Hydrothermal co-liquefaction of microalgae biomass and coal
- Authors: Charlie, David
- Date: 2015
- Subjects: Microalgae -- Biotechnology Biomass chemicals , Biomass energy
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/50087 , vital:42035
- Description: In this research, the objective was to investigate under the chosen liquefaction conditions whether co-liquefaction of coal and microalgae biomass as agglomerates does possess a distinct advantage over the individual liquefaction of microalgae and coal. This was initially done by preparing dry micro algal biomass, followed by the preparation of coal fines and finally coal-algae as agglomerates. The agglomerates were prepared by continuously adsorbing wet concentrated microalgae slurry/solution onto the dry coal fines in order to prepare different ratios of coal-algae agglomerate(s). Ultimate analysis of the starting material (coal fines and the microalgae) as well the agglomerates then followed. According to research, wet microalgae biomass has the potential of acting as a hydrogen donor. By preparing the agglomerates, the rationale was to promote hydrogen supply from the micro algal biomass that has high hydrogen content to the coal with lower hydrogen content. The resulting product was then expected to have fairly higher hydrogen content. However, this was not observed or evident from the elemental analysis results. The results (elemental composition) showed no difference between the agglomerates and the coal. Based on the observed ultimate analysis results, liquefaction experiments were conducted to determine whether hydrogen transfer and the expected synergistic effect between micro algal biomass and coal would occur. The crude oil product was recovered and simulated distillation technique was used for the characterization of the crude oil product. The results we in agreement that higher yields can be achieved during co-liquefaction as compared to the individual liquefaction. A possible synergistic effect that was investigated in this research existed. Liquefaction results provided evidence of higher yields recovery from the agglomerates compared to those of coal fines and microalgae biomass. Although there was higher recovery on the agglomerates, there appears to be a downward trend (decrease) in product recovery with higher loadings of micro algal biomass on to the coal. This means that higher loading of micro algal biomass tend to suppress liquefaction of coal, thus resulting in lower product recovery. While lower loadings tend to effectively facilitate the liquefaction of coal, thus proving that the proposed synergistic effect between the two does exist. Overall product recovery (yields) of the agglomerates is higher compared to the individual recovery of coal fines and microalgae biomass. This was followed by mass balancing to determine the overall conversion. Higher conversions were achieved on the agglomerates compared to coal. This could mean that microalgae have the potential to facilitate the liquefaction of coal and improve its conversion. The observed trend results in improved conversion as well as higher oil yields (simulated distillation results). Overall, the mass balancing provided insightful information regarding the coal-microalgae interaction based on the conversion, and this further corresponds or supports the simulated distillation results. This research paper provides evidence of the synergistic effect that exists between micro algal biomass and coal.
- Full Text:
- Date Issued: 2015
- Authors: Charlie, David
- Date: 2015
- Subjects: Microalgae -- Biotechnology Biomass chemicals , Biomass energy
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/50087 , vital:42035
- Description: In this research, the objective was to investigate under the chosen liquefaction conditions whether co-liquefaction of coal and microalgae biomass as agglomerates does possess a distinct advantage over the individual liquefaction of microalgae and coal. This was initially done by preparing dry micro algal biomass, followed by the preparation of coal fines and finally coal-algae as agglomerates. The agglomerates were prepared by continuously adsorbing wet concentrated microalgae slurry/solution onto the dry coal fines in order to prepare different ratios of coal-algae agglomerate(s). Ultimate analysis of the starting material (coal fines and the microalgae) as well the agglomerates then followed. According to research, wet microalgae biomass has the potential of acting as a hydrogen donor. By preparing the agglomerates, the rationale was to promote hydrogen supply from the micro algal biomass that has high hydrogen content to the coal with lower hydrogen content. The resulting product was then expected to have fairly higher hydrogen content. However, this was not observed or evident from the elemental analysis results. The results (elemental composition) showed no difference between the agglomerates and the coal. Based on the observed ultimate analysis results, liquefaction experiments were conducted to determine whether hydrogen transfer and the expected synergistic effect between micro algal biomass and coal would occur. The crude oil product was recovered and simulated distillation technique was used for the characterization of the crude oil product. The results we in agreement that higher yields can be achieved during co-liquefaction as compared to the individual liquefaction. A possible synergistic effect that was investigated in this research existed. Liquefaction results provided evidence of higher yields recovery from the agglomerates compared to those of coal fines and microalgae biomass. Although there was higher recovery on the agglomerates, there appears to be a downward trend (decrease) in product recovery with higher loadings of micro algal biomass on to the coal. This means that higher loading of micro algal biomass tend to suppress liquefaction of coal, thus resulting in lower product recovery. While lower loadings tend to effectively facilitate the liquefaction of coal, thus proving that the proposed synergistic effect between the two does exist. Overall product recovery (yields) of the agglomerates is higher compared to the individual recovery of coal fines and microalgae biomass. This was followed by mass balancing to determine the overall conversion. Higher conversions were achieved on the agglomerates compared to coal. This could mean that microalgae have the potential to facilitate the liquefaction of coal and improve its conversion. The observed trend results in improved conversion as well as higher oil yields (simulated distillation results). Overall, the mass balancing provided insightful information regarding the coal-microalgae interaction based on the conversion, and this further corresponds or supports the simulated distillation results. This research paper provides evidence of the synergistic effect that exists between micro algal biomass and coal.
- Full Text:
- Date Issued: 2015
A framework for secure mobility in wireless overlay networks
- Authors: Chen, Hejun
- Date: 2006
- Subjects: Wireless communication systems , Computer networks
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9778 , http://hdl.handle.net/10948/819 , Wireless communication systems , Computer networks
- Description: Various wireless networks are widely deployed world wide. Current technologies employed in these networks vary widely in terms of bandwidths, latencies, frequencies, and media access methods. Most existing wireless network technologies can be divided into two categories: those that provide a low-bandwidth service over a wide geographic area, for example UMTS, and those that provide a high bandwidth service over a narrow geographic area, for example 802.11. Although it would be desirable to provide a high- bandwidth service over a wide coverage region to mobile users all the time, no single wireless network technology simultaneously satisfies these require- ments. Wireless Overlay Networks, a hierarchical structure of wireless personal area, local area, and wide area data networks, is considered as an efficient and scalable way to solve this problem. Due to the wide deployment of UMTS and 802.11 WLAN, this study attempts to combine them to implement the concept of Wireless Overlay Net- works. Furthermore, the information transmitted over this Wireless Overlay Networks is protected in terms of authentication, integrity and confidentiality. To achieve this goal, this study aims to combine GPRS, Mobile IP and IPSec to propose a framework for secure mobility in Wireless Overlay Networks. The framework is developed in three steps: Firstly, this study addresses the problem of combining GPRS and Mo- bile IP, so that GPRS users are provided with Mobile IP service. This results in presenting a uniform Mobile IP interface to peers regardless of whether mobile users use UMTS or 802.11 WLAN. Secondly, this study discovers the existing problem when combining Mobile IP and IPSec, and proposes a Dual Home Agent Architecture to achieve secure mobility. Finally, based on the output of the previous two steps, a complete framework is proposed, which achieves secure mobility in Wireless Overlay Networks, specifically, in UMTS and 802.11 WLAN. The framework also implements seamless handover when mobile users switch between UMTS and 802.11. This results in UMTS and 802.11 WLAN looking like a single network when participating in this framework, and presents seamless and secure mobility.
- Full Text:
- Date Issued: 2006
- Authors: Chen, Hejun
- Date: 2006
- Subjects: Wireless communication systems , Computer networks
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9778 , http://hdl.handle.net/10948/819 , Wireless communication systems , Computer networks
- Description: Various wireless networks are widely deployed world wide. Current technologies employed in these networks vary widely in terms of bandwidths, latencies, frequencies, and media access methods. Most existing wireless network technologies can be divided into two categories: those that provide a low-bandwidth service over a wide geographic area, for example UMTS, and those that provide a high bandwidth service over a narrow geographic area, for example 802.11. Although it would be desirable to provide a high- bandwidth service over a wide coverage region to mobile users all the time, no single wireless network technology simultaneously satisfies these require- ments. Wireless Overlay Networks, a hierarchical structure of wireless personal area, local area, and wide area data networks, is considered as an efficient and scalable way to solve this problem. Due to the wide deployment of UMTS and 802.11 WLAN, this study attempts to combine them to implement the concept of Wireless Overlay Net- works. Furthermore, the information transmitted over this Wireless Overlay Networks is protected in terms of authentication, integrity and confidentiality. To achieve this goal, this study aims to combine GPRS, Mobile IP and IPSec to propose a framework for secure mobility in Wireless Overlay Networks. The framework is developed in three steps: Firstly, this study addresses the problem of combining GPRS and Mo- bile IP, so that GPRS users are provided with Mobile IP service. This results in presenting a uniform Mobile IP interface to peers regardless of whether mobile users use UMTS or 802.11 WLAN. Secondly, this study discovers the existing problem when combining Mobile IP and IPSec, and proposes a Dual Home Agent Architecture to achieve secure mobility. Finally, based on the output of the previous two steps, a complete framework is proposed, which achieves secure mobility in Wireless Overlay Networks, specifically, in UMTS and 802.11 WLAN. The framework also implements seamless handover when mobile users switch between UMTS and 802.11. This results in UMTS and 802.11 WLAN looking like a single network when participating in this framework, and presents seamless and secure mobility.
- Full Text:
- Date Issued: 2006
Factors that impact on the user experience of a mobile school health application
- Authors: Chetty, Avineshin
- Date: 2018
- Subjects: Wireless communication systems in medical care , Medical informatics Application software Technology -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/21801 , vital:29780
- Description: In South Africa, the National Department of Health through its Integrated School Health Policy, use school nurses, to visit schools and perform health screening of learners which focus mainly on nutrition, eyesight and hearing. To date, this was done manually, but with the advance of technology, there is a need to investigate the use of for example, mobile applications to assist with health screening tasks. As part of the TECH4RED project in the Chris Hani district, a mobile school health assessment application was implemented and used over a period three years. As this is a new way of conducting the health screening, there is a need to understand the user experiences of the end users who interact with both the technology and the application. The objective of this study was to investigate the perceived factors that impact on the UX of the school health assessment application. The research aimed to understand the uses, advantages and disadvantages of mobile health applications. It also aimed at determining whether there are unique characteristics of the targeted end users and if so, whether such characteristics would affect the overall UX when using the application. Determining the levels of satisfaction and investigating the apparent challenges the users faced while interacting with the application provided some insights into underlying factors. A theoretical framework was constructed using existing literature. Using a case study approach, data was collected by means of end user satisfaction and user experience questionnaires. Additional data collection was done by means of an expert review to obtain feedback on the content and workflow of the school health assessment application. The resulting findings from the research included, a descriptive list of factors that impact the school health assessment application, as well as a subsequent list of recommendations for improvements. These key-findings could lead to possible guidelines, while additionally, providing valuable insight into mobile school health applications on the whole.
- Full Text:
- Date Issued: 2018
- Authors: Chetty, Avineshin
- Date: 2018
- Subjects: Wireless communication systems in medical care , Medical informatics Application software Technology -- Psychological aspects
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/21801 , vital:29780
- Description: In South Africa, the National Department of Health through its Integrated School Health Policy, use school nurses, to visit schools and perform health screening of learners which focus mainly on nutrition, eyesight and hearing. To date, this was done manually, but with the advance of technology, there is a need to investigate the use of for example, mobile applications to assist with health screening tasks. As part of the TECH4RED project in the Chris Hani district, a mobile school health assessment application was implemented and used over a period three years. As this is a new way of conducting the health screening, there is a need to understand the user experiences of the end users who interact with both the technology and the application. The objective of this study was to investigate the perceived factors that impact on the UX of the school health assessment application. The research aimed to understand the uses, advantages and disadvantages of mobile health applications. It also aimed at determining whether there are unique characteristics of the targeted end users and if so, whether such characteristics would affect the overall UX when using the application. Determining the levels of satisfaction and investigating the apparent challenges the users faced while interacting with the application provided some insights into underlying factors. A theoretical framework was constructed using existing literature. Using a case study approach, data was collected by means of end user satisfaction and user experience questionnaires. Additional data collection was done by means of an expert review to obtain feedback on the content and workflow of the school health assessment application. The resulting findings from the research included, a descriptive list of factors that impact the school health assessment application, as well as a subsequent list of recommendations for improvements. These key-findings could lead to possible guidelines, while additionally, providing valuable insight into mobile school health applications on the whole.
- Full Text:
- Date Issued: 2018
Development of thick section friction stir welding using a sliding tool shoulder
- Authors: Chetty, Shamalin
- Date: 2013
- Subjects: Friction welding
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9633 , http://hdl.handle.net/10948/d1015081
- Description: Sliding shoulder friction stir welding (SSFSW) is an alternative joining technique to the conventional friction stir welding process. The welding mechanism comprises of a rotating probe and a non-rotating shoulder. The shoulder therefore does not contribute to any heat generation or plastic deformation. When welding thicker section material, the contribution of heat generation from the shoulder becomes less significant and most of the heat and plastic deformation must be generated by the tool probe. For this reason it was decided to develop the process for thick section AA6082-T6. Due to the stationary (non-rotating) shoulder the weld track is smooth and there is no reduction in cross-sectional area. This research is based on the development of a sliding shoulder friction stir welding tool with the ability to create joints of up to 25mm thick on aluminium alloy 6082-T6 plate as well as the associated process development. The sliding shoulder friction stir welding tool was designed, manufactured and tested by initially performing partial penetration welds with various size tool probes and then finally by performing a sliding shoulder friction stir butt weld on 25mm thick plate. As welds were performed and more knowledge gained about the process, design modifications were made. These included varying the clearance between the tool probe and stationary shoulder; the profile of the shoulder which contributes to material flow during the process; and supporting the tool probe to prevent deflection when welding thicker sections at high forge forces. From the sliding shoulder friction stir welds performed, an understanding of material flow during the process was gained when analysing the macro-sections and exit holes of the welds. Typical process forces and torques associated with the process were measured to assist with future head unit and tool designs with regard to sliding shoulder friction stir welding.
- Full Text:
- Date Issued: 2013
- Authors: Chetty, Shamalin
- Date: 2013
- Subjects: Friction welding
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9633 , http://hdl.handle.net/10948/d1015081
- Description: Sliding shoulder friction stir welding (SSFSW) is an alternative joining technique to the conventional friction stir welding process. The welding mechanism comprises of a rotating probe and a non-rotating shoulder. The shoulder therefore does not contribute to any heat generation or plastic deformation. When welding thicker section material, the contribution of heat generation from the shoulder becomes less significant and most of the heat and plastic deformation must be generated by the tool probe. For this reason it was decided to develop the process for thick section AA6082-T6. Due to the stationary (non-rotating) shoulder the weld track is smooth and there is no reduction in cross-sectional area. This research is based on the development of a sliding shoulder friction stir welding tool with the ability to create joints of up to 25mm thick on aluminium alloy 6082-T6 plate as well as the associated process development. The sliding shoulder friction stir welding tool was designed, manufactured and tested by initially performing partial penetration welds with various size tool probes and then finally by performing a sliding shoulder friction stir butt weld on 25mm thick plate. As welds were performed and more knowledge gained about the process, design modifications were made. These included varying the clearance between the tool probe and stationary shoulder; the profile of the shoulder which contributes to material flow during the process; and supporting the tool probe to prevent deflection when welding thicker sections at high forge forces. From the sliding shoulder friction stir welds performed, an understanding of material flow during the process was gained when analysing the macro-sections and exit holes of the welds. Typical process forces and torques associated with the process were measured to assist with future head unit and tool designs with regard to sliding shoulder friction stir welding.
- Full Text:
- Date Issued: 2013
The use of conceptual costume design to express the emotional trajectory of the play sounds of South End
- Authors: Chingosho, Vimbai
- Date: 2016
- Subjects: Fashion -- South Africa -- Port Elizabeth Costume design -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/11449 , vital:26926
- Description: The aim of this study is to illustrate how, in the design of costumes, adopting design elements used to produce conceptual fashion can create conceptual costumes that have the ability to express emotions. The play Sounds of South End (2013) contains such qualities; therefore it has been selected to illustrate how the mood and emotional trajectory of a play can be interpreted through symbolism. The play illustrates the life before and after the forced removals during the apartheid (1960s and 1970s), of a fictional family, the Dietrichs, who live in South End, a suburb in Port Elizabeth, South Africa. A focus on the nature of emotional changes experienced by the family has been used to determine the overall mood of the play, leading to a translation of the shifting mood through a collection of conceptual costumes. The final collection was exhibited as an installation artwork that is an interpretation of the altering moods and emotions that occur in the life of the Dietrich family as the play unfolds. The conceptual costumes have been constructed to imbue the narrative of the play with deep meaning by using symbolic elements, such as colour, texture and weight, to suggest the emotional trajectory within the play. The eight costumes portray the interrelated gradual decline and resultant deterioration of human relations experienced by the Dietrichs, from a contented state of harmonious living to a wounded state of despair.
- Full Text:
- Date Issued: 2016
- Authors: Chingosho, Vimbai
- Date: 2016
- Subjects: Fashion -- South Africa -- Port Elizabeth Costume design -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/11449 , vital:26926
- Description: The aim of this study is to illustrate how, in the design of costumes, adopting design elements used to produce conceptual fashion can create conceptual costumes that have the ability to express emotions. The play Sounds of South End (2013) contains such qualities; therefore it has been selected to illustrate how the mood and emotional trajectory of a play can be interpreted through symbolism. The play illustrates the life before and after the forced removals during the apartheid (1960s and 1970s), of a fictional family, the Dietrichs, who live in South End, a suburb in Port Elizabeth, South Africa. A focus on the nature of emotional changes experienced by the family has been used to determine the overall mood of the play, leading to a translation of the shifting mood through a collection of conceptual costumes. The final collection was exhibited as an installation artwork that is an interpretation of the altering moods and emotions that occur in the life of the Dietrich family as the play unfolds. The conceptual costumes have been constructed to imbue the narrative of the play with deep meaning by using symbolic elements, such as colour, texture and weight, to suggest the emotional trajectory within the play. The eight costumes portray the interrelated gradual decline and resultant deterioration of human relations experienced by the Dietrichs, from a contented state of harmonious living to a wounded state of despair.
- Full Text:
- Date Issued: 2016
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
Engendering the meaningful use of electronic medical records: a South African perspective
- Chipfumbu, Colletor Tendeukai
- Authors: Chipfumbu, Colletor Tendeukai
- Date: 2016
- Subjects: Electronic records -- South Africa -- Management Information storage and retrieval systems -- Management , Medical records -- South Africa Medical records -- Data processing
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/18420 , vital:28635
- Description: Theoretically, the use of Electronic Medical Records (EMRs) holds promise of numerous benefits in healthcare provision, including improvement in continuity of care, quality of care and safety. However, in practice, there is evidence that the adoption of electronic medical records has been slow and where adopted, often lacks meaningful use. Thus there is a clear dichotomy between the ambitions for EMR use and the reality of EMR implementation. In the USA, a legislative approach was taken to turn around the situation. Other countries such as Canada and European countries have followed suit (in their own way) to address the adoption and meaningful use of electronic medical records. The South African e-Health strategy and the National Health Normative Standards Framework for Interoperability in eHealth in South Africa documents both recommend the adoption of EMRs. Much work has been done to establish a baseline for standards to ensure interoperability and data portability of healthcare applications and data. However, even with the increased focus on e-Health, South Africa remains excessively reliant on paper-based medical records. Where health information technologies have been adopted, there is lack of coordination between and within provinces, leading to a multitude of systems and vendors. Thus there is a lack of systematic adoption and meaningful use of EMRs in South Africa. The main objective of this research is to develop the components required to engender meaningful use of electronic medical records in the South African healthcare context. The main contributors are identified as EMR certification and consistent, proper use of certified EMRs. Literature review, a Delphi study and logical argumentation are used to develop the relevant components for the South African healthcare context. The benefits of EMRs can only be realized through systematic adoption and meaningful use of EMRs, thus this research contributes to providing a road map for engendering the meaningful use of EMRs with the ultimate aim of improving healthcare in the South African healthcare landscape.
- Full Text:
- Date Issued: 2016
- Authors: Chipfumbu, Colletor Tendeukai
- Date: 2016
- Subjects: Electronic records -- South Africa -- Management Information storage and retrieval systems -- Management , Medical records -- South Africa Medical records -- Data processing
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/18420 , vital:28635
- Description: Theoretically, the use of Electronic Medical Records (EMRs) holds promise of numerous benefits in healthcare provision, including improvement in continuity of care, quality of care and safety. However, in practice, there is evidence that the adoption of electronic medical records has been slow and where adopted, often lacks meaningful use. Thus there is a clear dichotomy between the ambitions for EMR use and the reality of EMR implementation. In the USA, a legislative approach was taken to turn around the situation. Other countries such as Canada and European countries have followed suit (in their own way) to address the adoption and meaningful use of electronic medical records. The South African e-Health strategy and the National Health Normative Standards Framework for Interoperability in eHealth in South Africa documents both recommend the adoption of EMRs. Much work has been done to establish a baseline for standards to ensure interoperability and data portability of healthcare applications and data. However, even with the increased focus on e-Health, South Africa remains excessively reliant on paper-based medical records. Where health information technologies have been adopted, there is lack of coordination between and within provinces, leading to a multitude of systems and vendors. Thus there is a lack of systematic adoption and meaningful use of EMRs in South Africa. The main objective of this research is to develop the components required to engender meaningful use of electronic medical records in the South African healthcare context. The main contributors are identified as EMR certification and consistent, proper use of certified EMRs. Literature review, a Delphi study and logical argumentation are used to develop the relevant components for the South African healthcare context. The benefits of EMRs can only be realized through systematic adoption and meaningful use of EMRs, thus this research contributes to providing a road map for engendering the meaningful use of EMRs with the ultimate aim of improving healthcare in the South African healthcare landscape.
- Full Text:
- Date Issued: 2016
Diversity management practices at Lovedale College
- Authors: Chola, Zolani
- Date: 2014
- Subjects: Diversity in the workplace -- South Africa -- King William's Town , Public universities and colleges -- South Africa -- King William's Town
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9392 , http://hdl.handle.net/10948/d1021163
- Description: The global working environment has altered dramatically over the last decade and in particular, the workforce has begun to consist of many diverse individuals. The world has become a global marketplace, with boundaries between countries becoming increasingly vague and permeable. Advances in technology and the advent of a global economy have brought people from different countries closer together. Globalisation has precipitated many challenges in modern organisations, and one of these challenges is workforce diversity. Workforces in organisations differ in terms of gender, age, race, ethnicity and sexual orientation. Globally, countries are faced with the spiralling challenge of skills shortages and there is an expanding competition for skilled workers, specifically for those who possess scarce skills. This leads to an expatriation of skills, creating a natural increase in workforce diversity that expands beyond local ethnicity and language. This affects all organisations, including academic institutions such as universities, universities of technology and public further education and training colleges. Given this challenge organisations, educational institutions and other entities are investigating ways to better deal or serve their constituents. Lovedale PFET College is a public further education and training college that provides skills to young South Africans, specifically vocational related skills. The main research problem of this study was to identify the recommended diversity management best practices that characterise effective organisations and determine the extent to which these practices are applied at Lovedale PFET College. In order to address the problem, a theoretical study was conducted which focused on identifying the recommended diversity management best practices. In addition, interviews were conducted with managers at Lovedale College to gain an understanding of their perspective on diversity management. Based on the combined main points gleaned from theory and the interviews, a questionnaire was developed and administered to both academic and support staff at Lovedale PFET College to obtain their perceptions of the diversity practices and outcomes at the college. The results of the survey revealed that Lovedale PFET College could improve on the implementation of best practices in diversity management. Specifically, attention could be given to diversity education and training, and diversity management policies and procedures.
- Full Text:
- Date Issued: 2014
- Authors: Chola, Zolani
- Date: 2014
- Subjects: Diversity in the workplace -- South Africa -- King William's Town , Public universities and colleges -- South Africa -- King William's Town
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9392 , http://hdl.handle.net/10948/d1021163
- Description: The global working environment has altered dramatically over the last decade and in particular, the workforce has begun to consist of many diverse individuals. The world has become a global marketplace, with boundaries between countries becoming increasingly vague and permeable. Advances in technology and the advent of a global economy have brought people from different countries closer together. Globalisation has precipitated many challenges in modern organisations, and one of these challenges is workforce diversity. Workforces in organisations differ in terms of gender, age, race, ethnicity and sexual orientation. Globally, countries are faced with the spiralling challenge of skills shortages and there is an expanding competition for skilled workers, specifically for those who possess scarce skills. This leads to an expatriation of skills, creating a natural increase in workforce diversity that expands beyond local ethnicity and language. This affects all organisations, including academic institutions such as universities, universities of technology and public further education and training colleges. Given this challenge organisations, educational institutions and other entities are investigating ways to better deal or serve their constituents. Lovedale PFET College is a public further education and training college that provides skills to young South Africans, specifically vocational related skills. The main research problem of this study was to identify the recommended diversity management best practices that characterise effective organisations and determine the extent to which these practices are applied at Lovedale PFET College. In order to address the problem, a theoretical study was conducted which focused on identifying the recommended diversity management best practices. In addition, interviews were conducted with managers at Lovedale College to gain an understanding of their perspective on diversity management. Based on the combined main points gleaned from theory and the interviews, a questionnaire was developed and administered to both academic and support staff at Lovedale PFET College to obtain their perceptions of the diversity practices and outcomes at the college. The results of the survey revealed that Lovedale PFET College could improve on the implementation of best practices in diversity management. Specifically, attention could be given to diversity education and training, and diversity management policies and procedures.
- Full Text:
- Date Issued: 2014
Moderat's Rusty nails and Loie Fuller's Serpentine dance : analysis cloth, the body and movement as symbolic interpretation of meaning in film
- Authors: Coates, Maran
- Date: 2012
- Subjects: Fashion in motion pictures
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8498 , http://hdl.handle.net/10948/d1015733
- Description: The main objective of the study is to explore how cloth, the body and movement are able to communicate possible symbolic meaning in Loïe Fuller’s Serpentine Dance film and Moderat’s Rusty Nails music video. The study further attempts to establish the characteristics of fashion film to include cloth, the body and movement and provide a methodology that locates fashion film as a sign system using a visual semiotic analysis framework. The films were then compared and contrasted to determine similarities and differences in their use of cloth, the body and movement. The findings from the film analysis suggest that cloth, the body and movement communicate symbolic meaning in the films based on their associated meanings that are generated both inside and outside the film context. By focussing on cloth, the body and movement as primary communicators (rather than secondary or supporting communicators) in film, new meanings can be interpreted from their interrelationship. The results inform new ways for fashion designers and fashion filmmakers to engage with cloth, the body and movement in fashion film.
- Full Text:
- Date Issued: 2012
- Authors: Coates, Maran
- Date: 2012
- Subjects: Fashion in motion pictures
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8498 , http://hdl.handle.net/10948/d1015733
- Description: The main objective of the study is to explore how cloth, the body and movement are able to communicate possible symbolic meaning in Loïe Fuller’s Serpentine Dance film and Moderat’s Rusty Nails music video. The study further attempts to establish the characteristics of fashion film to include cloth, the body and movement and provide a methodology that locates fashion film as a sign system using a visual semiotic analysis framework. The films were then compared and contrasted to determine similarities and differences in their use of cloth, the body and movement. The findings from the film analysis suggest that cloth, the body and movement communicate symbolic meaning in the films based on their associated meanings that are generated both inside and outside the film context. By focussing on cloth, the body and movement as primary communicators (rather than secondary or supporting communicators) in film, new meanings can be interpreted from their interrelationship. The results inform new ways for fashion designers and fashion filmmakers to engage with cloth, the body and movement in fashion film.
- Full Text:
- Date Issued: 2012
A framework for information security governance in SMMEs
- Authors: Coertze, Jacques Jacobus
- Date: 2012
- Subjects: Business -- Data processing -- Security measures , Management information systems -- Security measures , Computer networks -- Security measures
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9810 , http://hdl.handle.net/10948/d1014083
- Description: It has been found that many small, medium and micro-sized enterprises (SMMEs) do not comply with sound information security governance principles, specifically the principles involved in drafting information security policies and monitoring compliance, mainly as a result of restricted resources and expertise. Research suggests that this problem occurs worldwide and that the impact it has on SMMEs is great. The problem is further compounded by the fact that, in our modern-day information technology environment, many larger organisations are providing SMMEs with access to their networks. This results not only in SMMEs being exposed to security risks, but the larger organisations as well. In previous research an information security management framework and toolbox was developed to assist SMMEs in drafting information security policies. Although this research was of some help to SMMEs, further research has shown that an even greater problem exists with the governance of information security as a result of the advancements that have been identified in information security literature. The aim of this dissertation is therefore to establish an information security governance framework that requires minimal effort and little expertise to alleviate governance problems. It is believed that such a framework would be useful for SMMEs and would result in the improved implementation of information security governance.
- Full Text:
- Date Issued: 2012
- Authors: Coertze, Jacques Jacobus
- Date: 2012
- Subjects: Business -- Data processing -- Security measures , Management information systems -- Security measures , Computer networks -- Security measures
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9810 , http://hdl.handle.net/10948/d1014083
- Description: It has been found that many small, medium and micro-sized enterprises (SMMEs) do not comply with sound information security governance principles, specifically the principles involved in drafting information security policies and monitoring compliance, mainly as a result of restricted resources and expertise. Research suggests that this problem occurs worldwide and that the impact it has on SMMEs is great. The problem is further compounded by the fact that, in our modern-day information technology environment, many larger organisations are providing SMMEs with access to their networks. This results not only in SMMEs being exposed to security risks, but the larger organisations as well. In previous research an information security management framework and toolbox was developed to assist SMMEs in drafting information security policies. Although this research was of some help to SMMEs, further research has shown that an even greater problem exists with the governance of information security as a result of the advancements that have been identified in information security literature. The aim of this dissertation is therefore to establish an information security governance framework that requires minimal effort and little expertise to alleviate governance problems. It is believed that such a framework would be useful for SMMEs and would result in the improved implementation of information security governance.
- Full Text:
- Date Issued: 2012
Handheld infrared CO2 gas detector
- Authors: Coetzee, George
- Date: 2000
- Subjects: Gas-detectors , Infrared detectors , Water quality -- Measurement
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10807 , http://hdl.handle.net/10948/28 , Gas-detectors , Infrared detectors , Water quality -- Measurement
- Description: A handheld InfraRed (IR) Carbon Dioxide (CO2) gas detector was developed and used to carry out a study of water and urine samples in South Africa. The details of the model and the results of the study are discussed here. The overseas markets are not geared for the current South African conditions. Use is made of components that can be obtained locally. Imported components are very expensive and should an imported model be damaged, it has to be returned overseas to be repaired. As an illustration of this technology it was decided to perform research in water technology and then develope a handheld Infrared CO2 gas detector based prototype which would: highlight the benefits of using handheld IR CO2 gas detectors; be built locally; be powered by a 12 Volt supply; be very easy to maintain; and be cost effective. Experimental results on the accuracy and stability of the instrument formed part of this study. The IR CO2 Gas detector that was developed was used throughout the project as a prototype and testing vehicle for numerous designs. It proved to be superior to the current imported commercial instruments in terms of size, cost effectiveness and user friendliness. A further advantage of the instrument is its robustness.
- Full Text:
- Date Issued: 2000
- Authors: Coetzee, George
- Date: 2000
- Subjects: Gas-detectors , Infrared detectors , Water quality -- Measurement
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10807 , http://hdl.handle.net/10948/28 , Gas-detectors , Infrared detectors , Water quality -- Measurement
- Description: A handheld InfraRed (IR) Carbon Dioxide (CO2) gas detector was developed and used to carry out a study of water and urine samples in South Africa. The details of the model and the results of the study are discussed here. The overseas markets are not geared for the current South African conditions. Use is made of components that can be obtained locally. Imported components are very expensive and should an imported model be damaged, it has to be returned overseas to be repaired. As an illustration of this technology it was decided to perform research in water technology and then develope a handheld Infrared CO2 gas detector based prototype which would: highlight the benefits of using handheld IR CO2 gas detectors; be built locally; be powered by a 12 Volt supply; be very easy to maintain; and be cost effective. Experimental results on the accuracy and stability of the instrument formed part of this study. The IR CO2 Gas detector that was developed was used throughout the project as a prototype and testing vehicle for numerous designs. It proved to be superior to the current imported commercial instruments in terms of size, cost effectiveness and user friendliness. A further advantage of the instrument is its robustness.
- Full Text:
- Date Issued: 2000
'n Kritiese evaluering na die effektiwiteit van bestuurstrategieë vir ekstensiewe wolskaapboerdery in die groter Burgersdorp omgewing
- Authors: Coetzee, Johanna Magdalena
- Date: 2002
- Subjects: Sheep ranches -- South Africa -- Burgersdorp -- Management , Sheep industry -- South Africa -- Burgersdorp
- Language: Afrikaans
- Type: Thesis , Masters , MTech
- Identifier: vital:10953 , http://hdl.handle.net/10948/109 , Sheep ranches -- South Africa -- Burgersdorp -- Management , Sheep industry -- South Africa -- Burgersdorp
- Description: The main objectives of this study can be divided into three categories. In the first place it refers to the determination of production- and reproduction norms for the different main production areas in the greater Burgersdorp area, to promote production. In the second place it refers to the determination of the different management styles of sheep farmers in the greater Burgersdorp area. In the third place it refers to the calculation of gross margins for sheep farming in the greater Burgersdorp area, to establish the sustainable economic position. The survey area (the greater Burgersdorp area) includes the magisterial districts of Burgersdorp, Molteno, Steynsburg and Venterstad. The four magisterial districts were divided into two main production areas namely Stormberg Highveld and Burgersdorp Lowveld. Stormberg Highveld includes Molteno and the high-lying area (highveld) of Burgersdorp. Burgersdorp Lowveld comprises Steynsburg, Venterstad and the low-lying area (lowveld) of Burgersdorp. The management strategies of sheep farmers in the survey area were determined by means of a questionnaire and statistically analysed. The economic analyses of the sheep industry (wool and meat) were performed with the Geyer computer model. In this study it showed that the Dorper farmers obtained the highest gross margin per sheep. The lowest gross margin per sheep resulted from the Vleismerino farmers. Although the composition of the gross production value and the directly allocatable variable costs compare favourably, each main production area has unique management strategies for the different sheep breeds. The different management strategies can serve as the norm for extensive sheep farming, applicable to the specific main production area.
- Full Text:
- Date Issued: 2002
- Authors: Coetzee, Johanna Magdalena
- Date: 2002
- Subjects: Sheep ranches -- South Africa -- Burgersdorp -- Management , Sheep industry -- South Africa -- Burgersdorp
- Language: Afrikaans
- Type: Thesis , Masters , MTech
- Identifier: vital:10953 , http://hdl.handle.net/10948/109 , Sheep ranches -- South Africa -- Burgersdorp -- Management , Sheep industry -- South Africa -- Burgersdorp
- Description: The main objectives of this study can be divided into three categories. In the first place it refers to the determination of production- and reproduction norms for the different main production areas in the greater Burgersdorp area, to promote production. In the second place it refers to the determination of the different management styles of sheep farmers in the greater Burgersdorp area. In the third place it refers to the calculation of gross margins for sheep farming in the greater Burgersdorp area, to establish the sustainable economic position. The survey area (the greater Burgersdorp area) includes the magisterial districts of Burgersdorp, Molteno, Steynsburg and Venterstad. The four magisterial districts were divided into two main production areas namely Stormberg Highveld and Burgersdorp Lowveld. Stormberg Highveld includes Molteno and the high-lying area (highveld) of Burgersdorp. Burgersdorp Lowveld comprises Steynsburg, Venterstad and the low-lying area (lowveld) of Burgersdorp. The management strategies of sheep farmers in the survey area were determined by means of a questionnaire and statistically analysed. The economic analyses of the sheep industry (wool and meat) were performed with the Geyer computer model. In this study it showed that the Dorper farmers obtained the highest gross margin per sheep. The lowest gross margin per sheep resulted from the Vleismerino farmers. Although the composition of the gross production value and the directly allocatable variable costs compare favourably, each main production area has unique management strategies for the different sheep breeds. The different management strategies can serve as the norm for extensive sheep farming, applicable to the specific main production area.
- Full Text:
- Date Issued: 2002
A study of lanthanide complexes with di-2-pyridyl ligands
- Authors: Coetzee, Louis-Charl Cloete
- Date: 2016
- Subjects: Rare earth metals
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/4731 , vital:20659
- Description: The ligands di(2-pyridyl) ketone (DPK) and cis-1,2 di(2-pyridyl) ethylene (DPE) are N,N,Odonor ligands that can undergo nucleophilic addition and become more flexible for coordination. The reaction between the lanthanide thiocyanate salt and DPK gave rise to seven novel complexes of the general formula [Ln(NCS)3(DPKOH)3], where Ln = La, Ce, Nd, Eu, Tb, Dy and Ho. 1H NMR spectroscopy verified that the ligand underwent nucleophilic addition upon coordination. This was further confirmed using UV-Vis spectroscopy which showed a shift in the absorption bands due to conjugation of electrons within the pyridyl ring upon coordination. UV-Vis spectroscopy was also utilised to test the covalent character of the neodymium and holmium complexes. X-ray diffraction and IR spectroscopy showed that three DPK ligands coordinated bidentately through a pyridinic nitrogen and a hydroxyl oxygen, while three isothiocyanato molecules completed the coordination environment around each metal. Furthermore, X-ray diffraction also revealed that these complexes are isostructural, ninecoordinate and the polyhedron which encloses each ion is of trigonal tricapped prismatic shape with D3h symmetry. Micro-analysis on all the complexes, except lanthanum and holmium confirmed the molecular formulae produced from the crystallographic data of each complex. The reaction between the lanthanide thiocyanate salt and DPE produced poor quality crystals which could not be detected by X-ray diffraction. The lanthanide salts used for this reaction were lanthanum, neodymium, europium, dysprosium and holmium. Upon coordination, conductivity measurements detected the presence of lanthanide ions in each solution. 1H NMR and IR spectroscopic studies showed that the ethylenic moiety of DPE underwent nucleophilic addition upon coordination. UV-Vis spectroscopy further confirmed nucleophilic addition upon coordination due to shifts in absorption bands. IR spectroscopy verified the possibility of a bidentate coordination to each metal through a pyridinic nitrogen and a hydroxyl oxygen as well as a monodentate coordination through isothiocyanato ligands. A micro-analysis on all the complexes provided the molecular formulae that can best fit each complex. The effect of the solvent molecules on the bonding parameters of the lanthanum complex was investigated. An analysis of the results produced from crystallographic data revealed the presence of intermolecular forces which interacted and stabilised the complex.
- Full Text:
- Date Issued: 2016
- Authors: Coetzee, Louis-Charl Cloete
- Date: 2016
- Subjects: Rare earth metals
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/4731 , vital:20659
- Description: The ligands di(2-pyridyl) ketone (DPK) and cis-1,2 di(2-pyridyl) ethylene (DPE) are N,N,Odonor ligands that can undergo nucleophilic addition and become more flexible for coordination. The reaction between the lanthanide thiocyanate salt and DPK gave rise to seven novel complexes of the general formula [Ln(NCS)3(DPKOH)3], where Ln = La, Ce, Nd, Eu, Tb, Dy and Ho. 1H NMR spectroscopy verified that the ligand underwent nucleophilic addition upon coordination. This was further confirmed using UV-Vis spectroscopy which showed a shift in the absorption bands due to conjugation of electrons within the pyridyl ring upon coordination. UV-Vis spectroscopy was also utilised to test the covalent character of the neodymium and holmium complexes. X-ray diffraction and IR spectroscopy showed that three DPK ligands coordinated bidentately through a pyridinic nitrogen and a hydroxyl oxygen, while three isothiocyanato molecules completed the coordination environment around each metal. Furthermore, X-ray diffraction also revealed that these complexes are isostructural, ninecoordinate and the polyhedron which encloses each ion is of trigonal tricapped prismatic shape with D3h symmetry. Micro-analysis on all the complexes, except lanthanum and holmium confirmed the molecular formulae produced from the crystallographic data of each complex. The reaction between the lanthanide thiocyanate salt and DPE produced poor quality crystals which could not be detected by X-ray diffraction. The lanthanide salts used for this reaction were lanthanum, neodymium, europium, dysprosium and holmium. Upon coordination, conductivity measurements detected the presence of lanthanide ions in each solution. 1H NMR and IR spectroscopic studies showed that the ethylenic moiety of DPE underwent nucleophilic addition upon coordination. UV-Vis spectroscopy further confirmed nucleophilic addition upon coordination due to shifts in absorption bands. IR spectroscopy verified the possibility of a bidentate coordination to each metal through a pyridinic nitrogen and a hydroxyl oxygen as well as a monodentate coordination through isothiocyanato ligands. A micro-analysis on all the complexes provided the molecular formulae that can best fit each complex. The effect of the solvent molecules on the bonding parameters of the lanthanum complex was investigated. An analysis of the results produced from crystallographic data revealed the presence of intermolecular forces which interacted and stabilised the complex.
- Full Text:
- Date Issued: 2016
Application of Pascale's constructive 'conflict paradigm' to consider transformation efforts at a selected bank with particular attention to the ATM devision
- Authors: Coetzer, Gary
- Date: 2001
- Subjects: Organizational change , Banks and banking -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10843 , http://hdl.handle.net/10948/39 , Organizational change , Banks and banking -- South Africa
- Description: In applying Pascale’s (1990) constructive ‘conflict paradigm’ to consider transformation efforts at a selected bank, this study argues that transformation could be sustained if the organisation were to self-reflect on the paradoxes that are generated when constructive conflict is encouraged. Underlying this supposition is the notion of “disequilibrium” which supports creative tension within organisations and prompts inquiry and dialogue, leading to the new. Sustaining disequilibrium allows an organisation to develop the “requisite internal variety” in order to meet the challenges in its environment. Key to encouraging this form of organisational resilience to its environment is the nature of the organisation’s culture or context. Johnson’s (1998) “cultural web” is used to analyse the culture of the selected bank and “re-map” the culture in line with the bank’s transformation strategies. Pascale’s seven domains of contention are applied with particular emphasis on the ATM division in order to develop a profile of conflict in the organisation.
- Full Text:
- Date Issued: 2001
- Authors: Coetzer, Gary
- Date: 2001
- Subjects: Organizational change , Banks and banking -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10843 , http://hdl.handle.net/10948/39 , Organizational change , Banks and banking -- South Africa
- Description: In applying Pascale’s (1990) constructive ‘conflict paradigm’ to consider transformation efforts at a selected bank, this study argues that transformation could be sustained if the organisation were to self-reflect on the paradoxes that are generated when constructive conflict is encouraged. Underlying this supposition is the notion of “disequilibrium” which supports creative tension within organisations and prompts inquiry and dialogue, leading to the new. Sustaining disequilibrium allows an organisation to develop the “requisite internal variety” in order to meet the challenges in its environment. Key to encouraging this form of organisational resilience to its environment is the nature of the organisation’s culture or context. Johnson’s (1998) “cultural web” is used to analyse the culture of the selected bank and “re-map” the culture in line with the bank’s transformation strategies. Pascale’s seven domains of contention are applied with particular emphasis on the ATM division in order to develop a profile of conflict in the organisation.
- Full Text:
- Date Issued: 2001
Attitudes towards hunting amongst the economically active public in Port Elizabeth
- Coetzer, Wentzel Christoffel
- Authors: Coetzer, Wentzel Christoffel
- Date: 2010
- Subjects: Hunting -- South Africa -- Port Elizabeth , Wildlife management -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10746 , http://hdl.handle.net/10948/1507 , Hunting -- South Africa -- Port Elizabeth , Wildlife management -- South Africa -- Port Elizabeth
- Description: Wildlife ranching is recognized as one of the important agricultural industries in South Africa, with hunting being the primary segment of the game industry. Hunting is an essential part of wildlife management and it contributes significantly to the conservation of biodiversity and to the economy. Despite this, the social acceptability of hunting is often questioned and negative attitudes towards hunting within the larger society may become a potential threat to the hunting industry. This may jeopardize the effective management of game and have a negative impact on conservation and the economy. This study is an empirical investigation of the attitudes of the economically active public in Port Elizabeth towards hunting. The objectives of this study are to investigate the nature and extent of the public's attitudes towards hunting, as well as to identify factors influencing the public's attitudes towards hunting. The study commenced with the establishment of a theoretical framework, based on a literature study on the psychology of human perceptions and attitudes towards hunting. The theoretical framework was then used to develop the empirical component of the study. A survey was conducted amongst a statistically representative sample of the economically active public in Port Elizabeth during 2009. The data was collected by means of personal interviews and self-administered questionnaires were used as the survey instrument. The study found that the economically active public in Port Elizabeth generally holds favourable attitudes towards hunting, with only a small proportion of the population wanting to ban hunting. The belief that hunting endangers wildlife was the most prominent reason for opposing hunting. Negative attitudes towards hunting were largely based on incorrect beliefs regarding hunting. The extent of a person's knowledge of hunting and exposure to hunting, as well as a person's social ties had a significant influence on their attitudes towards hunting.
- Full Text:
- Date Issued: 2010
- Authors: Coetzer, Wentzel Christoffel
- Date: 2010
- Subjects: Hunting -- South Africa -- Port Elizabeth , Wildlife management -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10746 , http://hdl.handle.net/10948/1507 , Hunting -- South Africa -- Port Elizabeth , Wildlife management -- South Africa -- Port Elizabeth
- Description: Wildlife ranching is recognized as one of the important agricultural industries in South Africa, with hunting being the primary segment of the game industry. Hunting is an essential part of wildlife management and it contributes significantly to the conservation of biodiversity and to the economy. Despite this, the social acceptability of hunting is often questioned and negative attitudes towards hunting within the larger society may become a potential threat to the hunting industry. This may jeopardize the effective management of game and have a negative impact on conservation and the economy. This study is an empirical investigation of the attitudes of the economically active public in Port Elizabeth towards hunting. The objectives of this study are to investigate the nature and extent of the public's attitudes towards hunting, as well as to identify factors influencing the public's attitudes towards hunting. The study commenced with the establishment of a theoretical framework, based on a literature study on the psychology of human perceptions and attitudes towards hunting. The theoretical framework was then used to develop the empirical component of the study. A survey was conducted amongst a statistically representative sample of the economically active public in Port Elizabeth during 2009. The data was collected by means of personal interviews and self-administered questionnaires were used as the survey instrument. The study found that the economically active public in Port Elizabeth generally holds favourable attitudes towards hunting, with only a small proportion of the population wanting to ban hunting. The belief that hunting endangers wildlife was the most prominent reason for opposing hunting. Negative attitudes towards hunting were largely based on incorrect beliefs regarding hunting. The extent of a person's knowledge of hunting and exposure to hunting, as well as a person's social ties had a significant influence on their attitudes towards hunting.
- Full Text:
- Date Issued: 2010
Implementing an activity-based costing model
- Authors: Cohen, Howard
- Date: 2004
- Subjects: Activity-based costing , Managerial accounting
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8970 , http://hdl.handle.net/10948/240 , Activity-based costing , Managerial accounting
- Description: Activity-based costing (ABC) is a forward-looking product costing method. Unlike traditional volume-based approaches, which are historically oriented, ABC concepts guide managers in seeking the best strategies to pursue in the future. This product costing method can be a valuable tool in planning and managing costs not only in the manufacturing area, but also in all aspects of business operations, from product design to distribution. Although its main advantage is its ability to provide more realistic product cost information for financial reporting purposes, use of ABC can lead to a better understanding of the strategic linkages existing between the various cost areas in the organisation. It enables managers to have a holistic view of cost management. ABC was developed to better understand, manage and control the overheads. The brief fundamental of ABC is: Products consume activities, activities consume resources, and resources consume costs. Based upon this fundamental principle, ABC can trace the cost from resources to activities that are consumed by product manufacturing processes as well as from activities to products. ABC investigates the transactions that trigger cost instead of concentrating solely on measures of physical volume or a certain amount of labour hours. Compared to the traditional costing systems, ABC can not only answer how much product cost is but also tell executives the factors triggering costs and the way to manage costs. ABC helps managers make better decisions about product design, pricing, marketing, and mix and encourages continual improvement. Unlike the traditional method, instead of using the single pre-determined overhead rate to absorb the indirect cost to products, ABC uses actual incurred cost to v determine the product cost. By tracing the absorption process of indirect cost, ABC would provide more information to management and help it find better ways to manage costs. However, the cost drivers used in ABC are constants but the cost driver rates are continually changing. ABC still uses predetermined cost drivers so it has the same fundamental problem as the traditional methods for estimating.
- Full Text:
- Date Issued: 2004
- Authors: Cohen, Howard
- Date: 2004
- Subjects: Activity-based costing , Managerial accounting
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8970 , http://hdl.handle.net/10948/240 , Activity-based costing , Managerial accounting
- Description: Activity-based costing (ABC) is a forward-looking product costing method. Unlike traditional volume-based approaches, which are historically oriented, ABC concepts guide managers in seeking the best strategies to pursue in the future. This product costing method can be a valuable tool in planning and managing costs not only in the manufacturing area, but also in all aspects of business operations, from product design to distribution. Although its main advantage is its ability to provide more realistic product cost information for financial reporting purposes, use of ABC can lead to a better understanding of the strategic linkages existing between the various cost areas in the organisation. It enables managers to have a holistic view of cost management. ABC was developed to better understand, manage and control the overheads. The brief fundamental of ABC is: Products consume activities, activities consume resources, and resources consume costs. Based upon this fundamental principle, ABC can trace the cost from resources to activities that are consumed by product manufacturing processes as well as from activities to products. ABC investigates the transactions that trigger cost instead of concentrating solely on measures of physical volume or a certain amount of labour hours. Compared to the traditional costing systems, ABC can not only answer how much product cost is but also tell executives the factors triggering costs and the way to manage costs. ABC helps managers make better decisions about product design, pricing, marketing, and mix and encourages continual improvement. Unlike the traditional method, instead of using the single pre-determined overhead rate to absorb the indirect cost to products, ABC uses actual incurred cost to v determine the product cost. By tracing the absorption process of indirect cost, ABC would provide more information to management and help it find better ways to manage costs. However, the cost drivers used in ABC are constants but the cost driver rates are continually changing. ABC still uses predetermined cost drivers so it has the same fundamental problem as the traditional methods for estimating.
- Full Text:
- Date Issued: 2004
SecMVC : a model for secure software design based on the model-view-controller pattern
- Authors: Colesky, Michael Robert
- Date: 2014
- Subjects: Computer networks -- Security measures -- Software , Computer software -- Development , Model-driven software architecture
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9823 , http://hdl.handle.net/10948/d1020614
- Description: Current advances in the software development industry are growing more ubiquitous by the day. This has caused for security, not only in the broader sense, but specifically within the design and overall development of software itself, to become all the more important. An evidently prevalent problem in the domain of software development is that software security is not consistently addressed during design, which undermines core security concerns, and leads to the development of insecure software. This research seeks to address this issue via a model for secure software design, which is based on a software design pattern, namely, the Model-View-Controller (MVC) pattern. The use of a pattern to convey knowledge is not a new notion. However, the ability of software design patterns to convey secure software design is an idea worth investigating. Following identification of secure software design principles and concepts, as well as software design patterns, specifically those relating to the MVC pattern, a model was designed and developed. With the MVC pattern argued as being a suitable foundation for the model, the security conscious MVC (SecMVC) combines secure software design principles and concepts into the MVC pattern. Together herewith, the MVC pattern’s components in the MVC Compound pattern, namely: the Observer pattern, the Strategy pattern, and the Composite pattern, have provided further sub-models for less abstraction and greater detail. These sub-models were developed, as a result of the SecMVC model’s evaluation in the validation for this study, an expert review. Argued in the light of similar research methods, the expert review was chosen – along with a process that included the use of two expert participants to validate the SecMVC model. It was determined through the expert review that the SecMVC model is of sufficient utility, quality, and efficacy to constitute research value. The research methodology process followed was design science, in which the SecMVC model, which includes its related sub-models, serves as the artefact and research output of this study. This research study contributes evidence of the feasibility for integrating knowledge into software design patterns. This includes the SecMVC model itself. In addition, it argues for the use of an expert review, as an evaluative research method for such an artifact.
- Full Text:
- Date Issued: 2014
- Authors: Colesky, Michael Robert
- Date: 2014
- Subjects: Computer networks -- Security measures -- Software , Computer software -- Development , Model-driven software architecture
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9823 , http://hdl.handle.net/10948/d1020614
- Description: Current advances in the software development industry are growing more ubiquitous by the day. This has caused for security, not only in the broader sense, but specifically within the design and overall development of software itself, to become all the more important. An evidently prevalent problem in the domain of software development is that software security is not consistently addressed during design, which undermines core security concerns, and leads to the development of insecure software. This research seeks to address this issue via a model for secure software design, which is based on a software design pattern, namely, the Model-View-Controller (MVC) pattern. The use of a pattern to convey knowledge is not a new notion. However, the ability of software design patterns to convey secure software design is an idea worth investigating. Following identification of secure software design principles and concepts, as well as software design patterns, specifically those relating to the MVC pattern, a model was designed and developed. With the MVC pattern argued as being a suitable foundation for the model, the security conscious MVC (SecMVC) combines secure software design principles and concepts into the MVC pattern. Together herewith, the MVC pattern’s components in the MVC Compound pattern, namely: the Observer pattern, the Strategy pattern, and the Composite pattern, have provided further sub-models for less abstraction and greater detail. These sub-models were developed, as a result of the SecMVC model’s evaluation in the validation for this study, an expert review. Argued in the light of similar research methods, the expert review was chosen – along with a process that included the use of two expert participants to validate the SecMVC model. It was determined through the expert review that the SecMVC model is of sufficient utility, quality, and efficacy to constitute research value. The research methodology process followed was design science, in which the SecMVC model, which includes its related sub-models, serves as the artefact and research output of this study. This research study contributes evidence of the feasibility for integrating knowledge into software design patterns. This includes the SecMVC model itself. In addition, it argues for the use of an expert review, as an evaluative research method for such an artifact.
- Full Text:
- Date Issued: 2014
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
The influence of 1950s fashion photographers, Richard Avedon and Irving Penn, on photographers Matthew Rolston and Steven Meisel
- Authors: Cordier, Astrid
- Date: 2011
- Subjects: Fashion photpgraphy , Photographers -- United States
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8496 , http://hdl.handle.net/10948/d1008112 , Fashion photpgraphy , Photographers -- United States
- Description: Photography has been used to record and document periods in time, which Wells (2001:19) acknowledges by stating that, “…photographs are records and documents which pin down the changing world of appearance”. Richard Avedon and Irving Penn made a significant contribution to fashion photography during the 1950s but this has seldom been explored in a scholarly way. By defining the characteristics of Avedon and Penn’s work, a possible understanding of their influence on contemporary fashion photographers, Matthew Rolston and Steven Meisel may be determined and so expand on the understanding of the contribution of Avedon and Penn to contemporary fashion photography. Avedon, Penn, Rolston and Meisel’s fashion photographs will be visually analysed to show the similarities and the relevance of 1950s fashion photography to contemporary fashion photography. Paul Martin Lester’s (2003) method of visual analysis will be used as the basis for this analysis. The reason for choosing Lester’s methods of visual analysis is that it can be applied to all fields of visual art and design. Contemporary fashion photography draws on many different stylistic devices and periods in history for its re-invention, so it is important to understand what constitutes the defining characteristics of a stylistic period in history to be able to revisit it in contemporary photography.
- Full Text:
- Date Issued: 2011
- Authors: Cordier, Astrid
- Date: 2011
- Subjects: Fashion photpgraphy , Photographers -- United States
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:8496 , http://hdl.handle.net/10948/d1008112 , Fashion photpgraphy , Photographers -- United States
- Description: Photography has been used to record and document periods in time, which Wells (2001:19) acknowledges by stating that, “…photographs are records and documents which pin down the changing world of appearance”. Richard Avedon and Irving Penn made a significant contribution to fashion photography during the 1950s but this has seldom been explored in a scholarly way. By defining the characteristics of Avedon and Penn’s work, a possible understanding of their influence on contemporary fashion photographers, Matthew Rolston and Steven Meisel may be determined and so expand on the understanding of the contribution of Avedon and Penn to contemporary fashion photography. Avedon, Penn, Rolston and Meisel’s fashion photographs will be visually analysed to show the similarities and the relevance of 1950s fashion photography to contemporary fashion photography. Paul Martin Lester’s (2003) method of visual analysis will be used as the basis for this analysis. The reason for choosing Lester’s methods of visual analysis is that it can be applied to all fields of visual art and design. Contemporary fashion photography draws on many different stylistic devices and periods in history for its re-invention, so it is important to understand what constitutes the defining characteristics of a stylistic period in history to be able to revisit it in contemporary photography.
- Full Text:
- Date Issued: 2011
The management of extralimital giraffe (Giraffa Camelopardalis) in the mosaic thicket of Southern Cape, South Africa
- Authors: Cornelius, Andri Judith
- Date: 2010
- Subjects: Giraffe -- South Africa -- Eastern Cape , Giraffe -- Food -- South Africa -- Eastern Cape , Giraffe -- Ecology -- South Africa -- Eastern Cape , Animal behavior , Animal-plant relationships -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10749 , http://hdl.handle.net/10948/1345 , Giraffe -- South Africa -- Eastern Cape , Giraffe -- Food -- South Africa -- Eastern Cape , Giraffe -- Ecology -- South Africa -- Eastern Cape , Animal behavior , Animal-plant relationships -- South Africa -- Eastern Cape
- Description: The giraffe at Nyaru were found to be browsers who made little use of graze during the study period. They utilized a diversity of 20 browse species. Two species, Acacia karroo and Acacia cyclops, formed the bulk of the giraffe diet throughout the year. A definite seasonal dietary shift was evident. A. karroo was favoured in summer and autumn and formed the main food species in spring, summer and autumn. A. cyclops was favoured throughout the study, but its contribution to the diet increased during winter when less A. karroo was consumed. This seasonal shift is related to the deciduous nature of Acacia karroo. Although a seasonal shift in species contribution to giraffe diet has been observed in many other giraffe feeding studies, no studies on giraffe feeding have been done in the Mosaic Thicket of the southern Cape. The ecological browsing capacity for giraffe in thicket was estimated to be between 0.020 BU/ha and 0.095 BU/ha. The browsing capacity for giraffe at Nyaru, based on the available phytomass 2–5 m above the ground, was estimated using those species that formed the bulk of the giraffe diet, and amounted to 0.063 BU/ha. A maximum of three giraffe could thus be stocked on the 157 ha of suitable giraffe habitat on Nyaru. This stocking rate recommendation lies within the range commonly recommended by local consultants for giraffe introductions into the southern Cape. Their recommendations are, however, not based on quantitative assessments such as performed in this study. The recommendation of this study should not be applied as a fixed ecological capacity for giraffe in thicket, but should be seen as a starting point in the adaptive management cycle. Ongoing monitoring of parameters, such as herbaceous composition and phytomass; as well as the condition of key browse species, is strongly advocated. A. karroo was browsed significantly more and carried significantly fewer pods per tree at a heavily used site compared to a lightly used site. Heavy browsing thus appears to affect the reproductive success of A. karroo significantly. Fewer pods are likely to lead to lower regeneration and thus reduced density of A. karroo. Whether A. karroo will maintain its dominance within the thicket vii community in the long run will be related to how individual plants survive and reproduce and if some can escape from herbivory. Fewer G. occidentalis were clumped with other species at the heavily used site compared to the lightly used site. This could possibly be attributed to the fact that intense browsing pressure at the heavily used site caused protective clumps to be eaten away, thus exposing G. occidentalis to higher ungulate browsing. Previous studies have found that nurse shrubs protect G. occidentalis against ungulate browsing. G. occidentalis was browsed significantly more at the heavily used site compared to the lightly used site. There was a general trend of fewer fruits at the heavily used site compared to the lightly used site, while fruits were absent on G. occidentalis growing alone at the heavily used site. This suggests a negative effect of heavy browsing on plant reproductive success and emphasizes the importance of nurse plants for the successful recruitment and hence long term prevalence of G. occidentalis in Mosaic Thicket.
- Full Text:
- Date Issued: 2010
- Authors: Cornelius, Andri Judith
- Date: 2010
- Subjects: Giraffe -- South Africa -- Eastern Cape , Giraffe -- Food -- South Africa -- Eastern Cape , Giraffe -- Ecology -- South Africa -- Eastern Cape , Animal behavior , Animal-plant relationships -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:10749 , http://hdl.handle.net/10948/1345 , Giraffe -- South Africa -- Eastern Cape , Giraffe -- Food -- South Africa -- Eastern Cape , Giraffe -- Ecology -- South Africa -- Eastern Cape , Animal behavior , Animal-plant relationships -- South Africa -- Eastern Cape
- Description: The giraffe at Nyaru were found to be browsers who made little use of graze during the study period. They utilized a diversity of 20 browse species. Two species, Acacia karroo and Acacia cyclops, formed the bulk of the giraffe diet throughout the year. A definite seasonal dietary shift was evident. A. karroo was favoured in summer and autumn and formed the main food species in spring, summer and autumn. A. cyclops was favoured throughout the study, but its contribution to the diet increased during winter when less A. karroo was consumed. This seasonal shift is related to the deciduous nature of Acacia karroo. Although a seasonal shift in species contribution to giraffe diet has been observed in many other giraffe feeding studies, no studies on giraffe feeding have been done in the Mosaic Thicket of the southern Cape. The ecological browsing capacity for giraffe in thicket was estimated to be between 0.020 BU/ha and 0.095 BU/ha. The browsing capacity for giraffe at Nyaru, based on the available phytomass 2–5 m above the ground, was estimated using those species that formed the bulk of the giraffe diet, and amounted to 0.063 BU/ha. A maximum of three giraffe could thus be stocked on the 157 ha of suitable giraffe habitat on Nyaru. This stocking rate recommendation lies within the range commonly recommended by local consultants for giraffe introductions into the southern Cape. Their recommendations are, however, not based on quantitative assessments such as performed in this study. The recommendation of this study should not be applied as a fixed ecological capacity for giraffe in thicket, but should be seen as a starting point in the adaptive management cycle. Ongoing monitoring of parameters, such as herbaceous composition and phytomass; as well as the condition of key browse species, is strongly advocated. A. karroo was browsed significantly more and carried significantly fewer pods per tree at a heavily used site compared to a lightly used site. Heavy browsing thus appears to affect the reproductive success of A. karroo significantly. Fewer pods are likely to lead to lower regeneration and thus reduced density of A. karroo. Whether A. karroo will maintain its dominance within the thicket vii community in the long run will be related to how individual plants survive and reproduce and if some can escape from herbivory. Fewer G. occidentalis were clumped with other species at the heavily used site compared to the lightly used site. This could possibly be attributed to the fact that intense browsing pressure at the heavily used site caused protective clumps to be eaten away, thus exposing G. occidentalis to higher ungulate browsing. Previous studies have found that nurse shrubs protect G. occidentalis against ungulate browsing. G. occidentalis was browsed significantly more at the heavily used site compared to the lightly used site. There was a general trend of fewer fruits at the heavily used site compared to the lightly used site, while fruits were absent on G. occidentalis growing alone at the heavily used site. This suggests a negative effect of heavy browsing on plant reproductive success and emphasizes the importance of nurse plants for the successful recruitment and hence long term prevalence of G. occidentalis in Mosaic Thicket.
- Full Text:
- Date Issued: 2010