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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.
121

Coyote Foraging Ecology, Vigilance, and Behavioral Cascades in Response to Gray Wolf Reintroduction in Yellowstone National Park

Switalski, T. Adam 01 May 2002 (has links)
Vigilance behavior can aid in the detection of predators and may also play a role in observation of conspecifics, in food acquisition, and in the prevention of kleptoparasitism. However, in most occasions, vigilance is most important as an antipredator function. Generally, factors that increase the risk of predation also increase the amount of vigilance. We examined whether the reintroduction of the large predator, the wolf, in Yellowstone National Park (YNP) would influence coyote vigilance and foraging ecology. From December 1997 to July 2000, we collected 1743 h of coyote activity budgets. Coyote home ranges occurred within wolf territories (termed high-use or nonbuffer zone areas) and also between them in buffer zones. In high wolf use areas as well as when wolves were present, coyotes fed on carcasses much more; however, they increased the amount of vigilance and decreased rest to prevent predation. Wolf kills may provide a quick source of food and be energetically advantageous to coyotes; however, costs include increased vigilance, decreased rest, and a higher predation risk. Vigilance and avoidance behavioral responses to the reintroduction of large predators may ultimately be more common outcomes than actual killing by competing carnivores of prey. Keystone carnivore reintroductions have a variety of cascading effects throughout the ecosystem and can be driven by both numeric responses (trophic cascades) and behavioral responses ("behavioral cascades"). Behavioral cascades resulting from increased vigilance or spatial changes may lead ultimately to numeric changes and trophic cascades.
122

Hydrogeology of the McKinney Butte Area: Sisters, Oregon

Hackett, Joshua Andrew 01 January 2011 (has links)
McKinney Butte, a late Tertiary andesite vent and flow complex, is located near the town of Sisters, Oregon, in the upper Deschutes Basin, and is situated along the structural trend that forms the eastern margin of the High Cascades graben (Sisters fault zone and Green Ridge). Rapid development and over appropriated surface water resources in this area have led to an increased dependence upon groundwater resources. A primary concern of resource managers is the potential impact of expanding groundwater use on stream flows and spring discharge. Two sets of springs (McKinney Butte Springs and Camp Polk Springs) discharge to Whychus Creek along the east flank of McKinney Butte, and during low-flow conditions supply a substantial component of the total flow in the creek. Despite their contribution to Whychus Creek, the springs along McKinney Butte are small-scale features and have received less attention than larger volume (> 2 m³/s) springs that occur in the basin (i.e., Metolius Spring and Lower Opal Springs). This study used discharge measurements in Whychus Creek upstream and downstream of the springs, and mixing models using measurements of electrical conductivity and temperature in the springs and Whychus Creek to determine the contribution of the springs to the creek. Isotopic, thermal, and geochemical signatures for the McKinney Butte and Camp Polk Springs, and local streams (Whychus Creek and Indian Ford Creek) and springs (Metolius Spring, Paulina Spring, Alder Springs, and Lower Opal Spring) were assessed to determine the source(s) of the McKinney Butte and Camp Polk Springs. The discharge and hydrochemical data along with hydraulic head data from local wells were used in the development of a conceptual model of groundwater flow for the McKinney Butte area. Discharge from the McKinney Butte Springs supplies the majority of water to Whychus Creek on the east flank of McKinney Butte (~0.20 m³/s), provides up to 46% of the flow in the creek, and is relatively stable throughout the year. Discharge from the Camp Polk Springs is less than 0.05 m³/s. Isotopic, thermal, and geochemical signatures indicate distinct sources for the McKinney Butte and Camp Polk Springs. Groundwater discharged at the McKinney Butte Springs is depleted in heavy stable isotopes (δD and δ¹⁸O) relative to the Camp Polk Springs. Recharge elevations inferred from stable isotope concentrations are 1800-1900 m for the McKinney Butte Springs and 950-1300 m for the Camp Polk Springs. Elevated water temperature in the McKinney Butte Springs relative to the average air temperature at the inferred recharge elevation indicates the presence of geothermal heat and implies deep circulation in the flow system. The temperature in the Camp Polk Springs is not elevated. The Camp Polk Springs, though not the McKinney Butte Springs, contain elevated concentrations of ions Cl, SO₄, and NO₃ that are indicative of contamination. The study results indicate the source of the Camp Polk Springs is shallow groundwater whereas the McKinney Butte Springs discharge water that has circulated deep in the groundwater flow system. Additionally, the hydrochemical traits of the McKinney Butte Springs are similar to Metolius Spring, suggesting discharge from the McKinney Butte Springs is controlled by the structural trend that forms the eastern margin of the High Cascades graben. The significant difference in discharge between the McKinney Butte Springs and Metolius spring may be related to the size of faults that occur locally.
123

A STUDY OF THE EFFECTS OF REVIEW, SOCIAL, AND ADOPTER CHARACTERISTICS IN MOBILE APP ADOPTION

Liu, Fengkun 20 October 2014 (has links)
No description available.
124

A search for particle showers at the edge of IceCube’s instrumented volume

Stößl, Johannes Achim 02 August 2017 (has links)
Unter den Methoden zur Suche nach Neutrino Ereignissen in IceCube versprechen Suchen nach Teilchenschauern, sogenannten Kaskaden eine gute Energieauflösung und einen verhätlnismässig geringen atmosphärischen Untergrund. Dadurch erreichen solche Suchen eine hohe Sensitivität für einen extraterrestrischen Neutrino Fluss. Bisher beschränkte sich die Suche nach solchen Ereignissen auf solche in einer inneren Region des IceCube Detektors. Das Detektorvolumen am Rand wurde bisher benutzt um den Untergrund von einfallenden atmosphärischen Muonen zu Unterdrücken. Diese Dissertation präsentiert eine Analyse von 2 Jahren IceCube Daten und demonstriert die Möglichkeit, diese Veto Region für die Suche nach kaskadenartigen Ereignissen zu nutzen. Dadurch wird das nutzbare Detektorvolumen um « 80% vergrößert und die Statistik im hochenergetischen Bereich des Neutrino Spektrums durch das Hinzufügen von 18 Neutrino Kandidaten im Energiebereich von 34 - 578 TeV erhöht. Das Ergebnis ist in Übereinstimmung mit dem etablierten Nachweis eines extraterrestrischen Neutrino Flusses, eine reine Untergrund Hypothese kan mit 2.7 sigma verworfen werden und die Daten favorisieren einen extraterrestrischen Neutrino Fluss mit einem ungebrochen Potenzgesetz mit einem Index von γ ^ 2.50+-0.28 in guter Übereinstimmung mit bisherigen Ergebnissen von IceCube. / Among the analysis strategies used in IceCube, searches for neutrinoinduced particle showers, so called cascades, provide good energy resolution and a relative low atmospheric background. Therefore, they provide large sensitivity to the extraterrestrial neutrino flux. Previously, these searches have been constrained to neutrino interactions in a center region of the instrumented volume. The volume at the border and surrounding the detector was needed to veto the incident atmospheric muon background. This dissertation presents an analysis of two years of IceCube data and demonstrates the feasibility of using the veto region for cascade searches. This increases the usable detector volume by « 80% and improves the statistic in the high-energy tail of the neutrino spectrum by adding 18 neutrino candidates in the energy range from 34 to 576 TeV. The result is supports the established evidence for the extraterrestrial neutrino flux by rejecting the pure atmospheric background hypothesis at the 2.7 sigma level, the data prefers an extraterrestrial neutrino flux with a featureless power law with an index of γ^2.50+-0.28 well in agreement with previous IceCube results.
125

Land-use impacts on biodiversity and ecosystem functioning of complex multitrophic communities

Barnes, Andrew D. 19 November 2015 (has links)
No description available.
126

Strong interaction between two co-rotating vortices in rotating and stratified flows

Bambrey, Ross R. January 2007 (has links)
In this study we investigate the interactions between two co-rotating vortices. These vortices are subject to rapid rotation and stable stratification such as are found in planetary atmospheres and oceans. By conducting a large number of simulations of vortex interactions, we intend to provide an overview of the interactions that could occur in geophysical turbulence. We consider a wide parameter space covering the vortices height-to-width aspect-ratios, their volume ratios and the vertical offset between them. The vortices are initially separated in the horizontal so that they reside at an estimated margin of stability. The vortices are then allowed to evolve for a period of approximately 20 vortex revolutions. We find that the most commonly observed interaction under the quasi-geostrophic (QG) regime is partial-merger, where only part of the smaller vortex is incorporated into the larger, stronger vortex. On the other hand, a large number of filamentary and small scale structures are generated during the interaction. We find that, despite the proliferation of small-scale structures, the self-induced vortex energy exhibits a mean `inverse-cascade' to larger scale structures. Interestingly we observe a range of intermediate-scale structures that are preferentially sheared out during the interactions, leaving two vortex populations, one of large-scale vortices and one of small-scale vortices. We take a subset of the parameter space used for the QG study and perform simulations using a non-hydrostatic model. This system, free of the layer-wise two-dimensional constraints and geostrophic balance of the QG model, allows for the generation of inertia-gravity waves and ageostrophic advection. The study of the interactions between two co-rotating, non-hydrostatic vortices is performed over four different Rossby numbers, two positive and two negative, allowing for the comparison of cyclonic and anti-cyclonic interactions. It is found that a greater amount of wave-like activity is generated during the interactions in anticyclonic situations. We also see distinct qualitative differences between the interactions for cyclonic and anti-cyclonic regimes.
127

Service quality and profit control in utility computing service life cycles

Heckmann, Benjamin January 2013 (has links)
Utility Computing is one of the most discussed business models in the context of Cloud Computing. Service providers are more and more pushed into the role of utilities by their customer's expectations. Subsequently, the demand for predictable service availability and pay-per-use pricing models increases. Furthermore, for providers, a new opportunity to optimise resource usage offers arises, resulting from new virtualisation techniques. In this context, the control of service quality and profit depends on a deep understanding of the representation of the relationship between business and technique. This research analyses the relationship between the business model of Utility Computing and Service-oriented Computing architectures hosted in Cloud environments. The relations are clarified in detail for the entire service life cycle and throughout all architectural layers. Based on the elaborated relations, an approach to a delivery framework is evolved, in order to enable the optimisation of the relation attributes, while the service implementation passes through business planning, development, and operations. Related work from academic literature does not cover the collected requirements on service offers in this context. This finding is revealed by a critical review of approaches in the fields of Cloud Computing, Grid Computing, and Application Clusters. The related work is analysed regarding appropriate provision architectures and quality assurance approaches. The main concepts of the delivery framework are evaluated based on a simulation model. To demonstrate the ability of the framework to model complex pay-per-use service cascades in Cloud environments, several experiments have been conducted. First outcomes proof that the contributions of this research undoubtedly enable the optimisation of service quality and profit in Cloud-based Service-oriented Computing architectures.
128

Topics in gauge/gravity dualities / Estudos na dualidade calibre/gravidade

Romero, Jose Renato Sanchez 11 November 2014 (has links)
This thesis consists in a self-contained study of gauge/gravity dualities in the line of the Klebanov-Witten model. Here we explore first the known Maldacena duality that relates N=4 SYM theory in four dimensions to type IIB supergravity on AdS_5×S^5 in reasonable detail, after some necessary preliminaries on supersymmetric gauge theories, where we display in detail the supersymmetry algebra and representations for N 1 supersymmetry. There we also construct the so-called superfields that will be helpful to write invariant lagrangians for gauge theoriesmreadily, and then useful to construct the gauge theory side of the Klebanov-Witten model. In the original AdS/CFT correspondence and its phenomenologically interesting extensions, Dp-branes as solutions of supergravity and nonperturbative objects in string theory where gauge theory lives are crucial. So, to preserve the self-contained nature of this work, we include a brief review of superstring theory addressed to understand the need to include this higher-dimensional objects by T-duality and, at low-energy limit of the string theory, as solutions of the Einstein equations. The first climax of this work occurs when we use all we learned to establish the Maldacena conjecture, N=4 SU(Nc) SYM theory we study in the supersymmetry chapter, living on the four-dimensional worldvolume of a stack of Nc D3-branes in a flat-space, corresponds exactly to type IIB supergravity on AdS_5×S^5 .In order to prove it, we match symmetries and operators with states in both sides. But actually this corresponds to the weak form of the correspondence, because it is not possible to handle neither string theory or gauge theory at strong coupling. The focus and main motive to have to learn the first hundred of pages here will be to extend the dual gauge theory we studied in AdS/CFT towards more realistic gauge theories as duals of some supergravity theory. The Klebanov-Witten model, consists in replacing the five-sphere in the gravity background of type IIB for a more interesting Einstein manifold X5 , a coset space called T^1,1 .The resulting dual gauge theory is expected to be less supersymmetric, and it is indeed N = 1 superconformal field theory with matter content in the bifundamental representation of the gauge group SU(N)×SU(N), and a quartic superpotential that exhibits SU(2)×SU(2)×U(1) global symmetry, which is precisely the symmetry of the coset space in the gravity side. This is not the end of the story, the Klebanov-Witten model extended the Maldacena correspondence and found as a dual gauge theory a less supersymmetric but still conformal theory. Breaking of the conformal theory, proposed by Klebanov, Nekrasov and Tseytlin, is achieved by introducing fractional M D3-branes in addition to the N regular D3-branes. The resulting theory is an SU(N+M)×SU(N) gauge theory with N = 1 supersymmetry, no longer conformal and then a little more interesting as a part of the crusade to find a QCD-like theory. This is still not the end, the last model suffers from a singularity in the deep IR, rendering the gravitational description invalid in that regime. It was conjectured that the strong dynamics of the gauge theory should somehow resolve this problem. Klebanov, again, and Strassler showed that this conjecture was correct, and argue that the RG flow is in fact an infinite series of Seiberg duality transformations- a cascade - in which the number of colors repeatedly drops from N NM , so the gaugegroup changes from SU(N+M)×SU(N) to SU(NM) ×SU(N). This process can be repeated until the IR limit where the gauge group simply becomes SU(M). So, at the end we get a N=1 SU(M) gauge theory, a QCD-like theory. We say that the standard model itself may lie at the base of a duality cascade. / Essa tese consiste num estudo autocontido das dualidades calibre/gravidade na linha do modelo do Klebanov-Witten. Aqui nos exploramos primeiro de um jeito razoavelmente detalhado,a conhecida dualidade do Maldacena que relaciona a teoria N=4 SYM em quatro dimensões com as supercordas tipo IIB no espaço AdS_5×S^5, depois de alguns preliminares necessários sobre teorias supersimétricas de calibre, onde nós mostramos em detalhe à algebra supersimétrica e as representações para N 1 supersimetria. Nós também construímos os conhecidos supercampos que são úteis para escrever lagrangianas invariantes para teorias de calibre facilmente, e então serão úteis para construir a teoría de calibre do modelo de Klebanov-Witten. Na correspondência AdS/CFT original e as suas extensões fenomenologicamente interessantes, as Dp-branas, como soluções de supergravidade e objetos não perturbativos na teoria de cordas onde as teorias de calibre moram, são essenciais. Assim ,a fim de preservar a natureza autocontida desse trabalho, nós incluímos uma breve revisão sobre teoria de supercordas dirigida a entender a necessidade de incluir esses objetos extra-dimensionais usando dualidade-T e, no limite de baixa-energia da teoria de cordas, como soluções das equações de Einstein. O primeiro clímax desse trabalho ocorre quando nós usamos tudo o que aprendemos para estabelecer a conjectura do Maldacena, a teoria de calibre N=4 SYM que nós estudamos no capítulo de supersimetria, morando no volume de mundo quadridimensional de uma pilha de Nc D3-branas (sim, o subscrito c significa cor!) em espaço plano, corresponde exatamente à teoria de supergravidade tipo IIB no espaço AdS_5×S^5 . A fim de testar ela, nós identificamos simetrias e operadores com estados em ambos lados da dualidade. Mas na verdade isto corresponde à forma fraca da correspondência, porque não é possível lidar nem com a teoria de cordas nem com a teoria de calibre no limite de acoplamento forte. O foco e motivo principal de porque nós temos que aprender as primeiras cem páginas aqui, será estender a teoria de calibre dual que estudamos em AdS/CFT, para teorias de calibre mais realisticas como duais de alguma teoria de supergravidade. O modelo do Klebanov-Witten, consiste em substituir a esfera de cinco dimensões no fundo de supergravidade da teoria de supercordas tipo IIB por um espaço que é mais interessante X5, um espaço coset chamado T^1,1. Nós esperamos que a teoria de calibre dual que resulta é menos supersimetrica, e na verdade é N =1 superconforme com um conteúdo de matéria na representação bifundamental do grupo de calibre SU(N)×SU(N), e um superpotencial quártico que tem simetria global SU(2)×SU(2)×U(1), que é precisamente a simetria do espaço coset no lado da gravidade. Mas isso não é tudo, o modelo do Klebanov-Witten estendeu a correspondência do Maldacena e encontrou como teoria dual uma teoria menos supersimetrica mas ainda conforme. A quebra da simetria conforme, proposta pelo Klebanov, Nekrasov e Tseytlin, é obtida introduzindo M D3-branas fracionais além das N D3-branas regulares. A teoria resultante é uma teoria de calibre SU(N+M)×SU(N) com N = 1 supersimetria, não mais conforme e então um pouco mais interessante como parte da nossa cruzada para encontrar uma teoria tipo-QCD. Isso ainda não é o final, o modelo anterior sofre de uma singularidade no IR profundo, tornando inválido a descrição gravitacional. Foi conjeturado então que a dinâmica do acoplamento forte na teoria de gauge deveria de algum jeito resolver esse problema. Klebanov, de novo, e Strassler mostraram que essa conjetura foi correta, e argumentaram que o fluxo do GR é de fato uma serie infinita de transformações de dualidade de Seiberg - uma cascata - onde o numero de cores cai repetidamente de NNM, e o grupo de calibre muda de SU(N+M)×SU(N) a SU(NM)×SU(N). O processo pode ser repetido até o limite IV onde o grupo de calibre simplesmente torna-se SU(M). Então, no final nós obtemos uma N = 1 teoria de calibre SU (M ), ou seja uma teoria tipo-QCD. Então, nós dissemos que o modelo padrão mesmo pode se situar na base da cascata de dualidade.
129

Cascatas de incertezas, impactos climáticos perigosos e negociações internacionais sobre mudança de clima global - um modelo exploratório / Cascatas de Incertezas, Impactos Climáticos Perigosos e Negociações Internacionais sobre Mudança de Clima Global : Um Modelo Exploratório

Aimola, Luís Antônio Lacerda 19 June 2006 (has links)
O problema das mudanças climáticas globais somente pode ser resolvido através de um longo processo de coordenação política internacional no qual os principais atores são os governos dos Estados Nacionais. O Protocolo de Quioto é o primeiro acordo internacional para controlar as emissões de gases de efeito estufa, e muitas outras rodadas de negociações ocorrerão ao longo deste século gerando novos acordos com o mesmo objetivo. Inúmeros fatores, relacionados de forma complexa, têm influenciado e influenciarão os resultados desses futuros acordos. Dentre os principais estão as incertezas sobre os vários aspectos, físicos, biológicos, econômicos e políticos, do problema das mudanças climáticas. O objetivo deste trabalho foi construir um modelo de análise integrada, que tornasse transparente os principais elementos e elos da cascata de incertezas existente no problema das mudanças climáticas e a sua influência nos resultados daquelas negociações e nos permitisse fazer simulações exploratórias sobre os efeitos da evolução dessas incertezas sobre os resultados da seqüência de negociações após o Protocolo de Quioto. O modelo representa de forma estilizada importantes elementos que participam da estrutura de decisão coletiva sobre abatimento de reduções de emissões e em alguns aspectos é mais realista que vários modelos existentes sobre tomada de decisões sobre mudança de clima. Ele é composto de um módulo que representa o sistema do clima, um módulo que representa as economias nacionais, um módulo que representa os tomadores de decisões governamentais e um módulo que representa as negociações sobre reduções de emissões. Os tomadores de decisões são representados como agentes que têm planos de desenvolvimento econômico para seus países e modelos sobre como o clima global e regional e as suas economias funcionam, o que lhes permite fazerem projeções futuras do aquecimento global, das suas economias e emissões, e do impacto que a mudança de clima produzirá em seu território. Dessa forma podem estimar o impacto que o aquecimento global poderá ter sobre seus planos de desenvolvimento. Essas análises são feitas dentro de um horizonte de antecipação que depende do grau de incertezas na época em que as projeções são realizadas. Representamos algumas das principais incertezas na ciência do clima e análise econômica do problema através de distribuições de probabilidades de certos parâmetros chave, tais como a sensibilidade climática e a difusividade térmica do Oceano, que podem variar ao longo do tempo. Existe uma infinidade de cenários possíveis de evolução dessas incertezas, mas somente alguns com significados intuitivos importantes. Uma negociação sobre cotas de reduções de emissões é representada como um jogo não-cooperativo, e o acordo entre os países é um equilíbrio de Nash desse jogo. Cada governo, antes de ir à mesa de negociações, baseado nestas projeções e nas possíveis ações dos outros governos, elabora suas estratégias sobre o quanto abater de suas emissões. O resultado final de um jogo é influenciado pelas distribuições de probabilidades que representam as incertezas da época em que cada agente faz suas projeções. Algumas distribuições em algumas épocas podem revelar aos agentes a probabilidade de impactos climáticos perigosos em suas economias, influenciando fortemente as suas escolhas de abatimento e o resultados das negociações. Esse ciclo de projeções-análise-negociação se repete várias vezes ao longo do tempo definindo uma seqüência de acordos de reduções de emissões, um conseqüente aquecimento global e uma distribuição de impactos regionais ao longo do mesmo período. A comparação das trajetórias finais de aquecimento e impactos gerados para cada cenário escolhido de evolução das incertezas ajuda-nos a compreender as possíveis evoluções das futuras negociações sobre abatimento de emissões. Implementamos uma versão simplificada do modelo em um programa de computador através da plataforma Microsoft Excel, considerando somente dois blocos de países. Com esse protótipo, é possível simular cenários de evolução das incertezas, representando evoluções possíveis da ciência do clima e a análise econômica do problema, e com isso estudar a influência dessas evoluções nos resultados de uma seqüência de negociações sobre cotas de reduções de emissões entre dois blocos de países, que uma vez definidos os valores de certos parâmetros, podem representar os países do Anexo I e Não-Anexo I da Convenção Quadro de Mudança de Clima das Nações Unidas. Nesse caso o Protocolo de Quioto é o primeiro acordo de uma série de acordos ao longo do Século XXI. O modelo foi construído apoiando-se na literatura tradicional de modelagem integrada em mudanças climáticas, mas inova a pesquisa nesta área em vários pontos importantes. Dentre eles está a variação gradual de várias incertezas e a incorporação de uma interpretação do conceito de impactos climáticos perigosos conforme o Artigo 2 da Convenção Quadro e seu papel nos resultados das negociações. A linguagem e a plataforma utilizada nos permite comunicar de forma clara os elos da cascata de incertezas e sua influência sobre as negociações, tanto a cientistas, quanto a analistas econômicos e políticos envolvidos com o tema. A plataforma utilizada torna também o programa aberto para análises críticas e modificações a uma larga classe de analistas do tema, além de poder ser utilizado no ensino, que ainda carece de ferramentas pedagógicas que permitam uma ampla divulgação desse tema a não especialistas. Apesar de ser um modelo sobre mudanças climáticas, os vários módulos têm uma estrutura conceitual que lhes permite serem adaptados para tratar outras questões ambientais globais e regionais onde as soluções baseiam-se em tomada de decisão coletiva negociada e sob incertezas. / The problem of the global climate change only can to be solved through a long term process of international political coordination which the principal actors are the governments of the National States. The Kyoto Protocol is the first international agreement to control the greenhouse gas (GHG) emissions, and the others rounds of negotiations will happen through this century producing new deals with the same goal. A number of factors related of a complex way, have influenced and will influence the results of these future agreements. Among the principal factors, are the uncertainties about the physical, biological, ecological, economical and poltical aspects of the global climate change problem. The goal of this work was to contruct a integrated assessment model, that show in a transparent way some the majors elements and links of the uncertainties cascade that exist in the problem of the climate change, and their influence on the results on that negotiations. The model permit us to make exploratory simulations about the effects of the evolution that uncertainties in the results of the sequence of negotiations after the Kyoto Protocol. The model represent in a stylized way important elements that participate in the structure of collective decision making about abatement of GHG emissions and in some aspects is more realistic that several existent models on decision making about climate change. It is composed of one module that represent the climate system, one module that represent the national economies, one module that represent the governmental decision makers and one module that represent the negotiations about reductions of GHG emissions. The climate model include a carbon cycle and an energetic balance simple models with white noise in the radiative forcing to repesent the natural climate variability. The economic models include abrupt changes in the damages functions. The The decision makers are represented as agents that have economical development plans for their countries and have models of the climate change and their national economies. These models permit to each one make projections on future global warming, economical growth, emissions and the climate impacts on each territory. Thus each agent can estimate the impact of the global warming on his development plan under a action of abatement of emissions. These analysis are made with the aid of a antecipation horizon that depends of the uncertainty levels in the epoch which the projections are made. We represented some of majors uncertainties in the climate science and economic analysis on the problem through probabilities distributions of certain key parameters, such that the climate sensibility and the ocean thermal diffusivity, which can to vary in time. There is a number of possible evolution scenarios for these uncertainties, but only a few with important intuitive means. We take only these more important scenarios to simulation. A negotiation on reduction quotas of emissions is represented as a non-cooperative game and the agreement between countries is a Nash equilibrium of the game. Each government before to negotiate choose his strategies on how much abate emissions based on his projections. The game final result is influenced by the probabilities distributions that represent the uncertainties in the epoch of the negotiations. Some distributions can reveal high probabilities for dangerous climate impacts in their economies, influencing strongly the choices of emission abatements and the results of negotiations. The cycle of projection-analysisnegotiation can to repeat many times defining a sequence of agreements and then a emission trajectory, and as consequence a global warming and distributions of regional impacts. The comparison of final trajectories of warming and impacts for each negotiations sequence help us to understand the possible evolutions of future negotiations and his role in the climate change problem.
130

Preserving Nature through Film: Wilderness Alps of Stehekin and the North Cascades, 1956-1968

Bergmann, Nicolas Timothy 20 June 2013 (has links)
On March 22, 1958 David Brower's film Wilderness Alps of Stehekin premiered to an audience of conservationists in Seattle, Washington. Almost two years in the making, the thirty-one minute film advocated the preservation of nature in Washington's North Cascades through the creation of a national park. Over the next decade, Wilderness Alps of Stehekin became the most influential publicity tool in the struggle to preserve the North Cascades. Because of the region's geographic isolation, the film was the first time many people throughout the nation were exposed to the scenic grandeur of the area. Images of craggy peaks and colorful alpine meadows resonated deeply with many Americans and persuaded them to join in the campaign. It was the voice of these citizens that led Congress to pass the North Cascades Act of 1968, which placed 674,000 acres of the North Cascades under the jurisdiction of the National Park Service. In this thesis I tell the creation story of North Cascades National Park from a conservationist perspective and trace the influence of Wilderness Alps of Stehekin within this context. Although the film was never shown in movie theaters and never aired on national television, many thousands viewed it from its premiere to the signing of the North Cascades Act. The film first introduced the idea of a North Cascades National Park, and it was important in convincing conservationists to unite around a national park solution. Ultimately, Wilderness Alps of Stehekin changed the approach activists took in the North Cascades and helped to preserve a wild and scenic nature experience for future generations through the protection of old-growth forests and alpine meadows.

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