Thèses : « External limit »

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NYS, MANON. « Schrödinger equations with an external magnetic field : spectral problems & ; semiclassical states ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2015. http://hdl.handle.net/10281/89252.

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In this thesis, we study Schrödinger equations with an external magnetic field. In the first part, we are interested in an eigenvalue problem. We work in an open, bounded and simply connected domain in dimension two. We consider a magnetic potential singular at one point in the domain, and related to the magnetic field being a multiple of a Dirac delta. Those two objects are related to the Bohm-Aharonov effect, in which a charged particle is influenced by the presence of the magnetic potential although it remains in a region where the magnetic field is zero. We consider the Schrödinger magnetic operator appearing in the Schrödinger equation in presence of an external magnetic field. We want to study the spectrum of this operator, and more particularly how it varies when the singular point moves in the domain. We prove some results of continuity and differentiability of the eigenvalues when the singular point moves in the domain or approaches its boundary. Finally, in case of half-integer circulation of the magnetic potential, we study some asymptotic behaviour of the eigenvalues close to their critical points. In the second part, we study nonlinear Schrödinger equations in a cylindrically setting. We are interested in the semiclassical limit of the equation. We prove the existence of a semiclassical solution concentrating on a circle. Moreover, the radius of that circle is determined by the electric potential, but also by the magnetic potential. This result is totally new with respect to the ones before, in which the concentration is driven only by the electric potential.

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BRIAMONTE, ANNAMARIA. « L'eccesso di potere del giudice amministrativo ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2021. http://hdl.handle.net/10281/329940.

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L’indagine verte intorno alla figura dell’eccesso di potere del giudice amministrativo, che rappresenta uno dei motivi di giurisdizione sindacabili dinanzi alla Corte di Cassazione ai sensi dell’art. 111, comma 8, Cost. Ne viene scandagliata la matrice storica, che rinviene il suo fondamento nella legge sui conflitti del 1877, l’evoluzione normativa, l’elaborazione dogmatica nell’ambito del dibattito scientifico e della prassi giurisprudenziale sino ai più recenti sviluppi applicativi. Il fulcro dell’istituto, che si sostanzia nella fattispecie dello sconfinamento, da parte del giudice amministrativo, nelle prerogative attribuite al legislatore o all’amministrazione, viene esplorato nella sua essenza contenutistica: con riguardo al quadro dei rapporti tra giurisdizione e amministrazione, la disamina corre lungo i sentieri ermeneutici in cui si innestano i concetti di discrezionalità (anche tecnica), merito, sindacato di legittimità, sindacato di merito; rispetto all’ipotesi dell’invasione del potere legislativo - la cui analisi viene inserita in una sezione ad hoc, in considerazione delle peculiarità della figura - la riflessione ruota sostanzialmente intorno alla constatazione di un suo rilievo pressoché solamente teorico, in considerazione della ampia portata e della valenza sistemica riconosciuta (e da riconoscersi) all’interpretazione giudiziale, l’attività di creazione sic et simpliciter della norma costituendo una evenienza di difficile (se non rara) verificazione in concreto. L’invasione da parte del giudice amministrativo delle facoltà riconosciute all’amministrazione - che costituisce il campo di elezione del lavoro - viene indagata, oltre che da un punto di vista dogmatico, nella prospettiva del sindacato della Corte regolatrice della giurisdizione nelle varie declinazioni in cui la stessa è suscettibile di tradursi, nella cornice della giurisdizione generale di legittimità, di merito (con specifico riguardo al giudizio di ottemperanza) ed esclusiva del giudice amministrativo. Punto cruciale della trattazione è il tentativo di individuare una netta linea di confine tra l’eccesso di potere giurisdizionale e l’omonimo vizio inficiante l’atto amministrativo, pur nella consapevolezza di una loro matrice dogmatica comune. Una tale direzione di ricerca si rivela proficua in vista della maturazione dei risultati di un’indagine volta essenzialmente ad enucleare e valorizzare la funzione dell’eccesso di potere del giudice amministrativo nel contesto ordinamentale di riferimento, e, per tale via, il ruolo (di garanzia) della Corte di Cassazione nelle sue vesti di giudice dei conflitti.
The research is focused on the excess of power of the administrative judge, one of the reasons of jurisdiction that can be reviewed before the Court of Cassation according to Article 111, paragraph 8, of the Italian Constitution. The historical matrix, which finds its basis in the law on conflicts of 1877, its evolution across the legislation, its dogmatic elaboration within the scientific debate and its development by case law are explored, coming up to its most recent applications. The core of the figure, which corresponds to the trespassing by the court on the prerogatives belonging to the legislator or the administration, is explored in its essence. On the one hand, about the relationships between jurisdiction and administration, the analysis is structured around concepts such as discretion (also technical), merit, legitimacy review and merit review. On the other hand, with respect to the hypothesis of the encroaching on legislative power - whose analysis is included in an ad hoc section, considering the peculiarities of the hypothesis - the reflection essentially revolves around the acknowledgment of its almost purely theoretical importance, due to the broad meaning granted to the judicial interpretation of the norms which precludes the qualification of the activity of the judge as an exercise of normative creation. The trespassing by the administrative judge on the powers belonging to the administration - which constitutes the chosen field of the work - is investigated not only from a dogmatic point of view but also from the perspective of its concrete review by the Court of Cassation, in relation to all forms of the jurisdiction of the administrative judge: from the general jurisdiction of legitimacy to the merit jurisdiction (with specific regard to the judgment of compliance) and to the exclusive jurisdiction. The crucial point of the discussion is the attempt to identify a clear boundary between the excess of jurisdictional power and the homonymous flaw affecting the administrative act, being aware of their common dogmatic foundation. Such an interpretative key appears especially useful in relation to the objectives of a survey essentially aimed at identifying and enhancing the function of the excess of power of the administrative judge in the context of the Italian judicial system, and, in this way, the (guarantor) role of the Court of Cassation as judge of conflicts.

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Lund, Gustav. « Model for risk evaluation for fragment debris after a grenade detonation ». Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-84576.

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Accidents when using or storing explosives can lead to a large number of casualties and injuries. Hence, it is of vital importance, in all countries, to know the risk and act responsibly when working with explosives. A model for evaluating the risk for fragment-induced injuries from grenade detonation is created starting from experimental data of three different types of grenades. The grenades differ in shape, type of explosives and design. The experiments were conducted shooting the grenades on a wooden target and the fragments from the grenade detonation were collected by witness packages. The witness packages have a layered structure of aluminum plates and polystyrene foam. The collected fragments are weighted and the number of perforated plates for each fragment are counted. From the number of perforated plates the impact velocities of the fragments are calculated and ballistics is then used to obtain the initial velocity of the fragments. Fragmentation is regarded as a stochastic event and a distribution will more correctly describe the variation in shapes and sizes of the fragments. All data obtained in the experiment are evaluated and used to create distributions describing the fragmentation of the grenades. The fragmentized objects are accelerated by the detonation and will, under the influence of the medium, decreases their velocities. The velocity of the fragmentized objects are compared to criterions for skin perforations developed in the 20th century. According to a risk assessments manual, develop by the Swedish defense research agency (FOI), the risk of severe injury can be regarded as acceptable when it occurs one in a million detonations. The distance where only one fragment in one million detonations has the ability to perforate bare skin, according to the injury criterions, is calculated using the developed model. For the three tested grenades the distance at which the injury is acceptable (safety distance) did vary between 55 m and 240 m. The variation in safety distances is assumed to be due to design variation between the three grenades and also dependent on the model for injury criteria that was used.
Det är för alla länder viktigt att veta riskerna med de sprängmedel och ammunition som förvaras och används av deras försvarsmakter. Olyckor som kan uppstå vid förvaring och användning av dessa vapen kan leda till omfattade skador på personer i omgivningen. En modell för att beräkna riskerna för skador från fragmenterade föremål från en detonation har skapats från experiment med tre olika typer av granater. De tre granaterna varierar i form, typ av sprängmedel samt den övergripande designen. Experimenten genomfördes genom skjuta de olika granaterna mot ett mål i trä, fragmenten som skapades vid detonationen fångades sedan upp av vittnespaket. Vittnespaket har en struktur bestående av flera lager aluminiumplåtar och frigolit. Fragment som fångats av dessa paket vägs och från antalet perforerade plåtar räknas. Från antalet perforerade plåtar kan anslagshastigheten för fragmentet beräknas, ballistik används sedan för att beräkna den initiala hastigheten för fragmentet. Från den data som erhållits av experimentet skapas en fördelning av möjliga massor och en för möjliga hastigheter för fragmenten. Fördelningarna används för att beskriva problemet, då fragmentering anses vara en stokastisk process. Fragment som accelererats av detonationen kommer bromsas genom att dessa interagerar med mediet de färdas i. Hastigheten som fragmenten har vid olika distanser från detonationen jämförs med villkor för hudperforering som utvecklats under 1900-talet. Enligt en riskmatris utvecklad av Totalförsvarets forskningsinstitut FOI, anses risken för alvarlig skada vara accepterat om skadan inte uppstår oftare än en gång på en miljon fall. Avståndet där endast ett fragment per en miljon detonerade granater har en hastighet tillräckligt hög för att perforera hud beräknas av modellen. För de testade granaterna varierade detta avstånd mellan 55 och 240 m. Skillnaden i avstånd tros bero på skillnader i granaternas är designade, samt vilket villkor för hudperforering som används.

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Nelsen, Anna Carolina Haiduk. « Comportamento estrutural de vigas mistas de aço e concreto com protensão externa ». Universidade Federal de São Carlos, 2013. https://repositorio.ufscar.br/handle/ufscar/4685.

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Made available in DSpace on 2016-06-02T20:09:18Z (GMT). No. of bitstreams: 1 5306.pdf: 6510064 bytes, checksum: b7a3095b2eb1b62ba399cfe3a2684382 (MD5) Previous issue date: 2013-07-11
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This report investigates the structural behavior, procedures for analysis and design of externally prestressed steel-concrete composite beams. Based upon the requirements outlined in ABNT NRB 8800:2008 for conventional composite beams and in the literature review, a systematic procedure was developed to design of externally prestressed steel-concrete composite beams requested the positive bending moment. Was analyzed the main modes of global collapse, especially the ultimate limit state design (ELU), which may occur in this type of structure. Also, elaborated a parametric study aimed to analyze the influence of variation in the level of prestressing and the eccentricity of tendons, as well as the constructive methodology (pretensioning and posttensioning) adopted for the the prestressing steel profile that makes up the of steel-concrete composite beam. The parametric study showed that in both methods the predominant failure mode occurs in 2nd Stage of construction. In models of composite beams analyzed with application of pretensioned when the tendon is positioned above the bottom flange of the profile steel the failure mode occurred for the combined bending and axial compression .As for the composite beams evaluated with posttensioned, independent of the position of the tendon, the failure mode occurred in function of the bending moment more than the allowable flexural strength. However, it is noted that the level of prestressing can be adequately calculated to ensure that there is no loss of carrying capacity of the structure. It was also observed that regardless of the constructive methodology adopted, higher eccentricities result in higher bearing capacity for the steel beam, as exposed in the literature review. While in Brazil is largely unexplored, there was widespread interest in the international literature on the subject in question and their variances, giving rise to theoretical and experimental. Also been mentioned as potential applications in the design of new structures and the renovation and rehabilitation of existing structures.
O presente trabalho discorre sobre o comportamento estrutural, procedimentos de análise e dimensionamento de vigas mistas de aço e concreto protendidas externamente. Embasado nas prescrições expostas na norma ABNT NRB 8800:2008 para vigas mistas convencionais e na revisão bibliográfica, um procedimento de cálculo foi desenvolvido para o dimensionamento de vigas mistas de aço e concreto protendidas externamente e solicitadas a momento fletor positivo. Foram analisados os principais modos de colapso globais, com destaque nos estados limites de últimos (ELU), que podem ocorrer nesse tipo de estrutura. Além disso, elaborou-se um estudo paramétrico que teve como objetivo analisar a influência da variação do nível de protensão e da excentricidade dos cabos de protensão; bem como da metodologia construtiva (pré-tração e pós-tração) adotada para a protensão do perfil de aço que compõe a viga mista de aço e concreto. O estudo paramétrico demonstrou que em ambas as metodologias o modo de colapso predominante ocorre na 2ª Etapa de construção. Nos modelos de vigas mistas analisados com aplicação de pré-tração quando o cabo está posicionado acima da mesa inferior do perfil de aço o modo de falha ocorreu por flexo-compressão. Já para as vigas mistas avaliadas com pós-tração, independe da posição do cabo, ocorre em função do momento fletor solicitante superar o momento fletor resistente da seção. No entanto, observa-se que o nível de protensão pode ser adequadamente dimensionado de maneira que não provoque a perda da capacidade de suporte da estrutura. Observou-se ainda que independente da metodologia construtiva adotada, maiores excentricidades resultam em maior capacidade resistente para a viga de aço, corroborando os estudos expostos na revisão bibliográfica. Embora no Brasil seja pouco explorado, observou-se um amplo interesse na literatura internacional sobre o tema em questão e suas variâncias, dando origem a pesquisas teóricas e experimentais. Também se aponta como potencialidades de aplicação em projetos de novas estruturas bem como na recuperação e reabilitação de estruturas existentes.

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Střecha, Michal. « Vývoj zahraniční zadluženosti veřejného sektoru zemí EU a jeho udržitelnost ». Doctoral thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-264279.

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The public debt is considered as an important indicator of the macroeconomic and financial stability of the domestic economy. It reflects a quality of the fiscal policy and the sustainability of the public finances. The public debt has been recently paid more attention in the context of the last financial and debt crisis initiated in 2008. A considerable amount of literature has been published on the topic of interconnections between budget balances and macroeconomic environment. However, the budget deficit is only a consequence of higher public expenditures than public revenues. Therefore, the debt is only an alternative source of financing the budget deficit. One of the main ideas of the doctoral thesis is that the macroeconomic effects of the fiscal policy represented by the budget deficits and effects of the public debt should differ. While activities of the fiscal policy effect the real economic indicators such as the GDP, an increase in the public debt effects the monetary indicators such as the exchange rate, the market interest rate and the money supply. The main object of the doctoral thesis is the analysis of the public debt development including the changes in the public debt structure broken down by debt instruments, currency, maturity and the holder profile. Besides, other main object is to analyse the macroeconomic effects of various forms of a public debt; firstly the attention is paid to different monetary effects of the domestic and the external public debt. The doctoral thesis suggests a new point of view to the analysis of the macroeconomic effects and sustainability of a public debt. The findings can be used in the decision making process; If a public deficit is supposed to be domestic debt or external debt financed. Apart from the effects of the changes in the outstanding debt, the effects of the changes in the public debt structure are examined.

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Janisch, Filip. « Nosná ŽB konstrukce bytového domu ». Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226919.

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The project deals with the lower part of the construction of a residential building. The parking spaces are situated in three underground floors. The five floors occur in the over-ground part of the building. The building is based on the secant walls of Milan around the perimeter. Internal walls and columns are supported with micropiles. In this project are designed base plate, external walls and stairs. Static system and the calculation of the internal forces was carried out in Scia Engineer 2012 Student version.

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Heng, Johnny Wong Liang. « Ultimate limit state analysis of externally post-tensioned structures ». Thesis, University of Sheffield, 1997. http://etheses.whiterose.ac.uk/14442/.

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The UK Department of Transport (DoT) has recently encouraged the use of externally post-tensioned structures for bridge construction. This is due to the durability problems encountered with the conventional internally bonded post-tensioned structures. However, due to the lack of bond between the concrete and the external tendons, the ultimate strength of these structures cannot be determined by just performing a sectional analysis at the section of maximum moment. Although several recommendations have been made for the ultimate analysis of these structures, none were considered satisfactory here. Hence the purpose of this investigation is to study the flexural behaviour of these structures of all stages up to collapse, and to propose a practical methodology for estimating their ultimate strength. The study introduces eight non-linear analytical models developed for the prediction of the moment vs. deflection response of simply supported externally post-tensioned beams (with and without deviators located along their spans) up to ultimate. The models employ an iterative procedure that involves the application of loads to the structure in increments up to the collapse condition, where the curvature distribution predicted at each loading sequence is used to estimate the stress increase and variation in eccentricity in the external tendons. Second-order effects due to variation in eccentricity of external tendons and frictional behaviour of tendons at the deviators are both taken into account in these models. The eight models were then verified by comparing the results derived from them with reported experimental data, whereby good correlation was obtained. An extensive parametric study was subsequently conducted using the proposed models applied to the various parameters that influence the ultimate behaviour of externally prestressed structures Finally, the recommendations in the codes of practice for the ultimate design of these structures were also investigated here.

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Zeitouny, Joya. « Advanced strategies for ultra-high PV efficiency ». Thesis, Perpignan, 2018. http://www.theses.fr/2018PERP0056.

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La limite théorique de rendement des cellules photovoltaïques simple-jonction est de l’ordre de 33% d’après le modèle de Shockley-Queisser, ce qui reste éloigné de la limite de Carnot, prédisant une limite maximale de conversion énergie solaire → électricité de 93%. L’écart important entre ces deux limites découle des pertes intrinsèques, essentiellement liées à la conversion inefficace du spectre solaire et à la disparité entre les angles solides d’absorption et d’émission. Pour surmonter ces pertes et se rapprocher de la limite de Carnot, trois stratégies sont envisagées dans cette thèse : les cellules multi-jonction àconcentration, la combinaison de la concentration et de la restriction angulaire et les systèmes hybrides PV/CSP. Chacune de ces stratégies est limitée par des mécanismes qui dégradent leur performance.L’objectif de cette thèse est donc de comprendre dans quelle mesure les différents mécanismes limitants sont susceptibles d’affecter les performances des différentes stratégies étudiées, et d’optimiser l’architecture des cellules dans le but d’accroitre leur efficacité de conversion. Dans ce but, un modèle détaillé de cellule solaire tenant compte des principaux mécanismes limitant a été développé. Un outil d’optimisation par algorithme génétique a également été mis au point, afin d’explorer l’espace des différents paramètres étudiés pour identifier les conditions d’opération optimales. Nous démontrons l’importance majeure que revêt l’adaptation des propriétés optoélectroniques des matériaux utilisés aux conditions opératoires, que ce soit dans le cas des cellules solaires à concentration endurant des pertes résistives significatives, ou encore dans le cas de cellules solaires fonctionnant à des niveaux de températures très supérieurs à l’ambiante. Enfin, nous avons déterminé l’effet des principaux facteurs limitant que constituent les pertes résistives et les recombinaisons non-radiatives sur les cellules solairessimultanément soumises au flux solaire concentré et à la restriction angulaire du rayonnement émis
The maximum efficiency limit attainable with a single-junction PV cell is ~ 33% according to the detailed balance formalism (also known as Shockley-Queisser model), which remains far from the Carnot limit, predicting a solar to electricity efficiency upper value of 93%. The large gap between both limits is due to intrinsic loss mechanisms, including the inefficient conversion of the solar spectrum and the large discrepancy between the solid angles of absorption and emission. To overcome these losses and get closer to the Carnot limit, three different strategies are considered in this thesis: concentrated multi-junction solarcells, the combination of solar concentration and angular confinement, and hybrid PV/CSP systems. Each strategy is inherently limited by several loss mechanisms that degrade their performances. The objective of this thesis is, hence, to better understand the extent to which these strategies are likely to be penalized by these losses, and to tailor the cell properties toward maximizing their efficiencies. To address these questions, a detailed-balance model of PV cell accounting for the main loss mechanisms was developed. A genetic-algorithm optimization tool was also implemented, aiming at exploring the parameter space and identifying the optimal operation conditions. We demonstrate the uttermost importance of tailoring the electronic properties of the materials used with both multi-junction solar cells undergoing significant series resistance losses, and PV cells operating at temperature levels exceeding ambient temperature. We also investigate the extent to which series resistances losses and non-radiative recombination are likely to affect the ability of PV cells simultaneously submitted to concentrated sunlight and angular restriction of the light emitted by band-to-band recombination

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Macpherson, Maeve. « Scepticism and its limits : an investigation of contextualist strategies ». Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/scepticism-and-its-limits-an-investigation-of-contextualist-strategies(d42b41ea-be83-4c14-9eff-9a7878ed99f4).html.

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In this thesis, I investigate different Contextualist strategies for responding to the sceptical Argument from Ignorance (AI). Such responses are notable for not challenging the Principle of Epistemic Closure (widely held to be primarily responsible for the argument's conclusion). I am concerned to explore Contextualism's ability to respond to AI in a way which does not result in an uncomfortable concession to scepticism. In Part 1, I discuss Semantic Contextualism; in Part 2, I investigate how AI fares with regards to transmission of warrant when AI utilises either invariantist or Contextualist presuppositions; and in Part 3, I discuss whether Epistemic Contextualism succeeds where Semantic Contextualism fails, arguing that it does. I conclude with an endorsement of Epistemic Contextualism. Part 1: I demonstrate that Semantic Contextualism, of which I will consider three different varieties (externalist, internalist, presuppositionalist), is overly concessive to scepticism because it results in the following four difficulties: (1) knowledge attributions of the form 'I know/S knows that ~B' (where B stands for the sceptical brain-in-a-vat hypothesis) are invariably false; (2) the sceptical context is extremely easy to install; (3) scepticism is said to result from entirely ordinary epistemic practices and; (4) the sceptical context is taken to be an entirely legitimate context of ascription. I conclude Part 1 with the claim that Semantic Contextualism is overly concessive to scepticism. Part 2: Previously, Moore's Proof of an External World has been diagnosed with failing to transmit the warrant on offer for its premises to its conclusion. I argue that it is possible likewise to charge AI with transmission failure but that this cannot be done when some of the conceptual resources of Contextualism are brought to bear on AI. I show that AI can be charged with transmission failure when it is interpreted in support of invariantist (context-unrestricted) scepticism and that only when it is viewed as an argument for a context-restricted form of scepticism does it succeed in transmitting warrant. In this way, the sceptical consequences of AI are considerably reduced. Part 3: The conceptual resources newly deployed in Part 2, which show that a context-restricted, as opposed to invariantist, interpretation of AI can succeed in transmitting warrant, are borrowed from Michael Williams' Epistemic form of Contextualism. But is this form of Contextualism as concessive to scepticism as I showed Semantic Contextualism to be? I argue that it does not represent an overly concessive position vis-a-vis scepticism and therefore represents a superior Contextualist position and response to scepticism. To establish this conclusion, I interrogate the strategy and main elements of Williams' theoretical diagnosis of scepticism and his resultant version of Contextualism so as to determine the extent to which scepticism can be allayed by it. Particular attention is paid to specifying issues that Williams does not discuss, most prominently how the sceptical context has to be understood in order for it to resist his theoretical diagnosis of scepticism and what makes toleration of such resistance by context-bound scepticism reasonable. I conclude my thesis with an endorsement of Williams' Epistemic Contextualism.

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Siqueira, João Bosco de. « Limite de altas temperaturas em presença de campos externos estáticos ». Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-16102014-143540/.

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Investigamos certas propriedades físicas da teoria de campos a temperatura finita. Mostramos que, na presença de campos externos bosonicos, o limite de altas temperaturas das funções de Green pode ser obtido supondo que todas as componentes dos momentos externos sao nulas, para todas as funções de Green 1PI em ordem de um laco e em ordem de dois laços para a auto-energia. No contexto do método do campo de fundo, este resultado implica que a lagrangiana efetiva estática de um campo externo bosonico pode ser obtida calculando a pressão na presença de um campo externo independente do espaço-tempo, no limite de altas temperaturas. Aplicamos este resultado para obter a lagrangiana efetiva estática de um campo de Maxwell interagindo com um plasma da QED em ordem de dois laços. Obtivemos também a lagrangiana efetiva estática de um campo gravitacional interagindo com um campo escalar real livre, e com um plasma da QED em ordem de dois laços.
We have investigated some physical proprieties of nite temperature field theory. We have shown that, in the presence of an external bosonic field, the high temperature limit of the static Green\'s functions can be obtained assuming that all components of the external momenta are zero. This was shown to be the case for all 1PI Green\'s functions, at one-loop order, as well as for the self-energy, at two-loop order. In the context of the background field method, this result implies that the static efective Lagrangian of an external field can be obtained computing the pressure in the presence of an external field which is independent of the space-time, in the high temperature limit. We have applied this result in order to obtain the efective Lagrangian of an external Maxwell field interacting with a QED plasma at two-loop order. We have also obtained the efective Lagrangian of the gravitational field interacting with a free neutral scalar field, as well as with a QED plasma at two-loop order.

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Tenaud, Christian. « Simulation numérique de l'écoulement autour d'un manipulateur externe de couche limite ». Toulouse, ENSAE, 1988. http://www.theses.fr/1988ESAE0012.

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Étude des hypothèses avancées pour expliquer le rôle joué par les manipulateurs externes (fines lamelles immergées dans la couche limite) dans le procédé de réduction de trainée. Simulation numérique de l'écoulement. Optimisation des paramètres de la lamelle afin de définir la géométrie fournissant des gains maxima de trainée de frottement.

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Tenaud, Christian. « Simulation numérique de l'écoulement autour d'un manipulateur externe de couche limite ». Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37618826d.

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Joishi, Manoj. « Numerical investigation of particle deposition in a turbulent boundary layer with forced turbulence in the external flow ». Electronic Thesis or Diss., Université de Lorraine, 2019. http://www.theses.fr/2019LORR0251.

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Le dépôt de particules sur une paroi joue un rôle significatif dans les procédés polyphasiques fluide-solides, tels que la séparation inclusionnaire dans les poches d'acier liquide en métallurgie secondaire qui permettent de contrôler la propreté du métal avant solidification. L'objectif de ce travail est d'étudier le dépôt turbulent et la capture de particules sur une paroi, dans des situations où la turbulence au sein de la couche limite est produite à la fois par la contrainte pariétale et par les forces d'agitation du bain liquide loin de cette paroi. Les simulations sont mises en œuvre à l'échelle mésoscopique, en considérant des particules ponctuelles mais avec une turbulence complètement résolue. Un code de simulation maison a été développé, utilisant une méthode de Boltzmann sur réseau pour résoudre la dynamique de l'écoulement et en appliquant un forçage linéaire isotrope pour générer artificiellement la turbulence loin de la paroi. Le suivi lagrangien de particules permet enfin d'établir un couplage faible entre le mouvement des particules et l'écoulement turbulent. Ces techniques numériques ont été appliquées à la simulation directe d'une couche limite turbulente dans laquelle les particules de taille plus petite que l'échelle de Kolmogorov sont introduites. Les mécanismes de dépôt pour des aérosols ont été analysés et une loi statistique de vitesse de dépôt en fonction du nombre de Stokes a été extraite et comparée à la littérature. L'ensemble de ces simulations permet une meilleure compréhension des mécanismes de dépôt et de capture, en fonction de la turbulence du fluide au sein de la couche limite et des propriétés des particules. De plus, les résultats préliminaires obtenus pour des particules hydrosols, qui correspondent à des conditions qui prévalent pour des inclusions dans les poches d'acier liquide, ont montré que l'outil numérique peut être appliqué à l'étude quantitative de la capture inclusionnaire aux parois des réacteurs métallurgiques
Deposition of particles on a wall plays a significant role in fluid-solid processes such as inclusions recovery from liquid steel in ladle furnace, that controls inclusion cleanliness upstream from solidification. The aim of this work is to study the turbulent deposition and capture of particles on a wall, in a situation where turbulence in the boundary layer originates both from wall shear and from agitation in the external flow. In a ladle furnace, such an agitation would result from bubble injection. A framework for simulations at mesoscopic scale in which particles are represented as points but the turbulence is fully resolved has been developped using an in-house solver, where a Lattice Boltzmann Method (LBM) solves flow dynamics and linear isotropic forcing generates artificial turbulence. Lagrangian Particle Tracking (LPT) is used to achieve one way coupling between particle motions and turbulent flow. These numerical methods were applied to Direct Numerical simulation (DNS) of a fully developed turbulent boundary layer in which particles smaller than the Kolmogorov length scale are introduced. The deposition mechanisms in aerosol conditions have been analyzed and quantified into a statistical law for deposition velocity in terms of Stokes number, and validated against data from the literature. Such simulations have provided a better understanding of deposition and capture mechanisms, depending on the turbulent flow in a wall boundary layer and on particle physical properties. Also, preliminary simulations in hydrosol conditions that match actual ladle operation have shown that the framework developed in this work can be applied to investigate inclusion behavior in secondary steel-making although statistical analysis in this work focused on aerosols

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Yakouchyk, Katsiaryna [Verfasser], et Daniel [Akademischer Betreuer] Göler. « Post-Soviet Region, Authoritarian Stability, and Autocracy Promotion : Limits to the European Union’s External Governance / Katsiaryna Yakouchyk ; Betreuer : Daniel Göler ». Passau : Universität Passau, 2019. http://d-nb.info/1180025814/34.

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Yakouchyk, Katsiaryna Verfasser], et Daniel [Akademischer Betreuer] [Göler. « Post-Soviet Region, Authoritarian Stability, and Autocracy Promotion : Limits to the European Union’s External Governance / Katsiaryna Yakouchyk ; Betreuer : Daniel Göler ». Passau : Universität Passau, 2019. http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-6146.

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MARSILI, TOMMASO. « POTERE DI RAPPRESENTANZA E RILEVANZA ESTERNA DEL PROCEDIMENTO DECISORIO NELLE SOCIETA' DI CAPITALI ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2012. http://hdl.handle.net/10280/1549.

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La tesi concerne il potere di rappresentanza degli amministratori e la rilevanza esterna del procedimento decisorio nelle società di capitali. Dall’interpretazione della direttiva 2009/101/CE risulta un sistema che stabilisce l’opponibilità dei limiti legali e l’inopponibilità dei limiti convenzionali. Dalle limitazioni soggettive consentite dalla direttiva si ricava “per sottrazione” che il diritto europeo prevede una regola suppletiva secondo la quale il potere di rappresentanza spetta a ciascun amministratore disgiuntamente. Nel diritto interno, nel silenzio delle fonti convenzionali, la mancanza di un’espressa regola suppletiva determina l’operatività della regola suppletiva europea. La fonte del potere di rappresentanza ha natura legale ma le fonti convenzionali possono stabilire delle limitazioni soggettive opponibili ai terzi ex artt. 2383, comma 4°, e 2448 c.c. Ammessa la rilevanza esterna dei limiti legali ai poteri degli amministratori, accogliendo la tesi secondo cui nelle società di capitali la dissociazione tra potere gestorio e potere rappresentativo costituisce un elemento del modulo organizzativo legale dell’amministrazione pluripersonale, si sostiene che il mancato rispetto del procedimento decisorio sia opponibile ai terzi che la società provi essere stati a conoscenza o aver colpevolmente ignorato il vizio affettante un presupposto legale del procedimento collegiale richiesto dalla legge (art. 2388, comma 5, c.c.).
This thesis concerns the power of representation of the directors and the external relevance of the decisional process in italian companies. The Directive 2009/101/EC provides a system in which the legal limits can be invoked and the internal limits cannot be invoked with respect to third parties. From the subjective limitations allowed by the Directive is obtained "by subtraction" that European law provides a default rule, according to which every director has the power of representation separately. In domestic law, in the silence of the statute, the lack of an explicit rule determines the operation of the European default rule. The source of the power of representation has a legal nature, however the statute can determine subjective limitations that can be invoked with respect to third parties. Admitting the external relevance of legal limits on the powers of the directors and accepting the argument that in case of a board of directors the legal model provides that the decision-making power is dissociated from the power of representation, it is argued that the breach of the decisional process can be invoked if the company proves that the third party knew the lack of a legal condition of the process required by law or ignored it culpably.

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MARSILI, TOMMASO. « POTERE DI RAPPRESENTANZA E RILEVANZA ESTERNA DEL PROCEDIMENTO DECISORIO NELLE SOCIETA' DI CAPITALI ». Doctoral thesis, Università Cattolica del Sacro Cuore, 2012. http://hdl.handle.net/10280/1549.

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La tesi concerne il potere di rappresentanza degli amministratori e la rilevanza esterna del procedimento decisorio nelle società di capitali. Dall’interpretazione della direttiva 2009/101/CE risulta un sistema che stabilisce l’opponibilità dei limiti legali e l’inopponibilità dei limiti convenzionali. Dalle limitazioni soggettive consentite dalla direttiva si ricava “per sottrazione” che il diritto europeo prevede una regola suppletiva secondo la quale il potere di rappresentanza spetta a ciascun amministratore disgiuntamente. Nel diritto interno, nel silenzio delle fonti convenzionali, la mancanza di un’espressa regola suppletiva determina l’operatività della regola suppletiva europea. La fonte del potere di rappresentanza ha natura legale ma le fonti convenzionali possono stabilire delle limitazioni soggettive opponibili ai terzi ex artt. 2383, comma 4°, e 2448 c.c. Ammessa la rilevanza esterna dei limiti legali ai poteri degli amministratori, accogliendo la tesi secondo cui nelle società di capitali la dissociazione tra potere gestorio e potere rappresentativo costituisce un elemento del modulo organizzativo legale dell’amministrazione pluripersonale, si sostiene che il mancato rispetto del procedimento decisorio sia opponibile ai terzi che la società provi essere stati a conoscenza o aver colpevolmente ignorato il vizio affettante un presupposto legale del procedimento collegiale richiesto dalla legge (art. 2388, comma 5, c.c.).
This thesis concerns the power of representation of the directors and the external relevance of the decisional process in italian companies. The Directive 2009/101/EC provides a system in which the legal limits can be invoked and the internal limits cannot be invoked with respect to third parties. From the subjective limitations allowed by the Directive is obtained "by subtraction" that European law provides a default rule, according to which every director has the power of representation separately. In domestic law, in the silence of the statute, the lack of an explicit rule determines the operation of the European default rule. The source of the power of representation has a legal nature, however the statute can determine subjective limitations that can be invoked with respect to third parties. Admitting the external relevance of legal limits on the powers of the directors and accepting the argument that in case of a board of directors the legal model provides that the decision-making power is dissociated from the power of representation, it is argued that the breach of the decisional process can be invoked if the company proves that the third party knew the lack of a legal condition of the process required by law or ignored it culpably.

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Pattanayak, Soubhagya Kumar. « Role of external carbon and metal salt dosing in membrane bioreactor system to achieve limits of technology nutrient removal from municipal wastewater ». Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45672.

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Membrane bioreactor (MBR) technology in conjunction with conventional biological nutrient removal has been demonstrated to be successful in recent years. However, the limits of technology (LoT) effluent goal, ≤ 3 mg TN/L (total nitrogen) and ≤ 0.1 mg TP/L (total phosphorus), could potentially push a system to the limits of its capability. The broad objective of the long-term PhD study was to investigate role of external dosing of alum in a membrane biological nutrient removal (MBNR) system targeting LoT effluent nutrient levels. Two parallel MBNR systems, modified Bardenpho configuration, were operated under similar process conditions with metal salt addition being the only difference. The continuous flow MBNR system performance data signified the importance of external methanol and alum dosing in accomplishing the LoT nutrient removal goal. The stoichiometric methanol ratio, i.e. mg methanol required / mg NO₃-N removed, was calculated to be 6.1 in reducing average permeate NO₃-N concentration to 1.4 mg/L. Similarly, an average molar Al/TP ratio of 1.9 was required to reduce PO₄-P concentration to 0.07 mg/L in the permeate. Chemical phosphorus removal did not have any influence on COD removal, nitrification (except for a brief period) and denitrification. The relationship between chemical P removal and enhanced biological phosphorus removal (EBPR) was dynamic and was dependent on alum dosage concentration. At high dosage levels (i.e. 80 mg/L), alum supplementation competed with and finally, inhibited EBPR until the MBNR system was converted to a chemical P removal system. Activated sludge modeling was undertaken to analyze its suitability in predicting the performance of an MBNR system targeting LoT goals. The model was successful in predicting nitrogen removal, while parameter calibration was required for fitting of the measured suspended solids and EBPR data. Moreover, the model could not predict the relationship between the simultaneous biological and chemical P removal accurately. A direct batch DON measurement method, batch anion exchange resin adsorption followed by persulfate digestion, was developed and validated successfully. Using the method, the DON contribution to permeate total nitrogen was observed to vary from 7 percent to 96 percent in the parallel MBNR systems, when permeate TN concentrations were less than 3 mg/L.

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Houssier, Florian. « Le recours a l'acte a l'adolescence. Fonction de la limite entre monde interne et monde externe ». Paris 7, 1998. http://www.theses.fr/1998PA070114.

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A partir d'observations cliniques, notre propos vise a montrer comment certains adolescents commettent des actes delictueux mineurs afin de recuperer un certain rapport a la realite, externe comme psychique, qui menacait de se delier ; ces actes, contrairement au passage a l'acte, sont precedes d'un surcroit d'activite fantasmatique, notamment developpee dans la reverie diurne. Cet etat, propre a la problematique adolescente, affaiblit les limites du moi ainsi que la capacite a distinguer les espaces internes et externes. L'acte opere alors selon une double fonctionnalite : dans un premier temps, il represente une tentative d'etendre les fantasmes omnipotents du sujet a la realite ; dans un second temps, celui qui voit advenir la reponse sociale (ici une intervention judiciaire), il constitue un recours ouvrant sur la possibilite de reinterioriser des contenus symboliques a portee structurante. Sur le plan conceptuel. L'etat de la question sur la problematique de l'acte sous l'angle psychanalytique nous amene au constat suivant : les termes "acting out" et "passage a l'acte" ne rendent pas compte de la specificite de ce type de symptome. Sa dimension d'acte au service de l'homeostasie du moi, transitant par un appel au tiers, fonde notre demarche consistant a proposer une nouvelle appellation : le recours a l'acte. Celui-ci designe tout acte symptomatique dont l'apres-coup constitue un moment elaboratif qui rend pensable le passage depressif inherent a toute adolescence en cours
Based upon clinical observations, we intent to show how some adolescents commit minor unlawful acts with the intention to catch up certain relation with reality, external as well as psychic, which was a-threat of lusting. This acts, opposed to acting-out, are former of a fantasy over-activity, specially developed in the day time dream. In this state of mind, characteristic of adolescent population , diminished ego limits as well as capacity to discern internal and external spaces. Therefor, the act operates in a double function: at the beginning, it represents an attempt to extend his omnipotent ???? to reality. In a second time, that implies a social answered (here a legal intervention), constitutes a recourse allowing the reinteriorisation of symbolic contents with structuring consequences. As far as conceptual plan, the knowledge concerning the "act- problematic" seen from a psycho-analytical point of view, shows us: the notions of "passage a l'acte" and "acting out" doesn't teach us about specificity of this kind of symptoms. This act dimension, related to ego's homeostasis, that includes an external interference, explained why we try to propose a new denomination: the recourse to act. It designs all symptomatic act, which in a second time allows psychic elaboration, making possible to think about this depressive transition inherent to adolescent process

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Rainone, Corrado. « Following the evolution of metastable glassy states under external perturbations : compression and shear-strain ». Thesis, Paris, Ecole normale supérieure, 2015. http://www.theses.fr/2015ENSU0051/document.

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On considère l'évolution adiabatique des états vitreux sous perturbations extérieures. Bien que le formalisme que nous utilisons soit très général, nous nous concentrons ici sur les sphères dures en dimension infinie où une analyse exacte est possible. Nous considérons perturbations de la frontière, notamment compression ou cisaillement simple et nous calculons la réponse des états vitreux à ces perturbations : pression et contrainte de cisaillement. Nous constatons un dépassement des deux quantités avant que l'état vitreux ne devienne instable à un point spinodal, où il fond dans le liquide (ou cède). Nous estimons également la limite d'élasticité du verre. Enfin, nous étudions la stabilité des bassins vitreux vers la rupture en sous-bassins, correspondant à une transition de Gardner. Nous constatons que près de la transition dynamique, les verres subissent une transition de Gardner après une perturbation infinitésimale. Nous étudions ensuite le régime de haute pression et haut cisaillement au-delà de la transition de Gardner
We consider the adiabatic evolution of glassy states under external perturbations. Although the formalism we use is very general, we focus here on infinite-dimensional hard spheres where an exact analysis is possible. We consider perturbations of the boundary, i. e. compression or (volume preserving) shear-strain, and we compute the response of glassy states to such perturbations: pressure and shear-stress. We find that both quantities over shoot before the glass state becomes unstable at a spinodal point where it melts into a liquid (or yields). We also estimate the yield stress of the glass. Finally, we study the stability of the glass basins towards breaking into sub-basins, corresponding to a Gardner transition. We find that close to the dynamical transition, glasses undergo a Gardner transition after an infinitesimal perturbation. We then study the high-pressure and high-strain regime beyond the Gardner transition

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Popescu, Elena-Roxana. « Numerical simulation of the interaction between an external flow, laminar or turbulent, and liquid/vapor phase change ». Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0058.

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Dans le réservoir d’un satellite, le carburant cryogénique peut se transformer en vapeur à cause de la présence d’un gradient de température à la paroi, induit par le rayonnement solaire ou la diffusion thermique résiduelle des moteurs du lanceur. La quantité de vapeur transformée peut fortement augmenter la pression à l’intérieur du réservoir. En raison d’une connaissance incomplète des ces phénomènes, aujourd’hui, les opérations faites pour régulariser la pression interne entraînent une perte de carburant. Il est donc très important d’étudier le changement de phase liquide/vapeur et les processus physiques mis en jeu au niveau de l’interface. C’est dans ce contexte que se situe cette thèse, dont l’objectif est d’obtenir une meilleure compréhension des phénomènes susmentionnés au moyen de la Simulation Numérique Directe (DNS). Le travail estdivisé en trois parties : l’interaction entre un liquide à température de saturation et un écoulement externe de vapeur sous-refroidie ou surchauffée, en régime laminaire et turbulent, et l’interaction entre des mouvements de convection naturelle et le changement de phase liquide/vapeur. Tout d’abord, le régime laminaire est étudié. Dans ce cadre, une étude paramétrique est menée dont l’objectif est de trouver des lois de comportements pour le transfert thermique et le coefficient de frottement à l’interface entre un liquide statique à température de saturation et un écoulement decouche limite de vapeur. Nous étudions à la fois la vaporisation et la condensation. La seconde partie de cette thèse est dédiée à la simulation numérique d’un écoulement de couche limite turbulente d’une vapeur surchauffée en interaction avec un champ de vitesse induit par de la vaporisation. Pour cela, un injecteur de turbulence est implémenté dans le code et validé pour la configuration de l’évolution spatiale d’une couche limite turbulente sur une plaque plane avec transfert thermique. Ensuite, une étude sur l’influence du champ de vitesse induit par la vaporisation sur le nombre de Nusselt, le coefficient de frottement, le nombre de Stanton et les différentes quantités turbulentes est réalisée. Enfin, nous menons une étude numérique préliminaire sur une configuration décrivant l’écoulement convectif dans un réservoir cryogénique. Un nouveau solveur est implémenté dans le code utilisé afin de prendre en compte les variations de la densité. Des résultats préliminaires sont obtenus sur l’influence du nombre de Grashof sur le flux thermique à l’interface liquide/vapeur
In a launcher tank, the cryogenic fuel can suffer a liquid/vapor phase change due to a thermal gradient induced by solar radiation or by engines residual thermal diffusion. The quantity of vapor released by the phase change process can highly increase the internal pressure. Due to a poor knowledge of these phenomena, at present, the operations led to regulate the internal pressure induce fuel loss. It is therefore of great importance to investigate the liquid/vapor phase and the physical processes taking place at the interface. This is the context of the present thesis, thattakes place in an effort to extract better understanding of the above underlined phenomena by means of Direct Numerical Simulation (DNS). The work is split into three studies : the interaction between a liquid pool at saturation and an external flow of subcooled or superheated vapor, both in laminar and turbulent regime flows, and the interaction between natural convection mouvements and liquid/vapor phase change. Firstly, the laminar regime flow is investigated. In this framework, a parametric study is conducted with the objective of finding behaviour laws for the heat transfer and the friction coefficient at the interface between a static liquid pool at saturation temperature and a laminar boundary layer flow of vapor. Both vaporization and condensation are studied. The second project was on the numerical simulation of a turbulent boundary layer flow of superheated vapor interacting with the velocity field induced by vaporization. To this extent, a turbulent fluctuations injector is implemented and validated for the spatial development of a boundary layer flow over a flat plate with heat transfer. A study on the influence of the velocity field induced by vaporization on the Nusselt number, the friction coefficient, the Stanton number and the turbulent quantities is conducted. Finally, we lead a preliminary numerical study on a configuration describing the interaction between natural convection flow and liquid/vapor phase change in a cryogenic tank. A new solver is implemented in the in house code to account for the density variations in the liquid. Preliminary results are obtained on the influence of the Grashof number on the thermal flux at the liquid/vapor interface

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Sarembaud, Julien. « Etude de stabilité des matériaux de référence externe : méthodes de modélisation et de contrôle ». Paris, AgroParisTech, 2007. http://www.theses.fr/2007AGPT0043.

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Estournel, Claude. « Etude de la phase nocturne de la couche limite atmospherique ». Toulouse 3, 1988. http://www.theses.fr/1988TOU30042.

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Le travail realise est une etude de la couche limite atmospherique en phase nocturne (cln) basee sur l'analyse de donnees experimentales et sur la simulation numerique. Le modele utilise est unidimensionnel, il traite les transferts par un schema en coefficients d'echanges et en energie cinetique turbulente, et le transfert radiatif grace a un modele multispectral. Une nouvelle parametrisation des longueurs de melange est proposee. On utilise le modele pour etudier les caracteristiques fondamentales de la cln: le refroidissement nocturne, le profil de vent avec le jet de basses couches et la hauteur de la cln. En ce qui concerne le refroidissement nocturne on etudie le role respectif des composantes radiative et turbulente suivant la valeur du vent geostrophique. On examine le role des mecanismes qui perturbent la formation du jet nocturne: baroclinie, advection. Dans une troisieme partie, on simule des donnees experimentales. Dans des conditions de vent faible, la bonne qualite du module radiatif permet de bien simuler les profils thermiques. Dans des conditions de vent fort, on met en evidence l'influence des processus de moyenne echelle; le schema de turbulence adopte permet de retrouver les caracteristiques principales de l'evolution de la cln.

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Vehil, Raoul. « Etude de l'effet radiatif de l'aerosol dans la couche limite atmospherique ». Toulouse 3, 1987. http://www.theses.fr/1987TOU30259.

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Le travail presente est centre sur la situation ou l'effet radiatif des aerosols modifie la structure de la couche limite atmospherique. Trois situations sont etudiees: le cas des brumes seches, le cas des aerosols urbains et la cas du brouillard. La simulation numerique et l'approche experimentale conduisent au developpement ou la mise au point de programmes de calcul du transfert radiatif

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Mundim, Arnaldo Reis. « Análise comparativa da força no limite de escoamento entre um implante de peça única e os de junção hexagonal externa de diâmetros regular e estreito ». Universidade Federal de Uberlândia, 2008. https://repositorio.ufu.br/handle/123456789/16845.

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Osseointegrated implants have now been proved to be feasible. However, several factors still remain to be explained, particularly because of the large number of manufacturers and models. Although incidence is low, implant fractures are a clinical reality, and therefore researches are conducted in an endeavor to reduce their number. Objective: To test the hypothesis that the reduction in implant diameter reduces the maximum force required to attain the implant yield limit even when it is made in one piece. Materials and Methods: To test this hypothesis, three implant configurations (SIN) (n=10): HER, external hexagonal junction and regular diameter (3.75mm); HEE, external hexagonal junction and narrow diameter (3.25mm) and UNI, narrow one-piece (2.35mm) were tested. The maximum force at yield limit (N) for the implants was evaluated by means of the flexion test, with force applied perpendicular to the long axis of the implant, at the speed of 0.5 mm/min, in a mechanical test machine. The data were assed by means of the analysis of variance (ANOVA) and Tukey B tests for parametric groups (P<0.05). Results: Statistically significant differences were found between UNI and HER and HEE, and there were no statistically significant differences between the latter two. Conclusions: The UNI group presented statistically lower maximum resistance at the yield limit than the groups HEE and HER.
Os implantes osseointegrados são hoje comprovadamente viáveis. No entanto, alguns fatores ainda devem ser esclarecidos, principalmente pelo grande número de fabricantes e modelos. A fratura de implantes é uma realidade clínica, mesmo que de baixa incidência e, portanto suscita pesquisas no sentido de reluzi-las. Objetivo: Testar a hipótese de que a redução do diâmetro do implante reduz a força máxima necessária para atingir o limite de escoamento do implante de junção hexagonal externa e de diâmetro regular para o de junção hexagonal externa e diâmetro estreito e deste para o implante de peça única e diâmetro ainda mais estreito. Materiais e Métodos: Para testar esta hipótese, três configurações de implantes (SIN) (n=10): HER, junção hexagonal externa e diâmetro regular (3,75mm); HEE, junção hexagonal externa e diâmetro estreito (3,25mm) e UNI, peça única estreito (2,35mm) foram testados. A força máxima no limite de escoamento (N) para os implantes foi avaliada por meio do ensaio de flexão, com força aplicada perpendicular ao longo eixo do implante, em máquina de ensaio mecânico na velocidade de 0,5 mm/min. Os dados foram avaliados por meio de teste de análise de variância (ANOVA) e Tukey B, para grupos paramétricos (P<0.05). Resultados: Foram encontradas diferenças estatisticamente significantes entre UNI e HER e HEE, sendo que não houve diferenças estatisticamente significantes entre os dois últimos. Conclusões: O grupo UNI apresentou resistência máxima no limite de escoamento estatisticamente inferior aos grupos HEE e HER.
Mestre em Odontologia

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Rodrigues, Julio. « A inserção da Guiné-Bissau na União Econômica e Monetária Oeste Africana (UEMOA) : limites e oportunidades para o desenvolvimento socioeconômico do país (1997-2013) ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/147369.

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Um dos aspectos mais importantes da nova realidade internacional é a tendência à formação de blocos regionais. A criação dos blocos ao redor do mundo representa uma estratégia de promoção do desenvolvimento para os países da periferia e, sobretudo, para os Estados africanos que são caracterizados por uma história peculiar de marginalização, países com pobreza e miséria dramáticas, ciclos de instabilidades política e militar, sequelas de séculos de explorações promovida por diversas potências. Como forma de resolver parte dos problemas que afetam o continente, os dirigentes africanos acreditam na integração econômica e política como uma das alternativas. Tratando-se dos países do oeste africano, a integração possibilita uma coordenação conjunta na solução dos problemas internos da região e nos desafios da globalização. O objetivo desta tese é de analisar a inserção da Guiné-Bissau na UEMOA. Neste sentido, o trabalho se propõe responder duas perguntas: em que medida a UEMOA pode contribuir para o desenvolvimento econômico e social guineense e quais são as vantagens e as desvantagens da Guiné-Bissau na UEMOA. Ele parte da hipótese de que a referida união é bastante útil para o país lusófono na medida em que oferece um enorme suporte na sua política monetária e fiscal, sem falar na abertura de novos mercados, embora o ciclo da instabilidade política tenha se constituído num dos principais obstáculos para o desempenho guineense no bloco. Ressalta-se que o presente trabalho foi construído com base nas consultas de diversas obras bibliográficas, e também, durante a construção desta tese, viajamos para o referido país que constitui objeto do nosso estudo, onde obtivemos alguns dados primários através do contato que tivemos com diversos dirigentes do país ligado ao tema. Entretanto, conclui-se que a inserção da Guiné na UEMOA aconteceu de forma precipitada sem que houvesse estudos aprofundados. Embora o país, por um lado, tenha alcançado um dos objetivos que é de estabilizar os preços ou controlar a inflação, assim como encontrou, na união, uma importante fonte de financiamento, o BOAD (Banque Ouést Africaine de Dévelopment), para desenvolver, reabilitar e modernizar as suas infraestruturas. Por outro lado, o desempenho guineense naquele bloco tem sido afetado pelo ciclo de instabilidades que tem dificultado a elaboração de uma estratégia que permitiria a obtenção de ganhos, seja por via do comércio internacional ou pela captação do investimento estrangeiro; com isso, o país se tornou dependente dos seus parceiros do bloco.
One of the most important aspects of the new international reality is the tendency to form regional blocks. The creation of blocks around the world is a development promotion strategy for the periphery countries and, especially to the African states, which are characterized by a peculiar history of marginalization, countries with dramatic poverty and misery, cycles of political and military instabilities, consequences of centuries of explorations promoted by many colonial powers. As a way to solve part of problems that affect the continent, African leaders, believe in economic and political integration as one of the alternatives. Concerning West African countries, the integration enables to joint coordination in solving the internal problems of the region and the challenges of globalization. This thesis aims to analyze the inclusion of Guinea-Bissau in the West African Economic and Monetary Union (WAEMU). Thus, the work aims to answer two questions: to what extent WAEMU can contribute to economic and social development of Guinea-Bissau, and what are the advantages and disadvantages of Guinea-Bissau in the WAEMU. It starts from the assumption that such union is very useful for the Portuguese-speaking country, once it offers a huge support in its monetary and fiscal policy, not to mention the opening of new markets, although the cycle of political instability has been one of the main obstacles to Guinea-Bissau performance in the block. It is noteworthy that this work was done in the basis of research in various literature works, and during the construction of this thesis, we traveled to the country, which is the object of our study, where we obtained some primary data through the contact we had with several leaders of the country related to the subject. However, it is concluded that the inclusion of Guinea - Bissau in WAEMU happened rashly without in depth studies. Although the country on one hand, has achieved one of its goals to stabilize prices and control inflation, as found in union an important source of funding, the BOAD (Banque Ouest Africaine de Development) to develop, rehabilitate and modernize its infrastructure. On the other hand, the performance of Guinea-Bissau in the block has been affected by the instabilities cycle that has hampered the development of a strategy that would allow the development gains, either through international trade or through the capture of foreign investment; with this, the country became dependent on its partners in the block.

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Olivero, Philippe. « Etude expérimentale des fluctuations de pression pariétale sous une couche limite turbulente en aval d'un dispositif de deux manipulateurs externes de type profil aviation plaçés en tandem ». Aix-Marseille 2, 1990. http://www.theses.fr/1990AIX22079.

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L'alteration d'un ecoulement de couche limite par un dispositif de deux manipulateurs externes de type profils d'aile, places en tandem, est evaluee par la mesure des caracteristiques moyennes et turbulentes. Les resultats montrent que la structure de la couche limite manipulee reste en moyenne similaire a celle d'une couche limite naturelle. La reduction du frottement local mesure, atteint un maximum de 20% a 36 epaisseurs de couche limite a l'aval du dispositif et persiste jusqu'a 100 epaisseurs de couche limite, ou elle vaut encore 10%. L'utilisation de techniques de decontamination acoustique, a deux ou quatre capteurs, ameliore la description de la partie convective du champ de pression parietale. La mesure des densites auto et interspectrales montre qu'elles sont reduites en proportion du frottement parietal dans les hautes frequences alors que dans les basses frequences, leur comportement depend de la position de mesure: niveau spectral plus reduit que le frottement avant la zone de reduction maximale du frottement et moins reduit que le frottement dans la zone de relaxation. A l'abscisse de la reduction maximale du frottement, le niveau des petits nombres d'onde, mesure par alignement microphonique, presente une reduction superieure a ce que prevoit une similitude relative au frottement. Des techniques d'analyse par moyennes conditionnelles sont developpees afin de mettre en evidence le lien existant entre le champ de fluctuations de pression parietale et les mecanismes producteurs de turbulence dans la couche limite, susceptibles d'etre preferentiellement alteres par la manipulation

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Said, Frédérique. « Etude expérimentale de la couche limite marine : structure turbulente et flux de la surface (expérience TOXANE-T) ». Toulouse 3, 1988. http://www.theses.fr/1988TOU30022.

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Le travail presente est une etude experimentale des transferts turbulents de chaleur, humidite et quantite de mouvement dans la couche limite marine. La phase experimentale (experience toscane-t) s'est deroulee en mars 1985, au large de la baie d'audierne (finistere). Le principal vecteur utilise pour le travail presente est un avion instrumente pour la physique de l'atmosphere. Ce moyen a permis de determiner une topographie des caracteristiques turbulentes, sur une echelle horizontale de l'ordre de 50km sur 50km, et de calculer les flux par la methode des correlations. Les conditions experimentales rencontrees correspondent a des vents compris enre 3 et 12 metres par seconde et a des conditions d'instabilite caracterisees par des longueurs de monin obukhov negatives comprises entre 50 et 300 metres. La structure turbulente de la couche limite marine est presentee dans le cadre de la theorie de similitude. Les resultats obtenus sont en accord avec les donnees acquises en couche limite dynamique, marine ou continentale. Ils sont egalement compares aux caracteristiques turbulentes des couches limites convectives. La finalisation de cette etude est resumee au moyen d'une parametrisation des flux de surface. Celle-ci est utilisable dans les modeles de grande echelle et consiste a calculer les coefficients aerodynamiques. Dans les conditions experimentales de l'etude les valeurs obtenues sont les suivantes: 1. 8 10**(-3) pour la quantite de mouvement (cd::(10)); 1. 5 10**(-3) pour la chaleur sensible (ct::(10)); et 1. 5 10**(-3) pour la chaleur latente (cq::(10)); ces coefficients sont independants de l'echelle d'integration spatiale a laquelle ils ont ete determines (de 5 km sur 5 km a 50 km sur 50 km).

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Štramberský, Martin. « Návrh předpjaté nádrže ». Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226967.

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The matter of this diploma thesis is a static storage tank for petroleum substances, the study of a solution for appropriate shape of shell and its effort to dihedral for roofing, and the study of effect of the storage of inner roofs walls of the tank to the size of the internal forces. The internal walls are carried out by the method of finite elements in the engineering program Scia Engineering 2013 and on the basis of it, designing of the framing sections of the tank. There is a calculation part of the lower horizontal bias wreaths of the shell and internal supporting wall. All the components are assessed on the 1st limit state of the load-bearing capacity and the 2nd limit state of the application (emergence cracks, limiting voltage in the concrete and a prestressing steel). The existing external wall is assessed only on the marginal status load of carrying capacity. The part of diploma thesis is also drawing documentation, accompanying report and technical report. The goal of the diploma thesis was to design the tank without an occurrence of the cracks in the concrete so as the vertical wall was prestressing only in the horizontal direction and the optimal proposal roof tanks as an addition.

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Andrade, Débora de Assis Pacheco. « Limites do controle do Tribunal de Contas da União sobre contratações públicas ». Pontifícia Universidade Católica de São Paulo, 2016. https://tede2.pucsp.br/handle/handle/7035.

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Made available in DSpace on 2016-04-26T20:24:16Z (GMT). No. of bitstreams: 1 Debora de Assis Pacheco Andrade.pdf: 1091471 bytes, checksum: f9f98737623e336f649988b3efc20f8b (MD5) Previous issue date: 2016-03-03
This study analyzes whether the external control exercised by the Brazilian Federal Court of Auditors (Tribunal de Contas da União) on administrative contracts is within its constitutional and infra constitutional competences. The analysis of cases judged the by Brazilian Federal Court of Auditors in the last five years shows that their practice is not fully consistent with the constitutional and legal basis, basically due to the following evidence: decisions on such matters which go beyond the financial-budget issue; which review discretionary choices of the public administrator and that interfere in contractual arrangements concluded between the public authorities and the private parties. Indeed, it was noted that the Brazilian Federal Court of Auditors, imbued with the relevant mission to protect the public treasury and to contribute to the improvement of public administration, has expanded its activities beyond the examination of accounts, trespassing exclusive competes of the executive and legislative powers. On the other hand, a tendency to approximate the public administrator and the contracted party was noted in the Brazilian Federal Court of Auditors, revealing a change in its institutional nature marked by a punitive character to a conciliatory and collaborative approach. This shift in the focus of the Brazilian Federal Court of Auditors can operate as an important inducer of the national economic development, as long as limited to matters within its jurisdiction and respecting administrative choices
O presente estudo avalia se o controle exercido pelo Tribunal de Contas da União sobre os contratos administrativos encontra guarida nas suas competências constitucionais e infraconstitucionais. A análise de julgados prolatados pelo Tribunal de Contas da União nos cinco últimos anos revela que a sua atuação não se coaduna plenamente com as bases constitucionais e legais, em virtude, basicamente, das seguintes evidências: decisões que recaem sobre matéria que extrapolam a temática financeiro-orçamentária; que revisam escolhas discricionárias feitas pelo administrador público e que interferem em cláusulas contratuais celebradas entre o Poder Público e o particular. Com efeito, notou-se que o Tribunal de Contas da União, imbuído da relevante missão de salvaguardar o patrimônio público e de contribuir para o aprimoramento da gestão pública, expandiu a sua atuação para além do exame das contas, invadindo esferas que competem exclusivamente aos Poderes Executivo e Legislativo. Por outro lado, notou-se haver no Tribunal de Contas da União uma tendência de se aproximar do administrador público e do contratado, revelando uma alteração na sua natureza institucional, marcada pelo caráter sancionatório, para uma postura conciliadora e colaborativa. Essa mudança no eixo de atuação do Tribunal de Contas da União, se adstrita às matérias da sua jurisdição e respeitadas as escolhas administrativas, pode operar como um importante indutor do desenvolvimento econômico nacional

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Croquet, Nicolas A. J. « Formal and substantive covergence between the European Court of Human Rights and the ad hoc International Criminal Tribunals in the treatment of implied external limits upon defence rights : towards global legal uncertainty in the use of generic and specific ». Thesis, University of Oxford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.539950.

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Barthomeuf, Marie-Odile. « Etude par simulation de la chimie en phase gazeuse d'une couche limite atmospherique : influence des hydrocarbures legers et des hydrocarbures naturels sur la formation d'oxydants ». Toulouse 3, 1988. http://www.theses.fr/1988TOU30098.

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La chimie en phase gazeuse des basses couches de l'atmosphere est regie par le cycle reactionnel des oxydes d'azote et des hydrocarbures. Les oxydes d'azote ont une origine anthropogenique liee aux combustions et aux activites industrielles et une origine naturelle liee a l'activite bacterienne des sols. De meme, pour les hydrocarbures, on note une composante anthropogenique et une composante naturelle due a des emissions a partir de la vegetation. Le travail presente a consiste a developper un modele lagrangien de chimie de l'atmosphere etudiant le comportement des gaz traces dans une atmosphere peu polluee, en presence d'hydrocarbures legers et naturels. Ce modele etudie l'evolution du profil vertical des composants dans une masse d'air se deplacant dans le sens de l'advection au-dessus d'une source homogene de grande surface, dans le cas d'une situation anticyclonique. Il traite a la fois l'aspect dynamique, parametrise par un profil de coefficients de diffusion, kz, variable en fonction du temps, et l'aspect chimique du probleme, qui considere les reactions en phase gazeuse homogene et comporte les chaines reactionnelles des oxydes d'azote et des hydrocarbures legers et naturels. L'introduction d'hydrocarbures legers dans le schema reactionnel conduit a une formation d'ozone d'autant plus importante que les teneurs en oxydes d'azote sont fortes. Pour de faibles sources de nox, l'introduction d'hydrocarbures biogeniques se traduit par un puits d'ozone, tandis que pour de fortes sources de nox, on note un accroissement des concentrations dans la masse d'air. L'introduction d'hydrocarbures legers et biogeniques se traduit egalement par une diminution des teneurs en hno::(3) et une augmentation des teneurs en produits pernitrates dans la masse d'air. Il ressort de cette etude que la cinetique chimique influe essentiellement sur l'evolution des concentrations des differents produits tandis que la dynamique, transfert vertical et depot au sol joue sur l'evolution de leur profil vertical

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Martinez, Hugo. « Contribution à la modélisation du transport éolien de particules : mesures de profils de concentration en soufflerie diphasique ». Université Joseph Fourier (Grenoble), 1996. http://www.theses.fr/1996GRE10032.

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Ce travail traite de l'utilisation des outils de modelisations physique et numerique dans le domaine du transport eolien de differentes particules. La modelisation physique en soufflerie diphasique et la theorie de la couche limite turbulente ont permis de reproduire les conditions de transport in situ. Dans le cadre de cette approche, nous avons concu et mis en place un dispositif optique de visualisation laser, et une chaine de prise et de traitement d'images pour la determination des profils de concentration massique de l'ecoulement charge. La phase transitoire qui mene vers la saturation est etudiee. L'influence des caracteristiques des particules sur les profils de concentration est aussi analysee. Cette technique de mesure non intrusive donne des resultats tres encourageants par rapport aux profils prevus par la theorie, et permet d'obtenir un nombre de points de mesure tres important. Une simulation numerique basee sur les lois de conservation de la mecanique des fluides est presentee. L'interaction entre l'ecoulement et le lit de particules est prise en compte par l'intermediaire d'un flux massique determine experimentalement, grace a un dispositif optique (diode laser) qui permet de mesurer l'evolution de l'epaisseur du lit de particules. Ces observations experimentales donnent lieu a une analyse du phenomene de ripples observe lors de l'evolution temporelle de l'epaisseur du lit. Une premiere simulation par le code flow3d (cfds-aea technology, angleterre) indique une bonne reproduction des champs de vitesses. Cependant, meme si les ordres de grandeur pour les profils de concentration sont corrects dans les premiers millimetres, ce code numerique ne permet pas d'obtenir une diffusion verticale suffisante des particules. Une seconde approche numerique permet de resoudre l'equation de conservation de la masse solide dans la zone de suspension, et donne une distribution spatiale de la concentration tres proche de la distribution experimentale

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Lazarre, Joëlle. « Modélisation 3D de l'interface socle varisque - couverture alpine dans le massif du Pelvoux (Hautes Alpes, France) : tectonique des socles et des bassins à la limite secondaire - tertiaire ». Phd thesis, Université Claude Bernard - Lyon I, 1997. http://tel.archives-ouvertes.fr/tel-00614882.

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Le massif du Pelvoux (MCE, Alpes occidentales) fait partie de la paléo-marge passive téthysienne. C'est un site privilégié d'étude de structures superposées. On y trouve trace d'événements extensifs téthysiens, puis compressifs alpins. Les massifs de Morges, des Pourroys et du Vallon sont des pincées de couverture mésozoïque dans le socle cristallin. Ils permettent une étude des relations entre le socle et sa couverture. Cet interface est un marqueur de la déformation finie à l'échelle orogénique. Géométrie et cinématique montrent l'existence de deux phases de déformation dans l'histoire alpine. Un calage dans le temps est proposé par comparaison avec les régions environnantes: la phase DI serait du Crétacé supérieur - Eocène inférieur (pyrénéo-provencale). La D2 est au plus vieux oligocène supérieur. Elle s'intègre au modèle géodynamique par rotation-expulsion si l'on abaisse la pointe de l'indenteur d'environ 10 km vers le Sud. Le socle accommode le raccourcissement DI vers le SW par des plis kilométriques, alors que la couverture développe des plis PI de toute échelle. Ce découplage mécanique est en partie contrôlé par la distribution des fluides. ils sont diffus dans la couverture, mais chenalisés dans le socle dans les grands accidents mylonitiques. La déformation est alors concentrée le long de ces zones de faiblesse. Cette tectonique est contemporaine de conditions de température de 300 à 400°C et de profondeur de 5 à 12 km. Le raccourcissement Dl structure le massif. Cette hypothèse sur la géométrie 3D du massif de Morges a été illustrée par un modèle surfacique construit avec le modeleur STRIM. Il a été ensuite exploité pour un dépliage. Une autre méthode de reconstruction des surfaces a fourni des résultats corroborant ceux obtenus avec STRIM. Un apport de cette étude est de montrer dans le Sud-Pelvoux une absence de cisaillement plat au profit d'accidents verticaux. Cette géométrie s'intègre à celle déduite du profIl sismique ECORS pour la zone externe des Alpes.

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Bua, G. « THE EFFECT OF INTERNATIONAL POLICIES ON BORROWING AND DEBT OF DEVELOPING COUNTRIES ». Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/259794.

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The first paper introduces a new dataset on the stock and structure of domestic debt in 36 Low-Income Countries over the period 1971-2011. We characterize the recent trends regarding LICs domestic public debt and explore the relevance of different arguments put forward on the benefits and costs of government borrowing in local public debt markets. The main stylized fact emerging from the data is the increase in domestic government debt since 1996. We also observe that poor countries have been able to increase the share of long-term instruments over time and that the maturity lengthening went together with a decrease in borrowing costs. However, the concentration of the investor base, mainly dominated by commercial banks and the Central Bank, may crowd out lending to the private sector.

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Barrois, Olivier. « Assimilation de données et modélisation stochastique dans la réanalyse des données géomagnétiques satellitaires ». Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAU030/document.

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Cette thèse, intitulée "Assimilation de données et modélisation stochastique dans la réanalyse des données géomagnétiques satellitaires", propose de retrouver des informations sur l'état du noyau terrestre à la frontière noyau-manteau, en combinant, d'une part, des contraintes spatiales issues de modélisations numériques directes, et d'autre part, des informations temporelles provenant d'équations stochastiques.Cet objectif est réalisé grâce à l'utilisation de méthodes inverses, et à la construction d'un algorithme d'assimilation de données à état augmenté.L'algorithme répond à la double volonté d'être flexible, c'est-à-dire de pouvoir intégrer plusieurs sources de données ou d'informations, et simple d'utilisation, c'est-à-dire d'être peu coûteux en temps de calcul et facilement modifiable.Ce travail s'inscrit dans la continuité des études menées par la communauté en assimilation de données géomagnétiques, ainsi que dans l'opportunité d'utiliser les dernières données satellitaires provenant de la récente mission Swarm (2014-....).Il a été effectué en collaboration avec Julien Aubert (IPGP), qui a fourni les contraintes spatiales issues du modèle Coupled-Earth, ainsi qu'avec Christopher C. Finlay (DTU) et Magnus Hammer (DTU), qui ont fourni les données satellitaires et d'observatoires au sol.Les principaux aboutissements de cette thèse sont la conception d'un algorithme simple et fonctionnel, validé lors d'expériences jumelles synthétiques (publié), et appliqué tout d'abord aux coefficients de Gauss d'un modèle géomagnétique, avant d'être étendu vers les données satellitaires des missions CHAMP et Swarm.Mon algorithme est capable de retrouver de l'information sur les quantités mesurées du noyau mais également sur des quantités non-observées telles que les écoulements du fer liquide ou la diffusion magnétique.Ce travail amène également à la production d'un modèle de champ magnétique et de champ de vitesse à la frontière noyau-manteau qui n'est pas classiquement régularisé.Ce modèle géomagnétique montre des résultats globalement similaires au modèle de référence CHAOS-6, et est cohérent avec les autres travaux de la communauté.Ainsi, les cartes de champ magnétique et de vitesse obtenues à la surface du noyau attestent que le champ magnétique est majoritairement dirigé par l'advection, et confirment la présence persistante d'un gyre équatorial associé avec un hémisphère Pacifique plus calme mais plus dynamique pour le champ de vitesse.La diffusion magnétique retrouvée est concentrée sous l'Indonésie et l'Océan Indien.Fondamentalement, ma thèse démontre l'importance de la prise en compte des erreurs de modélisation dans l'assimilation de données géomagnétiques, avec l'apparition de biais importants et une sous-estimation des erreurs a posteriori lorsque ces erreurs sont négligées.Finalement, le travail présenté tout au long de ce manuscrit restant préliminaire, il ouvre la voie vers une utilisation accrue des mesures géomagnétiques, avec notamment la future publication d'un code libre qui permettra la comparaison systématique des résultats obtenus avec ceux de la communauté
This thesis, entitled {sc Data Assimilation and Stochastic Modelling in Geomagnetic Satellite Data Reanalysis}, intends to retrieve information on the state of the Earth's core at the Core-Mantle-Boundary, by combining, first, spatial constraints coming from direct numerical simulations, and second, temporal information coming from stochastic equations.This purpose is achieved through inverse methods and a data assimilation augmented state algorithm.The proposed algorithm is designed to be flexible, textit{i.e.} able to integrate several types of data or constraints, and to be simple, textit{i.e.} with low computation time and easy to modify.This work fits in with the other studies on the geomagnetic data assimilation of the community, and with the opportunity to use the last satellite data from Swarm spacecraft (2014-....).We have worked in collaboration with Julien Aubert (IPGP), who has provided the spatial constraints from Coupled-Earth dynamo, and with Christopher C. Finlay (DTU) and Magnus Hammer (DTU), who have provided the satellites and ground observatories data.The major outcomes of this thesis are the design of a functional algorithm, validated through synthetic twin experiments (published), and applied, first, to the Gauss coefficients of a geomagnetic model, and second, to the measures of the CHAMP and Swarm missions.My algorithm is able to retrieve information, not only on the measured quantities, but also on the unobserved quantities like the core flows or the magnetic diffusion.This work has led to the production of a magnetic field and core flows model at the core surface which is not classically regularized.The geomagnetic field model shows results that are globally similar to the CHAOS-6 reference field model, and that are coherent with the other studies of the community.Thus, the maps of the magnetic field and the velocity field obtained, confirm that the dipole decay is principally driven by advection, and display the persistent presence of the Atlantic gyre associated with a Pacific hemisphere less energetic.The inverted magnetic diffusion is concentrated under Indonesia and Indian Ocean.Fundamentally, my thesis demonstrate the importance of taking into account the modelling errors in the geomagnetic data assimilation, which leads to strong biases and an underestimation of the textit{a posteriori} errors when those errors are neglected.Finally, the work presented in this manuscript is preliminary, and it paves the way toward an increased use of the satellite data, with in particular, the free release of my code in order to compared the results with the ones obtained by the community

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Cautenet, Guy. « Possibilites et limites d'utilisation de l'equation du bilan d'energie pour la determination des echanges au sol en zone tropicale avec des donnees de routine ». Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF2E392.

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Le theme de ce travail est l'etablissemnt du bilan d'energie a l'interface sol-atmosphere en zone tropicale a l'aide de donnees meteorologiques conventionnelles. Etablir le bilan d'energie en un site revient a estimer les divers flux d'energie en ce point: flux de chaleur sensible et de chaleur latente, rayonnement net et flux de chaleur dans le sol. La necessite d'estimer ce bilan en routine a l'echelle journaliere (pour l'agrometeorologie, par exemple) impose l'utilisation de donnees de routine du reseau conventionnel (tel le reseau asecna en afrique de l'ouest) en entree d'un modele numerique de surface approprie. Le but de ce travail est de justifier cette demarche. Tout d'abord, on presente des donnees micrometeorologiques recueillies dans une zone de savane de l'afrique de l'ouest. Il s'agit de mesures de precision des donnees aerologiques primaires (temperature et humidite de l'air, vent) et des flux d'energie au sol. On montre ensuite comment ces donnees ont servi a qualifier des modeles de surface, les premieres comme donnees d'entree, les secondes comme etalon de comparaison modele/mesures. Ces tests ont ete conduits dans diverses conditions meteorologiques, d'humidite du sol et de couvert vegetal. Ils ont permis de qualifier un modele de surface simple en vue de l'etablissement du bilan: calculs et mesures concordent avec des ecarts de 10 a 20% en moyenne journaliere. Enfin, les donnees de routine d'une station asecna ont ete qualifiees pour les calculs de bilan: les tests ont montre qu'elles pouvaient etre utilisees en entree du modele precedemment valide sans alterer la precision des estimations des moyennes journalieres des flux de facon sensible, ce qui permet de conclure que le bilan energetique local moyen de la surface peut etre etabli ainsi en routine

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Aelbrecht, Denis. « Étude expérimentale de la rectification d'un écoulement alternatif pariétal en milieu tournant et de la turbulence d'une couche d'Ekman oscillante : application aux courants de marée en Manche orientale ». Université Joseph Fourier (Grenoble ; 1971-2015), 1995. http://www.theses.fr/1995GRE10103.

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La rectification d'un ecoulement de fluide homogene force alternativement sur un fond plat horizontal et le long d'une paroi verticale en milieu tournant est etudie experimentalement. On montre comment les echanges de quantites de mouvement entre la couche d'ekman et la couche limite contre la paroi provoquent une interaction non lineaire forte entre les composantes horizontales du courant, qui engendre un courant residuel significatif le long de la paroi. Ce courant laisse la paroi verticale sur sa droite dans le cas d'une rotation correspondant a l'hemisphere nord. Les caracteristiques de ce courant residuel, ou rectifie, sont determinees a l'aide de techniques de visualisation et de mesure velocimetrique. L'evolution parametrique du phenomene est confrontee avec une modelisation theorique de l'ecoulement et avec des simulations numeriques. L'existence d'un courant residuel cotier le long des cotes francaises de la manche orientale rend pertinente l'application de notre etude aux courants de maree de cette region. On etudie ensuite la transition vers la turbulence de la couche d'ekman presente sous l'ecoulement alternatif force. Des reseaux d'ondes d'instabilite peuvent apparaitre, puis interagir si le nombre de reynolds est grand, ou encore se detruire au moment de la renverse du courant. Ces explosions engendrent un melange vertical important. Des mesures de fluctuations des vitesses, realisees au film chaud, confirment les observations. On peut encore envisager d'appliquer ces resultats a la turbulence de fond des courants de maree dans la manche

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Le, Luyer Mona. « Évolution dentaire dans les populations humaines de la fin du Pléistocène et du début de l’Holocène (19000 – 5500 cal. BP) : une approche intégrée des structures externe et interne des couronnes pour le Bassin aquitain et ses marges ». Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0003/document.

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À partir de la fin du Pléistocène, une réduction de la taille des dents humaines et une simplification morphologique ont été observées et débattues en lien avec des changements culturels et environnementaux. Suite à de nouvelles découvertes et à la révision des contextes archéologiques de certains gisements, une réévaluation de la nature des variations de plus de 1900 couronnes dentaires est proposée pour 176 individus de la fin du Paléolithique, du Mésolithique et du début du Néolithique provenant du Bassin aquitain et de ses marges. Particulièrement, les variations de la structure interne (épaisseur de l’émail, proportions des tissus dentaires, morphologie de la jonction émail-dentine) ont été évaluées de manière non invasive grâce aux méthodes d’imagerie 3D (microtomographie) et de morphométrie géométrique afin de caractériser et d’interpréter l’évolution des couronnes dentaires selon une approche intégrée. Les résultats des analyses morphométriques montrent une discontinuité entre les populations de la fin du Pléistocène et celles du début de l’Holocène. Une réduction des dimensions externes, des épaisseurs de l’émail et des proportions des tissus est mesurée entre la fin du Paléolithique et le Mésolithique, alors que des différences majeures dans les types d’usure et la distribution de l’émail sont observées entre le Mésolithique et le Néolithique. Ces données suggèrent que les modifications induites par les changements environnementaux de l’Holocène ont eu un impact plus important sur la réduction dentaire dans les populations humaines et que les changements culturels néolithiques ont surtout affecté la distribution de l’émail. Enfin, une corrélation entre le type d’usure occlusale et la distribution de l’épaisseur de l’émail a été mise en évidence et associée à des changements de régime alimentaire. En particulier, l’épaisseur de l’émail peut évoluer rapidement comme une réponse sélective aux changements fonctionnels dans la biomécanique de la mastication
Since the Late Pleistocene, a reduction in size and a morphological simplification of human teeth have been observed and arguably linked to cultural and environmental changes. Following new discoveries along with the revision of key archaeological contexts, a re-assessment of the nature of crown variations on more than 1900 teeth is proposed for 176 Late Paleolithic, Mesolithic and Early Neolithic individuals from the Aquitaine Basin and its margins. In particular, a non-invasive assessment of internal tooth structure variability (enamel thickness, dental tissue proportions, enamel-dentine junction morphology) has been performed using 3D imaging methods (microtomography) and geometric morphometrics in order to characterize and interpret dental evolution from a whole crown perspective. Results from the morphometric analyses show a discontinuity between Late Pleistocene and Early Holocene populations. External dimensions, enamel thicknesses and tissue proportions are reduced in Mesolithic individuals compared to those of the Late Paleolithic, while major differences are observed in occlusal wear patterns and enamel distribution between Mesolithic and Early Neolithic samples. These data suggest that environmentally-driven modifications during the Early Holocene had a major impact on dental reduction in human populations and that Neolithic cultural changes had mostly affected enamel distribution. Finally, a correlation between occlusal wear pattern and enamel thickness distribution is observed and associated with dietary changes. In particular, enamel thickness may have rapidly evolved as a selective response to functional changes in masticatory biomechanics

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Dandouras, Jean. « Etude de la dynamique de la queue de la magnetosphere terrestre et des conditions de declenchement des sous-orages magnetospheriques ». Toulouse 3, 1988. http://www.theses.fr/1988TOU30191.

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Les differentes signatures des sous-orages causes par des populations variees de plasma qui constituent la magnetosphere sont etudiees statistiquement. Les decroissances transitoires des flux de particules associes a ces sous-orages sont interpretees en terme d'amincissement de la couche de plasma. Des correlations avec le phenomene d'injection de particules energetiques dans la partie interne de la magnetosphere cote nuit sont mises en evidence. Ceci permet de developper un modele decrivant le processus physique responsable a la fois des amincissements et des injections

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Marroni, Etiene Villela. « Política internacional dos oceanos : caso brasileiro sobre o processo diplomático para a plataforma continental estendida ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/88350.

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A diversidade do uso do espaço oceânico e a antiga concepção da “doutrina da liberdade dos mares” forçou uma readequação do ordenamento político-econômico e espacial do ecossistema oceânico. Este redirecionamento, que envolveu o sistema internacional, originou uma nova geopolítica ou uma nova ordem global para o planejamento espacial oceânico, nos termos da Convenção das Nações Unidas sobre o Direito do Mar (CNUDM). Em razão de tais alterações, contextualizar-se-á a história do mar territorial brasileiro, em 1970, e suas implicações políticas nacionais e internacionais. Após, serão averiguadas as coalizões integradas pelo Brasil em uma aparente “batalha diplomática”, que se estendeu além de nove anos, envolveu mais de 130 países e originou um dos tratados mais bem sucedidos da história: a Convenção das Nações Unidas sobre o Direito do Mar. A partir de então, dentre outras conquistas, os Estados Partes garantiram o seu direito legal ao solo e subsolo marinho, mediante submissões para a plataforma continental além das 200 milhas náuticas, definidos no artigo 76 da Convenção. Tal conquista possibilitou aos países em desenvolvimento e a pequenas nações insulares acesso a valiosos recursos naturais, como o petróleo, gás e minerais. Os Estados costeiros, signatários da Convenção, passaram a ter assegurado o direito de reivindicar seu território submerso, ou a plataforma continental estendida, para até 350 milhas náuticas. Com a nova regulamentação, a análise das submissões passou a ser feita pela Comissão de Limites da Plataforma Continental (CLPC), organismo derivado da CNUDM, onde especialistas, selecionados segundo o critério de equidade geográfica, aceitam, modificam ou rejeitam as reivindicações. Demonstrar-se-á procedimentos adotados por Estados costeiros (insulares ou arquipelágicos) ao solicitar a ampliação de seus limites oceânicos, o modo dos especialistas brasileiros trabalharem a ampliação da plataforma continental estendida e de que forma foi feito o planejamento e o gerenciamento em termos políticos, através da Comissão Interministerial para os Recursos do Mar. Finalmente, averiguar-se-á se o Governo do Brasil terá condições de assumir tal responsabilidade, considerando o possível aumento de suas fronteiras e a capacidade do Estado, em termos científicos, tecnológicos e políticos, de internalizar e cumprir os preceitos da Convenção em sua política nacional para o mar.
The diversity of uses of the oceanic space and the old conception of “freedom of the seas doctrine” has compelled an adaptation of the political-economic and spatial legal framework for the oceanic ecosystem. This changing of direction encompassed the international system and has given rise to a new geopolitics for the legal framework of oceanic spaces around the globe, in terms of the United Nations Convention on the Law of the Sea (UNCLOS). Because of such modifications, this study contextualizes the history of Brazilian territorial sea in 1970 and its political implications, on the national as well as on the international level. After that, it examines the alliances Brazil has formed, engaging in a so called “diplomatic battle”. This process went on for over nine years, comprised more than 130 countries and originated one of the most successful treaties in history: the United Nations Convention on the Law of the Sea. Since then, the signatory states managed to secure their legal rights over the maritime soil and subsoil by means of submissions for the continental shelf beyond 200 nautical miles, as defined by the Convention in its article 76. This achievement was of utmost importance because it enabled developing countries and small island states to access valuable natural resources such as oil, gas and minerals. Every coastal state who has signed the Convention acquired the right to claim its underwater territory or extended continental shelf up to 350 nautical miles from its coast. Due to the new regulations, the Commission on the Limits of the Continental Shelf (CLCS) began to undertake the analysis of submissions. This Commission is a body set up by the UNCLOS, in which experts, selected according to the criterion of geographic equity will accept, modify or reject claims. Furthermore, this study aims to account for procedures taken by coastal, insular, and archipelagic states when claiming the extension of its oceanic limits, with the main focus on measures taken by Brazil. More specifically, it intends to explain how Brazilian experts have brought about the expansion of the extended continental shelf and in which way planning and management, in political terms, can be carried out through the Interministerial Commission for Maritime Resources. Ultimately, it will be examined if the Brazilian government is able to assume such responsibility in the face of the growth of its borders and the capability of the state, in scientific, technological and political terms, of incorporating and enforcing the precepts of the Convention in its national policy for the seas.

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Mahfouf, Jean-François. « Contribution a la definition d'une parametrisation des transferts entre le sol, la vegetation et l'atmosphere : analyse de sensibilite et insertion dans un modele mesoechelle ». Clermont-Ferrand 2, 1986. http://www.theses.fr/1986CLF21010.

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Un modele numerique a mesoechelle (nickerson et al, 1986) comportant un ensemble detaille de parametrisations pour la couche limite planetaire (therry et lacarrere, 1983), la vegetation (deardorff, 1978) et les transferts thermo-hydriques dans le sol (mclumber et pielke, 1981) a ete developpe. Tout d'abord, une version unidimensionnelle nous a permis de realiser un ensemble complet de tests de sensibilite sur l'influence de l'evolution diurne de la basse atmosphere vis a vis de l'etat hydrique du sol, de l'albedo de surface et du type de couvert vegetal notamment. Une comparaison a ete effectuee avec les donnees de l'experience de couche limite "wangara", indiquant un bon accord entre les resultats du modele et l'observation

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Matušíková, Anna. « Navrhování konstrukcí s FRP výztuží ». Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225478.

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This diploma thesis presents available FRP software for calculating load bearing capacity of the structures reinforced with FRP and compares them between each other. Furthermore theory and algorithm of my own software is presented here. Load bearing capacity of structures which are reinforced with non-metallic reinforcement and loaded by combination of normal force and bending moment can be solved by my programme. Effects of high temperatures on the concrete structures can be included in the calculation. In the second part of the thesis is calculated load-bearing capacity and deflection of the real beam reinforced with FRP reinforcement and load-bearing capacity of member with FRP reinforcement with effect of elevated temperature. This has been done using my software. Comparison of results from hand calculation and laboratory load-bearing testing is done at the end. This laboratory testing was accomplished by Institute of Concrete and Mansory Structures at our faculty.

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Clairac, Bernard. « L'aerosol en foret tropicale humide d'afrique : application a l'etude des echanges entre la foret et son environnement ». Toulouse 3, 1986. http://www.theses.fr/1986TOU30144.

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Les mesures ont ete faites, pres du sol, dans une region accidentee (4**(o)s-1**(o)e) de 1978 a 1984. L'aerosol est surtout constitue de composes du carbone, et sa distribution dimensionnelle est formee de 3 modes dont le plus important est centre vers 0,1 micron. Les variations et la composante submicronique sont interpretees en termes de formation et d'evolution des particules et de melanges dans l'atmosphere. Les plus petits noyaux sont formes a partir de gaz emis par la biosphere, principalement au cours de reactions photochimiques. Pendant les heures ensoleillees, la production totale est estimee a 1,8. 10**(5) cm**(-2). S**(-1). 70% des particules formees restent alors dans les vallees, mais sous le couvert forestier la production est faible, et les concentrations augmentent, en fin d'apres-midi, lorsque les melanges amenent les particules formees, le jour, en altitude

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Díaz, Espinosa Oliver Rodolfo. « Renormalization and central limit theorem for critical dynamical systems with weak external random noise ». Thesis, 2006. http://hdl.handle.net/2152/2715.

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Wong, Michael. « Molecular Weight Limit Identified for the Synthesis of Externally Initiated Poly(3-hexylthiophenes) and Further Macrocyclic Constructions ». Thesis, 2013. http://hdl.handle.net/1807/35147.

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Externally initiated o-tolyl initiated poly(3-hexylthiophene) (P3HT) was synthesized according to Grignard metathesis polymerization at varying chain length to compare number average molecular weights (Mn) obtained by gel permeation chromatography (GPC) and 1H NMR end group analysis. The extent of overestimation by GPC (1.3) was determined to be lower than previously reported for low Mn polymers. However, an apparent GPC quantification limit was observed as NMR Mn correlated well to predicted results. Static light scattering studies on high Mn polymers provided evidence that the true molecular weight was more similar to GPC-derived Mn. Despite nearly 100% external initiation efficiency, at a certain Mn limit new uninitiated chains may be synthesized. It is suggested that the synthesis of externally initiated P3HT should be limited to Mn below 40 kDa to ensure fully externally initiated chains. A proposal for the synthesis of externally initiated macrocyclic P3HT will also be discussed.

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GEYER, Anne. « Hybrid outsourcing and liability according to German and English law : external liability of constructions resulting from a transfer of data processing functions beyond the limits of a corporate group ». Doctoral thesis, 1993. http://hdl.handle.net/1814/5553.

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Vamadevan, Varatharajan. « Organization of Glucan Chains in Starch Granules as Revealed by Hydrothermal Treatment ». Thesis, 2013. http://hdl.handle.net/10214/7240.

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Regular starches contain two principal types of glucan polymers: amylopectin and amylose. The structure of amylopectin is characterized according to the unit chain length profile and the nature of the branching pattern, which determine the alignment of glucan chains during biosynthesis. The organization of glucan chains in amylopectin and their impact on the structure of starch are still open to debate. The location of amylose and its exact contribution to the assembly of crystalline lamellae in regular and high-amylose starch granules also remain unknown. The primary focus of this thesis is the organization and flexibility of glucan chains in crystalline lamellae. The organization and flexibility of glucan chains in native, annealed (ANN), and heat-moisture treated (HMT) normal, waxy, hylon V, hylon VII, and hylon VIII corn starches were examined. This study has shown for the first time that increased amounts of apparent amylose in B-type starches hinder the polymorphic transition (from B to A+B) during HMT. The research has also demonstrated that an iodine-glucan complex transformed the B-type polymorphic pattern of hylon starches into a V-type pattern. The differential scanning calorimetry (DSC) results showed that ANN- and HMT-induced changes were most pronounced in hylon starches. These findings suggest that the glucan tie chains influences the assembly of crystalline lamellae in high-amylose starches. The relationship between the internal unit chain composition of amylopectin, and the thermal properties and annealing of starches from four different structural types of amylopectin was investigated by DSC. The onset gelatinization temperature (To) correlated negatively with the number of building blocks in clusters (NBbl) and positively with the inter-block chain length (IB-CL). The enthalpy of gelatinization (∆H) correlated positively with the external chain length of amylopectin. Annealing results showed that starches with a short IB-CL were most susceptible to ANN, as evidenced by a greater increase in the To and Tm. The increase in enthalpy was greater in starches with long external chains and IB-CLs. These data suggest that the internal organization of glucan chains in amylopectin determines the alignment of chains within the crystalline lamellae and thereby the thermal properties and annealing of the starch granules.

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