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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.
11

Inner structure and atmospheric dynamics of gaseous giant planets / Structure interne et dynamique atmosphérique des planètes géantes gazeuses

Debras, Florian 21 December 2018 (has links)
Lors de cette thèse, je me suis attaché à améliorer notre connaissance des planètes géantes, depuis notre voisine Jupiter jusqu’aux exoplanètes lointaines : les Jupiter chauds. Grâce aux nouvelles observations gravitationnelles extrêmement fines du satellite Juno, entré en orbite autour de Jupiter en juillet 2016, il est possible d’améliorer significativement les modèles de structure interne de la planète. Cependant, cela ne peut se faire qu’à condition d’avoir une méthode suffisamment précise pour exploiter au maximum les données. J’ai donc étudié la méthode des sphéroides de Maclaurin concentriques et ses limitations. A l’aide des connaissances contemporaines sur les équations d’état, les propriétés diffusives et les transition ou séparation de phase entre l’Hydrogène et l’Hélium, il m’a alors été possible de produire de nouveaux modèles de Jupiter. Arriver à combiner les observations gravitationnelles de Juno et les abondances d’éléments observées par Galiléo n’a pu se faire qu’en décomposant Jupiter en au moins 4 zones, de l’enveloppe externe jusqu’au coeur compact. J’ai montré que la taille de ce coeur compact était dégénérée avec la variation d’entropie à l’intérieur de la planète.La structure interne des Jupiter chauds quant à elle est très dépendante de leur dynamique atmosphérique, qui entraîne une inflation de leur rayon. J’ai étudié les atmosphères de ces planètes à l’aide du modèle de circulation globale de l’Université d’Exeter et d’un code linéaire que j’ai développé, appelé ECLIPS3D. La caractéristique la plus importante de la circulation atmosphérique est la présence d’un jet superrotatif, étendu en latitude.J’ai donc étudié la création de ce jet à l’aide d’arguments théoriques pour s’assurer de sa pertinence physique. L’étude de la solution linéaire dépendante du temps, associée à des arguments numériques sur la convergence de quantité de mouvement par les vents verticaux m’ont permis d’établir une compréhension globale, cohérente de l’accélération de la superrotation dans l’atmosphère de ces planètes.Avec ce travail, j’ai amélioré ma compréhension théorique des planètes géantes et développé des codes qui peuvent être utilisés pour améliorer nos connaissances sur la structure interne et la dynamique atmosphérique des planètes géantes, que ce soit Jupiter, Saturne ou les Jupiter chauds. / Through this thesis, I have been motivated by the will to improve our knowledge of giant planets, from our neigh- bouring Jupiter to the far away worlds across the galaxy: hot Jupiters.With the latest, extremely precise observations of the satellite Juno, new models of the interior of Jupiter can be derived. A precise enough method is required to take full advantage of these outstanding data, and I therefore studied the concentric Maclaurin spheroid method and its limitations.With contemporary understanding on the equations of state, diffusive properties and phase transition/separation of hydrogen and helium, I could then focus on producing new interior models of Jupiter. Combining the gravitational observations of Juno with the elemental observations of Galileo has proven to be a complicated task, which required to decompose the planet into at least four regions from the outer envelope to the inner, compact core. I have shown that the size of the compact core is degenerated with the entropy variation within the planet.Concerning hot Jupiters, I have reminded of the need to understand their atmospheric dynamics to constrain their interior structure, as the wind circulation can lead to an inflation of their radius. Studying numerically their at- mospheric dynamics was performed with the University of Exeter’s global circulation model as well as with the development of a linear solver that I called ECLIPS3D. An important, robust feature is the presence of a broad equatorial superrotation in the atmosphere of these planets.Finally, I have explored the spin up of this superrotation on theoretical grounds, to assess its physical relevance. I have calculated the linear time dependent solution to show the importance of differential drag and radiative damp- ing, and have used numerical simulations to highlight the importance of vertical momentum acceleration. Globally, a coherent picture of the initial spin up of superrotation was obtained.Through this work, I have improved my theoretical understanding of giant planets and developed various codes that can be used to study and improve our knowledge of the interior structure and atmospheric dynamics of giant planets, from Jupiter and Saturn to hot Jupiters.
12

Kriminologické aspekty organizované kriminality / Criminological aspects of organized crime

Kovářová, Alena January 2019 (has links)
7 Criminological aspects of organized crime Abstract The aim of this study named Criminological aspects of organized crime is mainly to provide a general insight to organized criminality as itself a systematize particular legal and social means, that are used to fight organized crime these days. Apart from the identification of the problems connected with application of certain means in practice I tried to outline possible solutions for the future that would lead to increasing the effectivity of fight with organized crime. The first chapter is focused on the general definition of organized crime and particular trait names that characterise organized crime and distinguish it from other forms of criminal activity. The second chapter called development of organized crime is dedicated mainly to historical roots of organized crime, its origin and changes through time. The most important global organized criminal groups are described in the second part of this chapter, which are an Italian Mafia, American La Cosa Nostra, Chinese triad and other. The third chapter focuses on typology of organized crime and particular internal organizational structure, their typical signs an expressions, whereas offers several means of division. In the fourth chapter, I devoted myself to the development of organized crime in the...
13

IMPROVING MIX DESIGN AND CONSTRUCTION OF PERMEABLE FRICTION COURSE MIXTURES

Alvarez Lugo, Allex Eduardo 2009 December 1900 (has links)
Permeable friction course (PFC), or new generation open-graded friction course (OGFC) mixtures, are hot mix asphalt (HMA) characterized by high total air voids (AV) content (minimum 18 %) as compared to the most commonly used dense-graded HMA. The high AV content confers to PFC mixtures both high permeability and noise reduction effectiveness. These characteristics and the high values of surface friction exhibited by PFC mixtures, as compared to dense-graded HMA, lead to improvements in safety and the environment, which make PFC one of the safest, cleanest, and quietest alternatives currently available for surface paving. The main objective of this study was improving the current PFC mix design method and construction practices in terms of compaction control. Corresponding results were integrated in an improved mix design method that is based on the guidelines of the current mix design method used by the Texas Department of Transportation. The improved mix design included modified computation of the inputs required to determine mixture density (or corresponding total AV content). These changes led to a proposed modification of the density specification for mix design from 78-82 % to 76-80 %. In addition, the water-accessible AV content was proposed as a surrogate of the total AV content for mix design and evaluation. The improved mix design method also includes verification of drainability, durability, and stone-on-stone contact. Computation of the expected value of permeability (E[k]) and measurement of the water flow value were recommended, respectively, for verification of drainability in the laboratory (using specimens compacted in the Superpave Gyratory Compactor (SGC)) and in the field. The Cantabro loss test conducted in both dry- and wet-conditions was suggested for assessing mixture durability. Improved criteria were proposed for verification of stone-on-stone contact based on the evaluation of the AV content in the coarse aggregate fraction of the mixture. In addition, comparison of the internal structure of field-and laboratory-compacted mixtures supported recommendation of a field-compaction control. Recommendations to reduce the horizontal heterogeneity of AV encountered in PFC specimens included using road cores with a minimum 152.4 mm diameter and coring SGC specimens from 152.4 to 101.6 mm in diameter
14

Le réseau social des gangs montréalais : accès aux dynamiques relationnelles par l'entrevue de groupe

Descormiers, Karine January 2008 (has links)
Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal
15

Probing the proton structure through deep virtual Compton scattering at COMPASS, CERN / Etude de la structure interne du proton par diffusion Compton virtuelle à COMPASS, CERN

Vidon, Antoine 01 October 2019 (has links)
La diffusion Compton virtuelle (DVCS) est un processus idéal pour étudier la structure interne du proton. Cette réaction exclusive permet d’accéder aux distributions de partons généralisées (GPDs) qui encodent les corrélations entre impulsion longitudinale et position transverse des partons à l’intérieur du proton. Le DVCS consiste à sonder le proton au moyen d’un photon virtuel de grande virtualité pour produire dans l’état final un unique photon réel de grande énergie tout en laissant le proton intact.A COMPASS au CERN, où deux années de données ont été collectées en 2016 et 2017 afin de mesurer la section efficace du processus DVCS, le photon virtuel est issu de la diffusion d’un faisceau de μ⁺ ou de μ⁻ polarisé de 160 GeV sur une cible d’hydrogène liquide. Toutes les particules de la réaction sont détectées dans l’expérience : le muon incident est détecté dans le télescope du faisceau, le muon diffracté et le photon réel sont détectés à l’avant dans le spectromètre et les trois calorimètres tandis que le proton de recul est détecté dans un détecteur de temps de vol placé autour de la cible.Je présente dans cette thèse l’état de l’analyse du processus DVCS sur les données collectées à COMPASS en 2016. Après un rappel du contexte théorique et expérimental, je décris l’expérience COMPASS. Je détaille ensuite mon travail de calibration du détecteur de proton de recul et de détermination de la position exacte de la cible de 2 cm de diamètre et 2.5 m de longueur. J’étudie dans la partie suivante la sélection de différents canaux de physique permettant de contrôler de manière systématique la qualité des détecteurs : la diffusion profondément inélastique (DIS) qui implique le télescope du faisceau et le spectromètre, la production exclusive de ρ⁰ qui inclut aussi le détecteur de temps de vol ; puis je présente la première analyse de la production exclusive de photons uniques qui implique en plus les trois calorimètres. Dans une dernière partie j’évoque les étapes nécessaires à la détermination de la section efficace du DVCS à partir de cette sélection, et je présente les premiers résultats issus de la simulation associée. / Virtual Compton Scattering (DVCS) is an ideal process to study the internal structure of proton. This exclusive reaction provides access to generalised parton distributions (GPDs), which encode the correlations between longitudinal momentum and transverse position of partons inside the proton. DVCS consists in probing a proton with a virtual photon of high virtuality, in order to produce a single high energy real photon while leaving the proton intact in the final state.At COMPASS at CERN, where two years of data were collected in 2016 and 2017 to measure the DVCS cross section, the virtual photon is produced by scattering of a 160 GeV polarised μ⁺ or μ⁻ beam on a liquid hydrogen target. All particles are detected in the experiment: the incident muon is detected in the beam telescope, the diffracted muon and the real photon are detected in the forward spectrometer and the three calorimeters, while the recoil proton is detected in a time-of-flight detector positioned around the target.In this thesis I present the state of the analysis of the DVCS process on the data collected at COMPASS in 2016. After a reminder of the theoretical and experimental context, I describe the COMPASS experiment. I then detail my work on calibrating the recoil proton detector and determining the the exact position of the 2 cm diameter and 2.5 m long target. In the next section, I study the selection of different physics channels used to systematically control detector quality: Deep Inelastic Scattering (DIS) which involves the beam-telescope and spectrometer, exclusive ρ⁰ production which requires the addition of the time-of-flight detector and I follow with the first analysis of the exclusive single photon production which depends as well on the calorimetres quality. In a last part, I discuss the necessary steps needed to extract the DVCS cross-section out of this event selection, and present the first results associated to the Monte-Carlo simulation.
16

Fault zones in potential geothermal reservoir rocks in the Upper Rhine Graben: Characteristics, permeability implications, and numerical stress field models

Meier, Silke 03 May 2016 (has links)
Störungszonen in den karbonatischen Wechselfolgen des Muschelkalks (Mittlere Trias) sind potenzielle Ziele für hydrothermale Projekte im Oberrheingraben (ORG). Es wurden verschiedene Methoden miteinander kombiniert, um die Permeabilitäts-Strukturen solcher Störungszonen, deren Spannungszustände und lokale Spannungsfelder abzuschätzen. Diese Arbeit kann damit zur Exploration von störungsgebundenen Muschelkalk-Reservoiren im ORG beitragen. Sie vergleicht diese mit einem bereits erfolgreich getesteten (störungsgebundenen) hydrothermalen Reservoir, den Sandsteinen des Buntsandsteins. Um für den Muschelkalk die Charakteristika von Störungszonen zu definieren und die zugehörige Permeabilitätsstruktur abzuschätzen, wurden verschiedene Störungszonentypen (z.B. Abschiebungen, invertierte Störungszonen, Schrägabschiebung) mit unterschiedlichen Maßstäben (Versatz: mittel-skalig 1-10 m, groß-skalig >10 m) detailliert untersucht. Eine Aufschlussanalogstudie zu einer groß-skaligen Störungszone (Schrägabschiebung) in dickbankigen Sandsteinen (Buntsandstein, Untere Trias) wurde zum Vergleich herangezogen. Der besondere Schwerpunkt lag jeweils auf der Charakterisierung von Bruchzone und Störungskern sowie des assoziierten Bruchsystems (Bruchdichte, Öffnungsweitenverteilung, Vernetzungsgrad, vertikale Ausdehnung). Die Daten zeigen, dass Bruchsysteme in eher homogenen Einheiten einen positiven Effekt auf die Reservoir-Permeabilität haben. Sie bieten, vor allem in der Nähe des Störungskerns, potenzielle Fließwege auch über mehrere Schichten und zeigen eine starke Vernetzung zwischen vergleichsweise kurzen Brüchen. Im Gegensatz dazu scheinen störungsgebundene Bruchsysteme in Einheiten mit einer starken mechanischen Schichtung einen geringeren Einfluss auf die Reservoirpermeabilität zu haben. Störungskerne zeigen stellenweise eine signifikante Komplexität, da sie vor allem abdichtende aber stellenweise auch durchlässige Strukturen aufweisen. Groß-skalige Störungszonen (im Reservoir-Maßstab) lassen sich für beide potenzielle Reservoirhorizonte am besten als kombinierte Barriere-Leiter-Systeme beschreiben. Diese Barriere-Leiter-Systeme zeichnen sich durch ein potenziell hydraulisch durchlässiges Bruchsystem in der Bruchzone (und im Buntsandstein zusätzlich in der Übergangszone) sowie einen schwach durchlässigen bis abdichtenden Störungskern aus. Um die Kenntnisse zum lokalen Spannungsfeld in Störungszonen im geschichteten Muschelkalk (Reservoirtiefe: 2.900 m) zu verbessern, wurden mit der Finite-Elemente-Software COMSOL Multiphysics® numerische 3D-Modelle erstellt. Es wurden deutliche Unterschiede des lokalen Spannungsfelds in Abhängigkeit von (1) der Orientierung, (2) dem Einfluss der maximalen Horizontalspannung SH im Spannungsregime, (3) Störungszonen-Maßstab und (4) den Kontrasten der mechanischen Eigenschaften festgestellt. In Spannungsregimen mit starker horizontaler Kompression wurde für Spannungsmagnituden und Versatz eine deutliche Abhängigkeit von der Orientierung der Störungszone festgestellt. Vor allem groß-skalige Störungszonen mit einem 30°-Winkel zu SH scheinen einen SH-induzierten Horizontalversatz innerhalb weicher Störungszoneneinheiten zu begünstigen; in dieser wurden die höchsten Versatzbeträge festgestellt. Die typische Abnahme von Spannungsmagnituden in weicheren Störungszoneneinheiten verringert sich in Richtung von Störungszonen, die senkrecht zu SH streichen. Der Einfluss der mechanischen Schichtung steigt mit zunehmender horizontaler Kompression, was zu einem vertikal heterogenen Spannungsfeld führt. Um Annahmen zu einer möglichen hydraulischen Aktivität einer Störungszone zu treffen, werden für die untersuchten Störungszonen analytische Abschätzungen zu Bewegungs- und Dehnungstendenzen unter Reservoir-Bedingungen präsentiert. Die Ergebnisse zeigen unterschiedliche Spannungszustände der analysierten Störungszonen, die auf das rezente Übergangsregime sowie unterschiedliche Orientierungen der maximalen Horizontalspannungen SH zurückzuführen sind. In dieser Arbeit präsentierte Ergebnisse von Aufschlussanalogstudien helfen dabei, fundierte Annahmen zur Permeabilitätsstruktur von Störungszonen zu treffen und damit vielversprechende Bohrziele im ORG zu definieren. In diesem Zusammenhang konnten sedimentäre Wechselfolgen identifiziert werden, die als potenzielle geothermische Reservoire ausgeschlossen werden können. Die Ergebnisse der numerischen 3D-Modellierungen können dazu beitragen, möglicherweise nötige Stimulationsmaßnahmen im Muschelkalk Reservoir optimal auszulegen. Darüber hinaus bieten die Ergebnisse die Möglichkeit, Einblick in potenzielle Probleme während der Bohrungsherstellung in Muschelkalk-Reservoiren zu bekommen, wie zum Beispiel die Wahrscheinlichkeit eines vertikal heterogenen Spannungsfeldes.
17

Polovětné gerundiální a ing-ové participiální vazby v psaném a mluveném odborném textu / Gerundial and ing-participial clauses in written and spoken academic texts

Pajmová, Klára January 2013 (has links)
This Master's thesis deals with the gerund and -ing participial clauses in written and spoken academic texts. The theoretical part defines the academic discourse and non-finite verb forms. Gerund and -ing participial constructions are further described regarding their forms and syntactic functions. The sources used for the research part are two corpora of contemporary academic British English: BASE and BAWE. BASE corpus contains transcripts of academic lectures. BAWE corpus is a collection of university-level students' writings. Both corpora contain texts from four different genres and moreover students' assignments are divided into four levels of study. For the purpose of the research part of our thesis, only the genre "Arts and Humanities" and the highest level of study will be taken into account. The practical part analyses the frequency of gerund and -ing participial clauses, frequency of verbs occurring in these constructions and collocations of these verbs. A detailed analysis aims at studying 100 sentences from written texts and 100 sentences from academic lectures. This sample is examined regarding the internal structure of each non-finite clause and its syntactic function. The final section summarizes the results or our research.
18

Návrh trupu letounu TL-4000 / Fuselage design of TL-4000 aircraft

Holiš, Michal January 2014 (has links)
Táto diplomová práca sa zaoberá návrhom kompozitového trupu štvormiestneho jednomotorového turistického letúnu TL-4000, ktorý spadá do kategórie CS-23 zo zameraním sa na zadnú časť. V tejto práci je vypracovaný návrh vnútornej konštrukcie s ohľadom na posádku a pasažierov. Z navrhnutej konštrukcie je vytvorený MKP model po ktorom nasleduje vypracovanie a vyhodnotenie skladby laminátových a sendvičových častí nosnej konštrukcie pomocou softvérov MSC.Patran/Nastran a ComPost pre vypočítané kombinácie vzdušného zaťaženia.
19

Forças regionais, formas urbanas e estrutura interna da cidade : um estudo de relações

Colusso, Izabele January 2015 (has links)
A busca pelo entendimento das transformações espaciais que são geradas diante do aumento do número de pessoas que vivem em cidades, do consequente aumento do espaço urbanizado, dos impactos na questão de consumo de espaço, e assim, das novas formas urbanas é assunto perseguido por diversas pesquisas. Nesta investigação, discutese a possibilidade de influência que o sistema regional pode ter sobre as formas urbanas que as cidades tendem a assumir. A diferença de escala envolvida nesta visão, que vai desde a escala regional, passa pela escala municipal, e chega à escala intraurbana, traz uma nova ótica no entendimento do paradoxo da estocástica dos modelos: que contradigam evidências empíricas porque sugerem que as cidades podem se desenvolver de forma independente. Colocada esta conjuntura que apresenta a maneira como hoje se aborda forma urbana, cidade e região, verifica-se que os estudos carecem de uma maior conexão e avaliação das influências entre as diferentes escalas e impactos. O encaminhamento desta pesquisa se dá através da proposta de um roteiro metodológico que envolve a medida de tensão regional, e verificações estatísticas e espaciais. Para esta verificação, foi utilizado o caso da região central do estado do Rio Grande do Sul, um sistema regional composto por 27 cidades, em 3 períodos de tempo, tornando possível a comparação das formas urbanas e seu respectivo crescimento e influência na estrutura interna das cidades. Os instrumentos desenvolvidos para obtenção de resultados nesta investigação fornecem uma ferramenta útil para estudar a influência do efeitos espaciais sobre a agregação de modelos de interação espacial e o quanto podem contribuir de diversas maneiras para realizações substanciais em estudos econométricos espaciais, além de que sugerem ferramentas estatísticas que inferem o valor, intensidade e hierarquia provável de fluxos médios a certos níveis de agregação de variáveis disponíveis reais e estimadas. As possibilidades de visualização e comparação da repercussão entre diferentes escalas espaciais permite assim relacionar escalas regionais, municipais e intraurbanas, e constata-se que existe grande influência da escala regional sobre as alterações da estrutura interna da cidade. / The search for understanding the spatial transformations that are generated by the increase in the number of people living in cities, the resulting increase in urbanized space, impacts on the issue of space consumption, and thus, new urban forms, is a subject pursued by several researches. In this investigation, we discuss the possible influence that the regional system can have on urban forms that cities tend to assume. The difference of scale involved in this vision, ranging from regional, passes through the municipal scale, and comes to the intraurban scale, brings a new light on the paradox of understanding the stochastic models: that they contradict empirical evidence, because they suggest that cities can develop independently from each other and from the region where they are inserted. Placed this scenario that shows how today are addressed urban form, cities and regions, it appears that is required further studies and evaluation of connection between the different scales influences and impacts. The forwarding of this research is through the proposal of a methodological plan that involves regional tension measurement, and statistics and spatial verification. To check this, we used the case of the central region of the state of Rio Grande do Sul, a regional system composed by 27 cities in three periods of time, making it possible to compare the urban forms and their respective growth and influence in the internal structure of the cities. The instruments developed to achieve results in this study provide a useful tool for studying the influence of spatial effects on the aggregation of spatial interaction models and how much they can contribute in several ways to substantial achievements in spatial econometric studies, and suggest that statistical tools to infer the value, intensity and probable hierarchy of average flows at certain levels of aggregation of real variables available and estimated. The display options and comparison of the impact of different spatial scales makes it possible to relate regional, municipal and intra-urban scale, and it appears that there is a great influence on regional scale changes in the internal structure of the city.
20

Structure interne et propriétés thermiques macroscopiques, application aux matériaux de construction / Internal structure and macroscopic thermal properties, application to construction materials

Faye, Mactar 26 May 2016 (has links)
L'objectif de cette thèse est d'étudier l'impact de la structure interne des matériaux isotropes granulaires sur leurs propriétés thermiques macroscopiques. Nous avons développé un code de calcul pour résoudre les transferts thermiques au sein d'un matériau hétérogène tridimensionnel. Ce code est couplé avec un algorithme de génération de structures aléatoires. Après validation expérimentale, nous avons généré des géométries granulaires dont nous avons caractérisé la structure interne, puis nous avons étudié l'impact de cette structure sur la conductivité thermique. Nous avons également développé une nouvelle méthode de mesure expérimentale de la capacité thermique surfacique d'un élément de paroi à structure interne complexe. L'originalité de cette méthode est le couplage d'un modèle analytique de la capacité thermique, indépendant des propriétés thermiques des constituants, et d'une étude expérimentale. / The objective of this thesis is to study the impact of the internal structure of isotropic granular materials on the macroscopic thermal properties. We have developed a model to solve the heat transfer problem within a heterogeneous three-dimensional material. This code is coupled with an algorithm generating random structure. After an experimental validation, we first generated granular materials and we characterized their internal structure; then we studied the impact of this structure on the thermal conductivity. We also developed a new experimental method for measuring the heat capacity area of a wall element with complex internal structure. The originality of this method is the coupling of an analytical model of heat capacity area, which is independent of the thermal properties of the constituents, and an experimental study.

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