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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.
211

A real options analysis and comparative cost assessment of nuclear and natural gas applications in the Athabasca oil sands

Harvey, Julia Blum, 1982- 04 January 2011 (has links)
This report offers a comparative valuation of two bitumen production technologies, using real options analysis (ROA) techniques to incorporate strategic flexibility into the investment scenario. By integrating a probabilistic cost model into a real options framework, the value of an oil recovery facility is modeled to reflect the realistic alternatives available to decision-makers, where the course of the investment can be altered as new information becomes available. This approach represents a distinct advantage to traditional discounted cash flow (DCF) estimation, which is unable to capture operational adaptability, including the ability to expand, delay, or abandon a project. The analysis focuses on the energy inputs required for the recovery of heavy oil bitumen from Alberta, Canada, and examines both natural gas and nuclear steam plants as heat sources. The ACR-1000 reactor is highlighted as a substitute for conventional natural gas-fueled means of production, in light of the recent volatility of natural gas prices and the potential for emissions compliance charges. The methodology includes a levelized cost assessment per barrel of bitumen and estimation of cost ranges for each component. A mean-reversion stochastic price model was also derived for the both natural gas and oil price. By incorporating cost ranges into a ROA framework, the benefit of retaining project flexibility is included in its valuation. Formulated as a decision tree, built-in options include the initial selection to pursue nuclear or natural gas, site selection and licensing, the ability to switch heat source in the planning stage, and the final commitment to construct. Each decision is influenced by uncertainties, including the course of bitumen and natural gas price, as well as emissions policy. By structuring the investment scenario to include these options, the overall value of the project increases by over $150 million. The ability to switch technology type allows for an assessment of the viability of nuclear steam, which becomes economically favorable given high natural gas prices or high emissions taxes. Given an initial selection of natural gas SAGD, there is a 25% probability that a switch to nuclear steam will occur, as evolving financial conditions make nuclear the optimal technology. / text
212

An autonomous long-term fast reactor system and the principal design limitations of the concept

Tsvetkova, Galina Valeryevna 30 September 2004 (has links)
The objectives of this dissertation were to find a principal domain of promising and technologically feasible reactor physics characteristics for a multi-purpose, modular-sized, lead-cooled, fast neutron spectrum reactor fueled with an advanced uranium-transuranic-nitride fuel and to determine the principal limitations for the design of an autonomous long-term multi-purpose fast reactor (ALM-FR) within the principal reactor physics characteristic domain. The objectives were accomplished by producing a conceptual design for an ALM-FR and by analysis of the potential ALM-FR performance characteristics. The ALM-FR design developed in this dissertation is based on the concept of a secure transportable autonomous reactor for hydrogen production (STAR-H2) and represents further refinement of the STAR-H2 concept towards an economical, proliferation-resistant, sustainable, multi-purpose nuclear energy system. The development of the ALM-FR design has been performed considering this reactor within the frame of the concept of a self-consistent nuclear energy system (SCNES) that satisfies virtually all of the requirements for future nuclear energy systems: efficient energy production, safety, self-feeding, non-proliferation, and radionuclide burning. The analysis takes into consideration a wide range of reactor design aspects including selection of technologically feasible fuels and structural materials, core configuration optimization, dynamics and safety of long-term operation on one fuel loading, and nuclear material non-proliferation. Plutonium and higher actinides are considered as essential components of an advanced fuel that maintains long-term operation. Flexibility of the ALM-FR with respect to fuel compositions is demonstrated acknowledging the principal limitations of the long-term burning of plutonium and higher actinides. To ensure consistency and accuracy, the modeling has been performed using state-of-the-art computer codes developed at Argonne National Laboratory. As a result of the computational analysis performed in this work, the ALM-FR design provides for the possibility of continuous operation during about 40 years on one fuel loading containing mixture of depleted uranium with plutonium and higher actinides. All reactor physics characteristics of the ALM-FR are kept within technological limits ensuring safety of ultra-long autonomous operation. The results obtained provide for identification of physical features of the ALM-FR that significantly influence flexibility of the design and its applications. The special emphasis is given to existing limitations on the utilization of higher actinides as a fuel component.
213

Strengthening the Nuclear Non-Proliferation Regime in the 21st Century: Multilateral Approaches to the Nuclear Fuel Cycle

Neame, Rebecca Beachen January 2010 (has links)
In recent years, the multilateral approach to the nuclear fuel cycle has been promoted as a potential mechanism for strengthening the nuclear non-proliferation regime. The multilateral approach has the potential to gain international favour over what has become traditional practice – the indigenous development and control of nuclear facilities. This thesis explores the way in which four states have responded to the revived attention on multilateral approaches to the nuclear fuel cycle, within the framework of the norm life cycle. The varying levels of support reflect broader international opinion on this issue, as many developing states remain concerned that they may be required to forgo not only the “inalienable right” to peaceful nuclear energy, but also the prospective economic and technological benefits of indigenous development in order to participate. However, as the risk of further proliferation and nuclear terrorism comes to the fore of international agendas, facilitating multilateral control of the most sensitive aspects of peaceful nuclear energy may be the key to strengthening the non-proliferation regime in the 21st century.
214

Technician level needs and skills development guidelines for the South African nuclear energy industry / Titus P. Mampala.

Nampala, Titus Pendukeni January 2012 (has links)
The increasing demand for electrical energy to bring about development and social change has brought about renewed interest in the use of nuclear power as one of the sources of electrical energy. The nuclear power industry has had a few decades of low activity due to previous accidents which turned the public perception against the use of nuclear as an electrical power source. The low activity has resulted in the shortage of nuclear skills as the skill previously available is now aged and about to reach retirement. The South African Government has recently announced its commitment to having nuclear in the energy mix. This will require construction of new nuclear power plants. This research arises from the need to understand whether the required human capital will be available, looking specifically at technician level in the nuclear energy industry. The main research goal of the study was to find what training and development initiatives are currently being used in industry and what needs to be in place to ensure that the industry is ready for the nuclear new-build. The researcher than proposes training and development initiatives that should be put in place to meet the demand that will be created by the nuclear new-build. / Thesis (MSc (Engineering Sciences in Nuclear Engineering))--North-West University, Potchefstroom Campus, 2013.
215

Technician level needs and skills development guidelines for the South African nuclear energy industry / Titus P. Mampala.

Nampala, Titus Pendukeni January 2012 (has links)
The increasing demand for electrical energy to bring about development and social change has brought about renewed interest in the use of nuclear power as one of the sources of electrical energy. The nuclear power industry has had a few decades of low activity due to previous accidents which turned the public perception against the use of nuclear as an electrical power source. The low activity has resulted in the shortage of nuclear skills as the skill previously available is now aged and about to reach retirement. The South African Government has recently announced its commitment to having nuclear in the energy mix. This will require construction of new nuclear power plants. This research arises from the need to understand whether the required human capital will be available, looking specifically at technician level in the nuclear energy industry. The main research goal of the study was to find what training and development initiatives are currently being used in industry and what needs to be in place to ensure that the industry is ready for the nuclear new-build. The researcher than proposes training and development initiatives that should be put in place to meet the demand that will be created by the nuclear new-build. / Thesis (MSc (Engineering Sciences in Nuclear Engineering))--North-West University, Potchefstroom Campus, 2013.
216

Divulgação científica na formação docente : construindo e divulgando conhecimento por meio do rádio e da internet

Rodrigues, Adriano Antunes January 2012 (has links)
O presente trabalho relata a implementação de um projeto de ensino, referenciado na teoria da aprendizagem significativa e no sócio-interacionismo, em uma turma de segundo módulo do curso de Licenciatura em Ciências da Natureza com Habilitação em Física do Instituto Federal de Santa Catarina. Os alunos foram engajados em um programa de produção textual para publicação de inserções radiofônicas de curta duração e na construção de um blog para a Internet sobre radioatividade e energia nuclear, tema estudado na unidade curricular de Princípios da Ciência II. Para o planejamento e construção dos textos, os alunos foram subsidiados por conteúdos sobre divulgação científica, teorias de aprendizagem, epistemologia e história da ciência, resultado da integração de outras duas unidades curriculares: Português II e Epistemologia e História das Ciências. Como material de apoio para as atividades realizadas por estes estudantes foi construído um site com textos, imagens, vídeos e mapas conceituais apresentados em aula como organizadores prévios. O objetivo do projeto consiste na compreensão dos conteúdos das unidades curriculares envolvidas e da aprendizagem significativa como referencial de ensino passível de aplicação na divulgação científica. O conteúdo dos textos produzidos pelos alunos para o rádio e para a internet, assim como os questionários aplicados antes e depois da implementação do projeto, mostraram uma apropriação de princípios e estratégias da aprendizagem significativa, dos referenciais de divulgação científica e do conhecimento científico relacionado ao tema radioatividade e energia nuclear. / This work describes the implementation, within the Instituto Federal de Educação of Santa Catarina – IFSC, of a teaching project, based on the socio-interactionism and in the meaningful learning theory, with students of the Nature Sciences major in Physics. The students engaged in a text production program to produce short-term radio broadcasts, as well as in the creation of a blog about radioactivity and nuclear energy, matter studied in the subject of Principles of Science II. In planning and in writing those texts, students relied on scientific popularization matters, learning theories, epistemology and history of science, what was a result of the integration with the Portuguese II, Epistemology, and History of Science Subjects. As a supporting material, for the activities carried out by the students, a website with texts, imagery, videos and conceptual maps presented in classes as previous organizers has been created. The project aims at the comprehension of the matters broached in the subjects involved in the course curriculum and at the meaningful learning as reference for a possible way of teaching and scientific popularization. The content of the texts produced by the students for the radio and for the Internet, as well as the questionnaires applied before and after the project development showed an appropriation of the principles and meaningful learning strategies, of the scientific popularization references and of the scientific knowledge related to the radioactivity and nuclear energy themes.
217

Mídias, mediações e a questão nuclear: uma proposta de mediação institucional e tecnológica nas aulas de Física no ensino médio

Ferreira, Marcia Alexandra Andrade 03 April 2013 (has links)
Made available in DSpace on 2016-06-02T20:02:52Z (GMT). No. of bitstreams: 1 5447.pdf: 1125898 bytes, checksum: ec38b7e797df65183e505a2977ba073a (MD5) Previous issue date: 2013-04-03 / In this paper, we defended the school's role as an institutional mediator of the media discourse. For the development of mediations, we proposed the use of traditional media and new Information and Communication Technologies (ICT) in the school environment. The need for institutional mediation of media discourse is due to the importance of the media in the formation of social representations we have about various issues, including on socio-scientific issues and also because these representations are responsible for forming our opinions. But the use of ICTs, specifically social networks of internet, is due to the importance of these new technologies in today's society and its potential for teaching, still little explored in the public schools. The social-scientific issue addressed in this paper is the nuclear issue. The choice of subject was due to his controversial aspect of public and social interest and for it has been widely reported in the media. We argue that, like all socioscientific issues, the nuclear issue should be addressed, at school, from the focus on relationships between Science, Technology, Society and Environment (STSE). We created, in internet, the social network "Thinking Physics" in order to, through the sharing of content, promote the participation of high school students from public schools in the discussion on the nuclear issue, thus contributing to the qualitative improvement of the use that young students make of social networks and to the development of technological mediations. To problematize the nuclear issue, we proposed a discussion of the agreement signed in 2010 between Brazil, Turkey and Iran, and to discuss this issue we used four videos aired by the television media and posted on YouTube. Through social networking students had access to the videos and were able to share their opinions through comments. There was broad participation of students in the social network, even though it was optional. The results show us that it is feasible to develop projects that use computers and internet even when school does not have such technology available to students and teachers. We hope this work will contribute to other teachers develop projects aimed at training students in critical and participatory, based on proposals of mediations of media discourse and thus the social networks of internet can become an effective mediation space technology. / Neste trabalho, defendemos o papel da escola como mediadora institucional do discurso midiático. Para o desenvolvimento das mediações, propusemos o uso de mídias tradicionais e de novas Tecnologias da Informação e Comunicação (TICs) no processo de educação escolar. A necessidade de mediação institucional do discurso midiático deve-se à importância da mídia na formação das Representações Sociais que temos sobre diversos assuntos, inclusive sobre temas sociocientíficos e, também, porque essas representações são responsáveis pela formação das nossas opiniões. Já o uso das TICs, mais especificamente das redes sociais da internet, deve-se à importância dessas novas tecnologias na sociedade atual e suas potencialidades para o ensino, ainda pouco exploradas na rede pública de escolas. O tema sociocientífico abordado neste trabalho é a questão nuclear. A escolha do tema se deu em virtude do seu aspecto controverso de interesse público e social. Defendemos que, assim como todos os temas sociocientíficos, a questão nuclear deve ser abordada, na escola, a partir do enfoque nas relações entre Ciência, Tecnologia, Sociedade e Ambiente (CTSA). Criamos, na internet, a rede social Pensando a Física a fim de, por meio do compartilhamento de conteúdos, promover a participação dos alunos do ensino médio de escolas públicas na discussão sobre a questão nuclear, contribuindo, desse modo, para a melhoria qualitativa dos usos que os estudantes jovens fazem das redes sociais e para o desenvolvimento de mediações tecnológicas. Para a problematização da questão nuclear, propusemos uma discussão acerca do acordo firmado, em 2010, entre Brasil, Turquia e Irã e, para discutir o assunto em questão, utilizamos quatro vídeos veiculados pela mídia televisiva e disponibilizados no YouTube. Através da rede social os alunos tiveram acesso aos vídeos e puderam compartilhar suas opiniões por meio de comentários. Houve ampla participação dos alunos na rede social, ainda que ela fosse facultativa. Os resultados obtidos mostram-nos que é viável desenvolver projetos que utilizam computadores e internet mesmo quando a escola não possui tais tecnologias à disposição dos alunos e professores. Esperamos que este trabalho contribua para que outros professores desenvolvam projetos que visem à formação de alunos críticos e participativos, a partir de propostas de mediações do discurso midiático e que, desse modo, as redes sociais da internet possam tornar-se um espaço efetivo de mediação tecnológica.
218

Estudo da responsabilidade social do Instituto de Pesquisas Energéticas e Nucleares de São Paulo (IPEN/CNEN-SP) / Study of social responsability of the Nuclear and Energy Research Institute of São Paulo (IPEN/CNEN-SP)

MUTARELLI, RITA de C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:38Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:49Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
219

Avaliação de dados nucleares para dosimetria de nêutrons / Evaluation of nuclear data for neutron dosimetry

TARDELLI, TIAGO C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:42:16Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:21Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
220

Pesquisas propriedades e aplicacoes de detectores de faisca em problemas de fisica nuclear de energia atomica

GONCALVES, JOSEMARY A.C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:37:18Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:06Z (GMT). No. of bitstreams: 1 02029.pdf: 4740189 bytes, checksum: ff05d787c5ab98b675cc36bbe2b0c062 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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