Advanced monitoring system for bolted connections in vehicle construction
- Authors: Buchmann, Macro
- Date: 2010
- Subjects: Automobiles -- Design and construction , Motor vehicles -- Design and construction , Bolted joints
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9617 , http://hdl.handle.net/10948/1417 , Automobiles -- Design and construction , Motor vehicles -- Design and construction , Bolted joints
- Description: Bolted connections where used from the beginning of vehicle construction for joining two or more parts. The reliability of bolted connections is still a major problem. The objective of this research thesis is focused on an advanced monitoring system for bolted connections in vehicle construction. A mechanical “vibrating test bench”, which was developed by the aeronautical engineer Mr. Junkers, is being adapted, to suite the requirements of the automotive industry. It is designed according to DIN 65151 standards. The bolted connection is tightened to a specific torque to achieve the required preload forces and then exposed to an oscillating elastic shear force. The preload force and their loss are measured in relation to the number of load cycles. The ideal locking mechanism would be, if no settling occurs. Realistic in practice is the remaining of a sufficient preload force which doesn’t decry with time. The aim of this thesis is, to gain knowledge that will assist in the future control of the bolt locking procedure. The test bench can be used to verify the clamping capability of a bolted connection. With the dynamic computer-aided test system it will also be possible to test critical bolted joints and their safety, which reduces the probability of costly product recalls, or even severe cases of failure.
- Full Text:
- Date Issued: 2010
- Authors: Buchmann, Macro
- Date: 2010
- Subjects: Automobiles -- Design and construction , Motor vehicles -- Design and construction , Bolted joints
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9617 , http://hdl.handle.net/10948/1417 , Automobiles -- Design and construction , Motor vehicles -- Design and construction , Bolted joints
- Description: Bolted connections where used from the beginning of vehicle construction for joining two or more parts. The reliability of bolted connections is still a major problem. The objective of this research thesis is focused on an advanced monitoring system for bolted connections in vehicle construction. A mechanical “vibrating test bench”, which was developed by the aeronautical engineer Mr. Junkers, is being adapted, to suite the requirements of the automotive industry. It is designed according to DIN 65151 standards. The bolted connection is tightened to a specific torque to achieve the required preload forces and then exposed to an oscillating elastic shear force. The preload force and their loss are measured in relation to the number of load cycles. The ideal locking mechanism would be, if no settling occurs. Realistic in practice is the remaining of a sufficient preload force which doesn’t decry with time. The aim of this thesis is, to gain knowledge that will assist in the future control of the bolt locking procedure. The test bench can be used to verify the clamping capability of a bolted connection. With the dynamic computer-aided test system it will also be possible to test critical bolted joints and their safety, which reduces the probability of costly product recalls, or even severe cases of failure.
- Full Text:
- Date Issued: 2010
Evaluation of Bacillus thuringiensis Berliner as an alternative control of small hive beetles, Aethina tumida Murray (Coleoptera: Nitidulidae)
- Buchholz, S, Neumann, Peter, Neumann, K, Hepburn, H Randall
- Authors: Buchholz, S , Neumann, Peter , Neumann, K , Hepburn, H Randall
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6929 , http://hdl.handle.net/10962/d1011945
- Description: Small hive beetles, Aethina tumida Murray, are parasites and scavengers of honeybee colonies, Apis mellifera L., and have become an invasive species that can cause considerable damage in its new distribution areas. An effective subspecies of Bacillus thuringiensis Berliner (=Bt) would provide an alternative to chemical control of this pest. Therefore, we tested three different Bt strains [B. thuringiensis, var. aizawai (B401®), B. thuringiensis var. kurstaki (Novodor®) and B. thuringiensis var. San Diego tenebrionis (Jackpot®)] and Perizin® (3.2% coumaphos), each applied on combs with a pollen diet fed to pairs of adult beetles. This evaluates the products for the suppression of successful small hive beetle reproduction. While none of the tested Bt strains showed a significant effect on the number of produced wandering larvae, we could confirm the efficacy of coumaphos for the control of small hive beetles. We further show that it is also efficient when applied with a lower concentration as a liquid on the combs. We suggest the continued search for efficient Bt strains naturally infesting small hive beetles in its endemic and new ranges, which may become a part of the integrated management of this pest.
- Full Text:
- Date Issued: 2006
- Authors: Buchholz, S , Neumann, Peter , Neumann, K , Hepburn, H Randall
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6929 , http://hdl.handle.net/10962/d1011945
- Description: Small hive beetles, Aethina tumida Murray, are parasites and scavengers of honeybee colonies, Apis mellifera L., and have become an invasive species that can cause considerable damage in its new distribution areas. An effective subspecies of Bacillus thuringiensis Berliner (=Bt) would provide an alternative to chemical control of this pest. Therefore, we tested three different Bt strains [B. thuringiensis, var. aizawai (B401®), B. thuringiensis var. kurstaki (Novodor®) and B. thuringiensis var. San Diego tenebrionis (Jackpot®)] and Perizin® (3.2% coumaphos), each applied on combs with a pollen diet fed to pairs of adult beetles. This evaluates the products for the suppression of successful small hive beetle reproduction. While none of the tested Bt strains showed a significant effect on the number of produced wandering larvae, we could confirm the efficacy of coumaphos for the control of small hive beetles. We further show that it is also efficient when applied with a lower concentration as a liquid on the combs. We suggest the continued search for efficient Bt strains naturally infesting small hive beetles in its endemic and new ranges, which may become a part of the integrated management of this pest.
- Full Text:
- Date Issued: 2006
Evaluation of a 'defouling on demand' strategy for the ultrafiltration of brown water using activatable enzymes
- Authors: Buchanan, K
- Date: 1999
- Subjects: Water -- Purification , Ultrafiltration , Enzymes , Membranes (Technology)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3904 , http://hdl.handle.net/10962/d1003963 , Water -- Purification , Ultrafiltration , Enzymes , Membranes (Technology)
- Description: New approaches to the application of membranes for the production of potable water are constantly being sought after in anticipation of future demands for increasingly rigorous water quality standards and reduced environmental impact. A major limitation, however, is membrane fouling, which manifests itself as a continual reduction in flux over time and thus restricts the practical implementation to restore flux. Mechanical and chemical methods have been implemented to restore flux to ultrafiltration systems, but these either result in a break in the process operation or lead to membrane damage or additional pollution problems. This project was aimed to develop a 'defouling on demand' stategy for cleaning membranes used during brown water ultrafiltration. The process involves the use of activatable peroxidase enzymes, which were immobilised onto flat sheet polysulphone membranes. Following flux decline which reaches a critical level with the build-up of the foulant layer, the immobilised enzyme layer was activated by the addition of a chemical activator solution, in this case hydrogen peroxidase and manganous sulphate. Manganese peroxidase was found to be the most effective enzyme at alleviating fouling by degrading the foulant layer formed on the membrane surface and hence restored flux to the ultrafiltration system. A 93% flux improvement was observed when manganese peroxidase was activated when 800uM manganous sulphate, 100mM hydrogen peroxide were added in the presence of a manganese chelator, lactate. The concept and the potential benefits this system holds will be discussed in further detail.
- Full Text:
- Date Issued: 1999
- Authors: Buchanan, K
- Date: 1999
- Subjects: Water -- Purification , Ultrafiltration , Enzymes , Membranes (Technology)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3904 , http://hdl.handle.net/10962/d1003963 , Water -- Purification , Ultrafiltration , Enzymes , Membranes (Technology)
- Description: New approaches to the application of membranes for the production of potable water are constantly being sought after in anticipation of future demands for increasingly rigorous water quality standards and reduced environmental impact. A major limitation, however, is membrane fouling, which manifests itself as a continual reduction in flux over time and thus restricts the practical implementation to restore flux. Mechanical and chemical methods have been implemented to restore flux to ultrafiltration systems, but these either result in a break in the process operation or lead to membrane damage or additional pollution problems. This project was aimed to develop a 'defouling on demand' stategy for cleaning membranes used during brown water ultrafiltration. The process involves the use of activatable peroxidase enzymes, which were immobilised onto flat sheet polysulphone membranes. Following flux decline which reaches a critical level with the build-up of the foulant layer, the immobilised enzyme layer was activated by the addition of a chemical activator solution, in this case hydrogen peroxidase and manganous sulphate. Manganese peroxidase was found to be the most effective enzyme at alleviating fouling by degrading the foulant layer formed on the membrane surface and hence restored flux to the ultrafiltration system. A 93% flux improvement was observed when manganese peroxidase was activated when 800uM manganous sulphate, 100mM hydrogen peroxide were added in the presence of a manganese chelator, lactate. The concept and the potential benefits this system holds will be discussed in further detail.
- Full Text:
- Date Issued: 1999
Towards a better understanding of information systems strategy options and its link with business strategy
- Authors: Buchanan, Darryl Vaughn
- Date: 2004
- Subjects: Management information systems , Strategic planning -- Data processing , Information technology -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10864 , http://hdl.handle.net/10948/267 , Management information systems , Strategic planning -- Data processing , Information technology -- Management
- Description: There is considerable evidence that the strategic use of Information Systems can lead to a competitive advantage. There is however, a marked lack of understanding of the options available, as well as the smooth coordination of Information Systems strategy with Business strategy. This paper provides insight into the role of Information Systems and its link with business strategy. It focuses on Information Systems strategy options, and explores the criteria needed for successful Information Systems strategy and Business strategy alignment. The paper presents and examines the results of a study of strategic alignment at Volkswagen of South Africa. Data was obtained from business and Information Technology executives. The result of the study enables Volkswagen not only to benchmark themselves, but also provides direction to enable successful business/IT alignment. It identifies specific actions necessary to ensure that IT is being used to appropriately enable or drive the business strategy.
- Full Text:
- Date Issued: 2004
- Authors: Buchanan, Darryl Vaughn
- Date: 2004
- Subjects: Management information systems , Strategic planning -- Data processing , Information technology -- Management
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10864 , http://hdl.handle.net/10948/267 , Management information systems , Strategic planning -- Data processing , Information technology -- Management
- Description: There is considerable evidence that the strategic use of Information Systems can lead to a competitive advantage. There is however, a marked lack of understanding of the options available, as well as the smooth coordination of Information Systems strategy with Business strategy. This paper provides insight into the role of Information Systems and its link with business strategy. It focuses on Information Systems strategy options, and explores the criteria needed for successful Information Systems strategy and Business strategy alignment. The paper presents and examines the results of a study of strategic alignment at Volkswagen of South Africa. Data was obtained from business and Information Technology executives. The result of the study enables Volkswagen not only to benchmark themselves, but also provides direction to enable successful business/IT alignment. It identifies specific actions necessary to ensure that IT is being used to appropriately enable or drive the business strategy.
- Full Text:
- Date Issued: 2004
Teachers’ views of pragmatic strategies to enhance leadership potential for female learners in primary schools at Amathole East Education District
- Authors: Bubulu, Thandiwe
- Date: 2020-09
- Subjects: Educational leadership , School improvement programs
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/20024 , vital:44949
- Description: This study examined how the establishment of leadership development programme targeted at female learners in primary schools could promote female learner leaders and motivate more women to take up leadership positions to address concerns of gender and to prepare females for the challenges they may face when assuming leadership roles in future.Whereas adolescent girls may be the future representation of women leaders in society, leadership development of female learners in primary schools has been neglected. Currently, a review of literature on the problem of gender imbalance at leadership level reveals a dearth of research among the youth, less so, among young women. Yet, globally, in Africa and in South Africa, particularly, there is an inequitable balance of leadership positions in society when comparing men and women. The researcher has identified this gap and has decided to dedicated research efforts in adolescent leadership development to enrich the scant existing knowledge on the born-global phenomenon. Because schools play an important role in student development and schools are a key resource for achieving equity goals, understanding how leadership is promoted by school teachers is an important step toward growing the literature on female learners’ leadership development. The study was based on five primary schools in the Amathole District in the Eastern Cape Province, South Africa. The study followed a qualitative research approach where interviews were employed to elicit data from the study’s participants and to help in understanding the phenomenon under study. A non-probability, purposive sampling technique was used where ten participants were selected. The study’s participants were five (5) principals, two (2) HoDs, two (2) post level 1 teachers and one (1) Learner Support Assistant (LSA). The study found that a paradigm shift from the traditional view of leadership, where young people are not given leadership positions because they are regarded as young or quiet is a patriarchal belief system that should be done away with. Instead, role-players should embrace and encourage female children to be transformational and servant leaders. There is need for a change of mind-set from all role-players in South Africa to accept learners as equal participants in school leadership and to prioritise the training and development of female learner leaders. Female learners need to be taught a broader understanding of leadership as a concept including differing leadership theories and styles. Leadership as a concept needs to be taught early in primary school and to all learners. The study recommended leadership development seminars, camps, workshops and guest speakers that could aid in the development of leadership at primary school, and to be prioritised. The study concluded that continuous leadership training from a young age, for all learners in primary schools should be encouraged to ensure that learners chosen to lead assume leadership roles with confidence, skills and experience. Government schools need to allocate budget for leadership development of learners, with special funding for the relatively disadvantaged gender. , Thesis (DPhil) -- Faculty of Education, 2020
- Full Text:
- Date Issued: 2020-09
- Authors: Bubulu, Thandiwe
- Date: 2020-09
- Subjects: Educational leadership , School improvement programs
- Language: English
- Type: Doctoral theses , text
- Identifier: http://hdl.handle.net/10353/20024 , vital:44949
- Description: This study examined how the establishment of leadership development programme targeted at female learners in primary schools could promote female learner leaders and motivate more women to take up leadership positions to address concerns of gender and to prepare females for the challenges they may face when assuming leadership roles in future.Whereas adolescent girls may be the future representation of women leaders in society, leadership development of female learners in primary schools has been neglected. Currently, a review of literature on the problem of gender imbalance at leadership level reveals a dearth of research among the youth, less so, among young women. Yet, globally, in Africa and in South Africa, particularly, there is an inequitable balance of leadership positions in society when comparing men and women. The researcher has identified this gap and has decided to dedicated research efforts in adolescent leadership development to enrich the scant existing knowledge on the born-global phenomenon. Because schools play an important role in student development and schools are a key resource for achieving equity goals, understanding how leadership is promoted by school teachers is an important step toward growing the literature on female learners’ leadership development. The study was based on five primary schools in the Amathole District in the Eastern Cape Province, South Africa. The study followed a qualitative research approach where interviews were employed to elicit data from the study’s participants and to help in understanding the phenomenon under study. A non-probability, purposive sampling technique was used where ten participants were selected. The study’s participants were five (5) principals, two (2) HoDs, two (2) post level 1 teachers and one (1) Learner Support Assistant (LSA). The study found that a paradigm shift from the traditional view of leadership, where young people are not given leadership positions because they are regarded as young or quiet is a patriarchal belief system that should be done away with. Instead, role-players should embrace and encourage female children to be transformational and servant leaders. There is need for a change of mind-set from all role-players in South Africa to accept learners as equal participants in school leadership and to prioritise the training and development of female learner leaders. Female learners need to be taught a broader understanding of leadership as a concept including differing leadership theories and styles. Leadership as a concept needs to be taught early in primary school and to all learners. The study recommended leadership development seminars, camps, workshops and guest speakers that could aid in the development of leadership at primary school, and to be prioritised. The study concluded that continuous leadership training from a young age, for all learners in primary schools should be encouraged to ensure that learners chosen to lead assume leadership roles with confidence, skills and experience. Government schools need to allocate budget for leadership development of learners, with special funding for the relatively disadvantaged gender. , Thesis (DPhil) -- Faculty of Education, 2020
- Full Text:
- Date Issued: 2020-09
Psychofortology of adults recovering from substance-use disorders
- Authors: Bubb, Tanielle Carmen
- Date: 2011
- Subjects: Substance-related disorders -- Therapy , Substance abuse -- Treatment , Substance abuse
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9870 , http://hdl.handle.net/10948/d1008117 , Substance-related disorders -- Therapy , Substance abuse -- Treatment , Substance abuse
- Description: Evaluating the psychofortology of adults recovering from a substance-use disorder has been identified as a research priority in South Africa. This is in line with calls from researchers in diverse fields of psychology for more attention to the resilience, strengths, resources and capacities of people. This study therefore aimed to explore and describe the coping resources, sense of coherence, happiness and satisfaction with life of adults recovering from a substance-use disorder within the Nelson Mandela Metropole. The sample consisted of 99 voluntary participants from various managed recovery centres within the Nelson Mandela Metropole. Participants were given a package of questionnaires to complete under the supervision of the researcher. The assessment consisted of a biographical questionnaire and four standardized paper and pencil measures namely; the Coping Resources Inventory (CRI), the Sense of Coherence Scale (SOC-29), the Affectometer 2 (AFM-2) and the Satisfaction with Life Scale (SWLS). A quantitative, non-experimental exploratory-descriptive research method was used. Data was analysed using descriptive statistics and the Pearson product-moment correlation coefficient. Key findings include the following: Results on the CRI revealed low average mean scores on both the Coping Resources Inventory and within all the five subscales. Results of the SOC-29 revealed a high average mean score for sense of coherence. Results of the AFM-2 revealed that more positive affect than negative affect is present, resulting in happiness. Results of the SWLS revealed an average level of satisfaction with life, with most participants’ reporting neutral levels of satisfaction with life. There were significant positive correlations between the coping resources, sense of coherence, happiness and satisfaction with life of the sample. This implies that these constructs can be categorized under the subdiscipline of psychofortology. Overall, these findings emphasized the need for more research into adults recovering from a substance-use disorder.
- Full Text:
- Date Issued: 2011
- Authors: Bubb, Tanielle Carmen
- Date: 2011
- Subjects: Substance-related disorders -- Therapy , Substance abuse -- Treatment , Substance abuse
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9870 , http://hdl.handle.net/10948/d1008117 , Substance-related disorders -- Therapy , Substance abuse -- Treatment , Substance abuse
- Description: Evaluating the psychofortology of adults recovering from a substance-use disorder has been identified as a research priority in South Africa. This is in line with calls from researchers in diverse fields of psychology for more attention to the resilience, strengths, resources and capacities of people. This study therefore aimed to explore and describe the coping resources, sense of coherence, happiness and satisfaction with life of adults recovering from a substance-use disorder within the Nelson Mandela Metropole. The sample consisted of 99 voluntary participants from various managed recovery centres within the Nelson Mandela Metropole. Participants were given a package of questionnaires to complete under the supervision of the researcher. The assessment consisted of a biographical questionnaire and four standardized paper and pencil measures namely; the Coping Resources Inventory (CRI), the Sense of Coherence Scale (SOC-29), the Affectometer 2 (AFM-2) and the Satisfaction with Life Scale (SWLS). A quantitative, non-experimental exploratory-descriptive research method was used. Data was analysed using descriptive statistics and the Pearson product-moment correlation coefficient. Key findings include the following: Results on the CRI revealed low average mean scores on both the Coping Resources Inventory and within all the five subscales. Results of the SOC-29 revealed a high average mean score for sense of coherence. Results of the AFM-2 revealed that more positive affect than negative affect is present, resulting in happiness. Results of the SWLS revealed an average level of satisfaction with life, with most participants’ reporting neutral levels of satisfaction with life. There were significant positive correlations between the coping resources, sense of coherence, happiness and satisfaction with life of the sample. This implies that these constructs can be categorized under the subdiscipline of psychofortology. Overall, these findings emphasized the need for more research into adults recovering from a substance-use disorder.
- Full Text:
- Date Issued: 2011
A polarimetric method for collagenase activity measurement
- Brüning, Adrian Rudolf Nicolaus Ernst
- Authors: Brüning, Adrian Rudolf Nicolaus Ernst
- Date: 1992
- Subjects: Collagenases -- Research , Hides and skins -- Preservation -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4052 , http://hdl.handle.net/10962/d1004113 , Collagenases -- Research , Hides and skins -- Preservation -- Research
- Description: A polarimetric method for monitoring the rate of soluble collagen breakdown by collagenase enzyme action has been developed. The method represents an extension of previous physicochemical techniques based on viscometry, but is simpler and easier to carry out, particularly in the case of reaction rate studies. The method was developed arising from reports of collagenase activity measurement on inappropriate substrates such as gelatin, modified collagens and synthetic polypeptides. The optical method depends on measurement of the loss in optical rotation in solutions of soluble calfskin collagen resulting from initial enzymic cleavage of the collagen trip1e-helix, followed by spontaneous unwinding of the resultant unstable helical fragments. Specific assay conditions were chosen to ensure that the loss in optical rotation following enzymic cleavage was rapid and complete. The method is specific since in the absence of collagenase, non-specific proteinases produce only a limited decrease in solution optical activity. The method has also been compared with established physicochemical assay techniques and compares favourably with both viscometric and titrimetric collagenase assays. The availability of a rapid, sensitive and quantitative procedure for measurement of collagenase activity provides a convenient means for detecting the presence of collagenase in solution and examination of hide bacterial cultures for collagenase production. In addition, a study of biocidal compounds of potential interest in hide preservation for possible inhibitory effects on collagenase is conveniently carried out with the method. Fundamental research into synergistic action in enzymic hydrolysis of collagen is now possible, providing valuable insight into the mechanism of raw hide biodeterioration.
- Full Text:
- Date Issued: 1992
- Authors: Brüning, Adrian Rudolf Nicolaus Ernst
- Date: 1992
- Subjects: Collagenases -- Research , Hides and skins -- Preservation -- Research
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4052 , http://hdl.handle.net/10962/d1004113 , Collagenases -- Research , Hides and skins -- Preservation -- Research
- Description: A polarimetric method for monitoring the rate of soluble collagen breakdown by collagenase enzyme action has been developed. The method represents an extension of previous physicochemical techniques based on viscometry, but is simpler and easier to carry out, particularly in the case of reaction rate studies. The method was developed arising from reports of collagenase activity measurement on inappropriate substrates such as gelatin, modified collagens and synthetic polypeptides. The optical method depends on measurement of the loss in optical rotation in solutions of soluble calfskin collagen resulting from initial enzymic cleavage of the collagen trip1e-helix, followed by spontaneous unwinding of the resultant unstable helical fragments. Specific assay conditions were chosen to ensure that the loss in optical rotation following enzymic cleavage was rapid and complete. The method is specific since in the absence of collagenase, non-specific proteinases produce only a limited decrease in solution optical activity. The method has also been compared with established physicochemical assay techniques and compares favourably with both viscometric and titrimetric collagenase assays. The availability of a rapid, sensitive and quantitative procedure for measurement of collagenase activity provides a convenient means for detecting the presence of collagenase in solution and examination of hide bacterial cultures for collagenase production. In addition, a study of biocidal compounds of potential interest in hide preservation for possible inhibitory effects on collagenase is conveniently carried out with the method. Fundamental research into synergistic action in enzymic hydrolysis of collagen is now possible, providing valuable insight into the mechanism of raw hide biodeterioration.
- Full Text:
- Date Issued: 1992
The adsorption of chelating reagents on oxide minerals
- Bryson, Michael Andrew Walker
- Authors: Bryson, Michael Andrew Walker
- Date: 1986
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:20969 , http://hdl.handle.net/10962/5729
- Description: This work constitutes a fundamental study of the interaction between chelating reagents and oxide minerals . The adsorption mechanisms have been elucidated for most of the systems generated by the oxides of copper(II) or iron(III) and chelating reagents octyl hydroxamate, N-phenylbenzohydroxamate, salicylaldoxime, 5-nitrosalicylaldoxime or 8-hydroxyquinoline. The results of the preliminary work on one of the systems, viz. the oxide-hydroxamate system, indicated that the classical type adsorption process, in which the reagent forms a uniform layer of chelate over the oxide surface was not applicable. Rather, the adsorption occurred via the formation of a discrete metal-chelate precipitate at the oxide surface. In order to better understand the associated with copper (II) oxide, adsorption process the oxide was recrystallized to produce a coarser material with a more uniform surface. This allowed the oxide surface to be viewed under the scanning electron microscope and also enabled the relative concentration of "surface" and "bulk" chelate to be assessed. A detailed investigation of the effect of the system variables; pH, conditioning period, concentration, temperature, surface area and dispersing reagent on the rate of precipitation of the copper chelate species of general form, Cu(chel)2' was made. In addition the chemical nature of the adsorbed species and the structural form of the precipitates were determined with the aid of infra-red spectroscopy and the scanning electron microscope. On the basis of these results a model has been formulated for the adsorption processes. In this model the adsorption dissolution, is considered to occur in stages: 1. Oxide dissolution, 2. metal complex formation, 3. Metal chelate precipitation at the oxide surface and 4. “bulk” chelate formation by post-precipitation processes. The precipitation process was examined in more detail by the study of the adsorption of chelate on copper metal. The results of this study showed that it was possible to relate the structural type of precipitate formed, ie. fibrous or platelike, to the degree of supersaturation of the metal complex in solution. Furthermore, it was found that the precipitate structure determined whether it remained attached to the surface or detached. Contact angle measurements of air bubbles on copper metal conditioned with chelate were related to the adsorption results in an attempt to isolate the optimum conditions for flotation of oxide minerals.
- Full Text:
- Date Issued: 1986
- Authors: Bryson, Michael Andrew Walker
- Date: 1986
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:20969 , http://hdl.handle.net/10962/5729
- Description: This work constitutes a fundamental study of the interaction between chelating reagents and oxide minerals . The adsorption mechanisms have been elucidated for most of the systems generated by the oxides of copper(II) or iron(III) and chelating reagents octyl hydroxamate, N-phenylbenzohydroxamate, salicylaldoxime, 5-nitrosalicylaldoxime or 8-hydroxyquinoline. The results of the preliminary work on one of the systems, viz. the oxide-hydroxamate system, indicated that the classical type adsorption process, in which the reagent forms a uniform layer of chelate over the oxide surface was not applicable. Rather, the adsorption occurred via the formation of a discrete metal-chelate precipitate at the oxide surface. In order to better understand the associated with copper (II) oxide, adsorption process the oxide was recrystallized to produce a coarser material with a more uniform surface. This allowed the oxide surface to be viewed under the scanning electron microscope and also enabled the relative concentration of "surface" and "bulk" chelate to be assessed. A detailed investigation of the effect of the system variables; pH, conditioning period, concentration, temperature, surface area and dispersing reagent on the rate of precipitation of the copper chelate species of general form, Cu(chel)2' was made. In addition the chemical nature of the adsorbed species and the structural form of the precipitates were determined with the aid of infra-red spectroscopy and the scanning electron microscope. On the basis of these results a model has been formulated for the adsorption processes. In this model the adsorption dissolution, is considered to occur in stages: 1. Oxide dissolution, 2. metal complex formation, 3. Metal chelate precipitation at the oxide surface and 4. “bulk” chelate formation by post-precipitation processes. The precipitation process was examined in more detail by the study of the adsorption of chelate on copper metal. The results of this study showed that it was possible to relate the structural type of precipitate formed, ie. fibrous or platelike, to the degree of supersaturation of the metal complex in solution. Furthermore, it was found that the precipitate structure determined whether it remained attached to the surface or detached. Contact angle measurements of air bubbles on copper metal conditioned with chelate were related to the adsorption results in an attempt to isolate the optimum conditions for flotation of oxide minerals.
- Full Text:
- Date Issued: 1986
Separation and characterisation of chromium (III) carboxylate solutions
- Bryson, Michael Andrew Walker
- Authors: Bryson, Michael Andrew Walker
- Date: 1981
- Subjects: Chromium
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4416 , http://hdl.handle.net/10962/d1006847
- Description: From Summary: The complexes present in chromium(III) carboxylate solutions (acetate or formate) were separated using ion exchange chromatography, electrophoresis and gel filtration. Eight cationic species and one non-ionic species with charges from 0 to +3 and nuclearities ranging from mononuclear to quadranuclear were isolated from chromium(III) acetate solutions. Six cationic species with charges from +1 to +3 and nuclearities ranging from mononuclear to trinuclear were isolated from chromium(III) formate solutions. The empirical formulae for these complexes were determined by analytical methods. Infra- red spectroscopy was used to distinguish between monodentate and bidentate bridged carboxylate ligands. An immediate change in the visible spectrum of a complex on its acidification was used as evidence that a terminal hydroxo group was present.
- Full Text:
- Date Issued: 1981
- Authors: Bryson, Michael Andrew Walker
- Date: 1981
- Subjects: Chromium
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4416 , http://hdl.handle.net/10962/d1006847
- Description: From Summary: The complexes present in chromium(III) carboxylate solutions (acetate or formate) were separated using ion exchange chromatography, electrophoresis and gel filtration. Eight cationic species and one non-ionic species with charges from 0 to +3 and nuclearities ranging from mononuclear to quadranuclear were isolated from chromium(III) acetate solutions. Six cationic species with charges from +1 to +3 and nuclearities ranging from mononuclear to trinuclear were isolated from chromium(III) formate solutions. The empirical formulae for these complexes were determined by analytical methods. Infra- red spectroscopy was used to distinguish between monodentate and bidentate bridged carboxylate ligands. An immediate change in the visible spectrum of a complex on its acidification was used as evidence that a terminal hydroxo group was present.
- Full Text:
- Date Issued: 1981
An erosion and sediment delivery model for semi-arid catchments
- Authors: Bryson, Louise Kay
- Date: 2016
- Subjects: Sedimentation and deposition , Erosion , Watershed management -- South Africa , Water-supply -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6056 , http://hdl.handle.net/10962/d1020331
- Description: Sedimentation has become a significant environmental threat in South Africa as it intensifies water management problems in the water-scarce semi-arid regions of the country. As South Africa already allocates 98% of available water, the loss of storage capacity in reservoirs and degraded water quality has meant that a reliable water supply is compromised. The overall aim of this thesis was to develop a catchment scale model that represents the sediment dynamics of semi-arid regions of South Africa as a simple and practically applicable tool for water resource managers. Development of a conceptual framework for the model relied on an understanding of both the sediment dynamics of South African catchments and applicable modelling techniques. Scale was an issue in both cases as most of our understanding of the physical processes of runoff generation and sediment transport has been derived from plot scale studies. By identifying defining properties of semi-arid catchments it was possible to consider how temporal and spatial properties at higher levels emerged from properties at lower levels. These properties were effectively represented by using the Pitman rainfall-runoff model disaggregated to a daily timescale, the Modified Universal Soil Loss Equation (MUSLE) model incorporating probability function theory and through the representation of sediment storages across a semi-distributed catchment. The model was tested on two small and one large study catchment in the Karoo, South Africa, with limited observed data. Limitations to the model were found to be the large parameter data set and the dominance of structural constraints with an increase in catchment size. The next steps in model development will require a reduction of the parameter data set and an inclusion of an in-stream component for sub-catchments at a larger spatial scale. The model is applicable in areas such as South Africa where water resource managers need a simple model at the catchment scale in order to make decisions. This type of model provides a simple representation of the stochastic nature of erosion and sediment delivery over large spatial and temporal scales.
- Full Text:
- Date Issued: 2016
- Authors: Bryson, Louise Kay
- Date: 2016
- Subjects: Sedimentation and deposition , Erosion , Watershed management -- South Africa , Water-supply -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:6056 , http://hdl.handle.net/10962/d1020331
- Description: Sedimentation has become a significant environmental threat in South Africa as it intensifies water management problems in the water-scarce semi-arid regions of the country. As South Africa already allocates 98% of available water, the loss of storage capacity in reservoirs and degraded water quality has meant that a reliable water supply is compromised. The overall aim of this thesis was to develop a catchment scale model that represents the sediment dynamics of semi-arid regions of South Africa as a simple and practically applicable tool for water resource managers. Development of a conceptual framework for the model relied on an understanding of both the sediment dynamics of South African catchments and applicable modelling techniques. Scale was an issue in both cases as most of our understanding of the physical processes of runoff generation and sediment transport has been derived from plot scale studies. By identifying defining properties of semi-arid catchments it was possible to consider how temporal and spatial properties at higher levels emerged from properties at lower levels. These properties were effectively represented by using the Pitman rainfall-runoff model disaggregated to a daily timescale, the Modified Universal Soil Loss Equation (MUSLE) model incorporating probability function theory and through the representation of sediment storages across a semi-distributed catchment. The model was tested on two small and one large study catchment in the Karoo, South Africa, with limited observed data. Limitations to the model were found to be the large parameter data set and the dominance of structural constraints with an increase in catchment size. The next steps in model development will require a reduction of the parameter data set and an inclusion of an in-stream component for sub-catchments at a larger spatial scale. The model is applicable in areas such as South Africa where water resource managers need a simple model at the catchment scale in order to make decisions. This type of model provides a simple representation of the stochastic nature of erosion and sediment delivery over large spatial and temporal scales.
- Full Text:
- Date Issued: 2016
An evaluation of the potential for implementing adaptive co-management in the Waodani social-ecological system in the Ecuadorian Amazon
- Authors: Bryja, Malgorzata Anna
- Date: 2015
- Subjects: Adaptive natural resource management -- Ecuador -- Reserva de Biosfera Yasuni , Huao Indians -- Ecuador -- Reserva de Biosfera Yasuni , Natural resources -- Co-management -- Ecuador -- Reserva de Biosfera Yasuni , Social ecology -- Ecuador -- Reserva de Biosfera Yasuni , Sustainable development -- Ecuador -- Reserva de Biosfera Yasuni , Resource-based communities -- Ecuador -- Reserva de Biosfera Yasuni , Reserva de Biosfera Yasuni (Ecuador) -- Economic conditions , Huao Indians -- Ecuador -- Reserva de Biosfera Yasuni -- Economic conditions
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4784 , http://hdl.handle.net/10962/d1018192
- Description: Adaptive co-management (ACM), one of the most prominent management approaches to emerge in the recent years, combines iterative learning, flexibility, and adaptation promoted by adaptive management with the principles of nurturing diversity and fostering collaboration among different partners that underpin co-management philosophy. ACM has been proposed as an approach to address the deficiencies of centralized management in ensuring sustainability of social-ecological systems (SESs) in face of future uncertainties. This thesis aims to evaluate the readiness of resource users (the Waodani) as well as external actors (the Ecuadorian State and NGOs) for future implementation of ACM and thus enhancing the long-term social-ecological sustainability of the Waodani SES located in the Yasuni Biosphere Reserve in the Ecuadorian Amazon. Qualitative data obtained by means of focus groups with the Waodani and individual interviews with external actors and Waodani leaders revealed different levels of readiness for ACM. Firstly, in the case of the Waodani, the insufficient fulfillment of some conditions required for successful ACM as well as intercommunity differences in regards to these conditions can complicate the implementation of ACM, unless sufficient external assistance is offered to the SES. The analysis of NGOs demonstrated, on the other hand, a relative readiness for ACM, providing that such aspects as sufficient funding, long-term commitment to collaboration, and inter-institutional linkages are strengthened. The study also found that the Ecuadorian government’s potential to contribute to ACM is hindered by the lack of readiness to work with the indigenous society as well as by funding and communication challenges. Furthermore, the resource based economy supported by the State limits the scope of innovation and adaptation. Still, as in the case of other actors, overcoming the challenges and transitioning towards adaptive governance and thus ACM could be possible in the long-term, if recent legal and political changes are truly implemented.
- Full Text:
- Date Issued: 2015
- Authors: Bryja, Malgorzata Anna
- Date: 2015
- Subjects: Adaptive natural resource management -- Ecuador -- Reserva de Biosfera Yasuni , Huao Indians -- Ecuador -- Reserva de Biosfera Yasuni , Natural resources -- Co-management -- Ecuador -- Reserva de Biosfera Yasuni , Social ecology -- Ecuador -- Reserva de Biosfera Yasuni , Sustainable development -- Ecuador -- Reserva de Biosfera Yasuni , Resource-based communities -- Ecuador -- Reserva de Biosfera Yasuni , Reserva de Biosfera Yasuni (Ecuador) -- Economic conditions , Huao Indians -- Ecuador -- Reserva de Biosfera Yasuni -- Economic conditions
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4784 , http://hdl.handle.net/10962/d1018192
- Description: Adaptive co-management (ACM), one of the most prominent management approaches to emerge in the recent years, combines iterative learning, flexibility, and adaptation promoted by adaptive management with the principles of nurturing diversity and fostering collaboration among different partners that underpin co-management philosophy. ACM has been proposed as an approach to address the deficiencies of centralized management in ensuring sustainability of social-ecological systems (SESs) in face of future uncertainties. This thesis aims to evaluate the readiness of resource users (the Waodani) as well as external actors (the Ecuadorian State and NGOs) for future implementation of ACM and thus enhancing the long-term social-ecological sustainability of the Waodani SES located in the Yasuni Biosphere Reserve in the Ecuadorian Amazon. Qualitative data obtained by means of focus groups with the Waodani and individual interviews with external actors and Waodani leaders revealed different levels of readiness for ACM. Firstly, in the case of the Waodani, the insufficient fulfillment of some conditions required for successful ACM as well as intercommunity differences in regards to these conditions can complicate the implementation of ACM, unless sufficient external assistance is offered to the SES. The analysis of NGOs demonstrated, on the other hand, a relative readiness for ACM, providing that such aspects as sufficient funding, long-term commitment to collaboration, and inter-institutional linkages are strengthened. The study also found that the Ecuadorian government’s potential to contribute to ACM is hindered by the lack of readiness to work with the indigenous society as well as by funding and communication challenges. Furthermore, the resource based economy supported by the State limits the scope of innovation and adaptation. Still, as in the case of other actors, overcoming the challenges and transitioning towards adaptive governance and thus ACM could be possible in the long-term, if recent legal and political changes are truly implemented.
- Full Text:
- Date Issued: 2015
The ideals of consciousness and conduct in Henry James's The Ambassadors and The Golden Bowl
- Authors: Bryer, Lynne
- Date: 1969
- Subjects: James, Henry, 1843-1916. Ambassadors , James, Henry, 1843-1916. Golden bowl
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2321 , http://hdl.handle.net/10962/d1014635
- Description: The mature work of Henry James gives the fullest expression of certain ideals which I have called the ideals of consciousness and conduct. These ideals are the subject of this thesis. As they are best illustrated in the two novels The Ambassadors (1903) and The Golden Bowl (1904), I have first analysed these books in detail. Though emphasising "theme" rather than "techniques" (I make the usual working distinction while recognising its limitations), I have also attempted to show how intimately James's technique is related to his exploration of consciousness and conduct. In Part Three I have tried to gather up ideas arising from the analyses of The Ambassadors and The Golden Bowl to compare them, expand on them and generalise from them. In this way I have arrived at conclusions that may help to interpret mature vision of James.
- Full Text:
- Date Issued: 1969
- Authors: Bryer, Lynne
- Date: 1969
- Subjects: James, Henry, 1843-1916. Ambassadors , James, Henry, 1843-1916. Golden bowl
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2321 , http://hdl.handle.net/10962/d1014635
- Description: The mature work of Henry James gives the fullest expression of certain ideals which I have called the ideals of consciousness and conduct. These ideals are the subject of this thesis. As they are best illustrated in the two novels The Ambassadors (1903) and The Golden Bowl (1904), I have first analysed these books in detail. Though emphasising "theme" rather than "techniques" (I make the usual working distinction while recognising its limitations), I have also attempted to show how intimately James's technique is related to his exploration of consciousness and conduct. In Part Three I have tried to gather up ideas arising from the analyses of The Ambassadors and The Golden Bowl to compare them, expand on them and generalise from them. In this way I have arrived at conclusions that may help to interpret mature vision of James.
- Full Text:
- Date Issued: 1969
Shakespeare's early comedies: studies in The comedy of errors, The taming of the shrew and The two gentlemen of Verona
- Authors: Bryant, Peter
- Date: 1970
- Subjects: Shakespeare, William, 1564-1616. Comedy of Errors Shakespeare, William, 1564-1616. Comedies Shakespeare, William, 1564-1616. Two gentlemen of Verona Shakespeare, William, 1564-1616. Taming of the shrew
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2291 , http://hdl.handle.net/10962/d1009964
- Description: This dissertation offers fairly full readings of three early Shakespearean comedies. Because these works are still partly misunderstood, it has seemed reasonable to lay the critical emphasis on explication, though a certain amount of judging has been inevitable. The aim has been to induce recognition of aspects of these plays to which much modern criticism has seemed opaque.
- Full Text:
- Date Issued: 1970
- Authors: Bryant, Peter
- Date: 1970
- Subjects: Shakespeare, William, 1564-1616. Comedy of Errors Shakespeare, William, 1564-1616. Comedies Shakespeare, William, 1564-1616. Two gentlemen of Verona Shakespeare, William, 1564-1616. Taming of the shrew
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:2291 , http://hdl.handle.net/10962/d1009964
- Description: This dissertation offers fairly full readings of three early Shakespearean comedies. Because these works are still partly misunderstood, it has seemed reasonable to lay the critical emphasis on explication, though a certain amount of judging has been inevitable. The aim has been to induce recognition of aspects of these plays to which much modern criticism has seemed opaque.
- Full Text:
- Date Issued: 1970
The largest volcanic eruptions on Earth
- Bryan, Scott E, Peate, Ingrid Ukstins, Peate, David W, Self, Stephen, Jerram, Dougal A, Mawby, Michael R, Marsh, Julian S, Miller, Jodie A
- Authors: Bryan, Scott E , Peate, Ingrid Ukstins , Peate, David W , Self, Stephen , Jerram, Dougal A , Mawby, Michael R , Marsh, Julian S , Miller, Jodie A
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/132887 , vital:36902 , https://doi.org/10.1016/j.earscirev.2010.07.001
- Description: Large igneous provinces (LIPs) are sites of the most frequently recurring, largest volume basaltic and silicic eruptions in Earth history. These large-volume (> 1000 km3 dense rock equivalent) and large-magnitude (> M8) eruptions produce really extensive (104–105 km2) basaltic lava flow fields and silicic ignimbrites that are the main building blocks of LIPs.
- Full Text: false
- Date Issued: 2010
- Authors: Bryan, Scott E , Peate, Ingrid Ukstins , Peate, David W , Self, Stephen , Jerram, Dougal A , Mawby, Michael R , Marsh, Julian S , Miller, Jodie A
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/132887 , vital:36902 , https://doi.org/10.1016/j.earscirev.2010.07.001
- Description: Large igneous provinces (LIPs) are sites of the most frequently recurring, largest volume basaltic and silicic eruptions in Earth history. These large-volume (> 1000 km3 dense rock equivalent) and large-magnitude (> M8) eruptions produce really extensive (104–105 km2) basaltic lava flow fields and silicic ignimbrites that are the main building blocks of LIPs.
- Full Text: false
- Date Issued: 2010
Analysing emergent time within an isolated Universe through the application of interactions in the conditional probability approach
- Authors: Bryan, Kate Louise Halse
- Date: 2020
- Subjects: Space and time , Quantum gravity , Quantum theory , Relativity (Physics)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146676 , vital:38547
- Description: Time remains a frequently discussed issue in physics and philosophy. One interpretation of growing popularity is the ‘timeless’ view which states that our experience of time is only an illusion. The isolated Universe model, provided by the Wheeler-DeWitt equation, supports this interpretation by describing time using clocks in the conditional probability interpretation (CPI). However, the CPI customarily dismisses interaction effects as negligible creating a potential blind spot which overlooks the potential influence of interaction effects. Accounting for interactions opens up a new avenue of analysis and a potential challenge to the interpretation of time. In aid of our assessment of the impact interaction effects have on the CPI, we present rudimentary definitions of time and its associated concepts. Defined in a minimalist manner, time is argued to require a postulate of causality as a means of accounting for temporal ordering in physical theories. Several of these theories are discussed here in terms of their respective approaches to time and, despite their differences, there are indications that the accounts of time are unified in a more fundamental theory. An analytic analysis of the CPI, incorporating two different clock choices, and a qualitative analysis both confirm that interactions have a necessary role within the CPI. The consequence of removing interactions is a maximised uncertainty in any measurement of the clock and a restriction to a two-state system, as indicated by the results of the toy models and qualitative argument respectively. The philosophical implication is that we are not restricted to the timeless view since including interactions as agents of causal interventions between systems provides an account of time as a real phenomenon. This result highlights the reliance on a postulate of causality which forms a pressing problem in explaining our experience of time.
- Full Text:
- Date Issued: 2020
- Authors: Bryan, Kate Louise Halse
- Date: 2020
- Subjects: Space and time , Quantum gravity , Quantum theory , Relativity (Physics)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/146676 , vital:38547
- Description: Time remains a frequently discussed issue in physics and philosophy. One interpretation of growing popularity is the ‘timeless’ view which states that our experience of time is only an illusion. The isolated Universe model, provided by the Wheeler-DeWitt equation, supports this interpretation by describing time using clocks in the conditional probability interpretation (CPI). However, the CPI customarily dismisses interaction effects as negligible creating a potential blind spot which overlooks the potential influence of interaction effects. Accounting for interactions opens up a new avenue of analysis and a potential challenge to the interpretation of time. In aid of our assessment of the impact interaction effects have on the CPI, we present rudimentary definitions of time and its associated concepts. Defined in a minimalist manner, time is argued to require a postulate of causality as a means of accounting for temporal ordering in physical theories. Several of these theories are discussed here in terms of their respective approaches to time and, despite their differences, there are indications that the accounts of time are unified in a more fundamental theory. An analytic analysis of the CPI, incorporating two different clock choices, and a qualitative analysis both confirm that interactions have a necessary role within the CPI. The consequence of removing interactions is a maximised uncertainty in any measurement of the clock and a restriction to a two-state system, as indicated by the results of the toy models and qualitative argument respectively. The philosophical implication is that we are not restricted to the timeless view since including interactions as agents of causal interventions between systems provides an account of time as a real phenomenon. This result highlights the reliance on a postulate of causality which forms a pressing problem in explaining our experience of time.
- Full Text:
- Date Issued: 2020
The EPR paradox: back from the future
- Authors: Bryan, Kate Louise Halse
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/2881 , vital:20338
- Description: The Einstein-Podolsky-Rosen (EPR) thought experiment produced a problem regarding the interpretation of quantum mechanics provided for entangled systems. Although the thought experiment was reformulated mathematically in Bell's Theorem, the conclusion regarding entanglement correlations is still debated today. In an attempt to provide an explanation of how entangled systems maintain their correlations, this thesis investigates the theory of post-state teleportation as a possible interpretation of how information moves between entangled systems without resorting to nonlocal action. Post-state teleportation describes a method of communicating to the past via a quantum information channel. The resulting picture of the EPR thought experiment relied on information propagating backward from a final boundary condition to ensure all correlations were maintained. Similarities were found between this resolution of the EPR paradox and the final state solution to the black hole information paradox and the closely related firewall problem. The latter refers to an apparent conflict between unitary evaporation of a black hole and the strong subadditivity condition. The use of observer complementarity allows this solution of the black hole problem to be shown to be the same as a seemingly different solution known as “ER=EPR", where ‘ER’ refers to an Einstein-Rosen bridge or wormhole.
- Full Text:
- Date Issued: 2016
- Authors: Bryan, Kate Louise Halse
- Date: 2016
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/2881 , vital:20338
- Description: The Einstein-Podolsky-Rosen (EPR) thought experiment produced a problem regarding the interpretation of quantum mechanics provided for entangled systems. Although the thought experiment was reformulated mathematically in Bell's Theorem, the conclusion regarding entanglement correlations is still debated today. In an attempt to provide an explanation of how entangled systems maintain their correlations, this thesis investigates the theory of post-state teleportation as a possible interpretation of how information moves between entangled systems without resorting to nonlocal action. Post-state teleportation describes a method of communicating to the past via a quantum information channel. The resulting picture of the EPR thought experiment relied on information propagating backward from a final boundary condition to ensure all correlations were maintained. Similarities were found between this resolution of the EPR paradox and the final state solution to the black hole information paradox and the closely related firewall problem. The latter refers to an apparent conflict between unitary evaporation of a black hole and the strong subadditivity condition. The use of observer complementarity allows this solution of the black hole problem to be shown to be the same as a seemingly different solution known as “ER=EPR", where ‘ER’ refers to an Einstein-Rosen bridge or wormhole.
- Full Text:
- Date Issued: 2016
Understanding workplace bullying in SMME's of South Africa
- Authors: Bruère, Hildé
- Date: 2015
- Subjects: Bullying in the workplace -- South Africa , Business enterprises -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8844 , http://hdl.handle.net/10948/d1020092
- Description: Workplace bullying is a modern day problem which employers cannot afford to ignore. The impact on both the business (or organisation) and individual is of such a nature that research is needed to understand it better and to determine the extent to which it is present in the business or organisation. Research thus far covered the prevalence, consequences and causes of bullying in the organisation. Various methods to counteract and prevent it have been investigated, but with reference to the South African context knowledge is lacking. This study focuses on workplace bullying in SMMEs as very little research has been done in this field. The purpose of this study is to be able to provide a framework for managers as to how to deal, prevent and minimise workplace bullying in SMMEs of South Africa. A convenient sample was selected and information was gathered by means of a questionnaire. A quantitative study was executed and the prevalence of bullying in the SMMEs was established and a number of independent variables were tested. The independent variables researched were managerial training, awareness training, a corporate anti-bullying policy, risk assessment and mediation. The main findings were that bullying in SMMEs is indeed prevalent, but that the independent variables did not deliver significant correlations. The practical implications for managers are that strategies and tools used in larger organisations are not applicable in SMMEs. The workplace environment of the SMME is unique and different methods and tools must be identified and applied in combatting workplace bullying. The contribution of this study is that managers in South Africa across the broad industrial spectrum must realise that bullying is prevalent and that corporate policies and measures must be put in place to address it. It can no longer be ignored and further research on the subject must be encouraged.
- Full Text:
- Date Issued: 2015
- Authors: Bruère, Hildé
- Date: 2015
- Subjects: Bullying in the workplace -- South Africa , Business enterprises -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:8844 , http://hdl.handle.net/10948/d1020092
- Description: Workplace bullying is a modern day problem which employers cannot afford to ignore. The impact on both the business (or organisation) and individual is of such a nature that research is needed to understand it better and to determine the extent to which it is present in the business or organisation. Research thus far covered the prevalence, consequences and causes of bullying in the organisation. Various methods to counteract and prevent it have been investigated, but with reference to the South African context knowledge is lacking. This study focuses on workplace bullying in SMMEs as very little research has been done in this field. The purpose of this study is to be able to provide a framework for managers as to how to deal, prevent and minimise workplace bullying in SMMEs of South Africa. A convenient sample was selected and information was gathered by means of a questionnaire. A quantitative study was executed and the prevalence of bullying in the SMMEs was established and a number of independent variables were tested. The independent variables researched were managerial training, awareness training, a corporate anti-bullying policy, risk assessment and mediation. The main findings were that bullying in SMMEs is indeed prevalent, but that the independent variables did not deliver significant correlations. The practical implications for managers are that strategies and tools used in larger organisations are not applicable in SMMEs. The workplace environment of the SMME is unique and different methods and tools must be identified and applied in combatting workplace bullying. The contribution of this study is that managers in South Africa across the broad industrial spectrum must realise that bullying is prevalent and that corporate policies and measures must be put in place to address it. It can no longer be ignored and further research on the subject must be encouraged.
- Full Text:
- Date Issued: 2015
The impact of urban gardening on household food security: evidence from Makhanda East, Eastern Cape Province, South Africa
- Bruwer, Guillaume Marcel Xavier
- Authors: Bruwer, Guillaume Marcel Xavier
- Date: 2022-04-06
- Subjects: Food security South Africa Makhanda , Urban agriculture South Africa Makhanda , Urban gardening South Africa Makhanda , Sustainable development South Africa Makhanda , South Africa Economic conditions , Subsistence farming South Africa Makhanda , Economic impact analysis South Africa Makhanda , Propensity Score Matching (PSM)
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/263575 , vital:53640
- Description: Urban gardening in townships is a common coping strategy employed by poor inhabitants to improve food security, earn income through sales, and generate cost-savings through home consumption of fresh produce. Food security is a cornerstone of human development and welfare, and the achievement thereof remains a global challenge. The majority of academic research and policy documentation traditionally positions food insecurity as a rural phenomenon. However, recent trends point to an increase in food insecurity in urban areas, particularly in low-income areas such as townships. In South Africa, rapid urbanization has led to burgeoning townships and rapidly expanding low-income informal settlements characterised by poverty, unemployment, and food insecurity. Research concerned with the role that urban agricultural production plays in contributing to the food security of poor households is scarce and not well understood. This research, therefore, aimed to contribute to the limited research which specifically examines urban food security, and the role urban agriculture play in the achievement of household food security. The study employed collective action theory and utility theory to firstly provides an in-depth examination of the determinants of participation in urban gardening using Probit regression modeling. The second research objective was to perform an impact evaluation of participation in urban gardening on selected household food security indicators including Household Dietary Diversity Scores (HDDS), the Household Hunger Scale (HHS) and the Coping Strategy Index (CSI) using Propensity Score Matching (PSM). Purposive and snowball sampling methods were employed to obtain a sample of 60 urban gardeners and a control group of 55 non-gardening households from Extension 6, 7 and 10 townships as well as Joza Location in Makhanda East, Eastern Cape Province. Households were surveyed using a structured household food security questionnaire. A focus group discussion was held with the Linomtha Community Garden members and key informant interviews were undertaken with important stakeholders such as the local extension officers. Descriptive analysis revealed that urban gardening households (UGs) had older household heads who were less educated, and that land and water availability were the dominant constraints to increases in agricultural production. Results from the probit and average marginal effects models showed that the likelihood of participation significantly increased when household unemployment and dependency increased and that households who were engaged in off-farm economic activity were more likely to participate in urban gardening. The impact evaluation was performed using PSM and Average Treatment Effect on the Treated (ATT). Analysis illustrated that participation in urban gardening does significantly reduce both the full CSI and Reduced CSI. Thus, participation in urban gardening improves the food security of participating households by significantly reducing the frequency of participating households (UGs) applying undesirable coping strategies such as sending children elsewhere other than the household, borrowing food from other households and reducing the number of meals eaten in a day due to food shortages. This study posits that urban gardening alone will not eradicate the rampant food insecurity and poverty which pervades in South Africa’s townships. However, urban gardening participation does contribute to the construction of a sustainable, urban livelihood by reducing the number and severity of the undesirable coping strategies that food insecure households employ by providing some nutritious produce as well improved social capital through gardening networks and supporting institutions. It is recommended that policy makers, at a national and municipal level, need to create a clearer directive for the integration of urban food production into the urban food marketplace thus increasing access to income generating channels for small-scale home, and community gardeners. Co-operation between private and public institutions for food security and urban gardeners needs to be fostered and awareness of opportunities to participate in urban gardens needs to be improved. Central to the developmental challenges that rapid increases in urbanization and food insecurity in poor urban areas, is the need for national and local governments to improve access to economic opportunities in township areas - both in urban agriculture and in other, skills intensive sectors. , Thesis (MEcon) -- Faculty of Commerce, Economics and Economic History, 2022
- Full Text:
- Date Issued: 2022-04-06
- Authors: Bruwer, Guillaume Marcel Xavier
- Date: 2022-04-06
- Subjects: Food security South Africa Makhanda , Urban agriculture South Africa Makhanda , Urban gardening South Africa Makhanda , Sustainable development South Africa Makhanda , South Africa Economic conditions , Subsistence farming South Africa Makhanda , Economic impact analysis South Africa Makhanda , Propensity Score Matching (PSM)
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/263575 , vital:53640
- Description: Urban gardening in townships is a common coping strategy employed by poor inhabitants to improve food security, earn income through sales, and generate cost-savings through home consumption of fresh produce. Food security is a cornerstone of human development and welfare, and the achievement thereof remains a global challenge. The majority of academic research and policy documentation traditionally positions food insecurity as a rural phenomenon. However, recent trends point to an increase in food insecurity in urban areas, particularly in low-income areas such as townships. In South Africa, rapid urbanization has led to burgeoning townships and rapidly expanding low-income informal settlements characterised by poverty, unemployment, and food insecurity. Research concerned with the role that urban agricultural production plays in contributing to the food security of poor households is scarce and not well understood. This research, therefore, aimed to contribute to the limited research which specifically examines urban food security, and the role urban agriculture play in the achievement of household food security. The study employed collective action theory and utility theory to firstly provides an in-depth examination of the determinants of participation in urban gardening using Probit regression modeling. The second research objective was to perform an impact evaluation of participation in urban gardening on selected household food security indicators including Household Dietary Diversity Scores (HDDS), the Household Hunger Scale (HHS) and the Coping Strategy Index (CSI) using Propensity Score Matching (PSM). Purposive and snowball sampling methods were employed to obtain a sample of 60 urban gardeners and a control group of 55 non-gardening households from Extension 6, 7 and 10 townships as well as Joza Location in Makhanda East, Eastern Cape Province. Households were surveyed using a structured household food security questionnaire. A focus group discussion was held with the Linomtha Community Garden members and key informant interviews were undertaken with important stakeholders such as the local extension officers. Descriptive analysis revealed that urban gardening households (UGs) had older household heads who were less educated, and that land and water availability were the dominant constraints to increases in agricultural production. Results from the probit and average marginal effects models showed that the likelihood of participation significantly increased when household unemployment and dependency increased and that households who were engaged in off-farm economic activity were more likely to participate in urban gardening. The impact evaluation was performed using PSM and Average Treatment Effect on the Treated (ATT). Analysis illustrated that participation in urban gardening does significantly reduce both the full CSI and Reduced CSI. Thus, participation in urban gardening improves the food security of participating households by significantly reducing the frequency of participating households (UGs) applying undesirable coping strategies such as sending children elsewhere other than the household, borrowing food from other households and reducing the number of meals eaten in a day due to food shortages. This study posits that urban gardening alone will not eradicate the rampant food insecurity and poverty which pervades in South Africa’s townships. However, urban gardening participation does contribute to the construction of a sustainable, urban livelihood by reducing the number and severity of the undesirable coping strategies that food insecure households employ by providing some nutritious produce as well improved social capital through gardening networks and supporting institutions. It is recommended that policy makers, at a national and municipal level, need to create a clearer directive for the integration of urban food production into the urban food marketplace thus increasing access to income generating channels for small-scale home, and community gardeners. Co-operation between private and public institutions for food security and urban gardeners needs to be fostered and awareness of opportunities to participate in urban gardens needs to be improved. Central to the developmental challenges that rapid increases in urbanization and food insecurity in poor urban areas, is the need for national and local governments to improve access to economic opportunities in township areas - both in urban agriculture and in other, skills intensive sectors. , Thesis (MEcon) -- Faculty of Commerce, Economics and Economic History, 2022
- Full Text:
- Date Issued: 2022-04-06
Subtropical Fruits: AGH 422
- Authors: Brutsch, M O , Soundy, P
- Date: 2010-02
- Subjects: Horticulture
- Language: English
- Type: Examination paper
- Identifier: vital:17570 , http://hdl.handle.net/10353/d1009915
- Description: Subtropical Fruits: AGH 422, supplementary examination February 2010.
- Full Text: false
- Date Issued: 2010-02
- Authors: Brutsch, M O , Soundy, P
- Date: 2010-02
- Subjects: Horticulture
- Language: English
- Type: Examination paper
- Identifier: vital:17570 , http://hdl.handle.net/10353/d1009915
- Description: Subtropical Fruits: AGH 422, supplementary examination February 2010.
- Full Text: false
- Date Issued: 2010-02
Advanced Studies in the Field of the Student's Research Project (Horticultural Science): AGH 604
- Authors: Brutsch, M O , Soundy, P
- Date: 2009-11
- Language: English
- Type: Examination paper
- Identifier: vital:17584 , http://hdl.handle.net/10353/d1009931
- Description: Advanced Studies in the Field of the Student's Research Project (Horticultural Science): AGH 604, degree examination November 2009.
- Full Text: false
- Date Issued: 2009-11
- Authors: Brutsch, M O , Soundy, P
- Date: 2009-11
- Language: English
- Type: Examination paper
- Identifier: vital:17584 , http://hdl.handle.net/10353/d1009931
- Description: Advanced Studies in the Field of the Student's Research Project (Horticultural Science): AGH 604, degree examination November 2009.
- Full Text: false
- Date Issued: 2009-11