the programmable bride
- Authors: Krueger, Anton
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229698 , vital:49701 , xlink:href="https://hdl.handle.net/10520/EJC156969"
- Description: the man gently opens his machine and finding an agreeable port for his firm flash, he eagerly installs the software he's been waiting on for so very long... once booted up, the man takes his first tentative steps, finding his bride perfect in every way, already completely in love with him, and dreamy... the man tenderly reaches out for her-she understands him so well, she's concerned about his needs, she wants to know how he feels, wants only to please him, she only-/but-there's an interruption/somebody's on the stairs, someone's knocking at his door-the man is forced to close her down a little too abruptly, shutting the machine to attend to other matters while he's away he can't wait to get back, he thinks about her all the time; he longs to flip his laptop lid up, to open her again... but when finally he silently prises open the instrument of his heart's desires, she seems a little disorientated... he didn't shut her down properly …
- Full Text:
- Authors: Krueger, Anton
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/229698 , vital:49701 , xlink:href="https://hdl.handle.net/10520/EJC156969"
- Description: the man gently opens his machine and finding an agreeable port for his firm flash, he eagerly installs the software he's been waiting on for so very long... once booted up, the man takes his first tentative steps, finding his bride perfect in every way, already completely in love with him, and dreamy... the man tenderly reaches out for her-she understands him so well, she's concerned about his needs, she wants to know how he feels, wants only to please him, she only-/but-there's an interruption/somebody's on the stairs, someone's knocking at his door-the man is forced to close her down a little too abruptly, shutting the machine to attend to other matters while he's away he can't wait to get back, he thinks about her all the time; he longs to flip his laptop lid up, to open her again... but when finally he silently prises open the instrument of his heart's desires, she seems a little disorientated... he didn't shut her down properly …
- Full Text:
The relationship between double taxation agreements and the provisions of the South African Income Tax Act
- Authors: Stack, Elizabeth M
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: Article
- Identifier: vital:21102 , http://hdl.handle.net/10962/6384 , http://journals.co.za/content/jefs/7/2/EJC157823
- Description: This article investigates the legal status of Double Taxation Agreements, and the relationship between Double Taxation Agreements, which are concluded in terms of section 108 of the Income Tax Act, and the provisions of the Income Tax Act (taking into account the provisions of the Constitution, and the national and international rules for the interpretation of statutes). An important conclusion reached was that as the Vienna Convention on the Law of Treaties represents customary international law and as such forms part of South African law, the principles contained in the treaty should be taken into account when interpreting South African legislation (including Double Taxation Agreements).The final conclusion of the research was that Double Taxation Agreements have a dual nature – forming part of domestic legislation and being classified as international agreements. The provisions of the Double Taxation Agreement should be taken as overriding any conflicting legislation in the Income Tax Act.
- Full Text:
- Authors: Stack, Elizabeth M
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: Article
- Identifier: vital:21102 , http://hdl.handle.net/10962/6384 , http://journals.co.za/content/jefs/7/2/EJC157823
- Description: This article investigates the legal status of Double Taxation Agreements, and the relationship between Double Taxation Agreements, which are concluded in terms of section 108 of the Income Tax Act, and the provisions of the Income Tax Act (taking into account the provisions of the Constitution, and the national and international rules for the interpretation of statutes). An important conclusion reached was that as the Vienna Convention on the Law of Treaties represents customary international law and as such forms part of South African law, the principles contained in the treaty should be taken into account when interpreting South African legislation (including Double Taxation Agreements).The final conclusion of the research was that Double Taxation Agreements have a dual nature – forming part of domestic legislation and being classified as international agreements. The provisions of the Double Taxation Agreement should be taken as overriding any conflicting legislation in the Income Tax Act.
- Full Text:
The relationship between service quality, customer satisfaction and customer loyalty in the retail supermarket industry
- Authors: Ndhlovu, Thinkwell
- Date: 2014
- Subjects: Consumer satisfaction , Customer loyalty , Customer services -- Rating of , Customer services -- Quality control , Relationship marketing , Supermarkets -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1202 , http://hdl.handle.net/10962/d1013221
- Description: The increasingly competitive business environment has influenced contemporary organisations to build mutual beneficial relationships with their customers indicating a paradigm shift from transactional marketing. In order to compete in this intense competitive environment, organisations are creating competitive advantage over their rivals through service quality that will influence customer satisfaction which subsequently leads to customer loyalty. Service quality has been found to be the key strategy of success and survival for most organisations like retail supermarkets who want to win the loyalty of their customers because of its positive effect on customer satisfaction. The purpose of this research was to determine the relationship between service quality, customer satisfaction and customer loyalty in the retail supermarket industry. An empirical study was conducted in Grahamstown between two main supermarkets through a survey that determined customers’ perceptions on service quality, customer satisfaction and customer loyalty respectively. The empirical findings of this research study revealed that moderate to strong positive linear relationships exists between the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) and customer satisfaction at the 5% level of significance. Furthermore, this study showed that dimensions of service quality (namely physical aspects, reliability, personal interaction and problem solving) have weak negative linear relationships with price sensitivity dimension of customer loyalty. The study further showed that the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) have weak to moderate positive linear relationships with the purchase intentions dimension of customer loyalty. In addition, all the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) showed moderate positive linear relationships with word of mouth communication dimension of customer loyalty. A weak negative linear relationship between price sensitivity dimension of customer loyalty and customer satisfaction was revealed in this study. Purchase intentions dimension of customer loyalty was also found to have a moderate positive linear relationship with customer satisfaction. In addition, word of mouth communication dimension of customer loyalty showed a strong positive linear relationship with customer satisfaction. There is sufficient evidence that the customers of the two supermarkets in this study have different perceptions on problem solving dimension of service quality. This study further provides sufficient evidence of the significant difference between gender on the levels of customer satisfaction. In addition, this study showed that customers of various levels of education and occupations differ in price sensitivity dimension of customer loyalty. The average scores for word of mouth communication, purchase intentions and price sensitivity dimensions of customer loyalty were found to be significantly different between the two supermarkets investigated in this study. Therefore, for supermarkets to compete effectively in the intense retail supermarket industry in South Africa they have to manage their service quality dimensions so as to influence customer satisfaction and customer loyalty respectively.
- Full Text:
- Authors: Ndhlovu, Thinkwell
- Date: 2014
- Subjects: Consumer satisfaction , Customer loyalty , Customer services -- Rating of , Customer services -- Quality control , Relationship marketing , Supermarkets -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1202 , http://hdl.handle.net/10962/d1013221
- Description: The increasingly competitive business environment has influenced contemporary organisations to build mutual beneficial relationships with their customers indicating a paradigm shift from transactional marketing. In order to compete in this intense competitive environment, organisations are creating competitive advantage over their rivals through service quality that will influence customer satisfaction which subsequently leads to customer loyalty. Service quality has been found to be the key strategy of success and survival for most organisations like retail supermarkets who want to win the loyalty of their customers because of its positive effect on customer satisfaction. The purpose of this research was to determine the relationship between service quality, customer satisfaction and customer loyalty in the retail supermarket industry. An empirical study was conducted in Grahamstown between two main supermarkets through a survey that determined customers’ perceptions on service quality, customer satisfaction and customer loyalty respectively. The empirical findings of this research study revealed that moderate to strong positive linear relationships exists between the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) and customer satisfaction at the 5% level of significance. Furthermore, this study showed that dimensions of service quality (namely physical aspects, reliability, personal interaction and problem solving) have weak negative linear relationships with price sensitivity dimension of customer loyalty. The study further showed that the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) have weak to moderate positive linear relationships with the purchase intentions dimension of customer loyalty. In addition, all the dimensions of service quality (namely physical aspects, reliability, personal interaction, problem solving and policy) showed moderate positive linear relationships with word of mouth communication dimension of customer loyalty. A weak negative linear relationship between price sensitivity dimension of customer loyalty and customer satisfaction was revealed in this study. Purchase intentions dimension of customer loyalty was also found to have a moderate positive linear relationship with customer satisfaction. In addition, word of mouth communication dimension of customer loyalty showed a strong positive linear relationship with customer satisfaction. There is sufficient evidence that the customers of the two supermarkets in this study have different perceptions on problem solving dimension of service quality. This study further provides sufficient evidence of the significant difference between gender on the levels of customer satisfaction. In addition, this study showed that customers of various levels of education and occupations differ in price sensitivity dimension of customer loyalty. The average scores for word of mouth communication, purchase intentions and price sensitivity dimensions of customer loyalty were found to be significantly different between the two supermarkets investigated in this study. Therefore, for supermarkets to compete effectively in the intense retail supermarket industry in South Africa they have to manage their service quality dimensions so as to influence customer satisfaction and customer loyalty respectively.
- Full Text:
The rising popularity of Pidgin English radio stations in Nigeria: an audience study of Wazobia FM, Lagos
- Durodola, Olufunke Treasure Anike
- Authors: Durodola, Olufunke Treasure Anike
- Date: 2014
- Subjects: Wazobia FM (Nigeria) , Radio audiences -- Nigeria -- Lagos , Pidgin English -- Nigeria -- Lagos , Radio stations -- Nigeria -- Lagos , Mass media and culture -- Nigeria -- Lagos , Language and languages -- Variation , Popular culture -- Nigeria , Postcolonialism -- Nigeria
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3550 , http://hdl.handle.net/10962/d1020886
- Description: This research is located within media studies and draws on the Cultural Studies approach. It is an audience study, which uses the mixed methods of focus group discussions and an online survey to examine the importance of the use of Nigerian Pidgin as a broadcast language in investigating the rising popularity of Pidgin English radio in a multi-ethnic and multi-lingual Nigeria. The study focuses on Wazobia FM, a radio station in Lagos, and the first pidgin station in Nigeria. It seeks to determine whether the station’s audience engaged with the station’s programming based on its prioritisation of NigP and the linguistic identity it offers them. The study foregrounds the marginalised status of NigP within the politics of language in Nigeria. It traces the language’s evolution through popular and oppositional expressions in broadcasting and in music. It also seeks to establish the place of Pidgin English within the role that language plays in the formation of the Nigerian identity. This study thus adopts the ‘emic’ perspective, which underpins qualitative methodology, and views social life in terms of processes as opposed to static terms. The theoretical framework of this research revolves around culture, language and identity. Pertinent concepts in post-colonial studies, together with conceptual frameworks in Cultural Studies, such as popular culture, representation, hegemony and counter-culture have been used to make sense of the popularity of NigP radio stations.
- Full Text:
- Authors: Durodola, Olufunke Treasure Anike
- Date: 2014
- Subjects: Wazobia FM (Nigeria) , Radio audiences -- Nigeria -- Lagos , Pidgin English -- Nigeria -- Lagos , Radio stations -- Nigeria -- Lagos , Mass media and culture -- Nigeria -- Lagos , Language and languages -- Variation , Popular culture -- Nigeria , Postcolonialism -- Nigeria
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3550 , http://hdl.handle.net/10962/d1020886
- Description: This research is located within media studies and draws on the Cultural Studies approach. It is an audience study, which uses the mixed methods of focus group discussions and an online survey to examine the importance of the use of Nigerian Pidgin as a broadcast language in investigating the rising popularity of Pidgin English radio in a multi-ethnic and multi-lingual Nigeria. The study focuses on Wazobia FM, a radio station in Lagos, and the first pidgin station in Nigeria. It seeks to determine whether the station’s audience engaged with the station’s programming based on its prioritisation of NigP and the linguistic identity it offers them. The study foregrounds the marginalised status of NigP within the politics of language in Nigeria. It traces the language’s evolution through popular and oppositional expressions in broadcasting and in music. It also seeks to establish the place of Pidgin English within the role that language plays in the formation of the Nigerian identity. This study thus adopts the ‘emic’ perspective, which underpins qualitative methodology, and views social life in terms of processes as opposed to static terms. The theoretical framework of this research revolves around culture, language and identity. Pertinent concepts in post-colonial studies, together with conceptual frameworks in Cultural Studies, such as popular culture, representation, hegemony and counter-culture have been used to make sense of the popularity of NigP radio stations.
- Full Text:
The role of computational thinking in introductory computer science
- Authors: Gouws, Lindsey Ann
- Date: 2014
- Subjects: Computer science , Computational complexity , Problem solving -- Study and teaching
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4690 , http://hdl.handle.net/10962/d1011152 , Computer science , Computational complexity , Problem solving -- Study and teaching
- Description: Computational thinking (CT) is gaining recognition as an important skill for students, both in computer science and other disciplines. Although there has been much focus on this field in recent years, it is rarely taught as a formal course, and there is little consensus on what exactly CT entails and how to teach and evaluate it. This research addresses the lack of resources for integrating CT into the introductory computer science curriculum. The question that we aim to answer is whether CT can be evaluated in a meaningful way. A CT framework that outlines the skills and techniques comprising CT and describes the nature of student engagement was developed; this is used as the basis for this research. An assessment (CT test) was then created to gauge the ability of incoming students, and a CT-specfic computer game was developed based on the analysis of an existing game. A set of problem solving strategies and practice activities were then recommended based on criteria defined in the framework. The results revealed that the CT abilities of first year university students are relatively poor, but that the students' scores for the CT test could be used as a predictor for their future success in computer science courses. The framework developed for this research proved successful when applied to the test, computer game evaluation, and classification of strategies and activities. Through this research, we established that CT is a skill that first year computer science students are lacking, and that using CT exercises alongside traditional programming instruction can improve students' learning experiences.
- Full Text:
- Authors: Gouws, Lindsey Ann
- Date: 2014
- Subjects: Computer science , Computational complexity , Problem solving -- Study and teaching
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4690 , http://hdl.handle.net/10962/d1011152 , Computer science , Computational complexity , Problem solving -- Study and teaching
- Description: Computational thinking (CT) is gaining recognition as an important skill for students, both in computer science and other disciplines. Although there has been much focus on this field in recent years, it is rarely taught as a formal course, and there is little consensus on what exactly CT entails and how to teach and evaluate it. This research addresses the lack of resources for integrating CT into the introductory computer science curriculum. The question that we aim to answer is whether CT can be evaluated in a meaningful way. A CT framework that outlines the skills and techniques comprising CT and describes the nature of student engagement was developed; this is used as the basis for this research. An assessment (CT test) was then created to gauge the ability of incoming students, and a CT-specfic computer game was developed based on the analysis of an existing game. A set of problem solving strategies and practice activities were then recommended based on criteria defined in the framework. The results revealed that the CT abilities of first year university students are relatively poor, but that the students' scores for the CT test could be used as a predictor for their future success in computer science courses. The framework developed for this research proved successful when applied to the test, computer game evaluation, and classification of strategies and activities. Through this research, we established that CT is a skill that first year computer science students are lacking, and that using CT exercises alongside traditional programming instruction can improve students' learning experiences.
- Full Text:
The role of knowledge in a democratic society: investigations into mediation and change-oriented learning in water management practices
- Burt, Jane C, Lotz-Sisitka, Heila, Rivers, Nina, Berold, Robert, Ntshudu, Monde, Wigley, Tim, Stanford, Mindy, Jenkin, Treve, Buzani, Mangalisa, Kruger, Ewald
- Authors: Burt, Jane C , Lotz-Sisitka, Heila , Rivers, Nina , Berold, Robert , Ntshudu, Monde , Wigley, Tim , Stanford, Mindy , Jenkin, Treve , Buzani, Mangalisa , Kruger, Ewald
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/436770 , vital:73300 , ISBN 978-1-4312-0519-6 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2074-1-13.pdf
- Description: This project emerged from two previous Water Research Commission (WRC) research projects. In 2006 Heila Lotz-Sisitka and Jane Burt (Lotz-Sisitka, 2006) undertook research on participation in the establishment of integrated water resources management (IWRM) structures. They found that while much emphasis had gone into the establishment of water re-sources management structures, very little attention was being given to building people’s capacity to participate effectively in these structures. Access to and the ability to make use of knowledge resources about wa-ter resources management is a key aspect of such capacity building.
- Full Text:
- Authors: Burt, Jane C , Lotz-Sisitka, Heila , Rivers, Nina , Berold, Robert , Ntshudu, Monde , Wigley, Tim , Stanford, Mindy , Jenkin, Treve , Buzani, Mangalisa , Kruger, Ewald
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/436770 , vital:73300 , ISBN 978-1-4312-0519-6 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2074-1-13.pdf
- Description: This project emerged from two previous Water Research Commission (WRC) research projects. In 2006 Heila Lotz-Sisitka and Jane Burt (Lotz-Sisitka, 2006) undertook research on participation in the establishment of integrated water resources management (IWRM) structures. They found that while much emphasis had gone into the establishment of water re-sources management structures, very little attention was being given to building people’s capacity to participate effectively in these structures. Access to and the ability to make use of knowledge resources about wa-ter resources management is a key aspect of such capacity building.
- Full Text:
The role of the deep spawning grounds in chokka squid (Loligo reynaudi d'orbigny, 1845) recruitment
- Authors: Downey, Nicola Jean
- Date: 2014
- Subjects: Squids -- Spawning -- South Africa Squids -- Effect of temperature on -- South Africa Squids -- Embryos -- South Africa Squids -- South Africa -- Geographical distribution Loligo -- Research -- South Africa Loligo fisheries -- South Africa Recruitment (Population biology) -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5359 , http://hdl.handle.net/10962/d1011867
- Description: It was previously thought that the South African chokka squid Loligo reynaudi is exclusively an inshore, shallow water spawner. Although spawning mostly within shallow bays (<60 m) the presence of squid eggs in trawls at depths up to 130 m indicates this species frequently makes use of deeper spawning areas on the mid-shelf. The extent of mid-shelf spawning (referred to as deep spawning) and the contribution to recruitment has yet to be assessed. Studies have shown mid-shelf bottom temperature to vary considerably from those inshore, suggesting chokka squid spawn in two very different oceanographic environments. Considering these apparent environmental differences, what leads to the mid-shelf environment becoming a suitable spawning habitat? Does a suitable benthic habitat, required for the attachment of egg pods, occur on the mid-shelf? These questions are not only important for determining the extent of deep spawning, but also to the understanding of factors “driving” deep spawning. The fate of deep spawned hatchlings is another unknown. It has been proposed that the main chokka squid inshore spawning grounds are positioned to exploit the net westward currents on the Eastern Agulhas Bank, i.e. paralarvae would be transported west from the hatching site to the cold ridge, an area of high primary and secondary productivity on the Central Agulhas Bank. This concept has come to be known as the Western Transport Hypothesis. Lagrangian ROMS-IBMs (regional ocean model system – individual-based model) predict the net westward transport of paralarvae from both the inshore and deep spawning grounds, to the cold ridge. These simulations were used to investigate the transport of hatchlings to the cold ridge feeding grounds before the exhaustion of yolk reserves. The fate of paralarvae on reaching the feeding grounds has not yet been investigated. This work has contributed new knowledge to our understanding of deep spawning and its role in recruitment. Specific aims of this study were to (1) determine the extent, range and importance of the deep spawning grounds relative to those inshore; (2) investigate the deep spawning ground habitat (Agulhas Bank mid-shelf) morphology and oceanographic environment; (3) determine the transport and survival of deep spawned hatchlings; and (4) investigate the origin and distribution of chokka squid paralarvae on the Agulhas Bank. The extent, depth range and importance of the deep spawning grounds, relative to those inshore was assessed using 23 years of demersal trawl survey data. Data for both the west and south coasts of South Africa were examined for egg capsules. No spawning was found on the west coast. Data showed that chokka squid preferred the Eastern Agulhas Bank for spawning. Spawning occurred not only inshore but also on the mid-shelf extending to depths of 270 m near the shelf edge. The majority of deep spawned eggs however, were found in the depth range 71-130 m. Squid egg density markedly decreased beyond 70 m, suggesting delineation between the inshore and deep spawning grounds. Total egg biomass calculations for depths shallower and deeper than 70 m indicated the coastal area to be strongly favoured, i.e. 82 vs. 18%. These results contest the commonly accepted notion that chokka squid is an inshore spawner and redefine the spawning grounds to extend across the shelf. Apart from an initial study investigating bottom temperature on the mid-shelf, very little is known about the deep spawning habitat. St Francis Bay, a commonly used spawning location, was chosen as a demonstration area for further study. The deep spawning grounds (71-130 m) were mapped and benthic habitat described from underwater video footage. A study investigating cross-shelf bottom conditions was undertaken off Thys Bay. CTD data were used to compare seasonal bottom temperature and oxygen on the St Francis Bay inshore and deep spawning grounds. Squid movement between the two spawning habitats was assessed using filament tagging. Predation and fishing pressure across the spawning grounds was reviewed. The mid-shelf benthic habitat was found to be similar to that inshore and available for spawning. Despite the generally colder bottom temperatures on the mid-shelf, this study showed that bottom temperature in deeper waters can at times be warmer than inshore. Although mid-shelf warming events lasted from a few hours to a number of days, they resulted in similar conditions to those on the inshore spawning grounds. It is likely these events act to expand or shift spawning habitat. The movement of squid between the two spawning habitats makes it possible for them to seek patches of warm bottom water with appropiate substrate. This suggests they are spawning habitat opportunists. Predation and fishing pressure appear to be higher on the inshore spawning grounds. It is feasible that this also forces spawners to seek out more favourable habitat offshore. An individual-based model was used to predict the fate of mid-shelf and inshore hatched paralarvae. Within the model, both the highly productive cold ridge and inshore spawning grounds were considered feeding or nursery areas. Paralarvae were released from six inshore and six deep spawning sites, spanning the coast between Port Alfred and Knysna. All paralarvae not reaching the feeding areas before the exhaustion of yolk-reserves (≤5 days), not retained within the feeding grounds (≥14 days), and not retained on the Agulhas Bank after exiting the feeding grounds were considered lost. This work illustrated the dependence of paralarval transport success on both spawning location and time of hatching, as established in earlier studies. The current IBM has expanded on initial work, emphasizing the importance of the cold ridge and inshore spawning grounds as nursery areas for deep and inshore spawned paralarvae, respectively. This work has highlighted the complex interactions between processes influencing recruitment variability for chokka squid. Possible relationships between periods of highest recruitment success and spawning peaks were identified for both spawning habitats. Based on the likely autumn increase in deep spawning off Tsitsikamma, and the beneficial currents during this period, it can be concluded deep spawning may at times contribute significantly to recruitment. This is particularly true for years where the cold ridge persists into winter. Data on chokka squid paralarval distribution are scarce. Paralarval distribution and abundance, in relation to Agulhas Bank oceanography, was investigated using bongo caught paralarvae and corresponding oceanographic data. Individual-based models (IBMs) were used to predict the origin or spawning site of the wild caught paralarvae, with reference to inshore versus deep spawning. Although failing to predict realistic points of origin, this study provided evidence to support a number of scenarios previously assumed to influence chokka squid recruitment. First is the possible influence of coastal upwelling on the retention, and hence spatial distribution, of paralarvae on the inshore spawning grounds. The second factor thought to impact recruitment is the loss of paralarvae from the Agulhas Bank ecosystem. This study confirmed the removal of paralarvae from the Eastern Agulhas Bank due to Agulhas Current boundary phenomena and resultant offshelf leakage. In addition, data suggested that the formation of the cold ridge could enhance retention on the Central Agulhas Bank, and so prevent offshelf leakage from the Central and Western Agulhas Bank. A synthesis of the main conclusions is presented. Implications of the findings and directions for future research are discussed.
- Full Text:
- Authors: Downey, Nicola Jean
- Date: 2014
- Subjects: Squids -- Spawning -- South Africa Squids -- Effect of temperature on -- South Africa Squids -- Embryos -- South Africa Squids -- South Africa -- Geographical distribution Loligo -- Research -- South Africa Loligo fisheries -- South Africa Recruitment (Population biology) -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5359 , http://hdl.handle.net/10962/d1011867
- Description: It was previously thought that the South African chokka squid Loligo reynaudi is exclusively an inshore, shallow water spawner. Although spawning mostly within shallow bays (<60 m) the presence of squid eggs in trawls at depths up to 130 m indicates this species frequently makes use of deeper spawning areas on the mid-shelf. The extent of mid-shelf spawning (referred to as deep spawning) and the contribution to recruitment has yet to be assessed. Studies have shown mid-shelf bottom temperature to vary considerably from those inshore, suggesting chokka squid spawn in two very different oceanographic environments. Considering these apparent environmental differences, what leads to the mid-shelf environment becoming a suitable spawning habitat? Does a suitable benthic habitat, required for the attachment of egg pods, occur on the mid-shelf? These questions are not only important for determining the extent of deep spawning, but also to the understanding of factors “driving” deep spawning. The fate of deep spawned hatchlings is another unknown. It has been proposed that the main chokka squid inshore spawning grounds are positioned to exploit the net westward currents on the Eastern Agulhas Bank, i.e. paralarvae would be transported west from the hatching site to the cold ridge, an area of high primary and secondary productivity on the Central Agulhas Bank. This concept has come to be known as the Western Transport Hypothesis. Lagrangian ROMS-IBMs (regional ocean model system – individual-based model) predict the net westward transport of paralarvae from both the inshore and deep spawning grounds, to the cold ridge. These simulations were used to investigate the transport of hatchlings to the cold ridge feeding grounds before the exhaustion of yolk reserves. The fate of paralarvae on reaching the feeding grounds has not yet been investigated. This work has contributed new knowledge to our understanding of deep spawning and its role in recruitment. Specific aims of this study were to (1) determine the extent, range and importance of the deep spawning grounds relative to those inshore; (2) investigate the deep spawning ground habitat (Agulhas Bank mid-shelf) morphology and oceanographic environment; (3) determine the transport and survival of deep spawned hatchlings; and (4) investigate the origin and distribution of chokka squid paralarvae on the Agulhas Bank. The extent, depth range and importance of the deep spawning grounds, relative to those inshore was assessed using 23 years of demersal trawl survey data. Data for both the west and south coasts of South Africa were examined for egg capsules. No spawning was found on the west coast. Data showed that chokka squid preferred the Eastern Agulhas Bank for spawning. Spawning occurred not only inshore but also on the mid-shelf extending to depths of 270 m near the shelf edge. The majority of deep spawned eggs however, were found in the depth range 71-130 m. Squid egg density markedly decreased beyond 70 m, suggesting delineation between the inshore and deep spawning grounds. Total egg biomass calculations for depths shallower and deeper than 70 m indicated the coastal area to be strongly favoured, i.e. 82 vs. 18%. These results contest the commonly accepted notion that chokka squid is an inshore spawner and redefine the spawning grounds to extend across the shelf. Apart from an initial study investigating bottom temperature on the mid-shelf, very little is known about the deep spawning habitat. St Francis Bay, a commonly used spawning location, was chosen as a demonstration area for further study. The deep spawning grounds (71-130 m) were mapped and benthic habitat described from underwater video footage. A study investigating cross-shelf bottom conditions was undertaken off Thys Bay. CTD data were used to compare seasonal bottom temperature and oxygen on the St Francis Bay inshore and deep spawning grounds. Squid movement between the two spawning habitats was assessed using filament tagging. Predation and fishing pressure across the spawning grounds was reviewed. The mid-shelf benthic habitat was found to be similar to that inshore and available for spawning. Despite the generally colder bottom temperatures on the mid-shelf, this study showed that bottom temperature in deeper waters can at times be warmer than inshore. Although mid-shelf warming events lasted from a few hours to a number of days, they resulted in similar conditions to those on the inshore spawning grounds. It is likely these events act to expand or shift spawning habitat. The movement of squid between the two spawning habitats makes it possible for them to seek patches of warm bottom water with appropiate substrate. This suggests they are spawning habitat opportunists. Predation and fishing pressure appear to be higher on the inshore spawning grounds. It is feasible that this also forces spawners to seek out more favourable habitat offshore. An individual-based model was used to predict the fate of mid-shelf and inshore hatched paralarvae. Within the model, both the highly productive cold ridge and inshore spawning grounds were considered feeding or nursery areas. Paralarvae were released from six inshore and six deep spawning sites, spanning the coast between Port Alfred and Knysna. All paralarvae not reaching the feeding areas before the exhaustion of yolk-reserves (≤5 days), not retained within the feeding grounds (≥14 days), and not retained on the Agulhas Bank after exiting the feeding grounds were considered lost. This work illustrated the dependence of paralarval transport success on both spawning location and time of hatching, as established in earlier studies. The current IBM has expanded on initial work, emphasizing the importance of the cold ridge and inshore spawning grounds as nursery areas for deep and inshore spawned paralarvae, respectively. This work has highlighted the complex interactions between processes influencing recruitment variability for chokka squid. Possible relationships between periods of highest recruitment success and spawning peaks were identified for both spawning habitats. Based on the likely autumn increase in deep spawning off Tsitsikamma, and the beneficial currents during this period, it can be concluded deep spawning may at times contribute significantly to recruitment. This is particularly true for years where the cold ridge persists into winter. Data on chokka squid paralarval distribution are scarce. Paralarval distribution and abundance, in relation to Agulhas Bank oceanography, was investigated using bongo caught paralarvae and corresponding oceanographic data. Individual-based models (IBMs) were used to predict the origin or spawning site of the wild caught paralarvae, with reference to inshore versus deep spawning. Although failing to predict realistic points of origin, this study provided evidence to support a number of scenarios previously assumed to influence chokka squid recruitment. First is the possible influence of coastal upwelling on the retention, and hence spatial distribution, of paralarvae on the inshore spawning grounds. The second factor thought to impact recruitment is the loss of paralarvae from the Agulhas Bank ecosystem. This study confirmed the removal of paralarvae from the Eastern Agulhas Bank due to Agulhas Current boundary phenomena and resultant offshelf leakage. In addition, data suggested that the formation of the cold ridge could enhance retention on the Central Agulhas Bank, and so prevent offshelf leakage from the Central and Western Agulhas Bank. A synthesis of the main conclusions is presented. Implications of the findings and directions for future research are discussed.
- Full Text:
The Seduction of Ash: " Mia Couto's" The Day Mabata-bata Exploded" and" The Bird-Dreaming Baobab
- Authors: Njovane, Thandokazi
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142702 , vital:38103 , 10.4314/eia.v41i2.2
- Description: Chesca Long-Innes argues that Mia Couto's installation of the fantastic in his short story collection, Voices Made Night, may best be understood "not so much as a product of any 'magical realist' poetics, but as 'naturalised,' or motivated as a function of the collective neurosis of a [Mozambican] society traumatised by its continuing history of poverty and extreme violence". Couto's use of the fantastic, she adds, encompasses both empirical and psychic reality, and both are characterised by instability and elusiveness. The collection, she then maintains, constitutes a reinvention or reimagining of subjective realities constructed and perpetuated by the social trauma underpinning what she terms the "psycho-pathology of post-colonial Mozambique, in which the society as a whole is [. . .] caught in the grip of a profound depression or melancholia".
- Full Text:
- Authors: Njovane, Thandokazi
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/142702 , vital:38103 , 10.4314/eia.v41i2.2
- Description: Chesca Long-Innes argues that Mia Couto's installation of the fantastic in his short story collection, Voices Made Night, may best be understood "not so much as a product of any 'magical realist' poetics, but as 'naturalised,' or motivated as a function of the collective neurosis of a [Mozambican] society traumatised by its continuing history of poverty and extreme violence". Couto's use of the fantastic, she adds, encompasses both empirical and psychic reality, and both are characterised by instability and elusiveness. The collection, she then maintains, constitutes a reinvention or reimagining of subjective realities constructed and perpetuated by the social trauma underpinning what she terms the "psycho-pathology of post-colonial Mozambique, in which the society as a whole is [. . .] caught in the grip of a profound depression or melancholia".
- Full Text:
The transformers : journalism education
- Authors: Priscilla Boshoff
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70688 , vital:29689
- Description: Universities are strange places. People come in as one kind of being, and leave quite different. They are places of transformation. One way in which they effect this transformation is to challenge our preconceived notions of the world, and our relationship to it. However, at the same time, universities are also places of privilege and so can be conservative – in the sense of conserving and fostering particular interests in their favour.
- Full Text:
- Authors: Priscilla Boshoff
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70688 , vital:29689
- Description: Universities are strange places. People come in as one kind of being, and leave quite different. They are places of transformation. One way in which they effect this transformation is to challenge our preconceived notions of the world, and our relationship to it. However, at the same time, universities are also places of privilege and so can be conservative – in the sense of conserving and fostering particular interests in their favour.
- Full Text:
The transformers: journalism education
- Authors: Boshoff, Priscilla A
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141911 , vital:38015 , http://journals.co.za/content/rujr/2014/34/EJC159497
- Description: Universities are strange places. People come in as one kind of being, and leave quite different. They are places of transformation. One way in which they effect this transformation is to challenge our preconceived notions of the world, and our relationship to it. However, at the same time, universities are also places of privilege and so can be conservative – in the sense of conserving and fostering particular interests in their favour.
- Full Text:
- Authors: Boshoff, Priscilla A
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141911 , vital:38015 , http://journals.co.za/content/rujr/2014/34/EJC159497
- Description: Universities are strange places. People come in as one kind of being, and leave quite different. They are places of transformation. One way in which they effect this transformation is to challenge our preconceived notions of the world, and our relationship to it. However, at the same time, universities are also places of privilege and so can be conservative – in the sense of conserving and fostering particular interests in their favour.
- Full Text:
The water and nutrient potential of brewery effluent for hydroponic tomato production
- Authors: Power, Sean Duncan
- Date: 2014
- Subjects: Hydroponics , Tomatoes -- Breeding , Brewery waste , Water -- Purification , Algae culture , Algae -- Biotechnology , Nitric acid , Phosphoric acid
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5358 , http://hdl.handle.net/10962/d1011604 , Hydroponics , Tomatoes -- Breeding , Brewery waste , Water -- Purification , Algae culture , Algae -- Biotechnology , Nitric acid , Phosphoric acid
- Description: Brewery effluent that had undergone treatment in an anaerobic digester (AD) was used as an alternative water and nutrient source for hydroponic crop production. Brewery effluent was demonstrated to contain sufficient nutrients to support the growth, flowering and fruiting of Lycopersicum escolentum "Moneymaker" tomato crops. The adjustment of the effluent pH with phosphoric acid to between pH 6.0 and 6.5 increased the development of the crops by around 100% compared to crops grown in unaltered effluent. The pH adjusted effluent-grown plants grew to a mean height of 831.4 ± 21.1 mm and a dry biomass weight of 42.34 ± 2.76 g compared to the unaltered pH effluent plants which grew to a height of 410.6 ± 20.5 mm and a weight of 7.65 ± 0.68 g after 49 days. Effluent treatment in high-rate algal ponds (HRAP) was determined to have no positive effect on the nutritional potential of the effluent for Moneymaker production. The effluent-grown plants did not perform as well as plants grown in inorganic-fertilizer and municipal water. Plants grown in effluent grew taller but did not produce significantly more fruit when phosphoric acid (height: 1573.3 ± 50.4 mm, 19.4 ± 1.4 fruit per plant) was compared to nitric acid (height: 1254.1 ± 25.4 mm, 15.6 ± 1.5 fruit per plant) as the pH adjustment over 72 days. Direct and secondary plant stresses from effluent alkalinity, ammonium nutrition, nitrogen limitation, sodium concentrations and heat stress among other factors were probably confounding variables in these trials and require further investigation. Considering the raw effluent composition and manipulating the AD operation is a potential opportunity to improve overall AD performance, reduce chemical inputs in the effluent treatment process, reduce the final effluent alkalinity, and increase available nitrogen content in the final effluent. The anaerobic digester discharging >1000 m³ of nutrient enriched effluent every day is a resource with considerable potential. The benefits of developing this resource can contribute to cost-reduction at the brewery, more efficient water, nutrient and energy management at the brewery, and offer opportunities for job creation and potentially benefit local food security.
- Full Text:
- Authors: Power, Sean Duncan
- Date: 2014
- Subjects: Hydroponics , Tomatoes -- Breeding , Brewery waste , Water -- Purification , Algae culture , Algae -- Biotechnology , Nitric acid , Phosphoric acid
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5358 , http://hdl.handle.net/10962/d1011604 , Hydroponics , Tomatoes -- Breeding , Brewery waste , Water -- Purification , Algae culture , Algae -- Biotechnology , Nitric acid , Phosphoric acid
- Description: Brewery effluent that had undergone treatment in an anaerobic digester (AD) was used as an alternative water and nutrient source for hydroponic crop production. Brewery effluent was demonstrated to contain sufficient nutrients to support the growth, flowering and fruiting of Lycopersicum escolentum "Moneymaker" tomato crops. The adjustment of the effluent pH with phosphoric acid to between pH 6.0 and 6.5 increased the development of the crops by around 100% compared to crops grown in unaltered effluent. The pH adjusted effluent-grown plants grew to a mean height of 831.4 ± 21.1 mm and a dry biomass weight of 42.34 ± 2.76 g compared to the unaltered pH effluent plants which grew to a height of 410.6 ± 20.5 mm and a weight of 7.65 ± 0.68 g after 49 days. Effluent treatment in high-rate algal ponds (HRAP) was determined to have no positive effect on the nutritional potential of the effluent for Moneymaker production. The effluent-grown plants did not perform as well as plants grown in inorganic-fertilizer and municipal water. Plants grown in effluent grew taller but did not produce significantly more fruit when phosphoric acid (height: 1573.3 ± 50.4 mm, 19.4 ± 1.4 fruit per plant) was compared to nitric acid (height: 1254.1 ± 25.4 mm, 15.6 ± 1.5 fruit per plant) as the pH adjustment over 72 days. Direct and secondary plant stresses from effluent alkalinity, ammonium nutrition, nitrogen limitation, sodium concentrations and heat stress among other factors were probably confounding variables in these trials and require further investigation. Considering the raw effluent composition and manipulating the AD operation is a potential opportunity to improve overall AD performance, reduce chemical inputs in the effluent treatment process, reduce the final effluent alkalinity, and increase available nitrogen content in the final effluent. The anaerobic digester discharging >1000 m³ of nutrient enriched effluent every day is a resource with considerable potential. The benefits of developing this resource can contribute to cost-reduction at the brewery, more efficient water, nutrient and energy management at the brewery, and offer opportunities for job creation and potentially benefit local food security.
- Full Text:
Thermoluminescence characteristics of synthetic quartz
- Authors: Niyonzima, Pontien
- Date: 2014
- Subjects: Thermoluminescence , Quartz , Emission spectroscopy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5538 , http://hdl.handle.net/10962/d1013190
- Description: Quartz is one of the most abundant natural minerals in the crust of the earth. Due to its dosimetric luminescence properties, it is employed in retrospective dosimetry, archaeological and geological dating. The intensity and the structure of the TL glow curves of quartz are strongly dependent upon the origin, impurity content, formation condition and pre-irradiation heat treatment. The aim of this project is to study the mechanisms of thermoluminescence (TL), Phototranssferred thermoluminescence (PTTL) and radioluminescence (RL) in synthetic quartz and to discuss the results in terms of physical characteristics of point defects involved. Thermoluminescence measurements were made on a sample of synthetic quartz in its as-received state (unannealed) synthetic quartz annealed at 500˚C for 10 minutes. The unannealed sample shows six TL glow peaks located at 94, 116, 176, 212, 280 and 348˚C at a heating rate of 5˚Cs⁻¹. The annealed sample shows seven TL peaks at 115, 148, 214, 246, 300, 348 and 412˚C at a heating rate of 5˚Cs⁻¹. The intensity of peak I, at 94 and 115˚C for the unannealed and annealed samples respectively, increases with irradiation. Peak I has an activation energy of approximately 0.90 eV and a frequency factor of the order of 10¹¹ s⁻¹. The order of kinetics is between 0.9 and 1.2. The unannealed synthetic quartz shows phototransferred thermoluminescence (PTTL) at the position of peak I after removal of the first three peaks followed by illumination. The PTTL intensities show peak shaped behaviour when plotted against illumination time. The PTTL showed a quadratic increase with dose. The material exhibits fading of PTTL intensity with delay time. Radioluminescence was measured on synthetic quartz unannealed and annealed annealed at 500, 600, 700, 800, 900 and 1000˚C for 10 to 60 min. The emission spectra of synthetic quartz show seven emission bands. The effect of irradiation on the RL spectra is to increase the intensity of all emission bands for samples annealed at temperatures less than or equal to 700˚C. The effect of annealing time is to increase the RL amplitude for the samples annealed at temperatures greater than 700˚C. The annealing temperature increases the RL amplitude of all emission bands of the spectrum for all samples.
- Full Text:
- Authors: Niyonzima, Pontien
- Date: 2014
- Subjects: Thermoluminescence , Quartz , Emission spectroscopy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5538 , http://hdl.handle.net/10962/d1013190
- Description: Quartz is one of the most abundant natural minerals in the crust of the earth. Due to its dosimetric luminescence properties, it is employed in retrospective dosimetry, archaeological and geological dating. The intensity and the structure of the TL glow curves of quartz are strongly dependent upon the origin, impurity content, formation condition and pre-irradiation heat treatment. The aim of this project is to study the mechanisms of thermoluminescence (TL), Phototranssferred thermoluminescence (PTTL) and radioluminescence (RL) in synthetic quartz and to discuss the results in terms of physical characteristics of point defects involved. Thermoluminescence measurements were made on a sample of synthetic quartz in its as-received state (unannealed) synthetic quartz annealed at 500˚C for 10 minutes. The unannealed sample shows six TL glow peaks located at 94, 116, 176, 212, 280 and 348˚C at a heating rate of 5˚Cs⁻¹. The annealed sample shows seven TL peaks at 115, 148, 214, 246, 300, 348 and 412˚C at a heating rate of 5˚Cs⁻¹. The intensity of peak I, at 94 and 115˚C for the unannealed and annealed samples respectively, increases with irradiation. Peak I has an activation energy of approximately 0.90 eV and a frequency factor of the order of 10¹¹ s⁻¹. The order of kinetics is between 0.9 and 1.2. The unannealed synthetic quartz shows phototransferred thermoluminescence (PTTL) at the position of peak I after removal of the first three peaks followed by illumination. The PTTL intensities show peak shaped behaviour when plotted against illumination time. The PTTL showed a quadratic increase with dose. The material exhibits fading of PTTL intensity with delay time. Radioluminescence was measured on synthetic quartz unannealed and annealed annealed at 500, 600, 700, 800, 900 and 1000˚C for 10 to 60 min. The emission spectra of synthetic quartz show seven emission bands. The effect of irradiation on the RL spectra is to increase the intensity of all emission bands for samples annealed at temperatures less than or equal to 700˚C. The effect of annealing time is to increase the RL amplitude for the samples annealed at temperatures greater than 700˚C. The annealing temperature increases the RL amplitude of all emission bands of the spectrum for all samples.
- Full Text:
Thermoluminescence of natural quartz
- Authors: Lontsi Sob, Aaron Joel
- Date: 2014
- Subjects: Thermoluminescence , Quartz , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5543 , http://hdl.handle.net/10962/d1013358
- Description: The kinetic and dosimetric features of the main thermoluminescence peak of quartz have been investigated in unannealed as well in quartz annealed at 500˚C for 10 minutes. The main peak is found at 92 and 86˚C respectively for aliquots of unannealed and annealed samples irradiated to 10 Gy and heated at 5.0˚C/s. For each sample, the intensity of the main peak is enhanced with repetitive measurement whereas its maximum temperature is unaffected. The peak position of the main peak in each sample is independent of the irradiation dose and this, together with its fading characteristics are consistent with first-order kinetics. For low doses, typically between 2 and 10 Gy, the dose response of the main peak in each sample is linear. In the intermediate dose range from 10 to 60 Gy, the growth of the main peak in each sample is sub-linear and for greater doses, in the range from 60 Gy to 151 Gy, it is linear again. The half-life of the main peak of the unannealed sample is about 1.3 h whereas that of the annealed sample is about 1.2 h. The main peak in each sample can be approximated to a first-order glow peak. As the heating rate increases, the intensity of the main peak in each sample decreases. This is evidence of thermal quenching. The main peak in each sample is the only peak regenerated by phototransfer. The resulting phototransferred peak occurs at the same temperature as the original peak and has similar kinetic and dosimetric features. For a preheat temperature of 120˚C, the intensity of the phototransferred peak in each sample increases with illumination time up to a maximum and decreases afterwards. At longer illumination times (such as 30 min up to 1 h), no further decrease in the intensity of the phototransferred peak is observed. The traps associated with the 325˚C peak are the main source of the electrons responsible for the regenerated peak. Radioluminescence emission spectra were also measured for quartz annealed at various temperatures. Emission bands in quartz are affected by annealing and irradiation. A strong enhancement of the 3.4 eV (~366 nm) emission band is observed in quartz annealed at 500˚C. A new emission band which grows with annealing up to 1000˚C is observed at 3.7 eV (~330 nm) for quartz annealed at 600˚C. An attempt has been made to correlate the changes in radioluminescence emission spectra due to annealing with the influence of annealing on luminescence lifetimes in quartz.
- Full Text:
- Authors: Lontsi Sob, Aaron Joel
- Date: 2014
- Subjects: Thermoluminescence , Quartz , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5543 , http://hdl.handle.net/10962/d1013358
- Description: The kinetic and dosimetric features of the main thermoluminescence peak of quartz have been investigated in unannealed as well in quartz annealed at 500˚C for 10 minutes. The main peak is found at 92 and 86˚C respectively for aliquots of unannealed and annealed samples irradiated to 10 Gy and heated at 5.0˚C/s. For each sample, the intensity of the main peak is enhanced with repetitive measurement whereas its maximum temperature is unaffected. The peak position of the main peak in each sample is independent of the irradiation dose and this, together with its fading characteristics are consistent with first-order kinetics. For low doses, typically between 2 and 10 Gy, the dose response of the main peak in each sample is linear. In the intermediate dose range from 10 to 60 Gy, the growth of the main peak in each sample is sub-linear and for greater doses, in the range from 60 Gy to 151 Gy, it is linear again. The half-life of the main peak of the unannealed sample is about 1.3 h whereas that of the annealed sample is about 1.2 h. The main peak in each sample can be approximated to a first-order glow peak. As the heating rate increases, the intensity of the main peak in each sample decreases. This is evidence of thermal quenching. The main peak in each sample is the only peak regenerated by phototransfer. The resulting phototransferred peak occurs at the same temperature as the original peak and has similar kinetic and dosimetric features. For a preheat temperature of 120˚C, the intensity of the phototransferred peak in each sample increases with illumination time up to a maximum and decreases afterwards. At longer illumination times (such as 30 min up to 1 h), no further decrease in the intensity of the phototransferred peak is observed. The traps associated with the 325˚C peak are the main source of the electrons responsible for the regenerated peak. Radioluminescence emission spectra were also measured for quartz annealed at various temperatures. Emission bands in quartz are affected by annealing and irradiation. A strong enhancement of the 3.4 eV (~366 nm) emission band is observed in quartz annealed at 500˚C. A new emission band which grows with annealing up to 1000˚C is observed at 3.7 eV (~330 nm) for quartz annealed at 600˚C. An attempt has been made to correlate the changes in radioluminescence emission spectra due to annealing with the influence of annealing on luminescence lifetimes in quartz.
- Full Text:
Thermoluminescence of secondary glow peaks in carbon-doped aluminium oxide
- Authors: Seneza, Cleophace
- Date: 2014
- Subjects: Thermoluminescence , Aluminum oxide , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5537 , http://hdl.handle.net/10962/d1013053
- Description: Carbon-doped aluminium oxide, α-Al₂O₃ : C, is a highly sensitive luminescence dosimeter. The high sensitivity of α-Al₂O₃ : C has been attributed to large concentrations of oxygen vacancies, F and F⁺ centres, induced in the material during its preparation. The material is prepared in a highly reducing atmosphere in the presence of carbon. In the luminescence process, electrons are trapped in F-centre defects as a result of irradiation of the material. Thermal or optical release of trapped electrons leads to emission of light, thermoluminescence (TL) or optically stimulated light (OSL) respectively. The thermoluminescence technique is used to study point defects involved in luminescence of α-Al₂O₃ : C. A glow curve of α-Al₂O₃ : C, generally, shows three peaks; the main dosimetric peak of high intensity (peak II) and two other peaks of lower intensity called secondary glow peaks (peaks I and III). The overall aim of our work was to study the TL mechanisms responsible for secondary glow peaks in α-Al₂O₃ : C. The dynamics of charge movement between centres during the TL process was studied. The phototransferred thermoluminescence (PTTL) from secondary glow peaks was also studied. The kinetic analysis of TL from secondary peaks has shown that the activation energy of peak I is 0.7 eV and that of peak III, 1.2 eV. The frequency factor, the frequency at which an electron attempts to escape a trap, was found near the range of the Debye vibration frequency. Values of the activation energy are consistent within a variety of methods used. The two peaks follow first order kinetics as confirmed by the TM-Tstop method. A linear dependence of TL from peak I on dose is observed at various doses from 0.5 to 2.5 Gy. The peak position for peak I was also independent on dose, further confirmation that peak I is of first order kinetics. Peak I suffers from thermal fading with storage with a half-life of about 120 s. The dependence of TL intensity for peak I increased as a function of heating rate from 0.2 to 6ºCs⁻¹. In contrast to the TL intensity for peak I, the intensity of TL for peak III decreases with an increase of heating rate from 0.2 to 6ºCs⁻¹. This is evidence of thermal quenching for peak III. Parameters W = 1.48 ± 0:10 eV and C = 4 x 10¹³ of thermal quenching were calculated from peak III intensities at different heating rates. Thermal cleaning of peak III and the glow curve deconvolution methods confirmed that the main peak is actually overlapped by a small peak (labeled peak IIA). The kinetic analysis of peak IIA showed that it is of first order kinetics and that its activation energy is 1:0 eV. In addition, the peak IIA is affected by thermal quenching. Another secondary peak appears at 422ºC (peak IV). However, the kinetic analysis of TL from peak IV was not studied because its intensity is not well defined. A heating rate of 0.4ºCs⁻¹ was used after a dose of 3 Gy in kinetic analysis of peaks IIA and III. The study of the PTTL showed that peaks I and II were regenerated under PTTL but peak III was not. Various effects of the PTTL for peaks I and II for different preheating temperatures in different samples were observed. The effect of annealing at 900ºC for 15 minutes between measurements following each illumination time was studied. The effect of dose on secondary peaks was also studied in this work. The kinetic analysis of the PTTL intensity for peak I showed that its activation energy is 0.7 eV, consistent with the activation energy of the normal TL for peak I. The PTTL intensity from peak I fades rapidly with storage compared with the thermal fading from peak I of the normal TL. The PTTL intensity for peak I decreases as a function of heating rate. This decrease was attributed to thermal quenching. Thermal quenching was not observed in the case of the normal TL intensity. The cause of this contrast requires further study.
- Full Text:
- Authors: Seneza, Cleophace
- Date: 2014
- Subjects: Thermoluminescence , Aluminum oxide , Thermoluminescence dosimetry
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5537 , http://hdl.handle.net/10962/d1013053
- Description: Carbon-doped aluminium oxide, α-Al₂O₃ : C, is a highly sensitive luminescence dosimeter. The high sensitivity of α-Al₂O₃ : C has been attributed to large concentrations of oxygen vacancies, F and F⁺ centres, induced in the material during its preparation. The material is prepared in a highly reducing atmosphere in the presence of carbon. In the luminescence process, electrons are trapped in F-centre defects as a result of irradiation of the material. Thermal or optical release of trapped electrons leads to emission of light, thermoluminescence (TL) or optically stimulated light (OSL) respectively. The thermoluminescence technique is used to study point defects involved in luminescence of α-Al₂O₃ : C. A glow curve of α-Al₂O₃ : C, generally, shows three peaks; the main dosimetric peak of high intensity (peak II) and two other peaks of lower intensity called secondary glow peaks (peaks I and III). The overall aim of our work was to study the TL mechanisms responsible for secondary glow peaks in α-Al₂O₃ : C. The dynamics of charge movement between centres during the TL process was studied. The phototransferred thermoluminescence (PTTL) from secondary glow peaks was also studied. The kinetic analysis of TL from secondary peaks has shown that the activation energy of peak I is 0.7 eV and that of peak III, 1.2 eV. The frequency factor, the frequency at which an electron attempts to escape a trap, was found near the range of the Debye vibration frequency. Values of the activation energy are consistent within a variety of methods used. The two peaks follow first order kinetics as confirmed by the TM-Tstop method. A linear dependence of TL from peak I on dose is observed at various doses from 0.5 to 2.5 Gy. The peak position for peak I was also independent on dose, further confirmation that peak I is of first order kinetics. Peak I suffers from thermal fading with storage with a half-life of about 120 s. The dependence of TL intensity for peak I increased as a function of heating rate from 0.2 to 6ºCs⁻¹. In contrast to the TL intensity for peak I, the intensity of TL for peak III decreases with an increase of heating rate from 0.2 to 6ºCs⁻¹. This is evidence of thermal quenching for peak III. Parameters W = 1.48 ± 0:10 eV and C = 4 x 10¹³ of thermal quenching were calculated from peak III intensities at different heating rates. Thermal cleaning of peak III and the glow curve deconvolution methods confirmed that the main peak is actually overlapped by a small peak (labeled peak IIA). The kinetic analysis of peak IIA showed that it is of first order kinetics and that its activation energy is 1:0 eV. In addition, the peak IIA is affected by thermal quenching. Another secondary peak appears at 422ºC (peak IV). However, the kinetic analysis of TL from peak IV was not studied because its intensity is not well defined. A heating rate of 0.4ºCs⁻¹ was used after a dose of 3 Gy in kinetic analysis of peaks IIA and III. The study of the PTTL showed that peaks I and II were regenerated under PTTL but peak III was not. Various effects of the PTTL for peaks I and II for different preheating temperatures in different samples were observed. The effect of annealing at 900ºC for 15 minutes between measurements following each illumination time was studied. The effect of dose on secondary peaks was also studied in this work. The kinetic analysis of the PTTL intensity for peak I showed that its activation energy is 0.7 eV, consistent with the activation energy of the normal TL for peak I. The PTTL intensity from peak I fades rapidly with storage compared with the thermal fading from peak I of the normal TL. The PTTL intensity for peak I decreases as a function of heating rate. This decrease was attributed to thermal quenching. Thermal quenching was not observed in the case of the normal TL intensity. The cause of this contrast requires further study.
- Full Text:
Thinking academic freedom
- Authors: Lange, Lis
- Date: 2014
- Subjects: Academic Freedom -- South Africa Universities and colleges -- South Africa Equality Liberty Education and state -- South Africa Education, Higher -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/784 , vital:19990
- Description: I have titled this lecture Thinking Academic Freedom, because I would like to make thinking in the Arendtian sense the axis along which to organise this exposition. It was interesting for me that when I sent the title of the lecture I was asked whether I meant thinking or rethinking. It is true that we tend to rethink, revisit and review in the titles of our lectures and papers. This usually means that the accent is not so much on the act of thinking but on the object we are trying to examine. For this occasion, I would like to make the act of thinking itself as important an aspect of the lecture as the issue of academic freedom itself. What interests me is to explore the nature of our work as academics and how this relates to the notion of academic freedom. So, this is my proposed itinerary: I will first stop to flag some of the issues we all know about, current debates on academic freedom which inevitably constitute one layer of the background for these reflections; then I would like to explore with the lens of Hannah Arendt's political thinking the meaning of freedom and thinking in relation to the life of academics. I will then complicate matters further by jumping from Arendt to Pierre Bourdieu's Homo Academicus, after which I hope to land in the not too comfortable terrain of a call to action.
- Full Text:
- Authors: Lange, Lis
- Date: 2014
- Subjects: Academic Freedom -- South Africa Universities and colleges -- South Africa Equality Liberty Education and state -- South Africa Education, Higher -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/784 , vital:19990
- Description: I have titled this lecture Thinking Academic Freedom, because I would like to make thinking in the Arendtian sense the axis along which to organise this exposition. It was interesting for me that when I sent the title of the lecture I was asked whether I meant thinking or rethinking. It is true that we tend to rethink, revisit and review in the titles of our lectures and papers. This usually means that the accent is not so much on the act of thinking but on the object we are trying to examine. For this occasion, I would like to make the act of thinking itself as important an aspect of the lecture as the issue of academic freedom itself. What interests me is to explore the nature of our work as academics and how this relates to the notion of academic freedom. So, this is my proposed itinerary: I will first stop to flag some of the issues we all know about, current debates on academic freedom which inevitably constitute one layer of the background for these reflections; then I would like to explore with the lens of Hannah Arendt's political thinking the meaning of freedom and thinking in relation to the life of academics. I will then complicate matters further by jumping from Arendt to Pierre Bourdieu's Homo Academicus, after which I hope to land in the not too comfortable terrain of a call to action.
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Thinking Africa Newsletter: (June 2014)
- Authors: Matthews, Sally
- Date: 2014
- Language: English
- Type: text , article
- Identifier: vital:38065 , http://hdl.handle.net/20.500.12137/23
- Description: Thinking Africa Newsletter (June 2014).
- Full Text:
- Authors: Matthews, Sally
- Date: 2014
- Language: English
- Type: text , article
- Identifier: vital:38065 , http://hdl.handle.net/20.500.12137/23
- Description: Thinking Africa Newsletter (June 2014).
- Full Text:
Thinking Africa Newsletter: (March 2014)
- Authors: Matthews, Sally
- Date: 2014
- Language: English
- Type: text , article
- Identifier: vital:38067 , http://hdl.handle.net/20.500.12137/22
- Description: Thinking Africa Newsletter (March 2014).
- Full Text:
- Authors: Matthews, Sally
- Date: 2014
- Language: English
- Type: text , article
- Identifier: vital:38067 , http://hdl.handle.net/20.500.12137/22
- Description: Thinking Africa Newsletter (March 2014).
- Full Text:
Tourism and development : a case study of Mdumbi Backpackers and Transcape non-profit organisation
- Authors: Hitchcock, Kelly Alexandra
- Date: 2014
- Subjects: Mdumbi Backpackers -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape -- Planning , Backpacking -- South Africa -- Eastern Cape -- Case studies , Black people -- Employment -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3377 , http://hdl.handle.net/10962/d1013143
- Description: The former Transkei region of the Eastern Cape of South Africa, in common with many of the other former Bantustans, is currently facing a developmental backlog. It is one of the poorest regions of the country and is a direct product of South Africa’s history of colonisation and geopolitical nature of apartheid in which people were forcibly located onto former tribal lands, called Bantustans. Tourism is one of the few business opportunities providing employment along the former Transkei coast. The tourism industry has been identified by many worldwide as a key strategy that can lead to economic upliftment, community development and poverty relief in the developing world. The predicament however, lies in the challenge of accepting or managing the negative consequences of tourism for the potential long term benefits offered by tourism-led development. Tourism development theory reflects development theory from traditional, top-down economic-growth based models to a more wide based approach with an emphasis on bottom-up planning, meeting of basic human need and a focus on sustainable development. Consequentially new and alternative forms of tourism have emerged and can be viewed as a response to some of the negative consequences of the mass tourism-led model of economic development. Backpacker tourism is one niche of the tourism market that is providing positive local socioeconomic benefits. This thesis is presented as a case study of Mdumbi Backpackers on the former Transkei coast. Mdumbi Backpackers is a unique example of a model of tourism that is providing meaningful benefits to the people who live in this community. By going one step further with the creation of the non-profit organisation Transcape, their involvement in the community has grown significantly, encouraging positive and sustainable development in the areas of social development, education and health. Mdumbi Backpackers goes beyond the notions of locally owned and sustainable approaches and actively encourages development by setting up community organisations and initiatives in a sustainable and equitable way. This approach to tourism-led development is well suited for the needs and objectives of the community as well preserving the natural environment. This thesis presents an exemplary example from which lessons can be learned and applied to developing tourism in a sustainable and equitable way in other rural communities.
- Full Text:
- Authors: Hitchcock, Kelly Alexandra
- Date: 2014
- Subjects: Mdumbi Backpackers -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape , Tourism -- South Africa -- Eastern Cape -- Planning , Backpacking -- South Africa -- Eastern Cape -- Case studies , Black people -- Employment -- South Africa -- Eastern Cape , Sustainable development -- South Africa -- Eastern Cape , Economic development -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3377 , http://hdl.handle.net/10962/d1013143
- Description: The former Transkei region of the Eastern Cape of South Africa, in common with many of the other former Bantustans, is currently facing a developmental backlog. It is one of the poorest regions of the country and is a direct product of South Africa’s history of colonisation and geopolitical nature of apartheid in which people were forcibly located onto former tribal lands, called Bantustans. Tourism is one of the few business opportunities providing employment along the former Transkei coast. The tourism industry has been identified by many worldwide as a key strategy that can lead to economic upliftment, community development and poverty relief in the developing world. The predicament however, lies in the challenge of accepting or managing the negative consequences of tourism for the potential long term benefits offered by tourism-led development. Tourism development theory reflects development theory from traditional, top-down economic-growth based models to a more wide based approach with an emphasis on bottom-up planning, meeting of basic human need and a focus on sustainable development. Consequentially new and alternative forms of tourism have emerged and can be viewed as a response to some of the negative consequences of the mass tourism-led model of economic development. Backpacker tourism is one niche of the tourism market that is providing positive local socioeconomic benefits. This thesis is presented as a case study of Mdumbi Backpackers on the former Transkei coast. Mdumbi Backpackers is a unique example of a model of tourism that is providing meaningful benefits to the people who live in this community. By going one step further with the creation of the non-profit organisation Transcape, their involvement in the community has grown significantly, encouraging positive and sustainable development in the areas of social development, education and health. Mdumbi Backpackers goes beyond the notions of locally owned and sustainable approaches and actively encourages development by setting up community organisations and initiatives in a sustainable and equitable way. This approach to tourism-led development is well suited for the needs and objectives of the community as well preserving the natural environment. This thesis presents an exemplary example from which lessons can be learned and applied to developing tourism in a sustainable and equitable way in other rural communities.
- Full Text:
Toward a culture of engagement: leveraging the enterprise social network
- Authors: Alistoun, Garth
- Date: 2014
- Subjects: Communication in organizations -- South Africa Business communication -- South Africa Social media -- South Africa -- Case studies Leadership -- South Africa -- Case studies Human capital -- Management Personnel management Organizational effectiveness
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1154 , http://hdl.handle.net/10962/d1010869
- Description: This research aims to provide a theory of enterprise social networking that generates and/or sustains a culture of employee engagement within a chosen South African private sector company. Based on an extensive review of interesting literature and the application of a grounded theory process in a chosen case, this research work provides a theory of enterprise social networking sustaining and growing employee engagement together with an explanatory theoretical framework that makes the theory more practical. Employee engagement is defined as “the harnessing of organisation member’s selves to their work roles; in engagement people employ and express themselves physically, cognitively, and emotionally during role performances.” This research regards employee engagement as a three part concept composed of a trait (personality/cognitive) aspect, a state (emotional) aspect, and a behavioural aspect. Research has shown that employee engagement has an unequivocal positive impact on business outcomes, such as profitability, business performance, employee retention and productivity. Employee engagement can be regarded as a culture if it is abundant within the organization’s employee population. Gatenby et al. (2009) propose that employee engagement is fostered by creating the desire and opportunity for employees to connect with colleagues, managers and the wider organisation. This standpoint is supported by Kular et al. (2008) who state that the “key drivers of employee engagement identified include communication, opportunities for employees to feed their views upward and thinking that their managers are committed to the organisation.” Further indicators of employee engagement include strong leadership (particularly in the form of servant leadership), accountability, a positive and open organisational culture, autonomy, and opportunities for development. One of the key facets of employee engagement is connection. A complementary definition of social media, an umbrella under which enterprise social networks fall, is that “(it) is more of a relationship channel, a connection channel. Each and every tweet, update, video, post, is a connection point to another human being. And it’s the other human being who will determine your worth to them.” Social media provides participants with access to a larger pool of resources and relationships than they would normally have access to. This enlarged relationship/resource pool is a result of expanding human and social capital enabled through social media tools. In order to produce a theory of enterprise social networking sustaining and growing a culture of employee engagement a rigorous grounded theory methodology coupled with a case study methodology was applied. The case study methodology was used to identify a suitable research site and interesting participants within the site while the grounded theory process was used to produce both qualitative and quantitative data sets in a suitability rigorous fashion. The corroborative data was then used to discover and define the emergent theory.
- Full Text:
- Authors: Alistoun, Garth
- Date: 2014
- Subjects: Communication in organizations -- South Africa Business communication -- South Africa Social media -- South Africa -- Case studies Leadership -- South Africa -- Case studies Human capital -- Management Personnel management Organizational effectiveness
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1154 , http://hdl.handle.net/10962/d1010869
- Description: This research aims to provide a theory of enterprise social networking that generates and/or sustains a culture of employee engagement within a chosen South African private sector company. Based on an extensive review of interesting literature and the application of a grounded theory process in a chosen case, this research work provides a theory of enterprise social networking sustaining and growing employee engagement together with an explanatory theoretical framework that makes the theory more practical. Employee engagement is defined as “the harnessing of organisation member’s selves to their work roles; in engagement people employ and express themselves physically, cognitively, and emotionally during role performances.” This research regards employee engagement as a three part concept composed of a trait (personality/cognitive) aspect, a state (emotional) aspect, and a behavioural aspect. Research has shown that employee engagement has an unequivocal positive impact on business outcomes, such as profitability, business performance, employee retention and productivity. Employee engagement can be regarded as a culture if it is abundant within the organization’s employee population. Gatenby et al. (2009) propose that employee engagement is fostered by creating the desire and opportunity for employees to connect with colleagues, managers and the wider organisation. This standpoint is supported by Kular et al. (2008) who state that the “key drivers of employee engagement identified include communication, opportunities for employees to feed their views upward and thinking that their managers are committed to the organisation.” Further indicators of employee engagement include strong leadership (particularly in the form of servant leadership), accountability, a positive and open organisational culture, autonomy, and opportunities for development. One of the key facets of employee engagement is connection. A complementary definition of social media, an umbrella under which enterprise social networks fall, is that “(it) is more of a relationship channel, a connection channel. Each and every tweet, update, video, post, is a connection point to another human being. And it’s the other human being who will determine your worth to them.” Social media provides participants with access to a larger pool of resources and relationships than they would normally have access to. This enlarged relationship/resource pool is a result of expanding human and social capital enabled through social media tools. In order to produce a theory of enterprise social networking sustaining and growing a culture of employee engagement a rigorous grounded theory methodology coupled with a case study methodology was applied. The case study methodology was used to identify a suitable research site and interesting participants within the site while the grounded theory process was used to produce both qualitative and quantitative data sets in a suitability rigorous fashion. The corroborative data was then used to discover and define the emergent theory.
- Full Text:
Towards a platform to visualize the state of South Africa's information security
- Swart, Ignus, Irwin, Barry V W, Grobler, Marthie
- Authors: Swart, Ignus , Irwin, Barry V W , Grobler, Marthie
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429688 , vital:72632 , 10.1109/ISSA.2014.6950511
- Description: Attacks via the Internet infrastructure is increasingly becoming a daily occurrence and South Africa is no exception. In response, certain governments have published strategies pertaining to information security on a national level. These policies aim to ensure that critical infrastructure is protected, and that there is a move towards a greater state of information security readiness. This is also the case for South Africa where a variety of policy initiatives have started to gain momentum. While establishing strategy and policy is essential, ensuring its implementation is often difficult and dependent on the availability of resources. This is even more so in the case of information security since virtually all standardized security improvement processes start off with specifying that a proper inventory is required of all hardware, software, people and processes. While this may be possible to achieve at an organizational level, it is far more challenging on a national level. In this paper, the authors examine the possibility of making use of available data sources to achieve inventory of infrastructure on a national level and to visualize the state of a country's information security in at least a partial manner.
- Full Text:
- Authors: Swart, Ignus , Irwin, Barry V W , Grobler, Marthie
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429688 , vital:72632 , 10.1109/ISSA.2014.6950511
- Description: Attacks via the Internet infrastructure is increasingly becoming a daily occurrence and South Africa is no exception. In response, certain governments have published strategies pertaining to information security on a national level. These policies aim to ensure that critical infrastructure is protected, and that there is a move towards a greater state of information security readiness. This is also the case for South Africa where a variety of policy initiatives have started to gain momentum. While establishing strategy and policy is essential, ensuring its implementation is often difficult and dependent on the availability of resources. This is even more so in the case of information security since virtually all standardized security improvement processes start off with specifying that a proper inventory is required of all hardware, software, people and processes. While this may be possible to achieve at an organizational level, it is far more challenging on a national level. In this paper, the authors examine the possibility of making use of available data sources to achieve inventory of infrastructure on a national level and to visualize the state of a country's information security in at least a partial manner.
- Full Text: