Decryption of Wire-level Network Protocols for Forensic Inspection
- Authors: Irwin, Barry V W
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428339 , vital:72504 , https://www.researchgate.net/profile/Barry-Irwin/publication/327622612_Decryption_of_Wire-lev-el_Network_Protocols_for_Forensic_Inspection/links/5b9a1220299bf14ad4d6a3b1/Decryption-of-Wire-level-Network-Protocols-for-Forensic-Inspection.pdf
- Description: With the increased use of encrypted transport protocols, the problem of debugging and monitoring the contents of these protocols has in-creased in complexity. This work proposes the development of a unified means of access to the plaintext, through the use of privileged access to the encryption keys, based on the assumption that an administrator has legitimate access to one side of a communication, and is thereby able to gain access to the encryption tokens.
- Full Text:
- Date Issued: 2004
- Authors: Irwin, Barry V W
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428339 , vital:72504 , https://www.researchgate.net/profile/Barry-Irwin/publication/327622612_Decryption_of_Wire-lev-el_Network_Protocols_for_Forensic_Inspection/links/5b9a1220299bf14ad4d6a3b1/Decryption-of-Wire-level-Network-Protocols-for-Forensic-Inspection.pdf
- Description: With the increased use of encrypted transport protocols, the problem of debugging and monitoring the contents of these protocols has in-creased in complexity. This work proposes the development of a unified means of access to the plaintext, through the use of privileged access to the encryption keys, based on the assumption that an administrator has legitimate access to one side of a communication, and is thereby able to gain access to the encryption tokens.
- Full Text:
- Date Issued: 2004
Design and evaluation of a new pharmaceutical pictogram sequence to convey medicine usage
- Mansoor, Leila E, Dowse, Roslind
- Authors: Mansoor, Leila E , Dowse, Roslind
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6402 , http://hdl.handle.net/10962/d1006338
- Description: Pictorials may be used to augment textual instructions in the depiction of safety and warning information on medicines. The objective of this study was to design, develop and evaluate a simple and culturally appropriate pictogram sequence for using nystatin suspension, and to assess its understandability in low-literate Xhosa participants. A new pharmaceutical pictogram sequence was designed through focus group discussions and evaluated in a 2-phase process. The results of Phase 1 (30 participants) identified various problems associated with the new pictogram sequence. It was modified accordingly and re-evaluated in Phase 2 with 20 participants. All participants belonged to the Xhosa group, had between 0 and 7 years of formal schooling and had English as their second language. Acceptance of the new pictogram sequence was based on international standards (ANSI and ISO criterion) for evaluating the comprehensibility of pictograms. In Phase 1, the new pictogram sequence was correctly interpreted by 66.7% of the participants and this complied with the ISO criterion of 67% correct. In Phase 2, 95% of the participants were able to correctly interpret the new pictogram sequence. This result complied with the ANSI criterion of 85% correct, therefore, this new pictogram sequence was considered to be acceptable. This study has illustrated the success of using a consultative approach in the design of new pictograms.
- Full Text:
- Date Issued: 2004
- Authors: Mansoor, Leila E , Dowse, Roslind
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6402 , http://hdl.handle.net/10962/d1006338
- Description: Pictorials may be used to augment textual instructions in the depiction of safety and warning information on medicines. The objective of this study was to design, develop and evaluate a simple and culturally appropriate pictogram sequence for using nystatin suspension, and to assess its understandability in low-literate Xhosa participants. A new pharmaceutical pictogram sequence was designed through focus group discussions and evaluated in a 2-phase process. The results of Phase 1 (30 participants) identified various problems associated with the new pictogram sequence. It was modified accordingly and re-evaluated in Phase 2 with 20 participants. All participants belonged to the Xhosa group, had between 0 and 7 years of formal schooling and had English as their second language. Acceptance of the new pictogram sequence was based on international standards (ANSI and ISO criterion) for evaluating the comprehensibility of pictograms. In Phase 1, the new pictogram sequence was correctly interpreted by 66.7% of the participants and this complied with the ISO criterion of 67% correct. In Phase 2, 95% of the participants were able to correctly interpret the new pictogram sequence. This result complied with the ANSI criterion of 85% correct, therefore, this new pictogram sequence was considered to be acceptable. This study has illustrated the success of using a consultative approach in the design of new pictograms.
- Full Text:
- Date Issued: 2004
Design and implementation of robotic control for industrial applications
- Authors: Will, Desmond Jeffrey
- Date: 2004
- Subjects: Robotics
- Language: English
- Type: Thesis , Masters , MTech (Electrical Engineering)
- Identifier: vital:10819 , http://hdl.handle.net/10948/213 , Robotics
- Description: Background: With the pressing need for increased productivity and delivery of end products of uniform quality, industry is turning more and more to computer-based automation. At the present time, most of industrial automated manufacturing is carried out by specialpurpose machines, designed to perform specific functions in a manufacturing process. The inflexibility and generally high cost of these machines often referred to as hard automation systems, have led to a broad-based interest in the use of robots capable of performing a variety of manufacturing functions in a more flexible working environment and at lower production costs. A robot is a reprogrammable general-purpose manipulator with external sensors that can perform various assembly tasks. A robot may possess intelligence, which is normally due to computer algorithms associated with its controls and sensing systems. Industrial robots are general-purpose, computer-controlled manipulators consisting of several rigid links connected in series by revolute or prismatic joints. Most of today’s industrial robots, though controlled by mini and microcomputers are basically simple positional machines. They execute a given task by playing back a prerecorded or preprogrammed sequence of motion that has been previously guided or taught by the hand-held control teach box. Moreover, these robots are equipped with little or no external sensors for obtaining the information vital to its working environment. As a result robots are used mainly for relatively simple, repetitive tasks. More research effort has been directed in sensory feedback systems, which has resulted in improving the overall performance of the manipulator system. An example of a sensory feedback system would be: a vision Charge-Coupled Device (CCD) system. This can be utilized to manipulate the robot position dependant on the surrounding robot environment (various object profile sizes). This vision system can only be used within the robot movement envelope
- Full Text:
- Date Issued: 2004
- Authors: Will, Desmond Jeffrey
- Date: 2004
- Subjects: Robotics
- Language: English
- Type: Thesis , Masters , MTech (Electrical Engineering)
- Identifier: vital:10819 , http://hdl.handle.net/10948/213 , Robotics
- Description: Background: With the pressing need for increased productivity and delivery of end products of uniform quality, industry is turning more and more to computer-based automation. At the present time, most of industrial automated manufacturing is carried out by specialpurpose machines, designed to perform specific functions in a manufacturing process. The inflexibility and generally high cost of these machines often referred to as hard automation systems, have led to a broad-based interest in the use of robots capable of performing a variety of manufacturing functions in a more flexible working environment and at lower production costs. A robot is a reprogrammable general-purpose manipulator with external sensors that can perform various assembly tasks. A robot may possess intelligence, which is normally due to computer algorithms associated with its controls and sensing systems. Industrial robots are general-purpose, computer-controlled manipulators consisting of several rigid links connected in series by revolute or prismatic joints. Most of today’s industrial robots, though controlled by mini and microcomputers are basically simple positional machines. They execute a given task by playing back a prerecorded or preprogrammed sequence of motion that has been previously guided or taught by the hand-held control teach box. Moreover, these robots are equipped with little or no external sensors for obtaining the information vital to its working environment. As a result robots are used mainly for relatively simple, repetitive tasks. More research effort has been directed in sensory feedback systems, which has resulted in improving the overall performance of the manipulator system. An example of a sensory feedback system would be: a vision Charge-Coupled Device (CCD) system. This can be utilized to manipulate the robot position dependant on the surrounding robot environment (various object profile sizes). This vision system can only be used within the robot movement envelope
- Full Text:
- Date Issued: 2004
Design of a performance evaluation tool for multimedia databases with special reference to Oracle
- Authors: Stakemire, Tonia
- Date: 2004
- Subjects: Oracle (Computer file) , Application software -- Evaluation , Database management -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4705 , http://hdl.handle.net/10962/d1015975
- Description: Increased production and use of multimedia data has led to the development of a more advanced Database Management System (DBMS), like an Object Relational Database Management System (ORDBMS). These advanced databases are necessitated by the complexity in structure and the functionality required by multimedia data. Unfortunately, no suitable benchmarks exist with which to test the performance of databases when handling multimedia data. This thesis describes the design of a benchmark to measure the performance of basic functionality found in multimedia databases. The benchmark, called MORD (Multimedia Object Relational Databases), targets Oracle, a well known commercial Object Relational Database Management System (ORDBMS) that can handle multimedia data. Although MORD targets Oracle, it can easily be applied to other Multimedia Database Management System (MMDBMS) as a result of a design that stressed its portability, and simplicity. MORD consists of a database schema, test data, and code to simulate representative queries on multimedia databases. A number of experiments are described that validate MORD and ensure its correct design and that its objectives are met. A by-product of these experiments is an initial understanding of the performance of multimedia databases. The experiments show that with multimedia data the buffer cache should be at least large enough to hold the largest dataset, a bigger block size improves the performance, and turning off logging and caching for bulk loading improves the performance. MORD can be used to compare different ORDBMS or to assist in the configuration of a specific database.
- Full Text:
- Date Issued: 2004
- Authors: Stakemire, Tonia
- Date: 2004
- Subjects: Oracle (Computer file) , Application software -- Evaluation , Database management -- Evaluation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4705 , http://hdl.handle.net/10962/d1015975
- Description: Increased production and use of multimedia data has led to the development of a more advanced Database Management System (DBMS), like an Object Relational Database Management System (ORDBMS). These advanced databases are necessitated by the complexity in structure and the functionality required by multimedia data. Unfortunately, no suitable benchmarks exist with which to test the performance of databases when handling multimedia data. This thesis describes the design of a benchmark to measure the performance of basic functionality found in multimedia databases. The benchmark, called MORD (Multimedia Object Relational Databases), targets Oracle, a well known commercial Object Relational Database Management System (ORDBMS) that can handle multimedia data. Although MORD targets Oracle, it can easily be applied to other Multimedia Database Management System (MMDBMS) as a result of a design that stressed its portability, and simplicity. MORD consists of a database schema, test data, and code to simulate representative queries on multimedia databases. A number of experiments are described that validate MORD and ensure its correct design and that its objectives are met. A by-product of these experiments is an initial understanding of the performance of multimedia databases. The experiments show that with multimedia data the buffer cache should be at least large enough to hold the largest dataset, a bigger block size improves the performance, and turning off logging and caching for bulk loading improves the performance. MORD can be used to compare different ORDBMS or to assist in the configuration of a specific database.
- Full Text:
- Date Issued: 2004
Designing an evaluation instrument for South African intermediate phase school textbooks
- Authors: Vosloo, Barend Jacobus
- Date: 2004
- Subjects: Textbooks -- South Africa -- Evaluation , Curriculum change -- South Africa -- Evaluation
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:11014 , http://hdl.handle.net/10948/324 , Textbooks -- South Africa -- Evaluation , Curriculum change -- South Africa -- Evaluation
- Description: No coherent theory about the practice of South African intermediate phase school textbook evaluation has been forthcoming since the advent of a new South African school curriculum in 1998. This deficiency has had an adverse effect on the quality of intermediate phase school textbooks, as well as on the capacity to assess their value. This research project, therefore, had two aims. The first was to articulate a theory about the practice of textbook evaluation. The second was to develop a procedure for evaluating South African intermediate phase school textbooks in terms of the theory. The research method was underpinned by the interpretive research paradigm in terms of which relevant data were analysed and interpreted. The data emanated from a literature review, an analysis of the national Department of Education’s Revised National Curriculum Statement and its draft policy for the evaluation of learning support material, and two surveys. The first survey comprised a sample of intermediate phase teachers and the second a sample of intermediate phase textbook authors. Sufficient evidence was found to conclude that the capabilities of the authoring team, the authors’ rationale and their observance of the process of learning and instruction, the accessibility of the textbook, the availability of teacher support, meeting the requirements of the Revised National Curriculum Statement, and certain key notions about textbook evaluation play a role in articulating a theory about textbook evaluation in order to guide the process of determining the effectiveness of South African intermediate phase school textbooks. Based on the above-mentioned theory, this study proposes a procedure to assist teachers and textbook evaluators to assess the worth of South African intermediate phase school textbooks in a brief, systematic, thorough, rigorous, and practical manner.
- Full Text:
- Date Issued: 2004
- Authors: Vosloo, Barend Jacobus
- Date: 2004
- Subjects: Textbooks -- South Africa -- Evaluation , Curriculum change -- South Africa -- Evaluation
- Language: English
- Type: Thesis , Doctoral , DEd
- Identifier: vital:11014 , http://hdl.handle.net/10948/324 , Textbooks -- South Africa -- Evaluation , Curriculum change -- South Africa -- Evaluation
- Description: No coherent theory about the practice of South African intermediate phase school textbook evaluation has been forthcoming since the advent of a new South African school curriculum in 1998. This deficiency has had an adverse effect on the quality of intermediate phase school textbooks, as well as on the capacity to assess their value. This research project, therefore, had two aims. The first was to articulate a theory about the practice of textbook evaluation. The second was to develop a procedure for evaluating South African intermediate phase school textbooks in terms of the theory. The research method was underpinned by the interpretive research paradigm in terms of which relevant data were analysed and interpreted. The data emanated from a literature review, an analysis of the national Department of Education’s Revised National Curriculum Statement and its draft policy for the evaluation of learning support material, and two surveys. The first survey comprised a sample of intermediate phase teachers and the second a sample of intermediate phase textbook authors. Sufficient evidence was found to conclude that the capabilities of the authoring team, the authors’ rationale and their observance of the process of learning and instruction, the accessibility of the textbook, the availability of teacher support, meeting the requirements of the Revised National Curriculum Statement, and certain key notions about textbook evaluation play a role in articulating a theory about textbook evaluation in order to guide the process of determining the effectiveness of South African intermediate phase school textbooks. Based on the above-mentioned theory, this study proposes a procedure to assist teachers and textbook evaluators to assess the worth of South African intermediate phase school textbooks in a brief, systematic, thorough, rigorous, and practical manner.
- Full Text:
- Date Issued: 2004
Determination of 2′, 3′-Dideoxyinosine Using Iron (II) Phthalocyanine Modified Carbon Paste Electrode
- Ozoemena, Kenneth I, Stefan, Raluca-Ioana, Nyokong, Tebello
- Authors: Ozoemena, Kenneth I , Stefan, Raluca-Ioana , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300298 , vital:57914 , xlink:href="https://doi.org/10.1081/AL-200031940"
- Description: An amperometric sensor, based on carbon paste impregnated with iron (II) phthalocyanine complex (FePc), has been constructed for the assay of anti‐HIV agent dideoxyinosine (didanosine, DDI). Using chronoamperometry (E = +1.04 V versus Ag/AgCl) technique, the amperometric sensor can be used reliably for dideoxyinosine assay at pH 7.4 phosphate buffer in the 1.5–9.5 nmol/L concentration range with a detection limit of 5.7 × 10−10 mol/L. The surface of the electrode can easily be regenerated by simple polishing, obtaining a fresh surface ready for use in a new assay. The new amperometric sensor proved to be highly reliable for the assay of dideoxyinosine purity in raw material as well as for the uniformity content test of Videx® tablets.
- Full Text:
- Date Issued: 2004
- Authors: Ozoemena, Kenneth I , Stefan, Raluca-Ioana , Nyokong, Tebello
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/300298 , vital:57914 , xlink:href="https://doi.org/10.1081/AL-200031940"
- Description: An amperometric sensor, based on carbon paste impregnated with iron (II) phthalocyanine complex (FePc), has been constructed for the assay of anti‐HIV agent dideoxyinosine (didanosine, DDI). Using chronoamperometry (E = +1.04 V versus Ag/AgCl) technique, the amperometric sensor can be used reliably for dideoxyinosine assay at pH 7.4 phosphate buffer in the 1.5–9.5 nmol/L concentration range with a detection limit of 5.7 × 10−10 mol/L. The surface of the electrode can easily be regenerated by simple polishing, obtaining a fresh surface ready for use in a new assay. The new amperometric sensor proved to be highly reliable for the assay of dideoxyinosine purity in raw material as well as for the uniformity content test of Videx® tablets.
- Full Text:
- Date Issued: 2004
Determining the elements of the operations management transformation model for the monitoring and breaching of the Great Brak River Mouth system
- Authors: Kriel, J F
- Date: 2004
- Subjects: Rivers -- Management -- South Africa , Stream conservation -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10935 , http://hdl.handle.net/10948/214 , Rivers -- Management -- South Africa , Stream conservation -- South Africa
- Description: The prime challenge to those responsible for the management of South Africa’s estuaries is to maintain their viability in the face of ever increasing pressures. It is important that we learn to appreciate the value of estuaries and that we act wisely to manage them for sustainable use. Any operation must have the adequate resources to perform the duties and the correct processes must be followed. The purpose of this research is to determine whether the current inputs and processes needed for the monitoring and breaching of the Great Brak River Mouth system are sufficient to adhere to the output objectives of a healthy estuary together with safeguarding of properties. The research methodology for this study comprised the following steps: Firstly, a literature study was performed to identify the key elements of the operation management transformation model. Operations management deals with the output of any business, in other words the conversion of inputs to create certain outputs and they do this by a process of transformation. Secondly, extensive literature study was performed in order to access material regarding effective estuary and river mouth management. Thirdly, the current situation at Great Brak was assessed to determine whether the current inputs and processes are in place and if additional or altered inputs and processes are needed.
- Full Text:
- Date Issued: 2004
- Authors: Kriel, J F
- Date: 2004
- Subjects: Rivers -- Management -- South Africa , Stream conservation -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10935 , http://hdl.handle.net/10948/214 , Rivers -- Management -- South Africa , Stream conservation -- South Africa
- Description: The prime challenge to those responsible for the management of South Africa’s estuaries is to maintain their viability in the face of ever increasing pressures. It is important that we learn to appreciate the value of estuaries and that we act wisely to manage them for sustainable use. Any operation must have the adequate resources to perform the duties and the correct processes must be followed. The purpose of this research is to determine whether the current inputs and processes needed for the monitoring and breaching of the Great Brak River Mouth system are sufficient to adhere to the output objectives of a healthy estuary together with safeguarding of properties. The research methodology for this study comprised the following steps: Firstly, a literature study was performed to identify the key elements of the operation management transformation model. Operations management deals with the output of any business, in other words the conversion of inputs to create certain outputs and they do this by a process of transformation. Secondly, extensive literature study was performed in order to access material regarding effective estuary and river mouth management. Thirdly, the current situation at Great Brak was assessed to determine whether the current inputs and processes are in place and if additional or altered inputs and processes are needed.
- Full Text:
- Date Issued: 2004
Developing evidence-based practice: the role of case-based research
- Edwards, David J A, Dattilio, F M, Bromley, D B
- Authors: Edwards, David J A , Dattilio, F M , Bromley, D B
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6243 , http://hdl.handle.net/10962/d1007856
- Description: How can practitioners engage in evidence-based practice when the evidence for effectiveness of psychological treatments comes from randomized controlled trials using patient populations different from those encountered in everyday settings and treatment manuals that seem oversimplified and inflexible? The authors argue that important evidence about best practice comes from case-based research, which builds knowledge in a clinically useful manner and complements what is achieved by multivariate research methods. A multidimensional model of the research process is provided that includes clinical practice and case-based research as significant contributors. The authors summarize the principles of case-based research and provide examples of recent technical advances. Finally, the authors suggest ways in which practitioners can apply the case-based approach in researching and publishing their own cases, perhaps in collaboration with university-based researchers.
- Full Text:
- Date Issued: 2004
- Authors: Edwards, David J A , Dattilio, F M , Bromley, D B
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6243 , http://hdl.handle.net/10962/d1007856
- Description: How can practitioners engage in evidence-based practice when the evidence for effectiveness of psychological treatments comes from randomized controlled trials using patient populations different from those encountered in everyday settings and treatment manuals that seem oversimplified and inflexible? The authors argue that important evidence about best practice comes from case-based research, which builds knowledge in a clinically useful manner and complements what is achieved by multivariate research methods. A multidimensional model of the research process is provided that includes clinical practice and case-based research as significant contributors. The authors summarize the principles of case-based research and provide examples of recent technical advances. Finally, the authors suggest ways in which practitioners can apply the case-based approach in researching and publishing their own cases, perhaps in collaboration with university-based researchers.
- Full Text:
- Date Issued: 2004
Developing risk management strategies for stock market investment portfolio management
- Authors: Grant, Peter
- Date: 2004
- Subjects: Stocks , Risk management , Portfolio management , Investments , Securities
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10936 , http://hdl.handle.net/10948/215 , Stocks , Risk management , Portfolio management , Investments , Securities
- Description: This study was conducted to establish whether risk management strategies could be developed to enable stock market investment portfolio managers to reduce the risk involved in stock market trading. The awareness of stock market risk elevates the requirement for risk management strategies as discussed in Chapter 1. The research scope is identified, and an overview of the study gives further guidance as to what lies ahead. The theory behind macroeconomic forces and how they influence share prices is discussed in Chapter 2. It is established that market sectors and companies within those sectors react differently to macroeconomic forces. Technical analysis is discussed as a mechanism to identify buying and selling signals. In Chapter 3, risk management strategies are developed from the literature. The hypothesis of the study as described in Chapter 4 is that these risk management strategies are able to reduce the risk associated with trading in the stock market. The market simulation in Chapter 5 offers the opportunity to observe the risk management strategies at work in a simulated stock market investment portfolio. In Chapter 6, the outcome of the market simulation is compared to the criteria set in Chapter 4, and the conclusion that the risk management strategies were able to reduce the risk involved in stock market trading is drawn.
- Full Text:
- Date Issued: 2004
- Authors: Grant, Peter
- Date: 2004
- Subjects: Stocks , Risk management , Portfolio management , Investments , Securities
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: vital:10936 , http://hdl.handle.net/10948/215 , Stocks , Risk management , Portfolio management , Investments , Securities
- Description: This study was conducted to establish whether risk management strategies could be developed to enable stock market investment portfolio managers to reduce the risk involved in stock market trading. The awareness of stock market risk elevates the requirement for risk management strategies as discussed in Chapter 1. The research scope is identified, and an overview of the study gives further guidance as to what lies ahead. The theory behind macroeconomic forces and how they influence share prices is discussed in Chapter 2. It is established that market sectors and companies within those sectors react differently to macroeconomic forces. Technical analysis is discussed as a mechanism to identify buying and selling signals. In Chapter 3, risk management strategies are developed from the literature. The hypothesis of the study as described in Chapter 4 is that these risk management strategies are able to reduce the risk associated with trading in the stock market. The market simulation in Chapter 5 offers the opportunity to observe the risk management strategies at work in a simulated stock market investment portfolio. In Chapter 6, the outcome of the market simulation is compared to the criteria set in Chapter 4, and the conclusion that the risk management strategies were able to reduce the risk involved in stock market trading is drawn.
- Full Text:
- Date Issued: 2004
Development of a hydantoin-hydrolysing biocatalyst for the production of optically pure amino acids using Agrobacterium tumefaciens strain RU-ORPN1
- Authors: Foster, Ingrid Margaret
- Date: 2004
- Subjects: Agrobacterium tumefaciens Amino acids Hydantoin Hydrolysis Enzymes
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3943 , http://hdl.handle.net/10962/d1004002
- Description: A calcium alginate bead-immobilised biocatalyst was developed utilising the D-hydantoinase and D-N-carbamoylase from a novel, mutant Agrobacterium tumefaciens strain RU-ORPN1. The growth conditions for the inducer-independent strain were optimised for production of hydantoinase and N-carbamoylase activities. Methods for the preparation of crude enzyme extracts were evaluated in terms of hydantoinase and N-carbamoylase activities produced. After comparison of the enzyme activities and stabilities in various extracts from fresh and frozen cells, sonication of frozen cells for 5 minutes was found to be the best method for the production of the enzyme extract. The optimal pH and temperature for the hydantoinase activity were pH 10 and 30°C, respectively, while pH 9 and 40°C were optimal for Ncarbamoylase activity. The hydantoinase activity was enhanced by the addition of Mg^(2+) ions to the enzyme extract and the N-carbamoylase was enhanced by the addition of Mg^(2+), Mn^(2+) or Zn^(2+) ions to the enzyme extract. The enzyme activities increased in the presence of ATP suggesting that the enzymes may be ATP-dependent. The addition of DTT and PMSF to the enzyme extract enhanced the hydantoinase activity but had no effect on the N-carbamoylase activity. The N-carbamoylase was unstable at 40°C and was almost completely inactivated after 24 hours incubation at this temperature. The hydantoinase and N-carbamoylase appeared to be insoluble. Various techniques were investigated for the solubilisation of the enzymes including various cell lysis methods, cell lysis at extremes of pH and ionic strength, addition of a reducing agent and protease inhibitors, and treatment with hydrolysing enzymes and detergents. Treatment with Triton X-100 was most effective for the solubilisation of the enzymes indicating that the enzymes were membrane-bound. Hydropathy and transmembrane prediction plots of the predicted amino acid sequences for two identified N-carbamoylase genes from A. tumefaciens RU-ORPN1 revealed possible transmembrane regions in the amino acid sequences, and thus supported the hypothesis that the enzymes were membrane-bound. Various methods were evaluated for the immobilisation of the enzymes in whole cells and enzyme extracts. Immobilisation of the enzyme extract in calcium alginate beads was found to be the best method in terms of enzyme activity retention and stability. The hydantoinase retained 55% activity while the N-carbamoylase exhibited a remarkable sevenfold increase in activity after immobilisation by this method. Furthermore, the hydantoinase activity increased after storage at 4°C for 21 days, while the N-carbamoylase retained 30% activity after this storage period. The calcium alginate bead-immobilised enzymes were further biochemically characterised and then applied in a bioreactor system for the production of D-hydroxyphenylglycine (D-HPG) from D,L-5-hydroxyphenylhydantoin (D,L-5-HPH). The pH and temperature optima for the immobilised hydantoinase were pH 7 and 50°C, respectively, while pH 8 and 40°C were optimal for the immobilised N-carbamoylase enzyme. The immobilised enzymes showed improved thermostability at 40°C in comparison to the free enzymes and retained high levels of activity after five repeated batch reactions. Low levels of conversion were obtained in a packed-bed bioreactor containing the A. tumefaciens RU-ORPN1 biocatalyst due to the low hydantoinase activity present in the strain, relative to N-carbamoylase. A novel, packed-bed bioreactor system was therefore developed for the production of D-HPG from D,L-5-HPH using the A. tumefaciens biocatalyst in combination with a Pseudomonas sp. biocatalyst having high hydantoinase activity. A conversion yield of 22 to 30% was achieved for the production of D-HPG from D,L-5-HPH over 5 days operation demonstrating that the hydantoin-hydrolysing enzymes from A. tumefaciens RU-ORPN1 could be stabilised by immobilisation and, in combination with a biocatalyst with high hydantoinase activity, could be applied to the fully enzymatic conversion of D,L-5-HPH to D-HPG.
- Full Text:
- Date Issued: 2004
- Authors: Foster, Ingrid Margaret
- Date: 2004
- Subjects: Agrobacterium tumefaciens Amino acids Hydantoin Hydrolysis Enzymes
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3943 , http://hdl.handle.net/10962/d1004002
- Description: A calcium alginate bead-immobilised biocatalyst was developed utilising the D-hydantoinase and D-N-carbamoylase from a novel, mutant Agrobacterium tumefaciens strain RU-ORPN1. The growth conditions for the inducer-independent strain were optimised for production of hydantoinase and N-carbamoylase activities. Methods for the preparation of crude enzyme extracts were evaluated in terms of hydantoinase and N-carbamoylase activities produced. After comparison of the enzyme activities and stabilities in various extracts from fresh and frozen cells, sonication of frozen cells for 5 minutes was found to be the best method for the production of the enzyme extract. The optimal pH and temperature for the hydantoinase activity were pH 10 and 30°C, respectively, while pH 9 and 40°C were optimal for Ncarbamoylase activity. The hydantoinase activity was enhanced by the addition of Mg^(2+) ions to the enzyme extract and the N-carbamoylase was enhanced by the addition of Mg^(2+), Mn^(2+) or Zn^(2+) ions to the enzyme extract. The enzyme activities increased in the presence of ATP suggesting that the enzymes may be ATP-dependent. The addition of DTT and PMSF to the enzyme extract enhanced the hydantoinase activity but had no effect on the N-carbamoylase activity. The N-carbamoylase was unstable at 40°C and was almost completely inactivated after 24 hours incubation at this temperature. The hydantoinase and N-carbamoylase appeared to be insoluble. Various techniques were investigated for the solubilisation of the enzymes including various cell lysis methods, cell lysis at extremes of pH and ionic strength, addition of a reducing agent and protease inhibitors, and treatment with hydrolysing enzymes and detergents. Treatment with Triton X-100 was most effective for the solubilisation of the enzymes indicating that the enzymes were membrane-bound. Hydropathy and transmembrane prediction plots of the predicted amino acid sequences for two identified N-carbamoylase genes from A. tumefaciens RU-ORPN1 revealed possible transmembrane regions in the amino acid sequences, and thus supported the hypothesis that the enzymes were membrane-bound. Various methods were evaluated for the immobilisation of the enzymes in whole cells and enzyme extracts. Immobilisation of the enzyme extract in calcium alginate beads was found to be the best method in terms of enzyme activity retention and stability. The hydantoinase retained 55% activity while the N-carbamoylase exhibited a remarkable sevenfold increase in activity after immobilisation by this method. Furthermore, the hydantoinase activity increased after storage at 4°C for 21 days, while the N-carbamoylase retained 30% activity after this storage period. The calcium alginate bead-immobilised enzymes were further biochemically characterised and then applied in a bioreactor system for the production of D-hydroxyphenylglycine (D-HPG) from D,L-5-hydroxyphenylhydantoin (D,L-5-HPH). The pH and temperature optima for the immobilised hydantoinase were pH 7 and 50°C, respectively, while pH 8 and 40°C were optimal for the immobilised N-carbamoylase enzyme. The immobilised enzymes showed improved thermostability at 40°C in comparison to the free enzymes and retained high levels of activity after five repeated batch reactions. Low levels of conversion were obtained in a packed-bed bioreactor containing the A. tumefaciens RU-ORPN1 biocatalyst due to the low hydantoinase activity present in the strain, relative to N-carbamoylase. A novel, packed-bed bioreactor system was therefore developed for the production of D-HPG from D,L-5-HPH using the A. tumefaciens biocatalyst in combination with a Pseudomonas sp. biocatalyst having high hydantoinase activity. A conversion yield of 22 to 30% was achieved for the production of D-HPG from D,L-5-HPH over 5 days operation demonstrating that the hydantoin-hydrolysing enzymes from A. tumefaciens RU-ORPN1 could be stabilised by immobilisation and, in combination with a biocatalyst with high hydantoinase activity, could be applied to the fully enzymatic conversion of D,L-5-HPH to D-HPG.
- Full Text:
- Date Issued: 2004
Die bestuursrol van die skoolhoof in die implementering van 'n nuwe kurrikulum
- Authors: Mey, Hermanus Pieter
- Date: 2004
- Subjects: School principals -- South Africa , Educational leadership -- South Africa , Curriculum change -- South Africa
- Language: Afrikaans
- Type: Thesis , Masters , MPhil
- Identifier: vital:11010 , http://hdl.handle.net/10948/367 , School principals -- South Africa , Educational leadership -- South Africa , Curriculum change -- South Africa
- Description: The implementation of a new curriculum has become a very relevant issue in South Africa with the implementation of Curriculum 2005 (C 2005) since 1998. The school principal plays a very important role at school level in the implementation of change in general and a new curriculum in particular. The aim of this study was to have a closer look at this role. It is a qualitative study executed in six schools in the Port Elizabeth area. It investigates the problems school principals experienced with the implementation of C 2005 with the objective of identifying guidelines for the role of the principal in the implementation of a new curriculum The most important findings include the importance of equipping the principal to provide guidance with the implementation of a new curriculum. This equipping refers to the principal’s knowledge of the new curriculum, the ability to employ various leadership styles, as well as the maintenance of a certain balance between supporting and putting pressure on the staff. Other findings refer to the importance of well-trained and prepared facilitators of workshops, as well as the role the Department of Education needs to play in the training and preparation of these facilitators. The ongoing support of schools in the implementation process also needs to be emphasized. The principal should play a key role with respect to this last role of the Department. The study also emphasizes the principal’s responsibility to bind the educators together in building a shared vision, so that their focus will remain on the curriculum implementation.
- Full Text:
- Date Issued: 2004
- Authors: Mey, Hermanus Pieter
- Date: 2004
- Subjects: School principals -- South Africa , Educational leadership -- South Africa , Curriculum change -- South Africa
- Language: Afrikaans
- Type: Thesis , Masters , MPhil
- Identifier: vital:11010 , http://hdl.handle.net/10948/367 , School principals -- South Africa , Educational leadership -- South Africa , Curriculum change -- South Africa
- Description: The implementation of a new curriculum has become a very relevant issue in South Africa with the implementation of Curriculum 2005 (C 2005) since 1998. The school principal plays a very important role at school level in the implementation of change in general and a new curriculum in particular. The aim of this study was to have a closer look at this role. It is a qualitative study executed in six schools in the Port Elizabeth area. It investigates the problems school principals experienced with the implementation of C 2005 with the objective of identifying guidelines for the role of the principal in the implementation of a new curriculum The most important findings include the importance of equipping the principal to provide guidance with the implementation of a new curriculum. This equipping refers to the principal’s knowledge of the new curriculum, the ability to employ various leadership styles, as well as the maintenance of a certain balance between supporting and putting pressure on the staff. Other findings refer to the importance of well-trained and prepared facilitators of workshops, as well as the role the Department of Education needs to play in the training and preparation of these facilitators. The ongoing support of schools in the implementation process also needs to be emphasized. The principal should play a key role with respect to this last role of the Department. The study also emphasizes the principal’s responsibility to bind the educators together in building a shared vision, so that their focus will remain on the curriculum implementation.
- Full Text:
- Date Issued: 2004
Die toepassing van die proses van geïntegreerde ontwikkelingsbeplanning deur kategorie B plaaslike owerhede
- Authors: Els, Christoffel Gerhardus
- Date: 2004
- Subjects: Local government -- South Africa , Public administration -- South Africa
- Language: Afrikaans
- Type: Thesis , Masters , MTech (Public Management)
- Identifier: vital:10768 , http://hdl.handle.net/10948/266 , Local government -- South Africa , Public administration -- South Africa
- Description: Samevattende oorsig: In hierdie skripsie, is 'n studie onderneem ten opsigte van die Geïntegreerde Ontwikkelingsbeplanningsproses, wat die proses van beplanning en die toepassing van hierdie beplanningsresultate ten opsigte van twee klein B-munisipaliteite in die Wes-Kaap Provinsie insluit. Die skripsie bestaan uit sewe hoofstukke en is gebaseer op die veronderstelling dat die beplanningsproses van so 'n tegniese aard is dat kleiner owerhede nie in staat is om die proses na behore te kan bestuur nie. Dit gaan verder van die onderstelling uit dat die implementeeringskapasiteit by kleiner owerhede ontbreek om dievoorsiene uitkomste na behore te realiseer. Die primêre doelwitte van die navorsing sluit die volgende in: 'n basiese oorsig van openbare bestuur, die rolle en funksies van funksionarisse binne hierdie omgewing en die veranderende aard van openbare bestuur. Die proses van geïntegreerde ontwikkelingsbeplanning binne plaaslike regering word bestudeer met 'n volledige proses toeligting. Die noodsaaklikheid van beplanning en prestasiebestuur word bevestig tesame met die uitdagings en probleme wat die nuwe benadering bring aan klein plaaslike owerhede. 'n Finale waardebepaling rond die studie af. Die studie bestaan uit bronnavorsing om die veranderende aard van openbare bestuur toe te lig tesame met die werklike aard van die beplanningsproses soos vereis binne relevante wetgewing. Die impak van hierdie vereistes op klein plaaslike owerhede in die Wes-Kaap word ontleed aan die hand van twee geïntegreerde ontwikkelingsplanne soos deur die skrywer hiervan gefasiliteer by dié owerhede. Die gevolgtrekkings gemaak uit hierdie studie word dan ook aangedui met 'n aanbeveling oor die mees sinvolle inkrementele benadering ten opsigte van ontwikkeling as proses en die deelname van rolspelers daarbinne.
- Full Text:
- Date Issued: 2004
- Authors: Els, Christoffel Gerhardus
- Date: 2004
- Subjects: Local government -- South Africa , Public administration -- South Africa
- Language: Afrikaans
- Type: Thesis , Masters , MTech (Public Management)
- Identifier: vital:10768 , http://hdl.handle.net/10948/266 , Local government -- South Africa , Public administration -- South Africa
- Description: Samevattende oorsig: In hierdie skripsie, is 'n studie onderneem ten opsigte van die Geïntegreerde Ontwikkelingsbeplanningsproses, wat die proses van beplanning en die toepassing van hierdie beplanningsresultate ten opsigte van twee klein B-munisipaliteite in die Wes-Kaap Provinsie insluit. Die skripsie bestaan uit sewe hoofstukke en is gebaseer op die veronderstelling dat die beplanningsproses van so 'n tegniese aard is dat kleiner owerhede nie in staat is om die proses na behore te kan bestuur nie. Dit gaan verder van die onderstelling uit dat die implementeeringskapasiteit by kleiner owerhede ontbreek om dievoorsiene uitkomste na behore te realiseer. Die primêre doelwitte van die navorsing sluit die volgende in: 'n basiese oorsig van openbare bestuur, die rolle en funksies van funksionarisse binne hierdie omgewing en die veranderende aard van openbare bestuur. Die proses van geïntegreerde ontwikkelingsbeplanning binne plaaslike regering word bestudeer met 'n volledige proses toeligting. Die noodsaaklikheid van beplanning en prestasiebestuur word bevestig tesame met die uitdagings en probleme wat die nuwe benadering bring aan klein plaaslike owerhede. 'n Finale waardebepaling rond die studie af. Die studie bestaan uit bronnavorsing om die veranderende aard van openbare bestuur toe te lig tesame met die werklike aard van die beplanningsproses soos vereis binne relevante wetgewing. Die impak van hierdie vereistes op klein plaaslike owerhede in die Wes-Kaap word ontleed aan die hand van twee geïntegreerde ontwikkelingsplanne soos deur die skrywer hiervan gefasiliteer by dié owerhede. Die gevolgtrekkings gemaak uit hierdie studie word dan ook aangedui met 'n aanbeveling oor die mees sinvolle inkrementele benadering ten opsigte van ontwikkeling as proses en die deelname van rolspelers daarbinne.
- Full Text:
- Date Issued: 2004
Discourse domination?: the role of gender in seminar interaction
- De Klerk, Vivian A, Hunt, Sally
- Authors: De Klerk, Vivian A , Hunt, Sally
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/139160 , vital:37710 , https://www.ajol.info/index.php/salas/article/view/6501
- Description: This paper focuses on the effect of the gender of participants on the discourse patterns of university seminars, and compares the interaction patterns in two undergraduate seminars with those in two post-graduate seminars at Rhodes University. In the undergraduate seminars, two different groups of students at first year level in different disciplines were videotaped. The major difference was in terms of composition: in one seminar, there were equal numbers of male and female students, while in the other, female students dominated numerically (75%). In addition, five of the six formed a close-knit group of friends, which proved to be an important factor in the analysis. At the postgraduate level, the student participants were identical and met in the same venue and at the same time on two successive days to discuss the same topic (affirmative action in the workplace). The important difference between the two classes was the fact that the first seminar was led by a female tutor and the second seminar by a male tutor, both under 40 years of age and white, both members of staff in the department, and both known to the students. The discourse patterns in these two sets of seminars were analysed in order to investigate the ways in which the gender of tutors and students influenced the floor-winning and floor-holding conventions of participants.
- Full Text:
- Date Issued: 2004
- Authors: De Klerk, Vivian A , Hunt, Sally
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/139160 , vital:37710 , https://www.ajol.info/index.php/salas/article/view/6501
- Description: This paper focuses on the effect of the gender of participants on the discourse patterns of university seminars, and compares the interaction patterns in two undergraduate seminars with those in two post-graduate seminars at Rhodes University. In the undergraduate seminars, two different groups of students at first year level in different disciplines were videotaped. The major difference was in terms of composition: in one seminar, there were equal numbers of male and female students, while in the other, female students dominated numerically (75%). In addition, five of the six formed a close-knit group of friends, which proved to be an important factor in the analysis. At the postgraduate level, the student participants were identical and met in the same venue and at the same time on two successive days to discuss the same topic (affirmative action in the workplace). The important difference between the two classes was the fact that the first seminar was led by a female tutor and the second seminar by a male tutor, both under 40 years of age and white, both members of staff in the department, and both known to the students. The discourse patterns in these two sets of seminars were analysed in order to investigate the ways in which the gender of tutors and students influenced the floor-winning and floor-holding conventions of participants.
- Full Text:
- Date Issued: 2004
Dismissal for medical incapacity
- Authors: Boy, Anthony Albert
- Date: 2004
- Subjects: Employees -- Dismissal of -- Law and legislation -- South Africa , Capacity and disability -- South Africa , Labor laws and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11047 , http://hdl.handle.net/10948/316 , Employees -- Dismissal of -- Law and legislation -- South Africa , Capacity and disability -- South Africa , Labor laws and legislation -- South Africa
- Description: Labour law in South Africa has evolved over the past century at an ever increasing pace. The establishment of a democratic government in 1995 has been the trigger for a large number of labour law statutes being promulgated, particularly with reference to the laws governing the employment relationship and dismissal. From very humble and employer biased dispute resolution application under the common law of contract, labour law in this country has evolved through the various acts culminating in a labour law system which is highly regulated and codified. Dismissal for medical incapacity in this treatise is reviewed with regard to the applicable statutes and the various codes of good practice as the law has evolved and developed from the period covered by the common law through that covered by the 1995 LRA up to and including the current period. Particular attention is paid to both substantive and procedural requirements as well as the remedies applicable under the different legal regimes and the pertinent tribunals and courts. Regard is also given to the duration and causes of incapacity and the effect this may have on the applicable remedy applied by these tribunals. It will become apparant that the medically incapacitated employee occupied a relatively weak and vulnerable position under the common law as opposed to the current position under the 1995 LRA. The influence of the remedies applied by the tribunals under the 1956 LRA are clearly evident in the current regulations and codes under the 1995 LRA which contain specific statutory provisions for employees not to be unfairly dismissed. Distinctions are drawn between permissible and impermissible dismissals, with medical incapacity falling under the former. v Furthermore, a distinction is drawn statutorily between permanent and temporary illhealth/ injury incapacity with detailed guidelines for substantive and procedural fairness requirements to be met by employers. The powers of the specialist tribunals (CCMA, Bargaining Councils and Labour Courts) are regulated by statutory provisions and deal with appropriate remedies (reinstatement and/or compensation) a wardable in appropriate circumstances. Certain specific areas nonetheless still remain problematic for these tribunals and hence questions that require clear direction from the drafters of our law are: 1. How to distinguish misconduct in alcohol and drug abuse cases? 2. What degree of intermittent absenteeism is required before dismissal would be warranted? In certain other areas the tribunals have been fairly consistent and prescriptive in their approach and remedies awarded. Included here would be permanent incapacity, HIV cases and misconduct. It will emerge, however, that under the 1995 LRA the position of employees and the protections afforded them have been greatly increased.
- Full Text:
- Date Issued: 2004
- Authors: Boy, Anthony Albert
- Date: 2004
- Subjects: Employees -- Dismissal of -- Law and legislation -- South Africa , Capacity and disability -- South Africa , Labor laws and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:11047 , http://hdl.handle.net/10948/316 , Employees -- Dismissal of -- Law and legislation -- South Africa , Capacity and disability -- South Africa , Labor laws and legislation -- South Africa
- Description: Labour law in South Africa has evolved over the past century at an ever increasing pace. The establishment of a democratic government in 1995 has been the trigger for a large number of labour law statutes being promulgated, particularly with reference to the laws governing the employment relationship and dismissal. From very humble and employer biased dispute resolution application under the common law of contract, labour law in this country has evolved through the various acts culminating in a labour law system which is highly regulated and codified. Dismissal for medical incapacity in this treatise is reviewed with regard to the applicable statutes and the various codes of good practice as the law has evolved and developed from the period covered by the common law through that covered by the 1995 LRA up to and including the current period. Particular attention is paid to both substantive and procedural requirements as well as the remedies applicable under the different legal regimes and the pertinent tribunals and courts. Regard is also given to the duration and causes of incapacity and the effect this may have on the applicable remedy applied by these tribunals. It will become apparant that the medically incapacitated employee occupied a relatively weak and vulnerable position under the common law as opposed to the current position under the 1995 LRA. The influence of the remedies applied by the tribunals under the 1956 LRA are clearly evident in the current regulations and codes under the 1995 LRA which contain specific statutory provisions for employees not to be unfairly dismissed. Distinctions are drawn between permissible and impermissible dismissals, with medical incapacity falling under the former. v Furthermore, a distinction is drawn statutorily between permanent and temporary illhealth/ injury incapacity with detailed guidelines for substantive and procedural fairness requirements to be met by employers. The powers of the specialist tribunals (CCMA, Bargaining Councils and Labour Courts) are regulated by statutory provisions and deal with appropriate remedies (reinstatement and/or compensation) a wardable in appropriate circumstances. Certain specific areas nonetheless still remain problematic for these tribunals and hence questions that require clear direction from the drafters of our law are: 1. How to distinguish misconduct in alcohol and drug abuse cases? 2. What degree of intermittent absenteeism is required before dismissal would be warranted? In certain other areas the tribunals have been fairly consistent and prescriptive in their approach and remedies awarded. Included here would be permanent incapacity, HIV cases and misconduct. It will emerge, however, that under the 1995 LRA the position of employees and the protections afforded them have been greatly increased.
- Full Text:
- Date Issued: 2004
Dismissal for medical incapacity
- Authors: Boy, Anthony Albert
- Date: 2004
- Subjects: Employees -- Dismissal of -- Law and legislation -- South Africa , Capacity and disability -- South Africa , Labor laws and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10242 , http://hdl.handle.net/10948/d1016262
- Description: Labour law in South Africa has evolved over the past century at an ever increasing pace. The establishment of a democratic government in 1995 has been the trigger for a large number of labour law statutes being promulgated, particularly with reference to the laws governing the employment relationship and dismissal. From very humble and employer biased dispute resolution application under the common law of contract, labour law in this country has evolved through the various acts culminating in a labour law system which is highly regulated and codified. Dismissal for medical incapacity in this treatise is reviewed with regard to the applicable statutes and the various codes of good practice as the law has evolved and developed from the period covered by the common law through that covered by the 1995 LRA up to and including the current period. Particular attention is paid to both substantive and procedural requirements as well as the remedies applicable under the different legal regimes and the pertinent tribunals and courts. Regard is also given to the duration and causes of incapacity and the effect this may have on the applicable remedy applied by these tribunals. It will become apparant that the medically incapacitated employee occupied a relatively weak and vulnerable position under the common law as opposed to the current position under the 1995 LRA. The influence of the remedies applied by the tribunals under the 1956 LRA are clearly evident in the current regulations and codes under the 1995 LRA which contain specific statutory provisions for employees not to be unfairly dismissed. Distinctions are drawn between permissible and impermissible dismissals, with medical incapacity falling under the former. Furthermore, a distinction is drawn statutorily between permanent and temporary illhealth/injury incapacity with detailed guidelines for substantive and procedural fairness requirements to be met by employers. The powers of the specialist tribunals (CCMA, Bargaining Councils and Labour Courts) are regulated by statutory provisions and deal with appropriate remedies (reinstatement and/or compensation) a wardable in appropriate circumstances. Certain specific areas nonetheless still remain problematic for these tribunals and hence questions that require clear direction from the drafters of our law are: How to distinguish misconduct in alcohol and drug abuse cases? What degree of intermittent absenteeism is required before dismissal would be warranted? In certain other areas the tribunals have been fairly consistent and prescriptive in their approach and remedies awarded. Included here would be permanent incapacity, HIV cases and misconduct. It will emerge, however, that under the 1995 LRA the position of employees and the protections afforded them have been greatly increased.
- Full Text:
- Date Issued: 2004
- Authors: Boy, Anthony Albert
- Date: 2004
- Subjects: Employees -- Dismissal of -- Law and legislation -- South Africa , Capacity and disability -- South Africa , Labor laws and legislation -- South Africa
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: vital:10242 , http://hdl.handle.net/10948/d1016262
- Description: Labour law in South Africa has evolved over the past century at an ever increasing pace. The establishment of a democratic government in 1995 has been the trigger for a large number of labour law statutes being promulgated, particularly with reference to the laws governing the employment relationship and dismissal. From very humble and employer biased dispute resolution application under the common law of contract, labour law in this country has evolved through the various acts culminating in a labour law system which is highly regulated and codified. Dismissal for medical incapacity in this treatise is reviewed with regard to the applicable statutes and the various codes of good practice as the law has evolved and developed from the period covered by the common law through that covered by the 1995 LRA up to and including the current period. Particular attention is paid to both substantive and procedural requirements as well as the remedies applicable under the different legal regimes and the pertinent tribunals and courts. Regard is also given to the duration and causes of incapacity and the effect this may have on the applicable remedy applied by these tribunals. It will become apparant that the medically incapacitated employee occupied a relatively weak and vulnerable position under the common law as opposed to the current position under the 1995 LRA. The influence of the remedies applied by the tribunals under the 1956 LRA are clearly evident in the current regulations and codes under the 1995 LRA which contain specific statutory provisions for employees not to be unfairly dismissed. Distinctions are drawn between permissible and impermissible dismissals, with medical incapacity falling under the former. Furthermore, a distinction is drawn statutorily between permanent and temporary illhealth/injury incapacity with detailed guidelines for substantive and procedural fairness requirements to be met by employers. The powers of the specialist tribunals (CCMA, Bargaining Councils and Labour Courts) are regulated by statutory provisions and deal with appropriate remedies (reinstatement and/or compensation) a wardable in appropriate circumstances. Certain specific areas nonetheless still remain problematic for these tribunals and hence questions that require clear direction from the drafters of our law are: How to distinguish misconduct in alcohol and drug abuse cases? What degree of intermittent absenteeism is required before dismissal would be warranted? In certain other areas the tribunals have been fairly consistent and prescriptive in their approach and remedies awarded. Included here would be permanent incapacity, HIV cases and misconduct. It will emerge, however, that under the 1995 LRA the position of employees and the protections afforded them have been greatly increased.
- Full Text:
- Date Issued: 2004
Distinct kimberlite pipe classes with contrasting eruption processes
- Skinner, E M W, Marsh, Julian S
- Authors: Skinner, E M W , Marsh, Julian S
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150603 , vital:38988 , https://doi.org/10.1016/j.lithos.2004.03.044
- Description: Field and Scott Smith [Field, M., Scott Smith, B.H., 1999. Contrasting geology and near-surface emplacement of kimberlite pipes in southern Africa and Canada. Proc. 7th Int. Kimb. Conf. (Eds. Gurney et al.) 1, 214–237.] propose that kimberlite pipes can be grouped into three types or classes. Classical or Class 1 pipes are the only class with characteristic low temperature, diatreme-facies kimberlite in addition to hypabyssal- and crater-facies kimberlite. Class 2 and 3 pipes are characterized only by hypabyssal-and crater-facies kimberlite.
- Full Text: false
- Date Issued: 2004
- Authors: Skinner, E M W , Marsh, Julian S
- Date: 2004
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/150603 , vital:38988 , https://doi.org/10.1016/j.lithos.2004.03.044
- Description: Field and Scott Smith [Field, M., Scott Smith, B.H., 1999. Contrasting geology and near-surface emplacement of kimberlite pipes in southern Africa and Canada. Proc. 7th Int. Kimb. Conf. (Eds. Gurney et al.) 1, 214–237.] propose that kimberlite pipes can be grouped into three types or classes. Classical or Class 1 pipes are the only class with characteristic low temperature, diatreme-facies kimberlite in addition to hypabyssal- and crater-facies kimberlite. Class 2 and 3 pipes are characterized only by hypabyssal-and crater-facies kimberlite.
- Full Text: false
- Date Issued: 2004
Drimia chalumnensis (Hyacinthaceae - Urgineoideae), a new species from Eastern Cape, South Africa
- Dold, Anthony P, Brink, Estelle
- Authors: Dold, Anthony P , Brink, Estelle
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6516 , http://hdl.handle.net/10962/d1005944
- Description: Drimia chalumnensis, a new inconspicuous dwarf species from the Albany Centre of Floristic Endemism in Eastern Cape, South Africa, is restricted to the coastal plains of the Chalumna river in small scattered aggregated colonies on exposed sandstone sheets in pockets of loose sandy soil. It is distinguished by its capitate inflorescence, separate, petiolate bulb scales, and prostrate, coriaceous, linear-lanceolate leaves with cartilaginous margins.
- Full Text:
- Date Issued: 2004
- Authors: Dold, Anthony P , Brink, Estelle
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6516 , http://hdl.handle.net/10962/d1005944
- Description: Drimia chalumnensis, a new inconspicuous dwarf species from the Albany Centre of Floristic Endemism in Eastern Cape, South Africa, is restricted to the coastal plains of the Chalumna river in small scattered aggregated colonies on exposed sandstone sheets in pockets of loose sandy soil. It is distinguished by its capitate inflorescence, separate, petiolate bulb scales, and prostrate, coriaceous, linear-lanceolate leaves with cartilaginous margins.
- Full Text:
- Date Issued: 2004
DRUBIS : a distributed face-identification experimentation framework - design, implementation and performance issues
- Authors: Ndlangisa, Mboneli
- Date: 2004
- Subjects: Principal components analysis , Human face recognition (Computer science) , Image processing , Biometric identification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4704 , http://hdl.handle.net/10962/d1015768
- Description: We report on the design, implementation and performance issues of the DRUBIS (Distributed Rhodes University Biometric Identification System) experimentation framework. The Principal Component Analysis (PCA) face-recognition approach is used as a case study. DRUBIS is a flexible experimentation framework, distributed over a number of modules that are easily pluggable and swappable, allowing for the easy construction of prototype systems. Web services are the logical means of distributing DRUBIS components and a number of prototype applications have been implemented from this framework. Different popular PCA face-recognition related experiments were used to evaluate our experimentation framework. We extract recognition performance measures from these experiments. In particular, we use the framework for a more indepth study of the suitability of the DFFS (Difference From Face Space) metric as a means for image classification in the area of race and gender determination.
- Full Text:
- Date Issued: 2004
- Authors: Ndlangisa, Mboneli
- Date: 2004
- Subjects: Principal components analysis , Human face recognition (Computer science) , Image processing , Biometric identification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4704 , http://hdl.handle.net/10962/d1015768
- Description: We report on the design, implementation and performance issues of the DRUBIS (Distributed Rhodes University Biometric Identification System) experimentation framework. The Principal Component Analysis (PCA) face-recognition approach is used as a case study. DRUBIS is a flexible experimentation framework, distributed over a number of modules that are easily pluggable and swappable, allowing for the easy construction of prototype systems. Web services are the logical means of distributing DRUBIS components and a number of prototype applications have been implemented from this framework. Different popular PCA face-recognition related experiments were used to evaluate our experimentation framework. We extract recognition performance measures from these experiments. In particular, we use the framework for a more indepth study of the suitability of the DFFS (Difference From Face Space) metric as a means for image classification in the area of race and gender determination.
- Full Text:
- Date Issued: 2004
Economic feasibility of an experimental octopus fishery in South Africa
- Authors: Oosthuizen, Ané
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6760 , http://hdl.handle.net/10962/d1007773
- Description: Octopus vulgaris was identified as a new marine resource to be commercially exploited through an experimental fishery. A recent policy on developing fisheries in South Africa emphasizes the importance of investigating the economic feasibility of a fishery as part of its management framework. The study reported here generated baseline information necessary in the design of the experimental fishery, giving guidelines as to which vessels, fishing gear and markets would be most feasible. The proposed fishery, gear and vessel type, fishing techniques and expected catch rates are described, the results of market research are outlined, and the cost of fishing is estimated. The potential business should consist of small and medium-sized vessels deploying unbaited pots attached to long lines. The longline pot fishery could be economically feasible, provided a 30 percent catch in 6600 pots/month is attained. Only existing, debt-free vessels should be used. The minimum catch per unit effort (CPUE) for various fishing operation scenarios was calculated to determine economic feasibility. This is an estimated minimum CPUE, based on assumptions that cannot be confirmed until the fishery starts. Furthermore, this economic analysis also needs to be assessed by stakeholders with experience of fishery operations , Rhodes Centenary issue of: South African Journal of Science.
- Full Text:
- Date Issued: 2004
- Authors: Oosthuizen, Ané
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6760 , http://hdl.handle.net/10962/d1007773
- Description: Octopus vulgaris was identified as a new marine resource to be commercially exploited through an experimental fishery. A recent policy on developing fisheries in South Africa emphasizes the importance of investigating the economic feasibility of a fishery as part of its management framework. The study reported here generated baseline information necessary in the design of the experimental fishery, giving guidelines as to which vessels, fishing gear and markets would be most feasible. The proposed fishery, gear and vessel type, fishing techniques and expected catch rates are described, the results of market research are outlined, and the cost of fishing is estimated. The potential business should consist of small and medium-sized vessels deploying unbaited pots attached to long lines. The longline pot fishery could be economically feasible, provided a 30 percent catch in 6600 pots/month is attained. Only existing, debt-free vessels should be used. The minimum catch per unit effort (CPUE) for various fishing operation scenarios was calculated to determine economic feasibility. This is an estimated minimum CPUE, based on assumptions that cannot be confirmed until the fishery starts. Furthermore, this economic analysis also needs to be assessed by stakeholders with experience of fishery operations , Rhodes Centenary issue of: South African Journal of Science.
- Full Text:
- Date Issued: 2004
Effects of substituents and solvents on the photochemical properties of zinc phthalocyanine complexes and their protonated derivatives
- Ogunsipe, Abimbola Olukayode, Nyokong, Tebello
- Authors: Ogunsipe, Abimbola Olukayode , Nyokong, Tebello
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6585 , http://hdl.handle.net/10962/d1004161
- Description: Zinc phthalocyanine derivatives containing various ring substituents and axial ligands were studied with respect to the effect of substituents on protonation. Aggregation resulted in failure of some of the ZnPc derivatives to protonate. In fact addition of protonating agents to aggregated ZnPc derivatives resulted in increase in aggregation followed by slow degradation. Axial ligands were lost on protonation. Photobleaching, fluorescence and singlet oxygen quantum yields of the protonated derivatives were compared with those of the unprotonated derivatives. In all cases protonation decreases the singlet oxygen and fluorescence quantum yields. However, photobleaching quantum yields decreased (i.e. stability increased) for the protonated derivatives except when axial ligands were present, where protonation resulted in decrease in stability.
- Full Text:
- Date Issued: 2004
- Authors: Ogunsipe, Abimbola Olukayode , Nyokong, Tebello
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6585 , http://hdl.handle.net/10962/d1004161
- Description: Zinc phthalocyanine derivatives containing various ring substituents and axial ligands were studied with respect to the effect of substituents on protonation. Aggregation resulted in failure of some of the ZnPc derivatives to protonate. In fact addition of protonating agents to aggregated ZnPc derivatives resulted in increase in aggregation followed by slow degradation. Axial ligands were lost on protonation. Photobleaching, fluorescence and singlet oxygen quantum yields of the protonated derivatives were compared with those of the unprotonated derivatives. In all cases protonation decreases the singlet oxygen and fluorescence quantum yields. However, photobleaching quantum yields decreased (i.e. stability increased) for the protonated derivatives except when axial ligands were present, where protonation resulted in decrease in stability.
- Full Text:
- Date Issued: 2004