A bitcoin framework : an alternative payment system for marginalized areas of South Africa using low-end mobile phones
- Authors: Dlamini, Nelisiwe Peaceness
- Date: 2016
- Subjects: Electronic funds transfers -- South Africa Bitcoin -- South Africa Mobile commerce -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11884 , vital:39115
- Description: The emergence of the cryptocurrency Bitcoin, has invoked the need for developing financial systems that can be used to transfer digital value. This would serve as a solution to developing countries especially the challenged ones, when it comes to accommodating the financial needs of the disadvantaged people. Moreover, it facilitates access to financial services to allow them to transact with ease. Numerous companies have taken advantage of the prevalence of mobile phones and introduced financial platforms to provide financial inclusion to disadvantaged people. Financial institutions and Mobile Network Operators (MNO) have developed platforms such as cell phone banking services, mobile money, mobile wallets, and electronic wallets that can be used to provide affordable financial services. Although this is the case, alternative platforms that are affordable and accessible through mobile phones are still required. Therefore, this study proposes a Bitcoin framework that can be used as an alternative platform through low-end mobile phones to provide access to financial services to the disadvantaged people in marginalized areas. To prove the concept of the proposed Bitcoin framework, a Mobile Bitcoin Wallet System (MBWS) prototype was developed, which allows a person using a low-end mobile phone with no intervening technology such as Internet or Bluetooth, to access a Bitcoin wallet by sending a Short Message Service (SMS). This enables Bitcoin to be accessed more easily and affordably by the people. Thus the developed prototype conceptualizes an alternative payment system or a payment method that can augment the existing payment methods. The MBWS is evaluated to assess if it can offer the services that other platforms offer by being compared to a cell-phone banking service. It was deployed on a computer connected to the Internet to enable a connection to the Bitcoin network and access to the blockchain which records all the transactions that take place in Bitcoin. Although this system provides access to the Bitcoin wallet, for it to be applied to areas where people require an alternative payment system, it still needs to be enhanced for such use. This includes scaling the system and adding more functions to it.
- Full Text:
- Date Issued: 2016
- Authors: Dlamini, Nelisiwe Peaceness
- Date: 2016
- Subjects: Electronic funds transfers -- South Africa Bitcoin -- South Africa Mobile commerce -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11884 , vital:39115
- Description: The emergence of the cryptocurrency Bitcoin, has invoked the need for developing financial systems that can be used to transfer digital value. This would serve as a solution to developing countries especially the challenged ones, when it comes to accommodating the financial needs of the disadvantaged people. Moreover, it facilitates access to financial services to allow them to transact with ease. Numerous companies have taken advantage of the prevalence of mobile phones and introduced financial platforms to provide financial inclusion to disadvantaged people. Financial institutions and Mobile Network Operators (MNO) have developed platforms such as cell phone banking services, mobile money, mobile wallets, and electronic wallets that can be used to provide affordable financial services. Although this is the case, alternative platforms that are affordable and accessible through mobile phones are still required. Therefore, this study proposes a Bitcoin framework that can be used as an alternative platform through low-end mobile phones to provide access to financial services to the disadvantaged people in marginalized areas. To prove the concept of the proposed Bitcoin framework, a Mobile Bitcoin Wallet System (MBWS) prototype was developed, which allows a person using a low-end mobile phone with no intervening technology such as Internet or Bluetooth, to access a Bitcoin wallet by sending a Short Message Service (SMS). This enables Bitcoin to be accessed more easily and affordably by the people. Thus the developed prototype conceptualizes an alternative payment system or a payment method that can augment the existing payment methods. The MBWS is evaluated to assess if it can offer the services that other platforms offer by being compared to a cell-phone banking service. It was deployed on a computer connected to the Internet to enable a connection to the Bitcoin network and access to the blockchain which records all the transactions that take place in Bitcoin. Although this system provides access to the Bitcoin wallet, for it to be applied to areas where people require an alternative payment system, it still needs to be enhanced for such use. This includes scaling the system and adding more functions to it.
- Full Text:
- Date Issued: 2016
A comparative analysis of mobile application development frameworks: A case study of mobile application development for water usage management in Alice and Fort Beaufort communities
- Authors: Manu, Kwabena
- Date: 2019
- Subjects: Mobile communication systems Cell phones Cloud computing
- Language: English
- Type: Thesis , Masters , MSc. (Computer Science)
- Identifier: http://hdl.handle.net/10353/14130 , vital:39853
- Description: Mobile phones have become an integral part of standard of living. Users and customers expect sensible and very useful applications in less time. In this competitive market, it is an enormous challenge to develop high performance mobile applications that might meet the expectations of end users. Despite the fact that development of new applications for each mobile operating system in short time is fairly an issue, mobile operating systems vendors are giving their best available resources for creating applications in additional convenient ways. These days, there is a common tendency to look for less complex and quicker solutions that could be used in the process of software development. Developers of a new mobile application have to undertake variety of selections and decisions, including the target platform as well as the development technology to utilize. Mobile application development frameworks contribute in solving this problem. Several frameworks have emerged, which we classify and evaluate their appropriateness. In order to compare existing development frameworks solutions in this research, we compiled a set of criteria to assess mobile application development approaches. In view on these criteria, we evaluated five frameworks that is, PhoneGap, Xamarin, App Inventor, Sencha Touch and DragonRad. For proof of concepts, the chosen framework from the five evaluated mobile development frameworks was used to develop application for water usage management. The research will equip mobile application developers to gain more insight into mobile development frameworks available, therefore helping them to choose the most appropriate framework for their project.
- Full Text:
- Date Issued: 2019
- Authors: Manu, Kwabena
- Date: 2019
- Subjects: Mobile communication systems Cell phones Cloud computing
- Language: English
- Type: Thesis , Masters , MSc. (Computer Science)
- Identifier: http://hdl.handle.net/10353/14130 , vital:39853
- Description: Mobile phones have become an integral part of standard of living. Users and customers expect sensible and very useful applications in less time. In this competitive market, it is an enormous challenge to develop high performance mobile applications that might meet the expectations of end users. Despite the fact that development of new applications for each mobile operating system in short time is fairly an issue, mobile operating systems vendors are giving their best available resources for creating applications in additional convenient ways. These days, there is a common tendency to look for less complex and quicker solutions that could be used in the process of software development. Developers of a new mobile application have to undertake variety of selections and decisions, including the target platform as well as the development technology to utilize. Mobile application development frameworks contribute in solving this problem. Several frameworks have emerged, which we classify and evaluate their appropriateness. In order to compare existing development frameworks solutions in this research, we compiled a set of criteria to assess mobile application development approaches. In view on these criteria, we evaluated five frameworks that is, PhoneGap, Xamarin, App Inventor, Sencha Touch and DragonRad. For proof of concepts, the chosen framework from the five evaluated mobile development frameworks was used to develop application for water usage management. The research will equip mobile application developers to gain more insight into mobile development frameworks available, therefore helping them to choose the most appropriate framework for their project.
- Full Text:
- Date Issued: 2019
A comparative economic analysis of small scale tobacco production under contract and non-contract farming : the case of Marondera rural district, Mashonaland East province, Zimbabwe
- Authors: Ruzhani, Freddy
- Date: 2015
- Subjects: Farms, Small -- Zimbabwe Tobacco industry -- Zimbabwe Farmers -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12653 , vital:39296
- Description: Constitutionalism and separation of powers is the most dynamic topic worldwide. Montesquieu, the French philosopher is credited with the doctrine of separation of powers. Various countries adopted the doctrine and modified it, in order to fit their systems of governments. The reason behind is that there is no universally recognized model of separation of powers or one size fit all. Countries apply this doctrine differently in a fashion that fits their domestic laws and constitutional requirements. Montesquieu gave a classic exposition and the rationale for separation of powers in one of his well-celebrated work “The Spirit of Laws”. The concept of separation of powers emerged premised on the theory that the arms of state namely, the judiciary, the legislature and the executive, should operate within their providence without one interfering with the other. From the South African perspective, the Constitution of South Africa of 1996 requires separation of powers even though it is not explicitly so stated in the text. This research examines the unique South African model of separation of powers and how the courts have navigated through it from the time the Constitution was promulgated. It seeks to establish whether or not a South African model of separation of powers has come to the fore. The research further examines the problem of interference amongst the arms of state and mechanism of checks and balances which can be applied to prevent or minimise such interference. In doing so, the study pursued a desktop survey of primary and secondary materials, including scientific literature, legislation, courts’ jurisprudence, and official documents. A comparative perspective was also made in order to learn from the experiences of other jurisdictions where the doctrine is applied. The findings reveal that South Africa has a unique model of separation of powers. The model was learned and enriched from various foreign jurisdictions. The courts have contributed enormously to this model, which contrive to be fluid and living.
- Full Text:
- Date Issued: 2015
- Authors: Ruzhani, Freddy
- Date: 2015
- Subjects: Farms, Small -- Zimbabwe Tobacco industry -- Zimbabwe Farmers -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12653 , vital:39296
- Description: Constitutionalism and separation of powers is the most dynamic topic worldwide. Montesquieu, the French philosopher is credited with the doctrine of separation of powers. Various countries adopted the doctrine and modified it, in order to fit their systems of governments. The reason behind is that there is no universally recognized model of separation of powers or one size fit all. Countries apply this doctrine differently in a fashion that fits their domestic laws and constitutional requirements. Montesquieu gave a classic exposition and the rationale for separation of powers in one of his well-celebrated work “The Spirit of Laws”. The concept of separation of powers emerged premised on the theory that the arms of state namely, the judiciary, the legislature and the executive, should operate within their providence without one interfering with the other. From the South African perspective, the Constitution of South Africa of 1996 requires separation of powers even though it is not explicitly so stated in the text. This research examines the unique South African model of separation of powers and how the courts have navigated through it from the time the Constitution was promulgated. It seeks to establish whether or not a South African model of separation of powers has come to the fore. The research further examines the problem of interference amongst the arms of state and mechanism of checks and balances which can be applied to prevent or minimise such interference. In doing so, the study pursued a desktop survey of primary and secondary materials, including scientific literature, legislation, courts’ jurisprudence, and official documents. A comparative perspective was also made in order to learn from the experiences of other jurisdictions where the doctrine is applied. The findings reveal that South Africa has a unique model of separation of powers. The model was learned and enriched from various foreign jurisdictions. The courts have contributed enormously to this model, which contrive to be fluid and living.
- Full Text:
- Date Issued: 2015
A Cost-Efficient Energy Management Model for ICT4D Platforms in Low Resource Communities
- Authors: Mbotoloshi, Dumisani
- Date: 2018
- Subjects: Information technology Communication in community development|
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/14538 , vital:39999
- Description: A couple of Information and Communication Technology (ICT) researches have been conducted in the rural communities of South Africa (SA). This has encouraged the development of ICT services such as e-government, e-commerce, e-judiciary, e-health, e-agriculture and many others. Proper ICT implementation has led to societal development, economic empowerment and sustainable communities. However, this is achieved after intensive planning and stakeholders‟ involvement. It is clear that ICTs require energy to function. Most significantly is the fact that a bulk of ICTs in low resource communities (LRC) are mainly donations and less consideration if any is made on their energy consumption. LRC are regions with minimum access to energy, clean water, educational facilities, health facilities, government facilities, technology etc. There have been debates on whether in LRC ICTs are consuming energy. Most ICTs have been deployed without much consideration on the required energy consumption. On the other hand, less research has been done on the sustainability of ICTs, especially considering that all ICT devices and related platforms rely on the availability of energy. There are a lot of possible low cost energy solutions that are available, which could be used to support ICTs in LRC. However, there are so many ICT services, devices and platforms that are lying idle and not been fully utilized in such areas due to the energy related issues. In most cases, ICT solutions in LRC are introduced mainly with Computer Science and Information Systems researchers, without including other key stakeholders like energy experts. The research presents a Cost Effecient Energy Management Model that could be used to assist ICT for Development (ICT4D) platforms or projects in LRC. Both qualitative and quantitative research methods were used within the Siyakhula Living Lab (SLL) in Eastern Cape (EC) Province of SA. Design Science theory is considered for the designing of the model. The SLL is an ICT project which is undertaken within the Dwesa, Bulembu and Alice rural communities. In this dissertation, Dwesa rural community is the chosen case. The surrounding schools in the communities have been used as the ICT point of contact. Interviews, questionnaires, literature v review, action research, focus group, experiments, formulas and evaluation were the specific methods used to conduct this research. Results show that ICTs deployed in the SLLs are mainly donations which consume much energy. The main source of energy use within the SLLs is electricity. From the three schools that were selected where ICTs have been deployed it was found that the electricity bill has increased enormously. This has caused some schools not to open the computer laboratories, which are supposed to be used by the community members. It was also found that there is no energy management plan or solution in place for the SLL resources. The findings show that ICTs within the SLL are been affected by energy related subjects, though the community has been willing to pay for electricity. The Cost Efficient Energy Management Model is proposed at the end of the dissertation. The model is targeted for ICT service providers and has five (5) main pillars i.e stakeholders‟ engagement, energy and ICT infrastructure, new business models, monitoring and evaluation, and finally awareness and training. The dissertation identified all the ICT resources and services at three selected schools within the SLL and drew up the energy consumption for each school. All schools indicated that there has been an increase in the electricity bill after the introduction of the SLL project. There was a clear indication that no energy expert was involved in the establishment of the SLLs. The dissertation indicates that there is a need for renewable source of energy for ICTs to improve service delivery in LRC. ICT service providers should consider energy subjects when planning for development of such solutions in LRC. This research focuses on designing a low cost ICT energy model to inform on ICTs energy consumption in LRC. It further outlines the possible ICT energy solutions that could be used to benefit targeted communities.
- Full Text:
- Date Issued: 2018
- Authors: Mbotoloshi, Dumisani
- Date: 2018
- Subjects: Information technology Communication in community development|
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/14538 , vital:39999
- Description: A couple of Information and Communication Technology (ICT) researches have been conducted in the rural communities of South Africa (SA). This has encouraged the development of ICT services such as e-government, e-commerce, e-judiciary, e-health, e-agriculture and many others. Proper ICT implementation has led to societal development, economic empowerment and sustainable communities. However, this is achieved after intensive planning and stakeholders‟ involvement. It is clear that ICTs require energy to function. Most significantly is the fact that a bulk of ICTs in low resource communities (LRC) are mainly donations and less consideration if any is made on their energy consumption. LRC are regions with minimum access to energy, clean water, educational facilities, health facilities, government facilities, technology etc. There have been debates on whether in LRC ICTs are consuming energy. Most ICTs have been deployed without much consideration on the required energy consumption. On the other hand, less research has been done on the sustainability of ICTs, especially considering that all ICT devices and related platforms rely on the availability of energy. There are a lot of possible low cost energy solutions that are available, which could be used to support ICTs in LRC. However, there are so many ICT services, devices and platforms that are lying idle and not been fully utilized in such areas due to the energy related issues. In most cases, ICT solutions in LRC are introduced mainly with Computer Science and Information Systems researchers, without including other key stakeholders like energy experts. The research presents a Cost Effecient Energy Management Model that could be used to assist ICT for Development (ICT4D) platforms or projects in LRC. Both qualitative and quantitative research methods were used within the Siyakhula Living Lab (SLL) in Eastern Cape (EC) Province of SA. Design Science theory is considered for the designing of the model. The SLL is an ICT project which is undertaken within the Dwesa, Bulembu and Alice rural communities. In this dissertation, Dwesa rural community is the chosen case. The surrounding schools in the communities have been used as the ICT point of contact. Interviews, questionnaires, literature v review, action research, focus group, experiments, formulas and evaluation were the specific methods used to conduct this research. Results show that ICTs deployed in the SLLs are mainly donations which consume much energy. The main source of energy use within the SLLs is electricity. From the three schools that were selected where ICTs have been deployed it was found that the electricity bill has increased enormously. This has caused some schools not to open the computer laboratories, which are supposed to be used by the community members. It was also found that there is no energy management plan or solution in place for the SLL resources. The findings show that ICTs within the SLL are been affected by energy related subjects, though the community has been willing to pay for electricity. The Cost Efficient Energy Management Model is proposed at the end of the dissertation. The model is targeted for ICT service providers and has five (5) main pillars i.e stakeholders‟ engagement, energy and ICT infrastructure, new business models, monitoring and evaluation, and finally awareness and training. The dissertation identified all the ICT resources and services at three selected schools within the SLL and drew up the energy consumption for each school. All schools indicated that there has been an increase in the electricity bill after the introduction of the SLL project. There was a clear indication that no energy expert was involved in the establishment of the SLLs. The dissertation indicates that there is a need for renewable source of energy for ICTs to improve service delivery in LRC. ICT service providers should consider energy subjects when planning for development of such solutions in LRC. This research focuses on designing a low cost ICT energy model to inform on ICTs energy consumption in LRC. It further outlines the possible ICT energy solutions that could be used to benefit targeted communities.
- Full Text:
- Date Issued: 2018
A derivation of the the black-scholes equation using martingales
- Authors: Nyarko , Ebenezer Narh
- Date: 2018
- Subjects: Mathematical models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14572 , vital:40016
- Description: This work focuses on the application of stochastic differential equations, with martingales, in finance. The emphasis is on the derivation of the Black-Scholes model for the valuation of options. A theoretical framework in stochastic analysis, together with Itô calculus (Kiyoshi Itô), is explored. The Girsanov Theorem is applied in order to transform a modelled stochastic equation based, on predetermined stock and bond prices, into equivalent martingale measures. A replication strategy is then adopted to solve the two equations analytically, by finding the natural logarithm of the expectation of the solution to the stochastic models. We finally compute the resulting solution based on a standard, normal distribution to get the desired outcome of the Black-Scholes model.
- Full Text:
- Date Issued: 2018
- Authors: Nyarko , Ebenezer Narh
- Date: 2018
- Subjects: Mathematical models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14572 , vital:40016
- Description: This work focuses on the application of stochastic differential equations, with martingales, in finance. The emphasis is on the derivation of the Black-Scholes model for the valuation of options. A theoretical framework in stochastic analysis, together with Itô calculus (Kiyoshi Itô), is explored. The Girsanov Theorem is applied in order to transform a modelled stochastic equation based, on predetermined stock and bond prices, into equivalent martingale measures. A replication strategy is then adopted to solve the two equations analytically, by finding the natural logarithm of the expectation of the solution to the stochastic models. We finally compute the resulting solution based on a standard, normal distribution to get the desired outcome of the Black-Scholes model.
- Full Text:
- Date Issued: 2018
A Model for Intrusion Detection in IoT using Machine Learning
- Authors: Nkala, Junior Ruddy
- Date: 2019
- Subjects: Internet of things
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/17180 , vital:40863
- Description: The Internet of Things is an open and comprehensive global network of intelligent objects that have the capacity to auto-organize, share information, data and resources. There are currently over a billion devices connected to the Internet, and this number increases by the day. While these devices make our life easier, safer and healthier, they are expanding the number of attack targets vulnerable to cyber-attacks from potential hackers and malicious software. Therefore, protecting these devices from adversaries and unauthorized access and modification is very important. The purpose of this study is to develop a secure lightweight intrusion and anomaly detection model for IoT to help detect threats in the environment. We propose the use of data mining and machine learning algorithms as a classification technique for detecting abnormal or malicious traffic transmitted between devices due to potential attacks such as DoS, Man-In-Middle and Flooding attacks at the application level. This study makes use of two robust machine learning algorithms, namely the C4.5 Decision Trees and K-means clustering to develop an anomaly detection model. MATLAB Math Simulator was used for implementation. The study conducts a series of experiments in detecting abnormal data and normal data in a dataset that contains gas concentration readings from a number of sensors deployed in an Italian city over a year. Thereafter we examined the classification performance in terms of accuracy of our proposed anomaly detection model. Results drawn from the experiments conducted indicate that the size of the training sample improves classification ability of the proposed model. Our findings noted that the choice of discretization algorithm does matter in the quest for optimal classification performance. The proposed model proved accurate in detecting anomalies in IoT, and classifying between normal and abnormal data. The proposed model has a classification accuracy of 96.51% which proved to be higher compared to other algorithms such as the Naïve Bayes. The model proved to be lightweight and efficient in-terms of being faster at training and testing as compared to Artificial Neural Networks. The conclusions drawn from this research are a perspective from a novice machine learning researcher with valuable recommendations that ensure optimal classification of normal and abnormal IoT data.
- Full Text:
- Date Issued: 2019
- Authors: Nkala, Junior Ruddy
- Date: 2019
- Subjects: Internet of things
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/17180 , vital:40863
- Description: The Internet of Things is an open and comprehensive global network of intelligent objects that have the capacity to auto-organize, share information, data and resources. There are currently over a billion devices connected to the Internet, and this number increases by the day. While these devices make our life easier, safer and healthier, they are expanding the number of attack targets vulnerable to cyber-attacks from potential hackers and malicious software. Therefore, protecting these devices from adversaries and unauthorized access and modification is very important. The purpose of this study is to develop a secure lightweight intrusion and anomaly detection model for IoT to help detect threats in the environment. We propose the use of data mining and machine learning algorithms as a classification technique for detecting abnormal or malicious traffic transmitted between devices due to potential attacks such as DoS, Man-In-Middle and Flooding attacks at the application level. This study makes use of two robust machine learning algorithms, namely the C4.5 Decision Trees and K-means clustering to develop an anomaly detection model. MATLAB Math Simulator was used for implementation. The study conducts a series of experiments in detecting abnormal data and normal data in a dataset that contains gas concentration readings from a number of sensors deployed in an Italian city over a year. Thereafter we examined the classification performance in terms of accuracy of our proposed anomaly detection model. Results drawn from the experiments conducted indicate that the size of the training sample improves classification ability of the proposed model. Our findings noted that the choice of discretization algorithm does matter in the quest for optimal classification performance. The proposed model proved accurate in detecting anomalies in IoT, and classifying between normal and abnormal data. The proposed model has a classification accuracy of 96.51% which proved to be higher compared to other algorithms such as the Naïve Bayes. The model proved to be lightweight and efficient in-terms of being faster at training and testing as compared to Artificial Neural Networks. The conclusions drawn from this research are a perspective from a novice machine learning researcher with valuable recommendations that ensure optimal classification of normal and abnormal IoT data.
- Full Text:
- Date Issued: 2019
A study of the geology of the Vaalbank and Lady Frere areas in the Karoo Basin of South Africa using gravity, magnetic and gamma-ray spectrometry data: implications of groundwater potential
- Khalimashe, Sinesihle, Gwavava, Oswald
- Authors: Khalimashe, Sinesihle , Gwavava, Oswald
- Date: 2020
- Subjects: Gamma ray astronomy
- Language: English
- Type: Thesis , Masters , MSc (Geology)
- Identifier: http://hdl.handle.net/10353/11983 , vital:39124
- Description: The Vaalbank and Lady Frere areas belong to the Elliot, Molteno and Burgersdorp Formations, that are part of the sedimentary succession of the Beaufort Group in the Karoo Basin of South Africa. There is Quaternary alluvium covering the mudstone, sandstone and shale rocks of the Beaufort Group. Dolerite and gabbro sills of the Karoo age have intruded the whole area. A number of investigations were carried out for the study namely field observations, petrographic, X-ray diffraction, airborne gamma-ray spectrometry, aeromagnetic and gravity analyses. Twenty four rock samples were collected in the field from fresh outcrops of the Karoo dolerites, Burgersdorp and Molteno formations. The measured densities and porosities show that the Karoo dolerite suite has the highest average dry density of 2.771 g/cm3 and the lowest average porosity of 3%. The Burgersdorp Formation has an intermediate average density of 2.458 g/cm3 and an intermediate average porosity of 5.4%. The Molteno Formation has the lowest average density of 2.190 g/cm3 and the highest average porosity of 14.5%. Petrographic and geochemical investigations were carried on 19 rocks samples collected in the field to determine the mineralogy character using microscopic and XRD analyses. Both petrographic and X-ray diffraction analyses revealed that the sandstones of the study area are composed of quartz as their primary mineral and feldspars as the secondary mineral. The dolerite consists of euhedral structured minerals such as magnetite, pyroxene, plagioclase and amphibole. The gamma ray maps show high spectrometric values are associated with the Burgersdorp Formation, alluvium cover and dolerite dykes. The low spectrometric values are associated with dolerite sills and ring complexes. The boundaries of the sill/ring complexes are clearly delineated by the K/U ratio and ternary maps. The magnetic maps show ring like patterns of magnetic high anomalies that are due to the sills/ring complexes whilst the numerous, narrow, linear magnetic highs are due to faults and dolerite dyke swarms. The majority of the dykes trend in a NW-SE direction and a few dykes are in a NE-SE direction. The magnetic power spectrum indicates four depths of the magnetic sources at average depths of 0.13 km, 1.60 km, 2.83 km and 12.40 km. The magnetic depth iii slices maps show that both the circular/ring like and linear anomalies extend from shallow to deeper depth of 12.4 km. The gravity map is dominated by a long wavelength gravity anomaly that increases from about -120 mGals in the northwestern corner of the study area to -110 mGals in the southeastern corner of the study area. Results from 2½D gravity modelling show that this long wavelength anomaly is due to a horizontal Moho at a depth of 47 km in the study area, which shallows outside the study area near the coast. Superimposed on it are short wavelength gravity anomalies due to low density sediments and high density dolerite intrusions. The simple 2½D models generated from five profiles traversing the study area reveal that the sediments of the Karoo Supergroup extend from the surface down to a depth 5 km below sea level attaining a maximum thickness of about 6½ km. These sediments are dykes, sills and ring complexes. The dykes and sills/ring complexes identified from gamma ray spectrometry, magnetic and gravity data results are likely to be associated with fractures, joints, cracks and fissures in the host rocks, which form preferential pathways for groundwater transmission. Hence, they could be suitable targets for groundwater.
- Full Text:
- Date Issued: 2020
- Authors: Khalimashe, Sinesihle , Gwavava, Oswald
- Date: 2020
- Subjects: Gamma ray astronomy
- Language: English
- Type: Thesis , Masters , MSc (Geology)
- Identifier: http://hdl.handle.net/10353/11983 , vital:39124
- Description: The Vaalbank and Lady Frere areas belong to the Elliot, Molteno and Burgersdorp Formations, that are part of the sedimentary succession of the Beaufort Group in the Karoo Basin of South Africa. There is Quaternary alluvium covering the mudstone, sandstone and shale rocks of the Beaufort Group. Dolerite and gabbro sills of the Karoo age have intruded the whole area. A number of investigations were carried out for the study namely field observations, petrographic, X-ray diffraction, airborne gamma-ray spectrometry, aeromagnetic and gravity analyses. Twenty four rock samples were collected in the field from fresh outcrops of the Karoo dolerites, Burgersdorp and Molteno formations. The measured densities and porosities show that the Karoo dolerite suite has the highest average dry density of 2.771 g/cm3 and the lowest average porosity of 3%. The Burgersdorp Formation has an intermediate average density of 2.458 g/cm3 and an intermediate average porosity of 5.4%. The Molteno Formation has the lowest average density of 2.190 g/cm3 and the highest average porosity of 14.5%. Petrographic and geochemical investigations were carried on 19 rocks samples collected in the field to determine the mineralogy character using microscopic and XRD analyses. Both petrographic and X-ray diffraction analyses revealed that the sandstones of the study area are composed of quartz as their primary mineral and feldspars as the secondary mineral. The dolerite consists of euhedral structured minerals such as magnetite, pyroxene, plagioclase and amphibole. The gamma ray maps show high spectrometric values are associated with the Burgersdorp Formation, alluvium cover and dolerite dykes. The low spectrometric values are associated with dolerite sills and ring complexes. The boundaries of the sill/ring complexes are clearly delineated by the K/U ratio and ternary maps. The magnetic maps show ring like patterns of magnetic high anomalies that are due to the sills/ring complexes whilst the numerous, narrow, linear magnetic highs are due to faults and dolerite dyke swarms. The majority of the dykes trend in a NW-SE direction and a few dykes are in a NE-SE direction. The magnetic power spectrum indicates four depths of the magnetic sources at average depths of 0.13 km, 1.60 km, 2.83 km and 12.40 km. The magnetic depth iii slices maps show that both the circular/ring like and linear anomalies extend from shallow to deeper depth of 12.4 km. The gravity map is dominated by a long wavelength gravity anomaly that increases from about -120 mGals in the northwestern corner of the study area to -110 mGals in the southeastern corner of the study area. Results from 2½D gravity modelling show that this long wavelength anomaly is due to a horizontal Moho at a depth of 47 km in the study area, which shallows outside the study area near the coast. Superimposed on it are short wavelength gravity anomalies due to low density sediments and high density dolerite intrusions. The simple 2½D models generated from five profiles traversing the study area reveal that the sediments of the Karoo Supergroup extend from the surface down to a depth 5 km below sea level attaining a maximum thickness of about 6½ km. These sediments are dykes, sills and ring complexes. The dykes and sills/ring complexes identified from gamma ray spectrometry, magnetic and gravity data results are likely to be associated with fractures, joints, cracks and fissures in the host rocks, which form preferential pathways for groundwater transmission. Hence, they could be suitable targets for groundwater.
- Full Text:
- Date Issued: 2020
A study of the southwestern Karoo basin in South Africa using magnetic and gravity data
- Authors: Nxantsiya, Zusakhe
- Date: 2017
- Subjects: Groundwater -- South Africa -- Karoo
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14043 , vital:39800
- Description: The early efforts of Booth, Johnson, Rubidge, Catuneanu, de Wit, Chevallier, Stankiewicz, Weckmann and many other scientists in studying the Karoo Supergroup has led to comprehensive documentation of the geology on the main Karoo Basin with regards to understanding the age, sedimentology, sedimentary facies and depositional environments. In spite of these studies, the subsurface structure, variations in thickness of various formations in large parts of the basin, the location and orientation of subsurface dolerite intrusions, and the depth to magnetic and gravity sources remains poorly documented. A geological study with the aid of geophysical techniques, magnetic and gravity, was conducted in the southwestern part of the main Karoo Basin. The objectives of the study were to construct numerous models of the main basin that image the crust to a depth of 45 km, to determine thicknesses of various formations, to relate observed geophysical anomalies with geological bodies and lineaments, to estimate the depth of existing anomalous bodies, to determine densities and porosity of various formations, as well as to determine the mineralogy of various rocks in the Karoo Basin. In total, seventy one rock samples were collected in the main Karoo Basin for density and mineralogical studies. The density results showed that the Beaufort and Ecca Group rocks have the low mean density of 2.490 g/cm3 amongst the rocks while the dolerite intrusions have the highest mean density of 2.697 g/cm3. The porosities of various rocks determined from the measured rock densities revealed that the Ecca Group shales, particularly the Whitehill Formation has the highest porosity of 4.5percent, while the Collingham Formation has the least porosity of 1.4 percent amongst the Ecca Group shales. Mineralogical analysis of seventeen XRD samples and 26 thin sections indicate that quartz, kaolinite, and plagioclase occur as the major mineral in most sandstones and shales in the Karoo Basin, while the pyrophyllite, smectite, and talc occur as minor minerals. Other mineral constituents include, calcite, mica, and amphibole. The 2½ dimensional (2½ D) gravity modelling along seven selected profiles, across the Beattie Magnetic Anomaly (BMA), revealed that the Ecca Group sediments, a target for shale gas exploration in the Karoo, occurs within a depth range of 0 - 4000 m from the surface. The basin deepens to a depth of 4600 m in the southwestern region, near the front of the Cape Fold Belt. It was observed as well that the Karoo dolerite sills are connected at depths and are mostly concentrated at the centre, the deepest part of the basin with some having saucer shape - like structure. These observations correspond well with the borehole data from AB 1/65 and QU 1/65 presented in Linol and de Wit (2016). Thickness isochore maps that were extracted from the gravity models indicate that the Ecca Group, which is the main target for hydrocarbon exploration, thickens to the south away from the centre of the basin and reaches thicknesses of greater than 3680 m. The Beaufort Group proves to be the thickest succession in the Karoo Basin with an estimated thickness of up to 6046 m. Constructed geophysical maps with the geology overlain reveal that most magnetic anomalies are due to dolerite intrusions, while gravity lows are due to less dense shales of the Ecca Group. The depth slices of magnetic data indicate that near surface magnetic bodies occur within the depth of 42 m from the surface whereas deep seated ones occur as deep as 9488 m and possibly deeper. Gravity depth slices reveal signatures that are predominant at depth of 2403 m are of short wavelength and are mainly lineaments and circular structures. They ultimately disappear at depth of 7120 m. The depth slices further indicate that the intensity of both magnetic and gravity long wavelength signatures become stronger with increasing depths.
- Full Text:
- Date Issued: 2017
- Authors: Nxantsiya, Zusakhe
- Date: 2017
- Subjects: Groundwater -- South Africa -- Karoo
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14043 , vital:39800
- Description: The early efforts of Booth, Johnson, Rubidge, Catuneanu, de Wit, Chevallier, Stankiewicz, Weckmann and many other scientists in studying the Karoo Supergroup has led to comprehensive documentation of the geology on the main Karoo Basin with regards to understanding the age, sedimentology, sedimentary facies and depositional environments. In spite of these studies, the subsurface structure, variations in thickness of various formations in large parts of the basin, the location and orientation of subsurface dolerite intrusions, and the depth to magnetic and gravity sources remains poorly documented. A geological study with the aid of geophysical techniques, magnetic and gravity, was conducted in the southwestern part of the main Karoo Basin. The objectives of the study were to construct numerous models of the main basin that image the crust to a depth of 45 km, to determine thicknesses of various formations, to relate observed geophysical anomalies with geological bodies and lineaments, to estimate the depth of existing anomalous bodies, to determine densities and porosity of various formations, as well as to determine the mineralogy of various rocks in the Karoo Basin. In total, seventy one rock samples were collected in the main Karoo Basin for density and mineralogical studies. The density results showed that the Beaufort and Ecca Group rocks have the low mean density of 2.490 g/cm3 amongst the rocks while the dolerite intrusions have the highest mean density of 2.697 g/cm3. The porosities of various rocks determined from the measured rock densities revealed that the Ecca Group shales, particularly the Whitehill Formation has the highest porosity of 4.5percent, while the Collingham Formation has the least porosity of 1.4 percent amongst the Ecca Group shales. Mineralogical analysis of seventeen XRD samples and 26 thin sections indicate that quartz, kaolinite, and plagioclase occur as the major mineral in most sandstones and shales in the Karoo Basin, while the pyrophyllite, smectite, and talc occur as minor minerals. Other mineral constituents include, calcite, mica, and amphibole. The 2½ dimensional (2½ D) gravity modelling along seven selected profiles, across the Beattie Magnetic Anomaly (BMA), revealed that the Ecca Group sediments, a target for shale gas exploration in the Karoo, occurs within a depth range of 0 - 4000 m from the surface. The basin deepens to a depth of 4600 m in the southwestern region, near the front of the Cape Fold Belt. It was observed as well that the Karoo dolerite sills are connected at depths and are mostly concentrated at the centre, the deepest part of the basin with some having saucer shape - like structure. These observations correspond well with the borehole data from AB 1/65 and QU 1/65 presented in Linol and de Wit (2016). Thickness isochore maps that were extracted from the gravity models indicate that the Ecca Group, which is the main target for hydrocarbon exploration, thickens to the south away from the centre of the basin and reaches thicknesses of greater than 3680 m. The Beaufort Group proves to be the thickest succession in the Karoo Basin with an estimated thickness of up to 6046 m. Constructed geophysical maps with the geology overlain reveal that most magnetic anomalies are due to dolerite intrusions, while gravity lows are due to less dense shales of the Ecca Group. The depth slices of magnetic data indicate that near surface magnetic bodies occur within the depth of 42 m from the surface whereas deep seated ones occur as deep as 9488 m and possibly deeper. Gravity depth slices reveal signatures that are predominant at depth of 2403 m are of short wavelength and are mainly lineaments and circular structures. They ultimately disappear at depth of 7120 m. The depth slices further indicate that the intensity of both magnetic and gravity long wavelength signatures become stronger with increasing depths.
- Full Text:
- Date Issued: 2017
Accessibility of agricultural information by smallholder farmers in Amatole District Municipality: Nexus between agricultural extension services and the library
- Authors: Sigigaba, Masimthembe
- Date: 2020
- Subjects: Farms, Small
- Language: English
- Type: Thesis , Masters , M Agric (Agric Extension)
- Identifier: http://hdl.handle.net/10353/18849 , vital:42870
- Description: Accessibility to relevant, accurate and timely information remains vital in farming. For farmers to improve their productivity they depend on access to pertinent agricultural information. Such information updated them about new agricultural technologies, climate change, new cultivars, access to market and access to financial assistance. These types of information help farmers in decision making regarding their farming. Agricultural extension officers remain a reliable source where farmers could obtain relevant agricultural information. Community libraries are also channels that could be used by agricultural extension officers to complement their work of providing farmers with information. Thus, the study sought to assess linkage between these two institutions to provide farmers with information. A positivism paradigm with quantitative research approach were adopted in the study. Smallholder farmers (169), agricultural extension officers (5) and librarians (15) were the unit of analysis. A semi-structured questionnaire was used for data collection and SPSS software for analysis. Findings revealed that, agricultural extension officers mostly utilise interpersonal channels that include demonstrations, group meetings and face-to-face interaction to provide farmers with information. Community libraries were found to be non-utilised by extension services and also by farmers. Farmers were of the perception that libraries are meant for educated people. It was also discovered that community libraries have information on agriculture that only targets learners who are taking agriculture in school as a subject. There was no existing linkage between agricultural extension services and community libraries working together to provide farmers with pertinent agricultural information that can help them improve productivity
- Full Text:
- Date Issued: 2020
- Authors: Sigigaba, Masimthembe
- Date: 2020
- Subjects: Farms, Small
- Language: English
- Type: Thesis , Masters , M Agric (Agric Extension)
- Identifier: http://hdl.handle.net/10353/18849 , vital:42870
- Description: Accessibility to relevant, accurate and timely information remains vital in farming. For farmers to improve their productivity they depend on access to pertinent agricultural information. Such information updated them about new agricultural technologies, climate change, new cultivars, access to market and access to financial assistance. These types of information help farmers in decision making regarding their farming. Agricultural extension officers remain a reliable source where farmers could obtain relevant agricultural information. Community libraries are also channels that could be used by agricultural extension officers to complement their work of providing farmers with information. Thus, the study sought to assess linkage between these two institutions to provide farmers with information. A positivism paradigm with quantitative research approach were adopted in the study. Smallholder farmers (169), agricultural extension officers (5) and librarians (15) were the unit of analysis. A semi-structured questionnaire was used for data collection and SPSS software for analysis. Findings revealed that, agricultural extension officers mostly utilise interpersonal channels that include demonstrations, group meetings and face-to-face interaction to provide farmers with information. Community libraries were found to be non-utilised by extension services and also by farmers. Farmers were of the perception that libraries are meant for educated people. It was also discovered that community libraries have information on agriculture that only targets learners who are taking agriculture in school as a subject. There was no existing linkage between agricultural extension services and community libraries working together to provide farmers with pertinent agricultural information that can help them improve productivity
- Full Text:
- Date Issued: 2020
Adol-Safety: A Framework for Empowering Parents to be Aware of Social Network Threats Affecting Adolescents
- Mjoli, Phumelela, Shibeshi, Z
- Authors: Mjoli, Phumelela , Shibeshi, Z
- Date: 2020
- Subjects: Social networks Social media|
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/12016 , vital:39127
- Description: The use of social networks has grown so much that adolescents have become active members of various social networks such as Twitter, Facebook, and Instagram, etc. The gradual change in how people choose to communicate, socialize and share ideas today has influenced adolescents to an extent that they find themselves wanting to engage more on social networks than they really should due to peer pressure. Whenever a person joins social networks or browses the Internet, they by default are exposed and become vulnerable to many cyber threats. Cyber threats are driven by users that have negative intentions on the Internet or social networks. Adolescents are no exception to these cyber threats. The findings of this research reveal that threats such as cyberbullying, harassment, and online predators to name a few are often designed to abuse and affect adolescents). Therefore, this research aims to prevent such threats from prevailing by empowering parents to be aware of the threats that affect their adolescents in an online environment, which typically includes social networks. To achieve this, this research starts by investigating the cyber threats that affect adolescents and then explores ways that can be used to empower parents. A framework is developed to handle this. The framework includes strategies that parents can adopt and ways in which safety on social networks can be increased, as well as guidelines that can be followed in order to prevent cyber threats. The framework also aims to enhance a parent-child relationship that can help in preventing social network threats. Lastly, the framework is implemented as a knowledgesharing website that can be used by parents to receive and give an insight into social network threats that influence adolescents on social networks.
- Full Text:
- Date Issued: 2020
- Authors: Mjoli, Phumelela , Shibeshi, Z
- Date: 2020
- Subjects: Social networks Social media|
- Language: English
- Type: Thesis , Masters , MSc (Computer Science )
- Identifier: http://hdl.handle.net/10353/12016 , vital:39127
- Description: The use of social networks has grown so much that adolescents have become active members of various social networks such as Twitter, Facebook, and Instagram, etc. The gradual change in how people choose to communicate, socialize and share ideas today has influenced adolescents to an extent that they find themselves wanting to engage more on social networks than they really should due to peer pressure. Whenever a person joins social networks or browses the Internet, they by default are exposed and become vulnerable to many cyber threats. Cyber threats are driven by users that have negative intentions on the Internet or social networks. Adolescents are no exception to these cyber threats. The findings of this research reveal that threats such as cyberbullying, harassment, and online predators to name a few are often designed to abuse and affect adolescents). Therefore, this research aims to prevent such threats from prevailing by empowering parents to be aware of the threats that affect their adolescents in an online environment, which typically includes social networks. To achieve this, this research starts by investigating the cyber threats that affect adolescents and then explores ways that can be used to empower parents. A framework is developed to handle this. The framework includes strategies that parents can adopt and ways in which safety on social networks can be increased, as well as guidelines that can be followed in order to prevent cyber threats. The framework also aims to enhance a parent-child relationship that can help in preventing social network threats. Lastly, the framework is implemented as a knowledgesharing website that can be used by parents to receive and give an insight into social network threats that influence adolescents on social networks.
- Full Text:
- Date Issued: 2020
Aeolian processes and landforms at Mesrug on sub-Antarctic Marion Island
- Authors: Nguna, Abuyiselwe Athandile
- Date: 2019
- Subjects: Eolian processes Sediments (Geology)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/17095 , vital:40848
- Description: Recent observations have recognised the increasing role of aeolian processes as a geomorphic agent on sub-Antarctic Marion Island. This study presents the first long-term data on aeolian processes and dynamics at Mesrug (46° 56’ 41”S; 37° 49’ 59”E) on subAntarctic Marion Island. An intensive and high-resolution (five-minute interval) environmental monitoring campaign was initiated using Pace Scientific XR5 data loggers while aeolian transported sediments were collected using Big Spring Number Eight (BSNE) sediment traps at four different heights above the ground. The aeolian features at Mesrug is identified as mega-ripples and is essentially an erosional feature, while annual sediment flux at 0.05 m height were calculated as 2.29 kg cm-2 y -1 . Spatial data based on a two-year survey showed that the entire surface of the study area have lowered by deflation while the ripples shifted slightly eastward (down-wind). Furthermore, the site lost 3.4 m3 of sediment between these two surveys with an average of 0.75 cm per 1 m2 across the site which has an area of 454 m2 . The study suggest that the relatively large particle size of surface sediments on Marion Island is a major contributor to the low annual aeolian sediment flux. From the AWS data it is clear that high wind speeds are frequent at Mesrug and the high wind speeds facilitating sediment movement. Sediment supply is the limiting factor of aeolian sediment transport, but even though the perennial wetness experienced on the island is not a major limiting factor to sediment flux, it may influence rate of movement. The predominant wind direction at the study site is from the south-west but maximum wind velocities are from the north-west. The data from the wind-aspirated BSNE sediment traps, indicate that sediment movement occurs closest to the surface and weight of sediment moved as well as size of particles decreases vertically in the air column. It seems that the upper limit of aeolian sediment transport at Mesrug is 0.8 m above the ground and saltation of particles is the dominant aeolian transport mechanism. Sediment movement occur in near gale to gale force winds and horizontal precipitation. This is mainly associated with strong north-westerly winds which are linked to a frontal system from a mid-latitudinal cyclone that has a strong meridional component or is a cut of low pressure. The data suggest that the climate change implication of a reduction in the westerly component of wind could reduce wind speeds and this could influence the magnitude and frequency of aeolian sediment transport on Marion Island in the future
- Full Text:
- Date Issued: 2019
- Authors: Nguna, Abuyiselwe Athandile
- Date: 2019
- Subjects: Eolian processes Sediments (Geology)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/17095 , vital:40848
- Description: Recent observations have recognised the increasing role of aeolian processes as a geomorphic agent on sub-Antarctic Marion Island. This study presents the first long-term data on aeolian processes and dynamics at Mesrug (46° 56’ 41”S; 37° 49’ 59”E) on subAntarctic Marion Island. An intensive and high-resolution (five-minute interval) environmental monitoring campaign was initiated using Pace Scientific XR5 data loggers while aeolian transported sediments were collected using Big Spring Number Eight (BSNE) sediment traps at four different heights above the ground. The aeolian features at Mesrug is identified as mega-ripples and is essentially an erosional feature, while annual sediment flux at 0.05 m height were calculated as 2.29 kg cm-2 y -1 . Spatial data based on a two-year survey showed that the entire surface of the study area have lowered by deflation while the ripples shifted slightly eastward (down-wind). Furthermore, the site lost 3.4 m3 of sediment between these two surveys with an average of 0.75 cm per 1 m2 across the site which has an area of 454 m2 . The study suggest that the relatively large particle size of surface sediments on Marion Island is a major contributor to the low annual aeolian sediment flux. From the AWS data it is clear that high wind speeds are frequent at Mesrug and the high wind speeds facilitating sediment movement. Sediment supply is the limiting factor of aeolian sediment transport, but even though the perennial wetness experienced on the island is not a major limiting factor to sediment flux, it may influence rate of movement. The predominant wind direction at the study site is from the south-west but maximum wind velocities are from the north-west. The data from the wind-aspirated BSNE sediment traps, indicate that sediment movement occurs closest to the surface and weight of sediment moved as well as size of particles decreases vertically in the air column. It seems that the upper limit of aeolian sediment transport at Mesrug is 0.8 m above the ground and saltation of particles is the dominant aeolian transport mechanism. Sediment movement occur in near gale to gale force winds and horizontal precipitation. This is mainly associated with strong north-westerly winds which are linked to a frontal system from a mid-latitudinal cyclone that has a strong meridional component or is a cut of low pressure. The data suggest that the climate change implication of a reduction in the westerly component of wind could reduce wind speeds and this could influence the magnitude and frequency of aeolian sediment transport on Marion Island in the future
- Full Text:
- Date Issued: 2019
Amaranth (Amaranthus cruentus) growth and nutritional contents as affected by nitrogen and potassium fertiliser and plant density
- Authors: Mamvura, Luckmore
- Date: 2019
- Subjects: Weeds -- Control -- Management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/17249 , vital:40869
- Description: The research was conducted to determine the response of amaranth growth and development to different rates of nitrogen and potassium fertilizer, the effect of plant density on herbage yield and weed management, effect of leaf age and stems on nutritional value of amaranths. The research was conducted at the University of Fort Hare Research Farm and University of Fort Hare glasshouse. For the fertilizer trial, a 4 x 3 factorial experiment: nitrogen at four levels (50kg/ha; 100kg/ha; 150kg/ha; 200kg/ha) and potassium at three levels (50kg/ha; 75kg/ha; 100kg/ha) was applied. Phosphorus was applied at 50kg/ha. The experiment was laid as randomised complete block design (RCBD) with 4 blocks (replication). The results showed that application of nitrogen and potassium treatments significantly (P < 0.05) increased plant height, stem girth and number of leaves per plant which in turn increased the crop economic leaf vegetative yield. The results also showed that at high rates of nitrogen and potassium, high vegetative yields were achieved in most cases. There was no interaction (P < 0.05) between nitrogen and potassium. Second experiment, the twelve treatments used in fertilizer trial were imposed under four different amaranth plant densities (1 200 000, 1400 000, 1600 000 and 1800 000 pph) at field level to find out growth and development performance of amaranth. In addition, at the same time investigating the effectiveness of plant density on weeds management using split plot design. The different planting densities were allocated to the main plots laid-out in RCBD. The results showed that there was no significant difference (P < 0.05) on the number of weeds under four plant densities. The results showed that different plant densities did not prevent weeds germination but the amaranths tolerate the negative effects of weeds. The nutritional analysis results showed that amaranth synthesised close to above recommended nutritional level despite different treatments applied. The third experiment: stems, lower and upper leaves were harvested separately and their nutritional composition was analysed. The results showed that the nutritional composition of stems, lower leaves and upper leaves were significantly different (P < 0.05) in most cases. Lower leaves dominated nutritional content for: crude protein crude fibre, carbohydrates, and calcium. The stems recorded least nutritional content on crude protein, crude fat, carbohydrates, calcium, potassium and sodium
- Full Text:
- Date Issued: 2019
- Authors: Mamvura, Luckmore
- Date: 2019
- Subjects: Weeds -- Control -- Management
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/17249 , vital:40869
- Description: The research was conducted to determine the response of amaranth growth and development to different rates of nitrogen and potassium fertilizer, the effect of plant density on herbage yield and weed management, effect of leaf age and stems on nutritional value of amaranths. The research was conducted at the University of Fort Hare Research Farm and University of Fort Hare glasshouse. For the fertilizer trial, a 4 x 3 factorial experiment: nitrogen at four levels (50kg/ha; 100kg/ha; 150kg/ha; 200kg/ha) and potassium at three levels (50kg/ha; 75kg/ha; 100kg/ha) was applied. Phosphorus was applied at 50kg/ha. The experiment was laid as randomised complete block design (RCBD) with 4 blocks (replication). The results showed that application of nitrogen and potassium treatments significantly (P < 0.05) increased plant height, stem girth and number of leaves per plant which in turn increased the crop economic leaf vegetative yield. The results also showed that at high rates of nitrogen and potassium, high vegetative yields were achieved in most cases. There was no interaction (P < 0.05) between nitrogen and potassium. Second experiment, the twelve treatments used in fertilizer trial were imposed under four different amaranth plant densities (1 200 000, 1400 000, 1600 000 and 1800 000 pph) at field level to find out growth and development performance of amaranth. In addition, at the same time investigating the effectiveness of plant density on weeds management using split plot design. The different planting densities were allocated to the main plots laid-out in RCBD. The results showed that there was no significant difference (P < 0.05) on the number of weeds under four plant densities. The results showed that different plant densities did not prevent weeds germination but the amaranths tolerate the negative effects of weeds. The nutritional analysis results showed that amaranth synthesised close to above recommended nutritional level despite different treatments applied. The third experiment: stems, lower and upper leaves were harvested separately and their nutritional composition was analysed. The results showed that the nutritional composition of stems, lower leaves and upper leaves were significantly different (P < 0.05) in most cases. Lower leaves dominated nutritional content for: crude protein crude fibre, carbohydrates, and calcium. The stems recorded least nutritional content on crude protein, crude fat, carbohydrates, calcium, potassium and sodium
- Full Text:
- Date Issued: 2019
An analysis of the efficiency of ontology and symbolic learning algorithms in indigenous knowledge representation
- Authors: Dzimba, Jesman
- Date: 2016
- Subjects: Ontology Computer algorithms
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11939 , vital:39120
- Description: It is without a doubt that machine learning has been the area of focus in early days of artificial intelligence, but the early neural networks approach suffered some shortcomings and this led to a temporary decline in research capacity. New symbolic learning techniques have emerged since then which have yielded promising results and have led to a revival in research in machine learning. This has seen many researchers focusing on these techniques and experimenting with them by comparing their performances for different applications. With that in mind, the research thus decided to make an analysis of the symbolic approach against other approaches such as the neural network (connectionist) to evaluate the power of the former approach. This was done by first generating an ontology that acted as a representation of some collected indigenous knowledge. It is from this ontology that a dataset was generated. The dataset was made ambiguous to see the learning power of classifiers in such data. Two experiments were done, one using WEKA and the other using Orange as tools. The reason why the two experiments were used is because there was not a single tool which contained all the required learning algorithms. The research wanted to make use of ID3 and CN2 symbolic algorithm. However, WEKA had ID3 and not CN2 while Orange had CN2 and not ID3. The most important attributes from the ontology regarding the indigenous knowledge were the name of the plant, the province it is found and the disease the plant treats. Therefore the dataset had two features which were disease and province and one label which was the name of the plant. The learning algorithm was to use the two features to generate rules used to predict the label. However, there was ambiguity on the dataset. The challenge was that two different labels would contain the same features, thus leading to wrongful classification. This was the core of the research. Even though the learning model concluded this situation as wrongful classification, in real time, a system using the same learning model would provide desired and correct results. The only flow which was there is that the learning model simply used one label to predict under and ignore the other label with similar features. This was identified as a flow for both symbolic and non-symbolic algorithms. There is no way of giving suggestions in the case a user wants a different plant but with similar features. Therefore for classification using an ambiguous dataset, both these approaches proved to have the fore mentions flow. The research then decided to use recall to analyze the power of these approaches. It was discovered that ID3 has better recall than Multilayer perceptron and Naïve Bayes algorithms when using a training set. ID3 managed to recall clearly and effectively three of its classes by a probability of 1 while Bayes Net had only one class with recall probability of 1. To further investigate the issue of recall, cross validation was used to contrast the competence of recall of the three algorithms to strengthen the assertion that indeed ID3 has a better recall as compared to the other two algorithms. Three stages of cross-validation were done, one stage using 10 fold, the other 20 fold, and the last using 50 fold. For all the different stages of crossvalidation, Bayes Net proved to perform better in terms of recall than the other two algorithms. In cross-validation, MLP could recall approximately above 88% of the instances available in contrast to when using training set where the algorithm recall only two out of 18 instances. In overall the symbolic approach proved to be a commendable approach for use over the nonsymbolic approach. The study of machine learning involves the building of learning algorithms, improving upon learning algorithms or making comparisons of machine learning algorithms. The research raised awareness on some improvements that need to be done on not only symbolic algorithms but non-symbolic ones as well. Some improvements include improving on or coming up with algorithms that suggest alternative predictions in cases of ambiguity instead of doing wrongful classification and not reflect on other possibilities.
- Full Text:
- Date Issued: 2016
- Authors: Dzimba, Jesman
- Date: 2016
- Subjects: Ontology Computer algorithms
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11939 , vital:39120
- Description: It is without a doubt that machine learning has been the area of focus in early days of artificial intelligence, but the early neural networks approach suffered some shortcomings and this led to a temporary decline in research capacity. New symbolic learning techniques have emerged since then which have yielded promising results and have led to a revival in research in machine learning. This has seen many researchers focusing on these techniques and experimenting with them by comparing their performances for different applications. With that in mind, the research thus decided to make an analysis of the symbolic approach against other approaches such as the neural network (connectionist) to evaluate the power of the former approach. This was done by first generating an ontology that acted as a representation of some collected indigenous knowledge. It is from this ontology that a dataset was generated. The dataset was made ambiguous to see the learning power of classifiers in such data. Two experiments were done, one using WEKA and the other using Orange as tools. The reason why the two experiments were used is because there was not a single tool which contained all the required learning algorithms. The research wanted to make use of ID3 and CN2 symbolic algorithm. However, WEKA had ID3 and not CN2 while Orange had CN2 and not ID3. The most important attributes from the ontology regarding the indigenous knowledge were the name of the plant, the province it is found and the disease the plant treats. Therefore the dataset had two features which were disease and province and one label which was the name of the plant. The learning algorithm was to use the two features to generate rules used to predict the label. However, there was ambiguity on the dataset. The challenge was that two different labels would contain the same features, thus leading to wrongful classification. This was the core of the research. Even though the learning model concluded this situation as wrongful classification, in real time, a system using the same learning model would provide desired and correct results. The only flow which was there is that the learning model simply used one label to predict under and ignore the other label with similar features. This was identified as a flow for both symbolic and non-symbolic algorithms. There is no way of giving suggestions in the case a user wants a different plant but with similar features. Therefore for classification using an ambiguous dataset, both these approaches proved to have the fore mentions flow. The research then decided to use recall to analyze the power of these approaches. It was discovered that ID3 has better recall than Multilayer perceptron and Naïve Bayes algorithms when using a training set. ID3 managed to recall clearly and effectively three of its classes by a probability of 1 while Bayes Net had only one class with recall probability of 1. To further investigate the issue of recall, cross validation was used to contrast the competence of recall of the three algorithms to strengthen the assertion that indeed ID3 has a better recall as compared to the other two algorithms. Three stages of cross-validation were done, one stage using 10 fold, the other 20 fold, and the last using 50 fold. For all the different stages of crossvalidation, Bayes Net proved to perform better in terms of recall than the other two algorithms. In cross-validation, MLP could recall approximately above 88% of the instances available in contrast to when using training set where the algorithm recall only two out of 18 instances. In overall the symbolic approach proved to be a commendable approach for use over the nonsymbolic approach. The study of machine learning involves the building of learning algorithms, improving upon learning algorithms or making comparisons of machine learning algorithms. The research raised awareness on some improvements that need to be done on not only symbolic algorithms but non-symbolic ones as well. Some improvements include improving on or coming up with algorithms that suggest alternative predictions in cases of ambiguity instead of doing wrongful classification and not reflect on other possibilities.
- Full Text:
- Date Issued: 2016
An analysis on the use of web-based ontology to support ubiquitous learning in South African secondary schools
- Bamigboye, Oluwatosin Omotoyosi
- Authors: Bamigboye, Oluwatosin Omotoyosi
- Date: 2018
- Subjects: Internet in education World Wide Web Ontology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12859 , vital:39385
- Description: There is certainly a need to upgrade our educational system and this can be done through technology-enhanced learning. Technology-enhanced learning can be achieved by developing a web-based ontology e-learning platform, which allows learning to take place ubiquitously. In achieving this task, this research is focusing on analyzing the use of web-based ontology to support the design and implementation of a ubiquitous learning system in South Africa. The implemented web-based ontology e-learning system was deployed and tested. The system testing was done on two variables (Information retrieval and Scalability) of localhost and client system, with the following testing metrics: time is taken for information retrieval, request time to process the request, transfer rate, time localhost receives request, time to respond, roundtrip time for request and network usage. The metrics testing was achieved using apache benchmarking console and gnuplot application to generate the data captured and performance graph, while Wireshark was also used to test/analyze round trip time and network usage through the deployed system. The results of the findings in this study show that the relationship between student and learning content becomes explicit when using ontology technology in searching, organizing, gathering and development content. Results obtained from information retrieval show that the transfer rate of information on localhost for 100 request @ current level of 5 is 37169.89kb/s, while on the client’s system, the transfer rate was 48494.36kb/s which was due to multiple request on the client’s side. Results obtained on scalability shows the round trip time which was (time to respond-time to request). The longest roundtrip was 8 seconds as a result of network being congested with multiple packets request from various sources trying to access the localhost at the same time while the fastest was 1 seconds. The implications of this results show that web-based ontology e-learning system has a positive input to teaching and learning processes in schools for content retrieval and network usage. The system furthermore shows the relationship adopted by learners and teachers, and also the match needs that arise in between. The contribution of this study adds to the existing discoveries on the use of web-based and knowledge-based ontology.
- Full Text:
- Date Issued: 2018
- Authors: Bamigboye, Oluwatosin Omotoyosi
- Date: 2018
- Subjects: Internet in education World Wide Web Ontology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12859 , vital:39385
- Description: There is certainly a need to upgrade our educational system and this can be done through technology-enhanced learning. Technology-enhanced learning can be achieved by developing a web-based ontology e-learning platform, which allows learning to take place ubiquitously. In achieving this task, this research is focusing on analyzing the use of web-based ontology to support the design and implementation of a ubiquitous learning system in South Africa. The implemented web-based ontology e-learning system was deployed and tested. The system testing was done on two variables (Information retrieval and Scalability) of localhost and client system, with the following testing metrics: time is taken for information retrieval, request time to process the request, transfer rate, time localhost receives request, time to respond, roundtrip time for request and network usage. The metrics testing was achieved using apache benchmarking console and gnuplot application to generate the data captured and performance graph, while Wireshark was also used to test/analyze round trip time and network usage through the deployed system. The results of the findings in this study show that the relationship between student and learning content becomes explicit when using ontology technology in searching, organizing, gathering and development content. Results obtained from information retrieval show that the transfer rate of information on localhost for 100 request @ current level of 5 is 37169.89kb/s, while on the client’s system, the transfer rate was 48494.36kb/s which was due to multiple request on the client’s side. Results obtained on scalability shows the round trip time which was (time to respond-time to request). The longest roundtrip was 8 seconds as a result of network being congested with multiple packets request from various sources trying to access the localhost at the same time while the fastest was 1 seconds. The implications of this results show that web-based ontology e-learning system has a positive input to teaching and learning processes in schools for content retrieval and network usage. The system furthermore shows the relationship adopted by learners and teachers, and also the match needs that arise in between. The contribution of this study adds to the existing discoveries on the use of web-based and knowledge-based ontology.
- Full Text:
- Date Issued: 2018
An assessment of quality, class and grade of service (QoS, CoS and GoS) over worldwide interoperability for microwave access (WiMax) networks through performance evaluation of bandwidth
- Authors: Nomnga, Phumzile
- Date: 2016
- Subjects: Wireless communication systems Wireless LANs -- Standards Broadband communication systems
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8033 , vital:31481
- Description: The Dwesa WiMAX network provides broadband communications over wireless connectivity for various types of multimedia traffic, such as emailing, browsing, VoIP, file transfer, etc. to the community members. The community members of Dwesa use schools’ computer labs to access the network and generate the aforementioned multimedia packets on dedicated timeslots and thus cause network congestion during such timeslots. Against this background, WiMAX implementation has faced several challenges in living up to its objectives in RMAs. Quality of Service (QoS) degradation as a result of high traffic demands remains one of the challenges thwarting WiMAX implementation. The GoS is also bound to get compromised as connectivity demands arise consistently with more subscribers connecting to the network, making it difficult to measure the success a subscriber is expected to have in accessing the network. The CoS and SchedType play a significant role in the redistribution of the available bandwidth to all bandwidth requests. This research project exploits this avenue to assess the resultant degradation of QoS and GoS caused by the inconsistent availability of bandwidth as redistributed by the CoS combination with a SchedType. The four CoS which are, namely, the UGS, rtPS, nrtPS and BE were implemented with the different SchedTypes, namely, MBQOS, FCFS and rtPS. Although the implementation process was conducted in a simulated environment using NS-3, the simulated network emulated the network setup implemented in Dwesa. The outcomes of the implementation suggests that certain combinations of the CoS’s with SchedTypes can lead to degradation of QoS whilst some combinations can redistribute the available bandwidth to ensure the provisioning of guaranteed QoS.
- Full Text:
- Date Issued: 2016
- Authors: Nomnga, Phumzile
- Date: 2016
- Subjects: Wireless communication systems Wireless LANs -- Standards Broadband communication systems
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8033 , vital:31481
- Description: The Dwesa WiMAX network provides broadband communications over wireless connectivity for various types of multimedia traffic, such as emailing, browsing, VoIP, file transfer, etc. to the community members. The community members of Dwesa use schools’ computer labs to access the network and generate the aforementioned multimedia packets on dedicated timeslots and thus cause network congestion during such timeslots. Against this background, WiMAX implementation has faced several challenges in living up to its objectives in RMAs. Quality of Service (QoS) degradation as a result of high traffic demands remains one of the challenges thwarting WiMAX implementation. The GoS is also bound to get compromised as connectivity demands arise consistently with more subscribers connecting to the network, making it difficult to measure the success a subscriber is expected to have in accessing the network. The CoS and SchedType play a significant role in the redistribution of the available bandwidth to all bandwidth requests. This research project exploits this avenue to assess the resultant degradation of QoS and GoS caused by the inconsistent availability of bandwidth as redistributed by the CoS combination with a SchedType. The four CoS which are, namely, the UGS, rtPS, nrtPS and BE were implemented with the different SchedTypes, namely, MBQOS, FCFS and rtPS. Although the implementation process was conducted in a simulated environment using NS-3, the simulated network emulated the network setup implemented in Dwesa. The outcomes of the implementation suggests that certain combinations of the CoS’s with SchedTypes can lead to degradation of QoS whilst some combinations can redistribute the available bandwidth to ensure the provisioning of guaranteed QoS.
- Full Text:
- Date Issued: 2016
An Assessment of the Environmental Impacts of Urban Sprawl in Buffalo City Metropolitan Municipality, Eastern Cape Province
- Authors: Matiza, Collins
- Date: 2019
- Subjects: Cities and towns -- Growth -- Environmental aspects City planning
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/17260 , vital:40870
- Description: Large industrial and residential developments near towns and along highways associated with public policies have transformed the pattern of development over the recent years, creating a new urbanisation phenomenon; urban sprawl. Indiscriminate population densities, discontinuous and fragmented settlements, largely define urban sprawl. The progression of urban sprawl can be described by transformation in pattern over time, like proportional increase in built-up surface to population leading to rapid urban spatial expansion. Stemming an understanding from the processes, causes and patterns of urban sprawl, the consequences of sprawl on land and vegetation can be analysed. Environmental impacts to both the rural and urban population emanate from such instances, creating an excessive liability to the government. With attention to this and recognising the lack of discussion on the matter, the research deliberates some of the impacts observed in Buffalo City Metropolitan Municipality, Eastern Cape, South Africa. The study makes use of Geographic Information Systems and Remote Sensing with the assistance of landscape metrics. The influence of urban sprawl in this municipality has revealed impacts on vegetation, green areas and land in general. The results disclose that urban sprawl is a multidimensional phenomenon that is better explained using various methods (indices). Buffalo City Metropolitan municipality is located in Eastern Cape amidst the thicket ecosystem, the municipality has grown and expanded over the recent past. The study spread over an 18-year period from 1994- 2012. Based on field surveys and SPOT imagery, built-up areas of BCMM was extracted for different periods. Data used for the study are census data for BCMM, 1994, 2000, 2006 and 2012 SPOT images, images of BCMM acquired from Google earth 2018. The rate of transformation of the area was calculated and it was higher compared to that of population growth. Based on this data urban growth are analysed with the assistance of landscape metrics that include Shannon entropy. The outcomes confirm that this metropolitan municipality has experienced sprawl and sprawl has done so at cumulative rate.
- Full Text:
- Date Issued: 2019
- Authors: Matiza, Collins
- Date: 2019
- Subjects: Cities and towns -- Growth -- Environmental aspects City planning
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/17260 , vital:40870
- Description: Large industrial and residential developments near towns and along highways associated with public policies have transformed the pattern of development over the recent years, creating a new urbanisation phenomenon; urban sprawl. Indiscriminate population densities, discontinuous and fragmented settlements, largely define urban sprawl. The progression of urban sprawl can be described by transformation in pattern over time, like proportional increase in built-up surface to population leading to rapid urban spatial expansion. Stemming an understanding from the processes, causes and patterns of urban sprawl, the consequences of sprawl on land and vegetation can be analysed. Environmental impacts to both the rural and urban population emanate from such instances, creating an excessive liability to the government. With attention to this and recognising the lack of discussion on the matter, the research deliberates some of the impacts observed in Buffalo City Metropolitan Municipality, Eastern Cape, South Africa. The study makes use of Geographic Information Systems and Remote Sensing with the assistance of landscape metrics. The influence of urban sprawl in this municipality has revealed impacts on vegetation, green areas and land in general. The results disclose that urban sprawl is a multidimensional phenomenon that is better explained using various methods (indices). Buffalo City Metropolitan municipality is located in Eastern Cape amidst the thicket ecosystem, the municipality has grown and expanded over the recent past. The study spread over an 18-year period from 1994- 2012. Based on field surveys and SPOT imagery, built-up areas of BCMM was extracted for different periods. Data used for the study are census data for BCMM, 1994, 2000, 2006 and 2012 SPOT images, images of BCMM acquired from Google earth 2018. The rate of transformation of the area was calculated and it was higher compared to that of population growth. Based on this data urban growth are analysed with the assistance of landscape metrics that include Shannon entropy. The outcomes confirm that this metropolitan municipality has experienced sprawl and sprawl has done so at cumulative rate.
- Full Text:
- Date Issued: 2019
An evaluation and estimation of risk factors associated with cholera : case study of registered patients in Raymond Mhlaba local municipality, South Africa
- Authors: Osuji, Georgeleen O
- Date: 2017
- Subjects: Cholera -- South Africa -- Eastern Cape Risk assessment -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15562 , vital:40459
- Description: Background: Cholera is an acute infectious disease of the small intestine caused by the bacterium called Vibrio cholerae, which has two serogroups01and 0139which is also known as choleragenic V. cholerae. This disease is characterized by profuse watery diarrhoea and severe dehydration which can lead to death of both adult and children if treatment is not promptly given. Cholera is spread through ingestion of V. cholera contaminated water and food. Cholera has displayed global presence more than seven times and caused tremendous disaster to humankind. Method: This was a retrospective study among patients with cholera within the period of ten years (2005 to 2015) and the total number of patients was 106. The target population for this study were patients at Raymond Mhlaba Local Municipality who attended Victoria hospital and were diagnosed with Vibrio cholerae species with respect to sources of water and non-water sources during the mentioned period. A multivariate Logistic regression was used to determine the risk factors of cholera and comparison was made in the treatment of cholera outcomes for factors which were statistically significant at P < 0.05. Results: The median age was 24.5 (IQR: 7.0-44.8) for all respondents with cholera. Patients within the age range of 26-40 and 41-55 were found to have a higher risk of cholera (2.20, 95percent CI: 1.51, 4.22) and (1.13, 95percent CI: 0.61, 2.01) respectively. The risk of cholera was considerably higher among the black race (2.51, 95percent CI: 1.52, 4.31) compared to the coloured (1.33, 95percent CI: 0.75, 3.713). Patients who used source of water supply from carrier/Tanker and Dam/River had higher increased risk of contracting cholera (1.71, 95percent CI: 0.92, 3.62) and (2.61, 95percent CI: 1.38, 4.25) respectively compared to patients that used other sources of water. Home, party and restaurant as places patients had eaten 24 hours earlier before the onset of cholera were associated with increased risk of severe cholera. Patients who shared toilet facilities had increased risk of cholera (0.91, 95percent CI: 0.47, 1.62) compared to the ones who used private toilet. Those patients who did not practice hand washing had an increased risk of contracting cholera (1.45, 95percent CI: 0.88, 2.12) compared to the ones who washed their hands. When Logistic regression was carried out, the following risk factors were found to be statistically significant in causing cholera at 5percent significance level; Age ( 26-40), gender, level of education, marital status, sources of water supply, place eaten in the last 24 hours before onset of cholera, type of toilet used and hand washing. Conclusion: Improvement in level of education, sources of water supply, place of last eaten before cholera sickness, toilet facilities, hand washing practices are key risk factors for cholera disease and hospitalization among patients in Raymond Mhlaba local Municipality, Eastern Cape. The strong association between water and sanitation highlights the need for a more thorough assessment of potential waterborne exposures and the risk faced by family members suffering from cholera infection cases and may warrant renewed research regarding the use of targeted chemoprophylaxis in endemic rural settings.
- Full Text:
- Date Issued: 2017
- Authors: Osuji, Georgeleen O
- Date: 2017
- Subjects: Cholera -- South Africa -- Eastern Cape Risk assessment -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15562 , vital:40459
- Description: Background: Cholera is an acute infectious disease of the small intestine caused by the bacterium called Vibrio cholerae, which has two serogroups01and 0139which is also known as choleragenic V. cholerae. This disease is characterized by profuse watery diarrhoea and severe dehydration which can lead to death of both adult and children if treatment is not promptly given. Cholera is spread through ingestion of V. cholera contaminated water and food. Cholera has displayed global presence more than seven times and caused tremendous disaster to humankind. Method: This was a retrospective study among patients with cholera within the period of ten years (2005 to 2015) and the total number of patients was 106. The target population for this study were patients at Raymond Mhlaba Local Municipality who attended Victoria hospital and were diagnosed with Vibrio cholerae species with respect to sources of water and non-water sources during the mentioned period. A multivariate Logistic regression was used to determine the risk factors of cholera and comparison was made in the treatment of cholera outcomes for factors which were statistically significant at P < 0.05. Results: The median age was 24.5 (IQR: 7.0-44.8) for all respondents with cholera. Patients within the age range of 26-40 and 41-55 were found to have a higher risk of cholera (2.20, 95percent CI: 1.51, 4.22) and (1.13, 95percent CI: 0.61, 2.01) respectively. The risk of cholera was considerably higher among the black race (2.51, 95percent CI: 1.52, 4.31) compared to the coloured (1.33, 95percent CI: 0.75, 3.713). Patients who used source of water supply from carrier/Tanker and Dam/River had higher increased risk of contracting cholera (1.71, 95percent CI: 0.92, 3.62) and (2.61, 95percent CI: 1.38, 4.25) respectively compared to patients that used other sources of water. Home, party and restaurant as places patients had eaten 24 hours earlier before the onset of cholera were associated with increased risk of severe cholera. Patients who shared toilet facilities had increased risk of cholera (0.91, 95percent CI: 0.47, 1.62) compared to the ones who used private toilet. Those patients who did not practice hand washing had an increased risk of contracting cholera (1.45, 95percent CI: 0.88, 2.12) compared to the ones who washed their hands. When Logistic regression was carried out, the following risk factors were found to be statistically significant in causing cholera at 5percent significance level; Age ( 26-40), gender, level of education, marital status, sources of water supply, place eaten in the last 24 hours before onset of cholera, type of toilet used and hand washing. Conclusion: Improvement in level of education, sources of water supply, place of last eaten before cholera sickness, toilet facilities, hand washing practices are key risk factors for cholera disease and hospitalization among patients in Raymond Mhlaba local Municipality, Eastern Cape. The strong association between water and sanitation highlights the need for a more thorough assessment of potential waterborne exposures and the risk faced by family members suffering from cholera infection cases and may warrant renewed research regarding the use of targeted chemoprophylaxis in endemic rural settings.
- Full Text:
- Date Issued: 2017
An evaluation of medicinal plants used in South Africa and Lesotho for uterotonic contractile purposes
- Authors: Smit, Inge
- Date: 2016
- Subjects: Traditional medicine -- South Africa Traditional medicine -- Lesotho
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15232 , vital:40256
- Description: Background One of the leading cause of maternal mortality globally is postpartum haemorrhage (PPH), which mainly occur in developing countries. By identifying traditional medicinal plants that is used by Traditional birth attendants we can analysis the plants for cyclotides which contain uterotonic properties and a wide variety of other properties. The indigenous knowledge of traditional medicinal plants need to be preserved and scientifically proven to ensure future drug development and continued use of these plants. Cyclotides can be used as a backbone to develop novel drugs in that cyclotides are very stable proteins. Methods: Ten plants were identified that are commonly used to prevent or treat postpartum haemorrhage. The plant samples were collected, prepared and dried in South Africa. The plants were analysed in Austria. The plants underwent extraction of one gram of each plant was analysed using: Matrix-Assisted Laser desorption Ionization time-of-flight Mass Spectrometry (MALDI-TOF-MS); Tandem Mass Spectrometry and Analysis by High-performance Liquid Chromatography (HPLC). Results None of the ten plants analysed showed the presence of cyclotides. It is important to report negative results, because it informs the academic fraternity and could be entered in a global data base of results. The plants analysed is known to be used by Traditional Birth Attendants for the treatment or prevention of postpartum haemorrhage. Conclusion All the plants analysed are commonly used to prevent and treat PPH. The fact that no cyclotides were found do not dispute the practical use of these plants to prevent and treat PPH. There continue to be a gap in what uterotonic properties these plants contain and should be further investigated.
- Full Text:
- Date Issued: 2016
- Authors: Smit, Inge
- Date: 2016
- Subjects: Traditional medicine -- South Africa Traditional medicine -- Lesotho
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15232 , vital:40256
- Description: Background One of the leading cause of maternal mortality globally is postpartum haemorrhage (PPH), which mainly occur in developing countries. By identifying traditional medicinal plants that is used by Traditional birth attendants we can analysis the plants for cyclotides which contain uterotonic properties and a wide variety of other properties. The indigenous knowledge of traditional medicinal plants need to be preserved and scientifically proven to ensure future drug development and continued use of these plants. Cyclotides can be used as a backbone to develop novel drugs in that cyclotides are very stable proteins. Methods: Ten plants were identified that are commonly used to prevent or treat postpartum haemorrhage. The plant samples were collected, prepared and dried in South Africa. The plants were analysed in Austria. The plants underwent extraction of one gram of each plant was analysed using: Matrix-Assisted Laser desorption Ionization time-of-flight Mass Spectrometry (MALDI-TOF-MS); Tandem Mass Spectrometry and Analysis by High-performance Liquid Chromatography (HPLC). Results None of the ten plants analysed showed the presence of cyclotides. It is important to report negative results, because it informs the academic fraternity and could be entered in a global data base of results. The plants analysed is known to be used by Traditional Birth Attendants for the treatment or prevention of postpartum haemorrhage. Conclusion All the plants analysed are commonly used to prevent and treat PPH. The fact that no cyclotides were found do not dispute the practical use of these plants to prevent and treat PPH. There continue to be a gap in what uterotonic properties these plants contain and should be further investigated.
- Full Text:
- Date Issued: 2016
An evaluation of the impact of the biogas digesters project at Melani village, Eastern Cape, South Africa
- Authors: Mthimunye , Thabiso Vincent
- Date: 2018
- Subjects: Biogas
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14561 , vital:40014
- Description: A study was conducted in Melani rural community of Raymond Mhlaba district in Eastern Cape, with the aim of identifying types of energy sources and households energy utilization. Melani village (32°43’29” S, 27°07’35” E) is 13 km away from Alice, the closest town and its household population is about 350. The survey was conducted with 50% of the randomly chosen households using semi-structured questionnaires and some onset CTA-A hobo current transducers were installed in three households to measure electricity used for either cooking, heating or lighting. The survey shows that electricity (supplied by Eskom) is the main source of energy for cooking, lighting and heating, while paraffin and candles are also used for lighting. The data collected using the data acquisition system has also shown that each household consumes an average of 140 kWh of electricity per month. Assuming this amount of energy being used throughout the year, on average the households consume 1680 kWh of electricity per year. The research concludes that there is a need to promote sustainable energy resources and technologies such as the use of biogas digesters as an alternative source of energy since the households has on average 20 of cattle, 10 of goats, 10 sheep and 4 donkeys. The research has also shown that the economic analysis of the biogas project is financially feasible. The Net present value was high and positive showing the feasibility of the investment on the project. The payback period was implying that the project pays itself off within the service life or within a set payback limit, which must be shorter than the technical service period of 5 years. The research has further shown that the emission factor for carbon dioxide for every 1MWh of electrical energy saved is 1.07 kg and consequently a corresponding volume of avoidance water is 1.40 KL. This can be mentioned that this monthly cost saving in the electrical energy consumption can go a long way in improving the social and economic welfare of the people. More so, it also vi plays a key role in the reduction of the global warming potential and the amount of air pollutant in the atmosphere. The avoidance water also contributed greatly in reducing the total volume of water used in the cooling towers of the coal power generation plant.
- Full Text:
- Date Issued: 2018
- Authors: Mthimunye , Thabiso Vincent
- Date: 2018
- Subjects: Biogas
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14561 , vital:40014
- Description: A study was conducted in Melani rural community of Raymond Mhlaba district in Eastern Cape, with the aim of identifying types of energy sources and households energy utilization. Melani village (32°43’29” S, 27°07’35” E) is 13 km away from Alice, the closest town and its household population is about 350. The survey was conducted with 50% of the randomly chosen households using semi-structured questionnaires and some onset CTA-A hobo current transducers were installed in three households to measure electricity used for either cooking, heating or lighting. The survey shows that electricity (supplied by Eskom) is the main source of energy for cooking, lighting and heating, while paraffin and candles are also used for lighting. The data collected using the data acquisition system has also shown that each household consumes an average of 140 kWh of electricity per month. Assuming this amount of energy being used throughout the year, on average the households consume 1680 kWh of electricity per year. The research concludes that there is a need to promote sustainable energy resources and technologies such as the use of biogas digesters as an alternative source of energy since the households has on average 20 of cattle, 10 of goats, 10 sheep and 4 donkeys. The research has also shown that the economic analysis of the biogas project is financially feasible. The Net present value was high and positive showing the feasibility of the investment on the project. The payback period was implying that the project pays itself off within the service life or within a set payback limit, which must be shorter than the technical service period of 5 years. The research has further shown that the emission factor for carbon dioxide for every 1MWh of electrical energy saved is 1.07 kg and consequently a corresponding volume of avoidance water is 1.40 KL. This can be mentioned that this monthly cost saving in the electrical energy consumption can go a long way in improving the social and economic welfare of the people. More so, it also vi plays a key role in the reduction of the global warming potential and the amount of air pollutant in the atmosphere. The avoidance water also contributed greatly in reducing the total volume of water used in the cooling towers of the coal power generation plant.
- Full Text:
- Date Issued: 2018
An in silico analysis, purification and partial kinetic characterisation of a serine protease from Gelidium pristoides
- Authors: Ntsata, Zolani
- Date: 2020
- Subjects: Gelidium Proteolytic enzymes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12076 , vital:39149
- Description: The aim of this study was to characterize the protease enzyme (s) from red algae. An in silico analysis of red algae genomes was used to identify gene coding for protease. Protease sequences identified from these genomes were examined for conserved domains, active site and structures. The domain search revealed that the identified sequences were from the five classes of protease enzymes. For function inference, the red algae sequences were aligned to identify the catalytic sites, and the tertiary structures were predicted using homology modelling. An in silico analysis provides an indication of the class and potential functions of the enzymes. However, it cannot predict whether the gene is constitutively expressed in the red algae or under which conditions it may be induced, and it cannot determine the kinetic efficiency of an enzyme against various substrate, or the optimum conditions for the protein activity. Attempts to clone and recombinantly express selected red algae proteases, proved unsuccessful, as the available genomes where from red algae species found mainly in Asia, and the designed primers, therefore, did not amplify a corresponding PCR product from the red algae harvested in South Africa. Crude extracts of red algae collected from Kenton-on-Sea, along the East Coast of South Africa, were screened for protease activity using Benzoyl-Arginine-pNitroAnilide (BApNA) as substrate. The proteases detected in the crude extract were purified using ammonium sulphate precipitation and HiPrep DEAE FF 16/10; CM FF 16/10, and HiPrep Q FF 16/10 columns for ion-exchange chromatography. The HiPrep Q FF 16/10 column yielded active protein, which revealed two bands of 11kDa and 17kDa on SDS-PAGE. It was assumed that these bands represented two subunits of the purified protease. Kinetic characterisation of the purified protease revealed a pH optimum of 9, using BApNA as substrate, a temperature optimum at 60ºC, and sensitivity to temperature when stored above 4ºC. The protease activity was inhibited by Ferric chloride (32%), induced by calcium chloride (156%), no inhibition by magnesium chloride (97%) and slight inhibition by potassium chloride (77%) and manganese chloride (70%). Phenylmethylsulfonyl fluoride (PMSF), a serine protease inhibitor, almost totally inhibited the protease activity, indicating that the protease from red algae was most likely a serine protease. The Km and kcat values were 1.96 µM, and 0.364 s -1 , respectively using BApNA as the substrate. This study revealed that the red algae genome contains numerous genes that encode for proteases from almost all the classes of proteases. A serine protease from the red algae Gelidium pristoides was partially purified and kinetically characterised, confirming that red algae found along the Eastern Coast of South Africa contain genes that express active proteases that may be of medical or industrial interest. Further studies, however, are required to recombinantly express, purify and characterise the numerous proteases encoded by the genes identified in the in silico analysis of this study.
- Full Text:
- Date Issued: 2020
- Authors: Ntsata, Zolani
- Date: 2020
- Subjects: Gelidium Proteolytic enzymes
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/12076 , vital:39149
- Description: The aim of this study was to characterize the protease enzyme (s) from red algae. An in silico analysis of red algae genomes was used to identify gene coding for protease. Protease sequences identified from these genomes were examined for conserved domains, active site and structures. The domain search revealed that the identified sequences were from the five classes of protease enzymes. For function inference, the red algae sequences were aligned to identify the catalytic sites, and the tertiary structures were predicted using homology modelling. An in silico analysis provides an indication of the class and potential functions of the enzymes. However, it cannot predict whether the gene is constitutively expressed in the red algae or under which conditions it may be induced, and it cannot determine the kinetic efficiency of an enzyme against various substrate, or the optimum conditions for the protein activity. Attempts to clone and recombinantly express selected red algae proteases, proved unsuccessful, as the available genomes where from red algae species found mainly in Asia, and the designed primers, therefore, did not amplify a corresponding PCR product from the red algae harvested in South Africa. Crude extracts of red algae collected from Kenton-on-Sea, along the East Coast of South Africa, were screened for protease activity using Benzoyl-Arginine-pNitroAnilide (BApNA) as substrate. The proteases detected in the crude extract were purified using ammonium sulphate precipitation and HiPrep DEAE FF 16/10; CM FF 16/10, and HiPrep Q FF 16/10 columns for ion-exchange chromatography. The HiPrep Q FF 16/10 column yielded active protein, which revealed two bands of 11kDa and 17kDa on SDS-PAGE. It was assumed that these bands represented two subunits of the purified protease. Kinetic characterisation of the purified protease revealed a pH optimum of 9, using BApNA as substrate, a temperature optimum at 60ºC, and sensitivity to temperature when stored above 4ºC. The protease activity was inhibited by Ferric chloride (32%), induced by calcium chloride (156%), no inhibition by magnesium chloride (97%) and slight inhibition by potassium chloride (77%) and manganese chloride (70%). Phenylmethylsulfonyl fluoride (PMSF), a serine protease inhibitor, almost totally inhibited the protease activity, indicating that the protease from red algae was most likely a serine protease. The Km and kcat values were 1.96 µM, and 0.364 s -1 , respectively using BApNA as the substrate. This study revealed that the red algae genome contains numerous genes that encode for proteases from almost all the classes of proteases. A serine protease from the red algae Gelidium pristoides was partially purified and kinetically characterised, confirming that red algae found along the Eastern Coast of South Africa contain genes that express active proteases that may be of medical or industrial interest. Further studies, however, are required to recombinantly express, purify and characterise the numerous proteases encoded by the genes identified in the in silico analysis of this study.
- Full Text:
- Date Issued: 2020