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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.
71

Avaliação comparativa do custeio baseado em atividades e do custeio variável: um estudo de caso no IPEN / Comparative evaluation of activity-based costing and variable costing: a case study at IPEN

Esteves, Joselfina Maria da Silva 03 May 2010 (has links)
Esta pesquisa tem por objetivo comparar os resultados obtidos com a aplicação dos métodos de Custeio Baseado em Atividades e do método de Custeio Variável em uma unidade administrativa do Governo Federal, a saber: a Instalação de Radiofarmácia do IPEN (Instituto de Pesquisas Energéticas e Nucleares), sendo esta uma unidade de produção de radiofármacos e de pesquisas. Diante da necessidade de se adotar uma visão mais econômica e gerencial da administração pública, a investigação proporcionou informações que permitem avaliar qual dos dois métodos de custeio se mostra mais adequado para a gestão de custos naquela unidade. A pesquisa realizada é de natureza exploratória, bibliográfica e estudo de caso único. Foram rastreados cerca de 80% dos custos relevantes por observação in loco de todo o processo de fabricação do gerador de tecnécio, o qual representa o principal produto em termos de quantidade produzida e faturamento. Os resultados obtidos revelam que a Margem de Contribuição do Custeio Variável de 29,12% é bastante próxima do resultado operacional de 28,86%, antes das atividades de apoio, obtido pelo ABC. Observa-se, também, que o resultado operacional do produto não se altera frente à utilização de um ou outro método de custeio. Nos dois métodos de custeio o resultado final é de 24,20%. Isto ocorre pelo fato de que a produção é sob demanda. Não há estoque de produto acabado por este ser radioativo. A pesquisa revelou, contudo, que ambos os métodos propiciam informações úteis para a gestão e otimização dos custos e dos resultados dos processos/atividades, bem como que os dois métodos no caso em questão, podem ser utilizados de forma integrada e complementar, permitindo que se utilize o melhor conteúdo informativo de ambos. / This research aims to compare the results with the application of Activity Based Costing and Variable Costing methods in an administrative unit of the Brazilian Federal Government: the Radiopharmacy Facility of IPEN (Institute for Energy and Nuclear Research), which produces radiopharmaceuticals products and develops R&D activities. Faced with the need to adopt a more economical and managerial public administration, this research has provided information to assess which of the two costing methods proves more suitable for cost management in that unit. The research is exploratory and a single-case study. We traced about 80% of material costs by observation \"in loco\" of the entire manufacturing process of technetium generator, which represents the main product in terms of production volume and revenues. The results show that the Contribution Margin Variable Costing of 29.12% is very close to the operating income of 28.86%, ahead of support activities, obtained by ABC. It is also noted that the operational result of the product does not change by using either one or another costing method. In the two costing methods the end result is 24.20%. This occurs because the production is on demand. There is no inventory of finished product because it is radioactive. The research has revealed that both methods provide useful information for the management and optimization of costs and results of processes/activities, and that the two methods, in this case, may be used in an integrated and complementary approach, enabling to use the best information content of both.
72

Anti-nuclear energy in West Germany the conflict between nuclear proponents and opponents.

Siegmann, Heinrich January 1978 (has links)
Thesis. 1978. M.S.--Massachusetts Institute of Technology. Dept. of Political Science. / MIROFICHE COPY AVAILABLE IN ARCHIVES AND DEWEY. / Bibliography: leaves 159-160. / M.S.
73

Studies in Nuclear Energy: Low Risk and Low Carbon

Ford, Michael J. 01 May 2017 (has links)
The amount of greenhouse gas emissions mitigation required to prevent the most dramatic climate change scenarios postulated in the 2014 IPCC Synthesis Report is substantial. Prior analyses have examined the potential for nuclear energy to play a role in decarbonizing the energy sector, one of the largest contributors to emissions worldwide. However, advanced, non-light water reactors, while often touted as a viable alternative for development, have languished. Large light water development projects have a repeated history of extended construction timelines, re-work delays, and significant capital risk. With few exceptions, large-scale nuclear projects have demonstrated neither affordability nor economic competitiveness, and are not well suited to nations with smaller energy grids, or to replace fossil generation in the industrial process heat sector. If nuclear power is to play a role in decarbonization, new policy and technical solutions will be needed. In this manuscript, we examine key aspects of past performance across the nuclear enterprise and explore the future potential of nuclear energy worldwide, focusing on policy and technical solutions that may be needed to move nuclear power forward as a part of a low-carbon energy future. We do so first at a high level, examining the history of nuclear power research and development in the United States, the nation that historically has led the way in the development of this generating technology. A significant portion of our analysis is focused on new developments in this technology – advanced non-light water reactors and small modular reactors. We find that while there are promising technical solutions available, improved funding and focus in research and new models of deployment may be needed if nuclear is to play a continuing or future role. We also find that in examining potential new markets for the technology, a continuing focus on institutional readiness is critical.
74

Potenciál využití jaderné energie v rozvojových zemích / The potencial of nuclear energy in developing countries

Klasová, Eva January 2011 (has links)
Affordable energy in sufficient quantities is essential for the melioration of the world and especially developing countries. Nuclear energy has the potential to provide long-term solution for growing energy consumption in an economically and environmentally sustainable manner. Problematic factors include the financial magnitude of the initial investment, the extensive requirements for technological and institutional establishment, issues related to safety and security, and the disposal of radioactive material. This thesis analyzes the position of nuclear power in the world. Based on an analysis of advantages and disadvantages of nuclear energy, it then identifies the potential for utilizing nuclear energy in emerging countries. Five developing countries, with very different starting positions, have been selected to investigate how they can secure and develop their energy requirements. The selected countries include China, Chile, Ukraine, United Arab Emirates and Bangladesh.
75

Avaliação comparativa do custeio baseado em atividades e do custeio variável: um estudo de caso no IPEN / Comparative evaluation of activity-based costing and variable costing: a case study at IPEN

Joselfina Maria da Silva Esteves 03 May 2010 (has links)
Esta pesquisa tem por objetivo comparar os resultados obtidos com a aplicação dos métodos de Custeio Baseado em Atividades e do método de Custeio Variável em uma unidade administrativa do Governo Federal, a saber: a Instalação de Radiofarmácia do IPEN (Instituto de Pesquisas Energéticas e Nucleares), sendo esta uma unidade de produção de radiofármacos e de pesquisas. Diante da necessidade de se adotar uma visão mais econômica e gerencial da administração pública, a investigação proporcionou informações que permitem avaliar qual dos dois métodos de custeio se mostra mais adequado para a gestão de custos naquela unidade. A pesquisa realizada é de natureza exploratória, bibliográfica e estudo de caso único. Foram rastreados cerca de 80% dos custos relevantes por observação in loco de todo o processo de fabricação do gerador de tecnécio, o qual representa o principal produto em termos de quantidade produzida e faturamento. Os resultados obtidos revelam que a Margem de Contribuição do Custeio Variável de 29,12% é bastante próxima do resultado operacional de 28,86%, antes das atividades de apoio, obtido pelo ABC. Observa-se, também, que o resultado operacional do produto não se altera frente à utilização de um ou outro método de custeio. Nos dois métodos de custeio o resultado final é de 24,20%. Isto ocorre pelo fato de que a produção é sob demanda. Não há estoque de produto acabado por este ser radioativo. A pesquisa revelou, contudo, que ambos os métodos propiciam informações úteis para a gestão e otimização dos custos e dos resultados dos processos/atividades, bem como que os dois métodos no caso em questão, podem ser utilizados de forma integrada e complementar, permitindo que se utilize o melhor conteúdo informativo de ambos. / This research aims to compare the results with the application of Activity Based Costing and Variable Costing methods in an administrative unit of the Brazilian Federal Government: the Radiopharmacy Facility of IPEN (Institute for Energy and Nuclear Research), which produces radiopharmaceuticals products and develops R&D activities. Faced with the need to adopt a more economical and managerial public administration, this research has provided information to assess which of the two costing methods proves more suitable for cost management in that unit. The research is exploratory and a single-case study. We traced about 80% of material costs by observation \"in loco\" of the entire manufacturing process of technetium generator, which represents the main product in terms of production volume and revenues. The results show that the Contribution Margin Variable Costing of 29.12% is very close to the operating income of 28.86%, ahead of support activities, obtained by ABC. It is also noted that the operational result of the product does not change by using either one or another costing method. In the two costing methods the end result is 24.20%. This occurs because the production is on demand. There is no inventory of finished product because it is radioactive. The research has revealed that both methods provide useful information for the management and optimization of costs and results of processes/activities, and that the two methods, in this case, may be used in an integrated and complementary approach, enabling to use the best information content of both.
76

Hydrogen embrittlement in nuclear and bearing applications : from quantum mechanics to thermokinetics and alloy design

Stopher, Miles Alexander January 2018 (has links)
Hydrogen embrittlement in ferrous and non-ferrous alloys is, and has been for over a century, a prominent issue within many sectors of industry. Despite this, the mechanisms by which hydrogen embrittlement occurs and the suitable means for its prevention are yet to be fully established. As hydrogen fuel becomes a prominent feature in modern concepts of a sustainable global energy infrastructure and nuclear power enters its renaissance, with commercially viable fusion plants on the horizon, hydrogen embrittlement is becoming an ever more pertinent issue. This has led to a considerable demand for novel alloys resistant to hydrogen embrittlement, notably within the bearings industry, where the commonly conflicting properties of high strength and hydrogen embrittlement resistance are required. This work investigates the mechanisms through which hydrogen embrittlement and irradiation damage occur in steels and nickel-based alloys respectively, with novel alloys designed for improved resistance. Through the engineering of secondary phases, optimised for helium and/or hydrogen trapping capacity, the novel alloys present the benefits of such trapping species with respect to embrittlement resistance. Such species have been studied in depth with respect to their interactions with hydrogen, establishing a novel mechanism of hydrogen embrittlement - the hydrogen enhanced dissolution and shearability of precipitates, leading to enhanced localised plasticity.
77

Advanced technological solutions to the negative perceptions of nuclear power plants

Joubert, Gideon Daniel January 2018 (has links)
Thesis (Master of Engineering in Electrical Engineering)--Cape Peninsula University of Technology, 2018. / Worldwide a movement is underway to replace the burning of limited fossil fuel reserves for power generation with a cleaner, more efficient, yet still reliable and cost-effective method. Even though renewable technologies are often among the most common proposed, they are still limited by factors such as cost when considering large scale generation. Further requirements for replacing fossil fuel generation methods include the need to provide a continuous and reliable output for base load requirements, which is difficult to guarantee when making use of renewables alone. The proposed alternative is nuclear energy, as it is a reliable and cleaner method of power generation as compared to fossil fuels, capable of providing cost effective energy in the long run. The downside to nuclear energy, however, is the negative perception and general dislike of this method of generation, especially among the public who have been around this technology since its early days of implementation. The aim of this study is, therefore, to inform and prove that nuclear technology has evolved and come a long way since its early days, by making use of advanced technological solutions to address the fears associated with this technology from many years ago. The study further aims to prove that technologies such as advanced safety systems, new generations of reactors, advanced containment structures for both reactors and waste containment, as well as new waste disposal methods, have evolved nuclear energy into a safer and cleaner alternative method of power generation. This is achieved by first considering the origin of the negative perceptions surrounding the technology, and the nuclear accidents of the past, which have greatly influenced opinions about nuclear technology even up until today. After identifying the concerns and fears surrounding nuclear energy, research was conducted concerning how the latest technologies and innovations in safety systems are used to address these concerns, and ultimately eliminate the threats where possible. With the biggest concern identified, namely a core meltdown event leading to the release of radioactive material into the environment, two simulations were conducted to illustrate the unlikelihood of such an event occurring. The purpose of these simulations was, moreover, to illustrate the complexity and reliability of the various safety systems incorporated into the design of a nuclear power plant, preventing such a feared release of radioactivity from occurring. The research also importantly revealed that the dangers and possible threats posed by nuclear technology are often grossly overestimated, as under normal operating conditions a coal power plant, in fact, releases more radiation into the environment than a nuclear power plant. Further research reveals that the feared nuclear waste, produced by the nuclear industry yet regulated and disposed of properly, is only a small fraction of the highly hazardous waste produced on an annual basis worldwide. It is also revealed that in terms of fatalities, fossil fuel generation, on average, is responsible for more deaths annually than the biggest nuclear disasters that have ever occurred. Addressing the fears and concerns surrounding nuclear technology is therefore important, as this valuable resource may otherwise remain under-appreciated and under-utilised because of the misperceptions which currently exist amongst the public. This furthermore results in the unnecessary exhaustion of fossil fuel reserves, and concomitant pollution of the environment – all due to antiquated fears surrounding nuclear power plants.
78

The Paradox of Uranium Development: A Polanyian Analysis of Social Movements Surrounding the Piñon Ridge Uranium Mill

Malin, Stephanie Ann 01 August 2011 (has links)
Renewal of nuclear energy development has been proposed as one viable solution for reducing greenhouse gas emissions and impacts of climate change. This discussion became concrete as the first uranium mill proposed since the end of the Cold War, the Piñon Ridge Uranium Mill, received state permits in January 2011 to process uranium in southwest Colorado’s Paradox Valley. Though environmental contamination from previous uranium activity caused one local community to be bulldozed to the ground, local support for renewed uranium activity emerges among local residents in communities like Nucla, Naturita, and Bedrock, Colorado. Regionally, however, a coalition of organized, oppositionbased grassroots groups fights the decision to permit the mill. Combined, these events allow social scientists a natural laboratory through which to view social repercussions of nuclear energy development. In this dissertation, I use a Polanyian theoretical framework to analyze social, political-economic, and environmental contexts of social movements surrounding PR Mill. My overarching research problem is: How might Polanyian double movement theory be applied to and made empirically testable within the social and environmental context of uranium development? I intended this analysis to inform energy policy debates regarding renewable energy. In Chapter 1, I found various forms of social dislocation lead to two divergent social movement outcomes. Economic social dislocation led to strong mill support among most local residents, according to archival, in-depth interview, and survey data. On the other hand, residents in regional communities experienced two other types of social dislocation – another kind of economic dislocation, related to concern over boombust economies, and environmental health dislocations related to uranium exposure, creating conditions for a regional movement in opposition to PR Mill. In Chapter 2, I focus on regulations and find that two divergent social movements – a support movement locally and a countermovement against the mill regionally – emerge also as a result of strong faith in regulations, regulators, and Energy Fuels countered by marked distrust in regulations, regulators, and Energy Fuels, respectively. In Chapter 3, I advance Polanyi’s double movement theory by comparing different emergent social movements surrounding uranium, showing that historically different circumstances surrounding uranium can help create conditions for divergent social movements.
79

Crisis and Policy Reformcraft : Advocacy Coalitions and Crisis-induced Change in Swedish Nuclear Energy Policy

Nohrstedt, Daniel January 2007 (has links)
<p>This dissertation consists of three interrelated essays examining the role of crisis events in Swedish nuclear energy policymaking. The study takes stock of the idea of ‘crisis exceptionalism’ raised in the literature, which postulates that crisis events provide openings for major policy change. In an effort to explain crisis-induced outcomes in Swedish nuclear energy policy, each essay explores and develops theoretical assumptions derived from the Advocacy Coalition Framework (ACF). The introduction discusses the ACF and other theoretical perspectives accentuating the role of crisis in policymaking and identifies three explanations for crisis-induced policy outcomes: minority coalition mobilization, learning, and strategic action. Essay I analyzes the nature and development of the Swedish nuclear energy subsystem. The results contradict the ACF assumption that corporatist systems nurture narrow subsystems and small advocacy coalitions, but corroborate the assumption that advocacy coalitions remain stable over time. While this analysis identifies temporary openings in policymaking venues and in the advocacy coalition structure, it is argued that these developments did not affect crisis policymaking. Essay II seeks to explain the decision to initiate a referendum on nuclear power following the 1979 Three Mile Island accident. Internal government documents and other historical records indicate that strategic considerations superseded learning as the primary explanation in this case. Essay III conducts an in-depth examination of Swedish policymaking in the aftermath of the 1986 Chernobyl accident in an effort to explain the government’s decision not to accelerate the nuclear power phaseout. Recently disclosed government documents show that minority coalition mobilization was insufficient to explain this decision. In this case, rational learning and strategic action provided a better explanation. The main theoretical contribution derived from the three essays is to posit the intensity and breadth of political conflict, strategic action, and analogical reasoning as key factors affecting the propensity for crisis-induced policy change.</p>
80

Environmental Worldview and Faith in Science as Moderators of the Relationship between Beliefs about and Attitudes toward Nuclear Energy

Carton, Adam D 07 April 2010 (has links)
Global climate change (GCC) may be the most pressing social and environmental issue of our time. The use of fossil fuels tops the list of human behaviors that contribute to GCC. Several ‘alternative’ energy sources are now being considered in an effort to mitigate GCC, including—controversially—nuclear energy. Examined here were environmental worldview and faith in science as moderators of the relationship between beliefs about and attitudes toward nuclear energy (ATNE). Participants were 272 college students who completed an on-line survey. Predictor variables were beliefs about whether nuclear energy contributes to GCC (GCC-beliefs) and to energy independence (EI-beliefs). Results indicated that environmental worldview moderated the negative relationship between GCC-beliefs and ATNE. Results implied that the effectiveness of arguments salient to the current nuclear energy debate concerning GCC have a medium effect on ATNE except when people are more ecocentric in their environmental worldviews.

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