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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.
21

Critérios para análise de limites e potencialidades da sustentabilidade de fontes de energia: um estudo da cadeia produtiva das pequenas centrais hidrelétricas no Brasil

Nowakowski, Geórgia Alana Andréas 11 March 2015 (has links)
Esta pesquisa apresenta como tema de estudo as Pequenas Centrais Hidrelétricas (PCHs). O seu objetivo geral é identificar os principais limites e potencialidades da sustentabilidade da cadeia produtiva de PCHs no Brasil, ao contexto das dimensões ambiental, social, econômica e institucional. O referencial teórico contempla conceitos e questões referentes: a cadeia produtiva; a Teoria do Ator-rede; as fontes de energia renováveis, mais especificamente a hidroeletricidade; e aos fatores determinantes da competitividade. Para a identificação dos gargalos e potencialidades, foi realizado um mapeamento da estrutura da cadeia de produção das PCHs, assim como a descrição do panorama atual das PCHs no país. Em seguida, foram estudadas, de forma mais aprofundada, cinco etapas que compõem a cadeia: recurso natural; geração; transmissão; distribuição; e comercialização. Na sequência, foram utilizados cinco critérios (importância, probabilidade, temporalidade, efeito e abrangência) para classificar os fatores identificados em cada etapa. Por fim, através da multiplicação dos índices numéricos atribuídos aos critérios, foi obtido o Índice de Significância (IS. No que tange à metodologia da pesquisa, ela pode ser classificada como aplicada e exploratória. Os dados empregados são secundários e foi utilizada a técnica de análise qualitativa. Como resultado, foram identificados 20 limites e 17 potencialidades relacionadas com a cadeia produtiva das PCHs no Brasil, sendo que destes 37 itens, 8 foram enquadrados como muito significativos, segundo os critérios estabelecidos para o IS. No que se refere ao resultado principal da pesquisa, verifica-se que, apesar de existirem potencialidades significativas para o desenvolvimento das PCHs na matriz energética nacional (o potencial hidrelétrico das bacias hidrográficas, a sua capacidade de atuar como vetor de desenvolvimento regional, a consolidação dos fabricantes de turbinas e geradores, e o livre acesso), alguns gargalos existentes na sua cadeia de produção devem ser trabalhados, tais como a interferência na migração e reprodução da ictiofauna continental, a desigualdade na distribuição de energia elétrica, e os aspectos legais e técnicos relacionados com o meio ambiente e a comercialização de energia. / This research study has as a theme: Small Hydro Power Plants (SHP). Its overall objective is to identify the main limits and potential sustainabilities of the productive chain of power plants in Brazil to the context of environmental, social, economic and institutional dimensions. The theoretical framework includes concepts that concern: the production chain, the Actor-Network Theory, renewable energy sources (specifically hydroelectricity) and the determinants of competitiveness. For the identification of limits and potential, mapping of the production of SHP chain structure was carried out; as well as the description of the current landscape of the SHP in the country. They were then studied in more depth. The five steps that make up the chain being: natural resource, generation, transmission, distribution and commercialization. Next, five criteria were used: importance, likelihood, timeliness, effect and scope; in order to classify the factors identified in each step. Finally, by multiplying the numerical index assigned to the criteria; the significance index (SI) was obtained, which was used to frame the final significance of the aspects by: less significant, significant and very significant. Regarding research methodology; it can be classified as: exploratory and applied. The data used was secondary and was used as qualitative analysis. As a result, we identified 20 potential limits and 17 related to the production chain of power plants in Brazil, and of these 37 items, 8 were classified as very significant, according to the criteria established for the IS. With regard to the main search result, it appears that, although there are significant potential for the development of SHP in the national energy matrix (hydropower potential of river basins, their ability to act as regional development vector, consolidation of turbines and generators manufacturers, and free access), some hurdles in the production chain must be worked out, such as interference in the migration and reproduction of continental fish fauna, inequality in the distribution of electricity, and the legal and technical aspects related to the environment and the commercialization of energy.
22

Supportability Engineering in Wind Power Systems - Who Cares? : Considering important stakeholders and their requirements

Ciganovic, Renato January 2011 (has links)
Wind power is one of the fastest growing energy sources, which have advantages in terms of delivering clean, cheap and fast energy. Many actors and organizations have realized this potential, which has lead to exponential growth of the wind power over recent couple of years. Despite promising future of clean and green energy through wind there are still areas to be improved to tackle main hinders for further development on a larger scale. The larger scale development of wind power has up-to-date been reached in only few countries such asDenmarkandGermany. The most potential can be found through offshore wind turbines due to, among other, lesser height and noise restrictions than inland wind turbines as well as better wind resources. This thesis is mainly characterized by the mixed-method method, which is in its turn characterized by mixing different research methods such as induction, deduction and abduction as they might be suitable to apply during the different stages of the research process. In this thesis the system approach will be considered to model the scope of this study’s context. As this thesis was constructed as a theoretical study the systematic literature review was used as the main source for data collection. The synthesis of the reviewed articles was initially performed in a broad manner to show overall picture of research related to the scope of this thesis. In the following step, the adopted LCM tool was used to extract study specific data from the reviewed and additional articles. This enabled to link some of the current problems, in wind power area, and ‘unfulfilled’ stakeholder requirements.    This thesis aim was to identify important stakeholders and to address their respective requirements within the scope of supportability engineering applied in the wind power context, particularly stakeholder requirements that have not been considered by previous research. The purpose of it was to compare different requirements with current issues in the wind power sector. Conducted systematic literature review showed significant and costly (development) issues related to the supportability engineering such as reliability, availability, maintainability, accessibility problems etc. This was fully in line with the stakeholders’ requirements, which in several cases demanded higher dependability i.e. availability performance and its influencing factors.  The thesis also included definition of supportability engineering framework, through comparing several widely accepted and standardized theoretical concepts. This comparison enabled definition of more focused approach with requirements on the ‘supported system’ and to lesser extent the ‘support system’. These requirements are usually mixed within the different theoretical concepts.  The main findings from this study are that application of supportability engineering framework would lead to earlier identification of important stakeholders and their requirements. Considering these requirements, for instance availability and maintainability of the wind turbines, at earlier stages of the life cycle through better design and improved supportability infrastructure could potentially decrease amount of current problems in the wind energy sector in particular for the offshore part. Another result was that different stakeholders and their requirements were identified. Thesis contribution overall was a new ‘refined approach’ to deal with supportability issues through supportability engineering framework, whose main focus is the ‘supported system’.
23

The development of a framework for an integrated logistics support system within a high technology industry in a developing country

Lambert, Keith Richard 31 March 2008 (has links)
Competitive and high-risk environments require complex high technology systems, which need to be supported and maintained over their respective life cycles. These systems often have a significant consequence of failure, and require complex management systems to achieve their operational objectives. Significant leadership and management challenges exist, not only in South Africa, but also in other developing countries, where systems may be utilised beyond the lifespan they were designed for and are susceptible to obsolescence. This study was conducted by following a structured process; the research consisted of three stages. The first stage dealt with the research problem, including the delimitations of the study. The second stage was further divided into three phases. The first phase deconstructed the appropriate literature, which included the interpretation of numerous definitions of logistics, integrated logistics support, and the integrated logistics support elements. In addition, the research was grounded in the fields of operations management, supply chain management and integrated logistics support. The second phase focused on the deconstruction of six case studies from four different high technology complex systems. From the analysis of the first two phases followed the third phase of research, which focused on the identification of areas requiring further research. Further research was conducted by means of a questionnaire, the results of which were analysed for variable dependency and variable association. The third stage of the research included the collation and analysis of the findings of the first two stages of research. The analysis utilised the principles of Mode 2 research and design science research, whereby an ILS framework and associated grounded technological rules have been recommended. These recommendations are robust in nature, as they can be applied in the most challenging environment and circumstances as identified. Furthermore, by grounding the theory in the disciplines of operations management, supply chain management and integrated logistics support, the reliability, validity, relevance, and applicability of the study could be substantiated. This implied that the generated theoretical knowledge could be transferred to and applied in practice, and as such, an organisation can reap substantial value added benefits, and gain considerable competitive advantage in the market place by applying this developed ILS framework and associated ILS grounded technological rules. / Business Leadership / D. BL.
24

The development of a framework for an integrated logistics support system within a high technology industry in a developing country

Lambert, Keith Richard 31 March 2008 (has links)
Competitive and high-risk environments require complex high technology systems, which need to be supported and maintained over their respective life cycles. These systems often have a significant consequence of failure, and require complex management systems to achieve their operational objectives. Significant leadership and management challenges exist, not only in South Africa, but also in other developing countries, where systems may be utilised beyond the lifespan they were designed for and are susceptible to obsolescence. This study was conducted by following a structured process; the research consisted of three stages. The first stage dealt with the research problem, including the delimitations of the study. The second stage was further divided into three phases. The first phase deconstructed the appropriate literature, which included the interpretation of numerous definitions of logistics, integrated logistics support, and the integrated logistics support elements. In addition, the research was grounded in the fields of operations management, supply chain management and integrated logistics support. The second phase focused on the deconstruction of six case studies from four different high technology complex systems. From the analysis of the first two phases followed the third phase of research, which focused on the identification of areas requiring further research. Further research was conducted by means of a questionnaire, the results of which were analysed for variable dependency and variable association. The third stage of the research included the collation and analysis of the findings of the first two stages of research. The analysis utilised the principles of Mode 2 research and design science research, whereby an ILS framework and associated grounded technological rules have been recommended. These recommendations are robust in nature, as they can be applied in the most challenging environment and circumstances as identified. Furthermore, by grounding the theory in the disciplines of operations management, supply chain management and integrated logistics support, the reliability, validity, relevance, and applicability of the study could be substantiated. This implied that the generated theoretical knowledge could be transferred to and applied in practice, and as such, an organisation can reap substantial value added benefits, and gain considerable competitive advantage in the market place by applying this developed ILS framework and associated ILS grounded technological rules. / Business Leadership / D. BL.

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