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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.
581

國際石油問題之研究──經濟面分析 / The Economic Analysis of International Petroleum Problems

莊淑容, Chuang, Shu Jung Unknown Date (has links)
石油在20世紀不僅取代煤碳成為全球主要燃料,且是全球重要的工業原料,廣泛的影響全世界經濟活動,成為各國經濟發展最為依賴的資源。但是石油為不可再生的能源,全球分布又極不平均,世界各國為控制或爭取石油資源,長期以來不僅造成國際政治緊張情勢,影響國際外交局勢與國家發展,更凸顯石油問題的重要性。2003年以來國際油價雖持續上揚,但全球經濟成長仍然強勁,顯示其所造成的衝擊尚不若過去兩次石油危機時期嚴重,但由於全球短時間內無法擺脫對石油的依賴,且影響國際油價上漲的因素又十分複雜,因此高油價背後所隱藏的供給、需求問題,成為值得深入探討的議題。   有鑒於國際石油問題的對經濟及永續發展有其重要性,本文以經濟面觀點,針對國際石油供給、需求、及相關問題進行分析。本研究主要發現為,全球石油蘊藏有限且供給不穩定,在全球石油需求將繼續增加的趨勢下,追求石油安全成為石油消費國家的重要政策;而經濟能源供需情形與產業結構上的差異,是造成2003年以來高油價與1970年代石油危機不同程度經濟衝擊的主要原因,且高油價對於全球各地區經濟產生不同程度的影響;如何因應21世紀高油價時代,以及當代面臨石油使用所造成的全球氣候暖化問題,均成為考驗各國能源發展最重要的課題,而在高油價及氣候暖化的雙重壓力下,已促使替代能源或新能源的開發蓬勃發展。藉由前述對於國際石油與替代能源發展情勢之分析,台灣在面臨國際石油問題之因應,本文提出可參採建議為,因應持續高油價可能引發的民生物價及經濟的衝擊,開放並鼓勵國內廠商赴海外合作共同探勘油田,重新檢討石油安全存量,積極開放油品市場,加速「再生能源發展條例」的立法。 / The greater part of the world’s remaining reserves of petroleum lie in the unstable Middle East region, while global petroleum needs are likely to continue to grow steadily in the future because the emerging giants of he world economy will require ever more energy for the unprecedented pace of economic development. In addition, environmental issues, a growing concern over last three decades, makes petroleum problem more complicated. With a view on economic analysis, the main findings of this research are the supply of global petroleum is unstable and finite, and the demand of global petroleum will continue to grow steadily. To solve this problem, all countries are searching for petroleum security and alternative energy. The prices of petroleum still matter to the health of the world economy, while the impact of high price of petroleum seems less injure than before. Compared to 1970s, the oil crisis, as a result of the oil supply disruptions, resulted in economic downturn, it now contains different issues both in demand and supply which present particular challenges that influence energy agendas. According to these findings, we suggest our government should adequately reflect the impact of high price of petroleum, encourage firms to cooperate internationally in explore petroleum abroad, review strategic petroleum reserve, and accelerate to legislate on regulations of development for renewable energy.
582

Utredningsarbete och upprättande av maritima kulturreservat : kultur, natur och reservat / The Investigatory work and establishing of maritime cultural reserves : culture, nature and reserves

Magnusson, Anders January 2017 (has links)
Since 1999 it has been possible for Swedish municipalities and the Swedish county administrative board to establish cultural reserves to protect particularly valuable cultural landscape. The protective character of the cultural reserve is supposed to be equivalent to the one found in nature reserves. The separation between the two protective forms have led to a marginalization of the protection of cultural landscape. This thesis has, using Posthumanist theory, studied the investigation process preceding the establishing of three maritime cultural reserves. The thesis also investigates if the general work with cultural landscape could benefit from a Posthumanist approach. To reach the purpose of this thesis, three research questions were formed: how does laws and conventions relate to Posthumanist theory, which values are highlighted in the process of investigating valuable landscapes and how does the practical work with investigating maritime cultural landscape manifest itself? The source material for the thesis consists of a study of documentation, laws and conventions. It also includes an interview study with informants at the Swedish heritage board, The Swedish National Maritime Museums and two persons responsible for the Cultural reserves at the municipality of Haninge and the Swedish county administrative board of Gävleborg. Research shows that the work with managing maritime cultural landscape and preservation would benefit from the use of a Posthumanist approach. The laws and guidelines that exists, based on euro-american definitions of what a valuable landscape is, limits the informants in their work to preserve all aspects of the landscape. Nature and culture are interlaced and cannot be separated. A landscape management system that acknowledge this and allows the public to be a part of the creation of cultural heritage, will lead to a more sustainable preservation. This document is a two years’ master´s thesis in Archive, Library and Museums studies.
583

SECURITY OF SUPPLY DURING THE ENERGY TRANSITION:THE ROLE OF CAPACITY MECHANISMS

Bhagwat, Pradyumna January 2016 (has links)
The push for clean energy has caused a rapid growth of renewables in the electricity supply mix of the EU. Although one would assume that the impact of these technologies is entirely positive, recent research and experience indicate that there is reason for concern namely regarding the security of supply. In this context, the concern is how renewable energy sources (RES) affect the business case of conventional power generation. In response to this concern, capacity mechanisms are being considered or have already been implemented by various member states of the EU. However, in a highly interconnected electricity system, such as the one in Europe, there appears to be a risk that the uncoordinated implementation of capacity mechanisms may cause unintended cross-border effects. This research explored the performance of various capacity mechanisms in an electricity system with a strong growth in the portfolio share of variable renewable energy sources (RES). The cross-border effects of implementing various capacity mechanisms in an interconnected power system were also analyzed. In this research, two capacity mechanisms, namely a strategic reserve and a capacity market, were modeled as extensions to the EMLab-Generation agent-based model. Furthermore, two variations of a capacity market were analyzed. The first was a yearly capacity market design and the second was a forward capacity market with long term contracts. A survey of experts on the US capacity markets supplemented the modeling work with practical insights. / <p>QC 20161006</p><p>The Doctoral Degrees issued upon completion of the programme are issued by Comillas Pontifical University, Delft University of Technology and KTH Royal Institute of Technology. The invested degrees are official in Spain, the Netherlands and Sweden, respectively.</p><p>copyright (c) 2016 P. C. Bhagwat</p>
584

CONSEQUENCES OF VINE INFESTATION: LINKING ABIOTIC INFLUENCES AND BIOTIC INTERACTIONS TO SUCCESSIONAL AND STRUCTURAL CHANGES IN COASTAL COMMUNITIES

Bissett, Spencer N 01 January 2015 (has links)
Located at the interfaces of terrestrial and marine environments, coastal habitats are inherently vulnerable to the effects of global change. Barrier island systems in particular serve not only as protective buffers against storm events, but also as sentinel ecosystems for observation of the impacts of sea level rise, and of increasing storm frequency and intensity. In the mid-Atlantic region, shrub thickets of Morella species compose the dominant forest community. The often monospecific nature of these plant community assemblages is advantageous to ecological studies and cross-scale applications; the relatively low diversity facilitates transitions between scales. My objective was to investigate the distribution and community roles of lianas in mid-Atlantic barrier island forest communities. I quantified environmental variables at two barrier habitats with differing site management histories and corresponding topography, and found that abiotic factors affected distributions of woody species, which subsequently affected vine species distributions. Some association of prevalent vine species with the common woody plants Prunus serotina and Morella cerifera was observed, though neither vines nor woody species demonstrated significant species-specific phytosociological associations. Vines demonstrated a long-lasting effect of arresting or delaying succession, and are potentially responsible for the lack of redevelopment of mature maritime forest at these sites. At Hog Island, Virginia, remotely-sensed data were utilized to determine the three-dimensional structural effects of vine infiltration in woody canopies. Vines were found to reduce canopy height and depth, and increase density, short-term diversity, and light-intercepting biomass. Significant vine infiltration can accelerate senescence of shrub thickets, but often results in persistent tangled masses of vegetation which reduce recruitment of later-successional species. These effects may represent long-term, lasting impacts of vine establishment and expansion in these habitats, affecting community succession towards diverse and stable maritime forest, and significantly altering resource dynamics in these sensitive ecosystems.
585

Differential Response of Barrier Island Dune Grasses to Species Interactions and Burial

Harris, April 01 January 2016 (has links)
Dune grasses are integral to biogeomorphic feedbacks that create and alter foredunes and barrier island stability. In a glasshouse study, Ammophila breviligulata Fern. and Uniola paniculata L. were planted together and subjected to sand burial to quantify morphological and physiological response. Ammophila breviligulata physiological and morphological performance declined when planted with U. paniculata but U. paniculata was not affected when planted with A. breviligulata. Burial had a positive effect on A. breviligulata and U. paniculata as indicated by electron transport rate and total biomass at the end of the experiment. Due to their different growth strategies, A. breviligulata and U. paniculata form continuous versus hummocky dunes, respectively. As global temperatures rise and U. paniculata migrates into A. breviligulata dominated habitat, A. breviligulata performance may diminish, and changes in dune form could result in altered island stability via increased overwash. Foredune community structure could also change due to the shift in dominant species which could alter dune succession.
586

Přírodovědný a historický pohled na oblast Dolního Poohří mezi Libochovicemi a Budyní nad Ohří / Natural and Historical View of the Area Dolní Poohří between Libochovice and Budyně nad Ohří

Burdová, Michaela January 2015 (has links)
Title: Natural and Historical view of the area Dolní Poohří between Libochovice and Budyně nad Ohří. Abstract: This presented thesis deals with detailed characteristics of Dolní Poohří in the area between Libochovice and Budyně nad Ohří. The theoretical part presents a general research of the area from the natural scientific and historical points of view. It outlines geological and pedological situation of the area which influences plant composition. Majority of the thesis is dedicated to the ecosystem of bottomland woods and to their historical evolution in the area of Dolní Poohří. It focuses on the flora and dendroflora of the observed locality and links them to mutual connection. It also summarizes individual local species of vegetation. This thesis also describes the history of the area and points out especially castle area Libochovice and Budyně nad Ohří from the historical point of view. It offers a brief historical overview of modifications of castle garden and park, as well as their current situation and plant composition. In the practical part, an educational tourist trail from Libochovice to Budyně nad Ohří has been designed. Route description, graphics and contents of the information panels, as well as work-lists for elementary and high school students are parts of the project design. An...
587

Critique de la raison neurologique / Critique of Neurological Reason

Zeghoudi, Anne-Céline 11 February 2013 (has links)
La discipline neurologique met en présence des soignants sains et des patients frappés de handicaps extrêmes auxquels le progrès médico-technique, fondé au XVIIe sur la mathématisation de la nature et le modèle du « corps-machine », n’a pas mis de terme. Comment se représenter l’aphasie, l’anosognosie, les altérations motrices et sensorielles chez autrui ? On se réfèrera aux travaux de Husserl et aux phénoménologues du corps pour approcher le mystère du vécu de la chair dans la maladie neurologique autrement que la sémiologie conventionnelle l’enseigne. Ce contact bouleversant avec les grands cérébrolésés n’est pas exempt d’intérêt, voire de jouissance : le spectacle du dépouillement humain par la perte du langage, du mouvement ou d’autres attributs, pourrait, dans un effet de miroir, et par une « association accouplante », permettre au témoin ici neurologue de se démonter lui-même et tendre vers l’élucidation de sa propre chair. Mais le système nerveux, par quoi la douleur ou le plaisir se manifestent à la conscience et au corps, qui afflige en même tant qu’il est affligé, est condamné à la forclusion du fait de son rôle nécessaire de médiateur physiologique. L’exclusivité d’une visée intentionnelle, dénoncée par Michel Henry, soutenue et entretenue par l’essor hégémonique de l’imagerie médicale, semble manquer ici la souffrance insoluble dans la donation extatique. Ce travail qui proposait, dans une démarche critique, de revisiter les soubassements du savoir neurologique, nous conduit vers une aporie : quelle est la phénoménologie du handicap neurologique s’il ne s’écrit ni ne se lit en termes positifs ? Devant l’insuffisance du logos à dire les altérations du monde et des vécus de la chair, s’invitent la réserve puis la métaphore artistique. C’est spécifiquement le travail du peintre Simon Hantaï qui ouvrira une voie entre phénomène mondain et incarnation. Il s’agira avec lui, dans un renoncement au savoir totalisant, d’apprendre à mettre en perspective les données des neurosciences et, ce que ni la science ni l’empathie pour autrui ne peuvent expliciter. Nous suggèrerons d’intégrer à la pratique médicale neurologique une démarche éthique autrement appelée « sagesse des limites » ; limites entre les savoirs, dont la figure toujours complexe, instable et miroitante, n’est pas sans évoquer une dimension baroque de la neurologie. / [Summary made by Reverso] The neurological discipline puts in the presence of nursing healthy and patients struck by extreme handicaps in which the medical technical progress, based(established) in the XVIIth on the mathématisation of the nature and the model of the "body-machine", did not put term. How to represent itself the aphasia, the anosognosie, the driving and sensory changes to others? We shall refer to the works of Husserl and to the phénoménologues of the body to approach the mystery of the real-life experience of the flesh in the neurological disease otherwise than the conventional semiology teaches him(it). This contact upsetting with the cérébrolésés big is not exempt from interest, even from enjoyment: the show(entertainment) of the human perusal by the loss of the language, the movement or the other attributes, could, in an effect of mirror, and by an accouplante " association ", allow the witness(baton) here neurologist to get confused itself and to aim towards the clarification of its own flesh. But the nervous system, by which the pain or the pleasure show themselves in the consciousness and in the body, which saddens even so much that it is saddened, is condemned to the debarment because of its necessary role of physiological mediator. The exclusivity of a deliberate aim, denounced(cancelled) by Michel Henry, supported and maintained by the hegemonic development of the medical imaging, seems to miss here the insoluble suffering in the ecstatic donation. This work which suggested, in a critical approach(initiative), revisiting the bases of the neurological knowledge, leads(drives) us towards an aporia: what is the phenomenology of the neurological handicap if he does not spell nor is read in positive terms? In front of the insufficiency of logos to say the changes of the world and the real-life experiences of the flesh, invite each other the reserve then the artistic metaphor. It is specifically the work of the painter Simon Hantaï that will open a way between worldly phenomenon and embodiment. It will be a question with him, in a renunciation of the adding up knowledge, of learning to put in perspective the data of the neurosciences and, what neither the science nor the empathy for others can clarify. We shall suggest to integrate(join) into the neurological medical practice an ethical otherwise called approach(initiative) " wisdom of the limits "; limits between the knowledges, the face(figure) of which always complex, unstable and gleaming, is not without evoking a baroque dimension(size) of the neurology.
588

Des clichés protectionnistes aux approches intégratives : l'exemple des réserves naturelles de France / From rigid protection towards integrative conservation management in social-ecological systems : a study of French Nature Reserves

Therville, Clara 21 March 2013 (has links)
Les politiques de conservation de la nature ont largement évolué ces quarante dernières années. Si les premières aires protégées ont été créées selon un modèle ségrégatif, elles s’inscrivent aujourd’hui dans des modèles intégratifs. De fait, les aires protégées et leurs gestionnaires ne jouent plus les mêmes rôles au sein des socioécosystèmes. Leurs objectifs, leurs pratiques de conservation, les modes de régulation et de prise de décision, l’articulation avec les territoires environnants ont évolué. Nous nous concentrons ici sur les réserves naturelles françaises (RN), l’un des principaux outils réglementaires de protection de la nature en France. Nous caractérisons les interactions entre RN et territoires et les enjeux qui y sont liés, dans la perspective de cette transition ségrégatif – intégratif. Cette étude porte sur deux échelles distinctes : l’échelle nationale et l’ensemble des 277 RN, et l’échelle locale avec 10 études de cas. À l’échelle nationale, l’analyse de l’émergence des thématiques liées au développement durable des territoires dans le réseau des RN met en évidence les enjeux institutionnels, organisationnels, culturels et stratégiques de ce réseau, et permet de discuter la thèse d’une institutionnalisation inachevée. Nous montrons ensuite qu’il existe différents types de RN selon les pratiques mises en œuvre par les gestionnaires. Nous analysons ces investissements variés sur la base de trois types de facteurs : (i) les caractéristiques géographiques des RN ; (ii) le gestionnaire : son système de valeur et son profil socioculturel et (iii) les caractéristiques du territoire environnant. Avec nos 10 cas d’étude, nous caractérisons les socioécosystèmes constitués par les RN et les territoires environnants. Nous analysons dans le détail l’articulation identifiée à l’échelle nationale entre perceptions des acteurs, pratiques, caractéristiques des sites, des territoires et des gestionnaires, à l’intérieur des RN, mais également au-delà de leurs limites spatiales et fonctionnelles. À l’aide des cadres d’analyse des socioécosystèmes complexes, de la solidarité écologique, de la political ecology et de l’analyse institutionnelle, nous identifions les interactions entre RN et territoire, et mettons en lumière les limites des arrangements institutionnels mis en œuvre. Nous concluons sur la notion de trajectoire des sites, et dans une perspective de recherche appliquée, sur les implications de nos résultats pour le réseau des RN. / During the last four decades, nature conservation in protected areas (PAs) has been characterized by major changes. Early PAs have often been perceived as human-exclusion areas, whereas modern PAs have been designated more as integrated conservation and development projects. This evolution has involved major changes in objectives, management practices, governance systems, and relationship of PA’s to their surrounding environments. Nowadays, PA managers take into account processes that go beyond PA boundaries, investigate economic and social issues of development, and pay a special attention to local involvement. Here, we focus on French Nature Reserves (NRs), one of the main regulatory tools of the French nature protection policy. We characterize the interactions between NRs and the socioecosystems in which they interact. This study focus on two scales: the national scale and all of the 277 nature reserves, and the local scale with 10 case studies. At the national scale, we show how the emergence of sustainable development discourses in the nature reserve network have led us to analyze institutional, organizational, cultural and political issues. We describe the distribution of NR practices along a gradient going from a traditional model to an integrative model. We explain the observed practices as a combination of three types of variables : (i) general geographical characteristics of the NRs; (ii) value systems and perceptions of managers and (iii) characteristics of surrounding environments. On the basis of 10 case studies, we characterize the socioecosystems constituted by NRs and their surroundings territories. We analyze the articulation identified at the national scale between conservation practices, characteristics of NRs, territories and managers, both inside the reserves and beyond their spatial and functional boundaries. On the basis of frameworks for analyzing sustainability of complex socioecosystems, ecological solidarity, political ecology and institutional approaches, we identify the key variables in the implementation of collective action and adaptive management of both NRs and socioecosystems. Our analysis illustrates the limits of the implemented institutional arrangements. We conclude on the idea of NR trajectories, and on the practical implications of this work for the French NR system.
589

Stochastické modely tvorby škodních rezerv / Stochastic Loss Reserving Models

Košová, Nataša January 2012 (has links)
In present thesis we study and describe a stochastic loss reserve model for individual insurers. Specifically, it is the model based on the three following features. Modelling of expected claims depends on unknown parameters which estimates need to be the most accurate. Aggregated occurred and paid losses for particular years are modelled by a collective risk model. The final reserve is estimated by Bayesian methodology that uses a prior information from a significant number of insurers. Part of the thesis is also an implementation of the program that calculates reserves by using our model and its testing on simulated data.
590

Výzkum ekologické validity kognitivního trénování / Ecological validity of cognitive training research

Bláhová, Lucie January 2013 (has links)
This Master thesis is focused on ecological validity of a cognitive training in university students. Forty-five students participated in three months research during which 30 of them took regular personalized cognitive training using CogniFit programme on their computers. The study examines the impact of the cogntitive training on everyday cognitive functioning of students. The scientific methods used for the ecological validity research were the following self-reporting questionnaires: Cognititive Failure Questionnaire, Everyday Memory Questionnaire and Dysexecutive Questinnaire. Students also filled in Schwartz Outcome Scale - 10 and Self-image questionnaire for detailed exploration of more variables. For the research, we applied test-retest design and used control group of fifteen students for results comparison. Analysis of the gathered data proved little evidence of ecological validity of cognitive training, which can be attributed to considerable cognitive stress at students. An unexpected outcome of the study which proved to be very significant is relation between executive functions and well-being of a student. This relation was confirmed repeatedly. Possible improvements of methodology and also problem with randomization of students is discussed. Proposal for the further development of...

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