Public procurement reforms in Ghana: impact on the growth of the local construction industry
- Authors: Amoah, Christopher
- Date: 2017
- Subjects: Government purchasing -- Ghana Construction industry -- Ghana
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/15862 , vital:28285
- Description: Public procurement reform has become a modern phenomenon where various countries are reforming their procurement systems either to make the systems more efficient, transparent, achieve value for money, reduce or eliminate corrupt activities, to meet the requirements of donor countries or to make the system meet the international standards. Some countries also use public procurement reform as a policy tool to address socio-economic issues including the promotion of local sectors and disadvantaged groups. Ghana has not remained stagnant in this regard but has followed suit in reforming its procurement systems to address the weaknesses of the past procurement practices. However, the effectiveness of these reforms in promoting the local construction firms has not been investigated. This research therefore, investigated how the various procurement reforms instituted by the government of Ghana have impacted on the growth of the Ghanaian construction sector. A comprehensive review of the related literature revealed that there is a relationship between public procurement reforms and the growth of the local sectors as various governments in the past have managed to use their procurements levers as policy tools to address the imbalances in the socio-economic development of their citizens. A phenomenological (qualitative) research approach was adopted for this study. Accra, the capital of Ghana was chosen based on its strategic position and also because of massive construction activities currently taking place in the city. Again, many construction firms are also registered and operating in this city. The research instrument used is the interview guide made of both tick box and open ended questions. Other sources of data included archival records such as contracts awarded, the current public procurement regulations, and manuals. It was concluded after the analysis of the findings that, even though public procurement reforms have brought about improved procurement practices, the reforms have failed to have a positive impact on the growth of the local construction industry. The implication is that, the construction industry in Ghana is still dominated by foreign firms executing major government projects to the detriment of the local construction firms thereby stifling their growth. The findings also revealed that local contractors only executive minor works devoid of complexities and mainly engaged as subcontractors by foreign firms on major government projects. The findings also revealed that government has so far not instituted any radical protective laws in the procurement systems to protect the local construction firms. The research has produced a tender evaluation template with protective mechanisms such as awarding points to bidders during the tender evaluation process. The research has also produced tender evaluation formulas for calculating points for bidders and how the successful bidder is arrived at. The study provides recommendations to all stakeholders in the Ghanaian construction industry and proposes that the evaluation criteria produced by this study be used in the public procurement system to help grow the indigenous construction industry.
- Full Text:
- Date Issued: 2017
- Authors: Amoah, Christopher
- Date: 2017
- Subjects: Government purchasing -- Ghana Construction industry -- Ghana
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/15862 , vital:28285
- Description: Public procurement reform has become a modern phenomenon where various countries are reforming their procurement systems either to make the systems more efficient, transparent, achieve value for money, reduce or eliminate corrupt activities, to meet the requirements of donor countries or to make the system meet the international standards. Some countries also use public procurement reform as a policy tool to address socio-economic issues including the promotion of local sectors and disadvantaged groups. Ghana has not remained stagnant in this regard but has followed suit in reforming its procurement systems to address the weaknesses of the past procurement practices. However, the effectiveness of these reforms in promoting the local construction firms has not been investigated. This research therefore, investigated how the various procurement reforms instituted by the government of Ghana have impacted on the growth of the Ghanaian construction sector. A comprehensive review of the related literature revealed that there is a relationship between public procurement reforms and the growth of the local sectors as various governments in the past have managed to use their procurements levers as policy tools to address the imbalances in the socio-economic development of their citizens. A phenomenological (qualitative) research approach was adopted for this study. Accra, the capital of Ghana was chosen based on its strategic position and also because of massive construction activities currently taking place in the city. Again, many construction firms are also registered and operating in this city. The research instrument used is the interview guide made of both tick box and open ended questions. Other sources of data included archival records such as contracts awarded, the current public procurement regulations, and manuals. It was concluded after the analysis of the findings that, even though public procurement reforms have brought about improved procurement practices, the reforms have failed to have a positive impact on the growth of the local construction industry. The implication is that, the construction industry in Ghana is still dominated by foreign firms executing major government projects to the detriment of the local construction firms thereby stifling their growth. The findings also revealed that local contractors only executive minor works devoid of complexities and mainly engaged as subcontractors by foreign firms on major government projects. The findings also revealed that government has so far not instituted any radical protective laws in the procurement systems to protect the local construction firms. The research has produced a tender evaluation template with protective mechanisms such as awarding points to bidders during the tender evaluation process. The research has also produced tender evaluation formulas for calculating points for bidders and how the successful bidder is arrived at. The study provides recommendations to all stakeholders in the Ghanaian construction industry and proposes that the evaluation criteria produced by this study be used in the public procurement system to help grow the indigenous construction industry.
- Full Text:
- Date Issued: 2017
Azawan: precolonial musical culture and Saharawi nationalism in the refugee camps of the Hamada Desert in Algeria
- Authors: Amoros, Luis Gimenez
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59710 , vital:27641 , http://dx.doi.org/10.21504/amj.v10i1.1225
- Description: This article analyses Saharawi music as performed for the refugee community in the camps. I argue that the construction and evolution of Saharawi music in the camps is divided into two main areas: nationalism in relation to the decolonisation of Western Sahara, and maintenance of cultural values in Saharawi music found in the historical retention of the Haul modal system originating in precolonial Saharawi culture. Local audiences use the term Azawan to define the combination of nationalist sentiments and retention of their precolonial musical culture in Saharawi music.
- Full Text:
- Date Issued: 2015
- Authors: Amoros, Luis Gimenez
- Date: 2015
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/59710 , vital:27641 , http://dx.doi.org/10.21504/amj.v10i1.1225
- Description: This article analyses Saharawi music as performed for the refugee community in the camps. I argue that the construction and evolution of Saharawi music in the camps is divided into two main areas: nationalism in relation to the decolonisation of Western Sahara, and maintenance of cultural values in Saharawi music found in the historical retention of the Haul modal system originating in precolonial Saharawi culture. Local audiences use the term Azawan to define the combination of nationalist sentiments and retention of their precolonial musical culture in Saharawi music.
- Full Text:
- Date Issued: 2015
In silico analysis of plasmodium falciparum Hsp70-x for potential binding sites and hits
- Authors: Amusengeri, Arnold
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/59136 , vital:27435
- Description: Restricted access-thesis embargoed for 1 year - release date April 2019
- Full Text:
- Date Issued: 2017
- Authors: Amusengeri, Arnold
- Date: 2017
- Subjects: Uncatalogued
- Language: English
- Type: text , Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10962/59136 , vital:27435
- Description: Restricted access-thesis embargoed for 1 year - release date April 2019
- Full Text:
- Date Issued: 2017
Characterization of Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus (MRSA) in selected recreational marine waters and beach sand in the Eastern Cape Province, South Africa
- Authors: Ankabi, Olufemi Emmanuel
- Date: 2017
- Subjects: Marine microbiology -- South Africa -- Eastern Cape Staphylococcus aureus infections -- South Africa -- Eastern Cape Pathogenic microorganisms
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4992 , vital:28915
- Description: Staphylococcus aureus is a Gram-positive bacterium predominantly found on human skin and in nasal passages with 20 to 40 percent of the population carrying this organism. Although S. aureus is an unspectacular, non-motile coccoid bacterium, it is a perilous human pathogen associated with both nosocomial and community-acquired infections and it is increasingly becoming virulent and resistant to most antibiotics. It is responsible for several infections such as osteomyelitis, toxin-mediated diseases and bacteraemia, with severe infections arising from strains harbouring antibiotic resistance genes together with virulence genes. S. aureus has been largely confined to hospitals and long-term care facilities, but it is now emerging in the community in places such as recreational beach waters, and occurring in healthy individuals with no associated risk factors. This organism has been reported to be released by swimmers in beaches, suggesting that recreational waters are a potential source of community-acquired S. aureus infections. It is possibly the pathogen of greatest concern due to its intrinsic virulence, its capacity to cause various life-threatening infections, and its ability to adapt to varying environmental conditions. This study was aimed at characterizing S. aureus and methicillin-resistant S. aureus (MRSA) in Port Elizabeth, Port Alfred, Kenton-on-sea and East London beaches of the Eastern Cape Province of South Africa. This was done by investigating the occurrence, antibiotic susceptibilities, antibiotic-resistant genes and virulence genes profiles of S. aureus in the selected beaches. To achieve this aim, 249 beach sand and water samples were obtained from the beaches during the period of April 2015 to April 2016. Physico-chemical parameters of beach water was investigated on site using a multi-parameter ion specific meter during sample collection. Samples were filtered and inoculated on m-Endo agar, m-FC agar and bile aesculin azide agar for total and faecal coliform as well as Enterococci respectively. For isolation of S. aureus and MRSA, samples were cultured on Mannitol salt agar and Staph 24 agar. S. aureus was identified using morphological, Gram staining and molecular (PCR) methods. The isolates were further characterized by determining their antimicrobial resistance profiles, antibiotic resistant genes (mecA, rpoB, blaZ, ermB and tetK genes) and detection of virulent genes encoding intracellular adhesion (icaA), enterotoxin (seaA) and cytolytic toxins (PVL). The majority of study sites passed the directives of physico-chemical standards levels set by WHO during the study period. A total of 143 presumptive isolates were obtained of which 30 (30 percent) were confirmed as S. aureus with 22 (73.3 percent) of these confirmed isolates from marine water and 8 (26.7 percent) from marine sand. Upon culturing on MRSA 2 agar, 15 (50 percent) of isolates showed phonotypic resistance to methicillin. Based on Antimicrobial susceptibility tests, (22/30) 73.3 percent of the isolates showed phonotypic resistance to oxacillin. Out of the 30 isolates, 16 (53.3 percent) were mecA positive and were considered methicillin-resistant S. aureus. S. aureus showed high susceptibility to gentamycin, cefoxithin, levofloxacin, ciprofloxacin, imipenem, and chloramphenicol. A large proportion (36.67 percent to 96.7 percent) of the S. aureus isolates was resistant to penicillin G, ampicillin, oxacillin, tetracycline, clindamycin, rifampicin, vancomycin, sulfamethoxazole-Trimethoprim and erythromycin. Multiple antibiotic resistance (MAR) phenotypes were generated from 7 S. aureus isolates showing resistance to three or more antibiotics. The mecA, rpoB, blaZ, ermB and tetM genes coding for methicillin, rifampicin, βeta-lactam, erythromycin and tetracycline antibiotics resistance was detected in 5 (22.7 percent), 11 (45.8 percent), 16 (55.2 percent), 15 (71.4 percent) and 8 (72.7 percent) respectively. The PVL, icaA and seaA genes coding for virulent determinants were detected in 50, 20 and 13.3 percent of the confirmed isolates respectively. Physico-chemical and faecal indicator bacteria results obtained from this study can assist municipal authorities in developing appropriate management strategies for beaches in the study area. The findings of this study showed that the investigated beaches were contaminated with toxigenic and multi-drug resistant S. aureus strains. This emphasizes the need for the implementation of better control measures to reduce the occurrence of antibiotic resistant S. aureus and of virulent S. aureus strains in recreational waters. In our study it was established that the potential of recreational waters to be reservoirs of S. aureus should not be taken for granted, and it is important that beach goers be educated about this organism as well as other related pathogens that could affect human health, especially immuno-compromised individuals. The community should be educated on antibiotic stewardship and the detrimental effects of antibiotics abuse.
- Full Text:
- Date Issued: 2017
- Authors: Ankabi, Olufemi Emmanuel
- Date: 2017
- Subjects: Marine microbiology -- South Africa -- Eastern Cape Staphylococcus aureus infections -- South Africa -- Eastern Cape Pathogenic microorganisms
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/4992 , vital:28915
- Description: Staphylococcus aureus is a Gram-positive bacterium predominantly found on human skin and in nasal passages with 20 to 40 percent of the population carrying this organism. Although S. aureus is an unspectacular, non-motile coccoid bacterium, it is a perilous human pathogen associated with both nosocomial and community-acquired infections and it is increasingly becoming virulent and resistant to most antibiotics. It is responsible for several infections such as osteomyelitis, toxin-mediated diseases and bacteraemia, with severe infections arising from strains harbouring antibiotic resistance genes together with virulence genes. S. aureus has been largely confined to hospitals and long-term care facilities, but it is now emerging in the community in places such as recreational beach waters, and occurring in healthy individuals with no associated risk factors. This organism has been reported to be released by swimmers in beaches, suggesting that recreational waters are a potential source of community-acquired S. aureus infections. It is possibly the pathogen of greatest concern due to its intrinsic virulence, its capacity to cause various life-threatening infections, and its ability to adapt to varying environmental conditions. This study was aimed at characterizing S. aureus and methicillin-resistant S. aureus (MRSA) in Port Elizabeth, Port Alfred, Kenton-on-sea and East London beaches of the Eastern Cape Province of South Africa. This was done by investigating the occurrence, antibiotic susceptibilities, antibiotic-resistant genes and virulence genes profiles of S. aureus in the selected beaches. To achieve this aim, 249 beach sand and water samples were obtained from the beaches during the period of April 2015 to April 2016. Physico-chemical parameters of beach water was investigated on site using a multi-parameter ion specific meter during sample collection. Samples were filtered and inoculated on m-Endo agar, m-FC agar and bile aesculin azide agar for total and faecal coliform as well as Enterococci respectively. For isolation of S. aureus and MRSA, samples were cultured on Mannitol salt agar and Staph 24 agar. S. aureus was identified using morphological, Gram staining and molecular (PCR) methods. The isolates were further characterized by determining their antimicrobial resistance profiles, antibiotic resistant genes (mecA, rpoB, blaZ, ermB and tetK genes) and detection of virulent genes encoding intracellular adhesion (icaA), enterotoxin (seaA) and cytolytic toxins (PVL). The majority of study sites passed the directives of physico-chemical standards levels set by WHO during the study period. A total of 143 presumptive isolates were obtained of which 30 (30 percent) were confirmed as S. aureus with 22 (73.3 percent) of these confirmed isolates from marine water and 8 (26.7 percent) from marine sand. Upon culturing on MRSA 2 agar, 15 (50 percent) of isolates showed phonotypic resistance to methicillin. Based on Antimicrobial susceptibility tests, (22/30) 73.3 percent of the isolates showed phonotypic resistance to oxacillin. Out of the 30 isolates, 16 (53.3 percent) were mecA positive and were considered methicillin-resistant S. aureus. S. aureus showed high susceptibility to gentamycin, cefoxithin, levofloxacin, ciprofloxacin, imipenem, and chloramphenicol. A large proportion (36.67 percent to 96.7 percent) of the S. aureus isolates was resistant to penicillin G, ampicillin, oxacillin, tetracycline, clindamycin, rifampicin, vancomycin, sulfamethoxazole-Trimethoprim and erythromycin. Multiple antibiotic resistance (MAR) phenotypes were generated from 7 S. aureus isolates showing resistance to three or more antibiotics. The mecA, rpoB, blaZ, ermB and tetM genes coding for methicillin, rifampicin, βeta-lactam, erythromycin and tetracycline antibiotics resistance was detected in 5 (22.7 percent), 11 (45.8 percent), 16 (55.2 percent), 15 (71.4 percent) and 8 (72.7 percent) respectively. The PVL, icaA and seaA genes coding for virulent determinants were detected in 50, 20 and 13.3 percent of the confirmed isolates respectively. Physico-chemical and faecal indicator bacteria results obtained from this study can assist municipal authorities in developing appropriate management strategies for beaches in the study area. The findings of this study showed that the investigated beaches were contaminated with toxigenic and multi-drug resistant S. aureus strains. This emphasizes the need for the implementation of better control measures to reduce the occurrence of antibiotic resistant S. aureus and of virulent S. aureus strains in recreational waters. In our study it was established that the potential of recreational waters to be reservoirs of S. aureus should not be taken for granted, and it is important that beach goers be educated about this organism as well as other related pathogens that could affect human health, especially immuno-compromised individuals. The community should be educated on antibiotic stewardship and the detrimental effects of antibiotics abuse.
- Full Text:
- Date Issued: 2017
Official development assistance as a means to poverty alleviation: evidence from Cameroon
- Authors: Anong, Moussa Moses
- Date: 2017
- Subjects: Economic development -- Cameroon , Community development -- Cameroon Cameroon -- Economic aspects
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: http://hdl.handle.net/10948/13800 , vital:27309
- Description: Despite the increased popularity of development aid flows from rich nations to poorer ones in the form of Official Development Assistance (ODA), rampant poverty still prevails in the recipient nations. This perhaps explains the lingering debate on the effectiveness of ODA in curbing poverty. Based on Cameroon, this study aims to ascertain if ODA can be relied upon as a tool to fight poverty. The researcher seeks to determine if ODA disbursed to Cameroon has resulted in poverty alleviation among the impoverished from 1980 to 2014, be it directly or indirectly. To this effect, the first research question looks at what the possible causes of poverty in Cameroon are. The second research question dwells on the pattern of ODA to Cameroon over the study period from 1980 to 2014. The final research question seeks to determine the Cameroonian poverty levels over the same period. The definition of poverty in terms of the Human Development Index (HDI) and its three poverty determinants as utilized by the United Nations Development Programme (UNDP), is adopted as a theoretical base for this research. These determinants of poverty are life expectancy at birth, mean years of schooling, and Gross National Income (GNI) per capita. While the literature review is utilised to outline the on-going debate on the effects of ODA on economic growth and poverty alleviation, it equally provides possible causes of poverty in Cameroon. These include the prevalence of factors such as poor governance, the swindling of public funds without fear, the normalisation of bribes in return for public services, the lack of decentralized administrative and civil services, and the disproportionate distribution of state earnings. Meanwhile, secondary published data sourced from reputable multilateral bodies is used to determine the trend of ODA to Cameroon over the period from 1980 to 2014. This is then correlated with poverty figures over the same period as expressed by the three human development factors or poverty determinants. The research adopts a quantitative approach as correlations and regressions of obtained secondary data are made used of. The results of the correlations reveal that ODA may not be relied upon as a tool for alleviating poverty in Cameroon due to the statistically insignificant relationships it seems to display with all three poverty determinants. The regression results show on the one hand that ODA has insignificant relationships with life expectancy at birth and mean years of schooling, while on the other hand, ODA and GNI per capita display an inverse relationship that is judged to be statistically significant. High ODA figures can therefore be associated with lower GNI per capita values in Cameroon, based on this study. This means that ODA can be assumed to negatively affect the real income of Cameroonians. A reduction in real income might equally lead to a reduced potential to afford basic necessities like healthcare, schooling and housing. As these essentials are not provided for free in Cameroon, this reduced real income may further be held responsible for an overall deterioration of the quality of life. Based on the above findings, the researcher recommends that aid recipient governments put in place supportive systems and strong institutions that are void of corruption and unnecessary bureaucracy so as to better benefit from foreign aid inflows. African countries like Cameroon also need to develop their internal resources and use them to finance and promote their own growth instead of rely on donor funding with diminishing returns. Likewise, the government needs to improve its level of human development through diverting more funds towards developing and facilitating the poor’s access to the country’s education, healthcare, road network and basic amenities like water and sanitation. Finally, inflows in the form of loans rather than grants can better be utilized to promote positive economic growth. While loans are mostly diverted to productive activities, grants may promote dependency, rent-seeking behaviour and bureaucracy. This study is one of the few that relies on country-level data. Most existing studies on foreign aid and its related effects on poverty alleviation were conducted using cross-country data.
- Full Text:
- Date Issued: 2017
- Authors: Anong, Moussa Moses
- Date: 2017
- Subjects: Economic development -- Cameroon , Community development -- Cameroon Cameroon -- Economic aspects
- Language: English
- Type: Thesis , Masters , MPhil
- Identifier: http://hdl.handle.net/10948/13800 , vital:27309
- Description: Despite the increased popularity of development aid flows from rich nations to poorer ones in the form of Official Development Assistance (ODA), rampant poverty still prevails in the recipient nations. This perhaps explains the lingering debate on the effectiveness of ODA in curbing poverty. Based on Cameroon, this study aims to ascertain if ODA can be relied upon as a tool to fight poverty. The researcher seeks to determine if ODA disbursed to Cameroon has resulted in poverty alleviation among the impoverished from 1980 to 2014, be it directly or indirectly. To this effect, the first research question looks at what the possible causes of poverty in Cameroon are. The second research question dwells on the pattern of ODA to Cameroon over the study period from 1980 to 2014. The final research question seeks to determine the Cameroonian poverty levels over the same period. The definition of poverty in terms of the Human Development Index (HDI) and its three poverty determinants as utilized by the United Nations Development Programme (UNDP), is adopted as a theoretical base for this research. These determinants of poverty are life expectancy at birth, mean years of schooling, and Gross National Income (GNI) per capita. While the literature review is utilised to outline the on-going debate on the effects of ODA on economic growth and poverty alleviation, it equally provides possible causes of poverty in Cameroon. These include the prevalence of factors such as poor governance, the swindling of public funds without fear, the normalisation of bribes in return for public services, the lack of decentralized administrative and civil services, and the disproportionate distribution of state earnings. Meanwhile, secondary published data sourced from reputable multilateral bodies is used to determine the trend of ODA to Cameroon over the period from 1980 to 2014. This is then correlated with poverty figures over the same period as expressed by the three human development factors or poverty determinants. The research adopts a quantitative approach as correlations and regressions of obtained secondary data are made used of. The results of the correlations reveal that ODA may not be relied upon as a tool for alleviating poverty in Cameroon due to the statistically insignificant relationships it seems to display with all three poverty determinants. The regression results show on the one hand that ODA has insignificant relationships with life expectancy at birth and mean years of schooling, while on the other hand, ODA and GNI per capita display an inverse relationship that is judged to be statistically significant. High ODA figures can therefore be associated with lower GNI per capita values in Cameroon, based on this study. This means that ODA can be assumed to negatively affect the real income of Cameroonians. A reduction in real income might equally lead to a reduced potential to afford basic necessities like healthcare, schooling and housing. As these essentials are not provided for free in Cameroon, this reduced real income may further be held responsible for an overall deterioration of the quality of life. Based on the above findings, the researcher recommends that aid recipient governments put in place supportive systems and strong institutions that are void of corruption and unnecessary bureaucracy so as to better benefit from foreign aid inflows. African countries like Cameroon also need to develop their internal resources and use them to finance and promote their own growth instead of rely on donor funding with diminishing returns. Likewise, the government needs to improve its level of human development through diverting more funds towards developing and facilitating the poor’s access to the country’s education, healthcare, road network and basic amenities like water and sanitation. Finally, inflows in the form of loans rather than grants can better be utilized to promote positive economic growth. While loans are mostly diverted to productive activities, grants may promote dependency, rent-seeking behaviour and bureaucracy. This study is one of the few that relies on country-level data. Most existing studies on foreign aid and its related effects on poverty alleviation were conducted using cross-country data.
- Full Text:
- Date Issued: 2017
The sustainability of South African construction small, medium and micro enterprises
- Authors: Anugwo, Iruka Chijindu
- Date: 2017
- Subjects: Construction industry -- South Africa -- Port Elizabeth Sustainable development -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/15259 , vital:28194
- Description: The construction industry is one of the strategic sectors that drive the economic sustainability and competitiveness of any nation. However, the chronic business failure amongst the start-ups and Small, Medium and Micro Enterprises (SMMEs) in the construction industry globally is of great concern to economic prosperity for both developed and developing countries. This challenge is significantly high in the South African construction industry, where SMMEs account for 95% of the business entities, of which about 80% are most likely to exit from the market within their first five years of operation. Previous studies in this field centred on the factors that lead to construction-business failure. However, the actual operational elements of surviving SMMEs have rarely been addressed and are little understood. Thus, this research aimed to explore the strategic drivers that offer significant solutions to the challenges facing start-up contractors in the South African construction industry. The review of the related literature revealed the strategic drivers and business survival characteristics that foster SMME economic sustainability and competitiveness in the construction market. The qualitative research approach that is rooted in the phenomenological paradigm was adopted for this study. Port Elizabeth, located in the Eastern Cape Province of South Africa was the selected geographical scope for this research. Thirty-four (34) construction organisations were purposively selected from the Port Elizabeth construction industry development board (cidb) register of contractors in grades 4-6. The purposive sampling technique was adopted in selecting respondents based on the snowball approach. The research data were collected through in-depth interviewing. It was found that the SMME contractors who succeeded in their first 5 years of operation possessed the following qualities: “fundamental educational qualifications”; “experience and knowledge of construction works”; “a clear understanding of competitive business strategies and characteristics”; “critical skills and multi-skills (functional project teams)”; and “rely on strategic resources, competencies and capabilities”. Also, the significant factors contributing to the SMME contractors’ competitiveness were: “entrepreneurship skills”; “innovation and technological skills”; “leadership skills”; “education, skills training, and investment in Research and Development (R&D)”; as well as “strategic-alliance advantage”. Moreover, globalisation and internationalisation, and government support have significant potential to impact on the success and sustainability of SMME contractors. Unfortunately, these factors are under-utilised or un-strategically adopted by most of the South African SMME contractors. The research has also developed a conceptual model for sustainable performance of SMMEs based on the results and informed by the theoretical framework. The research has also developed a business-survival strategy and model for SMME contractors in the South African construction industry. The study has achieved its aim of identifying the strategic business practices, models and concepts that the surviving and active SMME contractors employed to thrive within and beyond the first five years in the industry. Based on these findings, the study recommends that the start-ups and SMME contractors should gain an insightful and strategic business knowledge on how to develop and grow a competitive and economically sustainable organisation in the industry. This should form part of their competitive business strategic models, their business review plans; and set the benchmark for performance evaluation.
- Full Text:
- Date Issued: 2017
- Authors: Anugwo, Iruka Chijindu
- Date: 2017
- Subjects: Construction industry -- South Africa -- Port Elizabeth Sustainable development -- South Africa -- Port Elizabeth
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/15259 , vital:28194
- Description: The construction industry is one of the strategic sectors that drive the economic sustainability and competitiveness of any nation. However, the chronic business failure amongst the start-ups and Small, Medium and Micro Enterprises (SMMEs) in the construction industry globally is of great concern to economic prosperity for both developed and developing countries. This challenge is significantly high in the South African construction industry, where SMMEs account for 95% of the business entities, of which about 80% are most likely to exit from the market within their first five years of operation. Previous studies in this field centred on the factors that lead to construction-business failure. However, the actual operational elements of surviving SMMEs have rarely been addressed and are little understood. Thus, this research aimed to explore the strategic drivers that offer significant solutions to the challenges facing start-up contractors in the South African construction industry. The review of the related literature revealed the strategic drivers and business survival characteristics that foster SMME economic sustainability and competitiveness in the construction market. The qualitative research approach that is rooted in the phenomenological paradigm was adopted for this study. Port Elizabeth, located in the Eastern Cape Province of South Africa was the selected geographical scope for this research. Thirty-four (34) construction organisations were purposively selected from the Port Elizabeth construction industry development board (cidb) register of contractors in grades 4-6. The purposive sampling technique was adopted in selecting respondents based on the snowball approach. The research data were collected through in-depth interviewing. It was found that the SMME contractors who succeeded in their first 5 years of operation possessed the following qualities: “fundamental educational qualifications”; “experience and knowledge of construction works”; “a clear understanding of competitive business strategies and characteristics”; “critical skills and multi-skills (functional project teams)”; and “rely on strategic resources, competencies and capabilities”. Also, the significant factors contributing to the SMME contractors’ competitiveness were: “entrepreneurship skills”; “innovation and technological skills”; “leadership skills”; “education, skills training, and investment in Research and Development (R&D)”; as well as “strategic-alliance advantage”. Moreover, globalisation and internationalisation, and government support have significant potential to impact on the success and sustainability of SMME contractors. Unfortunately, these factors are under-utilised or un-strategically adopted by most of the South African SMME contractors. The research has also developed a conceptual model for sustainable performance of SMMEs based on the results and informed by the theoretical framework. The research has also developed a business-survival strategy and model for SMME contractors in the South African construction industry. The study has achieved its aim of identifying the strategic business practices, models and concepts that the surviving and active SMME contractors employed to thrive within and beyond the first five years in the industry. Based on these findings, the study recommends that the start-ups and SMME contractors should gain an insightful and strategic business knowledge on how to develop and grow a competitive and economically sustainable organisation in the industry. This should form part of their competitive business strategic models, their business review plans; and set the benchmark for performance evaluation.
- Full Text:
- Date Issued: 2017
The impact of the farmer field school approach on small-scale vegetable farmers' knowledge, agency and production in Alice, Eastern Cape
- Authors: Apleni, Asanda
- Date: 2017
- Subjects: Agricultural extension work -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8187 , vital:31873
- Description: This study investigates the impact of the Farmer Field School approach on the knowledge, agency and production of small-scale farmers. Farmer Field Schools were devised in the 1980s by the Food and Agriculture Organization as a form of adult education in agriculture. It is a group-based approach in which a facilitator meets with farmers on a regular basis and sets in motion a process by which farmers ‘learn how to learn’, both from themselves and from one another. However, it remains an open question whether the Farmer Field School approach could be a solution to South Africa’s abiding problem of weak agricultural extension. Early in 2015, the University of Fort Hare and the Nkonkobe Farmers’ Association initiated a number of study groups in the Alice area, based largely on Farmer Field School principles. The main objective of the study was to assess the impact of the Farmer Field School approach on small-scale farmers’ knowledge, agency and production, focusing on home gardeners. The study was conducted in the Raymond Mhlaba Local Municipality in Alice of the Eastern Cape Province of South Africa. The research consisted of a survey of all the study group participants involved with home gardens, including some who joined the groups in 2015 but left in 2016. Both cross-sectional and longitudinal designs were used. Findings from this study have shown how participation in the study groups modelled on the FFS approach can improve the knowledge and skills of home gardeners, while also enabling them to produce significantly larger quantities of vegetables, and even a marketable surplus, albeit from a small base. In order to make more people to join, more incentives should be made available. Such incentives should be made available only to “kick start” the FFS study groups and take heed in prevention of dependence.
- Full Text:
- Date Issued: 2017
- Authors: Apleni, Asanda
- Date: 2017
- Subjects: Agricultural extension work -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8187 , vital:31873
- Description: This study investigates the impact of the Farmer Field School approach on the knowledge, agency and production of small-scale farmers. Farmer Field Schools were devised in the 1980s by the Food and Agriculture Organization as a form of adult education in agriculture. It is a group-based approach in which a facilitator meets with farmers on a regular basis and sets in motion a process by which farmers ‘learn how to learn’, both from themselves and from one another. However, it remains an open question whether the Farmer Field School approach could be a solution to South Africa’s abiding problem of weak agricultural extension. Early in 2015, the University of Fort Hare and the Nkonkobe Farmers’ Association initiated a number of study groups in the Alice area, based largely on Farmer Field School principles. The main objective of the study was to assess the impact of the Farmer Field School approach on small-scale farmers’ knowledge, agency and production, focusing on home gardeners. The study was conducted in the Raymond Mhlaba Local Municipality in Alice of the Eastern Cape Province of South Africa. The research consisted of a survey of all the study group participants involved with home gardens, including some who joined the groups in 2015 but left in 2016. Both cross-sectional and longitudinal designs were used. Findings from this study have shown how participation in the study groups modelled on the FFS approach can improve the knowledge and skills of home gardeners, while also enabling them to produce significantly larger quantities of vegetables, and even a marketable surplus, albeit from a small base. In order to make more people to join, more incentives should be made available. Such incentives should be made available only to “kick start” the FFS study groups and take heed in prevention of dependence.
- Full Text:
- Date Issued: 2017
The effects of changing western worldviews on morals and ethics in economics: a protestant perspective
- Authors: Appalraju, Nerusha
- Date: 2017
- Subjects: Economics -- Moral and ethical aspects , Neoclassical school of economics , Capitalism -- Religious aspects -- Protestant churches , Feminist economics , Economics -- Religious aspects , Environmental economics -- Moral and ethical aspects , Smith, Adam, 1723-1790 , Weber, Max, 1864-1920
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/32480 , vital:24050
- Description: The World Economics Association held an online conference in 2012 where they published many papers on ethics in economics. The topic of ethics in economics became more serious and popular following the 2008 financial crisis. However the case for a professional code of ethics in economics is difficult to introduce and implement due to the multidisciplinary approach of the discipline. Therefore authors such as Dow (2012), De Martino (2012), Freeman (2012) and Earl (2012) urged economists to start thinking about ethics in economics from a pluralistic view. This thesis studied the effects of changing Western worldviews on morals and ethics in economics from a Protestant perspective. Numerous authoritative sources were considered and used to create a discussion and analysis of how diverse Western worldviews impact on the type of economics which is prescribed and practiced. It was found that different Western worldviews create various standards of understanding and evaluation, which result in varying opinions on what constitutes as morally or ethically acceptable within the discipline of economics.
- Full Text:
- Date Issued: 2017
- Authors: Appalraju, Nerusha
- Date: 2017
- Subjects: Economics -- Moral and ethical aspects , Neoclassical school of economics , Capitalism -- Religious aspects -- Protestant churches , Feminist economics , Economics -- Religious aspects , Environmental economics -- Moral and ethical aspects , Smith, Adam, 1723-1790 , Weber, Max, 1864-1920
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: http://hdl.handle.net/10962/32480 , vital:24050
- Description: The World Economics Association held an online conference in 2012 where they published many papers on ethics in economics. The topic of ethics in economics became more serious and popular following the 2008 financial crisis. However the case for a professional code of ethics in economics is difficult to introduce and implement due to the multidisciplinary approach of the discipline. Therefore authors such as Dow (2012), De Martino (2012), Freeman (2012) and Earl (2012) urged economists to start thinking about ethics in economics from a pluralistic view. This thesis studied the effects of changing Western worldviews on morals and ethics in economics from a Protestant perspective. Numerous authoritative sources were considered and used to create a discussion and analysis of how diverse Western worldviews impact on the type of economics which is prescribed and practiced. It was found that different Western worldviews create various standards of understanding and evaluation, which result in varying opinions on what constitutes as morally or ethically acceptable within the discipline of economics.
- Full Text:
- Date Issued: 2017
Biological and geophysical feedbacks with fire in the Earth System
- Archibald, S, Lehmann, C E, Belcher, C, Bond, W J, Bradstock, R A, Daniau, A L, Dexter, K, Forrestel, E J, Greve, M, He, T, Higgins, Simon I, Ripley, Bradford S
- Authors: Archibald, S , Lehmann, C E , Belcher, C , Bond, W J , Bradstock, R A , Daniau, A L , Dexter, K , Forrestel, E J , Greve, M , He, T , Higgins, Simon I , Ripley, Bradford S
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61413 , vital:28024 , http://iopscience.iop.org/article/10.1088/1748-9326/aa9ead/meta
- Description: Roughly 3% of the Earth’s land surface burns annually, representing a critical exchange of energy and matter between the land and atmosphere via combustion. Fires range from slow smouldering peat fires, to low-intensity surface fires, to intense crown fires, depending on vegetation structure, fuel moisture, prevailing climate, and weather conditions. While the links between biogeochemistry, climate and fire are widely studied within Earth system science, these relationships are also mediated by fuels – namely plants and their litter – which are the product of evolutionary and ecological processes. Fire is a powerful selective force and, over their evolutionary history, plants across diverse clades have evolved numerous traits that either tolerate or promote fire. Here we outline a conceptual framework of how plant traits determine the flammability of ecosystems and interact with climate and weather to influence fire regimes. We explore how these evolutionary and ecological processes scale to impact biogeochemistry and Earth system processes. Finally, we outline several research challenges that, when resolved, will improve our understanding of the role of plant evolution in mediating the fire feedbacks driving Earth system processes. Understanding current patterns of fire and vegetation, as well as patterns of fire over geological time, requires research that incorporates evolutionary biology, ecology, biogeography, and the biogeosciences.
- Full Text:
- Date Issued: 2017
- Authors: Archibald, S , Lehmann, C E , Belcher, C , Bond, W J , Bradstock, R A , Daniau, A L , Dexter, K , Forrestel, E J , Greve, M , He, T , Higgins, Simon I , Ripley, Bradford S
- Date: 2017
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/61413 , vital:28024 , http://iopscience.iop.org/article/10.1088/1748-9326/aa9ead/meta
- Description: Roughly 3% of the Earth’s land surface burns annually, representing a critical exchange of energy and matter between the land and atmosphere via combustion. Fires range from slow smouldering peat fires, to low-intensity surface fires, to intense crown fires, depending on vegetation structure, fuel moisture, prevailing climate, and weather conditions. While the links between biogeochemistry, climate and fire are widely studied within Earth system science, these relationships are also mediated by fuels – namely plants and their litter – which are the product of evolutionary and ecological processes. Fire is a powerful selective force and, over their evolutionary history, plants across diverse clades have evolved numerous traits that either tolerate or promote fire. Here we outline a conceptual framework of how plant traits determine the flammability of ecosystems and interact with climate and weather to influence fire regimes. We explore how these evolutionary and ecological processes scale to impact biogeochemistry and Earth system processes. Finally, we outline several research challenges that, when resolved, will improve our understanding of the role of plant evolution in mediating the fire feedbacks driving Earth system processes. Understanding current patterns of fire and vegetation, as well as patterns of fire over geological time, requires research that incorporates evolutionary biology, ecology, biogeography, and the biogeosciences.
- Full Text:
- Date Issued: 2017
Group membership and collective action among small-scale farmers in Nkonkobe Local Municipality, Eastern Cape Province, South Africa
- Authors: Arwari, Margaret Kwamboka
- Date: 2017
- Subjects: Farmers -- South Africa -- Eastern Cape Farms, Small -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8144 , vital:31535
- Description: In South Africa, the organisation of farmers into groups has been a basic tenet for numerous, small and dispersed small-scale farmers to make their voices heard, address challenges and access support services from the government and other development agencies. However, the literature shows that the South African government promotes inappropriate forms of farmer collective action, i.e. collective production. The government seems to lack knowledge on what forms of collective action to implement and support. It is also noted in the literature that in South Africa, the majority of farmers do not participate in farmer organisations. There is limited research on the determinants of membership in farmer organisations, especially in terms of the role of ‘human agency’. Human agency is a concept which is interrelated with the concept of ‘empowerme nt’, whereby a person with strong agency is someone who is an agent of positive change. Therefore, the study sought to address these gaps. The broad objective of this study was to explore the phenomenon of group membership and collective action among small-scale farmers in Nkonkobe Local Municipality, Eastern Cape Province, South Africa. The study used the mixed method approach where an exploratory design was employed. A mult istage sampling technique was used which employed random, purposive and convenience sampling techniques. Quantitative and qualitative data were collected from 245 farmers using semistructured questionnaires and detailed qualitative data were elicited from 16 farmer organisat ions using interview guides. For the quantitative research, a cross-sectional survey design was employed. After discarded unusable observations, data from 228 farmers were analysed using a combination of descriptive statistics, simple inferential statistics, and econometric analysis. For the qualitative data obtained, thematic analysis was used in line with the study objectives. The study findings show that farmers undertake collective action through farmer organisations. These farmer organisations were categorised into two types, i.e. farmer cooperatives and farmer associations. However, low membership in these farmer organisations is noted and this was attributed to the following: (1) low farmer awareness of the existence of farmer organisations, (2) challenges faced by the organisations that contribute to their ineffectiveness and thus low membership, (3) the prevalence of negative perceptions of farmer organisations due to confusion as to their role, (4) the government’s farmer support approach which compels or encourages farmers to form groups. The results also showed that the following are determinants of participation in farmer organisations: farmer’s age, level of education, human agency, whether a farmer has off-farm income sources, whether a farmer is involved in government supported projects, whether a farmer accesses extension information, the number of visits from extension officers received by a farmer, and the number of adults in a household contributing family labour. The study findings also show that the farmers in farmer organisations have higher human agency compared to those not in farmer organisations. According to the study results, farmer groups offer a number of benefits. For one, farmer organisations are avenues for farmers’ voices to be heard, they lobby government for better access to support services such as credit, input supply, information, and training. In addition, farmers who belong to organisations experience the benefits of collective marketing. Despite the aforementioned benefits of farmer organisations, group challenges are observed. For example, farmer organisations face declining membership, the free rider problem and conflicts between members, have a problem of ineffective, old members and lack of commitment of some group members. It was therefore recommended that there is a need for concerted effort by the government, development agencies, non-governmental organisations, farmers, and farmer organisations to ensure the success of farmer organisations in promoting small-scale agriculture.
- Full Text:
- Date Issued: 2017
- Authors: Arwari, Margaret Kwamboka
- Date: 2017
- Subjects: Farmers -- South Africa -- Eastern Cape Farms, Small -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10353/8144 , vital:31535
- Description: In South Africa, the organisation of farmers into groups has been a basic tenet for numerous, small and dispersed small-scale farmers to make their voices heard, address challenges and access support services from the government and other development agencies. However, the literature shows that the South African government promotes inappropriate forms of farmer collective action, i.e. collective production. The government seems to lack knowledge on what forms of collective action to implement and support. It is also noted in the literature that in South Africa, the majority of farmers do not participate in farmer organisations. There is limited research on the determinants of membership in farmer organisations, especially in terms of the role of ‘human agency’. Human agency is a concept which is interrelated with the concept of ‘empowerme nt’, whereby a person with strong agency is someone who is an agent of positive change. Therefore, the study sought to address these gaps. The broad objective of this study was to explore the phenomenon of group membership and collective action among small-scale farmers in Nkonkobe Local Municipality, Eastern Cape Province, South Africa. The study used the mixed method approach where an exploratory design was employed. A mult istage sampling technique was used which employed random, purposive and convenience sampling techniques. Quantitative and qualitative data were collected from 245 farmers using semistructured questionnaires and detailed qualitative data were elicited from 16 farmer organisat ions using interview guides. For the quantitative research, a cross-sectional survey design was employed. After discarded unusable observations, data from 228 farmers were analysed using a combination of descriptive statistics, simple inferential statistics, and econometric analysis. For the qualitative data obtained, thematic analysis was used in line with the study objectives. The study findings show that farmers undertake collective action through farmer organisations. These farmer organisations were categorised into two types, i.e. farmer cooperatives and farmer associations. However, low membership in these farmer organisations is noted and this was attributed to the following: (1) low farmer awareness of the existence of farmer organisations, (2) challenges faced by the organisations that contribute to their ineffectiveness and thus low membership, (3) the prevalence of negative perceptions of farmer organisations due to confusion as to their role, (4) the government’s farmer support approach which compels or encourages farmers to form groups. The results also showed that the following are determinants of participation in farmer organisations: farmer’s age, level of education, human agency, whether a farmer has off-farm income sources, whether a farmer is involved in government supported projects, whether a farmer accesses extension information, the number of visits from extension officers received by a farmer, and the number of adults in a household contributing family labour. The study findings also show that the farmers in farmer organisations have higher human agency compared to those not in farmer organisations. According to the study results, farmer groups offer a number of benefits. For one, farmer organisations are avenues for farmers’ voices to be heard, they lobby government for better access to support services such as credit, input supply, information, and training. In addition, farmers who belong to organisations experience the benefits of collective marketing. Despite the aforementioned benefits of farmer organisations, group challenges are observed. For example, farmer organisations face declining membership, the free rider problem and conflicts between members, have a problem of ineffective, old members and lack of commitment of some group members. It was therefore recommended that there is a need for concerted effort by the government, development agencies, non-governmental organisations, farmers, and farmer organisations to ensure the success of farmer organisations in promoting small-scale agriculture.
- Full Text:
- Date Issued: 2017
I want to believe there is a girl here under the table
- Authors: Asfour, Fouad-Martin
- Date: 2017
- Subjects: Creative writing (Higher education) South Africa , South African fiction (English) 21st century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7190 , vital:21227
- Description: Written in non-linear fragments, my thesis is what Audre Lorde in her novel Zami calls a "biomythography" - the weaving together of myth, history and biography in epic narrative form, a style of composition that represents all the ways in which we perceive the world. Using repetition and shifting memories, I draw from my bicultural upbringing in Offenbach, a city in Germany populated mostly by migrants, as well as my experience of working in art and culture internationally, travelling and living in different countries. Interrogating objects, buildings, family photographs, books and movies, and listening to the silences of the unvoiced, I upset and play with experiences of othering, assumptions and expectations about identity and ask questions about home, belonging and migration, mother tongue and translation. I draw inspiration from Korean American artist Theresa Hak Kyung Cha's use of texts, documents and images to explore dislocation and memory, as well as authors who engage language, translation and belonging such as Mikhail Shishkin, Yoko Tawada, Gloria Anzaldua and Mohammed Khair-Eddine.
- Full Text:
- Date Issued: 2017
- Authors: Asfour, Fouad-Martin
- Date: 2017
- Subjects: Creative writing (Higher education) South Africa , South African fiction (English) 21st century
- Language: English
- Type: Thesis , Masters , MA
- Identifier: http://hdl.handle.net/10962/7190 , vital:21227
- Description: Written in non-linear fragments, my thesis is what Audre Lorde in her novel Zami calls a "biomythography" - the weaving together of myth, history and biography in epic narrative form, a style of composition that represents all the ways in which we perceive the world. Using repetition and shifting memories, I draw from my bicultural upbringing in Offenbach, a city in Germany populated mostly by migrants, as well as my experience of working in art and culture internationally, travelling and living in different countries. Interrogating objects, buildings, family photographs, books and movies, and listening to the silences of the unvoiced, I upset and play with experiences of othering, assumptions and expectations about identity and ask questions about home, belonging and migration, mother tongue and translation. I draw inspiration from Korean American artist Theresa Hak Kyung Cha's use of texts, documents and images to explore dislocation and memory, as well as authors who engage language, translation and belonging such as Mikhail Shishkin, Yoko Tawada, Gloria Anzaldua and Mohammed Khair-Eddine.
- Full Text:
- Date Issued: 2017
An intervention on how using easily accessible resources to carry out hands-on practical activities in science influences science teachers’ conceptual development and dispositions
- Authors: Asheela, Eva Ndagwedha
- Date: 2017
- Subjects: Science teachers -- In-service training -- Namibia , Science teachers -- Namibia -- Case studies , Science -- Study and teaching -- Activity programs -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/8330 , vital:21385
- Description: The reform and transformation of education systems in terms of enhancing Science, Technology Engineering and Mathematics (STEM) education in the schooling systems is gaining momentum in different parts of the world. It is argued that there is a need to enhance science education, particularly in Africa, because science education is considered to be the main vehicle through which the greater objectives such as national development and improvement in the quality of life can be realised. Namibia as a country is no exception. A key way through which science education can be enhanced is through carrying out practical activities during teaching and learning. Despite the crucial role that practical activities play in science subjects, it appears that they are not carried out in most of the Namibian science classrooms. It is against this background that this study explored an intervention on how easily accessible resources to carry out hands-on practical activities in science, influenced science teachers’ conceptual development and dispositions towards the use of practical activities in science. In this study, a mixed methods case study approach underpinned by an interpretive paradigm was adopted. The research was conducted with 21 in-service science teachers from schools in Namibia who were all on a two year part-time BEd (Honours) program delivered in Namibia by a South African university from the Eastern Cape. To generate data, document analysis, questionnaires, semi-structured interviews, an intervention in the form of workshops on practical activities, lesson observations, which were videotaped, as well as teacher reflections were used. Conceptual development, disposition and professional development served as the conceptual lenses. Vygotsky’s sociocultural theory in conjunction with Shulman’s pedagogical content knowledge (PCK) were the theoretical frameworks adopted in the study.The findings showed that there was a general perception among the participants before the intervention that in order to carry out practical activities, well-equipped laboratories, conventional chemicals and equipment are needed. Some teachers had never used practical activities in their science classes with a range of constraints or hindrances provided as reasons. The findings additionally showed that for teachers to use easily accessible resources to carry out practical activities in their science classrooms, they need the knowledge and exposure on how to use these resources. The findings thus showed that this professional development approach raised motivation, knowledge and the skills of the science teacher participants to include practical activities in their science lessons using easily accessible resources. A recommendation is that if teachers are given opportunities, through professional development platforms to engage in hands- on practical activities using easily accessible resources, they can be enabled and motivated to implement these in their science classrooms.
- Full Text:
- Date Issued: 2017
- Authors: Asheela, Eva Ndagwedha
- Date: 2017
- Subjects: Science teachers -- In-service training -- Namibia , Science teachers -- Namibia -- Case studies , Science -- Study and teaching -- Activity programs -- Namibia
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: http://hdl.handle.net/10962/8330 , vital:21385
- Description: The reform and transformation of education systems in terms of enhancing Science, Technology Engineering and Mathematics (STEM) education in the schooling systems is gaining momentum in different parts of the world. It is argued that there is a need to enhance science education, particularly in Africa, because science education is considered to be the main vehicle through which the greater objectives such as national development and improvement in the quality of life can be realised. Namibia as a country is no exception. A key way through which science education can be enhanced is through carrying out practical activities during teaching and learning. Despite the crucial role that practical activities play in science subjects, it appears that they are not carried out in most of the Namibian science classrooms. It is against this background that this study explored an intervention on how easily accessible resources to carry out hands-on practical activities in science, influenced science teachers’ conceptual development and dispositions towards the use of practical activities in science. In this study, a mixed methods case study approach underpinned by an interpretive paradigm was adopted. The research was conducted with 21 in-service science teachers from schools in Namibia who were all on a two year part-time BEd (Honours) program delivered in Namibia by a South African university from the Eastern Cape. To generate data, document analysis, questionnaires, semi-structured interviews, an intervention in the form of workshops on practical activities, lesson observations, which were videotaped, as well as teacher reflections were used. Conceptual development, disposition and professional development served as the conceptual lenses. Vygotsky’s sociocultural theory in conjunction with Shulman’s pedagogical content knowledge (PCK) were the theoretical frameworks adopted in the study.The findings showed that there was a general perception among the participants before the intervention that in order to carry out practical activities, well-equipped laboratories, conventional chemicals and equipment are needed. Some teachers had never used practical activities in their science classes with a range of constraints or hindrances provided as reasons. The findings additionally showed that for teachers to use easily accessible resources to carry out practical activities in their science classrooms, they need the knowledge and exposure on how to use these resources. The findings thus showed that this professional development approach raised motivation, knowledge and the skills of the science teacher participants to include practical activities in their science lessons using easily accessible resources. A recommendation is that if teachers are given opportunities, through professional development platforms to engage in hands- on practical activities using easily accessible resources, they can be enabled and motivated to implement these in their science classrooms.
- Full Text:
- Date Issued: 2017
Marine resource management and conservation in the Anthropocene
- Aswani, Shankar, Basurto, Xavier, Ferse, Sebastian, Glaser, Marion, Campbell, Lisa, Cinner, Joshua E, Dalton, Tracey, Jenkins, Lekelia D, Miller, Marc L, Pollnac, Richard, McGill University, Christie, Patrick
- Authors: Aswani, Shankar , Basurto, Xavier , Ferse, Sebastian , Glaser, Marion , Campbell, Lisa , Cinner, Joshua E , Dalton, Tracey , Jenkins, Lekelia D , Miller, Marc L , Pollnac, Richard , McGill University , Christie, Patrick
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124987 , vital:35716 , https://doi.10.1017/S0376892917000431
- Description: Because the Anthropocene by definition is an epoch during which environmental change is largely anthropogenic and driven by social, economic, psychological and political forces, environmental social scientists can effectively analyse human behaviour and knowledge systems in this context. In this subject review, we summarize key ways in which the environmental social sciences can better inform fisheries management policy and practice and marine conservation in the Anthropocene. We argue that environmental social scientists are particularly well positioned to synergize research to fill the gaps between: (1) local behaviours/needs/worldviews and marine resource management and biological conservation concerns; and (2) large-scale drivers of planetary environmental change (globalization, affluence, technological change, etc.) and local cognitive, socioeconomic, cultural and historical processes that shape human behaviour in the marine environment. To illustrate this, we synthesize the roles of various environmental social science disciplines in better understanding the interaction between humans and tropical marine ecosystems in developing nations where issues arising from human–coastal interactions are particularly pronounced. We focus on: (1) the application of the environmental social sciences in marine resource management and conservation; (2) the development of ‘new’ socially equitable marine conservation; (3) repopulating the seascape; (4) incorporating multi-scale dynamics of marine social–ecological systems; and (5) envisioning the future of marine resource management and conservation for producing policies and projects for comprehensive and successful resource management and conservation in the Anthropocene.
- Full Text:
- Date Issued: 2018
- Authors: Aswani, Shankar , Basurto, Xavier , Ferse, Sebastian , Glaser, Marion , Campbell, Lisa , Cinner, Joshua E , Dalton, Tracey , Jenkins, Lekelia D , Miller, Marc L , Pollnac, Richard , McGill University , Christie, Patrick
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124987 , vital:35716 , https://doi.10.1017/S0376892917000431
- Description: Because the Anthropocene by definition is an epoch during which environmental change is largely anthropogenic and driven by social, economic, psychological and political forces, environmental social scientists can effectively analyse human behaviour and knowledge systems in this context. In this subject review, we summarize key ways in which the environmental social sciences can better inform fisheries management policy and practice and marine conservation in the Anthropocene. We argue that environmental social scientists are particularly well positioned to synergize research to fill the gaps between: (1) local behaviours/needs/worldviews and marine resource management and biological conservation concerns; and (2) large-scale drivers of planetary environmental change (globalization, affluence, technological change, etc.) and local cognitive, socioeconomic, cultural and historical processes that shape human behaviour in the marine environment. To illustrate this, we synthesize the roles of various environmental social science disciplines in better understanding the interaction between humans and tropical marine ecosystems in developing nations where issues arising from human–coastal interactions are particularly pronounced. We focus on: (1) the application of the environmental social sciences in marine resource management and conservation; (2) the development of ‘new’ socially equitable marine conservation; (3) repopulating the seascape; (4) incorporating multi-scale dynamics of marine social–ecological systems; and (5) envisioning the future of marine resource management and conservation for producing policies and projects for comprehensive and successful resource management and conservation in the Anthropocene.
- Full Text:
- Date Issued: 2018
Customary management as TURFs: social challenges and opportunities
- Authors: Aswani, Shankar
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145403 , vital:38435 , DOI: 10.5343/bms.2015.1084
- Description: There is a growing interest in working with customary management (CM) systems to effectively manage benthic resources and small-scale fisheries. The underlying notion is that CM institution as territorial use rights in fisheries (TURFs) can be sufficiently adaptive and dynamic to create the local incentives that are necessary for promoting sustainable fishing practices and marine conservation more generally in a given region. This paper reviews the social opportunities and challenges of working with CM systems as a form of TURF, particularly in Oceania. A key conclusion is that policy makers and managers not only need to recognize natural interconnectivity in any one marine space, but also consider the social interconnectivity of stakeholders that covers customary TURFs. Only by recognizing and working with the existing social networks that overlay any given marine territory can the operational principles of CM (as reviewed in this paper) be effectively deployed for achieving some kind of bioeconomic efficiency and creating an equitable rights-based fisheries management system.
- Full Text:
- Date Issued: 2017
- Authors: Aswani, Shankar
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145403 , vital:38435 , DOI: 10.5343/bms.2015.1084
- Description: There is a growing interest in working with customary management (CM) systems to effectively manage benthic resources and small-scale fisheries. The underlying notion is that CM institution as territorial use rights in fisheries (TURFs) can be sufficiently adaptive and dynamic to create the local incentives that are necessary for promoting sustainable fishing practices and marine conservation more generally in a given region. This paper reviews the social opportunities and challenges of working with CM systems as a form of TURF, particularly in Oceania. A key conclusion is that policy makers and managers not only need to recognize natural interconnectivity in any one marine space, but also consider the social interconnectivity of stakeholders that covers customary TURFs. Only by recognizing and working with the existing social networks that overlay any given marine territory can the operational principles of CM (as reviewed in this paper) be effectively deployed for achieving some kind of bioeconomic efficiency and creating an equitable rights-based fisheries management system.
- Full Text:
- Date Issued: 2017
One size does not fit all: critical insights for effective community-based resource management in Melanesia
- Aswani, Shankar, Albert, Simon, Love, Mark
- Authors: Aswani, Shankar , Albert, Simon , Love, Mark
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145392 , vital:38434 , DOI: 10.1016/j.marpol.2017.03.041
- Description: In recent years, Fiji's approach of combining traditional systems of community-based coastal management and modern management systems has become a successful blueprint for marine conservation, particularly the Locally Managed Marine Area (LMMA) network model. As a result of this success, conservation practitioners have imported the Fiji LMMA model to the Solomon Islands and in Vanuatu in hope of replicating the purported success attained in Fiji. This paper argues that because tenure systems and associated political systems in Fiji, the Solomon Islands, and Vanuatu are substantially different, one cannot simply extrapolate the more centralized tenurial and political Fiji model to the decentralized tenurial and politically eclectic Solomons and Vanuatu. This paper provides an analysis of some of the various approaches used in these countries to make a case for why socio-political diversity and historical particulars matter to resource management and conservation-in-practice (and for any development interventions).
- Full Text:
- Date Issued: 2017
- Authors: Aswani, Shankar , Albert, Simon , Love, Mark
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/145392 , vital:38434 , DOI: 10.1016/j.marpol.2017.03.041
- Description: In recent years, Fiji's approach of combining traditional systems of community-based coastal management and modern management systems has become a successful blueprint for marine conservation, particularly the Locally Managed Marine Area (LMMA) network model. As a result of this success, conservation practitioners have imported the Fiji LMMA model to the Solomon Islands and in Vanuatu in hope of replicating the purported success attained in Fiji. This paper argues that because tenure systems and associated political systems in Fiji, the Solomon Islands, and Vanuatu are substantially different, one cannot simply extrapolate the more centralized tenurial and political Fiji model to the decentralized tenurial and politically eclectic Solomons and Vanuatu. This paper provides an analysis of some of the various approaches used in these countries to make a case for why socio-political diversity and historical particulars matter to resource management and conservation-in-practice (and for any development interventions).
- Full Text:
- Date Issued: 2017
Environmental and social recovery asymmetries to large-scale disturbances in small island communities
- Aswani, Shankar, Van Putten, Ingrid, Miñarro, Sara
- Authors: Aswani, Shankar , Van Putten, Ingrid , Miñarro, Sara
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67325 , vital:29073 , https://doi.org/10.1007/s11069-016-2685-2
- Description: publisher version , People’s livelihoods in tropical small-island developing states are greatly dependent on marine ecosystem services. Yet services such as fisheries and coastal buffering are being degraded at an alarming rate, thus making people increasing vulnerable to protracted and sudden environmental changes. In the context of the occurrences of extreme events such as earthquakes and tsunamis, it is vital to uncover the processes that make people in these island states resilient, or not, to environmental disruptions. This paper compares people’s perceptions of social and environmental impacts after an extreme event in the Western Solomon Islands (11 different villages on 8 different islands) to better understand how knowledge systems influence the coupling of human and natural systems. We examine the factors that contributed to perceptions of respective recovery in the environmental versus the social domains across communities with different traditional governance and modernization characteristics in a tsunami impact gradient. First, we separately assessed, at the community and individual level, the potential determinants of perceived recovery in the environmental and social domains. At the community level, the average values of the perceived environmental and social recovery were calculated for each community (1 year after the tsunami), and at the individual level, normally distributed environmental and social recovery variables (based on the difference in perceptions immediately and 1 year after the tsunami) were used as dependent variables in two General Linear Models. Results suggest that environmental and social resilience are not always coupled correspondingly and, less unexpectedly, that asymmetries during recovery can occur as a result of the underlying social and ecological context and existing adaptive capacity. More generally, the study shows how by evaluating post-disturbance perceptional data in tsunami-affected communities, we can better understand how subjective perceptions of change can affect the (de)-coupling of human and natural systems.
- Full Text: false
- Date Issued: 2017
- Authors: Aswani, Shankar , Van Putten, Ingrid , Miñarro, Sara
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67325 , vital:29073 , https://doi.org/10.1007/s11069-016-2685-2
- Description: publisher version , People’s livelihoods in tropical small-island developing states are greatly dependent on marine ecosystem services. Yet services such as fisheries and coastal buffering are being degraded at an alarming rate, thus making people increasing vulnerable to protracted and sudden environmental changes. In the context of the occurrences of extreme events such as earthquakes and tsunamis, it is vital to uncover the processes that make people in these island states resilient, or not, to environmental disruptions. This paper compares people’s perceptions of social and environmental impacts after an extreme event in the Western Solomon Islands (11 different villages on 8 different islands) to better understand how knowledge systems influence the coupling of human and natural systems. We examine the factors that contributed to perceptions of respective recovery in the environmental versus the social domains across communities with different traditional governance and modernization characteristics in a tsunami impact gradient. First, we separately assessed, at the community and individual level, the potential determinants of perceived recovery in the environmental and social domains. At the community level, the average values of the perceived environmental and social recovery were calculated for each community (1 year after the tsunami), and at the individual level, normally distributed environmental and social recovery variables (based on the difference in perceptions immediately and 1 year after the tsunami) were used as dependent variables in two General Linear Models. Results suggest that environmental and social resilience are not always coupled correspondingly and, less unexpectedly, that asymmetries during recovery can occur as a result of the underlying social and ecological context and existing adaptive capacity. More generally, the study shows how by evaluating post-disturbance perceptional data in tsunami-affected communities, we can better understand how subjective perceptions of change can affect the (de)-coupling of human and natural systems.
- Full Text: false
- Date Issued: 2017
One size does not fit all: Critical insights for effective community-based resource management in Melanesia
- Aswani, Shankar, Albert, Simon, Love, Mark
- Authors: Aswani, Shankar , Albert, Simon , Love, Mark
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/420459 , vital:71745 , xlink:href="http://dx.doi.org/10.1016/j.marpol.2017.03.041"
- Description: In recent years, Fiji's approach of combining traditional systems of community-based coastal management and modern management systems has become a successful blueprint for marine conservation, particularly the Locally Managed Marine Area (LMMA) network model. As a result of this success, conservation practitioners have imported the Fiji LMMA model to the Solomon Islands and in Vanuatu in hope of replicating the purported success attained in Fiji. This paper argues that because tenure systems and associated political systems in Fiji, the Solomon Islands, and Vanuatu are substantially different, one cannot simply extrapolate the more centralized tenurial and political Fiji model to the decentralized tenurial and politically eclectic Solomons and Vanuatu. This paper provides an analysis of some of the various approaches used in these countries to make a case for why socio-political diversity and historical particulars matter to resource management and conservation-in-practice (and for any development interventions). By examining examples of various nested and polycentric governance approaches—family, community, tribal, confederations, local community-based organizations (CBOs), and Church—it elucidate not only some of the differences between Fiji and Solomon Islands/Vanuatu, but also between Vanuatu and the Solomon Islands. This provides critical insights into some of the myriad of factors impinging on conservation aspirations in these countries and may offer some alternative ways forward not currently considered by conservation practitioners. Finally, the paper provides some guidelines to how to increase the long-term success of marine conservation programs for fisheries management and community-based management initiatives in the region.
- Full Text:
- Date Issued: 2017
- Authors: Aswani, Shankar , Albert, Simon , Love, Mark
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/420459 , vital:71745 , xlink:href="http://dx.doi.org/10.1016/j.marpol.2017.03.041"
- Description: In recent years, Fiji's approach of combining traditional systems of community-based coastal management and modern management systems has become a successful blueprint for marine conservation, particularly the Locally Managed Marine Area (LMMA) network model. As a result of this success, conservation practitioners have imported the Fiji LMMA model to the Solomon Islands and in Vanuatu in hope of replicating the purported success attained in Fiji. This paper argues that because tenure systems and associated political systems in Fiji, the Solomon Islands, and Vanuatu are substantially different, one cannot simply extrapolate the more centralized tenurial and political Fiji model to the decentralized tenurial and politically eclectic Solomons and Vanuatu. This paper provides an analysis of some of the various approaches used in these countries to make a case for why socio-political diversity and historical particulars matter to resource management and conservation-in-practice (and for any development interventions). By examining examples of various nested and polycentric governance approaches—family, community, tribal, confederations, local community-based organizations (CBOs), and Church—it elucidate not only some of the differences between Fiji and Solomon Islands/Vanuatu, but also between Vanuatu and the Solomon Islands. This provides critical insights into some of the myriad of factors impinging on conservation aspirations in these countries and may offer some alternative ways forward not currently considered by conservation practitioners. Finally, the paper provides some guidelines to how to increase the long-term success of marine conservation programs for fisheries management and community-based management initiatives in the region.
- Full Text:
- Date Issued: 2017
Environmental and social recovery asymmetries to large-scale disturbances in small island communities
- Aswani, Shankar, van Putten, Ingrid, Miñarro, Sara
- Authors: Aswani, Shankar , van Putten, Ingrid , Miñarro, Sara
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/420428 , vital:71743 , xlink:href="https://doi.org/10.1007/s11069-016-2685-2"
- Description: People’s livelihoods in tropical small-island developing states are greatly dependent on marine ecosystem services. Yet services such as fisheries and coastal buffering are being degraded at an alarming rate, thus making people increasing vulnerable to protracted and sudden environmental changes. In the context of the occurrences of extreme events such as earthquakes and tsunamis, it is vital to uncover the processes that make people in these island states resilient, or not, to environmental disruptions. This paper compares people’s perceptions of social and environmental impacts after an extreme event in the Western Solomon Islands (11 different villages on 8 different islands) to better understand how knowledge systems influence the coupling of human and natural systems. We examine the factors that contributed to perceptions of respective recovery in the environmental versus the social domains across communities with different traditional governance and modernization characteristics in a tsunami impact gradient. First, we separately assessed, at the community and individual level, the potential determinants of perceived recovery in the environmental and social domains. At the community level, the average values of the perceived environmental and social recovery were calculated for each community (1 year after the tsunami), and at the individual level, normally distributed environmental and social recovery variables (based on the difference in perceptions immediately and 1 year after the tsunami) were used as dependent variables in two General Linear Models. Results suggest that environmental and social resilience are not always coupled correspondingly and, less unexpectedly, that asymmetries during recovery can occur as a result of the underlying social and ecological context and existing adaptive capacity. More generally, the study shows how by evaluating post-disturbance perceptional data in tsunami-affected communities, we can better understand how subjective perceptions of change can affect the (de)-coupling of human and natural systems.
- Full Text:
- Date Issued: 2017
- Authors: Aswani, Shankar , van Putten, Ingrid , Miñarro, Sara
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/420428 , vital:71743 , xlink:href="https://doi.org/10.1007/s11069-016-2685-2"
- Description: People’s livelihoods in tropical small-island developing states are greatly dependent on marine ecosystem services. Yet services such as fisheries and coastal buffering are being degraded at an alarming rate, thus making people increasing vulnerable to protracted and sudden environmental changes. In the context of the occurrences of extreme events such as earthquakes and tsunamis, it is vital to uncover the processes that make people in these island states resilient, or not, to environmental disruptions. This paper compares people’s perceptions of social and environmental impacts after an extreme event in the Western Solomon Islands (11 different villages on 8 different islands) to better understand how knowledge systems influence the coupling of human and natural systems. We examine the factors that contributed to perceptions of respective recovery in the environmental versus the social domains across communities with different traditional governance and modernization characteristics in a tsunami impact gradient. First, we separately assessed, at the community and individual level, the potential determinants of perceived recovery in the environmental and social domains. At the community level, the average values of the perceived environmental and social recovery were calculated for each community (1 year after the tsunami), and at the individual level, normally distributed environmental and social recovery variables (based on the difference in perceptions immediately and 1 year after the tsunami) were used as dependent variables in two General Linear Models. Results suggest that environmental and social resilience are not always coupled correspondingly and, less unexpectedly, that asymmetries during recovery can occur as a result of the underlying social and ecological context and existing adaptive capacity. More generally, the study shows how by evaluating post-disturbance perceptional data in tsunami-affected communities, we can better understand how subjective perceptions of change can affect the (de)-coupling of human and natural systems.
- Full Text:
- Date Issued: 2017
Customary management as TURFs: social challenges and opportunities
- Authors: Aswani, Shankar
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/420407 , vital:71741 , "https://doi.org/10.5343/bms.2015.1084"
- Description: There is a growing interest in working with customary management (CM) systems to effectively manage benthic resources and small-scale fisheries. The underlying notion is that CM institution as territorial use rights in fisheries (TURFs) can be sufficiently adaptive and dynamic to create the local incentives that are necessary for promoting sustainable fishing practices and marine conservation more generally in a given region. This paper reviews the social opportunities and challenges of working with CM systems as a form of TURF, particularly in Oceania. A key conclusion is that policy makers and managers not only need to recognize natural interconnectivity in any one marine space, but also consider the social interconnectivity of stakeholders that covers customary TURFs. Only by recognizing and working with the existing social networks that overlay any given marine territory can the operational principles of CM (as reviewed in this paper) be effectively deployed for achieving some kind of bioeconomic efficiency and creating an equitable rights-based fisheries management system.
- Full Text:
- Date Issued: 2017
- Authors: Aswani, Shankar
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/420407 , vital:71741 , "https://doi.org/10.5343/bms.2015.1084"
- Description: There is a growing interest in working with customary management (CM) systems to effectively manage benthic resources and small-scale fisheries. The underlying notion is that CM institution as territorial use rights in fisheries (TURFs) can be sufficiently adaptive and dynamic to create the local incentives that are necessary for promoting sustainable fishing practices and marine conservation more generally in a given region. This paper reviews the social opportunities and challenges of working with CM systems as a form of TURF, particularly in Oceania. A key conclusion is that policy makers and managers not only need to recognize natural interconnectivity in any one marine space, but also consider the social interconnectivity of stakeholders that covers customary TURFs. Only by recognizing and working with the existing social networks that overlay any given marine territory can the operational principles of CM (as reviewed in this paper) be effectively deployed for achieving some kind of bioeconomic efficiency and creating an equitable rights-based fisheries management system.
- Full Text:
- Date Issued: 2017
Data compression, field of interest shaping and fast algorithms for direction-dependent deconvolution in radio interferometry
- Authors: Atemkeng, Marcellin T
- Date: 2017
- Subjects: Radio astronomy , Solar radio emission , Radio interferometers , Signal processing -- Digital techniques , Algorithms , Data compression (Computer science)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6324 , vital:21089
- Description: In radio interferometry, observed visibilities are intrinsically sampled at some interval in time and frequency. Modern interferometers are capable of producing data at very high time and frequency resolution; practical limits on storage and computation costs require that some form of data compression be imposed. The traditional form of compression is simple averaging of the visibilities over coarser time and frequency bins. This has an undesired side effect: the resulting averaged visibilities “decorrelate”, and do so differently depending on the baseline length and averaging interval. This translates into a non-trivial signature in the image domain known as “smearing”, which manifests itself as an attenuation in amplitude towards off-centre sources. With the increasing fields of view and/or longer baselines employed in modern and future instruments, the trade-off between data rate and smearing becomes increasingly unfavourable. Averaging also results in baseline length and a position-dependent point spread function (PSF). In this work, we investigate alternative approaches to low-loss data compression. We show that averaging of the visibility data can be understood as a form of convolution by a boxcar-like window function, and that by employing alternative baseline-dependent window functions a more optimal interferometer smearing response may be induced. Specifically, we can improve amplitude response over a chosen field of interest and attenuate sources outside the field of interest. The main cost of this technique is a reduction in nominal sensitivity; we investigate the smearing vs. sensitivity trade-off and show that in certain regimes a favourable compromise can be achieved. We show the application of this technique to simulated data from the Jansky Very Large Array and the European Very Long Baseline Interferometry Network. Furthermore, we show that the position-dependent PSF shape induced by averaging can be approximated using linear algebraic properties to effectively reduce the computational complexity for evaluating the PSF at each sky position. We conclude by implementing a position-dependent PSF deconvolution in an imaging and deconvolution framework. Using the Low-Frequency Array radio interferometer, we show that deconvolution with position-dependent PSFs results in higher image fidelity compared to a simple CLEAN algorithm and its derivatives.
- Full Text:
- Date Issued: 2017
- Authors: Atemkeng, Marcellin T
- Date: 2017
- Subjects: Radio astronomy , Solar radio emission , Radio interferometers , Signal processing -- Digital techniques , Algorithms , Data compression (Computer science)
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/6324 , vital:21089
- Description: In radio interferometry, observed visibilities are intrinsically sampled at some interval in time and frequency. Modern interferometers are capable of producing data at very high time and frequency resolution; practical limits on storage and computation costs require that some form of data compression be imposed. The traditional form of compression is simple averaging of the visibilities over coarser time and frequency bins. This has an undesired side effect: the resulting averaged visibilities “decorrelate”, and do so differently depending on the baseline length and averaging interval. This translates into a non-trivial signature in the image domain known as “smearing”, which manifests itself as an attenuation in amplitude towards off-centre sources. With the increasing fields of view and/or longer baselines employed in modern and future instruments, the trade-off between data rate and smearing becomes increasingly unfavourable. Averaging also results in baseline length and a position-dependent point spread function (PSF). In this work, we investigate alternative approaches to low-loss data compression. We show that averaging of the visibility data can be understood as a form of convolution by a boxcar-like window function, and that by employing alternative baseline-dependent window functions a more optimal interferometer smearing response may be induced. Specifically, we can improve amplitude response over a chosen field of interest and attenuate sources outside the field of interest. The main cost of this technique is a reduction in nominal sensitivity; we investigate the smearing vs. sensitivity trade-off and show that in certain regimes a favourable compromise can be achieved. We show the application of this technique to simulated data from the Jansky Very Large Array and the European Very Long Baseline Interferometry Network. Furthermore, we show that the position-dependent PSF shape induced by averaging can be approximated using linear algebraic properties to effectively reduce the computational complexity for evaluating the PSF at each sky position. We conclude by implementing a position-dependent PSF deconvolution in an imaging and deconvolution framework. Using the Low-Frequency Array radio interferometer, we show that deconvolution with position-dependent PSFs results in higher image fidelity compared to a simple CLEAN algorithm and its derivatives.
- Full Text:
- Date Issued: 2017