Application of Baylis-Hillman methodology in the construction of complex heterocyclic targets
- Ganto, Mlungiseleli MacDonald
- Authors: Ganto, Mlungiseleli MacDonald
- Date: 2009
- Subjects: Heterocyclic compounds -- Derivatives Heterocyclic chemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4401 , http://hdl.handle.net/10962/d1006703
- Description: Baylis-Hillman reactions using various aromatic aldehydes, activated alkenes and catalysts have been used to: - access an extensive range of poly-heterocyclic products;explore chemoselectivity; and optimise reaction efficiency. Chromone-3-carbaldehydes and chromone-2-carbaldehydes, prepared via Vielsmeier-Haack and Kostanecki-Robinson methodology, respectively, have been used as Baylis-Hillman substrates with four different catalysts, viz., 1,4-diazabicyclo[2.2.2]octane (DABCO), 3-hydroxyquinuclidine (3-HQ), imidazole and N’,N’,N’,N’- tetramethylpropanediamine (TMPDA), and with methyl vinyl ketone (MVK), methyl acrylate, cyclic enones (2-cyclohexen-1-one, 2-cyclopenten-1-one and chromones) as activated alkenes. Reactions of the chromone- -carbaldehydes with MVK afforded dimeric Baylis-Hillman adducts when catalyzed by DABCO but when the same reactions were repeated using 3-HQ as catalyst, the dimeric products were accompanied by tricyclic Baylis-Hillman adducts. Use of excess MVK, however, led to mixtures of the normal Baylis-Hillman adducts and the tricyclic adducts – interestingly, with the apparent absence of the dimeric products. While reactions of chromone-3-carbaldehydes with methyl acrylate afforded the normal Baylis-Hillman adducts, the chromone-2- carbaldehydes produced, instead, rearrangement products, consistent with an earlier, single observation. Reactions of 2-nitrobenzaldehydes with cyclic enones using imidazole as catalyst afforded the normal Baylis-Hillman adducts, reductive cyclisation of the 2-cyclohexen-1- one and 2-cyclopenten-1-one adducts, using acetic acid and iron powder, afforded the corresponding quinoline erivatives. Treatment of cyclic enones with pyridine-2-carbaldehydes and quinoline-2-carbaldehydes using TMPDA as catalyst generally gave the expected Baylis-Hillman adducts. However, indolizine derivatives were isolated directly from Baylis-Hillman reactions involving pyridine-2-carbaldehydes and 2-cyclohexen-1-one. The remaining Baylis-Hillman adducts were cyclized to the corresponding indolizines by treatment with acetic anhydride both under reflux and under microwave-assisted conditions, the latter approach providing remarkably rapid and efficient access to the polycyclic products. Computer modelling studies have been conducted on selected polycyclic products at the Molecular Mechanics (MM), Quantum Mechanical (QM) and Density Functional (DFT) levels. The theoretical results have been used to calculate UV, IR and NMR absorption data, which have been compared, in turn, with the experimental spectroscopic data. Use has also been made of the estreNova NMR prediction programme and, generally, good agreement has been observed between the predicted and experimental spectroscopic data.
- Full Text:
- Authors: Ganto, Mlungiseleli MacDonald
- Date: 2009
- Subjects: Heterocyclic compounds -- Derivatives Heterocyclic chemistry
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4401 , http://hdl.handle.net/10962/d1006703
- Description: Baylis-Hillman reactions using various aromatic aldehydes, activated alkenes and catalysts have been used to: - access an extensive range of poly-heterocyclic products;explore chemoselectivity; and optimise reaction efficiency. Chromone-3-carbaldehydes and chromone-2-carbaldehydes, prepared via Vielsmeier-Haack and Kostanecki-Robinson methodology, respectively, have been used as Baylis-Hillman substrates with four different catalysts, viz., 1,4-diazabicyclo[2.2.2]octane (DABCO), 3-hydroxyquinuclidine (3-HQ), imidazole and N’,N’,N’,N’- tetramethylpropanediamine (TMPDA), and with methyl vinyl ketone (MVK), methyl acrylate, cyclic enones (2-cyclohexen-1-one, 2-cyclopenten-1-one and chromones) as activated alkenes. Reactions of the chromone- -carbaldehydes with MVK afforded dimeric Baylis-Hillman adducts when catalyzed by DABCO but when the same reactions were repeated using 3-HQ as catalyst, the dimeric products were accompanied by tricyclic Baylis-Hillman adducts. Use of excess MVK, however, led to mixtures of the normal Baylis-Hillman adducts and the tricyclic adducts – interestingly, with the apparent absence of the dimeric products. While reactions of chromone-3-carbaldehydes with methyl acrylate afforded the normal Baylis-Hillman adducts, the chromone-2- carbaldehydes produced, instead, rearrangement products, consistent with an earlier, single observation. Reactions of 2-nitrobenzaldehydes with cyclic enones using imidazole as catalyst afforded the normal Baylis-Hillman adducts, reductive cyclisation of the 2-cyclohexen-1- one and 2-cyclopenten-1-one adducts, using acetic acid and iron powder, afforded the corresponding quinoline erivatives. Treatment of cyclic enones with pyridine-2-carbaldehydes and quinoline-2-carbaldehydes using TMPDA as catalyst generally gave the expected Baylis-Hillman adducts. However, indolizine derivatives were isolated directly from Baylis-Hillman reactions involving pyridine-2-carbaldehydes and 2-cyclohexen-1-one. The remaining Baylis-Hillman adducts were cyclized to the corresponding indolizines by treatment with acetic anhydride both under reflux and under microwave-assisted conditions, the latter approach providing remarkably rapid and efficient access to the polycyclic products. Computer modelling studies have been conducted on selected polycyclic products at the Molecular Mechanics (MM), Quantum Mechanical (QM) and Density Functional (DFT) levels. The theoretical results have been used to calculate UV, IR and NMR absorption data, which have been compared, in turn, with the experimental spectroscopic data. Use has also been made of the estreNova NMR prediction programme and, generally, good agreement has been observed between the predicted and experimental spectroscopic data.
- Full Text:
Application of neural networks to South African GPS TEC modelling
- Habarulema, John B, McKinnell, Lee-Anne, Cilliers, Pierre J, Opperman, Ben D L
- Authors: Habarulema, John B , McKinnell, Lee-Anne , Cilliers, Pierre J , Opperman, Ben D L
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6807 , http://hdl.handle.net/10962/d1004193 , http://dx.doi.org/10.1016/j.asr.2008.08.020
- Description: The propagation of radio signals in the Earth’s atmosphere is dominantly affected by the ionosphere due to its dispersive nature. Global Positioning System (GPS) data provides relevant information that leads to the derivation of total electron content (TEC) which can be considered as the ionosphere’s measure of ionisation. This paper presents part of a feasibility study for the development of a Neural Network (NN) based model for the prediction of South African GPS derived TEC. The South African GPS receiver network is operated and maintained by the Chief Directorate Surveys and Mapping (CDSM) in Cape Town, South Africa. Vertical total electron content (VTEC) was calculated for four GPS receiver stations using the Adjusted Spherical Harmonic (ASHA) model. Factors that influence TEC were then identified and used to derive input parameters for the NN. The well established factors used are seasonal variation, diurnal variation, solar activity and magnetic activity. Comparison of diurnal predicted TEC values from both the NN model and the International Reference Ionosphere (IRI-2001) with GPS TEC revealed that the IRI provides more accurate predictions than the NN model during the spring equinoxes. However, on average the NN model predicts GPS TEC more accurately than the IRI model over the GPS locations considered within South Africa.
- Full Text:
- Authors: Habarulema, John B , McKinnell, Lee-Anne , Cilliers, Pierre J , Opperman, Ben D L
- Date: 2009
- Language: English
- Type: Article
- Identifier: vital:6807 , http://hdl.handle.net/10962/d1004193 , http://dx.doi.org/10.1016/j.asr.2008.08.020
- Description: The propagation of radio signals in the Earth’s atmosphere is dominantly affected by the ionosphere due to its dispersive nature. Global Positioning System (GPS) data provides relevant information that leads to the derivation of total electron content (TEC) which can be considered as the ionosphere’s measure of ionisation. This paper presents part of a feasibility study for the development of a Neural Network (NN) based model for the prediction of South African GPS derived TEC. The South African GPS receiver network is operated and maintained by the Chief Directorate Surveys and Mapping (CDSM) in Cape Town, South Africa. Vertical total electron content (VTEC) was calculated for four GPS receiver stations using the Adjusted Spherical Harmonic (ASHA) model. Factors that influence TEC were then identified and used to derive input parameters for the NN. The well established factors used are seasonal variation, diurnal variation, solar activity and magnetic activity. Comparison of diurnal predicted TEC values from both the NN model and the International Reference Ionosphere (IRI-2001) with GPS TEC revealed that the IRI provides more accurate predictions than the NN model during the spring equinoxes. However, on average the NN model predicts GPS TEC more accurately than the IRI model over the GPS locations considered within South Africa.
- Full Text:
Archetypal hero or living saint? The veneration of Nelson Mandela
- Authors: Maylam, Paul
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450030 , vital:74877 , https://www.scielo.org.za/pdf/hist/v54n2/04.pdf
- Description: It is now a commonplace that Nelson Mandela–Madiba–has become the most venerated, iconic political figure of the late twentieth and early twenty-first century. Accolades and awards have been heaped upon him. In the words of Kofi Annan, the former UN Secretary-General,“To this day, Madiba remains probably the single most admired, most respected international figure in the entire world”. 1 “In these times of global warfare and strife,” remarks Desmond Tutu,“… Nelson Mandela stands out as a global icon for peace, love, reconciliation and magnanimity.” 2 In the international media, Mandela has been variously described as the only living saint, 3 and as “a moral colossus” towering over the world. 4 Nadine Gordimer views Gandhi and Mandela as “the two indisputably magnificent great people of the last millennium.” 5 The former Mayor of London, Ken Livingstone, was determined, when still in office, that a statue of Mandela be built in Trafalgar Square “so Nelson on his column and Nelson Mandela on his pedestal would in a sense encapsulate the beginning and the end of the British Empire.” 6 There are actual plans afoot to construct a massive statue of Mandela, along the lines of the Statue of Liberty, overlooking the harbour in Port Elizabeth.
- Full Text:
- Authors: Maylam, Paul
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/450030 , vital:74877 , https://www.scielo.org.za/pdf/hist/v54n2/04.pdf
- Description: It is now a commonplace that Nelson Mandela–Madiba–has become the most venerated, iconic political figure of the late twentieth and early twenty-first century. Accolades and awards have been heaped upon him. In the words of Kofi Annan, the former UN Secretary-General,“To this day, Madiba remains probably the single most admired, most respected international figure in the entire world”. 1 “In these times of global warfare and strife,” remarks Desmond Tutu,“… Nelson Mandela stands out as a global icon for peace, love, reconciliation and magnanimity.” 2 In the international media, Mandela has been variously described as the only living saint, 3 and as “a moral colossus” towering over the world. 4 Nadine Gordimer views Gandhi and Mandela as “the two indisputably magnificent great people of the last millennium.” 5 The former Mayor of London, Ken Livingstone, was determined, when still in office, that a statue of Mandela be built in Trafalgar Square “so Nelson on his column and Nelson Mandela on his pedestal would in a sense encapsulate the beginning and the end of the British Empire.” 6 There are actual plans afoot to construct a massive statue of Mandela, along the lines of the Statue of Liberty, overlooking the harbour in Port Elizabeth.
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Arguing from identity: ontology to advocacy in Charles Taylor's political thought
- Authors: Sadian, Samuel Dominic
- Date: 2009
- Subjects: Taylor, Charles, 1931- -- Political and social views Taylor, Charles, 1931- -- Criticism and interpretation Cultural pluralism Political culture Identity (Philosophical concept) Ontology
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2829 , http://hdl.handle.net/10962/d1003039
- Description: In this thesis I discuss three normative claims that I take to be central elements of Charles Taylor’s political thought. The first of these is Taylor’s contention that, in contemporary pluralistic societies, justifying socially prevailing norms by appealing to universally binding moral values is unlikely to promote social solidarity. Because this approach tends to downplay the goods that people realise through membership in particular associations, Taylor believes we must adopt a model of justification that does not prioritise universal over particular goods if we are to further social co-operation. A second claim Taylor defends is that commitment to the liberal value of collective self-rule implies treating patriotically motivated public service as a non-instrumental good. We should not, Taylor argues, regard collective association as nothing more than a means to satisfying private goals. Taylor advances a third claim, that is, he maintains that liberal toleration for diverse ways of life may require a perfectionist state that supports particularistic ways of life when they are threatened by decline. I offer a qualified defence of the first two claims, but suggest that the third is less compelling. I attempt to do this by evaluating Taylor’s claims against the standards of lucid argumentation that he himself lays down. In discussing social and political norms, which he describes as “advocacy” issues, Taylor argues that our normative commitments necessarily rely on an underlying social ontology. More specifically, Taylor argues that the political values we defend are those that enable us to secure the interests we have as the bearers of an identity possessing both individual and collective dimensions. In setting out the conditions that favour integrated and free identity formation we may thereby reach a clearer understanding of the political norms that we wish to endorse. I argue that, while Taylor’s ontological reflections might well incline us to accept his model of justification and his account of patriotic social commitment, they do not of themselves dispose us to accept state perfectionism.
- Full Text:
- Authors: Sadian, Samuel Dominic
- Date: 2009
- Subjects: Taylor, Charles, 1931- -- Political and social views Taylor, Charles, 1931- -- Criticism and interpretation Cultural pluralism Political culture Identity (Philosophical concept) Ontology
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2829 , http://hdl.handle.net/10962/d1003039
- Description: In this thesis I discuss three normative claims that I take to be central elements of Charles Taylor’s political thought. The first of these is Taylor’s contention that, in contemporary pluralistic societies, justifying socially prevailing norms by appealing to universally binding moral values is unlikely to promote social solidarity. Because this approach tends to downplay the goods that people realise through membership in particular associations, Taylor believes we must adopt a model of justification that does not prioritise universal over particular goods if we are to further social co-operation. A second claim Taylor defends is that commitment to the liberal value of collective self-rule implies treating patriotically motivated public service as a non-instrumental good. We should not, Taylor argues, regard collective association as nothing more than a means to satisfying private goals. Taylor advances a third claim, that is, he maintains that liberal toleration for diverse ways of life may require a perfectionist state that supports particularistic ways of life when they are threatened by decline. I offer a qualified defence of the first two claims, but suggest that the third is less compelling. I attempt to do this by evaluating Taylor’s claims against the standards of lucid argumentation that he himself lays down. In discussing social and political norms, which he describes as “advocacy” issues, Taylor argues that our normative commitments necessarily rely on an underlying social ontology. More specifically, Taylor argues that the political values we defend are those that enable us to secure the interests we have as the bearers of an identity possessing both individual and collective dimensions. In setting out the conditions that favour integrated and free identity formation we may thereby reach a clearer understanding of the political norms that we wish to endorse. I argue that, while Taylor’s ontological reflections might well incline us to accept his model of justification and his account of patriotic social commitment, they do not of themselves dispose us to accept state perfectionism.
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Arthropod Fauna of the UAE, Vol. 2, A. van Harten (Ed.): book review
- Authors: Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451625 , vital:75065 , https://hdl.handle.net/10520/EJC32810
- Description: This volume extends the UAE's catalogue of arthropods from 1400 species to 1790 species, and describes 83 new species, four new genera and even a new tribe. The chapters include about two arachnid taxa (pseudoscorpions and cunaxid mites), and cover a total of 63 families, 26 of them previously not recorded from the country. Three chapters deal with entomobryomorph springtails, earwigs and barklice, respectively, and the rest are focused on families in the 'megadiverse' orders Coleoptera, Hymenoptera, Lepidoptera and Diptera.
- Full Text:
- Authors: Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451625 , vital:75065 , https://hdl.handle.net/10520/EJC32810
- Description: This volume extends the UAE's catalogue of arthropods from 1400 species to 1790 species, and describes 83 new species, four new genera and even a new tribe. The chapters include about two arachnid taxa (pseudoscorpions and cunaxid mites), and cover a total of 63 families, 26 of them previously not recorded from the country. Three chapters deal with entomobryomorph springtails, earwigs and barklice, respectively, and the rest are focused on families in the 'megadiverse' orders Coleoptera, Hymenoptera, Lepidoptera and Diptera.
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As safe as houses, not: The global financial crisis
- Authors: Rumney, Reg
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454203 , vital:75327 , https://hdl.handle.net/10520/EJC139943
- Description: Property journalism helped foster an unshakeable, irrational and ultimately incorrect faith in the ever-increasing value of homes, undoubtedly one of the precipitators of the global financial crisis, writes Reg Rumney.
- Full Text:
- Authors: Rumney, Reg
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454203 , vital:75327 , https://hdl.handle.net/10520/EJC139943
- Description: Property journalism helped foster an unshakeable, irrational and ultimately incorrect faith in the ever-increasing value of homes, undoubtedly one of the precipitators of the global financial crisis, writes Reg Rumney.
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Aspects of memory in the sculptural work of Jane Alexander 1982-2009
- Authors: Nicol, Tracy-Lee
- Date: 2009
- Subjects: Alexander, Jane, 1959- Collective memory -- South Africa Memory in art Women artists -- South Africa Art, African -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2417 , http://hdl.handle.net/10962/d1002213
- Description: Over three decades of research has shown that memories have significant effect on the behaviour, attitudes, beliefs, and identities of individuals and collectives, revealing also how experiences of trauma and acts of narrativisation have pertinence to the ways in which memories are stored and reconstructed. In this thesis a link is developed between memory, trauma, narrativisation processes and the interpretation of works by Jane Alexander, a contemporary artist whose work is informed by observations about South African life. Alexander’s sculptures are revealed to be not only important vessels of collective memories and experiences, but also evocations of individuals’ countermemories and traumas that remain unarticulated and invisible. Through an exploration of the workings of memory and its relation to her art, it is revealed how the past continues to exert its influence on many of South Africa’s present sociopolitical concerns and interpersonal dynamics. Indeed constantly changing memories have a significant effect on future generations’ perceptions of, and connectedness to, the past. While theories about memory have been deployed in Art History as well as the Humanities in general, Alexander’s work has not previously been considered in light of the influence of these ideas. This thesis thus contributes a new dimension to literature on the artist.
- Full Text:
- Authors: Nicol, Tracy-Lee
- Date: 2009
- Subjects: Alexander, Jane, 1959- Collective memory -- South Africa Memory in art Women artists -- South Africa Art, African -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2417 , http://hdl.handle.net/10962/d1002213
- Description: Over three decades of research has shown that memories have significant effect on the behaviour, attitudes, beliefs, and identities of individuals and collectives, revealing also how experiences of trauma and acts of narrativisation have pertinence to the ways in which memories are stored and reconstructed. In this thesis a link is developed between memory, trauma, narrativisation processes and the interpretation of works by Jane Alexander, a contemporary artist whose work is informed by observations about South African life. Alexander’s sculptures are revealed to be not only important vessels of collective memories and experiences, but also evocations of individuals’ countermemories and traumas that remain unarticulated and invisible. Through an exploration of the workings of memory and its relation to her art, it is revealed how the past continues to exert its influence on many of South Africa’s present sociopolitical concerns and interpersonal dynamics. Indeed constantly changing memories have a significant effect on future generations’ perceptions of, and connectedness to, the past. While theories about memory have been deployed in Art History as well as the Humanities in general, Alexander’s work has not previously been considered in light of the influence of these ideas. This thesis thus contributes a new dimension to literature on the artist.
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Aspects of the ecology and biology of the isopod, Exosphaeroma hylocoetes, (Barnard, 1940) in three temporarily open/closed southern African estuaries
- Authors: Henninger, Tony Oskar
- Date: 2009
- Subjects: Estuaries -- South Africa -- Eastern Cape Estuarine ecology -- South Africa -- Eastern Cape Isopoda -- South Africa -- Eastern Cape Estuarine biology -- South Africa -- Eastern Cape Ruppia maritima
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5640 , http://hdl.handle.net/10962/d1005322
- Description: Temporarily open/closed estuaries (TOCE’s) are the numerically dominant type of estuary accounting for ≈ 70 % of all estuaries along the South African coastline. Despite their numerical dominance, aspects of the biology of organisms within these systems, particularly macrocrustacea remain poorly understood. This study firstly assessed the abundance and biomass of the most common isopod, Exosphaeroma hylocoetes, in three Eastern Cape TOCE’s, (the West Kleinemonde, East Kleinemonde and Kasouga Estuaries), and their response to mouth breaching events. This study was followed by aspects of the biology of the isopod including their utilisation of submerged macrophytes as a refuge from predation and/or possible food source, as well as the growth rates of the isopods in the laboratory under different environmental conditions. Mean isopod abundances and biomasses ranged between 0 and 4 791 ind. m⁻² and 0 and 9.65 mg dwt. m⁻² in the West Kleinemonde Estuary and between 0 and 108 ind. m⁻² and 0 and 0.318 mg dwt. m⁻² in the nearby East Kleinemonde Estuary. In the Kasouga Estuary, the values ranged between 0 and 3 650 ind. m⁻² and 0 and 5.105 mg dwt. m⁻². Temporal and spatial changes in the abundance and biomass of E. hylocoetes within the three systems was primarily linked to mouth phase, with populations declining when the mouth was open and to a lesser extent, seasonality. In all three estuaries maximum isopod abundances and biomasses were recorded in their middle and upper reaches, which could be ascribed to the presence of submerged macrophytes particularly Ruppia maritima, in two of the estuaries. Males (5.71 ± 0.41 mm) were significantly larger than females (3.99 ± 0.26 mm), but the sex ratios were skewed in favour of females, (a common feature in many isopod populations). Females were found carrying brood throughout the study, releasing offspring directly into the water column, to allow recruitment to the populations. The larger the female, the larger the brood carried (up to a maximum of 72 embryo/mancas). Results of laboratory experiments indicate that the close association of Exosphaeroma hylocoetes with submerged macrophytes is a result of the plant stands providing a refuge against predation by selected ichthyofauna. However stable carbon isotope and fatty acid analyses indicate that E. hylocoetes made use of ephiphytic algae and detritus on the stems of R. maritima, rather than the submerged macrophyte itself. There were no significant differences in the growth rates of male and female isopods at combinations of temperature (15 and 25 °C) and salinity (15 and 35 ‰). Laboratory growth studies revealed that males lived longer than females (25.77 ± 3.40 weeks vs 21.52 ± 3.00 weeks), and therefore achieved larger overall size. Females, however, reached sexual maturity (at 2.5 mm) at a faster rate (two to four weeks) than males (5.5 mm after 6.5 to 11 weeks), dependent on temperature. Exosphaeroma hylocoetes with its association with submerged macrophytes, early maturity, its growth rates and longevity, female-biased sex ratios and year-round breeding, all contribute to its success in temporary open/closed estuaries.
- Full Text:
- Authors: Henninger, Tony Oskar
- Date: 2009
- Subjects: Estuaries -- South Africa -- Eastern Cape Estuarine ecology -- South Africa -- Eastern Cape Isopoda -- South Africa -- Eastern Cape Estuarine biology -- South Africa -- Eastern Cape Ruppia maritima
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5640 , http://hdl.handle.net/10962/d1005322
- Description: Temporarily open/closed estuaries (TOCE’s) are the numerically dominant type of estuary accounting for ≈ 70 % of all estuaries along the South African coastline. Despite their numerical dominance, aspects of the biology of organisms within these systems, particularly macrocrustacea remain poorly understood. This study firstly assessed the abundance and biomass of the most common isopod, Exosphaeroma hylocoetes, in three Eastern Cape TOCE’s, (the West Kleinemonde, East Kleinemonde and Kasouga Estuaries), and their response to mouth breaching events. This study was followed by aspects of the biology of the isopod including their utilisation of submerged macrophytes as a refuge from predation and/or possible food source, as well as the growth rates of the isopods in the laboratory under different environmental conditions. Mean isopod abundances and biomasses ranged between 0 and 4 791 ind. m⁻² and 0 and 9.65 mg dwt. m⁻² in the West Kleinemonde Estuary and between 0 and 108 ind. m⁻² and 0 and 0.318 mg dwt. m⁻² in the nearby East Kleinemonde Estuary. In the Kasouga Estuary, the values ranged between 0 and 3 650 ind. m⁻² and 0 and 5.105 mg dwt. m⁻². Temporal and spatial changes in the abundance and biomass of E. hylocoetes within the three systems was primarily linked to mouth phase, with populations declining when the mouth was open and to a lesser extent, seasonality. In all three estuaries maximum isopod abundances and biomasses were recorded in their middle and upper reaches, which could be ascribed to the presence of submerged macrophytes particularly Ruppia maritima, in two of the estuaries. Males (5.71 ± 0.41 mm) were significantly larger than females (3.99 ± 0.26 mm), but the sex ratios were skewed in favour of females, (a common feature in many isopod populations). Females were found carrying brood throughout the study, releasing offspring directly into the water column, to allow recruitment to the populations. The larger the female, the larger the brood carried (up to a maximum of 72 embryo/mancas). Results of laboratory experiments indicate that the close association of Exosphaeroma hylocoetes with submerged macrophytes is a result of the plant stands providing a refuge against predation by selected ichthyofauna. However stable carbon isotope and fatty acid analyses indicate that E. hylocoetes made use of ephiphytic algae and detritus on the stems of R. maritima, rather than the submerged macrophyte itself. There were no significant differences in the growth rates of male and female isopods at combinations of temperature (15 and 25 °C) and salinity (15 and 35 ‰). Laboratory growth studies revealed that males lived longer than females (25.77 ± 3.40 weeks vs 21.52 ± 3.00 weeks), and therefore achieved larger overall size. Females, however, reached sexual maturity (at 2.5 mm) at a faster rate (two to four weeks) than males (5.5 mm after 6.5 to 11 weeks), dependent on temperature. Exosphaeroma hylocoetes with its association with submerged macrophytes, early maturity, its growth rates and longevity, female-biased sex ratios and year-round breeding, all contribute to its success in temporary open/closed estuaries.
- Full Text:
Assessment and monitoring of land degradation using remote sensing and geographic information systems (GIS): a case study of Qoqodala within the Wit-Kei catchment in the Eastern Cape, South Africa
- Ngcofe, Luncedo Dalithemba Sanelisiwe
- Authors: Ngcofe, Luncedo Dalithemba Sanelisiwe
- Date: 2009
- Subjects: Geographic information systems -- South Africa -- Eastern Cape , Remote sensing -- South Africa -- Eastern Cape , Land degradation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4818 , http://hdl.handle.net/10962/d1005492 , Geographic information systems -- South Africa -- Eastern Cape , Remote sensing -- South Africa -- Eastern Cape , Land degradation -- South Africa -- Eastern Cape
- Description: Land degradation is a global problem affecting many countries including South Africa. This study was conducted in order to assess and monitor the nature and extent of land degradation within Qoqodala in the Eastern Cape Province, of South Africa. The study used GIS and Remote Sensing techniques together with household interviews in determining extent, spatial characteristics and nature of land degradation within the study area. Vegetation cover and bare-ground change were the land degradation indicators assessed and monitored by this study. Through RGB band combination, Tasselled Cap Analysis and Unsupervised ISODATA classification techniques, Landsat images over the past eighteen years (1984, 1993, 1996, 2000 and 2002) have been analysed. The results showed that there is vegetation cover and bare-ground increase in the study area. The vegetation increase has been seen as a sign of land degradation increase due to the encroachment of indigenous vegetation by Euryops species (also known as Lapesi by the local community). The bare-ground land degradation indicator has also increased. The analyses of slope showed the spatial characteristics of bare-ground occurring on moderate to flat slopes while vegetation cover occurs on steep to very steep slopes. Furthermore the photographs captured during field visits show rills and gullies or dongas occurring on bare-ground. The interviewed respondents indicated that decline in food production, increase in dongas and vast increase in Euryops and a decline in grassland are the indicators of degradation that are observed in the study area. The occurrence of erosion features (rills and dongas) on bare-ground and the increase of vegetation shown by GIS and Remote Sensing techniques showed a positive correlation with field and household survey towards establishing the nature of land degradation. In this study Landsat images together with interviews proved to be a very useful tool for land degradation research. However the suggestion of a higher spatial resolution satellite image on small catchment studies is recommended
- Full Text:
- Authors: Ngcofe, Luncedo Dalithemba Sanelisiwe
- Date: 2009
- Subjects: Geographic information systems -- South Africa -- Eastern Cape , Remote sensing -- South Africa -- Eastern Cape , Land degradation -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4818 , http://hdl.handle.net/10962/d1005492 , Geographic information systems -- South Africa -- Eastern Cape , Remote sensing -- South Africa -- Eastern Cape , Land degradation -- South Africa -- Eastern Cape
- Description: Land degradation is a global problem affecting many countries including South Africa. This study was conducted in order to assess and monitor the nature and extent of land degradation within Qoqodala in the Eastern Cape Province, of South Africa. The study used GIS and Remote Sensing techniques together with household interviews in determining extent, spatial characteristics and nature of land degradation within the study area. Vegetation cover and bare-ground change were the land degradation indicators assessed and monitored by this study. Through RGB band combination, Tasselled Cap Analysis and Unsupervised ISODATA classification techniques, Landsat images over the past eighteen years (1984, 1993, 1996, 2000 and 2002) have been analysed. The results showed that there is vegetation cover and bare-ground increase in the study area. The vegetation increase has been seen as a sign of land degradation increase due to the encroachment of indigenous vegetation by Euryops species (also known as Lapesi by the local community). The bare-ground land degradation indicator has also increased. The analyses of slope showed the spatial characteristics of bare-ground occurring on moderate to flat slopes while vegetation cover occurs on steep to very steep slopes. Furthermore the photographs captured during field visits show rills and gullies or dongas occurring on bare-ground. The interviewed respondents indicated that decline in food production, increase in dongas and vast increase in Euryops and a decline in grassland are the indicators of degradation that are observed in the study area. The occurrence of erosion features (rills and dongas) on bare-ground and the increase of vegetation shown by GIS and Remote Sensing techniques showed a positive correlation with field and household survey towards establishing the nature of land degradation. In this study Landsat images together with interviews proved to be a very useful tool for land degradation research. However the suggestion of a higher spatial resolution satellite image on small catchment studies is recommended
- Full Text:
Attitudes and perceptions towards TB in Grahamstown East in a time of HIV/AIDS
- Authors: Ndoro, Tinashe T. R
- Date: 2009
- Subjects: Tuberculosis -- South Africa -- Grahamstown , AIDS (Disease) -- Social aspects -- South Africa -- Grahamstown , HIV (Viruses) -- Social aspects -- South Africa -- Grahamstown , Tuberculosis -- Social aspects -- South Africa -- Grahamstown , Tuberculosis -- Prevention -- South Africa -- Grahamstown , AIDS (Disease) -- South Africa -- Grahamstown -- Public opinion , Tuberculosis -- South Africa -- Grahamstown -- Public opinion , Health surveys -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:3030 , http://hdl.handle.net/10962/d1002539 , Tuberculosis -- South Africa -- Grahamstown , AIDS (Disease) -- Social aspects -- South Africa -- Grahamstown , HIV (Viruses) -- Social aspects -- South Africa -- Grahamstown , Tuberculosis -- Social aspects -- South Africa -- Grahamstown , Tuberculosis -- Prevention -- South Africa -- Grahamstown , AIDS (Disease) -- South Africa -- Grahamstown -- Public opinion , Tuberculosis -- South Africa -- Grahamstown -- Public opinion , Health surveys -- South Africa -- Grahamstown
- Description: Tuberculosis (TB) has become a serious South African health problem because it is the most common opportunistic disease that leads to death in people with HIV/AIDS. Due to the airborne nature of the disease it can easily be spread to anyone including healthy people. A lack of compliance to treatment by TB patients explains why prevalence rates of the disease are high and why there is an emergence of drug resistant strains such as XDR-TB and MDR-TB. Information on existing knowledge, attitudes and perceptions regarding TB can provide a crucial foundation for the development of educational programmes and interventions aimed at reducing the further spread of the disease. This study aimed at understanding the knowledge, attitudes and perceptions towards TB and relating these to the current prevalence of HIV/AIDS. A face-to-face interview survey was conducted among adult Grahamstown East residents (n=1020). The Health Belief Model (Rosenstock et al., 1994) and Bandura’s (1986) Social Cognitive Theory formed the theoretical framework of the data collection and analysis. The data generated from the field work was first descriptively analysed providing frequency tables. Thereafter cross tabulations were calculated for relevant items using independent variables, namely gender, level of education, and experience of dealing with TB. The results of the study show that, in general, knowledge concerning TB was sufficient to provide a foundation for the adoption of healthier behaviours in the female respondents. Few of the respondents reported feeling personally susceptible although the majority of the respondents acknowledged the severity of the disease. The cues to action lacked the influence to persuade people to adopt positive health related behaviours. The perceived benefits of adopting preventative behaviour were not very influential in the adoption of healthier behavioural changes in the respondents. Disease stigma regarding the dual association of TB and HIV/AIDS was the main barrier for the adoption of healthier behavioural attitudes. Perceived self-efficacy in preventative behaviours was generally low in the less educated respondents. Recommendations regarding areas for future research and change interventions are provided.
- Full Text:
- Authors: Ndoro, Tinashe T. R
- Date: 2009
- Subjects: Tuberculosis -- South Africa -- Grahamstown , AIDS (Disease) -- Social aspects -- South Africa -- Grahamstown , HIV (Viruses) -- Social aspects -- South Africa -- Grahamstown , Tuberculosis -- Social aspects -- South Africa -- Grahamstown , Tuberculosis -- Prevention -- South Africa -- Grahamstown , AIDS (Disease) -- South Africa -- Grahamstown -- Public opinion , Tuberculosis -- South Africa -- Grahamstown -- Public opinion , Health surveys -- South Africa -- Grahamstown
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:3030 , http://hdl.handle.net/10962/d1002539 , Tuberculosis -- South Africa -- Grahamstown , AIDS (Disease) -- Social aspects -- South Africa -- Grahamstown , HIV (Viruses) -- Social aspects -- South Africa -- Grahamstown , Tuberculosis -- Social aspects -- South Africa -- Grahamstown , Tuberculosis -- Prevention -- South Africa -- Grahamstown , AIDS (Disease) -- South Africa -- Grahamstown -- Public opinion , Tuberculosis -- South Africa -- Grahamstown -- Public opinion , Health surveys -- South Africa -- Grahamstown
- Description: Tuberculosis (TB) has become a serious South African health problem because it is the most common opportunistic disease that leads to death in people with HIV/AIDS. Due to the airborne nature of the disease it can easily be spread to anyone including healthy people. A lack of compliance to treatment by TB patients explains why prevalence rates of the disease are high and why there is an emergence of drug resistant strains such as XDR-TB and MDR-TB. Information on existing knowledge, attitudes and perceptions regarding TB can provide a crucial foundation for the development of educational programmes and interventions aimed at reducing the further spread of the disease. This study aimed at understanding the knowledge, attitudes and perceptions towards TB and relating these to the current prevalence of HIV/AIDS. A face-to-face interview survey was conducted among adult Grahamstown East residents (n=1020). The Health Belief Model (Rosenstock et al., 1994) and Bandura’s (1986) Social Cognitive Theory formed the theoretical framework of the data collection and analysis. The data generated from the field work was first descriptively analysed providing frequency tables. Thereafter cross tabulations were calculated for relevant items using independent variables, namely gender, level of education, and experience of dealing with TB. The results of the study show that, in general, knowledge concerning TB was sufficient to provide a foundation for the adoption of healthier behaviours in the female respondents. Few of the respondents reported feeling personally susceptible although the majority of the respondents acknowledged the severity of the disease. The cues to action lacked the influence to persuade people to adopt positive health related behaviours. The perceived benefits of adopting preventative behaviour were not very influential in the adoption of healthier behavioural changes in the respondents. Disease stigma regarding the dual association of TB and HIV/AIDS was the main barrier for the adoption of healthier behavioural attitudes. Perceived self-efficacy in preventative behaviours was generally low in the less educated respondents. Recommendations regarding areas for future research and change interventions are provided.
- Full Text:
Augmenting an e-Commerce service for Marginalized Communities: A Rewards Based Marketing Approach
- Jere, Norbert R, Thinyane, Mamello, Terzoli, Alfredo
- Authors: Jere, Norbert R , Thinyane, Mamello , Terzoli, Alfredo
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428463 , vital:72513 , https://www.researchgate.net/profile/Alfredo-Terzoli/publication/228968666_Augmenting_an_e-Com-merce_service_for_Marginalized_Communities_A_Rewards_Based_Marketing_Approach/links/09e4151344c1f615f7000000/Augmenting-an-e-Commerce-service-for-Marginalized-Communities-A-Rewards-Based-Marketing-Approach.pdf
- Description: Information and Communication technologies (ICTs) have been widely deployed in developmental programmes and this has lead to the crea-tion of a new field–ICT for development (ICT4D). Many e-Commerce platforms now exist in many rural areas in developing countries. ICT4D allows Small, Medium and Micro Enterprises (SMMEs) in rural areas to increase sales and gain the market share on the global market. Howev-er, many of these ICT4D projects in marginalized areas fail as a result of lacking the required resources to support ICTs. SMMEs in rural areas face problems in marketing their products on the global market. There-fore, ensuring sustainability of such systems in marginalized areas is important. This paper explains an e-Marketing strategy through a re-ward based negotiation application, aimed at improving the existing e-Commerce platform. The e-Commerce platform has been deployed for the Dwesa community. Dwesa is a rural area in the Eastern Cape prov-ince of South Africa.
- Full Text:
- Authors: Jere, Norbert R , Thinyane, Mamello , Terzoli, Alfredo
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428463 , vital:72513 , https://www.researchgate.net/profile/Alfredo-Terzoli/publication/228968666_Augmenting_an_e-Com-merce_service_for_Marginalized_Communities_A_Rewards_Based_Marketing_Approach/links/09e4151344c1f615f7000000/Augmenting-an-e-Commerce-service-for-Marginalized-Communities-A-Rewards-Based-Marketing-Approach.pdf
- Description: Information and Communication technologies (ICTs) have been widely deployed in developmental programmes and this has lead to the crea-tion of a new field–ICT for development (ICT4D). Many e-Commerce platforms now exist in many rural areas in developing countries. ICT4D allows Small, Medium and Micro Enterprises (SMMEs) in rural areas to increase sales and gain the market share on the global market. Howev-er, many of these ICT4D projects in marginalized areas fail as a result of lacking the required resources to support ICTs. SMMEs in rural areas face problems in marketing their products on the global market. There-fore, ensuring sustainability of such systems in marginalized areas is important. This paper explains an e-Marketing strategy through a re-ward based negotiation application, aimed at improving the existing e-Commerce platform. The e-Commerce platform has been deployed for the Dwesa community. Dwesa is a rural area in the Eastern Cape prov-ince of South Africa.
- Full Text:
Automated Firewall Rule Set Generation Through Passive Traffic Inspection
- Pranschke, Georg-Christian, Irwin, Barry V W, Barnett, Richard J
- Authors: Pranschke, Georg-Christian , Irwin, Barry V W , Barnett, Richard J
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428659 , vital:72527 , https://doi.org/10.1007/978-90-481-3660-5_56
- Description: Introducing rewalls and other choke point controls in existing networks is often problematic, because in the majority of cases there is already production tra c in place that cannot be interrupted. This often necessitates the time consuming manual analysis of network tra c in order to ensure that when a new system is installed, there is no disruption to legitimate ows. To improve upon this situation it is proposed that a system facilitating network tra c analysis and rewall rule set generation is developed.
- Full Text:
- Authors: Pranschke, Georg-Christian , Irwin, Barry V W , Barnett, Richard J
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428659 , vital:72527 , https://doi.org/10.1007/978-90-481-3660-5_56
- Description: Introducing rewalls and other choke point controls in existing networks is often problematic, because in the majority of cases there is already production tra c in place that cannot be interrupted. This often necessitates the time consuming manual analysis of network tra c in order to ensure that when a new system is installed, there is no disruption to legitimate ows. To improve upon this situation it is proposed that a system facilitating network tra c analysis and rewall rule set generation is developed.
- Full Text:
Automating the conversion of natural language fiction to multi-modal 3D animated virtual environments
- Authors: Glass, Kevin Robert
- Date: 2009
- Subjects: Virtual computer systems , Virtual storage (Computer science) , Virtual reality , Computer animation , Fiction -- Computer programs , Narration (Rhetoric) -- Computer simulation , Animation (Cinematography) , Natural language processing (Computer Science)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4632 , http://hdl.handle.net/10962/d1006518
- Description: Popular fiction books describe rich visual environments that contain characters, objects, and behaviour. This research develops automated processes for converting text sourced from fiction books into animated virtual environments and multi-modal films. This involves the analysis of unrestricted natural language fiction to identify appropriate visual descriptions, and the interpretation of the identified descriptions for constructing animated 3D virtual environments. The goal of the text analysis stage is the creation of annotated fiction text, which identifies visual descriptions in a structured manner. A hierarchical rule-based learning system is created that induces patterns from example annotations provided by a human, and uses these for the creation of additional annotations. Patterns are expressed as tree structures that abstract the input text on different levels according to structural (token, sentence) and syntactic (parts-of-speech, syntactic function) categories. Patterns are generalized using pair-wise merging, where dissimilar sub-trees are replaced with wild-cards. The result is a small set of generalized patterns that are able to create correct annotations. A set of generalized patterns represents a model of an annotator's mental process regarding a particular annotation category. Annotated text is interpreted automatically for constructing detailed scene descriptions. This includes identifying which scenes to visualize, and identifying the contents and behaviour in each scene. Entity behaviour in a 3D virtual environment is formulated using time-based constraints that are automatically derived from annotations. Constraints are expressed as non-linear symbolic functions that restrict the trajectories of a pair of entities over a continuous interval of time. Solutions to these constraints specify precise behaviour. We create an innovative quantified constraint optimizer for locating sound solutions, which uses interval arithmetic for treating time and space as contiguous quantities. This optimization method uses a technique of constraint relaxation and tightening that allows solution approximations to be located where constraint systems are inconsistent (an ability not previously explored in interval-based quantified constraint solving). 3D virtual environments are populated by automatically selecting geometric models or procedural geometry-creation methods from a library. 3D models are animated according to trajectories derived from constraint solutions. The final animated film is sequenced using a range of modalities including animated 3D graphics, textual subtitles, audio narrations, and foleys. Hierarchical rule-based learning is evaluated over a range of annotation categories. Models are induced for different categories of annotation without modifying the core learning algorithms, and these models are shown to be applicable to different types of books. Models are induced automatically with accuracies ranging between 51.4% and 90.4%, depending on the category. We show that models are refined if further examples are provided, and this supports a boot-strapping process for training the learning mechanism. The task of interpreting annotated fiction text and populating 3D virtual environments is successfully automated using our described techniques. Detailed scene descriptions are created accurately, where between 83% and 96% of the automatically generated descriptions require no manual modification (depending on the type of description). The interval-based quantified constraint optimizer fully automates the behaviour specification process. Sample animated multi-modal 3D films are created using extracts from fiction books that are unrestricted in terms of complexity or subject matter (unlike existing text-to-graphics systems). These examples demonstrate that: behaviour is visualized that corresponds to the descriptions in the original text; appropriate geometry is selected (or created) for visualizing entities in each scene; sequences of scenes are created for a film-like presentation of the story; and that multiple modalities are combined to create a coherent multi-modal representation of the fiction text. This research demonstrates that visual descriptions in fiction text can be automatically identified, and that these descriptions can be converted into corresponding animated virtual environments. Unlike existing text-to-graphics systems, we describe techniques that function over unrestricted natural language text and perform the conversion process without the need for manually constructed repositories of world knowledge. This enables the rapid production of animated 3D virtual environments, allowing the human designer to focus on creative aspects.
- Full Text:
- Authors: Glass, Kevin Robert
- Date: 2009
- Subjects: Virtual computer systems , Virtual storage (Computer science) , Virtual reality , Computer animation , Fiction -- Computer programs , Narration (Rhetoric) -- Computer simulation , Animation (Cinematography) , Natural language processing (Computer Science)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4632 , http://hdl.handle.net/10962/d1006518
- Description: Popular fiction books describe rich visual environments that contain characters, objects, and behaviour. This research develops automated processes for converting text sourced from fiction books into animated virtual environments and multi-modal films. This involves the analysis of unrestricted natural language fiction to identify appropriate visual descriptions, and the interpretation of the identified descriptions for constructing animated 3D virtual environments. The goal of the text analysis stage is the creation of annotated fiction text, which identifies visual descriptions in a structured manner. A hierarchical rule-based learning system is created that induces patterns from example annotations provided by a human, and uses these for the creation of additional annotations. Patterns are expressed as tree structures that abstract the input text on different levels according to structural (token, sentence) and syntactic (parts-of-speech, syntactic function) categories. Patterns are generalized using pair-wise merging, where dissimilar sub-trees are replaced with wild-cards. The result is a small set of generalized patterns that are able to create correct annotations. A set of generalized patterns represents a model of an annotator's mental process regarding a particular annotation category. Annotated text is interpreted automatically for constructing detailed scene descriptions. This includes identifying which scenes to visualize, and identifying the contents and behaviour in each scene. Entity behaviour in a 3D virtual environment is formulated using time-based constraints that are automatically derived from annotations. Constraints are expressed as non-linear symbolic functions that restrict the trajectories of a pair of entities over a continuous interval of time. Solutions to these constraints specify precise behaviour. We create an innovative quantified constraint optimizer for locating sound solutions, which uses interval arithmetic for treating time and space as contiguous quantities. This optimization method uses a technique of constraint relaxation and tightening that allows solution approximations to be located where constraint systems are inconsistent (an ability not previously explored in interval-based quantified constraint solving). 3D virtual environments are populated by automatically selecting geometric models or procedural geometry-creation methods from a library. 3D models are animated according to trajectories derived from constraint solutions. The final animated film is sequenced using a range of modalities including animated 3D graphics, textual subtitles, audio narrations, and foleys. Hierarchical rule-based learning is evaluated over a range of annotation categories. Models are induced for different categories of annotation without modifying the core learning algorithms, and these models are shown to be applicable to different types of books. Models are induced automatically with accuracies ranging between 51.4% and 90.4%, depending on the category. We show that models are refined if further examples are provided, and this supports a boot-strapping process for training the learning mechanism. The task of interpreting annotated fiction text and populating 3D virtual environments is successfully automated using our described techniques. Detailed scene descriptions are created accurately, where between 83% and 96% of the automatically generated descriptions require no manual modification (depending on the type of description). The interval-based quantified constraint optimizer fully automates the behaviour specification process. Sample animated multi-modal 3D films are created using extracts from fiction books that are unrestricted in terms of complexity or subject matter (unlike existing text-to-graphics systems). These examples demonstrate that: behaviour is visualized that corresponds to the descriptions in the original text; appropriate geometry is selected (or created) for visualizing entities in each scene; sequences of scenes are created for a film-like presentation of the story; and that multiple modalities are combined to create a coherent multi-modal representation of the fiction text. This research demonstrates that visual descriptions in fiction text can be automatically identified, and that these descriptions can be converted into corresponding animated virtual environments. Unlike existing text-to-graphics systems, we describe techniques that function over unrestricted natural language text and perform the conversion process without the need for manually constructed repositories of world knowledge. This enables the rapid production of animated 3D virtual environments, allowing the human designer to focus on creative aspects.
- Full Text:
Awkward working postures and precision performance as an example of the relationship between ergonomics and production quality
- Ngcamu, Nokubonga Slindele (Sma)
- Authors: Ngcamu, Nokubonga Slindele (Sma)
- Date: 2009
- Subjects: Human engineering , Posture , Posture disorders , Musculoskeletal system -- Diseases , Work -- Physiological aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5105 , http://hdl.handle.net/10962/d1005183 , Human engineering , Posture , Posture disorders , Musculoskeletal system -- Diseases , Work -- Physiological aspects
- Description: Ergonomics aims to improve worker health and enhance productivity and quality. Knowledge and practical evidence of this relationship would be instrumental for optimising organisational performance particularly in industrially developing countries where the discipline is still in its developmental stages. Therefore this thesis set out to analyse the relationship between ergonomics deficiencies and performance. A survey was first conducted to establish the severity of quality problems in the South African manufacturing industry and to determine if these were related to Ergonomic deficiencies. The results indicated that quality problems continue to plague industry, a challenge associated with huge cost implications. Furthermore organisations were not cognisant of the fact that ergonomics deficiencies such as poor workstation design and awkward or constrained working postures are a major contributing factor to poor quality and performance decrements. This demonstrates that much is yet to be done in raising awareness about the benefits of ergonomics in South Africa and other industrially developing countries. However, for this to be effective, tangible evidence of these purported benefits is required. In lieu of this, a laboratory study was then conducted to establish the relationship between awkward working postures and the performance of precision tasks. Acknowledging that the task and the worker are interrelated elements, the impact of precision task demands on the postural strain experienced by the human was also investigated. A high and low precision task quantified positional precision while a force task (combination of pushing and pulling) was utilised to assess the ability to maintain a precise force over time. These three tasks were performed in eight different postures; namely seated, standing, stooping 300 and 600, working overhead, lying supine, and twisting to either side. A combination of the tasks and postures resulted in 24 experimental conditions that were tested on forty eight healthy male and female participants. The performance related dependent variables were movement time, deviation from the centre of the target, and the trend/slope followed by the force exerted. Muscle activity of eight arm, shoulder and back muscles, iii supplemented with heart rate and local ratings of perceived exertion, were utilised to quantify the impact of the tasks and the postures on the individual. The results revealed that awkward working postures do in fact influence performance outcomes. In this regard, awkward working postures (such as overhead work and lying supine and stooping) were evidenced to significantly affect movement time, deviations from the target and the ability to maintain a constant force over time. These variables have a direct relationship with organisational priorities such as productivity and quality. Furthermore, the results indicated that high precision demands augment postural strain elicited through high muscle activity responses and may have negative implications for the precipitation of musculoskeletal disorders. Essentially, the work done on this thesis reflected the complex nature of ergonomics by drawing on both macro and micro-ergonomics approaches. In so doing, challenges perceived to be relevant to industry as reported by organisations formed the foundation for further laboratory studies. Therefore, more collaborative research and knowledge transfer between industry and ergonomics researchers is a necessity particularly in industrially developing countries where ergonomics is still in its developmental stages.
- Full Text:
- Authors: Ngcamu, Nokubonga Slindele (Sma)
- Date: 2009
- Subjects: Human engineering , Posture , Posture disorders , Musculoskeletal system -- Diseases , Work -- Physiological aspects
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5105 , http://hdl.handle.net/10962/d1005183 , Human engineering , Posture , Posture disorders , Musculoskeletal system -- Diseases , Work -- Physiological aspects
- Description: Ergonomics aims to improve worker health and enhance productivity and quality. Knowledge and practical evidence of this relationship would be instrumental for optimising organisational performance particularly in industrially developing countries where the discipline is still in its developmental stages. Therefore this thesis set out to analyse the relationship between ergonomics deficiencies and performance. A survey was first conducted to establish the severity of quality problems in the South African manufacturing industry and to determine if these were related to Ergonomic deficiencies. The results indicated that quality problems continue to plague industry, a challenge associated with huge cost implications. Furthermore organisations were not cognisant of the fact that ergonomics deficiencies such as poor workstation design and awkward or constrained working postures are a major contributing factor to poor quality and performance decrements. This demonstrates that much is yet to be done in raising awareness about the benefits of ergonomics in South Africa and other industrially developing countries. However, for this to be effective, tangible evidence of these purported benefits is required. In lieu of this, a laboratory study was then conducted to establish the relationship between awkward working postures and the performance of precision tasks. Acknowledging that the task and the worker are interrelated elements, the impact of precision task demands on the postural strain experienced by the human was also investigated. A high and low precision task quantified positional precision while a force task (combination of pushing and pulling) was utilised to assess the ability to maintain a precise force over time. These three tasks were performed in eight different postures; namely seated, standing, stooping 300 and 600, working overhead, lying supine, and twisting to either side. A combination of the tasks and postures resulted in 24 experimental conditions that were tested on forty eight healthy male and female participants. The performance related dependent variables were movement time, deviation from the centre of the target, and the trend/slope followed by the force exerted. Muscle activity of eight arm, shoulder and back muscles, iii supplemented with heart rate and local ratings of perceived exertion, were utilised to quantify the impact of the tasks and the postures on the individual. The results revealed that awkward working postures do in fact influence performance outcomes. In this regard, awkward working postures (such as overhead work and lying supine and stooping) were evidenced to significantly affect movement time, deviations from the target and the ability to maintain a constant force over time. These variables have a direct relationship with organisational priorities such as productivity and quality. Furthermore, the results indicated that high precision demands augment postural strain elicited through high muscle activity responses and may have negative implications for the precipitation of musculoskeletal disorders. Essentially, the work done on this thesis reflected the complex nature of ergonomics by drawing on both macro and micro-ergonomics approaches. In so doing, challenges perceived to be relevant to industry as reported by organisations formed the foundation for further laboratory studies. Therefore, more collaborative research and knowledge transfer between industry and ergonomics researchers is a necessity particularly in industrially developing countries where ergonomics is still in its developmental stages.
- Full Text:
Bank credit extension to the private sector and inflation in South Africa
- Authors: Dlamini, Samuel Nkosinathi
- Date: 2009
- Subjects: Bank loans -- South Africa , Inflation (Finance) -- South Africa , Money supply -- South Africa , Interest rates -- South Africa , Banks and banking -- South Africa , Foreign exchange rates -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:959 , http://hdl.handle.net/10962/d1002693 , Bank loans -- South Africa , Inflation (Finance) -- South Africa , Money supply -- South Africa , Interest rates -- South Africa , Banks and banking -- South Africa , Foreign exchange rates -- South Africa
- Description: This study investigates the contribution of bank credit extension to the private sector to inflation in South Africa, covering the period 1970:1-2006:4. The long-run impact of bank credit on inflation is investigated by means of the Johansen co integration model. The short-run ynamics of the inflation is subsequently modelled by means of the Vector Error Correction Model (VECM). Using the Johansen methodology, the study identifies two co integrating equations linking inflation and its eterminants. The results suggest that the long-run relationship between inflation and bank credit to the private sector is negative and statistically significant at 10% level. The determinants that are significant at 5% level are: money supply, real gross domestic product, the money market rate, rand/dollar exchange rate and imports. The results are consistent with previous findings. The speed of adjustment in response to deviation from the equilibrium path was found to be negative at 10.56% per quarter, which is consistent with findings by Ohnsorge and Oomes (2003) for Russia. Both the signs and the magnitude of the coefficients suggest that the co integrating vector describes a long-run inflation equation. The impulse response functions confirm the theoretical expectations except for the import prices. The most persistent and significant shocks observed are on impulse response functions of money supply and bank credit to the private sector. The variance decomposition results also suggest that inflation responds quicker to innovations from money supply and the money market rate. The overall results provide evidence that the surge in inflation is associated with an increase in money supply as well as the instability in exchange rate. The effects of exchange rate fluctuation on inflation are reflected through changes in import prices. Based on the results we conclude that an increase in bank credit during the period 1970:1-2006:4 had a negative mpact on inflation in South Africa.
- Full Text:
- Authors: Dlamini, Samuel Nkosinathi
- Date: 2009
- Subjects: Bank loans -- South Africa , Inflation (Finance) -- South Africa , Money supply -- South Africa , Interest rates -- South Africa , Banks and banking -- South Africa , Foreign exchange rates -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:959 , http://hdl.handle.net/10962/d1002693 , Bank loans -- South Africa , Inflation (Finance) -- South Africa , Money supply -- South Africa , Interest rates -- South Africa , Banks and banking -- South Africa , Foreign exchange rates -- South Africa
- Description: This study investigates the contribution of bank credit extension to the private sector to inflation in South Africa, covering the period 1970:1-2006:4. The long-run impact of bank credit on inflation is investigated by means of the Johansen co integration model. The short-run ynamics of the inflation is subsequently modelled by means of the Vector Error Correction Model (VECM). Using the Johansen methodology, the study identifies two co integrating equations linking inflation and its eterminants. The results suggest that the long-run relationship between inflation and bank credit to the private sector is negative and statistically significant at 10% level. The determinants that are significant at 5% level are: money supply, real gross domestic product, the money market rate, rand/dollar exchange rate and imports. The results are consistent with previous findings. The speed of adjustment in response to deviation from the equilibrium path was found to be negative at 10.56% per quarter, which is consistent with findings by Ohnsorge and Oomes (2003) for Russia. Both the signs and the magnitude of the coefficients suggest that the co integrating vector describes a long-run inflation equation. The impulse response functions confirm the theoretical expectations except for the import prices. The most persistent and significant shocks observed are on impulse response functions of money supply and bank credit to the private sector. The variance decomposition results also suggest that inflation responds quicker to innovations from money supply and the money market rate. The overall results provide evidence that the surge in inflation is associated with an increase in money supply as well as the instability in exchange rate. The effects of exchange rate fluctuation on inflation are reflected through changes in import prices. Based on the results we conclude that an increase in bank credit during the period 1970:1-2006:4 had a negative mpact on inflation in South Africa.
- Full Text:
Between a rock and a hard place:
- Authors: Keeton, Gavin R
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159401 , vital:40294 , https://hdl.handle.net/10520/EJC139947
- Description: Gavin Keeton takes an economist's tour of the current crisis : how did it happen and what does it mean?
- Full Text:
- Authors: Keeton, Gavin R
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159401 , vital:40294 , https://hdl.handle.net/10520/EJC139947
- Description: Gavin Keeton takes an economist's tour of the current crisis : how did it happen and what does it mean?
- Full Text:
Between self and author : an autoethnographic approach towards the crafting of reflexive compositions in post graduate drama studies
- Authors: Moyo, Awelani Lena
- Date: 2009
- Subjects: Drama -- Study and teachng (Higher) College and school drama
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2143 , http://hdl.handle.net/10962/d1002375
- Description: This thesis explores the merits of reflexivity in the processes of creating a performance and of performing research in Drama Studies. In it, I make a case for the validity of autobiographical material as an aid to generating such reflexivity. Through an autoethnographic case study of my work entitled Compositions (a series of performance projects) in which I focus on the theme of migration, I provide an indepth account of my experiences, focusing specifically on the interrelated concerns of body, space and journey in my ritualistic performance. My examination explores the dynamic effects of liminality within identity politics, through which I foreground several issues of concern which I have encountered as an emerging scholar and theatremaker working within an academic institution. I propose that the process of studying drama in a University ultimately requires one to continually negotiate a range of subject positions, whilst finding connections between these various identities that one may take up during the course of one’s studies. By developing an awareness of the overlapping of such identities and inhabiting the spaces in-between subject positions, I demonstrate how taking into account one’s personal lived experience can help illuminate one’s understanding of both the work of art and the research report, as well as the broader contexts in which such practice-based work exists. I illustrate how such an understanding has ultimately maximised the knowledge and learning that I have gathered, and has contributed to the crucial project of developing my authorial voice in writing and performance, which is central to the aims of the Master of Arts degree in Drama.
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- Authors: Moyo, Awelani Lena
- Date: 2009
- Subjects: Drama -- Study and teachng (Higher) College and school drama
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2143 , http://hdl.handle.net/10962/d1002375
- Description: This thesis explores the merits of reflexivity in the processes of creating a performance and of performing research in Drama Studies. In it, I make a case for the validity of autobiographical material as an aid to generating such reflexivity. Through an autoethnographic case study of my work entitled Compositions (a series of performance projects) in which I focus on the theme of migration, I provide an indepth account of my experiences, focusing specifically on the interrelated concerns of body, space and journey in my ritualistic performance. My examination explores the dynamic effects of liminality within identity politics, through which I foreground several issues of concern which I have encountered as an emerging scholar and theatremaker working within an academic institution. I propose that the process of studying drama in a University ultimately requires one to continually negotiate a range of subject positions, whilst finding connections between these various identities that one may take up during the course of one’s studies. By developing an awareness of the overlapping of such identities and inhabiting the spaces in-between subject positions, I demonstrate how taking into account one’s personal lived experience can help illuminate one’s understanding of both the work of art and the research report, as well as the broader contexts in which such practice-based work exists. I illustrate how such an understanding has ultimately maximised the knowledge and learning that I have gathered, and has contributed to the crucial project of developing my authorial voice in writing and performance, which is central to the aims of the Master of Arts degree in Drama.
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Beyond just research: Experiences from Southern Africa in developing social learning partnerships for resource conservation initiatives
- Shackleton, Charlie M, Cundill, Georgina, Knight, Andrew T
- Authors: Shackleton, Charlie M , Cundill, Georgina , Knight, Andrew T
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181157 , vital:43703 , xlink:href="https://doi.org/10.1111/j.1744-7429.2009.00559.x"
- Description: There is a well-acknowledged communication or knowledge gap between scientists and decision-makers. Many scientists who take on the challenge of narrowing this gap operate on the understanding that their role is to communicate their findings in a one-way flow of information: from science to decision-makers. However, to be effective scientists must engage in an ongoing social learning process with decision-makers, and regard themselves as facilitators, and also as one among many stakeholders who have valid and important ecological knowledge. The developing world poses some particular challenges in this regard, specifically in terms of the large number of local level subsistence resources users who are important de facto decision-makers. We examine four natural resource management case studies from South Africa that differ in spatial scale and complexity, ranging from a single village to a whole biome. We distil seven lessons to help guide development of social learning processes and organizations in similar situations relating to natural resource planning and management. The lessons pertain to: maintaining ‘key individuals’ within social learning processes; the role of researchers; the formulation of research questions that social learning processes require adaptive long-term funding and capacity support; that local resource users are key decision-makers in developing countries; some perspectives on knowledge; and the need to measure research success.
- Full Text:
- Authors: Shackleton, Charlie M , Cundill, Georgina , Knight, Andrew T
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181157 , vital:43703 , xlink:href="https://doi.org/10.1111/j.1744-7429.2009.00559.x"
- Description: There is a well-acknowledged communication or knowledge gap between scientists and decision-makers. Many scientists who take on the challenge of narrowing this gap operate on the understanding that their role is to communicate their findings in a one-way flow of information: from science to decision-makers. However, to be effective scientists must engage in an ongoing social learning process with decision-makers, and regard themselves as facilitators, and also as one among many stakeholders who have valid and important ecological knowledge. The developing world poses some particular challenges in this regard, specifically in terms of the large number of local level subsistence resources users who are important de facto decision-makers. We examine four natural resource management case studies from South Africa that differ in spatial scale and complexity, ranging from a single village to a whole biome. We distil seven lessons to help guide development of social learning processes and organizations in similar situations relating to natural resource planning and management. The lessons pertain to: maintaining ‘key individuals’ within social learning processes; the role of researchers; the formulation of research questions that social learning processes require adaptive long-term funding and capacity support; that local resource users are key decision-makers in developing countries; some perspectives on knowledge; and the need to measure research success.
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Bond market development in emerging economies: a case study of the Bond Exchange of South Africa (BESA)
- Authors: Hove, Tagara
- Date: 2009
- Subjects: Bond Exchange of South Africa , Bond market -- South Africa , Foreign exchange rates -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:961 , http://hdl.handle.net/10962/d1002695 , Bond Exchange of South Africa , Bond market -- South Africa , Foreign exchange rates -- South Africa
- Description: This study looks at the development of bond markets in emerging economies and focuses on the development of the Bond Exchange of South Africa (BESA). It explores the history, structure, performance and key issues related to the development of this market within the broader context of domestic, regional and global bond market development. BESA's experience provides valuable lessons for other emerging market economies also seeking to build bond markets. The sophistication of the local bond market is not enough to make it appealing to foreign borrowers. Market development demands an enabling market infrastructure and a background of macroeconomic stability, diversified market participants, deregulation of capital flows and an appropriate regulatory and supervisory environment.
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- Authors: Hove, Tagara
- Date: 2009
- Subjects: Bond Exchange of South Africa , Bond market -- South Africa , Foreign exchange rates -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:961 , http://hdl.handle.net/10962/d1002695 , Bond Exchange of South Africa , Bond market -- South Africa , Foreign exchange rates -- South Africa
- Description: This study looks at the development of bond markets in emerging economies and focuses on the development of the Bond Exchange of South Africa (BESA). It explores the history, structure, performance and key issues related to the development of this market within the broader context of domestic, regional and global bond market development. BESA's experience provides valuable lessons for other emerging market economies also seeking to build bond markets. The sophistication of the local bond market is not enough to make it appealing to foreign borrowers. Market development demands an enabling market infrastructure and a background of macroeconomic stability, diversified market participants, deregulation of capital flows and an appropriate regulatory and supervisory environment.
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Book Review : Trans : transgender life stories from South Africa, edited by Ruth Morgan, Charl Marais, and Joy R. Wellbeloved
- Authors: Morison, Tracy
- Date: 2009
- Language: English
- Type: Book review , text
- Identifier: vital:6214 , http://hdl.handle.net/10962/d1003069 , ISBN 9781920196226
- Description: ‘If you are silent about your pain, they’ll kill you and say you enjoyed it’ proclaimed author Zora Neale Hurston, writing during the US civil rights movement. Silence and pain are certainly central to the lives of many trans people. The term ‘trans’, also the book title, can be read as being inclusive of different ‘types’ of trans-identified people. The idea of transsexualism/transgenderism alone has long been unmentionable in most contexts owing to longstanding stigma and prejudice.
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- Authors: Morison, Tracy
- Date: 2009
- Language: English
- Type: Book review , text
- Identifier: vital:6214 , http://hdl.handle.net/10962/d1003069 , ISBN 9781920196226
- Description: ‘If you are silent about your pain, they’ll kill you and say you enjoyed it’ proclaimed author Zora Neale Hurston, writing during the US civil rights movement. Silence and pain are certainly central to the lives of many trans people. The term ‘trans’, also the book title, can be read as being inclusive of different ‘types’ of trans-identified people. The idea of transsexualism/transgenderism alone has long been unmentionable in most contexts owing to longstanding stigma and prejudice.
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