MFOs that are members of the Association of Microfinance Institutions (AMFI) in Kenya, completing a selfadministered structured questionnaire. In total, 135 MFOs were involved in this study and a total sample size of 300 managers was used in this study. This study considered fourteen factors to have an influence on the level of strategy implementation of MFOs in Kenya and hence fourteen null-hypotheses were formulated and tested. The content factors included stakeholder involvement in strategy development and the quality of strategies. The context factors included organisational structure and culture, strategic leadership and alignment of strategy to market conditions. The operational process factors included operational planning, monitoring and review of progress, teamwork, resources allocation, people-strategy fit, effective communication, strategic and management control systems and information resources. It is assumed that if all these critical strategy implementation factors are addressed, MFOs should be able improve their level of strategy implementation, ultimately leading to improved performance. The outcome factors considered were improved financial sustainability and outreach of MFOs. Advanced statistical analyses were used to analyse the data, such as factor analysis, regression and correlation analysis to assess the hypothesised relationship between the dependent and independent variables of this study. The empirical results revealed that the level of strategy implementation in MFOs in Kenya is moderate to high and content, context and operational factors do have an influence on the level of strategy implementation. However, operational factors have a more significant positive linear relationship with level of strategy implementation than the other two factors. There is also a positive relationship between the level of strategy implementation and financial sustainability and outreach by MFOs. This study has contributed to the existing body of knowledge by developing a hypothetical model that can be utilised by MFOs as well as other organisations to improve the level of strategy implementation resulting in better performance. The findings of the study can also inform strategy formulation and implementation of MFOs in Kenya, but also in other developing countries, to become more competitive. This study could also help MFOs and other organisations to put in place structures, systems, people and other resources required to attain a high level of strategy implementation. This study provides useful and practical guidelines in dealing with content, context and operational factors affecting strategy implementation in any organisational setting.
- Full Text:
- Date Issued: 2013
- Authors: Waweru, Ruth Wambui
- Date: 2013
- Subjects: Microfinance -- Kenya , Financial institutions -- Kenya
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8888 , http://hdl.handle.net/10948/d1020815
- Description: Poverty is a major challenge in most developing countries. Key challenges of the government are to alleviate poverty and propel citizens toward wealth creation through development of enterprises across all sectors and to address the problem of unemployment. In Kenya, the SME sector comprises of about 99% of private sector enterprises and is prolific in employment and wealth creation. Despite this critical role played by SMEs in growing the economy, they remain outside the formal banking sector, especially in Africa. Although the number of MFOs since the 1980s has increased, the demand for financial services is largely unmet. However, MFOs are increasingly experiencing competition from new entrants and commercial banks that have developed financial models to target SMEs. MFOs are required to formulate and implement competitive strategies to enable them achieve sustainable growth and compete with commercial banks. However, strategy implementation is generally accepted as a challenge across organisations and it is often easier to formulate strategies than implementing it. Despite the need to address strategy implementation challenges across organisations, there is a greater focus by practitioners and researchers regarding strategy formulation than implementation. Consequently, this study aimed at assessing the level of strategy implementation in MFOs and factors that affect strategy implementation in MFOs. The ultimate objective was to develop a hypothetical model that could be used to improve strategy implementation in microfinance organisations in Kenya. This quantitative study used purposive sampling to select MFOs that are members of the Association of Microfinance Institutions (AMFI) in Kenya, completing a selfadministered structured questionnaire. In total, 135 MFOs were involved in this study and a total sample size of 300 managers was used in this study. This study considered fourteen factors to have an influence on the level of strategy implementation of MFOs in Kenya and hence fourteen null-hypotheses were formulated and tested. The content factors included stakeholder involvement in strategy development and the quality of strategies. The context factors included organisational structure and culture, strategic leadership and alignment of strategy to market conditions. The operational process factors included operational planning, monitoring and review of progress, teamwork, resources allocation, people-strategy fit, effective communication, strategic and management control systems and information resources. It is assumed that if all these critical strategy implementation factors are addressed, MFOs should be able improve their level of strategy implementation, ultimately leading to improved performance. The outcome factors considered were improved financial sustainability and outreach of MFOs. Advanced statistical analyses were used to analyse the data, such as factor analysis, regression and correlation analysis to assess the hypothesised relationship between the dependent and independent variables of this study. The empirical results revealed that the level of strategy implementation in MFOs in Kenya is moderate to high and content, context and operational factors do have an influence on the level of strategy implementation. However, operational factors have a more significant positive linear relationship with level of strategy implementation than the other two factors. There is also a positive relationship between the level of strategy implementation and financial sustainability and outreach by MFOs. This study has contributed to the existing body of knowledge by developing a hypothetical model that can be utilised by MFOs as well as other organisations to improve the level of strategy implementation resulting in better performance. The findings of the study can also inform strategy formulation and implementation of MFOs in Kenya, but also in other developing countries, to become more competitive. This study could also help MFOs and other organisations to put in place structures, systems, people and other resources required to attain a high level of strategy implementation. This study provides useful and practical guidelines in dealing with content, context and operational factors affecting strategy implementation in any organisational setting.
- Full Text:
- Date Issued: 2013
Process heat flow model for temperature and hardness prediction during friction taper stud welding of AISI 4140
- Van Zyl, Carlo Angelo Antonio
- Authors: Van Zyl, Carlo Angelo Antonio
- Date: 2013
- Subjects: Friction welding Pressure welding
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/47780 , vital:40373
- Description: Friction Taper Stud Welding (FTSW) is a relatively new solid state welding process, developed from the concepts of friction welding, which theoretically operates below the melting temperatures of the material being welded. During friction welding, heat is generated by conversion of mechanical energy into thermal energy at the interface of the work pieces, during rotation under pressure. Quality welds are dependant on the correct selection of welding process parameters, which are currently chosen empirically, and the FTSW evaluated by mechanical testing. This method is time consuming, uneconomical and could cause that optimised conditions are overlooked. A proposed solution would be to numerically model the process, but reference to successful computational modelling of the FTSW process is currently not available and data regarding the responses during the process are limited. The ultimate aim of the present study is to develop a finite element model to simulate the FTSW process using AISI 4140 medium carbon low alloy steel, delivering temperature profiles and hardness predictions through the Heat Affected Zone (HAZ) – using a combined experimental and numerical study. To achieve the objectives of this study a systematic approach was adopted and conducted in several phases. A weld matrix was configured with ranging weld input parameters to determine the affect of weld input parameters on real-time responses. To provide a relationship between these factors, welding was conducted using a portable friction taper stud welding platform linked to a control and data logging system for measuring the real time axial forces, spindle speed, material displacement, torque and temperature responses as a function of time. The input process parameters applied being motor speed, axial forces, displacement and forging time. The temperature distribution through the weld, by direct measurement, as a function of weld time and position is investigated. During the experimental welds temperature responses, as influenced by welding parameters, were recorded using embedded N-Type thermocouples at various locations in the near vicinity of the weld interface. The main hot spots during welding were identified to be close to the top surface just before weld completion and at the bottom centre surface of the plug weld at the interface line. All the welds showed similar trends and a maximum temperature of 1078°C at the bottom of the weld was reached for a rotational tool speed of 5160rpm, axial friction force of 15kN and displacement of 6.5mm, due to the heat generated by friction between the tool and weld coupon. The weld torque increase rapidly at the start of the weld and reached a peak value shortly after the start of the weld, while a peak temperature of 1366°C, for a rotational tool speed of 5160rpm, axial friction force of 10kN and displacement of 8mm was reached at the top edge of the plug weld. This position of anticipated peak temperature value is due to the heat transferred during the FTSW process together with the accumulation of expelled material forming on the surface of the weld coupon. Statistical methods were applied to obtain knowledge of the trends and relationship between weld input parameters for various weld responses, including energy input, temperature, friction time, torque and displacement rate. Although it was shown that no single parameter solely controls the temperature gradients in the weld, the dominant influence of the rotational speed at the bottom of the weld and that of the displacement, at the top of the weld, were evident. The peak temperatures during the weld are of interest as these temperatures, together with the subsequent cooling rates, determine the Vickers hardness, of the material, through the weld. Spindle speed was found to have the dominant effect on temperature in the bottom half of the weld with displacement having a contributive effect closer to the top of the weld. Friction force dominate the effect on friction time, displacement rate and total energy input with friction force and spindle speed having an equal effect on torque. The multiple regression analysis resulted in valid models with varied, but acceptable accuracy with the equation for friction time resulting in an R predict value of 93.34%. These models provided a clear insight to the influence of weld input parameters on the weld responses and the model for friction time was used as an input parameter to the FTS welding simulation. The accurate prediction of the interface temperature is fundamental for process optimisation which will allow for producing consistent, reliable plug welds. A fully coupled transient two-dimensional axi-symmetrical analysis of heat flow during the FTSW process of AISI 4140 steel and subsequent Vickers hardness profiles through the HAZ, making use of numeric simulation applied in the commercially available FEA software, COMSOL Multiphysics®, is developed and reported on. Process optimisation hinges on a better understanding of the heat distribution during welding, making a major contribution to the resultant hardness. The thermal-plastic flow coupling of the model is such that temperature values are resolved together with that of the velocity field. The simulation utilises a Computational Fluid Dynamics (CFD) two phase laminar flow and Heat Transfer physics, applied in an Eulerian mesh-based scheme. The viscosity of the fluid is based on a constitutive law of the flow stress using the Zener-Hollomon parameter with a flow model based on the Navier-Stokes’ equations to simulate the plastic deformation. Temperature dependant thermo-physical material properties and coefficient of friction are applied, and the application of viscous heating is controlled by a material state variable. The heat source model, required for material softening, is applied as two components, frictional and shear, with the heat source moving along the z-axis delivering sufficient energy to soften the metal, causing flow. The Navier-Stokes approach is applied with solid-state material transport during the weld based on laminar, viscous flow of a non-Newtonian fluid, dependant on temperature and strain rate. Numerically calculated values for temperature profiles and peak temperatures through to the weld as well as subsequent Vickers hardness profiles at points through the HAZ, obtained from the Finite Element model, were found to be in close agreement with values from trial welds. The largest variance was 19% for the peak temperature of weld E4W2, applying an axial friction force of 7.5kN, 6.5mm displacement and a tool rotational speed of 4080rpm – resulting in a friction time of 330 seconds. Predictions of hardness are found to be between 0% and 19% (mean 3%) of experimentally determined values with the biggest variance at the positions of peak temperatures due to the friction interfaces. The heat applied as a result of plastic deformation was found to be 5.4% of the total heat. The FTSW model predicts the temperatures at the friction interface, during the welding process, to be within the range, and frequently exceeding the solidus temperature of AISI 4140 steel. Results show that the models applied in the FTSW simulation show good agreement when compared to experimental values. The main contribution of this thesis, towards knowledge of the FTSW process, is: The relationships between weld input parameters and responses; Temperature dependant models of thermo-physical properties for AISI 4140 in the high temperature region (ranging from ambient to the solidus temperature); Successful application of the Navier-Stokes approach to simulate the plastic flow during FTSW and A numerical finite element model for the prediction of temperature gradients and hardness profiles through a FTSW.
- Full Text:
- Date Issued: 2013
- Authors: Van Zyl, Carlo Angelo Antonio
- Date: 2013
- Subjects: Friction welding Pressure welding
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/47780 , vital:40373
- Description: Friction Taper Stud Welding (FTSW) is a relatively new solid state welding process, developed from the concepts of friction welding, which theoretically operates below the melting temperatures of the material being welded. During friction welding, heat is generated by conversion of mechanical energy into thermal energy at the interface of the work pieces, during rotation under pressure. Quality welds are dependant on the correct selection of welding process parameters, which are currently chosen empirically, and the FTSW evaluated by mechanical testing. This method is time consuming, uneconomical and could cause that optimised conditions are overlooked. A proposed solution would be to numerically model the process, but reference to successful computational modelling of the FTSW process is currently not available and data regarding the responses during the process are limited. The ultimate aim of the present study is to develop a finite element model to simulate the FTSW process using AISI 4140 medium carbon low alloy steel, delivering temperature profiles and hardness predictions through the Heat Affected Zone (HAZ) – using a combined experimental and numerical study. To achieve the objectives of this study a systematic approach was adopted and conducted in several phases. A weld matrix was configured with ranging weld input parameters to determine the affect of weld input parameters on real-time responses. To provide a relationship between these factors, welding was conducted using a portable friction taper stud welding platform linked to a control and data logging system for measuring the real time axial forces, spindle speed, material displacement, torque and temperature responses as a function of time. The input process parameters applied being motor speed, axial forces, displacement and forging time. The temperature distribution through the weld, by direct measurement, as a function of weld time and position is investigated. During the experimental welds temperature responses, as influenced by welding parameters, were recorded using embedded N-Type thermocouples at various locations in the near vicinity of the weld interface. The main hot spots during welding were identified to be close to the top surface just before weld completion and at the bottom centre surface of the plug weld at the interface line. All the welds showed similar trends and a maximum temperature of 1078°C at the bottom of the weld was reached for a rotational tool speed of 5160rpm, axial friction force of 15kN and displacement of 6.5mm, due to the heat generated by friction between the tool and weld coupon. The weld torque increase rapidly at the start of the weld and reached a peak value shortly after the start of the weld, while a peak temperature of 1366°C, for a rotational tool speed of 5160rpm, axial friction force of 10kN and displacement of 8mm was reached at the top edge of the plug weld. This position of anticipated peak temperature value is due to the heat transferred during the FTSW process together with the accumulation of expelled material forming on the surface of the weld coupon. Statistical methods were applied to obtain knowledge of the trends and relationship between weld input parameters for various weld responses, including energy input, temperature, friction time, torque and displacement rate. Although it was shown that no single parameter solely controls the temperature gradients in the weld, the dominant influence of the rotational speed at the bottom of the weld and that of the displacement, at the top of the weld, were evident. The peak temperatures during the weld are of interest as these temperatures, together with the subsequent cooling rates, determine the Vickers hardness, of the material, through the weld. Spindle speed was found to have the dominant effect on temperature in the bottom half of the weld with displacement having a contributive effect closer to the top of the weld. Friction force dominate the effect on friction time, displacement rate and total energy input with friction force and spindle speed having an equal effect on torque. The multiple regression analysis resulted in valid models with varied, but acceptable accuracy with the equation for friction time resulting in an R predict value of 93.34%. These models provided a clear insight to the influence of weld input parameters on the weld responses and the model for friction time was used as an input parameter to the FTS welding simulation. The accurate prediction of the interface temperature is fundamental for process optimisation which will allow for producing consistent, reliable plug welds. A fully coupled transient two-dimensional axi-symmetrical analysis of heat flow during the FTSW process of AISI 4140 steel and subsequent Vickers hardness profiles through the HAZ, making use of numeric simulation applied in the commercially available FEA software, COMSOL Multiphysics®, is developed and reported on. Process optimisation hinges on a better understanding of the heat distribution during welding, making a major contribution to the resultant hardness. The thermal-plastic flow coupling of the model is such that temperature values are resolved together with that of the velocity field. The simulation utilises a Computational Fluid Dynamics (CFD) two phase laminar flow and Heat Transfer physics, applied in an Eulerian mesh-based scheme. The viscosity of the fluid is based on a constitutive law of the flow stress using the Zener-Hollomon parameter with a flow model based on the Navier-Stokes’ equations to simulate the plastic deformation. Temperature dependant thermo-physical material properties and coefficient of friction are applied, and the application of viscous heating is controlled by a material state variable. The heat source model, required for material softening, is applied as two components, frictional and shear, with the heat source moving along the z-axis delivering sufficient energy to soften the metal, causing flow. The Navier-Stokes approach is applied with solid-state material transport during the weld based on laminar, viscous flow of a non-Newtonian fluid, dependant on temperature and strain rate. Numerically calculated values for temperature profiles and peak temperatures through to the weld as well as subsequent Vickers hardness profiles at points through the HAZ, obtained from the Finite Element model, were found to be in close agreement with values from trial welds. The largest variance was 19% for the peak temperature of weld E4W2, applying an axial friction force of 7.5kN, 6.5mm displacement and a tool rotational speed of 4080rpm – resulting in a friction time of 330 seconds. Predictions of hardness are found to be between 0% and 19% (mean 3%) of experimentally determined values with the biggest variance at the positions of peak temperatures due to the friction interfaces. The heat applied as a result of plastic deformation was found to be 5.4% of the total heat. The FTSW model predicts the temperatures at the friction interface, during the welding process, to be within the range, and frequently exceeding the solidus temperature of AISI 4140 steel. Results show that the models applied in the FTSW simulation show good agreement when compared to experimental values. The main contribution of this thesis, towards knowledge of the FTSW process, is: The relationships between weld input parameters and responses; Temperature dependant models of thermo-physical properties for AISI 4140 in the high temperature region (ranging from ambient to the solidus temperature); Successful application of the Navier-Stokes approach to simulate the plastic flow during FTSW and A numerical finite element model for the prediction of temperature gradients and hardness profiles through a FTSW.
- Full Text:
- Date Issued: 2013
Numerical relativity on cosmological past null cones
- Van der Walt, Petrus Johannes
- Authors: Van der Walt, Petrus Johannes
- Date: 2013
- Subjects: Cosmology Numerical calculations General relativity (Physics) -- Mathematics Einstein field equations Gravity Gravitational waves Horizon
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5396 , http://hdl.handle.net/10962/d1002959
- Description: The observational approach to cosmology is the endeavour to reconstruct the geometry of the Universe using only data that is theoretically verifiable within the causal boundaries of a cosmological observer. Using this approach, it was shown in [36] that given ideal cosmological observations, the only essential assumption necessary to determine the geometry of the Universe is a theory of gravity. Assuming General Relativity, the full set of Einstein field equations (EFEs) can be used to reconstruct the geometry of the Universe using direct observations on the past null cone (PNC) as initial conditions. Observationally and theoretically this is a very ambitious task and therefore, current developments have been restricted to spherically symmetric dust models while only relaxing the usual assumption of homogeneity in the radial direction. These restricted models are important for the development of theoretical foundations and also useful as verification models since they avoid the circularity of verifying what has already been assumed. The work presented in this thesis is the development of such a model where numerical relativity (NR) is used to simulate the observable universe. Similar to the work of Ellis and co-workers [36], a reference frame based on the PNC is used. The reference frame used here, however, is based on that of the characteristic formalism of NR, which has developed for calculating the propagation of gravitational waves. This provides a formalism that is well established in NR, making the use of existing algorithms possible. The Bondi-Sachs coordinates of the characteristic formalism is, however, not suitable for calculations beyond the observer apparent horizon (AH) since the diameter distance used as a radial coordinate becomes multi-valued when the cosmological PNC reconverges in the history of a universe, smaller in the past. With this taken into consideration, the Bondi-Sachs characteristic formalism is implemented for cosmology and the problem approaching the AH is investigated. Further developments address the limitations approaching the AH by introducing a metric based on the Bondi-Sachs metric where the radial coordinate is replaced with an affine parameter. The model is derived with a cosmological constant Λ incorporated into the EFEs where Λ is taken as a parameter of the theory of gravity rather than as a matter source term. Similar to the conventional characteristic formalism, this model consists of a system of differential equations for numerically evolving the EFEs as a characteristic initial value problem (CIVP). A numerical code implemented for the method has been found to be second order convergent. This code enables simulations of different models given identical data on the initial null cone and provides a method to investigate their physical consistency within the causally connected region of our current PNC. These developments closely follow existing 3D schemes developed for gravitational wave simulations, which should make it natural to extend the affine CIVP beyond spherical symmetric simulations. The developments presented in this thesis is an extended version of two papers published earlier.
- Full Text:
- Date Issued: 2013
- Authors: Van der Walt, Petrus Johannes
- Date: 2013
- Subjects: Cosmology Numerical calculations General relativity (Physics) -- Mathematics Einstein field equations Gravity Gravitational waves Horizon
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5396 , http://hdl.handle.net/10962/d1002959
- Description: The observational approach to cosmology is the endeavour to reconstruct the geometry of the Universe using only data that is theoretically verifiable within the causal boundaries of a cosmological observer. Using this approach, it was shown in [36] that given ideal cosmological observations, the only essential assumption necessary to determine the geometry of the Universe is a theory of gravity. Assuming General Relativity, the full set of Einstein field equations (EFEs) can be used to reconstruct the geometry of the Universe using direct observations on the past null cone (PNC) as initial conditions. Observationally and theoretically this is a very ambitious task and therefore, current developments have been restricted to spherically symmetric dust models while only relaxing the usual assumption of homogeneity in the radial direction. These restricted models are important for the development of theoretical foundations and also useful as verification models since they avoid the circularity of verifying what has already been assumed. The work presented in this thesis is the development of such a model where numerical relativity (NR) is used to simulate the observable universe. Similar to the work of Ellis and co-workers [36], a reference frame based on the PNC is used. The reference frame used here, however, is based on that of the characteristic formalism of NR, which has developed for calculating the propagation of gravitational waves. This provides a formalism that is well established in NR, making the use of existing algorithms possible. The Bondi-Sachs coordinates of the characteristic formalism is, however, not suitable for calculations beyond the observer apparent horizon (AH) since the diameter distance used as a radial coordinate becomes multi-valued when the cosmological PNC reconverges in the history of a universe, smaller in the past. With this taken into consideration, the Bondi-Sachs characteristic formalism is implemented for cosmology and the problem approaching the AH is investigated. Further developments address the limitations approaching the AH by introducing a metric based on the Bondi-Sachs metric where the radial coordinate is replaced with an affine parameter. The model is derived with a cosmological constant Λ incorporated into the EFEs where Λ is taken as a parameter of the theory of gravity rather than as a matter source term. Similar to the conventional characteristic formalism, this model consists of a system of differential equations for numerically evolving the EFEs as a characteristic initial value problem (CIVP). A numerical code implemented for the method has been found to be second order convergent. This code enables simulations of different models given identical data on the initial null cone and provides a method to investigate their physical consistency within the causally connected region of our current PNC. These developments closely follow existing 3D schemes developed for gravitational wave simulations, which should make it natural to extend the affine CIVP beyond spherical symmetric simulations. The developments presented in this thesis is an extended version of two papers published earlier.
- Full Text:
- Date Issued: 2013
Positions on the mat : a micro-ethnographic study of teachers' and learners' co-construction of an early literacy practice
- Authors: Van der Mescht, Caroline
- Date: 2013 , 2013-06-10
- Subjects: Literacy -- Study and teaching (Primary) -- South Africa -- Eastern Cape English language -- Study and teaching (Primary) -- South Africa -- Eastern Cape English literature -- Study and teaching (Primary) -- South Africa -- Eastern Cape Education, Primary -- Research -- South Africa -- Eastern Cape Teachers -- Psychology Language and culture
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1836 , http://hdl.handle.net/10962/d1004333
- Description: Thesis embargoed until end of 2023. , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
- Authors: Van der Mescht, Caroline
- Date: 2013 , 2013-06-10
- Subjects: Literacy -- Study and teaching (Primary) -- South Africa -- Eastern Cape English language -- Study and teaching (Primary) -- South Africa -- Eastern Cape English literature -- Study and teaching (Primary) -- South Africa -- Eastern Cape Education, Primary -- Research -- South Africa -- Eastern Cape Teachers -- Psychology Language and culture
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:1836 , http://hdl.handle.net/10962/d1004333
- Description: Thesis embargoed until end of 2023. , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
GDR development policy with special reference to Africa, c. 1960-1990
- Van der Heyden, Ulrich Klaus Helmut
- Authors: Van der Heyden, Ulrich Klaus Helmut
- Date: 2013
- Subjects: Germany -- Foreign relations -- Africa , Germany -- Foreign economic relations -- Africa , Africa -- Foreign relations -- Germany , Africa -- Foreign economic relations -- Germany , Africa -- Politics and government -- 1960- , Africa -- History -- 1960-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2531 , http://hdl.handle.net/10962/d1001860
- Description: This thesis explores the political, economic and theoretical underpinnings of the German Democratic Republic’s (GDR’s) development policies towards the Third World between c.1960 and 1990. Particular attention is paid to Africa. Case studies of assistance to SWAPO and the ANC further focus the attention of the reader on southern Africa in particular. Aspects of both military and civilian aid are considered, including both development initiatives overseas in Africa, and development training for Africans within the GDR itself. Since German “reunification”, the GDR’s history has been explored largely from a West German perspective. The present work attempts to provide a more balanced view of successes and shortcomings of the GDR’s policies towards, and interaction with, African countries and liberation movements. It also aims to bring to the attention of English-speaking readers German archival sources, other primary sources and published works which they would otherwise have been unlikely to encounter. From its formation, the GDR made strenuous efforts to develop relations with countries which were either free from colonial dependency or were struggling for freedom. Over the course of thirty years, it followed a number of different approaches, and developed diverse objectives. These were shaped in the wider context of the cold war, the Hallstein doctrine (which established that the FRG – and, in effect, its allies - would not establish or maintain diplomatic relations with any state that recognised the GDR), the relationships between the GDR and partner socialist states, and the economic difficulties faced by the GDR. Arising from this complex situation, from time to time, both internally in the GDR and in terms of its foreign affairs, tensions and discrepancies arose between theoretical objectives and political and economic reality. Despite these severe constraints, during the period under review, the volume and range of the GDR’s relationships with developing countries increased dramatically. For example, between 1970 and 1987, the number of developing countries with which the GDR had foreign economic relations on the basis of international agreements grew from 23 to 64. Viewed within its economic context, the state was arguably far more committed to development aid than the Federal Republic of Germany. In addition, there is a great deal of evidence that “solidarity” with developing nations and the oppressed enjoyed a considerable degree of popular support.
- Full Text:
- Date Issued: 2013
- Authors: Van der Heyden, Ulrich Klaus Helmut
- Date: 2013
- Subjects: Germany -- Foreign relations -- Africa , Germany -- Foreign economic relations -- Africa , Africa -- Foreign relations -- Germany , Africa -- Foreign economic relations -- Germany , Africa -- Politics and government -- 1960- , Africa -- History -- 1960-
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2531 , http://hdl.handle.net/10962/d1001860
- Description: This thesis explores the political, economic and theoretical underpinnings of the German Democratic Republic’s (GDR’s) development policies towards the Third World between c.1960 and 1990. Particular attention is paid to Africa. Case studies of assistance to SWAPO and the ANC further focus the attention of the reader on southern Africa in particular. Aspects of both military and civilian aid are considered, including both development initiatives overseas in Africa, and development training for Africans within the GDR itself. Since German “reunification”, the GDR’s history has been explored largely from a West German perspective. The present work attempts to provide a more balanced view of successes and shortcomings of the GDR’s policies towards, and interaction with, African countries and liberation movements. It also aims to bring to the attention of English-speaking readers German archival sources, other primary sources and published works which they would otherwise have been unlikely to encounter. From its formation, the GDR made strenuous efforts to develop relations with countries which were either free from colonial dependency or were struggling for freedom. Over the course of thirty years, it followed a number of different approaches, and developed diverse objectives. These were shaped in the wider context of the cold war, the Hallstein doctrine (which established that the FRG – and, in effect, its allies - would not establish or maintain diplomatic relations with any state that recognised the GDR), the relationships between the GDR and partner socialist states, and the economic difficulties faced by the GDR. Arising from this complex situation, from time to time, both internally in the GDR and in terms of its foreign affairs, tensions and discrepancies arose between theoretical objectives and political and economic reality. Despite these severe constraints, during the period under review, the volume and range of the GDR’s relationships with developing countries increased dramatically. For example, between 1970 and 1987, the number of developing countries with which the GDR had foreign economic relations on the basis of international agreements grew from 23 to 64. Viewed within its economic context, the state was arguably far more committed to development aid than the Federal Republic of Germany. In addition, there is a great deal of evidence that “solidarity” with developing nations and the oppressed enjoyed a considerable degree of popular support.
- Full Text:
- Date Issued: 2013
A framework for biometrics for social grants in South Africa
- Authors: Van de Haar, Helen Augusta
- Date: 2013
- Subjects: Biometric identification -- Law and legislation -- South Africa , Biometric identification cards -- South Africa , Public welfare -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9829 , http://hdl.handle.net/10948/d1021018
- Description: In the South African Social Security Agency (SASSA) Annual Report of 2011/2012 it is stated that there were more than 15 million social grants paid out to needy beneficiaries of which 10 927 731 were Child Support Grants. A major challenge that is continually being addressed is the management and administration of these grants. In particular, the focus is on service delivery and zero tolerance to fraud and corruption. SASSA has made various attempts to address these issues, such as the rollout of biometric smart cards in 2012. This research endeavour attempts to discover whether a framework can be designed where necessary factors are taken into consideration to provide for an efficient social grant application and delivery process that uses biometrics. The framework aims to suggest improvements in the use of biometrics for the social grants. Seeing that biometrics in this case is used as a technology to improve a system involving humans, this study followed a Design Science approach and made use of a case study to collect the data required for the study. Literature studies reviewed the fields of social grants and biometrics. The challenges and lessons learnt from current implementations of social grants and biometrics within the South African context and further abroad were also relevant for the study. The framework that resulted from the above was evaluated for validity and applicability after which a modified framework is presented. The research concludes with specific implementation guidelines as well as areas for future research.
- Full Text:
- Date Issued: 2013
- Authors: Van de Haar, Helen Augusta
- Date: 2013
- Subjects: Biometric identification -- Law and legislation -- South Africa , Biometric identification cards -- South Africa , Public welfare -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9829 , http://hdl.handle.net/10948/d1021018
- Description: In the South African Social Security Agency (SASSA) Annual Report of 2011/2012 it is stated that there were more than 15 million social grants paid out to needy beneficiaries of which 10 927 731 were Child Support Grants. A major challenge that is continually being addressed is the management and administration of these grants. In particular, the focus is on service delivery and zero tolerance to fraud and corruption. SASSA has made various attempts to address these issues, such as the rollout of biometric smart cards in 2012. This research endeavour attempts to discover whether a framework can be designed where necessary factors are taken into consideration to provide for an efficient social grant application and delivery process that uses biometrics. The framework aims to suggest improvements in the use of biometrics for the social grants. Seeing that biometrics in this case is used as a technology to improve a system involving humans, this study followed a Design Science approach and made use of a case study to collect the data required for the study. Literature studies reviewed the fields of social grants and biometrics. The challenges and lessons learnt from current implementations of social grants and biometrics within the South African context and further abroad were also relevant for the study. The framework that resulted from the above was evaluated for validity and applicability after which a modified framework is presented. The research concludes with specific implementation guidelines as well as areas for future research.
- Full Text:
- Date Issued: 2013
The influence of overwash and breaching events on the spatial and temporal patterns in ichthyofauna community composition in a temporarily open/closed southern African estuary
- Authors: Tweddle, Gavin Paul
- Date: 2013
- Subjects: Estuarine fishes -- Africa, Southern Marine fishes -- Africa, Southern Fishes -- Breeding -- Africa, Southern Fishes -- Effect of habitat modification on -- Africa, Southern Fishes -- Spawning -- Africa, Southern Gobiidae -- Africa, Southern Estuaries -- Africa, Southern Estuarine ecology -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5610 , http://hdl.handle.net/10962/d1002957
- Description: This study assessed the importance of overwash and breaching events on the ichthyofaunal community structure in the medium-sized temporarily open/closed Mpekweni Estuary located on the southeast coastline of southern Africa. The fish in the littoral zone of the estuary were sampled using a 5m seine net while the channel region was sampled using two nets, a smaller meshed 30m seine net to target the estuarine spawning species and the juvenile estuarine-dependant marine spawners, and a larger meshed 50m seine net to target the larger marine and freshwater spawning species. Intensive monthly sampling over two years provided data on selected physico-chemical and biological parameters. During the two year sampling period from November 2005 to October 2007 the estuary breached in late July 2006 and remained open till the sandbar re-formed across the mouth in late December 2006. Thus, sampling encompassed three open/closed phases 1) initial closed period, 2) open period and 3) re-closed period after the berm was re-formed. The open period was divided into two phases 1) the out-flow phase and 2) the tidal phase. A total of 36 fish species representing 19 families were sampled using the various seine nets employed during the investigation. In the littoral zone, the estuarine spawners (Estuarine Utilisation Category, [EUC] I), mainly the Gobiidae, Glossogobius callidus, dominated the samples numerically and by biomass. The smaller estuarine spawning species sampled in the channel were numerically dominated by Gilchristella aestuaria in conjunction with two other EUC I species, Atherina breviceps and G. callidus. The estuarine-dependant marine spawners (EUC II), however, dominated the ichthyofaunal biomass of the channel. The abundance and biomass of the larger species targeted were dominated by estuarine-dependant marine spawning species (EUC II), principally Rhabdosargus holubi. During the closed periods of the estuary, total fish abundance and biomass displayed weak seasonal patterns. The breaching event and subsequent open period was associated with a decrease in the total abundances of fish in the littoral zone and channel of the estuary, reflecting the out-flow of estuarine biomass-rich water into the marine environment. The breaching event coincided with a shift in the community composition of the ichthyofauna, reflecting the recruitment of marine spawning species into the estuary. Numerical analysis identified two distinct spatial fish communities within the estuary, a community associated with the mouth region and one comprising the rest of the estuary. The absence of any further spatial patterns in the ichthyofaunal community structure within the Mpekweni Estuary appear to be ascribed to the virtual absence of horizontal patterns in physico-chemical and biological parameters recorded in the system. Cohort analyses were employed to determine possible recruitment events for selected estuarine and marine spawning species. The estuarine spawning species displayed continuous recruitment patterns throughout the study, which appeared to be unaffected by the breaching event. Conversely, the larger marine spawning species displayed multiple cohorts, indicating non-continuous recruitment. Subsequent retrospective analysis of cohorts for the different species identified summer recruitment peaks that coincided with the breaching event and open period. Minor recruitment of marine spawning species also occurred during overwash events. The recruitment of ichthyofauna into the estuary was quantified during three distinct hydrological events: overwash, out-flow phase immediately after breaching and tidal phase during the period when the mouth was open. Estimates of fish recruitment were highest during the outflow phase immediately after the estuary breached and declined as the estuary became tidally inundated with marine water. Although not as high as the outflow and tidal phases, recruitment was evident during overwash events. Results of the current study highlight the importance of both breaching and overwashing events in structuring the ichthyofaunal community composition in a medium-sized southern African temporarily open/closed estuary. These results are broadly in agreement with similar studies conducted both locally and in other regions of the world.
- Full Text:
- Date Issued: 2013
- Authors: Tweddle, Gavin Paul
- Date: 2013
- Subjects: Estuarine fishes -- Africa, Southern Marine fishes -- Africa, Southern Fishes -- Breeding -- Africa, Southern Fishes -- Effect of habitat modification on -- Africa, Southern Fishes -- Spawning -- Africa, Southern Gobiidae -- Africa, Southern Estuaries -- Africa, Southern Estuarine ecology -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5610 , http://hdl.handle.net/10962/d1002957
- Description: This study assessed the importance of overwash and breaching events on the ichthyofaunal community structure in the medium-sized temporarily open/closed Mpekweni Estuary located on the southeast coastline of southern Africa. The fish in the littoral zone of the estuary were sampled using a 5m seine net while the channel region was sampled using two nets, a smaller meshed 30m seine net to target the estuarine spawning species and the juvenile estuarine-dependant marine spawners, and a larger meshed 50m seine net to target the larger marine and freshwater spawning species. Intensive monthly sampling over two years provided data on selected physico-chemical and biological parameters. During the two year sampling period from November 2005 to October 2007 the estuary breached in late July 2006 and remained open till the sandbar re-formed across the mouth in late December 2006. Thus, sampling encompassed three open/closed phases 1) initial closed period, 2) open period and 3) re-closed period after the berm was re-formed. The open period was divided into two phases 1) the out-flow phase and 2) the tidal phase. A total of 36 fish species representing 19 families were sampled using the various seine nets employed during the investigation. In the littoral zone, the estuarine spawners (Estuarine Utilisation Category, [EUC] I), mainly the Gobiidae, Glossogobius callidus, dominated the samples numerically and by biomass. The smaller estuarine spawning species sampled in the channel were numerically dominated by Gilchristella aestuaria in conjunction with two other EUC I species, Atherina breviceps and G. callidus. The estuarine-dependant marine spawners (EUC II), however, dominated the ichthyofaunal biomass of the channel. The abundance and biomass of the larger species targeted were dominated by estuarine-dependant marine spawning species (EUC II), principally Rhabdosargus holubi. During the closed periods of the estuary, total fish abundance and biomass displayed weak seasonal patterns. The breaching event and subsequent open period was associated with a decrease in the total abundances of fish in the littoral zone and channel of the estuary, reflecting the out-flow of estuarine biomass-rich water into the marine environment. The breaching event coincided with a shift in the community composition of the ichthyofauna, reflecting the recruitment of marine spawning species into the estuary. Numerical analysis identified two distinct spatial fish communities within the estuary, a community associated with the mouth region and one comprising the rest of the estuary. The absence of any further spatial patterns in the ichthyofaunal community structure within the Mpekweni Estuary appear to be ascribed to the virtual absence of horizontal patterns in physico-chemical and biological parameters recorded in the system. Cohort analyses were employed to determine possible recruitment events for selected estuarine and marine spawning species. The estuarine spawning species displayed continuous recruitment patterns throughout the study, which appeared to be unaffected by the breaching event. Conversely, the larger marine spawning species displayed multiple cohorts, indicating non-continuous recruitment. Subsequent retrospective analysis of cohorts for the different species identified summer recruitment peaks that coincided with the breaching event and open period. Minor recruitment of marine spawning species also occurred during overwash events. The recruitment of ichthyofauna into the estuary was quantified during three distinct hydrological events: overwash, out-flow phase immediately after breaching and tidal phase during the period when the mouth was open. Estimates of fish recruitment were highest during the outflow phase immediately after the estuary breached and declined as the estuary became tidally inundated with marine water. Although not as high as the outflow and tidal phases, recruitment was evident during overwash events. Results of the current study highlight the importance of both breaching and overwashing events in structuring the ichthyofaunal community composition in a medium-sized southern African temporarily open/closed estuary. These results are broadly in agreement with similar studies conducted both locally and in other regions of the world.
- Full Text:
- Date Issued: 2013
An investigation of skills, knowledge and farmer support programmes of land reform beneficiaries :a case study of Forest Hill farmers in Kenton-on-Sea in the Ndlambe Local Municipality
- Authors: Tshuma, Mengezi Chancellor
- Date: 2013
- Subjects: Land reforms -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Agricultural Economics)
- Identifier: vital:11205 , http://hdl.handle.net/10353/d1013109 , Land reforms -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Description: black owners by white colonialists. Even though whites made up less than 20% of the nation‟s population, they took more than 80% of the agriculturally productive land and drove the original owners to the unproductive reserves where they were cramped and could not practice agriculture at all. Various acts such as the Black Land Act of 1913, Development Trust Act of 1936 and the Native Laws Amendment Act of 1937 were introduced which further frustrated the displaced black population thereby plunging it deeper and deeper into poverty. The main objective behind the introduction of these acts was to restrain the black population from earning livelihoods through agriculture thus forcing them to offer their labour to white farmers for low wages just to earn some form of livelihood. Such unfair practices and distribution of land prompted the first democratically elected government of South Africa to embark on a drive to redistribute the nation‟s land equitably amongst its citizens to foster national reconciliation, stimulate economic growth and compensate those that were forced out or lost their land during the apartheid era. This initiative was called the Land Reform Programme (LRP) and was implemented with three prongs namely (i) land redistribution; (ii) restitution; and (iii) land tenure. Among the beneficiaries of the LRP were farmers from a community called Marselle in Kenton-on-sea. In addition to getting land for farming purposes, the Marselle farmers also obtained financial support from the government‟s Land Bank to help them kick-start their farming activities. However, in spite of such interventions, they have struggled to turn their activities into sustainable livelihood sources. One most likely cause for this is the lack of farming knowledge and skills needed to make them more efficient and productive. This study was thus geared towards evaluating the knowledge and skills gap in Marselle which, when addressed, could make the Marselle farmers more productive. Its focus was limited to the 32 livestock and 8 chicory farmers that are recognized members of their respective projects. Focus was limited only to these farmers since the next phase of this study will involve building their capacity based on the skills gaps identified through this study. The findings showed that the two projects benefited at least 130 individuals belonging to the farming households, with 67.5% of these households headed by males. The age of these farmers was equally shared at 40% each between those above 65 years and those that only went as far as fourth grade. No one went to tertiary at all. At least 75% of the investigated farmers were unemployed and 42% of this population was pensioners. In terms of income though, 64.98% of it was from external sources. The Masakhane Silime (Chicory) project was implemented to generate income and provide job opportunities for the locals but neither of these objectives had been met at the time the data for this study was collected due to various challenges like lack of funds and infrastructure to enhance productivity. Just like the chicory project, the livestock project had its own objectives, namely; to remove animals from the residential areas, provide the animals with a safe place, reduce road accidents and also to provide a livelihood source for local farmers. Due to overgrazing the pastures, lack of proper camps and other challenges, some effort still needs to be put to achieve these objectives. Even though the livestock project was formed with these objectives in mind, the farmers themselves reared livestock either for personal consumption, selling, ritual purposes, store of wealth or all these combined. Regarding technical skills, livestock farmers were found to rely mostly on indigenous knowledge sources to attain farming knowledge. Only animal healthcare knowledge was popular to more than half the respondents. This was said to be due to the focus group meetings held on the farm every other Wednesday to share information with local extension officers. In spite of these information sharing events, livestock farmers identified training on how to feed; market; handle; and treat their livestock as key intervention knowledge areas. Attendance to these focus group meetings was limited to livestock farmers only. Various socio-economic factors were also found to have some form of influence on the acquisition of livestock knowledge. Education was the most dominant factor, with a significant association with the farmers‟ feeding (p=0.033); animal healthcare (P=0.038); marketing (p=0.009); veld management (p=0.036); and cattle slaughtering (p=0.027) knowledge. Other variables most influential include the gender and age of the household head. The former was significant at 95% confidence level for farmers‟ feeding knowledge (p=0.021); animal healthcare (p=0.039); marketing (p=0.043); livestock housing and handling (p=0.023); veld management (p=0.018); and cattle slaughtering (p=0.043). The dominance of males in acquiring these skills could be explained by the fact that the majority of the livestock project members were males. The majority of the few female members became members by default after the passing on of their husbands but their participation in the project was done through other project members who looked after their animals on their behalf. The number of farming years also had some positive and significant influence on other knowledge areas such as feeding (p=0.021) and livestock housing and handling (p=0.013). The logic supporting this association is that farmers tend to accumulate new and more skills the longer they stay in the same enterprise. In addition, most of the interviewed farmers were farm labourers prior to relocating to Marselle hence they acquired the necessary knowledge long before the project started. Concerning the chicory project, its members also relied heavily on indigenous knowledge sources for farming knowledge. Soil preparation (24.1%); planting (20.7%); land care (24.1%); and mechanical weed control (48.3%) were the knowledge areas lacked by more than half the respondents. The farmers identified land preparation (75%); communication skills (25%); marketing (100%); financial management (62%); and harvesting (88%) as the key crucial intervention areas they needed prioritized. As a study meant to inform the capacity building phase of the Land Bank project, this study identified the existing skills gaps in the two projects implemented in Forest Hill. When implementing the Capacity Building (CB) phase, various socio-economic factors will have to be considered. For example, the proposed intervention should not discriminate against anyone on the grounds of gender or physical abilities. The skills introduced should also be simple enough to be accepted and acquired even by the illiterate, especially when one considers the high illiteracy levels amongst the respondents. Efforts should also be made to create partnerships with the right organizations or groups of people so that they provide the required expertise and resources for the benefit of the farmers as and when required.
- Full Text:
- Date Issued: 2013
- Authors: Tshuma, Mengezi Chancellor
- Date: 2013
- Subjects: Land reforms -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Agricultural Economics)
- Identifier: vital:11205 , http://hdl.handle.net/10353/d1013109 , Land reforms -- South Africa -- Eastern Cape , Agricultural development projects -- South Africa -- Eastern Cape , Rural development -- South Africa -- Eastern Cape , Farms, Small -- South Africa -- Eastern Cape
- Description: black owners by white colonialists. Even though whites made up less than 20% of the nation‟s population, they took more than 80% of the agriculturally productive land and drove the original owners to the unproductive reserves where they were cramped and could not practice agriculture at all. Various acts such as the Black Land Act of 1913, Development Trust Act of 1936 and the Native Laws Amendment Act of 1937 were introduced which further frustrated the displaced black population thereby plunging it deeper and deeper into poverty. The main objective behind the introduction of these acts was to restrain the black population from earning livelihoods through agriculture thus forcing them to offer their labour to white farmers for low wages just to earn some form of livelihood. Such unfair practices and distribution of land prompted the first democratically elected government of South Africa to embark on a drive to redistribute the nation‟s land equitably amongst its citizens to foster national reconciliation, stimulate economic growth and compensate those that were forced out or lost their land during the apartheid era. This initiative was called the Land Reform Programme (LRP) and was implemented with three prongs namely (i) land redistribution; (ii) restitution; and (iii) land tenure. Among the beneficiaries of the LRP were farmers from a community called Marselle in Kenton-on-sea. In addition to getting land for farming purposes, the Marselle farmers also obtained financial support from the government‟s Land Bank to help them kick-start their farming activities. However, in spite of such interventions, they have struggled to turn their activities into sustainable livelihood sources. One most likely cause for this is the lack of farming knowledge and skills needed to make them more efficient and productive. This study was thus geared towards evaluating the knowledge and skills gap in Marselle which, when addressed, could make the Marselle farmers more productive. Its focus was limited to the 32 livestock and 8 chicory farmers that are recognized members of their respective projects. Focus was limited only to these farmers since the next phase of this study will involve building their capacity based on the skills gaps identified through this study. The findings showed that the two projects benefited at least 130 individuals belonging to the farming households, with 67.5% of these households headed by males. The age of these farmers was equally shared at 40% each between those above 65 years and those that only went as far as fourth grade. No one went to tertiary at all. At least 75% of the investigated farmers were unemployed and 42% of this population was pensioners. In terms of income though, 64.98% of it was from external sources. The Masakhane Silime (Chicory) project was implemented to generate income and provide job opportunities for the locals but neither of these objectives had been met at the time the data for this study was collected due to various challenges like lack of funds and infrastructure to enhance productivity. Just like the chicory project, the livestock project had its own objectives, namely; to remove animals from the residential areas, provide the animals with a safe place, reduce road accidents and also to provide a livelihood source for local farmers. Due to overgrazing the pastures, lack of proper camps and other challenges, some effort still needs to be put to achieve these objectives. Even though the livestock project was formed with these objectives in mind, the farmers themselves reared livestock either for personal consumption, selling, ritual purposes, store of wealth or all these combined. Regarding technical skills, livestock farmers were found to rely mostly on indigenous knowledge sources to attain farming knowledge. Only animal healthcare knowledge was popular to more than half the respondents. This was said to be due to the focus group meetings held on the farm every other Wednesday to share information with local extension officers. In spite of these information sharing events, livestock farmers identified training on how to feed; market; handle; and treat their livestock as key intervention knowledge areas. Attendance to these focus group meetings was limited to livestock farmers only. Various socio-economic factors were also found to have some form of influence on the acquisition of livestock knowledge. Education was the most dominant factor, with a significant association with the farmers‟ feeding (p=0.033); animal healthcare (P=0.038); marketing (p=0.009); veld management (p=0.036); and cattle slaughtering (p=0.027) knowledge. Other variables most influential include the gender and age of the household head. The former was significant at 95% confidence level for farmers‟ feeding knowledge (p=0.021); animal healthcare (p=0.039); marketing (p=0.043); livestock housing and handling (p=0.023); veld management (p=0.018); and cattle slaughtering (p=0.043). The dominance of males in acquiring these skills could be explained by the fact that the majority of the livestock project members were males. The majority of the few female members became members by default after the passing on of their husbands but their participation in the project was done through other project members who looked after their animals on their behalf. The number of farming years also had some positive and significant influence on other knowledge areas such as feeding (p=0.021) and livestock housing and handling (p=0.013). The logic supporting this association is that farmers tend to accumulate new and more skills the longer they stay in the same enterprise. In addition, most of the interviewed farmers were farm labourers prior to relocating to Marselle hence they acquired the necessary knowledge long before the project started. Concerning the chicory project, its members also relied heavily on indigenous knowledge sources for farming knowledge. Soil preparation (24.1%); planting (20.7%); land care (24.1%); and mechanical weed control (48.3%) were the knowledge areas lacked by more than half the respondents. The farmers identified land preparation (75%); communication skills (25%); marketing (100%); financial management (62%); and harvesting (88%) as the key crucial intervention areas they needed prioritized. As a study meant to inform the capacity building phase of the Land Bank project, this study identified the existing skills gaps in the two projects implemented in Forest Hill. When implementing the Capacity Building (CB) phase, various socio-economic factors will have to be considered. For example, the proposed intervention should not discriminate against anyone on the grounds of gender or physical abilities. The skills introduced should also be simple enough to be accepted and acquired even by the illiterate, especially when one considers the high illiteracy levels amongst the respondents. Efforts should also be made to create partnerships with the right organizations or groups of people so that they provide the required expertise and resources for the benefit of the farmers as and when required.
- Full Text:
- Date Issued: 2013
Politics, polemics and practice: a history of narratives about, and responses to, AIDS in South Africa, 1980-1995
- Authors: Tsampiras, Carla
- Date: 2013
- Subjects: AIDS (Disease) -- Government policy -- South Africa AIDS (Disease) -- Political aspects -- South Africa -- History AIDS (Disease) -- South Africa -- Public opinion -- History AIDS (Disease) -- Social aspects -- South Africa -- History South Africa -- Politics and government -- 20th century African National Congress Health Policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2517 , http://hdl.handle.net/10962/d1001653
- Description: The ongoing urgency of addressing AIDS in South Africa has kept academics and activists focussed primarily on the immediate crises of AIDS ‘in the present’. This thesis, covering the period 1980 – 1995, examines narratives about, and responses to, AIDS ‘in the past’ and explores the interplay between these narratives and elites in medical and political communities trying to address AIDS during a period of political transition. The thesis begins by examining the hegemonic medico-scientific narratives about AIDS that featured in the South African Medical Journal, an important site of enquiry as AIDS was primarily conceived of as a ‘medical issue’. The SAMJ narratives, which often relied on constructed ‘AIDS avatars’, framed understandings of the syndrome and influenced responses to it by medical and political communities. The first community that the thesis explores is the African National Congress (ANC) in exile, which had to address AIDS in exile communities and prepare health strategies for ‘the new South Africa’. Secondly, the thesis analyses government responses to AIDS and argues that four phases of response can be identified. These phases were characterised by minimum concerns about obtaining information and providing health advice; efforts to gather infection data while exploiting political and public fear; attempts to extend health education and (belatedly) encourage broader engagement; and finally, consultative, democratic ideals. The thesis then examines the National Medical and Dental Association (NAMDA) a progressive medical organisation that worked with the ANC on influential health (and AIDS) strategies. NAMDA members ‘crossed over’ between various medical and political communities and both reinforced and challenged hegemonic AIDS narratives. Finally, the thesis moves from the abstract, via the practical, to the personal and concludes with a detailed account of the experiences of two sexuality activists at the intersections of these communities and narratives. By focussing on these medical and political communities, and analysing the relationships between these communities, the existing AIDS narratives, and individuals, the thesis also reveals the constructions of morality, ‘race’, gender, and sexuality that infused them. In doing this it shows how polemic and politics combined to influence practical responses to, and personal experiences of, AIDS.
- Full Text:
- Date Issued: 2013
- Authors: Tsampiras, Carla
- Date: 2013
- Subjects: AIDS (Disease) -- Government policy -- South Africa AIDS (Disease) -- Political aspects -- South Africa -- History AIDS (Disease) -- South Africa -- Public opinion -- History AIDS (Disease) -- Social aspects -- South Africa -- History South Africa -- Politics and government -- 20th century African National Congress Health Policy
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2517 , http://hdl.handle.net/10962/d1001653
- Description: The ongoing urgency of addressing AIDS in South Africa has kept academics and activists focussed primarily on the immediate crises of AIDS ‘in the present’. This thesis, covering the period 1980 – 1995, examines narratives about, and responses to, AIDS ‘in the past’ and explores the interplay between these narratives and elites in medical and political communities trying to address AIDS during a period of political transition. The thesis begins by examining the hegemonic medico-scientific narratives about AIDS that featured in the South African Medical Journal, an important site of enquiry as AIDS was primarily conceived of as a ‘medical issue’. The SAMJ narratives, which often relied on constructed ‘AIDS avatars’, framed understandings of the syndrome and influenced responses to it by medical and political communities. The first community that the thesis explores is the African National Congress (ANC) in exile, which had to address AIDS in exile communities and prepare health strategies for ‘the new South Africa’. Secondly, the thesis analyses government responses to AIDS and argues that four phases of response can be identified. These phases were characterised by minimum concerns about obtaining information and providing health advice; efforts to gather infection data while exploiting political and public fear; attempts to extend health education and (belatedly) encourage broader engagement; and finally, consultative, democratic ideals. The thesis then examines the National Medical and Dental Association (NAMDA) a progressive medical organisation that worked with the ANC on influential health (and AIDS) strategies. NAMDA members ‘crossed over’ between various medical and political communities and both reinforced and challenged hegemonic AIDS narratives. Finally, the thesis moves from the abstract, via the practical, to the personal and concludes with a detailed account of the experiences of two sexuality activists at the intersections of these communities and narratives. By focussing on these medical and political communities, and analysing the relationships between these communities, the existing AIDS narratives, and individuals, the thesis also reveals the constructions of morality, ‘race’, gender, and sexuality that infused them. In doing this it shows how polemic and politics combined to influence practical responses to, and personal experiences of, AIDS.
- Full Text:
- Date Issued: 2013
The application of the Rome Statute of the International Criminal Court to illegal natural resource exploitation in the Congo conflic
- Authors: Tsabora, James
- Date: 2013 , 2013-03-27
- Subjects: International criminal law -- Congo (Democratic Republic) Criminal procedure (International law) Natural resources -- Law and legislation -- Congo (Democratic Republic)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3665 , http://hdl.handle.net/10962/d1002612
- Description: This thesis explores the phenomenon of illegal natural resource exploitation in conflict zones and the application of international criminal law, particularly the Rome Statute of the International Criminal Court to combat the roblem. Contemporary African conflicts, such as the Democratic Republic of Congo conflict explored as a case study herein, have become increasingly distinguishable by the tight connection between war and various forms of illegal natural resource exploitation, particularly targeting valuable and precious mineral resources. With their incidence being highest in Africa, wars funded by illegally exploited natural resources have gradually become one of the greatest threats to regional peace and human security on the African continent. The Congo conflict clearly demonstrated the problematic nature and impact of illegal natural resource exploitation and the widespread human, economic and political costs associated with this phenomenon. This thesis is based on the initial assumption that the quest by conflict actors to profit from war through illegal natural resource exploitation activities is at the centre of the commission of serious human rights violations as well as the complexity and longevity of African conflicts. Developments in international criminal law, culminating in the adoption of the Rome Statute and the establishment of the International Criminal Court, have given impetus to the argument that any group of conflict actors should be subjected to the individual criminal responsibility regime of this legal framework. A further underlying assumption of this thesis is therefore that international criminal law can constrain the acts and conduct defined in this thesis as illegal natural resource exploitation activities since they constitute war crimes under the Rome Statute framework. However, despite illustrating the illegal resource exploitation activities of various state and non-state actors, this thesis is confined to an application of the Rome Statute based international criminal liability regime against members of armed rebel groups involved in such acts. In exploring these issues, this work examines international criminal law institutions and the relevance of international criminal justice in addressing particular phenomena prevalent during African armed conflicts. It further provides the stage to assess the potential of international criminal law in safeguarding natural resources for the benefit of African societies perennially exposed to the depredations of natural resource financed warfare. , Microsoft� Office Word 2007 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
- Authors: Tsabora, James
- Date: 2013 , 2013-03-27
- Subjects: International criminal law -- Congo (Democratic Republic) Criminal procedure (International law) Natural resources -- Law and legislation -- Congo (Democratic Republic)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3665 , http://hdl.handle.net/10962/d1002612
- Description: This thesis explores the phenomenon of illegal natural resource exploitation in conflict zones and the application of international criminal law, particularly the Rome Statute of the International Criminal Court to combat the roblem. Contemporary African conflicts, such as the Democratic Republic of Congo conflict explored as a case study herein, have become increasingly distinguishable by the tight connection between war and various forms of illegal natural resource exploitation, particularly targeting valuable and precious mineral resources. With their incidence being highest in Africa, wars funded by illegally exploited natural resources have gradually become one of the greatest threats to regional peace and human security on the African continent. The Congo conflict clearly demonstrated the problematic nature and impact of illegal natural resource exploitation and the widespread human, economic and political costs associated with this phenomenon. This thesis is based on the initial assumption that the quest by conflict actors to profit from war through illegal natural resource exploitation activities is at the centre of the commission of serious human rights violations as well as the complexity and longevity of African conflicts. Developments in international criminal law, culminating in the adoption of the Rome Statute and the establishment of the International Criminal Court, have given impetus to the argument that any group of conflict actors should be subjected to the individual criminal responsibility regime of this legal framework. A further underlying assumption of this thesis is therefore that international criminal law can constrain the acts and conduct defined in this thesis as illegal natural resource exploitation activities since they constitute war crimes under the Rome Statute framework. However, despite illustrating the illegal resource exploitation activities of various state and non-state actors, this thesis is confined to an application of the Rome Statute based international criminal liability regime against members of armed rebel groups involved in such acts. In exploring these issues, this work examines international criminal law institutions and the relevance of international criminal justice in addressing particular phenomena prevalent during African armed conflicts. It further provides the stage to assess the potential of international criminal law in safeguarding natural resources for the benefit of African societies perennially exposed to the depredations of natural resource financed warfare. , Microsoft� Office Word 2007 , Adobe Acrobat 9.53 Paper Capture Plug-in
- Full Text:
- Date Issued: 2013
Climate variability and climate change in water resources management of the Zambezi River basin
- Authors: Tirivarombo, Sithabile
- Date: 2013
- Subjects: Water resources development -- Zambezi River Watershed Climatic changes -- Zambezi River Watershed Water-supply -- Zambezi River Watershed Water-supply -- Political aspects -- Africa, Southern Water rights -- Africa, Southern Water security -- Africa, Southern Rain and rainfall -- Africa, Southern Rainfall probabilities -- Africa, Southern Food security -- Africa, Southern Drought forecasting -- Africa, Southern Watersheds -- Africa, Southern Water supply -- Measurement -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6024 , http://hdl.handle.net/10962/d1002955
- Description: Water is recognised as a key driver for social and economic development in the Zambezi basin. The basin is riparian to eight southern African countries and the transboundary nature of the basin’s water resources can be viewed as an agent of cooperation between the basin countries. It is possible, however, that the same water resource can lead to conflicts between water users. The southern African Water Vision for ‘equitable and sustainable utilisation of water for social, environmental justice and economic benefits for the present and future generations’ calls for an integrated and efficient management of water resources within the basin. Ensuring water and food security in the Zambezi basin is, however, faced with challenges due to high variability in climate and the available water resources. Water resources are under continuous threat from pollution, increased population growth, development and urbanisation as well as global climate change. These factors increase the demand for freshwater resources and have resulted in water being one of the major driving forces for development. The basin is also vulnerable due to lack of adequate financial resources and appropriate water resources infrastructure to enable viable, equitable and sustainable distribution of the water resources. This is in addition to the fact that the basin’s economic mainstay and social well-being are largely dependent on rainfed agriculture. There is also competition among the different water users and this has the potential to generate conflicts, which further hinder the development of water resources in the basin. This thesis has focused on the Zambezi River basin emphasising climate variability and climate change. It is now considered common knowledge that the global climate is changing and that many of the impacts will be felt through water resources. If these predictions are correct then the Zambezi basin is most likely to suffer under such impacts since its economic mainstay is largely determined by the availability of rainfall. It is the belief of this study that in order to ascertain the impacts of climate change, there should be a basis against which this change is evaluated. If we do not know the historical patterns of variability it may be difficult to predict changes in the future climate and in the hydrological resources and it will certainly be difficult to develop appropriate management strategies. Reliable quantitative estimates of water availability are a prerequisite for successful water resource plans. However, such initiatives have been hindered by paucity in data especially in a basin where gauging networks are inadequate and some of them have deteriorated. This is further compounded by shortages in resources, both human and financial, to ensure adequate monitoring. To address the data problems, this study largely relied on global data sets and the CRU TS2.1 rainfall grids were used for a large part of this study. The study starts by assessing the historical variability of rainfall and streamflow in the Zambezi basin and the results are used to inform the prediction of change in the future. Various methods of assessing historical trends were employed and regional drought indices were generated and evaluated against the historical rainfall trends. The study clearly demonstrates that the basin has a high degree of temporal and spatial variability in rainfall and streamflow at inter-annual and multi-decadal scales. The Standardised Precipitation Index, a rainfall based drought index, is used to assess historical drought events in the basin and it is shown that most of the droughts that have occurred were influenced by climatic and hydrological variability. It is concluded, through the evaluation of agricultural maize yields, that the basin’s food security is mostly constrained by the availability of rainfall. Comparing the viability of using a rainfall based index to a soil moisture based index as an agricultural drought indicator, this study concluded that a soil moisture based index is a better indicator since all of the water balance components are considered in the generation of the index. This index presents the actual amount of water available for the plant unlike purely rainfall based indices, that do not account for other components of the water budget that cause water losses. A number of challenges were, however, faced in assessing the variability and historical drought conditions, mainly due to the fact that most parts of the Zambezi basin are ungauged and available data are sparse, short and not continuous (with missing gaps). Hydrological modelling is frequently used to bridge the data gap and to facilitate the quantification of a basin’s hydrology for both gauged and ungauged catchments. The trend has been to use various methods of regionalisation to transfer information from gauged basins, or from basins with adequate physical basin data, to ungauged basins. All this is done to ensure that water resources are accounted for and that the future can be well planned. A number of approaches leading to the evaluation of the basin’s hydrological response to future climate change scenarios are taken. The Pitman rainfall-runoff model has enjoyed wide use as a water resources estimation tool in southern Africa. The model has been calibrated for the Zambezi basin but it should be acknowledged that any hydrological modelling process is characterised by many uncertainties arising from limitations in input data and inherent model structural uncertainty. The calibration process is thus carried out in a manner that embraces some of the uncertainties. Initial ranges of parameter values (maximum and minimum) that incorporate the possible parameter uncertainties are assigned in relation to physical basin properties. These parameter sets are used as input to the uncertainty version of the model to generate behavioural parameter space which is then further modified through manual calibration. The use of parameter ranges initially guided by the basin physical properties generates streamflows that adequately represent the historically observed amounts. This study concludes that the uncertainty framework and the Pitman model perform quite well in the Zambezi basin. Based on assumptions of an intensifying hydrological cycle, climate changes are frequently expected to result in negative impacts on water resources. However, it is important that basin scale assessments are undertaken so that appropriate future management strategies can be developed. To assess the likely changes in the Zambezi basin, the calibrated Pitman model was forced with downscaled and bias corrected GCM data. Three GCMs were used for this study, namely; ECHAM, GFDL and IPSL. The general observation made in this study is that the near future (2046-2065) conditions of the Zambezi basin are expected to remain within the ranges of historically observed variability. The differences between the predictions for the three GCMs are an indication of the uncertainties in the future and it has not been possible to make any firm conclusions about directions of change. It is therefore recommended that future water resources management strategies account for historical patterns of variability, but also for increased uncertainty. Any management strategies that are able to satisfactorily deal with the large variability that is evident from the historical data should be robust enough to account for the near future patterns of water availability predicted by this study. However, the uncertainties in these predictions suggest that improved monitoring systems are required to provide additional data against which future model outputs can be assessed.
- Full Text:
- Date Issued: 2013
- Authors: Tirivarombo, Sithabile
- Date: 2013
- Subjects: Water resources development -- Zambezi River Watershed Climatic changes -- Zambezi River Watershed Water-supply -- Zambezi River Watershed Water-supply -- Political aspects -- Africa, Southern Water rights -- Africa, Southern Water security -- Africa, Southern Rain and rainfall -- Africa, Southern Rainfall probabilities -- Africa, Southern Food security -- Africa, Southern Drought forecasting -- Africa, Southern Watersheds -- Africa, Southern Water supply -- Measurement -- Africa, Southern
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:6024 , http://hdl.handle.net/10962/d1002955
- Description: Water is recognised as a key driver for social and economic development in the Zambezi basin. The basin is riparian to eight southern African countries and the transboundary nature of the basin’s water resources can be viewed as an agent of cooperation between the basin countries. It is possible, however, that the same water resource can lead to conflicts between water users. The southern African Water Vision for ‘equitable and sustainable utilisation of water for social, environmental justice and economic benefits for the present and future generations’ calls for an integrated and efficient management of water resources within the basin. Ensuring water and food security in the Zambezi basin is, however, faced with challenges due to high variability in climate and the available water resources. Water resources are under continuous threat from pollution, increased population growth, development and urbanisation as well as global climate change. These factors increase the demand for freshwater resources and have resulted in water being one of the major driving forces for development. The basin is also vulnerable due to lack of adequate financial resources and appropriate water resources infrastructure to enable viable, equitable and sustainable distribution of the water resources. This is in addition to the fact that the basin’s economic mainstay and social well-being are largely dependent on rainfed agriculture. There is also competition among the different water users and this has the potential to generate conflicts, which further hinder the development of water resources in the basin. This thesis has focused on the Zambezi River basin emphasising climate variability and climate change. It is now considered common knowledge that the global climate is changing and that many of the impacts will be felt through water resources. If these predictions are correct then the Zambezi basin is most likely to suffer under such impacts since its economic mainstay is largely determined by the availability of rainfall. It is the belief of this study that in order to ascertain the impacts of climate change, there should be a basis against which this change is evaluated. If we do not know the historical patterns of variability it may be difficult to predict changes in the future climate and in the hydrological resources and it will certainly be difficult to develop appropriate management strategies. Reliable quantitative estimates of water availability are a prerequisite for successful water resource plans. However, such initiatives have been hindered by paucity in data especially in a basin where gauging networks are inadequate and some of them have deteriorated. This is further compounded by shortages in resources, both human and financial, to ensure adequate monitoring. To address the data problems, this study largely relied on global data sets and the CRU TS2.1 rainfall grids were used for a large part of this study. The study starts by assessing the historical variability of rainfall and streamflow in the Zambezi basin and the results are used to inform the prediction of change in the future. Various methods of assessing historical trends were employed and regional drought indices were generated and evaluated against the historical rainfall trends. The study clearly demonstrates that the basin has a high degree of temporal and spatial variability in rainfall and streamflow at inter-annual and multi-decadal scales. The Standardised Precipitation Index, a rainfall based drought index, is used to assess historical drought events in the basin and it is shown that most of the droughts that have occurred were influenced by climatic and hydrological variability. It is concluded, through the evaluation of agricultural maize yields, that the basin’s food security is mostly constrained by the availability of rainfall. Comparing the viability of using a rainfall based index to a soil moisture based index as an agricultural drought indicator, this study concluded that a soil moisture based index is a better indicator since all of the water balance components are considered in the generation of the index. This index presents the actual amount of water available for the plant unlike purely rainfall based indices, that do not account for other components of the water budget that cause water losses. A number of challenges were, however, faced in assessing the variability and historical drought conditions, mainly due to the fact that most parts of the Zambezi basin are ungauged and available data are sparse, short and not continuous (with missing gaps). Hydrological modelling is frequently used to bridge the data gap and to facilitate the quantification of a basin’s hydrology for both gauged and ungauged catchments. The trend has been to use various methods of regionalisation to transfer information from gauged basins, or from basins with adequate physical basin data, to ungauged basins. All this is done to ensure that water resources are accounted for and that the future can be well planned. A number of approaches leading to the evaluation of the basin’s hydrological response to future climate change scenarios are taken. The Pitman rainfall-runoff model has enjoyed wide use as a water resources estimation tool in southern Africa. The model has been calibrated for the Zambezi basin but it should be acknowledged that any hydrological modelling process is characterised by many uncertainties arising from limitations in input data and inherent model structural uncertainty. The calibration process is thus carried out in a manner that embraces some of the uncertainties. Initial ranges of parameter values (maximum and minimum) that incorporate the possible parameter uncertainties are assigned in relation to physical basin properties. These parameter sets are used as input to the uncertainty version of the model to generate behavioural parameter space which is then further modified through manual calibration. The use of parameter ranges initially guided by the basin physical properties generates streamflows that adequately represent the historically observed amounts. This study concludes that the uncertainty framework and the Pitman model perform quite well in the Zambezi basin. Based on assumptions of an intensifying hydrological cycle, climate changes are frequently expected to result in negative impacts on water resources. However, it is important that basin scale assessments are undertaken so that appropriate future management strategies can be developed. To assess the likely changes in the Zambezi basin, the calibrated Pitman model was forced with downscaled and bias corrected GCM data. Three GCMs were used for this study, namely; ECHAM, GFDL and IPSL. The general observation made in this study is that the near future (2046-2065) conditions of the Zambezi basin are expected to remain within the ranges of historically observed variability. The differences between the predictions for the three GCMs are an indication of the uncertainties in the future and it has not been possible to make any firm conclusions about directions of change. It is therefore recommended that future water resources management strategies account for historical patterns of variability, but also for increased uncertainty. Any management strategies that are able to satisfactorily deal with the large variability that is evident from the historical data should be robust enough to account for the near future patterns of water availability predicted by this study. However, the uncertainties in these predictions suggest that improved monitoring systems are required to provide additional data against which future model outputs can be assessed.
- Full Text:
- Date Issued: 2013
The impact of diversity and organisational culture on effective strategy implementation in a higher education institution
- Authors: Strydom, Kariena
- Date: 2013
- Subjects: Diversity in the workplace -- South Africa Corporate culture -- South Africa , Organizational behavior -- South Africa Business anthropology Education, Higher -- South Africa
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: http://hdl.handle.net/10948/21691 , vital:29734
- Description: Diversity should be included in an organisational culture and be aligned with the corporate strategy. South African institutions face diversity and multiculturalism challenges which affect their operation and strategies. Managers in South Africa regard organisational culture as a very useful tool to manage their diverse workforce. Against this background, the primary objective of this study was to investigate and analyse how workforce diversity and organisational culture impact on strategy implementation at a higher education institution, namely Walter Sisulu University (WSU). The study identified dimensions of diversity and organisational culture and strategy implementation from theoretical models supporting the study. A hypothetical model portraying these factors was constructed, displaying each factor and their relationship with strategy implementation. Furthermore, the relationship between strategy implementation and strategic outcomes was indicated. Given the nature of the problem statement and the research objectives presented in this study, the positivistic research paradigm was adopted. Self-administered questionnaires were distributed to executive and senior management, senior academic and senior support staff at WSU. In total, 266 usable questionnaires were returned. The data obtained from these questionnaires were subjected to both descriptive and inferential statistical analyses. Structural equation modeling (SEM) was used as the key statistical analysis tool. As the hypothetical model did not load onto SEM in total, it was re-specified into four sub-models. Each sub-model was subjected to SEM to test the hypothetical model and to indicate the significance of the relationships hypothesised between the various independent, mediating and dependent variables. Eight statistically significant relationships were identified in the study. The factors identified as having a statistically significant relationship with organisational culture included the following: degree of flexibility, degree of teamwork, task directiveness, degree of formalisation, leadership styles and decision making. In addition, a statistically significant relationship was found between organisational culture and strategy implementation. Furthermore the findings indicated a statistically significant relationship between strategy implementation and strategic outcomes in a higher education institution. There was no statistically significant relationship found between diversity and strategy implementation. This finding is contrary to empirical evidence by various other researchers. The study makes a contribution to multicultural higher education institutions by highlighting the crucial role of organisational culture in effective strategy implementation. It was clear from the results of the study that the nurturing of human capital is critical if higher education institutions wish to successfully aligning culture with strategy implementation. This study provided constructive and very practical guidelines to higher education institutions to ensure effective alignment of culture with strategy implementation and so enhance local and global competitiveness and long term sustainability. University councils throughout South Africa can apply the findings of this study in their respective institutions to support effective strategy execution.
- Full Text:
- Date Issued: 2013
- Authors: Strydom, Kariena
- Date: 2013
- Subjects: Diversity in the workplace -- South Africa Corporate culture -- South Africa , Organizational behavior -- South Africa Business anthropology Education, Higher -- South Africa
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: http://hdl.handle.net/10948/21691 , vital:29734
- Description: Diversity should be included in an organisational culture and be aligned with the corporate strategy. South African institutions face diversity and multiculturalism challenges which affect their operation and strategies. Managers in South Africa regard organisational culture as a very useful tool to manage their diverse workforce. Against this background, the primary objective of this study was to investigate and analyse how workforce diversity and organisational culture impact on strategy implementation at a higher education institution, namely Walter Sisulu University (WSU). The study identified dimensions of diversity and organisational culture and strategy implementation from theoretical models supporting the study. A hypothetical model portraying these factors was constructed, displaying each factor and their relationship with strategy implementation. Furthermore, the relationship between strategy implementation and strategic outcomes was indicated. Given the nature of the problem statement and the research objectives presented in this study, the positivistic research paradigm was adopted. Self-administered questionnaires were distributed to executive and senior management, senior academic and senior support staff at WSU. In total, 266 usable questionnaires were returned. The data obtained from these questionnaires were subjected to both descriptive and inferential statistical analyses. Structural equation modeling (SEM) was used as the key statistical analysis tool. As the hypothetical model did not load onto SEM in total, it was re-specified into four sub-models. Each sub-model was subjected to SEM to test the hypothetical model and to indicate the significance of the relationships hypothesised between the various independent, mediating and dependent variables. Eight statistically significant relationships were identified in the study. The factors identified as having a statistically significant relationship with organisational culture included the following: degree of flexibility, degree of teamwork, task directiveness, degree of formalisation, leadership styles and decision making. In addition, a statistically significant relationship was found between organisational culture and strategy implementation. Furthermore the findings indicated a statistically significant relationship between strategy implementation and strategic outcomes in a higher education institution. There was no statistically significant relationship found between diversity and strategy implementation. This finding is contrary to empirical evidence by various other researchers. The study makes a contribution to multicultural higher education institutions by highlighting the crucial role of organisational culture in effective strategy implementation. It was clear from the results of the study that the nurturing of human capital is critical if higher education institutions wish to successfully aligning culture with strategy implementation. This study provided constructive and very practical guidelines to higher education institutions to ensure effective alignment of culture with strategy implementation and so enhance local and global competitiveness and long term sustainability. University councils throughout South Africa can apply the findings of this study in their respective institutions to support effective strategy execution.
- Full Text:
- Date Issued: 2013