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.
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An analysis on the use of web-based ontology to support ubiquitous learning in South African secondary schools
- 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.
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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.
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Assessing the implementation and effects of the Fetsa Tlala Food Initiative Programme in achieving its vision of eradicating household level food insecurity in Lukhanji Local Municipality, Eastern Cape Province, South Africa
- Authors: Njara, L I
- Date: 2018
- Subjects: Poverty -- South Africa -- Eastern Cape Food security -- South Africa -- Eastern Cape Households -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10476 , vital:35484
- Description: Declining agrarian activities in significant parts of the country, even in the subsistence sector, has meant that access to food is increasingly a function of household cash income, hence low-income households experience inadequate access to food. Over 12 million people in South Africa are vulnerable to food insecurity. Since 2013, substantial efforts and large sums of money have been devoted to poverty reduction through government’s Fetsa Tlala Food Production Initiative. Fetsa Tlala was conceptualised as an integrated government framework that seeks to promote food and nutrition security and to address the structural causes of food insecurity, which continue to perpetuate inequality and social exclusion. The main objective of this study is to assess the implementation and effects of Fetsa Tlala. The specific objectives include: to measure the direct and indirect benefits of Fetsa Tlala; to assess the cost-effectiveness of the programme; to evaluate the model of the programme using a social systems approach; and to assess the implementation approach of Fetsa Tlala. A cross-sectional study was carried on a sample of 70 households and four Fetsa Tlala projects in the Eastern Cape. Households were selected using the simple random sampling procedure. Structured and semi-structured interviews using questionnaires were conducted. The research objectives were analysed using both qualitative and quantitative approaches. Among the quantitative approaches used was a micro simulation exercise, which was performed to help understand the cost-effectiveness of the programme. The results show that the business model of the programme is not built with sustainability in mind and the systems approach was ignored when designing the programme. Furthermore, the cost of the programme outweighs its benefits. This study recommends that the programme should take into account human development and build a needs-based approach going forward. Further recommendations are that the government should target relevant partners, and prioritise agricultural insurance, infrastructure and agro-processing.
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Assessing the income derived from agricultural hawking in Buffalo City Metropolitan Municipality, Eastern Cape, South Africa
- Authors: Seteni, Vuyo
- Date: 2018
- Subjects: Street vendors -- South Africa -- Eastern Cape Street vendors -- South Africa -- Eastern Cape -- Economic conditions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10167 , vital:35364
- Description: The hawking business has grown profusely in Buffalo City Metropolitan Municipality, to such an extent that street hawkers are found on every street corner of the Metro. The literature suggests that street hawking holds great potential for employment creation for the unskilled population who cannot find employment opportunities in the formal sector. In light of the proliferation of street hawking in BCMM, the study aimed at assessing the performance of agricultural hawkers in the municipality by means of looking at hawkers’ strategies, determining their sales and net income, and ascertaining their level of ‘job satisfaction’. The sample was selected from the population of hawkers in three major towns of BCMM, namely Mdantsane, East London and King William’s Town. A sum of 200 respondents were selected in the study through interval based probability sampling. The study made use of a cross tabulation of the hawkers’ income according to the three main towns. The results revealed that that agricultural hawking contributes to poverty alleviation in Buffalo City Metropolitan Municipality, as the majority of hawkers earn enough to live above the poverty line. A correlation matrix was used to ascertain the strength and direction of association between hawkers’ monthly income and selected independent variables. The study also used an ordered probit model to determine which specific variables affect hawkers’ monthly income generated from fruit and vegetable sales. The results from the model suggest that business training is significantly and positively related to increasing monthly income, as are age, years of experience, and membership of a hawkers’ association. The study recommends that Buffalo City Metropolitan Municipality build new markets and improve the infrastructure of existing markets, and also provide proper sanitation and clean water to avoid unhygienic situations in street hawkers’ markets.
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Calibration and validation of satellite data (images) over inland water bodies and the effect caused by the adjacency towards them
- Authors: Faniso, Zimbini
- Date: 2018
- Subjects: Hydrology Remote sensing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10350 , vital:35400
- Description: Remote sensing of inland water quality is a particularly challenging satellite Earth observation (EO) application. This arises because inland water bodies are small and optically complex targets that are generally dark compared to surrounding land. Inland water bodies are source supplies of water for both living and non-living organisms, that include human beings hence they need an observation. The spatial distribution of water changes over time and that leads to issues in different sectors like agricultural sector, environmental services and ecological issues. Signal reaching the satellite is usually dominated by light scattered in the atmosphere. Aerosols are strongly variable atmospheric constituents and play a major role in generating this unwanted signal which must be quantified and removed before any conclusions about water state and condition. In order to see how the aerosols affected the water state the light scattered in the atmosphere will be observed through electromagnetic spectrum bands in the atmosphere. This study will analyse the visible and near infrared wavebands of the electromagnetic spectrum as well as where it will be easy to distinguish the atmospheric noise types. A field campaign has been executed at Roodeplaat dam near Pretoria relating to Calibration and Validation (CalVal) of the recently launched Sentinel 2 and Sentinel 3 satellites. In situ measurements were taken at Roodeplaat dam simultaneously with the satellite overpass. Atmospheric Radiative Transfer Modelling (RTM) is required to analyse the satellite surface measurement data that is in the form of radiant quantities. Aerosol models for radiative transfer have been evaluated and refined to improve retrieval accuracy of water-leaving radiance at Roodeplaat dam. A retrieval algorithm for water-leaving radiance (Lw) and remote-sensing reflectance has been developed to analyse the sensitivity of the retrieval to aerosol optical properties, sensitivities, as well as proposals for enhanced retrieval methods, are presented.
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Classification of Distinct Fuzzy Subgroups of the Dihedral Group Dp nq for p and q distinct primes and n ∈ N
- Authors: Nxala, Baphumelele Ellen
- Date: 2018
- Subjects: Fuzzy mathematics Fuzzy sets
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14516 , vital:39997
- Description: In this dissertation, we classify distinct fuzzy subgroups of the dihedral group Dpnq, for p and q distinct primes and n ∈ N, under a natural equivalence relation of fuzzy subgroups and a fuzzy isomorphism. We aim to present formulae for the number of maximal chains and the number of distinct fuzzy subgroups of this group. Our study will include some theory on non-abelian groups since the classification of distinct fuzzy subgroups of this group relies on the crisp characterization of maximal chains. We give the definition of a natural equivalence relation introduced by Murali and Makamba in [67] which we will use in this study. Based on this definition, we introduce two counting techniques that we will use to compute the number of distinct fuzzy subgroups of Dpnq. In this dissertation, we use the criss-cut counting technique as our primary method of enumeration, and the cross-cut method serves as a means of verifying results we obtain from our primary method. To classify distinct fuzzy subgroups of this group, we begin by investigating the dihedral groups Dpnq, for p and q distinct primes and specific values of n = 2 and 3 to observe a trend. We classify the flags of these groups using the characterization of flags introduced in [93]. From this characterization, we then present formulae for the number of distinct fuzzy subgroups attributed to the flags of Dp 2q and Dp 3q . To generalise results for Dpnq, for p and q distinct primes and n ∈ N, we characterize the flags of this group and classify them as either cyclic, mdcyclic for 1 ≤ m ≤ n, or b-cyclic. Finally, we establish a general formula for the number of distinct fuzzy subgroups obtainable from these flags. We conclude by comparing results obtained from using our general formula to those obtained by other researchers for the same group. Based on the results from this study, we give an outline of future research work
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Design and development of a context sensitive rural development software application for eService provisioning
- Authors: Masikisiki, Lizo
- Date: 2018
- Subjects: Rural development Electronic commerce Computer networks
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15332 , vital:40366
- Description: After more than a decade since South Africa realized the importance of Information and Communication Technology (ICT) and the role it can play to deliver services, the country is still confronted by a number of challenges challenges that hinder the implementation of a fully-fledged ICT-based system in a form of electronic government to better deliver services and information. While rural development remains as one of the country’s greatest concerns, ICT is among approaches and perspectives that are recognized for not only accelerating rural development but also for providing the country’s economic growth. This research was set to investigate approaches to implement ICT solutions for rural development and service provisioning in the context of electronic government. The research focused more on the technical skills to implement such ICT systems for the benefit of rural development and e-government stakeholders that have an interest in design and development of an integrated and interoperable solution to accelerate service delivery, especially in rural communities. A mixed methods approach was used throughout the research accompanied by an evolutionary prototyping to development the desired prototype. A study was then conducted to gain an understanding of the state and the needs of rural communities to date. The results of the study yielded a number of urbanized service providers that rural dwellers need to timeously visit to consume services. Scenarios to design and develop the intended prototypes were then drawn from these results. The overall implementation of the prototypes produced an integrated platform that allows multiple disparate systems to communicate, share and use information. The qualities of the prototype are what this research recommends to relevant to stakeholders in order to implement an integrated and interoperable e-government system that elevates rural development programs and service delivery.
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Dynamic Mathematical Modeling in Chemical Reaction Networks
- Authors: Gurajena, Simba
- Date: 2018
- Subjects: Chemical reaction
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11961 , vital:39122
- Description: Many students are familiar with the idea of ecological, financial modeling and modeling in other fields, but modeling in engineering fields is still an area to be looked at. In this discussion the researcher will deal with chemical reaction networks. This will cover areas in chemical reaction, interaction diagrams and the associated models. The discussion will also cover dynamic behaviour of reaction networks. The law of mass action and examples of simple networks will be dealt with. Differential equation models of biochemical and genetic systems are invariantly nonlinear, and as such numerical simulation is used to solve such models. The use of numerical simulation packages will be discussed and separation of timescale and model reduction will form part of the discussion.
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Effects of production systems and canola meal supplementation on carcass and meat quality characteristics of spent laying hens
- Authors: Semwogerere, Farouk
- Date: 2018
- Subjects: Broilers (Chickens) -- Feeding and feeds Chickens -- Feeding and feeds Chicken industry -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9242 , vital:34309
- Description: This study evaluated the carcass and meat quality traits of spent laying hens as influenced by production systems (conventional cages and free range) and the inclusion/exclusion of canola meal in their diets. A total of 30 free range and 60 battery cage reared Lohmann Brown-Elite spent laying hens were obtained from a commercial egg producer. The 30 free range hens (53 weeks of age) and 30 of the caged hens (40 weeks of age) were fed a conventional diet, while the remaining 30 caged hens (48 weeks of age) were fed a diet supplemented with canola meal (20 percent). Carcass, portion and organ weights were determined. Physical attributes and proximate composition were analyzed for, with additional fatty acids and sensory profiles being determined for the effects of canola meal inclusion in the diet. Caged hens had heavier (P ≤ 0.05) warm and cold carcasses, thigh, wing and feet compared to free range hens. The percentages of the breast (26.1 ± 0.51 vs. 28.3 ± 0.28), drum, breast bones, breast thaw and cooking losses and thigh cooking loss were lower (P ≤ 0.05) for caged hens than for free range hens. Free range hens had heavier (P ≤ 0.05) gizzards (33.9 ± 1.04 vs. 30.5 ± 0.73) and bones and a lower (P ≤ 0.05) breast meat percentage (47.3 ± 0.94 vs. 51.7 ± 1.35). Meat redness (a*) (0.54 ± 0.222 vs. 1.40 ± 0.135) and hue angle value, skin redness (a*), breast and thigh, Warner-Bratzler shear force (WBSF) values (breast: 12.37 ± 0.411 vs. 17.10 ± 0.751, thigh: 29.68 ± 0.306 vs. 39.75 ± 0.826), breast moisture and thigh ash content were lower (P ≤ 0.05) for caged hens than free range hens. Caged hens had higher (P ≤ 0.05) thigh thaw loss and breast ash content than free range hens. Canola-fed hens had higher (P ≤ 0.05) drum percentages, breast bone weights and percentages, with lower (P ≤ 0.05) thigh and breast meat percentages. Canola-fed hens had lower (P ≤ 0.05) thaw losses, skin yellowness (b*) and Chroma values, breast fat content with higher cooking losses, skin redness (a*) and hue angle value, as well as breast WBSF (12.37 ± 0.411 vs. 15.43 ± 0.600). Palmitic acid, stearic acid, heneicosanoic acid acid, palmitoleic acid, saturated fatty acids (SFA) (34.0 ± 0.56 vs. 38.7 ± 0.71), n-6:n-3 polyunsaturated fatty acids (PUFA) ratio (5.5 ± 0.13 vs. 7.2 ± 0.28), atherogenic index (IA), thrombogenic index (IT), delta-5 desaturase (D5D, elongase index and thiosterase index were lower (P ≤ 0.05) for canola-fed hen breast meat. Breast meat from conventionally fed hens had lower (P ≤ 0.05) myristic acid, lignoceric acid, nervonic acid, alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), PUFA:SFA ratio (0.7 ± 0.05 vs. 0.9 ± 0.02), n-3 PUFA (3.4 ± 0.31 vs. 5.1 ± 0.17), hypocholesterolemic:Hypercholesterolaemic (h/H), stearoyl-CoA desaturase 16 (SCD16) and stearoyl-CoA desaturase 18 (SCD18). The breast meat from conventionally fed hens had lower (P ≤ 0.05) metallic flavor than that from canola-fed hens. Strong positive correlations were observed for overall aroma with chicken (r = 0.965, P < 0.001) and brothy aroma (r = 0.827, P < 0.001); overall aroma with overall flavor (r = 0.680, P < 0.001), chicken flavor (r = 0.668, P < 0.001) and brothy flavor (r = 0.548, P = 0.006); initial juiciness with sustained juiciness (r = 0.771, P < 0.001) and tenderness (r = 0.537, P = 0.007); sustained juiciness with tenderness (r = 0.790, P < 0.001) and chewiness with residue (r = 0.783, P < 0.001). Whilst strong negative correlations were observed for: sustained juiciness with chewiness (r = -0.655, P = 0.001) and residue (r = 0.783, P < 0.001) and for tenderness with chewiness (r = 0.845, P < 0.001) and residue (r = -0.855, P < 0.001). Results of this study highlight that a free range production system when compared to a conventional cage system increased undesirable carcass and physical meat traits of spent laying hens. On the other hand, canola meal inclusion incorporates beneficial health aspects without affecting the sensory profile of meat derived from spent laying hens, both groups of hens being reared in battery cage system. Spent laying hen breasts can be consumed as a functional food (especially canolafed) since the fat content and composition was observed to be close to that which is recommended for a healthy diet.
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Farmers' perceptions of insect pests in the Eastern Cape maize-based cropping systems and the effects of crop residue management on insect pest populations
- Authors: Kadango, Tendayi Lovemore
- Date: 2018
- Subjects: Cropping systems Crop residue management Corn -- Diseases and pests
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6202 , vital:29507
- Description: Maize (Zea mays L.) is one of the most important crops in South Africa that is cultivated for food, feed and as a cash crop. Maize in the Eastern Cape is typically grown for consumption and the Province is one of the least producers owing to small landholdings, poor production conditions and pests. This study investigated: (i) the different maize cropping systems smallholder farmers practice in the Eastern Cape (EC), (ii) the major maize insect pests within the identified cropping systems, (iii) the perceptions of Eastern Cape smallholder maize farmers on the effects of insect pests, and (iv) the effects of crop residues on insect pests’ population dynamics. Four major cropping systems namely: maize sole cropping without rotations by government sponsored farmers (GCP) (94 percent), maize intercropping without rotations by independent farmers (IF) (79 percent), maize sole cropping without rotations by IF (67 percent) and maize intercropping without rotations by GCP (61 percent) were identified. The choice of a cropping system by the smallholder farmers was significantly influenced by source of sponsorship, the difference in their district localities, tenure system, availability of inputs and farming equipment, percentage of farmland farmers allocate to maize, maize varieties, farming experience, fallow operations and access to irrigation facilities. The major constraints faced by the farmers in maize production are the attack by insect pests, weeds competition, drought, the lack of fencing around the fields and destruction by mammals. The major insect pests identified were stalk borers (Busseola fusca, Chilo partellus), cutworms (Agrotis spp.), aphids (Rhopalosiphum maidis), bollworms (Helicoverpa armigera) and weevils (Sitophylus spp.). The most popular control measures employed were the use of GM maize and pesticides. Results from the field trial showed that field crickets were the major ground dwelling insect pests observed followed by bollworms and cutworms. However, there were no significant influence of residue retention on the insects’ diversity indices, richness, and evenness. Above ground insects sampling revealed the domination by four major insects namely, cutworms, maize stalk borer, bollworms, and spotted stalk borer. Residue management significantly influenced the infestation by spotted stalk borer only on maize plots. However, the general trend was that there was less infestation by the insects in plots where residues were retained than the ones with residue removed. Results from the study indicate that government sponsorship is significantly influencing the maize cropping systems of the smallholder farmers of the Eastern Cape.
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Household's perceptions and determinants of participation in harvesting rangeland products :|bthe case of Dyamala community, Raymond Mhlaba Local Municipality, Eastern Cape Province, South Africa
- Authors: Mdiya, Lwandiso
- Date: 2018
- Subjects: Rangelands -- South Africa -- Eastern Cape Communal rangelands -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/9187 , vital:34303
- Description: The study reviews the household’s perceptions and determinants of sustainable products harvesting. Communal rangelands are vast natural landscapes in the form of grasslands, shrubs, woodlands, wetlands and deserts with multiple functions to the rural households. Most rural communities share boundaries and interact with rangelands for multiple socioeconomic and environmental reasons. Since most of these interactions are external to the price mechanism, the actual contribution of rangelands to communities has largely been missed. In an effort to appraise and explore the communal rangeland contribution to households, a study from Dyamala community in the Raymond Mhlaba Local Municipality under Amathole District in Eastern Cape was conducted using cross-sectional data. Descriptive results revealed that the majority of the respondents (71 percent) from the study area positively perceived communal rangelands as safety nets. however, there also emerged a fair share of challenges namely, (bad spirit, host predators, compete with arable land) leading to negative perceptions towards communal rangelands. It was also evident that, the majority of respondents from the study area use communal rangelands for fuel wood, construction poles, traditional medicine, with minor harvests of wild food (flora and fauna) and thatch grass. The results of the study also revealed that, rural people depend more on social grants for their income followed by incomes from remittances, agricultural activities and communal rangelands. However, it was established from the results that though communal rangelands provided commercial products capable of generating household income, rangeland users trading such products were receiving meagre incomes. This might be caused by the lack of institutional support to rural households thus, the low incomes received from communal rangelands. To that effect, main communal rangeland products such as, fuel wood, poles and medicine were cited as being more valuable for local domestic use than for the external market. Regression estimates further indicated that participation in communal rangeland products harvesting is more conditioned by perception-related factors as compared to socioeconomic attributes of rural households worth understanding for strategic targeting to promote their conservation. The extant literature and the study results, evidently show that communal rangelands provide a livelihood among rural households although it has a low direct household income potential. Therefore, the respondents were of the view that the use of campaigns targeting several perceptions (such as communal rangelands act as a source of medicinal plants, arable land and income etc) as suggested by the regression estimates may be very useful. The support from the extension department and further research may be necessary for purposes of quantifying harvestable rangeland products capable of enhancing rural livelihoods. Moreover, the observed low income potential of communal rangeland products suggests several technical and institutional challenges worth addressing to promote value addition of rangeland products.
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Image processing and data analysis tools of a remote sensing-based euthrophication monitoring system
- Authors: Chamunorwa, Brighton
- Date: 2018
- Subjects: Eutrophication Image processing
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10210 , vital:35376
- Description: Numerous surface water bodies in South Africa face serious challenges of eutrophication despite several initiatives from government to solve the problem. Government efforts have not been successful particularly because of three issues: 1) insufficient and inconsistent water quality data and 2) the costly nature of collecting this data. Third, the limited uptake of remote sensing based technologies in water quality management due to lack of skills, as well as the lengthy and complex procedures involved in retrieving water quality parameters. This thesis aims to explore the possibilities of using satellite data and simple software for mapping and collecting water quality data. The broad goal was to determine the function of software dedicated to meet the requirements of a remote sensing-based eutrophication-monitoring system. Two specific goal were set in this study: 1. To extract software requirements from available eutrophication management documentation. This was necessary to determine the functions of the dedicated software that matches the legislative requirements and 2. To determine a design capable of handling spatial and temporal requirement of a remote sensing based eutrophication-monitoring system. The study applied Goal Based Requirement Analysis Model [GBRAM] model to extract goals from the National Eutrophication Monitoring Programme [NEMP] implementation plan document and recent publication on remote sensing of water quality monitoring conducted in South Africa. Afterwards, the study used object-oriented concepts to model suitable data objects and processes to implement spatial-temporal requirements of a remote sensing-based eutrophication-monitoring system. Based on the study findings the following are essential functions of a remote sensing based eutrophication-monitoring system. A graphical user interface that allows the user to set up a monitoring programming. Automated image processing procedures. Data assessment methods used to generate eutrophication status information. Numerous display options for viewing data in several perfectives.
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In silico analysis, isolation and kinetic characterisation of red algae (Rhodophyta) catalases
- Authors: Nodangala, Sinovuyo
- Date: 2018
- Subjects: Red algae Marine algae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14626 , vital:40024
- Description: Catalase (EC: 1.11.1.6) is produced by almost all aerobic organism ranging from bacteria to human and is an essential antioxidant enzyme that catalyses the conversion of hydrogen peroxide to water and molecular oxygen, therefore neutralising hydrogen peroxide toxicity. The present study aimed to purify and characterise catalase from Pachymenia orbitosa, a marine red algae found in the Algoa Bay region of South Africa. Bioinformatics analysis was performed to confirm the presence of a catalase gene in the red algae genome. In silico analysis of the Chondrus crispus genome was performed to predict the functional and structural characterisation of the protein encoded by the gene. The Pachymenia orbitosa catalase enzyme was purified to homogeneity using 60% ammonium sulphate precipitation and Sephacryl S-200 gel filtration chromatography. InterProScan confirmed that the Chondrus crispus genome encodes a catalase protein, which is from the mono-functional and heme-dependent catalase-like superfamily. The purified Pachymenia orbitosa catalase enzyme displayed a specific activity of 23 000 units per mg of protein with a 14.94% recovery and 222.91 fold purification. Sodium dodecyl sulphatepolyacrylamide gel electrophoresis indicated a single band, with a molecular weight of around 50kDa. The catalase enzyme exhibited a maximum activity at pH 7 and a temperature of 30℃. It was stable up to 40℃ and rapidly denatured at temperatures above this. The Km and Vmax values for the purified catalase, using hydrogen peroxide as a substrate, were determined from the Lineweaver-Burk plot to be 22.22mM and 1.11x10-4mM.min-1 , respectively, while from the Hanes-Woolf plot, to be 23.4mM and 1.17x10-4mM.min-1 , respectively. The Heme catalase inhibitor (ferricyanide) inhibited the enzyme activity markedly, while sodium chloride and citric acid had only a slight inhibitory effect. Copper sulphate showed a slight stimulatory effect. The physiochemical properties suggest a good application potential in both the pharmaceutical and food industries
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Investigation of strategies employed in rural households to improve food security in Raymond Mhlaba Local Municipality : a case of Zihlahleni Location in Middledrift, Eastern Cape Province
- Authors: Gqozo, Odwa
- Date: 2018
- Subjects: Food security -- South Africa -- Eastern Cape Rural development -- South Africa -- Eastern Cape Households -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10758 , vital:35752
- Description: Eastern Cape is one of the provinces experiencing a rapid increase in food prices while household income is increasing at a slower rate. Against this background, the main objective of this study was to investigate strategies used by rural households to improve food security in Raymond Mhlaba Local Municipality formally known as Nkonkobe in the Eastern Cape Province, South Africa. Data were collected from 100 households using a questionnaire as the main instrument by using simple random sampling. Data were analyzed by employing simple descriptive statistics to describe household food security. Results revealed that most (50.3percent) households that were interviewed were male headed and unemployment was high (73.6percent). Moreover, the average age of the interviewed household heads was 59 years. Most (68percent) of the households owned home gardens and had access to arable land which was not being cultivated. Most (87percent) households indicated that lack of capital was the main cause of food security and depended on government grants. Most (100percent) of the interviewed household heads depend mostly on food purchases rather than their own production. The recommendation is that the government should continue fostering its agenda of improving agriculture as a strategy in rural households for curbing food insecurity.
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Investigation of the subsurface geology using time domain, magnetic and electrical resistivity geophysical techniques in the Karoo basin at Beaufort west, Western Cape Province, South Africa
- Authors: Ntunja, Asanda
- Date: 2018
- Subjects: Geology Geophysics
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/14659 , vital:40034
- Description: Beaufort West lies in the Central Karoo Basin and is specifically situated in the Poortjie Member of the Teekloof Formation in the Beaufort Group. The Teekloof Formation was deposited in a floodplain environment and it consists of alternating bluish grey mudstone and very fine to medium grained sandstone. The sediments of the Karoo Basin were intruded by numerous dolerite sills and dykes during a period of extensive magmatic activity over the whole South African subcontinent when the break-up of Gondwanda occurred. This led to a continuous jointing of the sedimentary rocks and the jointing resulted in rocks that are prone to weathering. Weathering that occurred in Beaufort West resulted in the formation of alluvium, calcrete, scree and hard pan deposits which overlay most of the ground surface. The joints in rocks paved way for groundwater storage in the sedimentary beds as sediments of the Karoo Basin lack significant primary porosity. Geophysical surveys were done in order to determine a suitable site to locate and drill a deep borehole to the White Hill Formation in order to extract shale gas that is proposed to be present in the area, thereafter determine sites for monitoring boreholes for groundwater and also look for area where potential groundwater might be present. This then requires geophysical investigations of the surface and subsurface geology of the area prior to drilling so as to locate any features such as dolerite intrusions which may hinder the drilling process and locate shallow aquifers, which will tend to be monitored before and during fracking. Five lines of varying lengths from 2-6 km and different orientation were surveyed using geophysical techniques which included the time domain, electrical resistivity as well as the magnetic methods. The geophysical investigations were conducted in order to fulfil the main vii objectives and aims of the study. The techniques were then complemented by XRF, petrography and density analyses. The time domain method reveals that Lines 1 and Line 2 comprises of rocks with low resistivity values of less than 30 Ωm. These two lines were more conductive towards the east and northeast side of the study site and the resistivity tends to increase towards the south and west. Line 4 appeared to be more conductive towards the south-east of the line. Lines 3 and 5 showed high resistivity values with Line 5 being the most resistive suggesting that the underlying strata is consolidated, dry and hard. The resistivity in all the lines surveyed showed an increase with increasing depth. The depth of investigation was approximately up to 150 m. The electrical resistivity results were only obtained from Line 1 and Line 2. The results, which complement the time domain results, suggest that the two lines indeed comprise of rocks which exhibit low resistivity values. This then implies that the rocks in the vicinity are fractured and the fractures might be field with groundwater and possibly contain some conductive minerals such as sodium oxide (Na2O) as supported by XRF results. This method also reveals that along Line 1, there are individual bodies of high resistivity values. The probing depth of about 78 m was achieved for the electrical resistivity survey. The magnetic data indicate that the magnetic intensity does not vary much across lines 3, 4 and 5 and there is not much change in lithology with depth and lateral extent. The area covered by Lines 1 and 2, and the additional eleven fill in lines has several prominent magnetic highs that are inferred to be due to dolerite intrusions in the sandstones and these bodies may be connected at depth. One of these anomalies which trends east-west direction partially coincides with a mapped dolerite intrusion. Some areas with sandstones also exhibit high viii magnetism which is due to about 3.3% content of Fe2O3 present in the sandstones as seen from XRF. This is probably resulted from weathering of magnetite in dolerite intrusions. Petrography results obtained from samples collected in the field reveal that there is an abundance of quartz in sandstones and siltstones. Quartz arenite also contained about 50% of feldspar, containing both plagioclase and K-feldspar. The sandstones of the Teekloof Formation (Beaufort West) have undergone calcite replacement where the calcite matrix replaced most or all of the clay matrix between the mineral grains. The fractures in rocks were seen and it was inferred that they are due to the present cleavages in feldspar and weathering of feldspar in sandstones. Through X-ray Fluorescence (XRF) analysis, it was revealed that the rocks contained a high percentage of Na2O. XRF also showed that these rocks were under low chemical weathering which led to the formation of new minerals in rock as other minerals such as feldspar weather away. This resulted in quartz being the most dominant mineral present as it is not prone to chemical weathering and thus the rocks were proven to be chemically matured. Thirty one rock samples were collected from the field in order to determine the density and porosity measurements. The fine to medium grained grey sandstones show an average density of 2.597 g/cm3 and a porosity of 1.4 %. The brownish grey sandstone have an average density of 2.546 g/cm3 and porosity of 2.9 % and the brown sandstones exhibit an average of 2.584 g/cm3 and a porosity 1.46 %. Dolerite has an average density of 2.970 g/cm3 and porosity of 0.5 % and siltstones have a density of 2.595 g/cm3 and porosity of 1.38 %. The brownish grey sandstones have the highest porosity and the grey sandstone and siltstone have the least porosity after the dolerite.
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Isolation and characterization of E. coli and Campylobacter spp. from diarrhoeal samples collected from selected hospitals in Amathole District Municipality, Eastern Cape, South Africa
- Authors: Omolajaiye, Sunday Abraham
- Date: 2018
- Subjects: Escherichia coli infections Campylobacter infections Diarrhea
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/6213 , vital:29515
- Description: Approximately 2-4 billion cases of infectious diarrhoea occur every year, with the highest numbers recorded in sub-Saharan Africa. It remains the most common public health issue among children in developing nations. The purpose of this research was to unfold the prevalence of diarrhoeagenic E. coli and Campylobacter pathotypes as well as elucidate their antibiogram characteristics in diarrhoeal stool samples collected in some medical facilities in Eastern Cape Province, South Africa. Two hundred stool samples were collected from both inpatients and outpatients from male and females of all age groups attending selected medical facilities in the study area. Isolation and characterization of both organisms were done using culture based and molecular methods. Antibiotic susceptibility patterns of identified isolates were determined against a panel of 12 antimicrobial agents. One hundred and twenty presumptive E. coli isolates and 42 presumptive isolates of Campylobacter spp. Were isolated. Eighty-two percent (82 percent) of the presumptive E. coli isolates were confirmed as E. coli while 46.3 percent belonged to Campylobacter spp. Pathotyping of the diarrhoeagenic E. coli isolates by Polymerase chain reaction (PCR) showed the following prevalences: DAEC 43 (32 percent), EHEC 18 (17 percent), EIEC 11 (10 percent) and EPEC 18 (17 percent). EAEC and ETEC were not detected, while for Campylobacter spp. 37 (88 percent) were C. jejuni, and C. coli was not detected. A total of 12 (32.4 percent) of the confirmed Campylobacter jejuni isolates were found to possess the fliM gene, 9 (24.3 percent) possessed the flhA gene and only 6 (16.2 percent) harboured the gene flgE2. None were positive for the flaA, flab and flhB genes.The antibiotic resistance patterns observed among the E. coli isolates were high against ampicillin (98.1 percent), chloramphenicol (94.3 percent) and tetracycline (90.6 percent). For Campylobacter spp., resistance observed were: chloramphenicol (91.6 percent), tetracycline (25.2 percent), erythromycin (49.6 percent) and gentamycin (56.4 percent). A lesser resistance against imipenem (35.9 percent) and quinolone (ciprofloxacin) (45.5 percent) were exhibited by the E.coli isolates. 10.8 percent and 20.3 percent of the Campylobacter isolates were resistant to imipenem and ciprofloxacin respectively. The presence of chloramphenicol (CatA1) and tetracycline (tetA) resistance genes were detected in 94 percent and 89 percent of E. coli isolates respectively while 98 percent of Campylobacter spp. Harboured the catA1 resistance gene. It could be deduced from this study that E. coli and Campylobacter spp. are predomiant enteric pathogens as the etiologic agents of diarrhoea in the study community, and that their antimicrobial resistance is high in the study location. The need to develop strategies to prevent infection and control resistant organisms is evident.
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Metabolic Systems Biology: Uncovering operations of cell and metabolism
- Authors: Marange , Israel Yeukai
- Date: 2018
- Subjects: Systems biology
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/19120 , vital:39881
- Description: The aim of this work is to analyse the technique for formulating cellular metabolism in living organisms. It also focuses on developing models of cellular metabolic systems. A sequence of biochemical reactions termed metabolic branched pathways that occur inside a cell, are of particular interest.Mathematical modelling is used as a tool to examine and analyse the metabolism of viral dynamics for the ends of this research. Dynamic mathematical models provide an important means with which to investigate the cell cycle control system. The derivation of the ordinary differential equations (ODEs) is useful in describing and analysing the metabolic network structures of branched flux pathways, as well as enzyme-substrate,reciprocal-action networks which control the cell cycle. Different general and specific factors affecting metabolic rate are identified and explained
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Multi-temporal analysis of changes in vegetation distribution in the Great Fish River Game Reserve, Eastern Cape Province, South Africa :1982-2012
- Authors: Dikweni, Sipho
- Date: 2018
- Subjects: Climatic changes -- South Africa|zEastern Cape Biodiversity conservation
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10511 , vital:35550
- Description: Great Fish River Game Reserve plays an important role in curtailing the ever-increasing biodiversity declines in Eastern Cape Province and South Africa at large. Though this area plays an important role in the conservation of natural biodiversity, it has been observed that it is undergoing considerable changes with regards to conditions and composition of vegetation cover. These changes signal a decline in the capacity of the Great Fish River Game Reserve to support wildlife population. In this study, remote sensing was used to investigate multi-temporal changes in vegetation distribution in this particular reserve over a period of 30 years (1982-2012). A supervised classification was carried out to classify four Landsat images including; Landsat TM, Landsat ETM and Landsat 8 imagery of 1984, 1992, 2002 and 2013 respectively to map historical and present vegetation conditions and distribution in the Great Fish River Game Reserve. A comparative examination of the classified images showed that there were significant changes in the composition and structure of vegetation with much of the palatable plant species being driven to extinction. The results showed that herbivory pressure inconjuction with climate variability has subsequently resulted in a decrease of the supporting potential of the reserve to sustain wildlife due to mortality of the most preferred plant species and abundant increase of non-palatable plant species. As grazing and browsing intensity increased, there was a decline in regenerative potential of the selected plant species by wild herbivores and successful increase in abundance of the non-palatable plant species. The results of this investigation suggest that the current increase in wildlife population will facilitate the deterioration of habitat condition to support wildlife up to the point of no recovery.
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Perceptions, determinants and consumption patterns of indigenous fruits and vegetables in rural areas : evidence from Mutale Local Municipality, Limpopo Province, South Africa
- Authors: Nengovhela, Rudzani
- Date: 2018
- Subjects: Vegetables in human nutrition Indigenous crops Food security
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/10123 , vital:35356
- Description: Rural households across South Africa experience food and nutrition insecurity. Given the fact that indigenous fruits and vegetables (IF&Vs) have numerous health benefits including their wide availability and accessibility in rural areas, these indigenous varieties can significantly contribute to food and nutrition security in rural household. However, the consumption of IF&Vs in recent years has generally remained low and has been declining. The present study investigated the perceptions of IF&Vs, consumption patterns and determinants of IF&V consumption among 200 rural households (n = 200) from 10 villages within the Mutale Local Municipality of Limpopo Province, South Africa. The results revealed that, respondents held overwhelmingly positive perceptions of IF&Vs. The majority of the respondents believed that IF&Vs were healthier, less expensive and more visually attractive than exotic varieties. Consumption of the selected IF&Vs was generally high among the sample size. There were more households that consumed each of the selected IF&Vs than those that did not consume. Most of the selected IF&Vs were consumed only in summer and consumed on a weekly basis rather than daily or monthly basis. Age, marital status, occupation, education level and household size, as well as, perceptions of indigenous fruits’ longevity promotion, health beneficiation and relative visual attractiveness were found to be significant determinants of indigenous fruit consumption. On the other hand, the education level, in addition to perceptions of indigenous vegetables’ comparative healthiness, longevity promotion, health beneficiation and preparative ease were significant determinants of respondents’ indigenous vegetable consumption.
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