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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Agro-pastoralists turned fishermen : socio-economic and environmental changes in the buffer zone of Coiba National Park, Panama

Crête, Philippe. January 2006 (has links)
In upcoming decades, the conservation and sustainable use of coastal and marine resources will become a major political and environmental challenge, as two-thirds of the world's population lives in coastal zones. The issue will likely become more problematic in developing countries, where an important number of coastal inhabitants still rely on marginal extractive activities such as fishing, farming and cattle ranching for subsistence, and where the rural poor's demand for development often lead to unsustainable extractive practices. Thus, innovative solutions need to be developed to ensure the long-term conservation and sound management of marine and coastal resources. This Masters thesis addresses the case of Coiba National Park, a marine protected area located in the Gulf of Chiriqui, Panama, and its relationship with coastal fishing and farming communities located at its outskirt. Particularly, this thesis aims to discover the drivers that pushed an important number of coastal agro-pastoralists of Coiba National Park's buffer zone to switch to artisanal fishing over the past three decades, and to determine the social, economic, and environmental impacts that resulted from that switch. In addition, this thesis analyses the relationship between Coiba National Park's authorities and buffer zone communities, and how this relationship has evolved over the years as more and more resource-users exploit the marine resources of the park. Finally, this work analyses Coiba National Park's current management strategy, how park authorities have been able to adapt their planning and management activities over the years, and explores alternatives to improve Coiba National Park's management strategy so that it can better adapt to the ever changing social, economic, and environmental conditions in which Coiba National Park's buffer zone operates.
362

Small-scale mango farmers, transaction costs and changing agro-food markets: evidence from Vhembe and Mopani districts, Limpopo Province

Aphane, Mogau Marvin January 2011 (has links)
<p>The main objective of this study was to identify ways in which transaction costs can be lowered to improve small-scale farmers&rsquo / participation in and returns from agricultural output markets, with specific reference to small-scale mango farmers in Limpopo province. This study hypothesizes that transaction costs are lower in informal spot markets and increase when small-scale farmers sell in more structured markets (formal markets). This study builds on transaction cost economics (TCE) to demonstrate how to overcome transaction cost barriers that small-scale mango farmers face in the agro-food markets. The approach to collect primary information was sequenced in two steps: first, key informant and focus group interviews were conducted and, secondly, a structured survey instrument was administered in two districts of Limpopo. A total of 235 smallscale mango farmers were interviewed. A binary logistic regression model was used to estimate the impact of transaction costs on the likelihood of households&rsquo / participation in formal (=1) and informal (=0) agro-food markets. STATA Version 10 was used to analyse the data. This study found that a larger proportion of male than female farming households reported participation in the formal markets, suggesting deep-seated gender differentiation in market participation. The average age of small farmers participating in formal markets is 52, compared to 44 for those in informal markets, implying that older farmers might have established stronger networks and acquired experience over a longer period. Farmers staying very far from the densely populated towns (more than 50 km) participate less in the formal markets than those staying closer (0 &ndash / 25 km and 26 &ndash / 49 km), which implies that the further they are from the towns, the less the likelihood of farmers selling in the formal markets. Farmers who own storage facilities and a bakkie (transportation means) participate more in formal markets compared to those who do not own these assets, which suggests that these farmers are able to store mangoes, retaining their freshness and subsequently delivering them to various agro-food markets on time. Households that participate in formal markets have high mean values of income and social grants. However, this study found that the likelihood of a household&rsquo / s participation in the markets is less as income and social grants increase. This suggests that households do not invest their financial assets in order to overcome market access barriers. A large proportion of households that own larger pieces of arable land participate in the formal markets, which implies that they are able to produce marketable surplus. Households that have a high mean value (in Rand) of cattle participate more in formal markets than in informal markets. However, this study found that the likelihood of a household&rsquo / s participation in the markets does not change with an increase in the value of its livestock. These findings suggest that households do not sell their cattle in order to overcome market access barriers. Reduced transaction costs for small-scale mango farmers in Limpopo should improve their participation in and returns from the agro-food markets. Policy interventions to support this need to focus on: access to storage and transportation facilities, enforcement of gender equity requirements in existing policies, and better access to information about markets.</p>
363

Digital Tuft Flow Visualisation of Wind Turbine Blade Stall

Swytink-Binnema, Nigel 20 May 2015 (has links)
Wind turbines installed in the open atmosphere experience much more complex and highly-varying flow than their counterparts in wind tunnels or numerical simulations. In particular, aerodynamic stall—which occurs often on stall-regulated wind turbines in such variable flow conditions—can affect both wind turbine blade lifespan and noise generation. A field test site was therefore installed at the outer limits of the city of Waterloo, Ontario to study a small-scale 30 kW stall-regulated wind turbine. Experimental equipment was installed to monitor parameters such as wind speed and direction, electrical power output, blade pitch angle, rotor rotational speed, and wind turbine yaw orientation. Extensive hardware and software was developed and installed to wirelessly collect data from all instrumentation. Tufts and a remote-operated camera were also installed on one of the two blades of the 10 m diameter horizontal-axis turbine. In a variation on the tuft flow visualisation technique, video files were analysed using a novel digital image processing code. The code was developed in MATLAB to calculate the fraction of the blade which was stalled by determining the position and angle of each tuft in every video frame. The algorithm was able to locate on average 85% of the visible tufts and correctly tagged those which were stalled with a bias of only −5% compared to the typical manual method. When the algorithm was applied to 7 h of tuft video at the outboard 40% of the blade, the total average fraction of stalled tufts varied from 5% at 5 m/s to 40% at 21 m/s. This trend was expected for the stall-regulated design since, as the wind speed is increased, the stall progresses from inboard to outboard regions and from trailing edge to leading edge. The 7 h time period represents at least a two order-of-magnitude increase compared with time periods analysed using previous manual methods. This work has demonstrated a digital implementation of tuft flow visualisation which lends statistical validity (through long-time-period averaging) to a common tool for researching wind turbine stall. The speed and ease with which the tuft method can be implemented, combined with the high cost per energy of small-scale wind turbines, suggest that this digital algorithm is a highly beneficial tool for future studies.
364

Småskalig lagring av solcellsel : En överblick över möjligheterna att lagra solcellsel i uppladdningsbara batterier och vattenmagasin.

Steen Englund, Jessika January 2012 (has links)
I det här examensarbetet dimensioneras en solcellsanläggning med batteribank till fyra kolonistugor som kommer att vara bebodda under sommarhalvåret på Wij Trädgårdar i Ockelbo. Den förväntade elanvändningen beräknas för två olika brukarbeteenden. Ett brukarbeteende där hushållsapparater med höga effekter (exempelvis mikrovågsugn) förväntas ha kortare drifttider vilket resulterar i lägre krav på installerad solcellseffekt samt en mindre batteribank.För den kemiska energilagringen i en batteribank undersöks flera olika typer av uppladdningsbara batterier. AGM blyackumulatorn är det batteri som anses vara lämpligt för kemisk energilagring i solcellssystemet och som har använts vid dimensioneringen av batteribanken. Vidare undersöks möjligheterna att lagra elektricitet småskaligt genom pumpat vatten till ett vattenmagasin, som ett komplement till energilagringen i batteribanken. Genom ett vattenlagringssystem kan överskottselen från solcellerna användas för att pumpa upp vatten till ett vattenmagasin på en högre höjd och därmed lagras genom lägesenergi. När det finns ett behov av elektricitet och den lagrade energin i batteribanken inte är tillräcklig kan vattnet flöda genom en vattenturbin som genererar el till batteribanken och lasterna. Ett vattenlagringssystem kan skydda batteribanken från djupare urladdningar, vilket kan öka batteriernas livslängd i form av antalet laddningscykler, samt ta tillvara överskottselen från solcellerna i större utsträckning. Batteribanken står för en stor del av inköpskostnaden och det finns både miljömässiga och ekonomiskt starka incitament att hitta sätt att förlänga batteribankens livslängd. / In this bachelor thesis is the size of a battery bank and the demand of photovoltaic power to supply electricity to four off-grid cottages calculated, which are occupied during the summer months at Wij Trädgårdar in Ockelbo. The expected electricity demand of the households is calculated for two different user patterns. In one of the user patterns the household appliances with a high power demand (for example microwave) are expected to have a shorter daily usage time, which results in a considerable lower purchase cost as a result from lower power demand of installed photovoltaic and a smaller battery bank. For the battery bank have different rechargeable batteries been investigated. The AGM Lead-Acid battery is found to be the most suitable rechargeable battery for chemical energy storage in this photovoltaic system. Furthermore the possibilities of pumping water to a water reservoir and store as potential energy as a complement to the energy storage in the battery bank have been investigated and discussed. Through a small-scale pumped hydro storage the surplus electricity from the photovoltaic can be used to pump up water to a reservoir at a higher altitude and be stored as potential energy. When there is a demand of electricity and the energy stored in the battery bank is not enough the water can be used in a small-scale water turbine, which generates electricity t the battery bank and the loads. A pumped hydro storage can protect the battery bank from deeper discharge, which otherwise can reduce the lifetime of the batteries, and extend the number of charge and discharge cycles the batteries can manage. The battery bank represents a large part of the purchase costs and there are strong environmental and economical incentives to prolong the lifetime of the battery bank.
365

Non-Financial Returns of Enterprise-Led Development Assistance - A Study of Energy-Related Enterprises

Kolominskas, Chaim Unknown Date (has links)
The Rural Energy Enterprise Development (REED) initiative provides assistance to energy-related enterprises to prepare them for growth and to make eventual investments by mainstream financial partners less risky. This study assesses the non-financial returns of a number of REED-type enterprises and provides guidance for the selection and ongoing evaluation of these enterprises within the context of development interventions. This study concludes that desired development outcomes should provide the basis for programme objectives against which non-financial returns can be measured. However, qualitative information is also necessary, as the context within which an enterprise operates largely defines the importance of these returns. Further work to improve the understanding of this context is necessary prior to the development of a formalised monitoring programme. Limitations of the assessment process should be recorded and addressed through the ongoing review of the programme, other monitoring efforts and further research.
366

Capability building for the manufacture of photovoltaic system components in developing countries

Bruce, Anna Gabrielle, Photovoltaics & Renewable Energy Engineering, Faculty of Engineering, UNSW January 2007 (has links)
The manufacture of photovoltaic (PV) system components has a role to play in the industrialisation and poverty reduction strategies of developing countries. It has also been suggested that small scale local manufacture of balance of systems components has the potential to improve the maintenance, installation and use of the technology. However, PV is a complex technology and most developing countries have not been able to build the capabilities required to manufacture PV system components of an appropriate quality and price, either in the modern or small scale sectors. The factors that determine the success of PV manufacturers in developing countries are therefore of interest. Previous studies on learning in the PV industry have been focused on industry-wide concerns and have not explicitly addressed enterprise-level capability building or challenges specific to developing countries. In particular, there has been very little published about small scale PV manufacture. This thesis therefore aims to improve understanding of the factors that influence capability building, with a view to assisting decision making in relation to PV manufacture in developing countries. The aims of the study have been fulfilled by the development and assessment of a software simulation training tool for PV cell production line engineers, the development of an analysis framework, and application of it to several case study PV enterprises. Through the application of the framework to the case studies, it has been possible to assess the role of software simulations, the suitability of countries with different types of infrastructure for hosting PV manufacturing and the institutional arrangements or interventions that could be used to promote capability building for PV manufacturers in developing countries. While further case studies are required to make more than tentative conclusions, the framework developed and tested in this thesis may now be used as a tool to systematically and rapidly analyse the appropriateness of different types of PV manufacture in particular countries, to identify the weaknesses in their PV technological systems and therefore to suggest where resources should be invested and where appropriate institutional changes could be made. The simulation software has been demonstrated to be an effective capability building tool, thus providing one of the key elements required for successful manufacturing.
367

An evaluation of the effectiveness of differing levels of extension assistance in improving the adoption and management of small-scale forestry in Leyte Island, the Philippines

John Baynes Unknown Date (has links)
This thesis presents an evaluation of the effectiveness of an agroforestry extension program to smallholder farmers on Leyte Island, the Philippines. The imperative for reforestation is well recognised in the Philippines and was the impetus for this program which provided farmers with assistance to establish and silviculturally manage timber trees on their land. Because the cost-effectiveness of agroforestry extension is increased if farmers develop self-efficacy without extensive training, the extension program was offered in two regimes to test the necessity for extended assistance. In the extended assistance regime, farmers were offered on-site assistance to collect seed, grow seedlings, prepare sites and establish trees, whereas in the limited assistance regime, farmers were only offered assistance to collect seed and grow seedlings. Descriptive statistics were collected of farmers’ acceptance of technology and the manner in which technology was adapted to suit their personal circumstances. Translated conversations between farmers and extension staff also provided a rich source of data which provided insights into farmers’ motivation. Extension activities were reviewed at a mid-program workshop, a final on-site inspection and an end-of-program workshop. Farmers responded positively to the extended assistance program which helped them to grow and out-plant seedlings. The limited assistance program was relatively unsuccessful. Overall, the extension program was successful in shifting the initiative for further planting from extension staff to participating farmers. However, farmers showed little interest in applying silvicultural thinning or pruning to existing plantations of trees because extension advice was not congruent with their existing mental models of these procedures. Systems modelling of socio-economic variables which had been found to affect program outcomes was used to predict critical success factors. A key constraint to program recruitment was found to be farmers’ perception of harvest security, even when their needs for technology and planting materials are met. Modelling also cast doubt on the usefulness of written extension materials and emphasised the necessity for extended face-to-face technical assistance. Although conducted in Leyte, the findings of this research provide guidance for issues which affect the adoption of agroforestry both in the Philippines and in other countries. The research found that it was possible to recruit and motivate farmers without providing material incentives. If farmers experienced unexpected problems, providing extended face-to-face contact and assistance was critical if catastrophic losses of participating farmers were to be avoided. The failure of attempts to introduce advanced-age silviculture also indicated a need to elicit farmers’ mental models as a precursor or parallel enquiry to extension activities. In a situation where little was initially known about farmers’ understanding of agroforestry technology or the variables which affect their acceptance or rejection of extension assistance, the results of this research have shown that it is possible to build the capacity of farmers to establish timber trees. This result is in contrast to the acknowledged failure of the logging concession system in the Philippines and the difficulties faced by some industrial plantations and community-based programs. This investigation has shown that an opportunity exists to lift the level of tree planting in Leyte, provided that system variables which are either critical success factors or impediments are addressed.
368

Non-Financial Returns of Enterprise-Led Development Assistance - A Study of Energy-Related Enterprises

Kolominskas, Chaim Unknown Date (has links)
The Rural Energy Enterprise Development (REED) initiative provides assistance to energy-related enterprises to prepare them for growth and to make eventual investments by mainstream financial partners less risky. This study assesses the non-financial returns of a number of REED-type enterprises and provides guidance for the selection and ongoing evaluation of these enterprises within the context of development interventions. This study concludes that desired development outcomes should provide the basis for programme objectives against which non-financial returns can be measured. However, qualitative information is also necessary, as the context within which an enterprise operates largely defines the importance of these returns. Further work to improve the understanding of this context is necessary prior to the development of a formalised monitoring programme. Limitations of the assessment process should be recorded and addressed through the ongoing review of the programme, other monitoring efforts and further research.
369

An evaluation of the effectiveness of differing levels of extension assistance in improving the adoption and management of small-scale forestry in Leyte Island, the Philippines

John Baynes Unknown Date (has links)
This thesis presents an evaluation of the effectiveness of an agroforestry extension program to smallholder farmers on Leyte Island, the Philippines. The imperative for reforestation is well recognised in the Philippines and was the impetus for this program which provided farmers with assistance to establish and silviculturally manage timber trees on their land. Because the cost-effectiveness of agroforestry extension is increased if farmers develop self-efficacy without extensive training, the extension program was offered in two regimes to test the necessity for extended assistance. In the extended assistance regime, farmers were offered on-site assistance to collect seed, grow seedlings, prepare sites and establish trees, whereas in the limited assistance regime, farmers were only offered assistance to collect seed and grow seedlings. Descriptive statistics were collected of farmers’ acceptance of technology and the manner in which technology was adapted to suit their personal circumstances. Translated conversations between farmers and extension staff also provided a rich source of data which provided insights into farmers’ motivation. Extension activities were reviewed at a mid-program workshop, a final on-site inspection and an end-of-program workshop. Farmers responded positively to the extended assistance program which helped them to grow and out-plant seedlings. The limited assistance program was relatively unsuccessful. Overall, the extension program was successful in shifting the initiative for further planting from extension staff to participating farmers. However, farmers showed little interest in applying silvicultural thinning or pruning to existing plantations of trees because extension advice was not congruent with their existing mental models of these procedures. Systems modelling of socio-economic variables which had been found to affect program outcomes was used to predict critical success factors. A key constraint to program recruitment was found to be farmers’ perception of harvest security, even when their needs for technology and planting materials are met. Modelling also cast doubt on the usefulness of written extension materials and emphasised the necessity for extended face-to-face technical assistance. Although conducted in Leyte, the findings of this research provide guidance for issues which affect the adoption of agroforestry both in the Philippines and in other countries. The research found that it was possible to recruit and motivate farmers without providing material incentives. If farmers experienced unexpected problems, providing extended face-to-face contact and assistance was critical if catastrophic losses of participating farmers were to be avoided. The failure of attempts to introduce advanced-age silviculture also indicated a need to elicit farmers’ mental models as a precursor or parallel enquiry to extension activities. In a situation where little was initially known about farmers’ understanding of agroforestry technology or the variables which affect their acceptance or rejection of extension assistance, the results of this research have shown that it is possible to build the capacity of farmers to establish timber trees. This result is in contrast to the acknowledged failure of the logging concession system in the Philippines and the difficulties faced by some industrial plantations and community-based programs. This investigation has shown that an opportunity exists to lift the level of tree planting in Leyte, provided that system variables which are either critical success factors or impediments are addressed.
370

Capability building for the manufacture of photovoltaic system components in developing countries

Bruce, Anna Gabrielle, Photovoltaics & Renewable Energy Engineering, Faculty of Engineering, UNSW January 2007 (has links)
The manufacture of photovoltaic (PV) system components has a role to play in the industrialisation and poverty reduction strategies of developing countries. It has also been suggested that small scale local manufacture of balance of systems components has the potential to improve the maintenance, installation and use of the technology. However, PV is a complex technology and most developing countries have not been able to build the capabilities required to manufacture PV system components of an appropriate quality and price, either in the modern or small scale sectors. The factors that determine the success of PV manufacturers in developing countries are therefore of interest. Previous studies on learning in the PV industry have been focused on industry-wide concerns and have not explicitly addressed enterprise-level capability building or challenges specific to developing countries. In particular, there has been very little published about small scale PV manufacture. This thesis therefore aims to improve understanding of the factors that influence capability building, with a view to assisting decision making in relation to PV manufacture in developing countries. The aims of the study have been fulfilled by the development and assessment of a software simulation training tool for PV cell production line engineers, the development of an analysis framework, and application of it to several case study PV enterprises. Through the application of the framework to the case studies, it has been possible to assess the role of software simulations, the suitability of countries with different types of infrastructure for hosting PV manufacturing and the institutional arrangements or interventions that could be used to promote capability building for PV manufacturers in developing countries. While further case studies are required to make more than tentative conclusions, the framework developed and tested in this thesis may now be used as a tool to systematically and rapidly analyse the appropriateness of different types of PV manufacture in particular countries, to identify the weaknesses in their PV technological systems and therefore to suggest where resources should be invested and where appropriate institutional changes could be made. The simulation software has been demonstrated to be an effective capability building tool, thus providing one of the key elements required for successful manufacturing.

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