Managerial perceptions of corporate social responsibility and social practices present at McDonalds South Africa
- Authors: Böckle, Ingrid
- Date: 2009
- Subjects: Social responsibility of business -- South Africa -- Case studies , Business ethics -- South Africa -- Case studies , Management -- Moral and ethical aspects -- South Africa -- Case studies , Executives -- Professional ethics -- South Africa -- Case studies , Corporate governance -- Moral and ethical aspects -- South Africa -- Case studies , Business logistics -- Moral and ethical aspects -- South Africa -- Case studies , McDonald's Corporation
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3300 , http://hdl.handle.net/10962/d1003088
- Description: This study deals with corporate social responsibility (CSR) and focuses on managerial perceptions of CSR at McDonald’s South Africa (SA) and how social responsibility is translated into social practices. The key objectives of the research are: to analyse McDonald’s both internationally and locally in South Africa to establish whether CSR policies exist, then to investigate how these policies are perceived and integrated by outlet managers. Lastly to investigate what kind of social responsibility (SR) involvement, if at all, occurs at outlet level. The research site covers three regions in South Africa, which are the Eastern Cape, Western Cape and Gauteng. The total research sample is 38. 33 interviewees were outlet managers, who were purposively selected, and 5 additional interviews took place with: 2 McDonald’s SA Head Office representatives, 2 interviews with beneficiaries of McDonald’s SR involvement and 1 with the trade union SACCAWU. The research was carried out through questionnaires and semi-structured interviews. The design of this research is based on an interpretive social science approach. The aim of the research was to investigate outlet managers’ perceptions of CSR and social practices present at McDonald’s SA outlets. The key findings of the research indicate that: CSR policies at McDonald’s SA head office are not communicated sufficiently to outlet managers, SR involvement is evident, especially for initiatives focusing on children’s welfare, but far too little occurs at the outlet level. There are also too few checks on social involvement by head office and no formal reporting system is available to the outlets except through an internal magazine, called the Big Mag. There is no official CSR report at McDonald’s SA. The fact that no report exists makes this study more relevant since this research investigates matters pertaining to CSR and social practices. The overall significance of the study is that it brings to the forefront the importance of internal company and external broader regulation which is part of the greater debate of CSR. This is because the analysis of managerial perceptions and implementation of CSR shows some unwarranted discrepancies between policies and practices, locally, nationally and internationally even within the same organisation.
- Full Text:
- Date Issued: 2009
- Authors: Böckle, Ingrid
- Date: 2009
- Subjects: Social responsibility of business -- South Africa -- Case studies , Business ethics -- South Africa -- Case studies , Management -- Moral and ethical aspects -- South Africa -- Case studies , Executives -- Professional ethics -- South Africa -- Case studies , Corporate governance -- Moral and ethical aspects -- South Africa -- Case studies , Business logistics -- Moral and ethical aspects -- South Africa -- Case studies , McDonald's Corporation
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:3300 , http://hdl.handle.net/10962/d1003088
- Description: This study deals with corporate social responsibility (CSR) and focuses on managerial perceptions of CSR at McDonald’s South Africa (SA) and how social responsibility is translated into social practices. The key objectives of the research are: to analyse McDonald’s both internationally and locally in South Africa to establish whether CSR policies exist, then to investigate how these policies are perceived and integrated by outlet managers. Lastly to investigate what kind of social responsibility (SR) involvement, if at all, occurs at outlet level. The research site covers three regions in South Africa, which are the Eastern Cape, Western Cape and Gauteng. The total research sample is 38. 33 interviewees were outlet managers, who were purposively selected, and 5 additional interviews took place with: 2 McDonald’s SA Head Office representatives, 2 interviews with beneficiaries of McDonald’s SR involvement and 1 with the trade union SACCAWU. The research was carried out through questionnaires and semi-structured interviews. The design of this research is based on an interpretive social science approach. The aim of the research was to investigate outlet managers’ perceptions of CSR and social practices present at McDonald’s SA outlets. The key findings of the research indicate that: CSR policies at McDonald’s SA head office are not communicated sufficiently to outlet managers, SR involvement is evident, especially for initiatives focusing on children’s welfare, but far too little occurs at the outlet level. There are also too few checks on social involvement by head office and no formal reporting system is available to the outlets except through an internal magazine, called the Big Mag. There is no official CSR report at McDonald’s SA. The fact that no report exists makes this study more relevant since this research investigates matters pertaining to CSR and social practices. The overall significance of the study is that it brings to the forefront the importance of internal company and external broader regulation which is part of the greater debate of CSR. This is because the analysis of managerial perceptions and implementation of CSR shows some unwarranted discrepancies between policies and practices, locally, nationally and internationally even within the same organisation.
- Full Text:
- Date Issued: 2009
Managing leader member exchange frequency effectively in a South African retail company
- Viljoen, Petrus Johannes Jacobus
- Authors: Viljoen, Petrus Johannes Jacobus
- Date: 2009
- Subjects: Communication in organizations -- South Africa , Communication in management -- South Africa , Leadership -- South Africa , Organizational behavior -- South Africa , Organizational effectiveness -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8692 , http://hdl.handle.net/10948/1106 , Communication in organizations -- South Africa , Communication in management -- South Africa , Leadership -- South Africa , Organizational behavior -- South Africa , Organizational effectiveness -- South Africa
- Description: The purpose of this research is to highlight the importance of identifying the communication frequency within the leader-member exchange (LMX) relationship, and to appreciate what the positive or negative effect of a low or high LMX frequency has on this relationship and on staff morale. Management is for the most part responsible for communication frequency and is in a position and has the means to change such frequency or to add additional communication channels. The research was based on a program introduced in a South African retail company three years ago. Data was collected from 64 stores in the Western Cape and the results were statistically analysed on the SPSS16 program. The results clearly supported the hypotheses that, in a low-communication frequency area, an increase in communication frequency has a positive effect on staff morale and that the proximity to head office (or lack of it) does not have a negative effect on staff morale.
- Full Text:
- Date Issued: 2009
- Authors: Viljoen, Petrus Johannes Jacobus
- Date: 2009
- Subjects: Communication in organizations -- South Africa , Communication in management -- South Africa , Leadership -- South Africa , Organizational behavior -- South Africa , Organizational effectiveness -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8692 , http://hdl.handle.net/10948/1106 , Communication in organizations -- South Africa , Communication in management -- South Africa , Leadership -- South Africa , Organizational behavior -- South Africa , Organizational effectiveness -- South Africa
- Description: The purpose of this research is to highlight the importance of identifying the communication frequency within the leader-member exchange (LMX) relationship, and to appreciate what the positive or negative effect of a low or high LMX frequency has on this relationship and on staff morale. Management is for the most part responsible for communication frequency and is in a position and has the means to change such frequency or to add additional communication channels. The research was based on a program introduced in a South African retail company three years ago. Data was collected from 64 stores in the Western Cape and the results were statistically analysed on the SPSS16 program. The results clearly supported the hypotheses that, in a low-communication frequency area, an increase in communication frequency has a positive effect on staff morale and that the proximity to head office (or lack of it) does not have a negative effect on staff morale.
- Full Text:
- Date Issued: 2009
Manicured
- Authors: Knowles, Corinne R
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , poem
- Identifier: http://hdl.handle.net/10962/468895 , vital:77139 , ISBN 0028-4459 , https://journals.co.za/doi/epdf/10.10520/EJC47808
- Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
- Full Text:
- Date Issued: 2009
- Authors: Knowles, Corinne R
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , poem
- Identifier: http://hdl.handle.net/10962/468895 , vital:77139 , ISBN 0028-4459 , https://journals.co.za/doi/epdf/10.10520/EJC47808
- Description: New Coin is one of South Africa's most established and influential poetry journals. It publishes poetry, and poetry-related reviews, commentary and interviews. New Coin places a particular emphasis on evolving forms and experimental use of the English language in poetry in the South African context. In this sense it has traced the most exciting trends and currents in contemporary poetry in South Africa for a decade of more. The journal is published twice a year in June and December by the Institute for the Study of English in Africa (ISEA), Rhodes University.
- Full Text:
- Date Issued: 2009
Mariculture as a means to add value to the east coast rock lobster Panulirus homarus rubellus subsistence fishery : a physiological approach to define transport and growout protocols for wild caught juveniles
- Authors: Kemp, Justin Oliver Gordon
- Date: 2009
- Subjects: Lobster fisheries -- South Africa , Lobster culture -- South Africa , Lobsters -- Growth -- South Africa , Mariculture -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5299 , http://hdl.handle.net/10962/d1005144
- Description: In a context of declining capture fisheries and public pressure for greater access to marine resources, marine aquaculture is receiving increasing interest from the South African government as a means to increase the diversity of economic activities in coastal regions, thereby providing employment and reducing poverty. The east coast rock lobster Panulirus homarus rubellus is currently harvested by subsistence fisherman along the former Transkei coastline of south-east South Africa and presents a possible opportunity for ongrowing wild juvenile lobsters in culture facilities. Lack of compliance coupled with poor enforcement of the minimum size limit (65 mm carapace length) has resulted in the ongoing harvest of undersize size lobsters by subsistence fishers. Generally, fishers either consume these undersize lobsters or sell them to tourists for low prices. In line with international trends in rock lobster aquaculture, interest has subsequently arisen in the possibilities of ongrowing these undersize lobsters as a means of adding value to the P. h rubellus resource for subsistence fishers. The aim of this physiological study was to assess the biological feasibility of harvesting, transporting and culturing wild caught juvenile lobsters, thereby provide empirical data to inform the development of suitable transport and culture protocols. The experimental objectives were to asses the effect of temperature on growth and survival of P. h. rubellus, as well as the effects of a suite of extrinsic and intrinsic factors on ammonia excretion and oxygen consumption. Juvenile lobsters were collected by hand from near-shore reefs (2-15 m depth) off Mdumbi in the former Transkei, Eastern Cape Province and transported by road (7 hours) to the Port Alfred Marine Research Laboratory where they were held in a recirculating culture system. The effect of temperature over a range of 9.7 °C (18.9±0.7 to 28.6±1.5 °C) on the growth and survival of juvenile P. h. rubellus fed a diet of fresh mussel flesh was investigated. Specific growth rate (SGR) was significantly different between temperatures (p = 0.01), with the highest values recorded for the 24 °C and 28 °C treatments. There was no significant difference in moult increment (MI) between temperatures, however, intermoult period (IMP) differed significantly between temperatures (p = 0.0015) with mean IMP lowest at 24 °C, although not significantly different from the means of the 26 °C and 28 °C treatments. IMP was highest at 19 °C and 21 °C. Apparent feed intake was significantly different between treatments (p < 0.0001) and exhibited a strong positive correlation with increasing temperature. Food conversion ratio (FCR) differed significantly between temperatures (p = 0.02) with 24 °C exhibiting the most efficient FCR. The results for growth rate and food conversion efficiency suggested that 24 °C is optimal for the growout of juvenile P. h. rubellus. In the second study, the effect of body weight, emersion, daily rhythm, feeding and ambient ammonia on the total ammonia nitrogen (TAN) excretion rate was investigated. Body weight (n = 16, range of 16.8 – 322 g) was positively correlated to daytime TAN excretion rate (mg h⁻¹). Re-immersion after one hour emersion in a moist environment was characterized by a significant increase in TAN excretion rate for the first hour compared to pre-immersion levels. The amount of TAN excreted during this period was as expected if basal TAN excretion rates were maintained during emersion. TAN excretion rates returned to pre-emersion levels by the end of the second hour. There was no evidence of a daily rhythm in TAN excretion rate for P. h. rubellus. TAN excretion rates were elevated following feeding. An initial peak in TAN excretion rate after seven hours (7.58 times pre-feeding rate) was followed by a smaller peak after 13 hours (6.69 times pre-feeding rate). TAN excretion rate dropped to levels not significantly different from pre-feeding levels after 23 hours and consistently returned to pre-feeding levels after 42 hours. The TAN excretion rates of lobster exposed for two hours to an ambient TAN concentration of 1.02±0.10 mg l⁻¹ and 2.3± 0.2 mg l⁻¹ were not significantly different from TAN excretion rates recorded at low ambient water TAN prior to exposure. Exposure to an ambient TAN concentration of 4.45±0.78 mg l⁻¹ had a significant effect on the TAN excretion rate, with pronounced ammonia uptake occurring for all animals at this concentration. The third study investigated the effects of body weight, diurnal rhythm, feeding and emersion on lobster oxygen consumption. Body weight was positively correlated to both standard and active oxygen consumption (mg O2 h⁻¹) while body weight was negatively correlated to mass-specific standard oxygen uptake (mg O2 g⁻¹ h⁻¹). Diurnal rhythm exhibited a strong effect on the lobsters oxygen consumption, with average night time values 67% greater than those recorded during the day. This was related to activity driven by intrinsic nocturnal foraging behaviour. Feeding resulted in a classic specific dynamic action (SDA) response, with postprandial oxygen consumption increasing to a peak before decreasing gradually to preprandial levels. Emersion resulted in a significant increase in oxygen consumption, with lobsters rapidly recovering to pre-emersion levels after four hours. Results from these studies suggest that the capture, transport and culture of juvenile P. h. rubellus is biologically feasible. Empirical data generated were used to provide recommendations regarding species optimised transport and culture protocols. A purge time of 48 hours before transport is suggested to ensure that ammonia excretion and oxygen consumption are at basal levels. Furthermore, emersed transport for a period of one hour is characterised by rapid recovery upon re-immersion. In order to prevent the accumulation of stressors, it is suggested that consecutive periods of emersion are interjected with recovery periods (five hours) in water to allow the removal of accumulated ammonia and repayment of the oxygen debt incurred. The recorded ammonia rates indicate that a biological filter size of 4.8 m³ is recommended for 1000 kg of fed lobsters in a culture situation, although this can be reduced considerably if lobsters are being held without feeding (0.72 m³). A flow rate of 112 l kg⁻¹ h⁻¹ is required to meet the metabolic requirements of lobsters. Bottlenecks to the viable commercial culture of P. h. rubellus, and the ability of this practice to provide the socio-economic benefits that were envisioned, are discussed.
- Full Text:
- Date Issued: 2009
- Authors: Kemp, Justin Oliver Gordon
- Date: 2009
- Subjects: Lobster fisheries -- South Africa , Lobster culture -- South Africa , Lobsters -- Growth -- South Africa , Mariculture -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5299 , http://hdl.handle.net/10962/d1005144
- Description: In a context of declining capture fisheries and public pressure for greater access to marine resources, marine aquaculture is receiving increasing interest from the South African government as a means to increase the diversity of economic activities in coastal regions, thereby providing employment and reducing poverty. The east coast rock lobster Panulirus homarus rubellus is currently harvested by subsistence fisherman along the former Transkei coastline of south-east South Africa and presents a possible opportunity for ongrowing wild juvenile lobsters in culture facilities. Lack of compliance coupled with poor enforcement of the minimum size limit (65 mm carapace length) has resulted in the ongoing harvest of undersize size lobsters by subsistence fishers. Generally, fishers either consume these undersize lobsters or sell them to tourists for low prices. In line with international trends in rock lobster aquaculture, interest has subsequently arisen in the possibilities of ongrowing these undersize lobsters as a means of adding value to the P. h rubellus resource for subsistence fishers. The aim of this physiological study was to assess the biological feasibility of harvesting, transporting and culturing wild caught juvenile lobsters, thereby provide empirical data to inform the development of suitable transport and culture protocols. The experimental objectives were to asses the effect of temperature on growth and survival of P. h. rubellus, as well as the effects of a suite of extrinsic and intrinsic factors on ammonia excretion and oxygen consumption. Juvenile lobsters were collected by hand from near-shore reefs (2-15 m depth) off Mdumbi in the former Transkei, Eastern Cape Province and transported by road (7 hours) to the Port Alfred Marine Research Laboratory where they were held in a recirculating culture system. The effect of temperature over a range of 9.7 °C (18.9±0.7 to 28.6±1.5 °C) on the growth and survival of juvenile P. h. rubellus fed a diet of fresh mussel flesh was investigated. Specific growth rate (SGR) was significantly different between temperatures (p = 0.01), with the highest values recorded for the 24 °C and 28 °C treatments. There was no significant difference in moult increment (MI) between temperatures, however, intermoult period (IMP) differed significantly between temperatures (p = 0.0015) with mean IMP lowest at 24 °C, although not significantly different from the means of the 26 °C and 28 °C treatments. IMP was highest at 19 °C and 21 °C. Apparent feed intake was significantly different between treatments (p < 0.0001) and exhibited a strong positive correlation with increasing temperature. Food conversion ratio (FCR) differed significantly between temperatures (p = 0.02) with 24 °C exhibiting the most efficient FCR. The results for growth rate and food conversion efficiency suggested that 24 °C is optimal for the growout of juvenile P. h. rubellus. In the second study, the effect of body weight, emersion, daily rhythm, feeding and ambient ammonia on the total ammonia nitrogen (TAN) excretion rate was investigated. Body weight (n = 16, range of 16.8 – 322 g) was positively correlated to daytime TAN excretion rate (mg h⁻¹). Re-immersion after one hour emersion in a moist environment was characterized by a significant increase in TAN excretion rate for the first hour compared to pre-immersion levels. The amount of TAN excreted during this period was as expected if basal TAN excretion rates were maintained during emersion. TAN excretion rates returned to pre-emersion levels by the end of the second hour. There was no evidence of a daily rhythm in TAN excretion rate for P. h. rubellus. TAN excretion rates were elevated following feeding. An initial peak in TAN excretion rate after seven hours (7.58 times pre-feeding rate) was followed by a smaller peak after 13 hours (6.69 times pre-feeding rate). TAN excretion rate dropped to levels not significantly different from pre-feeding levels after 23 hours and consistently returned to pre-feeding levels after 42 hours. The TAN excretion rates of lobster exposed for two hours to an ambient TAN concentration of 1.02±0.10 mg l⁻¹ and 2.3± 0.2 mg l⁻¹ were not significantly different from TAN excretion rates recorded at low ambient water TAN prior to exposure. Exposure to an ambient TAN concentration of 4.45±0.78 mg l⁻¹ had a significant effect on the TAN excretion rate, with pronounced ammonia uptake occurring for all animals at this concentration. The third study investigated the effects of body weight, diurnal rhythm, feeding and emersion on lobster oxygen consumption. Body weight was positively correlated to both standard and active oxygen consumption (mg O2 h⁻¹) while body weight was negatively correlated to mass-specific standard oxygen uptake (mg O2 g⁻¹ h⁻¹). Diurnal rhythm exhibited a strong effect on the lobsters oxygen consumption, with average night time values 67% greater than those recorded during the day. This was related to activity driven by intrinsic nocturnal foraging behaviour. Feeding resulted in a classic specific dynamic action (SDA) response, with postprandial oxygen consumption increasing to a peak before decreasing gradually to preprandial levels. Emersion resulted in a significant increase in oxygen consumption, with lobsters rapidly recovering to pre-emersion levels after four hours. Results from these studies suggest that the capture, transport and culture of juvenile P. h. rubellus is biologically feasible. Empirical data generated were used to provide recommendations regarding species optimised transport and culture protocols. A purge time of 48 hours before transport is suggested to ensure that ammonia excretion and oxygen consumption are at basal levels. Furthermore, emersed transport for a period of one hour is characterised by rapid recovery upon re-immersion. In order to prevent the accumulation of stressors, it is suggested that consecutive periods of emersion are interjected with recovery periods (five hours) in water to allow the removal of accumulated ammonia and repayment of the oxygen debt incurred. The recorded ammonia rates indicate that a biological filter size of 4.8 m³ is recommended for 1000 kg of fed lobsters in a culture situation, although this can be reduced considerably if lobsters are being held without feeding (0.72 m³). A flow rate of 112 l kg⁻¹ h⁻¹ is required to meet the metabolic requirements of lobsters. Bottlenecks to the viable commercial culture of P. h. rubellus, and the ability of this practice to provide the socio-economic benefits that were envisioned, are discussed.
- Full Text:
- Date Issued: 2009
Mathematical requirements for first-year BCOM students at NMMU
- Authors: Walton, Marguerite
- Date: 2009
- Subjects: Business mathematics -- South Africa , Mathematics -- Study and teaching (Higher) -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10502 , http://hdl.handle.net/10948/886 , Business mathematics -- South Africa , Mathematics -- Study and teaching (Higher) -- South Africa
- Description: These studies have focused on identifying the mathematical requirements of first-year BCom students at Nelson Mandela Metropolitan University. The research methodology used in this quantitative study was to make use of interviewing, questionnaire investigation, and document analysis in the form of textbook, test and examination analysis. These methods provided data that fitted into a grounded theory approach. The study concluded by identifying the list of mathematical topics required for the first year of the core subjects in the BCom degree programme. In addition, the study found that learners who study Mathematics in the National Senior Certificate should be able to cope with the mathematical content included in their BCom degree programme, while learners studying Mathematical Literacy would probably need support in some of the areas of mathematics, especially algebra, in order to cope with the mathematical content included in their BCom degree programme. It makes a valuable contribution towards elucidating the mathematical requirements needed to improve the chances of successful BCom degree programme studies at South African universities. It also draws the contours for starting to design an efficient support course for future “at-risk” students who enter higher education studies.
- Full Text:
- Date Issued: 2009
- Authors: Walton, Marguerite
- Date: 2009
- Subjects: Business mathematics -- South Africa , Mathematics -- Study and teaching (Higher) -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10502 , http://hdl.handle.net/10948/886 , Business mathematics -- South Africa , Mathematics -- Study and teaching (Higher) -- South Africa
- Description: These studies have focused on identifying the mathematical requirements of first-year BCom students at Nelson Mandela Metropolitan University. The research methodology used in this quantitative study was to make use of interviewing, questionnaire investigation, and document analysis in the form of textbook, test and examination analysis. These methods provided data that fitted into a grounded theory approach. The study concluded by identifying the list of mathematical topics required for the first year of the core subjects in the BCom degree programme. In addition, the study found that learners who study Mathematics in the National Senior Certificate should be able to cope with the mathematical content included in their BCom degree programme, while learners studying Mathematical Literacy would probably need support in some of the areas of mathematics, especially algebra, in order to cope with the mathematical content included in their BCom degree programme. It makes a valuable contribution towards elucidating the mathematical requirements needed to improve the chances of successful BCom degree programme studies at South African universities. It also draws the contours for starting to design an efficient support course for future “at-risk” students who enter higher education studies.
- Full Text:
- Date Issued: 2009
Meeting democracy’s challenge developments:
- Authors: Dugmore, Harry
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159389 , vital:40293 , https://hdl.handle.net/10520/EJC139935
- Description: In a context of declining public participation, can mobile phone technology and 'new media' be used to involve more people in local decision-making, asks Harry Dug more in this exploration of the implications of mobile communication on journalism in the developing world.
- Full Text:
- Date Issued: 2009
- Authors: Dugmore, Harry
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159389 , vital:40293 , https://hdl.handle.net/10520/EJC139935
- Description: In a context of declining public participation, can mobile phone technology and 'new media' be used to involve more people in local decision-making, asks Harry Dug more in this exploration of the implications of mobile communication on journalism in the developing world.
- Full Text:
- Date Issued: 2009
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
Metal (Co, Fe) tribenzotetraazachlorin–fullerene conjugates
- Ozoemena, Kenneth I, Mamuru, Solomon A, Fukuda, Takamitsu, Kobayashi, Nagao, Nyokong, Tebello
- Authors: Ozoemena, Kenneth I , Mamuru, Solomon A , Fukuda, Takamitsu , Kobayashi, Nagao , Nyokong, Tebello
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263464 , vital:53630 , xlink:href="https://doi.org/10.1016/j.elecom.2009.04.011"
- Description: Novel hexabutylsulphonyltribenzotetraazachlorin–fullerene (C60) complexes of iron (FeHBSTBTAC–C60) and cobalt (CoHBSTBTAC–C60) have been synthesized and their electrochemistry and oxygen reduction reaction (ORR) compared with their octabutylsulphonylphthalocyanine analogues (FeOBSPc and CoOBSPc). It is proved that electron-withdrawing substituents (–SO2Bu and C60) on phthalocyanine macrocycle exhibit distinct impact on the solution electrochemistry of these metallophthalocyanine (MPc) complexes. The more electron-withdrawing C60 substituent suppressed ORR compared to the –SO2Bu in alkaline medium. FeOBSPc showed the best ORR activity involving a direct 4-electron mechanism, a rate constant of ∼1 × 108 cm3 mol−1 s−1 and a Tafel slope of −171 mV dec−1.
- Full Text:
- Date Issued: 2009
- Authors: Ozoemena, Kenneth I , Mamuru, Solomon A , Fukuda, Takamitsu , Kobayashi, Nagao , Nyokong, Tebello
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263464 , vital:53630 , xlink:href="https://doi.org/10.1016/j.elecom.2009.04.011"
- Description: Novel hexabutylsulphonyltribenzotetraazachlorin–fullerene (C60) complexes of iron (FeHBSTBTAC–C60) and cobalt (CoHBSTBTAC–C60) have been synthesized and their electrochemistry and oxygen reduction reaction (ORR) compared with their octabutylsulphonylphthalocyanine analogues (FeOBSPc and CoOBSPc). It is proved that electron-withdrawing substituents (–SO2Bu and C60) on phthalocyanine macrocycle exhibit distinct impact on the solution electrochemistry of these metallophthalocyanine (MPc) complexes. The more electron-withdrawing C60 substituent suppressed ORR compared to the –SO2Bu in alkaline medium. FeOBSPc showed the best ORR activity involving a direct 4-electron mechanism, a rate constant of ∼1 × 108 cm3 mol−1 s−1 and a Tafel slope of −171 mV dec−1.
- Full Text:
- Date Issued: 2009
Metal-biomass interactions a comparison of visualisation techniques available in South Africa
- Moore, Beverly A, Mack, Cherie-Lynn, Duncan, John R, Burgess, Jo E
- Authors: Moore, Beverly A , Mack, Cherie-Lynn , Duncan, John R , Burgess, Jo E
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/480518 , vital:78451 , https://hdl.handle.net/10520/EJC96905
- Description: The interaction of metals and biological materials is of interest for reasons such as metal recovery, toxicity and production of high-value products such as gold and platinum nanoparticles. Understanding the way in which metals interact with the biomass surface and intracellular components provides insights into the biosorption and bioaccumulation processes and increases the potential for process optimisation. Three technologies are available for the qualitative visualisation of metal-biomass interactions in South Africa, namely, micro-PIXE, transmission electron microscopy and scanning electron microscopy coupled with energy-dispersive analysis of X-rays. Each technique provides unique information and has specific shortcomings which should be taken into account when selecting the appropriate technology. This paper focuses on evaluating the various techniques.
- Full Text:
- Date Issued: 2009
- Authors: Moore, Beverly A , Mack, Cherie-Lynn , Duncan, John R , Burgess, Jo E
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/480518 , vital:78451 , https://hdl.handle.net/10520/EJC96905
- Description: The interaction of metals and biological materials is of interest for reasons such as metal recovery, toxicity and production of high-value products such as gold and platinum nanoparticles. Understanding the way in which metals interact with the biomass surface and intracellular components provides insights into the biosorption and bioaccumulation processes and increases the potential for process optimisation. Three technologies are available for the qualitative visualisation of metal-biomass interactions in South Africa, namely, micro-PIXE, transmission electron microscopy and scanning electron microscopy coupled with energy-dispersive analysis of X-rays. Each technique provides unique information and has specific shortcomings which should be taken into account when selecting the appropriate technology. This paper focuses on evaluating the various techniques.
- Full Text:
- Date Issued: 2009
Metallophthalocyanine Based Carbon Paste Electrodes for the Determination of 2′, 3′‐Dideoxyinosine
- Ozoemena, Kenneth I, Stefan-van Staden, Raluca-Ioana, Nyokong, Tebello
- Authors: Ozoemena, Kenneth I , Stefan-van Staden, Raluca-Ioana , Nyokong, Tebello
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263430 , vital:53627 , xlink:href="https://doi.org/10.1002/elan.200904581"
- Description: Novel electrochemical sensors based on carbon paste impregnated with metallopthalocyanine (MPc, M=Co, Fe) complexes, have been constructed for the assay of anti-HIV drug 2′,3′-dideoxyinosine (didanosine, DDI). Both modified electrodes showed electrocatalytic activity towards the oxidation of dideoxyinosine in phosphate buffer pH 7.4 with a working concentration range of 10−6–10−4 mol/L and a detection limit of 10−7 mol/L magnitude order. The sensor proved to be highly reliable for the assay of the purity of DDI - raw material as well as for the uniformity content test of Videx tablets.
- Full Text:
- Date Issued: 2009
- Authors: Ozoemena, Kenneth I , Stefan-van Staden, Raluca-Ioana , Nyokong, Tebello
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263430 , vital:53627 , xlink:href="https://doi.org/10.1002/elan.200904581"
- Description: Novel electrochemical sensors based on carbon paste impregnated with metallopthalocyanine (MPc, M=Co, Fe) complexes, have been constructed for the assay of anti-HIV drug 2′,3′-dideoxyinosine (didanosine, DDI). Both modified electrodes showed electrocatalytic activity towards the oxidation of dideoxyinosine in phosphate buffer pH 7.4 with a working concentration range of 10−6–10−4 mol/L and a detection limit of 10−7 mol/L magnitude order. The sensor proved to be highly reliable for the assay of the purity of DDI - raw material as well as for the uniformity content test of Videx tablets.
- Full Text:
- Date Issued: 2009
Microsatellite markers for the roman, Chrysoblephus laticeps (Teleostei: Sparidae), an overexploited seabream from South Africa
- Teske, Peter R, Cowley, Paul D, Forget, Fabian R, Beheregaray, Luciano B
- Authors: Teske, Peter R , Cowley, Paul D , Forget, Fabian R , Beheregaray, Luciano B
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445690 , vital:74414 , https://doi.org/10.1111/j.1755-0998.2009.02595.x
- Description: Eleven polymorphic microsatellite loci were developed from an enrichment library of the roman, Chrysoblephus laticeps, and characterized for 40 individuals collected in Africa's largest and oldest Marine Protected Area (MPA), the Tsitsikamma National Park. The number of alleles per locus ranged from three to 19, and heterozygosities ranged from 0.20 to 0.85. A significant departure from Hardy–Weinberg equilibrium was detected for one locus, and linkage disequilibrium was identified among three pairs of loci. The markers will be useful to detect whether populations resident in MPAs along the South African coast are genetically connected, and whether there is spillover of recruits into adjacent exploited areas.
- Full Text:
- Date Issued: 2009
- Authors: Teske, Peter R , Cowley, Paul D , Forget, Fabian R , Beheregaray, Luciano B
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/445690 , vital:74414 , https://doi.org/10.1111/j.1755-0998.2009.02595.x
- Description: Eleven polymorphic microsatellite loci were developed from an enrichment library of the roman, Chrysoblephus laticeps, and characterized for 40 individuals collected in Africa's largest and oldest Marine Protected Area (MPA), the Tsitsikamma National Park. The number of alleles per locus ranged from three to 19, and heterozygosities ranged from 0.20 to 0.85. A significant departure from Hardy–Weinberg equilibrium was detected for one locus, and linkage disequilibrium was identified among three pairs of loci. The markers will be useful to detect whether populations resident in MPAs along the South African coast are genetically connected, and whether there is spillover of recruits into adjacent exploited areas.
- Full Text:
- Date Issued: 2009
Milk production and calf performance in Nguni and crossbred cattle raised on communal rangelands of the Eastern Cape province of South Africa
- Authors: Mapekula, Monde
- Date: 2009
- Subjects: Nguni cattle , Communal rangelands -- South Africa -- Eastern Cape , Dairy processing -- South Africa -- Eastern Cape , Milk yield -- South Africa -- Eastern Cape , Amino acids -- South Africa -- Eastern Cape , Fatty acids
- Language: English
- Type: Thesis , Doctoral , PhD (Animal Science)
- Identifier: vital:11813 , http://hdl.handle.net/10353/247 , Nguni cattle , Communal rangelands -- South Africa -- Eastern Cape , Dairy processing -- South Africa -- Eastern Cape , Milk yield -- South Africa -- Eastern Cape , Amino acids -- South Africa -- Eastern Cape , Fatty acids
- Description: Information on milk production could be useful in designing strategies that would help to improve milk production in communal farming systems. This study was conducted to determine milk production and calf performance of Nguni and crossbreds under smallholder cattle production conditions. Four trials were conducted in the study. The objective of the first trial was to determine farmer perceptions on milk production and calf rearing in smallholder areas. Data were obtained from 218 smallholder farmers, using a structured questionnaire. Smallholder farmer sector is constituted by small scale commercial farmers and communal farmers. Small-scale commercial farmers in South Africa obtained farms from the government through land claims or they bought the farms. Their farming background is a communal type. Communal farmers are farmers that are sharing the same grazing land and animals are managed according to the experience of the owner. The findings in this study indicated that there were numerous constraints to milk production in smallholder areas. These included lack of technical expertise and poor veterinary support services. The farmers also indicated that calf performance was low. The second trial was conducted to determine if there were differences in calf performance, gastrointestinal parasites and nutritionally-related blood metabolites between Nguni and crossbred calves. Body weights and faecal samples were collected monthly until weaning at six months. The levels of total protein, albumin, globulins, non-esterified fatty acids (NEFA), glucose, cholesterol and minerals were determined monthly. Nguni calves had higher birth weights than crossbreds (P<0.05). Average daily gain and weaning weights of Nguni calves were greater than crossbred calves (P<0.05. Nguni calves had lower total protein at early age after birth (P<0.05). However, at weaning Nguni calves had higher total protein than crossbreds (P<0.05). Nguni calves had higher levels of glucose and NEFA concentrations than crossbred calves (P<0.05). In the third trial, milk utilisation patterns in smallholder areas of the Eastern Cape were assessed. Cattle owners (n = 130) were randomly selected in three different regions to determine milk consumption patterns, milk sales, prices and factors influencing these activities. The information was gathered using milk recording sheets, which were administered in February (early lactation) and June (late lactation) in 2009. Milk consumption per household was similar among the three districts (P>0.05). Milk was utilised as both fresh and sour. Fresh milk was utilised with tea/coffee and porridge. Excess fresh milk was utilised to feed pets (mostly cats and puppies). The puppies were fed on mostly whey, and, at times, on fresh milk. Sour milk was utilised to prepare of umvubo (a mixture of sour milk and scrambled porridge (umphokoqo) or a mixture of sour milk and bread). In some cases, excess milk was given to neighbours as a form of social investment and fame. The quality of milk from Nguni and crossbred cows was compared in the fourth trial. Milk samples were evaluated for quality in early (February), mid (April) and late (June) lactation in 2009. The essential amino acids, non-essential amino acids and fatty acids were determined. Nguni milk had higher amino acids and fatty acids concentration than crossbreds (P<0.05). Nguni milk had higher arginine levels in the early and mid lactation periods compared to crossbred cows (P<0.05). Nguni milk had higher methionine and threonine levels than crossbred cows (P<0.05). Methionine levels in Nguni were 0.15, 0.19 and 0.18 in early, mid and late lactation while crossbred had 0.05, 0.05 and 0.06 (g/100ml), respectively. There were significant interactions between lactation stage and genotype for lysine levels with Nguni milk having higher (P<0.05) lysine levels in the mid and late lactation periods. Nguni cows had higher tyrosine, glycine and proline levels than crossbred cows (P<0.05). In the early lactation, Nguni cows had higher serine levels than crossbred cows (P<0.05). In mid lactation crossbred cows had higher serine levels than Nguni cows (P<0.05). There were significant differences between genotypes on fatty acid composition. Nguni milk had higher C12:0 levels than crossbreds (P<0.05). However, milk from crossbred cows had higher C14:0 levels than that for Nguni cows (P<0.05) and also had higher levels of C16:0 and C18:0 fatty acids compared to Nguni cows. Crossbred milk had higher levels of C18n1n9t in early lactation period than Nguni and decreased as the stage of lactation progressed (P<0.05). In the early lactation, the levels of C18n1nC in Nguni milk were higher (P<0.05) than in late lactation. In the mid and late lactation, crossbred cows milk had higher C18n1nC levels than in early lactation (P<0.05). Lactation stage and genotype affected saturated fatty, monounsaturated fatty acids, cis-fatty acids and omega 3 (n-3) to omega 6 (n-6). In general, Nguni milk had higher mineral composition than crossbred milk (P<0.05). In conclusion, Nguni calves performed better than crossbred calves under communal rangelands. There is a need for crossing Nguni cows with dairy breeds in commercial dairying by smalhoder farmers as a strategy for improving both milk quality and quantity.
- Full Text:
- Date Issued: 2009
- Authors: Mapekula, Monde
- Date: 2009
- Subjects: Nguni cattle , Communal rangelands -- South Africa -- Eastern Cape , Dairy processing -- South Africa -- Eastern Cape , Milk yield -- South Africa -- Eastern Cape , Amino acids -- South Africa -- Eastern Cape , Fatty acids
- Language: English
- Type: Thesis , Doctoral , PhD (Animal Science)
- Identifier: vital:11813 , http://hdl.handle.net/10353/247 , Nguni cattle , Communal rangelands -- South Africa -- Eastern Cape , Dairy processing -- South Africa -- Eastern Cape , Milk yield -- South Africa -- Eastern Cape , Amino acids -- South Africa -- Eastern Cape , Fatty acids
- Description: Information on milk production could be useful in designing strategies that would help to improve milk production in communal farming systems. This study was conducted to determine milk production and calf performance of Nguni and crossbreds under smallholder cattle production conditions. Four trials were conducted in the study. The objective of the first trial was to determine farmer perceptions on milk production and calf rearing in smallholder areas. Data were obtained from 218 smallholder farmers, using a structured questionnaire. Smallholder farmer sector is constituted by small scale commercial farmers and communal farmers. Small-scale commercial farmers in South Africa obtained farms from the government through land claims or they bought the farms. Their farming background is a communal type. Communal farmers are farmers that are sharing the same grazing land and animals are managed according to the experience of the owner. The findings in this study indicated that there were numerous constraints to milk production in smallholder areas. These included lack of technical expertise and poor veterinary support services. The farmers also indicated that calf performance was low. The second trial was conducted to determine if there were differences in calf performance, gastrointestinal parasites and nutritionally-related blood metabolites between Nguni and crossbred calves. Body weights and faecal samples were collected monthly until weaning at six months. The levels of total protein, albumin, globulins, non-esterified fatty acids (NEFA), glucose, cholesterol and minerals were determined monthly. Nguni calves had higher birth weights than crossbreds (P<0.05). Average daily gain and weaning weights of Nguni calves were greater than crossbred calves (P<0.05. Nguni calves had lower total protein at early age after birth (P<0.05). However, at weaning Nguni calves had higher total protein than crossbreds (P<0.05). Nguni calves had higher levels of glucose and NEFA concentrations than crossbred calves (P<0.05). In the third trial, milk utilisation patterns in smallholder areas of the Eastern Cape were assessed. Cattle owners (n = 130) were randomly selected in three different regions to determine milk consumption patterns, milk sales, prices and factors influencing these activities. The information was gathered using milk recording sheets, which were administered in February (early lactation) and June (late lactation) in 2009. Milk consumption per household was similar among the three districts (P>0.05). Milk was utilised as both fresh and sour. Fresh milk was utilised with tea/coffee and porridge. Excess fresh milk was utilised to feed pets (mostly cats and puppies). The puppies were fed on mostly whey, and, at times, on fresh milk. Sour milk was utilised to prepare of umvubo (a mixture of sour milk and scrambled porridge (umphokoqo) or a mixture of sour milk and bread). In some cases, excess milk was given to neighbours as a form of social investment and fame. The quality of milk from Nguni and crossbred cows was compared in the fourth trial. Milk samples were evaluated for quality in early (February), mid (April) and late (June) lactation in 2009. The essential amino acids, non-essential amino acids and fatty acids were determined. Nguni milk had higher amino acids and fatty acids concentration than crossbreds (P<0.05). Nguni milk had higher arginine levels in the early and mid lactation periods compared to crossbred cows (P<0.05). Nguni milk had higher methionine and threonine levels than crossbred cows (P<0.05). Methionine levels in Nguni were 0.15, 0.19 and 0.18 in early, mid and late lactation while crossbred had 0.05, 0.05 and 0.06 (g/100ml), respectively. There were significant interactions between lactation stage and genotype for lysine levels with Nguni milk having higher (P<0.05) lysine levels in the mid and late lactation periods. Nguni cows had higher tyrosine, glycine and proline levels than crossbred cows (P<0.05). In the early lactation, Nguni cows had higher serine levels than crossbred cows (P<0.05). In mid lactation crossbred cows had higher serine levels than Nguni cows (P<0.05). There were significant differences between genotypes on fatty acid composition. Nguni milk had higher C12:0 levels than crossbreds (P<0.05). However, milk from crossbred cows had higher C14:0 levels than that for Nguni cows (P<0.05) and also had higher levels of C16:0 and C18:0 fatty acids compared to Nguni cows. Crossbred milk had higher levels of C18n1n9t in early lactation period than Nguni and decreased as the stage of lactation progressed (P<0.05). In the early lactation, the levels of C18n1nC in Nguni milk were higher (P<0.05) than in late lactation. In the mid and late lactation, crossbred cows milk had higher C18n1nC levels than in early lactation (P<0.05). Lactation stage and genotype affected saturated fatty, monounsaturated fatty acids, cis-fatty acids and omega 3 (n-3) to omega 6 (n-6). In general, Nguni milk had higher mineral composition than crossbred milk (P<0.05). In conclusion, Nguni calves performed better than crossbred calves under communal rangelands. There is a need for crossing Nguni cows with dairy breeds in commercial dairying by smalhoder farmers as a strategy for improving both milk quality and quantity.
- Full Text:
- Date Issued: 2009
Mobile monitors: protecting the will of the people
- Authors: Dugmore, Harry
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159377 , vital:40292 , https://hdl.handle.net/10520/EJC139912
- Description: The use of mobile phone technology in recent African elections has empowered citizens, allowing them to put in place the checks and balances needed to make elections freer and fairer in Africa - and elsewhere in the world, writes Harry Dugmore.
- Full Text:
- Date Issued: 2009
- Authors: Dugmore, Harry
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/159377 , vital:40292 , https://hdl.handle.net/10520/EJC139912
- Description: The use of mobile phone technology in recent African elections has empowered citizens, allowing them to put in place the checks and balances needed to make elections freer and fairer in Africa - and elsewhere in the world, writes Harry Dugmore.
- 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
Modelling of size-based portfolios using a mixture of normal distributions
- Authors: Janse Van Rensburg, Stéfan
- Date: 2009
- Subjects: Capital assets pricing model
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:10569 , http://hdl.handle.net/10948/985 , Capital assets pricing model
- Description: From option pricing using the Black and Scholes model, to determining the signi cance of regression coe cients in a capital asset pricing model (CAPM), the assumption of normality was pervasive throughout the eld of nance. This was despite evidence that nancial returns were non-normal, skewed and heavy- tailed. In addition to non-normality, there remained questions about the e ect of rm size on returns. Studies examining these di erences were limited to ex- amining the mean return, with respect to an asset pricing model, and did not consider higher moments. Janse van Rensburg, Sharp and Friskin (in press) attempted to address both the problem of non-normality and size simultaneously. They (Janse van Rens- burg et al in press) tted a mixture of two normal distributions, with common mean but di erent variances, to a small capitalisation portfolio and a large cap- italisation portfolio. Comparison of the mixture distributions yielded valuable insight into the di erences between the small and large capitalisation portfolios' risk. Janse van Rensburg et al (in press), however, identi ed several shortcom- ings within their work. These included data problems, such as survivorship bias and the exclusion of dividends, and the questionable use of standard statistical tests in the presence of non-normality. This study sought to correct the problems noted in the paper by Janse van Rensburg et al (in press) and to expand upon their research. To this end survivorship bias was eliminated and an e ective dividend was included into the return calculations. Weekly data were used, rather than the monthly data of Janse van Rensburg et al (in press). More portfolios, over shorter holding periods, were considered. This allowed the authors to test whether Janse van Rensburg et al's (in press) ndings remained valid under conditions di erent to their original study. Inference was also based on bootstrapped statistics, in order to circumvent problems associated with non-normality. Additionally, several di erent speci cations of the normal mixture distribution were considered, as opposed to only the two-component scale mixture. In the following, Chapter 2 provided a literature review of previous studies on return distributions and size e ects. The data, data preparation and portfolio formation were discussed in Chapter 3. Chapter 4 gave an overview of the statistical methods and tests used throughout the study. The empirical results of these tests, prior to risk adjustment, were presented in Chapter 5. The impact of risk adjustment on the distribution of returns was documented in Chapter 6. The study ended, Chapter 7, with a summary of the results and suggestions for future research.
- Full Text:
- Date Issued: 2009
- Authors: Janse Van Rensburg, Stéfan
- Date: 2009
- Subjects: Capital assets pricing model
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:10569 , http://hdl.handle.net/10948/985 , Capital assets pricing model
- Description: From option pricing using the Black and Scholes model, to determining the signi cance of regression coe cients in a capital asset pricing model (CAPM), the assumption of normality was pervasive throughout the eld of nance. This was despite evidence that nancial returns were non-normal, skewed and heavy- tailed. In addition to non-normality, there remained questions about the e ect of rm size on returns. Studies examining these di erences were limited to ex- amining the mean return, with respect to an asset pricing model, and did not consider higher moments. Janse van Rensburg, Sharp and Friskin (in press) attempted to address both the problem of non-normality and size simultaneously. They (Janse van Rens- burg et al in press) tted a mixture of two normal distributions, with common mean but di erent variances, to a small capitalisation portfolio and a large cap- italisation portfolio. Comparison of the mixture distributions yielded valuable insight into the di erences between the small and large capitalisation portfolios' risk. Janse van Rensburg et al (in press), however, identi ed several shortcom- ings within their work. These included data problems, such as survivorship bias and the exclusion of dividends, and the questionable use of standard statistical tests in the presence of non-normality. This study sought to correct the problems noted in the paper by Janse van Rensburg et al (in press) and to expand upon their research. To this end survivorship bias was eliminated and an e ective dividend was included into the return calculations. Weekly data were used, rather than the monthly data of Janse van Rensburg et al (in press). More portfolios, over shorter holding periods, were considered. This allowed the authors to test whether Janse van Rensburg et al's (in press) ndings remained valid under conditions di erent to their original study. Inference was also based on bootstrapped statistics, in order to circumvent problems associated with non-normality. Additionally, several di erent speci cations of the normal mixture distribution were considered, as opposed to only the two-component scale mixture. In the following, Chapter 2 provided a literature review of previous studies on return distributions and size e ects. The data, data preparation and portfolio formation were discussed in Chapter 3. Chapter 4 gave an overview of the statistical methods and tests used throughout the study. The empirical results of these tests, prior to risk adjustment, were presented in Chapter 5. The impact of risk adjustment on the distribution of returns was documented in Chapter 6. The study ended, Chapter 7, with a summary of the results and suggestions for future research.
- Full Text:
- Date Issued: 2009
Models of development for blowfly sister species Chrysomya chloropyga and Chrysomya putoria
- Richards, Cameron S, Crous, Kendall L, Villet, Martin H
- Authors: Richards, Cameron S , Crous, Kendall L , Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:73967 , https://doi.org/10.1111/j.1365-2915.2008.00767.x
- Description: Developmental curves for the sister species Chrysomya chloropyga (Wiedemann, 1818) and Chrysomya putoria (Wiedemann, 1830) (Diptera: Calliphoridae) were established at eight and 10 different constant temperatures, respectively, using developmental landmarks and body length as measures of age. The thermal summation constants (K) and developmental threshold (D0) were calculated for five developmental landmarks using a previously described method. Isomorphen and isomegalen diagrams were also constructed for the purpose of estimating postmortem intervals (PMIs). Chrysomya chloropyga had an average developmental threshold value (D0) of 10.91 °C (standard error [SE] = 0.94 °C, n = 5), significantly lower than that of C. putoria (13.42 °C, SE = 0.45 °C, n = 5) (paired t‐test: t = − 4.63, d.f. = 8, P 0.00). Similarly, K values for C. chloropyga were larger than those for C. putoria for all developmental events except onset of the wandering phase. These are the first data that can be used to calculate minimum PMIs and predict population growth of C. chloropyga and C. putoria in Africa; the data indicate that developmental data for one of these species cannot be used as surrogate data for the sister species.
- Full Text:
- Date Issued: 2009
- Authors: Richards, Cameron S , Crous, Kendall L , Villet, Martin H
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/${Handle} , vital:73967 , https://doi.org/10.1111/j.1365-2915.2008.00767.x
- Description: Developmental curves for the sister species Chrysomya chloropyga (Wiedemann, 1818) and Chrysomya putoria (Wiedemann, 1830) (Diptera: Calliphoridae) were established at eight and 10 different constant temperatures, respectively, using developmental landmarks and body length as measures of age. The thermal summation constants (K) and developmental threshold (D0) were calculated for five developmental landmarks using a previously described method. Isomorphen and isomegalen diagrams were also constructed for the purpose of estimating postmortem intervals (PMIs). Chrysomya chloropyga had an average developmental threshold value (D0) of 10.91 °C (standard error [SE] = 0.94 °C, n = 5), significantly lower than that of C. putoria (13.42 °C, SE = 0.45 °C, n = 5) (paired t‐test: t = − 4.63, d.f. = 8, P 0.00). Similarly, K values for C. chloropyga were larger than those for C. putoria for all developmental events except onset of the wandering phase. These are the first data that can be used to calculate minimum PMIs and predict population growth of C. chloropyga and C. putoria in Africa; the data indicate that developmental data for one of these species cannot be used as surrogate data for the sister species.
- Full Text:
- Date Issued: 2009
Molecular and biochemical analysis of the diet of the black rhinoceros
- Authors: Kgopa, Ananias Hodi
- Date: 2009 , 2013-07-15
- Subjects: Black rhinoceros -- South Africa -- Eastern Cape , Browse (Animal food) -- South Africa -- Eastern Cape -- Analysis , Black rhinoceros -- Manure -- Analysis , Phenols , Antioxidants , Plant ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4064 , http://hdl.handle.net/10962/d1004721 , Black rhinoceros -- South Africa -- Eastern Cape , Browse (Animal food) -- South Africa -- Eastern Cape -- Analysis , Black rhinoceros -- Manure -- Analysis , Phenols , Antioxidants , Plant ecology -- South Africa -- Eastern Cape
- Description: The black rhinoceros, Diceros bicornis, is listed as critically endangered. The black rhinoceros population in the Great Fish River Reserve (GFRR) has increased steadily to a current estimate of one hundred animals since the re-introduction of four animals in 1986. In an effort to contribute to the effective conservation and management of this species, dietary composition was studied in the medium Portulcaria thicket vegetation of the GFRR. This study used a molecular approach to determine the diet of the black rhinoceros of the GFRR by sequencing the ribulose bisphosphate carboxylase large subunit (rbcL) gene in plants and dung. Twenty-three plant species were collected from the reserve, and 802 bp of the rbcL gene were sequenced. These plant sequences were used as a reference database for the identification of plant sequences generated from black rhinoceros dung. Initial studies investigated the amplification, cloning and sequencing of DNA extracted from the dung samples which indicated the viability of the molecular approach. Thereafter, dung generated rbcL DNA was analyzed by GS FLX sequencing. Of the plant sequences identified by comparison to the GenBank database, Carissa bispinosa was the most prevalent. The study further characterized the antioxidant activities and phenolic content of plants eaten by the black rhinoceros using four different assays. Phyllanthus verrucosus, Putterlickia pyracantha, Maytenus capitata, Euclea undulata and Ozoroa mucrunata consistently had high antioxidant activities when assayed against 2,2-azinobis (3-ethyl benzothiazolium-6-sulfonic acid) (ABTSʹ⁺), 2,2-diphenyl-1-picrylhydrazyl (DPPHʹ), and ferric reducing antioxidant potentials (FRAP) and phenolic content when evaluated using the Folin-Ciocalteu assay. The majority of plants investigated showed low antioxidant potentials and low phenolic content. The extent to which antioxidants influenced the browse selection by the black rhinoceros remains inconclusive.
- Full Text:
- Date Issued: 2009
- Authors: Kgopa, Ananias Hodi
- Date: 2009 , 2013-07-15
- Subjects: Black rhinoceros -- South Africa -- Eastern Cape , Browse (Animal food) -- South Africa -- Eastern Cape -- Analysis , Black rhinoceros -- Manure -- Analysis , Phenols , Antioxidants , Plant ecology -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4064 , http://hdl.handle.net/10962/d1004721 , Black rhinoceros -- South Africa -- Eastern Cape , Browse (Animal food) -- South Africa -- Eastern Cape -- Analysis , Black rhinoceros -- Manure -- Analysis , Phenols , Antioxidants , Plant ecology -- South Africa -- Eastern Cape
- Description: The black rhinoceros, Diceros bicornis, is listed as critically endangered. The black rhinoceros population in the Great Fish River Reserve (GFRR) has increased steadily to a current estimate of one hundred animals since the re-introduction of four animals in 1986. In an effort to contribute to the effective conservation and management of this species, dietary composition was studied in the medium Portulcaria thicket vegetation of the GFRR. This study used a molecular approach to determine the diet of the black rhinoceros of the GFRR by sequencing the ribulose bisphosphate carboxylase large subunit (rbcL) gene in plants and dung. Twenty-three plant species were collected from the reserve, and 802 bp of the rbcL gene were sequenced. These plant sequences were used as a reference database for the identification of plant sequences generated from black rhinoceros dung. Initial studies investigated the amplification, cloning and sequencing of DNA extracted from the dung samples which indicated the viability of the molecular approach. Thereafter, dung generated rbcL DNA was analyzed by GS FLX sequencing. Of the plant sequences identified by comparison to the GenBank database, Carissa bispinosa was the most prevalent. The study further characterized the antioxidant activities and phenolic content of plants eaten by the black rhinoceros using four different assays. Phyllanthus verrucosus, Putterlickia pyracantha, Maytenus capitata, Euclea undulata and Ozoroa mucrunata consistently had high antioxidant activities when assayed against 2,2-azinobis (3-ethyl benzothiazolium-6-sulfonic acid) (ABTSʹ⁺), 2,2-diphenyl-1-picrylhydrazyl (DPPHʹ), and ferric reducing antioxidant potentials (FRAP) and phenolic content when evaluated using the Folin-Ciocalteu assay. The majority of plants investigated showed low antioxidant potentials and low phenolic content. The extent to which antioxidants influenced the browse selection by the black rhinoceros remains inconclusive.
- Full Text:
- Date Issued: 2009
Monetary policy, inflation, unemployment and the Phillips curve in South Africa
- Authors: Chicheke, Aaron
- Date: 2009
- Subjects: Monetary policy , Inflation (Finance) , Economic policy -- Mathematical models , Unemployment -- South Africa , Phillips curve
- Language: English
- Type: Thesis , Masters , M Com
- Identifier: vital:11453 , http://hdl.handle.net/10353/d1001202 , Monetary policy , Inflation (Finance) , Economic policy -- Mathematical models , Unemployment -- South Africa , Phillips curve
- Description: Inflation and unemployment are perhaps the two most important challenges that face the South African economy of today. Firstly, the study examines the relationship between monetary policy and the two economic fundamentals (inflation and unemployment), using the VEC modeling technique. The model regresses the monetary policy variable against inflation and unemployment growth over the period 1980-2008. The results suggest that (1) there is a long run relationship between inflation and unemployment (2) monetary policy reacts more to variations in inflation compared to variations in unemployment. Secondly, the relationship between inflation and unemployment as explained by the Phillips curve is investigated. The results show that there is a positive relationship between inflation and unemployment.
- Full Text:
- Date Issued: 2009
- Authors: Chicheke, Aaron
- Date: 2009
- Subjects: Monetary policy , Inflation (Finance) , Economic policy -- Mathematical models , Unemployment -- South Africa , Phillips curve
- Language: English
- Type: Thesis , Masters , M Com
- Identifier: vital:11453 , http://hdl.handle.net/10353/d1001202 , Monetary policy , Inflation (Finance) , Economic policy -- Mathematical models , Unemployment -- South Africa , Phillips curve
- Description: Inflation and unemployment are perhaps the two most important challenges that face the South African economy of today. Firstly, the study examines the relationship between monetary policy and the two economic fundamentals (inflation and unemployment), using the VEC modeling technique. The model regresses the monetary policy variable against inflation and unemployment growth over the period 1980-2008. The results suggest that (1) there is a long run relationship between inflation and unemployment (2) monetary policy reacts more to variations in inflation compared to variations in unemployment. Secondly, the relationship between inflation and unemployment as explained by the Phillips curve is investigated. The results show that there is a positive relationship between inflation and unemployment.
- Full Text:
- Date Issued: 2009
Movement bahaviour of three South African inshore sparid species in rocky intertidal and shallow subtidal habitats
- Authors: Watt-Pringle, Peter Andrew
- Date: 2009
- Subjects: Sparidae -- South Africa , Diplodus , Sparodon Durbanensis , Fisheries -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5302 , http://hdl.handle.net/10962/d1005147 , Sparidae -- South Africa , Diplodus , Sparodon Durbanensis , Fisheries -- South Africa
- Description: This study investigated the movement behaviour of three inshore South African sparids – blacktail (Diplodus sargus capensis), zebra (Diplodus cervinus hottentotus) and white musselcracker (Sparodon durbanensis), popular inshore fishery species caught in appreciable numbers along much of the South African coast. The first study component examined movements of juveniles in a rocky intertidal nursery area at Schoenmakerskop near Port Elizabeth. Juveniles in a single gully were tagged with Visible Implant Elastomer (VIE) and resighted at the study site on snorkelling gear over a seven-month period. Tagged zebra and musselcracker displayed limited movement between potential low tide refuges, being observed repeatedly in the same gully over the full duration of the study. However, blacktail displayed greater movements and were seen infrequently in the later period of the study, probably having undergone an ontogenetic habitat shift to subtidal areas. There was evidence that blacktail maintain use of their intertidal nursery over high tide, during which the other two species moved into shallower areas adjacent to their low tide refuge. The results of three national tagging programs were analysed to determine the movement patterns of adolescent and adult fishes. The coast-wide ORI-WWF National Voluntary Tagging Program and two dedicated research programs in marine protected areas (MPAs) at De Hoop MPA and Tsitsikamma National Park (TNP) recorded few large-scale movements of tagged adult blacktail, zebra and juvenile musselcracker. High spatial-resolution data from the TNP suggested movements were usually on scales far smaller than one km. Together with long periods at liberty for many recaptured individuals, this suggests these fishes are longterm residents of small home range areas. However, tagged musselcracker over 600 mm forklength (adults) were observed to make large-scale movements, including some in excess of 800 km from Eastern Cape to KwaZulu-Natal waters. Predominantly eastward movements of adults recaptured during the spawning season indicate seasonal spawning migrations that occur in different regions of the coast. These enable the use of prevailing oceanographic currents to disperse eggs and larvae to suitable rocky nursery habitat. The third component of this study made use of high-resolution data on the temporal and spatial distribution of catches by scientific angling in the TNP to examine the daily activity patterns of the study species in relation to diel and tidal cycles, and habitat use. Blacktail capture probability was correlated with the diurnal light cycle, with peaks close to twilight suggesting elevated crepuscular foraging activity. Catches of blacktail, zebra and small musselcracker were correlated with the tidal cycle, foraging peaking over high tide periods. All three species used shallow inshore habitats extensively for foraging, blacktail showing a preference for sandy areas, while zebra and small musselcracker preferred shallow reef. Capture probability of larger musselcracker, however, was unrelated to habitat, possibly evidence of increasing area and habitat use with an ontogenetic change in diet. The lifetime movement patterns of these three species are discussed in relation to conservation measures and their management in South African fisheries. Restricted movement throughout post-settlement life for blacktail and zebra, and during the juvenile phase for musselcracker, makes local populations vulnerable to overexploitation. At present, MPAs probably play an important role in protecting local blacktail and zebra populations from overexploitation, and limited post-settlement movements mean the degree of larval dispersal between protected and adjacent areas will likely determine the effectiveness of MPAs in enhancing fisheries for these species. By contrast, MPAs likely provide recruits to fisheries for musselcracker during ontogenetic movements and dispersal from MPAs during spawning migrations. MPAs only offer partial protection to adult musselcracker populations in the spawning season, but this could nevertheless be significant under high levels of exploitation.
- Full Text:
- Date Issued: 2009
- Authors: Watt-Pringle, Peter Andrew
- Date: 2009
- Subjects: Sparidae -- South Africa , Diplodus , Sparodon Durbanensis , Fisheries -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5302 , http://hdl.handle.net/10962/d1005147 , Sparidae -- South Africa , Diplodus , Sparodon Durbanensis , Fisheries -- South Africa
- Description: This study investigated the movement behaviour of three inshore South African sparids – blacktail (Diplodus sargus capensis), zebra (Diplodus cervinus hottentotus) and white musselcracker (Sparodon durbanensis), popular inshore fishery species caught in appreciable numbers along much of the South African coast. The first study component examined movements of juveniles in a rocky intertidal nursery area at Schoenmakerskop near Port Elizabeth. Juveniles in a single gully were tagged with Visible Implant Elastomer (VIE) and resighted at the study site on snorkelling gear over a seven-month period. Tagged zebra and musselcracker displayed limited movement between potential low tide refuges, being observed repeatedly in the same gully over the full duration of the study. However, blacktail displayed greater movements and were seen infrequently in the later period of the study, probably having undergone an ontogenetic habitat shift to subtidal areas. There was evidence that blacktail maintain use of their intertidal nursery over high tide, during which the other two species moved into shallower areas adjacent to their low tide refuge. The results of three national tagging programs were analysed to determine the movement patterns of adolescent and adult fishes. The coast-wide ORI-WWF National Voluntary Tagging Program and two dedicated research programs in marine protected areas (MPAs) at De Hoop MPA and Tsitsikamma National Park (TNP) recorded few large-scale movements of tagged adult blacktail, zebra and juvenile musselcracker. High spatial-resolution data from the TNP suggested movements were usually on scales far smaller than one km. Together with long periods at liberty for many recaptured individuals, this suggests these fishes are longterm residents of small home range areas. However, tagged musselcracker over 600 mm forklength (adults) were observed to make large-scale movements, including some in excess of 800 km from Eastern Cape to KwaZulu-Natal waters. Predominantly eastward movements of adults recaptured during the spawning season indicate seasonal spawning migrations that occur in different regions of the coast. These enable the use of prevailing oceanographic currents to disperse eggs and larvae to suitable rocky nursery habitat. The third component of this study made use of high-resolution data on the temporal and spatial distribution of catches by scientific angling in the TNP to examine the daily activity patterns of the study species in relation to diel and tidal cycles, and habitat use. Blacktail capture probability was correlated with the diurnal light cycle, with peaks close to twilight suggesting elevated crepuscular foraging activity. Catches of blacktail, zebra and small musselcracker were correlated with the tidal cycle, foraging peaking over high tide periods. All three species used shallow inshore habitats extensively for foraging, blacktail showing a preference for sandy areas, while zebra and small musselcracker preferred shallow reef. Capture probability of larger musselcracker, however, was unrelated to habitat, possibly evidence of increasing area and habitat use with an ontogenetic change in diet. The lifetime movement patterns of these three species are discussed in relation to conservation measures and their management in South African fisheries. Restricted movement throughout post-settlement life for blacktail and zebra, and during the juvenile phase for musselcracker, makes local populations vulnerable to overexploitation. At present, MPAs probably play an important role in protecting local blacktail and zebra populations from overexploitation, and limited post-settlement movements mean the degree of larval dispersal between protected and adjacent areas will likely determine the effectiveness of MPAs in enhancing fisheries for these species. By contrast, MPAs likely provide recruits to fisheries for musselcracker during ontogenetic movements and dispersal from MPAs during spawning migrations. MPAs only offer partial protection to adult musselcracker populations in the spawning season, but this could nevertheless be significant under high levels of exploitation.
- Full Text:
- Date Issued: 2009
Mulch tower treatment system for greywater reuse Part II: destructive testing and effluent treatment
- Tandlich, Roman, Zuma, Bongumusa M, Whittington-Jones, Kevin J, Burgess, Jo E
- Authors: Tandlich, Roman , Zuma, Bongumusa M , Whittington-Jones, Kevin J , Burgess, Jo E
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71547 , vital:29863 , https://doi.org/10.1016/j.desal.2008.03.031
- Description: The mulch tower (MT) system described in Part I was tested to failure to determine its range of operating conditions. An increase in the influent temperature led to a statistically significant release of components of the chemical oxygen demand (COD) and the five day biochemical oxygen demand (BOD5), as well as phosphates from the MT system. Heterotrophic plate count (HPC) of the mulch layer dropped from 1.2 (± 0.6) × 106/g dry weight to 1.5 (± 0.3) × 105/g dry weight of the mulch layer with increases of the influent temperature. This indicates that the increase in influent temperature killed off some of the active biomass in the MT biofilm. After a five day drying period under active aeration, the MT system retained the ability to remove COD, total suspended solids (TSS), and nitrates. Greywater treatment by the MT system became impossible after a 48 day drying period under active aeration. Chlorination of the simulated MT effluent with a mixture of sodium dichloroisocyanurate and trichloroisocyanuric acid decreased the faecal coliform concentrations (FC) and the total coliform concentrations (TC) below 800 CFUs/100 ml within 65 h. Beyond 65 h, the pH of the effluent became highly acidic. To maintain optimum performance influent should be fed into the MT system at least once every 5 days, sufficient aeration should be guaranteed, and the MT effluent should be chlorinated for 65 h to eliminate all pathogens before any reuse.
- Full Text: false
- Date Issued: 2009
Mulch tower treatment system for greywater reuse Part II: destructive testing and effluent treatment
- Authors: Tandlich, Roman , Zuma, Bongumusa M , Whittington-Jones, Kevin J , Burgess, Jo E
- Date: 2009
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/71547 , vital:29863 , https://doi.org/10.1016/j.desal.2008.03.031
- Description: The mulch tower (MT) system described in Part I was tested to failure to determine its range of operating conditions. An increase in the influent temperature led to a statistically significant release of components of the chemical oxygen demand (COD) and the five day biochemical oxygen demand (BOD5), as well as phosphates from the MT system. Heterotrophic plate count (HPC) of the mulch layer dropped from 1.2 (± 0.6) × 106/g dry weight to 1.5 (± 0.3) × 105/g dry weight of the mulch layer with increases of the influent temperature. This indicates that the increase in influent temperature killed off some of the active biomass in the MT biofilm. After a five day drying period under active aeration, the MT system retained the ability to remove COD, total suspended solids (TSS), and nitrates. Greywater treatment by the MT system became impossible after a 48 day drying period under active aeration. Chlorination of the simulated MT effluent with a mixture of sodium dichloroisocyanurate and trichloroisocyanuric acid decreased the faecal coliform concentrations (FC) and the total coliform concentrations (TC) below 800 CFUs/100 ml within 65 h. Beyond 65 h, the pH of the effluent became highly acidic. To maintain optimum performance influent should be fed into the MT system at least once every 5 days, sufficient aeration should be guaranteed, and the MT effluent should be chlorinated for 65 h to eliminate all pathogens before any reuse.
- Full Text: false
- Date Issued: 2009