Assessment of rangeland condition and evaluation of farmers' perception in Njwaxa and Mbizana communal rangelands of the Eastern Cape, South Africa
- Authors: Ngcofe, Odwa Armstrong
- Date: 2016
- Subjects: Rangelands -- South Africa -- Eastern Cape Land tenure -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13259 , vital:39627
- Description: This study was conducted to determine of rangeland condition in terms of botanical composition, soil nutrient composition, and also to evaluate farmers’ perception on rangeland condition and degradation in two communal villages Njwaxa and Mbizana in the Eastern Cape Province of South Africa in 2014. A Structured questionnaire consisting of close and open-ended questions was used to investigate farmers’ perceptions on range condition, land degradation, and their causes. Fifty households with livestock were randomly selected in two communal areas of Middledrift (i.e. Njwaxa and Mbizana). Respondents of 21 years and above were selected. For assessment of range condition three homogeneous vegetation units (HVU) were demarcated in all study sites, namely slope; valley and toplands were demarcated and sub-divided into four 100m x 50m replicates. In each replicate, four 100m transects were laid parallel to each other 25m apart 1m2 quadrant was systematically located four times along each transect for herbaceous vegetation and soil sampling. The step point method was employed to determine herbaceous species composition and basal cover. A 400m2 belt transect was used to determine woody vegetation composition, density and tree equivalents in each HVU. The germination method was employed for soil seed bank composition and plant density. The soil micro and macro nutrients (N, P, K OC, Ca, Mg, Zn, Cu and Mn) and pH were also analyzed The majority of the respondents were between the ages of 51-60 years. Most of the farmers had more cattle (38percent) than goats (32percent) and sheep (30percent). Livestock numbers were perceived to have declined over the previous 20 years by the majority of respondents (96percent). The respondents indicated that their rangelands were mainly used for browsing (1.37), fire wood (2.01), building and fencing (2.63) and medical purposes (3.66). All the respondents indicated that their rangelands were highly degraded. Sheet erosion (50percent) was perceived to be the major type of soil erosion indicator mentioned by the farmers, followed by gully erosion (29percent) and rill erosion (21percent). The rangeland was dominated by Increaser II (pioneer) (63.2 percent) grass species followed by Decreaser (mesophytes) species (26.3percent). Digitaria eriantha in the valley (53.5 percent) was significantly higher (p<0.05) than both in the top (10.5percent) and sloppy areas (33.5percent) at Njwaxa communal rangeland, the abundance of D. eriantha was significantly higher (p<0.05) than top and valley in Mbizana communal rangeland. The results showed that soil seed banks were dominated by perennials, followed by annuals and biennial species being least abundant. The dominant forb Jamebrittenia c.f. albanesis was significantly higher (p<0.05) in both slopes (6.65percent) and toplands (7.34percent) than in the valley (3.15). The second most dominant species Puesdognaphalium undulata was significantly higher (p<0.05) in topland areas (6percent) than in valley bottom (3.8percent) and sloppy areas (4.3percent). The results of soil nutrients revealed no significant differences (p>0.05) in the concentration of OC, Ca, and Mg between the communities and seasons. Phosphorus (P) was significantly higher (p<0.05) in winter (concentrations) in most of the sites, except the top sites of Mbizana where summer concentration of P was significantly higher than winter. Potassium (K) was significantly higher (p<0.05) in summer than in winter in most of the HVUs, except the topland areas of Njwaxa and Mbizana sloppy areas where there were no significant differences (p>0.05) in the concentration of K. Soil pH did not display any significant differences (p>0.05) between communities and sites. The mean soil pH recorded in this study was 5.4 implying the soils of Njwaxa and Mbizana communities were acidic. It is evident that communal farmers are well aware of their rangeland condition, changes occurring in their rangelands, their causes and are capable of suggesting some solutions in controlling the declining condition of the rangelands. This study has shown the importance of engaging farmers’ inputs in range assessment since those are people bearing the consequences of rangeland degradation.
- Full Text:
- Authors: Ngcofe, Odwa Armstrong
- Date: 2016
- Subjects: Rangelands -- South Africa -- Eastern Cape Land tenure -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13259 , vital:39627
- Description: This study was conducted to determine of rangeland condition in terms of botanical composition, soil nutrient composition, and also to evaluate farmers’ perception on rangeland condition and degradation in two communal villages Njwaxa and Mbizana in the Eastern Cape Province of South Africa in 2014. A Structured questionnaire consisting of close and open-ended questions was used to investigate farmers’ perceptions on range condition, land degradation, and their causes. Fifty households with livestock were randomly selected in two communal areas of Middledrift (i.e. Njwaxa and Mbizana). Respondents of 21 years and above were selected. For assessment of range condition three homogeneous vegetation units (HVU) were demarcated in all study sites, namely slope; valley and toplands were demarcated and sub-divided into four 100m x 50m replicates. In each replicate, four 100m transects were laid parallel to each other 25m apart 1m2 quadrant was systematically located four times along each transect for herbaceous vegetation and soil sampling. The step point method was employed to determine herbaceous species composition and basal cover. A 400m2 belt transect was used to determine woody vegetation composition, density and tree equivalents in each HVU. The germination method was employed for soil seed bank composition and plant density. The soil micro and macro nutrients (N, P, K OC, Ca, Mg, Zn, Cu and Mn) and pH were also analyzed The majority of the respondents were between the ages of 51-60 years. Most of the farmers had more cattle (38percent) than goats (32percent) and sheep (30percent). Livestock numbers were perceived to have declined over the previous 20 years by the majority of respondents (96percent). The respondents indicated that their rangelands were mainly used for browsing (1.37), fire wood (2.01), building and fencing (2.63) and medical purposes (3.66). All the respondents indicated that their rangelands were highly degraded. Sheet erosion (50percent) was perceived to be the major type of soil erosion indicator mentioned by the farmers, followed by gully erosion (29percent) and rill erosion (21percent). The rangeland was dominated by Increaser II (pioneer) (63.2 percent) grass species followed by Decreaser (mesophytes) species (26.3percent). Digitaria eriantha in the valley (53.5 percent) was significantly higher (p<0.05) than both in the top (10.5percent) and sloppy areas (33.5percent) at Njwaxa communal rangeland, the abundance of D. eriantha was significantly higher (p<0.05) than top and valley in Mbizana communal rangeland. The results showed that soil seed banks were dominated by perennials, followed by annuals and biennial species being least abundant. The dominant forb Jamebrittenia c.f. albanesis was significantly higher (p<0.05) in both slopes (6.65percent) and toplands (7.34percent) than in the valley (3.15). The second most dominant species Puesdognaphalium undulata was significantly higher (p<0.05) in topland areas (6percent) than in valley bottom (3.8percent) and sloppy areas (4.3percent). The results of soil nutrients revealed no significant differences (p>0.05) in the concentration of OC, Ca, and Mg between the communities and seasons. Phosphorus (P) was significantly higher (p<0.05) in winter (concentrations) in most of the sites, except the top sites of Mbizana where summer concentration of P was significantly higher than winter. Potassium (K) was significantly higher (p<0.05) in summer than in winter in most of the HVUs, except the topland areas of Njwaxa and Mbizana sloppy areas where there were no significant differences (p>0.05) in the concentration of K. Soil pH did not display any significant differences (p>0.05) between communities and sites. The mean soil pH recorded in this study was 5.4 implying the soils of Njwaxa and Mbizana communities were acidic. It is evident that communal farmers are well aware of their rangeland condition, changes occurring in their rangelands, their causes and are capable of suggesting some solutions in controlling the declining condition of the rangelands. This study has shown the importance of engaging farmers’ inputs in range assessment since those are people bearing the consequences of rangeland degradation.
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Assessment of the flocculating efficiency of bioflocculant produced by bacillus sp. Aemreg4 isolated from Tyhume river, Eastern Cape, South Africa
- Authors: Ntsangani, Nozipho
- Date: 2016
- Subjects: Flocculants
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11357 , http://hdl.handle.net/10353/d1021324
- Description: Bioflocculants are flocculating substances produced by microorganisms during growth and have recently received considerable attention from researchers; due to their biodegradability, non-toxicity and lack of secondary pollution from degradation intermediates. This study evaluated the efficiency of bioflocculant produced by Bacillus sp. AEMREG4 isolated from Tyhume River. The bacterial identification was through 16S rDNA sequencing; nucleotide sequences were deposited in GenBank as Bacillus sp. AEMREG4 with an Accession number KP406729. The optimum culture conditions for bioflocculant production were an inoculum size of 4% (v/v) and starch as well as yeast extract as sole carbon and nitrogen sources respectively. The addition of CaCl2 enhanced the flocculating activity, at a wide range of pH 4-10 and the highest flocculating activity was reached at an initial pH 8 (80%). A bioflocculant yield of 0.78 g was recovered from 1 L of culture broth. The optimum flocculating activity of 78% was reached at the lowest bioflocculant dosage of 0.1 mg/ml and the presence of divalent cations (Ca2+, Mn2+ and Mg2+) as well as a trivalent cation (Al3+) enhanced flocculating activity. The purified bioflocculant retained more than 70% flocculating activity when subjected to heating at 100 °C for 1 h and maximum flocculating activity of 83% was achieved at both acidic and basic pH values of 3 and 10 respectively. Chemical analysis showed that the bioflocculant is predominantly polysaccharide. The Fourier transform infrared (FTIR) spectrum revealed the presence of carboxyl, hydroxyl and methoxyl groups as the functional moieties and the scanning electron microscopy (SEM) imaging of the purified bioflocculant showed its morphological structure as rod-shaped which contributes to its high flocculating efficiency. The high flocculation activity displayed by this bioflocculant indicates its potential suitability for industrial application.Keywords: Bioflocculant, Bacillus sp. AEMREG4, flocculating activity.
- Full Text:
- Authors: Ntsangani, Nozipho
- Date: 2016
- Subjects: Flocculants
- Language: English
- Type: Thesis , Masters , MSc (Biochemistry)
- Identifier: vital:11357 , http://hdl.handle.net/10353/d1021324
- Description: Bioflocculants are flocculating substances produced by microorganisms during growth and have recently received considerable attention from researchers; due to their biodegradability, non-toxicity and lack of secondary pollution from degradation intermediates. This study evaluated the efficiency of bioflocculant produced by Bacillus sp. AEMREG4 isolated from Tyhume River. The bacterial identification was through 16S rDNA sequencing; nucleotide sequences were deposited in GenBank as Bacillus sp. AEMREG4 with an Accession number KP406729. The optimum culture conditions for bioflocculant production were an inoculum size of 4% (v/v) and starch as well as yeast extract as sole carbon and nitrogen sources respectively. The addition of CaCl2 enhanced the flocculating activity, at a wide range of pH 4-10 and the highest flocculating activity was reached at an initial pH 8 (80%). A bioflocculant yield of 0.78 g was recovered from 1 L of culture broth. The optimum flocculating activity of 78% was reached at the lowest bioflocculant dosage of 0.1 mg/ml and the presence of divalent cations (Ca2+, Mn2+ and Mg2+) as well as a trivalent cation (Al3+) enhanced flocculating activity. The purified bioflocculant retained more than 70% flocculating activity when subjected to heating at 100 °C for 1 h and maximum flocculating activity of 83% was achieved at both acidic and basic pH values of 3 and 10 respectively. Chemical analysis showed that the bioflocculant is predominantly polysaccharide. The Fourier transform infrared (FTIR) spectrum revealed the presence of carboxyl, hydroxyl and methoxyl groups as the functional moieties and the scanning electron microscopy (SEM) imaging of the purified bioflocculant showed its morphological structure as rod-shaped which contributes to its high flocculating efficiency. The high flocculation activity displayed by this bioflocculant indicates its potential suitability for industrial application.Keywords: Bioflocculant, Bacillus sp. AEMREG4, flocculating activity.
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Between"culture" and "Cruelty"narratives of widows on land dispossession in Gqadu administrative area, Mbashe Municipality , Eastern Cape
- Authors: Baleka, Zola
- Date: 2016
- Subjects: Widows -- South Africa -- Eastern Cape Land tenure -- South Africa -- Eastern Cape Right of property -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/5083 , vital:29057
- Description: This study highlights the cultural underpinnings of specific indulgences pertaining to land ownership with reference to widowhood in the rural Eastern Cape. The study does this by examining the narratives of widows about their experiences of land dispossession in Nqadu Administrative Area. Nqadu Administrative Area is a rural community in Mbhashe Local Municipality in the Eastern Cape Province of South Africa. The study focuses on widows’ experiences relating to the cultural practices of the community regarding land ownership. A qualitative, case study design was adopted. To uncover the widows’ narratives, the study utilised in-depth interviews and focus group discussions, with a sample of 50 widows. Further empirical data were obtained from four members of the municipal Land Committees, two Ward Councillors, four Traditional Leaders and two officials from the Eastern Cape Department of Rural Development and Agrarian Reform, using in-depth and key informant interviews. The study found that widows were vulnerable to land ownership violations and dispossessions, and that these violations were perpetrated by community members, particularly relatives of deceased husbands. Low levels of education and fear of antagonising clan relatives played a vital role in preventing widows from fighting for their legal rights. The failure of widows to fight for their rights increased their chances of being heavily exposed to dispossession of their land rights. Cultural practices within the communities catalysed abusive practices against widows, particularly against those whose marriage was not ‘recognised’ due to various stated reasons. The study also revealed that widows who had married as second wives and those who did not bear children experienced egregious abuses. Another finding was that men from Nqadu Administrative Area were given priority during the allocation of land, based on cultural and traditional practices, and were given land of their own choice depending on availability. The study thus highlights the impact of cultural practices and the ways in which these became instruments of gender abuse, despite the existence of laws designed to prevent specific social cruelties.
- Full Text:
- Authors: Baleka, Zola
- Date: 2016
- Subjects: Widows -- South Africa -- Eastern Cape Land tenure -- South Africa -- Eastern Cape Right of property -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , Degree
- Identifier: http://hdl.handle.net/10353/5083 , vital:29057
- Description: This study highlights the cultural underpinnings of specific indulgences pertaining to land ownership with reference to widowhood in the rural Eastern Cape. The study does this by examining the narratives of widows about their experiences of land dispossession in Nqadu Administrative Area. Nqadu Administrative Area is a rural community in Mbhashe Local Municipality in the Eastern Cape Province of South Africa. The study focuses on widows’ experiences relating to the cultural practices of the community regarding land ownership. A qualitative, case study design was adopted. To uncover the widows’ narratives, the study utilised in-depth interviews and focus group discussions, with a sample of 50 widows. Further empirical data were obtained from four members of the municipal Land Committees, two Ward Councillors, four Traditional Leaders and two officials from the Eastern Cape Department of Rural Development and Agrarian Reform, using in-depth and key informant interviews. The study found that widows were vulnerable to land ownership violations and dispossessions, and that these violations were perpetrated by community members, particularly relatives of deceased husbands. Low levels of education and fear of antagonising clan relatives played a vital role in preventing widows from fighting for their legal rights. The failure of widows to fight for their rights increased their chances of being heavily exposed to dispossession of their land rights. Cultural practices within the communities catalysed abusive practices against widows, particularly against those whose marriage was not ‘recognised’ due to various stated reasons. The study also revealed that widows who had married as second wives and those who did not bear children experienced egregious abuses. Another finding was that men from Nqadu Administrative Area were given priority during the allocation of land, based on cultural and traditional practices, and were given land of their own choice depending on availability. The study thus highlights the impact of cultural practices and the ways in which these became instruments of gender abuse, despite the existence of laws designed to prevent specific social cruelties.
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Change management in local government : a case study of Buffalo City Metropolitan Municipality (2009-2011)
- Authors: Kwakweni, A
- Date: 2016
- Subjects: Local government -- South Africa -- Eastern Cape Organizational change -- South Africa -- Management
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2216 , vital:27707
- Description: The main objective of this study was to explore how change can be understood fromthe change management perspective, especially in the local sphere of government. The study looked specifically at the Buffalo City Metropolitan Municipality journey through a significant shift or transition from a category B to Category A municipality during the 2011 Local Government elections. Based on change theory and a selected change management model, the framework for change management and issues related to it were constructed. Additionally, a synthesis of the most important phases and interventions in a strategic change process or project was created. The phases included: starting point, planning, implementation and evaluation, and securing. Various literature sources were consulted during the study. Inter alia, these included Lewin’s change management model, which states that change has to follow three stages—including, unfreezing, moving and refreezing. All these stages by Lewin(1951) emphasise the critical management role in driving planned or proactive change in order to address the likely emergence of resistance by observing a systematic process. A qualitative approach was utilized in order to solicit in-depth information using a structured questionnaire. Respondents were visited by the researcher in their offices, to gather data. To this effect, a total 25 respondents from the top management, councillors and middle management were sampled and interviewed accordingly. According to the findings of this study, important change management phases were recognized through researching theoretical literature—starting, planning and implementation phases. Empirical information at the starting phase involves analysis of the current and desired states and the need for change accompanied by guiding coalitions. In the planning phase, the most important interventions is project formulation, action plan development, analysis of prior and current strategic change initiatives and organizational structure analysis. In the change implementation phase the interventions of importance are the launch, quick-wins, creation of a sense of urgency, management of change resistance and communication of the change.
- Full Text:
- Authors: Kwakweni, A
- Date: 2016
- Subjects: Local government -- South Africa -- Eastern Cape Organizational change -- South Africa -- Management
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2216 , vital:27707
- Description: The main objective of this study was to explore how change can be understood fromthe change management perspective, especially in the local sphere of government. The study looked specifically at the Buffalo City Metropolitan Municipality journey through a significant shift or transition from a category B to Category A municipality during the 2011 Local Government elections. Based on change theory and a selected change management model, the framework for change management and issues related to it were constructed. Additionally, a synthesis of the most important phases and interventions in a strategic change process or project was created. The phases included: starting point, planning, implementation and evaluation, and securing. Various literature sources were consulted during the study. Inter alia, these included Lewin’s change management model, which states that change has to follow three stages—including, unfreezing, moving and refreezing. All these stages by Lewin(1951) emphasise the critical management role in driving planned or proactive change in order to address the likely emergence of resistance by observing a systematic process. A qualitative approach was utilized in order to solicit in-depth information using a structured questionnaire. Respondents were visited by the researcher in their offices, to gather data. To this effect, a total 25 respondents from the top management, councillors and middle management were sampled and interviewed accordingly. According to the findings of this study, important change management phases were recognized through researching theoretical literature—starting, planning and implementation phases. Empirical information at the starting phase involves analysis of the current and desired states and the need for change accompanied by guiding coalitions. In the planning phase, the most important interventions is project formulation, action plan development, analysis of prior and current strategic change initiatives and organizational structure analysis. In the change implementation phase the interventions of importance are the launch, quick-wins, creation of a sense of urgency, management of change resistance and communication of the change.
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Characterisation of selected municipal organic waste for energy conversion through gasification
- Authors: Ngubelanga, Nolitha
- Date: 2016
- Subjects: Biomass gasification Sewage -- Purification Biomass energy Renewable energy sources
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11020 , vital:36682
- Description: Biomass gasification has become a study of great interest over the years and plant biomass with cellulose, hemicellulose, and lignin found to be an ideal resource for conversion into heat and power through thermochemical processes such as gasification. The inadequate supply of the energy in the country has become critical with the national energy provider struggling to meet the energy demands of the ever growing population of South Africa. The depletion of natural resources and the unstable prices as well as the cost of transporting the fuels together with the environmental effects of burning fossil fuels are contributing factors to the energy crisis. Alternative sources of energy that are locally available, sustainable, and environmentally friendly are presently in demand as municipal organic wastes has been considered a source of renewable energy with gasification deemed one of the leading edge technologies to harness the energy. This research only studied the characteristics and kinetics of selected municipal organic waste including decaying wood, tomatoes, onions, cabbage, butternut and bones. The research did not involve the gasification process because of expenses associated with gasification processes, however, this has been considered as future studies under the conditions of available resources to carry out the actual gasification experiments. The characteristics of selected municipal organic wastes for energy conversion through gasification were actually investigated in this study and the implication of the value of each property interpreted in relation to gasification with specific reference to information available in the literature. Proximate analysis conducted on the wastes indicate that the physical properties in terms of the weight percentages of moisture, volatile matter fixed carbon and ash contents of the wastes vary considerably, especially with regards to the last three properties. The reason for this wide variation was attributed to the source of the wastes and the standard of living of the people vi in the area where the wastes were collected. However, the values obtained for these properties are within limits for the wastes to be adequately used as feedstocks in a gasification process, except for their content of ash, which was significantly high in all of the wastes for the aforementioned reasons. The ultimate analysis of the wastes as determined using the Energy Dispersive X-ray spectroscopy gave the percentage composition of the chemical elements present in the wastes, which suggest that carbon is the chief elemental constituent of the wastes. The highest carbon content of about 47% was recorded for bone due again to the reasons previously adduced. According to McKendry, 2002, the high carbon content of the wastes implies increased calorific value as well as increased gas production during gasification. A number of ash–forming elements were also found in the wastes, which included magnesium and potassium in low concentrations that does not pose any technical challenges during gasification, although their concentration may increase under high temperature gasification, which may equally result to some catalytic effect that would contribute to the overall gasification efficiency (Anukam et al., 2016). Calorific value analysis also suggests that the wastes contain reasonable amount of energy that can be converted to useful energy through gasification. Although, variation in calorific value was also noted, the highest calorific value of about 18 MJ/kg was recoded for bones, which correlates its data on the highest carbon content of all wastes. However, the data on the calorific value of the wastes suggests that the wastes are well suited for gasification by virtue of their calorific value. FTIR analysis revealed the major functional groups present in the internal structure of the wastes. The common functional groups observed were the OH group found in the band around 3600–3400cm-1 for most of the wastes; the C–H stretching band at 2970-2780 cm-1; and the C–O as well as the C–O–C observed in the region of 1740–1710 cm-1 and 1250-1220 cm-1 for all samples, respectively. Most functional group in the internal structures of gasification feedstocks function to facilitate faster vii rates of reaction and consequently faster rates of gasification that contributes to optimum efficiency under any conditions of gasification (Anukam et al., 2016). While thermogravimetric analysis established thermal parameters that are likely to have positive influence on the gasification of the wastes, kinetic investigation revealed two parameters that may also impact on the gasification of the wastes. These are activation energy and pre–exponential factor, which were found to be in good agreement with the values obtained in the literature even though variation in these parameters was noted. The values obtained for activation energy and pre–exponential factor using the Kissinger method of kinetic analysis showed a far less value for these two parameters when compared to commonly used feedstocks like wood and coal. This was a reason attributed to the chemical characteristics of the wastes, mainly their lower content of carbon compared to these two (wood and coal) commonly used fuels.
- Full Text:
- Authors: Ngubelanga, Nolitha
- Date: 2016
- Subjects: Biomass gasification Sewage -- Purification Biomass energy Renewable energy sources
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11020 , vital:36682
- Description: Biomass gasification has become a study of great interest over the years and plant biomass with cellulose, hemicellulose, and lignin found to be an ideal resource for conversion into heat and power through thermochemical processes such as gasification. The inadequate supply of the energy in the country has become critical with the national energy provider struggling to meet the energy demands of the ever growing population of South Africa. The depletion of natural resources and the unstable prices as well as the cost of transporting the fuels together with the environmental effects of burning fossil fuels are contributing factors to the energy crisis. Alternative sources of energy that are locally available, sustainable, and environmentally friendly are presently in demand as municipal organic wastes has been considered a source of renewable energy with gasification deemed one of the leading edge technologies to harness the energy. This research only studied the characteristics and kinetics of selected municipal organic waste including decaying wood, tomatoes, onions, cabbage, butternut and bones. The research did not involve the gasification process because of expenses associated with gasification processes, however, this has been considered as future studies under the conditions of available resources to carry out the actual gasification experiments. The characteristics of selected municipal organic wastes for energy conversion through gasification were actually investigated in this study and the implication of the value of each property interpreted in relation to gasification with specific reference to information available in the literature. Proximate analysis conducted on the wastes indicate that the physical properties in terms of the weight percentages of moisture, volatile matter fixed carbon and ash contents of the wastes vary considerably, especially with regards to the last three properties. The reason for this wide variation was attributed to the source of the wastes and the standard of living of the people vi in the area where the wastes were collected. However, the values obtained for these properties are within limits for the wastes to be adequately used as feedstocks in a gasification process, except for their content of ash, which was significantly high in all of the wastes for the aforementioned reasons. The ultimate analysis of the wastes as determined using the Energy Dispersive X-ray spectroscopy gave the percentage composition of the chemical elements present in the wastes, which suggest that carbon is the chief elemental constituent of the wastes. The highest carbon content of about 47% was recorded for bone due again to the reasons previously adduced. According to McKendry, 2002, the high carbon content of the wastes implies increased calorific value as well as increased gas production during gasification. A number of ash–forming elements were also found in the wastes, which included magnesium and potassium in low concentrations that does not pose any technical challenges during gasification, although their concentration may increase under high temperature gasification, which may equally result to some catalytic effect that would contribute to the overall gasification efficiency (Anukam et al., 2016). Calorific value analysis also suggests that the wastes contain reasonable amount of energy that can be converted to useful energy through gasification. Although, variation in calorific value was also noted, the highest calorific value of about 18 MJ/kg was recoded for bones, which correlates its data on the highest carbon content of all wastes. However, the data on the calorific value of the wastes suggests that the wastes are well suited for gasification by virtue of their calorific value. FTIR analysis revealed the major functional groups present in the internal structure of the wastes. The common functional groups observed were the OH group found in the band around 3600–3400cm-1 for most of the wastes; the C–H stretching band at 2970-2780 cm-1; and the C–O as well as the C–O–C observed in the region of 1740–1710 cm-1 and 1250-1220 cm-1 for all samples, respectively. Most functional group in the internal structures of gasification feedstocks function to facilitate faster vii rates of reaction and consequently faster rates of gasification that contributes to optimum efficiency under any conditions of gasification (Anukam et al., 2016). While thermogravimetric analysis established thermal parameters that are likely to have positive influence on the gasification of the wastes, kinetic investigation revealed two parameters that may also impact on the gasification of the wastes. These are activation energy and pre–exponential factor, which were found to be in good agreement with the values obtained in the literature even though variation in these parameters was noted. The values obtained for activation energy and pre–exponential factor using the Kissinger method of kinetic analysis showed a far less value for these two parameters when compared to commonly used feedstocks like wood and coal. This was a reason attributed to the chemical characteristics of the wastes, mainly their lower content of carbon compared to these two (wood and coal) commonly used fuels.
- Full Text:
Characterisation of the production and consumption of milk in the communal livestock production sector of the Eastern Cape Province, South Africa
- Authors: Kumbirai, Kaguru Tinashe
- Date: 2016
- Subjects: Milk consumption -- South Africa -- Eastern Cape Dairy farming -- Economic aspects -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/3066 , vital:28251
- Description: The study was conducted in Eastern Cape Province, South Africa with the objective of characterising milk production and consumption among the communal households. A pretested semi-structured questionnaire was used to collect data through a single visit survey between June 2014 and May 2015. The study was undertaken in five randomly selected communal districts using a multi – stage area probability sampling method. Household sample size was calculated using a statistical methodology through a fixed formula based on a rural population size of 4410000, at a confidence level of 95 percent. A total of 500 households were selected with a sample size of 20 households in 5 communities within five different communal districts within the province. Half of the total sample size was used to represent the number of non-milk producing households (250) to get a true reflection on consumption profiles for nonproducers. Across the province the average communal family size was between 5-10 members with a monthly income of ZAR1340 per household. On average, pasture land size of the sampled households was 1 ha, with a range of 0.25-1.7 ha. The numbers of animals per species found in the studied province was highest for sheep (310) followed by cattle (227) and goat (87). Average livestock holding per household in the study area was 9.85 TLU (Tropical Livestock Unit). According to the respondents the predominant milking livestock numbers were between 1-3 animals milking per household. In the studied area traditional hand milking of livestock was the major milking practices at 12 percent in goats, 15 percent in sheep and 45 percent in cattle milk production. Consumption was the predominant reason for milk production recorded at 27 percent across the province. Milk production was 43 percent most preferred in cattle followed by 32 percent in goat and least at 29 percent in sheep across the province. In general, from the study it was noted that the majority (38 percent) of the respondents across the province indicated 0-5mins as the time it took to milk most milk producing livestock. The majority of the milking practices was done (37 percent) predominantly once a day, followed by 2 percent twice daily across the province. The daily milk production was on average (0.45±1.07) 2-5 litre in cattle, (4.86±0.814) 0-1litre in goats and (2.62±0.42) 0-1 litre sheep per producing house hold with in the province The monthly raw milk consumption in the province was (2.20± 1.42) 2-5 litres of cattle milk, (4.78±0.79) 2-5 litres of goat milk and (4.98±0.69) 2-5 litres of sheep milk per consuming household.
- Full Text:
- Authors: Kumbirai, Kaguru Tinashe
- Date: 2016
- Subjects: Milk consumption -- South Africa -- Eastern Cape Dairy farming -- Economic aspects -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/3066 , vital:28251
- Description: The study was conducted in Eastern Cape Province, South Africa with the objective of characterising milk production and consumption among the communal households. A pretested semi-structured questionnaire was used to collect data through a single visit survey between June 2014 and May 2015. The study was undertaken in five randomly selected communal districts using a multi – stage area probability sampling method. Household sample size was calculated using a statistical methodology through a fixed formula based on a rural population size of 4410000, at a confidence level of 95 percent. A total of 500 households were selected with a sample size of 20 households in 5 communities within five different communal districts within the province. Half of the total sample size was used to represent the number of non-milk producing households (250) to get a true reflection on consumption profiles for nonproducers. Across the province the average communal family size was between 5-10 members with a monthly income of ZAR1340 per household. On average, pasture land size of the sampled households was 1 ha, with a range of 0.25-1.7 ha. The numbers of animals per species found in the studied province was highest for sheep (310) followed by cattle (227) and goat (87). Average livestock holding per household in the study area was 9.85 TLU (Tropical Livestock Unit). According to the respondents the predominant milking livestock numbers were between 1-3 animals milking per household. In the studied area traditional hand milking of livestock was the major milking practices at 12 percent in goats, 15 percent in sheep and 45 percent in cattle milk production. Consumption was the predominant reason for milk production recorded at 27 percent across the province. Milk production was 43 percent most preferred in cattle followed by 32 percent in goat and least at 29 percent in sheep across the province. In general, from the study it was noted that the majority (38 percent) of the respondents across the province indicated 0-5mins as the time it took to milk most milk producing livestock. The majority of the milking practices was done (37 percent) predominantly once a day, followed by 2 percent twice daily across the province. The daily milk production was on average (0.45±1.07) 2-5 litre in cattle, (4.86±0.814) 0-1litre in goats and (2.62±0.42) 0-1 litre sheep per producing house hold with in the province The monthly raw milk consumption in the province was (2.20± 1.42) 2-5 litres of cattle milk, (4.78±0.79) 2-5 litres of goat milk and (4.98±0.69) 2-5 litres of sheep milk per consuming household.
- Full Text:
Characterization of various garden grass species for energy conversion in a down draft biomass gasifier
- Authors: Mkosi, Lungisa
- Date: 2016
- Subjects: Biomass energy Greenhouse gases Renewable energy sources
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5817 , vital:29399
- Description: Energy plays a vital role in socio-economic development and raising living standards of human beings. The overreliance on fossil fuels results in the depletion of fossil fuels as well as environmental pollution from the green-house gases that result from the use of fossil fuels. Biomass feedstock are able to ameliorate this situation by utilizing the CO2 that has been used by plants during photosynthesis. This study investigated the suitability of the three garden grass species (Chloris gayana, Cynodon dactylon and Pennisetum clandestum) as biomass feedstock for gasification purposes. The three garden grass species were collected at the Alice Campus of the University of Fort Hare. These grass species were characterized using elemental analyser (CHNS), FT-IR, EDX and TGA. The Activation energy (Ea) of the three grass species were 48.22 kJ/mol for P. clandestum, 36.8 kJ/mol for C. gayana and 258 kJ/mol for C. dactylon. Of the three grass species, C. gayana had the lowest Activation energy of 36.8 kJ/mol and also had the highest maximum efficiency of 69 percent compared to 65.3 percent for P. clandestum and 63.5 percent for C. dactylon. Actual gasification was not carried out but the results on maximum efficiency were obtained from computer simulation of gasification.
- Full Text:
- Authors: Mkosi, Lungisa
- Date: 2016
- Subjects: Biomass energy Greenhouse gases Renewable energy sources
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/5817 , vital:29399
- Description: Energy plays a vital role in socio-economic development and raising living standards of human beings. The overreliance on fossil fuels results in the depletion of fossil fuels as well as environmental pollution from the green-house gases that result from the use of fossil fuels. Biomass feedstock are able to ameliorate this situation by utilizing the CO2 that has been used by plants during photosynthesis. This study investigated the suitability of the three garden grass species (Chloris gayana, Cynodon dactylon and Pennisetum clandestum) as biomass feedstock for gasification purposes. The three garden grass species were collected at the Alice Campus of the University of Fort Hare. These grass species were characterized using elemental analyser (CHNS), FT-IR, EDX and TGA. The Activation energy (Ea) of the three grass species were 48.22 kJ/mol for P. clandestum, 36.8 kJ/mol for C. gayana and 258 kJ/mol for C. dactylon. Of the three grass species, C. gayana had the lowest Activation energy of 36.8 kJ/mol and also had the highest maximum efficiency of 69 percent compared to 65.3 percent for P. clandestum and 63.5 percent for C. dactylon. Actual gasification was not carried out but the results on maximum efficiency were obtained from computer simulation of gasification.
- Full Text:
Community development and rural poverty in Zimbabwe : a policy perspective
- Authors: Chatindo, Annah
- Date: 2016
- Subjects: Community development -- Zimbabwe Rural development -- Government policy -- Zimbabwe Poverty -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/6092 , vital:29490
- Description: There is persistence of rural poverty in African countries despite efforts by governments to implement community development projects to curb poverty in impoverished rural communities. Zimbabwe adopted the Poverty Alleviation Action Plan (PAAP) under which community development programme was initiated. Community development projects by NGOs and government did not manage to meet the needs of the impoverished communities in Mvuma rural communities. More so, the incremental approach to policy making adopted by the government of Zimbabwe failed to embrace the principles of community development, for example, participation of community projects beneficiaries on everything that impact to their way of living. Despite all the efforts to alleviate rural poverty in Mvuma rural district there is still persistence of rural poverty, characterized by poor roads and struggling of most families to meeting basic needs. Mvuma rural communities are rich in mineral resources and water sources that can be utilized instead of relying on external resources through NGOs. This therefore, calls on the government and NGOs to collaborate towards capacitating Mvuma rural dwellers in order to help alleviate poverty. This study employed qualitative approach to research as it was aimed at describing and understanding rather than explaining human behaviour. Purposive or judgmental sampling was applied. This technique was used as the researcher wanted to get hold of the people who are directly or indirectly linked to implementation of community development projects. However, quantitative method was used to gather demographic information. The PAAP policy relevance to poverty reduction in Mvuma rural district and in Zimbabwe in general was the heart of this study.
- Full Text:
- Authors: Chatindo, Annah
- Date: 2016
- Subjects: Community development -- Zimbabwe Rural development -- Government policy -- Zimbabwe Poverty -- Zimbabwe
- Language: English
- Type: Thesis , Masters , MSoc
- Identifier: http://hdl.handle.net/10353/6092 , vital:29490
- Description: There is persistence of rural poverty in African countries despite efforts by governments to implement community development projects to curb poverty in impoverished rural communities. Zimbabwe adopted the Poverty Alleviation Action Plan (PAAP) under which community development programme was initiated. Community development projects by NGOs and government did not manage to meet the needs of the impoverished communities in Mvuma rural communities. More so, the incremental approach to policy making adopted by the government of Zimbabwe failed to embrace the principles of community development, for example, participation of community projects beneficiaries on everything that impact to their way of living. Despite all the efforts to alleviate rural poverty in Mvuma rural district there is still persistence of rural poverty, characterized by poor roads and struggling of most families to meeting basic needs. Mvuma rural communities are rich in mineral resources and water sources that can be utilized instead of relying on external resources through NGOs. This therefore, calls on the government and NGOs to collaborate towards capacitating Mvuma rural dwellers in order to help alleviate poverty. This study employed qualitative approach to research as it was aimed at describing and understanding rather than explaining human behaviour. Purposive or judgmental sampling was applied. This technique was used as the researcher wanted to get hold of the people who are directly or indirectly linked to implementation of community development projects. However, quantitative method was used to gather demographic information. The PAAP policy relevance to poverty reduction in Mvuma rural district and in Zimbabwe in general was the heart of this study.
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Comparative analysis of characteristics of the various sugarcane bagasse types in terms of gasification
- Authors: Kula, Mpumezo
- Date: 2016
- Subjects: Bagasse Sugarcane -- Breeding Coal gasification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13392 , vital:39656
- Description: The insight that the fossil fuel reserves are limited, together with concerns over security of supply (i.e. the oil crises), initiated the first raise of interest in biomass and all other renewable energy forms. However, the concern grew that global warming and the resulting climate change were enhanced by carbon dioxide (CO2) emissions resulting from fossil fuel consumption. Meanwhile, biomass energy is thought to account for 14–15percent of total world energy consumption. Hence, the exploitation and utilization of biomass energy are effective and necessary for relieving the pressures caused by environmental pollution and fossil fuel shortage (Lv et al., 2010). Recently, extensive research aimed at converting biomass to useful energy have been carried out, especially pyrolysis and gasification, which are particularly suitable for the effective and efficient utilization of biomass. Sugarcane bagasse is the main byproduct of sugarcane mill, ready available at the production site so that it may be a suitable raw material for the production of biofuels, chemicals, and electricity. Among the methods that have been previously studied, is this particular study we explore thermochemical process, gasification. The properties of sugarcane bagasse relevant to gasification are briefly reviewed. The compositions of the bagasse as a fuel are variable, especially with respect to inorganic constituents important to the critical problems of sintering, fouling and slagging. Alkali and alkaline earth metals, in combination with other fuel elements such as silica and sulfur, are responsible for many undesirable reactions in a gasifier system. The three sugarcane bagasse types namely washed, unwashed and the depithed sugarcane bagasse were subjected in different types of characterization to review and compare their characteristics for gasification. Ultimate analysis was used to determine the elemental compositions and this was helpful in estimating the energy input of the materials. Elemental compositions were determined with the CHNS analyzer which gave the percent compositions of each fuel in terms of Carbon, Hydrogen, Nitrogen, Sulphur as well as Oxygen (by difference) and the SEM/EDX which gave the elemental composition of the materials as can be viewed from the EDX. The proximate analysis which is the physical characterization of the materials was carried out to preview the behavior of the sugarcane bagasse when subjected into high temperatures as the gasification process uses very high temperatures. These were determined by the TGA and the volatile matter content; fixed carbon content, moisture content and ash content were extrapolated from the resulting thermogram. SEM images for surface structures of the bagasse and FTIR for the structural functionality and bonding structures. The characterization of the bagasse was conducted to compare their gasification properties.
- Full Text:
- Authors: Kula, Mpumezo
- Date: 2016
- Subjects: Bagasse Sugarcane -- Breeding Coal gasification
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/13392 , vital:39656
- Description: The insight that the fossil fuel reserves are limited, together with concerns over security of supply (i.e. the oil crises), initiated the first raise of interest in biomass and all other renewable energy forms. However, the concern grew that global warming and the resulting climate change were enhanced by carbon dioxide (CO2) emissions resulting from fossil fuel consumption. Meanwhile, biomass energy is thought to account for 14–15percent of total world energy consumption. Hence, the exploitation and utilization of biomass energy are effective and necessary for relieving the pressures caused by environmental pollution and fossil fuel shortage (Lv et al., 2010). Recently, extensive research aimed at converting biomass to useful energy have been carried out, especially pyrolysis and gasification, which are particularly suitable for the effective and efficient utilization of biomass. Sugarcane bagasse is the main byproduct of sugarcane mill, ready available at the production site so that it may be a suitable raw material for the production of biofuels, chemicals, and electricity. Among the methods that have been previously studied, is this particular study we explore thermochemical process, gasification. The properties of sugarcane bagasse relevant to gasification are briefly reviewed. The compositions of the bagasse as a fuel are variable, especially with respect to inorganic constituents important to the critical problems of sintering, fouling and slagging. Alkali and alkaline earth metals, in combination with other fuel elements such as silica and sulfur, are responsible for many undesirable reactions in a gasifier system. The three sugarcane bagasse types namely washed, unwashed and the depithed sugarcane bagasse were subjected in different types of characterization to review and compare their characteristics for gasification. Ultimate analysis was used to determine the elemental compositions and this was helpful in estimating the energy input of the materials. Elemental compositions were determined with the CHNS analyzer which gave the percent compositions of each fuel in terms of Carbon, Hydrogen, Nitrogen, Sulphur as well as Oxygen (by difference) and the SEM/EDX which gave the elemental composition of the materials as can be viewed from the EDX. The proximate analysis which is the physical characterization of the materials was carried out to preview the behavior of the sugarcane bagasse when subjected into high temperatures as the gasification process uses very high temperatures. These were determined by the TGA and the volatile matter content; fixed carbon content, moisture content and ash content were extrapolated from the resulting thermogram. SEM images for surface structures of the bagasse and FTIR for the structural functionality and bonding structures. The characterization of the bagasse was conducted to compare their gasification properties.
- Full Text:
Comparative analysis of characteristics of the various sugarcane bagasse types in terms of gasification
- Authors: Kula, Mpumezo
- Date: 2016
- Subjects: Bagasse Bioenergetics Sugarcane -- Breeding Solar energy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1929 , vital:27584
- Description: The insight that the fossil fuel reserves are limited, together with concerns over security of supply (i.e. the oil crises), initiated the first raise of interest in biomass and all other renewable energy forms. However, the concern grew that global warming and the resulting climate change were enhanced by carbon dioxide (CO2) emissions resulting from fossil fuel consumption. Meanwhile, biomass energy is thought to account for 14–15% of total world energy consumption. Hence, the exploitation and utilization of biomass energy are effective and necessary for relieving the pressures caused by environmental pollution and fossil fuel shortage (Lv et al., 2010). Recently, extensive research aimed at converting biomass to useful energy have been carried out, especially pyrolysis and gasification, which are particularly suitable for the effective and efficient utilization of biomass. Sugarcane bagasse is the main byproduct of sugarcane mill, ready available at the production site so that it may be a suitable raw material for the production of biofuels, chemicals, and electricity. Among the methods that have been previously studied, is this particular study we explore thermochemical process, gasification. The properties of sugarcane bagasse relevant to gasification are briefly reviewed. The compositions of the bagasse as a fuel are variable, especially with respect to inorganic constituents important to the critical problems of sintering, fouling and slagging. Alkali and alkaline earth metals, in combination with other fuel elements such as silica and sulfur, are responsible for many undesirable reactions in a gasifier system.
- Full Text:
- Authors: Kula, Mpumezo
- Date: 2016
- Subjects: Bagasse Bioenergetics Sugarcane -- Breeding Solar energy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1929 , vital:27584
- Description: The insight that the fossil fuel reserves are limited, together with concerns over security of supply (i.e. the oil crises), initiated the first raise of interest in biomass and all other renewable energy forms. However, the concern grew that global warming and the resulting climate change were enhanced by carbon dioxide (CO2) emissions resulting from fossil fuel consumption. Meanwhile, biomass energy is thought to account for 14–15% of total world energy consumption. Hence, the exploitation and utilization of biomass energy are effective and necessary for relieving the pressures caused by environmental pollution and fossil fuel shortage (Lv et al., 2010). Recently, extensive research aimed at converting biomass to useful energy have been carried out, especially pyrolysis and gasification, which are particularly suitable for the effective and efficient utilization of biomass. Sugarcane bagasse is the main byproduct of sugarcane mill, ready available at the production site so that it may be a suitable raw material for the production of biofuels, chemicals, and electricity. Among the methods that have been previously studied, is this particular study we explore thermochemical process, gasification. The properties of sugarcane bagasse relevant to gasification are briefly reviewed. The compositions of the bagasse as a fuel are variable, especially with respect to inorganic constituents important to the critical problems of sintering, fouling and slagging. Alkali and alkaline earth metals, in combination with other fuel elements such as silica and sulfur, are responsible for many undesirable reactions in a gasifier system.
- Full Text:
Consumer perceptions and microbial quality of meat sold in the informal markets of Nkonkobe and Buffalo City municipalities in the Eastern province, South Africa
- Authors: Mazizi, Bulelani Elvis
- Date: 2016
- Subjects: Meat -- Quality -- South Africa --Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15365 , vital:40401
- Description: The main objective of the study was to determine consumer perceptions and microbial quality of meat sold in the informal markets found in Nkonkobe and Buffalo City Municipalities in the Eastern Cape Province, South Africa. To determine consumer perceptions of the quality of the meat and meat products sold in the informal markets in Nkonkobe and Buffalo City Municipalities, a survey was conducted. A total of 160 consumers from two municipalities in the Eastern Cape (EC) Province of South Africa was randomly sampled and interviewed. A questionnaire was used to gather information about consumer perceptions of meat and meat products sold in the informal markets regarding their knowledge about safety, food-borne diseases, hygiene, and the quality of the meat among others. The study showed that Alice Town has a larger (66.25percent) proportion of consumers with knowledge about foodborne diseases while King Williams’s Town had a larger proportion (48.75percent) of respondents who had no knowledge about Food-borne diseases. However, a large proportion of consumers in King Williams’s Town considered vendor (82.5percent) and environmental hygiene (93.75percent) than in Alice Town. Consumers (83.75percent) in King Williams’s Town viewed the meat from street vendors to be of low quality while a small proportion (18.75percent) of consumers in Alice Town viewed it as the meat of good quality. Alice had a large proportion (61.25percent) of consumers, which had knowledge of the meat safety law than King Williams’s Town. More consumers from King Williams’s Town (31.25percent) agreed that government plays a role while Alice had a small proportion (26.25percent) which disagreed. The results also showed that consumer perceptions about the safety of meat and meat products are focused more on hygiene, neglecting other important aspects such as vending infrastructure. However, most consumers do not have enough knowledge concerning meat safety. The second study determined the microbial quality of meat sold by street vendors based in Alice and Kind Williams Town in the Eastern Cape Province South Africa. A total of 48 fresh and uncooked meat samples (beef, pork, and mutton), 48 surface contact plates and 40 water samples was collected from 4 street vendors from each town for microbial analysis (n=48). After collection, all samples were subjected to Aerobic plate count (APC), Salmonella spp, Staphylococcus aureus (Staph) and Escherichia coli (E. coli). The results revealed that Salmonella spp tested negative across all the meat samples used in the study. However, no significant differences were found in the microbial quality of meat sold by street vendors in Alice and King Williams town. Furthermore, there were no significant differences (P>0.05) between the APC of raw beef (4.8 Log CFU/g), mutton (3.7 Log CFU/g) and pork (2.8 Log CFU/g) and also the cooked beef (1.5 Log CFU/g), mutton (1.3 Log CFU/g) and pork (1.9 Log CFU/g) samples. A similar trend was observed in the values of Staphylococcus aureus (Staph) and Escherichia coli (E. coli) counts in raw and cooked meat samples. However, a positive correlation between Aerobic plate counts (APC) and Staphylococcus aureus (Staph) (P<0.001) and Escherichia coli (E. coli) (P<0.01) was found in the study. It can, therefore, be concluded that there were no differences in the microbial counts of raw and cooked meat sold in the informal markets of Nkonkobe and Buffalo City Municipalities in the Eastern Cape Province, South Africa.
- Full Text:
- Authors: Mazizi, Bulelani Elvis
- Date: 2016
- Subjects: Meat -- Quality -- South Africa --Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/15365 , vital:40401
- Description: The main objective of the study was to determine consumer perceptions and microbial quality of meat sold in the informal markets found in Nkonkobe and Buffalo City Municipalities in the Eastern Cape Province, South Africa. To determine consumer perceptions of the quality of the meat and meat products sold in the informal markets in Nkonkobe and Buffalo City Municipalities, a survey was conducted. A total of 160 consumers from two municipalities in the Eastern Cape (EC) Province of South Africa was randomly sampled and interviewed. A questionnaire was used to gather information about consumer perceptions of meat and meat products sold in the informal markets regarding their knowledge about safety, food-borne diseases, hygiene, and the quality of the meat among others. The study showed that Alice Town has a larger (66.25percent) proportion of consumers with knowledge about foodborne diseases while King Williams’s Town had a larger proportion (48.75percent) of respondents who had no knowledge about Food-borne diseases. However, a large proportion of consumers in King Williams’s Town considered vendor (82.5percent) and environmental hygiene (93.75percent) than in Alice Town. Consumers (83.75percent) in King Williams’s Town viewed the meat from street vendors to be of low quality while a small proportion (18.75percent) of consumers in Alice Town viewed it as the meat of good quality. Alice had a large proportion (61.25percent) of consumers, which had knowledge of the meat safety law than King Williams’s Town. More consumers from King Williams’s Town (31.25percent) agreed that government plays a role while Alice had a small proportion (26.25percent) which disagreed. The results also showed that consumer perceptions about the safety of meat and meat products are focused more on hygiene, neglecting other important aspects such as vending infrastructure. However, most consumers do not have enough knowledge concerning meat safety. The second study determined the microbial quality of meat sold by street vendors based in Alice and Kind Williams Town in the Eastern Cape Province South Africa. A total of 48 fresh and uncooked meat samples (beef, pork, and mutton), 48 surface contact plates and 40 water samples was collected from 4 street vendors from each town for microbial analysis (n=48). After collection, all samples were subjected to Aerobic plate count (APC), Salmonella spp, Staphylococcus aureus (Staph) and Escherichia coli (E. coli). The results revealed that Salmonella spp tested negative across all the meat samples used in the study. However, no significant differences were found in the microbial quality of meat sold by street vendors in Alice and King Williams town. Furthermore, there were no significant differences (P>0.05) between the APC of raw beef (4.8 Log CFU/g), mutton (3.7 Log CFU/g) and pork (2.8 Log CFU/g) and also the cooked beef (1.5 Log CFU/g), mutton (1.3 Log CFU/g) and pork (1.9 Log CFU/g) samples. A similar trend was observed in the values of Staphylococcus aureus (Staph) and Escherichia coli (E. coli) counts in raw and cooked meat samples. However, a positive correlation between Aerobic plate counts (APC) and Staphylococcus aureus (Staph) (P<0.001) and Escherichia coli (E. coli) (P<0.01) was found in the study. It can, therefore, be concluded that there were no differences in the microbial counts of raw and cooked meat sold in the informal markets of Nkonkobe and Buffalo City Municipalities in the Eastern Cape Province, South Africa.
- Full Text:
Creation and detection of Vector Bessel Beams
- Omoefe, Idisi David, Forbes, Andrew
- Authors: Omoefe, Idisi David , Forbes, Andrew
- Date: 2016
- Subjects: Vector analysis Quantum theory
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1785 , vital:27558
- Description: Bessel beams are optical fields which falls into the category of non-diffracting beams. Vector Bessel beams are vector beams possessing cylindrical symmetry. Cylindrically symmetric beams tend to have a tight focal point during propagation. The tight focal beam nature of vector Bessel beams makes them a good potential in various facets of science such as biological optical trapping, wireless communications, remote sensing, microscopy etc. In this research work, vector Bessel beams were generated using the phase of an Axicon that was encoded into a spatial light modulator. Firstly, scalar Bessel beams which possess linear polarization were generated and converted to circularly polarized vector beams by the use of a q-plate. The orbital angular momentum (OAM) modes that are embedded in the vortex beams were detected using modal decomposition technique. This was implemented for both the scalar and vector case using a quarter wave plate. The measure of the degree of non-separability of the vector Bessel beams using tomographic quantum tools was also implemented where the density matrix was reconstructed. The concurrence and fidelity which explore the measure of vectorness of both scalar and vector Bessel beams were calculated from the density matrix. The obtained results show that the spatial modes and polarization are coupled in the vector case as expected.
- Full Text:
- Authors: Omoefe, Idisi David , Forbes, Andrew
- Date: 2016
- Subjects: Vector analysis Quantum theory
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1785 , vital:27558
- Description: Bessel beams are optical fields which falls into the category of non-diffracting beams. Vector Bessel beams are vector beams possessing cylindrical symmetry. Cylindrically symmetric beams tend to have a tight focal point during propagation. The tight focal beam nature of vector Bessel beams makes them a good potential in various facets of science such as biological optical trapping, wireless communications, remote sensing, microscopy etc. In this research work, vector Bessel beams were generated using the phase of an Axicon that was encoded into a spatial light modulator. Firstly, scalar Bessel beams which possess linear polarization were generated and converted to circularly polarized vector beams by the use of a q-plate. The orbital angular momentum (OAM) modes that are embedded in the vortex beams were detected using modal decomposition technique. This was implemented for both the scalar and vector case using a quarter wave plate. The measure of the degree of non-separability of the vector Bessel beams using tomographic quantum tools was also implemented where the density matrix was reconstructed. The concurrence and fidelity which explore the measure of vectorness of both scalar and vector Bessel beams were calculated from the density matrix. The obtained results show that the spatial modes and polarization are coupled in the vector case as expected.
- Full Text:
Critical analysis of the implementation of government-wide monitoring and evaluation system in Eastern Cape municipalities - case study of Chris Hani District Municipality
- Authors: Mviko, Vuyiseka Nosipho
- Date: 2016
- Subjects: Government productivity -- South Africa -- Eastern Cape -- Evaluation Management information systems Government accountability
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2877 , vital:28117
- Description: South Africa is faced with enormous backlog of service delivery which is attributed to the apartheid government and performance challenges especially in areas like Eastern Cape. It was then identified that there was no uniform system to monitor and evaluate performance of government institutions and the impact of the services they render to the community. The government then adopted a monitoring and evaluation system called Government - Wide Monitoring and Evaluation System for all government departments and municipalities. This study analysed the implementation of this Government-Wide Monitoring and Evaluation System in Eastern Cape Municipalities with specific reference to Chris Hani District Municipality. It further assessed the effectiveness of this monitoring and evaluation system and whether its implementation has improved performance in municipalities, so as to identify the hampering limitations and the appropriate improvement strategies that can be recommended. In order to reach conclusions to the questions and objectives, the study was conducted using qualitative research methodology. Interviews were conducted as described in chapter 3. Chapter 4 presents the findings that were achieved from the interviews and the interpretation of these findings whilst chapter 5 presents conclusion and recommendations based on the findings.
- Full Text:
- Authors: Mviko, Vuyiseka Nosipho
- Date: 2016
- Subjects: Government productivity -- South Africa -- Eastern Cape -- Evaluation Management information systems Government accountability
- Language: English
- Type: Thesis , Masters , MPA
- Identifier: http://hdl.handle.net/10353/2877 , vital:28117
- Description: South Africa is faced with enormous backlog of service delivery which is attributed to the apartheid government and performance challenges especially in areas like Eastern Cape. It was then identified that there was no uniform system to monitor and evaluate performance of government institutions and the impact of the services they render to the community. The government then adopted a monitoring and evaluation system called Government - Wide Monitoring and Evaluation System for all government departments and municipalities. This study analysed the implementation of this Government-Wide Monitoring and Evaluation System in Eastern Cape Municipalities with specific reference to Chris Hani District Municipality. It further assessed the effectiveness of this monitoring and evaluation system and whether its implementation has improved performance in municipalities, so as to identify the hampering limitations and the appropriate improvement strategies that can be recommended. In order to reach conclusions to the questions and objectives, the study was conducted using qualitative research methodology. Interviews were conducted as described in chapter 3. Chapter 4 presents the findings that were achieved from the interviews and the interpretation of these findings whilst chapter 5 presents conclusion and recommendations based on the findings.
- Full Text:
Crop rotation and crop residue management effects under no till on the soil quality of two ecotopes in the Eastern Cape, South Africa
- Authors: Isaac, Gura
- Date: 2016
- Subjects: Crop rotation Crops and soils Soil fertility
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2934 , vital:28144
- Description: The degradation of soil quality due to undesirable farming practices has reached alarming scales in the Eastern Cape and this has had negative repercussions on soil productivity and the environment in general. There is growing evidence that conservation agriculture (CA) practices involving minimal mechanical disturbance, maintaining permanent surface cover and embracing diverse crop rotations increase soil organic carbon (SOC) and therefore has potential to mitigate soil quality deterioration. A study was carried out at two sites located in two ecotopes to investigate the effects of crop residue retention and crop rotations in a no till system on overall soil quality using the Soil Management Assessment Framework (SMAF) as the soil quality assessment tool. The CA study trials were laid out in 2012 at two different locations, one at the Phandulwazi Agricultural High school within the Phandulwazi Jozini ecotope and the other one at University of Fort Hare Research Farm within the Alice Jozini ecotope. The experiment was laid out as a split-split plot arrangement in a randomized complete block design with three replicates. Tillage treatments were applied on the main plots while crop rotation treatments were applied as subplots. Crop residue retention treatments were applied as sub-sub plots. The rotational treatments were maize-fallow-maize (MFM), maize-fallow-soybean (MFS), maize-wheat-maize (MWM) and maize-wheat-soybean (MWS). The initial assessment of the overall soil quality of the two ecotopes using the SMAF soil quality index (SQI) revealed that the soils at the Alice site were functioning at 80% while the soils at the Phandulwazi site were functioning at 79 percent of their optimum capacity. The slight difference in the soil quality of the two ecotopes could be attributed to their different soil organic C contents where the Alice Jozini ecotope had significantly higher soil organic C contents than the Phandulwazi Jozini ecotope. After 3 years of continuous treatment application, crop residue retention significantly improved most of the measured soil quality parameters. Generally across the sites, more soil organic C, microbial biomass C (MBC), ß-glucosidase (BG) activity, mineral N, extractable P and K, Cu, Zn, Mn, Fe, and macro-aggregates were recorded in treatments where crop residues were retained. Crop rotations alone did not have a significant impact on most of the measured soil quality indicators. The crop rotations influenced significantly the availability of mineral N across the two sites, highlighting the importance of using a legume in rotations on available N for the subsequent crops. Most of the measured soil attributes were not significantly influenced after 3 years of continuously applying combined treatment of CA components. Mineral N (NO3 + NH4), K, Zn and Fe were significantly impacted on by the interactions of CA components at the Phandulwazi site, while N, Cu, Zn and Mn were significantly increased at the Alice site. Low response of SOC to combined CA treatments in the short-term prompted the need to examine treatment effects on individual soil carbon fractions. The interaction of crop rotation and residue management techniques were significant on the fine particulate organic matter – C fractions and microbially respired C. These soil C fractions were more sensitive to short-term treatments of combined CA components than SOC and MBC, therefore they can be used as short-term indicators of CA effects on SOM. Soil organic carbon, MBC, extractable P and K, soil pH, EC, b, AGS (aggregate stability) and BG activity were measured and the Soil Management Assessment Framework (SMAF) used to calculate soil quality index (SQI) values for each treatment. The combination of the crop rotations with crop residue retention showed the potential to significantly improve SQI values in the long term. The highest soil quality improvement at both sites was achieved by the maize-wheat-soybean (MWS) rotation with crop residue retention.
- Full Text:
- Authors: Isaac, Gura
- Date: 2016
- Subjects: Crop rotation Crops and soils Soil fertility
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2934 , vital:28144
- Description: The degradation of soil quality due to undesirable farming practices has reached alarming scales in the Eastern Cape and this has had negative repercussions on soil productivity and the environment in general. There is growing evidence that conservation agriculture (CA) practices involving minimal mechanical disturbance, maintaining permanent surface cover and embracing diverse crop rotations increase soil organic carbon (SOC) and therefore has potential to mitigate soil quality deterioration. A study was carried out at two sites located in two ecotopes to investigate the effects of crop residue retention and crop rotations in a no till system on overall soil quality using the Soil Management Assessment Framework (SMAF) as the soil quality assessment tool. The CA study trials were laid out in 2012 at two different locations, one at the Phandulwazi Agricultural High school within the Phandulwazi Jozini ecotope and the other one at University of Fort Hare Research Farm within the Alice Jozini ecotope. The experiment was laid out as a split-split plot arrangement in a randomized complete block design with three replicates. Tillage treatments were applied on the main plots while crop rotation treatments were applied as subplots. Crop residue retention treatments were applied as sub-sub plots. The rotational treatments were maize-fallow-maize (MFM), maize-fallow-soybean (MFS), maize-wheat-maize (MWM) and maize-wheat-soybean (MWS). The initial assessment of the overall soil quality of the two ecotopes using the SMAF soil quality index (SQI) revealed that the soils at the Alice site were functioning at 80% while the soils at the Phandulwazi site were functioning at 79 percent of their optimum capacity. The slight difference in the soil quality of the two ecotopes could be attributed to their different soil organic C contents where the Alice Jozini ecotope had significantly higher soil organic C contents than the Phandulwazi Jozini ecotope. After 3 years of continuous treatment application, crop residue retention significantly improved most of the measured soil quality parameters. Generally across the sites, more soil organic C, microbial biomass C (MBC), ß-glucosidase (BG) activity, mineral N, extractable P and K, Cu, Zn, Mn, Fe, and macro-aggregates were recorded in treatments where crop residues were retained. Crop rotations alone did not have a significant impact on most of the measured soil quality indicators. The crop rotations influenced significantly the availability of mineral N across the two sites, highlighting the importance of using a legume in rotations on available N for the subsequent crops. Most of the measured soil attributes were not significantly influenced after 3 years of continuously applying combined treatment of CA components. Mineral N (NO3 + NH4), K, Zn and Fe were significantly impacted on by the interactions of CA components at the Phandulwazi site, while N, Cu, Zn and Mn were significantly increased at the Alice site. Low response of SOC to combined CA treatments in the short-term prompted the need to examine treatment effects on individual soil carbon fractions. The interaction of crop rotation and residue management techniques were significant on the fine particulate organic matter – C fractions and microbially respired C. These soil C fractions were more sensitive to short-term treatments of combined CA components than SOC and MBC, therefore they can be used as short-term indicators of CA effects on SOM. Soil organic carbon, MBC, extractable P and K, soil pH, EC, b, AGS (aggregate stability) and BG activity were measured and the Soil Management Assessment Framework (SMAF) used to calculate soil quality index (SQI) values for each treatment. The combination of the crop rotations with crop residue retention showed the potential to significantly improve SQI values in the long term. The highest soil quality improvement at both sites was achieved by the maize-wheat-soybean (MWS) rotation with crop residue retention.
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Design and implementation of a multi-agent opportunistic grid computing platform
- Authors: Muranganwa, Raymond
- Date: 2016
- Subjects: Computational grids (Computer systems)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2722 , vital:28064
- Description: Opportunistic Grid Computing involves joining idle computing resources in enterprises into a converged high performance commodity infrastructure. The research described in this dissertation investigates the viability of public resource computing in offering a plethora of possibilities through seamless access to shared compute and storage resources. The research proposes and conceptualizes the Multi-Agent Opportunistic Grid (MAOG) solution in an Information and Communication Technologies for Development (ICT4D) initiative to address some limitations prevalent in traditional distributed system implementations. Proof-of-concept software components based on JADE (Java Agent Development Framework) validated Multi-Agent Systems (MAS) as an important tool for provisioning of Opportunistic Grid Computing platforms. Exploration of agent technologies within the research context identified two key components which improve access to extended computer capabilities. The first component is a Mobile Agent (MA) compute component in which a group of agents interact to pool shared processor cycles. The compute component integrates dynamic resource identification and allocation strategies by incorporating the Contract Net Protocol (CNP) and rule based reasoning concepts. The second service is a MAS based storage component realized through disk mirroring and Google file-system’s chunking with atomic append storage techniques. This research provides a candidate Opportunistic Grid Computing platform design and implementation through the use of MAS. Experiments conducted validated the design and implementation of the compute and storage services. From results, support for processing user applications; resource identification and allocation; and rule based reasoning validated the MA compute component. A MAS based file-system that implements chunking optimizations was considered to be optimum based on evaluations. The findings from the undertaken experiments also validated the functional adequacy of the implementation, and show the suitability of MAS for provisioning of robust, autonomous, and intelligent platforms. The context of this research, ICT4D, provides a solution to optimizing and increasing the utilization of computing resources that are usually idle in these contexts.
- Full Text:
- Authors: Muranganwa, Raymond
- Date: 2016
- Subjects: Computational grids (Computer systems)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2722 , vital:28064
- Description: Opportunistic Grid Computing involves joining idle computing resources in enterprises into a converged high performance commodity infrastructure. The research described in this dissertation investigates the viability of public resource computing in offering a plethora of possibilities through seamless access to shared compute and storage resources. The research proposes and conceptualizes the Multi-Agent Opportunistic Grid (MAOG) solution in an Information and Communication Technologies for Development (ICT4D) initiative to address some limitations prevalent in traditional distributed system implementations. Proof-of-concept software components based on JADE (Java Agent Development Framework) validated Multi-Agent Systems (MAS) as an important tool for provisioning of Opportunistic Grid Computing platforms. Exploration of agent technologies within the research context identified two key components which improve access to extended computer capabilities. The first component is a Mobile Agent (MA) compute component in which a group of agents interact to pool shared processor cycles. The compute component integrates dynamic resource identification and allocation strategies by incorporating the Contract Net Protocol (CNP) and rule based reasoning concepts. The second service is a MAS based storage component realized through disk mirroring and Google file-system’s chunking with atomic append storage techniques. This research provides a candidate Opportunistic Grid Computing platform design and implementation through the use of MAS. Experiments conducted validated the design and implementation of the compute and storage services. From results, support for processing user applications; resource identification and allocation; and rule based reasoning validated the MA compute component. A MAS based file-system that implements chunking optimizations was considered to be optimum based on evaluations. The findings from the undertaken experiments also validated the functional adequacy of the implementation, and show the suitability of MAS for provisioning of robust, autonomous, and intelligent platforms. The context of this research, ICT4D, provides a solution to optimizing and increasing the utilization of computing resources that are usually idle in these contexts.
- Full Text:
Determinants of participation in beekeeping and its contribution to rural household income: the case of O. R. Tambo Municipality, Eastern Cape Province, South Africa
- Authors: Ncetani, Nelisiwe
- Date: 2016
- Subjects: Beekeepers -- South Africa -- Eastern Cape Sustainable living -- South Africa -- Eastern Cape Home economics, Rural -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1486 , vital:27299
- Description: This dissertation explores determinants and perceptions to participation in beekeeping by households’ as well as its contribution to household income. This is in a context that smallholder farmers’ participation is reported to be very low, despite several claimed benefits of beekeeping. Moreover, despite receiving substantial endorsements as a resilient climate-smart rural livelihood, off-farm, forest, non-timber diversification strategy; the uptake of beekeeping by smallholder farmers in the Eastern Cape Province of South Africa still remains very low. Against this background, this study used cross-sectional survey data to gauge smallholder farmers’ perceptions and factors that influence their participation in beekeeping using a binary regression model; further, it measured the contribution of beekeeping to rural household income using a linear regression model. Descriptive statistics revealed that majority of the people from the study area have positive perceptions regarding beekeeping. Regression estimates further indicate that beekeeping is mostly conditioned by shared perceptions, institutional and socio-economic factors that are worth targeting to promote the uptake of beekeeping as a livelihood. Public policies that influence the institutional framework (extension, credit and market) in favour of beekeeping are more likely to promote participation in beekeeping activities. Also, more research on the documentation and benefits of beekeeping supported by investments targeting educational campaigns towards promoting positive attitudes and dispelling fears and myths surrounding beekeeping as an enterprise, will also promote the participation of smallholder farmers in beekeeping. Regression estimates for determinants of household income revealed a significant positive contribution of beekeeping to household income, education, gender and age. Promotion of beekeeping may therefore address household income that is worth targeting to address rural poverty. The study therefore concludes that to fully unlock the income potential of beekeeping for smallholder farmers, development agencies need to address several negative perceptions and institutional factors that affect beekeeping participation, while more research is required to quantify the claimed benefits of beekeeping, given their positive potential to promote farmers’ interests in beekeeping.
- Full Text:
- Authors: Ncetani, Nelisiwe
- Date: 2016
- Subjects: Beekeepers -- South Africa -- Eastern Cape Sustainable living -- South Africa -- Eastern Cape Home economics, Rural -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/1486 , vital:27299
- Description: This dissertation explores determinants and perceptions to participation in beekeeping by households’ as well as its contribution to household income. This is in a context that smallholder farmers’ participation is reported to be very low, despite several claimed benefits of beekeeping. Moreover, despite receiving substantial endorsements as a resilient climate-smart rural livelihood, off-farm, forest, non-timber diversification strategy; the uptake of beekeeping by smallholder farmers in the Eastern Cape Province of South Africa still remains very low. Against this background, this study used cross-sectional survey data to gauge smallholder farmers’ perceptions and factors that influence their participation in beekeeping using a binary regression model; further, it measured the contribution of beekeeping to rural household income using a linear regression model. Descriptive statistics revealed that majority of the people from the study area have positive perceptions regarding beekeeping. Regression estimates further indicate that beekeeping is mostly conditioned by shared perceptions, institutional and socio-economic factors that are worth targeting to promote the uptake of beekeeping as a livelihood. Public policies that influence the institutional framework (extension, credit and market) in favour of beekeeping are more likely to promote participation in beekeeping activities. Also, more research on the documentation and benefits of beekeeping supported by investments targeting educational campaigns towards promoting positive attitudes and dispelling fears and myths surrounding beekeeping as an enterprise, will also promote the participation of smallholder farmers in beekeeping. Regression estimates for determinants of household income revealed a significant positive contribution of beekeeping to household income, education, gender and age. Promotion of beekeeping may therefore address household income that is worth targeting to address rural poverty. The study therefore concludes that to fully unlock the income potential of beekeeping for smallholder farmers, development agencies need to address several negative perceptions and institutional factors that affect beekeeping participation, while more research is required to quantify the claimed benefits of beekeeping, given their positive potential to promote farmers’ interests in beekeeping.
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Development of a stemmer for the isiXhosa language
- Authors: Nogwina, Mnoneleli
- Date: 2016
- Subjects: Computational linguistics Language and languages Xhosa language
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2611 , vital:27938
- Description: IsiXhosa language is one of the eleven official languages and the second most widely spoken language in South Africa. However, in terms of computational linguistics, the language did not get attention and natural language related work is almost non-existent. Document retrieval using unstructured queries requires some kind of language processing, and an efficient retrieval of documents can be achieved if we use a technique called stemming. The area that involves document storage and retrieval is called Information Retrieval (IR). Basically, IR systems make use of a Stemmer to index document representations and also terms in users’ queries to retrieve matching documents. In this dissertation, we present the developed Stemmer that can be used in both conditions. The Stemmer is used in IR systems, like Google to retrieve documents written in isiXhosa. In the Eastern Cape Province of South Africa many public schools take isiXhosa as a subject and also a number of Universities in South Africa teach isiXhosa. Therefore, for a language important such as this, it is important to make valuable information that is available online accessible to users through the use of IR systems. In our efforts to develop a Stemmer for the isiXhosa language, an investigation on how others have developed Stemmers for other languages was carried out. From the investigation we came to realize that the Porter stemming algorithm in particular was the main algorithm that many of other Stemmers make use of as a reference. We found that Porter’s algorithm could not be used in its totality in the development of the isiXhosa Stemmer because of the morphological complexity of the language. We developed an affix removal that is embedded with rules that determine which order should be followed in stripping the affixes. The rule is that, the word under consideration is checked against the exceptions, if it’s not in the exceptions list then the stripping continue in the following order; Prefix removal, Suffix removal and finally save the result as stem. The Stemmer was successfully developed and was tested and evaluated in a sample data that was randomly collected from the isiXhosa text books and isiXhosa dictionary. From the results obtained we concluded that the Stemmer can be used in IR systems as it showed 91 percent accuracy. The errors were 9 percent and therefore these results are within the accepted range and therefore the Stemmer can be used to help in retrieval of isiXhosa documents. This is only a noun Stemmer and in the future it can be extended to also stem verbs as well. The Stemmer can also be used in the development of spell-checkers of isiXhosa.
- Full Text:
- Authors: Nogwina, Mnoneleli
- Date: 2016
- Subjects: Computational linguistics Language and languages Xhosa language
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/2611 , vital:27938
- Description: IsiXhosa language is one of the eleven official languages and the second most widely spoken language in South Africa. However, in terms of computational linguistics, the language did not get attention and natural language related work is almost non-existent. Document retrieval using unstructured queries requires some kind of language processing, and an efficient retrieval of documents can be achieved if we use a technique called stemming. The area that involves document storage and retrieval is called Information Retrieval (IR). Basically, IR systems make use of a Stemmer to index document representations and also terms in users’ queries to retrieve matching documents. In this dissertation, we present the developed Stemmer that can be used in both conditions. The Stemmer is used in IR systems, like Google to retrieve documents written in isiXhosa. In the Eastern Cape Province of South Africa many public schools take isiXhosa as a subject and also a number of Universities in South Africa teach isiXhosa. Therefore, for a language important such as this, it is important to make valuable information that is available online accessible to users through the use of IR systems. In our efforts to develop a Stemmer for the isiXhosa language, an investigation on how others have developed Stemmers for other languages was carried out. From the investigation we came to realize that the Porter stemming algorithm in particular was the main algorithm that many of other Stemmers make use of as a reference. We found that Porter’s algorithm could not be used in its totality in the development of the isiXhosa Stemmer because of the morphological complexity of the language. We developed an affix removal that is embedded with rules that determine which order should be followed in stripping the affixes. The rule is that, the word under consideration is checked against the exceptions, if it’s not in the exceptions list then the stripping continue in the following order; Prefix removal, Suffix removal and finally save the result as stem. The Stemmer was successfully developed and was tested and evaluated in a sample data that was randomly collected from the isiXhosa text books and isiXhosa dictionary. From the results obtained we concluded that the Stemmer can be used in IR systems as it showed 91 percent accuracy. The errors were 9 percent and therefore these results are within the accepted range and therefore the Stemmer can be used to help in retrieval of isiXhosa documents. This is only a noun Stemmer and in the future it can be extended to also stem verbs as well. The Stemmer can also be used in the development of spell-checkers of isiXhosa.
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Development of part-of-speech tagger for Xhosa
- Authors: Delman, Xolani
- Date: 2016
- Subjects: Computational linguistics -- Methodology Natural language processing (Computer science) Linguistic models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11872 , vital:39114
- Description: Part-of-Speech (POS) tagging is a process of assigning an appropriate part of speech or lexical category to each word in a given sentence of a particular natural language. Natural languages are languages that human beings use to communicate with one another be it Xhosa, Zulu, English etc. POS tagging plays a huge and important role in natural language processing applications. The main applications of POS tagging include machine translation, parsing, text chunking, spell checkiXhosa (sometimes referred to as isiXhosa) is one of the eleven official languages of South Africa and is spoken by over 8 million South Africans. The language is mainly spoken in the Eastern Cape and Western Cape provinces of the country. It is the second most widely spoken native language in South Africa after Zulu (sometimes called isiZulu). Although the number of speakers might seem to be high, Xhosa is considerably under-resourced. There are very few publications in Xhosa, very few books have been published in the language and also the domains that use the language as a medium of instruction are very limited. However, the language is finding momentum nowadays. An Oxford approved Xhosa dictionary has been developed recently, and Xhosa newspapers that did not exist in the recent past are now published. Text from previously mentioned sources can then be combined to formulate a larger text that can be used to train the tagger. This work aims to develop an effective POS tagger for Xhosa. g and grammar. This thesis presents/describes the work that needed to be done to produce an automatic POS tagger for Xhosa. A tagset consisting of 36 POS tags/labels for the language were used for this purpose. These are listed. A total of 5000 words were manually tagged/labelled for the purpose of training the tagger. Another 3000 words were used for testing the tagger and these were disjoint from the manually tagged training data. The open source Stanford CoreNLP toolkit was used to create the tagger. The toolkit implements a Maximum Entropy machine learning model which was applied in the development of the tagger presented in this thesis. The thesis describes the implementation and testing processes of the model in detail. The results show that the development of the Xhosa POS tagging model was successful. This model managed to obtain a tagging accuracy of 87.71 percent.
- Full Text:
- Authors: Delman, Xolani
- Date: 2016
- Subjects: Computational linguistics -- Methodology Natural language processing (Computer science) Linguistic models
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/11872 , vital:39114
- Description: Part-of-Speech (POS) tagging is a process of assigning an appropriate part of speech or lexical category to each word in a given sentence of a particular natural language. Natural languages are languages that human beings use to communicate with one another be it Xhosa, Zulu, English etc. POS tagging plays a huge and important role in natural language processing applications. The main applications of POS tagging include machine translation, parsing, text chunking, spell checkiXhosa (sometimes referred to as isiXhosa) is one of the eleven official languages of South Africa and is spoken by over 8 million South Africans. The language is mainly spoken in the Eastern Cape and Western Cape provinces of the country. It is the second most widely spoken native language in South Africa after Zulu (sometimes called isiZulu). Although the number of speakers might seem to be high, Xhosa is considerably under-resourced. There are very few publications in Xhosa, very few books have been published in the language and also the domains that use the language as a medium of instruction are very limited. However, the language is finding momentum nowadays. An Oxford approved Xhosa dictionary has been developed recently, and Xhosa newspapers that did not exist in the recent past are now published. Text from previously mentioned sources can then be combined to formulate a larger text that can be used to train the tagger. This work aims to develop an effective POS tagger for Xhosa. g and grammar. This thesis presents/describes the work that needed to be done to produce an automatic POS tagger for Xhosa. A tagset consisting of 36 POS tags/labels for the language were used for this purpose. These are listed. A total of 5000 words were manually tagged/labelled for the purpose of training the tagger. Another 3000 words were used for testing the tagger and these were disjoint from the manually tagged training data. The open source Stanford CoreNLP toolkit was used to create the tagger. The toolkit implements a Maximum Entropy machine learning model which was applied in the development of the tagger presented in this thesis. The thesis describes the implementation and testing processes of the model in detail. The results show that the development of the Xhosa POS tagging model was successful. This model managed to obtain a tagging accuracy of 87.71 percent.
- Full Text:
Diversity and distribution of lepidopteran stem borers and their wild host plants in Western Cape and KwaZulu-Natal provinces, South Africa
- Authors: Kokwana, Bongiwe
- Date: 2016
- Subjects: Stem borers--South Africa Pests--South Africa Grain--Diseases--South Africa
- Language: English
- Type: Thesis , Masters , Entomology
- Identifier: http://hdl.handle.net/10353/11729 , vital:39101
- Description: Lepidopteran stem borers are infamous among cereal crops and sugarcane growers because of their pests status in these crops. Lepidopteran stem borers often infest cereal crops such as maize (Zea mays L.), sorghum (Sorghum bicolor L.), pearl millet (Pennisetum glaucum L.), sugarcane (Saccharum spp.). However, in natural habitats, the stem borers feed on a wide variety of wild host plants species in the Poaceae, Cyperaceae and Typhaceae families. Some wild host plants in close approximation of cultivated fields act as reservoirs for stem borers during the absence of cultivated crops. Understanding of the diversity of the stem borers, their host plants and their interactions was very important in development of management strategies for the stem borer populations. For an example, grasses such as Napier grass (Pennisetum purpureum Schumach.) and Sudan grass(Sorghum vulgare var. Sudanense (Piper) Hitchc.) act as trap plants whereas other grasses such as Molasses grass (Melinis minutiflora P. Beauv.) and legume silverleaf (Desmodium uncinatum (Jacq.) DC.) act as repellents to stem borer moths. In South Africa, studies on the diversity and distribution of lepidopteran stem borers in wild habitats are limited. Previous studies concentrated on diversity, abundance, and distribution of stem borers and their natural enemies on cultivated crops because of the economic importance of cultivated crops. In view of the foregoing, this study was conducted to investigate the diversity and distribution of lepidopteran stem borers and their host plants in wild habitats in the Western Cape and KwaZulu-Natal Provinces of South Africa and to generate mtDNA COI sequences of the stem borer species in natural habitats. These sequences can be accessed in databases and assist in identification of previously unknown stem borers in cultivated crops. Therefore this study contributes to development of monitoring and early identification tool of the stem borer movements between host plants assemblages. Surveys were conducted in Western Cape and KwaZulu-Natal provinces, South Africa during the rainy season of 2014 and 2015 in 38 localities to catalogue the diversity of lepidopteran stem borers in wild host plants. The sites visited belonged to five vegetation types: grassland, the Indian Ocean coastal belt, savanna, forest, and wetlands. A total of 237 lepidopteran stem borers was collected during study yielding 21 species that belonged to Noctuidae (Acrapex sp. 89, Acrapex sp. 90, Acrapex sp. 92, Acrapex sp., Acrapex minima, New genus NG11), Sesamia calamistis Hampson, Sesamia sp., Sesamia natalensis Le rü sp. nov., Sesamia nov sp. 4, Sesamia nov sp.36, Conicofrontia bipartita Hampson, Conicofrontia sesamoides Hampson, Conicofrontia diamensa Hampson, Pirateolea piscator Fletcher , Sciomesa mesophaea Aurivillius), Crambidae(Chilo partellus Swinhoe and Calamotropha paludella Hibner) Pyralidae (Phycitiinae sp. 1 and Phycitiinae sp. 2) and Tortricidae were recorded from 20 wild host plant species. Stem borer wild host plants species were Cymbopogon dieterlenii Stapf ex Schweick.,Cymbopogon nardus (L.) Rendle, Cymbopogon pospischilii (K. Schum.) C.E. Hubb., Digitaria macroglossa Henrad, Eriochloa meyeriana (Nees) Pilg.,Eriochloa fatmensis (Hochst. &Steud.) Clayton, Imperata cylindrica (L.) Raeusch., Miscanthus capensis (Nees) Andersson, Paspalum urvillei Steud., Panicum maximumJacq., Pennisetum purpureum Schumach., Phragmites australis (Cav.) Trin. Ex Steud.,Rottboellia cochinchinensis (Lour.) Clayton, Setaria homonyma (Steud.) Chiov.,Sorghum arundinaceum (Desv.) Stapf.,Cyperus divesDelile, Cyperu sdistans Pursh, Cyperus fastigiatus Rottb., Cyperus sexangularis Nees and Typha latifolia (L.).The diversity of stem borer species varied among vegetation types, host plants, and altitude. Morphological identification of specimens from these surveys indicated a high diversity of stem borer species in the Noctuidae family, followed by Pyralidae, Crambidae, and Tortricidae respectively. Of all the stem borers collected in the two provinces, noctuid species were most abundant in all vegetation types from low to high altitudes representing 62.45percent, whereas pyralids, crambids, and tortricids made up 26.58percent, 9.28percent, and 1.69percent respectively. The diversity and distribution of stem borers were affected by latitude. KwaZulu-Natal had higher latitudes ranging between -28.37717˚ and -31.07800˚ and had higher diversity, distribution and the of stem borers host plants, while Western Cape Province had lower diversity and distribution at latitudes ranging between -34.00280˚ and -34.05343˚. Morphological identification of stem borers was complemented with the mtDNA cytochrome oxidase I gene (COI) to investigate evolutionary relationships between the stem borer species collected in this study. Of the 12 sequences searched from the databases and the Genebank only five sequences were identified to species level; UFH024 was identified as Sciomesa mesophaea, the other four were identified as Conicofrontia sesamoides, Conicofrontia bipartita; and the first ever record of Calamotropha paludella in South Africa and Pirateolea piscator. Five sequences; UFH026, UFH028, UFH029, UFH030, UFH032 were only identified to order.
- Full Text:
- Authors: Kokwana, Bongiwe
- Date: 2016
- Subjects: Stem borers--South Africa Pests--South Africa Grain--Diseases--South Africa
- Language: English
- Type: Thesis , Masters , Entomology
- Identifier: http://hdl.handle.net/10353/11729 , vital:39101
- Description: Lepidopteran stem borers are infamous among cereal crops and sugarcane growers because of their pests status in these crops. Lepidopteran stem borers often infest cereal crops such as maize (Zea mays L.), sorghum (Sorghum bicolor L.), pearl millet (Pennisetum glaucum L.), sugarcane (Saccharum spp.). However, in natural habitats, the stem borers feed on a wide variety of wild host plants species in the Poaceae, Cyperaceae and Typhaceae families. Some wild host plants in close approximation of cultivated fields act as reservoirs for stem borers during the absence of cultivated crops. Understanding of the diversity of the stem borers, their host plants and their interactions was very important in development of management strategies for the stem borer populations. For an example, grasses such as Napier grass (Pennisetum purpureum Schumach.) and Sudan grass(Sorghum vulgare var. Sudanense (Piper) Hitchc.) act as trap plants whereas other grasses such as Molasses grass (Melinis minutiflora P. Beauv.) and legume silverleaf (Desmodium uncinatum (Jacq.) DC.) act as repellents to stem borer moths. In South Africa, studies on the diversity and distribution of lepidopteran stem borers in wild habitats are limited. Previous studies concentrated on diversity, abundance, and distribution of stem borers and their natural enemies on cultivated crops because of the economic importance of cultivated crops. In view of the foregoing, this study was conducted to investigate the diversity and distribution of lepidopteran stem borers and their host plants in wild habitats in the Western Cape and KwaZulu-Natal Provinces of South Africa and to generate mtDNA COI sequences of the stem borer species in natural habitats. These sequences can be accessed in databases and assist in identification of previously unknown stem borers in cultivated crops. Therefore this study contributes to development of monitoring and early identification tool of the stem borer movements between host plants assemblages. Surveys were conducted in Western Cape and KwaZulu-Natal provinces, South Africa during the rainy season of 2014 and 2015 in 38 localities to catalogue the diversity of lepidopteran stem borers in wild host plants. The sites visited belonged to five vegetation types: grassland, the Indian Ocean coastal belt, savanna, forest, and wetlands. A total of 237 lepidopteran stem borers was collected during study yielding 21 species that belonged to Noctuidae (Acrapex sp. 89, Acrapex sp. 90, Acrapex sp. 92, Acrapex sp., Acrapex minima, New genus NG11), Sesamia calamistis Hampson, Sesamia sp., Sesamia natalensis Le rü sp. nov., Sesamia nov sp. 4, Sesamia nov sp.36, Conicofrontia bipartita Hampson, Conicofrontia sesamoides Hampson, Conicofrontia diamensa Hampson, Pirateolea piscator Fletcher , Sciomesa mesophaea Aurivillius), Crambidae(Chilo partellus Swinhoe and Calamotropha paludella Hibner) Pyralidae (Phycitiinae sp. 1 and Phycitiinae sp. 2) and Tortricidae were recorded from 20 wild host plant species. Stem borer wild host plants species were Cymbopogon dieterlenii Stapf ex Schweick.,Cymbopogon nardus (L.) Rendle, Cymbopogon pospischilii (K. Schum.) C.E. Hubb., Digitaria macroglossa Henrad, Eriochloa meyeriana (Nees) Pilg.,Eriochloa fatmensis (Hochst. &Steud.) Clayton, Imperata cylindrica (L.) Raeusch., Miscanthus capensis (Nees) Andersson, Paspalum urvillei Steud., Panicum maximumJacq., Pennisetum purpureum Schumach., Phragmites australis (Cav.) Trin. Ex Steud.,Rottboellia cochinchinensis (Lour.) Clayton, Setaria homonyma (Steud.) Chiov.,Sorghum arundinaceum (Desv.) Stapf.,Cyperus divesDelile, Cyperu sdistans Pursh, Cyperus fastigiatus Rottb., Cyperus sexangularis Nees and Typha latifolia (L.).The diversity of stem borer species varied among vegetation types, host plants, and altitude. Morphological identification of specimens from these surveys indicated a high diversity of stem borer species in the Noctuidae family, followed by Pyralidae, Crambidae, and Tortricidae respectively. Of all the stem borers collected in the two provinces, noctuid species were most abundant in all vegetation types from low to high altitudes representing 62.45percent, whereas pyralids, crambids, and tortricids made up 26.58percent, 9.28percent, and 1.69percent respectively. The diversity and distribution of stem borers were affected by latitude. KwaZulu-Natal had higher latitudes ranging between -28.37717˚ and -31.07800˚ and had higher diversity, distribution and the of stem borers host plants, while Western Cape Province had lower diversity and distribution at latitudes ranging between -34.00280˚ and -34.05343˚. Morphological identification of stem borers was complemented with the mtDNA cytochrome oxidase I gene (COI) to investigate evolutionary relationships between the stem borer species collected in this study. Of the 12 sequences searched from the databases and the Genebank only five sequences were identified to species level; UFH024 was identified as Sciomesa mesophaea, the other four were identified as Conicofrontia sesamoides, Conicofrontia bipartita; and the first ever record of Calamotropha paludella in South Africa and Pirateolea piscator. Five sequences; UFH026, UFH028, UFH029, UFH030, UFH032 were only identified to order.
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Does the directors' fiduciary duty to act in the best interests of the company undermine other stakeholders' interests? : a comparative assessment of corporate sustainability
- Authors: Hamadziripi, Friedrich
- Date: 2016
- Subjects: Corporate governance -- Law and legislation Social responsibility of business Sustainable development
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10353/5916 , vital:29419
- Description: This study sets out to answer the question whether compliance with the directors’ fiduciary duty to act in the best interests of the company undermines other stakeholders’ interests and corporate sustainability. It adopts a comparative approach whereby the South African legal system is compared to that of the United Kingdom, Canada, and the United States of America where corporate scandals in the last two decades resulted in the collapse of some large companies. Qualitative research methods namely the critical and evaluation, comparative and legal historical approaches are employed. The adoption of the comparative and historical approach to this study makes it significant for company law literature. The study is hinged on two company law principles. The first one is that a company is a juristic and fictitious person. The second one is the separation of ownership and control of a company. To effectively understand how the directors’ fiduciary duty to act in the best interests of the company has evolved over time, a historical overview of fiduciary obligations is presented. Four different views about the origins of fiduciary obligations are examined. It is submitted that the old English case of Keech v Sandford1 and the South Sea Company Bubble are very significant to the development of fiduciary obligations and their assimilation into company law. Thereafter, a discussion on the nature and scope of the directors’ duty in question is presented. An analysis of the relationship between directors and the company and how rights and duties between the two legal subjects arise is also undertaken. It will be shown that the directors’ fiduciary duty to act in the best interests of the company is broken down into a number of mandatory rules. After outlining some selected company stakeholders, an argument is presented on who the legitimate beneficiaries of directors’ fiduciary obligations should be. Further, the study provides an explanation of the concept of ‘the best interests of a company’ before addressing the tension between the pursuit of sustainability and the best interests of the company. An important question in the context of this study is how can directors’ fiduciary obligations be enforced? Identifying that there is public and private enforcement of fiduciary obligations, this study focusses on private enforcement which mainly consists of judicial and administrative remedies. Judicial remedies especially the derivative action and oppression remedies will be examined. A greater part of the discussion will dwell heavily on whether the available remedies are relevant and/or effective in protecting various stakeholders’ interests. Due to the nature of the office of director, it can be contended that directors should not be held liable for every decision they make. As such, American courts have come up with what has come to be known as the business judgment rule. This rule protects directors from civil liability if they act in good faith, with due care, without any personal interest and within the director’s authority. It will be shown that the rule manifests or operates either as an abstention doctrine, as a standard of liability or as an immunity doctrine. As an abstention or standard of liability doctrine, the rule requires the plaintiff to rebut a presumption that directors acted in good faith in the best interests of the company. As an immunity doctrine, the rule requires the director to prove that s/he qualifies for the immunity.
- Full Text:
- Authors: Hamadziripi, Friedrich
- Date: 2016
- Subjects: Corporate governance -- Law and legislation Social responsibility of business Sustainable development
- Language: English
- Type: Thesis , Masters , LLM
- Identifier: http://hdl.handle.net/10353/5916 , vital:29419
- Description: This study sets out to answer the question whether compliance with the directors’ fiduciary duty to act in the best interests of the company undermines other stakeholders’ interests and corporate sustainability. It adopts a comparative approach whereby the South African legal system is compared to that of the United Kingdom, Canada, and the United States of America where corporate scandals in the last two decades resulted in the collapse of some large companies. Qualitative research methods namely the critical and evaluation, comparative and legal historical approaches are employed. The adoption of the comparative and historical approach to this study makes it significant for company law literature. The study is hinged on two company law principles. The first one is that a company is a juristic and fictitious person. The second one is the separation of ownership and control of a company. To effectively understand how the directors’ fiduciary duty to act in the best interests of the company has evolved over time, a historical overview of fiduciary obligations is presented. Four different views about the origins of fiduciary obligations are examined. It is submitted that the old English case of Keech v Sandford1 and the South Sea Company Bubble are very significant to the development of fiduciary obligations and their assimilation into company law. Thereafter, a discussion on the nature and scope of the directors’ duty in question is presented. An analysis of the relationship between directors and the company and how rights and duties between the two legal subjects arise is also undertaken. It will be shown that the directors’ fiduciary duty to act in the best interests of the company is broken down into a number of mandatory rules. After outlining some selected company stakeholders, an argument is presented on who the legitimate beneficiaries of directors’ fiduciary obligations should be. Further, the study provides an explanation of the concept of ‘the best interests of a company’ before addressing the tension between the pursuit of sustainability and the best interests of the company. An important question in the context of this study is how can directors’ fiduciary obligations be enforced? Identifying that there is public and private enforcement of fiduciary obligations, this study focusses on private enforcement which mainly consists of judicial and administrative remedies. Judicial remedies especially the derivative action and oppression remedies will be examined. A greater part of the discussion will dwell heavily on whether the available remedies are relevant and/or effective in protecting various stakeholders’ interests. Due to the nature of the office of director, it can be contended that directors should not be held liable for every decision they make. As such, American courts have come up with what has come to be known as the business judgment rule. This rule protects directors from civil liability if they act in good faith, with due care, without any personal interest and within the director’s authority. It will be shown that the rule manifests or operates either as an abstention doctrine, as a standard of liability or as an immunity doctrine. As an abstention or standard of liability doctrine, the rule requires the plaintiff to rebut a presumption that directors acted in good faith in the best interests of the company. As an immunity doctrine, the rule requires the director to prove that s/he qualifies for the immunity.
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