Wireless ICT monitoring for hydroponic agriculture
- Authors: Ndame, Loic Andre Stephane
- Date: 2015
- Subjects: Mobile apps -- South Africa , Hydroponics -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/3605 , vital:20445
- Description: It is becoming increasingly evident that agriculture is playing a pivotal role in the socio-economic development of South Africa. The agricultural sector is important because it contributes approximately 2% to the gross domestic product of the country. However, many factors impact on the sustainability of traditional agriculture in South Africa. Unpredictable climatic conditions, land degradation and a lack of information and awareness of innovative farming solutions are among the factors plaguing the South African agricultural landscape. Various farming techniques have been looked at in order to mitigate these challenges. Among these interventions are the introduction of organic agriculture, greenhouse agriculture and hydroponic agriculture, which is the focus area of this study. Hydroponic agriculture is a method of precision agriculture where plants are grown in a mineral nutrient solution instead labour- intensive activity that requires an incessant monitoring of the farm environment in order to ensure a successful harvest. Hydroponic agriculture, however, presents a number of challenges that can be mitigated by leveraging the recent mobile Information and Communication Technologies (ICTs) breakthroughs. This dissertation reports on the development of a wireless ICT monitoring application for hydroponic agriculture: HydroWatcher mobile app. HydroWatcher is a complex system that is composed of several interlacing parts and this study will be focusing on the development of the mobile app, the front-end of the system. This focus is motivated by the fact that in such systems the front-end, being the part that the users interact with, is critical for the acceptance of the system. However, in order to design and develop any part of HydroWatcher, it is crucial to understand the context of hydroponic agriculture in South Africa. Therefore, complementary objectives of this study are to identify the critical factors that impact hydroponic agriculture as well as the challenges faced by hydroponic farmers in South Africa. Thus, it leads to the elicitation of the requirements for the design and development of HydroWatcher. This study followed a mixed methods approach, including interviews, observations, exploration of hydroponic farming, to collect the data, which will best enable the researcher to understand the activities relating to hydroponic agriculture. A qualitative content analysis was followed to analyse the data and to constitute the requirements for the system and later to assert their applicability to the mobile app. HydroWatcher proposes to couple recent advances in mobile technology development, like the Android platform, with the contemporary advances in electronics necessary for the creation of wireless sensor nodes, as well as Human Computer interaction guidelines tailored for developing countries, in order to boost the user experience.
- Full Text:
- Date Issued: 2015
- Authors: Ndame, Loic Andre Stephane
- Date: 2015
- Subjects: Mobile apps -- South Africa , Hydroponics -- South Africa
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/3605 , vital:20445
- Description: It is becoming increasingly evident that agriculture is playing a pivotal role in the socio-economic development of South Africa. The agricultural sector is important because it contributes approximately 2% to the gross domestic product of the country. However, many factors impact on the sustainability of traditional agriculture in South Africa. Unpredictable climatic conditions, land degradation and a lack of information and awareness of innovative farming solutions are among the factors plaguing the South African agricultural landscape. Various farming techniques have been looked at in order to mitigate these challenges. Among these interventions are the introduction of organic agriculture, greenhouse agriculture and hydroponic agriculture, which is the focus area of this study. Hydroponic agriculture is a method of precision agriculture where plants are grown in a mineral nutrient solution instead labour- intensive activity that requires an incessant monitoring of the farm environment in order to ensure a successful harvest. Hydroponic agriculture, however, presents a number of challenges that can be mitigated by leveraging the recent mobile Information and Communication Technologies (ICTs) breakthroughs. This dissertation reports on the development of a wireless ICT monitoring application for hydroponic agriculture: HydroWatcher mobile app. HydroWatcher is a complex system that is composed of several interlacing parts and this study will be focusing on the development of the mobile app, the front-end of the system. This focus is motivated by the fact that in such systems the front-end, being the part that the users interact with, is critical for the acceptance of the system. However, in order to design and develop any part of HydroWatcher, it is crucial to understand the context of hydroponic agriculture in South Africa. Therefore, complementary objectives of this study are to identify the critical factors that impact hydroponic agriculture as well as the challenges faced by hydroponic farmers in South Africa. Thus, it leads to the elicitation of the requirements for the design and development of HydroWatcher. This study followed a mixed methods approach, including interviews, observations, exploration of hydroponic farming, to collect the data, which will best enable the researcher to understand the activities relating to hydroponic agriculture. A qualitative content analysis was followed to analyse the data and to constitute the requirements for the system and later to assert their applicability to the mobile app. HydroWatcher proposes to couple recent advances in mobile technology development, like the Android platform, with the contemporary advances in electronics necessary for the creation of wireless sensor nodes, as well as Human Computer interaction guidelines tailored for developing countries, in order to boost the user experience.
- Full Text:
- Date Issued: 2015
Guidelines for the analysis of student web usage in support of primary educational objectives
- Authors: Von Schoultz, Dean John
- Date: 2015
- Subjects: Information behavior , Searching behavior , Internet in higher education , World Wide Web , Educational technology
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/4965 , vital:20772
- Description: The Internet and World Wide Web provides huge amounts of information to individuals with access to it. Information is an important driving factor of education and higher education has experienced massive adoption rates of information and communication technologies, and accessing the Web is not an uncommon practice within a higher educational institution. The Web provides numerous benefits and many students rely on the Web for information, communication and technical support. However, the immense amount of information available on the Web has brought about some negative side effects associated with abundant information. Whether the Web is a positive influence on students’ academic well-being within higher education is a difficult question to answer. To understand how the Web is used by students within a higher education institution is not an easy task. However, there are ways to understand the Web usage behaviour of students. Using established methods for gathering useful information from data produced by an institution, Web usage behaviours of students within a higher education institution could be analysed and presented. This dissertation presents guidance for analysing Web traffic within a higher educational institution in order to gain insight into the Web usage behaviours of students. This insight can provide educators with valuable information to bolster their decision-making capacity towards achieving their educational goals.
- Full Text:
- Date Issued: 2015
- Authors: Von Schoultz, Dean John
- Date: 2015
- Subjects: Information behavior , Searching behavior , Internet in higher education , World Wide Web , Educational technology
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/4965 , vital:20772
- Description: The Internet and World Wide Web provides huge amounts of information to individuals with access to it. Information is an important driving factor of education and higher education has experienced massive adoption rates of information and communication technologies, and accessing the Web is not an uncommon practice within a higher educational institution. The Web provides numerous benefits and many students rely on the Web for information, communication and technical support. However, the immense amount of information available on the Web has brought about some negative side effects associated with abundant information. Whether the Web is a positive influence on students’ academic well-being within higher education is a difficult question to answer. To understand how the Web is used by students within a higher education institution is not an easy task. However, there are ways to understand the Web usage behaviour of students. Using established methods for gathering useful information from data produced by an institution, Web usage behaviours of students within a higher education institution could be analysed and presented. This dissertation presents guidance for analysing Web traffic within a higher educational institution in order to gain insight into the Web usage behaviours of students. This insight can provide educators with valuable information to bolster their decision-making capacity towards achieving their educational goals.
- Full Text:
- Date Issued: 2015
Using vehicle activated signs as an integrated measure to improve road safety in South Africa
- Authors: Swanepoel, Charl
- Date: 2015
- Subjects: Traffic signs and signals -- South Africa , Electronic traffic controls
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/3745 , vital:20460
- Description: Road safety is an aspect of major concern on road networks, not only on a local scale in South Africa, but also on a global scale. South Africa is experiencing an unacceptably high rate of fatal road traffic crashes and as a result has one of the highest per capita rate of road fatalities in the world. The Global Plan for the Decade of Action for Road Safety 2011 – 2020 was published in 2011 by the World Health Organisation (WHO) to guide and assist countries with the improvement of road safety. The management of vehicle speeds is one of numerous important interventions identified in the Global Plan. The technical and economic feasibility of using a specific Road safety is an aspect of major concern on road networks, not only on a local scale in South Africa, but also on a global scale. South Africa is experiencing an unacceptably high rate of fatal road traffic crashes and as a result has one of the highest per capita rate of road fatalities in the world. The Global Plan for the Decade of Action for Road Safety 2011 – 2020 was published in 2011 by the World Health Organisation (WHO) to guide and assist countries with the improvement of road safety. The management of vehicle speeds is one of numerous important interventions identified in the Global Plan. The technical and economic feasibility of using a specific technology, namely Vehicle Activated Signs (VAS), to contribute to the overall improvement of road safety on a national level in South Africa were investigated, with particular emphasis on the improvement of road safety through the reduction of fatal road traffic crashes. VAS are part of a range of measures that can be used to curb vehicle speeds, similar to conventional measures like speed cameras and traffic calming devices. VAS technology has seen limited use in South extrapolation of results from SCC’s VAS effectiveness study, and the application of these results to the South African road safety and road user statistics for the one year period March 2011 to March 2012. Key factors relating to speed and general driver obedience were also taken into consideration. It was established that the use of VAS would lead to a moderate reduction in the number of fatal road traffic crashes that occur annually, which in turn holds financial and socio-economic benefits for South Africa. A comparison of selected products available from two South African based electronic road sign manufacturing companies with conventional VAS was also carried out, focussing on product function, use and cost. It has been concluded that it would be technically and economically feasible to introduce VAS on the South African road network to improve the prevailing road safety situation.
- Full Text:
- Date Issued: 2015
- Authors: Swanepoel, Charl
- Date: 2015
- Subjects: Traffic signs and signals -- South Africa , Electronic traffic controls
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/3745 , vital:20460
- Description: Road safety is an aspect of major concern on road networks, not only on a local scale in South Africa, but also on a global scale. South Africa is experiencing an unacceptably high rate of fatal road traffic crashes and as a result has one of the highest per capita rate of road fatalities in the world. The Global Plan for the Decade of Action for Road Safety 2011 – 2020 was published in 2011 by the World Health Organisation (WHO) to guide and assist countries with the improvement of road safety. The management of vehicle speeds is one of numerous important interventions identified in the Global Plan. The technical and economic feasibility of using a specific Road safety is an aspect of major concern on road networks, not only on a local scale in South Africa, but also on a global scale. South Africa is experiencing an unacceptably high rate of fatal road traffic crashes and as a result has one of the highest per capita rate of road fatalities in the world. The Global Plan for the Decade of Action for Road Safety 2011 – 2020 was published in 2011 by the World Health Organisation (WHO) to guide and assist countries with the improvement of road safety. The management of vehicle speeds is one of numerous important interventions identified in the Global Plan. The technical and economic feasibility of using a specific technology, namely Vehicle Activated Signs (VAS), to contribute to the overall improvement of road safety on a national level in South Africa were investigated, with particular emphasis on the improvement of road safety through the reduction of fatal road traffic crashes. VAS are part of a range of measures that can be used to curb vehicle speeds, similar to conventional measures like speed cameras and traffic calming devices. VAS technology has seen limited use in South extrapolation of results from SCC’s VAS effectiveness study, and the application of these results to the South African road safety and road user statistics for the one year period March 2011 to March 2012. Key factors relating to speed and general driver obedience were also taken into consideration. It was established that the use of VAS would lead to a moderate reduction in the number of fatal road traffic crashes that occur annually, which in turn holds financial and socio-economic benefits for South Africa. A comparison of selected products available from two South African based electronic road sign manufacturing companies with conventional VAS was also carried out, focussing on product function, use and cost. It has been concluded that it would be technically and economically feasible to introduce VAS on the South African road network to improve the prevailing road safety situation.
- Full Text:
- Date Issued: 2015
Research and development of an intelligent AGV-based material handling system for industrial applications
- Authors: Ferreira, Tremaine Pierre
- Date: 2015
- Subjects: Robotics -- Industrial applications Artificial intelligence , Mechatronics -- South Africa
- Language: English
- Type: Thesis , Masters , MEng
- Identifier: http://hdl.handle.net/10948/21711 , vital:29738
- Description: The use of autonomous robots in industrial applications is growing in popularity and possesses the following advantages: cost effectiveness, job efficiency and safety aspects. Despite the advantages, the major drawback to using autonomous robots is the cost involved to acquire such robots. It is the aim of GMSA to develop a low cost AGV capable of performing material handling in an industrial environment. Collective autonomous robots are often used to perform tasks, that is, more than one working together to achieve a common goal. The intelligent controller, responsible for establishing coordination between the individual robots, plays a key role in managing the tasks of each robot to achieve the common goal. This dissertation addresses the development of an AGV capable of such functionality. Key research areas include: the development of an autonomous coupling system, integration of key safety devices and the development of an intelligent control strategy that can be used to govern the operation of multiple AGVs in an area.
- Full Text:
- Date Issued: 2015
- Authors: Ferreira, Tremaine Pierre
- Date: 2015
- Subjects: Robotics -- Industrial applications Artificial intelligence , Mechatronics -- South Africa
- Language: English
- Type: Thesis , Masters , MEng
- Identifier: http://hdl.handle.net/10948/21711 , vital:29738
- Description: The use of autonomous robots in industrial applications is growing in popularity and possesses the following advantages: cost effectiveness, job efficiency and safety aspects. Despite the advantages, the major drawback to using autonomous robots is the cost involved to acquire such robots. It is the aim of GMSA to develop a low cost AGV capable of performing material handling in an industrial environment. Collective autonomous robots are often used to perform tasks, that is, more than one working together to achieve a common goal. The intelligent controller, responsible for establishing coordination between the individual robots, plays a key role in managing the tasks of each robot to achieve the common goal. This dissertation addresses the development of an AGV capable of such functionality. Key research areas include: the development of an autonomous coupling system, integration of key safety devices and the development of an intelligent control strategy that can be used to govern the operation of multiple AGVs in an area.
- Full Text:
- Date Issued: 2015
The development of a framework to reduce water and energy consumption through the use of water and energy value stream mapping for the South African manufacturing industry
- Authors: Davies, Edward
- Date: 2015
- Subjects: Lean manufacturing -- South Africa , Stream mapping -- South Africa , Water consumption -- South Africa
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: http://hdl.handle.net/10948/4160 , vital:20564
- Description: The Republic of South Africa’s energy economy is under immense pressure and the main energy utility, Eskom, cannot reliably generate sufficient electrical energy to meet its customer demand. Water security in South Africa is also under threat as the country is currently amidst a water crisis. The South African manufacturing industry is the sector consuming the largest portion of the total energy consumption and second largest portion of the total water consumption (excluding urban use) nationally. Water and energy efficiency improvement is becoming imperative for organisational success as well as national economic sustainability. This is due to the significant increase in the cost of both electrical energy and water in recent years, and the drop in the reserve energy margin below the minimum level required for sustainable operation of energy utilities. The research objective therefore was to develop a Lean-based water and energy efficiency improvement framework for the manufacturing industry to encourage and realise a reduced demand for energy and water in it. A literature review was conducted on the water and energy landscape in South Africa, Lean manufacturing principles and their positive natural influence on water and energy efficiency, and the Value Stream Mapping tool. The survey of water and energy wastes in the manufacturing industry yielded the creation of standardised water and energy waste categories for use in conjunction with the conventional Lean wastes, tools and techniques. The literature survey indicated that the implementation of Lean manufacturing techniques naturally leads to the improvement of energy and water intensity. The researcher hypothesised that there is even greater potential for water and energy savings if a Lean-based tool is developed to specifically focus on the improvement of energy and water efficiency. A framework for this tool was developed through the literature survey. The tool is based on the Value Stream Mapping tool. A practical experiment was then conducted to establish the effectiveness of the tool in the South African manufacturing industry. The experiment design included an outline of the forecasting and statistical validation techniques to ensure the integrity of data utilised for approving or disproving the set hypotheses. The results of the practical experiment yielded positive results, confirming the hypothesis that the implementation of the developed framework will lead to improved energy and water efficiency in the manufacturing industry. After an explanation of the experimental results, the study concluded with recommendations and conclusions based on the findings.
- Full Text:
- Date Issued: 2015
- Authors: Davies, Edward
- Date: 2015
- Subjects: Lean manufacturing -- South Africa , Stream mapping -- South Africa , Water consumption -- South Africa
- Language: English
- Type: Thesis , Doctoral , DTech
- Identifier: http://hdl.handle.net/10948/4160 , vital:20564
- Description: The Republic of South Africa’s energy economy is under immense pressure and the main energy utility, Eskom, cannot reliably generate sufficient electrical energy to meet its customer demand. Water security in South Africa is also under threat as the country is currently amidst a water crisis. The South African manufacturing industry is the sector consuming the largest portion of the total energy consumption and second largest portion of the total water consumption (excluding urban use) nationally. Water and energy efficiency improvement is becoming imperative for organisational success as well as national economic sustainability. This is due to the significant increase in the cost of both electrical energy and water in recent years, and the drop in the reserve energy margin below the minimum level required for sustainable operation of energy utilities. The research objective therefore was to develop a Lean-based water and energy efficiency improvement framework for the manufacturing industry to encourage and realise a reduced demand for energy and water in it. A literature review was conducted on the water and energy landscape in South Africa, Lean manufacturing principles and their positive natural influence on water and energy efficiency, and the Value Stream Mapping tool. The survey of water and energy wastes in the manufacturing industry yielded the creation of standardised water and energy waste categories for use in conjunction with the conventional Lean wastes, tools and techniques. The literature survey indicated that the implementation of Lean manufacturing techniques naturally leads to the improvement of energy and water intensity. The researcher hypothesised that there is even greater potential for water and energy savings if a Lean-based tool is developed to specifically focus on the improvement of energy and water efficiency. A framework for this tool was developed through the literature survey. The tool is based on the Value Stream Mapping tool. A practical experiment was then conducted to establish the effectiveness of the tool in the South African manufacturing industry. The experiment design included an outline of the forecasting and statistical validation techniques to ensure the integrity of data utilised for approving or disproving the set hypotheses. The results of the practical experiment yielded positive results, confirming the hypothesis that the implementation of the developed framework will lead to improved energy and water efficiency in the manufacturing industry. After an explanation of the experimental results, the study concluded with recommendations and conclusions based on the findings.
- Full Text:
- Date Issued: 2015
The impact of non-compliance with Eskom procurement policies
- Authors: Mvelase, Thokozile Olivia
- Date: 2015
- Subjects: Eskom (Firm) , Industrial procurement -- Management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/9140 , vital:26468
- Description: Supply Chain Management (SCM) has an overwhelming impact on firms as it directly impacts on sales and costs. Therefore, it must be a core competency for any organization and thus SCM expertise is highly valued in organisations. Procurement of goods and services has a major impact on the successful execution of the project. Procurement can help the business, ensuring that all the goods and services they buy will be of the right quality, quantity and price, and they will be delivered ‘just in time’. The application of procurement policies and practices, using fair and open procedures, is crucial not only for attracting efficient contractors and suppliers, but also to safeguard the principle of accountability and the cost-effective use of funds. Before awarding a tender, there is a substantial amount of work to be undertaken by the project manager, contracts manager, end user, buyer, and authorising committees. Commitment from personnel involved in contract awarding is not adequate. Furthermore, the Eskom governance process sometimes contributes to delays in awarding a contract. before the enquiry and tender documentation is sent out to the suppliers on the tender list, the core team involved in the procurement process verifies that the enquiry is complete and correct. Should there be contractual or legal issues during the execution of the project in the form of say a contract that has been issued with unsuitable clauses, solving the problem becomes difficult. Contractors will sometimes use contract clauses to suit themselves, and take advantage of the employer, causing cost overruns due to the difficulties in managing the contract. Eskom’s commercial activities are governed by the Public Finance Management Act (PFMA) and Constitution of South Africa, which states that an organisation such as Eskom should have in place “an appropriate procurement and provisioning system which is fair, equitable, transparent, competitive, and cost-effective.” This can eliminate irregularities in contracts, since they can have a serious economic impact, interfere with fair competition, and destroy confidence in the integrity and functioning of public administration Such irregularities may lead to costs overruns on projects where incompetent contractors are awarded a contract. Incorrect financial forecasting is a very serious issue, and needs to be addressed in order to help strengthen the cash flow and forecasting within Eskom. This research strategy is intended for quantifying observations of human behaviour, with the emphasis on exact measurements. The primary data for this study was generated through the administration of a structured questionnaire survey conducted among engineers, project managers, contract managers, and forensics personnel. The secondary data for the present study was gathered from literature in the form of open ended questionnaire from the same personnel. Poor commitment of buyers and chain approval meetings being shifted affect the delays in awarding of contracts. Lack of training of contract managers, absence of legal representative’s advice and squad checking meetings not being represented properly contributes to contracts being awarded with unsuitable clauses. Managers specifically forcing contracts to be awarded to a specific contractor, nepotism or favoritism, politics and contractor greediness, relate to irregularities in contracts. Lack of experience, revision of scope (unclarified scope), project delays, less effort being made when forecasting and unforeseen circumstances, such as strikes, and forces of nature, relate to incorrect financial forecasting. Continuous training and commitment of all personnel involved in the project environment is important, therefore Eskom personnel in the project environment should work as a team in an integrated way. Adequate time should be spent, and thorough checks made, to ensure that documents sent out for tendering conform to requirements. Involvement of all the supporting functions must be maximised. Code of ethics training and application is very crucial in the project environment, and the current governance policies should be adhered to by all stakeholders in the project.
- Full Text:
- Date Issued: 2015
- Authors: Mvelase, Thokozile Olivia
- Date: 2015
- Subjects: Eskom (Firm) , Industrial procurement -- Management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/9140 , vital:26468
- Description: Supply Chain Management (SCM) has an overwhelming impact on firms as it directly impacts on sales and costs. Therefore, it must be a core competency for any organization and thus SCM expertise is highly valued in organisations. Procurement of goods and services has a major impact on the successful execution of the project. Procurement can help the business, ensuring that all the goods and services they buy will be of the right quality, quantity and price, and they will be delivered ‘just in time’. The application of procurement policies and practices, using fair and open procedures, is crucial not only for attracting efficient contractors and suppliers, but also to safeguard the principle of accountability and the cost-effective use of funds. Before awarding a tender, there is a substantial amount of work to be undertaken by the project manager, contracts manager, end user, buyer, and authorising committees. Commitment from personnel involved in contract awarding is not adequate. Furthermore, the Eskom governance process sometimes contributes to delays in awarding a contract. before the enquiry and tender documentation is sent out to the suppliers on the tender list, the core team involved in the procurement process verifies that the enquiry is complete and correct. Should there be contractual or legal issues during the execution of the project in the form of say a contract that has been issued with unsuitable clauses, solving the problem becomes difficult. Contractors will sometimes use contract clauses to suit themselves, and take advantage of the employer, causing cost overruns due to the difficulties in managing the contract. Eskom’s commercial activities are governed by the Public Finance Management Act (PFMA) and Constitution of South Africa, which states that an organisation such as Eskom should have in place “an appropriate procurement and provisioning system which is fair, equitable, transparent, competitive, and cost-effective.” This can eliminate irregularities in contracts, since they can have a serious economic impact, interfere with fair competition, and destroy confidence in the integrity and functioning of public administration Such irregularities may lead to costs overruns on projects where incompetent contractors are awarded a contract. Incorrect financial forecasting is a very serious issue, and needs to be addressed in order to help strengthen the cash flow and forecasting within Eskom. This research strategy is intended for quantifying observations of human behaviour, with the emphasis on exact measurements. The primary data for this study was generated through the administration of a structured questionnaire survey conducted among engineers, project managers, contract managers, and forensics personnel. The secondary data for the present study was gathered from literature in the form of open ended questionnaire from the same personnel. Poor commitment of buyers and chain approval meetings being shifted affect the delays in awarding of contracts. Lack of training of contract managers, absence of legal representative’s advice and squad checking meetings not being represented properly contributes to contracts being awarded with unsuitable clauses. Managers specifically forcing contracts to be awarded to a specific contractor, nepotism or favoritism, politics and contractor greediness, relate to irregularities in contracts. Lack of experience, revision of scope (unclarified scope), project delays, less effort being made when forecasting and unforeseen circumstances, such as strikes, and forces of nature, relate to incorrect financial forecasting. Continuous training and commitment of all personnel involved in the project environment is important, therefore Eskom personnel in the project environment should work as a team in an integrated way. Adequate time should be spent, and thorough checks made, to ensure that documents sent out for tendering conform to requirements. Involvement of all the supporting functions must be maximised. Code of ethics training and application is very crucial in the project environment, and the current governance policies should be adhered to by all stakeholders in the project.
- Full Text:
- Date Issued: 2015
Organizational culture in the South African construction industry : effects on work-life balance and individual performance
- Dlamini, Gcebekile Tikhokhile
- Authors: Dlamini, Gcebekile Tikhokhile
- Date: 2015
- Subjects: Construction industry -- South Africa , Work-life balance -- South Africa , Corporate culture -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9702 , http://hdl.handle.net/10948/d1018513
- Description: The South African construction industry plays an important role in the economy and overall development of the country, with respect to its total fiscal contribution and the total number of people who are employed. In addition, it is a major contributor to infrastructure development. However, the human resource base within this industry is confronted with a plethora of challenges that are inherent to the construction industry. These manifest themselves in stressful working conditions and long working hours, labour intensive jobs, reduced job security due to job losses and short-term projects, and the feeble health and safety (H&S) standards. Together with a variety of socio-economic and political issues, these challenges form a perceived and broad organisational culture of this industry, which impacts on the industry‟s productivity. As construction management efforts in the development of the human resources base increase, the industry recognises that work-life balance is an important and critical issue in the 21st century. Construction management is a discipline that embodies two interdependent dimensions; the management of the business of construction and the management of projects. Of the latter, the key principles thereof are, as part of a management strategy, planning, organizing, leading, controlling and coordinating projects. To achieve these strategic components, an effective human resource base is required. Work-life balance is therefore a management issue and organizational culture sets a backdrop from which it can be understood. This study focused on the status of the organisational culture of the production establishments that form part of the construction industry and the manner in which it manifests on the work-life balance of the workers. Furthermore, the correlation between work-life balance and individual work performance was examined. An exploratory research approach was adopted and the research technique followed an interview protocol. The main findings demonstrate that the South African construction industry is predominantly a clan culture with minor characteristics of the hierarchy, adhocracy and market cultures. Furthermore, work-life balance is difficult to attain and it influences individual work performance. The main conclusion is that organizational culture in construction firms is imbalanced. Thus, the main recommendation is that the industry adopts a balanced organizational culture and modern human resource practices.
- Full Text:
- Date Issued: 2015
- Authors: Dlamini, Gcebekile Tikhokhile
- Date: 2015
- Subjects: Construction industry -- South Africa , Work-life balance -- South Africa , Corporate culture -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9702 , http://hdl.handle.net/10948/d1018513
- Description: The South African construction industry plays an important role in the economy and overall development of the country, with respect to its total fiscal contribution and the total number of people who are employed. In addition, it is a major contributor to infrastructure development. However, the human resource base within this industry is confronted with a plethora of challenges that are inherent to the construction industry. These manifest themselves in stressful working conditions and long working hours, labour intensive jobs, reduced job security due to job losses and short-term projects, and the feeble health and safety (H&S) standards. Together with a variety of socio-economic and political issues, these challenges form a perceived and broad organisational culture of this industry, which impacts on the industry‟s productivity. As construction management efforts in the development of the human resources base increase, the industry recognises that work-life balance is an important and critical issue in the 21st century. Construction management is a discipline that embodies two interdependent dimensions; the management of the business of construction and the management of projects. Of the latter, the key principles thereof are, as part of a management strategy, planning, organizing, leading, controlling and coordinating projects. To achieve these strategic components, an effective human resource base is required. Work-life balance is therefore a management issue and organizational culture sets a backdrop from which it can be understood. This study focused on the status of the organisational culture of the production establishments that form part of the construction industry and the manner in which it manifests on the work-life balance of the workers. Furthermore, the correlation between work-life balance and individual work performance was examined. An exploratory research approach was adopted and the research technique followed an interview protocol. The main findings demonstrate that the South African construction industry is predominantly a clan culture with minor characteristics of the hierarchy, adhocracy and market cultures. Furthermore, work-life balance is difficult to attain and it influences individual work performance. The main conclusion is that organizational culture in construction firms is imbalanced. Thus, the main recommendation is that the industry adopts a balanced organizational culture and modern human resource practices.
- Full Text:
- Date Issued: 2015
Wireless industrial intelligent controller for a non-linear system
- Authors: Fernandes, John Manuel
- Date: 2015
- Subjects: Neural networks (Computer science) , Linear systems
- Language: English
- Type: Thesis , Masters , MEngineering (Mechatronics)
- Identifier: http://hdl.handle.net/10948/9021 , vital:26457
- Description: Modern neural network (NN) based control schemes have surmounted many of the limitations found in the traditional control approaches. Nevertheless, these modern control techniques have only recently been introduced for use on high-specification Programmable Logic Controllers (PLCs) and usually at a very high cost in terms of the required software and hardware. This ‗intelligent‘ control in the sector of industrial automation, specifically on standard PLCs thus remains an area of study that is open to further research and development. The research documented in this thesis examined the effectiveness of linear traditional control schemes such as Proportional Integral Derivative (PID), Lead and Lead-Lag control, in comparison to non-linear NN based control schemes when applied on a strongly non-linear platform. To this end, a mechatronic-type balancing system, namely, the Ball-on-Wheel (BOW) system was designed, constructed and modelled. Thereafter various traditional and intelligent controllers were implemented in order to control the system. The BOW platform may be taken to represent any single-input, single-output (SISO) non-linear system in use in the real world. The system makes use of current industrial technology including a standard PLC as the digital computational platform, a servo drive and wireless access for remote control. The results gathered from the research revealed that NN based control schemes (i.e. Pure NN and NN-PID), although comparatively slower in response, have greater advantages over traditional controllers in that they are able to adapt to external system changes as well as system non-linearity through a process of learning. These controllers also reduce the guess work that is usually involved with the traditional control approaches where cumbersome modelling, linearization or manual tuning is required. Furthermore, the research showed that online-learning adaptive traditional controllers such as the NN-PID controller which maintains the best of both the intelligent and traditional controllers may be implemented easily and with minimum expense on standard PLCs.
- Full Text:
- Date Issued: 2015
- Authors: Fernandes, John Manuel
- Date: 2015
- Subjects: Neural networks (Computer science) , Linear systems
- Language: English
- Type: Thesis , Masters , MEngineering (Mechatronics)
- Identifier: http://hdl.handle.net/10948/9021 , vital:26457
- Description: Modern neural network (NN) based control schemes have surmounted many of the limitations found in the traditional control approaches. Nevertheless, these modern control techniques have only recently been introduced for use on high-specification Programmable Logic Controllers (PLCs) and usually at a very high cost in terms of the required software and hardware. This ‗intelligent‘ control in the sector of industrial automation, specifically on standard PLCs thus remains an area of study that is open to further research and development. The research documented in this thesis examined the effectiveness of linear traditional control schemes such as Proportional Integral Derivative (PID), Lead and Lead-Lag control, in comparison to non-linear NN based control schemes when applied on a strongly non-linear platform. To this end, a mechatronic-type balancing system, namely, the Ball-on-Wheel (BOW) system was designed, constructed and modelled. Thereafter various traditional and intelligent controllers were implemented in order to control the system. The BOW platform may be taken to represent any single-input, single-output (SISO) non-linear system in use in the real world. The system makes use of current industrial technology including a standard PLC as the digital computational platform, a servo drive and wireless access for remote control. The results gathered from the research revealed that NN based control schemes (i.e. Pure NN and NN-PID), although comparatively slower in response, have greater advantages over traditional controllers in that they are able to adapt to external system changes as well as system non-linearity through a process of learning. These controllers also reduce the guess work that is usually involved with the traditional control approaches where cumbersome modelling, linearization or manual tuning is required. Furthermore, the research showed that online-learning adaptive traditional controllers such as the NN-PID controller which maintains the best of both the intelligent and traditional controllers may be implemented easily and with minimum expense on standard PLCs.
- Full Text:
- Date Issued: 2015
Ultra-high precision machining of contact lens polymers
- Authors: Olufayo, Oluwole Ayodeji
- Date: 2015
- Subjects: Contact lenses , Polymers
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/3001 , vital:20385
- Description: Contact lens manufacture requires a high level of accuracy and surface integrity in the range of a few nanometres. Amidst numerous optical manufacturing techniques, single-point diamond turning is widely employed in the making of contact lenses due to its capability of producing optical surfaces of complex shapes and nanometric accuracy. For process optimisation, it is ideal to assess the effects of various conditions and also establish their relationships with the surface finish. Presently, there is little information available on the performance of single point diamond turning when machining contact lens polymers. Therefore, the research work undertaken herewith is aimed at testing known facts in contact lens diamond turning and investigating the performance of ultra-high precision manufacturing of contact lens polymers. Experimental tests were conducted on Roflufocon E, which is a commercially available contact lens polymer and on Precitech Nanoform Ultra-grind 250 precision machining. Tests were performed at varying cutting feeds, speed and depth of cut. Initial experimental tests investigated the influence of process factors affecting surface finish in the UHPM of lenses. The acquired data were statistically analysed using Response Surface Method (RSM) to create a model of the process. Subsequently, a model which uses Runge-Kutta’s fourth order non-linear finite series scheme was developed and adapted to deduce the force occurring at the tool tip. These forces were also statistically analysed and modelled to also predict the effects process factors have on cutting force. Further experimental tests were aimed at establishing the presence of the triboelectric wear phenomena occurring during polymer machining and identifying the most influential process factors. Results indicate that feed rate is a significant factor in the generation of high optical surface quality. In addition, the depth of cut was identified as a significant factor in the generation of low surface roughness in lenses. The influence some of these process factors had was notably linked to triboelectric effects. This tribological effect was generated from the continuous rubbing action of magnetised chips on the cutting tool. This further stresses the presence of high static charging during cutting. Moderately humid cutting conditions presented an adequate means for static charge control and displayed improved surface finishes. In all experimental tests, the feed rate was identified as the most significant factor within the range of cutting parameters employed. Hence, the results validated the fact that feed rate had a high influence in polymer machining. The work also established the relationship on how surface roughness of an optical lens responded to monitoring signals and parameters such as force, feed, speed and depth of cut during machining and it generated models for prediction of surface finishes and appropriate selection of parameters. Furthermore, the study provides a molecular simulation analysis for validating observed conditions occurring at the nanometric scale in polymer machining. This is novel in molecular polymer modelling. The outcome of this research has contributed significantly to the body of knowledge and has provided basic information in the area of precision manufacturing of optical components of high surface integrity such as contact lenses. The application of the research findings presented here cuts across various fields such as medicine, semi-conductors, aerospace, defence, telecom, lasers, instrumentation and life sciences.
- Full Text:
- Date Issued: 2015
- Authors: Olufayo, Oluwole Ayodeji
- Date: 2015
- Subjects: Contact lenses , Polymers
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: http://hdl.handle.net/10948/3001 , vital:20385
- Description: Contact lens manufacture requires a high level of accuracy and surface integrity in the range of a few nanometres. Amidst numerous optical manufacturing techniques, single-point diamond turning is widely employed in the making of contact lenses due to its capability of producing optical surfaces of complex shapes and nanometric accuracy. For process optimisation, it is ideal to assess the effects of various conditions and also establish their relationships with the surface finish. Presently, there is little information available on the performance of single point diamond turning when machining contact lens polymers. Therefore, the research work undertaken herewith is aimed at testing known facts in contact lens diamond turning and investigating the performance of ultra-high precision manufacturing of contact lens polymers. Experimental tests were conducted on Roflufocon E, which is a commercially available contact lens polymer and on Precitech Nanoform Ultra-grind 250 precision machining. Tests were performed at varying cutting feeds, speed and depth of cut. Initial experimental tests investigated the influence of process factors affecting surface finish in the UHPM of lenses. The acquired data were statistically analysed using Response Surface Method (RSM) to create a model of the process. Subsequently, a model which uses Runge-Kutta’s fourth order non-linear finite series scheme was developed and adapted to deduce the force occurring at the tool tip. These forces were also statistically analysed and modelled to also predict the effects process factors have on cutting force. Further experimental tests were aimed at establishing the presence of the triboelectric wear phenomena occurring during polymer machining and identifying the most influential process factors. Results indicate that feed rate is a significant factor in the generation of high optical surface quality. In addition, the depth of cut was identified as a significant factor in the generation of low surface roughness in lenses. The influence some of these process factors had was notably linked to triboelectric effects. This tribological effect was generated from the continuous rubbing action of magnetised chips on the cutting tool. This further stresses the presence of high static charging during cutting. Moderately humid cutting conditions presented an adequate means for static charge control and displayed improved surface finishes. In all experimental tests, the feed rate was identified as the most significant factor within the range of cutting parameters employed. Hence, the results validated the fact that feed rate had a high influence in polymer machining. The work also established the relationship on how surface roughness of an optical lens responded to monitoring signals and parameters such as force, feed, speed and depth of cut during machining and it generated models for prediction of surface finishes and appropriate selection of parameters. Furthermore, the study provides a molecular simulation analysis for validating observed conditions occurring at the nanometric scale in polymer machining. This is novel in molecular polymer modelling. The outcome of this research has contributed significantly to the body of knowledge and has provided basic information in the area of precision manufacturing of optical components of high surface integrity such as contact lenses. The application of the research findings presented here cuts across various fields such as medicine, semi-conductors, aerospace, defence, telecom, lasers, instrumentation and life sciences.
- Full Text:
- Date Issued: 2015
Design of a low-cost autonomous guided cart for material handling
- Authors: Cawood, Gareth James
- Date: 2015
- Subjects: Automobiles -- Design and construction , Automobiles -- Automatic control , Vehicles -- Automatic control
- Language: English
- Type: Thesis , Masters , MEngineering
- Identifier: vital:9655
- Description: This dissertation covers the design and manufacture of an autonomous guided cart (AGC) for use in the material handling industry. General Motors South Africa (GMSA) requires a low-cost AGC for use in their Struandale plant. A budget of R35 000 per unit was proposed. The researcher, in collaboration with staff at GM, compiled a list of engineering requirements for the AGC. After research into the unique problems of the project, an examination of a previous design attempt by staff of GM Thailand, the researcher developed a new design, the subject of this report. Different solutions for each design problem were investigated before the design was finalised. A three-wheeled vehicle was designed making use of two motors in a differential-drive setup to control motion. Navigation is via a line-following mechanism, using an induction sensor-array in conjunction with a pre-laid metallic strip. To aid the design, the system was modelled to understand the different control elements at play. The researcher developed software for several aspects of the design: for the PLC controlling the system and motors; for a microcontroller that communicates with the PLC and a wireless module; for a computer server that communicates with a second wireless device, receiving information from the PLC; and a web interface to view this information. These form the SCADA integration of the project. The final product meets the GMSA specifications. It is a robot capable of towing a trolley of mass not exceeding 350 kg. While the robot is able to navigate a pre-laid route, it cannot reliably stop at marked locations. It is possible to monitor the system via a web-interface. The robot is capable of operating for an entire 8-hour shift before the batteries need to be recharged. The total cost of the prototype was R26 340.
- Full Text:
- Date Issued: 2015
- Authors: Cawood, Gareth James
- Date: 2015
- Subjects: Automobiles -- Design and construction , Automobiles -- Automatic control , Vehicles -- Automatic control
- Language: English
- Type: Thesis , Masters , MEngineering
- Identifier: vital:9655
- Description: This dissertation covers the design and manufacture of an autonomous guided cart (AGC) for use in the material handling industry. General Motors South Africa (GMSA) requires a low-cost AGC for use in their Struandale plant. A budget of R35 000 per unit was proposed. The researcher, in collaboration with staff at GM, compiled a list of engineering requirements for the AGC. After research into the unique problems of the project, an examination of a previous design attempt by staff of GM Thailand, the researcher developed a new design, the subject of this report. Different solutions for each design problem were investigated before the design was finalised. A three-wheeled vehicle was designed making use of two motors in a differential-drive setup to control motion. Navigation is via a line-following mechanism, using an induction sensor-array in conjunction with a pre-laid metallic strip. To aid the design, the system was modelled to understand the different control elements at play. The researcher developed software for several aspects of the design: for the PLC controlling the system and motors; for a microcontroller that communicates with the PLC and a wireless module; for a computer server that communicates with a second wireless device, receiving information from the PLC; and a web interface to view this information. These form the SCADA integration of the project. The final product meets the GMSA specifications. It is a robot capable of towing a trolley of mass not exceeding 350 kg. While the robot is able to navigate a pre-laid route, it cannot reliably stop at marked locations. It is possible to monitor the system via a web-interface. The robot is capable of operating for an entire 8-hour shift before the batteries need to be recharged. The total cost of the prototype was R26 340.
- Full Text:
- Date Issued: 2015
A comparative study of performance and efficiency of a tube and fin type domestic solar water heat collector
- Authors: Kleyn, Gysbert
- Date: 2015
- Subjects: Solar collectors , Solar water heaters -- Testing , Solar heating
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/7959 , vital:24329
- Description: The main purpose of this research project was to do a comparative study, by identifying a testing methodology for transient conditions, through which to allow the expression of the relative thermal performance of two DSWH collectors in comparison. The study started off by considering literature about Solar Domestic Water Heaters and National Standards-based test methods, most of which were for Steady State testing conditions. Thereafter establishing a testing methodology and setup, identifying factors to be considered. The results were analyzed and conclusions drawn. The hypothesis was to allow the reduction in the complexity of testing equipment and methods, and by doing transient condition testing and still utilizing the Hottel-Whillier-Bliss relationship as a way of expressing efficiency, the hypothesis was proven.
- Full Text:
- Date Issued: 2015
- Authors: Kleyn, Gysbert
- Date: 2015
- Subjects: Solar collectors , Solar water heaters -- Testing , Solar heating
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/7959 , vital:24329
- Description: The main purpose of this research project was to do a comparative study, by identifying a testing methodology for transient conditions, through which to allow the expression of the relative thermal performance of two DSWH collectors in comparison. The study started off by considering literature about Solar Domestic Water Heaters and National Standards-based test methods, most of which were for Steady State testing conditions. Thereafter establishing a testing methodology and setup, identifying factors to be considered. The results were analyzed and conclusions drawn. The hypothesis was to allow the reduction in the complexity of testing equipment and methods, and by doing transient condition testing and still utilizing the Hottel-Whillier-Bliss relationship as a way of expressing efficiency, the hypothesis was proven.
- Full Text:
- Date Issued: 2015
Maintenance management systems of on-campus student hostels at Nigerian universities
- Authors: Adamu, Anita Dzikwi
- Date: 2015
- Subjects: School buildings -- Maintenance and repair , Dormitories -- Nigeria , Nigeria -- Student housing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9710 , http://hdl.handle.net/10948/d1020168
- Description: Most universities have long recognised the importance and contribution of on-campus hostels to the learning process. In so doing, most of these institutions have provided and maintained building facilities for academic purposes (teaching and research). Hostels are integral components of most campuses of Nigerian universities, and they are part of the built assets of the institutions in terms of both administration and maintenance management. Currently, there is little understanding of the maintenance management systems of on-campus hostel buildings in both the public and the private universities. Moreover, there is a dearth of research evidence demonstrating that there is an appreciable difference in the maintenance management systems of the Federal, State and private universities in Nigeria. This research aimed at establishing an understanding of maintenance management systems of on-campus hostel buildings at Nigerian universities owned by the Federal and State governments and the Private Sector, relative to stipulated criteria for best practice.The qualitative method of research inquiry that is rooted in the phenomenological paradigm was employed in the investigations. The research activities included a comprehensive review of the related literature and study of selected cases. The North-central geopolitical zone of Nigeria was the selected geographical scope of this research. Ten universities were purposefully selected for the study, and they include three Federal, four state and three private universities. The nature and differences in the research questions necessitated generating different forms of data. The questions that were related to the maintenance management systems for the hostels in place at the universities were addressed with the outcomes of interviews with the hostel managers. The questions that were about the structures and current conditions of the hostel buildings at the three categories of universities were addressed with data that were generated from condition assessments of the facilities and physical observations with the aid of cameras. The study reveals apparent deteriorated and unhealthy conditions of most of the on-campus hostels at the public universities, while those of the private universities are satisfactory. The research also found that the maintenance management systems in use at all the universities are reactive and lack proper planning and coordination of maintenance activities. There is no significant difference in the maintenance management systems of hostels at the public and the private universities and the systems have major negative impact on the conditions of the buildings and their performances. The research has developed a conceptual model for the study of maintenance management informed by the theoretical framework. The model considered the impact of the external environmental factors on the management and maintenance of the hostels. Secondly, the interrelationships of strategic and performance management with maintenance management in developing an effective maintenance management system were established. The study has achieved its aim of establishing an understanding of maintenance management systems of on-campus hostel buildings at Nigerian universities owned by the Federal and, State governments and the Private Sector. The maintenance management model developed in the study is recommended to maintenance management departments as a guide for effective maintenance of the built facilities in their institutions.
- Full Text:
- Date Issued: 2015
- Authors: Adamu, Anita Dzikwi
- Date: 2015
- Subjects: School buildings -- Maintenance and repair , Dormitories -- Nigeria , Nigeria -- Student housing
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:9710 , http://hdl.handle.net/10948/d1020168
- Description: Most universities have long recognised the importance and contribution of on-campus hostels to the learning process. In so doing, most of these institutions have provided and maintained building facilities for academic purposes (teaching and research). Hostels are integral components of most campuses of Nigerian universities, and they are part of the built assets of the institutions in terms of both administration and maintenance management. Currently, there is little understanding of the maintenance management systems of on-campus hostel buildings in both the public and the private universities. Moreover, there is a dearth of research evidence demonstrating that there is an appreciable difference in the maintenance management systems of the Federal, State and private universities in Nigeria. This research aimed at establishing an understanding of maintenance management systems of on-campus hostel buildings at Nigerian universities owned by the Federal and State governments and the Private Sector, relative to stipulated criteria for best practice.The qualitative method of research inquiry that is rooted in the phenomenological paradigm was employed in the investigations. The research activities included a comprehensive review of the related literature and study of selected cases. The North-central geopolitical zone of Nigeria was the selected geographical scope of this research. Ten universities were purposefully selected for the study, and they include three Federal, four state and three private universities. The nature and differences in the research questions necessitated generating different forms of data. The questions that were related to the maintenance management systems for the hostels in place at the universities were addressed with the outcomes of interviews with the hostel managers. The questions that were about the structures and current conditions of the hostel buildings at the three categories of universities were addressed with data that were generated from condition assessments of the facilities and physical observations with the aid of cameras. The study reveals apparent deteriorated and unhealthy conditions of most of the on-campus hostels at the public universities, while those of the private universities are satisfactory. The research also found that the maintenance management systems in use at all the universities are reactive and lack proper planning and coordination of maintenance activities. There is no significant difference in the maintenance management systems of hostels at the public and the private universities and the systems have major negative impact on the conditions of the buildings and their performances. The research has developed a conceptual model for the study of maintenance management informed by the theoretical framework. The model considered the impact of the external environmental factors on the management and maintenance of the hostels. Secondly, the interrelationships of strategic and performance management with maintenance management in developing an effective maintenance management system were established. The study has achieved its aim of establishing an understanding of maintenance management systems of on-campus hostel buildings at Nigerian universities owned by the Federal and, State governments and the Private Sector. The maintenance management model developed in the study is recommended to maintenance management departments as a guide for effective maintenance of the built facilities in their institutions.
- Full Text:
- Date Issued: 2015
Single event upset testing of flash based field programmable gate arrays
- Authors: Potgieter, Juan-Pierre
- Date: 2015
- Subjects: Field programmable gate arrays
- Language: English
- Type: Thesis , Masters , MEngineering
- Identifier: http://hdl.handle.net/10948/12520 , vital:27083
- Description: In the last 50 years microelectronics have advanced at an exponential rate, causing microelectronic devices to shrink, have very low operating voltages and increased complexities; all this has made circuits more sensitive to various kinds of failures. These trends allowed soft errors, which up until recently was just a concern for space application, to become a major source of system failures of electronic products. The aim of this research paper was to investigate different mitigation techniques that prevent these soft errors in a Video Graphics Array (VGA) controller which is commonly used in projecting images captured by cameras. This controller was implemented on a Flash Based Field Programmable Gate array (FPGA). A test set-up was designed and implemented at NRF iThemba LABS, which was used to conduct the experiments necessary to evaluate the effectiveness of different mitigation techniques. The set-up was capable of handling multiple Device Under Tests (DUT) and had the ability to change the angle of incidence of each DUT. The DUTs were radiated with a 66MeV proton beam while the monitoring equipment observed any errors that had occurred. The results obtained indicated that all the implemented mitigation techniques tested on the VGA system improved the system’s capability of mitigating Single Event Upsets (SEU). The most effective mitigation technique was the OR-AND Multiplexer Single Event Transient (SET) filter technique. It was thus shown that mitigation techniques are viable options to prevent SEU in a VGA controller. The permanent SEU testing set-up which was designed and manufactured and was used to conduct the experiments, proved to be a practical option for further microelectronics testing at iThemba LABS.
- Full Text:
- Date Issued: 2015
- Authors: Potgieter, Juan-Pierre
- Date: 2015
- Subjects: Field programmable gate arrays
- Language: English
- Type: Thesis , Masters , MEngineering
- Identifier: http://hdl.handle.net/10948/12520 , vital:27083
- Description: In the last 50 years microelectronics have advanced at an exponential rate, causing microelectronic devices to shrink, have very low operating voltages and increased complexities; all this has made circuits more sensitive to various kinds of failures. These trends allowed soft errors, which up until recently was just a concern for space application, to become a major source of system failures of electronic products. The aim of this research paper was to investigate different mitigation techniques that prevent these soft errors in a Video Graphics Array (VGA) controller which is commonly used in projecting images captured by cameras. This controller was implemented on a Flash Based Field Programmable Gate array (FPGA). A test set-up was designed and implemented at NRF iThemba LABS, which was used to conduct the experiments necessary to evaluate the effectiveness of different mitigation techniques. The set-up was capable of handling multiple Device Under Tests (DUT) and had the ability to change the angle of incidence of each DUT. The DUTs were radiated with a 66MeV proton beam while the monitoring equipment observed any errors that had occurred. The results obtained indicated that all the implemented mitigation techniques tested on the VGA system improved the system’s capability of mitigating Single Event Upsets (SEU). The most effective mitigation technique was the OR-AND Multiplexer Single Event Transient (SET) filter technique. It was thus shown that mitigation techniques are viable options to prevent SEU in a VGA controller. The permanent SEU testing set-up which was designed and manufactured and was used to conduct the experiments, proved to be a practical option for further microelectronics testing at iThemba LABS.
- Full Text:
- Date Issued: 2015
Friction hydro pillar riveting process of Ti-6AI-4V titanium sheet
- Authors: Tsikayi, Davies Shamiso
- Date: 2015
- Subjects: Friction welding , Titanium alloys -- Welding , Sheet-metal
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/6357 , vital:21078
- Description: Mechanical fasteners are used extensively in the joining of two or more metal plates or sheets. Riveted joints have been the joints of choice mainly for the Aerospace Industry. However for this research, Friction Hydro Pillar Processing has been used to develop and characterise a new riveting technique termed Friction Hydro Pillar Riveting (FHPR). Two overlapping 3.17 mm Ti-6Al-4V sheets were joined together using Ø6 mm rivet which was friction processed. This research has focussed on the initial development of Friction Hydro Pillar Riveting thereby establishing a basic understanding of the influences of main process parameters, rotational speed and axial force - and also joint configurations. The results showed that with a decrease in the bottom hole chamfer angle, there was resulting overall increase in the rivet joint pull off strength. From the best performing joint configuration in pull off tests, shear tests were conducted whilst a blind hole FHPR joint was also done and tested in pull off and shear strength. The shear test fracture surfaces exhibited ductile failure. The microstructure of the joints was thus evaluated. From parent material, heat affected zone and to weld zone there was a variation in the microstructure analysed. The hardness profiles showed increased hardness in the weld zone which partly explained the shear results. The hardness increase was mainly due to grain refinement in the weld zone by the Friction Hydro Pillar Riveting process.
- Full Text:
- Date Issued: 2015
- Authors: Tsikayi, Davies Shamiso
- Date: 2015
- Subjects: Friction welding , Titanium alloys -- Welding , Sheet-metal
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/6357 , vital:21078
- Description: Mechanical fasteners are used extensively in the joining of two or more metal plates or sheets. Riveted joints have been the joints of choice mainly for the Aerospace Industry. However for this research, Friction Hydro Pillar Processing has been used to develop and characterise a new riveting technique termed Friction Hydro Pillar Riveting (FHPR). Two overlapping 3.17 mm Ti-6Al-4V sheets were joined together using Ø6 mm rivet which was friction processed. This research has focussed on the initial development of Friction Hydro Pillar Riveting thereby establishing a basic understanding of the influences of main process parameters, rotational speed and axial force - and also joint configurations. The results showed that with a decrease in the bottom hole chamfer angle, there was resulting overall increase in the rivet joint pull off strength. From the best performing joint configuration in pull off tests, shear tests were conducted whilst a blind hole FHPR joint was also done and tested in pull off and shear strength. The shear test fracture surfaces exhibited ductile failure. The microstructure of the joints was thus evaluated. From parent material, heat affected zone and to weld zone there was a variation in the microstructure analysed. The hardness profiles showed increased hardness in the weld zone which partly explained the shear results. The hardness increase was mainly due to grain refinement in the weld zone by the Friction Hydro Pillar Riveting process.
- Full Text:
- Date Issued: 2015
A sustainable water quality framework for South Africa towards 2050
- Authors: Osmond, Christopher John
- Date: 2015
- Subjects: Construction industry -- South Africa , Sustainable development -- South Africa , Water resources development -- South Africa , Water quality management -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/3255 , vital:20417
- Description: There are a wide range of issues that stem from inadequate access to, and the unsustainable management of water resources, which can lead to ecological and human crises (Gleik, 1998: 571). With the increasing demand for clean water for drinking and sanitation, coupled with population growth, aging infrastructure, and climate change, many countries face a complex set of threats when dealing with their water resources and the management thereof (Environmental Protection Agency, 2012: 4). South Africa‟s challenges are no different, if current trends in water management continue and government does not intervene with what has been an unequal society even in terms of the division of water, it will continue to lose ground in its development and sustaining of water resources (Ukwandu, 2009: 24 - 30). “The objective of managing the quantity, quality and reliability of the nation‟s water resources is to achieve optimum, long-term, environmentally sustainable social and economic benefit for society from their use.” (Principle 7 of the National Water Policy, Department of Water Affairs and Forestry, 1997: 20). The primary objective of this research is to develop a framework for water management and sustainable development by utilising a Causal Layered Analysis (CLA) to develop strategies for innovation in South Africa towards 2050. New rules and regulations have been adopted by local municipal divisions in South Africa to promote sustainable, environmentally friendly buildings and methods. It is therefore the aim of the research to establish ways in which water can be harvested and saved in a simple and innovative yet sustainable manner. The complexity of erecting structures has also increased with some sustainable measures in water management taking place, however the water issues in South Africa continue to grow and cause concern. Government therefore plays a pivotal role in ensuring that water is managed sustainably at not only harvesting and infrastructure level but also re-cycling level, where simple innovative strategies can be adopted. This paper further seeks to highlight the positive and negative impacts of implementing water management methods and strategies that can be adopted.
- Full Text:
- Date Issued: 2015
- Authors: Osmond, Christopher John
- Date: 2015
- Subjects: Construction industry -- South Africa , Sustainable development -- South Africa , Water resources development -- South Africa , Water quality management -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/3255 , vital:20417
- Description: There are a wide range of issues that stem from inadequate access to, and the unsustainable management of water resources, which can lead to ecological and human crises (Gleik, 1998: 571). With the increasing demand for clean water for drinking and sanitation, coupled with population growth, aging infrastructure, and climate change, many countries face a complex set of threats when dealing with their water resources and the management thereof (Environmental Protection Agency, 2012: 4). South Africa‟s challenges are no different, if current trends in water management continue and government does not intervene with what has been an unequal society even in terms of the division of water, it will continue to lose ground in its development and sustaining of water resources (Ukwandu, 2009: 24 - 30). “The objective of managing the quantity, quality and reliability of the nation‟s water resources is to achieve optimum, long-term, environmentally sustainable social and economic benefit for society from their use.” (Principle 7 of the National Water Policy, Department of Water Affairs and Forestry, 1997: 20). The primary objective of this research is to develop a framework for water management and sustainable development by utilising a Causal Layered Analysis (CLA) to develop strategies for innovation in South Africa towards 2050. New rules and regulations have been adopted by local municipal divisions in South Africa to promote sustainable, environmentally friendly buildings and methods. It is therefore the aim of the research to establish ways in which water can be harvested and saved in a simple and innovative yet sustainable manner. The complexity of erecting structures has also increased with some sustainable measures in water management taking place, however the water issues in South Africa continue to grow and cause concern. Government therefore plays a pivotal role in ensuring that water is managed sustainably at not only harvesting and infrastructure level but also re-cycling level, where simple innovative strategies can be adopted. This paper further seeks to highlight the positive and negative impacts of implementing water management methods and strategies that can be adopted.
- Full Text:
- Date Issued: 2015
Green procurement for municipal construction projects
- Authors: Maboza, Luthando Sithembele
- Date: 2015
- Subjects: Sustainable construction , Construction industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/3165 , vital:20407
- Description: The study is a qualitative investigation of the implementation of green procurement in the construction sector at Local Government level. The focus is on the Metropolitan Municipalities of EThekwini, Nelson Mandela Bay and City of Cape Town. For the purpose of realising an extended comparative perspective, an additional three smaller municipalities were also reviewed. Green procurement is the tool used by governments to source the supply of products and services that are environmentally friendly to counter the global problem of climate change. The study commences with the exposition of the aspects of green procurement from the basis of the enabling legal framework to the scholarly contribution from which the study can be predicated. It becomes apparent from this review of legislation that there is a scope within the existing body of legislation for the use of green procurement as an environmental tool. Scholarly work addresses adoption of green procurement and considers, inter alia, the Bottom-up Approach, the Top-down Approach, and the Procura + Milestones model. Literature indicates that development has a negative impact on the environment, which includes vegetation loss, illegal dumping, and greenhouse gas emissions. Further, the literature recommends green lifecycle design and production of construction projects to reduce the impact of construction on the environment. A systematic investigation of municipalities by means of interviews with relevant municipal officials involved with the procurement of products and services, infrastructure services and environmental affairs officials made it possible to identify factors that impact on the implementation of green procurement. The investigation finds that the major obstacles to green procurement are socio-economic challenges that confront municipalities, lack of policy, and lack of awareness. Recommendations include the proposal of initiatives that encourage and improve the implementation of green procurement. The study hopes to inspire innovation in the implementation of green procurement in the construction sector.
- Full Text:
- Date Issued: 2015
- Authors: Maboza, Luthando Sithembele
- Date: 2015
- Subjects: Sustainable construction , Construction industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/3165 , vital:20407
- Description: The study is a qualitative investigation of the implementation of green procurement in the construction sector at Local Government level. The focus is on the Metropolitan Municipalities of EThekwini, Nelson Mandela Bay and City of Cape Town. For the purpose of realising an extended comparative perspective, an additional three smaller municipalities were also reviewed. Green procurement is the tool used by governments to source the supply of products and services that are environmentally friendly to counter the global problem of climate change. The study commences with the exposition of the aspects of green procurement from the basis of the enabling legal framework to the scholarly contribution from which the study can be predicated. It becomes apparent from this review of legislation that there is a scope within the existing body of legislation for the use of green procurement as an environmental tool. Scholarly work addresses adoption of green procurement and considers, inter alia, the Bottom-up Approach, the Top-down Approach, and the Procura + Milestones model. Literature indicates that development has a negative impact on the environment, which includes vegetation loss, illegal dumping, and greenhouse gas emissions. Further, the literature recommends green lifecycle design and production of construction projects to reduce the impact of construction on the environment. A systematic investigation of municipalities by means of interviews with relevant municipal officials involved with the procurement of products and services, infrastructure services and environmental affairs officials made it possible to identify factors that impact on the implementation of green procurement. The investigation finds that the major obstacles to green procurement are socio-economic challenges that confront municipalities, lack of policy, and lack of awareness. Recommendations include the proposal of initiatives that encourage and improve the implementation of green procurement. The study hopes to inspire innovation in the implementation of green procurement in the construction sector.
- Full Text:
- Date Issued: 2015
Decision making for investment in residential real estate
- Authors: James, Matthew Gary Robert
- Date: 2015
- Subjects: Real estate investment -- Decision making Investment analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/10868 , vital:26831
- Description: Investment in residential real estate involves almost all members of the public at some stage of their lives, whether this be one's first home or the purchasing of one‟s first investment property. Understanding how to maximise the return on one's investment is something that can benefit the investor from before the investment is made until after the property has been sold, if it is sold at all. Literature surveys have concluded that there are a number of variables to consider when maximising the return on investment. As residential real estate is not a perfect science, there are guidelines and routes that are more beneficial to the investor depending on the current market, environment and economic standing. A survey was undertaken by members of the public that are involved in residential real estate investment, relative to the maximisation of the return on investment in residential real estate. The salient findings include: Investors in residential real estate spend more than average to extensive time prior, to investment researching the chosen residential real estate property; Investors in residential real estate perform a feasibility study before committing to the development whereas; Investors in residential real estate make use of financial advisors/valuers/estate agents or other investors' knowledge bases in deciding whether to invest in a residential property development; Investors in residential real estate believe that their degree of knowledge about the residential property market and residential property investments are average to very high. Investors in residential real estate somewhat agree that residential real estate investors do not effectively manage their investments. It was recommended that investors make use of help and guidance when investing in residential real estate, perform a feasibility study and ensure that they know their market before investing in a project. It was also noted that location plays a large role when deciding on an investment opportunity worth investing into. By creating awareness and ensuring that all methods and guidelines have been used to maximise the returns that their proposed residential real estate investment, investors can ensure a stronger, healthier cash flow and reap the highest possible benefits from their residential real estate portfolio.
- Full Text:
- Date Issued: 2015
- Authors: James, Matthew Gary Robert
- Date: 2015
- Subjects: Real estate investment -- Decision making Investment analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/10868 , vital:26831
- Description: Investment in residential real estate involves almost all members of the public at some stage of their lives, whether this be one's first home or the purchasing of one‟s first investment property. Understanding how to maximise the return on one's investment is something that can benefit the investor from before the investment is made until after the property has been sold, if it is sold at all. Literature surveys have concluded that there are a number of variables to consider when maximising the return on investment. As residential real estate is not a perfect science, there are guidelines and routes that are more beneficial to the investor depending on the current market, environment and economic standing. A survey was undertaken by members of the public that are involved in residential real estate investment, relative to the maximisation of the return on investment in residential real estate. The salient findings include: Investors in residential real estate spend more than average to extensive time prior, to investment researching the chosen residential real estate property; Investors in residential real estate perform a feasibility study before committing to the development whereas; Investors in residential real estate make use of financial advisors/valuers/estate agents or other investors' knowledge bases in deciding whether to invest in a residential property development; Investors in residential real estate believe that their degree of knowledge about the residential property market and residential property investments are average to very high. Investors in residential real estate somewhat agree that residential real estate investors do not effectively manage their investments. It was recommended that investors make use of help and guidance when investing in residential real estate, perform a feasibility study and ensure that they know their market before investing in a project. It was also noted that location plays a large role when deciding on an investment opportunity worth investing into. By creating awareness and ensuring that all methods and guidelines have been used to maximise the returns that their proposed residential real estate investment, investors can ensure a stronger, healthier cash flow and reap the highest possible benefits from their residential real estate portfolio.
- Full Text:
- Date Issued: 2015
An entrepreneurial framework for new venture property development projects
- Authors: Abrey, Mark Henry Shaw
- Date: 2015
- Subjects: Real estate development -- South Africa , Entrepreneurship -- South Africa , Land subdivision -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9709 , http://hdl.handle.net/10948/d1020162
- Description: The business of real estate is one of the largest suppliers of employment, and contributes significantly to the gross domestic product of numerous countries worldwide. It is, therefore, imperative that new real estate development entrepreneurs entering the market identify key competitiveness indicators in order to survive and ensure their success within an ever-changing market. However, property development is a complex process and considered to be 'too risky' Consequently, property development entrepreneurs lack the skills and expertise to effectively manage their business enterprises and the associated risks from project inception to completion, and commissioning. The study was conducted by means of a review of the related literature and by conducting an empirical study. The empirical study was conducted using a quantitative statistical approach by distributing research questionnaires to members falling within the sample population. The primary objective of the study was to develop an entrepreneurial framework for perceived success of new venture property development projects. A descriptive survey was conducted among professionals registered with the South African Property Owners Association (SAPOA) and property development practitioners within South Africa. The salient findings suggest that the following variables positively influence the perceived success of new venture property development projects: Entrepreneurial vision; Strategic management; Stakeholders‘ interests; Professional feasibility and viability reporting; Procurement; Communication; Consumer confidence; Risk management; Governance structures; Specialist advice; The entrepreneurial framework, and The project management body of knowledge (PMBOK). Furthermore, the following variables were identified in the empirical framework affecting the perceived success of new venture property development projects: Entrepreneurial Vision; Strategic Management; Stakeholders‘ Interest; Professional Feasibility and Viability Reporting; Procurement; Communication; Consumer Confidence; Risk Management; Governance Structures; Specialist Advice, and The Project Management Body of Knowledge (PMBOK). This study contributed to the South African property development body of knowledge by addressing the challenges faced by inexperienced entrepreneurs entering the property development market. Furthermore, this study aimed to improve the framework utilised by emerging property developers.
- Full Text:
- Date Issued: 2015
- Authors: Abrey, Mark Henry Shaw
- Date: 2015
- Subjects: Real estate development -- South Africa , Entrepreneurship -- South Africa , Land subdivision -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:9709 , http://hdl.handle.net/10948/d1020162
- Description: The business of real estate is one of the largest suppliers of employment, and contributes significantly to the gross domestic product of numerous countries worldwide. It is, therefore, imperative that new real estate development entrepreneurs entering the market identify key competitiveness indicators in order to survive and ensure their success within an ever-changing market. However, property development is a complex process and considered to be 'too risky' Consequently, property development entrepreneurs lack the skills and expertise to effectively manage their business enterprises and the associated risks from project inception to completion, and commissioning. The study was conducted by means of a review of the related literature and by conducting an empirical study. The empirical study was conducted using a quantitative statistical approach by distributing research questionnaires to members falling within the sample population. The primary objective of the study was to develop an entrepreneurial framework for perceived success of new venture property development projects. A descriptive survey was conducted among professionals registered with the South African Property Owners Association (SAPOA) and property development practitioners within South Africa. The salient findings suggest that the following variables positively influence the perceived success of new venture property development projects: Entrepreneurial vision; Strategic management; Stakeholders‘ interests; Professional feasibility and viability reporting; Procurement; Communication; Consumer confidence; Risk management; Governance structures; Specialist advice; The entrepreneurial framework, and The project management body of knowledge (PMBOK). Furthermore, the following variables were identified in the empirical framework affecting the perceived success of new venture property development projects: Entrepreneurial Vision; Strategic Management; Stakeholders‘ Interest; Professional Feasibility and Viability Reporting; Procurement; Communication; Consumer Confidence; Risk Management; Governance Structures; Specialist Advice, and The Project Management Body of Knowledge (PMBOK). This study contributed to the South African property development body of knowledge by addressing the challenges faced by inexperienced entrepreneurs entering the property development market. Furthermore, this study aimed to improve the framework utilised by emerging property developers.
- Full Text:
- Date Issued: 2015
The ethical conduct of new entry level emerging contractors
- Authors: Van Schalkwyk, Tanya Leonie
- Date: 2015
- Subjects: Construction industry -- Moral and ethical aspects , Building -- Moral and ethical aspects , Construction workers -- Professional ethics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/4932 , vital:20769
- Description: Ethics is not a new or modern discipline. It was developed thousands of years ago and still remains relevant today. Ethics is applied in all spheres of modern life from philosophy to business and religious environments and even around dinner table conversations. It is applicable to all areas of life. This research is aimed at investigating whether ethical conduct among new entry level emerging contractors can contribute to and ensure their sustainable competitiveness within the South African construction industry. This research is also aimed at determining whether education and knowledge of entrepreneurship, business, project and construction management and building contracts can contribute to new entry level emerging contractors’ ethical conduct and sustainable competitiveness. The literature reviewed and results of quantitative and qualitative research amongst professional consultants in South Africa formed the basis of the study. Ethics is a sensitive topic within the industry and therefor it is difficult to gather data directly from contractors, as they are reluctant to participate in fear of revealing their identities and having it negatively influencing their personal and business credentials. Therefor unbiased respondents who were not directly linked to emerging contractors and who were unafraid to give objective opinions were questioned. These unbiased respondents included consultants within the industry. The study revealed that ethics is an important factor in any business environment and that the correct application thereof can partially contribute to the sustainable competitiveness of new entry level emerging contractors and this in turn can promote the long term survival of a business. Furthermore, knowledge of good management practices and building contracts can contribute to a successfully run business. However, the average new entry level emerging contractor has insufficient experience and knowledge of the management of construction projects, as well as building contracts.
- Full Text:
- Date Issued: 2015
- Authors: Van Schalkwyk, Tanya Leonie
- Date: 2015
- Subjects: Construction industry -- Moral and ethical aspects , Building -- Moral and ethical aspects , Construction workers -- Professional ethics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/4932 , vital:20769
- Description: Ethics is not a new or modern discipline. It was developed thousands of years ago and still remains relevant today. Ethics is applied in all spheres of modern life from philosophy to business and religious environments and even around dinner table conversations. It is applicable to all areas of life. This research is aimed at investigating whether ethical conduct among new entry level emerging contractors can contribute to and ensure their sustainable competitiveness within the South African construction industry. This research is also aimed at determining whether education and knowledge of entrepreneurship, business, project and construction management and building contracts can contribute to new entry level emerging contractors’ ethical conduct and sustainable competitiveness. The literature reviewed and results of quantitative and qualitative research amongst professional consultants in South Africa formed the basis of the study. Ethics is a sensitive topic within the industry and therefor it is difficult to gather data directly from contractors, as they are reluctant to participate in fear of revealing their identities and having it negatively influencing their personal and business credentials. Therefor unbiased respondents who were not directly linked to emerging contractors and who were unafraid to give objective opinions were questioned. These unbiased respondents included consultants within the industry. The study revealed that ethics is an important factor in any business environment and that the correct application thereof can partially contribute to the sustainable competitiveness of new entry level emerging contractors and this in turn can promote the long term survival of a business. Furthermore, knowledge of good management practices and building contracts can contribute to a successfully run business. However, the average new entry level emerging contractor has insufficient experience and knowledge of the management of construction projects, as well as building contracts.
- Full Text:
- Date Issued: 2015
An organic rankine cycle heat engine using a rock thermal battery as the heat source
- Authors: Humm, Jason Christopher
- Date: 2015
- Subjects: Heat engineering Renewable energy sources
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/10960 , vital:26861
- Description: Organic Rankine cycles (ORC) have unique properties that are well suited to power generation from low grade heat sources. It is envisaged that a domestic scale ORC Heat Engine can be developed that will be able to run off heat stored in a solar charged rock thermal battery. The use of a thermal battery as the heat source for the ORC system will provide the user with electricity during the day and for a number of hours into the night. The concept presented consists of four key components: rock thermal battery, 1 kW scroll expander, condenser and working fluid pump.
- Full Text:
- Date Issued: 2015
- Authors: Humm, Jason Christopher
- Date: 2015
- Subjects: Heat engineering Renewable energy sources
- Language: English
- Type: Thesis , Masters , MTech
- Identifier: http://hdl.handle.net/10948/10960 , vital:26861
- Description: Organic Rankine cycles (ORC) have unique properties that are well suited to power generation from low grade heat sources. It is envisaged that a domestic scale ORC Heat Engine can be developed that will be able to run off heat stored in a solar charged rock thermal battery. The use of a thermal battery as the heat source for the ORC system will provide the user with electricity during the day and for a number of hours into the night. The concept presented consists of four key components: rock thermal battery, 1 kW scroll expander, condenser and working fluid pump.
- Full Text:
- Date Issued: 2015