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The principie of this research answers to the interest to procure a value for silence. This argument was added to the expectation generated by the "Documento básico de Protección Frente al Ruido (DB-HR) del Código Técnico de la Edificación (CTE)," which incremented the profit demands in buildings and from here comes the next questions: How much do people agree to pay for an acoustically insulated dwelling? Does the willingness to pay overcome the increment in the cost of the building systems which come from the normativity previously mentioned? The work hypothesis states that the cost of the technique-constructive applications included in the CTE to improve the acoustic comfort of housing is lower than the benefits which individuals perceive and convey in their willingness to pay for acquiring a house with these characteristics . The aim is to utter that for the new residential market in Barcelona, the willingness to pay for occupy a house which gives a major acoustic comfort exceed the cost of the implementation of the most restrictive insulated systems . This thesis is structured in two parts : theoretic and empiric. The first one includes the acoustic concepts and microeconomics applied in the valuation environmental goods . The context contemplates the importance of silence , which does not have a value, or if it would have it, in place of a house with a major acoustic insulation; it cannot satisfy the demand in a while. In this situation the contingent valuation method is an instrument that beyond of its interpretation generaliy provides possible answers to the questions requested previously. As for the empiric one, it is estimated the possible over costs related to the ¡ncrement in the isolation and the amount of related profits given to this variation. The proposing intended to create a hypothetical market for people to expose their preferences . This is one of the main attributes of this study. It meant to organize and get through the acoustic simulation of a dwelling which rose up the diverse acoustic isolation levels and the main conditions posed by the barcelones real estate market. The outcomes gotten display the significance of the research presented in diverse situations. The first one is the analysis of the economic impact in the acoustic contamination, discovered in the willing to pay for residing in more acoustic dwellings. This analysis may be the information source for the public and private agents over the trade -off that is generated when the building techniques improve increasing the habitability of dwelling. Taken into consideration the methodology, the relevance is the designed scenery and the evaluation of the benefits related to the DB-HR launching. With the right incentive, people think over those complex situations which affect them (the advantages to improve the acoustic conditions of a house) and it is demonstrated that the contingent valuation method provides reliable information to perform the analysis of public policies. Finally, the econometric models display products which recommend that the ordered logit matches better the questioning format handle and allots reliable valuations in the willingness to pay. / El origen de la investigación responde al interés de obtener un valor para el silencio. Este argumento se sumó a la expectación generada por la implementación del Documento básico de Protección Frente al Ruido (DB-HR) del Código Técnico de la Edificación (CTE), en él se aumentaron las exigencias prestacionales en las edificaciones y de aquí manan las siguientes preguntas ¿cuánto están las personas dispuestas a pagar por habitar una vivienda más aislada acústicamente? ¿Está disposición supera el incremento en los costes de los sistemas constructivos que se desprenden de la citada normativa? La hipótesis de trabajo plantea que el coste de desarrollo de las técnicas constructivas indicadas por el CTE, que mejoran el confort acústico de las viviendas, es menor que el beneficio que los individuos perciben y expresan en su disposición a pagar por adquirir una vivienda con estas características. El objetivo es demostrar, para el mercado residencial de nueva planta barcelonés, que la disposición de las personas a pagar por habitar una vivienda que proporcione un mayor confort acústico, supera los costes de implementar sistemas de aislamiento más restrictivos. La tesis se estructura en dos partes: teórica y empirica. En la primera se abordan tanto conceptos de acústica, como de microeconomía aplicada en la valoración de bienes ambientales. El contexto supone la valoración de un bien (el silencio) que no tiene mercado, o de tenerlo, en el caso de la vivienda con mayor aislamiento, no puede satisfacer la demanda en el corto plazo. En estas situaciones la técnica de valoración contingente es un instrumento que más allá de sus interpretaciones, en general da respuestas viables a las preguntas anteriores . En la parte empírica se estiman los probables sobrecostes asociados al incremento en el aislamiento y la cuantificación de los beneficios relacionados a este cambio. El planteamiento implicó generar un mercado hipotético para que las personas revelasen sus preferencias. Es aquí donde se presenta uno de los principales atributos de la investigación: preparar y utilizar la simulación acústica de una vivienda que cumple con distintos niveles de aislamiento y que incluye las principales características ofrecidas por el mercado inmobiliario barcelonés. Los resultados obtenidos indican que la relevancia de esta investigación se presenta en distintos ámbitos. El primero es el análisis del impacto monetario de la contaminación acústica, revelado en la disposición a pagar por habitar viviendas más aisladas. Este análisis puede ser fuente de información para los agentes públicos y privados sobre el trade-off que se genera cuando se mejoran los procesos de edificación que incrementan la habitabilidad de las viviendas. En términos metodológicos, lo relevante es el escenario diseñado y la evaluación de los beneficios que se asocian a la implantación del DB-HR. Con incentivos adecuados, los individuos opinan sobre cuestiones complejas que les afectan (las ventajas de mejorar las condiciones acústicas de la vivienda) y se comprueba que el método de valoración contingente proporciona información fiable para realizar el análisis de políticas públicas. Finalmente, en cuanto a los modelos econométricos, se presentan resultados que indican que el logístico ordinal se ajusta mejor al formato de pregunta empleado y proporciona estimaciones consistentes de la disposición a pagar.

Concentrated Solar Power (CSP) technologies are gaining increasing interest in electricity generation due to the good potential for scaling up renewable energy at the utility level. Parabolic trough solar collector (PTC) is economically the most proven and advanced of the various CSP technologies. The modelling of these devices is a key aspect in the improvement of their design and performances which can represent a considerable increase of the overall efficiency of solar power plants. In the subject of modelling and improving the performances of PTCs and their heat collector elements (HCEs), the thermal, optical and aerodynamic study of the fluid flow and heat transfer is a powerful tool for optimising the solar field output and increase the solar plant performance. This thesis is focused on the implementation of a general methodology able to simulate the thermal, optical and aerodynamic behaviour of PTCs. The methodology followed for the thermal modelling of a PTC, taking into account the realistic non-uniform solar heat flux in the azimuthal direction is presented. Although ab initio, the finite volume method (FVM) for solving the radiative transfer equation was considered, it has been later discarded among other reasons due to its high computational cost and the unsuitability of the method for treating the finite angular size of the Sun. To overcome these issues, a new optical model has been proposed. The new model, which is based on both the FVMand ray tracing techniques, uses a numerical-geometrical approach for considering the optic cone. The effect of different factors, such as: incident angle, geometric concentration and rim angle, on the solar heat flux distribution is addressed. The accuracy of the new model is verified and better results than the Monte Carlo Ray Tracing (MCRT) model for the conditions under study are shown. Furthermore, the thermal behaviour of the PTC taking into account the nonuniform distribution of solar flux in the azimuthal direction is analysed. A general performance model based on an energy balance about the HCE is developed. Heat losses and thermal performances are determined and validated with Sandia Laboratories tests. The similarity between the temperature profile of both absorber and glass envelope and the solar flux distribution is also shown. In addition, the convection heat losses to the ambient and the effect of wind flow on the aerodynamic forces acting on the PTC structure are considered. To do this, detailed numerical simulations based on Large Eddy simulations (LES) are carried out. Simulations are performed at two Reynolds numbers of ReW1 = 3.6 × 105 and ReW2 = 1 × 106. These values corresponds to working conditions similar to those encountered in solar power plants for an Eurotrough PTC. The study has also considered different pitch angles mimicking the actual conditions of the PTC tracking mechanism along the day. Aerodynamic loads, i.e. drag and lift coefficients, are calculated and validatedwith measurements performed in wind tunnels. The indepen-dence of the aerodynamic coefficients with Reynolds numbers in the studied range is shown. Regarding the convection heat transfer taking place around the receiver, averaged local Nusselt number for the different pitch angles and Reynolds numbers have been computed and the influence of the parabola in the heat losses has been analysed. Last but not the least, the detailed analysis of the unsteady forces acting on the PTC structure has been conducted by means of the power spectra of several probes. The analysis has led to detect an increase of instabilities when moving the PTC to intermediate pitch angles. At these positions, the shear-layers formed at the sharp corners of the parabola interact shedding vortices with a high level of coherence. The coherent turbulence produces vibrations and stresses on the PTC structure which increase with the Reynolds number and eventually, might lead to structural failure under certain conditions.

Gemlik County is located in the Marmara Region (NW Turkey), which has been affected by destructive earthquakes sourced from North Anatolian Fault System throughout its history. The bulk of the settlement rests on alluvial deposits of the Gemlik pull-apart basin. So, it is vital to investigate the foundation soils in this basin and the response of them to earthquakes. Many earthquake codes were established by the authorities in different countries of the world to estimate the possible ground shaking and seismic loads which may act on buildings. In this study, Turkish Earthquake Code (TEC-1998) and Eurocode-8 (EN-1998) have been utilized. The analyses showed that EN-1998 results in more conservative estimates relative to TEC-1998, in terms of spectral ordinates. The source of difference between TEC-1998 and EN-1998 has been investigated and three possible reasons have been identified. The variation is probably due to the different seismic characteristics of Turkey and Europe, different soil amplification levels defined by the codes, and different soil classification procedures of the codes.

La feina feta en aquest treball de tesis s'ha desenvolupat a partir de tres objectius vertebradors, que fonamentalment són:·El primer dels objectius d'aquest treball de tesis és presentar un recull dels factors que intervenen en l'acústica urbanística: soroll produït pels diferents vehicles, fórmules de predicció de soroll, geometria dels edificis... , tot estudiant els seus efectes en la ciutat de Girona.·Un altre objectiu ha estat desenvolupar uns mètodes numèrics propis, contrastats experimentalment i extrapolables a qualsevol entorn urbanístic, que permetin predir els valors de les pertorbacions acústiques produïdes pels diferents vehicles en diferents situacions, entre els que es destaquen: -Fórmula de predicció del soroll en un entorn urbà i la seva aplicació a Girona.-Càlcul de l'increment de soroll en un carrer provocat per les reflexions de les ones sonores en les façanes dels edificis.-Estudi del nivell de soroll en la boca de la cavitat d'un túnel produït pel pas del ferrocarril.-Determinació del soroll provocat pel pas d'un tren sobre un viaducte.-Mètode de distribució i planificació del trànsit urbà per disminuir l'impacte acústic sobre la zona.·El darrer objectiu consisteix en fer una descripció analítica de les principals fonts de soroll que afecten a la ciutat: el trànsit viari i el ferrocarril.Per realitzar aquests objectius s'ha disposat d'un banc de dades amb més de 2.000 mesures sonores de Girona (nivells equivalents de 10 minuts de durada). La metodologia seguida i els principis en que es fonamenta es detallen a l'inici de cada apartat. La finalitat de tots aquests estudis, no és altre que millorar el confort acústic, i la qualitat de vida, de les ciutats. Gairebé tots els grans nuclis de població del planeta es veuen afectats per una gravíssima problemàtica mediambiental, doncs a l'anomenada contaminació acústica cal afegir uns alts índexs de pol·lució atmosfèrica (altes concentracions de biòxid de carboni, generació d'illes de calor...). Aquesta situació, generalitzada arreu del planeta, ha propiciat l'aparició de mesures dràstiques consistents fonamentalment en restringir l'accés dels vehicles motoritzats als nuclis i zones centrals de les àrees urbanes. Precisament aquesta opció s'ha proposat per les zones interiors de Girona on l'elevada densitat de les edificacions deixa un escàs marge per plantejar la construcció de noves rutes o vies alternatives.Cal esmentar que tots els càlculs i teories que es desenvolupen en aquest treball de tesis reflecteixen la realitat acústica actual provocada pels diferents mitjans de transport. Molt possiblement, en un futur no massa llunyà, els nivells de soroll (dB) enregistrats en situacions de tràfic similar seran força menors. Són molts els factors que poden contribuir a aquesta disminució de la intensitat de les emissions sonores: reducció del fregament mecànic, augment del coeficient aerodinàmic, nous materials pels pneumàtics i l'asfalt ... Sense cap mena de dubte, però, una millora transcendental, i no només pel que fa al confort acústic sinó per l'ecosistema en general, seria potenciar la construcció de motors elèctrics o d'hidrogen. Aquests últims per exemple, a diferència dels motors de combustió, funcionen mitjançant piles de combustible que converteixen, amb molta netedat, el gas hidrogen en electricitat i possibiliten l'existència de vehicles no contaminants propulsats per motors elèctrics menys sorollosos. Així, al haver-hi menys fregament entre les parts mòbils del motor (no hi ha pistons ni cilindres) el soroll generat es reduiria considerablement. / This thesis has been made considering three main objectives:The first one is to explain the main factors involved in noise generation and prediction: traffic and railway noise, noise prediction models, buildings geometry... This study has been applied to the city of Girona.The second objective has been develope our own numerical methods, experimentally contrasted and applicable to any urban area, to predict the noise level produced by the vehicles in different situations.The last objective consist in analize the main noise sources in the city, especially traffic and railway noise.To achieve this objectives a large data bank with approximately 2000 noise measures (equivalent sound levels) has been used. The aim of this work is to improve the quality of life, reducing the sound pressure levels.Almost all the big cities are affected by serious acoustical problems. To the so called "acoustic contamination" there are other, direct or indirectly, related environmental problems like atmospheric pollution levels. This situation is common around the planet and has propitiated the application of several restriction measures applied to traffic flow in certain urban areas. This solution has been proposed and studied from different points of view in the city of Girona.

Esta tesis propone un juego de algoritmos que puede emplearse para computar estimaciones de las distintas facetas de complejidad que ofrecen señales musicales auditivas. Están enfocados en los aspectos de acústica, ritmo, timbre y tonalidad. Así pues, la complejidad musical se entiende aquí en el nivel más basto del común acuerdo entre oyentes humanos. El objetivo es obtener juicios de complejidad mediante computación automática que resulten similares al punto de vista de un oyente ingenuo. La motivación de la presente investigación es la de mejorar la interacción humana con colecciones de música digital. Según se discute en la tesis,hay toda una serie de tareas a considerar, como la visualización de una colección, la generación de listas de reproducción o la recomendación automática de música. A través de las estimaciones de complejidad musical provistas por los algoritmos descritos, podemos obtener acceso a un nivel de descripción semántica de la música que ofrecerá novedosas e interesantes soluciones para estas tareas. / This thesis proposes a set of algorithms that can be used to compute estimates of music complexity facets from musical audio signals. They focus on aspects of acoustics, rhythm, timbre, and tonality. Music complexity is thereby considered on the coarse level of common agreement among human listeners. The target is to obtain complexity judgments through automatic computation that resemble a naive listener's point of view. The motivation for the presented research lies in the enhancement of human interaction with digital music collections. As we will discuss, there is a variety of tasks to be considered, such as collection visualization, play-list generation, or the automatic recommendation of music. Through the music complexity estimates provided by the described algorithms we can obtain access to a level of semantic music description, which allows for novel and interesting solutions of these tasks.

Établir une théorie de gravité quantique qui décrit de manière cohérente les propriétés quantiques de la matière et de l'espace-temps est l'un des défis majeurs de la physique théorique. Malgré plusieurs décennies de recherches, de nombreux problèmes conceptuels et techniques doivent encore être résolus. L'étude de modèles simplifiés donne des idées de résolution. La première partie de la thèse traite de la gravité quantique bidimensionnelle. À deux dimensions, la gravité quantique est beaucoup mieux comprise et de nombreux calculs peuvent être faits exactement. Si la gravité quantique bidimensionnelle a été largement étudiée quand elle est couplée à de la matière conforme, le cas de la matière non-conforme était très peu connu jusque récemment. Nous calculons d'abord l'action gravitationnelle pour un champ scalaire massif sur une surface de Riemann avec bords puis pour un fermion de Majorana massif sur une variété compacte. Ce dernier cas correspond à une CFT perturbée par une perturbation conforme et est d'ordinaire étudié grâce à l'ansatz de DDK, mais les résultats sont différents. Finalement, on calcule le spectre de l'action de Mabuchi dans l'approximation du minisuperespace. La seconde partie étudie les propriétés thermales des trous noirs dans le contexte de la correspondance AdS/CFT. On construit un modèle de mécanique quantique fondé sur les principes holographiques pour simuler la dynamique des trous noirs quantiques. Ce modèle permet d'obtenir des résultats numériques exacts. / Finding a theory of quantum gravity describing in a consistent way the quantum properties of matter and spacetime geometry is one of the greatest challenges of modern theoretical physics. However after several decades of research, many conceptual and technical issues are still to be resolved. Insights on these questions can be given by simplified toy models that allow for exact computations. The first part of the thesis deals with two-dimensional quantum gravity. In two dimensions quantum gravity is much better understood and many computations can be carried out exactly. Whereas two-dimensional quantum gravity coupled to conformal matter has been widely studied and is now well understood, much less was known until recently when matter is non-conformal. First we compute the gravitational action for a massive scalar field on a Riemann surface with boundaries and then for a massive Majorana fermion on a manifold without boundary. The latter case corresponds to a CFT perturbed by a conformal perturbation and is usually tackled through the DDK ansatz, but the results do not seem to match. Finally we give a minisuperspace computation of the spectrum of the Mabuchi action, a functional that appears in the gravitational action for a massive scalar field. In the second part we focus on black hole thermal behaviour which provides a lot of insight of how a theory of quantum gravity should look like. In the context of string theory the AdS/CFT correspondence provides powerful tools for understanding the microscopic origin of black holes thermodynamics. We construct a quantum mechanical toy model based on holographic principles to study the dynamics of quantum black holes.

Ce travail était centré sur les propriétés thermodynamiques et mécaniques des polymères denses et sur leurs liens avec les systèmes de la matière molle et l'étude des propriétés de conformation et les propriétés rhéologiques des polymères hyperbranchés. L'étude de polymères hyperbranchés montre qu'ils sont substantiellement différents de leurs analogues linéaires. En utilisant des méthodes de simulation, nous pouvons obtenir des informations inaccessibles par des méthodes expérimentales et heureusement obtenir de précieuses informations du point de vue industriel et scientifique. Cette étude traite le problème par des simulations et comme expliqué dans le manuscrit, nous avons observé un centre de faible densité pour un grand nombre de générations et une enveloppe extérieure plutôt compacte. Cette tendance se retrouve également pour les propriétés dynamiques. Le manque d’enchevêtrement dans les polymères hyperbranchés fait d'eux des matériaux moins résistant que ceux composés de chaînes linéraires. La viscosité perd sa simple dépendance à la masse dans le cas d'une chaîne linéaire. / This study is focused on thermodynamic and mechanical properties of dense polymers solutions and related soft matter systems and conformational and rheological properties of hyperbranched polymers. Studies of hyperbranched polymers shows that they are substantially different from their linear analogs. By using simulation methods we could reach the information not available by experimental methods and hopefully obtain valuable information from both industrial and scientific points of view.This study is treating this problem by means of computer simulations where as a result we can see a hollow center for high generation numbers and a rather compact outer shell. This tendency expands to dynamical behavior. Lack of chain entanglements in hyperbranched polymers make them not very tough materials in a comparison with linear chains. Another point is a decrease of mobility caused by large amount of branch points. Viscosity loses its simple dependence on the mass as for the case of linear chains.