Mentoring as a strategy to develop leadership potential of female employees
- Authors: Potgieter, Deidre
- Date: 2009
- Subjects: Mentoring in business , Leadership in women , Women employees
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9278 , http://hdl.handle.net/10948/1472 , Mentoring in business , Leadership in women , Women employees
- Description: Institutions of higher learning should be doing leadership development of females to enhance the gender balance. The number of females employed in South African higher education is almost equal to the number of males, yet the highest proportions of females continue to hold the lowest academic and support positions. To compound the problem, after attracting suitable female staff, institutions do not have programmes to encourage them to remain within the system. Females need to surmount extra hurdles to be considered as leaders, and have different experiences of organisations from those of their male peers. Research suggests that women have the qualifications, skills and experiences required for leadership. This study aimed to look at mentoring as a strategy to enhance female leadership development. A literature review was conducted to understand the term mentoring and all related aspects. The aspects included the functions and phases of mentoring, as well as the process of a mentoring programme. Recently organisations have begun to realise how important mentoring can be to their success. Research has shown that mentoring facilitates leadership development through the career and psycho-social functions that the relationship provides. The study also investigated gender and leadership, and highlighted the barriers faced by women. The empirical part of this study was to determine employees‘ perceptions of mentoring. It was conducted in a Higher Education Institution. Random sampling was used to select respondents. The sample size consisted of 110 respondents. A structured pre-coded questionnaire was used to collect the data. The data was analysed Abstract Page iii using the relevant statistical package. Independent t-tests and analysis of variance techniques were used to determine statistically significant differences in perceptions between groups according to race, qualifications, period of employment and the type of appointment (academic/administrative). Statistically significant differences were found between race groups and the period of employment. Qualification and type of appointment did not significantly affect employees‘ responses. The major findings indicate a general congruence towards mentoring as a suitable strategy to enhance female leadership development. Institutional barriers were identified and the organisation needs to acknowledge and understand the organisational culture before embarking on this process. The theoretical and practical implications of the findings are discussed and recommendations based on these findings are provided.
- Full Text:
- Date Issued: 2009
- Authors: Potgieter, Deidre
- Date: 2009
- Subjects: Mentoring in business , Leadership in women , Women employees
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9278 , http://hdl.handle.net/10948/1472 , Mentoring in business , Leadership in women , Women employees
- Description: Institutions of higher learning should be doing leadership development of females to enhance the gender balance. The number of females employed in South African higher education is almost equal to the number of males, yet the highest proportions of females continue to hold the lowest academic and support positions. To compound the problem, after attracting suitable female staff, institutions do not have programmes to encourage them to remain within the system. Females need to surmount extra hurdles to be considered as leaders, and have different experiences of organisations from those of their male peers. Research suggests that women have the qualifications, skills and experiences required for leadership. This study aimed to look at mentoring as a strategy to enhance female leadership development. A literature review was conducted to understand the term mentoring and all related aspects. The aspects included the functions and phases of mentoring, as well as the process of a mentoring programme. Recently organisations have begun to realise how important mentoring can be to their success. Research has shown that mentoring facilitates leadership development through the career and psycho-social functions that the relationship provides. The study also investigated gender and leadership, and highlighted the barriers faced by women. The empirical part of this study was to determine employees‘ perceptions of mentoring. It was conducted in a Higher Education Institution. Random sampling was used to select respondents. The sample size consisted of 110 respondents. A structured pre-coded questionnaire was used to collect the data. The data was analysed Abstract Page iii using the relevant statistical package. Independent t-tests and analysis of variance techniques were used to determine statistically significant differences in perceptions between groups according to race, qualifications, period of employment and the type of appointment (academic/administrative). Statistically significant differences were found between race groups and the period of employment. Qualification and type of appointment did not significantly affect employees‘ responses. The major findings indicate a general congruence towards mentoring as a suitable strategy to enhance female leadership development. Institutional barriers were identified and the organisation needs to acknowledge and understand the organisational culture before embarking on this process. The theoretical and practical implications of the findings are discussed and recommendations based on these findings are provided.
- Full Text:
- Date Issued: 2009
Key factors required to be classified as a world-class supplier from a South African automotive industry perspective
- Authors: Cook, Gavin Trevor
- Date: 2009
- Subjects: Automobile industry and trade -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9335 , http://hdl.handle.net/10948/935 , Automobile industry and trade -- South Africa
- Description: Over and above the fact that South African automotive business firms do not have the advantages of a major domestic market and are far removed from the major world markets, they face the challenges of operating in a tough and ever-changing environment. This environment is characterised by a global recession, aggressive global competition, high inflation and more demanding customers. To overcome these obstacles and to ensure their continuous success and existence, these domestic firms need to create a competitive advantage. The establishment of such a competitive advantage is dependent on a number of factors which mainly include sourcing from a world-class supplier base in terms of price, quality and service delivery. The main objective and central theme of this study is to determine the factors that are required by a supplier in the South African automotive industry to be classified as a world-class supplier. In support of the main objective, it was necessary to source the reasons why a firm would find it important to trade with a world-class supplier base, and to determine whether the current levels of supplier performance as experienced by buying firms in the Eastern Cape automotive industry, could be regarded as world-class. Furthermore, the study set out to determine the consequences to customer firms of inferior supplier performance, as well as the actions currently taken and support programmes in place to bring suppliers in line with world-class standards. As a starting point to the study, a literature review was undertaken which revealed the definite interdependence between a business firm and the environment in which it operates. The review underlined the need for environmental scanning as a means to proactively manage the impact of environmental changes on a firm. Porter’s value chain and business process re-engineering, as discussed in the study, are also perceived as means to manage environmental changes. The literature study further revealed some of the latest business trends followed by automotive business firms, as well as the expected supplier buy-in to ensure success. A statistical analysis on the quantitative data gathered, grouped specific items (questions) that relate to the study’s main objective with three respective individual supplier performance areas. A confirmatory factor analysis which focused on the three factors, namely quality, pricing and service delivery was carried out to assess the validity of the questions used for gathering the research data. The Cronbach Alphas determined for the three factors portrayed the reliability of the research instrument as acceptable. The empirical study revealed a few main factors that automotive business firms strongly perceive as being key to the establishment of a world-class supplier base. These factors are: a culture of continuous improvement; consistently meeting delivery deadlines by being able to respond to customer schedule changes; quoting fair prices and having respect for business ethics; as well as the consistent application of a quality policy which leads to conformance to specifications and subsequent high levels of product reliability. The empirical study also identified the following benefits enjoyed by customer business firms when trading with a world-class supplier base: Firms are able to be more flexible to customer schedule changes; they receive products that meet specifications; and they are able to operate at lower costs. The empirical findings with regard to the current level of supplier performance in the Eastern Cape Province automotive industry highlighted mainly three problem areas. These are late deliveries; the inability of suppliers to respond to customer schedule changes; as well as a lack of continuous improvement. Late deliveries which lead to production stoppages, with its resultant high costs, as well as the receipt of below-par quality products, were revealed as the main consequences when dealing with suppliers whose performance are not world-class. The main actions taken and programmes or incentives offered by automotive business firms to bring inferior suppliers more in line with world-class performance, include the rewarding of good suppliers by granting them more business; applying formal supplier performance evaluations; and having regular supplier audits.
- Full Text:
- Date Issued: 2009
- Authors: Cook, Gavin Trevor
- Date: 2009
- Subjects: Automobile industry and trade -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9335 , http://hdl.handle.net/10948/935 , Automobile industry and trade -- South Africa
- Description: Over and above the fact that South African automotive business firms do not have the advantages of a major domestic market and are far removed from the major world markets, they face the challenges of operating in a tough and ever-changing environment. This environment is characterised by a global recession, aggressive global competition, high inflation and more demanding customers. To overcome these obstacles and to ensure their continuous success and existence, these domestic firms need to create a competitive advantage. The establishment of such a competitive advantage is dependent on a number of factors which mainly include sourcing from a world-class supplier base in terms of price, quality and service delivery. The main objective and central theme of this study is to determine the factors that are required by a supplier in the South African automotive industry to be classified as a world-class supplier. In support of the main objective, it was necessary to source the reasons why a firm would find it important to trade with a world-class supplier base, and to determine whether the current levels of supplier performance as experienced by buying firms in the Eastern Cape automotive industry, could be regarded as world-class. Furthermore, the study set out to determine the consequences to customer firms of inferior supplier performance, as well as the actions currently taken and support programmes in place to bring suppliers in line with world-class standards. As a starting point to the study, a literature review was undertaken which revealed the definite interdependence between a business firm and the environment in which it operates. The review underlined the need for environmental scanning as a means to proactively manage the impact of environmental changes on a firm. Porter’s value chain and business process re-engineering, as discussed in the study, are also perceived as means to manage environmental changes. The literature study further revealed some of the latest business trends followed by automotive business firms, as well as the expected supplier buy-in to ensure success. A statistical analysis on the quantitative data gathered, grouped specific items (questions) that relate to the study’s main objective with three respective individual supplier performance areas. A confirmatory factor analysis which focused on the three factors, namely quality, pricing and service delivery was carried out to assess the validity of the questions used for gathering the research data. The Cronbach Alphas determined for the three factors portrayed the reliability of the research instrument as acceptable. The empirical study revealed a few main factors that automotive business firms strongly perceive as being key to the establishment of a world-class supplier base. These factors are: a culture of continuous improvement; consistently meeting delivery deadlines by being able to respond to customer schedule changes; quoting fair prices and having respect for business ethics; as well as the consistent application of a quality policy which leads to conformance to specifications and subsequent high levels of product reliability. The empirical study also identified the following benefits enjoyed by customer business firms when trading with a world-class supplier base: Firms are able to be more flexible to customer schedule changes; they receive products that meet specifications; and they are able to operate at lower costs. The empirical findings with regard to the current level of supplier performance in the Eastern Cape Province automotive industry highlighted mainly three problem areas. These are late deliveries; the inability of suppliers to respond to customer schedule changes; as well as a lack of continuous improvement. Late deliveries which lead to production stoppages, with its resultant high costs, as well as the receipt of below-par quality products, were revealed as the main consequences when dealing with suppliers whose performance are not world-class. The main actions taken and programmes or incentives offered by automotive business firms to bring inferior suppliers more in line with world-class performance, include the rewarding of good suppliers by granting them more business; applying formal supplier performance evaluations; and having regular supplier audits.
- Full Text:
- Date Issued: 2009
An investigation into the antimicrobial and anticancer activities of Geranium incanum, Artemisia afra and Artemisia absinthium
- Authors: Freidberg, Ryno
- Date: 2009
- Subjects: Medicinal plants -- South Africa , Cancer -- Alternative treatment -- South Africa , Anti-infective agents
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10122 , http://hdl.handle.net/10948/1045 , Medicinal plants -- South Africa , Cancer -- Alternative treatment -- South Africa , Anti-infective agents
- Description: It has been estimated that between 3000 and 4000 plant species are used for their medicinal properties throughout South Africa, with approximately 27 million South Africans making use of traditional medicines. Of this 27 million, 3 million South Africans rely on traditional medicine as their primary source of health care. Of the 250 000 to 500 000 known plant species, very few have been investigated for their pharmacological qualities, and compounds of significant medicinal value may still remain undiscovered in many plant species. The aims of this study included investigating the antimicrobial properties of Geranium incanum and Artemisia afra, both plants traditionally used for their medicinal properties, and comparing the antimicrobial activity of the latter to that of Artemisia absinthium, as well as investigating the anticancer properties of G. incanum and A. afra, and comparing the anticancer activity of the latter to that of A. absinthium. Infusions, aqueous-, methanol- and acetone extracts of the three plants were prepared and used for anticancer and antimicrobial screening. Plant specimens used to prepare extracts for antimicrobial activity were collected and extracted over three seasons, while extracts used for anticancer screening were prepared from plants collected during the summer only. Considerable variation existed in the percentage crude extract yields obtained when different extractants were used, while the season in which the plants were harvested and extracted also appeared to play a significant role in the amount of extract obtained. The plant extracts were screened for antimicrobial activity against various strains of Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus and Bacillus cereus, using an agar dilution method. G. incanum and A. afra possessed activity for C. albicans, while all three plants showed activity for S. aureus and B. cereus. Activity was largely dependent on the extraction method used. iii The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay was used to screen for anticancer activity of the respective extracts, at varying concentrations, against MCF-7 (human breast adenocarcinoma) cells, HT-29 (human colonic adenocarcinoma) cells and HeLa (human cervical cancer) cells. All of the extracts showed cytotoxic activity in all three cell lines to varying extents, depending on the extract used and cell line screened. The acetone extract of A. afra proved to be the most effective inhibitor with the lowest IC50 (2.65 ± 1.05 μg/ml) having been shown in MCF-7 cells. A. afra and A. absinthium showed similar inhibitory patterns, with the methanol- and acetone extracts having been the most potent inhibitors of each of the respective cell lines in general. Fluorescence microscopy employing 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) and propidium iodide (PI) staining indicated that the acetone extract of A. afra induces apoptosis in MCF-7 cells as apposed to necrosis, and the results were comparable to those obtained for cells exposed to cisplatin. Screening of the A. afra acetone extract for toxicity in normal human cells using the CellTiter-Blue® assay indicated the extract to be toxic to peripheral blood mononuclear cells (PBMC’s) at concentrations comparable to that for MCF-7 cells, while cell cycle analysis of MCF-7 cells exposed to the A. afra acetone extract indicated the extract’s ability to induce apoptosis comparable to that of cisplatin, with the extract exerting its activity at a point during or just prior to the S phase of the cell cycle.
- Full Text:
- Date Issued: 2009
- Authors: Freidberg, Ryno
- Date: 2009
- Subjects: Medicinal plants -- South Africa , Cancer -- Alternative treatment -- South Africa , Anti-infective agents
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10122 , http://hdl.handle.net/10948/1045 , Medicinal plants -- South Africa , Cancer -- Alternative treatment -- South Africa , Anti-infective agents
- Description: It has been estimated that between 3000 and 4000 plant species are used for their medicinal properties throughout South Africa, with approximately 27 million South Africans making use of traditional medicines. Of this 27 million, 3 million South Africans rely on traditional medicine as their primary source of health care. Of the 250 000 to 500 000 known plant species, very few have been investigated for their pharmacological qualities, and compounds of significant medicinal value may still remain undiscovered in many plant species. The aims of this study included investigating the antimicrobial properties of Geranium incanum and Artemisia afra, both plants traditionally used for their medicinal properties, and comparing the antimicrobial activity of the latter to that of Artemisia absinthium, as well as investigating the anticancer properties of G. incanum and A. afra, and comparing the anticancer activity of the latter to that of A. absinthium. Infusions, aqueous-, methanol- and acetone extracts of the three plants were prepared and used for anticancer and antimicrobial screening. Plant specimens used to prepare extracts for antimicrobial activity were collected and extracted over three seasons, while extracts used for anticancer screening were prepared from plants collected during the summer only. Considerable variation existed in the percentage crude extract yields obtained when different extractants were used, while the season in which the plants were harvested and extracted also appeared to play a significant role in the amount of extract obtained. The plant extracts were screened for antimicrobial activity against various strains of Candida albicans, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus and Bacillus cereus, using an agar dilution method. G. incanum and A. afra possessed activity for C. albicans, while all three plants showed activity for S. aureus and B. cereus. Activity was largely dependent on the extraction method used. iii The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay was used to screen for anticancer activity of the respective extracts, at varying concentrations, against MCF-7 (human breast adenocarcinoma) cells, HT-29 (human colonic adenocarcinoma) cells and HeLa (human cervical cancer) cells. All of the extracts showed cytotoxic activity in all three cell lines to varying extents, depending on the extract used and cell line screened. The acetone extract of A. afra proved to be the most effective inhibitor with the lowest IC50 (2.65 ± 1.05 μg/ml) having been shown in MCF-7 cells. A. afra and A. absinthium showed similar inhibitory patterns, with the methanol- and acetone extracts having been the most potent inhibitors of each of the respective cell lines in general. Fluorescence microscopy employing 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) and propidium iodide (PI) staining indicated that the acetone extract of A. afra induces apoptosis in MCF-7 cells as apposed to necrosis, and the results were comparable to those obtained for cells exposed to cisplatin. Screening of the A. afra acetone extract for toxicity in normal human cells using the CellTiter-Blue® assay indicated the extract to be toxic to peripheral blood mononuclear cells (PBMC’s) at concentrations comparable to that for MCF-7 cells, while cell cycle analysis of MCF-7 cells exposed to the A. afra acetone extract indicated the extract’s ability to induce apoptosis comparable to that of cisplatin, with the extract exerting its activity at a point during or just prior to the S phase of the cell cycle.
- Full Text:
- Date Issued: 2009
Factors influencing international students' choice of enrolling at higher education institutions via the internet
- Authors: Yang, Ning
- Date: 2009
- Subjects: Internet marketing -- South Africa , Education, Higher -- Marketing , Internet in higher education -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9338 , http://hdl.handle.net/10948/1084 , Internet marketing -- South Africa , Education, Higher -- Marketing , Internet in higher education -- South Africa
- Description: As the competition increase in the Higher Education industry, marketing departments of Higher Education Institutions view students as consumers and market their institutions. At the mean time, universities around the world encourage their international offices to increase the foreign student enrollments. This research investigates the factors influencing international students’ choice of enrolling at Higher Educational Institutions (HEI) via the internet: international students’ Internet use to facilitate information search and decision making. This survey of international students from Nelson Mandela Metropolitan University (NMMU) explored the Internet’s role in marketing international education. Based on this exploratory research, NMMU educational institutions gain insights of online customer service for successfully recruiting students. The results show that prospective overseas students do indeed use the internet. Overall evaluation of the factors influencing the use of the internet for enrolling at HEIs was determined by four factors: namely, perceived usefulness, consumer involvement, perceived ease of use and opinion leadership.
- Full Text:
- Date Issued: 2009
- Authors: Yang, Ning
- Date: 2009
- Subjects: Internet marketing -- South Africa , Education, Higher -- Marketing , Internet in higher education -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9338 , http://hdl.handle.net/10948/1084 , Internet marketing -- South Africa , Education, Higher -- Marketing , Internet in higher education -- South Africa
- Description: As the competition increase in the Higher Education industry, marketing departments of Higher Education Institutions view students as consumers and market their institutions. At the mean time, universities around the world encourage their international offices to increase the foreign student enrollments. This research investigates the factors influencing international students’ choice of enrolling at Higher Educational Institutions (HEI) via the internet: international students’ Internet use to facilitate information search and decision making. This survey of international students from Nelson Mandela Metropolitan University (NMMU) explored the Internet’s role in marketing international education. Based on this exploratory research, NMMU educational institutions gain insights of online customer service for successfully recruiting students. The results show that prospective overseas students do indeed use the internet. Overall evaluation of the factors influencing the use of the internet for enrolling at HEIs was determined by four factors: namely, perceived usefulness, consumer involvement, perceived ease of use and opinion leadership.
- Full Text:
- Date Issued: 2009
An investigation into user interface factors impacting on user experience: Pastel accounting case study
- Authors: Mashapa, Job
- Date: 2009
- Subjects: User interfaces (Computer systems) -- South Africa , Accounting -- Data processing , Accounting -- Computer programs , Small business -- South Africa -- Computer network resources
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9762 , http://hdl.handle.net/10948/1184 , User interfaces (Computer systems) -- South Africa , Accounting -- Data processing , Accounting -- Computer programs , Small business -- South Africa -- Computer network resources
- Description: The purpose of this research is to propose metrics to evaluate the user interface factors that impact on the user experience of Software Accounting Applications (SAAs) used to support the accounting business activities in Small Medium and Micro Enterprises (SMMEs) operating in developing countries. The research commences by outlining the conceptual background that introduces the study. In the introductory chapter, the problems together with the objectives that motivate the significance of the study are presented. In the same chapter, the overall research focus and how each of the research questions are treated to accomplish the intended goals are defined. In Chapter 2, the typical accounting business activities for SMMEs operating in developing countries are investigated. Findings from the preliminary survey revealed that Pastel accounting is the commonly used SMME accounting application used in developing countries. Inventory management, cash book processing, preparation of financial statements, customer and supplier documents processing are revealed as the most prevalent SMME accounting activities. This chapter highlights the problems that inhibit the implementation and the delivery of full benefits of using these SAAs. After indentifying the SAA problems, user experience aspects of the SAA are addressed in Chapter 3. User experience (UX) is defined and existing UX evaluation criteria are discussed. The findings form the basis for choosing the applicable criteria for evaluating the User Interface (UI) factors impacting on the UX of Pastel accounting. The proposed user experience evaluation metrics are described in Chapter 4. A discussion on how the metrics are implemented and what UI aspect they measure is presented. The research design and methodology followed is discussed in Chapter 5. The chapter outlines the possible research philosophy, strategy, methods and data collecting methods. A choice is made about the appropriate approach to answer the stated research questions to satisfy the intended overall research objective. A phenomenologist, qualitative inductive approach is adopted in the study. A contextual inquiry case-study strategy is chosen as applicable to this research. Data is collected using expert reviews, user observation and subjective questionnaires. After the choice of the research techniques, the case study results are presented and analysed in Chapter 6. It is found that Pastel UI is attractive and the users are happy with the visual design of the application. The major factors that impact on Pastel accounting are its lack of 4 feedback and its complexity which makes it difficult for first time users to use the application and the paucity of the help function. After the observed findings, the conclusions and recommendations of the research are presented in Chapter 7. It has been concluded that Pastel accounting UI fails to captivate a positive user experience for first-time users; the users do not find the expected help from the Help function and are often left wondering about the status of the system and the outcome of their actions on a task. Recommendations on how designers would make Pastel user interface more helpful, easy to use, and provide adequate feedback are presented in Chapter 7.
- Full Text:
- Date Issued: 2009
- Authors: Mashapa, Job
- Date: 2009
- Subjects: User interfaces (Computer systems) -- South Africa , Accounting -- Data processing , Accounting -- Computer programs , Small business -- South Africa -- Computer network resources
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9762 , http://hdl.handle.net/10948/1184 , User interfaces (Computer systems) -- South Africa , Accounting -- Data processing , Accounting -- Computer programs , Small business -- South Africa -- Computer network resources
- Description: The purpose of this research is to propose metrics to evaluate the user interface factors that impact on the user experience of Software Accounting Applications (SAAs) used to support the accounting business activities in Small Medium and Micro Enterprises (SMMEs) operating in developing countries. The research commences by outlining the conceptual background that introduces the study. In the introductory chapter, the problems together with the objectives that motivate the significance of the study are presented. In the same chapter, the overall research focus and how each of the research questions are treated to accomplish the intended goals are defined. In Chapter 2, the typical accounting business activities for SMMEs operating in developing countries are investigated. Findings from the preliminary survey revealed that Pastel accounting is the commonly used SMME accounting application used in developing countries. Inventory management, cash book processing, preparation of financial statements, customer and supplier documents processing are revealed as the most prevalent SMME accounting activities. This chapter highlights the problems that inhibit the implementation and the delivery of full benefits of using these SAAs. After indentifying the SAA problems, user experience aspects of the SAA are addressed in Chapter 3. User experience (UX) is defined and existing UX evaluation criteria are discussed. The findings form the basis for choosing the applicable criteria for evaluating the User Interface (UI) factors impacting on the UX of Pastel accounting. The proposed user experience evaluation metrics are described in Chapter 4. A discussion on how the metrics are implemented and what UI aspect they measure is presented. The research design and methodology followed is discussed in Chapter 5. The chapter outlines the possible research philosophy, strategy, methods and data collecting methods. A choice is made about the appropriate approach to answer the stated research questions to satisfy the intended overall research objective. A phenomenologist, qualitative inductive approach is adopted in the study. A contextual inquiry case-study strategy is chosen as applicable to this research. Data is collected using expert reviews, user observation and subjective questionnaires. After the choice of the research techniques, the case study results are presented and analysed in Chapter 6. It is found that Pastel UI is attractive and the users are happy with the visual design of the application. The major factors that impact on Pastel accounting are its lack of 4 feedback and its complexity which makes it difficult for first time users to use the application and the paucity of the help function. After the observed findings, the conclusions and recommendations of the research are presented in Chapter 7. It has been concluded that Pastel accounting UI fails to captivate a positive user experience for first-time users; the users do not find the expected help from the Help function and are often left wondering about the status of the system and the outcome of their actions on a task. Recommendations on how designers would make Pastel user interface more helpful, easy to use, and provide adequate feedback are presented in Chapter 7.
- Full Text:
- Date Issued: 2009
Modelling and intelligent control of vehicle climatronic systems
- Sun, Jie
- Authors: Sun, Jie
- Date: 2009
- Subjects: Automobiles -- Air conditioning , Automobiles -- Motors -- Cooling systems , Automobiles -- Heating and ventilation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9600 , http://hdl.handle.net/10948/1118 , Automobiles -- Air conditioning , Automobiles -- Motors -- Cooling systems , Automobiles -- Heating and ventilation
- Description: The modelling and control method of a vehicle climatronic system, based on MATLAB/SIMULINK, is presented. In order to achieve high modelling accuracy, a developed simulation model library is introduced. The modelling approach is described and the developed models are validated with some of experimental data obtained. The models are nonlinear, independent of fluid type and based on thermo-dynamic principles. Analysis of the cooling circuit modelling and empirical real-time control models are created by using Fuzzy logic controller and Stateflow. Both of control input and output are implemented essentially at original vehicle CAN-Bus system. Feasible digital automatic control strategy basic to fuzzy theory, hardware and software solution are given. The simulation experiment is achieved with the Hardware-in-Loop technology. This control methodology is easily operated and worth applying for any further studies or methods.
- Full Text:
- Date Issued: 2009
- Authors: Sun, Jie
- Date: 2009
- Subjects: Automobiles -- Air conditioning , Automobiles -- Motors -- Cooling systems , Automobiles -- Heating and ventilation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9600 , http://hdl.handle.net/10948/1118 , Automobiles -- Air conditioning , Automobiles -- Motors -- Cooling systems , Automobiles -- Heating and ventilation
- Description: The modelling and control method of a vehicle climatronic system, based on MATLAB/SIMULINK, is presented. In order to achieve high modelling accuracy, a developed simulation model library is introduced. The modelling approach is described and the developed models are validated with some of experimental data obtained. The models are nonlinear, independent of fluid type and based on thermo-dynamic principles. Analysis of the cooling circuit modelling and empirical real-time control models are created by using Fuzzy logic controller and Stateflow. Both of control input and output are implemented essentially at original vehicle CAN-Bus system. Feasible digital automatic control strategy basic to fuzzy theory, hardware and software solution are given. The simulation experiment is achieved with the Hardware-in-Loop technology. This control methodology is easily operated and worth applying for any further studies or methods.
- Full Text:
- Date Issued: 2009
A framework for IT governance in small businesses
- Authors: Koornhof, Herman
- Date: 2009
- Subjects: Corporate governance -- South Africa , Organizational effectiveness -- South Africa , Organisational Management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9768 , http://hdl.handle.net/10948/994 , Corporate governance -- South Africa , Organizational effectiveness -- South Africa , Organisational Management
- Description: The primary objective of this treatise is to develop a framework that small businesses can use to implement IT governance. This framework for IT 6 Governance in Small Businesses, called ITGovSB, will be based primarily on the CobiT framework and the ISO/IEC 27002 information security controls. In order to achieve the primary objective, it is necessary to understand the differences between IT governance in small businesses and larger organisations. Consequently, one of the secondary objectives of the paper is to derive characteristics that define IT governance in small businesses. Another secondary objective is to implement the ITGovSB framework at a small business to evaluate its effectiveness.
- Full Text:
- Date Issued: 2009
- Authors: Koornhof, Herman
- Date: 2009
- Subjects: Corporate governance -- South Africa , Organizational effectiveness -- South Africa , Organisational Management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9768 , http://hdl.handle.net/10948/994 , Corporate governance -- South Africa , Organizational effectiveness -- South Africa , Organisational Management
- Description: The primary objective of this treatise is to develop a framework that small businesses can use to implement IT governance. This framework for IT 6 Governance in Small Businesses, called ITGovSB, will be based primarily on the CobiT framework and the ISO/IEC 27002 information security controls. In order to achieve the primary objective, it is necessary to understand the differences between IT governance in small businesses and larger organisations. Consequently, one of the secondary objectives of the paper is to derive characteristics that define IT governance in small businesses. Another secondary objective is to implement the ITGovSB framework at a small business to evaluate its effectiveness.
- Full Text:
- Date Issued: 2009
A model for enhancing presence handling in instant messaging
- Authors: Victor, Rudi
- Date: 2009
- Subjects: Instant messaging , Mobile communication systems , Data transmission systems
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9774 , http://hdl.handle.net/10948/877 , Instant messaging , Mobile communication systems , Data transmission systems
- Description: Instant Messaging (IM) is becoming increasingly popular in social as well as workplace environments. In fact, many employees use the same IM client to communicate with both colleagues and social contacts. Thus, there are valid concerns about the impact of IM on employee productivity. One of the major advantages of IM over other workplace communication tools such as e-mail and the telephone is the implementation of presence information. In particular, presence awareness is used to determine the avail- ability and willingness of a contact to engage in communication. A current problem with IM is the one-for-all approach to presence: all contacts receive the same set of presence information. However, presence is rooted in social psychology where it is known that the awareness of another person changes the behavior of oneself. Therefore the identity of a contact affects the availability and willingness directed towards that contact. In order for presence information to be provided to contacts, it must be represented in some type of data format. The Internet Engineering Task Force (IETF) has done much work in standardizing IM and presence systems. In particular their data format for presence describes a rich set of presence information including, but not limited to, location, activity, awareness, and mood information. Such information may be sensitive and access to it needs to be controlled to ensure privacy. As with access control policies, managing the information as the number of contacts increases becomes cumbersome and complex. This dissertation draws on the theoretical foundations of presence, current standards in the domain of IM, and lessons from access control to present an enhanced presence handling model for IM. The model is developed in stages, with each stage providing a specific improvement. The first stage of the model is grounded on the current work of the IETF. As such it distributes presence on a per-watcher basis. In the second stage of the model watchers fulfill a specific role and based on this role they receive only the entrusted presence information. In practice, it implies that a "friend" may get more (or less) information than a "colleague". The third stage of the model introduces the concept of availability profiles by drawing on social awareness principles. Availability profiles add the ability to transform presence and change the presentity's behavior to incoming messages according to the provided presence information. Finally the dissertation reports on the development of the RoBIM (Role- Based Instant Messenger) prototype. RoBIM is a standards-based IM system that conforms to the IETF SIMPLE protocol and provides various standard IM features. Here, RoBIM serves as a proof-of-concept for the proposed model. This study contributed to the domain of IM and presence by addressing some of the current presence handling issues. Most importantly, the proposed model takes into account the interpersonal effects of individualizing presence information for different contacts. Thus, the model challenges conventional thought and implementation of presence in IM.
- Full Text:
- Date Issued: 2009
- Authors: Victor, Rudi
- Date: 2009
- Subjects: Instant messaging , Mobile communication systems , Data transmission systems
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9774 , http://hdl.handle.net/10948/877 , Instant messaging , Mobile communication systems , Data transmission systems
- Description: Instant Messaging (IM) is becoming increasingly popular in social as well as workplace environments. In fact, many employees use the same IM client to communicate with both colleagues and social contacts. Thus, there are valid concerns about the impact of IM on employee productivity. One of the major advantages of IM over other workplace communication tools such as e-mail and the telephone is the implementation of presence information. In particular, presence awareness is used to determine the avail- ability and willingness of a contact to engage in communication. A current problem with IM is the one-for-all approach to presence: all contacts receive the same set of presence information. However, presence is rooted in social psychology where it is known that the awareness of another person changes the behavior of oneself. Therefore the identity of a contact affects the availability and willingness directed towards that contact. In order for presence information to be provided to contacts, it must be represented in some type of data format. The Internet Engineering Task Force (IETF) has done much work in standardizing IM and presence systems. In particular their data format for presence describes a rich set of presence information including, but not limited to, location, activity, awareness, and mood information. Such information may be sensitive and access to it needs to be controlled to ensure privacy. As with access control policies, managing the information as the number of contacts increases becomes cumbersome and complex. This dissertation draws on the theoretical foundations of presence, current standards in the domain of IM, and lessons from access control to present an enhanced presence handling model for IM. The model is developed in stages, with each stage providing a specific improvement. The first stage of the model is grounded on the current work of the IETF. As such it distributes presence on a per-watcher basis. In the second stage of the model watchers fulfill a specific role and based on this role they receive only the entrusted presence information. In practice, it implies that a "friend" may get more (or less) information than a "colleague". The third stage of the model introduces the concept of availability profiles by drawing on social awareness principles. Availability profiles add the ability to transform presence and change the presentity's behavior to incoming messages according to the provided presence information. Finally the dissertation reports on the development of the RoBIM (Role- Based Instant Messenger) prototype. RoBIM is a standards-based IM system that conforms to the IETF SIMPLE protocol and provides various standard IM features. Here, RoBIM serves as a proof-of-concept for the proposed model. This study contributed to the domain of IM and presence by addressing some of the current presence handling issues. Most importantly, the proposed model takes into account the interpersonal effects of individualizing presence information for different contacts. Thus, the model challenges conventional thought and implementation of presence in IM.
- Full Text:
- Date Issued: 2009
Enabling e-learning 2.0 in information security education: a semantic web approach
- Authors: Goss, Ryan Gavin
- Date: 2009
- Subjects: Data protection , Computers -- Access control , Electronic data processing -- Security measures , Electronic data processing departments -- Security measures
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9771 , http://hdl.handle.net/10948/909 , Data protection , Computers -- Access control , Electronic data processing -- Security measures , Electronic data processing departments -- Security measures
- Description: The motivation for this study argued that current information security ed- ucation systems are inadequate for educating all users of computer systems world wide in acting securely during their operations with information sys- tems. There is, therefore, a pervasive need for information security knowledge in all aspects of modern life. E-Learning 2.0 could possi- bly contribute to solving this problem, however, little or no knowledge currently exists regarding the suitability and practicality of using such systems to infer information security knowledge to learners.
- Full Text:
- Date Issued: 2009
- Authors: Goss, Ryan Gavin
- Date: 2009
- Subjects: Data protection , Computers -- Access control , Electronic data processing -- Security measures , Electronic data processing departments -- Security measures
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9771 , http://hdl.handle.net/10948/909 , Data protection , Computers -- Access control , Electronic data processing -- Security measures , Electronic data processing departments -- Security measures
- Description: The motivation for this study argued that current information security ed- ucation systems are inadequate for educating all users of computer systems world wide in acting securely during their operations with information sys- tems. There is, therefore, a pervasive need for information security knowledge in all aspects of modern life. E-Learning 2.0 could possi- bly contribute to solving this problem, however, little or no knowledge currently exists regarding the suitability and practicality of using such systems to infer information security knowledge to learners.
- Full Text:
- Date Issued: 2009
An enterprise information security model for a micro finance company: a case study
- Authors: Owen, Morné
- Date: 2009
- Subjects: Computer security -- South Africa -- Management , Computers -- Access control -- South Africa , Computer networks -- Security measures -- Standards -- South Africa , Data protection -- Management -- Standards , Management information systems -- Security measures -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9763 , http://hdl.handle.net/10948/1151 , Computer security -- South Africa -- Management , Computers -- Access control -- South Africa , Computer networks -- Security measures -- Standards -- South Africa , Data protection -- Management -- Standards , Management information systems -- Security measures -- South Africa
- Description: The world has entered the information age. How the information is used within an organization will determine success or failure of the organisation. This study aims to provide a model, that once implemented, will provide the required protection for the information assets. The model is based on ISO 27002, an international security standard. The primary objective is to build a model that will provide a holistic security system specifically for a South African Micro Finance Company (MFC). The secondary objectives focuses on successful implementation of such a model, the uniqueness of the MFC that should be taken into account, and the maintenance of the model once implemented to ensure ongoing relevance. A questionnaire conducted at the MFC provided insight into the perceived understanding of information security. The questionnaire results were used to ensure the model solution addressed current information security shortcomings within the MFC. This study found that the information security controls in ISO 27002 should be applicable to any industry. The uniqueness for the MFC is not in the security controls, but rather in the regulations and laws applicable to it.
- Full Text:
- Date Issued: 2009
- Authors: Owen, Morné
- Date: 2009
- Subjects: Computer security -- South Africa -- Management , Computers -- Access control -- South Africa , Computer networks -- Security measures -- Standards -- South Africa , Data protection -- Management -- Standards , Management information systems -- Security measures -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9763 , http://hdl.handle.net/10948/1151 , Computer security -- South Africa -- Management , Computers -- Access control -- South Africa , Computer networks -- Security measures -- Standards -- South Africa , Data protection -- Management -- Standards , Management information systems -- Security measures -- South Africa
- Description: The world has entered the information age. How the information is used within an organization will determine success or failure of the organisation. This study aims to provide a model, that once implemented, will provide the required protection for the information assets. The model is based on ISO 27002, an international security standard. The primary objective is to build a model that will provide a holistic security system specifically for a South African Micro Finance Company (MFC). The secondary objectives focuses on successful implementation of such a model, the uniqueness of the MFC that should be taken into account, and the maintenance of the model once implemented to ensure ongoing relevance. A questionnaire conducted at the MFC provided insight into the perceived understanding of information security. The questionnaire results were used to ensure the model solution addressed current information security shortcomings within the MFC. This study found that the information security controls in ISO 27002 should be applicable to any industry. The uniqueness for the MFC is not in the security controls, but rather in the regulations and laws applicable to it.
- Full Text:
- Date Issued: 2009
Civil engineering components for a conceptual elevated light rail transit model with reference to Nelson Mandela Bay
- Authors: Zang, Jin
- Date: 2009
- Subjects: Railroads, Local and light -- South Africa -- Port Elizabeth , Street-railroads -- South Africa -- Port Elizabeth , Local transit -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9593 , http://hdl.handle.net/10948/769 , Railroads, Local and light -- South Africa -- Port Elizabeth , Street-railroads -- South Africa -- Port Elizabeth , Local transit -- South Africa -- Port Elizabeth
- Description: The increase of motor vehicles, especially in cities, cause transport problems of traffic congestion, vehicle accidents, air pollution and a lack of public spaces. The increasing number of motor vehicles consumes huge amounts of finite petrol energy and emits large amounts of gases that are harmful to the atmosphere and the natural environment. Therefore, the current road transport network is not a sustainable form of public transport for the future. In order to seek a suitable transportation mode, the Infrastructure and Engineering Business Unit of the Nelson Mandela Bay Municipality (NMBM) did some feasibility studies about light rail transit (LRT) from 1984 to 1988. The NMBM-report (1988: 8) concluded that a LRT system would provide the most suitable and primary mode to serve Nelson Mandela Bay (NMB). Although LRT was regarded as the most suitable primary mode of transport at that time (1988), further studies that were reported in 2006 recommended an alternative public transportation system. This research refers to these studies done for the NMB area and other studies and reports for other areas, but focus on the identification of the most suitable civil engineering components for a conceptual elevated light rail transit (ELRT) model. Electrical driven LRT systems have advantages over internal-combustion driven vehicles in terms of environmental protection. Traditional LRT systems are at ground level and are integrated with the existing road network. Some successful LRT systems indicate that the success of LRT systems is mainly dependent on integration with the existing road network. However, the integration of road transport systems with LRT systems cause increased congestion and accidents. An ELRT system can solve these problems. Bangkok has already built an ELRT system to solve its severe traffic congestion. 4 In order to develop a conceptual ELRT model, this research aimed to determine the most suitable civil engineering components for a conceptual ELRT model, including: (i) the most suitable type of bridge foundation; (ii) the most suitable type bridge girder; (iii) the most suitable type of sleeper; and (iv) whether the track should be a ballasted or non-ballasted type. The grounded theory approach was adopted to build up sets of data from which the most suitable components could be selected. In addition, design analyses were done of the various types of components to determine their suitability for a conceptual ELRT model. Experienced engineers and experts were also consulted to identify the most suitable components. After analyses and selection of the most suitable components, outstanding experts were approached to evaluate the components that showed up as the most suitable through the research. The research results indicated that bored and cast-in-place piles, a double-cell trapezoidal segmental box girder, and twin-block sleepers on a non-ballasted sleeper bed are the most suitable civil engineering components.
- Full Text:
- Date Issued: 2009
- Authors: Zang, Jin
- Date: 2009
- Subjects: Railroads, Local and light -- South Africa -- Port Elizabeth , Street-railroads -- South Africa -- Port Elizabeth , Local transit -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9593 , http://hdl.handle.net/10948/769 , Railroads, Local and light -- South Africa -- Port Elizabeth , Street-railroads -- South Africa -- Port Elizabeth , Local transit -- South Africa -- Port Elizabeth
- Description: The increase of motor vehicles, especially in cities, cause transport problems of traffic congestion, vehicle accidents, air pollution and a lack of public spaces. The increasing number of motor vehicles consumes huge amounts of finite petrol energy and emits large amounts of gases that are harmful to the atmosphere and the natural environment. Therefore, the current road transport network is not a sustainable form of public transport for the future. In order to seek a suitable transportation mode, the Infrastructure and Engineering Business Unit of the Nelson Mandela Bay Municipality (NMBM) did some feasibility studies about light rail transit (LRT) from 1984 to 1988. The NMBM-report (1988: 8) concluded that a LRT system would provide the most suitable and primary mode to serve Nelson Mandela Bay (NMB). Although LRT was regarded as the most suitable primary mode of transport at that time (1988), further studies that were reported in 2006 recommended an alternative public transportation system. This research refers to these studies done for the NMB area and other studies and reports for other areas, but focus on the identification of the most suitable civil engineering components for a conceptual elevated light rail transit (ELRT) model. Electrical driven LRT systems have advantages over internal-combustion driven vehicles in terms of environmental protection. Traditional LRT systems are at ground level and are integrated with the existing road network. Some successful LRT systems indicate that the success of LRT systems is mainly dependent on integration with the existing road network. However, the integration of road transport systems with LRT systems cause increased congestion and accidents. An ELRT system can solve these problems. Bangkok has already built an ELRT system to solve its severe traffic congestion. 4 In order to develop a conceptual ELRT model, this research aimed to determine the most suitable civil engineering components for a conceptual ELRT model, including: (i) the most suitable type of bridge foundation; (ii) the most suitable type bridge girder; (iii) the most suitable type of sleeper; and (iv) whether the track should be a ballasted or non-ballasted type. The grounded theory approach was adopted to build up sets of data from which the most suitable components could be selected. In addition, design analyses were done of the various types of components to determine their suitability for a conceptual ELRT model. Experienced engineers and experts were also consulted to identify the most suitable components. After analyses and selection of the most suitable components, outstanding experts were approached to evaluate the components that showed up as the most suitable through the research. The research results indicated that bored and cast-in-place piles, a double-cell trapezoidal segmental box girder, and twin-block sleepers on a non-ballasted sleeper bed are the most suitable civil engineering components.
- Full Text:
- Date Issued: 2009
Size and other determinants of capital structure in South African manufacturing listed companies
- Authors: Mgudlwa, Nosipho
- Date: 2009
- Subjects: Capital management and capital structure , Capital , Corporations -- South Africa -- Finance , Business enterprises
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8941 , http://hdl.handle.net/10948/1192 , Capital management and capital structure , Capital , Corporations -- South Africa -- Finance , Business enterprises
- Description: The importance of the capital structure as a measure of company growth and performance has been at the core of vigorous debate for many years. With the threat of the recession and global competitiveness to the survival of organizations, what constitutes an optimal capital structure had to be interrogated. The focus of the study is to investigate the factors (with more emphasis on size) that influence the capital structure of manufacturing firms in general and South African manufacturing firms in particular. The aim is to advance recommendations on policy formulation so as to improve the financial performance of the manufacturing sector in South Africa, a developing economy. The study is explained within the theoretical framework which relates elements purported to have an influence on the capital structure to the use of leverage/debt by organizations. Leverage is seen to increase the shareholders‟ interest whilst being exposed to financial risk. The size of the organizations as a comparative element defines the extent of accessing the borrowed funds, hence the distinction between the Small, Medium and Micro Enterprises (SMMEs) and large sized enterprises (LSEs). The research evidence indicates that SMMEs are characterized by lower liquidity, use more short-term debt instead of use of long-term debt, and are generally low in debt and basically capital intensive. On the contrary LSEs are highly leveraged. The selected research design is triangulated, with a combination of a case study which is of a qualitative and interpretive nature, as well as a quantitative type survey by means of a structured questionnaire. Twenty five ratios were computed from information derived from the financial statements of organizations and means and medians were determined for comparative reasons. The questions were directed to chief financial officers or managers responsible for the compilation of the financial statements, mainly to expand on the debt policy of iv their respective organizations. The findings confirmed the correlation between gearing and size, asset structure and growth with the exception of profitability. On the relevance of financial policy regarding debt, two factors were proven to be influential to capital structure decisions: the theory and practice of capital structure and the impact of the debt policy, both of which relate to financial flexibility. The study concluded that as much as there are similarities/consistencies between the two size groups, there are fundamental differences confirming that size significantly impacts on the capital structure choice specifically the use of debt. It is, therefore, recommended that the South African government should review its policies with regards to the financial support towards SMME viability.
- Full Text:
- Date Issued: 2009
- Authors: Mgudlwa, Nosipho
- Date: 2009
- Subjects: Capital management and capital structure , Capital , Corporations -- South Africa -- Finance , Business enterprises
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8941 , http://hdl.handle.net/10948/1192 , Capital management and capital structure , Capital , Corporations -- South Africa -- Finance , Business enterprises
- Description: The importance of the capital structure as a measure of company growth and performance has been at the core of vigorous debate for many years. With the threat of the recession and global competitiveness to the survival of organizations, what constitutes an optimal capital structure had to be interrogated. The focus of the study is to investigate the factors (with more emphasis on size) that influence the capital structure of manufacturing firms in general and South African manufacturing firms in particular. The aim is to advance recommendations on policy formulation so as to improve the financial performance of the manufacturing sector in South Africa, a developing economy. The study is explained within the theoretical framework which relates elements purported to have an influence on the capital structure to the use of leverage/debt by organizations. Leverage is seen to increase the shareholders‟ interest whilst being exposed to financial risk. The size of the organizations as a comparative element defines the extent of accessing the borrowed funds, hence the distinction between the Small, Medium and Micro Enterprises (SMMEs) and large sized enterprises (LSEs). The research evidence indicates that SMMEs are characterized by lower liquidity, use more short-term debt instead of use of long-term debt, and are generally low in debt and basically capital intensive. On the contrary LSEs are highly leveraged. The selected research design is triangulated, with a combination of a case study which is of a qualitative and interpretive nature, as well as a quantitative type survey by means of a structured questionnaire. Twenty five ratios were computed from information derived from the financial statements of organizations and means and medians were determined for comparative reasons. The questions were directed to chief financial officers or managers responsible for the compilation of the financial statements, mainly to expand on the debt policy of iv their respective organizations. The findings confirmed the correlation between gearing and size, asset structure and growth with the exception of profitability. On the relevance of financial policy regarding debt, two factors were proven to be influential to capital structure decisions: the theory and practice of capital structure and the impact of the debt policy, both of which relate to financial flexibility. The study concluded that as much as there are similarities/consistencies between the two size groups, there are fundamental differences confirming that size significantly impacts on the capital structure choice specifically the use of debt. It is, therefore, recommended that the South African government should review its policies with regards to the financial support towards SMME viability.
- Full Text:
- Date Issued: 2009
Development of flexible automotive measurement adaptors for the PQ25 VWSA platform
- Authors: Pretorius, Shaun
- Date: 2009
- Subjects: Automobiles -- Measurement , Optical measurements
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9626 , http://hdl.handle.net/10948/1632 , http://hdl.handle.net/10948/d1011725 , Automobiles -- Measurement , Optical measurements
- Description: The following work describes all knowledge required in the creation of new automotive optical Photogrammetrical adaptors, which allow the user thereof to measure a fully assembled vehicle in its natural position, i.e. on its wheels for the PQ25 platform at Volkswagen of South Africa. The system is the only method available to the manufacturing plant to measure a fully assembled vehicle in this manner. The FlexMess system allows for a quick portable measurement of a vehicle at all stages of Vehicle manufacturing, aligned via the Volkswagen RPS standards. In the first part of the work, the problem of establishing a system capable of measuring the PQ25 platform is achieved by redesigning the PQ24 platform (previous generation Polo) to the new PQ25 vehicle platform. Once the system was redesigned a prototype adaptor system was created. In the second part of the work, the redesigned adaptor system is checked for its accuracy and repeatability. In a statistical analysis of the adaptors ability to measure the reference points needed for alignment of a vehicle, the system is compared to a CMM and verified that the limits fall within the limits of the original FlexMesśs certified accuracy limits. The last part of the work looks at addressing some of the problems of the FlexMess system by creating concepts for an ideal future FlexMess adaptor system.
- Full Text:
- Date Issued: 2009
- Authors: Pretorius, Shaun
- Date: 2009
- Subjects: Automobiles -- Measurement , Optical measurements
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9626 , http://hdl.handle.net/10948/1632 , http://hdl.handle.net/10948/d1011725 , Automobiles -- Measurement , Optical measurements
- Description: The following work describes all knowledge required in the creation of new automotive optical Photogrammetrical adaptors, which allow the user thereof to measure a fully assembled vehicle in its natural position, i.e. on its wheels for the PQ25 platform at Volkswagen of South Africa. The system is the only method available to the manufacturing plant to measure a fully assembled vehicle in this manner. The FlexMess system allows for a quick portable measurement of a vehicle at all stages of Vehicle manufacturing, aligned via the Volkswagen RPS standards. In the first part of the work, the problem of establishing a system capable of measuring the PQ25 platform is achieved by redesigning the PQ24 platform (previous generation Polo) to the new PQ25 vehicle platform. Once the system was redesigned a prototype adaptor system was created. In the second part of the work, the redesigned adaptor system is checked for its accuracy and repeatability. In a statistical analysis of the adaptors ability to measure the reference points needed for alignment of a vehicle, the system is compared to a CMM and verified that the limits fall within the limits of the original FlexMesśs certified accuracy limits. The last part of the work looks at addressing some of the problems of the FlexMess system by creating concepts for an ideal future FlexMess adaptor system.
- Full Text:
- Date Issued: 2009
Biological activities of medicinal plants traditionally used to treat Septicaemia in the Eastern Cape, South Africa
- Authors: Chinyama, Robert Fred
- Date: 2009
- Subjects: Materia medica, Vegetable -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Herbs -- Therapeutic use -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10119 , http://hdl.handle.net/10948/1274 , Materia medica, Vegetable -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Herbs -- Therapeutic use -- South Africa -- Eastern Cape
- Description: Over the past 25 years, there has been a resurgence of worldwide scientific research in the fields of ethnopharmacology. The Western world has acknowledged the continued use of traditional medicines by the majority of third world countries, and the need for novel drug development. Hence, much of the pharmaceutical research in recent years has focused on the ethnobotanical approach to drug discovery (Light et al., 2005). In South Africa, as in most developing parts of the world, traditional herbal medicine still forms the backbone of rural healthcare. The government health services in South Africa provide only western medical care although the majority of the population consult traditional healers for some or all of their healthcare needs (McGaw et al., 2005). Medicinal plants like Harpephyllum caffrum are used as blood purifiers or emetics (Watt and Breyer-Brandwijk, 1962), and also for treating acne and eczema. The antimicrobial activity of this plant can be used to treat septicaemia, which is ranked the sixth leading cause of death among neonates and the eighth leading cause of death for infants through the first year of life (Heron, 2007). In this study, the plants investigated for antimicrobial activity were Harpephyllum caffrum, Hermannia cuneifolia, Chironia baccifera, Rhigozum obovatum, Felicia muricata and Pentzia incana. These plants were tested against ATTC (American Type Culture Collection) strains and microorganisms isolated from clinical isolates of patients suffering from septicaemia. The assay methods used included the agar diffusion method using the Mast multipoint inoculator, the microtitre dilution method were used to determine the minimum inhibitory concentration, thin layer chromatography fingerprints accompanied by bioautographic assay were used to detect the inhibition of bacterial growth by active compounds separated from plant extracts and the Ames test was required to assess the possibility of bacterial mutagenesis upon the exposure to plant extracts which can lead to carcinogenicity. In agar diffusion method, extracts of Harpephyllum caffrum inhibited nine strains of Candida albicans, three species of Acinetobacter and four strains of E.faecalis. Extracts of Hermannia cuneifolia inhibited four strains of B.cereus and three strains of Staphylococcus aureus. Extracts of Chironia baccifera inhibited one strain of Acinetobacter and five strains of E.faecalis. Extracts of plants Rhigozum obovatum, Felicia muricata, and Pentzia incana showed no antimicrobial activity. In the microtitre dilution method used to determine the minimum inhibitory concentration (MIC), the results were different from the agar diffusion method. More activity was observed. Extracts of Harpephyllum caffrum inhibited three strains of E.coli, six strains of S.aureus, three species of Acinetobacter and one strain of Klebsiella pneumonia. Extracts of Hermannia cuneifolia inhibited four strains of B.cereus, three strains of S.aureus, two strains of K.oxytoca and one species of Acinetobacter. Extracts of Chironia baccifera inhibited three strains of S.aureus, one strain of MRSA, one species of Acinetobacter and one strain of S.haemolyticus. The MIC values ranged from 0.049 to 6.25mg/ml. Using the thin layer chromatography fingerprints, bioautography showed the presence of various inhibitory chemical compounds. Methanol and acetone extracts of Harpephyllum caffrum, separated very well and showed various inhibition zones on exposure to Candida albicans, Enterococcus faecalis and Staphylococcus aureus. The different inhibition zones were recorded as Rf In the Ames test (Maron and Ames, 1983) the methanol and acetone extracts of Harpephyllum caffrum and Hermannia cuneifolia were negative which means they were devoid of any mutagenic properties. Methanol extracts of Harpephyllum caffrum showed similar results in the Ames assay as reported by Verschaeve and Van Staden (2008). values ranging from 0.25 to 0.95. The zones indicate the different inhibiting chemical compounds present in the plant. Petroleum ether, ethyl acetate, chloroform and formic acid were the solvents used in the assay in the ratio 8:7:5:1, respectively. Establishing the antimicrobial activity of these plants contribute to the systematic scientific investigation of indigenous South African medicinal plants.
- Full Text:
- Date Issued: 2009
- Authors: Chinyama, Robert Fred
- Date: 2009
- Subjects: Materia medica, Vegetable -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Herbs -- Therapeutic use -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10119 , http://hdl.handle.net/10948/1274 , Materia medica, Vegetable -- South Africa -- Eastern Cape , Medicinal plants -- South Africa -- Eastern Cape , Traditional medicine -- South Africa -- Eastern Cape , Herbs -- Therapeutic use -- South Africa -- Eastern Cape
- Description: Over the past 25 years, there has been a resurgence of worldwide scientific research in the fields of ethnopharmacology. The Western world has acknowledged the continued use of traditional medicines by the majority of third world countries, and the need for novel drug development. Hence, much of the pharmaceutical research in recent years has focused on the ethnobotanical approach to drug discovery (Light et al., 2005). In South Africa, as in most developing parts of the world, traditional herbal medicine still forms the backbone of rural healthcare. The government health services in South Africa provide only western medical care although the majority of the population consult traditional healers for some or all of their healthcare needs (McGaw et al., 2005). Medicinal plants like Harpephyllum caffrum are used as blood purifiers or emetics (Watt and Breyer-Brandwijk, 1962), and also for treating acne and eczema. The antimicrobial activity of this plant can be used to treat septicaemia, which is ranked the sixth leading cause of death among neonates and the eighth leading cause of death for infants through the first year of life (Heron, 2007). In this study, the plants investigated for antimicrobial activity were Harpephyllum caffrum, Hermannia cuneifolia, Chironia baccifera, Rhigozum obovatum, Felicia muricata and Pentzia incana. These plants were tested against ATTC (American Type Culture Collection) strains and microorganisms isolated from clinical isolates of patients suffering from septicaemia. The assay methods used included the agar diffusion method using the Mast multipoint inoculator, the microtitre dilution method were used to determine the minimum inhibitory concentration, thin layer chromatography fingerprints accompanied by bioautographic assay were used to detect the inhibition of bacterial growth by active compounds separated from plant extracts and the Ames test was required to assess the possibility of bacterial mutagenesis upon the exposure to plant extracts which can lead to carcinogenicity. In agar diffusion method, extracts of Harpephyllum caffrum inhibited nine strains of Candida albicans, three species of Acinetobacter and four strains of E.faecalis. Extracts of Hermannia cuneifolia inhibited four strains of B.cereus and three strains of Staphylococcus aureus. Extracts of Chironia baccifera inhibited one strain of Acinetobacter and five strains of E.faecalis. Extracts of plants Rhigozum obovatum, Felicia muricata, and Pentzia incana showed no antimicrobial activity. In the microtitre dilution method used to determine the minimum inhibitory concentration (MIC), the results were different from the agar diffusion method. More activity was observed. Extracts of Harpephyllum caffrum inhibited three strains of E.coli, six strains of S.aureus, three species of Acinetobacter and one strain of Klebsiella pneumonia. Extracts of Hermannia cuneifolia inhibited four strains of B.cereus, three strains of S.aureus, two strains of K.oxytoca and one species of Acinetobacter. Extracts of Chironia baccifera inhibited three strains of S.aureus, one strain of MRSA, one species of Acinetobacter and one strain of S.haemolyticus. The MIC values ranged from 0.049 to 6.25mg/ml. Using the thin layer chromatography fingerprints, bioautography showed the presence of various inhibitory chemical compounds. Methanol and acetone extracts of Harpephyllum caffrum, separated very well and showed various inhibition zones on exposure to Candida albicans, Enterococcus faecalis and Staphylococcus aureus. The different inhibition zones were recorded as Rf In the Ames test (Maron and Ames, 1983) the methanol and acetone extracts of Harpephyllum caffrum and Hermannia cuneifolia were negative which means they were devoid of any mutagenic properties. Methanol extracts of Harpephyllum caffrum showed similar results in the Ames assay as reported by Verschaeve and Van Staden (2008). values ranging from 0.25 to 0.95. The zones indicate the different inhibiting chemical compounds present in the plant. Petroleum ether, ethyl acetate, chloroform and formic acid were the solvents used in the assay in the ratio 8:7:5:1, respectively. Establishing the antimicrobial activity of these plants contribute to the systematic scientific investigation of indigenous South African medicinal plants.
- Full Text:
- Date Issued: 2009
Investigation and prediction of autoignition during hot start conditions
- Authors: Wodausch, Jens
- Date: 2009
- Subjects: Automobiles -- Ignition
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9621 , http://hdl.handle.net/10948/991 , Automobiles -- Ignition
- Description: This Master’s thesis discusses the investigation of autoignition (knock) of air-fuel mixtures in internal combustion engines (type EA 827; 1.6 and 1.4 l) under hot start conditions. Chapter Three comprehensively reviews literature on fuel characteristics; specifically boiling point, chemistry and the difference between the Research and Motor Octane Number (RON and MON). Furthermore different types of autoignition are discussed with regards to their detection and assessment in the chapter. The subsection on engine management looks at possible methods of altering and eliminating autoignition. Chapter Four details the equipment used to obtain data and measurements, as well as the signal conditioning of the spark and injector signal. Chapter Five discusses the actual results obtained during summer testing of the different methods of altering and eliminating autoignition in an internal combustion engine, as derived from the theories presented in Chapter Three. The summer tests finally verified the new application level and showed that only a reduction in the quantity of fuel injected can eliminate autoignition. However, a slight decrease in heat release does cause an increase in start time. In Chapter Six, based on the test results, a simulation model which calculates the probability of autoignition in a 1.4 l (Econo) engine during hot start conditions in Matlab/Simulink was developed. This simulation model satisfactorily verified test results.
- Full Text:
- Date Issued: 2009
- Authors: Wodausch, Jens
- Date: 2009
- Subjects: Automobiles -- Ignition
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9621 , http://hdl.handle.net/10948/991 , Automobiles -- Ignition
- Description: This Master’s thesis discusses the investigation of autoignition (knock) of air-fuel mixtures in internal combustion engines (type EA 827; 1.6 and 1.4 l) under hot start conditions. Chapter Three comprehensively reviews literature on fuel characteristics; specifically boiling point, chemistry and the difference between the Research and Motor Octane Number (RON and MON). Furthermore different types of autoignition are discussed with regards to their detection and assessment in the chapter. The subsection on engine management looks at possible methods of altering and eliminating autoignition. Chapter Four details the equipment used to obtain data and measurements, as well as the signal conditioning of the spark and injector signal. Chapter Five discusses the actual results obtained during summer testing of the different methods of altering and eliminating autoignition in an internal combustion engine, as derived from the theories presented in Chapter Three. The summer tests finally verified the new application level and showed that only a reduction in the quantity of fuel injected can eliminate autoignition. However, a slight decrease in heat release does cause an increase in start time. In Chapter Six, based on the test results, a simulation model which calculates the probability of autoignition in a 1.4 l (Econo) engine during hot start conditions in Matlab/Simulink was developed. This simulation model satisfactorily verified test results.
- Full Text:
- Date Issued: 2009
Optimizing the recovery rate of Mycobacterium species from gastric lavages in children at an urban Zambian hospital
- Authors: Lubasi, David
- Date: 2009
- Subjects: Mycobacterium , Tuberculosis in children -- Diagnosis -- Zambia
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10118 , http://hdl.handle.net/10948/1440 , Mycobacterium , Tuberculosis in children -- Diagnosis -- Zambia
- Description: Tuberculosis (TB) has re-emerged as a major worldwide public health hazard with increasing incidence among adults and children. Although cases among children represent a small percentage of all TB cases, they are a reservoir from which many adult cases will arise. Estimates indicate that 9 million people develop TB annually, out of which 1 million (11 percent) occur in children less than 15 years old. Childhood tuberculosis is on the increase worldwide because of persisting inability to conform the diagnosis, leading to a large number of children dying of undiagnosed tuberculosis. Diagnosis of pulmonary tuberculosis has depended on bacteriological examination of sputum. In most of the developing countries sputum smear microscopy has been used as it has been found to be cheap and relative efficient. As a result of the high TB burden, there is an urgent need for improved methods of laboratory diagnosis of TB. This is especially needed in children were diagnosis is more challenging as mycobacteria is being detected in fewer than 50 percent of the cases. Children cannot produce adequate sputum samples for examination. Their sputum samples, if produced, has a low bacterial yield and making detection of mycobacteria by using the smear microscopy difficult. Therefore, gastric lavages from children are being recommended as the best specimen for culture. In this study, gastric lavages from 408 children suspected of having tuberculosis were examined for the recovery of mycobacteria. Recovery was optimized by the use of the relatively new non-radiometric fully automated BACTEC MGIT 960. BACTEC MGIT 960 produced a positivity rate of 27.2 percent against 17.2 percent that of Lowenstein-Jensen (L-J) media, which is a conventional culture method used widely. The direct microscopy which is the cheapest traditional method used in diagnosis of tuberculosis (TB) yielded a 5.6 percent positive rate. The BACTEC MGIT 960 had also a very high isolate detection rate of 98.2 percent compared to that of L-J media of 61.9 percent, and only 20.4 percent were detected with the direct microscopy. On time taken to detection or mean time to detection (TTD) of v isolates, the BACTEC MGIT 960 technique had a shorter mean time to detection, 12.5 days as compared to 34.3 days shown by the L-J media technique. The study showed that children normally get tuberculosis from adult members of the household. A positive TB case was found in the households of 55.4 percent of the suspects. The study has found that 46.4 percent of the children below the age of 4 years developed the disease, compared to 10.5 percent the older children in the age group 10 to 14 years. The study found that tuberculosis in children is mainly caused by Mycobacterium tuberculosis. Out of the 113 isolates detected, 110 (97.3 percent) were M. tuberculosis. The remaining 2.7 percent were the non-tuberculous M. avium complex and M. kansasii. It was inconclusive whether the 2.7 percent of other species were causing tuberculosis and this need to be studied further.
- Full Text:
- Date Issued: 2009
- Authors: Lubasi, David
- Date: 2009
- Subjects: Mycobacterium , Tuberculosis in children -- Diagnosis -- Zambia
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10118 , http://hdl.handle.net/10948/1440 , Mycobacterium , Tuberculosis in children -- Diagnosis -- Zambia
- Description: Tuberculosis (TB) has re-emerged as a major worldwide public health hazard with increasing incidence among adults and children. Although cases among children represent a small percentage of all TB cases, they are a reservoir from which many adult cases will arise. Estimates indicate that 9 million people develop TB annually, out of which 1 million (11 percent) occur in children less than 15 years old. Childhood tuberculosis is on the increase worldwide because of persisting inability to conform the diagnosis, leading to a large number of children dying of undiagnosed tuberculosis. Diagnosis of pulmonary tuberculosis has depended on bacteriological examination of sputum. In most of the developing countries sputum smear microscopy has been used as it has been found to be cheap and relative efficient. As a result of the high TB burden, there is an urgent need for improved methods of laboratory diagnosis of TB. This is especially needed in children were diagnosis is more challenging as mycobacteria is being detected in fewer than 50 percent of the cases. Children cannot produce adequate sputum samples for examination. Their sputum samples, if produced, has a low bacterial yield and making detection of mycobacteria by using the smear microscopy difficult. Therefore, gastric lavages from children are being recommended as the best specimen for culture. In this study, gastric lavages from 408 children suspected of having tuberculosis were examined for the recovery of mycobacteria. Recovery was optimized by the use of the relatively new non-radiometric fully automated BACTEC MGIT 960. BACTEC MGIT 960 produced a positivity rate of 27.2 percent against 17.2 percent that of Lowenstein-Jensen (L-J) media, which is a conventional culture method used widely. The direct microscopy which is the cheapest traditional method used in diagnosis of tuberculosis (TB) yielded a 5.6 percent positive rate. The BACTEC MGIT 960 had also a very high isolate detection rate of 98.2 percent compared to that of L-J media of 61.9 percent, and only 20.4 percent were detected with the direct microscopy. On time taken to detection or mean time to detection (TTD) of v isolates, the BACTEC MGIT 960 technique had a shorter mean time to detection, 12.5 days as compared to 34.3 days shown by the L-J media technique. The study showed that children normally get tuberculosis from adult members of the household. A positive TB case was found in the households of 55.4 percent of the suspects. The study has found that 46.4 percent of the children below the age of 4 years developed the disease, compared to 10.5 percent the older children in the age group 10 to 14 years. The study found that tuberculosis in children is mainly caused by Mycobacterium tuberculosis. Out of the 113 isolates detected, 110 (97.3 percent) were M. tuberculosis. The remaining 2.7 percent were the non-tuberculous M. avium complex and M. kansasii. It was inconclusive whether the 2.7 percent of other species were causing tuberculosis and this need to be studied further.
- Full Text:
- Date Issued: 2009
Development of biological control strategies against sirex noctilio (Fabricius) on Sappi Forests (Ltd) Landholdings in the summer rainfall regions of South Africa
- Authors: Verleur, Peter Marcel
- Date: 2009
- Subjects: Pests -- Biological control -- South Africa , Nonindigenous pests -- Control
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10741 , http://hdl.handle.net/10948/1273 , Pests -- Biological control -- South Africa , Nonindigenous pests -- Control
- Description: The commercial forest industry in South Africa is predominantly dependent on large tracts of exotic monoculture plantations. While this simplifies management practice, there is always the inherent danger posed by introduced pests and diseases. Classical biological control is usually the most effective control method against introduced exotic pests. Climatic factors and seasonal differences may negatively affect the ability of the natural enemies to establish successfully at the new location. Successful establishment of the natural enemies usually results in control over the pest within four years. Sirex noctilio naturally occurs in the mediterranean countries of Europe and North Africa. It is the only member of the Siricid family capable of killing living pine trees. Sirex noctilio was accidentally introduced into New Zealand from Europe during the early 1900s. It has since been found in Australia, Brazil, Argentina South Africa and Chile. Initial biological control in New Zealand and Tasmania was through the release of Siricid specific parasitoid wasps from Europe and North America. The discovery of the accidental introduction of the entomophagous nematode Beddingia siricidicola and its subsequent artificial culturing for release provided the platform for the biological control methodology, which brought the Sirex woodwasp under control. The methods and natural enemies used in New Zealand and Australia were introduced by the South American countries and in the Western Cape of South Africa. Successful biological control was achieved in the Western Cape within two years after the initial introduction of the nematode B. siricidicola. The migration of S. noctilio into the summer rainfall regions of South Africa occurred in the absence of the associated natural enemies. This resulted in rapid population growth of the pest and substantial damage was caused to plantations of Pinus patula in the Eastern Cape and KwaZulu-Natal. Initial attempts at introducing B. siricidicola during 2004 were not very successful. This study contributes to the understanding and adaptation of the biological control methods to the summer rainfall climate. The key finding was that in the summer rainfall climate, only the bottom third of nematode inoculated S. noctilio infested trees produced parasitized adults during the emergence period. A comparative study was done on log samples from S. noctilio infested trees collected in the Western Cape and KwaZulu-Natal. iv An adapted nematode inoculation technique for pulpwood plantations in the summer rainfall regions was developed and implemented in mass inoculations with B. siricidicola during 2007 and 2008. Locally available herbicides were tested for suitability of use in the establishment of trap trees, which would attract ovipositing S. noctilio females in situations where low numbers of the woodwasp occur. Determination of the levels of natural B. siricidicola parasitism in S. noctilio adults during the 2008 emergence period indicate successful establishment of the nematode in KwaZulu-Natal. Successful introduction of the parasitoid wasp Ibalia leucospoides into the summer rainfall regions has also been achieved.
- Full Text:
- Date Issued: 2009
- Authors: Verleur, Peter Marcel
- Date: 2009
- Subjects: Pests -- Biological control -- South Africa , Nonindigenous pests -- Control
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10741 , http://hdl.handle.net/10948/1273 , Pests -- Biological control -- South Africa , Nonindigenous pests -- Control
- Description: The commercial forest industry in South Africa is predominantly dependent on large tracts of exotic monoculture plantations. While this simplifies management practice, there is always the inherent danger posed by introduced pests and diseases. Classical biological control is usually the most effective control method against introduced exotic pests. Climatic factors and seasonal differences may negatively affect the ability of the natural enemies to establish successfully at the new location. Successful establishment of the natural enemies usually results in control over the pest within four years. Sirex noctilio naturally occurs in the mediterranean countries of Europe and North Africa. It is the only member of the Siricid family capable of killing living pine trees. Sirex noctilio was accidentally introduced into New Zealand from Europe during the early 1900s. It has since been found in Australia, Brazil, Argentina South Africa and Chile. Initial biological control in New Zealand and Tasmania was through the release of Siricid specific parasitoid wasps from Europe and North America. The discovery of the accidental introduction of the entomophagous nematode Beddingia siricidicola and its subsequent artificial culturing for release provided the platform for the biological control methodology, which brought the Sirex woodwasp under control. The methods and natural enemies used in New Zealand and Australia were introduced by the South American countries and in the Western Cape of South Africa. Successful biological control was achieved in the Western Cape within two years after the initial introduction of the nematode B. siricidicola. The migration of S. noctilio into the summer rainfall regions of South Africa occurred in the absence of the associated natural enemies. This resulted in rapid population growth of the pest and substantial damage was caused to plantations of Pinus patula in the Eastern Cape and KwaZulu-Natal. Initial attempts at introducing B. siricidicola during 2004 were not very successful. This study contributes to the understanding and adaptation of the biological control methods to the summer rainfall climate. The key finding was that in the summer rainfall climate, only the bottom third of nematode inoculated S. noctilio infested trees produced parasitized adults during the emergence period. A comparative study was done on log samples from S. noctilio infested trees collected in the Western Cape and KwaZulu-Natal. iv An adapted nematode inoculation technique for pulpwood plantations in the summer rainfall regions was developed and implemented in mass inoculations with B. siricidicola during 2007 and 2008. Locally available herbicides were tested for suitability of use in the establishment of trap trees, which would attract ovipositing S. noctilio females in situations where low numbers of the woodwasp occur. Determination of the levels of natural B. siricidicola parasitism in S. noctilio adults during the 2008 emergence period indicate successful establishment of the nematode in KwaZulu-Natal. Successful introduction of the parasitoid wasp Ibalia leucospoides into the summer rainfall regions has also been achieved.
- Full Text:
- Date Issued: 2009
Precooling strategies for passenger vehicles
- Wachsmuth, Carsten Ulrich Harro
- Authors: Wachsmuth, Carsten Ulrich Harro
- Date: 2009
- Subjects: Automobiles -- Air conditioning , Air conditioning
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9643 , http://hdl.handle.net/10948/930 , Automobiles -- Air conditioning , Air conditioning
- Description: By ventilating the vehicle’s interior during a soak, the peak cooling load is reduced and therefore the air-conditioning needs less power. This in turn translates to a smaller air-conditioning unit which would consume less power, be lighter and more compact. This solar driven ventilation of the vehicle’s interior during a soak is defined as precooling. During this project the best precooling strategy for passenger vehicles was found by investigating and testing different precooling strategies and evaluating them according to their thermodynamic performance, their potential implementation and their influence on the required cooling performance of the airconditioning cycle. The best performances were achieved by strategies with a high air flow rate and a relatively low air inlet temperature. Two categories of precooling strategies were examined: natural convection and forced convection strategies. Openings in the vehicle’s body that fit to all strategies had to be found; with a big potential concerning their thermodynamic performance and other aspects like prevention against water penetration. The best investigated precooling strategies proved to be the one which used the design outlet as an inlet and the opening of the HVAC as an outlet. With these openings a good air flow through the whole cabin can be guaranteed. In addition to that the strategy only uses existing openings of the body which prevent against water penetration. The required installation space for this strategy already exists and can be considered for the package of next generation vehicles.
- Full Text:
- Date Issued: 2009
- Authors: Wachsmuth, Carsten Ulrich Harro
- Date: 2009
- Subjects: Automobiles -- Air conditioning , Air conditioning
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9643 , http://hdl.handle.net/10948/930 , Automobiles -- Air conditioning , Air conditioning
- Description: By ventilating the vehicle’s interior during a soak, the peak cooling load is reduced and therefore the air-conditioning needs less power. This in turn translates to a smaller air-conditioning unit which would consume less power, be lighter and more compact. This solar driven ventilation of the vehicle’s interior during a soak is defined as precooling. During this project the best precooling strategy for passenger vehicles was found by investigating and testing different precooling strategies and evaluating them according to their thermodynamic performance, their potential implementation and their influence on the required cooling performance of the airconditioning cycle. The best performances were achieved by strategies with a high air flow rate and a relatively low air inlet temperature. Two categories of precooling strategies were examined: natural convection and forced convection strategies. Openings in the vehicle’s body that fit to all strategies had to be found; with a big potential concerning their thermodynamic performance and other aspects like prevention against water penetration. The best investigated precooling strategies proved to be the one which used the design outlet as an inlet and the opening of the HVAC as an outlet. With these openings a good air flow through the whole cabin can be guaranteed. In addition to that the strategy only uses existing openings of the body which prevent against water penetration. The required installation space for this strategy already exists and can be considered for the package of next generation vehicles.
- Full Text:
- Date Issued: 2009
A framework for the secure use of portable storage devices : a South African higher education perspective
- Authors: Rothman, Jonathan Sean
- Date: 2009
- Subjects: Computer storage devices , Computer storage devices -- Management , Education, Higher -- Computer network resources
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9766 , http://hdl.handle.net/10948/1054 , Computer storage devices , Computer storage devices -- Management , Education, Higher -- Computer network resources
- Description: South African Higher Education has gone through various changes and challenges, one of these being the merger process. Various Universities and Technikons were forced to merge in an effort to aid the transformation and restructuring of the Higher Education landscape in the post-apartheid era. From an ICT point of view, the merged Institutions ended up with massive and distributed computing facilities. These facilities must be managed and secured and it can be appreciated that the complexity and magnitude of this task is compounded by the large and varied user population (i.e. students) using the facilities. With the exploding use of mobile consumer devices (such as cell phones, personal digital assistants, MP3 players, portable storage devices such as flash drives, etc), Higher Education Institutions are faced with the even more complex task of managing and securing the computing infrastructure, while large numbers of students can enter computer labs and use these devices at random. In some circles, portable devices are touted to be the next panacea in higher education. This, together with the popularity these devices enjoy under the student body, makes it a fait accompli that mobile consumer devices are “here to stay”. Therefore, banning these devices from campus computer labs, is not viable. Universities have to find ways to address security issues through the implementation of appropriate protective measures. This research focuses on finding a solution to mitigating the risks imposed on Higher Education Institutions in South Africa caused by the use of portable storage devices. The research proposes a framework which serves as an outline for the countermeasures that Universities must implement to mitigate the risks inherent to the use of portable storage devices. The scope of the research is limited to flash drives, smart phones and MP3 players.
- Full Text:
- Date Issued: 2009
- Authors: Rothman, Jonathan Sean
- Date: 2009
- Subjects: Computer storage devices , Computer storage devices -- Management , Education, Higher -- Computer network resources
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9766 , http://hdl.handle.net/10948/1054 , Computer storage devices , Computer storage devices -- Management , Education, Higher -- Computer network resources
- Description: South African Higher Education has gone through various changes and challenges, one of these being the merger process. Various Universities and Technikons were forced to merge in an effort to aid the transformation and restructuring of the Higher Education landscape in the post-apartheid era. From an ICT point of view, the merged Institutions ended up with massive and distributed computing facilities. These facilities must be managed and secured and it can be appreciated that the complexity and magnitude of this task is compounded by the large and varied user population (i.e. students) using the facilities. With the exploding use of mobile consumer devices (such as cell phones, personal digital assistants, MP3 players, portable storage devices such as flash drives, etc), Higher Education Institutions are faced with the even more complex task of managing and securing the computing infrastructure, while large numbers of students can enter computer labs and use these devices at random. In some circles, portable devices are touted to be the next panacea in higher education. This, together with the popularity these devices enjoy under the student body, makes it a fait accompli that mobile consumer devices are “here to stay”. Therefore, banning these devices from campus computer labs, is not viable. Universities have to find ways to address security issues through the implementation of appropriate protective measures. This research focuses on finding a solution to mitigating the risks imposed on Higher Education Institutions in South Africa caused by the use of portable storage devices. The research proposes a framework which serves as an outline for the countermeasures that Universities must implement to mitigate the risks inherent to the use of portable storage devices. The scope of the research is limited to flash drives, smart phones and MP3 players.
- Full Text:
- Date Issued: 2009
Investigating the use of the ITIL framework towards IT services delivery at the NMMU
- Authors: Lubambo, Nontobeko
- Date: 2009
- Subjects: Information technology -- Management , Management information systems , Computer industry -- Customer services -- Management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9767 , http://hdl.handle.net/10948/1001 , http://hdl.handle.net/10948/d1009657 , Information technology -- Management , Management information systems , Computer industry -- Customer services -- Management
- Description: The purpose of this research was to investigate what is involved in IT Service Management and how the NMMU can implement it to improve the quality of IT service support and service delivery. The IT Service Management approach was investigated but the main focus was on the Service Support and Service Delivery in the ITIL framework. Higher Education was analyzed to try and measure the maturity level of the ITIL process implementation to see where Higher Education in South Africa is and to determine the gaps. Findings from the empirical study will be presented and recommendations highlighted to Top management and the IT department in order to promote and improve the quality of the IT service being delivered to users and customers. The data was collected and administered by means of a structured questionnaire based on the ITIL Service Capacity Maturity Model and Rick Leopoldi’s alternative Maturity Assessment method. An Association of South African University Directors of Information Technology (ASAUDIT) questionnaire on Service Management was also used to supplement the questionnaire. It was discovered that the implementation of ITIL in most organizations brought about improvements and benefits in the quality of the IT service being delivered.
- Full Text:
- Date Issued: 2009
- Authors: Lubambo, Nontobeko
- Date: 2009
- Subjects: Information technology -- Management , Management information systems , Computer industry -- Customer services -- Management
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9767 , http://hdl.handle.net/10948/1001 , http://hdl.handle.net/10948/d1009657 , Information technology -- Management , Management information systems , Computer industry -- Customer services -- Management
- Description: The purpose of this research was to investigate what is involved in IT Service Management and how the NMMU can implement it to improve the quality of IT service support and service delivery. The IT Service Management approach was investigated but the main focus was on the Service Support and Service Delivery in the ITIL framework. Higher Education was analyzed to try and measure the maturity level of the ITIL process implementation to see where Higher Education in South Africa is and to determine the gaps. Findings from the empirical study will be presented and recommendations highlighted to Top management and the IT department in order to promote and improve the quality of the IT service being delivered to users and customers. The data was collected and administered by means of a structured questionnaire based on the ITIL Service Capacity Maturity Model and Rick Leopoldi’s alternative Maturity Assessment method. An Association of South African University Directors of Information Technology (ASAUDIT) questionnaire on Service Management was also used to supplement the questionnaire. It was discovered that the implementation of ITIL in most organizations brought about improvements and benefits in the quality of the IT service being delivered.
- Full Text:
- Date Issued: 2009