Analysis of the reliability for the 132/66/22 KV distribution network within ESKOM’s Eastern Cape operating unit
- Authors: Pantshwa, Athini
- Date: 2017
- Subjects: Electric power distribution Electricity -- Supply -- Engineering , Smart power grids
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/19750 , vital:28953
- Description: A stable and reliable electrical power supply system is an inevitable pre-requisite for the technological and economic growth of any nation. Due to this, utilities must strive and ensure that the customer’s reliability requirements are met and that the regulators requirements are satisfied at the lowest possible cost. It is known fact around the world that 90% of the customer service interruptions are caused due to failure in distribution system. Therefore, it is worth considering reliability assessments as it provides an opportunity to incorporate the cost or losses incurred by the utilities customer as a result of power failure. This must be considered in the planning and operating practices. The system modelling and simulation study is carried out on one of the district’s distribution system which consists of 132 kV, 66 kV and 22 kV network in Aliwal North Sector ECOU. The reliability assessment is done on the 22, 66 and 132 kV system to assess the performance of the present system and also predictive reliability analysis for the future system considering load growth and system expansion. The alternative which gives low SAIDI, SAIFI and minimum breakeven costs is being assessed and considered. The reliability of 132 kV system could be further improved by constructing a new 132 kV line from a different source of supply and connecting with line coming from another district (reserve) at reasonable break even cost. The decision base could be further improved by having Aliwal North Sector context interruption cost. However, the historical data which may be used in Aliwal North Sector to acquire interruption costs from the customers are being proposed. The focus should be on improving the power quality on constrained networks first, then the reliability. Therefore for the Aliwal North power system network it is imperative that Eskom invest on the reliability of this network. This dissertation also analysed load reflected economic benefit versus performance expectations that should be optimized through achieving a balance between network performance (SAIDI) improvement, and total life cycle cost (to Eskom as well as the economy). Reliability analysis conducted in this dissertation used Aliwal North power system network as a case study; the results proved that the system is vulnerable to faults, planned and unplanned outages. Reliability evaluation studies were conducted on the system using DigSilent software in conjunction with FME. These two models gave accurate results with acceptable variance in most indices except for the ENS where the variance was quite significant. It can be concluded that DigSilent results are the most accurate results in all three reliability evaluation scenarios for the Aliwal North Power System, best interpretation being that of DigSilent.
- Full Text:
- Date Issued: 2017
- Authors: Pantshwa, Athini
- Date: 2017
- Subjects: Electric power distribution Electricity -- Supply -- Engineering , Smart power grids
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/19750 , vital:28953
- Description: A stable and reliable electrical power supply system is an inevitable pre-requisite for the technological and economic growth of any nation. Due to this, utilities must strive and ensure that the customer’s reliability requirements are met and that the regulators requirements are satisfied at the lowest possible cost. It is known fact around the world that 90% of the customer service interruptions are caused due to failure in distribution system. Therefore, it is worth considering reliability assessments as it provides an opportunity to incorporate the cost or losses incurred by the utilities customer as a result of power failure. This must be considered in the planning and operating practices. The system modelling and simulation study is carried out on one of the district’s distribution system which consists of 132 kV, 66 kV and 22 kV network in Aliwal North Sector ECOU. The reliability assessment is done on the 22, 66 and 132 kV system to assess the performance of the present system and also predictive reliability analysis for the future system considering load growth and system expansion. The alternative which gives low SAIDI, SAIFI and minimum breakeven costs is being assessed and considered. The reliability of 132 kV system could be further improved by constructing a new 132 kV line from a different source of supply and connecting with line coming from another district (reserve) at reasonable break even cost. The decision base could be further improved by having Aliwal North Sector context interruption cost. However, the historical data which may be used in Aliwal North Sector to acquire interruption costs from the customers are being proposed. The focus should be on improving the power quality on constrained networks first, then the reliability. Therefore for the Aliwal North power system network it is imperative that Eskom invest on the reliability of this network. This dissertation also analysed load reflected economic benefit versus performance expectations that should be optimized through achieving a balance between network performance (SAIDI) improvement, and total life cycle cost (to Eskom as well as the economy). Reliability analysis conducted in this dissertation used Aliwal North power system network as a case study; the results proved that the system is vulnerable to faults, planned and unplanned outages. Reliability evaluation studies were conducted on the system using DigSilent software in conjunction with FME. These two models gave accurate results with acceptable variance in most indices except for the ENS where the variance was quite significant. It can be concluded that DigSilent results are the most accurate results in all three reliability evaluation scenarios for the Aliwal North Power System, best interpretation being that of DigSilent.
- Full Text:
- Date Issued: 2017
Ant colony optimisation-based algorithms for optical burst switching networks
- Gravett, Andrew Scott, Gibbon, Timothy B
- Authors: Gravett, Andrew Scott , Gibbon, Timothy B
- Date: 2017
- Subjects: Distributed algorithms , Ants -- Behavior -- Mathematical models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/18939 , vital:28757
- Description: This research developed two novel distributed algorithms inspired by Ant Colony Optimisation (ACO) for a solution to the problem of dynamic Routing and Wavelength Assignment (RWA) with wavelength continuity constraint in Optical Burst Switching (OBS) networks utilising both the traditional International Telecommunication Union (ITU) Fixed Grid Wavelength Division Multiplexing (WDM) and Flexible Spectrum scenarios. The growing demand for more bandwidth in optical networks require more efficient utilisation of available optical resources. OBS is a promising optical switching technique for the improved utilisation of optical network resources over the current optical circuit switching technique. The development of newer technologies has introduced higher rate transmissions and various modulation formats, however, introducing these technologies into the traditional ITU Fixed Grid does not efficiently utilise the available bandwidth. Flexible Spectrum is a promising approach offering a solution to the problem of improving bandwidth utilisation, which comes with a potential cost. Transmissions have the potential for impairment with respect to the increased traffic and lack of large channel spacing. Proposed routing algorithms should be aware of the linear and non-linear Physical Layer Impairments (PLIs) in order to operate closer to optimum performance. The OBS resource reservation protocol does not cater for the loss of transmissions, Burst Control Packets (BCPs) included, due to physical layer impairments. The protocol was adapted for use in Flexible Spectrum. Investigation of the use of a route and wavelength combination, from source to destination node pair, for the RWA process was proposed for ACO-based approaches to enforce the establishment and use of complete paths for greedy exploitation in Flexible Spectrum was conducted. The routing tuple for the RWA process is the tight coupling of a route and wavelength in combination intended to promote the greedy exploitation of successful paths for transmission requests. The application of the routing tuples differs from traditional ACO-based approaches and prompted the investigation of new pheromone calculation equations. The two novel proposed approaches were tested and experiments conducted comparing with and against existing algorithms (a simple greedy and an ACO-based algorithm) in a traditional ITU Fixed Grid and Flexible Spectrum scenario on three different network topologies. The proposed Flexible Spectrum Ant Colony (FSAC) approach had a markably improved performance over the existing algorithms in the ITU Fixed Grid WDM and Flexible Spectrum scenarios, while Upper Confidence Bound Routing and Wavelength Assignment (UCBRWA) algorithm was able to perform well in the traditional ITU Fixed Grid WDM scenario, but underperformed in the Flexible Spectrum scenario. The results show that the distributed ACO-based FSAC algorithm significantly improved the burst transmission success probability, providing a good solution in the Flexible Spectrum network environment undergoing transmission impairments.
- Full Text:
- Date Issued: 2017
- Authors: Gravett, Andrew Scott , Gibbon, Timothy B
- Date: 2017
- Subjects: Distributed algorithms , Ants -- Behavior -- Mathematical models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/18939 , vital:28757
- Description: This research developed two novel distributed algorithms inspired by Ant Colony Optimisation (ACO) for a solution to the problem of dynamic Routing and Wavelength Assignment (RWA) with wavelength continuity constraint in Optical Burst Switching (OBS) networks utilising both the traditional International Telecommunication Union (ITU) Fixed Grid Wavelength Division Multiplexing (WDM) and Flexible Spectrum scenarios. The growing demand for more bandwidth in optical networks require more efficient utilisation of available optical resources. OBS is a promising optical switching technique for the improved utilisation of optical network resources over the current optical circuit switching technique. The development of newer technologies has introduced higher rate transmissions and various modulation formats, however, introducing these technologies into the traditional ITU Fixed Grid does not efficiently utilise the available bandwidth. Flexible Spectrum is a promising approach offering a solution to the problem of improving bandwidth utilisation, which comes with a potential cost. Transmissions have the potential for impairment with respect to the increased traffic and lack of large channel spacing. Proposed routing algorithms should be aware of the linear and non-linear Physical Layer Impairments (PLIs) in order to operate closer to optimum performance. The OBS resource reservation protocol does not cater for the loss of transmissions, Burst Control Packets (BCPs) included, due to physical layer impairments. The protocol was adapted for use in Flexible Spectrum. Investigation of the use of a route and wavelength combination, from source to destination node pair, for the RWA process was proposed for ACO-based approaches to enforce the establishment and use of complete paths for greedy exploitation in Flexible Spectrum was conducted. The routing tuple for the RWA process is the tight coupling of a route and wavelength in combination intended to promote the greedy exploitation of successful paths for transmission requests. The application of the routing tuples differs from traditional ACO-based approaches and prompted the investigation of new pheromone calculation equations. The two novel proposed approaches were tested and experiments conducted comparing with and against existing algorithms (a simple greedy and an ACO-based algorithm) in a traditional ITU Fixed Grid and Flexible Spectrum scenario on three different network topologies. The proposed Flexible Spectrum Ant Colony (FSAC) approach had a markably improved performance over the existing algorithms in the ITU Fixed Grid WDM and Flexible Spectrum scenarios, while Upper Confidence Bound Routing and Wavelength Assignment (UCBRWA) algorithm was able to perform well in the traditional ITU Fixed Grid WDM scenario, but underperformed in the Flexible Spectrum scenario. The results show that the distributed ACO-based FSAC algorithm significantly improved the burst transmission success probability, providing a good solution in the Flexible Spectrum network environment undergoing transmission impairments.
- Full Text:
- Date Issued: 2017
Anti-fetishism: parodying the depiction of the female body as fetish
- Authors: Pirie, René Alexis
- Date: 2017
- Subjects: Body image -- Social aspects Fashion -- Social aspects
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/20377 , vital:29272
- Description: sexual objectification of women is widespread in contemporary lifestyle and fashion magazines. Models used for advertising purposes often set a standard of beauty and youth that is unrealistic and limiting. This standard has damaging effects on women’s sense of self and their societal behaviour. Such images not only sexualise as well as fetishise women’s bodies, but also encourage self-surveillance. This research study examines Cindy Sherman, Sarah Lucas, Louise Bourgeois and Ángela Burón’s artistic responses to fetishized images of women, in order to assess what artistic strategies could be used to oppose such images in magazine advertisements. It aims to identify what anti-fetishism involves in theory and practice and to use this information to formulate an anti-fetish strategy which informs a series of anti-fetish artworks. The purpose of this series of works is to oppose the fetishization of women, particularly in magazine advertisements of high-end consumer products. The study contributes to the discourse of anti-fetishism and addresses a knowledge gap since research on anti-fetishism has much room for development. It is a Qualitative research study which adhered to a Practice-based research method. The key findings of this study are that anti-fetishism and female fetishism are approaches that differ from one another yet also overlap. Furthermore, Anti-fetishism involves the use of parodic mockery, while female fetishism is concerned mostly with undecidability as a strategy. From the examination of the artists, the anti-fetishistic strategy of parody, largely influenced the practical component of this research study. Parody offers a clear opposition to the still widespread fetishization of women in magazines both in South Africa and other Westernized countries across the world.
- Full Text:
- Date Issued: 2017
- Authors: Pirie, René Alexis
- Date: 2017
- Subjects: Body image -- Social aspects Fashion -- Social aspects
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/20377 , vital:29272
- Description: sexual objectification of women is widespread in contemporary lifestyle and fashion magazines. Models used for advertising purposes often set a standard of beauty and youth that is unrealistic and limiting. This standard has damaging effects on women’s sense of self and their societal behaviour. Such images not only sexualise as well as fetishise women’s bodies, but also encourage self-surveillance. This research study examines Cindy Sherman, Sarah Lucas, Louise Bourgeois and Ángela Burón’s artistic responses to fetishized images of women, in order to assess what artistic strategies could be used to oppose such images in magazine advertisements. It aims to identify what anti-fetishism involves in theory and practice and to use this information to formulate an anti-fetish strategy which informs a series of anti-fetish artworks. The purpose of this series of works is to oppose the fetishization of women, particularly in magazine advertisements of high-end consumer products. The study contributes to the discourse of anti-fetishism and addresses a knowledge gap since research on anti-fetishism has much room for development. It is a Qualitative research study which adhered to a Practice-based research method. The key findings of this study are that anti-fetishism and female fetishism are approaches that differ from one another yet also overlap. Furthermore, Anti-fetishism involves the use of parodic mockery, while female fetishism is concerned mostly with undecidability as a strategy. From the examination of the artists, the anti-fetishistic strategy of parody, largely influenced the practical component of this research study. Parody offers a clear opposition to the still widespread fetishization of women in magazines both in South Africa and other Westernized countries across the world.
- Full Text:
- Date Issued: 2017
Antibacterial activities of both combined and individual medicinal plants extracts traditionally used to treat pneumonia
- Authors: Mhango, Immaculate
- Date: 2017
- Subjects: Antibacterial agents , Pneumonia -- Treatment
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/19762 , vital:28959
- Description: Pneumonia is one of the five major leading causes of death in children under-fives years and the elderly worldwide. Antibiotics used for its treatment are less potent due to bacteria development of bacteria resistant to antibiotics. This has led to a surge in search of novel drugs. There are already some drugs in clinical use that have natural products and derivatives such as quinine, morphine, vincristine, and taxol among others. The healing value of medicinal plants has been well accepted since Stone Age across the globe. This plant therapy has been prescribed and prepared independently or in combination. The following plants: Terminalia sericea, Warburgia salutaris, Dodonea angustofolia, Eucalyptus camaldulensis, Ballota africana, Kigelia africana and Acorus gramineus. These plants are most commonly used for treatment of pneumonia and other ailment, were studied to validate their antimicrobial activity based on scientific determination. The primary aim of this study was to evaluate the efficacy of these plants against bacteria pneumonia pathogens. Seven medicinal plants, independently and in combinations were relatively analysed for their antimicrobial activity against Staphylococcus aureus, Streptococcus pyogenes, and Klebsiella pneumoniae. Ground plant material of roots, bark and leafs were prepared with acetone, ethanol and distilled water. Dimethyl sulfoxide (10 &100%) was used as a reconstitution solvent and ciprofloxacin (10 %) as a positive control. The antimicrobial efficacy was determined using agar well diffusion and microtiter plate methods. Interaction between plants was evaluated by calculating fraction inhibitory concentration index (ΣFIC). Noteworthy activity for individual studies with all test organisms was observed with T. sericea. However, highest ZOI (30 mm) was observed for B. africana ethanol extract for S. pyogenes. Weak microbial activity was noted in W. salutaris and D. angustofolia extracts with all test organisms. Good antimicrobial activity was observed in combination studies with all organisms. The potency of different plant combinations varied with highest ZOI observed with B. africana and W. salutaris ranging from 33-35 mm, conversely ZOI of 35 mm was also noted for S. aureus in B. africana and E. camaldulensis ethanol extract. Noteworthy antimicrobial activity was observed in T. sericea and D. angustofolia against all test pathogens. weak antimicrobial activity with highest MICs was observed in combinations where W. salutaris was involved. After calculating ΣFICs, strongest synergistic effect was displayed for W. salutaris and D. angustofolia against all test organisms (lowest ΣFICs 0.0491). Most plant extract combinations, displayed either synergistic, additive or indifferent effect, with few demonstrating antagonistic interactions. Significant antagonism effect was noted for S. pyogenes with T. sericea ethanol extract ΣFIC value of 15.51. Based on results of this study use of plants in combination increase antimicrobial efficacy. The antimicrobial activities; synergistic and additive effects observed adds credibility in the use of plant combination for therapeutic value in treatment of pneumonia. Future studies are recommended to identify and isolate specific active compounds involved in plant combination interactions. The importance of combination studies for possible development of new antimicrobials that can succumb bacterial resistance need to be highlighted.
- Full Text:
- Date Issued: 2017
- Authors: Mhango, Immaculate
- Date: 2017
- Subjects: Antibacterial agents , Pneumonia -- Treatment
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/19762 , vital:28959
- Description: Pneumonia is one of the five major leading causes of death in children under-fives years and the elderly worldwide. Antibiotics used for its treatment are less potent due to bacteria development of bacteria resistant to antibiotics. This has led to a surge in search of novel drugs. There are already some drugs in clinical use that have natural products and derivatives such as quinine, morphine, vincristine, and taxol among others. The healing value of medicinal plants has been well accepted since Stone Age across the globe. This plant therapy has been prescribed and prepared independently or in combination. The following plants: Terminalia sericea, Warburgia salutaris, Dodonea angustofolia, Eucalyptus camaldulensis, Ballota africana, Kigelia africana and Acorus gramineus. These plants are most commonly used for treatment of pneumonia and other ailment, were studied to validate their antimicrobial activity based on scientific determination. The primary aim of this study was to evaluate the efficacy of these plants against bacteria pneumonia pathogens. Seven medicinal plants, independently and in combinations were relatively analysed for their antimicrobial activity against Staphylococcus aureus, Streptococcus pyogenes, and Klebsiella pneumoniae. Ground plant material of roots, bark and leafs were prepared with acetone, ethanol and distilled water. Dimethyl sulfoxide (10 &100%) was used as a reconstitution solvent and ciprofloxacin (10 %) as a positive control. The antimicrobial efficacy was determined using agar well diffusion and microtiter plate methods. Interaction between plants was evaluated by calculating fraction inhibitory concentration index (ΣFIC). Noteworthy activity for individual studies with all test organisms was observed with T. sericea. However, highest ZOI (30 mm) was observed for B. africana ethanol extract for S. pyogenes. Weak microbial activity was noted in W. salutaris and D. angustofolia extracts with all test organisms. Good antimicrobial activity was observed in combination studies with all organisms. The potency of different plant combinations varied with highest ZOI observed with B. africana and W. salutaris ranging from 33-35 mm, conversely ZOI of 35 mm was also noted for S. aureus in B. africana and E. camaldulensis ethanol extract. Noteworthy antimicrobial activity was observed in T. sericea and D. angustofolia against all test pathogens. weak antimicrobial activity with highest MICs was observed in combinations where W. salutaris was involved. After calculating ΣFICs, strongest synergistic effect was displayed for W. salutaris and D. angustofolia against all test organisms (lowest ΣFICs 0.0491). Most plant extract combinations, displayed either synergistic, additive or indifferent effect, with few demonstrating antagonistic interactions. Significant antagonism effect was noted for S. pyogenes with T. sericea ethanol extract ΣFIC value of 15.51. Based on results of this study use of plants in combination increase antimicrobial efficacy. The antimicrobial activities; synergistic and additive effects observed adds credibility in the use of plant combination for therapeutic value in treatment of pneumonia. Future studies are recommended to identify and isolate specific active compounds involved in plant combination interactions. The importance of combination studies for possible development of new antimicrobials that can succumb bacterial resistance need to be highlighted.
- Full Text:
- Date Issued: 2017
Antimalarial secondary metabolites from Morinda lucida
- Authors: Chithambo, Bertha
- Date: 2017
- Subjects: Botanical chemistry , Anthraquinones , Antimalarials , Rubiaceae -- Therapeutic use , Malaria -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/45730 , vital:25535
- Description: Antimalarial activities of secondary metabolites from Morinda lucida (Rubiaceae), were investigated. Even though M. lucida is traditionally used to treat malaria, diabetes, jaundice, hypertension, dysentery and many other diseases, the compounds in this plant have not yet been fully investigated and characterised. Most of the studies that have been done on this plant focused on the medicinal properties of the crude extracts but have not gone further to isolate and characterise the compounds. In this study, the methanol - dichloromethane crude extract from the bark of M. lucida was fractionated into fractions 1-8. Fractions 2-5 were purified in order to isolate active secondary metabolites. The isolated pure compounds were characterised and identified. An in vitro antimalarial assay was carried out on the crude extract, fractions, pure compounds and solutions made from different combinations of pure compounds using the parasite lactate dehydrogenase (pLDH) assay. An IC50 done on the methanolic crude extract gave a value of 25 µg/mL. The % cell viability for the crude extract in cell toxicity assay remained at 100%. Each of the pure compounds tested had very little activity. Their activities were increased when samples from the different compounds were mixed. One of these mixtures reduced malaria viability to about 22 % at 20 µM and gave an IC50 value of 17 µM. Antibacterial assays were also carried out on the crude extract and fractions. Fractions 2 and 3 were relatively active (MIC values ranging between 125-1000 µg/mL) against M. cattarhalis and E. faecalis. Fraction 2 was also the most active on S. typhimurium and S. aureus (MIC value of 1000 µg/mL) compared with the other fractions. This same fraction also showed some activity against M. tuberculosis with MIC90 and MIC99 values of 40.9 and 46.3 µg/mL respectively in an anti-tuberculosis assay.The following compounds, comprising of iridoids (asperuloside and asperulosidic acid), terpenoids (stigmasterol, P-sitosterol, campesterol, lanosterol and cycloartenol) and anthraquinones [5,15-O-dimethylmorindol, 1,7-dihydroxy-2-methoxy-5-(methoxymethyl) anthraquinone and 1,6-dihydroxy-2-methoxy-5-(methoxymethyl)anthraquinone], were isolated. All these compounds have been isolated from different plants before with the exception of 1,7-dihydroxy-2-methoxy-5-(methoxymethyl)anthraquinone and 1,6-dihydroxy-2-methoxy-5-(methoxymethyl)anthraquinone which were tentatively assigned the structures due to insufficient data. To the best of our knowledge, this is the first report on the identification of all of the mentioned compounds, with the exception of ß-sitosterol and stigmasterol, from M. lucida. Molecular docking was performed on one of the isolated anthraquinones (5,15-O- dimethylmorindol) to check if it can bind to cytochrome bci, a known target for atovaquone. This compound interacted with the same amino acids that atovaquone, a well known antimalarial agent, interacted with on cytochrome bc1 indicating a possible similar mode of action.
- Full Text:
- Date Issued: 2017
- Authors: Chithambo, Bertha
- Date: 2017
- Subjects: Botanical chemistry , Anthraquinones , Antimalarials , Rubiaceae -- Therapeutic use , Malaria -- Treatment
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/45730 , vital:25535
- Description: Antimalarial activities of secondary metabolites from Morinda lucida (Rubiaceae), were investigated. Even though M. lucida is traditionally used to treat malaria, diabetes, jaundice, hypertension, dysentery and many other diseases, the compounds in this plant have not yet been fully investigated and characterised. Most of the studies that have been done on this plant focused on the medicinal properties of the crude extracts but have not gone further to isolate and characterise the compounds. In this study, the methanol - dichloromethane crude extract from the bark of M. lucida was fractionated into fractions 1-8. Fractions 2-5 were purified in order to isolate active secondary metabolites. The isolated pure compounds were characterised and identified. An in vitro antimalarial assay was carried out on the crude extract, fractions, pure compounds and solutions made from different combinations of pure compounds using the parasite lactate dehydrogenase (pLDH) assay. An IC50 done on the methanolic crude extract gave a value of 25 µg/mL. The % cell viability for the crude extract in cell toxicity assay remained at 100%. Each of the pure compounds tested had very little activity. Their activities were increased when samples from the different compounds were mixed. One of these mixtures reduced malaria viability to about 22 % at 20 µM and gave an IC50 value of 17 µM. Antibacterial assays were also carried out on the crude extract and fractions. Fractions 2 and 3 were relatively active (MIC values ranging between 125-1000 µg/mL) against M. cattarhalis and E. faecalis. Fraction 2 was also the most active on S. typhimurium and S. aureus (MIC value of 1000 µg/mL) compared with the other fractions. This same fraction also showed some activity against M. tuberculosis with MIC90 and MIC99 values of 40.9 and 46.3 µg/mL respectively in an anti-tuberculosis assay.The following compounds, comprising of iridoids (asperuloside and asperulosidic acid), terpenoids (stigmasterol, P-sitosterol, campesterol, lanosterol and cycloartenol) and anthraquinones [5,15-O-dimethylmorindol, 1,7-dihydroxy-2-methoxy-5-(methoxymethyl) anthraquinone and 1,6-dihydroxy-2-methoxy-5-(methoxymethyl)anthraquinone], were isolated. All these compounds have been isolated from different plants before with the exception of 1,7-dihydroxy-2-methoxy-5-(methoxymethyl)anthraquinone and 1,6-dihydroxy-2-methoxy-5-(methoxymethyl)anthraquinone which were tentatively assigned the structures due to insufficient data. To the best of our knowledge, this is the first report on the identification of all of the mentioned compounds, with the exception of ß-sitosterol and stigmasterol, from M. lucida. Molecular docking was performed on one of the isolated anthraquinones (5,15-O- dimethylmorindol) to check if it can bind to cytochrome bci, a known target for atovaquone. This compound interacted with the same amino acids that atovaquone, a well known antimalarial agent, interacted with on cytochrome bc1 indicating a possible similar mode of action.
- Full Text:
- Date Issued: 2017
Antimicrobial activity of selected plants and their combined preparations against pathogens causing respiratory infections
- Authors: Onyebuchi, Ukwuoma Collins
- Date: 2017
- Subjects: Anti-infective agents , Respiratory infections -- Alternative treatment
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/21197 , vital:29455
- Description: Bacterial infection of the respiratory system is one of the leading causes of death in the world’s population, killing over four million people annually. Treatment of respiratory infections is usually by antibiotics administration. The emergence of multi-drug-resistant pathogens has led to the search for more effective therapeutic agents especially from medicinal plants, as compounds from plants have been shown to possess some therapeutic potential. The aim of this study is to determine the antimicrobial activity of three plants, Tetradenia riparia, Leonotis leonurus and Salvia africana-lutea and the activity of their various combined preparations against 27 pathogens usually associated with respiratory ailments. Various solvents were used for extraction of the dried powdered plant materials. The agar disc diffusion antimicrobial assay and the micro-dilution assay methods were used to determine the inhibitory activity and the minimum inhibitory concentration of the plant extracts. The nature of phytochemicals present in the extracts was determined by thin layer chromatography. The results obtained in this study, showed that ethanol produced the highest average extract yield in both the individual and combined plant preparations. A two-way analysis of variance for the disc diffusion assay showed no significant difference in the inhibition zones (Appendix 1 and 2). MIC of 0.8 mg/ml was obtained with S. africana-lutea against S. pneumoniae ATCC 49619 and B. cereus ATCC 10976 strains, indicating a strong antibacterial activity. Synergistic interaction (FIC index ranging from 0.20 – 0.50) and a strong antimicrobial activity (MIC values ranging from 0.4 – 0.8 mg/ml), was obtained with the acetone extract of the 1:1 combination of L. leonurus with S. africana-lutea. The XEA and CEF solvent systems eluted the most number of compound spots and produced the best separations. The results obtained in this study validate the traditional use of these plants and their combinations for the treatment of respiratory ailments.
- Full Text:
- Date Issued: 2017
- Authors: Onyebuchi, Ukwuoma Collins
- Date: 2017
- Subjects: Anti-infective agents , Respiratory infections -- Alternative treatment
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/21197 , vital:29455
- Description: Bacterial infection of the respiratory system is one of the leading causes of death in the world’s population, killing over four million people annually. Treatment of respiratory infections is usually by antibiotics administration. The emergence of multi-drug-resistant pathogens has led to the search for more effective therapeutic agents especially from medicinal plants, as compounds from plants have been shown to possess some therapeutic potential. The aim of this study is to determine the antimicrobial activity of three plants, Tetradenia riparia, Leonotis leonurus and Salvia africana-lutea and the activity of their various combined preparations against 27 pathogens usually associated with respiratory ailments. Various solvents were used for extraction of the dried powdered plant materials. The agar disc diffusion antimicrobial assay and the micro-dilution assay methods were used to determine the inhibitory activity and the minimum inhibitory concentration of the plant extracts. The nature of phytochemicals present in the extracts was determined by thin layer chromatography. The results obtained in this study, showed that ethanol produced the highest average extract yield in both the individual and combined plant preparations. A two-way analysis of variance for the disc diffusion assay showed no significant difference in the inhibition zones (Appendix 1 and 2). MIC of 0.8 mg/ml was obtained with S. africana-lutea against S. pneumoniae ATCC 49619 and B. cereus ATCC 10976 strains, indicating a strong antibacterial activity. Synergistic interaction (FIC index ranging from 0.20 – 0.50) and a strong antimicrobial activity (MIC values ranging from 0.4 – 0.8 mg/ml), was obtained with the acetone extract of the 1:1 combination of L. leonurus with S. africana-lutea. The XEA and CEF solvent systems eluted the most number of compound spots and produced the best separations. The results obtained in this study validate the traditional use of these plants and their combinations for the treatment of respiratory ailments.
- Full Text:
- Date Issued: 2017
Applicability of putative probiotic bacteria to replace antibiotics as growth promoters in commercial and indigenous piglets
- Authors: Dlamini, Ziyanda Confidence
- Date: 2017
- Subjects: Antibiotics , Dietary supplements , Piglets
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11428 , vital:39071
- Description: Antibiotic use in pig production contributes to development of antimicrobial resistance in food animals and risk of antibiotic residues in animal food products. The use of probiotics appears to be the potential alternative to antibiotics. This work is designed to validate the applicability of administered direct-fed putative probiotic strains of Lactobacillus reuteri ZJ625, Lactobacillus reuteri VB4, Lactobacillus salivarius ZJ614 and Streptococcus salivarius NBCR 13956 on growth performance, hematological parameters, and antibody stimulation in weaned commercial and indigenous pigs. Forty-five weaned piglets were divided into five treatment experimental groups as follows: Diet with: antibiotic (PC), No antibiotic and no probiotic (NC), Probiotic (P1) (P2) combination of probiotics (P3). Piglets’ performance were monitored during the trial. Faecal and ileum samples were collected for microbial count analysis. Blood samples were collected from the sacrificed piglets at the end of the trial, for the hematological and biochemical analysis and probiotics ability to stimulate immunoglobulin G (IgG). Four probiotic strains were tested for cell surface hydrophobicity against xylene, chloroform and ethyl acetate. The strains were also tested for auto-aggregation and co-aggregation abilities. Enterococcus faecalis ATCC 29212 was used as a control pathogen in the co-aggregation ability test. The probiotic strains were also screened for presence of virulence and resistance genes. DNA was extracted from all the four probiotic strains using ZR Fungal/Bacterial DNA MiniPepTM (Zymo Research, USA) following manufacturer’s instructions. The DNA samples were later amplified in PCR reactions with specific primers to detect virulence genes of adhesion collagen protein (ace), aggregation substances (agg and asa); antibiotic resistance genes of: Vancomycin vanA, Vancomycin vanC1 and Vancomycin vanC2/3. The data was analyzed by one-way ANOVA using SAS statistics software (SAS 9.3) (2003). Results from the study revealed that supplementation of probiotics had no effect on feed intake (FI) in all of the experimental groups. However, supplementation of probiotics in P3 treatment resulted in greater average daily gain (ADG) and improved feed conversion ratio (FCR) of weaned piglets (p < 0.05). Microbial count of fecal samples from all the treatment groups did not differ while ileum samples had lower enteric bacteria in P3 group as compared to other treatments. Concentration of albumin, globulin, neutrophils and basophils were high in NC treatment compared to other treatments. (p < 0.05). IgG concentration was highest in P3 compared to other treatment (p < 0.05). All probiotics strains showed high hydrophobicity to all solvents used in the test. Cell Surface Hydrophobic was highest in xylene (78percent – 84percent), followed by chloroform (68percent – 75percent) and lowest in ethyl acetate (52percent - 60percent). All of the test strains showed high auto-aggregation ability after 4 hr of incubation. L .reuteri VB4 exhibited highest auto-aggregation ability of 70percent, while the least auto-aggregation ability of 60percent was observed for L. salivarius ZJ614. In the co-aggregation assays, all probiotic bacterial strains exhibited a strong co-aggregation of 45percent to 56percent after 4 hr of incubation at 37 °C. L. reuteri VB4 exhibited highest co-aggregation ability while L. salivarius ZJ614 exhibited the lowest co-aggregation ability. No presence of virulence genes ace and asa was detected in all of the putative probiotic strains, but agg virulence gene was detected in L. reuteri VB4 strains. L. reuteri VB4 and S. salivarius NBRC13956 had resistance genes vanC 2/3 and vanC1, respectively. Overall, the results from this study, suggest that the candidate probiotics strains have enhanced the growth and measured blood parameters of the weaned piglets used in these experiments, and also, the probiotic strains have the abilities to initiate the stimulation of IgG. Probiotics could be used as a novel alternative to antibiotics in the animal nutrition and production, with the abilities to confer health benefits and promote growth. The outcome of the research advocates that these probiotics will be beneficial to pig production, and might outcompete the current antibiotics in use as growth promoters. One of the major advantages of probiotics to pig industry is the production of antibiotic free and good quality pork meat to local and international consumers, thus, enhancing South African Pork industry.
- Full Text:
- Date Issued: 2017
- Authors: Dlamini, Ziyanda Confidence
- Date: 2017
- Subjects: Antibiotics , Dietary supplements , Piglets
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11428 , vital:39071
- Description: Antibiotic use in pig production contributes to development of antimicrobial resistance in food animals and risk of antibiotic residues in animal food products. The use of probiotics appears to be the potential alternative to antibiotics. This work is designed to validate the applicability of administered direct-fed putative probiotic strains of Lactobacillus reuteri ZJ625, Lactobacillus reuteri VB4, Lactobacillus salivarius ZJ614 and Streptococcus salivarius NBCR 13956 on growth performance, hematological parameters, and antibody stimulation in weaned commercial and indigenous pigs. Forty-five weaned piglets were divided into five treatment experimental groups as follows: Diet with: antibiotic (PC), No antibiotic and no probiotic (NC), Probiotic (P1) (P2) combination of probiotics (P3). Piglets’ performance were monitored during the trial. Faecal and ileum samples were collected for microbial count analysis. Blood samples were collected from the sacrificed piglets at the end of the trial, for the hematological and biochemical analysis and probiotics ability to stimulate immunoglobulin G (IgG). Four probiotic strains were tested for cell surface hydrophobicity against xylene, chloroform and ethyl acetate. The strains were also tested for auto-aggregation and co-aggregation abilities. Enterococcus faecalis ATCC 29212 was used as a control pathogen in the co-aggregation ability test. The probiotic strains were also screened for presence of virulence and resistance genes. DNA was extracted from all the four probiotic strains using ZR Fungal/Bacterial DNA MiniPepTM (Zymo Research, USA) following manufacturer’s instructions. The DNA samples were later amplified in PCR reactions with specific primers to detect virulence genes of adhesion collagen protein (ace), aggregation substances (agg and asa); antibiotic resistance genes of: Vancomycin vanA, Vancomycin vanC1 and Vancomycin vanC2/3. The data was analyzed by one-way ANOVA using SAS statistics software (SAS 9.3) (2003). Results from the study revealed that supplementation of probiotics had no effect on feed intake (FI) in all of the experimental groups. However, supplementation of probiotics in P3 treatment resulted in greater average daily gain (ADG) and improved feed conversion ratio (FCR) of weaned piglets (p < 0.05). Microbial count of fecal samples from all the treatment groups did not differ while ileum samples had lower enteric bacteria in P3 group as compared to other treatments. Concentration of albumin, globulin, neutrophils and basophils were high in NC treatment compared to other treatments. (p < 0.05). IgG concentration was highest in P3 compared to other treatment (p < 0.05). All probiotics strains showed high hydrophobicity to all solvents used in the test. Cell Surface Hydrophobic was highest in xylene (78percent – 84percent), followed by chloroform (68percent – 75percent) and lowest in ethyl acetate (52percent - 60percent). All of the test strains showed high auto-aggregation ability after 4 hr of incubation. L .reuteri VB4 exhibited highest auto-aggregation ability of 70percent, while the least auto-aggregation ability of 60percent was observed for L. salivarius ZJ614. In the co-aggregation assays, all probiotic bacterial strains exhibited a strong co-aggregation of 45percent to 56percent after 4 hr of incubation at 37 °C. L. reuteri VB4 exhibited highest co-aggregation ability while L. salivarius ZJ614 exhibited the lowest co-aggregation ability. No presence of virulence genes ace and asa was detected in all of the putative probiotic strains, but agg virulence gene was detected in L. reuteri VB4 strains. L. reuteri VB4 and S. salivarius NBRC13956 had resistance genes vanC 2/3 and vanC1, respectively. Overall, the results from this study, suggest that the candidate probiotics strains have enhanced the growth and measured blood parameters of the weaned piglets used in these experiments, and also, the probiotic strains have the abilities to initiate the stimulation of IgG. Probiotics could be used as a novel alternative to antibiotics in the animal nutrition and production, with the abilities to confer health benefits and promote growth. The outcome of the research advocates that these probiotics will be beneficial to pig production, and might outcompete the current antibiotics in use as growth promoters. One of the major advantages of probiotics to pig industry is the production of antibiotic free and good quality pork meat to local and international consumers, thus, enhancing South African Pork industry.
- Full Text:
- Date Issued: 2017
Appointment and promotion disputes in the public education sector
- Authors: Rustin, Jonavon Keith
- Date: 2017
- Subjects: Labor disputes -- South Africa Education -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10948/20277 , vital:29182
- Description: Promotions and appointments in the Public Education Sector had led to many disputes that were referred to the Education Labour Relations Council (the "ELRC"). For a long time most disputes referred to the ELRC concerned promotion disputes. In this treatise the applicable law relating to the promotions and appointments is described and evaluated. Shortly before the completion of the treatise a collective agreement was concluded under the auspices of the ELRC with a view to regulating appointments and promotions. The historical background is traced and the present legislative framework is explained. Thereafter the ELRC Resolutions dealing with the topic discussed and the new collective agreement is unpacked.
- Full Text: false
- Date Issued: 2017
- Authors: Rustin, Jonavon Keith
- Date: 2017
- Subjects: Labor disputes -- South Africa Education -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10948/20277 , vital:29182
- Description: Promotions and appointments in the Public Education Sector had led to many disputes that were referred to the Education Labour Relations Council (the "ELRC"). For a long time most disputes referred to the ELRC concerned promotion disputes. In this treatise the applicable law relating to the promotions and appointments is described and evaluated. Shortly before the completion of the treatise a collective agreement was concluded under the auspices of the ELRC with a view to regulating appointments and promotions. The historical background is traced and the present legislative framework is explained. Thereafter the ELRC Resolutions dealing with the topic discussed and the new collective agreement is unpacked.
- Full Text: false
- Date Issued: 2017
Appropriate integration of workers with physical limitations into a manual workplace – development of an assessment tool
- Authors: Pearson, Jessie T
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/8209 , vital:21368
- Description: Background: People with physical limitations can contribute significantly to society and the economy, however, barriers to full and effective participation in the labour market often hinder decent employment. In light of this, placement decisions of impaired workers should be based on detailed information of the nature of the jobs available, as well as individual capabilities of the worker. An ergonomics approach to design attempts to achieve an appropriate balance between the capabilities of the worker and the requirements of the task and uses this balance to improve productivity and encourage physical and mental well-being, job satisfaction and safety. A specific analysis tool which can be applied to various workplaces and jobs, and provide information for decisions regarding placement of physically limited workers, will help to increase the percentage of correct placement in an appropriate workplace, resulting in optimum productivity and worker safety. Methods: An assessment tool which allows matching of job requirements and worker capabilities was developed based on a theoretical framework from Mattison and Goebel (2007), as well as principles defined by Almgren and Schaurig (2012) and Demura and Nakada (2010). The tool assesses range of motion, force and time components of the physical requirements of different tasks involved in the job, as well as movement capabilities and limitations of the worker. The tool was pilot tested in a case study with an above the knee amputee working at a research facility. Results: The tool successfully provided information regarding the matching of the work to the identified job. The output of the tool highlighted two tasks which would place the worker at risk due to physical requirements of the tasks being greater than movement capabilities of the worker. These tasks need to be further investigated to determine if accommodations can be made to assist the worker in safely performing the task, or if the job is not suitable for the worker. Conclusions: The tool developed was useful in providing information to inform appropriate placement of the physically limited worker. Further research needs to be done to validate and determine reliability of the tool.
- Full Text:
- Date Issued: 2017
- Authors: Pearson, Jessie T
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/8209 , vital:21368
- Description: Background: People with physical limitations can contribute significantly to society and the economy, however, barriers to full and effective participation in the labour market often hinder decent employment. In light of this, placement decisions of impaired workers should be based on detailed information of the nature of the jobs available, as well as individual capabilities of the worker. An ergonomics approach to design attempts to achieve an appropriate balance between the capabilities of the worker and the requirements of the task and uses this balance to improve productivity and encourage physical and mental well-being, job satisfaction and safety. A specific analysis tool which can be applied to various workplaces and jobs, and provide information for decisions regarding placement of physically limited workers, will help to increase the percentage of correct placement in an appropriate workplace, resulting in optimum productivity and worker safety. Methods: An assessment tool which allows matching of job requirements and worker capabilities was developed based on a theoretical framework from Mattison and Goebel (2007), as well as principles defined by Almgren and Schaurig (2012) and Demura and Nakada (2010). The tool assesses range of motion, force and time components of the physical requirements of different tasks involved in the job, as well as movement capabilities and limitations of the worker. The tool was pilot tested in a case study with an above the knee amputee working at a research facility. Results: The tool successfully provided information regarding the matching of the work to the identified job. The output of the tool highlighted two tasks which would place the worker at risk due to physical requirements of the tasks being greater than movement capabilities of the worker. These tasks need to be further investigated to determine if accommodations can be made to assist the worker in safely performing the task, or if the job is not suitable for the worker. Conclusions: The tool developed was useful in providing information to inform appropriate placement of the physically limited worker. Further research needs to be done to validate and determine reliability of the tool.
- Full Text:
- Date Issued: 2017
Aspects of the feeding biology of the copepod Pseudodiaptomus hessei (Copepoda: Calanoida) under culture conditions
- Authors: Mzozo, Ziyanda
- Date: 2017
- Subjects: Copepoda Microbial ecology Fishes -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4727 , vital:28502
- Description: This study aimed to investigate the feeding behaviour of the calanoid copepod, Pseudodiaptomus hessei, particularly whether it prefers to feed on a planktonic or benthic food source. The effect of different microalgae species on the feeding preference, ingestion, and gut evacuation rate were investigated. Two microalgae species (Isochrysis galbana and Tetraselmis suecica) were used, to test gut fullness and gut evacuation of P. hessei. The copepods were starved for 6 h and allowed to feed on monalgae diets, I .galbana and T. suecica, and a 1:1 binary diet mixture of T. suecica and I. galbana. The gut fullness and gut evacuation rates were determined by observing under the dissecting microscope and gut content percentage was recorded (as 0, 25, 50, 75 or 100 percent) along with copepod sex. Copepods that feed on T. suecica fill their gut after 30 min, while those that feed on I. galbana do so after 40 min. There was a significant difference (p= 0.02) between sexes with males filling their gut faster than females. However, copepods that fed on I. galbana evacuated their gut content completely after 30 min, while those fed on T suecica evacuated theirs after 40 min. There was no difference between males and females for gut evacuation. Even though there was high gut fullness rate when P. hessei was feeding on T. suecica, I. galbana is recommended as the best mono-algae diet to culture P. hessei. The feeding behaviour of P. hessei was investigated, as to whether it prefers to feed on a planktonic or benthic food source. Copepods were starved for 3 h and then allowed to feed on two microalgae species (I. galbana and T. suecica), one presented as a benthic and other as planktonic. Controls included swapping the modes of presentation for each algae species. Ingested microalgae species were quantified using real-time PCR, with threshold cycles interpreted as relative abundance ratio (planktonic microalgae divided by benthic microalgae species). Pseudodiaptomus hessei preferred to feed on planktonic food sources initially as there was a difference between planktonic and benthic ingested food (p=0.026). Copepods shifted from planktonic to benthic food sources after 80 min of feeding planktonically. Planktonic food sources were the preferred choice for P. hessei regardless of microalgae species offered. The results from this study also confirm that P. hessei feed on a benthic food source during the day under culture conditions. This information can be used as baseline information for aquaculturists to rear the species as live feed for marine fish larvae.
- Full Text:
- Date Issued: 2017
- Authors: Mzozo, Ziyanda
- Date: 2017
- Subjects: Copepoda Microbial ecology Fishes -- Feeding and feeds
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4727 , vital:28502
- Description: This study aimed to investigate the feeding behaviour of the calanoid copepod, Pseudodiaptomus hessei, particularly whether it prefers to feed on a planktonic or benthic food source. The effect of different microalgae species on the feeding preference, ingestion, and gut evacuation rate were investigated. Two microalgae species (Isochrysis galbana and Tetraselmis suecica) were used, to test gut fullness and gut evacuation of P. hessei. The copepods were starved for 6 h and allowed to feed on monalgae diets, I .galbana and T. suecica, and a 1:1 binary diet mixture of T. suecica and I. galbana. The gut fullness and gut evacuation rates were determined by observing under the dissecting microscope and gut content percentage was recorded (as 0, 25, 50, 75 or 100 percent) along with copepod sex. Copepods that feed on T. suecica fill their gut after 30 min, while those that feed on I. galbana do so after 40 min. There was a significant difference (p= 0.02) between sexes with males filling their gut faster than females. However, copepods that fed on I. galbana evacuated their gut content completely after 30 min, while those fed on T suecica evacuated theirs after 40 min. There was no difference between males and females for gut evacuation. Even though there was high gut fullness rate when P. hessei was feeding on T. suecica, I. galbana is recommended as the best mono-algae diet to culture P. hessei. The feeding behaviour of P. hessei was investigated, as to whether it prefers to feed on a planktonic or benthic food source. Copepods were starved for 3 h and then allowed to feed on two microalgae species (I. galbana and T. suecica), one presented as a benthic and other as planktonic. Controls included swapping the modes of presentation for each algae species. Ingested microalgae species were quantified using real-time PCR, with threshold cycles interpreted as relative abundance ratio (planktonic microalgae divided by benthic microalgae species). Pseudodiaptomus hessei preferred to feed on planktonic food sources initially as there was a difference between planktonic and benthic ingested food (p=0.026). Copepods shifted from planktonic to benthic food sources after 80 min of feeding planktonically. Planktonic food sources were the preferred choice for P. hessei regardless of microalgae species offered. The results from this study also confirm that P. hessei feed on a benthic food source during the day under culture conditions. This information can be used as baseline information for aquaculturists to rear the species as live feed for marine fish larvae.
- Full Text:
- Date Issued: 2017
Assessing cultural readiness for lean implementation at an automotive component manufacturer in Port Elizabeth
- Levendal, Arend Randolph Dimitre
- Authors: Levendal, Arend Randolph Dimitre
- Date: 2017
- Subjects: Organizational effectiveness Organizational change , Corporate culture Motor industry -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/18145 , vital:28580
- Description: Automotive component manufacturers face significant competitive challenges in the global market and are constantly looking for means to improve their competitive advantage. Organisations then often acquire lean tools as an attractive option to achieve this. Research has however highlighted that the underlying “Lean Culture” is what is really necessary for organisations to achieve and maintain a competitive advantage. According to Rother (2010) lean implementation can be seen as a project or an initiation of an on- going development process where learning is taking place. This implementation implies a change in organisational culture from its existing state to a state where it reflects a lean culture. The literature review into Lean highlights the importance of establishing a Lean Culture. This research relied on an existing Lean Culture Causal Framework to assess cultural readiness for lean implementation at an automotive component manufacturer in Port Elizabeth (Company X). This was done utilising an empirical study which relied on an existing questionnaire associated with the said Lean Culture Causal Frame work. This Framework focuses on four broad categories of leadership actions; Awareness, Engagement, Consistency and Accountability.
- Full Text:
- Date Issued: 2017
- Authors: Levendal, Arend Randolph Dimitre
- Date: 2017
- Subjects: Organizational effectiveness Organizational change , Corporate culture Motor industry -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/18145 , vital:28580
- Description: Automotive component manufacturers face significant competitive challenges in the global market and are constantly looking for means to improve their competitive advantage. Organisations then often acquire lean tools as an attractive option to achieve this. Research has however highlighted that the underlying “Lean Culture” is what is really necessary for organisations to achieve and maintain a competitive advantage. According to Rother (2010) lean implementation can be seen as a project or an initiation of an on- going development process where learning is taking place. This implementation implies a change in organisational culture from its existing state to a state where it reflects a lean culture. The literature review into Lean highlights the importance of establishing a Lean Culture. This research relied on an existing Lean Culture Causal Framework to assess cultural readiness for lean implementation at an automotive component manufacturer in Port Elizabeth (Company X). This was done utilising an empirical study which relied on an existing questionnaire associated with the said Lean Culture Causal Frame work. This Framework focuses on four broad categories of leadership actions; Awareness, Engagement, Consistency and Accountability.
- Full Text:
- Date Issued: 2017
Assessing MODIS evapotranspiration data for hydrological modelling in South Africa
- Mazibuko, Sbongiseni Christian
- Authors: Mazibuko, Sbongiseni Christian
- Date: 2017
- Subjects: Evapotranspiration , Evapotranspiration -- Measurement , Hydrologic models , Hydrologic models -- South Africa , MODIS (Spectroradiometer)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/8009 , vital:21334
- Description: Evapotranspiration as a major component of the water balance has been identified as a key factor in hydrological modelling. Water management can be improved by means of increased use of reliable methods for estimating evapotranspiration. The limited availability of measured climate and discharge data sets, particularly in the developing world, restricts the reliability of hydrological models in these regions. Furthermore, rapid changes in hydrological systems with increasing development mean uncertainties in water resource estimation are growing. These changes are related to the modification of catchment hydrological processes with increasing human activity. Dealing with data uncertainty and quantifying the impacts of catchment activities are significant challenges that scientists in the field of hydrology face today. Uncertainties in hydrometeorological data are associated with poor observation networks that provide data at point scales which are not adequately representative of the inherent heterogeneity within catchment processes. Using uncertain data in model applications reduces the predictive power of hydrological models as well as the ability to validate the model outcomes. This study examines the potential of using remote sensing-based evapotranspiration data to reduce uncertainty in the climatic forcing data and constraining the output of a rainfall-runoff hydrological model. It is common to use fixed seasonally variable potential evapotranspiration (PET) instead of temporally varying PET data as inputs to standard rainfall-runoff models. Part of the reason is that there are relatively few stations available to measure a variety of meteorological input data needed to compute PET, as well as the apparent lack of sensitivity of rainfall-runoff models to different types of PET inputs. As hydrometeorological data become more readily available through the use of earth observation systems, it is important to determine whether rainfall-runoff models are sensitive to time-varying PET derived from these earth observations systems. Further potential includes the use of actual evapotranspiration (ETa) from this type of data to constrain model outputs and improve model realism. It is assumed that a better representation of evapotranspiration demands could improve the efficiency of models, and this study explores some of these issues. The study used evapotranspiration estimates (PET and ETa) from the MOD16 global product with one of the most widely used hydrological models in South Africa. The investigation included applying the Pitman model in a number of case study catchments located in different climatic regions of the country. The main objectives of the study included (i) the establishment of behavioural model parameter sets that generate acceptable hydrological response under both naturalised and present-day conditions, (ii) the use of time-varying PET estimates derived from MOD16 data to force the model, and (iii) the use of MOD16 ETa estimates to constrain model-simulated ETa. Before examining the use of different PET forcing data in the model, a two-step modelling approached was employed both a single-run and an uncertainty version of the Pitman model. During the first step (using a single-run version), available information on catchment physical properties and regionalised groundwater recharge together with model calibration principles were used to develop model functionality understanding and establish initial parameter sets. The outcomes from the first step were used to define uncertain parameter ranges for the use in the uncertainty version of the Pitman model (second step). Further, catchment water uses were quantified to ensure comparability with present-day flow conditions represented by the stream flow records. The effects of forcing the Pitman model with MOD16-based time-varying PET data inputs were evaluated using static and dynamic sensitivity analysis approaches. In the static approach, parameter sets calibrated using fixed seasonal distributions of PET data remain unchanged when forcing the model with other forms of PET, whereas in the dynamic method, the model is recalibrated with changing PET inputs. In both approaches, model sensitivity was assessed by comparing objective function statistics of reference flow simulations with those simulations incorporating changing PET data inputs. The use of the MOD16 ETa data to constrain model- simulated evapotranspiration losses was conducted by calibrating the parameters such that the simulated-ETa matched the evapotranspiration loss estimated from the MOD16 data. Despite issues around model equifinality and significant uncertainty within water use information, the Pitman model simulations were generally satisfactory and compared with observed stream flow data where available. The use of time-varying PET data does not improve the efficiency of the model when both static and dynamic sensitivity approaches are used. This was highly expected with the static approach where fixed model parameter sets do not account for the changes in evapotranspiration demands. However, with the dynamic approach, it was difficult to conclude why the model efficiency did not improve given the flexibility of the model to achieve appropriate parameter sets to different forms of PET. The study noted that the insensitivity of the model to changes in PET demands could be due to uncertainties in the model structure and MOD16 data. Attempts to constrain the model-simulated actual evapotranspiration with MOD16 ETa estimates were hampered by large errors in the MOD16 data and resulted in the non-closure of the catchment annual water balance, even when likely errors in the other components of the water balance were accounted for. There is still a great deal of work that needs to be done to reduce uncertainties associated with the use of earth observation data in hydrological modelling. This study has identified some of the specific gaps within the application of evapotranspiration data from earth observation information. While the MOD16 data applied with the Pitman model did not achieve improved simulations, the study has demonstrated the enormous potential of the data product in the future should the identified uncertainties be resolved. Lastly, the investigation highlighted some of the possible model structural uncertainties specifically associated with the simplified soil-moisture accounting routines within the model. It is possible that amending the model structure through investigating the dynamics of the relationship between soil moisture and evapotranspiration losses would assist in the improved utilisation of earth observation products related to the MOD16 ET data.
- Full Text:
- Date Issued: 2017
- Authors: Mazibuko, Sbongiseni Christian
- Date: 2017
- Subjects: Evapotranspiration , Evapotranspiration -- Measurement , Hydrologic models , Hydrologic models -- South Africa , MODIS (Spectroradiometer)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/8009 , vital:21334
- Description: Evapotranspiration as a major component of the water balance has been identified as a key factor in hydrological modelling. Water management can be improved by means of increased use of reliable methods for estimating evapotranspiration. The limited availability of measured climate and discharge data sets, particularly in the developing world, restricts the reliability of hydrological models in these regions. Furthermore, rapid changes in hydrological systems with increasing development mean uncertainties in water resource estimation are growing. These changes are related to the modification of catchment hydrological processes with increasing human activity. Dealing with data uncertainty and quantifying the impacts of catchment activities are significant challenges that scientists in the field of hydrology face today. Uncertainties in hydrometeorological data are associated with poor observation networks that provide data at point scales which are not adequately representative of the inherent heterogeneity within catchment processes. Using uncertain data in model applications reduces the predictive power of hydrological models as well as the ability to validate the model outcomes. This study examines the potential of using remote sensing-based evapotranspiration data to reduce uncertainty in the climatic forcing data and constraining the output of a rainfall-runoff hydrological model. It is common to use fixed seasonally variable potential evapotranspiration (PET) instead of temporally varying PET data as inputs to standard rainfall-runoff models. Part of the reason is that there are relatively few stations available to measure a variety of meteorological input data needed to compute PET, as well as the apparent lack of sensitivity of rainfall-runoff models to different types of PET inputs. As hydrometeorological data become more readily available through the use of earth observation systems, it is important to determine whether rainfall-runoff models are sensitive to time-varying PET derived from these earth observations systems. Further potential includes the use of actual evapotranspiration (ETa) from this type of data to constrain model outputs and improve model realism. It is assumed that a better representation of evapotranspiration demands could improve the efficiency of models, and this study explores some of these issues. The study used evapotranspiration estimates (PET and ETa) from the MOD16 global product with one of the most widely used hydrological models in South Africa. The investigation included applying the Pitman model in a number of case study catchments located in different climatic regions of the country. The main objectives of the study included (i) the establishment of behavioural model parameter sets that generate acceptable hydrological response under both naturalised and present-day conditions, (ii) the use of time-varying PET estimates derived from MOD16 data to force the model, and (iii) the use of MOD16 ETa estimates to constrain model-simulated ETa. Before examining the use of different PET forcing data in the model, a two-step modelling approached was employed both a single-run and an uncertainty version of the Pitman model. During the first step (using a single-run version), available information on catchment physical properties and regionalised groundwater recharge together with model calibration principles were used to develop model functionality understanding and establish initial parameter sets. The outcomes from the first step were used to define uncertain parameter ranges for the use in the uncertainty version of the Pitman model (second step). Further, catchment water uses were quantified to ensure comparability with present-day flow conditions represented by the stream flow records. The effects of forcing the Pitman model with MOD16-based time-varying PET data inputs were evaluated using static and dynamic sensitivity analysis approaches. In the static approach, parameter sets calibrated using fixed seasonal distributions of PET data remain unchanged when forcing the model with other forms of PET, whereas in the dynamic method, the model is recalibrated with changing PET inputs. In both approaches, model sensitivity was assessed by comparing objective function statistics of reference flow simulations with those simulations incorporating changing PET data inputs. The use of the MOD16 ETa data to constrain model- simulated evapotranspiration losses was conducted by calibrating the parameters such that the simulated-ETa matched the evapotranspiration loss estimated from the MOD16 data. Despite issues around model equifinality and significant uncertainty within water use information, the Pitman model simulations were generally satisfactory and compared with observed stream flow data where available. The use of time-varying PET data does not improve the efficiency of the model when both static and dynamic sensitivity approaches are used. This was highly expected with the static approach where fixed model parameter sets do not account for the changes in evapotranspiration demands. However, with the dynamic approach, it was difficult to conclude why the model efficiency did not improve given the flexibility of the model to achieve appropriate parameter sets to different forms of PET. The study noted that the insensitivity of the model to changes in PET demands could be due to uncertainties in the model structure and MOD16 data. Attempts to constrain the model-simulated actual evapotranspiration with MOD16 ETa estimates were hampered by large errors in the MOD16 data and resulted in the non-closure of the catchment annual water balance, even when likely errors in the other components of the water balance were accounted for. There is still a great deal of work that needs to be done to reduce uncertainties associated with the use of earth observation data in hydrological modelling. This study has identified some of the specific gaps within the application of evapotranspiration data from earth observation information. While the MOD16 data applied with the Pitman model did not achieve improved simulations, the study has demonstrated the enormous potential of the data product in the future should the identified uncertainties be resolved. Lastly, the investigation highlighted some of the possible model structural uncertainties specifically associated with the simplified soil-moisture accounting routines within the model. It is possible that amending the model structure through investigating the dynamics of the relationship between soil moisture and evapotranspiration losses would assist in the improved utilisation of earth observation products related to the MOD16 ET data.
- Full Text:
- Date Issued: 2017
Assessing monitoring and evaluation as the control measure to enhance organisational performance with the reference to the Eastern Cape provincial treasury
- Authors: Tshefu, Siyabulela
- Date: 2017
- Subjects: Civil service -- Labor productivity -- South Africa -- Eastern Cape -- Evaluation Performance standards -- South Africa -- Eastern Cape -- Evaluation , Organizational effectiveness -- South Africa -- Eastern Cape Organizational behavior -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/21373 , vital:29505
- Description: The growing demand for governments and organisations to demonstrate principles of accountability, transparency and participatory decision making, which are the cornerstones of good governance, has fostered renewed efforts to transform the public service to ultimately produce tangible results and meet the needs of the beneficiaries of service delivery. Effective performance management practised across the entire organization in an integrated, iterative and sustained way that can help public service organizations overcome the challenges and deliver more with less. This study focuses on the assessment of monitoring and evaluation as the control measure to enhance organisational performance with the reference to the Eastern Cape Provincial Treasury and assess critical role in supporting performance management and also provides methodological options to support performance management. Monitoring and Evaluation (M&E) are management activities that are necessary to ensure the achievement of policy goals in the form of concrete results. The study revealed that the current M and E system is not effective in that there are no clearly defined standards of what a quarterly progress report entail, especially the portfolio of evidence and because the main problem stems from the definition of what constitutes departmental performance. In determining what needs to be done, the effectiveness suffers since we opt for mainly indicators that are “safe”, that the department are sure they can achieve and not necessarily those that will enhance organizational performance. The study revealed that each programme manager should monitor and evaluate his/her processes on a continuous basis without having to wait for M&E unit. M&E unit will then provide an objective evaluation of the process already in place and constant engagement between M&E unit and line management, feedback sessions between staff and M&E unit are essential about the achievement of targets as outlined in the APP and Operational Plan. The study further revealed that there should be continuous meetings to discuss how directorates should sufficiently report on their quarterly targets to avoid inadequate reported information and the department must go step by step in performing activities towards achieving a set vision and on way to the vision, not forgetting to take away risks that may take us to another direction that was not intended as per our vision. The study thus recommends that, inter alia, the department must introduce strong mechanisms to deal with non-implementation of corrective measures regarding under performance and the poor quality of information provided in performance reports related to the performance indicators in the Annual Performance Plans.The introduction of an early warning sign system to warn all programmes when the performance of their planned indicators are not be achieved. The Top Management should continue to use the performance management information as the tool to improve the organisational performance by linking and aligning individual, team and organisational objectives and results, it also provides a means to recognise and reward good performance and to manage under-performance. However the Top Management should be able to conduct in-depth analysis into underperformance to detect whether the underperformance is related to the bad crafting of the indicators or if it relates to the work not done. The department should invest money on training of officials in M&E because it plays a critical role supporting performance management at various levels, in that it contributes to a thinking that is results oriented and also provides methodological options to support performance management. This means that all officials must be capacitated to manage M&E systems in the department that will ensure the production of accurate, objective and reliable information. The M&E unit in the department must facilitate such skills development and provide reasonable technical support where required. The training could be designed to instill a deeper understanding and knowledge of the concepts of M&E and their correct application in order to avoid misunderstandings and misinterpretations which could hinder the achievement of the desired results.
- Full Text:
- Date Issued: 2017
- Authors: Tshefu, Siyabulela
- Date: 2017
- Subjects: Civil service -- Labor productivity -- South Africa -- Eastern Cape -- Evaluation Performance standards -- South Africa -- Eastern Cape -- Evaluation , Organizational effectiveness -- South Africa -- Eastern Cape Organizational behavior -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10948/21373 , vital:29505
- Description: The growing demand for governments and organisations to demonstrate principles of accountability, transparency and participatory decision making, which are the cornerstones of good governance, has fostered renewed efforts to transform the public service to ultimately produce tangible results and meet the needs of the beneficiaries of service delivery. Effective performance management practised across the entire organization in an integrated, iterative and sustained way that can help public service organizations overcome the challenges and deliver more with less. This study focuses on the assessment of monitoring and evaluation as the control measure to enhance organisational performance with the reference to the Eastern Cape Provincial Treasury and assess critical role in supporting performance management and also provides methodological options to support performance management. Monitoring and Evaluation (M&E) are management activities that are necessary to ensure the achievement of policy goals in the form of concrete results. The study revealed that the current M and E system is not effective in that there are no clearly defined standards of what a quarterly progress report entail, especially the portfolio of evidence and because the main problem stems from the definition of what constitutes departmental performance. In determining what needs to be done, the effectiveness suffers since we opt for mainly indicators that are “safe”, that the department are sure they can achieve and not necessarily those that will enhance organizational performance. The study revealed that each programme manager should monitor and evaluate his/her processes on a continuous basis without having to wait for M&E unit. M&E unit will then provide an objective evaluation of the process already in place and constant engagement between M&E unit and line management, feedback sessions between staff and M&E unit are essential about the achievement of targets as outlined in the APP and Operational Plan. The study further revealed that there should be continuous meetings to discuss how directorates should sufficiently report on their quarterly targets to avoid inadequate reported information and the department must go step by step in performing activities towards achieving a set vision and on way to the vision, not forgetting to take away risks that may take us to another direction that was not intended as per our vision. The study thus recommends that, inter alia, the department must introduce strong mechanisms to deal with non-implementation of corrective measures regarding under performance and the poor quality of information provided in performance reports related to the performance indicators in the Annual Performance Plans.The introduction of an early warning sign system to warn all programmes when the performance of their planned indicators are not be achieved. The Top Management should continue to use the performance management information as the tool to improve the organisational performance by linking and aligning individual, team and organisational objectives and results, it also provides a means to recognise and reward good performance and to manage under-performance. However the Top Management should be able to conduct in-depth analysis into underperformance to detect whether the underperformance is related to the bad crafting of the indicators or if it relates to the work not done. The department should invest money on training of officials in M&E because it plays a critical role supporting performance management at various levels, in that it contributes to a thinking that is results oriented and also provides methodological options to support performance management. This means that all officials must be capacitated to manage M&E systems in the department that will ensure the production of accurate, objective and reliable information. The M&E unit in the department must facilitate such skills development and provide reasonable technical support where required. The training could be designed to instill a deeper understanding and knowledge of the concepts of M&E and their correct application in order to avoid misunderstandings and misinterpretations which could hinder the achievement of the desired results.
- Full Text:
- Date Issued: 2017
Assessing selected ecosystem services in urban green spaces in Bulawayo, Zimbabwe
- Ngulani, Thembelihle Tshandapiwa
- Authors: Ngulani, Thembelihle Tshandapiwa
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5856 , vital:20982
- Description: Urbanization has resulted in the building of numerous structures such as buildings and roads which reduces the amount of natural land. Urban space planning has taken this into consideration resulting in planned urban green spaces and remnant land within urban areas. Urban green spaces provide a number of ecosystem services which are beneficial to urban residents. This study sought to determine residents’ use and perception of urban green spaces in Bulawayo, the second largest city in Zimbabwe, and to quantify and value four selected ecosystem services, i.e. carbon sequestration by urban trees, urban heat island amelioration, spiritual services and firewood provision. All ecosystem services were valued using local a variety of direct or substitutive methods. Questionnaires were administered at green spaces to green space users to capture responses on reasons why they use green spaces and their perception of green spaces. Residents’ responses showed that they appreciate green spaces as multidimensional spaces which provide a number of benefits for cultural and provisioning services. The role of the green spaces in providing regulating services was not well appreciated by the residents as they did not directly experience these benefits. An association was revealed between primary purpose of visit to urban green spaces and household income. Residents in areas of medium and high density housing visited green spaces on a daily basis, whereas those in more affluent, low density housing areas visited green spaces less often, i.e. a few times a month Carbon sequestration rate was determined by measuring tree diameter within one year to determine increase in carbon sequestered. Bulawayo’s urban green spaces sequester 3 290 t/C/yr valued at approximately $13 000/yr. There was a significant difference in carbon sequestration by urban trees between formal and informal green spaces with formal green spaces sequestering more carbon. Indigenous trees were shown to sequester more carbon than exotic trees and trees with bigger stem diameter were determined sequester more carbon than trees with small diameter. The effect of urban green spaces on ambient temperature was determined by measuring ambient air temperature in green spaces and built up areas over six months. Urban green spaces in Bulawayo play a role in urban micro-climate regulation by reducing the ambient temperature in the green spaces as well as is built up areas. The mean difference between green spaces and surrounding urban areas was up to 60C, with larger green spaces generally showing larger differences. The green spaces extend their cooling effect to surrounding areas thus reducing the temperatures in surrounding residential areas thus reducing the energy demand used for indoor cooling. To determine why residents worship in green spaces, questionnaires were administered to congregation members to capture reasons why and how often they worship in green spaces, challenges faced by the congregants as well as assistance that can be given by the Bulawayo city council to improve the outdoor worship experience. Green spaces offer ideal places for worship in natural areas for congregants to be in touch with nature. The green spaces are also used by some congregations who ordinarily would worship in buildings but fail to do so due to lack of funds for rent or to purchase or construct a church building to use. The value of Bulawayo’s green spaces spiritual services was determined to be $92.50/ha/yr. Firewood provision was also determined by measuring tree diameter within one year to determine increase in fuelwood. The green spaces showed a significant difference in firewood production among sites. Formal green spaces were shown to produce more firewood as compared to informal green spaces and no difference was determined in growth rates between exotic and indigenous tree species. Bulawayo’s green spaces produce 1.9t/ha/yr of firewood with an ecosystem service value of $340 to $490 /ha/yr. These findings indicate the importance of urban green spaces in Bulawayo. They are multifunctional spaces, providing multiple ecosystem services. The local appreciation of the services provided by urban green spaces differs according to the type of service and location in the city. The value of services provided by green spaces is high, albeit not taken into account in planning decisions.
- Full Text:
- Date Issued: 2017
- Authors: Ngulani, Thembelihle Tshandapiwa
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/5856 , vital:20982
- Description: Urbanization has resulted in the building of numerous structures such as buildings and roads which reduces the amount of natural land. Urban space planning has taken this into consideration resulting in planned urban green spaces and remnant land within urban areas. Urban green spaces provide a number of ecosystem services which are beneficial to urban residents. This study sought to determine residents’ use and perception of urban green spaces in Bulawayo, the second largest city in Zimbabwe, and to quantify and value four selected ecosystem services, i.e. carbon sequestration by urban trees, urban heat island amelioration, spiritual services and firewood provision. All ecosystem services were valued using local a variety of direct or substitutive methods. Questionnaires were administered at green spaces to green space users to capture responses on reasons why they use green spaces and their perception of green spaces. Residents’ responses showed that they appreciate green spaces as multidimensional spaces which provide a number of benefits for cultural and provisioning services. The role of the green spaces in providing regulating services was not well appreciated by the residents as they did not directly experience these benefits. An association was revealed between primary purpose of visit to urban green spaces and household income. Residents in areas of medium and high density housing visited green spaces on a daily basis, whereas those in more affluent, low density housing areas visited green spaces less often, i.e. a few times a month Carbon sequestration rate was determined by measuring tree diameter within one year to determine increase in carbon sequestered. Bulawayo’s urban green spaces sequester 3 290 t/C/yr valued at approximately $13 000/yr. There was a significant difference in carbon sequestration by urban trees between formal and informal green spaces with formal green spaces sequestering more carbon. Indigenous trees were shown to sequester more carbon than exotic trees and trees with bigger stem diameter were determined sequester more carbon than trees with small diameter. The effect of urban green spaces on ambient temperature was determined by measuring ambient air temperature in green spaces and built up areas over six months. Urban green spaces in Bulawayo play a role in urban micro-climate regulation by reducing the ambient temperature in the green spaces as well as is built up areas. The mean difference between green spaces and surrounding urban areas was up to 60C, with larger green spaces generally showing larger differences. The green spaces extend their cooling effect to surrounding areas thus reducing the temperatures in surrounding residential areas thus reducing the energy demand used for indoor cooling. To determine why residents worship in green spaces, questionnaires were administered to congregation members to capture reasons why and how often they worship in green spaces, challenges faced by the congregants as well as assistance that can be given by the Bulawayo city council to improve the outdoor worship experience. Green spaces offer ideal places for worship in natural areas for congregants to be in touch with nature. The green spaces are also used by some congregations who ordinarily would worship in buildings but fail to do so due to lack of funds for rent or to purchase or construct a church building to use. The value of Bulawayo’s green spaces spiritual services was determined to be $92.50/ha/yr. Firewood provision was also determined by measuring tree diameter within one year to determine increase in fuelwood. The green spaces showed a significant difference in firewood production among sites. Formal green spaces were shown to produce more firewood as compared to informal green spaces and no difference was determined in growth rates between exotic and indigenous tree species. Bulawayo’s green spaces produce 1.9t/ha/yr of firewood with an ecosystem service value of $340 to $490 /ha/yr. These findings indicate the importance of urban green spaces in Bulawayo. They are multifunctional spaces, providing multiple ecosystem services. The local appreciation of the services provided by urban green spaces differs according to the type of service and location in the city. The value of services provided by green spaces is high, albeit not taken into account in planning decisions.
- Full Text:
- Date Issued: 2017
Assessing talent management at Passenger Rail Agency of South Africa (PRASA)
- Authors: Khanyezi, Thembani Hopewell
- Date: 2017
- Subjects: Personnel management Employee retention , Incentives in industry Performance -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/17680 , vital:28429
- Description: There is no question that effective talent management implementation requires a well-defined process. Talent management includes all talent management systems that are required to optimise the workforce within an organisation. The talent management system includes: talent planning, acquiring talent, developing talent, managing talent and retaining talent. Acquired talent should be developed to mould into the organisational culture so that they support the organisational objectives. The research objective of this study was to assess talent management implementation at Metrorail. To achieve this objective a comprehensive study was undertaken on Talent Management. The study involved conducting a literature review to understand the process that is necessary for talent management implementation in an organisation. An empirical study was later conducted to investigate whether the processes of talent management have been successfully implemented at Metrorail. The survey was compared to the literature review to establish whether the findings from Metrorail agreed or disagreed with the literature reviewed. As much as the empirical results showed a case of progress towards Employee Empowerment, Employee Engagement and Talent Retention, there were areas of concern with regard to Recruitment, Compensation and Rewards, Performance Management as well as Organisational Culture.
- Full Text:
- Date Issued: 2017
- Authors: Khanyezi, Thembani Hopewell
- Date: 2017
- Subjects: Personnel management Employee retention , Incentives in industry Performance -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/17680 , vital:28429
- Description: There is no question that effective talent management implementation requires a well-defined process. Talent management includes all talent management systems that are required to optimise the workforce within an organisation. The talent management system includes: talent planning, acquiring talent, developing talent, managing talent and retaining talent. Acquired talent should be developed to mould into the organisational culture so that they support the organisational objectives. The research objective of this study was to assess talent management implementation at Metrorail. To achieve this objective a comprehensive study was undertaken on Talent Management. The study involved conducting a literature review to understand the process that is necessary for talent management implementation in an organisation. An empirical study was later conducted to investigate whether the processes of talent management have been successfully implemented at Metrorail. The survey was compared to the literature review to establish whether the findings from Metrorail agreed or disagreed with the literature reviewed. As much as the empirical results showed a case of progress towards Employee Empowerment, Employee Engagement and Talent Retention, there were areas of concern with regard to Recruitment, Compensation and Rewards, Performance Management as well as Organisational Culture.
- Full Text:
- Date Issued: 2017
Assessing the innovation capability of South African SMEs in pursuing export opportunities
- Authors: Mbele, Lindokuhle Peter
- Date: 2017
- Subjects: New business enterprises -- Management Technological innovations Economic aspects
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/44443 , vital:37811
- Description: Innovation is broadly perceived as an important competitive enabler for any business that needs to survive, stay ahead and prosper. In turbulently and unpredictable global environments, the capability of the organisation to continuously innovate is a key contributor to sustained competitiveness. Innovation capability focuses on making certain that the organisation possess appropriate strategies, structures, culture, leadership techniques and resourcing strategies to bolster effective execution of innovation activities. Innovation can only occur if the organisation has developed innovation capabilities. A number of South African SMEs continue to be reluctant to innovate and trade beyond the borders of their inherent country due to the risks which this involves. SMEs with sound innovation capabilities can make a significant contribution to a nation's competitiveness. Therefore investment in understanding an organisations innovation capabilities and the factors that contribute to successful innovation is necessary. This study assessed the innovation capabilities of South Africa SMEs and their ability to pursue export opportunities. The intention was to gain understanding on how innovation can be used by South African SMEs to improve exports opportunities. The findings revealed that only two thirds of the South African SMEs possess innovative capabilities. The observation was made that some SMEs believe that they are innovative even though they do not have innovative capabilities. Factors that contribute to improved export includes the ability to negotiate export transaction with international partners, the ability to adapt to changing export markets and the ability to meet export demands. These findings present an opportunity for SMEs to continuously assess their innovation capabilities and put measures in place to improve their innovation output and frequency. Globalisation threatens the former safe markets for local businesses, therefore for SMEs to be sustainable, grow and be competitive they should focus on creating innovative products that are marketable globally and continuously seek new markets.
- Full Text:
- Date Issued: 2017
- Authors: Mbele, Lindokuhle Peter
- Date: 2017
- Subjects: New business enterprises -- Management Technological innovations Economic aspects
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/44443 , vital:37811
- Description: Innovation is broadly perceived as an important competitive enabler for any business that needs to survive, stay ahead and prosper. In turbulently and unpredictable global environments, the capability of the organisation to continuously innovate is a key contributor to sustained competitiveness. Innovation capability focuses on making certain that the organisation possess appropriate strategies, structures, culture, leadership techniques and resourcing strategies to bolster effective execution of innovation activities. Innovation can only occur if the organisation has developed innovation capabilities. A number of South African SMEs continue to be reluctant to innovate and trade beyond the borders of their inherent country due to the risks which this involves. SMEs with sound innovation capabilities can make a significant contribution to a nation's competitiveness. Therefore investment in understanding an organisations innovation capabilities and the factors that contribute to successful innovation is necessary. This study assessed the innovation capabilities of South Africa SMEs and their ability to pursue export opportunities. The intention was to gain understanding on how innovation can be used by South African SMEs to improve exports opportunities. The findings revealed that only two thirds of the South African SMEs possess innovative capabilities. The observation was made that some SMEs believe that they are innovative even though they do not have innovative capabilities. Factors that contribute to improved export includes the ability to negotiate export transaction with international partners, the ability to adapt to changing export markets and the ability to meet export demands. These findings present an opportunity for SMEs to continuously assess their innovation capabilities and put measures in place to improve their innovation output and frequency. Globalisation threatens the former safe markets for local businesses, therefore for SMEs to be sustainable, grow and be competitive they should focus on creating innovative products that are marketable globally and continuously seek new markets.
- Full Text:
- Date Issued: 2017
Assessing the organisational maturity level of Rhodes Music Radio with the introduction of social media
- Authors: Gavaza, Mudiwa Artwell
- Date: 2017
- Subjects: Rhodes Music Radio , Rhodes Music Radio -- Marketing , Rhodes Music Radio -- Management , Community radio -- South Africa -- Makhanda , Social media -- Marketing -- South Africa -- Makhanda
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/6269 , vital:21076
- Description: This research seeks to evaluate the organisational maturity of Rhodes Music Radio as it relates to its use of social media. The research takes place within the context of Rhodes Music Radio (RMR) which is a community radio station operating in Grahamstown, South Africa. The station serves the Grahamstown community as a whole, with core listenership coming from the Rhodes University population. RMR has its base on the Rhodes University campus. The contribution of this study is the development of a Social Media Maturity Model which was used to assess the organisational maturity of Rhodes Music Radio with respect to its use of social media. As with other media organisations around the world, social media has become a major factor within the normal operations and functions of RMR. There is much research that has been done about the use of social media as a tool for marketing and branding in business. This tends to be the typical focus of research efforts. Though RMR makes use of social media as a marketing tool, media organisations have gone beyond this one dimensional approach in using social media. Social networking online has become a source of news and trends for organisations within the media space. For an organisation like RMR, social media is used in some way by departments such as Communication, Marketing and Branding, Production, Programming, Music, Technical; together with the presenters and producers who are hosting shows on a daily basis. Bearing the above in mind, this study aims to assess the level of maturity that RMR has as an organisation with use of social media. The goal is to find out how integrated and what systems the station has as a whole to make effective use of social media across the various departments which then helps to make a judgement on the station as a whole. This research has its literature base in the knowledge area of change management and operational excellence. Organisational maturity exists within the broad knowledge area of change management. It provides the theoretical basis upon which to gauge the maturity of RMR in relation to its social media use. Operational excellence provides a basis upon which to judge the quality of RMR’s product which speaks to how well integrated and effective the station is with its use of social media. The method of research was an evaluation that used 2 types of data, making use of both document analysis and interviews as sources of information. This information is then analysed using the Social Media Maturity Model developed specifically for this research from similar organisational maturity models used in other industries such as general management and supply chain management. This model assesses the maturity of the station by first assessing the maturity of the various departments that make up the operations of RMR and then comes up with an aggregate maturity level for the whole organisation. The conclusion of this study is that Rhodes Music Radio is quite mature in terms of its social media use but not yet fully networked. According to the model, the station is described as having a “Community” or “Linked” social media use. On the model, this is Stage 3 out of 5 in terms of maturity. Recommendations given to RMR to further increase this maturity level are for staff members more involved in the social media of the station by following the various RMR accounts and engaging with listeners and other staff members on these platforms. RMR staff need to be trained on the importance of social media and how to use it. The station needs to find a way to convert its social media following into listeners of its broadcast programming. Finally, the station needs to finalise and endorse its Social Media Policy.
- Full Text:
- Date Issued: 2017
- Authors: Gavaza, Mudiwa Artwell
- Date: 2017
- Subjects: Rhodes Music Radio , Rhodes Music Radio -- Marketing , Rhodes Music Radio -- Management , Community radio -- South Africa -- Makhanda , Social media -- Marketing -- South Africa -- Makhanda
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10962/6269 , vital:21076
- Description: This research seeks to evaluate the organisational maturity of Rhodes Music Radio as it relates to its use of social media. The research takes place within the context of Rhodes Music Radio (RMR) which is a community radio station operating in Grahamstown, South Africa. The station serves the Grahamstown community as a whole, with core listenership coming from the Rhodes University population. RMR has its base on the Rhodes University campus. The contribution of this study is the development of a Social Media Maturity Model which was used to assess the organisational maturity of Rhodes Music Radio with respect to its use of social media. As with other media organisations around the world, social media has become a major factor within the normal operations and functions of RMR. There is much research that has been done about the use of social media as a tool for marketing and branding in business. This tends to be the typical focus of research efforts. Though RMR makes use of social media as a marketing tool, media organisations have gone beyond this one dimensional approach in using social media. Social networking online has become a source of news and trends for organisations within the media space. For an organisation like RMR, social media is used in some way by departments such as Communication, Marketing and Branding, Production, Programming, Music, Technical; together with the presenters and producers who are hosting shows on a daily basis. Bearing the above in mind, this study aims to assess the level of maturity that RMR has as an organisation with use of social media. The goal is to find out how integrated and what systems the station has as a whole to make effective use of social media across the various departments which then helps to make a judgement on the station as a whole. This research has its literature base in the knowledge area of change management and operational excellence. Organisational maturity exists within the broad knowledge area of change management. It provides the theoretical basis upon which to gauge the maturity of RMR in relation to its social media use. Operational excellence provides a basis upon which to judge the quality of RMR’s product which speaks to how well integrated and effective the station is with its use of social media. The method of research was an evaluation that used 2 types of data, making use of both document analysis and interviews as sources of information. This information is then analysed using the Social Media Maturity Model developed specifically for this research from similar organisational maturity models used in other industries such as general management and supply chain management. This model assesses the maturity of the station by first assessing the maturity of the various departments that make up the operations of RMR and then comes up with an aggregate maturity level for the whole organisation. The conclusion of this study is that Rhodes Music Radio is quite mature in terms of its social media use but not yet fully networked. According to the model, the station is described as having a “Community” or “Linked” social media use. On the model, this is Stage 3 out of 5 in terms of maturity. Recommendations given to RMR to further increase this maturity level are for staff members more involved in the social media of the station by following the various RMR accounts and engaging with listeners and other staff members on these platforms. RMR staff need to be trained on the importance of social media and how to use it. The station needs to find a way to convert its social media following into listeners of its broadcast programming. Finally, the station needs to finalise and endorse its Social Media Policy.
- Full Text:
- Date Issued: 2017
Assessing the outcomes and consequences of large carnivore reintroductions to the Eastern Cape, South Africa
- Banasiak, Natalia Matgorzata
- Authors: Banasiak, Natalia Matgorzata
- Date: 2017
- Subjects: Carnivores -- Reintroduction , Wildlife reintroduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/11963 , vital:27011
- Description: Reintroduction is a potentially powerful tool available to conservationists to cope with species population declines. Nonetheless, it is poorly understood and past reviews tend to indicate poor results. Reintroduction, under the sensu stricto IUCN definition, must have a primary objective of conservation; however species can be released to sites in their indigenous range (reintroduction sensu lato) to meet other objectives. The outcomes of these reintroductions s.l need to be assessed to determine how effectively they achieve their varied objectives. A Web of Science review revealed that only 32.1% of 131 publications on reintroduction provided clearly defined success criteria. Using economic, ecological, conservation and problem animal management objectives as reintroduction s.l. drivers, I developed context-dependent success definitions for each objective to use in reintroduction outcome assessments. These success criteria were then used to assess the reintroductions s.l. of large carnivores, namely lion, leopard, cheetah, African wild dog, spotted hyaena, and brown hyaena, to 16 private- and state-owned reserves in the Eastern Cape Province, South Africa. Ecotourism and ecological restoration were the most common objectives for the reintroduction of top predators to these reserves. Overall the reintroductions of large carnivores have been successful in meeting their objectives. Only African wild dogs have failed to establish in the province. Causes of objective-specific failures for the other species in some reserves included introductions of same-sex populations, lack of breeding events and changes in reserve management objectives. Assessments for leopard and brown hyaena were inconclusive due to lack of monitoring data. The reintroduction of large carnivores to the Eastern Cape Province has also resulted in the emergence of human-carnivore conflict on neighbouring properties. Carnivores have reportedly escaped from 8 reserves (61.5% of reserves) in the Eastern Cape. A total of 75 conflict events on 68 neighbouring properties (36.7% of neighbouring properties) have been reported. There is a major gap in research around conflict resulting from carnivore reintroductions and future research is required to fully understand the situation in the province in order to develop effective mitigation methods. An adaptive management approach to reintroductions is encouraged to improve monitoring and ensure reintroductions continue to meet their objectives. Furthermore, emerging consequences, such as human-wildlife conflict, and related mitigation strategies should be incorporated into management of reintroduced populations. Communities surrounding reintroduction sites should be educated on lifting baselines where conflict-causing species are recovering to ensure continued success of reintroduction undertakings. National management plans should be developed for all large carnivore species to improve the conservation value of small, fenced reserves that are typical of South African conservation, through a managed metapopulation approach. Management plans should include social, political, and economic factors that can influence the success of reintroductions and ultimate conservation outcomes.
- Full Text:
- Date Issued: 2017
- Authors: Banasiak, Natalia Matgorzata
- Date: 2017
- Subjects: Carnivores -- Reintroduction , Wildlife reintroduction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/11963 , vital:27011
- Description: Reintroduction is a potentially powerful tool available to conservationists to cope with species population declines. Nonetheless, it is poorly understood and past reviews tend to indicate poor results. Reintroduction, under the sensu stricto IUCN definition, must have a primary objective of conservation; however species can be released to sites in their indigenous range (reintroduction sensu lato) to meet other objectives. The outcomes of these reintroductions s.l need to be assessed to determine how effectively they achieve their varied objectives. A Web of Science review revealed that only 32.1% of 131 publications on reintroduction provided clearly defined success criteria. Using economic, ecological, conservation and problem animal management objectives as reintroduction s.l. drivers, I developed context-dependent success definitions for each objective to use in reintroduction outcome assessments. These success criteria were then used to assess the reintroductions s.l. of large carnivores, namely lion, leopard, cheetah, African wild dog, spotted hyaena, and brown hyaena, to 16 private- and state-owned reserves in the Eastern Cape Province, South Africa. Ecotourism and ecological restoration were the most common objectives for the reintroduction of top predators to these reserves. Overall the reintroductions of large carnivores have been successful in meeting their objectives. Only African wild dogs have failed to establish in the province. Causes of objective-specific failures for the other species in some reserves included introductions of same-sex populations, lack of breeding events and changes in reserve management objectives. Assessments for leopard and brown hyaena were inconclusive due to lack of monitoring data. The reintroduction of large carnivores to the Eastern Cape Province has also resulted in the emergence of human-carnivore conflict on neighbouring properties. Carnivores have reportedly escaped from 8 reserves (61.5% of reserves) in the Eastern Cape. A total of 75 conflict events on 68 neighbouring properties (36.7% of neighbouring properties) have been reported. There is a major gap in research around conflict resulting from carnivore reintroductions and future research is required to fully understand the situation in the province in order to develop effective mitigation methods. An adaptive management approach to reintroductions is encouraged to improve monitoring and ensure reintroductions continue to meet their objectives. Furthermore, emerging consequences, such as human-wildlife conflict, and related mitigation strategies should be incorporated into management of reintroduced populations. Communities surrounding reintroduction sites should be educated on lifting baselines where conflict-causing species are recovering to ensure continued success of reintroduction undertakings. National management plans should be developed for all large carnivore species to improve the conservation value of small, fenced reserves that are typical of South African conservation, through a managed metapopulation approach. Management plans should include social, political, and economic factors that can influence the success of reintroductions and ultimate conservation outcomes.
- Full Text:
- Date Issued: 2017
Assessing the physical fitness level of children with intellectual disability in the Grahamstown region of the Eastern Cape, and subsequently designing, implementing and evaluating the efficacy of an exercise intervention
- Authors: Parsons, Samantha Lee
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/19723 , vital:22478
- Description: Background: Extensive research has addressed physical fitness as an agent in promoting health and well-being; however, there is little research on this topic for special populations, such as individuals with intellectual disability and even less relating to the South African context. Children with intellectual disability attending special need schools in disadvantaged communities in the Eastern Cape have lacked the opportunity to participate in structured physical education programs. Implementing a solution to this problem was seen to be a challenge, due to the lack of informative research and available data. Aims: The purpose of this research was two-fold; firstly, it aimed to identify the physical fitness levels of the intellectually disabled children in the Grahamstown region of the Eastern Cape province of South Africa; and secondly, it aimed to implement and evaluate the efficacy of an exercise intervention programme on physical fitness in a local school for children with intellectual disability. Phase 1: The descriptive study compared basic anthropometric as well as physical fitness measures from a sample of participants with intellectual disability (n=29) with a comparable sample of typically developed children (n=25). There were 15 males and 14 females in the intellectually disabled sample group, with an average age of 10.69 ± 1.26 years, and the typically developed sample had 13 males and 12 females, with an average age of 10.51 ± 0.74 years. The anthropometric measures included stature and mass; while the health-related physical fitness components included cardiorespiratory endurance, muscular endurance, strength, body composition, and flexibility; and the skill-related physical fitness components were balance, agility, speed, power, coordination and reaction time. The results revealed that the children with intellectual disability were significantly shorter in stature and lighter in mass (p <0.001) compared to their typically developed peers. Muscular endurance and strength, balance, speed, power, coordination and reaction time were poorer among those with intellectual disabilities (p <0.05). Cardiorespiratory endurance, flexibility and agility were similar between groups. Results of the correlation analyses determined significant (p <0.05) relationships between certain health-related and/or skill-related physical fitness components, which were instrumental for selecting measures for Phase 2. The physical fitness components that had the most significant (p <0.05) correlations were speed with five significant correlations, both muscular endurance and balance with six, coordination with seven, and power with eight significant correlations of the eleven physical fitness components. The comparative results, in conjunction with the correlations, determined that the most suitable physical fitness components to be implemented in the exercise intervention for Phase 2 were muscular endurance, balance, and power. Phase 2: The intervention study was a case-control study (intervention group: n = 16; control group: n = 15), whereby the intervention group was exposed to an 8-week multi-modal exercise intervention training muscular endurance, balance and power. Pre-and post-intervention measures were performed using the same eleven physical fitness tests as in Phase 1. The interaction effects and effect sizes were determined and the results showed significant improvements and large effect sizes for the intervention group’s performance of muscular endurance (p=0.026; d=0.617) and power (p<0.000; d=0.999), whereas no significant changes were found for balance. Furthermore, the exercise intervention also impacted the overall level of physical fitness, as significant changes were found for cardiorespiratory endurance (p<0.001; d=0.98), strength (p=0.021; d=0.654) and flexibility (p=0.032; d=586). In conclusion, the exercise intervention was effective for improving the intellectually disabled participants’ muscular endurance and power but not found effective for balance.
- Full Text:
- Date Issued: 2017
- Authors: Parsons, Samantha Lee
- Date: 2017
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/19723 , vital:22478
- Description: Background: Extensive research has addressed physical fitness as an agent in promoting health and well-being; however, there is little research on this topic for special populations, such as individuals with intellectual disability and even less relating to the South African context. Children with intellectual disability attending special need schools in disadvantaged communities in the Eastern Cape have lacked the opportunity to participate in structured physical education programs. Implementing a solution to this problem was seen to be a challenge, due to the lack of informative research and available data. Aims: The purpose of this research was two-fold; firstly, it aimed to identify the physical fitness levels of the intellectually disabled children in the Grahamstown region of the Eastern Cape province of South Africa; and secondly, it aimed to implement and evaluate the efficacy of an exercise intervention programme on physical fitness in a local school for children with intellectual disability. Phase 1: The descriptive study compared basic anthropometric as well as physical fitness measures from a sample of participants with intellectual disability (n=29) with a comparable sample of typically developed children (n=25). There were 15 males and 14 females in the intellectually disabled sample group, with an average age of 10.69 ± 1.26 years, and the typically developed sample had 13 males and 12 females, with an average age of 10.51 ± 0.74 years. The anthropometric measures included stature and mass; while the health-related physical fitness components included cardiorespiratory endurance, muscular endurance, strength, body composition, and flexibility; and the skill-related physical fitness components were balance, agility, speed, power, coordination and reaction time. The results revealed that the children with intellectual disability were significantly shorter in stature and lighter in mass (p <0.001) compared to their typically developed peers. Muscular endurance and strength, balance, speed, power, coordination and reaction time were poorer among those with intellectual disabilities (p <0.05). Cardiorespiratory endurance, flexibility and agility were similar between groups. Results of the correlation analyses determined significant (p <0.05) relationships between certain health-related and/or skill-related physical fitness components, which were instrumental for selecting measures for Phase 2. The physical fitness components that had the most significant (p <0.05) correlations were speed with five significant correlations, both muscular endurance and balance with six, coordination with seven, and power with eight significant correlations of the eleven physical fitness components. The comparative results, in conjunction with the correlations, determined that the most suitable physical fitness components to be implemented in the exercise intervention for Phase 2 were muscular endurance, balance, and power. Phase 2: The intervention study was a case-control study (intervention group: n = 16; control group: n = 15), whereby the intervention group was exposed to an 8-week multi-modal exercise intervention training muscular endurance, balance and power. Pre-and post-intervention measures were performed using the same eleven physical fitness tests as in Phase 1. The interaction effects and effect sizes were determined and the results showed significant improvements and large effect sizes for the intervention group’s performance of muscular endurance (p=0.026; d=0.617) and power (p<0.000; d=0.999), whereas no significant changes were found for balance. Furthermore, the exercise intervention also impacted the overall level of physical fitness, as significant changes were found for cardiorespiratory endurance (p<0.001; d=0.98), strength (p=0.021; d=0.654) and flexibility (p=0.032; d=586). In conclusion, the exercise intervention was effective for improving the intellectually disabled participants’ muscular endurance and power but not found effective for balance.
- Full Text:
- Date Issued: 2017
Assessing the potential impact of climate change in the south-eastern Great Escarpment, Southern Africa
- Authors: Bentley, Luke Kinross
- Date: 2017
- Subjects: Mountain plants -- Climatic factors -- Drakensberg Mountains , Mountain biodiversity -- Drakensberg Mountains , Climatic changes -- Drakensberg Mountains , Rain and rainfall -- Drakensberg Mountains , Plant diversity -- Climatic factors -- Drakensberg Mountains
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4657 , vital:20709
- Description: Rapid, anthropogenic climate change is a contemporary phenomenon which is threatening natural ecosystems. Mountains are globally important, housing high levels of plant and animal biodiversity, as well as being important suppliers of water with 50% of mountainous regions being essential for the provision of water to downstream inhabitants. Owing to their importance, an assessment of the historical, current and potential impacts of climate change on the south-eastern Great Escarpment encompassing South Africa and Lesotho is necessary and is the primary aim of this thesis. In order to assess the historical and current impacts of climate change, historical rainfall records were collected from 78 sites throughout the Eastern Cape. These records were used to determine rainfall trends and trends in the frequency of daily extreme events. Climate change projections predict increasing trends in summer and annual rainfall, and a marginal increase to a slightly decreasing trend in winter rainfall, depending on if statistically downscaled or dynamically downscaled projections are examined. Extreme events are also predicted to increase in frequency. Results showed trends which generally agree with the predictions, except for extreme events for which there was insufficient data to support the projections. This has implications for farmers in the area and validates the downscaled Regional Climate Models (RCMs) to be used for the predictive analysis determining the potential future impacts of climate change on plant species' distributions in the south-eastern Great Escarpment. In order to assess montane plant species to future climate predictions, occurrence records of 46 species were correlated to rainfall and temperature predictor variables and predictions for species richness and beta diversity were made for current and future climates. This predictive analysis used and compared two correlative species distribution modelling methods - one method used one correlating algorithm in a nuanced manner and the other method used five correlating algorithms in an ensemble. A trend of range restriction to higher elevations for the 46 species analysed was as expected from a warming climate. The nuanced, single algorithm modelling method produced less conservative models. The predicted trend of an elevational increase in montane vegetation in this region points to Lesotho and the Drakensberg highlands as being an important refugium for montane plant taxa of the southeastern Great Escarpment. The Maloti Drakensberg Transfrontier Conservation Area hence needs to be expanded and its mandate properly enforced to protect this region adequately.
- Full Text:
- Date Issued: 2017
- Authors: Bentley, Luke Kinross
- Date: 2017
- Subjects: Mountain plants -- Climatic factors -- Drakensberg Mountains , Mountain biodiversity -- Drakensberg Mountains , Climatic changes -- Drakensberg Mountains , Rain and rainfall -- Drakensberg Mountains , Plant diversity -- Climatic factors -- Drakensberg Mountains
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/4657 , vital:20709
- Description: Rapid, anthropogenic climate change is a contemporary phenomenon which is threatening natural ecosystems. Mountains are globally important, housing high levels of plant and animal biodiversity, as well as being important suppliers of water with 50% of mountainous regions being essential for the provision of water to downstream inhabitants. Owing to their importance, an assessment of the historical, current and potential impacts of climate change on the south-eastern Great Escarpment encompassing South Africa and Lesotho is necessary and is the primary aim of this thesis. In order to assess the historical and current impacts of climate change, historical rainfall records were collected from 78 sites throughout the Eastern Cape. These records were used to determine rainfall trends and trends in the frequency of daily extreme events. Climate change projections predict increasing trends in summer and annual rainfall, and a marginal increase to a slightly decreasing trend in winter rainfall, depending on if statistically downscaled or dynamically downscaled projections are examined. Extreme events are also predicted to increase in frequency. Results showed trends which generally agree with the predictions, except for extreme events for which there was insufficient data to support the projections. This has implications for farmers in the area and validates the downscaled Regional Climate Models (RCMs) to be used for the predictive analysis determining the potential future impacts of climate change on plant species' distributions in the south-eastern Great Escarpment. In order to assess montane plant species to future climate predictions, occurrence records of 46 species were correlated to rainfall and temperature predictor variables and predictions for species richness and beta diversity were made for current and future climates. This predictive analysis used and compared two correlative species distribution modelling methods - one method used one correlating algorithm in a nuanced manner and the other method used five correlating algorithms in an ensemble. A trend of range restriction to higher elevations for the 46 species analysed was as expected from a warming climate. The nuanced, single algorithm modelling method produced less conservative models. The predicted trend of an elevational increase in montane vegetation in this region points to Lesotho and the Drakensberg highlands as being an important refugium for montane plant taxa of the southeastern Great Escarpment. The Maloti Drakensberg Transfrontier Conservation Area hence needs to be expanded and its mandate properly enforced to protect this region adequately.
- Full Text:
- Date Issued: 2017