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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.
141

Impacts of primary energy constraints in the 21st century

Nel, Willem P. 25 March 2010 (has links)
D.Phil. / Global society has evolved into a complex multi-dimensional system in which it has become increasingly difficult to construct and maintain a systemic model of cause and effect. Specialisation and abstraction in the various disciplines of scientific and societal complexity has led to divergent theories of sustainability. Failure to integrate real life problems across disciplines poses a threat to modern society because the causal links between disciplines are unattended in many instances and events in one dimension could lead to catastrophic unintended consequences in another. In light of the above, this thesis contributes towards the multi-disciplinary integration of some of the most important sustainability concerns of modern society, namely Energy Security, Economic Growth and Global Warming. Analysing these real-life sustainability issues in a multi-disciplinary context leads to conclusions that are controversial in terms of established philosophical worldviews and policy trends. Firstly, the thesis establishes deterministic expectations of an imminent era of declining Energy Security resulting from the exhaustion of non-renewable fossil fuel resources, despite optimistic expectations of technology improvements in alternative energy sources such as renewable and nuclear. Secondly, the exhaustion of non-renewable fossil fuel resources imposes limits to the potential sources of anthropogenic carbon emissions that render the more pessimistic emissions cases considered in the global warming debate irrelevant. The lower level of attainable carbon emissions challenges the merits of the conventional carbon feedback cycle with the result that the predicted global warming is within acceptance limits of the contemporary global warming debate. Thirdly, the consequences of declining Energy Security on socio-economic welfare is a severe divergence from historical trends and demands the reassertion of the role of energy in human development, including Economic Growth theory. The thesis develops a novel economic growth model that treats energy as an explicit and Autonomous Factor of Production, thereby facilitating plausible predictions of future Economic Growth potential. The results challenge the sustainability of the current free-market capitalist economic system and demand strong policy responses to avoid the collapse of modern society.
142

Nuclear narratives in UK energy policy, 1955-2008 : exploring the dynamics of policy framing

Rough, Elizabeth Kate January 2012 (has links)
No description available.
143

Jaderná energetika a její budoucnost / Nuclear energy and its future

Eretová, Kamila January 2009 (has links)
This work deals with the potential of nuclear energy in general and in our country. Nuclear energy offers as almost a necessary alternative to fill growing demand for electricity in our country and the world. Increased attention is paid to the electricity market in our country, the role of nuclear energy in the Czech energy mix and the possibilities of its use in the future as an alternative to other energy sources (renewable, fossil resources), and savings and imports from abroad. The author summarizes the main benefits, but also the risk that nuclear energy brings. Does not forget the attitude of environmentalists, opponents and the public to the nuclear issue, which improves long-term, giving scope for the use of nuclear energy.
144

Jaderná energie a energetická bezpečnost EU / Nuclear energy and EU energy security

Ryzhenko, Maksym January 2011 (has links)
This diploma thesis is dedicated to the future development of nuclear energy in the EU area and its incorporation into the current EU energy policy. The work also focuses on a detailed examination of EU energy policy in terms of energy security of the Member States and throughout the text deals with the role of nuclear power as a determining factor of energy security. The work is divided into two parts - theoretical part (Chapter one) and research part (Chapter two and three). The first chapter of this thesis is devoted to current theoretical approaches to the issue of energy security. The issues of energy security are then examined in the final part of this chapter in terms of integration into the all-embracing EU energy policy. The second chapter provides an analysis of the current energy situation in the European Union as a whole and in individual Member States. All findings are applied with emphasis on the status of nuclear energy in the energy mix. The final chapter summarizes current nuclear energy trends in the EU. In addition, analysis of the opinion polls and government interventions in the field of nuclear energy are provided.
145

Persuasive Power: Rhetoric of Risk in Sustainability in the Nuclear Power Lobby

Wahlers, Kristen H. 18 May 2021 (has links)
No description available.
146

Reprezentace jaderné energetiky v médiích v období před a po havárii ve Fukušimě / Representation of nuclear power in media in the period before and after the accident in Fukušima

Podzemná, Lucie January 2014 (has links)
"Representation of nuclear energy in media in the period before and after the accident in Fukushima" This master's thesis examines media representation of nuclear energy within one year before and one year after the Fukushima Nuclear Disaster. The sample of news was selected from the print edition of the two main Czech dailies - MF Dnes and Právo. The method used in the thesis is content analysis. In the first part, some of the main theories of media studies (agenda setting, stereotypes, framing, and moral panic) and mechanisms which single news are constructed by (news values, access to news, primary defining, and gatekeeping) are introduced. In the second part, shift in both the focus of the media on the issue of nuclear energy and utilizing of the selected mechanisms of construction of the news is examined. In conclusion, the thesis identifies how the representation of the nuclear energy is constructed in the above said dailies over the period given before and after the Fukushima nuclear disaster.
147

Nutzung der Kernenergie - ein substanzieller Beitrag für eine zukunftssichere und nachhaltige Energieversorgung

Lippmann, Wolfgang 15 January 2008 (has links)
In der intensiv geführten Diskussion um eine nachhaltige Energiestrategie spielt international die Kernenergie eine zentrale Rolle. Sie wird als ein substanzieller Bestandteil in einem ausgewogenen Energiemix gesehen. Kernenergie ist sicher, zuverlässig, ressourcenschonend und CO2-frei. Fast alle technisch hoch entwickelten Länder planen bzw. realisieren den Neubau von modernen Kernkraftwerken. Die technologisch auf diesem Gebiet führenden Nationen haben sich zu einer Interessengemeinschaft zusammengeschlossen, die es sich zum Ziel gestellt hat, die Kernkraftwerke der nächsten Generation zu entwickeln. Deutschland ist noch nicht dabei. / The intensive discussion regarding a sustainable energy strategy is focused centrally on the international role of nuclear energy. Nuclear energy is considered a substantial component in a balanced energy mix. It is safe and reliable, saves resources and produces no CO2. Almost all technologically highly developed countries are planning or building new modern nuclear power stations. The technology leaders in this field have formed a pool aimed at developing nuclear power stations of the next generation. Germany has not yet joined this pool.
148

Optimization of material flow in the nuclear fuel cycle using a cyclic multi-stage production-to-inventory model

DePorter, Elden Leo 09 June 2012 (has links)
The nuclear fuel cycle is modelled as a cyclic, multi-stage production-to-inventory system. The objective is to meet a known deterministic demand for energy while minimizing acquisition, production, and inventory holding costs for all stages of the fuel cycle. The model allows for cyclic flow (feedback) of materials, material flow conversion factors at each stage, production lag times at each stage, and for escalating costs of uranium ore. It does not allow shortages to occur in inventories. The model is optimized by the application of the calculus of variations and specifically through recently developed theorems on the solution of functionals constrained by inequalities. The solution is a set of optimal cumulative production trajectories which define the stagewise production rates. Analysis of these production rates reveals the optimal nuclear fuel cycle costs and that inventories (stockpiles) occur in uranium fields, enriched uranium hexafluoride, and fabricated fuel assemblies. An analysis of the sensitivity of the model to variation in three important parameters is performed. / Ph. D.
149

Modified Transient Hot-Wire Needle Probe for Experimentally Measuring Thermal Conductivity of Molten Salts

Merritt, Brian N. 26 October 2022 (has links)
Molten salts are high-temperature heat transfer fluids intended for cooling and/or storage purposes in a variety of energy applications. The current work seeks to ultimately study the thermophysical properties of fluoride and chloride salts, which are commonly considered for use in advanced nuclear reactors. Thermophysical properties like thermal conductivity are fundamental to ensuring safe, efficient, and competitive designs for advanced commercial nuclear reactors. Measurement challenges with liquid salts such as electrical conduction, corrosion, convection, and thermal radiation have hindered traditional approaches in their attempts to accurately quantify these properties at high temperatures. Here, a needle probe is developed, which modifies principles from existing instrumental techniques in order to experimentally measure the thermal conductivity of molten salts with reduced error. An analytical heat transfer model is developed to characterize 1D radial heat flow in a multilayered cylindrical system. This includes a thin layer of salt located between the needle probe and a crucible to limit natural convection. After being validated with finite-element methods, the needle probe is used to measure the thermal conductivity of several reference liquids, whose thermophysical properties are well-established at low temperatures. These seven samples are water, sodium nitrate (molten salt), potassium nitrate (molten salt), toluene, ethanol, propylene glycol, and galinstan. The needle probe was able to accurately measure thermal conductivity between 0.40-0.66W/mK for these samples with 3.5-10% uncertainty. Three eutectic halide molten salts (presented by molar composition) were selected for high-temperature testing. These include the ternary fluorides LiF(46.5%)-NaF(11.5%)-KF(42%) and NaF(34.5%)-KF(59%)-MgF2(6.5%), as well as the binary chloride NaCl(58.2%)-KCl(41.8%). Because testing temperatures range between 500-750C, the governing model is adapted to account for radiative heat transfer through the salt sample in parallel with conductive heat transfer. Improvements to the experimental apparatus are also made. For all three salts, the needle probe accurately measured thermal conductivity between 0.490-0.849W/mK with total uncertainty generally being less than 20%. A linear fit to the data demonstrates a clear negative relationship between thermal conductivity and an increase in temperature, which agrees with theoretical and computational predictions. These results indicate that the needle probe successfully handles the assortment of measurement challenges associated with high-temperature molten salts and provides reliable data to create correlations for thermophysical property databases.
150

Risk Society, Nuclear Energy, and India's Response to the Fukushima Meltdown

Deb, Nikhilendu 17 September 2015 (has links)
No description available.

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