Expand public works program on infrastructure : lessons from international public works programs 1920'S - 1950'S and 2004-2016
- Authors: Zuma, Siziwe Monica
- Date: 2016
- Subjects: Public works--South Africa Labor--South Africa Job creation--South Africa
- Language: English
- Type: Thesis , Doctoral , Public Administration
- Identifier: http://hdl.handle.net/10353/16102 , vital:40664
- Description: The Expanded Public Works Program on Infrastructure is a national program by the South African Government. It is intending to build and maintain public assets using labour intensive mechanisms. It seeks to offer short term employment and training to the labour participants so that when they exit they may be able to find employment. The program also has an economic sector program of the infrastructure sector called Vuk‘uphile for development of emerging contractors also it is a national program. The Expanded Public Works Program is the government main instrument to job creation in South Africa. Government also seeks to pursue policies that are pro-growth, with the hope that the economic growth will absorbed the unemployed into employment. It is also looking into the small business sector to be the main driver for job creation. Despite this the government‘s commitment, the unemployment rate and poverty rate are increasing and the economy is declining. The study sought to examine if the skills obtained by the participants in the Expanded Public Works Program enable the participants to obtain employment upon exiting the program. It also sought to find any challenges the participants encounter before and after living the program. It sought to look at other international public works programs and theories on public works to learn any lessons. I also sought to study if the program cannot be expanded into for it to create more sustainable employment for the enterprises and the labour participants in order to lengthen the period of work experience skills training, reduce the incidents of poverty and stimulate economic growth. This study followed a literature review methodology, using second source data from various literatures, empirical and non-empirical second source literature. The findings indicate that the skills and the duration of the training are not sufficient for the labour participants to be absorbed by the labour force. The short duration of working in the program is too short to make a meaningful income and work experience that can be sustainable. Upon exiting the program they cannot find employment a large majority of them. The program offered in the Zibambele in KwaZulu Natal offers work on a part time basis for the maintenance of roads over a longer period that acts as a safety net. The program is only in KwaZulu Natal and only on road maintenance; it is not big enough to make a meaningful difference to the amount of unemployment in the country. The Vuk‘uphile program however is offering good skills to the emerging contractor that enables their companies to grow. The international public works programs have been instrumental in creating employment to millions of participants and reduced incidents of poverty. The expanded public works program on infrastructure can be expanded to include asset management, maintenance and can expand to rural infrastructure and development and agricultural infrastructure. The study recommends that the government considers expanding the expanded public works program on infrastructure so that it can provide longer and more sustainable employment to labor participants and entrepreneurs. Also that it considers using the model used to develop emerging contractors in the Vuk‘uphile program to develop small medium businesses in the infrastructure and other areas.
- Full Text:
- Date Issued: 2016
- Authors: Zuma, Siziwe Monica
- Date: 2016
- Subjects: Public works--South Africa Labor--South Africa Job creation--South Africa
- Language: English
- Type: Thesis , Doctoral , Public Administration
- Identifier: http://hdl.handle.net/10353/16102 , vital:40664
- Description: The Expanded Public Works Program on Infrastructure is a national program by the South African Government. It is intending to build and maintain public assets using labour intensive mechanisms. It seeks to offer short term employment and training to the labour participants so that when they exit they may be able to find employment. The program also has an economic sector program of the infrastructure sector called Vuk‘uphile for development of emerging contractors also it is a national program. The Expanded Public Works Program is the government main instrument to job creation in South Africa. Government also seeks to pursue policies that are pro-growth, with the hope that the economic growth will absorbed the unemployed into employment. It is also looking into the small business sector to be the main driver for job creation. Despite this the government‘s commitment, the unemployment rate and poverty rate are increasing and the economy is declining. The study sought to examine if the skills obtained by the participants in the Expanded Public Works Program enable the participants to obtain employment upon exiting the program. It also sought to find any challenges the participants encounter before and after living the program. It sought to look at other international public works programs and theories on public works to learn any lessons. I also sought to study if the program cannot be expanded into for it to create more sustainable employment for the enterprises and the labour participants in order to lengthen the period of work experience skills training, reduce the incidents of poverty and stimulate economic growth. This study followed a literature review methodology, using second source data from various literatures, empirical and non-empirical second source literature. The findings indicate that the skills and the duration of the training are not sufficient for the labour participants to be absorbed by the labour force. The short duration of working in the program is too short to make a meaningful income and work experience that can be sustainable. Upon exiting the program they cannot find employment a large majority of them. The program offered in the Zibambele in KwaZulu Natal offers work on a part time basis for the maintenance of roads over a longer period that acts as a safety net. The program is only in KwaZulu Natal and only on road maintenance; it is not big enough to make a meaningful difference to the amount of unemployment in the country. The Vuk‘uphile program however is offering good skills to the emerging contractor that enables their companies to grow. The international public works programs have been instrumental in creating employment to millions of participants and reduced incidents of poverty. The expanded public works program on infrastructure can be expanded to include asset management, maintenance and can expand to rural infrastructure and development and agricultural infrastructure. The study recommends that the government considers expanding the expanded public works program on infrastructure so that it can provide longer and more sustainable employment to labor participants and entrepreneurs. Also that it considers using the model used to develop emerging contractors in the Vuk‘uphile program to develop small medium businesses in the infrastructure and other areas.
- Full Text:
- Date Issued: 2016
Phototransformation of pollutants using lutetium and zinc phthalocyanines anchored on electrospun polymer fibers
- Authors: Zugle, Ruphino
- Date: 2013
- Subjects: Electrospinning Phthalocyanines Lutetium Zinc Polymers Dysprosium Pollutants Air Pollution Photochemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4286 , http://hdl.handle.net/10962/d1002962
- Description: Novel lanthanide phthalocyanines containing dysprosium, erbium and lutetium as central metals were synthesized using phthalonitrile:metal salt ratio of 4:1 or lower phthalonitrile content as well as using unmetallated phthalocyanine. They were characterized using various spectroscopic and elemental analyses. Dysprosium bis-phthalocyanine was obtained while monomers were obtained for erbium and lutetium phthalocyanines. Theopen-shelldysprosiumbis-phthalocyanine and the monomeric complex of the open-shell erbium were neither fluorescent nor showed the ability to generate singlet oxygen. The triplet states of all the lutetium phthalocyanines were found to be populated with high triplet quantum yields and corresponding high singlet oxygen quantum yields. The fluorescence quantum yields of the lutetium phthalocyanines were however found to be very low. The lutetium phthalocyanines together with unsubstituted zinc phthalocyanine and its derivatives were successfully incorporated into electrospun polymer fibers either by covalent linkage or sorption forces. Spectral characteristics of the functionalized electrospun polymer fibers indicated that the phthalocyanines were bound and their integrity maintained within the fiber matrices. Most importantly the fluorescence and photoactivity of the phthalocyanines were equally maintained within the electrospun fibers. The functionalized electrospun polymer fibers especially those containing the zinc phthalocyanines could qualitatively detect nitrogen dioxide, a known environmental air pollutant. Also all the functionalized electrospun polystyrene and polysulfone fibers containing lutetium and zinc phthalocyanines could be applied for the photoconversion of 4-chlorophenol, 4-nitrophenol and methyl orange. Those of polystyrene could be re-used. Polyacrylic acid and polyurethane functionalized electrospun fibers were found not to be suitable for photocatalytic applications in aqueous medium. 4-Chlorophenol was found to be more susceptible to photodegradation while methyl orange very difficult to degrade.
- Full Text:
- Date Issued: 2013
- Authors: Zugle, Ruphino
- Date: 2013
- Subjects: Electrospinning Phthalocyanines Lutetium Zinc Polymers Dysprosium Pollutants Air Pollution Photochemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4286 , http://hdl.handle.net/10962/d1002962
- Description: Novel lanthanide phthalocyanines containing dysprosium, erbium and lutetium as central metals were synthesized using phthalonitrile:metal salt ratio of 4:1 or lower phthalonitrile content as well as using unmetallated phthalocyanine. They were characterized using various spectroscopic and elemental analyses. Dysprosium bis-phthalocyanine was obtained while monomers were obtained for erbium and lutetium phthalocyanines. Theopen-shelldysprosiumbis-phthalocyanine and the monomeric complex of the open-shell erbium were neither fluorescent nor showed the ability to generate singlet oxygen. The triplet states of all the lutetium phthalocyanines were found to be populated with high triplet quantum yields and corresponding high singlet oxygen quantum yields. The fluorescence quantum yields of the lutetium phthalocyanines were however found to be very low. The lutetium phthalocyanines together with unsubstituted zinc phthalocyanine and its derivatives were successfully incorporated into electrospun polymer fibers either by covalent linkage or sorption forces. Spectral characteristics of the functionalized electrospun polymer fibers indicated that the phthalocyanines were bound and their integrity maintained within the fiber matrices. Most importantly the fluorescence and photoactivity of the phthalocyanines were equally maintained within the electrospun fibers. The functionalized electrospun polymer fibers especially those containing the zinc phthalocyanines could qualitatively detect nitrogen dioxide, a known environmental air pollutant. Also all the functionalized electrospun polystyrene and polysulfone fibers containing lutetium and zinc phthalocyanines could be applied for the photoconversion of 4-chlorophenol, 4-nitrophenol and methyl orange. Those of polystyrene could be re-used. Polyacrylic acid and polyurethane functionalized electrospun fibers were found not to be suitable for photocatalytic applications in aqueous medium. 4-Chlorophenol was found to be more susceptible to photodegradation while methyl orange very difficult to degrade.
- Full Text:
- Date Issued: 2013
Neurocognitive effects of head and body collisions on club level rugby union players
- Authors: Zoccola, Diana
- Date: 2015
- Subjects: Head -- Wounds and injuries -- Psychology , Neuropsychological tests , Head -- Wounds and injuries , Sports injuries -- Psychological aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3257 , http://hdl.handle.net/10962/d1016397
- Description: The objective of the study was to investigate the cumulative neurocognitive effects of repetitive concussive and subconcussive events in club level Rugby Union (hereafter rugby) during the course of one rugby season, in a combined group and individualized case-based approach. Amateur adult club level rugby players (n = 20) were compared with a non-contact control group (n = 22) of equivalent age, years of education and estimated IQ (p = > .05, in all instances), although the two groups were clearly differentiated on the basis of a history of reported concussions (p = < .05). Video analyses documented the tackling maneuvers observed amongst the players during all matches across the rugby season revealing a sobering average of more than a thousand tackles per player, excluding any contact practice sessions. Five rugby players (n = 5) who were observed to have a head jarring event were also isolated for individualized postconcussive follow-up analysis of their neurocognitive profiles. Measures included the ImPACT Verbal and Visual Memory, Visual Motor Speed and Reaction Time composites and the Purdue Pegboard. Independent and dependent statistical analyses were employed to compare the rugby versus control group neurocognitive test profiles at and between the three test intervals. Correlational analyses explored the association between concussion, tackling and neurocognitive test outcomes. Descriptive comparisons of individual neurocognitive test scores with normative data were employed for the case analyses. Taken together, the results implicated vulnerability amongst club rugby players on the motor and speeded tasks, with less robust indications on the memory tasks. While limited in terms of its small sample size, it is considered that the outcome of the study was rendered more robust by virtue of being methodologically multifaceted with heuristic implications for future research studies in the area. The novel inclusion of tackling data as well as fine-tuned case analyses, were of particular relevance in that regard. The results add to a growing body of literature that implicates deleterious neurocognitive effects in participants of a sport such as rugby due to repetitive head jarring incidents that are intrinsic to the game.
- Full Text:
- Date Issued: 2015
- Authors: Zoccola, Diana
- Date: 2015
- Subjects: Head -- Wounds and injuries -- Psychology , Neuropsychological tests , Head -- Wounds and injuries , Sports injuries -- Psychological aspects
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3257 , http://hdl.handle.net/10962/d1016397
- Description: The objective of the study was to investigate the cumulative neurocognitive effects of repetitive concussive and subconcussive events in club level Rugby Union (hereafter rugby) during the course of one rugby season, in a combined group and individualized case-based approach. Amateur adult club level rugby players (n = 20) were compared with a non-contact control group (n = 22) of equivalent age, years of education and estimated IQ (p = > .05, in all instances), although the two groups were clearly differentiated on the basis of a history of reported concussions (p = < .05). Video analyses documented the tackling maneuvers observed amongst the players during all matches across the rugby season revealing a sobering average of more than a thousand tackles per player, excluding any contact practice sessions. Five rugby players (n = 5) who were observed to have a head jarring event were also isolated for individualized postconcussive follow-up analysis of their neurocognitive profiles. Measures included the ImPACT Verbal and Visual Memory, Visual Motor Speed and Reaction Time composites and the Purdue Pegboard. Independent and dependent statistical analyses were employed to compare the rugby versus control group neurocognitive test profiles at and between the three test intervals. Correlational analyses explored the association between concussion, tackling and neurocognitive test outcomes. Descriptive comparisons of individual neurocognitive test scores with normative data were employed for the case analyses. Taken together, the results implicated vulnerability amongst club rugby players on the motor and speeded tasks, with less robust indications on the memory tasks. While limited in terms of its small sample size, it is considered that the outcome of the study was rendered more robust by virtue of being methodologically multifaceted with heuristic implications for future research studies in the area. The novel inclusion of tackling data as well as fine-tuned case analyses, were of particular relevance in that regard. The results add to a growing body of literature that implicates deleterious neurocognitive effects in participants of a sport such as rugby due to repetitive head jarring incidents that are intrinsic to the game.
- Full Text:
- Date Issued: 2015
Travelling shoppers' perceptions on the comprehensive servicescape within the South African retail environment
- Authors: Zinhumwe, Cephas
- Date: 2012
- Subjects: Retail trade -- Customer services -- South Africa , Consumer satisfaction -- South Africa , Consumption (Economics) -- Social aspects , Consumer behavior
- Language: English
- Type: Thesis , Doctoral , DCom
- Identifier: vital:9296 , http://hdl.handle.net/10948/d1013610
- Description: The study is on the influence of comprehensive servicescape on shopping behaviour of road and rail travelling shoppers. The comprehensive servicescape is referred to as synchronization of the multidimensional servicescape dimensions, which are the physical environment, social environment, socially symbolic and the natural dimensions into one entity that the travellers encounter during the shopping exercise. The servicescape cues that include shoppers and the physical set-up of the service firm are important in influencing service quality evaluation and consumer satisfaction. The aim of this study was to establish the impact of servicescape on travelling shoppers’ buying behaviour and shopping motivations amongst different shoppers that were identified within the South African bus and railway stations. The bus and railway station environment induces an interesting type of shopping behaviour amongst the travelers. The purpose of the study was also to explore the travelling shoppers’ expectations and perceptions on the comprehensive servicescape within the bus station’s retail environment. Additionally the study attempted to address important gaps in the South African literature in respect of the influence of socialservicescape on the buyer behaviour and hedonic motivation of travelling shopper. The questionnaires used in the study were constructed along five dimensions of service quality containing statements linked to a five-point Likert-type interval scale anchored by “strongly agree” and “strongly disagree. Self administered questionnaires were used for data collection from the travelling shoppers through “mall intercept technique” and 300 questionnaires were collected from respondents. The academia benefits from this study from the comprehensive servicescape model of the South African bus and railway stations that was developed. The study built on literature by nvestigating the influence of the comprehensive servicescapes as perceived by travelling shoppers within the South African retail environment. Additionally it was shown both theoretically and empirically, that, that service quality in high contact service environment like the bus and railway station can best be explained by an analysis of the comprehensive servicescape or the multidimensional and hierarchical model. As a result of this study retailers will have a full picture on the specific needs, perception and expectations of road and rail travellers in relation to the quality of the stations’ servicescape, which retailers have to improve in order to increase customer patronage. It is assumed that retailers will be aware that store image and the store ambience should meet the challenges of the perceptions, motivations and consumer behaviour of travellers within the comprehensive servicescape of the station. This study provides a trigger effect to spatial planners to design high quality servicescape that will attract travellers for both hedonic and utilitarian shopping. Hirschman and Holbrook (1982) believed that shoppers derive pleasure from the experience of shopping itself, regardless of the joy from acquiring goods, this more so with travelling shoppers. A bus station can be both a growth node and a tourist attraction, if its features are attractive, therefore planners can benefit from this study. In this study theory that forms the bases of the influence of social servicescape on the behaviour of travelling shoppers that frequently visit and participate in shopping at various South African bus station retail outlets is provided. Additionally, this study provided empirical information on the relationships that exist amongst the characteristics of the South African Park Stations’ physical retail environments, user perceptions and interpersonal encounters. The behaviour of shopping travellers was extensively discussed to provide the background of theories and various models concerning shopping behaviour of travellers. Through this work, clarity on consumer behavioural trends of travelling shoppers in the South African retail sector is provided, which assist in differentiating retail products, services and segmentation of markets in a way that could enhance marketing effectiveness amongst the travelling shopping segment. Special attention was paid to factors that motivate road travellers’ choice of stores; the type of products they purchase and their decision making processes. Effort were made to identify, categorize and segment shopper typologies and their shopping behaviours. Effort was also made to discuss extensively the social and physical influences of environments in a retail environment such as that of the bus and railway station. The discussions in this study focussed on describing the comprehensive servicescape model dimensions which shoppers encountered during their shopping activity. The study also indicated the significance of the interaction of service staff with the customers in determining the service quality, customer satisfaction and the future intention of travelers. Additionally this study emphasised the importance of social encounters and perceptiveness to cues within the station, which determine whether they actively or passively are involved in the shopping encounter. The research findings reveal that, travellers perceive the servicescape within the bus station as unattractive and lack appropriate facilities. Furthermore travelers considered the two dimensions (store image and store ambience) of the store’s servicescape as one composite unit of the servicescape. This position is supported in literature, where it is argued that people respond to their environment holistically, rather than to individual stimuli. The travelling shoppers reveal that although they always find the shops from the bus station clean and neat, consumers expect a certain level of ambient environmental conditions to be present. The empirical findings in this study indicate that travelling shoppers are not interested in visiting the stores at the bus and railway station for shopping because merchandise from the bus station stores is poor in quality and unreliable; the surroundings at the station as unpleasant and the bus and railway station stores are congested. Thus, hasty shopping and spending more time or stay longer than planned for shopping at the bus and railway station is not useful to travelling shoppers. Therefore, travellers feel strongly that the shopping environment of the station is not conducive to shopping. These facilities (stations) are only used for travelling purposes; therefore there is a need for improvement in the retail and station facilities in order to increase shopping activities within this servicescape. The research findings reveal that shopping at the bus station seems to be driven by traditional needs such as functional and experiential motivations as well as travelrelated needs such as busstation-atmosphere-related and bus station-infrastructurerelated motivations. It was difficult to deduce a particular typology of shoppers in this environment, but due to the stress related to travelling. Passive shopping was observed amongst travellers, which is not a positive shopping behaviour for retailers.
- Full Text:
- Date Issued: 2012
- Authors: Zinhumwe, Cephas
- Date: 2012
- Subjects: Retail trade -- Customer services -- South Africa , Consumer satisfaction -- South Africa , Consumption (Economics) -- Social aspects , Consumer behavior
- Language: English
- Type: Thesis , Doctoral , DCom
- Identifier: vital:9296 , http://hdl.handle.net/10948/d1013610
- Description: The study is on the influence of comprehensive servicescape on shopping behaviour of road and rail travelling shoppers. The comprehensive servicescape is referred to as synchronization of the multidimensional servicescape dimensions, which are the physical environment, social environment, socially symbolic and the natural dimensions into one entity that the travellers encounter during the shopping exercise. The servicescape cues that include shoppers and the physical set-up of the service firm are important in influencing service quality evaluation and consumer satisfaction. The aim of this study was to establish the impact of servicescape on travelling shoppers’ buying behaviour and shopping motivations amongst different shoppers that were identified within the South African bus and railway stations. The bus and railway station environment induces an interesting type of shopping behaviour amongst the travelers. The purpose of the study was also to explore the travelling shoppers’ expectations and perceptions on the comprehensive servicescape within the bus station’s retail environment. Additionally the study attempted to address important gaps in the South African literature in respect of the influence of socialservicescape on the buyer behaviour and hedonic motivation of travelling shopper. The questionnaires used in the study were constructed along five dimensions of service quality containing statements linked to a five-point Likert-type interval scale anchored by “strongly agree” and “strongly disagree. Self administered questionnaires were used for data collection from the travelling shoppers through “mall intercept technique” and 300 questionnaires were collected from respondents. The academia benefits from this study from the comprehensive servicescape model of the South African bus and railway stations that was developed. The study built on literature by nvestigating the influence of the comprehensive servicescapes as perceived by travelling shoppers within the South African retail environment. Additionally it was shown both theoretically and empirically, that, that service quality in high contact service environment like the bus and railway station can best be explained by an analysis of the comprehensive servicescape or the multidimensional and hierarchical model. As a result of this study retailers will have a full picture on the specific needs, perception and expectations of road and rail travellers in relation to the quality of the stations’ servicescape, which retailers have to improve in order to increase customer patronage. It is assumed that retailers will be aware that store image and the store ambience should meet the challenges of the perceptions, motivations and consumer behaviour of travellers within the comprehensive servicescape of the station. This study provides a trigger effect to spatial planners to design high quality servicescape that will attract travellers for both hedonic and utilitarian shopping. Hirschman and Holbrook (1982) believed that shoppers derive pleasure from the experience of shopping itself, regardless of the joy from acquiring goods, this more so with travelling shoppers. A bus station can be both a growth node and a tourist attraction, if its features are attractive, therefore planners can benefit from this study. In this study theory that forms the bases of the influence of social servicescape on the behaviour of travelling shoppers that frequently visit and participate in shopping at various South African bus station retail outlets is provided. Additionally, this study provided empirical information on the relationships that exist amongst the characteristics of the South African Park Stations’ physical retail environments, user perceptions and interpersonal encounters. The behaviour of shopping travellers was extensively discussed to provide the background of theories and various models concerning shopping behaviour of travellers. Through this work, clarity on consumer behavioural trends of travelling shoppers in the South African retail sector is provided, which assist in differentiating retail products, services and segmentation of markets in a way that could enhance marketing effectiveness amongst the travelling shopping segment. Special attention was paid to factors that motivate road travellers’ choice of stores; the type of products they purchase and their decision making processes. Effort were made to identify, categorize and segment shopper typologies and their shopping behaviours. Effort was also made to discuss extensively the social and physical influences of environments in a retail environment such as that of the bus and railway station. The discussions in this study focussed on describing the comprehensive servicescape model dimensions which shoppers encountered during their shopping activity. The study also indicated the significance of the interaction of service staff with the customers in determining the service quality, customer satisfaction and the future intention of travelers. Additionally this study emphasised the importance of social encounters and perceptiveness to cues within the station, which determine whether they actively or passively are involved in the shopping encounter. The research findings reveal that, travellers perceive the servicescape within the bus station as unattractive and lack appropriate facilities. Furthermore travelers considered the two dimensions (store image and store ambience) of the store’s servicescape as one composite unit of the servicescape. This position is supported in literature, where it is argued that people respond to their environment holistically, rather than to individual stimuli. The travelling shoppers reveal that although they always find the shops from the bus station clean and neat, consumers expect a certain level of ambient environmental conditions to be present. The empirical findings in this study indicate that travelling shoppers are not interested in visiting the stores at the bus and railway station for shopping because merchandise from the bus station stores is poor in quality and unreliable; the surroundings at the station as unpleasant and the bus and railway station stores are congested. Thus, hasty shopping and spending more time or stay longer than planned for shopping at the bus and railway station is not useful to travelling shoppers. Therefore, travellers feel strongly that the shopping environment of the station is not conducive to shopping. These facilities (stations) are only used for travelling purposes; therefore there is a need for improvement in the retail and station facilities in order to increase shopping activities within this servicescape. The research findings reveal that shopping at the bus station seems to be driven by traditional needs such as functional and experiential motivations as well as travelrelated needs such as busstation-atmosphere-related and bus station-infrastructurerelated motivations. It was difficult to deduce a particular typology of shoppers in this environment, but due to the stress related to travelling. Passive shopping was observed amongst travellers, which is not a positive shopping behaviour for retailers.
- Full Text:
- Date Issued: 2012
Synthesis and characterization of binary and ternary palladium alloys for use as alternative counter electrode catalysts in dye sensitized solar cells
- Authors: Zingwe, Nyengerai Hillary
- Date: 2020
- Subjects: Electrocatalysis Chemistry
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: http://hdl.handle.net/10353/18513 , vital:42580
- Description: The dye sensitized solar cell counter electrode facilitates the regeneration of the dye molecules thereby ensuring the provision of higher sunlight to electricity conversion efficiency. The standard platinum electrode suffers from low efficiency due to corrosion by the redox mediator as well as being extremely expensive due to high demand. As an alternative this research study illustrates the efforts undertaken to replace the standard platinum counter electrode with palladium alloy counter electrodes. Application of palladium alloys ensures sustenance of high catalytic activity by palladium which is as effective as platinum. Although palladium is equally as expensive as platinum, its application in the form of alloys minimizes the amount required to produce an effective counter electrode to 0.001-0.004 moles thereby ensuring the provision of high efficiency at a lower cost. Furthermore, charge transfer from the other alloyed elements to the palladium atom increases active sites leading to higher catalytic activity than platinum. Additionally, changes in crystal structure due to alloying enhances resistance to corrosion thus enabling the longevity of the alloy counter electrode in the electrolyte ___________________________________________________________________________ Electrochemical analysis was conducted to determine the catalytic functionality of the developed alloys in cobalt, ferrocene and iodine redox mediators. The binary (PdNi-reduced graphene oxide (rGO) and PdCo-rGO) and ternary (PdNiCo-rGO) palladium alloys were fabricated via a hydrothermal method. In order to determine the composition which could provide the maximum activity, optimization was conducted through variation of the molar ratios of the precursor solutions. The properties of the synthesized palladium alloys were determined using various techniques including x-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The developed alloys were observed to comprise of palladium, nickel, cobalt, and carbon atoms. The particles were spherical in nature for all the unsupported alloys with the carbon supported alloys exhibiting spherical particle wholly surrounded by graphene sheets. Cyclic voltammetry and electrochemical impedance spectroscopy analysis showed that the carbon supported alloys PdNi-rGO, PdCo-rGO and PdNiCo-rGO produced the highest catalytic activities due to the synergy between their respective alloys and the incorporated reduced graphene oxide. The high catalytic effectiveness of these alloys yielded power conversion efficiency in the order PdNiCo-rGO (9.01) > PdNi-rGO (8.4.%) > PdCo-rGO (6.56%) > Pt (5.7%) which were better than the platinum efficiency in the cobalt redox mediator. The higher efficiency in the cobalt redox mediator relative to the iodine electrolyte illustrates that they are viable alternatives to the, corrosive and volatile iodine. Obtained results show that, the high recombination rates between the photogenerated electrons and the oxidized dye molecule which have been reported to reduce power conversion efficiency in one electron redox mediators did not affect the performance of the cell. However, these higher recombination rates affected the ferrocene electrolyte leading to extremely poor efficiency metrics. The obtained results indicated that reduced graphene oxide supported PdNi-rGO, PdNiCo-rGO as well as the unsupported PdNi3 alloys could successfully be implemented as substitutes to the platinum counter electrode in dye sensitized solar cells. The application of the palladium alloys is vital for improving stability and power conversion efficiency, as well as reducing cost.
- Full Text:
- Date Issued: 2020
- Authors: Zingwe, Nyengerai Hillary
- Date: 2020
- Subjects: Electrocatalysis Chemistry
- Language: English
- Type: Thesis , Doctoral , PhD (Chemistry)
- Identifier: http://hdl.handle.net/10353/18513 , vital:42580
- Description: The dye sensitized solar cell counter electrode facilitates the regeneration of the dye molecules thereby ensuring the provision of higher sunlight to electricity conversion efficiency. The standard platinum electrode suffers from low efficiency due to corrosion by the redox mediator as well as being extremely expensive due to high demand. As an alternative this research study illustrates the efforts undertaken to replace the standard platinum counter electrode with palladium alloy counter electrodes. Application of palladium alloys ensures sustenance of high catalytic activity by palladium which is as effective as platinum. Although palladium is equally as expensive as platinum, its application in the form of alloys minimizes the amount required to produce an effective counter electrode to 0.001-0.004 moles thereby ensuring the provision of high efficiency at a lower cost. Furthermore, charge transfer from the other alloyed elements to the palladium atom increases active sites leading to higher catalytic activity than platinum. Additionally, changes in crystal structure due to alloying enhances resistance to corrosion thus enabling the longevity of the alloy counter electrode in the electrolyte ___________________________________________________________________________ Electrochemical analysis was conducted to determine the catalytic functionality of the developed alloys in cobalt, ferrocene and iodine redox mediators. The binary (PdNi-reduced graphene oxide (rGO) and PdCo-rGO) and ternary (PdNiCo-rGO) palladium alloys were fabricated via a hydrothermal method. In order to determine the composition which could provide the maximum activity, optimization was conducted through variation of the molar ratios of the precursor solutions. The properties of the synthesized palladium alloys were determined using various techniques including x-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The developed alloys were observed to comprise of palladium, nickel, cobalt, and carbon atoms. The particles were spherical in nature for all the unsupported alloys with the carbon supported alloys exhibiting spherical particle wholly surrounded by graphene sheets. Cyclic voltammetry and electrochemical impedance spectroscopy analysis showed that the carbon supported alloys PdNi-rGO, PdCo-rGO and PdNiCo-rGO produced the highest catalytic activities due to the synergy between their respective alloys and the incorporated reduced graphene oxide. The high catalytic effectiveness of these alloys yielded power conversion efficiency in the order PdNiCo-rGO (9.01) > PdNi-rGO (8.4.%) > PdCo-rGO (6.56%) > Pt (5.7%) which were better than the platinum efficiency in the cobalt redox mediator. The higher efficiency in the cobalt redox mediator relative to the iodine electrolyte illustrates that they are viable alternatives to the, corrosive and volatile iodine. Obtained results show that, the high recombination rates between the photogenerated electrons and the oxidized dye molecule which have been reported to reduce power conversion efficiency in one electron redox mediators did not affect the performance of the cell. However, these higher recombination rates affected the ferrocene electrolyte leading to extremely poor efficiency metrics. The obtained results indicated that reduced graphene oxide supported PdNi-rGO, PdNiCo-rGO as well as the unsupported PdNi3 alloys could successfully be implemented as substitutes to the platinum counter electrode in dye sensitized solar cells. The application of the palladium alloys is vital for improving stability and power conversion efficiency, as well as reducing cost.
- Full Text:
- Date Issued: 2020
Information and propaganda in the federation of Rhodesia and Nyasaland with special reference to print and radio propaganda for Africans, 1953-1963
- Authors: Zimudzi, Tapiwa Brown
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6957 , vital:21204
- Description: This thesis contributes to the history of the information and propaganda policy and practice of the government of the Federation of Rhodesia and Nyasaland by examining this government's pro-Federation print and radio propaganda for Africans in the Federation. Using a multi-theoretical approach, it analyses the character of this propaganda, highlighting its main methods and themes as well as the policy considerations, plus political and economic circumstances that gave rise to it. It also discusses how Africans in the Federation reacted to this propaganda and assesses its effectiveness in gaining the support of these Africans for Federation and the policies of the Federal government. The thesis argues that Federal government propaganda aimed at gaining the support of Africans for Federation was predominantly panic-driven propaganda and was the product of an information panic that lay at the heart of the very idea of Federation itself. This information panic arose out of the Federal government's belated recognition of the strength of African opposition to Federation and of how this opposition seriously threatened the continued survival of the Federation. It is also argued that this panic-driven pro-Federation propaganda elicited largely hostile reactions from the majority of Africans in the Federation and failed to persuade them to support Federation.
- Full Text:
- Date Issued: 2017
- Authors: Zimudzi, Tapiwa Brown
- Date: 2017
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6957 , vital:21204
- Description: This thesis contributes to the history of the information and propaganda policy and practice of the government of the Federation of Rhodesia and Nyasaland by examining this government's pro-Federation print and radio propaganda for Africans in the Federation. Using a multi-theoretical approach, it analyses the character of this propaganda, highlighting its main methods and themes as well as the policy considerations, plus political and economic circumstances that gave rise to it. It also discusses how Africans in the Federation reacted to this propaganda and assesses its effectiveness in gaining the support of these Africans for Federation and the policies of the Federal government. The thesis argues that Federal government propaganda aimed at gaining the support of Africans for Federation was predominantly panic-driven propaganda and was the product of an information panic that lay at the heart of the very idea of Federation itself. This information panic arose out of the Federal government's belated recognition of the strength of African opposition to Federation and of how this opposition seriously threatened the continued survival of the Federation. It is also argued that this panic-driven pro-Federation propaganda elicited largely hostile reactions from the majority of Africans in the Federation and failed to persuade them to support Federation.
- Full Text:
- Date Issued: 2017
Implementation of strategies used to manage conflict between students and staff in secondary schools in Malawi : towards a comprehensive framework
- Authors: Zimpita, Valentino Tipitana
- Date: 2018
- Subjects: Conflict management Conflict management -- Study and teaching Violence -- Prevention
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9412 , vital:34348
- Description: The study aimed at examining how strategies used to manage conflict between students and staff in secondary schools in Malawi were implemented. This was after it had been noted that conflicts in secondary schools in Malawi usually ended in violence. The study employed a pragmatic research paradigm. In this paradigm, a researcher employs mixed methods approach which collects both quantitative and qualitative data. Using a concurrent triangulation mixed method design, the two types of data were collected concurrently and analysed simultaneously. Study participants were head teachers, teachers, students, education officials and parents. Most of the teachers were randomly sampled while a few other teachers, the head teachers, the education officials and the parents were purposefully sampled. The study found that there were various causes of conflict in secondary schools in Malawi which included misunderstanding of human rights, poor communication between students and staff, poor school management by head teachers and lack of students‘ involvement in decisions that concerned them. The study further found that conflict was in a way beneficial to schools as it was a learning point for both students and staff. However, such benefits were overshadowed by the many evils that violence brought such as disturbing teaching and learning. The study also found that there were two approaches in the way schools managed conflict; engagement of students and calling for police intervention. It transpired that on the overall, stakeholders were aware of different conflict management skills but they did not know how best to use them. In addition, it transpired that stakeholders were not comfortable with win-win approaches to conflict management. This was against a background that the stakeholders were involved in conflict management in different ways. It also came out clear that support to secondary schools in the management of conflict was at two levels; school level and system level. On the part of monitoring, it transpired that the mechanism which were there were ad hoc and they included inspection visits and the requirement that head teachers should always submit reports which could carry issues related to conflict. The study concluded that poorly managed conflicts which turned into violence were a menace to secondary schools in Malawi. In this regard, there was need to ensure effective conflict management in order to avoid violence. To achieve this, the study has made a number of recommendations. Among them, it has been recommended that schools should from time to time take stork of the likely causes of conflict and address them accordingly. It has also been recommended that schools should put in place mechanisms for ensuring two way communication so that students feel free to air out their concerns. At Ministry level, it has been recommended that the MoEST should take guidance and counselling seriously by among other things training teacher councillors and making the post an established one. It has also been recommended that the MoEST should make sure that head teachers, deputy head teachers, teachers, parents and even education officials are inducted in conflict management.
- Full Text:
- Date Issued: 2018
- Authors: Zimpita, Valentino Tipitana
- Date: 2018
- Subjects: Conflict management Conflict management -- Study and teaching Violence -- Prevention
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/9412 , vital:34348
- Description: The study aimed at examining how strategies used to manage conflict between students and staff in secondary schools in Malawi were implemented. This was after it had been noted that conflicts in secondary schools in Malawi usually ended in violence. The study employed a pragmatic research paradigm. In this paradigm, a researcher employs mixed methods approach which collects both quantitative and qualitative data. Using a concurrent triangulation mixed method design, the two types of data were collected concurrently and analysed simultaneously. Study participants were head teachers, teachers, students, education officials and parents. Most of the teachers were randomly sampled while a few other teachers, the head teachers, the education officials and the parents were purposefully sampled. The study found that there were various causes of conflict in secondary schools in Malawi which included misunderstanding of human rights, poor communication between students and staff, poor school management by head teachers and lack of students‘ involvement in decisions that concerned them. The study further found that conflict was in a way beneficial to schools as it was a learning point for both students and staff. However, such benefits were overshadowed by the many evils that violence brought such as disturbing teaching and learning. The study also found that there were two approaches in the way schools managed conflict; engagement of students and calling for police intervention. It transpired that on the overall, stakeholders were aware of different conflict management skills but they did not know how best to use them. In addition, it transpired that stakeholders were not comfortable with win-win approaches to conflict management. This was against a background that the stakeholders were involved in conflict management in different ways. It also came out clear that support to secondary schools in the management of conflict was at two levels; school level and system level. On the part of monitoring, it transpired that the mechanism which were there were ad hoc and they included inspection visits and the requirement that head teachers should always submit reports which could carry issues related to conflict. The study concluded that poorly managed conflicts which turned into violence were a menace to secondary schools in Malawi. In this regard, there was need to ensure effective conflict management in order to avoid violence. To achieve this, the study has made a number of recommendations. Among them, it has been recommended that schools should from time to time take stork of the likely causes of conflict and address them accordingly. It has also been recommended that schools should put in place mechanisms for ensuring two way communication so that students feel free to air out their concerns. At Ministry level, it has been recommended that the MoEST should take guidance and counselling seriously by among other things training teacher councillors and making the post an established one. It has also been recommended that the MoEST should make sure that head teachers, deputy head teachers, teachers, parents and even education officials are inducted in conflict management.
- Full Text:
- Date Issued: 2018
The ecology and control of Opuntia Aurantiaca in South Africa in relation to the cochineal insect, Dactylopius Austrinus
- Authors: Zimmermann, Helmuth G
- Date: 1982
- Subjects: Cochineal insect -- South Africa Cactus -- South Africa Weeds -- Control -- South Africa Insect-plant relationships
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5612 , http://hdl.handle.net/10962/d1003061
- Description: The cochineal insect Dactylopius austrinus De Lotto, which was released on jointed cactus, Opuntia aurantiaca Lindley, in South Africa in 1932, failed to bring the weed under an acceptable level of control in spite of the encouraging results during the first few years after release. The reasons for this apparent failure were never clearly understood. In 1957 the State embarked on an intensive herbicidal control programme which is still in force today. This sustained and expensive programme has undoubtedly reduced the density of the weed in most areas but has failed to solve the problem and the plant continues to expand its range. The biological control of o. aurantiaca in South Africa has been fundamentally influenced by this chemical control campaign. The relationship between chemical and biological control methods is reported in this study.
- Full Text:
- Date Issued: 1982
- Authors: Zimmermann, Helmuth G
- Date: 1982
- Subjects: Cochineal insect -- South Africa Cactus -- South Africa Weeds -- Control -- South Africa Insect-plant relationships
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5612 , http://hdl.handle.net/10962/d1003061
- Description: The cochineal insect Dactylopius austrinus De Lotto, which was released on jointed cactus, Opuntia aurantiaca Lindley, in South Africa in 1932, failed to bring the weed under an acceptable level of control in spite of the encouraging results during the first few years after release. The reasons for this apparent failure were never clearly understood. In 1957 the State embarked on an intensive herbicidal control programme which is still in force today. This sustained and expensive programme has undoubtedly reduced the density of the weed in most areas but has failed to solve the problem and the plant continues to expand its range. The biological control of o. aurantiaca in South Africa has been fundamentally influenced by this chemical control campaign. The relationship between chemical and biological control methods is reported in this study.
- Full Text:
- Date Issued: 1982
The impact of family preservation and family reunification services on families in South Africa: a case study of Amathole District Municipality in the Eastern Cape Province
- Authors: Zimba, Zibonele France
- Date: 2017
- Subjects: Family services Dysfunctional families -- South Africa -- Eastern Cape Family social work -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , Degree
- Identifier: http://hdl.handle.net/10353/3088 , vital:28260
- Description: Families in communities remain vulnerable and, apart from poverty, face a host of other crises and challenges on a daily basis. Amongst the challenges that families face, children are affected most. Services targeting families with very young children therefore are imperative. This study was aimed at exploring the impact of family preservation and family reunification services on families in South Africa, with a focus on the Eastern Cape Province. To answer the research questions of this study, the research adopted a mixed methods design known as methodological triangulation. The study incorporated two sets of participants, Social Workers and heads of families that benefit from family preservation and family reunification services. The total sample for the study included 260 participants; 220 of the participants were heads of families and 40 of the participants were Social Workers. Questionnaires were administered to 200 heads of families and 20 Social Workers selected by means of the random sampling technique. In addition, 20 heads of families and 20 Social Workers who participated in in-depth interviews were purposively selected. The quantitative data were analysed by means of the Statistical Package for the Social Sciences (SPSS) and qualitative data were categorised with the use of themes and subthemes
- Full Text:
- Date Issued: 2017
- Authors: Zimba, Zibonele France
- Date: 2017
- Subjects: Family services Dysfunctional families -- South Africa -- Eastern Cape Family social work -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , Degree
- Identifier: http://hdl.handle.net/10353/3088 , vital:28260
- Description: Families in communities remain vulnerable and, apart from poverty, face a host of other crises and challenges on a daily basis. Amongst the challenges that families face, children are affected most. Services targeting families with very young children therefore are imperative. This study was aimed at exploring the impact of family preservation and family reunification services on families in South Africa, with a focus on the Eastern Cape Province. To answer the research questions of this study, the research adopted a mixed methods design known as methodological triangulation. The study incorporated two sets of participants, Social Workers and heads of families that benefit from family preservation and family reunification services. The total sample for the study included 260 participants; 220 of the participants were heads of families and 40 of the participants were Social Workers. Questionnaires were administered to 200 heads of families and 20 Social Workers selected by means of the random sampling technique. In addition, 20 heads of families and 20 Social Workers who participated in in-depth interviews were purposively selected. The quantitative data were analysed by means of the Statistical Package for the Social Sciences (SPSS) and qualitative data were categorised with the use of themes and subthemes
- Full Text:
- Date Issued: 2017
Decentralised cooperative governance in the South African metropolitan municipalities
- Authors: Zimba, Anthony Andile
- Date: 2012
- Subjects: Community development -- South Africa , Local government -- South Africa , Intergovernmental cooperation -- South Africa , Public administration -- South Africa , Human services -- South Africa , Municipal government -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD (Social Science Dev)
- Identifier: vital:11427 , http://hdl.handle.net/10353/536 , Community development -- South Africa , Local government -- South Africa , Intergovernmental cooperation -- South Africa , Public administration -- South Africa , Human services -- South Africa , Municipal government -- South Africa
- Description: The study emanates from the constitutional imperatives with regard to the role of local government in community development. The notion of cooperative governance is envisaged in the South African Constitution which stipulates that all spheres of government must adhere to the principles of cooperative government and must conduct their activities within the parameters prescribed by the Constitution. The purpose is to support and strengthen the capacity of the local governments to manage their own affairs and to perform their functions. The basic values and principles governing public administration entail that: it must be broadly representative of the people of South Africa in order to redress the imbalances. The existing gaps in the legislation on decision making power at the local level of the municipality, be it in a ward committee or sub council, have not been adequately addressed in the post 1994 democratic dispensation. It is in this context that this study seeks to address these gaps and obstacles, and contribute to the design and development of a decentralized cooperative governance model, specifically to the six metropolitan municipalities and also provide a basis for further research. The findings of the research could be adapted as a national policy in the empowering of municipalities through the dispersal of democratic power which is an essential ingredient of inclusive governance. Based on a case study of six metropolitan municipalities, the research is intended to contribute to the development of empirically grounded; praxis and practical guideline in decentralized cooperative governance which can be adopted and institutionalized in public administration. It is believed that a study of decentralized cooperative governance adds value in that it seeks to link decentralized power and local development. Rather than civil society organisations being seen as adversarial, a creative partnership with the state in local development is crucial. This political assimilation is critical in the construction of democracy through fusing the substantive values of a political culture with the procedural requisites of democratic accountability. This serves to fragment and disperse political power and maintain a system of checks and balances with regard to the exercise of governmental power. The capacity for innovation, flexibility and change can be enhanced at the local level, and it is a cliché that local decision making is viewed as more democratic in contrast to central, top-down decision-making processes. A syncretistic model for local government based on the political adaptation of political and inclusive decentralisation is outlined.
- Full Text:
- Date Issued: 2012
- Authors: Zimba, Anthony Andile
- Date: 2012
- Subjects: Community development -- South Africa , Local government -- South Africa , Intergovernmental cooperation -- South Africa , Public administration -- South Africa , Human services -- South Africa , Municipal government -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD (Social Science Dev)
- Identifier: vital:11427 , http://hdl.handle.net/10353/536 , Community development -- South Africa , Local government -- South Africa , Intergovernmental cooperation -- South Africa , Public administration -- South Africa , Human services -- South Africa , Municipal government -- South Africa
- Description: The study emanates from the constitutional imperatives with regard to the role of local government in community development. The notion of cooperative governance is envisaged in the South African Constitution which stipulates that all spheres of government must adhere to the principles of cooperative government and must conduct their activities within the parameters prescribed by the Constitution. The purpose is to support and strengthen the capacity of the local governments to manage their own affairs and to perform their functions. The basic values and principles governing public administration entail that: it must be broadly representative of the people of South Africa in order to redress the imbalances. The existing gaps in the legislation on decision making power at the local level of the municipality, be it in a ward committee or sub council, have not been adequately addressed in the post 1994 democratic dispensation. It is in this context that this study seeks to address these gaps and obstacles, and contribute to the design and development of a decentralized cooperative governance model, specifically to the six metropolitan municipalities and also provide a basis for further research. The findings of the research could be adapted as a national policy in the empowering of municipalities through the dispersal of democratic power which is an essential ingredient of inclusive governance. Based on a case study of six metropolitan municipalities, the research is intended to contribute to the development of empirically grounded; praxis and practical guideline in decentralized cooperative governance which can be adopted and institutionalized in public administration. It is believed that a study of decentralized cooperative governance adds value in that it seeks to link decentralized power and local development. Rather than civil society organisations being seen as adversarial, a creative partnership with the state in local development is crucial. This political assimilation is critical in the construction of democracy through fusing the substantive values of a political culture with the procedural requisites of democratic accountability. This serves to fragment and disperse political power and maintain a system of checks and balances with regard to the exercise of governmental power. The capacity for innovation, flexibility and change can be enhanced at the local level, and it is a cliché that local decision making is viewed as more democratic in contrast to central, top-down decision-making processes. A syncretistic model for local government based on the political adaptation of political and inclusive decentralisation is outlined.
- Full Text:
- Date Issued: 2012
Women in organisational management in Zimbabwe: theory and practice
- Authors: Zikhali, Whitehead
- Date: 2009
- Subjects: Businesswomen , Discrimination in employment -- Zimbabwe , Women executives -- Zimbabwe , Success in business -- Zimbabwe , Corporate culture -- Zimbabwe , Leadership -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD (Social Science Dev)
- Identifier: vital:11415 , http://hdl.handle.net/10353/d1001185 , Businesswomen , Discrimination in employment -- Zimbabwe , Women executives -- Zimbabwe , Success in business -- Zimbabwe , Corporate culture -- Zimbabwe , Leadership -- Zimbabwe
- Description: The study was premised on the truism that men have historically served in higher echelons of organizational management structures and women are under-represented. The principal objective was to explore the constraints faced by women in accessing higher leadership and senior management positions in public, private and non-governmental organisations in Zimbabwe. This study adopted the triangulation method, that is, qualitative and quantitative approaches. These mixed research methods, were upgraded by the feminist research methodologies, thereby making a contribution in the field of research. The study found out that the constraints that mostly hinder women from accessing leadership and senior management positions in public, private and NGOs were cultural practices, which represent levels of power and control that in turn hinder reforms; and women's socialisation into feminised roles. The study also found out that in most organisations, most females work under male leadership, and this traditional organisational culture, needs to be deconstructed and reversed in order to achieve gender equality. The study recommended for a human centric and integrated organizational management strategy for public, private and NGOs in Zimbabwe. The adoption of a human centric and integrated management approach should aim at gender equity and reduce women's under-representation. A human centred organizational culture has to be practiced, that would create organisational ethos that guide organizational management. An integrated organizational management approach should integrate all systems and processes into one complete framework, enabling people to work as a single unit, unified by organizational goals, shared vision and common values. The system should depend on a balanced mix of the masculine and feminine attributes. The approach should put its weight towards adoption of measures to attract, advance and empower women so as to benefit from their qualifications, experience and talent in a highly competitive environment.
- Full Text:
- Date Issued: 2009
- Authors: Zikhali, Whitehead
- Date: 2009
- Subjects: Businesswomen , Discrimination in employment -- Zimbabwe , Women executives -- Zimbabwe , Success in business -- Zimbabwe , Corporate culture -- Zimbabwe , Leadership -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD (Social Science Dev)
- Identifier: vital:11415 , http://hdl.handle.net/10353/d1001185 , Businesswomen , Discrimination in employment -- Zimbabwe , Women executives -- Zimbabwe , Success in business -- Zimbabwe , Corporate culture -- Zimbabwe , Leadership -- Zimbabwe
- Description: The study was premised on the truism that men have historically served in higher echelons of organizational management structures and women are under-represented. The principal objective was to explore the constraints faced by women in accessing higher leadership and senior management positions in public, private and non-governmental organisations in Zimbabwe. This study adopted the triangulation method, that is, qualitative and quantitative approaches. These mixed research methods, were upgraded by the feminist research methodologies, thereby making a contribution in the field of research. The study found out that the constraints that mostly hinder women from accessing leadership and senior management positions in public, private and NGOs were cultural practices, which represent levels of power and control that in turn hinder reforms; and women's socialisation into feminised roles. The study also found out that in most organisations, most females work under male leadership, and this traditional organisational culture, needs to be deconstructed and reversed in order to achieve gender equality. The study recommended for a human centric and integrated organizational management strategy for public, private and NGOs in Zimbabwe. The adoption of a human centric and integrated management approach should aim at gender equity and reduce women's under-representation. A human centred organizational culture has to be practiced, that would create organisational ethos that guide organizational management. An integrated organizational management approach should integrate all systems and processes into one complete framework, enabling people to work as a single unit, unified by organizational goals, shared vision and common values. The system should depend on a balanced mix of the masculine and feminine attributes. The approach should put its weight towards adoption of measures to attract, advance and empower women so as to benefit from their qualifications, experience and talent in a highly competitive environment.
- Full Text:
- Date Issued: 2009
Family diversity : a South African perspective focusing on Whites in Grahamstown
- Authors: Ziehl, Susan C
- Date: 1998
- Subjects: Families -- History -- Research Families -- South Africa -- Grahamstown Families Families -- Research -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3341 , http://hdl.handle.net/10962/d1004467
- Description: Drawing on developments in the field of family history and studies of families in contemporary settings, the study addresses the question of explaining variations in household patterns. Its empirical basis is a survey of White households in Grahamstown. The surveyed population was broken down in terms of class (occupation) and culture (language) and analyses conducted to determine if there are any statistically significant relationships between these variables and the tendency to reside in particular household structures. The question of 'family ideology' was also addressed as an attempt was made to uncover subjects' views on a variety of family-related issues. On the basis of the research results, a model of the relationship between class, culture and household structure was developed. Its application to a comparison of Black and White household structures in South Africa as well as the United States, is discussed. Finally, attempts at redefining the family are addressed and a new definition of the family proposed.
- Full Text:
- Date Issued: 1998
- Authors: Ziehl, Susan C
- Date: 1998
- Subjects: Families -- History -- Research Families -- South Africa -- Grahamstown Families Families -- Research -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3341 , http://hdl.handle.net/10962/d1004467
- Description: Drawing on developments in the field of family history and studies of families in contemporary settings, the study addresses the question of explaining variations in household patterns. Its empirical basis is a survey of White households in Grahamstown. The surveyed population was broken down in terms of class (occupation) and culture (language) and analyses conducted to determine if there are any statistically significant relationships between these variables and the tendency to reside in particular household structures. The question of 'family ideology' was also addressed as an attempt was made to uncover subjects' views on a variety of family-related issues. On the basis of the research results, a model of the relationship between class, culture and household structure was developed. Its application to a comparison of Black and White household structures in South Africa as well as the United States, is discussed. Finally, attempts at redefining the family are addressed and a new definition of the family proposed.
- Full Text:
- Date Issued: 1998
Teachers' experiences of teacher-led professional development programs :an exploratory study of two clusters in the Mthatha district
- Authors: Zide, Lulama
- Date: 2016
- Subjects: Teachers -- In-service training -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: http://hdl.handle.net/10353/10394 , vital:35444
- Description: Professional growth of teachers is not new, but in recent years, the way in which it is structured and delivered has been reconceptualised. As part of the education reform process, many nations are investing in teacher education as a major engine for driving the changes in the classrooms to ensure learners’ academic success. South Africa is no exclusion to this trend of education reforms, hence, the founding of many professional growth initiatives. Most of these initiatives are aimed at Science and Maths teachers. This was mostly because the majority of Science and Maths teachers in South Africa are considered either under-qualified or not qualified to teach the subject. Yet, despite the efforts and enthusiasm, very little seems to have shifted in the teachers’ practices. Much of the literature still shows that even clusters are not effective in changing the situation completely. Using a qualitative case study design, the researcher explored teachers’ views on their clustering experience, and the benefits such participation and experience brings to their classroom instruction. The major findings of the study show that teachers find clustering as a tool that enriches their teaching, thus, both the content knowledge as well as their pedagogical strategies. The findings also show a consensus of teachers who need the cluster programs done continuously. The researcher concludes that teachers are still not happy with the professional development that is offered to them, and therefore recommends that such programs be offered according to teacher’s need.
- Full Text:
- Date Issued: 2016
- Authors: Zide, Lulama
- Date: 2016
- Subjects: Teachers -- In-service training -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Doctoral , PhD (Education)
- Identifier: http://hdl.handle.net/10353/10394 , vital:35444
- Description: Professional growth of teachers is not new, but in recent years, the way in which it is structured and delivered has been reconceptualised. As part of the education reform process, many nations are investing in teacher education as a major engine for driving the changes in the classrooms to ensure learners’ academic success. South Africa is no exclusion to this trend of education reforms, hence, the founding of many professional growth initiatives. Most of these initiatives are aimed at Science and Maths teachers. This was mostly because the majority of Science and Maths teachers in South Africa are considered either under-qualified or not qualified to teach the subject. Yet, despite the efforts and enthusiasm, very little seems to have shifted in the teachers’ practices. Much of the literature still shows that even clusters are not effective in changing the situation completely. Using a qualitative case study design, the researcher explored teachers’ views on their clustering experience, and the benefits such participation and experience brings to their classroom instruction. The major findings of the study show that teachers find clustering as a tool that enriches their teaching, thus, both the content knowledge as well as their pedagogical strategies. The findings also show a consensus of teachers who need the cluster programs done continuously. The researcher concludes that teachers are still not happy with the professional development that is offered to them, and therefore recommends that such programs be offered according to teacher’s need.
- Full Text:
- Date Issued: 2016
Tourism policy, biodiversity conservation and management: a case study of the Kruger National Park, South Africa
- Authors: Zhou, Leocadia
- Date: 2009
- Subjects: Biodiversity conservation -- South Africa -- Kruger National Park , Ecosystem management -- South Africa -- Kruger National Park , Tourism -- Government policy -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD (Geography)
- Identifier: vital:11513 , http://hdl.handle.net/10353/174 , Biodiversity conservation -- South Africa -- Kruger National Park , Ecosystem management -- South Africa -- Kruger National Park , Tourism -- Government policy -- South Africa
- Description: The Kruger National Park (KNP) management has recently made considerable progress in enacting new policies to address biodiversity conservation and management challenges. However, the interlinkages among the new policies to support biodiversity conservation and management have not been evaluated, particularly the principles and approaches, and how these interact in terms of policy decision-making at the economic and political levels. This study seeks to evaluate the interlinkages among the new policies and how they affect one another, as an avenue to promote a more integrated and comprehensive policy implementation. These policies include the tourism policy, the elephant management policy, and the water provision policy. At policy-making level, the integration of these three policies enhances the possibilities for balancing and controlling the pressures exerted on environmental resources. At the implementation level, it offers a framework for the coordination of the interventions of the policies in space so as to recognise and capitalize on their synergies. Given the inevitably multifarious and departmentalized nature of policy formulation in the KNP, there is a need for the analysis of interlinkages amongst policies. The conceptual framework underpinning this study derives much from Briassoulis’ (2004) policy integration. The research utilizes both qualitative and quantitative research methods, and focuses on selected camp sites within the Park. The findings indicate that current procedures for tourism policy-making and implementation are weak, and little is done by way of impact assessment. This has been attributed to the lack of capacity at the KNP. The findings also reconfirm that policy-making is too fragmented. As a result, policy coordination and cooperation among park managers is weak. This study suggests that an environmental policy integration approach can lead to improved policy-making and implementation. Informed by the data collected from interviews, questionnaires and document analyses, a management framework has been developed to demonstrate how an integrated approach to Environmental Policy Integration (EPI) or management can help sustain the practice of wildlife tourism and support biodiversity conservation. It is concluded that greater realisation of integrated policy-making and implementation in the KNP can be achieved by establishing a formal coordinating office. However, a special feature of KNP policy-making is its widespread consultation system that can provide a fertile ground for enhancing EPI.
- Full Text:
- Date Issued: 2009
- Authors: Zhou, Leocadia
- Date: 2009
- Subjects: Biodiversity conservation -- South Africa -- Kruger National Park , Ecosystem management -- South Africa -- Kruger National Park , Tourism -- Government policy -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD (Geography)
- Identifier: vital:11513 , http://hdl.handle.net/10353/174 , Biodiversity conservation -- South Africa -- Kruger National Park , Ecosystem management -- South Africa -- Kruger National Park , Tourism -- Government policy -- South Africa
- Description: The Kruger National Park (KNP) management has recently made considerable progress in enacting new policies to address biodiversity conservation and management challenges. However, the interlinkages among the new policies to support biodiversity conservation and management have not been evaluated, particularly the principles and approaches, and how these interact in terms of policy decision-making at the economic and political levels. This study seeks to evaluate the interlinkages among the new policies and how they affect one another, as an avenue to promote a more integrated and comprehensive policy implementation. These policies include the tourism policy, the elephant management policy, and the water provision policy. At policy-making level, the integration of these three policies enhances the possibilities for balancing and controlling the pressures exerted on environmental resources. At the implementation level, it offers a framework for the coordination of the interventions of the policies in space so as to recognise and capitalize on their synergies. Given the inevitably multifarious and departmentalized nature of policy formulation in the KNP, there is a need for the analysis of interlinkages amongst policies. The conceptual framework underpinning this study derives much from Briassoulis’ (2004) policy integration. The research utilizes both qualitative and quantitative research methods, and focuses on selected camp sites within the Park. The findings indicate that current procedures for tourism policy-making and implementation are weak, and little is done by way of impact assessment. This has been attributed to the lack of capacity at the KNP. The findings also reconfirm that policy-making is too fragmented. As a result, policy coordination and cooperation among park managers is weak. This study suggests that an environmental policy integration approach can lead to improved policy-making and implementation. Informed by the data collected from interviews, questionnaires and document analyses, a management framework has been developed to demonstrate how an integrated approach to Environmental Policy Integration (EPI) or management can help sustain the practice of wildlife tourism and support biodiversity conservation. It is concluded that greater realisation of integrated policy-making and implementation in the KNP can be achieved by establishing a formal coordinating office. However, a special feature of KNP policy-making is its widespread consultation system that can provide a fertile ground for enhancing EPI.
- Full Text:
- Date Issued: 2009
An adaptive approach for optimized opportunistic routing over Delay Tolerant Mobile Ad hoc Networks
- Authors: Zhao, Xiaogeng
- Date: 2008
- Subjects: Ad hoc networks (Computer networks) Computer network architectures Computer networks Routing protocols (Computer network protocols)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4588 , http://hdl.handle.net/10962/d1004822
- Description: This thesis presents a framework for investigating opportunistic routing in Delay Tolerant Mobile Ad hoc Networks (DTMANETs), and introduces the concept of an Opportunistic Confidence Index (OCI). The OCI enables multiple opportunistic routing protocols to be applied as an adaptive group to improve DTMANET routing reliability, performance, and efficiency. The DTMANET is a recently acknowledged networkarchitecture, which is designed to address the challenging and marginal environments created by adaptive, mobile, and unreliable network node presence. Because of its ad hoc and autonomic nature, routing in a DTMANET is a very challenging problem. The design of routing protocols in such environments, which ensure a high percentage delivery rate (reliability), achieve a reasonable delivery time (performance), and at the same time maintain an acceptable communication overhead (efficiency), is of fundamental consequence to the usefulness of DTMANETs. In recent years, a number of investigations into DTMANET routing have been conducted, resulting in the emergence of a class of routing known as opportunistic routing protocols. Current research into opportunistic routing has exposed opportunities for positive impacts on DTMANET routing. To date, most investigations have concentrated upon one or other of the quality metrics of reliability, performance, or efficiency, while some approaches have pursued a balance of these metrics through assumptions of a high level of global knowledge and/or uniform mobile device behaviours. No prior research that we are aware of has studied the connection between multiple opportunistic elements and their influences upon one another, and none has demonstrated the possibility of modelling and using multiple different opportunistic elements as an adaptive group to aid the routing process in a DTMANET. This thesis investigates OCI opportunities and their viability through the design of an extensible simulation environment, which makes use of methods and techniques such as abstract modelling, opportunistic element simplification and isolation, random attribute generation and assignment, localized knowledge sharing, automated scenario generation, intelligent weight assignment and/or opportunistic element permutation. These methods and techniques are incorporated at both data acquisition and analysis phases. Our results show a significant improvement in all three metric categories. In one of the most applicable scenarios tested, OCI yielded a 31.05% message delivery increase (reliability improvement), 22.18% message delivery time reduction (performance improvement), and 73.64% routing depth decrement (efficiency improvement). We are able to conclude that the OCI approach is feasible across a range of scenarios, and that the use of multiple opportunistic elements to aid decision-making processes in DTMANET environments has value.
- Full Text:
- Date Issued: 2008
- Authors: Zhao, Xiaogeng
- Date: 2008
- Subjects: Ad hoc networks (Computer networks) Computer network architectures Computer networks Routing protocols (Computer network protocols)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4588 , http://hdl.handle.net/10962/d1004822
- Description: This thesis presents a framework for investigating opportunistic routing in Delay Tolerant Mobile Ad hoc Networks (DTMANETs), and introduces the concept of an Opportunistic Confidence Index (OCI). The OCI enables multiple opportunistic routing protocols to be applied as an adaptive group to improve DTMANET routing reliability, performance, and efficiency. The DTMANET is a recently acknowledged networkarchitecture, which is designed to address the challenging and marginal environments created by adaptive, mobile, and unreliable network node presence. Because of its ad hoc and autonomic nature, routing in a DTMANET is a very challenging problem. The design of routing protocols in such environments, which ensure a high percentage delivery rate (reliability), achieve a reasonable delivery time (performance), and at the same time maintain an acceptable communication overhead (efficiency), is of fundamental consequence to the usefulness of DTMANETs. In recent years, a number of investigations into DTMANET routing have been conducted, resulting in the emergence of a class of routing known as opportunistic routing protocols. Current research into opportunistic routing has exposed opportunities for positive impacts on DTMANET routing. To date, most investigations have concentrated upon one or other of the quality metrics of reliability, performance, or efficiency, while some approaches have pursued a balance of these metrics through assumptions of a high level of global knowledge and/or uniform mobile device behaviours. No prior research that we are aware of has studied the connection between multiple opportunistic elements and their influences upon one another, and none has demonstrated the possibility of modelling and using multiple different opportunistic elements as an adaptive group to aid the routing process in a DTMANET. This thesis investigates OCI opportunities and their viability through the design of an extensible simulation environment, which makes use of methods and techniques such as abstract modelling, opportunistic element simplification and isolation, random attribute generation and assignment, localized knowledge sharing, automated scenario generation, intelligent weight assignment and/or opportunistic element permutation. These methods and techniques are incorporated at both data acquisition and analysis phases. Our results show a significant improvement in all three metric categories. In one of the most applicable scenarios tested, OCI yielded a 31.05% message delivery increase (reliability improvement), 22.18% message delivery time reduction (performance improvement), and 73.64% routing depth decrement (efficiency improvement). We are able to conclude that the OCI approach is feasible across a range of scenarios, and that the use of multiple opportunistic elements to aid decision-making processes in DTMANET environments has value.
- Full Text:
- Date Issued: 2008
Removal and recovery of heavy metals from synthetic solutions and electroplating effluents using yeast and the water fern Azolla filiculoides
- Authors: Zhao, Ming
- Date: 1998
- Subjects: Heavy metals -- Environmental aspects Azolla filiculoides -- Biological control Aquatic weeds -- Biological control Yeast Metal ions Yeast fungi -- Biotechnology Cations
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4001 , http://hdl.handle.net/10962/d1004061
- Description: The aims of the project were twofold. The initial objective of the study, based on previous results, was to develop an economically viable methodology for immobilizing yeast cells for the treatment of heavy metal-laden waste water. The non-viable yeast cross-linked by 13% (w/v) formaldehyde/1N HNO₃ exhibited satisfactory mechanical strength and rigidity in a continuous-flow column operation. No apparent disruption of the biomass after repeated use was observed. The cost of immobilizing 1kg dry yeast pellets was estimated at less than US$I. Zn uptake capacity of FA-cross-linked pellets, on batch trials, remained similar to that of raw yeast, reflecting that the immobilizing procedure did not hinder its metal removing capacity. In column studies, cation metals were effectively removed by the yeast pellets from aqueous solution at natural pHs, and then recovered completely by washing the pellets in situ with O.1M HCl. The recovered metals were concentrated in such small volumes that recycling or precipitation of them was facilitated. The metal uptake capacity of the regenerated biomass remained constant in comparison with cycle 1, indicating that reuse of the yeast would be possible. In the case of Cr⁶⁺, a gradual breakthrough curve of Cr in the column profile was noted, with a simultaneous reduction of Cr⁶⁺ to Cr³⁺. However, Cr⁶⁺ in the effluent can be markedly minimised either by accumulation onto the biomass or reduction to its trivalent form. Desorption of bound Cr⁶⁺ with either alkali or salt could not accomplish the regeneration of the biomass. A combination of reduction and desorption with FA/HNO₃ appeared promising in regeneration of the saturated biomass at 4°C. The metal sorption capacities of the yeast pellets, on a batch or a fixed-bed system are relatively lower than that of documented sorbents. Apparently more of the yeast pellets would be required for treating a certain volume of waste effluent, than with other sorbents. Therefore Azolla filiculoides was examined as a suitable sorbent for this purpose. This constitutes the second part of the project. Azolla filiculoides, a naturally-abundant water fern, was screened for its metal sorption and recovering capacities, mechanical stability, flow-permeability and reusability. The azolla biomass appeared to have fulfilled the required mechanical criteria during the repeated sorption-desorption column operations. It is water-insoluble and appears flexible under pressure when rinsed with water. These characters are of crucial importance in a continuous-flow system since a column can be operated at high flow rates without apparent compact of the biomass and pressure loss. Therefore, immobilization of the biomass can be avoided. The sorption isotherm data, obtained from batch removal of Cr⁶⁺, showed that the sorption process was effective, endothermic and highly pH dependent. Considerable amounts of Cr⁶⁺ were accumulated at the optimum pHs of 2-2.5. Column sorption of Cr⁶⁺ at a low flow rate and pH of 2.5 showed optimum performance with a total Cr uptake of 50.4mg/g at 60% saturation of the biomass. Removal of Cr⁶⁺ from an electroplating effluent using an azolla column was deemed reasonably satisfactory, although the uptake declined slightly. Desorption of bound Cr⁶⁺ with various desorbents was incomplete, which resulted in a low regeneration efficiency of about 50%. However, removal and recovery of Cr³⁺ using the azolla column was than that of Cr⁶⁺. Desorption of Cr³⁺ from the spent biomass column was accomplished with the recovery of 80% using O.5N H₂SO₄, The regeneration efficiencies for Cr³⁺ removal were up to 90% and demonstrated that the biomass is reusable. Cation metal uptake capacities of azolla, obtained either from batch or column experiments, are reasonably high in comparison with other sorbents. The uptake of Ni or Zn ions from solution is pH dependent showing the optimum pH of around 6 to 6.5, under the current experimental conditions. The sorption kinetics for cation metals was rapid with about 80% of the bound Ni ions being taken up in the first 10 min. The character of rapid binding is extremely important in a column sorption process, especially on a large scale since it favours an optimum uptake of metals at high flow rates. The Ni or Zn uptakes in column sorption were not markedly affected when the flow rates were increased from 80mllh up to 800ml/h for the 5g biomass used. The cation heavy metals removed from waste effluents were recovered in a concentrated solution of small volume. The desorption of bound Ni and Zn ions from the saturated biomass was accomplished with either O.2N HCl or H₂SO₄ that resulted in recoveries of more than 95%. The metals recovered, in the case of Ni and Zn, are identical to that of plating agents ego nickel sulphate or chloride, so that recycling of the metals is possible. An effluent-free, closed loop of Ni or Zn treatment system was proposed, whereby the Ni or Zn ions can be recycled to the plating bath whilst the purified water is fed back to the rinse tanks. Ca and Mg ions, commonly present in the electroplating effluents, appeared to affect sorption of heavy metals by azolla when metal concentrations were relatively low, presumedly through its competitive binding for the shared sites on surfaces of azolla. The data obtained from column sorption of Ni and Zn follows the BDST model well, enabling the application of the model to predicting design parameters for scale-up of the biosorption column system. It is interesting that the values of metal uptake, expressed in molar quantities, obtained on respective single-metal solutions and the multiple metal system, are similar, implying that the mechanisms involved in the sorption of all metal cations are similar and that the binding sites on surfaces of azolla are probably shared by all cation metals. The surface of the biomass provides sites for metal binding estimated in the range of 0.45-0.57mmol/g, based on the current experiments. The biomass has a surface area of 429 m²/g and water retention of 14.3 ml/g. The functional groups on the surface of azolla were partially identified using chemical modification and metal binding comparison. Among the functional groups examined, carboxyl groups, provided by amino acids and polysaccharides, appeared to play an important role in metal cation binding. The infrared spectra of the samples support this conclusion.
- Full Text:
- Date Issued: 1998
- Authors: Zhao, Ming
- Date: 1998
- Subjects: Heavy metals -- Environmental aspects Azolla filiculoides -- Biological control Aquatic weeds -- Biological control Yeast Metal ions Yeast fungi -- Biotechnology Cations
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4001 , http://hdl.handle.net/10962/d1004061
- Description: The aims of the project were twofold. The initial objective of the study, based on previous results, was to develop an economically viable methodology for immobilizing yeast cells for the treatment of heavy metal-laden waste water. The non-viable yeast cross-linked by 13% (w/v) formaldehyde/1N HNO₃ exhibited satisfactory mechanical strength and rigidity in a continuous-flow column operation. No apparent disruption of the biomass after repeated use was observed. The cost of immobilizing 1kg dry yeast pellets was estimated at less than US$I. Zn uptake capacity of FA-cross-linked pellets, on batch trials, remained similar to that of raw yeast, reflecting that the immobilizing procedure did not hinder its metal removing capacity. In column studies, cation metals were effectively removed by the yeast pellets from aqueous solution at natural pHs, and then recovered completely by washing the pellets in situ with O.1M HCl. The recovered metals were concentrated in such small volumes that recycling or precipitation of them was facilitated. The metal uptake capacity of the regenerated biomass remained constant in comparison with cycle 1, indicating that reuse of the yeast would be possible. In the case of Cr⁶⁺, a gradual breakthrough curve of Cr in the column profile was noted, with a simultaneous reduction of Cr⁶⁺ to Cr³⁺. However, Cr⁶⁺ in the effluent can be markedly minimised either by accumulation onto the biomass or reduction to its trivalent form. Desorption of bound Cr⁶⁺ with either alkali or salt could not accomplish the regeneration of the biomass. A combination of reduction and desorption with FA/HNO₃ appeared promising in regeneration of the saturated biomass at 4°C. The metal sorption capacities of the yeast pellets, on a batch or a fixed-bed system are relatively lower than that of documented sorbents. Apparently more of the yeast pellets would be required for treating a certain volume of waste effluent, than with other sorbents. Therefore Azolla filiculoides was examined as a suitable sorbent for this purpose. This constitutes the second part of the project. Azolla filiculoides, a naturally-abundant water fern, was screened for its metal sorption and recovering capacities, mechanical stability, flow-permeability and reusability. The azolla biomass appeared to have fulfilled the required mechanical criteria during the repeated sorption-desorption column operations. It is water-insoluble and appears flexible under pressure when rinsed with water. These characters are of crucial importance in a continuous-flow system since a column can be operated at high flow rates without apparent compact of the biomass and pressure loss. Therefore, immobilization of the biomass can be avoided. The sorption isotherm data, obtained from batch removal of Cr⁶⁺, showed that the sorption process was effective, endothermic and highly pH dependent. Considerable amounts of Cr⁶⁺ were accumulated at the optimum pHs of 2-2.5. Column sorption of Cr⁶⁺ at a low flow rate and pH of 2.5 showed optimum performance with a total Cr uptake of 50.4mg/g at 60% saturation of the biomass. Removal of Cr⁶⁺ from an electroplating effluent using an azolla column was deemed reasonably satisfactory, although the uptake declined slightly. Desorption of bound Cr⁶⁺ with various desorbents was incomplete, which resulted in a low regeneration efficiency of about 50%. However, removal and recovery of Cr³⁺ using the azolla column was than that of Cr⁶⁺. Desorption of Cr³⁺ from the spent biomass column was accomplished with the recovery of 80% using O.5N H₂SO₄, The regeneration efficiencies for Cr³⁺ removal were up to 90% and demonstrated that the biomass is reusable. Cation metal uptake capacities of azolla, obtained either from batch or column experiments, are reasonably high in comparison with other sorbents. The uptake of Ni or Zn ions from solution is pH dependent showing the optimum pH of around 6 to 6.5, under the current experimental conditions. The sorption kinetics for cation metals was rapid with about 80% of the bound Ni ions being taken up in the first 10 min. The character of rapid binding is extremely important in a column sorption process, especially on a large scale since it favours an optimum uptake of metals at high flow rates. The Ni or Zn uptakes in column sorption were not markedly affected when the flow rates were increased from 80mllh up to 800ml/h for the 5g biomass used. The cation heavy metals removed from waste effluents were recovered in a concentrated solution of small volume. The desorption of bound Ni and Zn ions from the saturated biomass was accomplished with either O.2N HCl or H₂SO₄ that resulted in recoveries of more than 95%. The metals recovered, in the case of Ni and Zn, are identical to that of plating agents ego nickel sulphate or chloride, so that recycling of the metals is possible. An effluent-free, closed loop of Ni or Zn treatment system was proposed, whereby the Ni or Zn ions can be recycled to the plating bath whilst the purified water is fed back to the rinse tanks. Ca and Mg ions, commonly present in the electroplating effluents, appeared to affect sorption of heavy metals by azolla when metal concentrations were relatively low, presumedly through its competitive binding for the shared sites on surfaces of azolla. The data obtained from column sorption of Ni and Zn follows the BDST model well, enabling the application of the model to predicting design parameters for scale-up of the biosorption column system. It is interesting that the values of metal uptake, expressed in molar quantities, obtained on respective single-metal solutions and the multiple metal system, are similar, implying that the mechanisms involved in the sorption of all metal cations are similar and that the binding sites on surfaces of azolla are probably shared by all cation metals. The surface of the biomass provides sites for metal binding estimated in the range of 0.45-0.57mmol/g, based on the current experiments. The biomass has a surface area of 429 m²/g and water retention of 14.3 ml/g. The functional groups on the surface of azolla were partially identified using chemical modification and metal binding comparison. Among the functional groups examined, carboxyl groups, provided by amino acids and polysaccharides, appeared to play an important role in metal cation binding. The infrared spectra of the samples support this conclusion.
- Full Text:
- Date Issued: 1998
Assessing soil carbon and carbon dioxide effluxes under different vegetation cover conditions in the Eastern Cape Province, South Africa
- Authors: Zengeni, Rebecca
- Date: 2013
- Subjects: Soils -- Carbon content -- Measurement , Carbon dioxide mitigation -- South Africa , Greenhouse gas mitigation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10665 , http://hdl.handle.net/10948/d1018676
- Description: Albany thicket is prevalent in the Eastern Cape Province of South Africa. Its spread has diminished through overgrazing and heavy browsing by animals, land clearance and urban expansion. The result is highly degraded land characterized by invasion of alien species. There is a wealth of documented evidence on the high carbon sequestration ability of thicket biome, but not much has been done to assess its effect on carbon dioxide emissions from the soil. Given that the concentration of atmospheric greenhouse gases has been constantly rising since the industrial era, it is imperative to assess the influence of thicket biome as a source or sink of these gases. There is evidence of shifts in the climate in southern Africa as reflected by changes in rainfall patterns, increased temperatures, recurrent droughts and fires. As such, the historical rainfall variability in an Albany thicket region and its interaction with the temporal land use / cover changes was studied. This served to give some background information about the study area for more detailed study on C and carbon dioxide effluxes in thicket vegetation under different levels of degradation. This study thus aimed to determine the influence of thicket vegetation at various levels of degradation on soil carbon and carbon dioxide fluxes. The impact of plant photosynthetic pathway on soil C residence time and gas effluxes were analysed to elucidate on the land-use and cover patterns occurring in the area. All this was done to shed some light on the role of soil and thicket vegetation on carbon dioxide emissions and C storage in the spectrum of a shifting climate. The main area of research was Amakhala reserve in an Albany thicket in Eastern Cape Province; and it concentrated on three land cover types namely intact thicket, degraded thicket and grassland. The objectives mentioned above were achieved by assessing historical rainfall variability from 1970 to 2010 through trend and time series analysis at nine rainfall stations located at Amakhala reserve, Grahamstown, Bathurst, Port Alfred, Uitenhage and Port Elizabeth. The land use changes that have occurred in the Albany thicket region covering Amakhala reserve, Grahamstown, Bathurst and Port Alfred were also assessed for 1989, 1999 and 2009 through satellite image analysis with Idrisi Andes GIS software; then their interaction with rainfall variability were determined. To elucidate on the vegetation species composition and land use / cover changes that have occurred in the study area, plant biomass as well carbon (C) and nitrogen (N) isotope measurements were done. Plant biomass was assessed for the dominant species through use of pre-existing allometric equations that required data on plant basal diameter, canopy area, stem numbers and height. The plant carbon was then estimated through use of a conversion factor of 0.48 on above-ground biomass, while soil organic C was determined through the modified Walkely - Black method. Carbon and N isotope ratios were determined from the foliar material of three replicate samples of dominant plant species then analyzed through mass spectrometry. Soil carbon dioxide effluxes were then monitored in each of the intact thicket (IT), degraded thicket (DT) and grassland (G) over a 10 month period; by measuring the net carbon dioxide exchange rate (NCER) through the dynamic chamber method. An automated carbon dioxide exchange analyzer, coupled to a soil temperature probe and photosynthetic active radiation (PAR) sensor was used; with NCER measurements taken every 20-30 days. Soil temperature, moisture, penetration resistance and PAR readings were taken during each assay and later used to interpret the NCER. Results showed that long term variability in annual rainfall had a declining trend at Grahamstown (r = -0.59), Uitenhage and Bathurst stations (r = -0.32 at both stations), but was not significant at Amakhala, Port Alfred and Port Elizabeth stations. Most reductions in rainfall occurred in the 1980s and 1990s with the autumn, winter and summer rainfalls, the daily rainfall index and the daily rainfall subclasses of 10 mm and above showing a similar trend. The land use change detection gave a significant increase in proportion of degraded and transformed (moderately degraded) land between 1989 and 2009 with most of the increases occurring from 1989 to 1999, while farmland area decreased by 1.8 percent over the years. Thus the Albany region had over 30 percent of its land occupied by transformed vegetation, with heavy browsing and uncontrolled grazing being attributed to the destruction of pristine vegetation. Land-use change to game ranching and goat pastoralism was attributed to the reduction in farmland. Rainfall variability – land use change linkages were most significant in 1999 that recorded the least rainfall and had the lowest mean, maximum and sum of the NDVI. Grahamstown had the most significant rainfall-NDVI trends as it had the lowest NDVIs in 1999 when rainfall was lowest, the highest NDVI in 1989 when rainfall was highest and moderate NDVIs in 2009 when rainfall was moderate. Vegetation at the IT was characterized by a dense thicket with diverse growth forms of canopy trees, woody shrubs, succulent shrubs and ephemerals which mostly had the C3 type of pathway. This was in contrast with the IT soil isotopy that showed more positive C isotope ratios, indicating a switch between C3 and CAM photosynthesis in original vegetation. Most of the canopy trees had disappeared in the DT to be replaced by herbs, shrubs and grasses. As such, there was a huge difference in isotope ratios between DT plants and soils with the plants having mostly C3 metabolism while the soil showed a predominance of CAM plants in previous vegetation, indicating significant changes in land cover. The G site mostly comprised the grasses Themeda triandra and Panicum maximum and a few herbs. It maintained a dominance of C4 metabolism in both plants and soils showing very little change in species composition over the years. Because of the higher species diversity at IT, its soil organic C was quite high reaching levels of 3.4 percent (i.e. 3.4 t C / ha) in the top 10 cm then decreasing with depth (p < 0.001); but was moderate at DT (1.1-1.3 percent) and very low at G ( 0.5 percent C) (p < 0.001). In the same manner above-ground biomass was highest at IT i.e. 330 000 kg/ha; but was only 22 000 kg/ha in DT and as low as 6 700 kg/ha in G vegetation. High biomass at IT was mostly attributed to the succulent shrub Portulacaria afra and the canopy trees Euclea undulate, Rhus longispina and Schotia afra. This above-ground biomass translated to biomass C amounts of 158 000 kg/ha at IT, 10 600 kg/ha at DT and 3 200 kg/ha at G. Thus the IT had the highest while G the least and DT moderate plant and soil C sequestration ability. In all, the conversion of IT to DT led to a net loss of 147 000 Kg of biomass C / ha and 12 000kg less organic C / ha of land. Soil carbon dioxide effluxes were however variable between seasons as they were affected by differences in soil properties and seasonal weather patterns. High soil moisture levels (up to 16 percent gravimetric moisture) resulted in reduced soil penetration resistance (1 to 4 Kg/cm2) which raised effluxes at G and DT sites (up to 1.2 μmols m-2 sec-1) in winter, while low moisture (2 percent) resulted in hard dry soil (14 Kgm-2 penetration resistance) with suppressed CO2 effluxes in spring (0.2 μmols m-2 sec-1) especially in DT and G soils. Rising temperature generally caused accelerated gas emissions but only when moisture was not limiting (as was the case in IT). Thus the high summer temperatures (up to 40oC) gave lower effluxes especially in DT and G (< 1 μm-2sec-1) due to limited moisture supply (< 10 percent); while the Autumn period that had very high temperature (up to 48 oC) and good moisture (up to 16 percent) saw accelerated soil CO2 emissions (averaging 2 μmols m-2 sec-1) from all cover types. The high biomass and litter fall at IT served as ready substrate for soil respiration as long as moisture was not limiting and temperatures were favourable, while reduced cover at DT resulted in poor moisture conservation and creation of hard dry soils in spring and summer with reduced respiration. It was concluded that the DT had high CO2 effluxes in winter and reduced emissions in summer; while the opposite was true for the IT. All the cover types had minimal CO2 effluxes in spring and accelerated emissions in autumn. The grassland on the other hand was a fairly moderate source or sink of CO2 in most seasons compared with the other two covers. It was observed that an environment of good moisture and low-moderate temperatures (such as that in the winter) minimises effluxes while maintaining good plant productivity. It was concluded that thicket vegetation is a good sink of carbon that should be preserved in its natural condition to optimize its carbon sequestration potential. All three land covers served as sources or sinks of CO2 depending on soil and seasonal conditions. Thus high moisture and low penetration resistance generally increased effluxes of thicket ecosystems. The effect of increasing temperature on effluxes was only significant when moisture was not limiting. Conditions of good moisture and low-moderate temperatures gave reasonable amounts of effluxes while maintaining good plant productivity. Though the dry soil conditions significantly reduced effluxes in all land covers; they were not desirable since they decreased plant productivity and ultimately its C sequestration potential. Moreover, prolonged dry conditions only serve to exacerbate recovery of thicket plants as they increase mortality of canopy species in degraded and transformed areas in comparison with intact thicket.
- Full Text:
- Date Issued: 2013
- Authors: Zengeni, Rebecca
- Date: 2013
- Subjects: Soils -- Carbon content -- Measurement , Carbon dioxide mitigation -- South Africa , Greenhouse gas mitigation -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10665 , http://hdl.handle.net/10948/d1018676
- Description: Albany thicket is prevalent in the Eastern Cape Province of South Africa. Its spread has diminished through overgrazing and heavy browsing by animals, land clearance and urban expansion. The result is highly degraded land characterized by invasion of alien species. There is a wealth of documented evidence on the high carbon sequestration ability of thicket biome, but not much has been done to assess its effect on carbon dioxide emissions from the soil. Given that the concentration of atmospheric greenhouse gases has been constantly rising since the industrial era, it is imperative to assess the influence of thicket biome as a source or sink of these gases. There is evidence of shifts in the climate in southern Africa as reflected by changes in rainfall patterns, increased temperatures, recurrent droughts and fires. As such, the historical rainfall variability in an Albany thicket region and its interaction with the temporal land use / cover changes was studied. This served to give some background information about the study area for more detailed study on C and carbon dioxide effluxes in thicket vegetation under different levels of degradation. This study thus aimed to determine the influence of thicket vegetation at various levels of degradation on soil carbon and carbon dioxide fluxes. The impact of plant photosynthetic pathway on soil C residence time and gas effluxes were analysed to elucidate on the land-use and cover patterns occurring in the area. All this was done to shed some light on the role of soil and thicket vegetation on carbon dioxide emissions and C storage in the spectrum of a shifting climate. The main area of research was Amakhala reserve in an Albany thicket in Eastern Cape Province; and it concentrated on three land cover types namely intact thicket, degraded thicket and grassland. The objectives mentioned above were achieved by assessing historical rainfall variability from 1970 to 2010 through trend and time series analysis at nine rainfall stations located at Amakhala reserve, Grahamstown, Bathurst, Port Alfred, Uitenhage and Port Elizabeth. The land use changes that have occurred in the Albany thicket region covering Amakhala reserve, Grahamstown, Bathurst and Port Alfred were also assessed for 1989, 1999 and 2009 through satellite image analysis with Idrisi Andes GIS software; then their interaction with rainfall variability were determined. To elucidate on the vegetation species composition and land use / cover changes that have occurred in the study area, plant biomass as well carbon (C) and nitrogen (N) isotope measurements were done. Plant biomass was assessed for the dominant species through use of pre-existing allometric equations that required data on plant basal diameter, canopy area, stem numbers and height. The plant carbon was then estimated through use of a conversion factor of 0.48 on above-ground biomass, while soil organic C was determined through the modified Walkely - Black method. Carbon and N isotope ratios were determined from the foliar material of three replicate samples of dominant plant species then analyzed through mass spectrometry. Soil carbon dioxide effluxes were then monitored in each of the intact thicket (IT), degraded thicket (DT) and grassland (G) over a 10 month period; by measuring the net carbon dioxide exchange rate (NCER) through the dynamic chamber method. An automated carbon dioxide exchange analyzer, coupled to a soil temperature probe and photosynthetic active radiation (PAR) sensor was used; with NCER measurements taken every 20-30 days. Soil temperature, moisture, penetration resistance and PAR readings were taken during each assay and later used to interpret the NCER. Results showed that long term variability in annual rainfall had a declining trend at Grahamstown (r = -0.59), Uitenhage and Bathurst stations (r = -0.32 at both stations), but was not significant at Amakhala, Port Alfred and Port Elizabeth stations. Most reductions in rainfall occurred in the 1980s and 1990s with the autumn, winter and summer rainfalls, the daily rainfall index and the daily rainfall subclasses of 10 mm and above showing a similar trend. The land use change detection gave a significant increase in proportion of degraded and transformed (moderately degraded) land between 1989 and 2009 with most of the increases occurring from 1989 to 1999, while farmland area decreased by 1.8 percent over the years. Thus the Albany region had over 30 percent of its land occupied by transformed vegetation, with heavy browsing and uncontrolled grazing being attributed to the destruction of pristine vegetation. Land-use change to game ranching and goat pastoralism was attributed to the reduction in farmland. Rainfall variability – land use change linkages were most significant in 1999 that recorded the least rainfall and had the lowest mean, maximum and sum of the NDVI. Grahamstown had the most significant rainfall-NDVI trends as it had the lowest NDVIs in 1999 when rainfall was lowest, the highest NDVI in 1989 when rainfall was highest and moderate NDVIs in 2009 when rainfall was moderate. Vegetation at the IT was characterized by a dense thicket with diverse growth forms of canopy trees, woody shrubs, succulent shrubs and ephemerals which mostly had the C3 type of pathway. This was in contrast with the IT soil isotopy that showed more positive C isotope ratios, indicating a switch between C3 and CAM photosynthesis in original vegetation. Most of the canopy trees had disappeared in the DT to be replaced by herbs, shrubs and grasses. As such, there was a huge difference in isotope ratios between DT plants and soils with the plants having mostly C3 metabolism while the soil showed a predominance of CAM plants in previous vegetation, indicating significant changes in land cover. The G site mostly comprised the grasses Themeda triandra and Panicum maximum and a few herbs. It maintained a dominance of C4 metabolism in both plants and soils showing very little change in species composition over the years. Because of the higher species diversity at IT, its soil organic C was quite high reaching levels of 3.4 percent (i.e. 3.4 t C / ha) in the top 10 cm then decreasing with depth (p < 0.001); but was moderate at DT (1.1-1.3 percent) and very low at G ( 0.5 percent C) (p < 0.001). In the same manner above-ground biomass was highest at IT i.e. 330 000 kg/ha; but was only 22 000 kg/ha in DT and as low as 6 700 kg/ha in G vegetation. High biomass at IT was mostly attributed to the succulent shrub Portulacaria afra and the canopy trees Euclea undulate, Rhus longispina and Schotia afra. This above-ground biomass translated to biomass C amounts of 158 000 kg/ha at IT, 10 600 kg/ha at DT and 3 200 kg/ha at G. Thus the IT had the highest while G the least and DT moderate plant and soil C sequestration ability. In all, the conversion of IT to DT led to a net loss of 147 000 Kg of biomass C / ha and 12 000kg less organic C / ha of land. Soil carbon dioxide effluxes were however variable between seasons as they were affected by differences in soil properties and seasonal weather patterns. High soil moisture levels (up to 16 percent gravimetric moisture) resulted in reduced soil penetration resistance (1 to 4 Kg/cm2) which raised effluxes at G and DT sites (up to 1.2 μmols m-2 sec-1) in winter, while low moisture (2 percent) resulted in hard dry soil (14 Kgm-2 penetration resistance) with suppressed CO2 effluxes in spring (0.2 μmols m-2 sec-1) especially in DT and G soils. Rising temperature generally caused accelerated gas emissions but only when moisture was not limiting (as was the case in IT). Thus the high summer temperatures (up to 40oC) gave lower effluxes especially in DT and G (< 1 μm-2sec-1) due to limited moisture supply (< 10 percent); while the Autumn period that had very high temperature (up to 48 oC) and good moisture (up to 16 percent) saw accelerated soil CO2 emissions (averaging 2 μmols m-2 sec-1) from all cover types. The high biomass and litter fall at IT served as ready substrate for soil respiration as long as moisture was not limiting and temperatures were favourable, while reduced cover at DT resulted in poor moisture conservation and creation of hard dry soils in spring and summer with reduced respiration. It was concluded that the DT had high CO2 effluxes in winter and reduced emissions in summer; while the opposite was true for the IT. All the cover types had minimal CO2 effluxes in spring and accelerated emissions in autumn. The grassland on the other hand was a fairly moderate source or sink of CO2 in most seasons compared with the other two covers. It was observed that an environment of good moisture and low-moderate temperatures (such as that in the winter) minimises effluxes while maintaining good plant productivity. It was concluded that thicket vegetation is a good sink of carbon that should be preserved in its natural condition to optimize its carbon sequestration potential. All three land covers served as sources or sinks of CO2 depending on soil and seasonal conditions. Thus high moisture and low penetration resistance generally increased effluxes of thicket ecosystems. The effect of increasing temperature on effluxes was only significant when moisture was not limiting. Conditions of good moisture and low-moderate temperatures gave reasonable amounts of effluxes while maintaining good plant productivity. Though the dry soil conditions significantly reduced effluxes in all land covers; they were not desirable since they decreased plant productivity and ultimately its C sequestration potential. Moreover, prolonged dry conditions only serve to exacerbate recovery of thicket plants as they increase mortality of canopy species in degraded and transformed areas in comparison with intact thicket.
- Full Text:
- Date Issued: 2013
Examining teachers' role in the promotion of child-friendly environments in Zimbabwean secondary schools : implications for teacher professional development
- Authors: Zendah, Ketiwe
- Date: 2017
- Subjects: Education, Secondary -- Zimbabwe Teachers -- Professional relationships School management and organization -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/4937 , vital:28810
- Description: Hostile school environments are a cause of concern and a perennial international educational problem. The UNICEF’s Child-Friendly Schools (CFS) approach is an international intervention meant to safeguard learners against hostile school environments. The CFS approach mandates schools to offer learners environments and conditions that uphold children’s rights and enhance their development to full potential. The purpose of this mixed methods research study, employing a concurrent triangulation design, was to explore the role of teachers in the promotion of CFS environments. Holsti’s (1970) role theory formed the theoretical framework of this study. The research questions focused on teachers’ understanding of the CFS concept, support offered, strategies employed, challenges encountered, and the implications for teacher professional development. The data collection methods were questionnaires, in-depth interviews, and document analysis with school heads, teachers and learners in the seven government urban secondary schools in Mutare district of Manicaland province in Zimbabwe. Quantitative and qualitative data were independently analysed and merged at the interpretation stage through triangulation of results. Major findings reveal that teachers have poor understanding of the CFS concept, are offered moderate support, occasionally employ viable strategies, and are hindered by various factors in the process of promoting CFS environments. The study’s implications for teacher professional development are rooted in identifying sustainable approaches that adequately equip teachers with relevant information, skills and attitudes that ensure the promotion of CFS environments.
- Full Text:
- Date Issued: 2017
- Authors: Zendah, Ketiwe
- Date: 2017
- Subjects: Education, Secondary -- Zimbabwe Teachers -- Professional relationships School management and organization -- Zimbabwe
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/4937 , vital:28810
- Description: Hostile school environments are a cause of concern and a perennial international educational problem. The UNICEF’s Child-Friendly Schools (CFS) approach is an international intervention meant to safeguard learners against hostile school environments. The CFS approach mandates schools to offer learners environments and conditions that uphold children’s rights and enhance their development to full potential. The purpose of this mixed methods research study, employing a concurrent triangulation design, was to explore the role of teachers in the promotion of CFS environments. Holsti’s (1970) role theory formed the theoretical framework of this study. The research questions focused on teachers’ understanding of the CFS concept, support offered, strategies employed, challenges encountered, and the implications for teacher professional development. The data collection methods were questionnaires, in-depth interviews, and document analysis with school heads, teachers and learners in the seven government urban secondary schools in Mutare district of Manicaland province in Zimbabwe. Quantitative and qualitative data were independently analysed and merged at the interpretation stage through triangulation of results. Major findings reveal that teachers have poor understanding of the CFS concept, are offered moderate support, occasionally employ viable strategies, and are hindered by various factors in the process of promoting CFS environments. The study’s implications for teacher professional development are rooted in identifying sustainable approaches that adequately equip teachers with relevant information, skills and attitudes that ensure the promotion of CFS environments.
- Full Text:
- Date Issued: 2017
The retirement funding adequacy of black South Africans
- Authors: Zeka, Bomikazi
- Date: 2017
- Subjects: Retirement income -- South Africa -- Case studies South Africa -- Finance Finance, Personal
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/13338 , vital:27176
- Description: Despite the importance of retirement planning, many South Africans have been documented as reaching retirement age without adequate retirement funding. A vast amount of research has been conducted on how proper retirement planning can be beneficial for individuals; however, there has been a lack of attention given to researching the retirement planning of black individuals in South Africa. Thus, the primary objective of this study was to identify, investigate and empirically test which factors influence retirement planning, and which aspects of retirement planning influence the retirement funding adequacy of black individuals. After a comprehensive literature review was undertaken on the factors influencing the retirement planning and retirement funding adequacy of individuals, the following independent variables were identified as influencing the mediating variable (Aspects of retirement planning) and the dependent variable (Retirement funding adequacy) in this study: • Financial literacy; • The role of the financial planner; • Family support structure; and • Health status. These independent variables were selected to construct a hypothesised model and research hypotheses, as they have been identified as the prominent factors that influence the retirement planning of black South Africans. Furthermore, these independent variables were used in determining whether they have an influence on the Aspects of retirement planning (incorporating Retirement provisions, Retirement attitudes and Retirement intentions) and, ultimately, improve the Retirement funding adequacy of individuals. In order to establish the influence of the aspects of retirement planning on the retirement funding adequacy of individuals, an empirical investigation was undertaken. A measuring instrument, in the form of a questionnaire, was compiled from secondary literature sources. The respondents were identified though a mixed sampling approach, whereby stratified sampling and convenience sampling were used to attain 441 usable questionnaires that were subjected to statistical analyses. Descriptive statistics, in the form of frequency distributions, were used to summarise Section A and Section B of the measuring instrument. The validity and reliability of the measuring instrument were confirmed by means of exploratory factor analyses (EFA), and Cronbach’s alpha coefficients were also calculated for this purpose. As a result of conducting the EFA, two independent variables (Family support structure and Health status) loaded together, and the factor was renamed accordingly. From the EFA, the independent variables that emerged were The role of the financial planner, Family, health, and financial well-being, and Financial literacy. Furthermore, the EFA revealed that three mediating variables emerged from the mediating variable Aspects of retirement planning. These three mediating variables were consequently named Retirement intentions, Retirement attitudes, and Retirement provisions. There were no eliminated variables in this study. Based on the results of the EFA, some of the definitions of the variables were adapted. Consequently, the hypothesised model and its research hypotheses were adapted to reflect the results of the EFA. The results of the Cronbach’s alphas calculated reported that all the measuring scales used in the questionnaire of the study were reliable. Furthermore, descriptive statistics were also calculated to summarise the sample data, and Pearson’s product moment correlations were calculated to establish the correlations between all the variables used in this study. A multiple regression analysis was used to investigate the influence of the various independent variables on the mediating variables and the dependent variable. Furthermore, structural equation modelling (SEM) was used as the main statistical procedure to test for mediation in the study. SEM was also used to assess and confirm the results of the multiple regression analyses. Based on the results of the multiple regression analyses and SEM, the hypothesised relationships of the study were accepted or rejected. Additionally, the results of SEM revealed that the revised model of the study displayed acceptable model fit. To conclude the empirical investigation, t-tests and an analysis of variance (ANOVA) tests were performed to assess whether the respondents’ perceptions of the variables used in the study differed as a result of the respondents’ demographic information. Furthermore, to establish significant differences between individual mean scores, post-hoc Tukey tests were calculated, and practical significance was assessed by calculating Cohen’s d values. The main empirical results of the study found that statistically significant relationships exist between the independent variables The role of the financial planner and Family, health, and financial well-being, and the mediating variable Retirement intentions. Furthermore, a significant relationship was found between the independent variable Financial literacy and the mediating variable Retirement attitudes. Other significant relationships were present between all the independent variables The role of the financial planner, Family, health, and financial well-being and Financial literacy, and the mediating variable Retirement provisions. The study also established statistically significant relationships between the mediating variables Retirement attitudes and Retirement provisions and the dependent variable Retirement funding adequacy. Statistically significant relationships were also present between the independent variables Family, health, and financial well-being and Financial literacy and the dependent variable Retirement funding adequacy. This study has added to the limited amount of academic literature in the field of retirement planning in South Africa. Through the hypothesised model developed in this study, a significant contribution has been made towards investigating the factors that influence the retirement planning and retirement funding adequacy of black individuals residing in South Africa. This study presents recommendations to black individuals on practical strategies that could help to improve their retirement planning and retirement funding adequacy. Furthermore, suggestions are presented to financial planners and financial institutions, in order to assist black individuals or potential clients to improve their retirement planning and to help ensure that individuals are financially independent when they reach retirement age. It is recommended that financial institutions provide financial products/services that will cater to black South Africans.
- Full Text:
- Date Issued: 2017
- Authors: Zeka, Bomikazi
- Date: 2017
- Subjects: Retirement income -- South Africa -- Case studies South Africa -- Finance Finance, Personal
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/13338 , vital:27176
- Description: Despite the importance of retirement planning, many South Africans have been documented as reaching retirement age without adequate retirement funding. A vast amount of research has been conducted on how proper retirement planning can be beneficial for individuals; however, there has been a lack of attention given to researching the retirement planning of black individuals in South Africa. Thus, the primary objective of this study was to identify, investigate and empirically test which factors influence retirement planning, and which aspects of retirement planning influence the retirement funding adequacy of black individuals. After a comprehensive literature review was undertaken on the factors influencing the retirement planning and retirement funding adequacy of individuals, the following independent variables were identified as influencing the mediating variable (Aspects of retirement planning) and the dependent variable (Retirement funding adequacy) in this study: • Financial literacy; • The role of the financial planner; • Family support structure; and • Health status. These independent variables were selected to construct a hypothesised model and research hypotheses, as they have been identified as the prominent factors that influence the retirement planning of black South Africans. Furthermore, these independent variables were used in determining whether they have an influence on the Aspects of retirement planning (incorporating Retirement provisions, Retirement attitudes and Retirement intentions) and, ultimately, improve the Retirement funding adequacy of individuals. In order to establish the influence of the aspects of retirement planning on the retirement funding adequacy of individuals, an empirical investigation was undertaken. A measuring instrument, in the form of a questionnaire, was compiled from secondary literature sources. The respondents were identified though a mixed sampling approach, whereby stratified sampling and convenience sampling were used to attain 441 usable questionnaires that were subjected to statistical analyses. Descriptive statistics, in the form of frequency distributions, were used to summarise Section A and Section B of the measuring instrument. The validity and reliability of the measuring instrument were confirmed by means of exploratory factor analyses (EFA), and Cronbach’s alpha coefficients were also calculated for this purpose. As a result of conducting the EFA, two independent variables (Family support structure and Health status) loaded together, and the factor was renamed accordingly. From the EFA, the independent variables that emerged were The role of the financial planner, Family, health, and financial well-being, and Financial literacy. Furthermore, the EFA revealed that three mediating variables emerged from the mediating variable Aspects of retirement planning. These three mediating variables were consequently named Retirement intentions, Retirement attitudes, and Retirement provisions. There were no eliminated variables in this study. Based on the results of the EFA, some of the definitions of the variables were adapted. Consequently, the hypothesised model and its research hypotheses were adapted to reflect the results of the EFA. The results of the Cronbach’s alphas calculated reported that all the measuring scales used in the questionnaire of the study were reliable. Furthermore, descriptive statistics were also calculated to summarise the sample data, and Pearson’s product moment correlations were calculated to establish the correlations between all the variables used in this study. A multiple regression analysis was used to investigate the influence of the various independent variables on the mediating variables and the dependent variable. Furthermore, structural equation modelling (SEM) was used as the main statistical procedure to test for mediation in the study. SEM was also used to assess and confirm the results of the multiple regression analyses. Based on the results of the multiple regression analyses and SEM, the hypothesised relationships of the study were accepted or rejected. Additionally, the results of SEM revealed that the revised model of the study displayed acceptable model fit. To conclude the empirical investigation, t-tests and an analysis of variance (ANOVA) tests were performed to assess whether the respondents’ perceptions of the variables used in the study differed as a result of the respondents’ demographic information. Furthermore, to establish significant differences between individual mean scores, post-hoc Tukey tests were calculated, and practical significance was assessed by calculating Cohen’s d values. The main empirical results of the study found that statistically significant relationships exist between the independent variables The role of the financial planner and Family, health, and financial well-being, and the mediating variable Retirement intentions. Furthermore, a significant relationship was found between the independent variable Financial literacy and the mediating variable Retirement attitudes. Other significant relationships were present between all the independent variables The role of the financial planner, Family, health, and financial well-being and Financial literacy, and the mediating variable Retirement provisions. The study also established statistically significant relationships between the mediating variables Retirement attitudes and Retirement provisions and the dependent variable Retirement funding adequacy. Statistically significant relationships were also present between the independent variables Family, health, and financial well-being and Financial literacy and the dependent variable Retirement funding adequacy. This study has added to the limited amount of academic literature in the field of retirement planning in South Africa. Through the hypothesised model developed in this study, a significant contribution has been made towards investigating the factors that influence the retirement planning and retirement funding adequacy of black individuals residing in South Africa. This study presents recommendations to black individuals on practical strategies that could help to improve their retirement planning and retirement funding adequacy. Furthermore, suggestions are presented to financial planners and financial institutions, in order to assist black individuals or potential clients to improve their retirement planning and to help ensure that individuals are financially independent when they reach retirement age. It is recommended that financial institutions provide financial products/services that will cater to black South Africans.
- Full Text:
- Date Issued: 2017
Benchmark value chain clusters, agglomeration economies and dynamic externalities : an intergrated approach to regional economic development
- Authors: Zeelie, Eben Johannes
- Date: 2009
- Subjects: Industrial clusters , Regional economics , Regional economic disparities , Economic development , Regional planning
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8594 , http://hdl.handle.net/10948/1086 , Industrial clusters , Regional economics , Regional economic disparities , Economic development , Regional planning
- Description: From the broad overview of the cluster literature, the proposition emerges that the manipulation of regional economic structural and cluster factor conditions within a geographically proximate region can translate into sustainable regional economic growth outcomes. As a first step in exploring this research, a theoretical framework for the conceptualisation of industry clusters was established and a methodological framework applied to statistically identify major manufacturing value chain clusters in the Eastern Cape Province. This methodology combines a strength-of-linkage measure for all pairs of supply and use sectors (as revealed in the systematic analysis of intermediate purchasing and sales patterns in the South African Final Supply and Use Tables: 2002) with the application of Ward’s hierarchical cluster algorithm to map the national benchmark value chain clusters in the South African national economy. The ensuing national value chain benchmark cluster framework was then transposed to the Eastern Cape Province to reveal cluster concentrations and gaps that exist in the value chain clusters in the province. The methodology applied in this study provides an objective and clear perspective of inter-industry linkages in the South African economy and produces more detailed and evenly distributed clusters than traditional cluster identification methodologies. Secondary linkages were determined for each of the twenty-six core value chain clusters to depict the diversity of sectors linked to the respective core clusters. In transposing the national benchmark value chain cluster framework onto the Eastern Cape Province economy, a number of distinct advantages emerge. Firstly, it reveals gaps in value chain cluster groupings that may be filled through industry recruiting or regional business development strategies. However, not all industries absent from value chain clusters in the region are equally attractive for recruitment. Henceforth, the number of direct and indirect linkages to industries absent from the Eastern Cape Province serves as a measure of their relative attractiveness when considering their recruitment into the region. vi The benchmark value chain cluster framework alone does not explain which agglomeration externalities are generated and exploited within each cluster, but it served as the overarching framework for the remainder of the research. Accordingly, the value chain cluster framework was applied to evidence whether specialisation, competition or diversity (represented by MAR, Porter and Jacobs economies respectively) is the operative mechanism in generating cluster growth in the Eastern Cape Province. Since agglomeration externalities are not directly observable, construct-valid indicators for the various externalities, as well as appropriate mechanisms to empirically assess the statistical relevance of MAR-, Porter and Jacobs economies in stimulating cluster growth, were established. This thesis added to agglomeration literature by disaggregating the standard measure of diversity externalities into two unique diversity indicators, namely supply diversity (SDiv) and use diversity (UDiv). The SDiv- and UDiv coefficients measure the degree to which a value chain cluster’s supplying/user sectoral mix at provincial level differs from that of the cluster grouping at the national level. This distinction between supply-and use diversity developed in this study firstly provides a clearer insight into the relative regional presence of supplying- and using sectors to the various value chain clusters, and secondly, serves as a useful mechanism to regional policymakers in identifying industries that may be targeted for investment into a region. Therefore, by separating the diversity into its two components, a clear distinction can be drawn between the impact of supplying- and using sectors on value chain cluster growth in a particular region. From a narrow perspective, the empirical findings validate both the Marshall Arrow Romer- (small positive impact of regional cluster concentration) and the Jacobs theory (significant positive impact of cluster supply- and use diversity on cluster growth), while it invalidates Porter’s theory (no correlation between competition and cluster performance). The positive effect size recorded between the level of value chain cluster concentration and differential growth indicates that policy makers in the Eastern Cape Province will be well advised to direct growth interventions towards larger concentrated clusters, than towards smaller, incipient value chain clusters. Additionally, vii the effectiveness of targeted inward FDI to the Eastern Cape Province may be raised by evaluating the economic impact against current value chain cluster structure, as well as the effect on the supply- and use diversities of existing value chain clusters in the province. This thesis has also illustrated that value chain clusters that are concentrated in the region, show a positive effect size with the level of supply diversity in the region. Conversely, value chain clusters that reflect high levels of competitiveness record a positive effect size with use diversity. Policy interventions aimed at raising the performance of value chain clusters typified by smaller players in a competitive environment, should therefore consider raising the respective levels of use diversity in the region. This research awakens the proposition that a reliance on a serendipitous approach to generate dynamic externalities is not sufficient, and that certain factor conditions favour the transfer of tacit knowledge between cluster members. Accordingly, this research empirically explored whether statistically significant relationships can be detected between the common cluster elements, or factor conditions, that serve as conduits for the transfer of dynamic externalities and value chain cluster growth in the Eastern Cape Province. The findings indicate that linkages with knowledge generating institutions in the Eastern Cape Province do, albeit to a relatively small extent, have an impact on value chain cluster growth, and validates the assertion that cognitive enhancing institutions contribute to cluster growth. The importance of backward and forward linkages in nurturing regional growth is signified by the moderate effect size recorded by the level of vertical linkages and total value chain cluster growth. Similarly, a moderate effect size was recorded between the level of horizontal linkages and value chain cluster growth, which shows that cooperation amongst competing firms do stimulate cluster and regional growth in the Eastern Cape Province and affirms the proposition that inter-firm linkages on both vertical- and horizontal levels stimulate cluster growth. An expectation was that the institutional framework conditions would have a significant impact on value chain cluster growth in the Eastern Cape Province. However, the empirical findings reflect that the institutional framework conditions have no statistical impact on value chain cluster growth. The study also found a moderate, positive effect size between value chain cluster size (number of employees) and growth, which shows viii that size matters in regional growth. In other words, in contrast to their European counterparts, the larger the number of employees per value chain cluster, the greater the impact on value chain cluster growth in the Eastern Cape Province.
- Full Text:
- Date Issued: 2009
- Authors: Zeelie, Eben Johannes
- Date: 2009
- Subjects: Industrial clusters , Regional economics , Regional economic disparities , Economic development , Regional planning
- Language: English
- Type: Thesis , Doctoral , DBA
- Identifier: vital:8594 , http://hdl.handle.net/10948/1086 , Industrial clusters , Regional economics , Regional economic disparities , Economic development , Regional planning
- Description: From the broad overview of the cluster literature, the proposition emerges that the manipulation of regional economic structural and cluster factor conditions within a geographically proximate region can translate into sustainable regional economic growth outcomes. As a first step in exploring this research, a theoretical framework for the conceptualisation of industry clusters was established and a methodological framework applied to statistically identify major manufacturing value chain clusters in the Eastern Cape Province. This methodology combines a strength-of-linkage measure for all pairs of supply and use sectors (as revealed in the systematic analysis of intermediate purchasing and sales patterns in the South African Final Supply and Use Tables: 2002) with the application of Ward’s hierarchical cluster algorithm to map the national benchmark value chain clusters in the South African national economy. The ensuing national value chain benchmark cluster framework was then transposed to the Eastern Cape Province to reveal cluster concentrations and gaps that exist in the value chain clusters in the province. The methodology applied in this study provides an objective and clear perspective of inter-industry linkages in the South African economy and produces more detailed and evenly distributed clusters than traditional cluster identification methodologies. Secondary linkages were determined for each of the twenty-six core value chain clusters to depict the diversity of sectors linked to the respective core clusters. In transposing the national benchmark value chain cluster framework onto the Eastern Cape Province economy, a number of distinct advantages emerge. Firstly, it reveals gaps in value chain cluster groupings that may be filled through industry recruiting or regional business development strategies. However, not all industries absent from value chain clusters in the region are equally attractive for recruitment. Henceforth, the number of direct and indirect linkages to industries absent from the Eastern Cape Province serves as a measure of their relative attractiveness when considering their recruitment into the region. vi The benchmark value chain cluster framework alone does not explain which agglomeration externalities are generated and exploited within each cluster, but it served as the overarching framework for the remainder of the research. Accordingly, the value chain cluster framework was applied to evidence whether specialisation, competition or diversity (represented by MAR, Porter and Jacobs economies respectively) is the operative mechanism in generating cluster growth in the Eastern Cape Province. Since agglomeration externalities are not directly observable, construct-valid indicators for the various externalities, as well as appropriate mechanisms to empirically assess the statistical relevance of MAR-, Porter and Jacobs economies in stimulating cluster growth, were established. This thesis added to agglomeration literature by disaggregating the standard measure of diversity externalities into two unique diversity indicators, namely supply diversity (SDiv) and use diversity (UDiv). The SDiv- and UDiv coefficients measure the degree to which a value chain cluster’s supplying/user sectoral mix at provincial level differs from that of the cluster grouping at the national level. This distinction between supply-and use diversity developed in this study firstly provides a clearer insight into the relative regional presence of supplying- and using sectors to the various value chain clusters, and secondly, serves as a useful mechanism to regional policymakers in identifying industries that may be targeted for investment into a region. Therefore, by separating the diversity into its two components, a clear distinction can be drawn between the impact of supplying- and using sectors on value chain cluster growth in a particular region. From a narrow perspective, the empirical findings validate both the Marshall Arrow Romer- (small positive impact of regional cluster concentration) and the Jacobs theory (significant positive impact of cluster supply- and use diversity on cluster growth), while it invalidates Porter’s theory (no correlation between competition and cluster performance). The positive effect size recorded between the level of value chain cluster concentration and differential growth indicates that policy makers in the Eastern Cape Province will be well advised to direct growth interventions towards larger concentrated clusters, than towards smaller, incipient value chain clusters. Additionally, vii the effectiveness of targeted inward FDI to the Eastern Cape Province may be raised by evaluating the economic impact against current value chain cluster structure, as well as the effect on the supply- and use diversities of existing value chain clusters in the province. This thesis has also illustrated that value chain clusters that are concentrated in the region, show a positive effect size with the level of supply diversity in the region. Conversely, value chain clusters that reflect high levels of competitiveness record a positive effect size with use diversity. Policy interventions aimed at raising the performance of value chain clusters typified by smaller players in a competitive environment, should therefore consider raising the respective levels of use diversity in the region. This research awakens the proposition that a reliance on a serendipitous approach to generate dynamic externalities is not sufficient, and that certain factor conditions favour the transfer of tacit knowledge between cluster members. Accordingly, this research empirically explored whether statistically significant relationships can be detected between the common cluster elements, or factor conditions, that serve as conduits for the transfer of dynamic externalities and value chain cluster growth in the Eastern Cape Province. The findings indicate that linkages with knowledge generating institutions in the Eastern Cape Province do, albeit to a relatively small extent, have an impact on value chain cluster growth, and validates the assertion that cognitive enhancing institutions contribute to cluster growth. The importance of backward and forward linkages in nurturing regional growth is signified by the moderate effect size recorded by the level of vertical linkages and total value chain cluster growth. Similarly, a moderate effect size was recorded between the level of horizontal linkages and value chain cluster growth, which shows that cooperation amongst competing firms do stimulate cluster and regional growth in the Eastern Cape Province and affirms the proposition that inter-firm linkages on both vertical- and horizontal levels stimulate cluster growth. An expectation was that the institutional framework conditions would have a significant impact on value chain cluster growth in the Eastern Cape Province. However, the empirical findings reflect that the institutional framework conditions have no statistical impact on value chain cluster growth. The study also found a moderate, positive effect size between value chain cluster size (number of employees) and growth, which shows viii that size matters in regional growth. In other words, in contrast to their European counterparts, the larger the number of employees per value chain cluster, the greater the impact on value chain cluster growth in the Eastern Cape Province.
- Full Text:
- Date Issued: 2009