Performance improvement in South African construction
- Authors: Emuze, Fidelis Abumere
- Date: 2011
- Subjects: Construction industry -- South Africa -- Management , Project management -- South Africa , Construction projects -- Management , Business logistics -- South Africa -- Management
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9678 , http://hdl.handle.net/10948/1642 , Construction industry -- South Africa -- Management , Project management -- South Africa , Construction projects -- Management , Business logistics -- South Africa -- Management
- Description: In general, dreams are conceived, ideas are conceptualised, and initiatives are embarked upon in order to alter the state of realities. Dreams change realities; when mechanisms are put in place to realise them, dreams succeed. However, anecdotal evidence as well as empirical findings has continued to reiterate the difficulties associated with realising dreams related to construction projects. Extending the „dream‟ analogy to the South African construction industry context therefore paints an uninspiring picture. Dreams associated with construction do not have a 100% chance of becoming realities as evident in reported poor project performance in the industry. Shattered dreams in the form of poor performing projects, poorly implemented construction processes, or worst, projects delivered at the expense of unexpected cost to the client as a direct result of poor H&S or time overruns, negate the intent of dreams. This thesis is primarily concerned with project performance related bottlenecks in South African construction. After an extensive review of related literature that entails the analysis of publications related to non-value adding activities (NVAAs), supply chain management (SCM), and system dynamics (SD) in the construction project management realm, an exhaustive mixed-mode quantitative survey was conducted among key participants in the South African infrastructure sector. Public sector clients, consulting engineers and contractors that were involved in civil engineering projects were surveyed repeatedly with approximately five survey instruments at convenient intervals. Results arising from the study, inter-alia, indicate that: an appreciable amount of NVAAs occur in South African construction; these NVAAs become further compounded when propagated into other value adding activities (VAAs) in the construction process; the identified NVAAs equally perpetrate the menace associated with poor performance to the detriment of the achievement of cost, H&S, quality, and time project targets, and the root cause of these NVAAs that often contribute to poor performance is not far from the much reported „shortage of skills‟ in South Africa. Notable contributions to the body of knowledge include SD models are extendable regardless of the source of their empirical data as evident in the qualitative models proposed in this study; within the SD domain, it is advisable to consider the „competence‟ of individuals assigned to tasks especially in a developing country as this study revealed that human resources issues predominate among the sources of NVAAs that eventuate in a range of poor project performance; the NVAAs that occur, and their causes on projects are perceived to be due to lapses and / or inadequacies that involved the entire construction supply chain; there is no single construction process / task that is immune from being affected by NVAAs; and within the South African, and by implication construction context generally iii in developing countries, the adequacy of required knowledge among project stakeholders is the most crucial determinant of project performance. As opposed to what is obtainable in developed countries, the construction industry in developing countries, particularly in South Africa, should take advantage of knowledge management (KM) techniques such as brainstorming, communities of practices, and face-to-face interactions. These techniques can be driven through appropriate mentorship programmes, industry focused built environment education, and other human resources driven avenues that do not necessarily require substantial investment in technologies, so that to a large extent organisations in the industry can prioritise KM, and thereafter, continually engage in it for future performance improvement. Using inferential statistical methods for hypotheses testing, and SD concepts for creating qualitative models led to a range of recommendations which, inter-alia, propose that halting the tide of NVAAs and poor performance requires the management of both tacit and explicit knowledge gained in construction; and most importantly, it requires the assurance that „competence‟ is the overriding criteria for selecting project partners, and also, for assigning either design or construction related activities to responsible parties involved in project realisation in South Africa. In effect, in order to engender a culture of continuous improvement in South African construction, other considerations should be subservient to „competence‟ in the construction supply chain. Competence must be located among everyone involved in project realisation, that is, enhancing the competence of all involved in project realisation is as good as ensuring performance improvement, which in turn, equates to the acceleration of project delivery in South Africa.
- Full Text:
- Date Issued: 2011
- Authors: Emuze, Fidelis Abumere
- Date: 2011
- Subjects: Construction industry -- South Africa -- Management , Project management -- South Africa , Construction projects -- Management , Business logistics -- South Africa -- Management
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9678 , http://hdl.handle.net/10948/1642 , Construction industry -- South Africa -- Management , Project management -- South Africa , Construction projects -- Management , Business logistics -- South Africa -- Management
- Description: In general, dreams are conceived, ideas are conceptualised, and initiatives are embarked upon in order to alter the state of realities. Dreams change realities; when mechanisms are put in place to realise them, dreams succeed. However, anecdotal evidence as well as empirical findings has continued to reiterate the difficulties associated with realising dreams related to construction projects. Extending the „dream‟ analogy to the South African construction industry context therefore paints an uninspiring picture. Dreams associated with construction do not have a 100% chance of becoming realities as evident in reported poor project performance in the industry. Shattered dreams in the form of poor performing projects, poorly implemented construction processes, or worst, projects delivered at the expense of unexpected cost to the client as a direct result of poor H&S or time overruns, negate the intent of dreams. This thesis is primarily concerned with project performance related bottlenecks in South African construction. After an extensive review of related literature that entails the analysis of publications related to non-value adding activities (NVAAs), supply chain management (SCM), and system dynamics (SD) in the construction project management realm, an exhaustive mixed-mode quantitative survey was conducted among key participants in the South African infrastructure sector. Public sector clients, consulting engineers and contractors that were involved in civil engineering projects were surveyed repeatedly with approximately five survey instruments at convenient intervals. Results arising from the study, inter-alia, indicate that: an appreciable amount of NVAAs occur in South African construction; these NVAAs become further compounded when propagated into other value adding activities (VAAs) in the construction process; the identified NVAAs equally perpetrate the menace associated with poor performance to the detriment of the achievement of cost, H&S, quality, and time project targets, and the root cause of these NVAAs that often contribute to poor performance is not far from the much reported „shortage of skills‟ in South Africa. Notable contributions to the body of knowledge include SD models are extendable regardless of the source of their empirical data as evident in the qualitative models proposed in this study; within the SD domain, it is advisable to consider the „competence‟ of individuals assigned to tasks especially in a developing country as this study revealed that human resources issues predominate among the sources of NVAAs that eventuate in a range of poor project performance; the NVAAs that occur, and their causes on projects are perceived to be due to lapses and / or inadequacies that involved the entire construction supply chain; there is no single construction process / task that is immune from being affected by NVAAs; and within the South African, and by implication construction context generally iii in developing countries, the adequacy of required knowledge among project stakeholders is the most crucial determinant of project performance. As opposed to what is obtainable in developed countries, the construction industry in developing countries, particularly in South Africa, should take advantage of knowledge management (KM) techniques such as brainstorming, communities of practices, and face-to-face interactions. These techniques can be driven through appropriate mentorship programmes, industry focused built environment education, and other human resources driven avenues that do not necessarily require substantial investment in technologies, so that to a large extent organisations in the industry can prioritise KM, and thereafter, continually engage in it for future performance improvement. Using inferential statistical methods for hypotheses testing, and SD concepts for creating qualitative models led to a range of recommendations which, inter-alia, propose that halting the tide of NVAAs and poor performance requires the management of both tacit and explicit knowledge gained in construction; and most importantly, it requires the assurance that „competence‟ is the overriding criteria for selecting project partners, and also, for assigning either design or construction related activities to responsible parties involved in project realisation in South Africa. In effect, in order to engender a culture of continuous improvement in South African construction, other considerations should be subservient to „competence‟ in the construction supply chain. Competence must be located among everyone involved in project realisation, that is, enhancing the competence of all involved in project realisation is as good as ensuring performance improvement, which in turn, equates to the acceleration of project delivery in South Africa.
- Full Text:
- Date Issued: 2011
Preconditioning measurement and control system for a combustion engine in a vehicle
- Authors: Homann, Gregor
- Date: 2011
- Subjects: Internal combustion engines , Mechanical engineering
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9649 , http://hdl.handle.net/10948/d1010998 , Internal combustion engines , Mechanical engineering
- Description: Modern vehicles have to ful ll new CO2 emission and additionally customer comfort requirements to stay competitive. A major impact to the fuel consumption of an internal combustion engine (ICE) has the starting period. An ICE equipped with a preconditioning system which heats up the ICE much faster than a common ICE. This procedure of preconditioning is called peak heating. The main benet of preconditioning of an ICE is less fuel consumption. Recently the only way to obtain a fast heating up of an ICE is the injection of a higher amount of fuel during the starting period. This heat up procedure can be changed if a heat reservoir is available to the ICE during the starting period. In this case the additional injection of fuel is redundant and therefore the consumption during the starting period can be reduced. The major advantages of this strategy are achieved in cold ambient conditions. During this project di erent preconditioning strategies and di erent points of interaction in the coolant circuit of an ICE have been investigated. The preconditioning concepts have been evaluated according to their heating up performance and their implementation into the engine compartment. The results obtained by this project highlight that a system layout which enables a preheating of the cylinder block by a heat reservoir located in a bypass-line to the heater core is the most e ective point of interaction. The best results have been achieved with a coolant ow of 10 l/min at a temperature of 90 C. Furthermore, this project points out that the implementation of a preconditioning system into the oil cooler will achieve similar results. This strategy of preconditioning the engine oil reduces the internal frictions of the ICE which leads to a decreasing consumption. This solution is much more energy e cient and technically easier to implement into a modern vehicle with its limited space. An additional side e ect of the preconditioning of the oil is a longer service life of the ICE.
- Full Text:
- Date Issued: 2011
- Authors: Homann, Gregor
- Date: 2011
- Subjects: Internal combustion engines , Mechanical engineering
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9649 , http://hdl.handle.net/10948/d1010998 , Internal combustion engines , Mechanical engineering
- Description: Modern vehicles have to ful ll new CO2 emission and additionally customer comfort requirements to stay competitive. A major impact to the fuel consumption of an internal combustion engine (ICE) has the starting period. An ICE equipped with a preconditioning system which heats up the ICE much faster than a common ICE. This procedure of preconditioning is called peak heating. The main benet of preconditioning of an ICE is less fuel consumption. Recently the only way to obtain a fast heating up of an ICE is the injection of a higher amount of fuel during the starting period. This heat up procedure can be changed if a heat reservoir is available to the ICE during the starting period. In this case the additional injection of fuel is redundant and therefore the consumption during the starting period can be reduced. The major advantages of this strategy are achieved in cold ambient conditions. During this project di erent preconditioning strategies and di erent points of interaction in the coolant circuit of an ICE have been investigated. The preconditioning concepts have been evaluated according to their heating up performance and their implementation into the engine compartment. The results obtained by this project highlight that a system layout which enables a preheating of the cylinder block by a heat reservoir located in a bypass-line to the heater core is the most e ective point of interaction. The best results have been achieved with a coolant ow of 10 l/min at a temperature of 90 C. Furthermore, this project points out that the implementation of a preconditioning system into the oil cooler will achieve similar results. This strategy of preconditioning the engine oil reduces the internal frictions of the ICE which leads to a decreasing consumption. This solution is much more energy e cient and technically easier to implement into a modern vehicle with its limited space. An additional side e ect of the preconditioning of the oil is a longer service life of the ICE.
- Full Text:
- Date Issued: 2011
Slow delivery of low-income housing at munipal level with special reference to the Nelson Mandela Bay Munipality
- Authors: Scheepers, Mario Jacques
- Date: 2011
- Subjects: SLow-income housing -- South Africa -- Port Elizabeth , Municipal services -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9671 , http://hdl.handle.net/10948/d1015968
- Description: The provision of adequate housing is an important part of government's commitment towards providing a better quality of life to the people of South Africa. Housing delivery is, however, not taking place to the extent and speed that will eliminate the backlog in housing delivery. The researcher aims to (i) evaluate and investigate the reasons why housing delivery at municipal level is slow, (ii) discuss the effect of inefficient implementation on delivery, (iii) examine the influence of the lack of infrastructure and the lack of skilled municipal officials and employees of construction organisations and the processes followed to make a success of housing delivery. Chapter 2, Section 26(1), Act 108 0f 1996 of the Constitution of South Africa states that everyone has the right to have access to adequate housing. This places an obligation on government to provide adequate housing to all citizens, within the restriction of available resources. The lack of land hampers the speed at which municipalities can deliver low-income housing. Housing and basic infrastructure (water, sewer and roads) form an integral part of the governments commitment to reduce poverty and improve the quality of life of South Africans. The fact that municipalities do not have capacity to address housing delivery and the fact that most artisans are near retirement age also influence the rate that houses can be delivered. Adequate housing processes are needed for housing delivery to take place, without it government will not succeed in delivering adequate housing. The results of the survey and the literature review confirm that housing delivery at municipality level is slow, that municipal officials need training and more employees to insure that housing delivery improves. The results also show the importance of infrastructure and land, the importance of implementing housing policies and processes adequately.
- Full Text:
- Date Issued: 2011
- Authors: Scheepers, Mario Jacques
- Date: 2011
- Subjects: SLow-income housing -- South Africa -- Port Elizabeth , Municipal services -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:9671 , http://hdl.handle.net/10948/d1015968
- Description: The provision of adequate housing is an important part of government's commitment towards providing a better quality of life to the people of South Africa. Housing delivery is, however, not taking place to the extent and speed that will eliminate the backlog in housing delivery. The researcher aims to (i) evaluate and investigate the reasons why housing delivery at municipal level is slow, (ii) discuss the effect of inefficient implementation on delivery, (iii) examine the influence of the lack of infrastructure and the lack of skilled municipal officials and employees of construction organisations and the processes followed to make a success of housing delivery. Chapter 2, Section 26(1), Act 108 0f 1996 of the Constitution of South Africa states that everyone has the right to have access to adequate housing. This places an obligation on government to provide adequate housing to all citizens, within the restriction of available resources. The lack of land hampers the speed at which municipalities can deliver low-income housing. Housing and basic infrastructure (water, sewer and roads) form an integral part of the governments commitment to reduce poverty and improve the quality of life of South Africans. The fact that municipalities do not have capacity to address housing delivery and the fact that most artisans are near retirement age also influence the rate that houses can be delivered. Adequate housing processes are needed for housing delivery to take place, without it government will not succeed in delivering adequate housing. The results of the survey and the literature review confirm that housing delivery at municipality level is slow, that municipal officials need training and more employees to insure that housing delivery improves. The results also show the importance of infrastructure and land, the importance of implementing housing policies and processes adequately.
- Full Text:
- Date Issued: 2011
Tailoring a lean product development framework for the South African automotive industry
- Authors: Mund, Klaudia
- Date: 2011
- Subjects: Lean manufacturing , Automobile industry and trade -- South Africa , Production management -- South Africa , Globalization
- Language: English
- Type: Thesis , Doctoral , DTech (Operations Management)
- Identifier: vital:9605 , http://hdl.handle.net/10948/1660 , Lean manufacturing , Automobile industry and trade -- South Africa , Production management -- South Africa , Globalization
- Description: Globalization in the automotive industry exerts enormous pressure on automotive manufacturers and forces many global companies to expand into emerging markets, which results in adopting new ways to manage product design and development. Excellence in product design and development offers an opportunity to gain competitive advantage and can be achieved by implementing Toyota´s Lean Product Development System (LPDS). Although in the last three years Toyota has been severely challenged by the global economic crisis, by a series of recalls resulting in reputation damage and also by natural disasters such as the recent tsunamis - the world can still learn from Toyota´s successes embodied in the lean concept and practices, which are integral to Toyota´s ‘way of life’. The LPDS model (Morgan & Liker 2006) has captured the attention of academics worldwide (including this researcher) thanks to the following key characteristics: shorter development times, less engineering hours involved in development, lower manufacturing costs, higher customer satisfaction and fewer defects reported. In the academic world, lean product development (LPD) is a new field of exploration and thus relevant literature and numbers of studies available are limited. However, scientists are asking questions about successful adaptation and adoption of this model to other environments beyond Toyota. Similarly, the researcher aimed in this thesis to find answers to its main research question, namely: ‘What would be a suitable LPD model for the South African automotive industry?’ South Africa (SA) is a country with a strong manufacturing tradition and although the automotive sector is the third-largest segment in the South African economy and its vehicle market is the largest on the African continent in a global perspective SA´s contribution is relatively small as it produces only 0.61% of the global motor vehicle volume (OICA 2011). While the country strives to secure sustainable development for the automotive industry and seeks to improve its global competitiveness, companies operating in SA are currently faced with several unique challenges and problems. Lean has been expanding slowly in SA and some companies in the local automotive industry have implemented the lean concept into production areas to improve their operational excellence and performance. However, it is a search for excellence in product development (PD) that could best contribute to improved sustainability for the iv automotive industry and also provide an important strategic spur towards global competitiveness. The primary intention of this research was to develop an integrated LPD framework tailored for SA´s automotive industry. Considering this, it was necessary to determine current PD capabilities at domestic and international companies operating in SA´s automotive industry so as to examine levels of adaptation of LPD practices. A questionnaire survey and personal interviews involving all seven locally operating Original Equipment Manufacturers (OEMs), including Toyota, as well as 36 local automotive suppliers provided an empirical base for this investigation. This study indicates that SA plays an important supportive role in the global PD context. In spite of a strong manufacturing focus and very limited PD capabilities, SA´s automotive companies have already achieved a high level of ‘leanness’ in product engineering processes. However, on the downside, it appears that industry leaders and senior managers are sceptical about current and future capabilities and opportunities for SA in the designing and developing of global products.
- Full Text:
- Date Issued: 2011
- Authors: Mund, Klaudia
- Date: 2011
- Subjects: Lean manufacturing , Automobile industry and trade -- South Africa , Production management -- South Africa , Globalization
- Language: English
- Type: Thesis , Doctoral , DTech (Operations Management)
- Identifier: vital:9605 , http://hdl.handle.net/10948/1660 , Lean manufacturing , Automobile industry and trade -- South Africa , Production management -- South Africa , Globalization
- Description: Globalization in the automotive industry exerts enormous pressure on automotive manufacturers and forces many global companies to expand into emerging markets, which results in adopting new ways to manage product design and development. Excellence in product design and development offers an opportunity to gain competitive advantage and can be achieved by implementing Toyota´s Lean Product Development System (LPDS). Although in the last three years Toyota has been severely challenged by the global economic crisis, by a series of recalls resulting in reputation damage and also by natural disasters such as the recent tsunamis - the world can still learn from Toyota´s successes embodied in the lean concept and practices, which are integral to Toyota´s ‘way of life’. The LPDS model (Morgan & Liker 2006) has captured the attention of academics worldwide (including this researcher) thanks to the following key characteristics: shorter development times, less engineering hours involved in development, lower manufacturing costs, higher customer satisfaction and fewer defects reported. In the academic world, lean product development (LPD) is a new field of exploration and thus relevant literature and numbers of studies available are limited. However, scientists are asking questions about successful adaptation and adoption of this model to other environments beyond Toyota. Similarly, the researcher aimed in this thesis to find answers to its main research question, namely: ‘What would be a suitable LPD model for the South African automotive industry?’ South Africa (SA) is a country with a strong manufacturing tradition and although the automotive sector is the third-largest segment in the South African economy and its vehicle market is the largest on the African continent in a global perspective SA´s contribution is relatively small as it produces only 0.61% of the global motor vehicle volume (OICA 2011). While the country strives to secure sustainable development for the automotive industry and seeks to improve its global competitiveness, companies operating in SA are currently faced with several unique challenges and problems. Lean has been expanding slowly in SA and some companies in the local automotive industry have implemented the lean concept into production areas to improve their operational excellence and performance. However, it is a search for excellence in product development (PD) that could best contribute to improved sustainability for the iv automotive industry and also provide an important strategic spur towards global competitiveness. The primary intention of this research was to develop an integrated LPD framework tailored for SA´s automotive industry. Considering this, it was necessary to determine current PD capabilities at domestic and international companies operating in SA´s automotive industry so as to examine levels of adaptation of LPD practices. A questionnaire survey and personal interviews involving all seven locally operating Original Equipment Manufacturers (OEMs), including Toyota, as well as 36 local automotive suppliers provided an empirical base for this investigation. This study indicates that SA plays an important supportive role in the global PD context. In spite of a strong manufacturing focus and very limited PD capabilities, SA´s automotive companies have already achieved a high level of ‘leanness’ in product engineering processes. However, on the downside, it appears that industry leaders and senior managers are sceptical about current and future capabilities and opportunities for SA in the designing and developing of global products.
- Full Text:
- Date Issued: 2011
The simulation of vehicle engine cooling in a climatic chamber
- Authors: Badenhorst, Kenneth Merwin
- Date: 2011
- Subjects: Automobiles -- Motors -- Cooling systems , Automobiles -- Air conditioning
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9615 , http://hdl.handle.net/10948/1454 , Automobiles -- Motors -- Cooling systems , Automobiles -- Air conditioning
- Description: The simulation of vehicle engine cooling validation in a Climatic chamber will benefit all vehicle manufacturers that are responsible for the design or the localization of parts used in a vehicle's engine cooling system. The ability to test the vehicle in-house allows testing at any time of the year; it provides repeatable and comparative data, and accelerates component level approval, which in itself reduces program timing and cost. For this dissertation road level testing was conducted in Upington using a TD1200 Superflow towing dynamometer, while the in-house testing was performed on a ROTOTEST chassis dynamometer in a Climatic chamber. All tests were conducted according to GENERAL MOTORS SOUTH AFRICA global testing standards. Statistical analyses of the test data were used to determine the relationship between parameters measured and results obtained. The major contributors to the simulation process was identified and implemented to improve measurement quality and test results. The result was an accurate simulation between road and chamber testing, hence the possibility of moving away from road testing and conduct simulated chamber testing. The presented dissertation is useful for the understanding of basic vehicle cooling testing and the methodology of simulated testing in an environmentally controlled chamber.
- Full Text:
- Date Issued: 2011
- Authors: Badenhorst, Kenneth Merwin
- Date: 2011
- Subjects: Automobiles -- Motors -- Cooling systems , Automobiles -- Air conditioning
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9615 , http://hdl.handle.net/10948/1454 , Automobiles -- Motors -- Cooling systems , Automobiles -- Air conditioning
- Description: The simulation of vehicle engine cooling validation in a Climatic chamber will benefit all vehicle manufacturers that are responsible for the design or the localization of parts used in a vehicle's engine cooling system. The ability to test the vehicle in-house allows testing at any time of the year; it provides repeatable and comparative data, and accelerates component level approval, which in itself reduces program timing and cost. For this dissertation road level testing was conducted in Upington using a TD1200 Superflow towing dynamometer, while the in-house testing was performed on a ROTOTEST chassis dynamometer in a Climatic chamber. All tests were conducted according to GENERAL MOTORS SOUTH AFRICA global testing standards. Statistical analyses of the test data were used to determine the relationship between parameters measured and results obtained. The major contributors to the simulation process was identified and implemented to improve measurement quality and test results. The result was an accurate simulation between road and chamber testing, hence the possibility of moving away from road testing and conduct simulated chamber testing. The presented dissertation is useful for the understanding of basic vehicle cooling testing and the methodology of simulated testing in an environmentally controlled chamber.
- Full Text:
- Date Issued: 2011
The value added by facilities management services to an organisation's core business
- Authors: Relu, Lona
- Date: 2011
- Subjects: Facility management , Production management , Operations management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9724 , http://hdl.handle.net/10948/d1012047 , Facility management , Production management , Operations management
- Description: The main objective of the study was to define FM in its broader context and identify ways of exposing its value to the organisation’s core business. The study firstly included defining FM, its scope and nature to provide an in-depth overview and understanding of the discipline. Secondly, the study discussed in detail the level of support of FM by top or senior management. Thirdly, the study discussed the importance of quality management in enhancing the value of FM within an organisation. Lastly, the study discussed how service level agreements can be utilised to enhance the value of FM within the organisation. Questionnaires were distributed via electronic mail and some hand-delivered to private, public organisations and government parastatals to gather their views on how they think FM can add value to their organisations. Questionnaires were sent out to various professionals from various organisations that employ FM services based on the aforementioned objectives. The findings from the survey showed that most organisations understand and have the knowledge about FM but there is no set and defined scope; the scope of FM differs in various organisations; soft services are grouped together and branded as FM services; FM is moderately incorporated throughout and top management still sees FM as adding no value to the organisation’s core business. The results also show that FM needs to adopt strategies such as understanding and working towards the organisation’s goals and objectives; ensuring sustainability in FM services; providing superior quality service and projecting defined and improved levels of service linking service to the organisation’s culture and facilitating organisational change for it to gain support from top management. The majority of respondents incorporating FM in their organisations agree with the benefits afforded by this discipline and have developed and implemented quality management systems that are linked to their business strategies and, by doing so, have enhanced their organisation’s performance levels. Service Level agreements are not being utilised by the majority of the organisations the few organisations that utilise SLA’s, have benefited a great deal from SLAs.
- Full Text:
- Date Issued: 2011
- Authors: Relu, Lona
- Date: 2011
- Subjects: Facility management , Production management , Operations management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9724 , http://hdl.handle.net/10948/d1012047 , Facility management , Production management , Operations management
- Description: The main objective of the study was to define FM in its broader context and identify ways of exposing its value to the organisation’s core business. The study firstly included defining FM, its scope and nature to provide an in-depth overview and understanding of the discipline. Secondly, the study discussed in detail the level of support of FM by top or senior management. Thirdly, the study discussed the importance of quality management in enhancing the value of FM within an organisation. Lastly, the study discussed how service level agreements can be utilised to enhance the value of FM within the organisation. Questionnaires were distributed via electronic mail and some hand-delivered to private, public organisations and government parastatals to gather their views on how they think FM can add value to their organisations. Questionnaires were sent out to various professionals from various organisations that employ FM services based on the aforementioned objectives. The findings from the survey showed that most organisations understand and have the knowledge about FM but there is no set and defined scope; the scope of FM differs in various organisations; soft services are grouped together and branded as FM services; FM is moderately incorporated throughout and top management still sees FM as adding no value to the organisation’s core business. The results also show that FM needs to adopt strategies such as understanding and working towards the organisation’s goals and objectives; ensuring sustainability in FM services; providing superior quality service and projecting defined and improved levels of service linking service to the organisation’s culture and facilitating organisational change for it to gain support from top management. The majority of respondents incorporating FM in their organisations agree with the benefits afforded by this discipline and have developed and implemented quality management systems that are linked to their business strategies and, by doing so, have enhanced their organisation’s performance levels. Service Level agreements are not being utilised by the majority of the organisations the few organisations that utilise SLA’s, have benefited a great deal from SLAs.
- Full Text:
- Date Issued: 2011
User-interface evaluation metrics for a typical M-Learning application
- Authors: Kantore, Adelin
- Date: 2011
- Subjects: User interfaces (Computer systems) , Mobile communication systems
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9749 , http://hdl.handle.net/10948/1452 , User interfaces (Computer systems) , Mobile communication systems
- Description: Usability is seen as an important aspect for the quality of an M-learning application. Yet very little research has been conducted in this area – particularly in South Africa. Even though the trials of M-learning projects have been witnessed in the country during the last five years, very little is known about the systems that were implemented as regards their usability. Additionally, metrics and measures used in evaluating usability have not been reported. A need exists for relevant metrics to M-learning usability. The primary objective of this work was to propose metrics and measures – for the purpose of evaluating the User-Interfacedesign usability of M-learning application. The research included a literature review of M-learning, as well as the development of metrics and measures based on the Goal Question Metric (GQM) Model. This model has helped provide a reference model and measurements for evaluating the User-InterfaceUsability. A case study was used as a research strategy. An application called Kontax was selected for evaluation by users and expert reviewers. Data-collection methods consisted of User Testing and Heuristics evaluations. Data-gathering instruments included the use of surveys and user- satisfaction questionnaires based on the proposed metrics, task scenarios and expert-reviewed questionnaires based on the proposed metrics; all these instruments were developed. It was found that, although the users thought the system was very interesting, and they wished to hear more about it in the future, the system nevertheless had usability flaws which made it difficult to use. All the users failed to register so that they could use the system; additionally, the system-error messages did not help the users recognize, and recover from an error – leaving the user to simply log out. Help was not adequate, thus making it difficult for first-time users to know what to do when they needed support. The system was also said to have a lot of information presented on its home page, which caused the user to be disoriented. The Kontax application has usability flaws which should be III attended to, in order to improve its usability. The proposed metrics proved to be very useful in evaluating the usability of the tool.
- Full Text:
- Date Issued: 2011
- Authors: Kantore, Adelin
- Date: 2011
- Subjects: User interfaces (Computer systems) , Mobile communication systems
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9749 , http://hdl.handle.net/10948/1452 , User interfaces (Computer systems) , Mobile communication systems
- Description: Usability is seen as an important aspect for the quality of an M-learning application. Yet very little research has been conducted in this area – particularly in South Africa. Even though the trials of M-learning projects have been witnessed in the country during the last five years, very little is known about the systems that were implemented as regards their usability. Additionally, metrics and measures used in evaluating usability have not been reported. A need exists for relevant metrics to M-learning usability. The primary objective of this work was to propose metrics and measures – for the purpose of evaluating the User-Interfacedesign usability of M-learning application. The research included a literature review of M-learning, as well as the development of metrics and measures based on the Goal Question Metric (GQM) Model. This model has helped provide a reference model and measurements for evaluating the User-InterfaceUsability. A case study was used as a research strategy. An application called Kontax was selected for evaluation by users and expert reviewers. Data-collection methods consisted of User Testing and Heuristics evaluations. Data-gathering instruments included the use of surveys and user- satisfaction questionnaires based on the proposed metrics, task scenarios and expert-reviewed questionnaires based on the proposed metrics; all these instruments were developed. It was found that, although the users thought the system was very interesting, and they wished to hear more about it in the future, the system nevertheless had usability flaws which made it difficult to use. All the users failed to register so that they could use the system; additionally, the system-error messages did not help the users recognize, and recover from an error – leaving the user to simply log out. Help was not adequate, thus making it difficult for first-time users to know what to do when they needed support. The system was also said to have a lot of information presented on its home page, which caused the user to be disoriented. The Kontax application has usability flaws which should be III attended to, in order to improve its usability. The proposed metrics proved to be very useful in evaluating the usability of the tool.
- Full Text:
- Date Issued: 2011
Vision-guided tracking of complex tree-dimensional seams for robotic gas metal arc welding
- Authors: Hamed, Maien
- Date: 2011
- Subjects: Robot vision , Robotics , Gas metal arc welding
- Language: English
- Type: Thesis , Masters , MEngineering (Mechatronics)
- Identifier: vital:9646 , http://hdl.handle.net/10948/1428 , Robot vision , Robotics , Gas metal arc welding
- Description: Automation of welding systems is often restricted by the requirements of spatial information of the seams to be welded. When this cannot be obtained from the design of the welded parts and maintained using accurate xturing, the use of a seam teaching or tracking system becomes necessary. Optical seam teaching and tracking systems have many advantages compared to systems implemented with other sensor families. Direct vision promises to be a viable strategy for implementing optical seam tracking, which has been mainly done with laser vision. The current work investigated direct vision as a strategy for optical seam teaching and tracking. A robotic vision system has been implemented, consisting of an articulated robot, a hand mounted camera and a control computer. A description of the calibration methods and the seam and feature detection and three-dimensional scene reconstruction is given. The results showed that direct vision is a suitable strategy for seam detection and learning. A discussion of generalizing the method used as an architecture for simultanious system calibration and measurement estimation is provided.
- Full Text:
- Date Issued: 2011
- Authors: Hamed, Maien
- Date: 2011
- Subjects: Robot vision , Robotics , Gas metal arc welding
- Language: English
- Type: Thesis , Masters , MEngineering (Mechatronics)
- Identifier: vital:9646 , http://hdl.handle.net/10948/1428 , Robot vision , Robotics , Gas metal arc welding
- Description: Automation of welding systems is often restricted by the requirements of spatial information of the seams to be welded. When this cannot be obtained from the design of the welded parts and maintained using accurate xturing, the use of a seam teaching or tracking system becomes necessary. Optical seam teaching and tracking systems have many advantages compared to systems implemented with other sensor families. Direct vision promises to be a viable strategy for implementing optical seam tracking, which has been mainly done with laser vision. The current work investigated direct vision as a strategy for optical seam teaching and tracking. A robotic vision system has been implemented, consisting of an articulated robot, a hand mounted camera and a control computer. A description of the calibration methods and the seam and feature detection and three-dimensional scene reconstruction is given. The results showed that direct vision is a suitable strategy for seam detection and learning. A discussion of generalizing the method used as an architecture for simultanious system calibration and measurement estimation is provided.
- Full Text:
- Date Issued: 2011
Wireless rotational process monitoring system
- Authors: Odendaal, Morné
- Date: 2011
- Subjects: Manufacturing processes -- Automation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9599 , http://hdl.handle.net/10948/1347 , Manufacturing processes -- Automation
- Description: The manufacturing industry is constantly looking for ways to reduce production costs and at the same time to increase productivity. Automation of common manufacturing operations is one of these methods. By automating common manufacturing operations; various machines, robots, control systems and information technologies are used to reduce the overall human input requirement (mental and physical). Recent advances in technology have made it possible to now also automate (or facilitate) the maintenance requirement of these machines and tools. Modern tools and machines, which can estimate when it will fail or when failure is imminent have obvious advantages for predictive maintenance purposes. Another function of this technology is to determine how efficiently a tool or machine operates, or what the quality of the produced goods is. Predictive maintenance can decrease manufacturing plant or machine down times – which have a positive effect on cost-savings – has gained considerable importance over the last two decades.
- Full Text:
- Date Issued: 2011
- Authors: Odendaal, Morné
- Date: 2011
- Subjects: Manufacturing processes -- Automation
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: vital:9599 , http://hdl.handle.net/10948/1347 , Manufacturing processes -- Automation
- Description: The manufacturing industry is constantly looking for ways to reduce production costs and at the same time to increase productivity. Automation of common manufacturing operations is one of these methods. By automating common manufacturing operations; various machines, robots, control systems and information technologies are used to reduce the overall human input requirement (mental and physical). Recent advances in technology have made it possible to now also automate (or facilitate) the maintenance requirement of these machines and tools. Modern tools and machines, which can estimate when it will fail or when failure is imminent have obvious advantages for predictive maintenance purposes. Another function of this technology is to determine how efficiently a tool or machine operates, or what the quality of the produced goods is. Predictive maintenance can decrease manufacturing plant or machine down times – which have a positive effect on cost-savings – has gained considerable importance over the last two decades.
- Full Text:
- Date Issued: 2011
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
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
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
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
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
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
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
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
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
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
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