Far-ultraviolet (FUV) spectral images of Jupiter's moon Europa were obtained by the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) on 20 occasions between the years 1999 and 2015. In this thesis these data are analyzed to look for Lyman-alpha emissions from a hydrogen corona. This hydrogen corona was recently discovered in absorption, also from HST Lyman-alpha images but with Europa in transit of Jupiter, and the aim of this study is to confirm the existence of the corona also in emission. Europa's thin atmosphere is dominated by molecular oxygen, mainly produced by radiolysis and sputtering of the icy surface. Atomic hydrogen, the main target for this study, is produced by sputtering from the surface and the dissociation of H2 and H2O. It quickly escapes the gravity of Europa. To study the hydrogen corona in the spectral STIS images the data need to be processed to remove the other Lyman-alpha contributions to the image. These other contributions include emissions from the geocorona, emissions from the interplanetary medium (IPM), dark current in the detector and sunlight reflected from the surface of Europa. To estimate the contribution to the image from the hydrogen corona, a basic model of the expected emissions from the corona is developed. By fitting this model to the processed STIS data values of the hydrogen density and the surface Lyman-alpha albedo of the moon are obtained. The results confirm the presence of a hydrogen corona, with varying densities between the different observations but generally about twice as large as the results from the previous study. The uncertainty for the results is however large and there is a clear correlation between hydrogen density and background level in the image, for which the reason is poorly understood. No hemispheric variability or connections to the true anomaly of the moon are found, but the hydrogen density seems to be increasing during the time of the observations. The results for the albedo is consistent with previous results, indicating a lower albedo on the leading than on the trailing hemisphere.

Io is the innermost Galilean moon of Jupiter and is considered the most volcanically active body in our solar system. With the help of the Hubble Space Telescope’s (HST) on-board Space Telescope Imaging Spectrograph (STIS), far-ultraviolet (FUV) images of Io have been captured for the past 20 years. The final goal of this project is to study the sulphur dioxide (SO2) distribution and volcanic activity on Io in FUV data taken in 1997/98 and 2013/14. The method used concerns the conversion of spectral Lyman-α intensity to SO2 density using algorithms implemented in MATLAB. As a result the SO2 distribution and volcanic activity on Io were determined and compared between the data collections. We found that the SO2 was higher in the images from 1997/98 compared to 2013/2014.

De la religion à la science, la quête de compréhension de notre place dans l’univers est l’un des moteurs fondamentaux du progrès humain. Depuis la découverte de la première exoplanète autour d’une étoile de la séquence principale au milieu des années 1990, le nombre de systèmes exoplanétaires a explosé pour atteindre plusieurs milliers. Nous avons même réalisé des études approfondies des atmosphères de nombreux mondes lointains, ce qui nous a permis de découvrir la diversité, jusqu’alors insondable, des planètes qui existent dans la galaxie. Pour comprendre la place de notre propre système solaire dans le contexte de la population plus large des exoplanètes, il est d’abord essentiel de comprendre la diversité des exoplanètes elles- mêmes. La spectroscopie spatiale à basse résolution a toujours été l’outil de choix pour sonder les atmosphères des exoplanètes et comprendre la physique et la chimie qui régissent leur formation et leur évolution. Au cours des deux ans et demi qui ont suivi son lancement, j’ai contribué aux études des atmosphères d’exoplanètes avec JWST couvrant tout l’espace des paramètres de la population des exoplanètes. Cette thèse contient quatre de ces études, y compris certaines des toutes premières observations d’exoplanètes avec le «Near Infrared Imager and Slitless Spectrograph» (NIRISS) du JWST. Dans le premier travail, j’ai conçu et testé une méthode pour estimer la «fonction d’étalement de point» (PSF) bidimensionnelle d’une observation avec le mode SOSS (Single Object Slitless Spectroscopy) du NIRISS, qui est l’un des principaux modes d’observation des exoplanètes du JWST. Ces PSFs sont une donée critique pour une méthode d’extraction spectrale spécialisée conçue pour traiter les défis techniques spécifiques posés par les observations SOSS. Nous démontrons ensuite que ces PSF empiriques permettent d’obtenir des spectres d’atmosphère plus fidèles que les modèles par défaut. Dans le second projet, nous présentons l’une des toutes premières observations d’exoplanètes avec JWST NIRISS/SOSS. Ces observations du transit de l’exoplanète WASP-96 b, qui est une Saturne-chaude, montrent des signatures claires de l’absorption de H2O et de K à des abondances à peu près solaires. De plus, nous détectons une pente vers les longueurs d’onde les plus bleues de notre spectre, qui pourrait s’expliquer soit par la diffusion Rayleigh de petites particules d’aérosols, soit par les ailes élargies par la pression de l’élément Na. La possibilité de la diffusion d’aérosols est particulièrement intrigante car les observations précédentes avec Hubble, entre autres, ont conclu v que la haute atmosphère de WASP-96 b n’avait pas d’aérosols, malgré les travaux théoriques indiquant qu’elle devrait être uniformément nuageuse. Le troisième travail présente un spectre de transmission JWST NIRISS/SOSS de l’unique planète ultra-chaude LTT 9779 b; la seule planète connue dans le désert de Neptunes chaudes à avoir conservé une atmosphère primordiale. Notre spectre présente des caractéristiques atténuées qui, combinées à la structure intérieure et aux modèles de synthèse de population, nous permettent de conclure que la planète possède une atmosphère au terminateur qui est nuageuse et de haute métallicité. Un scénario de haute métallicité est cohérent avec les tendances générales dans la population des exoplanètes, ainsi que dans le système solaire. De plus, s’ils sont advectés sur le côté jour, les nuages du terminateur que nous trouvons fournissent une explication naturelle à l’albédo élevé précédemment déduit pour cette planète. Nous supposons que ces nuages peuvent faire partie d’une boucle de rétroaction positive qui sert à diminuer l’efficacité de la perte d’atmosphère sous le rayonnement intense de son étoile hôte, et à aider la survie de LTT 9779 b dans le désert de Neptunes chaudes. Enfin, nous revenons à LTT 9779 b avec l’étude d’un spectre d’éclipse qui s’étend de l’ultraviolet à l’infrarouge. En combinant les éclipses de NIRISS/SOSS avec des données d’archives ainsi que des observations inédites utilisant les capacités ultraviolettes de Hubble, nous concluons que l’albédo élevé de LTT 9779 b est probablement dû à la réflexion des nuages de MgSiO3 et confirmons que sa structure de température du côté jour n’est pas inversée. Nous entreprenons ensuite une analyse comparative de LTT 9779 b dans le contexte plus large des Jupiters ultra-chaudes, qui ont des températures comparables à LTT 9779 b mais des côtés jours systématiquement dépourvus de nuages et des structures de température inversées. De cette manière nous faisons les premiers pas pour réconcilier cette planète inhabituelle avec la population plus large des mondes ultra-chauds. Ces travaux, ainsi que les ∼20 autres auxquels j’ai contribué au cours de mon doctorat, dé- montrent les capacités inégalées du JWST pour la caractérisation des atmosphères des exoplanètes. Chaque nouvelle observation nous rapproche un peu plus de la découverte des origines de la di- versité de la population des exoplanètes, ainsi que des différences et similitudes fondamentales entre les différentes «classes» de planètes. Cette thèse met en lumière les contributions que j’ai apportées à cette entreprise au cours de mon doctorat. Le JWST a sans aucun doute fait passer de nombreuses régions de la population des exoplanètes du statut de frontières ambitieuses à celui de véritables cibles d’observation et, par conséquent, la prochaine décennie sera certainement l’une des plus transformatrices de l’histoire de la science exoplanétaire. / From religion to science, the quest to understand our place in the universe is one of the fundamental drivers of human progress. Since the discovery of the first exoplanet around a main sequence star in the mid-1990s, our current count of exoplanetary systems has exploded to several thousands. We have even performed in-depth studies of the atmospheres of many distant worlds, yielding insights into the previously unfathomable diversity of planets that exist in the galaxy. In order to understand our own solar system’s place in the context of the wider population of exoplanets, it is first essential to understand the diversity of exoplanets themselves. Low-resolution spectroscopy from space has historically been the tool of choice to probe exoplanet atmospheres and gain insights into the physics and chemistry that govern their formation and evolution. In the nearly two and a half years since its launch, I have contributed to JWST atmosphere studies spanning the full parameter space of the exoplanet population. This thesis contains four of these studies, including some of the very first exoplanet observations with JWST’s Near Infrared Imager and Slitless Spectrograph (NIRISS). In the first work, I designed and tested a method to estimate the two-dimensional point spread function (PSF) of an observation with NIRISS’s Single Object Slitless Spectroscopy (SOSS) mode, which is one of the key observing modes for JWST exoplanet observations. These PSFs are a critical input to a specialized spectral extraction method designed to deal with specific technical challenges posed by SOSS observations. We then demonstrate that these empirical PSFs result in higher-fidelity atmosphere spectra than default models. The second project presents one of the first-ever exoplanet observations with JWST NIRISS/SOSS. These transit observations of the hot-Saturn exoplanet WASP-96 b show clear signatures due to absorption of H2O and K at roughly solar abundances. Moreover, we detect a slope towards the bluest wavelengths of our spectrum, which could either be explained by Rayleigh scattering from small aerosol particles or the pressure-broadened wings of a Na feature. The aerosol scattering possibility is particularly intriguing as previous observations with Hubble and ground-based facilities have concluded WASP-96 b’s upper atmosphere to be aerosol free, despite theoretical work indicating that it should be uniformly cloudy. The third work presents a JWST NIRISS/SOSS transmission spectrum of the unique ultra-hot- Neptune LTT 9779 b; the only known planet within the hot-Neptune desert to have retained a primordial atmosphere. Our spectrum displays muted features which, when combined with interior vii structure and population synthesis models, allows us to conclude that the planet has a cloudy and high-metallicity terminator atmosphere. A high-metallicity scenario is consistent with broader trends in the exoplanet population, as well as in the solar system. Moreover, if advected onto the dayside, the terminator clouds that we find provide a natural explanation for the high albedo previously inferred for this planet. We posit that these clouds may be part of a positive feedback loop which serves to decrease the efficiency of atmosphere loss under the intense radiation of its host star, and aid LTT 9779 b’s survival in the hot-Neptune desert. Finally, we return to LTT 9779 b with the study of an ultraviolet-to-infrared eclipse spectrum. Combining eclipses from NIRISS/SOSS with archival data as well as previously unpublished observations leveraging Hubble’s ultraviolet capabilities, we conclude that the high albedo of LTT 9779 b is likely caused by reflection from MgSiO3 clouds and confirm that its dayside temperature structure is non-inverted. We then undertake a comparative analysis of LTT 9779 b within the broader context of ultra-hot-Jupiters; which have comparable temperatures to LTT 9779 b but systematically cloud-free daysides and inverted temperature structures — thereby taking the first steps to reconcile this unusual planet with the broader population of ultra-hot worlds. These works, as well as the ∼20 others to which I have contributed over the course of my PhD, demonstrate the unparalleled capabilities of JWST for the characterization of exoplanet atmospheres. Every new observation brings us one step closer to uncovering the origins of the diversity of the exoplanet population, as well as the fundamental differences and similarities between different “classes” of planets. This thesis highlights the contributions I have made to this endeavour during my PhD. JWST has undoubtedly moved many regions of the exoplanet population from aspirational frontiers to genuine observational targets, and as a result, the next decade will surely be one of the most transformative in the history of exoplanetary science.

Increased oil prices and environmental issues have increased a need of loweringthe emissions from and the fuel consumption in heavy construction machines. Anatural solution to these issues is a lowered input power through downsizing ofthe engine. This implies a demand on higher transmission efficiency, in order tominimize the intrusion on vehicle performance. More specifically, alternatives tothe conventional torque converter found in heavier applications today, must beinvestigated. One important part of this is the task of controlling the transmissionwithout jeopardising the advantages associated with the torque converter, such asrobustness and controllability.In this thesis, an alternative transmission concept for a backhoe loader is investigated.The studied concept is referred to as a 2-mode Jarchow power-splittransmission, where a mechanical path is added to a hydrostatic transmission inorder to increase transmission efficiency. The concept is evaluated in computerbased simulations as well as in hardware-in-the-loop simulations, where a physicalhydrostatic transmission is exposed for the loads caused by the vehicle duringvarying conditions. The loads are in turn simulated according to developed modelsof the mechanical parts of the vehicle drive line.In total, the investigated concept can be used instead of the torque converterconcept, if the hydrostatic transmission is properly controlled. The results alsoshow that there is a high possibility that the combustion engine in the backhoeloader can be downsized from 64 kW to 55 kW, which would further increase thefuel savings and reduce the emissions.

Sverige planerar för en av de största infrastrukturinvesteringarna någonsin i Sveriges historia. I fokus står en ny höghastighetsjärnväg mellan Stockholm, Göteborg och Malmö som ska möjliggöra resor på två till två och en halv timme mellan städerna. Runt denna investering finns en ambition att samla andra samhällsbyggande åtgärder, som ökat bostadsbyggande och förbättringar i lokal och regional kollektivtrafik, för att genom en samordnad planering få ut så stora nyttor som möjligt. För detta ändamål har regeringen tillsatt den statliga utredningen Sverigeförhandlingen. En viktig del av deras arbete är att få fram en finansieringslösning för den nya statliga transportinfrastrukturen där medfinansiering från kommuner, regioner och andra aktörer står för en betydande andel. Idén kring medfinansiering är baserad på att aktörerna ska bidra till finansieringen som motsvarar de nyttor transportinfrastrukturen bidrar till. Alltså måste det gå att uppskatta att på förhand hur mycket nyttor som uppstår och vad de är värda. Sverigeförhandlingen har valt klassificera nyttorna i sex kategorier där ”social nyttor” är en av dessa. Däremot finns ingen etablerad metodik för att uppskatta dessa. Det här examensarbetet undersöker vilken social påverkan transportinfrastrukturen ger upphov till. Detta görs genom att studera samband mellan tillgänglighet, alltså hur transportinfrastrukturen ger möjlighet för människor att nå olika målpunkter, och ett antal sociala förhållanden. Tillgänglighetsmåttet valdes utifrån studier av tidigare forskning samt etablerade modeller för uppskattning av andra nyttor av transportinfrastruktur. För att veta vilka sociala förhållanden som är intressanta att undersöka har en studie av Svensk och internationell litteratur på området genomförts. Sambandsanalysen bygger på statistiska metoder där data för Sveriges kommuner används. Metoden ger möjlighet till att identifiera samvariation mellan tillgänglighet och sociala förhållanden men är inte tillräcklig för att säkerställa att tillgänglighet är en orsak till de sociala förhållandena. Resultaten tyder på att tillgänglighet har statistiskt signifikanta samband med ett antal indikatorer för sociala förhållanden. Exempel på två av dessa är ungdomsidrottande och andelen barn som går i förskola. Det visade sig att de flesta av de sociala förhållanden som har signifikanta samband med tillgänglighet har en samvariation som tyder på att tillgänglighet korrelerar med positiva sociala förhållanden. Detta tyder på att tillgänglighet kan ha samband med faktorer som kan tolkas som sociala nyttor. Dock kan inget sägas om tillgänglighet är en orsak till detta eller om det är någon icke studerad orsak som ger upphov till detta. Dessutom påverkas tillgänglighetsmåttet av andra faktorer än enbart tillgång till transportinfrastruktur och därför går det inte utifrån dessa samband att säkert säga att de beror på transportsystemet. För att sociala nyttor ska kunna kvantifieras och ligga till grund för medfinansiering krävs vidare studier. En viktig uppgift är att med hjälp av bättre data och mer avancerade metoder få fram bättre uppskattningar av sambanden samt orsaksrelationerna. Det krävs också studier för hur sociala nyttor ska värderas i monetära termer ur ett samhällsekonomiskt perspektiv. / Sweden is currently planning for one of its largest investments in transport infrastructure ever. A cornerstone in the project is a new high speed railroad between Stockholm, Gothenburg and Malmö. A considerable portion of the funding will consist of co-funding from municipalities, regions and private actors that will benefit from the infrastructure. The amount of co-funding is based on the total benefits that each actor will receive. Therefore these benefits must be able to be quantified. This report aims to study relationships between transport infrastructure and a number of social consequences that previous research has indicated being interesting. The method used is based on econometric methods that enable identification of statistical relationships using a simple linear model. This requires measures of transport infrastructure and indicators for social well-being which are chosen through a study of literature and established models quantifying wider economic benefits from transport infrastructure.The report suggests that a gravitybased accessibility measure is suitable for quantifying transport infrastructure in this context. The results from the econometrical model ssuggest that there are several significant relationships between accessibility and social well-being. In general accessibility seems to correlate with positive social consequences. However it is likely that endogeneity is biasing the results and make it difficult to draw any conclusions on causal relationships. It is stated that further research studying these relationships more carefully with better adapted data for the purpose is required to be able to obtain quantified estimates that can be used in co-funding of transport infrastructure.

Este trabalho caracterizou os siltitos do Grupo Itararé, rocha branda proveniente da amostragem de pedreira localizada nas proximidades de futuro empreendimento brasileiro, o Trem de Alta Velocidade. Objetivou entender as causas da pronunciada e rápida alteração da rocha intacta, e simular, em condições controladas de laboratório, a degradação hidromecânica causada pela simples variação da umidade relativa do ar. Para tal, estabeleceu-se técnica de amostragem de testemunhos por meio da extração via seca com ar-comprimido, e processo de intemperismo artificial, composto por 4 ciclos de 2 etapas (secagem e umedecimento). O processo se deu em dessecadores, sendo a variação da umidade ocasionada pela técnica do vapor e sílica gel. O acompanhamento da degradação dos corpos de prova efetuou-se com duas técnicas não-destrutivas de propagação de ondas: o pulso ultrassônico e a excitação por impulso (sistema Sonelastic). Em paralelo, realizou-se a caracterização geotécnica dos siltitos em umidade natural, com ensaios mineralógicos, físicos, físico-mecânicos, físico-químicos e de alteração laboratorial. Por meio desta metodologia, foi possível estimar as minorações do módulo de deformabilidade e da resistência, além das causas físico-químicas da degradação. / This work characterized the siltstones of the Itararé Group, a soft rock sampled in a quarry located near a future Brazilian venture, the High Speed Train. It aims at understanding the causes of the pronounced and fast changes of the intact rock, and simulate in controlled laboratory conditions the hydro degradation process caused by simple variation of relative air humidity. Dry sampling technique with compressed air was used to extract samples from blocks, and the process of artificial weathering consisted on 4 cycles of 2 steps (drying and wetting). The process occurred in desiccators, where moisture variation was caused by the vapor technique and silica gel. The monitoring of the specimens degradation was performed with two non-destructive wave propagation techniques: the ultrasonic pulse and the impulse excitation (Sonelastic system). A geotechnical characterization of the siltstones in natural moisture condition was made in parallel, consisting on mineralogical, physical, physical-mechanical, physical-chemical and durability tests. By this methodology, it was possible to estimate the mitigation of the deformability modulus and strength besides the physical- chemical causes of degradation.

Este trabalho tem como objetivo principal direcionar a tomada de decisões para a escolha dos diferentes parâmetros que envolvem o alinhamento horizontal e vertical do projeto geométrico ferroviário de trens de alta velocidade (TAV) e de longo percurso, bem como descrever conceitos teóricos para parâmetros de segurança e conforto, baseados em normas internacionais. A pesquisa se desenvolve através de consultas em revistas especializadas, artigos, publicações, normas técnicas e livros. Pela escassez de dados em língua nacional e material bibliográfico desatualizado, as pesquisas se concentram essencialmente em material internacional. Apesar do Brasil ser um dos países em desenvolvimento com maior ascensão no cenário global, tem apresentado, nas últimas décadas, sérios problemas de infra-estrutura devido a uma distribuição desequilibrada na área de transportes, com altíssima concentração no modo rodoviário, com aeroportos e rodovias operando acima da capacidade satisfatória, além de um leque limitado de alternativas de transporte. Devido à falta de investimentos no setor ferroviário, grande parte da malha ferroviária brasileira tornou-se inoperante ou até mesmo inexistente, resultando numa enorme diminuição da mão de obra qualificada e formação acadêmica nesse ramo. Como conseqüência, os estudos relacionados ao projeto ferroviário também foram afetados diretamente. Nesse contexto, é importante que se resgate normas, publicações, especificações técnicas e experiências adotadas em outros países com sólidas tradições ferroviárias, de modo a incorporar em nossa formação acadêmica tais conceitos, como é um dos objetivos dessa dissertação. / This dissertation has as main objective to guide in taking decisions for the selection of different parameters which involve the horizontal and vertical railway geometric design of high speed (HST) and long distance trains as well as theoretical concepts for describing security parameters and comfort, based on international standards. The research is developed through consultations in specialized magazines, articles, publications, standards and technical books. Due to the scarcity of data in the national language and outdated library materials, the research focuses primarily on international material. Although Brazil is a developing country with one of the highest rises in the global scene, the country has faced in recent decades serious infrastructure problems due to an uneven distribution in the area of transport, with high concentration in the road, and airports and roads operating above satisfactory capacity, resulted by a limited range of transportation alternatives. Due to the lack of investment in the railway sector, much of the Brazilian railway system became inoperative or even nonexistent, resulting in a tremendous decrease of skilled labor and academic training in this field. As a result, studies related to the railway project have also been directly impacted. In this context, it is important to rescue standards, publications, experiences and technical specifications adopted in other countries with strong tradition in railways in order to incorporate these concepts into our academic formation, which is one of the purposes of this dissertation.

Les galaxies elliptiques ne sont des objets astronomiques très simples qu'en apparence: leur forme parfaitement régulière et ellipsoïdale est davantage le vestige d'une histoire tumultueuse semée d'interactions gravitationnelles avec d'autres galaxies plutôt que le signe d'un stade primitif dans leur vie. En effet, ces deux dernières décennies ont révélé la complexité de ces objets au niveau de leur cinématique interne, et surtout récemment avec le spectrographe intégral de champ SAURON qui a permis de dresser la structure bidimensionnelle de la vitesse de nombreuses galaxies elliptiques. La compréhension de la formation et de l'évolution de ces objets est un enjeu majeur de l'astrophysique contemporaine. La théorie hiérarchique de formation et d'évolution des galaxies, selon laquelle une galaxie est le résultat de nombreuses interactions et de fusions d'objets moins massifs, est à l'heure actuelle la mieux soutenue par les observations. Ainsi, elle permet de rendre compte de structures complexes telles les galaxies à coeur cinématiquement distinct, dans lesquelles on observe un brusque changement dans la courbe de rotation. Certains de ces objets montrent même une inversion dans le sens de rotation de la partie interne. De nombreuses études ont été réalisées pour comprendre les mécanismes de formation de ces coeurs, et la plupart d'entre elles semblent nécessiter l'apport d'un corps externe voire la fusion de deux galaxies. Dans ce travail nous réalisons dans un premier temps un catalogue de ces objets, afin d'en dégager les conclusions majeures. Dans un second temps nous présentons une méthode permettant d'extraire la signature orbitale de ces structures découplées en utilisant une modélisation dynamique de Schwarzschild . Nous appliquons cette méthode à trois objets dont nous disposons des données intégrales de champ, et tentons d'en extraire les principaux points communs. Finalement nous soulignons la valeur de cette méthodologie pour contraindre les modèles hiérarchiques de formation.

L'objectiu central de la tesi és estudiar els processos que permeten aconseguir un desenvolupament local a llarg termini de les ciutats mitjanes a partir de la implantació d'una gran infrastructura com el Tren d'Alta Velocitat (TAV). Es parteix de la hipòtesi que el desenvolupament local urbà a partir del TAV depèn de factors objectius i de factors subjectius (dels subjectes), uns factors que prenen una forma particular en el desenvolupament de les ciutats mitjanes. La tesi es divideix en una primera part teòrica i segona de més aplicada.Diversos autors han arribat a la conclusió que la relació tradicional que s'ha donat entre les infrastructures de transport i territori parteix d'uns paradigmes deterministes, que s'exemplifiquen amb una relació de "causa-efecte". Per aquest motiu, s'han criticat els estudis sobre els efectes socioeconòmics de les infrastructures de transport, així com el mateix concepte d'"efecte". Aquesta crítica es repeteix els estudis sobre el TAV i les ciutats mitjanes, que arriben a la conclusió que el desenvolupament econòmic no és un fet automàtic i que no es poden predir les conseqüències a mig i llarg termini del TAV.El desenvolupament local a partir del TAV, doncs, estaria relacionat amb tres elements principals. En primer lloc, entendre que la ciutat -i el territori- és un fenomen complex i, com a tal, cal abordar-lo des de la teoria dels sistemes complexos. En segon lloc, la gran infrastructura ha de convertir-se en un recurs endogen (interconnexió amb la xarxa local d'actors i territorialització en el milieu de la ciutat) per a que pugui contribuir al desenvolupament. En tercer lloc, la dinàmica de governance dels actors és primordial, i es divideix en la gestió interna de la xarxa local (projecte local) i la gestió multinivell de les administracions.En base als referents teòrics, es construeix una metodologia per avaluar el grau de desenvolupament local que ha comportat el TAV en tres ciutats mitjanes de l'arc mediterrani europeu, Lleida, Avinyó i Novara, situades respectivament a Espanya, França i Itàlia. La metodologia preveu l'estudi d'aspectes tècnics de la ciutat com els de transport (Posició territorial de la ciutat a partir del TAV, Característiques de l'estació TAV), urbanístics (Model urbanístic a escala municipal/urbana, Model urbanístic a escala de l'estació) i econòmics (Diferents projectes econòmics de la ciutat relacionats amb el TAV). També preveu l'estudi d'aspectes organitzatius externs (Els agents supralocals i els seus projectes, Grau de conflictivitat i cooperació en les relacions dels agents locals i supralocals) i interns (Capacitat de creació d'un projecte de ciutat a partir del TAV, Agents que participen en el projecte local i la seva dinàmica, Àmbit territorial dels projectes). Finalment s'efectua una avaluació del procés i dels resultats del desenvolupament local.Com a conclusió es demostra que el procés de desenvolupament local a partir de les grans infrastructures de transport depèn, en bon part, de la capacitat de governance. Depèn, per un cantó, de la capacitat dels agents locals d'elaborar un projecte de desenvolupament i liderar unes estratègies d'aprofitament i, de l'altre, de la capacitat dels agents del territori (estatals, regionals, locals) de crear aliances i cooperació per planificar la infrastructura de transport. Finalment es presenten un seguit de recomanacions a les ciutats que volen planificar l'arribada del TAV per a que contribueixi a un desenvolupament amb les característiques d'eficàcia, sostenibilitat, productivitat i equitat. / The central goal of this thesis is to study the processes that allow to achieve a long-term local development of medium-sized towns from the implantation of a great infrastructure like High Speed Train (HST). Is started from the hypothesis that the urban local development from the HST depends on objective factors and on subjective factors (of subjects), some factors that take a particular form in the development of medium-sized towns. The thesis is divided into a theoretical part and a second applied part. Several authors have concluded that the traditional relationship between transport infrastructures and territory departs of some deterministic paradigms, such a cause-effect relation. For this motive, they have criticized the studies of socioeconomic effects of transport infrastructures, as well as the concept of "effect". These criticisms are made as well to the relation between HST and medium-sized towns. Many authors conclude that economic development is not an automatic fact and that consequences of HST can not be predicted in half and long term.Local development from the HST, then, would be related to three main elements. First, we need to understand that city and territory are complex phenomenons and, for this, it is necessary to approach them from the theory of complex systems. Second, the great infrastructure has to become an endogenous resource (interconnection with the local network of actors and territorialisation in the milieu of the city) to contribute to development. Third, dynamics of governance between actors is fundamental. It can be divided into internal management of local network (local project) and multilevel management of administrations.With regard to theoretical referents, a methodology is constructed to estimate the degree of local development that has entailed HST in three medium-sized towns of European Mediterranean arch, Lleida, Avingnon and Novara, placed respectively in Spain, France and Italy. The methodology proposes the study of technical aspects of the city like those of transport (Territorial position of the city in HST system, Characteristics of HST station), urban planning (Municipal urban planning model, Urban planning model at scale of station) and economy (Different economic projects of the city related to HST). It also proposes the study of external organizational aspects (Supra-local agents and their projects, Degree of conflictivity and cooperation between local and supra-local agents) and internal (Capacity of creation of a local project from HST, Agents that participate in local project and their dynamics, Territorial area of projects). Finally it is made an evaluation of process and results on local development.As a conclusion it is demonstrated that process of local development from great transport infrastructures depends, basically, on the capacity of governance. It depends, on one side, on the capacity of local agents to elaborate a development project and to lead some strategies and, on the other side, on the capacity of territorial agents (state, region, local) to create alliances and cooperation to planning the transport infrastructure. Finally, some recommendations are presented to the cities that want to plan the arrival of the HST and want to produce development with characteristics of efficiency, sustainability, productivity and equity.

Hypersonic flow is both fascinating and intriguing mainly because of presence of strong entropy and viscous interactions in the flow field. Notwithstanding the tremendous advancements in numerical modeling in the last decade separated hypersonic flow still remains an area where considerable differences are observed between experiments and numerical results. Lack of reliable data base of surface static pressures with good spatial resolution in hypersonic separated flow field is one of the main motivations for the present study. The experiments in hypersonic shock tunnels has an advantage compared to wind tunnels for simulating the total energy content of the flow in addition to the Mach and Reynolds numbers. However the useful test time in shock tunnels is of the order of few milliseconds. Hence in shock tunnel experiments it is essential to have pressure measurement devices which has special features such as small in size, faster response time and the sensors in array form with improved spatial resolutions. Micro Electro Mechanical Systems (MEMS) is an emerging technology, which holds lot of promise in these types of applications. In view of the above requirement, MEMS based pressure sensor array was developed to measure the static pressure distribution. The study is comprised of two parts: one is on the development of MEMS based pressure sensor array, which can be used for hypersonic application and other is on experimental static pressure measurement using MEMS based sensors in separated hypersonic flow over a backward facing step model. Initially a static pressure sensor array with 25 sensors was developed. The static calibration of sensor array was carried out to characterize the sensor array for various characteristic parameters. The preliminary experimental study with cluster of 25 MEMS sensor array mounted on the flat plate did not provide reliable and repeatable results, but gave valuable inputs on the typical problems of using MEMS sensors in short duration hypersonic ground test facilities like shock tunnels. Incidentally, to the best of our knowledge this is first report on use of MEMS based pressure sensors in hypersonic shock tunnel. Later cluster of 5 sensor array was developed with improved electronic packaging and surface finish. The experiments were conducted with flat plate by mounting 5 sensor array shows good agreement in static pressure measurement compared with standard sensors. In the second part of the study a backward facing step model, which simulates the typical gasdynamic flow features associated with hypersonic flow separation is designed. Backward facing step model with step height of 3 mm was mounted with sensor array along the length of model. Just after the step, static pressure measurements were carried out with MEMS sensors. It is important to note that, in the space available in backward facing step model we could mount only one conventional Kulite pressure transducer. The experiments were conducted at Mach number of 6.3 and at stagnation enthalpy of 1.5 MJ/kg in hypersonic shock tunnel (HST-5) at IISc. Based on the static pressure measurement on backward facing step, the location of separation and reattachment points were clearly identified. The static pressure values show that reattachment of flow takes place at about 7 step heights. Numerical simulations were carried out using commercial CFD code, FLUENT for flat plate and backward facing step models to compliment the experiments. The experimental tests results match well with the illustrative numerical simulations results.