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
Navigating between information security management documents : a modeling methodology
- Authors: Domingues, Steve
- Date: 2010
- Subjects: Computer security -- Management , Business -- Data processing -- Security measures , Information resources management -- Security measures , Business -- Standards
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9761 , http://hdl.handle.net/10948/1212 , Computer security -- Management , Business -- Data processing -- Security measures , Information resources management -- Security measures , Business -- Standards
- Description: Organizations no longer draft their own standards. Instead, organizations take advantage of the available international standards. One standard may not cover all the organization's needs, requiring organizations to implement more than one standard. The same aspect in an organization may be covered by two or more standards, creating an overlap. An awareness of such overlaps led to various institutions creating mapping documents illustrating how a control from one standard relates to a control from a different standard. The mapping documents are consulted by the end user, to identify how a control in one standard may relate to other standards. This allows the end user to navigate between the standards documents. These mapping documents are valuable to a person who wishes to grasp how different standards deal with a specific control. However, the navigation between standards is a cumbersome task. In order to navigate between the standards the end user is required to consult three or more documents, depending on the number of standards that are mapped to the control being investigated. The need for a tool that will provide fast and efficient navigation between standards was identified. The data tier of the tool is the focus of this dissertation. As a result, this research proposes a modeling methodology that will allow for the modeling of the standards and the information about the mapping between standards, thereby contributing to the creation of tools to aid in the navigation between standards. A comparison between the major data modeling paradigms identifies multi-dimensional modeling as the most appropriate technique to model standards. Adapting an existing modeling methodology to cater for the modeling standards, yield a five step standard modeling methodology. Once modeled, the standards can be physically implemented as a database. The database schema that results from the standard modeling methodology adheres to a specific pattern and can thus be expressed according to well-defined meta-model. This allows for the generation of SQL statements by a tool with limited knowledge of the standards in a way that allows the quick navigation between standards. To determine the usefulness of the standards modeling methodology the research presents iv a prototype that utilizes the well-defined meta-model to navigate between standards. It is shown that, as far as navigation is concerned, no code changes are necessary when adding a new standard or new mappings between standards. This research contributes to the creation of a tool that can easily navigate between standards by providing the ability to model the data tier in such a way that it is extensible, yet remains independent of the application and presentation tiers.
- Full Text:
- Date Issued: 2010
- Authors: Domingues, Steve
- Date: 2010
- Subjects: Computer security -- Management , Business -- Data processing -- Security measures , Information resources management -- Security measures , Business -- Standards
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9761 , http://hdl.handle.net/10948/1212 , Computer security -- Management , Business -- Data processing -- Security measures , Information resources management -- Security measures , Business -- Standards
- Description: Organizations no longer draft their own standards. Instead, organizations take advantage of the available international standards. One standard may not cover all the organization's needs, requiring organizations to implement more than one standard. The same aspect in an organization may be covered by two or more standards, creating an overlap. An awareness of such overlaps led to various institutions creating mapping documents illustrating how a control from one standard relates to a control from a different standard. The mapping documents are consulted by the end user, to identify how a control in one standard may relate to other standards. This allows the end user to navigate between the standards documents. These mapping documents are valuable to a person who wishes to grasp how different standards deal with a specific control. However, the navigation between standards is a cumbersome task. In order to navigate between the standards the end user is required to consult three or more documents, depending on the number of standards that are mapped to the control being investigated. The need for a tool that will provide fast and efficient navigation between standards was identified. The data tier of the tool is the focus of this dissertation. As a result, this research proposes a modeling methodology that will allow for the modeling of the standards and the information about the mapping between standards, thereby contributing to the creation of tools to aid in the navigation between standards. A comparison between the major data modeling paradigms identifies multi-dimensional modeling as the most appropriate technique to model standards. Adapting an existing modeling methodology to cater for the modeling standards, yield a five step standard modeling methodology. Once modeled, the standards can be physically implemented as a database. The database schema that results from the standard modeling methodology adheres to a specific pattern and can thus be expressed according to well-defined meta-model. This allows for the generation of SQL statements by a tool with limited knowledge of the standards in a way that allows the quick navigation between standards. To determine the usefulness of the standards modeling methodology the research presents iv a prototype that utilizes the well-defined meta-model to navigate between standards. It is shown that, as far as navigation is concerned, no code changes are necessary when adding a new standard or new mappings between standards. This research contributes to the creation of a tool that can easily navigate between standards by providing the ability to model the data tier in such a way that it is extensible, yet remains independent of the application and presentation tiers.
- Full Text:
- Date Issued: 2010
An in-line measuring technique with tool error detection in an automotive production line
- Authors: Viol, Florian
- Date: 2010
- Subjects: Automobile industry and trade -- Quality control
- Language: English
- Type: Thesis , Masters , MEngineering
- Identifier: vital:9647 , http://hdl.handle.net/10948/1327 , Automobile industry and trade -- Quality control
- Description: The modern automobile industry faces an increasing demand on personalized high quality products. In order to stay competitive the automobile manufacturers have to ensure the customers high quality demands. With the increasing amount of applied parts and components manufacturing processes are becoming more complex. The recent quality assurance of the manufacturers considers only the product quality. Furthermore are with the recent quality assurance methods only punctual integrations of quality assurance tools in production chains possible. These limitations cause a large quality control loop. This leads in case of defective parts to an enormous time and money effort to track the cause for the defect. This project presents an innovative measurement strategy of quality assurance within the modern automobile production which will minimize the control loop and identify the tool causing the defect in the part. It highlights the possibility to integrate equipment for quality assurance directly into the production cell itself and analyse the geometrical conditions within the manufacturing processes. The result of this thesis is a fully automated prototype which is installed into the actual production of the Volkswagen Golf assembly. The prototype system consists on the one hand out of different on the market free available hardware and software components. On the other hand there are specifically for this prototype developed hardware components and software tools. For the first time it is possible to inspect the geometrical conditions of one tool continuously during production and identify, if occurring, deviations in the tool in position direction and size. The installation of similar systems in the production will minimize the control loops of the production. The chance of early recognition of errors will reduce the efforts and cost of error backtracking. In ideal conditions this instrument will identify defective tools before a product is manufactured. This innovative quality tool is the ideal addition to the current quality assurance and is the first link between the product quality and the geometrical conditions of the tools.
- Full Text:
- Date Issued: 2010
- Authors: Viol, Florian
- Date: 2010
- Subjects: Automobile industry and trade -- Quality control
- Language: English
- Type: Thesis , Masters , MEngineering
- Identifier: vital:9647 , http://hdl.handle.net/10948/1327 , Automobile industry and trade -- Quality control
- Description: The modern automobile industry faces an increasing demand on personalized high quality products. In order to stay competitive the automobile manufacturers have to ensure the customers high quality demands. With the increasing amount of applied parts and components manufacturing processes are becoming more complex. The recent quality assurance of the manufacturers considers only the product quality. Furthermore are with the recent quality assurance methods only punctual integrations of quality assurance tools in production chains possible. These limitations cause a large quality control loop. This leads in case of defective parts to an enormous time and money effort to track the cause for the defect. This project presents an innovative measurement strategy of quality assurance within the modern automobile production which will minimize the control loop and identify the tool causing the defect in the part. It highlights the possibility to integrate equipment for quality assurance directly into the production cell itself and analyse the geometrical conditions within the manufacturing processes. The result of this thesis is a fully automated prototype which is installed into the actual production of the Volkswagen Golf assembly. The prototype system consists on the one hand out of different on the market free available hardware and software components. On the other hand there are specifically for this prototype developed hardware components and software tools. For the first time it is possible to inspect the geometrical conditions of one tool continuously during production and identify, if occurring, deviations in the tool in position direction and size. The installation of similar systems in the production will minimize the control loops of the production. The chance of early recognition of errors will reduce the efforts and cost of error backtracking. In ideal conditions this instrument will identify defective tools before a product is manufactured. This innovative quality tool is the ideal addition to the current quality assurance and is the first link between the product quality and the geometrical conditions of the tools.
- Full Text:
- Date Issued: 2010
Characterisation of dissimilar friction stir welds between 5754 Aluminium alloy and C11000 copper
- Authors: Akinlabi, Esther Titilayo
- Date: 2010
- Subjects: Friction stir welding , Aluminum alloys , Copper alloys
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:9629 , http://hdl.handle.net/10948/1536 , Friction stir welding , Aluminum alloys , Copper alloys
- Description: Friction Stir Welding (FSW) is a solid state welding process invented and patented by The Welding Institute (TWI) in 1991, for joining ferrous and non-ferrous materials1. The FSW of Aluminium and its alloys has been commercialised; and recent interest is focused on joining dissimilar materials. However, in order to commercialise the process, research studies are required to characterise and establish process windows. This research work through material characterisation of the welded joints establishes a process window for the Friction Stir welding of 5754 Aluminium Alloy and C11000 Copper. Furthermore, preliminary studies83,85 on the FSW of aluminium and copper have revealed the presence of intermetallic compounds which are detrimental to the weld qualities. This research work is also aimed at establishing process parameters that will result in limited or no intermetallic formation in the weld. The joint integrity of the resulting welds will also be correlated with the input process parameters. Based on the preliminary investigations conducted, a final weld matrix consisting of twenty seven welds was produced by varying the rotational speed between 600 and 1200 rpm, and the feed rate between 50 and 300 mm/min using three different shoulder diameter tools – 15, 18 and 25 mm to compare the heat input into the welds and to achieve the best results. The welds were characterised through microstructural evaluation, tensile testing, microhardness profiling, X-Ray Diffraction analysis, electrical resistivity and statistical analysis – in order to establish the interrelationship between the process parameters and the weld qualities. viii Microstructural evaluation of the weld samples revealed that the interfacial regions are characterised by mixture layers of aluminium and copper; while 33 percent of the tensile samples are within the acceptable range (> 75 percent joint efficiency). High Vickers microhardness values were measured at the joint interfaces, which corresponded with the intermetallic compounds. The Energy Dispersive Spectroscopy analysis revealed the presence of thin layers of intermetallics in nanoscale at the interfacial regions. The diffractograms of the X-Ray Diffraction analysis showed small peaks for intermetallics in some of the welds. Low electrical resistivities were measured at the joint interfaces. The statistical analysis showed that the downward vertical force, (Fz) can significantly influence the resulting weld qualities. An overall summary of the analysis of the weld qualities - with respect to the shoulder diameter tools employed showed that the 18 mm shoulder diameter tool is most appropriate among the three shoulder diameters considered, and a process window of medium spindle speed of 950 rpm and low-to-medium feed rate between 50 and 150 mm/min is established for FSW of Aluminium and Copper. Welds produced at 1200 rpm and 300 mm/min with low heat input did not have intermetallics formed at the joint interface.
- Full Text:
- Date Issued: 2010
- Authors: Akinlabi, Esther Titilayo
- Date: 2010
- Subjects: Friction stir welding , Aluminum alloys , Copper alloys
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: vital:9629 , http://hdl.handle.net/10948/1536 , Friction stir welding , Aluminum alloys , Copper alloys
- Description: Friction Stir Welding (FSW) is a solid state welding process invented and patented by The Welding Institute (TWI) in 1991, for joining ferrous and non-ferrous materials1. The FSW of Aluminium and its alloys has been commercialised; and recent interest is focused on joining dissimilar materials. However, in order to commercialise the process, research studies are required to characterise and establish process windows. This research work through material characterisation of the welded joints establishes a process window for the Friction Stir welding of 5754 Aluminium Alloy and C11000 Copper. Furthermore, preliminary studies83,85 on the FSW of aluminium and copper have revealed the presence of intermetallic compounds which are detrimental to the weld qualities. This research work is also aimed at establishing process parameters that will result in limited or no intermetallic formation in the weld. The joint integrity of the resulting welds will also be correlated with the input process parameters. Based on the preliminary investigations conducted, a final weld matrix consisting of twenty seven welds was produced by varying the rotational speed between 600 and 1200 rpm, and the feed rate between 50 and 300 mm/min using three different shoulder diameter tools – 15, 18 and 25 mm to compare the heat input into the welds and to achieve the best results. The welds were characterised through microstructural evaluation, tensile testing, microhardness profiling, X-Ray Diffraction analysis, electrical resistivity and statistical analysis – in order to establish the interrelationship between the process parameters and the weld qualities. viii Microstructural evaluation of the weld samples revealed that the interfacial regions are characterised by mixture layers of aluminium and copper; while 33 percent of the tensile samples are within the acceptable range (> 75 percent joint efficiency). High Vickers microhardness values were measured at the joint interfaces, which corresponded with the intermetallic compounds. The Energy Dispersive Spectroscopy analysis revealed the presence of thin layers of intermetallics in nanoscale at the interfacial regions. The diffractograms of the X-Ray Diffraction analysis showed small peaks for intermetallics in some of the welds. Low electrical resistivities were measured at the joint interfaces. The statistical analysis showed that the downward vertical force, (Fz) can significantly influence the resulting weld qualities. An overall summary of the analysis of the weld qualities - with respect to the shoulder diameter tools employed showed that the 18 mm shoulder diameter tool is most appropriate among the three shoulder diameters considered, and a process window of medium spindle speed of 950 rpm and low-to-medium feed rate between 50 and 150 mm/min is established for FSW of Aluminium and Copper. Welds produced at 1200 rpm and 300 mm/min with low heat input did not have intermetallics formed at the joint interface.
- Full Text:
- Date Issued: 2010
The adoption of quality assurance in e-Health acquisition for rural hospitals in the Eastern Cape Province
- Authors: Ruxwana, Nkqubela
- Date: 2010
- Subjects: Quality assurance -- Management , Hospital care -- Quality control , Health facilities -- Quality control , Health -- Computer network resources , Public health -- Information services
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9731 , http://hdl.handle.net/10948/1514 , Quality assurance -- Management , Hospital care -- Quality control , Health facilities -- Quality control , Health -- Computer network resources , Public health -- Information services
- Description: The evolution of e-health has the potential to assist in the management of scarce resources and the shortage of skills, enhance efficiencies, improve quality and increase work productivity within the healthcare sector. As a result, an increase is seen in e-health solutions developments with the aim to improve healthcare services, hospital information systems, health decision support, telemedicine and other technical systems that have the potential to reduce cost, improve quality, and enhance the accessibility and delivery of healthcare. However, unfortunately their implementation contiues to fail. Although there are several reasons for this, in this study a lack of project quality management is viewed as a key contributor to the failure of e-health solutions implementation projects in rural hospitals. This results in neglected aspects of quality assurance (QA), which forms an integral part of project quality management. The purpose of this study is to develop a Genertic Quality Assurance Model (GQAM) for the successful acquisition (i.e. development and implementation) of e-health solutions in rural hospitals in the Eastern Cape Province to enable improved quality of care and service delivery. In order to develop and test this model it was necessary to identify the QA methodologies that are currently used in rural hospitals and to evaluate their strengths and weaknesses, as well as their impact on project success. The study is divided into four phases; in each phase different study designs were followed. The study used triangulation of qualitative and some elements of quantitative research approaches, in terms of which a case study approach was adpoted to answer the research questions. This study did indeed develop a GQAM that can be used to ensure e-health solution success in rural hospitals. Furthermore, to aid in the implementation of this model, a set of QA value chain implementation guidelines were developed, as a framework, to inject the nodel into typical (SDLC) phases.
- Full Text:
- Date Issued: 2010
- Authors: Ruxwana, Nkqubela
- Date: 2010
- Subjects: Quality assurance -- Management , Hospital care -- Quality control , Health facilities -- Quality control , Health -- Computer network resources , Public health -- Information services
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9731 , http://hdl.handle.net/10948/1514 , Quality assurance -- Management , Hospital care -- Quality control , Health facilities -- Quality control , Health -- Computer network resources , Public health -- Information services
- Description: The evolution of e-health has the potential to assist in the management of scarce resources and the shortage of skills, enhance efficiencies, improve quality and increase work productivity within the healthcare sector. As a result, an increase is seen in e-health solutions developments with the aim to improve healthcare services, hospital information systems, health decision support, telemedicine and other technical systems that have the potential to reduce cost, improve quality, and enhance the accessibility and delivery of healthcare. However, unfortunately their implementation contiues to fail. Although there are several reasons for this, in this study a lack of project quality management is viewed as a key contributor to the failure of e-health solutions implementation projects in rural hospitals. This results in neglected aspects of quality assurance (QA), which forms an integral part of project quality management. The purpose of this study is to develop a Genertic Quality Assurance Model (GQAM) for the successful acquisition (i.e. development and implementation) of e-health solutions in rural hospitals in the Eastern Cape Province to enable improved quality of care and service delivery. In order to develop and test this model it was necessary to identify the QA methodologies that are currently used in rural hospitals and to evaluate their strengths and weaknesses, as well as their impact on project success. The study is divided into four phases; in each phase different study designs were followed. The study used triangulation of qualitative and some elements of quantitative research approaches, in terms of which a case study approach was adpoted to answer the research questions. This study did indeed develop a GQAM that can be used to ensure e-health solution success in rural hospitals. Furthermore, to aid in the implementation of this model, a set of QA value chain implementation guidelines were developed, as a framework, to inject the nodel into typical (SDLC) phases.
- Full Text:
- Date Issued: 2010
Fostering information security culture through intergrating theory and technology
- Van Niekerk, Johannes Frederick
- Authors: Van Niekerk, Johannes Frederick
- Date: 2010
- Subjects: Information technology -- Security measures , Data protection , Corporate culture -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9754 , http://hdl.handle.net/10948/1404 , Information technology -- Security measures , Data protection , Corporate culture -- South Africa
- Description: Today information can be seen as a basic commodity that is crucial to the continuous well-being of modern organizations. Many modern organizations will be unable to do business without access to their information resources. It is therefor of vital importance for organizations to ensure that their infor- mation resources are adequately protected against both internal and external threats. This protection of information resources is known as information security and is, to a large extent, dependent on the behavior of humans in the organization. Humans, at various levels in the organization, play vital roles in the pro- cesses that secure organizational information resources. Many of the prob- lems experienced in information security can be directly contributed to the humans involved in the process. Employees, either intentionally or through negligence, often due to a lack of knowledge, can be seen as the greatest threat to information security. Addressing this human factor in information security is the primary focus of this thesis. The majority of current approaches to dealing with the human factors in information security acknowledge the need to foster an information security culture in the organization. However, very few current approaches attempt to adjust the "generic" model(s) used to define organizational culture to be specific to the needs of information security. This thesis firstly proposes, and argues, such an adapted conceptual model which aims to improve the understanding of what an information security culture is. The thesis secondly focuses on the underlying role that information security educational programs play in the fostering of an organizational information security culture. It is argued that many current information security edu- cational programs are not based on sound pedagogical theory. The use of learning taxonomies during the design of information security educational programs is proposed as a possible way to improve the pedagogical rigor of such programs. The thesis also argues in favor of the use of blended and/or e-learning approaches for the delivery of information security educational content. Finally, this thesis provides a detailed overview demonstrating how the various elements contributed by the thesis integrates into existing trans- formative change management processes for the fostering of an organizational information security culture.
- Full Text:
- Date Issued: 2010
- Authors: Van Niekerk, Johannes Frederick
- Date: 2010
- Subjects: Information technology -- Security measures , Data protection , Corporate culture -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9754 , http://hdl.handle.net/10948/1404 , Information technology -- Security measures , Data protection , Corporate culture -- South Africa
- Description: Today information can be seen as a basic commodity that is crucial to the continuous well-being of modern organizations. Many modern organizations will be unable to do business without access to their information resources. It is therefor of vital importance for organizations to ensure that their infor- mation resources are adequately protected against both internal and external threats. This protection of information resources is known as information security and is, to a large extent, dependent on the behavior of humans in the organization. Humans, at various levels in the organization, play vital roles in the pro- cesses that secure organizational information resources. Many of the prob- lems experienced in information security can be directly contributed to the humans involved in the process. Employees, either intentionally or through negligence, often due to a lack of knowledge, can be seen as the greatest threat to information security. Addressing this human factor in information security is the primary focus of this thesis. The majority of current approaches to dealing with the human factors in information security acknowledge the need to foster an information security culture in the organization. However, very few current approaches attempt to adjust the "generic" model(s) used to define organizational culture to be specific to the needs of information security. This thesis firstly proposes, and argues, such an adapted conceptual model which aims to improve the understanding of what an information security culture is. The thesis secondly focuses on the underlying role that information security educational programs play in the fostering of an organizational information security culture. It is argued that many current information security edu- cational programs are not based on sound pedagogical theory. The use of learning taxonomies during the design of information security educational programs is proposed as a possible way to improve the pedagogical rigor of such programs. The thesis also argues in favor of the use of blended and/or e-learning approaches for the delivery of information security educational content. Finally, this thesis provides a detailed overview demonstrating how the various elements contributed by the thesis integrates into existing trans- formative change management processes for the fostering of an organizational information security culture.
- Full Text:
- Date Issued: 2010
Developing an e-health framework through electronic healthcare readiness assessment
- Authors: Coleman, Alfred
- Date: 2010
- Subjects: Health -- Computer network resources , Medical care -- South Africa -- Computer network resources , Public health -- South Africa -- Computer network resources , Internet in medicine -- South Africa , Medical informatics -- South Africa , Telecommunication in medicine -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9729 , http://hdl.handle.net/10948/1519 , Health -- Computer network resources , Medical care -- South Africa -- Computer network resources , Public health -- South Africa -- Computer network resources , Internet in medicine -- South Africa , Medical informatics -- South Africa , Telecommunication in medicine -- South Africa
- Description: The major socio-economic development challenges facing most African countries include economic diversification, poverty, unemployment, diseases and the unsustainable use of natural resources. The challenge of quality healthcare provisioning is compounded by the HIV/AIDS pandemic in Sub Saharan Africa. However, there is a great potential in using electronic healthcare (e-health) as one of the supportive systems within the healthcare sector to address these pressing challenges facing healthcare systems in developing countries, including solving inequalities in healthcare delivery between rural and urban hospitals/clinics. The purpose of this study was to compile a Provincial E-health Framework (PEHF) based on the feedback from electronic healthcare readiness assessments conducted in selected rural and urban hospitals/clinics in the North West Province in South Africa. The e-healthcare readiness assessment was conducted in the light of effective use of ICT in patient healthcare record system, consultation among healthcare professionals, prescription of medication, referral of patients and training of healthcare professionals in ICT usage. The study was divided into two phases which were phases 1 and 2 and a qualitative design supported by a case study approach was used. Data were collected using different techniques to enhance triangulation of data. The techniques included group interviews, qualitative questionnaires, photographs, document analysis and expert opinions. The outcome of the assessment led to the compilation of the PEHF which was based on Service Oriented Architecture (SOA). SOA was chosen to integrate the hospitals/clinics‟ ICT infrastructure yet allowing each hospital/clinic the autonomy to control its own ICT environment. To assist hospitals/clinics integrate their ICT resources, this research study proposed an Infrastructure Network Architecture which clustered hospitals/clinics to share common ICT infrastructure instead of duplicating these resources. Furthermore, processes of the e-health services (e-patient health IV record system, e-consultation system, e-prescription system, e-referral system and e-training system) were provided to assist in the implementation of the PEHF. Finally, a set of guidelines were provided by the research study to aid the implementation of the PEHF.
- Full Text:
- Date Issued: 2010
- Authors: Coleman, Alfred
- Date: 2010
- Subjects: Health -- Computer network resources , Medical care -- South Africa -- Computer network resources , Public health -- South Africa -- Computer network resources , Internet in medicine -- South Africa , Medical informatics -- South Africa , Telecommunication in medicine -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9729 , http://hdl.handle.net/10948/1519 , Health -- Computer network resources , Medical care -- South Africa -- Computer network resources , Public health -- South Africa -- Computer network resources , Internet in medicine -- South Africa , Medical informatics -- South Africa , Telecommunication in medicine -- South Africa
- Description: The major socio-economic development challenges facing most African countries include economic diversification, poverty, unemployment, diseases and the unsustainable use of natural resources. The challenge of quality healthcare provisioning is compounded by the HIV/AIDS pandemic in Sub Saharan Africa. However, there is a great potential in using electronic healthcare (e-health) as one of the supportive systems within the healthcare sector to address these pressing challenges facing healthcare systems in developing countries, including solving inequalities in healthcare delivery between rural and urban hospitals/clinics. The purpose of this study was to compile a Provincial E-health Framework (PEHF) based on the feedback from electronic healthcare readiness assessments conducted in selected rural and urban hospitals/clinics in the North West Province in South Africa. The e-healthcare readiness assessment was conducted in the light of effective use of ICT in patient healthcare record system, consultation among healthcare professionals, prescription of medication, referral of patients and training of healthcare professionals in ICT usage. The study was divided into two phases which were phases 1 and 2 and a qualitative design supported by a case study approach was used. Data were collected using different techniques to enhance triangulation of data. The techniques included group interviews, qualitative questionnaires, photographs, document analysis and expert opinions. The outcome of the assessment led to the compilation of the PEHF which was based on Service Oriented Architecture (SOA). SOA was chosen to integrate the hospitals/clinics‟ ICT infrastructure yet allowing each hospital/clinic the autonomy to control its own ICT environment. To assist hospitals/clinics integrate their ICT resources, this research study proposed an Infrastructure Network Architecture which clustered hospitals/clinics to share common ICT infrastructure instead of duplicating these resources. Furthermore, processes of the e-health services (e-patient health IV record system, e-consultation system, e-prescription system, e-referral system and e-training system) were provided to assist in the implementation of the PEHF. Finally, a set of guidelines were provided by the research study to aid the implementation of the PEHF.
- Full Text:
- Date Issued: 2010
The possibility of a flexible wireless 3-D measurement in the modern automobile production
- Authors: Frede, Stefan
- Date: 2010
- Subjects: Three-dimensional display systems , Automobile industry and trade , Automobile industry and trade -- South Africa -- Quality control
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9619 , http://hdl.handle.net/10948/1203 , Three-dimensional display systems , Automobile industry and trade , Automobile industry and trade -- South Africa -- Quality control
- Description: The quality control of geometrical coherences and relations in modern automobile production is done by different stationary and flexible measurement systems and strategies. Furthermore, there currently exists possibilities of inline measurements and offline measurements. This project presents the basic research concerning the possibility of a flexible wireless measurement system in modern automobile production, that is able to combine the advantages of both strategies. An investigation of existing measurement techniques was done in order to find a sensor technology, which enables the wireless measurement process. The research project introduces the current location systems and positioning systems. These techniques are compared by a value benefit analysis to expose a suited technology as basis for the measurement system. As result of the value benefit anlysis, the ultrasonic technique was selected for further investigations. The ultrasonic test setup is used to analyze the accuracy of modern sensors and to verify the possibility of a project related integration. The tests are done in different conditions, in order to compare the laboratory application and the industrial application. During the test measurements different physical influencing variables and disturbances occurred. From this research project, it can be concluded that the laboratory application of the system is possible. However, the industrial application is subject to restrictions.
- Full Text:
- Date Issued: 2010
- Authors: Frede, Stefan
- Date: 2010
- Subjects: Three-dimensional display systems , Automobile industry and trade , Automobile industry and trade -- South Africa -- Quality control
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9619 , http://hdl.handle.net/10948/1203 , Three-dimensional display systems , Automobile industry and trade , Automobile industry and trade -- South Africa -- Quality control
- Description: The quality control of geometrical coherences and relations in modern automobile production is done by different stationary and flexible measurement systems and strategies. Furthermore, there currently exists possibilities of inline measurements and offline measurements. This project presents the basic research concerning the possibility of a flexible wireless measurement system in modern automobile production, that is able to combine the advantages of both strategies. An investigation of existing measurement techniques was done in order to find a sensor technology, which enables the wireless measurement process. The research project introduces the current location systems and positioning systems. These techniques are compared by a value benefit analysis to expose a suited technology as basis for the measurement system. As result of the value benefit anlysis, the ultrasonic technique was selected for further investigations. The ultrasonic test setup is used to analyze the accuracy of modern sensors and to verify the possibility of a project related integration. The tests are done in different conditions, in order to compare the laboratory application and the industrial application. During the test measurements different physical influencing variables and disturbances occurred. From this research project, it can be concluded that the laboratory application of the system is possible. However, the industrial application is subject to restrictions.
- Full Text:
- Date Issued: 2010
Constraints and challenges faced by small, medium and micro enterprise contractors in Malawi
- Authors: Chilipunde, Rodrick Lengama
- Date: 2010
- Subjects: Small business -- Malawi -- Management , Contractors' operations -- Malawi , Small business -- Malawi -- Finance
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9686 , http://hdl.handle.net/10948/1220 , Small business -- Malawi -- Management , Contractors' operations -- Malawi , Small business -- Malawi -- Finance
- Description: Small, medium and micro enterprises (SMMEs) are an important sector of any construction economy. The need for efficient SMMEs is well documented and cannot be over-emphasised. SMMEs are vital in their contribution to employment creation and value reorientation. However, their in process operations are not well understood and have rarely been addressed. The aim of this research was therefore to establish a base level of understanding of the operational core-face of SMMEs in Malawi. The methodology used included an extensive literature review and field survey conducted on 52 SMMEs. The field survey used the questionnaire instrument and random sampling. The critical findings from the literature were that there are binding constraints in the operations of SMMEs. The field survey confirmed the issues raised in the literature and posited the operational challenges as lack of finance, training and business skills; limited skills in Construction Information Technology (IT), and prevalence of unethical conduct amongst some of the stakeholders. The findings make an invaluable contribution to the search for solutions to the problems faced by construction SMMEs in Malawi and provide insight for further research in institutional weaknesses and policy issues regarding in this part of the world. The implications of the findings are that unless the limitations named above are resolved, SMMEs in Malawi will continue to experience poor growth and competitiveness. The recommendations include the developing of training programmes in business management, introduction of sector specific financing programmes and the provision of an appropriate regulatory and legislative framework. By establishing the core issues affecting the operations of SMMEs in the Malawian construction industry, the research has contributed to the enhancement of the understanding of this elusive subject.
- Full Text:
- Date Issued: 2010
- Authors: Chilipunde, Rodrick Lengama
- Date: 2010
- Subjects: Small business -- Malawi -- Management , Contractors' operations -- Malawi , Small business -- Malawi -- Finance
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9686 , http://hdl.handle.net/10948/1220 , Small business -- Malawi -- Management , Contractors' operations -- Malawi , Small business -- Malawi -- Finance
- Description: Small, medium and micro enterprises (SMMEs) are an important sector of any construction economy. The need for efficient SMMEs is well documented and cannot be over-emphasised. SMMEs are vital in their contribution to employment creation and value reorientation. However, their in process operations are not well understood and have rarely been addressed. The aim of this research was therefore to establish a base level of understanding of the operational core-face of SMMEs in Malawi. The methodology used included an extensive literature review and field survey conducted on 52 SMMEs. The field survey used the questionnaire instrument and random sampling. The critical findings from the literature were that there are binding constraints in the operations of SMMEs. The field survey confirmed the issues raised in the literature and posited the operational challenges as lack of finance, training and business skills; limited skills in Construction Information Technology (IT), and prevalence of unethical conduct amongst some of the stakeholders. The findings make an invaluable contribution to the search for solutions to the problems faced by construction SMMEs in Malawi and provide insight for further research in institutional weaknesses and policy issues regarding in this part of the world. The implications of the findings are that unless the limitations named above are resolved, SMMEs in Malawi will continue to experience poor growth and competitiveness. The recommendations include the developing of training programmes in business management, introduction of sector specific financing programmes and the provision of an appropriate regulatory and legislative framework. By establishing the core issues affecting the operations of SMMEs in the Malawian construction industry, the research has contributed to the enhancement of the understanding of this elusive subject.
- Full Text:
- Date Issued: 2010
Laser surface hardening of AISI 1518 alloy steel
- Authors: Zhang, Tao
- Date: 2010
- Subjects: Lasers , Laser beams , Lasers in engineering , Nd-YAG lasers , Steel alloys , Surfaces -- Effect of radiation on
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9613 , http://hdl.handle.net/10948/723 , Lasers , Laser beams , Lasers in engineering , Nd-YAG lasers , Steel alloys , Surfaces -- Effect of radiation on
- Description: The laser surface hardening process will enhance the hardness profile of automotive components and ensure better process control and predictability of quality as compared to the conventional hardening processes. A 2KW Nd-YAG laser system was used to harden the surface of alloy steel with various process parameters (laser power, focal spot diameter and beam velocity). The results (microhardness, microstructure change and residual stress distribution) were measured and analyzed with Vickers microhardness tester, optical/electron microscope and hole-drilling residual stress equipment. Statistical analyses of the experimental data were used for explaining the relationships between process parameters, microhardness and microstructure. General thermal hardening was applied in the research to show the influence of heating temperature and cooling method on microstructure and mechanical properties. Also, the results were compared with laser surface hardening process from microhardness, microstructure and residual stress to show the advantage of laser surface hardening. Through analysis of the results of the laser surface hardening experiments, a suitable laser power density and interaction time for optimum hardening was obtained. The presented laser surface hardening process can also be applied to other alloy steel surface hardening process.
- Full Text:
- Date Issued: 2010
- Authors: Zhang, Tao
- Date: 2010
- Subjects: Lasers , Laser beams , Lasers in engineering , Nd-YAG lasers , Steel alloys , Surfaces -- Effect of radiation on
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9613 , http://hdl.handle.net/10948/723 , Lasers , Laser beams , Lasers in engineering , Nd-YAG lasers , Steel alloys , Surfaces -- Effect of radiation on
- Description: The laser surface hardening process will enhance the hardness profile of automotive components and ensure better process control and predictability of quality as compared to the conventional hardening processes. A 2KW Nd-YAG laser system was used to harden the surface of alloy steel with various process parameters (laser power, focal spot diameter and beam velocity). The results (microhardness, microstructure change and residual stress distribution) were measured and analyzed with Vickers microhardness tester, optical/electron microscope and hole-drilling residual stress equipment. Statistical analyses of the experimental data were used for explaining the relationships between process parameters, microhardness and microstructure. General thermal hardening was applied in the research to show the influence of heating temperature and cooling method on microstructure and mechanical properties. Also, the results were compared with laser surface hardening process from microhardness, microstructure and residual stress to show the advantage of laser surface hardening. Through analysis of the results of the laser surface hardening experiments, a suitable laser power density and interaction time for optimum hardening was obtained. The presented laser surface hardening process can also be applied to other alloy steel surface hardening process.
- Full Text:
- Date Issued: 2010
The effects of hyperinflation on the Zimbabwean construction industry
- Authors: Moyo, Admire
- Date: 2010
- Subjects: Inflation (Finance) -- Zimbabwe , Zimbabwe -- Economic conditions , Construction industry -- Economic aspects -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9687 , http://hdl.handle.net/10948/1197 , Inflation (Finance) -- Zimbabwe , Zimbabwe -- Economic conditions , Construction industry -- Economic aspects -- Zimbabwe
- Description: Less than two decades ago, Zimbabwe was a symbol for the rest of the world of what Africa could become (Dell, 2005). DiSilvio (2007) contends that independent Zimbabwe was an economic success on route to attaining status of the most “developed country” in Africa. Contrary to expectations, by 2003 the Zimbabwean economy was shrinking faster than any other economy in the world at 18 percent per year (Richardson, 2005). Reports indicate that the Zimbabwean economy is in crisis and has since been set back by more than 50 years (Matikinye, 2005). This phenomenon necessitated the need for an investigation to ascertain its cause in Zimbabwe. As a result, the research identifies and presents hyperinflation as the root cause of the crisis in Zimbabwe and illustrates the validity of this assertion with a focus on the Zimbabwean construction industry. As part of the research inquiry, a review of related literature was conducted. The literature review illustrated the generic effects of hyperinflation as well as the effects of this phenomenon in action in Zimbabwe. The literature study was followed by a questionnaire survey. The questionnaire was completed by 23 contractors and 7 clients from a census of contractors and clients in Zimbabwe. The questionnaire consisted of a number of variables, which the respondents were asked to rate vis-à-vis the effects of hyperinflation in the construction industry. In summary, the questionnaire sought to determine the causes of hyperinflation in Zimbabwe, its specific effects on the construction industry and how respondents thought the phenomenon could be mitigated so as to revive the Zimbabwean construction industry. The techniques of re-scaling, in conjunction with descriptive and inferential statistics, ranking and quadrant analysis were applied to the data. Results from these analyses revealed a high degree of agreement among respondents vis-à-vis the effects of hyperinflation on the Zimbabwean construction industry. The interpretation of the results further revealed that hyperinflation has undoubtedly led to the collapse of the Zimbabwean construction industry. In conclusion, the research, applying the interpretations of v the survey findings, prescribes a number of ways in which the Zimbabwean construction sector may be resurrected. Among the recommended prescriptions, there are a number of debatable issues that arise that the researcher proposes should be subject to future study.
- Full Text:
- Date Issued: 2010
- Authors: Moyo, Admire
- Date: 2010
- Subjects: Inflation (Finance) -- Zimbabwe , Zimbabwe -- Economic conditions , Construction industry -- Economic aspects -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9687 , http://hdl.handle.net/10948/1197 , Inflation (Finance) -- Zimbabwe , Zimbabwe -- Economic conditions , Construction industry -- Economic aspects -- Zimbabwe
- Description: Less than two decades ago, Zimbabwe was a symbol for the rest of the world of what Africa could become (Dell, 2005). DiSilvio (2007) contends that independent Zimbabwe was an economic success on route to attaining status of the most “developed country” in Africa. Contrary to expectations, by 2003 the Zimbabwean economy was shrinking faster than any other economy in the world at 18 percent per year (Richardson, 2005). Reports indicate that the Zimbabwean economy is in crisis and has since been set back by more than 50 years (Matikinye, 2005). This phenomenon necessitated the need for an investigation to ascertain its cause in Zimbabwe. As a result, the research identifies and presents hyperinflation as the root cause of the crisis in Zimbabwe and illustrates the validity of this assertion with a focus on the Zimbabwean construction industry. As part of the research inquiry, a review of related literature was conducted. The literature review illustrated the generic effects of hyperinflation as well as the effects of this phenomenon in action in Zimbabwe. The literature study was followed by a questionnaire survey. The questionnaire was completed by 23 contractors and 7 clients from a census of contractors and clients in Zimbabwe. The questionnaire consisted of a number of variables, which the respondents were asked to rate vis-à-vis the effects of hyperinflation in the construction industry. In summary, the questionnaire sought to determine the causes of hyperinflation in Zimbabwe, its specific effects on the construction industry and how respondents thought the phenomenon could be mitigated so as to revive the Zimbabwean construction industry. The techniques of re-scaling, in conjunction with descriptive and inferential statistics, ranking and quadrant analysis were applied to the data. Results from these analyses revealed a high degree of agreement among respondents vis-à-vis the effects of hyperinflation on the Zimbabwean construction industry. The interpretation of the results further revealed that hyperinflation has undoubtedly led to the collapse of the Zimbabwean construction industry. In conclusion, the research, applying the interpretations of v the survey findings, prescribes a number of ways in which the Zimbabwean construction sector may be resurrected. Among the recommended prescriptions, there are a number of debatable issues that arise that the researcher proposes should be subject to future study.
- Full Text:
- Date Issued: 2010
Effective management of machinery in government-operated hospitals
- Authors: Gatang'i, Peter Gatheru
- Date: 2010
- Subjects: Machinery -- Maintenance and repair , Plant maintenance -- Management , Hospitals -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9664 , http://hdl.handle.net/10948/1237 , Machinery -- Maintenance and repair , Plant maintenance -- Management , Hospitals -- South Africa -- Eastern Cape
- Description: The methodology and the processes that are followed in the maintenance of government-operated district hospitals in the Eastern Cape Province of South Africa are outlined while the strategies that are employed to roll-out the maintenance plan have been investigated. The challenges in managing hospital maintenance are identified so that it can be improved and advice be given on the strategies currently being used. The objectives of the research were to determine the effectiveness of machinery maintenance in government-operated district hospitals. The study has been carried out by investigating 50 district hospitals within the Eastern Cape Province, with the aim of obtaining knowledge of practices in relation to the strategic plans and best practices in the maintenance industry. The following factors identified by the maintenance staff were found to be most important in maintenance management practices; realistic budgets, adherence to occupational health and safety regulations, engagement of qualified and skilled maintenance staff, good record management in relation to the equipment under maintenance, availability of tools and materials and keeping abreast with the latest technologies and trends of machinery advancement. The study also revealed that the majority of the hospitals use a combination of in-house and outsourced personnel during maintenance, the outsourced part being under contract from the National Department of Public Works Repair and Maintenance Plan (RAMP) projects. Service kits and recommended replacement parts for machinery are rarely stocked on the hospital premises while only minor spare parts that include replacement bulbs, electrical fittings, plumbing fittings and paint are readily available. In addition, the maintenance staff members have little or no input in maintenance budgeting, this aspect is controlled by hospital management. For maintenance to be effective, strategic planning that takes into account carefully thought-out maintenance management systems is the first step in the direction of setting out definite tangible objectives and goals. The real challenge lies in the implementation and sustainability of the maintenance management system and the monitoring thereof.
- Full Text:
- Date Issued: 2010
- Authors: Gatang'i, Peter Gatheru
- Date: 2010
- Subjects: Machinery -- Maintenance and repair , Plant maintenance -- Management , Hospitals -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9664 , http://hdl.handle.net/10948/1237 , Machinery -- Maintenance and repair , Plant maintenance -- Management , Hospitals -- South Africa -- Eastern Cape
- Description: The methodology and the processes that are followed in the maintenance of government-operated district hospitals in the Eastern Cape Province of South Africa are outlined while the strategies that are employed to roll-out the maintenance plan have been investigated. The challenges in managing hospital maintenance are identified so that it can be improved and advice be given on the strategies currently being used. The objectives of the research were to determine the effectiveness of machinery maintenance in government-operated district hospitals. The study has been carried out by investigating 50 district hospitals within the Eastern Cape Province, with the aim of obtaining knowledge of practices in relation to the strategic plans and best practices in the maintenance industry. The following factors identified by the maintenance staff were found to be most important in maintenance management practices; realistic budgets, adherence to occupational health and safety regulations, engagement of qualified and skilled maintenance staff, good record management in relation to the equipment under maintenance, availability of tools and materials and keeping abreast with the latest technologies and trends of machinery advancement. The study also revealed that the majority of the hospitals use a combination of in-house and outsourced personnel during maintenance, the outsourced part being under contract from the National Department of Public Works Repair and Maintenance Plan (RAMP) projects. Service kits and recommended replacement parts for machinery are rarely stocked on the hospital premises while only minor spare parts that include replacement bulbs, electrical fittings, plumbing fittings and paint are readily available. In addition, the maintenance staff members have little or no input in maintenance budgeting, this aspect is controlled by hospital management. For maintenance to be effective, strategic planning that takes into account carefully thought-out maintenance management systems is the first step in the direction of setting out definite tangible objectives and goals. The real challenge lies in the implementation and sustainability of the maintenance management system and the monitoring thereof.
- Full Text:
- Date Issued: 2010
Influences on construction project delivery time
- Authors: Olatunji, Aiyetan Ayodeji
- Date: 2010
- Subjects: Construction industry -- South Africa -- Management , Project management -- South Africa , Construction industry -- Economic aspects -- South Africa , Construction industry -- Technological innovations -- South Africa , Construction industry -- Labor productivity -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9681 , http://hdl.handle.net/10948/1548 , Construction industry -- South Africa -- Management , Project management -- South Africa , Construction industry -- Economic aspects -- South Africa , Construction industry -- Technological innovations -- South Africa , Construction industry -- Labor productivity -- South Africa
- Description: Construction delays are a global phenomenon. Factors causing construction delays in construction projects differ from country to country, due to different prevailing conditions. The prevailing conditions that could exert an influence on project delivery time are: political, economic, and physical factors as well as level of technological development; management style, and construction techniques. The construction industry is a major player in the economy, generating both employment and wealth. However, many projects experience extensive delays and thereby exceed initial time and cost estimates. This study aims at determining the causes of delays in project delivery in South Africa; evolving interventions, and developing a model for the delivery of projects on time. Inferential and linear regression statistical tools were used in the analysis of data for the study. The sample population consists of architects, builders, quantity surveyors, structural engineers, and clients, and the metropolitan cities of five provinces constituted the geographical delimitation of the study. The provinces are: Eastern Cape; Free State; Gauteng; KwaZulu-Natal, and Western Cape. The metropolitan cities are: Bloemfontein; Cape Town; Durban; Johannesburg, and Port Elizabeth. Findings which negatively influence project delivery time in South Africa include the following: lack of adequate planning; management style; the lack of constructability reviews of designs; inadequate motivation of workers; economic policies; lack of prompt payment to contractors, and quality of management during design and construction. Recommendations include: (1) The introduction of the following courses in built environment tertiary education � quality management competences; operational planning; design management, and generic management; (2) pre-qualification of suppliers; (3) inclusion of the following in tender documentation � human resource schedule; plant and equipment schedule; quality assurance plan, and work schedule; (4) appointment of materials specialists on a large projects; (5) the model developed should be adopted for use in the South African construction industry for the delivery of projects on time, and (6) the linear regression equation: Y = 13.1159 + 1.1341x or 35.3 percent addition on time for the estimation of project delivery time.
- Full Text:
- Date Issued: 2010
- Authors: Olatunji, Aiyetan Ayodeji
- Date: 2010
- Subjects: Construction industry -- South Africa -- Management , Project management -- South Africa , Construction industry -- Economic aspects -- South Africa , Construction industry -- Technological innovations -- South Africa , Construction industry -- Labor productivity -- South Africa
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:9681 , http://hdl.handle.net/10948/1548 , Construction industry -- South Africa -- Management , Project management -- South Africa , Construction industry -- Economic aspects -- South Africa , Construction industry -- Technological innovations -- South Africa , Construction industry -- Labor productivity -- South Africa
- Description: Construction delays are a global phenomenon. Factors causing construction delays in construction projects differ from country to country, due to different prevailing conditions. The prevailing conditions that could exert an influence on project delivery time are: political, economic, and physical factors as well as level of technological development; management style, and construction techniques. The construction industry is a major player in the economy, generating both employment and wealth. However, many projects experience extensive delays and thereby exceed initial time and cost estimates. This study aims at determining the causes of delays in project delivery in South Africa; evolving interventions, and developing a model for the delivery of projects on time. Inferential and linear regression statistical tools were used in the analysis of data for the study. The sample population consists of architects, builders, quantity surveyors, structural engineers, and clients, and the metropolitan cities of five provinces constituted the geographical delimitation of the study. The provinces are: Eastern Cape; Free State; Gauteng; KwaZulu-Natal, and Western Cape. The metropolitan cities are: Bloemfontein; Cape Town; Durban; Johannesburg, and Port Elizabeth. Findings which negatively influence project delivery time in South Africa include the following: lack of adequate planning; management style; the lack of constructability reviews of designs; inadequate motivation of workers; economic policies; lack of prompt payment to contractors, and quality of management during design and construction. Recommendations include: (1) The introduction of the following courses in built environment tertiary education � quality management competences; operational planning; design management, and generic management; (2) pre-qualification of suppliers; (3) inclusion of the following in tender documentation � human resource schedule; plant and equipment schedule; quality assurance plan, and work schedule; (4) appointment of materials specialists on a large projects; (5) the model developed should be adopted for use in the South African construction industry for the delivery of projects on time, and (6) the linear regression equation: Y = 13.1159 + 1.1341x or 35.3 percent addition on time for the estimation of project delivery time.
- Full Text:
- Date Issued: 2010
C3TO : a scalable architecture for mobile chat based tutoring
- Authors: Butgereit, Laura Lee
- Date: 2010
- Subjects: Intelligent tutoring systems , Instructional systems -- Design
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9746 , http://hdl.handle.net/10948/1511 , Intelligent tutoring systems , Instructional systems -- Design
- Description: C³TO (Chatter Call Centre/Tutoring Online) is a scalable architecture to support mobile online tutoring using chat protocols over cell phones. It is the scalability of this architecture which is the primary focus of this dissertation. Much has been written lamenting the state of mathematics education in South Africa. It is not a pretty story. In order to help solve this mathematical crisis, the “Dr Math” research project was started in January, 2007. “Dr Math” strove to assist school pupils with their mathematics homework by providing access to tutors from a nearby university to help them. The school pupils used MXit on their cell phones and the tutors used normal computer workstations. The original “Dr Math” research project expected no more than twenty to thirty school pupils to participate. Unexpectedly thousands of school pupils started asking “Dr Math” to assist them with their mathematics homework. The original software could not scale. The original software could not cater for the thousands of pupils needing help. The scalability problems which existed in the original “Dr Math” project included: hardware scalability issues, software scalability problems, lack of physical office space for tutors, and tutor time being wasted by trivial questions. C³TO tackled these scalability concerns using an innovative three level approach by implementing a technological feature level, a tactical feature level, and a strategic feature level in the C³TO architecture. The technological level included specific components, utilities, and platforms which promoted scalability. The technological level provided the basic building blocks with which to construct a scalable architecture. The tactical level arranged the basic building blocks of the technological level into a scalable architecture. The tactical level provided short term solutions to scalability concerns by providing easy configurability and decision making. The strategic level attempted to answer the pupils questions before they actually arrived at the tutor thereby reducing the load on the human tutors. C³TO was extensively tested and evaluated. C³TO supported thousands of school pupils with their mathematics homework over a period of ten months. C³TO was used to support a small conference. C³TO was used to encourage people to volunteer their time in participation of Mandela Day. C³TO was used to support “Winter School” during the winter school holiday. In all these cases, C³TO proved itself to be scalable.
- Full Text:
- Date Issued: 2010
- Authors: Butgereit, Laura Lee
- Date: 2010
- Subjects: Intelligent tutoring systems , Instructional systems -- Design
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9746 , http://hdl.handle.net/10948/1511 , Intelligent tutoring systems , Instructional systems -- Design
- Description: C³TO (Chatter Call Centre/Tutoring Online) is a scalable architecture to support mobile online tutoring using chat protocols over cell phones. It is the scalability of this architecture which is the primary focus of this dissertation. Much has been written lamenting the state of mathematics education in South Africa. It is not a pretty story. In order to help solve this mathematical crisis, the “Dr Math” research project was started in January, 2007. “Dr Math” strove to assist school pupils with their mathematics homework by providing access to tutors from a nearby university to help them. The school pupils used MXit on their cell phones and the tutors used normal computer workstations. The original “Dr Math” research project expected no more than twenty to thirty school pupils to participate. Unexpectedly thousands of school pupils started asking “Dr Math” to assist them with their mathematics homework. The original software could not scale. The original software could not cater for the thousands of pupils needing help. The scalability problems which existed in the original “Dr Math” project included: hardware scalability issues, software scalability problems, lack of physical office space for tutors, and tutor time being wasted by trivial questions. C³TO tackled these scalability concerns using an innovative three level approach by implementing a technological feature level, a tactical feature level, and a strategic feature level in the C³TO architecture. The technological level included specific components, utilities, and platforms which promoted scalability. The technological level provided the basic building blocks with which to construct a scalable architecture. The tactical level arranged the basic building blocks of the technological level into a scalable architecture. The tactical level provided short term solutions to scalability concerns by providing easy configurability and decision making. The strategic level attempted to answer the pupils questions before they actually arrived at the tutor thereby reducing the load on the human tutors. C³TO was extensively tested and evaluated. C³TO supported thousands of school pupils with their mathematics homework over a period of ten months. C³TO was used to support a small conference. C³TO was used to encourage people to volunteer their time in participation of Mandela Day. C³TO was used to support “Winter School” during the winter school holiday. In all these cases, C³TO proved itself to be scalable.
- Full Text:
- Date Issued: 2010
Process window for friction stir welding of 3 mm titanium (Ti-6AI-4V)
- Authors: Mashinini, Peter Madindwa
- Date: 2010
- Subjects: Friction stir welding , Titanium -- Welding , Welded joints
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9618 , http://hdl.handle.net/10948/1413 , Friction stir welding , Titanium -- Welding , Welded joints
- Description: Friction stir welding was used to join 3 mm Ti-6Al-4V alloy in a butt joint configuration. This research focused on optimization of a tool geometry and the interaction between process parameters and static performance of welded joints. The main parameters varied were tool travel speed and tool rotational speed. The results showed a relationship between heat input as a function of process parameters and static strength. Improved tensile properties correspond to high heat input. The hardness plots revealed an increase in hardness on both the stir zone and heat affected zone despite the small defects on the weld root. The weld microstructure was also evaluated, which showed a variation in microstructure on both the heat affected zone and stir zone in comparison to the parent material. It was also found that the use of MgO as a heat barrier on the backing plate was detrimental to the weld tensile properties of butt-welded plates compared to bead-on-plate welds of which MgO had no influence.
- Full Text:
- Date Issued: 2010
- Authors: Mashinini, Peter Madindwa
- Date: 2010
- Subjects: Friction stir welding , Titanium -- Welding , Welded joints
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9618 , http://hdl.handle.net/10948/1413 , Friction stir welding , Titanium -- Welding , Welded joints
- Description: Friction stir welding was used to join 3 mm Ti-6Al-4V alloy in a butt joint configuration. This research focused on optimization of a tool geometry and the interaction between process parameters and static performance of welded joints. The main parameters varied were tool travel speed and tool rotational speed. The results showed a relationship between heat input as a function of process parameters and static strength. Improved tensile properties correspond to high heat input. The hardness plots revealed an increase in hardness on both the stir zone and heat affected zone despite the small defects on the weld root. The weld microstructure was also evaluated, which showed a variation in microstructure on both the heat affected zone and stir zone in comparison to the parent material. It was also found that the use of MgO as a heat barrier on the backing plate was detrimental to the weld tensile properties of butt-welded plates compared to bead-on-plate welds of which MgO had no influence.
- Full Text:
- Date Issued: 2010
An evaluation of the impact of corruption, economic status and political influence on the Malawian construction industry
- Authors: Phiri, Mulima Anaclet
- Date: 2010
- Subjects: Construction industry -- Malawi
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9688 , http://hdl.handle.net/10948/1155 , Construction industry -- Malawi
- Description: The key objectives of this MSc (Construction Management) dissertation are to evaluate the negative impact of: corruption; political influence, and the poor economy on the construction industry; in order to gain insight regarding the management of the sector to achieve the desired project deliverables, which are: • Achievement of a functional fit for purpose built environment, which is to the clients’ requirements; • Achievement of a Financially viable product in line with the clients’ budget; • Achievement of a successful and timely completion, and • Achievement of the required quality standard of the final product. To achieve the above mentioned project deliverables, the study entailed the following prominent findings: • There is a need to manage political greed in the distribution of development projects, and functionality of the product to suit the client / community; • There is a need to manage, mitigate and combat corruption in order to diminish the dominance of unscrupulous contractors over others, and to achieve clients’ desired quality standards; • There is a requirement to manage the construction policy formulation process and governance of laws and regulations to revamp the retrogression of the industry, and • There is a requirement to manage project cost to significantly boost the ailing economy. In conclusion, the study evaluates the Malawi construction industry status and improvements there on. The management of the industry’s phenomena and mind set is of paramount importance to the success of the findings in this study. Recommendations to improve the status quo relative to the findings are: to train all active stakeholders in construction management courses; a national initiative to sensitise the community regarding the powers granted to them, as an electorate of the stakeholders; to change the phenomenon of and mindset relative to bribes, and finally to derive a passion for construction and for the associated built environment.
- Full Text:
- Date Issued: 2010
- Authors: Phiri, Mulima Anaclet
- Date: 2010
- Subjects: Construction industry -- Malawi
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9688 , http://hdl.handle.net/10948/1155 , Construction industry -- Malawi
- Description: The key objectives of this MSc (Construction Management) dissertation are to evaluate the negative impact of: corruption; political influence, and the poor economy on the construction industry; in order to gain insight regarding the management of the sector to achieve the desired project deliverables, which are: • Achievement of a functional fit for purpose built environment, which is to the clients’ requirements; • Achievement of a Financially viable product in line with the clients’ budget; • Achievement of a successful and timely completion, and • Achievement of the required quality standard of the final product. To achieve the above mentioned project deliverables, the study entailed the following prominent findings: • There is a need to manage political greed in the distribution of development projects, and functionality of the product to suit the client / community; • There is a need to manage, mitigate and combat corruption in order to diminish the dominance of unscrupulous contractors over others, and to achieve clients’ desired quality standards; • There is a requirement to manage the construction policy formulation process and governance of laws and regulations to revamp the retrogression of the industry, and • There is a requirement to manage project cost to significantly boost the ailing economy. In conclusion, the study evaluates the Malawi construction industry status and improvements there on. The management of the industry’s phenomena and mind set is of paramount importance to the success of the findings in this study. Recommendations to improve the status quo relative to the findings are: to train all active stakeholders in construction management courses; a national initiative to sensitise the community regarding the powers granted to them, as an electorate of the stakeholders; to change the phenomenon of and mindset relative to bribes, and finally to derive a passion for construction and for the associated built environment.
- Full Text:
- Date Issued: 2010
Modelling and control of combustion in a high velocity air flame (HVAF) thermal spraying process
- Authors: Barth, Dominic
- Date: 2010
- Subjects: Metal spraying , Combustion
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9644 , http://hdl.handle.net/10948/1266 , Metal spraying , Combustion
- Description: Thermal spraying is a technology, which is used for coating of components and structures in order to achieve certain tribological characteristics, or for protection against corrosion, excessive temperature and wear. Within thermal spray, there are processes, which utilise combustion of liquid fuel to obtain high velocities flows providing, therefore, good adhesion of coating materials to substrates. These include High Velocity Oxygen Flame (HVOF) and High Velocity Air Flame (HVAF) process, of which the former one is widely used as it has been developed for at least two decades, while HVAF is less common. However, some studies indicate that HVAF has a number of advantages over HVOF, including the economic benefits. The thermal spray gun, based on the HVAF process, has been developed before, but the system was controlled manually. Therefore, there is a need to develop a fully automated controller of an HVAF thermal spray system. Process control of thermal spraying is highly complex as it involves simultaneous control of a number of processes, including; ignition process, combustion process, spraying material melting, as well as control and monitoring of auxiliary equipment. This paper presents the development of a control system for an HVAF thermal spray system, based on a Microchip PIC microcontroller. The designed control system was applied for controlling of thermal spraying of carbides powders, and provided a reliable ignition and stable combustion process, powder feeding and all other functions of control.
- Full Text:
- Date Issued: 2010
- Authors: Barth, Dominic
- Date: 2010
- Subjects: Metal spraying , Combustion
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9644 , http://hdl.handle.net/10948/1266 , Metal spraying , Combustion
- Description: Thermal spraying is a technology, which is used for coating of components and structures in order to achieve certain tribological characteristics, or for protection against corrosion, excessive temperature and wear. Within thermal spray, there are processes, which utilise combustion of liquid fuel to obtain high velocities flows providing, therefore, good adhesion of coating materials to substrates. These include High Velocity Oxygen Flame (HVOF) and High Velocity Air Flame (HVAF) process, of which the former one is widely used as it has been developed for at least two decades, while HVAF is less common. However, some studies indicate that HVAF has a number of advantages over HVOF, including the economic benefits. The thermal spray gun, based on the HVAF process, has been developed before, but the system was controlled manually. Therefore, there is a need to develop a fully automated controller of an HVAF thermal spray system. Process control of thermal spraying is highly complex as it involves simultaneous control of a number of processes, including; ignition process, combustion process, spraying material melting, as well as control and monitoring of auxiliary equipment. This paper presents the development of a control system for an HVAF thermal spray system, based on a Microchip PIC microcontroller. The designed control system was applied for controlling of thermal spraying of carbides powders, and provided a reliable ignition and stable combustion process, powder feeding and all other functions of control.
- Full Text:
- Date Issued: 2010
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