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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.
131

政策體系與政策變遷之研究:停建核四政策個案分析 / Policy Systems and Policy Change: The Case Study of the Fourth Nuclear Power Plant Policy Discontinuity

莊文忠, Wen-Jong Juang Unknown Date (has links)
公共政策是藉由重大公共議題的討論來分析政府活動的一種研究途徑,將公共政策的過程切割成議題設定、政策規劃、政策合法化、政策執行、政策評估及政策終結等階段,雖可以獲致清晰的流程架構,但此一單向的線性思考方式,不但簡化了政策問題解決的複雜性,亦會喪失政策過程的動態本質。再者,公共政策的研究領域日益蓬勃壯大,研究途徑與方法亦漸趨多元發展,理論概念與分析架構的整合自然日趨重要,如此將有助於研究者將研究議題與經驗資料作最佳的組合。是以,本研究採取非線性的政策動態概念,對政策的演變作一有系統性的探索,在融合有關政策變遷的各種觀點後,提出「政策體系」的理論概念,建立「宏觀」的分析架構作為探索政策變遷現象的基礎。 政策體系乃是以政策過程為焦點,所有與政策性質相關的要素,都可視為政策體系的構成要素。首先,政策是在開放的體系中形成、維持、接續與終結,自環境中汲取養分同時受到環境的限制,由此觀之,外在環境因素是政策體系中不可忽略的一環。其次,討論政策體系自然不能遺漏政策本身的因素,政策乃為解決社會問題而生,沒有社會問題的存在,當然就不會有政策制定的需求,另一方面,政策本身的組構方式則是攸關問題的解決與否。再者,在民主體制中,任何的政策形成與改變都必須取得正當性的依據,只有問題的存在並不保證一定會被政府所處理,必須通過政治結構的考驗才可能有政策產出。最後,政策體系是一個互動的體系,政策參與者之間就政策方案的選擇所從事的各種行為與活動,都可能影響最後的政策產出。歸納言之,一個完整的政策體系至少應該包括幾個要素:外在環境的因素、政策本身的特性、結構性因素的作用及政策行動者的互動行為,這些要素的互動作用會導致政策的變遷。 最後,政策是政府選擇目標與工具來解決社會問題的重要活動,它不是在真空中運作,而是不斷與社會進行互動的連續性過程,這也是政策走進歷史之前會出現變遷的原因,本研究雖然提出具有規範意涵的分析政策變遷的理論架構,但是基於「真實個案是檢驗理論效度的最佳途徑」的法則,本研究以民進黨首次執政時期所推動的停建核四政策個案為例,利用文本中所建立的分析架構來詮釋此一政策變遷的過程,並在結論中整合理論與個案的研究發現,就政策體系的各個面向提出幾個有關政策變遷的假設性命題,以供後續研究之參考與檢證,進而促成政策變遷知識的深化。 / Public policy is a research approach to analyze governmental activities by discussing public issues. However, in most articles, the policy process is seen as a logical succession of steps: agenda setting, policy formulation, policy legitimation, policy implementation, policy evaluation, and policy termination. Although this progression of stages provides a clear and useful framework, it often obscures the complexities of public issues. In other words, most policies are not a process of linear development, from agenda setting to policy termination. Policy change is a common phenomenon. In this way, if we want to understand the dynamics of policy, it is helpful to take a nonlinear perspective. Policy change is used by a wide range of authors in public policy and other disciplines, but there is no consensus on what the definition of policy change is. In fact, this question has not been systematically explored until now. Policy change is not simply a label, but is an important part of the policy process. It is worth drawing more attention to this phenomenon. The aim of this study is to construct an analytical framework of policy change. Within this framework, we distinguish between different types of policy change: policy succession and policy termination, firstly. And we can find some cues from policy change, including organization, statutes, budget, personnel, and media. Secondly, we use the concept of policy system to connect with policy change. This concept contains several elements: external environment, policy attributes, institutional factor, and policy networks. These elements interact with each other to produce policy change. We use this framework to analyze policy discontinuity for the fourth nuclear power plant in 2000. Finally, policy is essentially about government. The major activity of government is seen as choosing goals and instruments to solve social problems. Policy does not exist in a vacuum; it is made in a concrete environment. We should see policy as a continuing process of social action and interaction. This is why policy may be changed before it is terminated. Finally, we provide some hypotheses and suggestions for further research at the end of this study.
132

Fotografie und atomare Katastrophe

Bürkner, Daniel 05 May 2015 (has links)
Die Dissertation setzt sich mit den fotografischen Repräsentationen der Atombombenabwürfe auf Hiroshima und Nagasaki sowie der Havarie des Kernkraftwerks Tschernobyl auseinander. Dabei werden künstlerische, dokumentarische und touristische Bilder analysiert, die sich der jeweiligen Strahlenkatastrophe oftmals erst Jahre nach dem Ereignis annehmen und ikonografische oder medial-materielle Bezüge zu ihr aufweisen. Es zeigen sich zentrale Strategien, atomare Katastrophen, seien sie militärischer oder ziviler Natur, in fotografische Bilder überzuführen. Gerade das eigentliche Unvermögen, die visuell nicht sichtbaren Strahlenemissionen oder die Komplexität der Vorgänge auf atomarer Ebene zu visualisieren, hat sich als prägend erwiesen und bestimmt als Paradigma der Unsichtbarkeit die kulturelle Rezeption der Ereignisse. Es ist dieser Umgang mit den Abstraktionspotentialen der nuklearen Technologie, die im aktuellen Spannungsfeld ökologischer, sozialer und energietechnologischer Bildpolitik ihre Relevanz stets von neuem unter Beweis stellt. / The dissertation project seeks to analyse the photographic positions that deal with the atomic bomb attacks on Hiroshima and Nagasaki and the accident of the nuclear power plant in Chernobyl. This focus includes press photographs of the events as well as artistic, documentary and touristic images that take an approach towards the disasters often years after and hereby form iconographic or material references to the events. The study reveals central strategies for photographic images of atomic catastrophes, be they of military or civil nature. It is the inability to visualize non-visible nuclear rays or the complexity of processes on an atomic level that has turned out to be crucial. This incapacity of making images, a paradigm of invisibility, substantially coins the cultural role of the events. The question of how a society deals with these abstract potentials of nuclear technology has turned out to be always anew of high relevance in regard to ecological, social and technological policies of images.
133

Application of the Stimulus-Driven Theory of Probabilistic Dynamics to the hydrogen issue in level-2 PSA. Application de la Stimulus Driven Theory of Probabilistic Dynamics (SDTPD) au risque hydrogène dans les EPS de niveau 2.

Peeters, Agnès 05 October 2007 (has links)
Les Etudes Probabilistes de Sûreté (EPS) de niveau 2 en centrale nucléaire visent à identifier les séquences d’événements pouvant correspondre à la propagation d’un accident d’un endommagement du cœur jusqu’à une perte potentielle de l’intégrité de l’enceinte, et à estimer la fréquence d’apparition des différents scénarios possibles. Ces accidents sévères dépendent non seulement de défaillances matérielles ou d’erreurs humaines, mais également de l’occurrence de phénomènes physiques, tels que des explosions vapeur ou hydrogène. La prise en compte de tels phénomènes dans le cadre booléen des arbres d’événements s’avère difficile, et les méthodologies dynamiques de réalisation des EPS sont censées fournir une manière plus cohérente d’intégrer l’évolution du processus physique dans les changements de configuration discrète de la centrale au long d’un transitoire accidentel. Cette thèse décrit l’application d’une des plus récentes approches dynamiques des EPS – la Théorie de la Dynamique Probabiliste basée sur les Stimuli (SDTPD) – à différents modèles de déflagration d'hydrogène ainsi que les développements qui ont permis cette applications et les diverses améliorations et techniques qui ont été mises en oeuvre. Level-2 Probabilistic Safety Analyses (PSA) of nuclear power plants aims to identify the possible sequences of events corresponding to an accident propagation from a core damage to a potential loss of integrity of the containment, and to assess the frequency of occurrence of the different scenarios. These so-called severe accidents depend not only on hardware failures and human errors, but also on the occurrence of physical phenomena such as e.g. steam or hydrogen explosions. Handling these phenomena in the classical Boolean framework of event trees is not convenient, and dynamic methodologies to perform PSA studies are expected to provide a more consistent way of integrating the physical process evolution with the discrete changes of plant configuration along an accidental transient. This PhD Thesis presents the application of one of the most recently proposed dynamic PSA methodologies, i.e. the Stimulus-Driven Theory of Probabilistic Dynamics (SDTPD), to several models of hydrogen explosion in the containment of a plant, as well as the developed methods and improvements.
134

Sledování dlouhodobých změn a hodnocení vývojových trendů krajinného prostředí údolí Vltavy ovlivněném výstavbou JETE / Monitoring of secular changes and evalution of trends in country around valley of the Vltava river influenced by the JETE

PALIVCOVÁ, Hana January 2008 (has links)
This work evaluates evolution changes of socio-economical structure and Territorial System of Ecological Stability (ÚSES) in Territory Zone. Territory Zone is meant nearer surround of river dam Hněvkovice, that is used for needs of technological water in JETE (nuclear power station Temelín). There can be found villages Buzkov, Dobřejovice, Hroznějovice, Jaroslavice, Jeznice, Kostelec, Litoradlice, Poněšice, Pořežany, Purkarec and Třitim. This work also solves evolution of number of population, age structure and employment from 1982 to 2001 as well as other specific development factors of this territory. The part of this work is the KES (Coefficient of the Ecological Stability) of the territory before and after the Hněvkovice dam was built. The basic characteristics of whole territory and list of historical interests is also important.
135

Intégrité des tours aéroréfrigérantes en béton armé sous sollicitations extrêmes : Vent et séisme / Integrity of reinforced concrete cooling towers under extreme loads : Wind and Earthquake

Louhi, Amine 30 November 2015 (has links)
Il est prévu d’augmenter la durée de vie des centrales nucléaires actuellement opérationnelles. Le vieillissement des structures en béton armé telles que les tours aéroréfrigérantes doit être évalué, son incidence sur la capacité portante calculée. Dans le cas de fortes dégradations, le renforcement doit être envisagé, afin d’assurer la pérennité de ces tours face aux sollicitations extrêmes telles que les tempêtes de vent et les séismes. Ce travail vise à quantifier les effets néfastes que peut générer la réduction de section des aciers induite par la corrosion, en particulier sur la capacité portante des tours dans des conditions de sollicitations extrêmes monotones ou cycliques de types vent et séisme. Ces sollicitations sont certainement les plus sévères, entrainant la structure dans le domaine non linéaire, elles sont susceptibles d’induire des endommagements de type fissuration qui dans le cas de sollicitation cycliques peuvent s’avérer néfastes. Des modélisations numériques sont proposées pour déterminer la réponse quasi-statique ou dynamique de la structure, en tenant compte des apparitions de fissures dans le béton et de leur évolution via des lois de comportement appropriées du matériau béton, ainsi que la plastification des aciers. Dans le cas d’une sollicitation sismique, dans le but de comparer les approches de modélisation du séisme et d’évaluer la robustesse des résultats, les réponses dynamiques sont évaluées par trois méthodes différentes de calcul : l’approche dynamique temporelle non linéaire, la méthode spectrale et la méthode modale temporelle. Des études paramétriques portant sur l’amortissement, les combinaisons de charges et les configurations structurales, sont aussi menées. Dans le cas d’une sollicitation de type vent, la technique de renforcement à l’aide de matériaux composite, tel que le tissu de fibres de carbone (TFC) est modélisée. Le comportement de la structure endommagée présentant un taux de corrosion avancée, est évalué dans le régime pré- et post-fissuration, comparativement à la structure intègre. La perte de capacité portante est quantifiée, un renforcement permettant de restaurer l'intégrité et donc d’augmenter la durée de vie de la structure est proposé. / The authorities have planned to increase the lifetime of currently operating nuclear power plants. The ageing of reinforced concrete structures such as cooling towers should be evaluated and its impact on the bearing capacity calculated. In the case of significant damage, the strengthening must be considered to ensure the sustainability of these towers facing the risk of storms and earthquakes becoming more and more frequent. This work aims to quantify the adverse effects that can generate concrete cracks and rebar section loss induced by corrosion, especially on the bearing capacity of nuclear power plant cooling towers under monotonic or cyclic extreme load conditions (wind and earthquake). These loads are certainly the most severe, since they take the structure into the nonlinear domain and can induce or amplify cracking damage. Numerical simulations are proposed to determine the quasi-static or dynamic response of the structure, taking into account appearance of concrete cracks and their evolution via an appropriate material concrete law and rebar's yielding. In the case of a seismic load, the responses are evaluated by three different methods; the nonlinear response history analysis (NLRHA), the response spectrum analysis and the modal response history analysis (MRHA) in order to compare the earthquake modeling approaches and to evaluate the robustness of the results. Parametric studies on damping, load combinations and structural configurations, are also performed. In the case of a wind load, the strengthening technique using composite materials, such as carbon fiber reinforced plastic (CFRP) is modeled. The behavior of the damaged structure with an advanced corrosion rate is estimated in the pre- and post-cracking regime, compared to the undamaged structure. The drop of bearing capacity is quantified, a reinforcement designed is proposed to restore the integrity and thus increase the lifetime of the structure.
136

Využití odpadní vody v EDU pro vytápění / Use of Waste Water in Nuclear Power Dukovany for Heating

Bohůn, Vojtěch January 2010 (has links)
This diploma thesis deals with various ways of energetically advantageous utilization of waste heat produced by industrial technologies. The focus of the diploma thesis is both to provide an overview of different ways and places of origin of waste heat in industrial technologies and of its possible reutilization, to suggest a concrete air heating system using waste heat and to propose a long-distance hot water pipe which supplies hot water pipe system with energy. First, technologies producing waste heat and some ways of regressing of heat in such technologies are theoretically described. Second, the equipment for transferring of heat and for adjustment of thermal energy parameters is described. A special focus is put on water supplies of the Nuclear Power Plant Dukovany and some selected parts of its secondary circuit, which is waste heat collected from. The analysis is supplemented by a calculation of theoretical quantity of waste heat. The aim of the calculation is to determine whether waste heat can be a source of energy for heating. Then, a current system of heating of three selected buildings in the area of the Nuclear Power Plant Dukovany is briefly described. Based on the gained knowledge, a project of air heating with two heat pumps type water – water, a heat receiver preparing warm service water and three recuperative units for preheating of fresh heating air is designed. The selection of main parts of the air heating is amended by a calculation of purchase costs and electric energy consumption. After that, the focus is placed on choice of type of hot water pipe – its trace is stated and an indicative estimation and a thermal-conditions calculation in the hot water pipe are made. The preliminary calculation serves as a source of information for a final project of air heating and calculation of changes of temperatures longwise the hot water pipe. The project contains also a calculation of pressure losses and an analysis of economical questions concerning hot water pipes. In conclusion, the results of project of air heating and hot water pipes are summarized.
137

民主化下台灣的社會運動外部策略研究 / The Study of External Strategy of Social Movement in Taiwan's Democratization

范碩銘, Fan,Shuo ming Unknown Date (has links)
本研究的問題意識為「為什麼國家體制有時無法成功消弭社會運動的風潮?」為了處理這個問題意識,本文採取一個「策略-關係」途徑的研究方法,並假設「社會運動若能於特定結構之下運用得宜的策略,即能持續生存發展」。因此,本研究探討台灣民主化過程之下一種特殊型態的「指向國家核心的社會運動」,分別是「反核四抗爭運動」以及「紅衫軍反貪腐倒扁運動」。 在本研究的第二章與第四章內容分別描述了這兩個特殊的社會運動興起背景以及台灣民主化的進程;而在本研究的第三章與第五章內容則分別討論這兩個社會運動採取的外部策略與策略互動。研究發現,「反核四抗爭運動」是以一種「以國家為槓桿」的外部策略;而「紅衫軍反貪腐倒扁運動」則採取一種「以大眾媒體為槓桿」的外部策略,這兩個案例在台灣民主化的不同階段之下分別成功形塑了「指向國家核心的社會運動」,共同見證了台灣民主化發展的獨特經驗,因此具有相當程度之指標性意義。 / The original research conscious of this study is” Why state machine sometimes can’t terminate social movement successfully?” In order to face this research conscious, the research adopt” strategic-relational approach”, and assume “If social movement could use suitable strategy in particular structure, the social movement could be exist and develop”. For the reason, this study wants to treat a special type of social movement, and we called social movements with “point at state core”. this study further select two social movements with “point at state core” in Taiwan’s Democratization:”Anti-fourth nuclear power plant movement” and ”Anti-corruption depose-Chen Campaign”. In Chapter 2 and chapter 4, we describe the background of social movement and democratic development in Taiwan; In Chapter 3 and chapter 5, we discuss external strategy and the interaction of the two social movement cases. This research discoveries that Anti-fourth nuclear power plant movement uses the external strategy of “as state as leverage”. On the other side, Anti-corruption depose-Chen Campaign uses the external strategy of “as mass media as leverage”. Finally, this study believes that the two social movements with “point at state core” play an important role in Taiwan’s Democratization.
138

Application of the Stimulus-Driven Theory of Probabilistic Dynamics to the hydrogen issue in level-2 PSA / Application de la Stimulus Driven Theory of Probabilistic Dynamics (SDTPD) au risque hydrogène dans les EPS de niveau 2.

Peeters, Agnes 05 October 2007 (has links)
Les Etudes Probabilistes de Sûreté (EPS) de niveau 2 en centrale nucléaire visent à identifier les séquences d’événements pouvant correspondre à la propagation d’un accident d’un endommagement du cœur jusqu’à une perte potentielle de l’intégrité de l’enceinte, et à estimer la fréquence d’apparition des différents scénarios possibles.<p>Ces accidents sévères dépendent non seulement de défaillances matérielles ou d’erreurs humaines, mais également de l’occurrence de phénomènes physiques, tels que des explosions vapeur ou hydrogène. La prise en compte de tels phénomènes dans le cadre booléen des arbres d’événements s’avère difficile, et les méthodologies dynamiques de réalisation des EPS sont censées fournir une manière plus cohérente d’intégrer l’évolution du processus physique dans les changements de configuration discrète de la centrale au long d’un transitoire accidentel.<p>Cette thèse décrit l’application d’une des plus récentes approches dynamiques des EPS – la Théorie de la Dynamique Probabiliste basée sur les Stimuli (SDTPD) – à différents modèles de déflagration d'hydrogène ainsi que les développements qui ont permis cette applications et les diverses améliorations et techniques qui ont été mises en oeuvre.<p><p>Level-2 Probabilistic Safety Analyses (PSA) of nuclear power plants aims to identify the possible sequences of events corresponding to an accident propagation from a core damage to a potential loss of integrity of the containment, and to assess the frequency of occurrence of the different scenarios.<p>These so-called severe accidents depend not only on hardware failures and human errors, but also on the occurrence of physical phenomena such as e.g. steam or hydrogen explosions. Handling these phenomena in the classical Boolean framework of event trees is not convenient, and dynamic methodologies to perform PSA studies are expected to provide a more consistent way of integrating the physical process evolution with the discrete changes of plant configuration along an accidental transient.<p>This PhD Thesis presents the application of one of the most recently proposed dynamic PSA methodologies, i.e. the Stimulus-Driven Theory of Probabilistic Dynamics (SDTPD), to several models of hydrogen explosion in the containment of a plant, as well as the developed methods and improvements.<p> / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
139

Výpočetní simulace urychlovačem řízeného jaderného reaktoru pro transmutaci vyhořelého jaderného paliva / Simulation of Accelerator Driven Nuclear Reactor for Spent Nuclear Fuel Transmutation

Jarchovský, Petr January 2015 (has links)
This master’s thesis deals with usage of burn-up (spent) nuclear fuel in nuclear power plants of next generation – accelerator driven transmutation plants which is produced in current nuclear power plants. This system could significantly reduce the volume of dangerous long-lived radioisotopes and moreover they would be able to take advantage of its great energy potential due to fast neutron spectrum. In the introduction are listed basic knowledge and aspects of spent nuclear fuel along with its reprocessing and the possibility of further use while minimizing environmental impact. As another point detailed description of accelerator driven systems is described together with its basic components. In addition this search is followed by individual chronological enumeration of projects of global significance concerning their current development. Emphasis is placed on SAD and MYRRHA projects, which are used like base for calculations. This last, computational part, deals with the creation of the geometry of subcritical transmutation reactor driven by accelerator and subsequent evaluation which assembly is the most effective for transmutation and energy purposes along with changing of target, nuclear fuel and coolant/moderator.
140

Risk-averse periodic preventive maintenance optimization

Singh, Inderjeet,1978- 21 December 2011 (has links)
We consider a class of periodic preventive maintenance (PM) optimization problems, for a single piece of equipment that deteriorates with time or use, and can be repaired upon failure, through corrective maintenance (CM). We develop analytical and simulation-based optimization models that seek an optimal periodic PM policy, which minimizes the sum of the expected total cost of PMs and the risk-averse cost of CMs, over a finite planning horizon. In the simulation-based models, we assume that both types of maintenance actions are imperfect, whereas our analytical models consider imperfect PMs with minimal CMs. The effectiveness of maintenance actions is modeled using age reduction factors. For a repairable unit of equipment, its virtual age, and not its calendar age, determines the associated failure rate. Therefore, two sets of parameters, one describing the effectiveness of maintenance actions, and the other that defines the underlying failure rate of a piece of equipment, are critical to our models. Under a given maintenance policy, the two sets of parameters and a virtual-age-based age-reduction model, completely define the failure process of a piece of equipment. In practice, the true failure rate, and exact quality of the maintenance actions, cannot be determined, and are often estimated from the equipment failure history. We use a Bayesian approach to parameter estimation, under which a random-walk-based Gibbs sampler provides posterior estimates for the parameters of interest. Our posterior estimates for a few datasets from the literature, are consistent with published results. Furthermore, our computational results successfully demonstrate that our Gibbs sampler is arguably the obvious choice over a general rejection sampling-based parameter estimation method, for this class of problems. We present a general simulation-based periodic PM optimization model, which uses the posterior estimates to simulate the number of operational equipment failures, under a given periodic PM policy. Optimal periodic PM policies, under the classical maximum likelihood (ML) and Bayesian estimates are obtained for a few datasets. Limitations of the ML approach are revealed for a dataset from the literature, in which the use of ML estimates of the parameters, in the maintenance optimization model, fails to capture a trivial optimal PM policy. Finally, we introduce a single-stage and a two-stage formulation of the risk-averse periodic PM optimization model, with imperfect PMs and minimal CMs. Such models apply to a class of complex equipment with many parts, operational failures of which are addressed by replacing or repairing a few parts, thereby not affecting the failure rate of the equipment under consideration. For general values of PM age reduction factors, we provide sufficient conditions to establish the convexity of the first and second moments of the number of failures, and the risk-averse expected total maintenance cost, over a finite planning horizon. For increasing Weibull rates and a general class of increasing and convex failure rates, we show that these convexity results are independent of the PM age reduction factors. In general, the optimal periodic PM policy under the single-stage model is no better than the optimal two-stage policy. But if PMs are assumed perfect, then we establish that the single-stage and the two-stage optimization models are equivalent. / text

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