Keychains and preferential fuzzy sets with applications
- Authors: Mahlasela, Zuko
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435933 , vital:73213 , DOI 10.21504/10962/435935
- Description: In this thesis, we study the preferentiality behaviour of choices under uncertainties using keychains, where a keychain is defined as an (n+ 1)-tuple of non-increasing real numbers in the unit interval, I= [0, 1]. We look at the representations of uncertainties or sets defined by vague properties using the idea of keychains, pins and pinned flags. We then apply the ideas of preferential fuzzy sets to voting patterns, economics and decision making. For voting patterns, we simulate mock trials to investigate the behaviours of choices of different individuals, the outcomes of such voting and make specific conclusions about voting strategies. It can be argued that preferentiality in voting can enhance the democratic processes in national elections. This thesis contains various representations of keychains such as binary digits, weight order, lattice and simplex representations. Another useful aspect of keychains and preferential fuzzy sets is to study the outcomes of decision making linking it to the study of keychains and finite fuzzy sets. We envisage that this study will throw light on computational aspects of any countable situations. , Thesis (PhD) -- Faculty of Science, Mathematics, 2024
- Full Text:
- Date Issued: 2024-04-05
- Authors: Mahlasela, Zuko
- Date: 2024-04-05
- Subjects: Uncatalogued
- Language: English
- Type: Academic theses , Doctoral theses , text
- Identifier: http://hdl.handle.net/10962/435933 , vital:73213 , DOI 10.21504/10962/435935
- Description: In this thesis, we study the preferentiality behaviour of choices under uncertainties using keychains, where a keychain is defined as an (n+ 1)-tuple of non-increasing real numbers in the unit interval, I= [0, 1]. We look at the representations of uncertainties or sets defined by vague properties using the idea of keychains, pins and pinned flags. We then apply the ideas of preferential fuzzy sets to voting patterns, economics and decision making. For voting patterns, we simulate mock trials to investigate the behaviours of choices of different individuals, the outcomes of such voting and make specific conclusions about voting strategies. It can be argued that preferentiality in voting can enhance the democratic processes in national elections. This thesis contains various representations of keychains such as binary digits, weight order, lattice and simplex representations. Another useful aspect of keychains and preferential fuzzy sets is to study the outcomes of decision making linking it to the study of keychains and finite fuzzy sets. We envisage that this study will throw light on computational aspects of any countable situations. , Thesis (PhD) -- Faculty of Science, Mathematics, 2024
- Full Text:
- Date Issued: 2024-04-05
Development of a numerical geohydrological model for a fractured rock aquifer in the Karoo, near Sutherland, South Africa
- Authors: Maqhubela, Akhona
- Date: 2024-04
- Subjects: Groundwater -- South Africa -- Northern Cape , Hydrogeology -- South Africa -- Northern Cape , Remote sensing , Geographic information systems
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/64163 , vital:73659
- Description: The regional scale method in groundwater storage observation introduces uncertainties that hinder the evaluation of the remaining lifespan of depleted aquifers. The scarcity of precipitation data presents significant global challenge, especially in semi-arid regions. This study constructs a regional numerical hydrogeological model that identifies the potential impacts of climate change on the water balance for the South African Gravimetric Observation Station in Sutherland. The purpose of this study is to understand mechanisms controlling groundwater in the fractured rock aquifer. The climate data from the Weather forecast data over the last ten years was collected from the South African Weather Service. and groundwater levels data assessed the potential impacts of climate change on water balance components, especially precipitation and evapotranspiration. Precipitation is the primary recharge parameter in this study and had the highest level recorded in winter, with May having the highest precipitation rates of 24,62mm. The instrument conducted two profile investigations in a single day to detect geological abnormalities at various depths, achieving an impressive accuracy of up to 0.001 mV. The fact that groundwater flows from regions of higher hydraulic heads to areas of lower hydraulic charges, confirms that riverbeds in Sutherland act as preferential conduits for subsurface recharge. The profile and processed geophysical maps show low chances of getting groundwater in this observed area due to extensively great depth, approximately 150 – 210 m. The river package from MODFLOW model shows little inflow to the study nearby well locations. These model results showed a negative difference between water flowing in and out of the system of about -7m3 between 2002 and 2020. Groundwater flows faster at borehole five, where the hydraulic conductivity is large. The resulting regional hydrogeological model offered valuable insights into how climate change might influence the distribution and accessibility of groundwater resources. In the context of Sutherland, a negative groundwater budget value signaled that groundwater extraction or consumption surpassed the natural replenishment or recharge of the aquifer. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2024-04
- Authors: Maqhubela, Akhona
- Date: 2024-04
- Subjects: Groundwater -- South Africa -- Northern Cape , Hydrogeology -- South Africa -- Northern Cape , Remote sensing , Geographic information systems
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/64163 , vital:73659
- Description: The regional scale method in groundwater storage observation introduces uncertainties that hinder the evaluation of the remaining lifespan of depleted aquifers. The scarcity of precipitation data presents significant global challenge, especially in semi-arid regions. This study constructs a regional numerical hydrogeological model that identifies the potential impacts of climate change on the water balance for the South African Gravimetric Observation Station in Sutherland. The purpose of this study is to understand mechanisms controlling groundwater in the fractured rock aquifer. The climate data from the Weather forecast data over the last ten years was collected from the South African Weather Service. and groundwater levels data assessed the potential impacts of climate change on water balance components, especially precipitation and evapotranspiration. Precipitation is the primary recharge parameter in this study and had the highest level recorded in winter, with May having the highest precipitation rates of 24,62mm. The instrument conducted two profile investigations in a single day to detect geological abnormalities at various depths, achieving an impressive accuracy of up to 0.001 mV. The fact that groundwater flows from regions of higher hydraulic heads to areas of lower hydraulic charges, confirms that riverbeds in Sutherland act as preferential conduits for subsurface recharge. The profile and processed geophysical maps show low chances of getting groundwater in this observed area due to extensively great depth, approximately 150 – 210 m. The river package from MODFLOW model shows little inflow to the study nearby well locations. These model results showed a negative difference between water flowing in and out of the system of about -7m3 between 2002 and 2020. Groundwater flows faster at borehole five, where the hydraulic conductivity is large. The resulting regional hydrogeological model offered valuable insights into how climate change might influence the distribution and accessibility of groundwater resources. In the context of Sutherland, a negative groundwater budget value signaled that groundwater extraction or consumption surpassed the natural replenishment or recharge of the aquifer. , Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2022
- Full Text:
- Date Issued: 2024-04
Esibelekweni: Ingqokelela Yemibongo ngesiXhosa nangesiNgesi
- Authors: Busakwe, Yenzokuhle
- Date: 2023-10-13
- Subjects: Creative writing (Higher education) South Africa , Diaries Authorship , Books Reviews , South African essays (English) 21st century , Xhosa poetry 21st century
- Language: English , Xhosa
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424917 , vital:72193
- Description: My thesis is a collection of poems that is written in isiXhosa and English. It explores African spirituality, my relationship with God, heartache from romantic and platonic relationships. I make use of dual languages because some themes that I write about such as African spirituality I find words that capture their truest emotion in my Xhosa vocabulary, and I cannot find them in English. My poems use the narrative form because it allows me to tell stories through poetry without having to commit my writing to musicality or rhyming that a lyric poetry normally has. My work is shaped by writers such as Kate Beinhemer, Mangaliso Buzani, Amy Saul Zerby, Nontsizi Mgqwethio, Simphiwe Nolutshungu and Oiu Miaojin. Buzani makes use of images and few lines in his writing but still manages to capture a story with brevity. Saul-Zerby makes use of text lingo in some of her poems, and I make use of it to close a gap that I have identified with the books that I was reading that are all written in a formal and serious format. Mgqwetho’s poems explore Christianity and African Spirituality which is one of the subjects that my work is exploring too but in a manner that differs. I talk about how they have been my guidance instead of praising their powers like Nontsizi normally does in her poems. Simphiwe Nolutshungu’s poems has influenced the structure of my poems. Fairy tales written by writers like Kate helps my writing to bring to life issues that sound too dreamy to be true but have manifested as visions and memories that I cannot wipe out from my conscience. Oiu Miaojin’s novel “Last words from Montmantre” I am fascinated by how the writer detail emotions such as vulnerability and heartbreak in his storytelling. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2023
- Full Text:
- Date Issued: 2023-10-13
- Authors: Busakwe, Yenzokuhle
- Date: 2023-10-13
- Subjects: Creative writing (Higher education) South Africa , Diaries Authorship , Books Reviews , South African essays (English) 21st century , Xhosa poetry 21st century
- Language: English , Xhosa
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/424917 , vital:72193
- Description: My thesis is a collection of poems that is written in isiXhosa and English. It explores African spirituality, my relationship with God, heartache from romantic and platonic relationships. I make use of dual languages because some themes that I write about such as African spirituality I find words that capture their truest emotion in my Xhosa vocabulary, and I cannot find them in English. My poems use the narrative form because it allows me to tell stories through poetry without having to commit my writing to musicality or rhyming that a lyric poetry normally has. My work is shaped by writers such as Kate Beinhemer, Mangaliso Buzani, Amy Saul Zerby, Nontsizi Mgqwethio, Simphiwe Nolutshungu and Oiu Miaojin. Buzani makes use of images and few lines in his writing but still manages to capture a story with brevity. Saul-Zerby makes use of text lingo in some of her poems, and I make use of it to close a gap that I have identified with the books that I was reading that are all written in a formal and serious format. Mgqwetho’s poems explore Christianity and African Spirituality which is one of the subjects that my work is exploring too but in a manner that differs. I talk about how they have been my guidance instead of praising their powers like Nontsizi normally does in her poems. Simphiwe Nolutshungu’s poems has influenced the structure of my poems. Fairy tales written by writers like Kate helps my writing to bring to life issues that sound too dreamy to be true but have manifested as visions and memories that I cannot wipe out from my conscience. Oiu Miaojin’s novel “Last words from Montmantre” I am fascinated by how the writer detail emotions such as vulnerability and heartbreak in his storytelling. , Thesis (MA) -- Faculty of Humanities, School of Languages and Literatures, 2023
- Full Text:
- Date Issued: 2023-10-13
The effectiveness of networking and collaboration in creative hubs: a case of Hub@Goethe
- Authors: De Beer, Magdalena Gertruda
- Date: 2022-04-06
- Subjects: Cultural industries South Africa , Cultural industries Economic aspects South Africa , Economic development projects South Africa , Social entrepreneurship South Africa , Creative ability Economic aspects South Africa , Social capital (Sociology) South Africa , Social networks South Africa , Hub@Goethe
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/284504 , vital:56069
- Description: This research took the form of a case study investigating the effectiveness of a single hub in South Africa, namely Hub@Goethe in Johannesburg. The context of the creative economy and creative industries provided insight into the experiences of creative cultural labourers in the new economic model. The context emphasised the research problem which considered the difficulties experienced by creative and cultural entrepreneurs and their career paths who, through labour precarity, remain isolated from the market, without access to physical spaces, network connections and business knowledge to realise their business ideas. The literature reviewed revealed how co-working office spaces, creative spaces and hubs provide creative entrepreneurs with the spatial infrastructure, amenities, and network access to mitigate challenges in the creative cultural sectors. These spaces offer a multitude of different amenities which is specific to their community’s needs. Guided by the theory of social capital and structural holes reviewed in the literature, the effectiveness was assessed by the hub’s ability to provide network access benefits or resource endowments. The research looked at whether the hub could provide creative cultural entrepreneurs with resource benefits such as a) access to social interactions, collaboration, and knowledge sharing, b) access to business or professional skills-based education programmes and mentorship, c) access to market and d) generation both social and economic benefit. The research adopted a qualitative approach, seeking insights into the creative entrepreneurs’ experiences at the hub utilising one-to-one interviews. The thematic analysis confirmed that the hub was effective overall in providing entrepreneurs with access to benefits or resource endowments embedded in the network, confirming that hubs may be an effective tool in mitigating difficulties experienced by creative entrepreneurs in the creative industries. The research also showed areas of improvement where the hub could increase its experienced effectiveness, especially in reference to routes to market. The research findings inferred the importance of physical space, proximity and accessibility has on collaborative practices amongst creative entrepreneurs within the hub space. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2022
- Full Text:
- Date Issued: 2022-04-06
- Authors: De Beer, Magdalena Gertruda
- Date: 2022-04-06
- Subjects: Cultural industries South Africa , Cultural industries Economic aspects South Africa , Economic development projects South Africa , Social entrepreneurship South Africa , Creative ability Economic aspects South Africa , Social capital (Sociology) South Africa , Social networks South Africa , Hub@Goethe
- Language: English
- Type: Academic theses , Master's theses , text
- Identifier: http://hdl.handle.net/10962/284504 , vital:56069
- Description: This research took the form of a case study investigating the effectiveness of a single hub in South Africa, namely Hub@Goethe in Johannesburg. The context of the creative economy and creative industries provided insight into the experiences of creative cultural labourers in the new economic model. The context emphasised the research problem which considered the difficulties experienced by creative and cultural entrepreneurs and their career paths who, through labour precarity, remain isolated from the market, without access to physical spaces, network connections and business knowledge to realise their business ideas. The literature reviewed revealed how co-working office spaces, creative spaces and hubs provide creative entrepreneurs with the spatial infrastructure, amenities, and network access to mitigate challenges in the creative cultural sectors. These spaces offer a multitude of different amenities which is specific to their community’s needs. Guided by the theory of social capital and structural holes reviewed in the literature, the effectiveness was assessed by the hub’s ability to provide network access benefits or resource endowments. The research looked at whether the hub could provide creative cultural entrepreneurs with resource benefits such as a) access to social interactions, collaboration, and knowledge sharing, b) access to business or professional skills-based education programmes and mentorship, c) access to market and d) generation both social and economic benefit. The research adopted a qualitative approach, seeking insights into the creative entrepreneurs’ experiences at the hub utilising one-to-one interviews. The thematic analysis confirmed that the hub was effective overall in providing entrepreneurs with access to benefits or resource endowments embedded in the network, confirming that hubs may be an effective tool in mitigating difficulties experienced by creative entrepreneurs in the creative industries. The research also showed areas of improvement where the hub could increase its experienced effectiveness, especially in reference to routes to market. The research findings inferred the importance of physical space, proximity and accessibility has on collaborative practices amongst creative entrepreneurs within the hub space. , Thesis (MBA) -- Faculty of Commerce, Rhodes Business School, 2022
- Full Text:
- Date Issued: 2022-04-06
The design of a 21st century administrative headquarters for the city of Gqeberha
- Authors: Borchers, Spencer Phillip
- Date: 2022-04
- Subjects: Municipal buildings -- South Africa -- Gqeberha -- Designs and plans , Architecture, Modern -- 20th century -- Designs and plans
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/57443 , vital:57870
- Description: This treatise developed through an interest in 21st century office buildings and the impact they have on the well-being of occupants. The office of the 20th century disregarded well-being and was focused on efficiently accommodating the functions of the workplace in an effort to increase productivity. Today, many of these buildings inadequately provide for the basic biological, psychological, and social needs required for the work force of the 21 st century. The nature of the office has shifted to a more socially interactive and flexible environment which attempts to obtain productivity targets through nurturing the well-being of occupants. Research has determined that biological health can be supported through the optimization of building performance; psychological health can be supported through considering environmental psychology; and social health can be supported through instilling a robust corporate culture. This treatise takes a qualitative research approach to thoroughly interpret the informants and constraints of the site in order to design additions and alterations to the existing administrative headquarters for the Nelson Mandela Bay Municipality. The updated facility will consolidate the administrative functions of local government into one 21st century administrative headquarters, located on the sites of three current NMBM offices in Govan Mbeki Avenue. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2022
- Full Text:
- Date Issued: 2022-04
- Authors: Borchers, Spencer Phillip
- Date: 2022-04
- Subjects: Municipal buildings -- South Africa -- Gqeberha -- Designs and plans , Architecture, Modern -- 20th century -- Designs and plans
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/57443 , vital:57870
- Description: This treatise developed through an interest in 21st century office buildings and the impact they have on the well-being of occupants. The office of the 20th century disregarded well-being and was focused on efficiently accommodating the functions of the workplace in an effort to increase productivity. Today, many of these buildings inadequately provide for the basic biological, psychological, and social needs required for the work force of the 21 st century. The nature of the office has shifted to a more socially interactive and flexible environment which attempts to obtain productivity targets through nurturing the well-being of occupants. Research has determined that biological health can be supported through the optimization of building performance; psychological health can be supported through considering environmental psychology; and social health can be supported through instilling a robust corporate culture. This treatise takes a qualitative research approach to thoroughly interpret the informants and constraints of the site in order to design additions and alterations to the existing administrative headquarters for the Nelson Mandela Bay Municipality. The updated facility will consolidate the administrative functions of local government into one 21st century administrative headquarters, located on the sites of three current NMBM offices in Govan Mbeki Avenue. , Thesis (MArch) -- Faculty of Engineering, the Built Environment and Technology, School of Architecture, 2022
- Full Text:
- Date Issued: 2022-04
A guide for the use of tablet PCs for teaching and learning activities for in classroom and distance learning in South African schools
- Authors: Theunissen, Kristen Emma
- Date: 2021-10-29
- Subjects: Tablet computers South Africa Makhanda , Blended learning South Africa Makhanda , Computer-assisted instruction South Africa Makhanda , Educational technology Study and teaching South Africa Makhanda , Teachers In-service training South Africa Makhanda , Pedagogical content knowledge South Africa Makhanda , Education Effect of technological innovations on South Africa Makhanda , South Africa. Department of Basic Education , TPACK (Technological Pedagogical Content Knowledge)
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/191920 , vital:45179
- Description: Education in South Africa is said to be in crisis in recent years as many learners cannot pass standardised tests at the correct grade level. This has encouraged the South African Government and the Department of Basic Education (DBE) to introduce technology, specifically Tablet PCs, into education to improve learning outcomes in South African government schools. Furthermore, because of the coronavirus pandemic that started in 2020, educators were increasingly expected to find alternative, digital, online methods to continue teaching learners. Thus, the need for remote or distance education suddenly became an important factor in creating a need for online, remote learning. Against this backdrop this study aimed to determine how and in what ways educators could be supported to promote effective use of Tablet PCs both in the classroom and for distance learning. This study used Action Design Research to develop a guide based on both theory and the results gathered from the educator participants at a local secondary government school in Makhanda, South Africa. The finalised guide presents recommendations to educators, principals, and the DBE to promote acceptance and adoption of technology in the classroom and for distance learning. These recommendations include the provision of data, technological training and pedagogical support, a functioning community of practice, an online learning community of practice, and support from the DBE. Other enrichment factors were also recommended. , Thesis (MCom) -- Faculty of Commerce, Information Systems, 2021
- Full Text:
- Date Issued: 2021-10-29
- Authors: Theunissen, Kristen Emma
- Date: 2021-10-29
- Subjects: Tablet computers South Africa Makhanda , Blended learning South Africa Makhanda , Computer-assisted instruction South Africa Makhanda , Educational technology Study and teaching South Africa Makhanda , Teachers In-service training South Africa Makhanda , Pedagogical content knowledge South Africa Makhanda , Education Effect of technological innovations on South Africa Makhanda , South Africa. Department of Basic Education , TPACK (Technological Pedagogical Content Knowledge)
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10962/191920 , vital:45179
- Description: Education in South Africa is said to be in crisis in recent years as many learners cannot pass standardised tests at the correct grade level. This has encouraged the South African Government and the Department of Basic Education (DBE) to introduce technology, specifically Tablet PCs, into education to improve learning outcomes in South African government schools. Furthermore, because of the coronavirus pandemic that started in 2020, educators were increasingly expected to find alternative, digital, online methods to continue teaching learners. Thus, the need for remote or distance education suddenly became an important factor in creating a need for online, remote learning. Against this backdrop this study aimed to determine how and in what ways educators could be supported to promote effective use of Tablet PCs both in the classroom and for distance learning. This study used Action Design Research to develop a guide based on both theory and the results gathered from the educator participants at a local secondary government school in Makhanda, South Africa. The finalised guide presents recommendations to educators, principals, and the DBE to promote acceptance and adoption of technology in the classroom and for distance learning. These recommendations include the provision of data, technological training and pedagogical support, a functioning community of practice, an online learning community of practice, and support from the DBE. Other enrichment factors were also recommended. , Thesis (MCom) -- Faculty of Commerce, Information Systems, 2021
- Full Text:
- Date Issued: 2021-10-29
Capital flows and real exchange rate movement in South Africa
- Authors: Lindani, Sandiswa
- Date: 2021-09
- Subjects: Foreign exchange rates , Exchange rate pass-through , Capital movements
- Language: English
- Type: Master's/ theses , text
- Identifier: http://hdl.handle.net/10353/20417 , vital:45664
- Description: The neoclassical theory suggests that free flow of external capital should be equilibrating and thereby facilitating smoothening of an economy's consumption or production patterns. Based on this background, this study empirically examines the extent to which the different forms of capital flows amongst other variables influence the real exchange rate in South Africa for the period 1980 to 2019, using annual data. Estimation techniques employed include the Johansen Co-integration Approach and the Vector error correction model (VECM). The variables were found to be co-integrated, with six co-integrating vectors existing. The long-run results revealed that FPI has an appreciating effect on the exchange rate in South Africa. Based on the results, policy recommendations are suggested. , Thesis (MCom) (Economics) -- University of Fort Hare, 2021.
- Full Text:
- Date Issued: 2021-09
- Authors: Lindani, Sandiswa
- Date: 2021-09
- Subjects: Foreign exchange rates , Exchange rate pass-through , Capital movements
- Language: English
- Type: Master's/ theses , text
- Identifier: http://hdl.handle.net/10353/20417 , vital:45664
- Description: The neoclassical theory suggests that free flow of external capital should be equilibrating and thereby facilitating smoothening of an economy's consumption or production patterns. Based on this background, this study empirically examines the extent to which the different forms of capital flows amongst other variables influence the real exchange rate in South Africa for the period 1980 to 2019, using annual data. Estimation techniques employed include the Johansen Co-integration Approach and the Vector error correction model (VECM). The variables were found to be co-integrated, with six co-integrating vectors existing. The long-run results revealed that FPI has an appreciating effect on the exchange rate in South Africa. Based on the results, policy recommendations are suggested. , Thesis (MCom) (Economics) -- University of Fort Hare, 2021.
- Full Text:
- Date Issued: 2021-09
Effect of grazing systems and age on enteric methane production and performance plus grazing system effect on ruminal fermentation parameters of Nguni and Bonsmara beef cows
- Authors: Kayima, Denis
- Date: 2021-09
- Subjects: Grazing , Pastures--Management , Ruminants--Feeding and feeds
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20583 , vital:46153
- Description: Beef breeds of cattle are predominantly raised through extensive grazing and produce the highest levels of enteric methane (CH4) through ruminal fermentation. The objective of this study was to evaluate the effect of breed, grazing, and age on enteric methane production and performance of beef cows as well as effect of breed and grazing system on ruminal fermentation parameters. Two separate studies were conducted; the first study evaluated the effect of grazing system, breed, and age on ruminal enteric methane production and performance of selected beef breeds. The second study evaluated the effect of the grazing system and breed on ruminal fermentation. In the first study, two breeds (Nguni and Bonsmara) raised under two grazing systems (communal and commercial) in a random complete block design were grouped into 3 age categories. Eighty-four cows aged between 24-120 months were randomly selected and grouped by age: group A (young adult cow, n = 7, 24-48 months old), group B (adult, n = 7, 60-80 months old), and group C (old adult, n = 7, 90-120 months) in either grazing system. Data were collected on methane production per day, body condition, and weight used to estimate dry matter intake (DMI), methane per DMI, and methane per body weight. In the second study, 40 cows of the same age group, parity, and physiological status were used. Ten cows per breed (Bonsmara and Nguni) in either grazing system (communal and commercial) were used in a random complete block design. Rumen fluid collection was done by the stomach tube method. Data were collected on ruminal ammonia-nitrogen (NH3-N), pH, Temperature, volatile fatty acids (VFAs). Older animals produced higher methane per head in the order of C > B > A; (P<0.0001). Performance parameters like Body condition score (BCS), body weight (BW), dry matter intake (DMI), and daily methane were higher (P<0.05) in Bonsmara. However, Methane per BW was higher in Nguni (P<0.05), and methane per DMI did not differ among breeds (P>0.05). Body condition, BW, and DMI were higher (P<0.05) in commercial grazing system. Contrary, daily methane production, methane production per DMI, and methane produced per BW were higher in communal grazing. In the second study, Ruminal NH3-N concentration ranged between 69.05 - 96.78 mg/L and was higher (P<0.05) in Nguni. It was also higher (P<0.05) in the commercial grazing system. Ruminal pH, temperature, total VFAs, and certain individual VFAs (iso-butyrate, valeric and iso-valeric) did not differ (P>0.05) among breeds and grazing systems. However, total VFAs were slightly lower in communal grazing (78.87 mmol/L) than commercial grazing (89.80 mmol/L). Acetate, propionate, butyrate proportions, and acetate to propionate ratio did not differ (P>0.05) among breeds but differed (P<0.05) between grazing systems. Acetate (P<0.05) and acetate to propionate ratio (P<0.05) were higher in the communal grazing system, while the reverse was true for propionate (P<0.05) and butyrate (P<0.05). Bonsmara produced more methane than Nguni under similar conditions, with Nguni uniquely producing more methane per BW, indicating host genetics influence. Communal animals and older animals produced more CH4 than commercial and younger cows regardless of the breed, indicating ruminal inefficiencies in very old cows. These results emphasize the idea that host genetics or breed, grazing system, and age influence methane output and performance. Hence, breeding strategies for hard-to-measure traits like methane production need to put all these factors into consideration. , Thesis (MSc) (Animal Science) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-09
- Authors: Kayima, Denis
- Date: 2021-09
- Subjects: Grazing , Pastures--Management , Ruminants--Feeding and feeds
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/20583 , vital:46153
- Description: Beef breeds of cattle are predominantly raised through extensive grazing and produce the highest levels of enteric methane (CH4) through ruminal fermentation. The objective of this study was to evaluate the effect of breed, grazing, and age on enteric methane production and performance of beef cows as well as effect of breed and grazing system on ruminal fermentation parameters. Two separate studies were conducted; the first study evaluated the effect of grazing system, breed, and age on ruminal enteric methane production and performance of selected beef breeds. The second study evaluated the effect of the grazing system and breed on ruminal fermentation. In the first study, two breeds (Nguni and Bonsmara) raised under two grazing systems (communal and commercial) in a random complete block design were grouped into 3 age categories. Eighty-four cows aged between 24-120 months were randomly selected and grouped by age: group A (young adult cow, n = 7, 24-48 months old), group B (adult, n = 7, 60-80 months old), and group C (old adult, n = 7, 90-120 months) in either grazing system. Data were collected on methane production per day, body condition, and weight used to estimate dry matter intake (DMI), methane per DMI, and methane per body weight. In the second study, 40 cows of the same age group, parity, and physiological status were used. Ten cows per breed (Bonsmara and Nguni) in either grazing system (communal and commercial) were used in a random complete block design. Rumen fluid collection was done by the stomach tube method. Data were collected on ruminal ammonia-nitrogen (NH3-N), pH, Temperature, volatile fatty acids (VFAs). Older animals produced higher methane per head in the order of C > B > A; (P<0.0001). Performance parameters like Body condition score (BCS), body weight (BW), dry matter intake (DMI), and daily methane were higher (P<0.05) in Bonsmara. However, Methane per BW was higher in Nguni (P<0.05), and methane per DMI did not differ among breeds (P>0.05). Body condition, BW, and DMI were higher (P<0.05) in commercial grazing system. Contrary, daily methane production, methane production per DMI, and methane produced per BW were higher in communal grazing. In the second study, Ruminal NH3-N concentration ranged between 69.05 - 96.78 mg/L and was higher (P<0.05) in Nguni. It was also higher (P<0.05) in the commercial grazing system. Ruminal pH, temperature, total VFAs, and certain individual VFAs (iso-butyrate, valeric and iso-valeric) did not differ (P>0.05) among breeds and grazing systems. However, total VFAs were slightly lower in communal grazing (78.87 mmol/L) than commercial grazing (89.80 mmol/L). Acetate, propionate, butyrate proportions, and acetate to propionate ratio did not differ (P>0.05) among breeds but differed (P<0.05) between grazing systems. Acetate (P<0.05) and acetate to propionate ratio (P<0.05) were higher in the communal grazing system, while the reverse was true for propionate (P<0.05) and butyrate (P<0.05). Bonsmara produced more methane than Nguni under similar conditions, with Nguni uniquely producing more methane per BW, indicating host genetics influence. Communal animals and older animals produced more CH4 than commercial and younger cows regardless of the breed, indicating ruminal inefficiencies in very old cows. These results emphasize the idea that host genetics or breed, grazing system, and age influence methane output and performance. Hence, breeding strategies for hard-to-measure traits like methane production need to put all these factors into consideration. , Thesis (MSc) (Animal Science) -- University of Fort Hare, 2021
- Full Text:
- Date Issued: 2021-09
An investigation into the effects of nano-carbons on the negative electrode morphology of lead acid batteries under high rate partial state of capacity cycling
- Authors: Bolo, Lukanyo
- Date: 2021-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53324 , vital:45132
- Description: New technological developments in the field of Hybrid Electric Vehicles (HEV’s), vehicle stop-start applications and electrical power utility devices have brought about new demands on the use of energy storage devices such as the Pb-acid battery. These applications require a new understanding and research into the material chemistry of the battery where it has to functionin a Partial State of Capacity Cycling (PSoCC) or High Rate Partial State of Capacity Cycling (HRPSoCC)duty. The Pb-acid battery is well known for its use in the automotive industry where it had worked for decades as a typical Starter, Lighting and Ignition (SLI) power source. However, the conventional Pb-acid battery is not suitable for the new types of vehicle demands and applications. When the Pb-lead acid battery is subjected to PSoCC conditions, very quickly excessive amount of non-conducting PbSO4crystals are formed on the negative plates of the battery that then drastically reduce its useful life in application. Over the years, researchers have shown that the small addition of certain carbon types to the negative plate active material (NAM) during battery manufacturing can reduce the sulfation effect thereby increasing its use the modern vehicle applications. This study investigated industrial manufactured cells that contained up to 0.5 % by weight two types of carbons in the NAM. These were compared to standard built cells in terms of their standard achievable capacities at various rates, their Cold Cranking Ability (CCA), their Dynamic Charge Acceptance (DCA) and a simplified PSoCC test. The carbons were classified as an activated carbon and a carbon nano-fiber and were included as a dry weight additive during the standard paste manufacturing process of the negative plate. Cells were built with a 9-plate configuration using standard expanded grid positive plates with a nominal rated capacity of 36 Ah. The cells were formed and subjected to a number of electrochemical tests, of which selected negative plates were then studied using Scanning Electron Microscopy (SEM) and Electrochemical in-situ Atomic Force Microscopy (EC-AFM). The microscopic study was then used to try and relate the observed material characteristics of the NAM with the carbons to the electrochemical results observed when testing a built cell. , Thesis (MA) --Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-04
- Authors: Bolo, Lukanyo
- Date: 2021-04
- Subjects: Port Elizabeth (South Africa) , Eastern Cape (South Africa) , South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10948/53324 , vital:45132
- Description: New technological developments in the field of Hybrid Electric Vehicles (HEV’s), vehicle stop-start applications and electrical power utility devices have brought about new demands on the use of energy storage devices such as the Pb-acid battery. These applications require a new understanding and research into the material chemistry of the battery where it has to functionin a Partial State of Capacity Cycling (PSoCC) or High Rate Partial State of Capacity Cycling (HRPSoCC)duty. The Pb-acid battery is well known for its use in the automotive industry where it had worked for decades as a typical Starter, Lighting and Ignition (SLI) power source. However, the conventional Pb-acid battery is not suitable for the new types of vehicle demands and applications. When the Pb-lead acid battery is subjected to PSoCC conditions, very quickly excessive amount of non-conducting PbSO4crystals are formed on the negative plates of the battery that then drastically reduce its useful life in application. Over the years, researchers have shown that the small addition of certain carbon types to the negative plate active material (NAM) during battery manufacturing can reduce the sulfation effect thereby increasing its use the modern vehicle applications. This study investigated industrial manufactured cells that contained up to 0.5 % by weight two types of carbons in the NAM. These were compared to standard built cells in terms of their standard achievable capacities at various rates, their Cold Cranking Ability (CCA), their Dynamic Charge Acceptance (DCA) and a simplified PSoCC test. The carbons were classified as an activated carbon and a carbon nano-fiber and were included as a dry weight additive during the standard paste manufacturing process of the negative plate. Cells were built with a 9-plate configuration using standard expanded grid positive plates with a nominal rated capacity of 36 Ah. The cells were formed and subjected to a number of electrochemical tests, of which selected negative plates were then studied using Scanning Electron Microscopy (SEM) and Electrochemical in-situ Atomic Force Microscopy (EC-AFM). The microscopic study was then used to try and relate the observed material characteristics of the NAM with the carbons to the electrochemical results observed when testing a built cell. , Thesis (MA) --Faculty of Science, School of Biomolecular and Chemical Sciences, 2021
- Full Text:
- Date Issued: 2021-04
Educators ‘Perceptions of The Implementation of The National Curriculum Statement in Mt Fletcher District of The Eastern Cape Province
- Authors: Sikhunyana, Philiswa
- Date: 2013
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/2957 , vital:43114
- Description: The National Department of Education has undergone drastically changes from 1994. This study is about teacher‘s perceptions of the implementation of NCS. This study seeks to reveal the perception, feelings and the beliefs of teachers towards the implementation of the New Curriculum Statement in Mount Fletcher District of Eastern Cape Province. A mixed mode approach was conducted in this study in a form of quantitative and qualitative methods. Stratified random sampling (schools) and purposive sampling was used to draw the participants (teachers) from different High schools in Mt Fletcher. Data was analyzed following this pattern of organizing, transcribing, coding, establishing themes or categories, structuring, findings which paved way for the recommendations of this study and conclusion. The findings of this study reveals that teachers are just shooting in the dark in the sense that few teachers are implementing NCS successfully using their own methods and strategies of teaching and learning with a very limited clear understanding of the policy documents related to NCS principles while most schools and teachers are implementing through trial and error method, policy documents are just ―blue print to them as they received no clarity of them. And above all, teachers are lamenting on systematic, pedagogical and societal challenges that hindering the process of thorough implementation of NCS. Based on the findings the researcher recommends that the National Department of Education must pay attention for the Systemic challenges e.g. thorough training of teachers on methods of teaching and learning so that they can be able to understand the policies and methods of teaching and learning. She also recommends that whenever the NDoE is introducing new reforms on education, advocacy and awareness must reach the level of implementers not the understanding of the delegates. The NDoE again must pay attention to overcrowded classrooms and classes that are not conducive for teaching and learning (poor infrastructure), lack of basic and appropriate learning materials; Societal challenges e.g. Lack of parental support and Pedagogical challenges e.g. inappropriate teaching methods as well as learning and teacher support material, unqualified and under-qualified teachers, inappropriate assessment procedures, lack of support for teachers. Key words: National Curriculum statement; Teachers; Department of Education; Implementation and Perception. , Thesis (MMED) -- Faculty of Educational Sciences, 2013
- Full Text:
- Date Issued: 2013
- Authors: Sikhunyana, Philiswa
- Date: 2013
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/2957 , vital:43114
- Description: The National Department of Education has undergone drastically changes from 1994. This study is about teacher‘s perceptions of the implementation of NCS. This study seeks to reveal the perception, feelings and the beliefs of teachers towards the implementation of the New Curriculum Statement in Mount Fletcher District of Eastern Cape Province. A mixed mode approach was conducted in this study in a form of quantitative and qualitative methods. Stratified random sampling (schools) and purposive sampling was used to draw the participants (teachers) from different High schools in Mt Fletcher. Data was analyzed following this pattern of organizing, transcribing, coding, establishing themes or categories, structuring, findings which paved way for the recommendations of this study and conclusion. The findings of this study reveals that teachers are just shooting in the dark in the sense that few teachers are implementing NCS successfully using their own methods and strategies of teaching and learning with a very limited clear understanding of the policy documents related to NCS principles while most schools and teachers are implementing through trial and error method, policy documents are just ―blue print to them as they received no clarity of them. And above all, teachers are lamenting on systematic, pedagogical and societal challenges that hindering the process of thorough implementation of NCS. Based on the findings the researcher recommends that the National Department of Education must pay attention for the Systemic challenges e.g. thorough training of teachers on methods of teaching and learning so that they can be able to understand the policies and methods of teaching and learning. She also recommends that whenever the NDoE is introducing new reforms on education, advocacy and awareness must reach the level of implementers not the understanding of the delegates. The NDoE again must pay attention to overcrowded classrooms and classes that are not conducive for teaching and learning (poor infrastructure), lack of basic and appropriate learning materials; Societal challenges e.g. Lack of parental support and Pedagogical challenges e.g. inappropriate teaching methods as well as learning and teacher support material, unqualified and under-qualified teachers, inappropriate assessment procedures, lack of support for teachers. Key words: National Curriculum statement; Teachers; Department of Education; Implementation and Perception. , Thesis (MMED) -- Faculty of Educational Sciences, 2013
- Full Text:
- Date Issued: 2013
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