Critical core competencies for effective strategic leadership in project management
- Authors: Jowah, Enoch Larry
- Date: 2013
- Subjects: Leadership -- Psychological aspects , Project management , Core competencies , Leadership
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9305 , http://hdl.handle.net/10948/d1017230
- Description: Project management is undeniably the fastest growing discipline as organizations move into the euphoria of projectification of their operations. Though projects have been a part of human life since time immemorial, there is a sudden realisation of the effectiveness of the methods used in project management. The enrolment of students studying for project management in tertiary institutions has shown tremendous increase. Yet the project execution process is mired by high failure rates and absence of clarity on the necessary skills required for effective project execution. The authority-gap in project management presents political and operational conflicts, and new innovative ways of authority-gap reduction need to be identified and taught in training programs. Simultaneously there is a realisation by both academics and practitioners that there is a difference between managers and leaders. Extensive studies on leadership have not allowed for a one-stop-leadership-style to be used in leadership of any form, let alone project leadership. In fact there is no standard definition of leadership as this has been heavily contextualized and thereby disallowing the creation of a universal definition. No cast-in-stone leadership styles are known and thereby leaving the research on leadership to concentrate on critical competencies required for effective leadership of projects. This study seeks to establish the core competencies needed by the project leaders and other practitioners to reduce the failure rate and maximise the benefits currently sought after by organisations. Studies have shown that the matrix structure within which the embedded projects work is a contributing factor to the failure of projects. Because projects are executed by people, it would be the proper utilisation of people’s talents and competencies that are expected to yield favourable results. Thus, whilst the matrix structure creates the authority-gap that presents a problem for effective project execution, management-by-projects still remains the best way known to add economic value to performance and productivity. The study therefore focuses on those characteristics of project leaders that will most likely make the difference in the way people perform in the workplace. The research findings emphasised the importance of empowerment of project managers and the development of their interpersonal skills of the project leader with special emphasis on extroversion, genuineness of senior management, and the responsiveness of the project leaders as important requirements for effective authority- gap reduction. These critical competencies will therefore facilitate the project execution process and enhance the empowered project leader’s ability to reduce the high project failure rate and high cost overruns. These competencies apply specifically to the human element as it relates to the role of the project leader and the interaction with the team members, this new knowledge needs to be introduced into training programs and project practitioners.
- Full Text:
- Date Issued: 2013
- Authors: Jowah, Enoch Larry
- Date: 2013
- Subjects: Leadership -- Psychological aspects , Project management , Core competencies , Leadership
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9305 , http://hdl.handle.net/10948/d1017230
- Description: Project management is undeniably the fastest growing discipline as organizations move into the euphoria of projectification of their operations. Though projects have been a part of human life since time immemorial, there is a sudden realisation of the effectiveness of the methods used in project management. The enrolment of students studying for project management in tertiary institutions has shown tremendous increase. Yet the project execution process is mired by high failure rates and absence of clarity on the necessary skills required for effective project execution. The authority-gap in project management presents political and operational conflicts, and new innovative ways of authority-gap reduction need to be identified and taught in training programs. Simultaneously there is a realisation by both academics and practitioners that there is a difference between managers and leaders. Extensive studies on leadership have not allowed for a one-stop-leadership-style to be used in leadership of any form, let alone project leadership. In fact there is no standard definition of leadership as this has been heavily contextualized and thereby disallowing the creation of a universal definition. No cast-in-stone leadership styles are known and thereby leaving the research on leadership to concentrate on critical competencies required for effective leadership of projects. This study seeks to establish the core competencies needed by the project leaders and other practitioners to reduce the failure rate and maximise the benefits currently sought after by organisations. Studies have shown that the matrix structure within which the embedded projects work is a contributing factor to the failure of projects. Because projects are executed by people, it would be the proper utilisation of people’s talents and competencies that are expected to yield favourable results. Thus, whilst the matrix structure creates the authority-gap that presents a problem for effective project execution, management-by-projects still remains the best way known to add economic value to performance and productivity. The study therefore focuses on those characteristics of project leaders that will most likely make the difference in the way people perform in the workplace. The research findings emphasised the importance of empowerment of project managers and the development of their interpersonal skills of the project leader with special emphasis on extroversion, genuineness of senior management, and the responsiveness of the project leaders as important requirements for effective authority- gap reduction. These critical competencies will therefore facilitate the project execution process and enhance the empowered project leader’s ability to reduce the high project failure rate and high cost overruns. These competencies apply specifically to the human element as it relates to the role of the project leader and the interaction with the team members, this new knowledge needs to be introduced into training programs and project practitioners.
- Full Text:
- Date Issued: 2013
Critical factors for business success in co-operatives
- Authors: Mpongoshe, Lukhanyiso
- Date: 2013
- Subjects: Cooperative societies -- South Africa -- Nelson Mandela Bay Municipality , Success in business -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8842 , http://hdl.handle.net/10948/d1020041
- Description: Many countries that have achieved economic development have a dynamic co-operative sector which contributes substantially to the development of these economies. From a global perspective, co-operatives have been proven to be flexible in meeting a wide variety of social and economic human needs such as job creation, alleviation of poverty and building of communities. With the drive to decrease poverty in South Africa, there has been an increased interest to support co-operatives with the intention to provide employment, social development and building communities/ community care. It seems, however, that South Africa has not yet reached the same momentum in the co-operatives movement as elsewhere in the world and the economy is still characterized by a high unemployment rate and a low growth rate (Van der Walt, 2002). This study is an attempt to determine the factors for business success in co-operatives by assessing the strengths and weaknesses of co-operative businesses within the Nelson Mandela Metropolitan Municipality in the Eastern Cape. The study includes an extensive literature review on the nature and prevalence of co-operatives in South Africa where challenges faced by South African co-operatives and particularly those in the Eastern Cape Province, are indicated. It also highlights international best practice and reveals that for co-operative success, apart for functioning by the International Seven Cooperative Principles, knowledge and expertise in business management are absolutely necessary so that co-operatives can be profitable and sustainable. With this knowledge, an adapted form of the Small Enterprise Development Agency (SEDA) Small Business Assessment Tool was used to formulate the questionnaire and to review business management literature. A survey conducted involved fifty-one co-operative members on the database of the Nelson Mandela Metropolitan University Business Unit. The opinions of the respondents were compared with the guidelines provided by the literature in the study in order to identify the strengths and weaknesses of these co-operatives, which then determine the critical success factors for business success in co-operatives. The empirical results show that the co-operative members understand co-operative principles and function through them. They have a fairly general knowledge of business management. The results also show significantly positive correlations between Marketing Management, Financial Management, Operations Management, Human Resources Management and General Management, on the one hand, and the business success of co-operatives, on the other hand. This indicates that these respondents recognize the importance of these business functions in the success of their businesses. However, failures and weaknesses experienced in these areas lead to the recommendations that they need to be mentored as they cannot put this knowledge into application, and secondly, they need financial assistance and support to sustain the co-operative businesses.
- Full Text:
- Date Issued: 2013
- Authors: Mpongoshe, Lukhanyiso
- Date: 2013
- Subjects: Cooperative societies -- South Africa -- Nelson Mandela Bay Municipality , Success in business -- South Africa -- Nelson Mandela Bay Municipality
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8842 , http://hdl.handle.net/10948/d1020041
- Description: Many countries that have achieved economic development have a dynamic co-operative sector which contributes substantially to the development of these economies. From a global perspective, co-operatives have been proven to be flexible in meeting a wide variety of social and economic human needs such as job creation, alleviation of poverty and building of communities. With the drive to decrease poverty in South Africa, there has been an increased interest to support co-operatives with the intention to provide employment, social development and building communities/ community care. It seems, however, that South Africa has not yet reached the same momentum in the co-operatives movement as elsewhere in the world and the economy is still characterized by a high unemployment rate and a low growth rate (Van der Walt, 2002). This study is an attempt to determine the factors for business success in co-operatives by assessing the strengths and weaknesses of co-operative businesses within the Nelson Mandela Metropolitan Municipality in the Eastern Cape. The study includes an extensive literature review on the nature and prevalence of co-operatives in South Africa where challenges faced by South African co-operatives and particularly those in the Eastern Cape Province, are indicated. It also highlights international best practice and reveals that for co-operative success, apart for functioning by the International Seven Cooperative Principles, knowledge and expertise in business management are absolutely necessary so that co-operatives can be profitable and sustainable. With this knowledge, an adapted form of the Small Enterprise Development Agency (SEDA) Small Business Assessment Tool was used to formulate the questionnaire and to review business management literature. A survey conducted involved fifty-one co-operative members on the database of the Nelson Mandela Metropolitan University Business Unit. The opinions of the respondents were compared with the guidelines provided by the literature in the study in order to identify the strengths and weaknesses of these co-operatives, which then determine the critical success factors for business success in co-operatives. The empirical results show that the co-operative members understand co-operative principles and function through them. They have a fairly general knowledge of business management. The results also show significantly positive correlations between Marketing Management, Financial Management, Operations Management, Human Resources Management and General Management, on the one hand, and the business success of co-operatives, on the other hand. This indicates that these respondents recognize the importance of these business functions in the success of their businesses. However, failures and weaknesses experienced in these areas lead to the recommendations that they need to be mentored as they cannot put this knowledge into application, and secondly, they need financial assistance and support to sustain the co-operative businesses.
- Full Text:
- Date Issued: 2013
Critical indirect effects of climate change on sub-A ntarctic ecosystem functioning
- Allan, E Louise, Froneman, P William, Durgadoo, Jonathan V, McQuaid, Christopher D, Ansorge, Isabelle J, Richoux, Nicole B
- Authors: Allan, E Louise , Froneman, P William , Durgadoo, Jonathan V , McQuaid, Christopher D , Ansorge, Isabelle J , Richoux, Nicole B
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457934 , vital:75696 , xlink:href="https://doi.org/10.1002/ece3.678"
- Description: Sub‐Antarctic islands represent critical breeding habitats for land‐based top predators that dominate Southern Ocean food webs. Reproduction and molting incur high energetic demands that are sustained at the sub‐Antarctic Prince Edward Islands (PEIs) by both inshore (phytoplankton blooms; “island mass effect”; autochthonous) and offshore (allochthonous) productivity. As the relative contributions of these sustenance pathways are, in turn, affected by oceanographic conditions around the PEIs, we address the consequences of climatically driven changes in the physical environment on this island ecosystem. We show that there has been a measurable long‐term shift in the carbon isotope signatures of the benthos inhabiting the shallow shelf region of the PEIs, most likely reflecting a long‐term decline in enhanced phytoplankton productivity at the islands in response to a climate‐driven shift in the position of the sub‐Antarctic Front. Our results indicate that regional climate change has affected the balance between allochthonous and autochthonous productivity at the PEIs. Over the last three decades, inshore‐feeding top predators at the islands have shown a marked decrease in their population sizes. Conversely, population sizes of offshore‐feeding predators that forage over great distances from the islands have remained stable or increased, with one exception. Population decline of predators that rely heavily on organisms inhabiting the inshore region strongly suggest changes in prey availability, which are likely driven by factors such as fisheries impacts on some prey populations and shifts in competitive interactions among predators. In addition to these local factors, our analysis indicates that changes in prey availability may also result indirectly through regional climate change effects on the islands' marine ecosystem. Most importantly, our results indicate that a fundamental shift in the balance between allochthonous and autochthonous trophic pathways within this island ecosystem may be detected throughout the food web, demonstrating that the most powerful effects of climate change on marine systems may be indirect.
- Full Text:
- Date Issued: 2013
- Authors: Allan, E Louise , Froneman, P William , Durgadoo, Jonathan V , McQuaid, Christopher D , Ansorge, Isabelle J , Richoux, Nicole B
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457934 , vital:75696 , xlink:href="https://doi.org/10.1002/ece3.678"
- Description: Sub‐Antarctic islands represent critical breeding habitats for land‐based top predators that dominate Southern Ocean food webs. Reproduction and molting incur high energetic demands that are sustained at the sub‐Antarctic Prince Edward Islands (PEIs) by both inshore (phytoplankton blooms; “island mass effect”; autochthonous) and offshore (allochthonous) productivity. As the relative contributions of these sustenance pathways are, in turn, affected by oceanographic conditions around the PEIs, we address the consequences of climatically driven changes in the physical environment on this island ecosystem. We show that there has been a measurable long‐term shift in the carbon isotope signatures of the benthos inhabiting the shallow shelf region of the PEIs, most likely reflecting a long‐term decline in enhanced phytoplankton productivity at the islands in response to a climate‐driven shift in the position of the sub‐Antarctic Front. Our results indicate that regional climate change has affected the balance between allochthonous and autochthonous productivity at the PEIs. Over the last three decades, inshore‐feeding top predators at the islands have shown a marked decrease in their population sizes. Conversely, population sizes of offshore‐feeding predators that forage over great distances from the islands have remained stable or increased, with one exception. Population decline of predators that rely heavily on organisms inhabiting the inshore region strongly suggest changes in prey availability, which are likely driven by factors such as fisheries impacts on some prey populations and shifts in competitive interactions among predators. In addition to these local factors, our analysis indicates that changes in prey availability may also result indirectly through regional climate change effects on the islands' marine ecosystem. Most importantly, our results indicate that a fundamental shift in the balance between allochthonous and autochthonous trophic pathways within this island ecosystem may be detected throughout the food web, demonstrating that the most powerful effects of climate change on marine systems may be indirect.
- Full Text:
- Date Issued: 2013
Critical studies in carbon electrode materials with applications in the electroanalysis of the mycotoxin citrinin
- Authors: Niland, Michael John
- Date: 2013
- Subjects: Electrodes, Carbon , Mycotoxins
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4555 , http://hdl.handle.net/10962/d1018256
- Description: Guided by increasing legislation, the analysis of food borne toxins, including mycotoxins, seeks to address market related demands for the development of analytical systems to monitor this threat to food security and human health. This Thesis is directed at the assessment of the application of electrochemistry for direct electroanalysis and characterisation of the mycotoxin citrinin (CIT) in aqueous media as well as fundamental investigations of the surface of polished and oxidised glassy carbon electrodes (GCE). This study provides the first known account of CIT detection through electrochemical methods. Although electrochemically active, CIT current responses (Ip) were highly irreproducible at polished GCE with a coefficient of variation (C.V.) of 20.16 %. As stability of Ip across multiple electrode preparations is a key requirement in electroanalysis, investigations were directed at attaining stability in CIT Ip. Achieving stability in CIT Ip was investigated via two approaches, including: accounting for Ip variability between electrode preparations as a result of variable GCE surface conditions as a post-data-acquisition analysis and secondly, removing Ip variability through modification of GCE. Accounting for variability in Ip was investigated through the application of double layer capacitance as an indicator of the activity of an electrode, and in so doing serving as a relative mediator of Ip responses between electrodes. Application of this procedure dropped CIT C.V. to a third of starting value across polished GCE (C.V. = 7.18 %), chemically oxidised GCE (Pi-GCE, C.V = 8.47 %) and functionalised multi-walled carbon nanotube modified GCE (fMWCNT, C.V. = 25.79 %) and was effective with analysis of structurally distinct molecules, 2,4-dimethylaniline (2,4-DMA) and 1,2,4-trihydroxybenzene (Triol). Furthermore, it afforded the ability to determine discreet solution overlapping data sets of Ip. Stabilising Ip through GCE surface modification was achieved by anodic electro-oxidation of GCE and allowed for direct electroanalysis of CIT and subsequent characterisation and analysis of CIT in complex media as it reduced C.V. of CIT Ip to 0.73 %. Fundamental investigations of the electrode surface condition are described such that the source of variability could be identified and the interactions of CIT with the electrode understood. Two surface oxidation techniques were applied in modification of GCE; anodic electro-oxidation (EOx GCE) and chemical oxidation using piranha solution (Pi-GCE), analysis of which has previously not been reported. Fundamental analyses to determine surface morphology and chemistry of Pi-GCE, EOx-GCE and polished GCE were conducted using high resolution scanning electron microscopy (HRSEM), scanning electrochemical microscopy (SECM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FTIR) and via electroanalytical methods. These studies showed that both oxidation procedures introduced a variety of oxide species at GCE surface, and further that the extent of those species was similar with total % O being 27.67 % and 33.47 % at Pi-GCE and EOx-GCE respectively. Although chemically similar, each surface was morphologically distinct. Electrochemical analyses at the surfaces revealed Pi-GCE to behave more similarly to polished GCE than EOx-GCE. As CIT responses were found to be stable at EOx-GCE (C.V. = 0.73 %) as opposed to Pi-GCE (C.V. = 22.87 %), stability of CIT Ip was likely to be as a result of a physical interaction with electrode morphology rather than interaction on a chemical basis. Morphological analyses revealed polished GCE and Pi-GCE to be highly morphologically irregular at the micro-scale. Although comparatively smooth, the surface morphology of EOx-GCE does not account for the stability of Ip. This study thus proposed a theory to describe the mechanism by which the limited conductivity and porosity of EOx-GCE allow for it to provide a relatively stable surface area within the oxide layer, adjacent to the electrode surface, and thus provided a stable platform for electroanalysis. Voltammetric characterization of CIT at EOx-GCE revealed that anodic oxidation in aqueous media involved an uneven number of electrons to protons via an ECE mechanism. This was illustrated to be nt = 2e- accompanied by the transfer of 1H⁺ per molecule oxidised. A proposed reaction scheme for the initial stages of CIT oxidation was suggested to involve both hydroxyl and carboxyl moieties of the CIT molecule. CIT oxidation was shown to arise as a result of a relatively complex mass transport regime which included both adsorptive and diffusive derived Ip₁. The LOD in buffered aqueous media was found to be 16 nM, a highly competitive result in relation to chromatographic techniques. Further application of EOx-GCE in complex media illustrated that CIT associates non-specifically with the components of food samples, primarily proteins. As a result of this, extraction of CIT from such media is mandatory. Liquid-liquid extraction illustrated a recovery in CIT Ip₁ and in so doing provided a means of accurately and sensitively detecting CIT from food samples with an LOD of 20 nM. These responses were corroborated by HPLC analyses on the same extractions and illustrate the applicability of electroanalysis as an analytical technique.
- Full Text:
- Date Issued: 2013
- Authors: Niland, Michael John
- Date: 2013
- Subjects: Electrodes, Carbon , Mycotoxins
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4555 , http://hdl.handle.net/10962/d1018256
- Description: Guided by increasing legislation, the analysis of food borne toxins, including mycotoxins, seeks to address market related demands for the development of analytical systems to monitor this threat to food security and human health. This Thesis is directed at the assessment of the application of electrochemistry for direct electroanalysis and characterisation of the mycotoxin citrinin (CIT) in aqueous media as well as fundamental investigations of the surface of polished and oxidised glassy carbon electrodes (GCE). This study provides the first known account of CIT detection through electrochemical methods. Although electrochemically active, CIT current responses (Ip) were highly irreproducible at polished GCE with a coefficient of variation (C.V.) of 20.16 %. As stability of Ip across multiple electrode preparations is a key requirement in electroanalysis, investigations were directed at attaining stability in CIT Ip. Achieving stability in CIT Ip was investigated via two approaches, including: accounting for Ip variability between electrode preparations as a result of variable GCE surface conditions as a post-data-acquisition analysis and secondly, removing Ip variability through modification of GCE. Accounting for variability in Ip was investigated through the application of double layer capacitance as an indicator of the activity of an electrode, and in so doing serving as a relative mediator of Ip responses between electrodes. Application of this procedure dropped CIT C.V. to a third of starting value across polished GCE (C.V. = 7.18 %), chemically oxidised GCE (Pi-GCE, C.V = 8.47 %) and functionalised multi-walled carbon nanotube modified GCE (fMWCNT, C.V. = 25.79 %) and was effective with analysis of structurally distinct molecules, 2,4-dimethylaniline (2,4-DMA) and 1,2,4-trihydroxybenzene (Triol). Furthermore, it afforded the ability to determine discreet solution overlapping data sets of Ip. Stabilising Ip through GCE surface modification was achieved by anodic electro-oxidation of GCE and allowed for direct electroanalysis of CIT and subsequent characterisation and analysis of CIT in complex media as it reduced C.V. of CIT Ip to 0.73 %. Fundamental investigations of the electrode surface condition are described such that the source of variability could be identified and the interactions of CIT with the electrode understood. Two surface oxidation techniques were applied in modification of GCE; anodic electro-oxidation (EOx GCE) and chemical oxidation using piranha solution (Pi-GCE), analysis of which has previously not been reported. Fundamental analyses to determine surface morphology and chemistry of Pi-GCE, EOx-GCE and polished GCE were conducted using high resolution scanning electron microscopy (HRSEM), scanning electrochemical microscopy (SECM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), fourier transform infrared spectroscopy (FTIR) and via electroanalytical methods. These studies showed that both oxidation procedures introduced a variety of oxide species at GCE surface, and further that the extent of those species was similar with total % O being 27.67 % and 33.47 % at Pi-GCE and EOx-GCE respectively. Although chemically similar, each surface was morphologically distinct. Electrochemical analyses at the surfaces revealed Pi-GCE to behave more similarly to polished GCE than EOx-GCE. As CIT responses were found to be stable at EOx-GCE (C.V. = 0.73 %) as opposed to Pi-GCE (C.V. = 22.87 %), stability of CIT Ip was likely to be as a result of a physical interaction with electrode morphology rather than interaction on a chemical basis. Morphological analyses revealed polished GCE and Pi-GCE to be highly morphologically irregular at the micro-scale. Although comparatively smooth, the surface morphology of EOx-GCE does not account for the stability of Ip. This study thus proposed a theory to describe the mechanism by which the limited conductivity and porosity of EOx-GCE allow for it to provide a relatively stable surface area within the oxide layer, adjacent to the electrode surface, and thus provided a stable platform for electroanalysis. Voltammetric characterization of CIT at EOx-GCE revealed that anodic oxidation in aqueous media involved an uneven number of electrons to protons via an ECE mechanism. This was illustrated to be nt = 2e- accompanied by the transfer of 1H⁺ per molecule oxidised. A proposed reaction scheme for the initial stages of CIT oxidation was suggested to involve both hydroxyl and carboxyl moieties of the CIT molecule. CIT oxidation was shown to arise as a result of a relatively complex mass transport regime which included both adsorptive and diffusive derived Ip₁. The LOD in buffered aqueous media was found to be 16 nM, a highly competitive result in relation to chromatographic techniques. Further application of EOx-GCE in complex media illustrated that CIT associates non-specifically with the components of food samples, primarily proteins. As a result of this, extraction of CIT from such media is mandatory. Liquid-liquid extraction illustrated a recovery in CIT Ip₁ and in so doing provided a means of accurately and sensitively detecting CIT from food samples with an LOD of 20 nM. These responses were corroborated by HPLC analyses on the same extractions and illustrate the applicability of electroanalysis as an analytical technique.
- Full Text:
- Date Issued: 2013
Current and potential carbon stocks of trees in urban parking lots in towns of the Eastern Cape, South Africa
- O'Donoghue, Alexandra, Shackleton, Charlie M
- Authors: O'Donoghue, Alexandra , Shackleton, Charlie M
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181037 , vital:43689 , xlink:href="https://doi.org/10.1016/j.ufug.2013.07.001"
- Description: Greening of shopping centre parking lots is a potentially important strategy that can contribute to urban carbon mitigation efforts, improve aesthetics and the shopping experience of consumers, whilst adding to urban biodiversity. Twenty-eight shopping centre parking lots in six Eastern Cape urban centres, South Africa, were sampled to determine tree species composition, density and annual carbon sequestration potential. The best case parking lot found during the study was used as a benchmark to display the difference between current tree density and above-ground carbon stocks relative to the potential optimum. The highest tree density was 66 trees ha−1, whereas the average density across all sampled parking lots was less than half that (27.2 ± 22.6 trees ha−1). The average annual carbon sequestration potential per parking lot was 1390 ± 2503 kg ha−1. Planting density was positively related to annual sequestration rates, whilst parking lot age and the mean annual rainfall of the town had no influence. Mean tree species richness per parking lot was 2.3 ± 1.8 species, with a positive relationship to parking lot size, but not to mean annual rainfall of the site. The majority of trees (62.5%) in parking lots were alien species, although newer parking lots had significantly greater proportions of indigenous species. There was no difference in mean annual carbon sequestration rate per tree between indigenous and alien trees species. Low tree densities and small parking lot areas constrained the potential for earning carbon credits from trees in parking lots. Nonetheless, planners and designers need to be more aware of the potential contribution of trees towards urban sustainability.
- Full Text:
- Date Issued: 2013
- Authors: O'Donoghue, Alexandra , Shackleton, Charlie M
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/181037 , vital:43689 , xlink:href="https://doi.org/10.1016/j.ufug.2013.07.001"
- Description: Greening of shopping centre parking lots is a potentially important strategy that can contribute to urban carbon mitigation efforts, improve aesthetics and the shopping experience of consumers, whilst adding to urban biodiversity. Twenty-eight shopping centre parking lots in six Eastern Cape urban centres, South Africa, were sampled to determine tree species composition, density and annual carbon sequestration potential. The best case parking lot found during the study was used as a benchmark to display the difference between current tree density and above-ground carbon stocks relative to the potential optimum. The highest tree density was 66 trees ha−1, whereas the average density across all sampled parking lots was less than half that (27.2 ± 22.6 trees ha−1). The average annual carbon sequestration potential per parking lot was 1390 ± 2503 kg ha−1. Planting density was positively related to annual sequestration rates, whilst parking lot age and the mean annual rainfall of the town had no influence. Mean tree species richness per parking lot was 2.3 ± 1.8 species, with a positive relationship to parking lot size, but not to mean annual rainfall of the site. The majority of trees (62.5%) in parking lots were alien species, although newer parking lots had significantly greater proportions of indigenous species. There was no difference in mean annual carbon sequestration rate per tree between indigenous and alien trees species. Low tree densities and small parking lot areas constrained the potential for earning carbon credits from trees in parking lots. Nonetheless, planners and designers need to be more aware of the potential contribution of trees towards urban sustainability.
- Full Text:
- Date Issued: 2013
Curriculum Vitae of Prof Tebello Nyokong (OMB)
- Authors: Nyokong, Tebello
- Date: 2013
- Language: English
- Type: Article , text
- Identifier: vital:7233 , http://hdl.handle.net/10962/d1006180
- Description: Department of Science and Technology (DST) and National Research Foundation (NRF) Professor of Medicinal Chemistry and Nanotechnology and Distinguished Professor of Chemistry at Rhodes University.
- Full Text:
- Date Issued: 2013
- Authors: Nyokong, Tebello
- Date: 2013
- Language: English
- Type: Article , text
- Identifier: vital:7233 , http://hdl.handle.net/10962/d1006180
- Description: Department of Science and Technology (DST) and National Research Foundation (NRF) Professor of Medicinal Chemistry and Nanotechnology and Distinguished Professor of Chemistry at Rhodes University.
- Full Text:
- Date Issued: 2013
Customising a BBVC for Asterisk VoIP Services
- Oyedele, Y, Terzoli, Alfredo, Mufeti, K
- Authors: Oyedele, Y , Terzoli, Alfredo , Mufeti, K
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430942 , vital:72730 , https://doi.org/10.1007/978-1-4614-3558-7_62
- Description: Browser-based Voice over Internet Protocol Clients (BBVC) are used to access pre-determined VoIP services from VoIP service providers through Internet connections. For nomadic users within an organisa-tion’s Intranet, connections are made to the Internet to utilise these BBVC. An Intranet with an Asterisk Private Branch Exchange (PBX) as a VoIP provider however can be linked with any form of VoIP client to improve service accessibility for its users. This study aims to find a BBVC that can be customised to provide such accessibility within an Intranet. The study revealed that three BBVC are compatible. One of three BBVC was selected for customisation to provide nomadic acces-sibility to Asterisk. The functionality of the customised BBVC depended on the web technologies used and the available VoIP services.
- Full Text:
- Date Issued: 2013
- Authors: Oyedele, Y , Terzoli, Alfredo , Mufeti, K
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430942 , vital:72730 , https://doi.org/10.1007/978-1-4614-3558-7_62
- Description: Browser-based Voice over Internet Protocol Clients (BBVC) are used to access pre-determined VoIP services from VoIP service providers through Internet connections. For nomadic users within an organisa-tion’s Intranet, connections are made to the Internet to utilise these BBVC. An Intranet with an Asterisk Private Branch Exchange (PBX) as a VoIP provider however can be linked with any form of VoIP client to improve service accessibility for its users. This study aims to find a BBVC that can be customised to provide such accessibility within an Intranet. The study revealed that three BBVC are compatible. One of three BBVC was selected for customisation to provide nomadic acces-sibility to Asterisk. The functionality of the customised BBVC depended on the web technologies used and the available VoIP services.
- Full Text:
- Date Issued: 2013
Cytotoxicity of lapachol, β-lapachone and related synthetic 1, 4-naphthoquinones against oesophageal cancer cells:
- Sunassee, Suthananda N, Veale, Clinton G L, Shunmoogam-Gounden, Nelusha, Osoniyi, Omalaja, Hendricks, Denver T, Caira, Mino R, de la Mare, Jo-Anne, Edkins, Adrienne L, Pinto, Antônio V, da Silva Junior, Eufrânio N, Davies-Coleman, Michael T
- Authors: Sunassee, Suthananda N , Veale, Clinton G L , Shunmoogam-Gounden, Nelusha , Osoniyi, Omalaja , Hendricks, Denver T , Caira, Mino R , de la Mare, Jo-Anne , Edkins, Adrienne L , Pinto, Antônio V , da Silva Junior, Eufrânio N , Davies-Coleman, Michael T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165207 , vital:41218 , DOI: 10.1016/j.ejmech.2012.12.048
- Description: Naphthoquinones have been found to have a wide range of biological activities, including cytotoxicity to cancer cells. The secondary metabolites lapachol, α- and β-lapachone and a series of 25 related synthetic 1,4-naphthoquinones were screened against the oesophageal cancer cell line (WHCO1). Most of the compounds exhibited enhanced cytotoxicity (IC50 1.6–11.7 μM) compared to the current drug of choice cisplatin (IC50 = 16.5 μM).
- Full Text:
- Date Issued: 2013
- Authors: Sunassee, Suthananda N , Veale, Clinton G L , Shunmoogam-Gounden, Nelusha , Osoniyi, Omalaja , Hendricks, Denver T , Caira, Mino R , de la Mare, Jo-Anne , Edkins, Adrienne L , Pinto, Antônio V , da Silva Junior, Eufrânio N , Davies-Coleman, Michael T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/165207 , vital:41218 , DOI: 10.1016/j.ejmech.2012.12.048
- Description: Naphthoquinones have been found to have a wide range of biological activities, including cytotoxicity to cancer cells. The secondary metabolites lapachol, α- and β-lapachone and a series of 25 related synthetic 1,4-naphthoquinones were screened against the oesophageal cancer cell line (WHCO1). Most of the compounds exhibited enhanced cytotoxicity (IC50 1.6–11.7 μM) compared to the current drug of choice cisplatin (IC50 = 16.5 μM).
- Full Text:
- Date Issued: 2013
Dambudzo Marechera: a psychobiographical study
- Muchena, Kudakwashe Christopher
- Authors: Muchena, Kudakwashe Christopher
- Date: 2013
- Subjects: Marechera, Dambudzo, 1952-1987 , Developmental psychology , Psychology -- Biographical methods , Authors -- Biography , Authors, African -- 20th century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9964 , http://hdl.handle.net/10948/d1020777
- Description: Marechera the Zimbabwean writer, poet and novelist emerged in the late 1970s as a new voice in African literature, but his writing career lasted less than a decade. It was his iconoclastic, dense style that expressed the psychological disintegration prevalent in Africa during this period and challenged the central beliefs of both the nationalist and post-independence eras. Defying the limitations of nationality, race and culture, Marechera’s writing explores universal issues, particularly urban existence in the late twentieth century. Marechera’s life and work were closely linked. His outspoken views and unorthodox lifestyle brought him into frequent conflict with the authorities and contributed to him being perceived as a cult figure. Through his work and personality he became a major inspiration and role model for the younger generation of writers in Zimbabwe and other African countries. The present study is a psychobiographical case study with the primary aim being to explore and describe the personality development of Dambudzo Marechera (1952-1987) using Alfred Adler’s theory of Individual Psychology. It was through the use of a theory of psychological development that a better understanding of Marechera’s personality, based on his cultural and historical background was achieved and a new interpretation and explanation was reported. The findings of the study can be generalised to the theory of individual psychology through the process of analytical generalization.
- Full Text:
- Date Issued: 2013
- Authors: Muchena, Kudakwashe Christopher
- Date: 2013
- Subjects: Marechera, Dambudzo, 1952-1987 , Developmental psychology , Psychology -- Biographical methods , Authors -- Biography , Authors, African -- 20th century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9964 , http://hdl.handle.net/10948/d1020777
- Description: Marechera the Zimbabwean writer, poet and novelist emerged in the late 1970s as a new voice in African literature, but his writing career lasted less than a decade. It was his iconoclastic, dense style that expressed the psychological disintegration prevalent in Africa during this period and challenged the central beliefs of both the nationalist and post-independence eras. Defying the limitations of nationality, race and culture, Marechera’s writing explores universal issues, particularly urban existence in the late twentieth century. Marechera’s life and work were closely linked. His outspoken views and unorthodox lifestyle brought him into frequent conflict with the authorities and contributed to him being perceived as a cult figure. Through his work and personality he became a major inspiration and role model for the younger generation of writers in Zimbabwe and other African countries. The present study is a psychobiographical case study with the primary aim being to explore and describe the personality development of Dambudzo Marechera (1952-1987) using Alfred Adler’s theory of Individual Psychology. It was through the use of a theory of psychological development that a better understanding of Marechera’s personality, based on his cultural and historical background was achieved and a new interpretation and explanation was reported. The findings of the study can be generalised to the theory of individual psychology through the process of analytical generalization.
- Full Text:
- Date Issued: 2013
Dancing with the devil: formative peer assessment and academic performance
- Mostert, Markus, Snowball, Jeanette D
- Authors: Mostert, Markus , Snowball, Jeanette D
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69301 , vital:29483 , https://doi.org/10.1080/07294360.2012.705262
- Description: Peer assessment can be important in developing active and independent learners, as well as providing more and faster feedback in large classes, compared to marking done by tutors. In addition, the evaluative, critical stance required by students in order to assess their peers' work encourages the development of higher-order cognitive skills. Changing roles from being assessed to being an assessor can also improve students' ability to judge and improve on their own work. However, peer assessment does have potential problems and there is some debate as to the appropriate academic level at which to implement it, the kinds of feedback that are given and the ways in which students respond. In addition, there is little evidence that peer assessment has an impact on academic performance. This research reports the results of an online peer assessment exercise for a macroeconomics essay conducted in a large Economics 1 class at Rhodes University. Of the 800 students, about half participated in the peer assessment exercise. Data were collected from students via a formal course evaluation. In addition, a sample of 50 essays was evaluated in terms of the relationship between peer marks and final (tutor) marks received and the impact that peer assessment had on the quality of the final essay submitted. An Ordinary Least Squares regression was used to investigate the impact of peer assessment participation on marks. Results showed that peer marks tended to ‘bunch’ in the 60–68% range, indicating the reluctance of peers to give very high or low marks. In general, peers gave more useful feedback on technical aspects, such as presentation and referencing (which were also the categories in which students most often made improvements), than on content. Regression analysis showed that peer assessment participation was not a significant determinant of final essay mark, but that economics ability and English language proficiency were.
- Full Text: false
- Date Issued: 2013
- Authors: Mostert, Markus , Snowball, Jeanette D
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69301 , vital:29483 , https://doi.org/10.1080/07294360.2012.705262
- Description: Peer assessment can be important in developing active and independent learners, as well as providing more and faster feedback in large classes, compared to marking done by tutors. In addition, the evaluative, critical stance required by students in order to assess their peers' work encourages the development of higher-order cognitive skills. Changing roles from being assessed to being an assessor can also improve students' ability to judge and improve on their own work. However, peer assessment does have potential problems and there is some debate as to the appropriate academic level at which to implement it, the kinds of feedback that are given and the ways in which students respond. In addition, there is little evidence that peer assessment has an impact on academic performance. This research reports the results of an online peer assessment exercise for a macroeconomics essay conducted in a large Economics 1 class at Rhodes University. Of the 800 students, about half participated in the peer assessment exercise. Data were collected from students via a formal course evaluation. In addition, a sample of 50 essays was evaluated in terms of the relationship between peer marks and final (tutor) marks received and the impact that peer assessment had on the quality of the final essay submitted. An Ordinary Least Squares regression was used to investigate the impact of peer assessment participation on marks. Results showed that peer marks tended to ‘bunch’ in the 60–68% range, indicating the reluctance of peers to give very high or low marks. In general, peers gave more useful feedback on technical aspects, such as presentation and referencing (which were also the categories in which students most often made improvements), than on content. Regression analysis showed that peer assessment participation was not a significant determinant of final essay mark, but that economics ability and English language proficiency were.
- Full Text: false
- Date Issued: 2013
Deagrarianisation and forest revegetation in a biodiversity hotspot on the Wild Coast, South Africa
- Shackleton, Ross T, Shackleton, Charlie M, Shackleton, Sheona E, Gambiza, James
- Authors: Shackleton, Ross T , Shackleton, Charlie M , Shackleton, Sheona E , Gambiza, James
- Date: 2013
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60984 , vital:27905 , doi:10.1371/journal.pone.0076939
- Description: Deagraianisation is a worldwide phenomenon with widespread social, ecological and economic effects yet with little consensus on the local or higher level causes. There have been contested views on the causes and consequences of deagrarianisation on South Africa’s Wild Coast, which is an international biodiversity hotspot. Using GIS, household interviews and ecological sampling, we compared the perspectives of current and former cultivators as to why some have abandoned farming, whilst also tracking the uses and woody plant cover and composition of fields abandoned at different periods. The GIS analysis showed that field abandonment had been ongoing over several decades, with a decline from 12.5 % field cover in 1961 to 2.7 % in 2009. The area of forests and woodlands almost doubled in the corresponding period. There was a distinct peak in field abandonment during the time of political transition at the national level in the early 1990s. This political change led to a decrease in government support for livestock farming, which in turn resulted in reduced animal draught power at the household and community level, and hence reduced cropping. The study showed it is largely the wealthier households that have remained in arable agriculture and that the poorer households have abandoned farming. The abandoned fields show a distinct trend of increasing woody biomass and species richness with length of time since abandonment, with approximately three woody plant species added per decade. Most local respondents dislike the increases in forest and woodland extent and density because of anxiety about wild animals causing harm to crops and even humans, and the loss of an agricultural identity to livelihoods and the landscape.
- Full Text:
- Date Issued: 2013
- Authors: Shackleton, Ross T , Shackleton, Charlie M , Shackleton, Sheona E , Gambiza, James
- Date: 2013
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60984 , vital:27905 , doi:10.1371/journal.pone.0076939
- Description: Deagraianisation is a worldwide phenomenon with widespread social, ecological and economic effects yet with little consensus on the local or higher level causes. There have been contested views on the causes and consequences of deagrarianisation on South Africa’s Wild Coast, which is an international biodiversity hotspot. Using GIS, household interviews and ecological sampling, we compared the perspectives of current and former cultivators as to why some have abandoned farming, whilst also tracking the uses and woody plant cover and composition of fields abandoned at different periods. The GIS analysis showed that field abandonment had been ongoing over several decades, with a decline from 12.5 % field cover in 1961 to 2.7 % in 2009. The area of forests and woodlands almost doubled in the corresponding period. There was a distinct peak in field abandonment during the time of political transition at the national level in the early 1990s. This political change led to a decrease in government support for livestock farming, which in turn resulted in reduced animal draught power at the household and community level, and hence reduced cropping. The study showed it is largely the wealthier households that have remained in arable agriculture and that the poorer households have abandoned farming. The abandoned fields show a distinct trend of increasing woody biomass and species richness with length of time since abandonment, with approximately three woody plant species added per decade. Most local respondents dislike the increases in forest and woodland extent and density because of anxiety about wild animals causing harm to crops and even humans, and the loss of an agricultural identity to livelihoods and the landscape.
- Full Text:
- Date Issued: 2013
Deconstructing Developmental Psychology–Twenty years on: Reflections, implications and empirical work
- Callaghan, A A Jane, Macleod, Catriona I
- Authors: Callaghan, A A Jane , Macleod, Catriona I
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/446231 , vital:74483 , xlink:href="https://doi.org/10.1177/0959353513495213"
- Description: Erica Burman’s book Deconstructing Developmental Psychology (DDP), which appeared in first edition in 1994 and in second edition in 2008, critically appraised mainstream psychology’s approaches to child development, using feminist and post-structuralist theory. In it she examines the historical contingencies and cultural assumptions that form the conditions of possibility for the elaboration of the various Developmental Psychology approaches. She shows how these approaches form powerful discursive resources in regulating women and families, in marginalizing working class and ethnic minority people, and in pathologizing mothers. In this special focus, to appear over three issues, we seek to unpack the impact of the book since its first publication 20 years ago.
- Full Text:
- Date Issued: 2013
- Authors: Callaghan, A A Jane , Macleod, Catriona I
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/446231 , vital:74483 , xlink:href="https://doi.org/10.1177/0959353513495213"
- Description: Erica Burman’s book Deconstructing Developmental Psychology (DDP), which appeared in first edition in 1994 and in second edition in 2008, critically appraised mainstream psychology’s approaches to child development, using feminist and post-structuralist theory. In it she examines the historical contingencies and cultural assumptions that form the conditions of possibility for the elaboration of the various Developmental Psychology approaches. She shows how these approaches form powerful discursive resources in regulating women and families, in marginalizing working class and ethnic minority people, and in pathologizing mothers. In this special focus, to appear over three issues, we seek to unpack the impact of the book since its first publication 20 years ago.
- Full Text:
- Date Issued: 2013
Deep Routing Simulation
- Irwin, Barry V W, Herbert, Alan
- Authors: Irwin, Barry V W , Herbert, Alan
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430353 , vital:72685 , https://www.academic-bookshop.com/ourshop/prod_2546879-ICIW-2013-8th-International-Conference-on-Information-Warfare-and-Security.html
- Description: This paper discusses a dataset of some 16 million packets targeting port 445/tcp collected by a network telescope utilising a /24 netblock in South African IP address space. An initial overview of the collected data is provided. This is followed by a detailed analysis of the packet characteristics observed, including size and TTL. The peculiarities of the observed target selection and the results of the flaw in the Conficker worm's propagation algorithm are presented. An analysis of the 4 million observed source hosts is reported, grouped by both packet counts and the number of distinct hosts per network address block. Address blocks of size /8, 16 and 24 are used for groupings. The localisation, by geographic region and numerical proximity, of high ranking aggregate netblocks is highlighted. The observed shift in geopolitical origins observed during the evolution of the Conficker worm is also discussed. The paper concludes with some overall analyses, and consideration of the application of network telescopes to the monitoring of such outbreaks in the future.
- Full Text:
- Date Issued: 2013
- Authors: Irwin, Barry V W , Herbert, Alan
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430353 , vital:72685 , https://www.academic-bookshop.com/ourshop/prod_2546879-ICIW-2013-8th-International-Conference-on-Information-Warfare-and-Security.html
- Description: This paper discusses a dataset of some 16 million packets targeting port 445/tcp collected by a network telescope utilising a /24 netblock in South African IP address space. An initial overview of the collected data is provided. This is followed by a detailed analysis of the packet characteristics observed, including size and TTL. The peculiarities of the observed target selection and the results of the flaw in the Conficker worm's propagation algorithm are presented. An analysis of the 4 million observed source hosts is reported, grouped by both packet counts and the number of distinct hosts per network address block. Address blocks of size /8, 16 and 24 are used for groupings. The localisation, by geographic region and numerical proximity, of high ranking aggregate netblocks is highlighted. The observed shift in geopolitical origins observed during the evolution of the Conficker worm is also discussed. The paper concludes with some overall analyses, and consideration of the application of network telescopes to the monitoring of such outbreaks in the future.
- Full Text:
- Date Issued: 2013
Defamation détente Gorbachev glasnost perestroika invasion of privacy: regulation, ethics, accountability
- Authors: Copteros, Stratos
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454656 , vital:75363 , https://hdl.handle.net/10520/EJC141582
- Description: It was the final year of my BA in International Relations. 1988. Studying a Cold War whose freeze was thawing fast. Indeed, everything was changing so rapidly since Gorbachev's arrival that our bibliographies included that week's Time, Newsweek, Economist and every other cur-rent publication of a then Google-free world.
- Full Text:
- Date Issued: 2013
- Authors: Copteros, Stratos
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/454656 , vital:75363 , https://hdl.handle.net/10520/EJC141582
- Description: It was the final year of my BA in International Relations. 1988. Studying a Cold War whose freeze was thawing fast. Indeed, everything was changing so rapidly since Gorbachev's arrival that our bibliographies included that week's Time, Newsweek, Economist and every other cur-rent publication of a then Google-free world.
- Full Text:
- Date Issued: 2013
Deploying DNSSEC in islands of security
- Authors: Murisa, Wesley Vengayi
- Date: 2013 , 2013-03-31
- Subjects: Internet domain names , Computer security , Computer network protocols , Computer security -- Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4577 , http://hdl.handle.net/10962/d1003053 , Internet domain names , Computer security , Computer network protocols , Computer security -- Africa
- Description: The Domain Name System (DNS), a name resolution protocol is one of the vulnerable network protocols that has been subjected to many security attacks such as cache poisoning, denial of service and the 'Kaminsky' spoofing attack. When DNS was designed, security was not incorporated into its design. The DNS Security Extensions (DNSSEC) provides security to the name resolution process by using public key cryptosystems. Although DNSSEC has backward compatibility with unsecured zones, it only offers security to clients when communicating with security aware zones. Widespread deployment of DNSSEC is therefore necessary to secure the name resolution process and provide security to the Internet. Only a few Top Level Domains (TLD's) have deployed DNSSEC, this inherently makes it difficult for their sub-domains to implement the security extensions to the DNS. This study analyses mechanisms that can be used by domains in islands of security to deploy DNSSEC so that the name resolution process can be secured in two specific cases where either the TLD is not signed or the domain registrar is not able to support signed domains. The DNS client side mechanisms evaluated in this study include web browser plug-ins, local validating resolvers and domain look-aside validation. The results of the study show that web browser plug-ins cannot work on their own without local validating resolvers. The web browser validators, however, proved to be useful in indicating to the user whether a domain has been validated or not. Local resolvers present a more secure option for Internet users who cannot trust the communication channel between their stub resolvers and remote name servers. However, they do not provide a way of showing the user whether a domain name has been correctly validated or not. Based on the results of the tests conducted, it is recommended that local validators be used with browser validators for visibility and improved security. On the DNS server side, Domain Look-aside Validation (DLV) presents a viable alternative for organizations in islands of security like most countries in Africa where only two country code Top Level Domains (ccTLD) have deployed DNSSEC. This research recommends use of DLV by corporates to provide DNS security to both internal and external users accessing their web based services. , LaTeX with hyperref package , pdfTeX-1.40.10
- Full Text:
- Date Issued: 2013
- Authors: Murisa, Wesley Vengayi
- Date: 2013 , 2013-03-31
- Subjects: Internet domain names , Computer security , Computer network protocols , Computer security -- Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4577 , http://hdl.handle.net/10962/d1003053 , Internet domain names , Computer security , Computer network protocols , Computer security -- Africa
- Description: The Domain Name System (DNS), a name resolution protocol is one of the vulnerable network protocols that has been subjected to many security attacks such as cache poisoning, denial of service and the 'Kaminsky' spoofing attack. When DNS was designed, security was not incorporated into its design. The DNS Security Extensions (DNSSEC) provides security to the name resolution process by using public key cryptosystems. Although DNSSEC has backward compatibility with unsecured zones, it only offers security to clients when communicating with security aware zones. Widespread deployment of DNSSEC is therefore necessary to secure the name resolution process and provide security to the Internet. Only a few Top Level Domains (TLD's) have deployed DNSSEC, this inherently makes it difficult for their sub-domains to implement the security extensions to the DNS. This study analyses mechanisms that can be used by domains in islands of security to deploy DNSSEC so that the name resolution process can be secured in two specific cases where either the TLD is not signed or the domain registrar is not able to support signed domains. The DNS client side mechanisms evaluated in this study include web browser plug-ins, local validating resolvers and domain look-aside validation. The results of the study show that web browser plug-ins cannot work on their own without local validating resolvers. The web browser validators, however, proved to be useful in indicating to the user whether a domain has been validated or not. Local resolvers present a more secure option for Internet users who cannot trust the communication channel between their stub resolvers and remote name servers. However, they do not provide a way of showing the user whether a domain name has been correctly validated or not. Based on the results of the tests conducted, it is recommended that local validators be used with browser validators for visibility and improved security. On the DNS server side, Domain Look-aside Validation (DLV) presents a viable alternative for organizations in islands of security like most countries in Africa where only two country code Top Level Domains (ccTLD) have deployed DNSSEC. This research recommends use of DLV by corporates to provide DNS security to both internal and external users accessing their web based services. , LaTeX with hyperref package , pdfTeX-1.40.10
- Full Text:
- Date Issued: 2013
Describing the relationship between the cognitive and linguistic complexity of a mathematical literacy examination and types of student errors
- Authors: Vale, Pamela
- Date: 2013
- Subjects: Mathematics -- Study and teaching (Secondary) -- Research -- South Africa Mathematics -- Study and teaching (Secondary) -- South Africa -- Evaluation Mathematics -- Study and teaching (Secondary) -- South Africa -- Evaluation Communication in foreign language education -- Research -- South Africa Communication in foreign language education -- Research -- South Africa Education, Secondary -- Research -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1397 , http://hdl.handle.net/10962/d1001774
- Description: Much prior research has shown that if students have a poor command of the language in which they are taught and assessed, they experience a complex and deep learning disadvantage (Barton & Neville-Barton, 2003). Abedi (2006) mentions, in particular, that unnecessary linguistic complexity can threaten the validity of examination items and thus compromises the fairness of the assessment for English language learners. In Clarkson’s (1991, p. 31) research it was found that for the English language learners in the study “comprehension errors [made] up a high proportion of the errors made when…students attempt[ed] to solve mathematical word problems”. In an attempt to explore whether this was the case for a group of National Certificate (Vocational) [NC(V)] students at an FET college, the research conducted in this study focused on describing the cognitive and linguistic complexity of Level 4 Mathematical Literacy examination items as well as the types of responses from a sample of students. A mixed-methods case study design was selected. Student errors were classified as either due to mathematical literacy-related sources, or language-related sources and the question was asked as to how the cognitive and linguistic complexity of items might be related to the types of errors made. Statistically significant correlations were found between the linguistic complexity of items and language-related errors, and between the cognitive complexity of items and all types of errors. It was also possible to identify which language features, in particular, were statistically significantly correlated with linguistic complexity, namely: prepositional phrases; words of 7 letters or more and complex/compound sentences. As was expected, the majority of errors were categorised as mathematical literacy-related. However, as many as 19.22% of all errors made were identified as language-related. While the scope of the study prevents any generalisations from being made, the results indicate a need for a larger-scale study of this nature to determine if the complex and deep learning disadvantage mentioned by Barton and Neville-Barton (2003) does exist with regard to the assessment of Mathematical Literacy for NC(V) students who are English language learners (Barton & Neville-Barton, 2003).
- Full Text:
- Date Issued: 2013
- Authors: Vale, Pamela
- Date: 2013
- Subjects: Mathematics -- Study and teaching (Secondary) -- Research -- South Africa Mathematics -- Study and teaching (Secondary) -- South Africa -- Evaluation Mathematics -- Study and teaching (Secondary) -- South Africa -- Evaluation Communication in foreign language education -- Research -- South Africa Communication in foreign language education -- Research -- South Africa Education, Secondary -- Research -- South Africa
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1397 , http://hdl.handle.net/10962/d1001774
- Description: Much prior research has shown that if students have a poor command of the language in which they are taught and assessed, they experience a complex and deep learning disadvantage (Barton & Neville-Barton, 2003). Abedi (2006) mentions, in particular, that unnecessary linguistic complexity can threaten the validity of examination items and thus compromises the fairness of the assessment for English language learners. In Clarkson’s (1991, p. 31) research it was found that for the English language learners in the study “comprehension errors [made] up a high proportion of the errors made when…students attempt[ed] to solve mathematical word problems”. In an attempt to explore whether this was the case for a group of National Certificate (Vocational) [NC(V)] students at an FET college, the research conducted in this study focused on describing the cognitive and linguistic complexity of Level 4 Mathematical Literacy examination items as well as the types of responses from a sample of students. A mixed-methods case study design was selected. Student errors were classified as either due to mathematical literacy-related sources, or language-related sources and the question was asked as to how the cognitive and linguistic complexity of items might be related to the types of errors made. Statistically significant correlations were found between the linguistic complexity of items and language-related errors, and between the cognitive complexity of items and all types of errors. It was also possible to identify which language features, in particular, were statistically significantly correlated with linguistic complexity, namely: prepositional phrases; words of 7 letters or more and complex/compound sentences. As was expected, the majority of errors were categorised as mathematical literacy-related. However, as many as 19.22% of all errors made were identified as language-related. While the scope of the study prevents any generalisations from being made, the results indicate a need for a larger-scale study of this nature to determine if the complex and deep learning disadvantage mentioned by Barton and Neville-Barton (2003) does exist with regard to the assessment of Mathematical Literacy for NC(V) students who are English language learners (Barton & Neville-Barton, 2003).
- Full Text:
- Date Issued: 2013
Design and evaluation of an electrochemical immunosensor for measles serodiagnosis using measles-specific Immunoglobulin G antibodies
- Mashazi, Philani N, Vilakazi, Sibulelo, Nyokong, Tebello
- Authors: Mashazi, Philani N , Vilakazi, Sibulelo , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241705 , vital:50962 , xlink:href="https://doi.org/10.1016/j.talanta.2013.06.036"
- Description: The design of electrochemical immunosensors for the detection of measles-specific antibodies is reported. The measles-antigen modified surface was used as an antibody capture surface. The detection of measles-specific IgG antibodies was accomplished using the voltammetric method and horse-radish peroxidase (HRP) labeled secondary antibody (anti-IgG) as a detecting antibody. The potential applications of the designed immunosensor were evaluated in buffer and serum solutions. The immunosensor exhibited good linearity at concentrations less than 100 ng mL−1 with R2=0.997 and the limit of detection of 6.60 ng mL−1 at 3σ. The potential application of the immunosensor was evaluated in the deliberately infected human and newborn calf serum samples with measles-IgG antibody mimicking real-life samples. The designed electrochemical immunosensor could differentiate between infected and un-infected serum samples as higher catalytic currents were obtained for infected serum samples.
- Full Text:
- Date Issued: 2013
- Authors: Mashazi, Philani N , Vilakazi, Sibulelo , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241705 , vital:50962 , xlink:href="https://doi.org/10.1016/j.talanta.2013.06.036"
- Description: The design of electrochemical immunosensors for the detection of measles-specific antibodies is reported. The measles-antigen modified surface was used as an antibody capture surface. The detection of measles-specific IgG antibodies was accomplished using the voltammetric method and horse-radish peroxidase (HRP) labeled secondary antibody (anti-IgG) as a detecting antibody. The potential applications of the designed immunosensor were evaluated in buffer and serum solutions. The immunosensor exhibited good linearity at concentrations less than 100 ng mL−1 with R2=0.997 and the limit of detection of 6.60 ng mL−1 at 3σ. The potential application of the immunosensor was evaluated in the deliberately infected human and newborn calf serum samples with measles-IgG antibody mimicking real-life samples. The designed electrochemical immunosensor could differentiate between infected and un-infected serum samples as higher catalytic currents were obtained for infected serum samples.
- Full Text:
- Date Issued: 2013
Design of Realistic Hybrid Marine Resource Management Programs in Oceania
- Aswani, Shankar, Ruddle, Kenneth
- Authors: Aswani, Shankar , Ruddle, Kenneth
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/422721 , vital:71972 , xlink:href="https://doi.org/10.2984/67.3.11"
- Description: This review article synthesizes the authors' several decades of multidisciplinary natural and social science and applied marine resource management experience in the Asia-Pacific region to examine the strengthening of coastal and marine resource management and conservation using alliances between local communities and external institutions. The objective is to assist the design of resource management and conservation programs that enhance the capacity of coastal communities in Oceania to confront both diminishing marine resources and the effects of climate change by providing guidelines for protecting marine biodiversity and vulnerable ecosystem functions. This article describes a management framework that hybridizes local beliefs and institutions expressed in customary management (CM) with such modern management concepts as marine protected areas (MPAs) and ecosystem-based management (EBM). Hybrid management accommodates the social, political, economic, and cultural contexts of Oceanic communities and, compared with recent or conventional management approaches, can therefore better address fundamental local concerns such as coastal degradation, climate change, sea level rise, weak governance, corruption, limited resources and staff to manage and monitor marine resources, and increasing poverty. Research on the hybridization of management systems demonstrates opportunities to establish context-appropriate EBM and/or other managerial arrangements that include terrestrial and adjacent coastal-marine ecosystems. Formal and informal CM systems are widespread in Oceania and in some parts of Southeast Asia, and if appropriate strategies are employed rapid progress toward hybrid CM-EBM could be enabled.
- Full Text:
- Date Issued: 2013
- Authors: Aswani, Shankar , Ruddle, Kenneth
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/422721 , vital:71972 , xlink:href="https://doi.org/10.2984/67.3.11"
- Description: This review article synthesizes the authors' several decades of multidisciplinary natural and social science and applied marine resource management experience in the Asia-Pacific region to examine the strengthening of coastal and marine resource management and conservation using alliances between local communities and external institutions. The objective is to assist the design of resource management and conservation programs that enhance the capacity of coastal communities in Oceania to confront both diminishing marine resources and the effects of climate change by providing guidelines for protecting marine biodiversity and vulnerable ecosystem functions. This article describes a management framework that hybridizes local beliefs and institutions expressed in customary management (CM) with such modern management concepts as marine protected areas (MPAs) and ecosystem-based management (EBM). Hybrid management accommodates the social, political, economic, and cultural contexts of Oceanic communities and, compared with recent or conventional management approaches, can therefore better address fundamental local concerns such as coastal degradation, climate change, sea level rise, weak governance, corruption, limited resources and staff to manage and monitor marine resources, and increasing poverty. Research on the hybridization of management systems demonstrates opportunities to establish context-appropriate EBM and/or other managerial arrangements that include terrestrial and adjacent coastal-marine ecosystems. Formal and informal CM systems are widespread in Oceania and in some parts of Southeast Asia, and if appropriate strategies are employed rapid progress toward hybrid CM-EBM could be enabled.
- Full Text:
- Date Issued: 2013
Design, implementation and evaluation of a directly water cooled photovoltaic- thermal system
- Authors: Mtunzi, Busiso
- Date: 2013
- Subjects: Sensitivity analysis -- Photovoltaic thermal system (PV/T) , Solar utilization -- Carbon emission
- Language: English
- Type: Thesis , Doctoral , PhD (Physics)
- Identifier: vital:11597 , http://hdl.handle.net/10353/d1016198 , Sensitivity analysis -- Photovoltaic thermal system (PV/T) , Solar utilization -- Carbon emission
- Description: This research project was based on the Design, Implementation and Evaluation of a Photovoltaic Water heating system in South Africa, Eastern Cape Province. The purpose of the study was to design and investigate the scientific and economic contribution of direct water cooling on the photovoltaic module. The method involved performance comparison of two photovoltaic modules, one naturally cooled (M1) and the other, direct water cooled module (M2). Module M2 was used to produce warm water and electricity, hence, a hybrid system. The study focused on comparing the modules’ efficiency, power output and their performance. The temperatures attained by water through cooling the module were monitored as well as the electrical energy generated. A data logger and a low cost I/V characteristic system were used for data collection for a full year. The data were then used for performance analysis of the modules. The results of the study revealed that the directly water cooled module could operate at a higher electrical efficiency for 87% of the day and initially produced 3.63% more electrical energy each day. This was found to be true for the first three months after installation. In the remaining months to the end of the year M2 was found to have more losses as compared to M1 as evidenced by the modules’ performance ratios. The directly water cooled module also showed an energy saving efficiency of 61%. A solar utilization of 47.93% was found for M2 while 8.77% was found for M1. Economically, the project was found to be viable and the payback period of the directly cooled module (M2) system was found to be 9.8 years. Energy economics showed that the system was more sensitive to the price changes and to the energy output as compared to other inputs such as operation and maintenance and years of operation. A generation cost of R0.84/kWh from the system was found and when compared to the potential revenue of R1.18 per kWh, the system was found to enable households to make a profit of 40.5 %. Use of such a system was also found to be able to contribute 9.55% towards carbon emission reduction each year. From these results, it was concluded that a directly cooled photovoltaic/thermal heating (PV/T) system is possible and that it can be of much help in terms of warm water and electricity provision.
- Full Text:
- Date Issued: 2013
- Authors: Mtunzi, Busiso
- Date: 2013
- Subjects: Sensitivity analysis -- Photovoltaic thermal system (PV/T) , Solar utilization -- Carbon emission
- Language: English
- Type: Thesis , Doctoral , PhD (Physics)
- Identifier: vital:11597 , http://hdl.handle.net/10353/d1016198 , Sensitivity analysis -- Photovoltaic thermal system (PV/T) , Solar utilization -- Carbon emission
- Description: This research project was based on the Design, Implementation and Evaluation of a Photovoltaic Water heating system in South Africa, Eastern Cape Province. The purpose of the study was to design and investigate the scientific and economic contribution of direct water cooling on the photovoltaic module. The method involved performance comparison of two photovoltaic modules, one naturally cooled (M1) and the other, direct water cooled module (M2). Module M2 was used to produce warm water and electricity, hence, a hybrid system. The study focused on comparing the modules’ efficiency, power output and their performance. The temperatures attained by water through cooling the module were monitored as well as the electrical energy generated. A data logger and a low cost I/V characteristic system were used for data collection for a full year. The data were then used for performance analysis of the modules. The results of the study revealed that the directly water cooled module could operate at a higher electrical efficiency for 87% of the day and initially produced 3.63% more electrical energy each day. This was found to be true for the first three months after installation. In the remaining months to the end of the year M2 was found to have more losses as compared to M1 as evidenced by the modules’ performance ratios. The directly water cooled module also showed an energy saving efficiency of 61%. A solar utilization of 47.93% was found for M2 while 8.77% was found for M1. Economically, the project was found to be viable and the payback period of the directly cooled module (M2) system was found to be 9.8 years. Energy economics showed that the system was more sensitive to the price changes and to the energy output as compared to other inputs such as operation and maintenance and years of operation. A generation cost of R0.84/kWh from the system was found and when compared to the potential revenue of R1.18 per kWh, the system was found to enable households to make a profit of 40.5 %. Use of such a system was also found to be able to contribute 9.55% towards carbon emission reduction each year. From these results, it was concluded that a directly cooled photovoltaic/thermal heating (PV/T) system is possible and that it can be of much help in terms of warm water and electricity provision.
- Full Text:
- Date Issued: 2013
Designing multi-touch tabletop interaction techniques to support co-located Group Information Management
- Authors: Ditta, Mohammed Ali
- Date: 2013
- Subjects: Groupware (Computer software) , Teams in the workplace -- Data processing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10493 , http://hdl.handle.net/10948/d1020639
- Description: Co-located group information management (GIM) is a form of groupware with the aim of enabling users to collaboratively find, store, maintain, organise and share personal and/or group information in support of a group activity. Existing systems aimed at partially supporting GIM activities have been implemented on single user devices. These systems make use of asynchronous communication that may hinder collaboration by misinterpretation, information leaks, etc. Few systems exist, with limited functionality, that support co-located GIM. Multi-touch tabletop interaction has given rise to a new approach for supporting Computer Supported Cooperative Work (CSCW). Multi-touch tabletops allow multiple users to naturally interact with a computer device using a shared display and gesture interaction. The tabletop environment also enables users to sit in a natural environment and synchronously communicate without bulky desktops or laptops. Multi-touch tabletops provide the hardware necessary to support co-located GIM. Existing multi-touch interaction techniques were analysed and proved insufficient to support the advanced functional requirements of GIM. The goal of this research was therefore to support co-located GIM by designing new multi-touch tabletop interaction techniques. An architecture was proposed to support co-located GIM with new multi-touch interaction techniques. A software prototype was developed based on the proposed architecture to facilitate the main activities of GIM and to collaboratively compile documents. The prototype was named CollaGIM (Colla – collaborative, GIM – group information management). CollaGIM supports the main activities of GIM using natural gesture interaction on a multi-touch tabletop. An evaluation of the software was conducted by means of a user study where 15 teams of two people participated. High task success rates and user satisfaction results were achieved, which showed that CollaGIM was capable of supporting co-located GIM using the new multi-touch tabletop interaction techniques. CollaGIM also positively supported collaboration between users.
- Full Text:
- Date Issued: 2013
- Authors: Ditta, Mohammed Ali
- Date: 2013
- Subjects: Groupware (Computer software) , Teams in the workplace -- Data processing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10493 , http://hdl.handle.net/10948/d1020639
- Description: Co-located group information management (GIM) is a form of groupware with the aim of enabling users to collaboratively find, store, maintain, organise and share personal and/or group information in support of a group activity. Existing systems aimed at partially supporting GIM activities have been implemented on single user devices. These systems make use of asynchronous communication that may hinder collaboration by misinterpretation, information leaks, etc. Few systems exist, with limited functionality, that support co-located GIM. Multi-touch tabletop interaction has given rise to a new approach for supporting Computer Supported Cooperative Work (CSCW). Multi-touch tabletops allow multiple users to naturally interact with a computer device using a shared display and gesture interaction. The tabletop environment also enables users to sit in a natural environment and synchronously communicate without bulky desktops or laptops. Multi-touch tabletops provide the hardware necessary to support co-located GIM. Existing multi-touch interaction techniques were analysed and proved insufficient to support the advanced functional requirements of GIM. The goal of this research was therefore to support co-located GIM by designing new multi-touch tabletop interaction techniques. An architecture was proposed to support co-located GIM with new multi-touch interaction techniques. A software prototype was developed based on the proposed architecture to facilitate the main activities of GIM and to collaboratively compile documents. The prototype was named CollaGIM (Colla – collaborative, GIM – group information management). CollaGIM supports the main activities of GIM using natural gesture interaction on a multi-touch tabletop. An evaluation of the software was conducted by means of a user study where 15 teams of two people participated. High task success rates and user satisfaction results were achieved, which showed that CollaGIM was capable of supporting co-located GIM using the new multi-touch tabletop interaction techniques. CollaGIM also positively supported collaboration between users.
- Full Text:
- Date Issued: 2013