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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.
71

The Rapsodie for Orchestra and Saxophone by Claude Debussy: a Comparison of Two Performance Editions

Seligson, Robert Jan 12 1900 (has links)
This paper discusses the historical background of the Rapsodie for Orchestra and Saxophone by Claude Debussy and includes a comparison of two piano performance editions. Chapter I includes information on Elise Hall, her work with the Boston Orchestra Club and the circumstances of her commission of Claude Debussy which yielded the Rapsodie. Chapter II discusses the Editions Durand piano reduction and the reasons for its neglect by saxophone performers. This chapter includes a study of the techniques used by Eugene Rousseau to create his arrangement of the Rapsodie for saxophone and piano. The study concludes that the arrangement by Rousseau is more attractive to saxophonists and will be performed more frequently than the Durand reduction.
72

Opportunities and barriers for an increased flexibility in residential consumers’ electricity consumption / Möjligheter och hinder för en ökad flexibilitet i elkonsumenters elanvändning

Sten, Amanda, Åström, Katja January 2016 (has links)
I Sverige står hushållen för en stor del av den slutliga elanvändningen och deras konsumtionsmönster bidrar till att skapa höga förbrukningstoppar, särskilt under vintermånaderna när elbehovet är som störst. Om hushållen kunde tänka sig att vara mer flexibla i när de använder el skulle förbrukningstoppar kunna dämpas avsevärt och balansen mellan elproduktion och elanvändning bli lättare att upprätthålla. Idag utnyttjas inte efterfrågeflexibilitet i någon större utsträckning, förutom den från vissa elintensiva industrier. Den flexibla kapacitet enskilda hushåll skulle kunna bidra med är naturligtvis lägre än hos industrier, men sammanslaget skulle hushållskunders flexibilitet kunna ge en substantiell inverkan på elsystemet. Vid låga utetemperaturer finns det en uppskattad potential att genomföra effektjusteringar om cirka 1 400 – 3 100 MW om värmelasten hos drygt hälften av samtliga eluppvärmda hus i Sverige omdisponeras till andra tidpunkter, och ytterligare några hundra MW om drygt hälften av samtliga hushåll i Sverige vore flexibla i när de använder hushållsel. Enligt en studie av Broberg m.fl. (2016) skulle drygt hälften av hushållen i Sverige kunna tänka sig att vara flexibla, beroende på vad flexibel innebär. Hushåll som använder el för uppvärmning kan vara flexibla genom att tillfälligt öka eller minska inomhustemperaturen, eller om de använder el i kombination med något annat uppvärmningssätt – genom att byta energikälla. Justeringen kan även ske automatiskt om uppvärmningssystemet är utrustat med central styrutrustning. Om ett stort antal kunders flexibla laster samlas ihop av en marknadsaktör skulle den totala flexibla lasten kunna säljas som kapacitet på grossistmarknaden för el eller erbjudas som upp- eller nedregleringsbud på reglermarknaden. Studien av Broberg m.fl. (2014) har även analyserat hur stor ekonomisk kompensation hushåll vill ha i utbyte mot att vara flexibla. Sett till den flexibla kapacitet hushållskunders efterfrågeflexibilitet bedöms motsvara, cirka 1 400 – 3 100 MW, är kompensationskraven legitimerade, åtminstone om den flexibla kapaciteten erbjuds på någon marknadsplats för elhandel. Styrtjänster som innebär att elanvändningen automatiskt optimeras efter elpriset kan dock vara dyra idag, vilket innebär att det främst tros vara hushåll med hög elförbrukning som utnyttjar dem och de bör därför subventioneras. En annan form av flexibilitet är att anpassa elanvändningen efter det timvarierande elhandelspriset. Den enda förutsättningen för att konsumenten ska tjäna på en sådan anpassning är att elförbrukningen mäts och debiteras på timbasis, vilket är fallet för de relativt få kunder som har valt att teckna timprisavtal. På grund av att konsumentpriset på el inte varierar särskilt mycket saknas incitament för att kunder ska vilja anpassa sin användning efter priset. Det behövs därför en mer effektiv prissättning som exempelvis förstärker volatiliteten eller gör det dyrare eller billigare att använda el vid vissa tidpunkter. / In Sweden, residential consumers account for a large share of the final electricity consumption. Their consumption patterns pose great impact on the network power peaks, especially during the winter. If residential consumers were more flexible in their consumption, peaks would be alleviated considerably and the balance between electricity supply and demand would more easily be maintained. Today, demand side flexibility is not utilized to any greater extent, except the one from energy intensive industries. De flexible capacity a single household could contribute with is of course less than within industries, but if flexible capacity from a large number of households were bundled up it would provide a considerable impact on the electricity system. At low outdoor temperatures there is an estimated potential to reach power adjustments in the size of 1 400 – 3 100 MW if the heat load in just over half of the electric heated houses in Sweden were displaced, and a few hundred more if residential consumers were flexible in their consumption of domestic electricity. According to a study by Broberg et al (2016) approximately half the population would consider to be flexible in their electricity consumption under the right circumstances. Households that use electricity for heating can be flexible through temporarily adjust the indoor temperature, or – if they heat their homes with electricity in combination with another heat source – by switching heat source. The adjustment can also be automatic if the heating system is equipped with a central control unit. If flexible capacity from a large number of households is bundled up into grid worthy demand response by a market actor, the capacity could be offered as bids on organized electricity markets. The study by Broberg et al (2014) also analysed how much compensation households require in exchange for being flexible. The compensation levels are justified with regard to the flexible capacity that can be gathered form households, 1 400 – 3 100 MW, at least as long as the capacity is sold in an organized electricity market. Services for automatic control of heating systems, where the power output is optimized after the varying electricity price, can be expensive today, which indicates that mainly households with a high electricity consumption utilize them today. Hence, they need to be subsidized. Demand side flexibility can also be to manually change consumption patterns in response to price signals. The only precondition is that the electricity consumption is measured and billed on an hourly basis, which is the case for the relatively few consumers with hourly rate agreements. The volatility of the electricity price is however subdued due to the large share of fixed surcharges, which means there is lack of incentive for consumers to adapt their consumption in response to price variations. Hence, the volatility needs to be amplified through efficient pricing.
73

Hidden symmetries and black holes in supergravity / Symétries cachées et trous noirs en supergravité

Jamsin, Ella 26 May 2010 (has links)
Upon dimensional reduction, certain supergravity theories exhibit symmetries otherwise undetected, called hidden symmetries. Not only do these symmetries teach us about the structure of the corresponding theories but moreover they provide methods to construct black hole solutions. <p><p>In this thesis, we study the hidden symmetries of supergravity theories of particular interest and how these help constructing black hole solutions in dimensions D>4. We focus on three representative cases that are the symmetries appearing upon dimensional reduction to three, two and one dimensions. They are respectively described by finite, affine and hyperbolic algebras. In the first two cases, we develop and apply solution generating techniques.<p><p>The first part of this thesis introduces the background concepts. We start with an introduction to black holes and other black objects in dimensions D>4. We present their subtleties, the known solutions and the conjectured ones. We insist on stationary axisymmetric solutions of vacuum and to the corresponding solution generating technique.<p><p>The next chapter gives an introduction to Kac-Moody algebras. These indeed play a central role in this thesis as the symmetries appearing in three, two and one dimensions are described by three types of Kac-Moody algebras called respectively finite, affine and hyperbolic.<p><p>In the second part, we first review the notion of dimensional reductions and how the hidden symmetries can be uncovered. The rest of the thesis contains three applications of these hidden symmetries.<p><p>The first two concern five-dimensional minimal supergravity. Upon dimensional reduction to three dimensions, this theory exhibits a symmetry under the exceptional finite Kac-Moody algebra g2. This 14-dimensional algebra is the smallest exceptional finite Kac-Moody algebra. We use this duality to generate solutions while focussing mainly on black strings. <p><p>After reduction to two dimensions, the symmetry becomes infinite-dimensional and is described by the affine extension of g2. Moreover, the two-dimensional theory is integrable, which allows us to develop another type of solution generating technique, hitherto applied only to vacuum gravity. In this work we generalize it to a case with matter fields.<p><p>Finally, the notion of dimensional reduction to one dimension provides the necessary intuition for the conjecture of an algebraic formulation of M-theory, candidate to the unification of all interactions, based on the hyperbolic Kac-Moody algebra e10. In the last chapter of this thesis, we study an aspect of this correspondence, namely the e10 symmetry of massive type IIA supergravity in ten dimensions.<p><p>/<p><p>On sait depuis longtemps que par un processus appelé réduction dimensionnelle, on peut faire apparaître dans certaines théories de gravitation des symétries autrement indétectées. On les appelle des symétries cachées. La mise en évidence de ces symétries non seulement nous informe sur la structure de ces théories, mais de plus elle permet d'élaborer des méthodes de construction de solutions de trous noirs. <p><p>Dans cette thèse, nous étudions les symétries cachées de certaines théories de supergravité en dimensions supérieures à quatre. Nous nous concentrons sur trois cas représentatifs que sont les symétries apparaissant après réduction à trois, deux et une dimensions. Dans les cas des symétries apparaissant à trois et à deux dimensions nous développons et appliquons des méthodes de construction de solutions. <p><p>La première partie introduit les concepts préliminaires. Nous commençons par une introduction aux trous noirs et autres objets noirs en dimensions supérieures à quatre. Nous en présentons les subtilités, les solutions connues à ce jour et celles qui ne sont encore que conjecturées. Nous insistons particulièrement sur les solutions stationnaires à symétrie axiale dans le vide et à la méthode de construction de solutions correspondante.<p><p>Le chapitre suivant présente une introduction aux algèbres de Kac-Moody. Celles-ci jouent en effet un rôle central dans cette thèse puisque les symétries apparaissant à trois, deux et une dimensions sont décrites par trois types d'algèbres de Kac-Moody appelées respectivement finies, affines et hyperboliques. <p><p>Dans la deuxième partie, nous rentrons dans le vif du sujet, en commençant par rappeler le principe des réductions dimensionnelles et la mise en évidence des différents types de symétries cachées. Les trois derniers chapitres contiennent ensuite trois applications de ces symétries cachées. <p><p>Dans deux d'entre eux, nous nous concentrons sur la théorie de supergravité minimale à cinq dimensions. Après réduction à trois dimensions, cette théorie présente un symétrie cachée sous le groupe G2 qui, avec quatorze dimensions, est le plus petit des groupes de Lie exceptionnels. Nous utilisons cette dualité pour engendrer des solutions, en nous focalisant essentiellement sur les solutions de cordes noires. <p><p>A deux dimensions, la symétrie est décrite par l'extension affine de G2. De plus, la théorie est alors complètement intégrable. Cela conduit à un autre type de méthode de construction de solutions, jusqu'alors uniquement appliquée à des théories dans le vide. Dans ce travail, nous la généralisons donc à un cas avec champs de matière. <p><p>Enfin, la notion de réduction à une dimension fournit l'intuition d'une conjecture selon laquelle la théorie M, candidate à l'unification de toutes les interactions, pourrait être reformulée en une théorie basée sur l'algèbre de Kac-Moody hyperbolique e10. Dans le dernier chapitre de cette thèse, nous étudions un aspect de cette correspondance, à savoir, la symétrie sous e10 de la supergravité massive de type IIA à dix dimensions. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
74

Développement d'une cellule SOFC de type monochambre pour la conversion en électricité des gaz d'échappement d'un moteur thermique / Development of a single chamber SOFC device for electrical energy production from exhaust gases of a thermal engine

Briault, Pauline 16 January 2014 (has links)
Le projet présenté dans ce mémoire a pour objectif de développer un système de récupération d’énergie des gaz d’échappement d’un véhicule à essence. Constitué de piles à combustible à oxyde solide (SOFC) en configuration monochambre, le dispositif doit convertir l’énergie chimique des gaz imbrûlés en électricité. Son fonctionnement en aval du catalyseur trois voies permettrait de compléter son action dépolluante tout en améliorant l’efficacité énergétique du véhicule. Par opposition aux piles SOFC dites conventionnelles, les piles SOFC monochambres ne nécessitent pas de scellement étanche entre les compartiments et fonctionnent sous un mélange gazeux composé d’hydrocarbures et d’oxygène. L’empilement en stack de plusieurs cellules est simplifié et plus compact, son intégration au cœur du pot d’échappement est donc plus simple. Ce concept a été précédemment étudié dans la littérature et le présent projet a pour but d’améliorer les performances délivrées en optimisant certains paramètres : la géométrie de pile et les matériaux d’électrodes et d’électrolyte. De plus, un mélange gazeux plus représentatif des conditions réelles a été défini et utilisé tout au long du projet. Une étude préliminaire sur les matériaux sous forme de poudre a permis de réaliser un premier choix parmi quatre matériaux de cathode et de définir les conditions de fonctionnement théoriques des cellules. Ensuite, les cellules complètes ont été mises en forme puis étudiées sous mélange gazeux. Une densité maximale de puissance de 25 mW.cm-2 à 550°C pour une cellule Ni-CGO/CGO/LSCF-CGO a ainsi pu être obtenue. / This study aims at developing a system able to recover energy from exhaust gases of a thermal engine. Composed of Solid Oxide Fuel Cells (SOFC) in a single chamber configuration, the device has to convert chemical energy of gases into electricity. Embedded in the exhaust line at the exit of the three-way catalyst, the stack of single chamber SOFC will complete the reduction of toxic gases emissions with an improvement of the vehicle energy efficiency.Unlike conventional SOFC, single chamber SOFC do not require any gastight sealing between compartments and work in a mixed atmosphere composed of hydrocarbon and oxygen. Stack assembly is thus simplified and more compact; insertion into the exhaust line is therefore easier. This concept has been previously studied in the literature and this work aims at enhancing performances through the optimisation of some parameters such as cell geometry and cell components materials.Moreover, a more representative gas mixture of actual compositions in the exhaust line has been defined and used all along this project. A preliminary study on the raw materials has allowed to make a first selection among four cathode materials and to define theoretical working conditions of our cells. Afterwards, cells have been elaborated and then studied in the selected gas mixture. A maximum power density of 25 mW.cm-2 has been obtained at 550°C for a Ni-CGO/CGO/LSCF-CGO cell.
75

Redox Active Ligands To Facilitate Reactivity From Redox Restricted Metals

Matthew C Hewitt (11197530) 29 July 2021 (has links)
The synthesis of metal-redox active ligand complexes is described, along with reactivity studies aimed at facilitating novel C-N bond forming reactions. A copper bis(iminosemiquinone) structure is characterized, analyzed and its reduction series are characterized and the reactivity of the Cu(II) bis(amidophenolate) analog is investigated with tosyl azide. The identification of the major reaction product and its characterization is detailed, with reaction sensitivities and heavily distorted x-ray diffraction single crystal structure generating a complex data set. The characterization of the isolated product is ongoing, with EPR studies aimed at identifying the radical nature of the complex. Unusual solvent effects and solubility issues have been noted with these initial EPR studies and more data is necessary before analysis can be properly attempted. An ytterbium bis(amidophenolate) complex was synthesized and its reactivity studied with aryl azides. Initial reactivities generate the first documented lanthanide tetrazenes in-lieu of the targeted ytterbium imido. Reactivities and characterization of these complexes support a stable, heavily ionic tetrazene-metal complex with no observed redox nature, UV light sensitivities, or imido azide-tetrazene equilibrium observed in various tetrazene transition metal complexes. Synthesis of a sterically blocked ytterbium imido was attempted, utilizing DMAP. Initial isolation was achieved with characterization and reactivity studies supporting the imido nature of the complex. The weak coordinating of the DMAP provided instability that proved in opposition to crystallization, however, so the imido could not be confirmed. Initial reactions using alternative steric hinderance from triphenylphosphine oxide and pyridine N-oxide prove promising to increasing the stability of the presumed ytterbium imido. Organic synthesis was performed generating a potential antibacterial agent. The synthesis of cyclopropenes was initiated as antagonists for ETR proteins in fruits and plants. The intermediates proved highly sensitive to harsh chemical conditions, which was overcome utilizing a tin-mediated Barbier allylation. The cyclopropene alcohol synthon was synthesized, though protecting group optimization is necessary.
76

Réductions hamiltoniennes en physique des plasmas autour de la gyrocinétique intrinsèque / Hamiltonian reductions in plasma physics about intrinsic gyrokinetics

De guillebon de resnes, Loic 16 September 2013 (has links)
La gyrocinétique est un modèle clef pour la microturbulence en physique des plasmas. Elle présente encore plusieurs difficultés, qui pourraient invalider ses équations. Ce rapport de thèse clarifie trois d'entre elles. Tout d'abord, une de des coordonnées causait des soucis, d'un point de vue tant physique que mathématique ; une coordonnée adéquate est introduite, qui dissipe les difficultés et explique les structures intrinsèques sous-jacentes. Ensuite, des relations de récurrence explicites sont obtenues pour tous les ordres du développement perturbatif. Enfin, en utilisant la structure hamiltonienne de la dynamique, le couplage plasma-champ électromagnétique est implémenté d'un façon plus adaptée, avec d'importantes conséquences sur les équations gyrocinétiques.Plusieurs autres résultats sont obtenus, e.g. sur l'origine de l'invariant adiabatique centre-guide, sur une transformation centre-guide minimale très efficace, ou sur un modèle hamiltonien intermédiaire entre Vlasov-Maxwell et la gyrocinétique, dont les caractéristiques de Vlasov contiennent à la fois la dynamique lente centre-guide et la dynamique rapide du gyro-angle. Diverses méthodes de réduction sont utilisées, développées ou introduites, e.g. une transformée de Lie du mouvement, un relèvement transférant les réductions de la dynamique des particules à la dynamique des champs, ou une troncature reliée à la fois à la théorie des contraintes de Dirac et à une projection sur une sous-algèbre. Outre la gyrocinétique, cela clarifie d'autres réductions hamiltoniennes en plasmas, e.g. pour une dynamique incompressible ou électrostatique, pour la MHD, ou pour des fermetures fluides avec tenseur de pression. / Gyrokinetics is a key model for plasma micro-turbulence. It still suffers from several issues, which could imply to reconsider the equations. This thesis dissertation clarifies three of them. First, one of the coordinates caused questions, both from a physical and from a mathematical point of view; a suitable constrained coordinate is introduced, which removes the issues from the theory and explains the intrinsic structures underlying the questions. Second, explicit induction relations are obtained to go arbitrary order in the perturbative expansion. Third, using the Hamiltonian structure of the dynamics, the coupling between the plasma and the electromagnetic field is implemented in a more appropriate way, with strong consequences on the gyrokinetic equations. Several other results are obtained, for instance about the origin of the guiding-center adiabatic invariant, about a very efficient minimal guiding-center transformation, or about an intermediate Hamiltonian model between Vlasov-Maxwell and gyrokinetics, where the characteristics include both the slow guiding-center dynamics and the fast gyro-angle dynamics. In addition, various reduction methods are used, introduced or developed, e.g. a Lie-transform of the equations of motion, a litfing method to transfer particle reductions to the corresponding Hamiltonian field dynamics, or a truncation method related both to Dirac's theory of constraints and to projections onto Lie-subalgebras. Besides gyrokinetics, this is useful to clarify other Hamiltonian reductions in plasma physics, e.g. for incompressible or electrostatic dynamics, for magnetohydrodynamics, or for fluid closures including moments of order two.
77

La construction pompidolienne de l'Europe face au défi de la problématique allemande (1969-1974) / The pompidolian construction of Europe facing the challenge of the German problematic (1969-1974)

Pierre, Joële 05 October 2018 (has links)
Si la France n’est plus qu’une puissance moyenne en déclin relatif, la RFA est dans une phase de take off économique et amorce un rayonnement international. Dès son investiture, Brandt lance l’émancipation de l’Allemagne. L’Ostpolitik pourrait-elle avoir la priorité pour le gouvernement fédéral sur la politique communautaire ? La menace soviétique sur l’Allemagne est à prendre très au sérieux pour Pompidou. Réunification ; Neutralisation. Face à cette situation pluriellement très préoccupante, Pompidou a besoin de l’Europe ; mais en 1969, la construction européenne est dans l’impasse. 1971, Pompidou lance son modèle de construction de l’Union Européenne : le ‘gaullisme européen’. Son atout, Edward Heath, un ‘Européen sincère’. « On œuvre en commun, même avec l’Allemagne », affirme le Président. Le traité de l’Elysée : essentialité majeure dans l’apprentissage de l’autre ; embrayage du moteur franco-allemand ; banalisation des relations franco-allemandes. Ses enjeux : Pôle monétaire européen ; Coopération politique extérieure commune (Moyen-Orient) ; Programme ambitieux de la Conférence de Paris ; Identité Européenne ; Politique extérieure commune franco-allemande face à Moscou. Mais une politique autonome européenne pouvait-elle exister pour Washington ? Nixon et Kissinger manœuvrent pour imposer le partnership atlantique aux Européens. Crises du dollar (1971, 1973) ; Condominium américano-soviétique ; Conférence sur l’énergie. Bonn s’évertue en vain à œuvrer comme médiatrice entre Paris et Washington. / While France is only a middle power in relative decline, the FRG is in a phase of economic take off and begins an international influence. Upon his nomination, Brandt launches the emancipation of Germany. Could Ostpolitik have priority for the federal government over European Community policy? The Soviet threat to Germany is to be taken very seriously for Pompidou. Reunification; Neutralization. Faced with this plurially worrying situation, Pompidou needs Europe; but in 1969, the construction of Europe is deadlocked. 1971, Pompidou launches its construction model of the European Union: 'European Gaullism'. His asset, Edward Heath, a 'sincere European'. "We work jointly, even with Germany," says the President. The Elysée Treaty: major essentiality in the learning of the other; clutch of the Franco-German engine; normalization of Franco-German relations. Its challenges: European Monetary Pole; Common foreign policy cooperation (Middle East); Ambitious program of the Paris Conference; European identity ; Franco-German Common Foreign Policy against Moscow. But could an autonomous European policy exist for Washington? Nixon and Kissinger maneuvered to impose Atlantic partnership on Europeans. Dollar crises (1971, 1973); US-Soviet Condominium; Conference on Energy. Bonn strives in vain to work as a mediator between Paris and Washington.
78

Mecanismo de Desenvolvimento Limpo e eficácia das medidas de compensação de reduções certificadas de emissões: análise de projetos aplicados à mineração

Molino, Fernanda Brusa 05 November 2013 (has links)
Made available in DSpace on 2016-04-26T20:22:18Z (GMT). No. of bitstreams: 1 Fernanda Brusa Molino.pdf: 2400362 bytes, checksum: 398405a7c8529d68f2fab1d6fff2f18e (MD5) Previous issue date: 2013-11-05 / Industrialization, that was already seen as synonymous of progress and hope of a better future for most nations, reaches the XXIth century facing many detractors and being seen as a major threat because of its voracious consumption of raw material which exhausts seas, forests, soil, subsoil and releases harmful gases that contribute to the greenhouse effect, causing the reaction of sectors of society concerned with the legacy that will be let to future generations. Among most harming sectors, are mining and related industry, whose degrading and polluting activities demonstrates the need for quality control and environmental monitoring. This study seeks to contextualize the concern about global warming and the rise of international treaties on the subject for the defense of the environment, mentioning Kyoto Protocol, Intergovernmental Negotiating Committee for a Framework Convention on Climate Change (INC/FCCC), the conferences between the parties, and also the Brazilian legislation related to the issue of climate change mitigation. The study seeks to know about the flexibility mechanisms proposed by Kyoto Protocol, aiming to achieve emission reductions by developed countries signatories. The research analyzes the Clean Development Mechanism (CDM), the Certified Emission Reductions (CER) and the efficiency of these instruments as a form of environmental compensation, highlighting the various modalities, to finish with the presentation of the carbon market and CDM related projects that help in global warming mitigation undertaken by mining sector. Among the findings, it appears that compensation measures are able to meet the recommendations of the Kyoto Protocol and to assist in combating the adverse effects of mining to the environment / A industrialização, antes sinônimo de progresso e esperança de um futuro melhor para a maioria das nações, alcança o século XXI enfrentando muitos detratores e sendo vista como grande ameaça em razão da voracidade no consumo de matéria-prima que exaure os mares, as florestas, o solo, o subsolo e libera os nocivos gases que contribuem para o efeito estufa, provocando a reação de setores da sociedade preocupados com o legado que será herdado pelas gerações futuras. Entre os setores que mais poluem está a mineração e as atividades relacionadas, cuja ação degradadora para o meio ambiente demonstra a necessidade de controle de qualidade ambiental e monitoramento. Este estudo busca contextualizar a preocupação com o aquecimento global e o surgimento de tratados internacionais sobre o tema para a defesa do meio ambiente, fazendo menção ao Protocolo de Quioto, à Convenção- Quadro das Nações Unidas sobre Mudança do Clima e às Conferências entre as partes, e também as legislações brasileiras relacionadas à questão da mitigação das mudanças climáticas. Buscam-se conhecer os mecanismos de flexibilização propostos pelo Protocolo de Quioto, visando atingir às reduções de emissão pelos países desenvolvidos signatários. A pesquisa analisa os Mecanismos de Desenvolvimento Limpo (MDL), as Reduções Certificadas de Emissões e a eficiência desses instrumentos como forma de compensação ambiental, destacando-se as várias modalidades, para finalizar com a apresentação do mercado de carbono e projetos relacionados com MDL que auxiliam na mitigação do aquecimento global empreendidos pelo setor minerário. Entre os achados, verifica-se que as medidas de compensação são capazes de atender às propostas do Protocolo de Quioto e auxiliar no combate aos efeitos adversos da mineração ao meio ambiente
79

MARKET ADOPTION AND IMPACT OF ELECTRIC ROADWAYS ON CRITERIA POLLUTANTS AND GREENHOUSE GAS EMISSIONS

Theodora Konstantinou (5930705) 16 January 2019 (has links)
<p>Traffic is inevitably a major source of air pollution, particularly in urban areas. Efforts are made towards reducing emissions by improving vehicle and fuel technology and promoting alternative, sustainable modes of transportation. Although the emergence of EVs has shown capabilities of decreasing energy use and emissions levels, the EV market is developing slowly mainly due to drivers’ range anxiety and charging time. Electric roadways (ERs) have been proposed as a solution to overcome the concerns related to EVs by converting road segments into powered lanes where vehicles can be charged as they move along the roadway. This technology has the potential to increase driving range, decrease battery size and thus, lower the weight and the cost of EVs. In this context, exploring the challenging concept of ERs comes natural. </p> <p>Since data on the market acceptance and the environmental implications on this technology are limited to non-existent, this thesis has the following objectives: 1) identify the factors that affect the short- and long-term intention to use ERs, 2) estimate the level of adoption of the ER technology and identify characteristics of the market segments and 3) assess the impact of ERs on criteria pollutants and greenhouse gas emissions based on the market adoption results.</p> <p>To achieve these objectives, a survey of the general population in Los Angeles, California was conducted, gathering 600 responses representative of gender and age in the area. Los Angeles is considered a leader in electro-mobility and thus, a natural choice for the implementation of ERs. The short-or long-term intentions to drive on ERs and purchase an EV knowing about the availability of ERs were found to be correlated and thus, were modeled simultaneously using a bivariate ordered probit model. The compatibility of the ER technology with respondents’ lifestyle and needs, respondents’ tendency towards using sustainable forms of transportation, respondents’ innovativeness and perceived environmental benefits were among the most significant variables found to affect the short-term and long-term intention to use ERs.</p> <p>The level of adoption of the ER technology and corresponding market segments were identified using a combination of Principal Component Analysis (PCA) and Cluster Analysis. Three clusters emerged from the analysis: early adopters (48.5%), mid-adopters (27.67%) and late adopters (23.83%) that differed in terms of demographics and socioeconomic characteristics, travel and EV charging characteristics and level of awareness. </p> <p>The adoption levels found were then used to estimate the emissions change due to the implementation of the ERs by 2050. Using the California Air Resources Board’s (CARB) 2017 EMissions FACtor model (EMFAC). Two scenarios were examined considering light-duty vehicles (LDVs) in a specific corridor: “with” and “without electrification” scenarios. The results suggested that the ER technology for light-duty vehicles has the potential to provide emission reductions of 4 to 24%. A sensitivity analysis was also conducted to examine the effect of speed on the results.</p> <p>Turning to the practical implications, this thesis can provide a foundational framework for the evaluation of the ER technology in terms of environmental and economic viability and set the groundwork for future research. Ultimately, the short-term and long-term intention analysis can be used as a draft guide by state and local agencies and inform their strategic short- or long- range plans for mobility. By segmenting potential users, policy makers and transport operators can be informed about the main challenges regarding the promotion of the ER technology to distinct market segments and devise ways to accelerate its adoption. The findings from the impact analysis of ERs on criteria pollutants and greenhouse gases can also inform long-range transportation plans and existing regulations and policies in California and beyond.</p> <p> </p>
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Além das reduções : a paisagem cultural da região missioneira

Stello, Vladimir Fernando January 2013 (has links)
A paisagem tem sido objeto de interesse de diversas áreas do conhecimento, entre elas a história, a geografia, a arquitetura, o planejamento urbano, as artes visuais, e, mais recentemente, a preservação do patrimônio cultural e ambiental. O rápido processo de transformação territorial que vem ocorrendo nos últimos cinquenta anos, tem colocado em risco o patrimônio cultural e ambiental das diversas comunidades. Como resposta, a valorização da paisagem cultural vem tomando impulso como referência para estas transformações, entre outras razões, por sua direta associação com a memória coletiva, as referências culturais e seu conteúdo simbólico. No Rio Grande do Sul, desde a década de 1920, se vem trabalhando na preservação dos remanescentes das reduções jesuítico-guarani como o único patrimônio a ser considerado representativo na Região Missioneira. O interesse pela preservação do patrimônio, entendendo-o como o antes, o durante e o depois das reduções, iniciou apenas nos últimos anos, quando o modo de pensar o patrimônio se ampliou, passando a se considerar que o conjunto das diversas contribuições culturais forma e enriquece a visão da Região e poderá contribuir para seu crescimento. Diante dessa constatação ampliaram-se os estudos realizados até o momento, a partir de uma visão territorial de paisagem cultural. Mais do que a preservação do patrimônio edificado, a proteção do seu legado cultural, deve contemplar as paisagens, transformadas e criadas pelos primeiros habitantes na pré-história, pelas reduções jesuítico-guarani, pelos migrantes de origem européia de finais do século XIX e do início do século XX e pelos atuais moradores da região. Deverá contemplar, também, as tradições, os saberes e os fazeres que visam auxiliar a compreensão do território. Reconhecer esses valores dará a verdadeira dimensão da importância cultural da região e promoverá o resgate das tradições destas comunidades, que vem sendo perdidas ao longo dos anos. Conservar os costumes e a memória torna mais provável a salvaguarda desta paisagem cultural de importância no contexto nacional e internacional, fortalecendo os valores de identidade das comunidades onde estes se inserem. O uso adequado de suas potencialidades, levando em consideração a diversidade cultural que a forma, poderá promover o desenvolvimento sócio-cultural e econômico sustentável da Região. Este trabalho pretende dar início ao reconhecimento dos elementos que a marcam e a tornam única, pela sua diversidade étnica e cultural, que é o testemunho da ocupação deste território marcado pelos conflitos surgidos na definição dos limites territoriais. / The landscape has been subject of interest of several areas of knowledge, among them history, geography, architecture, urban planning, visual arts and, more recently, environmental and cultural heritage preservation. The fast process of territorial transformation of the last fifty years has put in risk the environmental and cultural heritage of many communities. In response, the appreciation of cultural landscape is gaining momentum as reference for these transformations, among other reasons, for its direct association with the collective memory, the cultural references and its symbolic content. In Rio Grande do Sul, since the 1920’s, there is a work of preservation of the remnants of the Jesuit-Guaraní Reductions as the only representative heritage in the Missions Region. The interest in heritage preservation understood as the before, the during and the after of the reductions began only in recent years, when we have widened the concept of heritage. Now we take into consideration the ensemble of the many cultural contributions that shapes and greatly enriches the vision of the region, and may contribute to its growth. Considering this fact, there was an expansion on the studies to date, from a territorial perspective of cultural landscape. More than the preservation of the built heritage, the protection of its cultural legacy should contemplate the landscapes, transformed and created by the first inhabitants in prehistory, the Jesuit-Guaraní, the European migrants of the late nineteenth and early twentieth century and the current residents. It should also include the traditions and the local know-how, for they assist the understanding of the territory. Recognize these values will give the true dimension of the cultural importance of the region, and it will promote the rescue of the communities’ traditions, which has been lost over the years. Conserving the customs and the memory makes it more likely the safeguard of this cultural landscape of national and international importance, strengthening the identity values of the communities they belong to. The proper use of its potential, taking into account the cultural diversity that shapes it, will possibly promote the socio-cultural and economic sustainable development of the region. This thesis aims to initiate the recognition of the elements that mark the region and make it unique, for its ethnic and cultural diversity, testimony of the occupation of the territory marked by conflict for defining boundaries. / El paisaje ha sido objeto de interés de diversas áreas del conocimiento, entre ellas la historia, la geografía, la arquitectura, la planeación urbana, las artes visuales y, más recientemente, la preservación del patrimonio cultural y ambiental. El rápido proceso de transformación territorial que viene ocurriendo en los últimos cincuenta años, ha puesto en riesgo el patrimonio cultural y ambiental de las diversas comunidades. En respuesta, la valorización del paisaje cultural viene tomando impulso como referencia para estas transformaciones, entre otras razones, por su directa asociación con la memoria colectiva, las referencias culturales y su contenido simbólico. En Rio Grande do Sul, desde la década de 1920, se viene trabajando en la preservación de los remanentes de las reducciones jesuítico-guaraníes como el único patrimonio considerado representativo en la Región Misionera. El interés por la preservación del patrimonio, entendiéndolo como antes, durante y después de las reducciones, se inició solamente en los últimos años, cuando el modo de pensar el patrimonio se amplió y empezó z considerarse que el conjunto de las diversas contribuciones culturales forma y enriquece enormemente la visión de la Región y podrá ayudar a su crecimiento. Ante esta realidad se ampliaron los estudios efectuados hasta el momento, a partir de una visión territorial del paisaje cultural. Más que la preservación del patrimonio edificado, la protección de su legado cultural, debe contemplar los paisajes, transformados y creados por los primeros habitantes de la prehistoria, por las reducciones jesuítico-guaraníes, por los migrantes de origen europea de finales del siglo XIX y del inicio del siglo XX y por los actuales moradores de la Región. También deberá contemplar, las tradiciones, los saberes y las formas de hacer que contribuyen a la comprensión del territorio. Reconocer esos valores dará la verdadera dimensión de la importancia cultural de la región y promoverá el rescate de las tradiciones de estas comunidades, que se han ido perdiendo a lo largo de los años. Conservar las costumbres y la memoria torna más probable la salvaguarda de este paisaje cultural de importancia en el contexto nacional e internacional, fortaleciendo los valores de identidad de las comunidades donde estos se insertan. El uso adecuado de sus potencialidades, tomando en consideración la diversidad cultural que lo forma, podrá promover el desenvolvimiento socio-cultural y económico sustentable de la Región. Este trabajo pretende dar inicio al reconocimiento de los elementos que la marcan y la hacen única, por su diversidad étnica y cultural, que es el testimonio de la ocupación de este territorio marcado por los conflictos surgidos en la definición de los límites territoriales.

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