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Houdoux, David. "Étude expérimentale du lien entre réarrangements locaux et friction interne dans un matériau amorphe modèle". Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S066.
Pełny tekst źródłaWhen a homogeneous stress is applied on a granular material, it first, shows a homogeneous strain and then, above a certain threshold, a heterogeneous strain. However, underlying plasticity mechanisms which trigger this behavior are not known very well. The aim of this thesis is to study how the plasticity organizes in order to understand the transition between a homogeneous strain towards a heterogeneous one. Experiments are carried out on a model amorphous medium consisting of an assembly of glass beads with an average diameter about one hundred microns. A biaxial compressive test in plan strain conditions is performed on the granular material and the organization of the plasticity is observed using the Diffusing Wave Spectroscopy (DWS) technique. During a unixial compression experiment, the plastic field can be decomposed in two components operating on two decoupled strain increment scales. The orientations of these two structures are determined quantitatively. As a result, we observe a slowly varying and coarse-grained part which concentrates along a macroscopic direction corresponding to the Mohr-Coulomb angle; and a fluctuating part that may be related to an Eshelby-like stress redistribution after a plastic rearrangement in an amorphous material. Otherwise, for the first time, we observe and characterize plastic events within shear bands. A qualitative analogy with earth seismicity is deduced
Choi, Won Jong. "Variation de structure du polycarbonate vitreux pendant l'essai de traction observe par mesure du module d'young et du frottement interne". Poitiers, 1986. http://www.theses.fr/1986POIT2280.
Pełny tekst źródłaNguyen, Quoc Lan. "Instabilités liées au frottement des solides élastiques : modélisation de l'initiation des séismes". Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10016.
Pełny tekst źródłaSaïdi, Lamir. "Commande à modèle interne : inversion et équivalence structurelle". Chambéry, 1996. http://www.theses.fr/1996CHAMS024.
Pełny tekst źródłaLucas, Cyrille. "Étude du modèle de l'agrégation limitée par diffusion interne". Thesis, Paris 10, 2011. http://www.theses.fr/2011PA100173/document.
Pełny tekst źródłaThis thesis contains four works on the Internal Diffusion Limited Aggregation model (iDLA), which is a growth model that recursively builds random sets. The first work is set in dimension 1 and studies the case where the random walks that build the aggregate evolve in a random environment. The normalised aggregate then does not converges towards a deterministic limiting shape as it is the case for simple random walks, but converges in law towards a segment that contains the origin and which extremal points follow the Arcsine law. In the second work, we consider the case where the aggregate is built by simple random walks in dimension d > 1. We give convergence and fluctuation results on the odometer function introduced by Levine and Peres, which counts at each point the number of visits of walkers throughout the construction of the aggregate. In the third work, we examine the case where the aggregate is built using multidimensional drifted random walks. We show that under a suitable normalisation, the aggregate converges towards a limiting shape which is identified as a true heat ball. We thus give an answer to an open question in analysis concerning the existence of such a bounded shape. The last work deals with the special case where an interior bound is known for the aggregate. We give a set of conditions on the graph and on the nature of this interior bound that are sufficient to imply an outer bound. This result is applied to the case of random walks on the supercritical bond percolation cluster, thus completing a result by Shellef
Diop, Sette. "Théorie de l'élimination et principe du modèle interne en automatique". Paris 11, 1989. http://www.theses.fr/1989PA112209.
Pełny tekst źródłaThis report is concerned with two problems of control theory: elimination and internal model principle. Elimination consists of transforming a system representation with latent variable into another representation which no longer has a latent variable but which is equivalent to the previous representation, i. E. Which is of the same system. This question has been discussed at length in the literature concerned with constant linear systems by authors such as J. C. Willems, H. Blomberg and R. Ylinen, H. H. Rosenbrock, etc. We show that the differential algebraic elimination theory provides an almost complete solution to the problem for systems which can be described by differential algebraic equations with constant or non-constant coefficients in a differential field of characteristic zero. After dealing with the above question, we note that elimination theory is a key-tool which may serve to solve other control theory problems, since the basic problem is to eliminate an arbitrary variable in a system of equations. This is especially the link with the internal model principle. The latter is initially concerned with the standard regulator problem. It states a necessary structure property of any compensator designed to regulate a system under some regulation condition invoking reference and disturbance signals, called exogenous variables. Roughly, we may say that any compensator which satisfies a regulation condition must be such that the compensated system contains a copy of the exogenous variable model (the exact statement is given). This question has been addressed by E. J. Davison, W. M. Wonham et al. Our method and results improve on this theory. The main result can be reduced to a test which can be made by means of the previous elimination procedure
Peignès, François. "Commande multivariable à modèle interne d'un avant-corps électrique verrier". Paris 11, 1988. http://www.theses.fr/1988PA112067.
Pełny tekst źródłaBlondel, Pierre. "Estimation de l’état interne d’une batterie lithium-ion à l’aide d’un modèle électrochimique". Thesis, Université de Lorraine, 2019. http://www.theses.fr/2019LORR0008/document.
Pełny tekst źródłaDeveloped in the nineties, lithium batteries have colonized our environment in less than thirty years and they keep spreading faster and faster. Powerful, efficient, light and compact, this technology remains hazardous. In order to limit the danger and slow the aging of lithium cells, most of such batteries embed a management system. The latter needs to access some internal states, which are not directly measurable. This thesis intends to estimate these variables using a nonlinear observer, which is based on an electrochemical model. The behavior of the battery is driven by the transportation phenomenon of its main electrochemical species. We therefore built a finite dimensional electrochemical model of these adapted to estimation. It relies on the spatial discretization of the partial differential equations, which describe these transportation phenomena. It also formulates some assumptions, such as the fact that an electrode globally behaves like a single particle of its active material. The obtained state space model has affine dynamics and a nonlinear output. Among the existing observers for such systems that we are aware of, none can be applied directly to the developed model. Hence, we developed new ones whose stability is guaranteed provided a linear matrix inequality holds, which is used to construct the observation gain. We then confront these observers to experimental data acquired on commercialized batteries. The obtained results are encouraging and the observer seems to be a fair compromise between physical meaning and numerical complexity
Boimond, Jean-Louis. "Commande à modèle interne en représentation d'état. : Problèmes de synthèse d'algorithme de commande". Lyon, INSA, 1990. http://www.theses.fr/1990ISAL0102.
Pełny tekst źródła[The works presented in this thesis concern the Internal Model Control (I. M. C. ). The first part presents the main properties of this structure which combines the advantages of open-loop scheme (the controller is an approximate inverse of the model) and closed-loop structure (ability to cope with modelling errors and unmeasured disturbances). A comparison with the conventional closed-loop is briefly presented. In the second part, an asymptotic precision criterion is introduced; The conditions that are to be verified by the blocks of the I. M. C. , for zeroing the asymptotic error between the output and a polynomial input, are settled down. The controller is interpreted as an approximate inverse of the model. In discrete time, the use of F. I. R. (Finite Impulse Response) forms permits the synthesis of a stable and realisable controller. The third part deals with the problem of the model inversion in discrete time and in state space. It allows us to consider some vary linear or non-linear models, which are linear versus the control variable. The controller is decomposed in two parts: the first one generates the control variable in terms of model state and the reference objective, the second one generates the prediction of the reference signal. Asymptotic accuracy is guaranteed for reference inputs that are polynomial, with a given order, versus time. The last part presents the synthesis of an I. M. C. Based on the use of the above controller. The robustness filter becomes a predictor of the error between plant and model outputs, the dynamic of which is tuned according to the knowledge of the plant-model mismatch. Two approaches have been proposed to built in this filter. The first one uses the same technique as for the reference predictor. In the other, the usual notion of filtering is replaced by a measure of the prediction quality. ]
Etcheverry, Patrick. "Sapic : Modélisation et spécification de la coordination interne aux processus d'activités". Pau, 2002. http://www.theses.fr/2002PAUU1014.
Pełny tekst źródłaThis thesis focuses on the specification of coordination within activity-based processes. The aim of this work is to provide the means to understand and describe a coordination system. We elaborate a process model, a coordination model and a computerised system (SAPIC). The process model provides elements that structure the context where coordination is carried out. The coordination model provides elements that allow coordination to be described. SAPIC assists the actors of an activity-based process in specifying its internal coordination. Then, we elaborate coordination patterns describing typical solutions for recurrent situations that need coordination. Finally, we test our models by the means of an audit activity, carried out in a company, in order to analyse and to improve coordination within an inventory control process
Dos, Santos Martins Valérie. "Contrôle frontière par modèle interne de systèmes hyperboliques : application à la régulation de canaux d'irrigation". Phd thesis, Université d'Orléans, 2004. http://tel.archives-ouvertes.fr/tel-00011627.
Pełny tekst źródłaLe modèle utilisé est une linéarisation autour d'un écoulement permanent dont les coefficients dépendent de la variable d'espace. Les pentes et frottements sont non nuls, prenant en compte les phénomènes variables le long du canal.
L'analyse et la synthèse du contrôle sont réalisées en considérant le système en boucle fermée comme une perturbation de celui en boucle ouverte. Les perturbations portent sur les opérateurs, les semigroupes et le spectre dans un espace de Hilbert. L'opérateur hyperbolique Ae(x)dx+ Be(x) est caractérisé explicitement sans transformation préalable, en dimension une d'espace, où Ae(x) et Be(x) sont bornés.
Pour la synthèse de commande, une structure de contrôle frontière par modèle interne est utilisée, après avoir été ramené sous forme Kalmanienne abstraite. L'analyse de la stabilité en boucle fermée, par la théorie de la perturbation en dimension infinie, permet de donner des conditions suffisantes sur les paramètres de synthèse d'une loi de commande du type intégral et/ou proportionnel.
Les résultats en simulation et expérimentaux sur le canal de Valence montrent la faisabilité de l'approche. Elle est testée dans le cas monobief et multibiefs.
Nuglisch, Hans-Joachim. "Étude expérimentale d'un jet axisymétrique compressé : situation modèle de l'aérodynamique interne des moteurs à pistons". Toulouse, INPT, 1992. http://www.theses.fr/1992INPT101H.
Pełny tekst źródłaCharpiot, Anne. "Développement et validation d’un modèle tridimensionnel par éléments finis d’un canal semi-circulaire de l’oreille interne humaine". Strasbourg, 2010. http://www.theses.fr/2010STRA6248.
Pełny tekst źródłaThis thesis exposes the development of a finite element model of one of the accelerometers of the human inner ear (a semicircular canal). The simulations of normal and pathological conditions will find clinical applications to the study and treatment of vertigo. The first step of this research is the development and validation of a 3D finite element model of one semicircular canal: -The mesh totalises 18882 elements, with linear elastic solids and viscous fluid, using ALE fluid/structure coupling. -The validation test is a physiological rotation with short stop, acceleration of 1800°. S-2 during 0. 1 second. The maximal calculated displacement of the cupula is of 17 µm (expected value : 21µm), the relaxation of the cupula needs 5. 2 seconds (expected: 15 seconds). -A parametric study has concerned the membranes and cupula parameters. The first results show that the elasticity of the membranous canal has to be taken in count. The cupula presents a transversal and a longitudinal displacement. This longitudinal displacement had previously been described in static conditions (during hydrops: inflation of the endolymphatic pressure), but had never been considered before in dynamic conditions. The “normal” model that has been developed will further be used to simulate different pathological situations of vertigo (otoconia blocked in the canal, plugged canal in Menière disease, etc. )
Friot, Laurent. "Méthodologie de mise en oeuvre d'une régulation de climatisation par modèle interne appliquée au transport ferroviaire". Poitiers, 1995. http://www.theses.fr/1995POIT2355.
Pełny tekst źródłaCheynet, de Beaupré Aline. "Le modèle dans le droit de la famille : notion et fonction (essai de droit comparé interne)". Paris 2, 1994. http://www.theses.fr/1994PA020130.
Pełny tekst źródłaThe reforms of the french family law beginning in 1964 revealed a certain diversity. For various situations, legislator created various solutions in law. An institution is the model of another that will borrow part of its system. Looking at the model and its borrowing, we discovered that this legislative technic realised law economy by reproducing rules that existed before. Even if two institutions are different according to their legal nature, they can share a quite similar system. The logical of that construction comes from abstracts like: couple, home, food (in its legal acception). . . The whole system appears organised
Gado, Moubarak. "Modèle par éléments discrets multi physique du comportement des matériaux métalliques sous sollicitations thermo mécaniques extrêmes". Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0707/document.
Pełny tekst źródłaThe work of this thesis concerns the development of a model using the discrete element method, for the thermo-mechanical behavior of an aluminum alloy and its microstructural evolution when exposed to conditions of large deformations and/or high deformation rates (Friction StirWelding or FSW). Friction stir welding is a recent welding process invented in 1991 by "The welding Institute" (TWI). This process is different from the others by its ability to weld material in the viscous state, without reaching the melting point. The principle is relatively simple and similar to a milling process except that the cutting tool is replaced by a rotary tool composed of a pin and a shoulder. This process is of great interest in the aircraft industry because it offers the possibility to weld aluminum alloys 2XXX and 7XXX series, known to be difficult to weld by other processes. Since friction stir welding is a recent process, it still remains a subject of active research, to better understand certain issues such as material flow, influence of process parameters (rotation speed, tool shape, ...) and the modification of the microstructure. This last point is particularly important for structural hardening alloys such as those of the 2XXX and 7XXX series. For these aluminum alloys, the mechanical properties are highly dependent on their state of precipitation, which is itself influenced by the heat generated during thewelding. The optimization ofwelding parameters in order to obtain good mechanical properties requires the prediction of precipitation state along thewelded joint. Thework of this thesis is to develop required models at the scale of microstructure allowing to predict the modification of material properties related to the process parameters
Julió, Guifré. "Modélisation dynamique d'une transmission à variation continue (CVT) à courroie de caoutchouc". Mémoire, Université de Sherbrooke, 2010. http://savoirs.usherbrooke.ca/handle/11143/1579.
Pełny tekst źródłaAvoine, Jérôme. "Analyse expérimentale et modélisation de couplages multiphysiques dans un contact frottant / acier-matériau de friction modèle". Ecole Centrale de Lille, 2007. http://www.theses.fr/2007ECLI0015.
Pełny tekst źródłaCette étude concerne le freinage par friction et tout particulièrement les couplages entre les différents aspects physiques activés à des échelles différentes. Un accent particulier est porté sur la structuration des résultats d’essais par une approche globale, avec utilisation de l’outil numérique comme moyen de justification des hypothèses avancées. Après avoir posé la problématique du freinage au niveau scientifique en s’appuyant sur les aspects multi-physiques et multi-échelles, les outils expérimentaux et numériques utilisés sont présentés. Un matériau de friction modèle, de composition simplifiée, a été développé. Sa caractérisation a été entreprise en s’attachant à la mise en place d’indicateurs permettant de remonter aux températures locales de contact en freinage. Plusieurs campagnes d’essais de freinage de maintien ont été conduites sur un tribomètre instrumenté en particulier avec une caméra infrarouge et des accéléromètres. Les résultats ont été analysés finement en dégageant les couplages entre les phénomènes tribologiques, thermiques, mécaniques et physico-chimiques. Un ensemble d’organigrammes a été construit afin d’illustrer ces couplages. Il est montré en particulier que le couplage thermique-mécanique est prépondérant et qu’il évolue fortement avec le vieillissement du matériau permettant à d’autres couplages liés à la tribologie et à la dynamique de s’intensifier. Ceci ouvre de nombreuses perspectives académiques, grâce à la compréhension des mécanismes mis en jeu, et industrielles, par une démarche structurée de développement de matériaux de friction
Karfoul, Hazem. "L'efficacité du système de contrôle interne et le seuil optimal du risque opérationnel : un modèle d'équilibre de l'allocation des ressources pour l'organisation bancaire". Bordeaux 4, 2010. http://www.theses.fr/2010BOR40089.
Pełny tekst źródłaOperational risk measurement models, aiming to meet regulatory capital requirements (ORC), have seen a great proliferation lately. Nonetheless, accounting for the effectiveness of internal control system (ICS) in these models is still carried out in an implicit manner. Such failure may lead to biased estimations of ORC which are inconsistent with the effective operational risk profile of the bank. In this work, we endeavor to overcome this pitfall through a direct and explicit measure of the internal control system’s quality. Our findings show that ORC is negatively related to ICS. However, each bank has a given threshold beyond which his operational risk capital does not respond to additional improvements brought into his ICS (i. E. , optimal threshold for operational risk, OTOR). We argue that, the so-called “law of decreasing effectiveness” seems explain well the theorem of OTOR. Taking into account the information asymmetry problems, arguably hard to be verified by banking supervisors, we provide as well an equilibrium model for resources allocation subject to regulatory constraints and management preferences. The introduction of OTOR, as an optimization problem, will affect the bank’s decision about how the scarce resources should be allocated. Accordingly, sharing out the resources becomes more efficient. While reducing the ORC charge, the bank’s management can shift more resources to be invested in higher return-generating activities, keeping up, meantime, in compliance with regulatory requirements. Furthermore, by means of OTOR, a simple formula for pricing the “operational risk premium” is provided
Hillion, Mathieu. "Contrôle de combustion en transitoires des moteurs à combustion interne". Phd thesis, École Nationale Supérieure des Mines de Paris, 2009. http://pastel.archives-ouvertes.fr/pastel-00005749.
Pełny tekst źródłaJacoby, Nadia. "L'influence des processus de sélection interne sur les performances des firmes : un modèle évolutionniste de micro-simulation". Paris 1, 2002. http://www.theses.fr/2002PA010063.
Pełny tekst źródłaRichard, Adrien. "Modèle formel pour les réseaux de régulation génétique et influence des circuits de rétroaction". Evry-Val d'Essonne, 2006. http://www.biblio.univ-evry.fr/theses/2006/Interne/2006EVRY0048.pdf.
Pełny tekst źródłaIn this thesis, we propose a general discrete model for genetic regulatory network. The structure of a network is described by a signed directed graph which indicates the activations / inhibitions present between genes and the dynamics is represented by an asynchronous transition system. Then, we search dynamical properties which can be deduced from the interaction graph. Principally, we prove discrete versions of the Thomas’s conjectures. We thus prove that the presence of a positive (resp. Negative) circuit in the interaction graph of a network is necessary for the presence of several attractors (reps. Stable cycles) in the dynamics of the network. Finally, we propose a method allowing the automatic selection of the dynamics associated to a given interaction graph which verify experimental observations. For that, we use model cheking techniques
Salah-Mohellibi, Nouzha. "La transplantation de moelle osseuse atténue le phénomène musculaire d'un modèle murin d'amyotrophie spinale". Evry-Val d'Essonne, 2006. http://www.biblio.univ-evry.fr/theses/2006/Interne/2006EVRY0038.pdf.
Pełny tekst źródłaSMA ("spinal muscular atrophy") is an autosomal recessive disorder affecting 1 in 10000 newborns. SMA is characterized by the degeneration of the anterior horn cells of the spinal cord associated with a proximal muscle paralysis. Mutations of the survival motor neuron (SMN1) gene are responsible for SMA. These data led us to investigate therapeutic strategies targeting both neurons and skeletal muscle. Our goal was to test the therapeutic potentialities of bone marrow-derived cells by using transplantation of wild-type bone marrow cells following irradiation of 2 month-old recipient mice. This experiment improved their motor capacity and led to an activation of skeletal muscle regeneration. We also showed that HGF transcripts and protein were upregulated in the skeletal muscle of mutant mice transplanted with wild-type bone marrow. These data indicate that HGF may represent a good candidate factor to ensure this biological activity
Marc, Daniel. "Étude expérimentale de la compression d'un écoulement de rouleau : situation modèle de l'aérodynamique interne des moteurs à pistons". Toulouse, INPT, 1998. http://www.theses.fr/1998INPT013H.
Pełny tekst źródłaIbanez-Pascual, Stéphanie. "Conception d'un modèle équilibré de performance : des leviers innovants en matière de management des hommes". Phd thesis, Paris, ENSAM, 2008. http://pastel.archives-ouvertes.fr/pastel-00004321.
Pełny tekst źródłaAubert, Anne. "Effet de la trimétazidine dans les processus ischémiques de l'oreille interne. Etude électrophysiologique sur le modèle du canal semi-circulaire isolé de grenouille". Rouen, 1990. http://www.theses.fr/1990ROUES013.
Pełny tekst źródłaD'Alvise, Laurent. "Développement d'un modèle éléments-finis pour la simulation du procédé de soudage par friction inertielle entre matériaux dissimilaires". Paris, ENMP, 2002. http://www.theses.fr/2002ENMP1108.
Pełny tekst źródłaLèbre, Sophie. "Analyse de processus stochastiques pour la génomique : étude du modèle MTD et inférence de réseaux bayésiens dynamiques". Evry-Val d'Essonne, 2007. http://www.biblio.univ-evry.fr/theses/2007/interne/2007EVRY0017.pdf.
Pełny tekst źródłaThis thesis deals with DNA sequence and time series gene expression analysis. First we study the parsimonious Markov model called Mixture Transition Distribution (MTD) model and introduce an EM algorithm for MTD models estimation. Then we propose two approaches for genetic network recovering using Dynamic Bayesian Networks (DBNs). The dependencies are described by a directed graph whose topology has to be inferred despite the overly low number of repeated measurements compared with the number of observed genes. First we assume that the topology is constant across time, we approximate this graph by considering partial order dependencies and we develop a deterministic procedure for DBNs inference. Then we consider a multiple changepoint regression model defining a succession of homogeneous phases. The changepoints location and the structure within each phase are simultaneously inferred thanks to a reversible jump MCMC procedure
Hainque, Elodie. "Transition de poursuite oculaire chez l'homme : vers une compréhension de la constitution d'un modèle interne d'un <>". Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066332.
Pełny tekst źródłaTwo types of eye movements are combined while tracking a moving object: smooth pursuit and saccades. Saccades are rapid redirections of the visual axis between two centers of interest. Because pursuit gain is smaller than one, the eye would increasingly lag behind the target without any correcting movements. Thus, “catch-up saccades” are triggered by the central nervous system (CNS) to cancel this growing position error between the eye and the target. It is widely accepted that an internal model of target motion is used by the CNS to cancel inherent delays between visual input and smooth pursuit motor output, ensuring accurate tracking of moving targets. The amplitude of catch-up saccades triggered during smooth pursuit could be corrected by a delayed sensory signal to account for the ongoing target displacement during catch-up saccades. Yet, recent studies suggested that the correction of catch-up saccade amplitude must also be done through an internal model of target motion. We developed a new paradigm in which the target switches unexpectedly from one target with a non-constant periodic velocity profile to another with a non-constant aperiodic velocity profile. Our results in healthy humans confirm that the CNS uses an internal model of target motion to correct catch-up saccade amplitude. Internal model is being built gradually from 168 ms after the target switch. We show that a common internal model of target motion is shared within the CNS to control smooth pursuit and to correct catch-up saccade amplitude. The potential neuronal substrate of such an internal model will be discussed in the light of the knowledge from the literature on motor and oculomotor control
Ekwe, Georges Fidèle. "Modélisation et simulation numérique pour le diagnotic des machines électriques : une approche par le modèle interne à circuits équivalents". Amiens, 2004. http://www.theses.fr/2003AMIE0315.
Pełny tekst źródłaGuilbert-Lepoutre, Aurélie. "Propriétés de surface et structure interne des objets Trans-Neptuniens et des Centaures : un nouveau modèle d'évolution thermique 3D". Paris 7, 2009. http://www.theses.fr/2009PA077246.
Pełny tekst źródłaSmall Icy bodies of the Solar System are mainly constituted by Transneptunian Objects and Centaurs. These two populations are composed of numerous bodies, whose dynamical, physical and chemical properties can be very different. Their observations have remained challenging until recently. Thus, the study of the Transneptunian région is a research field in rapid and constant evolution. TNOs and Centaurs should be composed of varions ices. At the very beginning of this thesis, an ESO Large Program has been undertaken, in order to constrain thé surface composition of a significant sample of bodies. I was in charge of the H+K spectra obtained with the new instrument SINFONI. I therefore had to establish an optimized observation technique and a performant data reduction procedure, for which each step has been widely tested. Each spectrum has been analyzed individually, and a radiative transfer model has been applied to determine the surface composition of each object. Absorption bands attributed to water ice and other volatil ices have been detected. The presence of some volatil ices on these objects' surfaces raises questions about the possible internal activity they can undergo. I consequently developed a three-dimensional thermal model, using a mathematical solution limiting the computation time. This new internal evolution model allows to compute lateral beat fluxes and 3D boundary conditions, without any excessive computation time. I tested the influence of the most critical parameters such as the formation time of the objects, the matrix thermal conductivity, etc. The main results throw new leads for the observations interpretation. Finally, I managed to draw a portrait of Centaur 10199 Chariklo: the data obtained in the framework of the Large Program show indeed important variations compared to the previously published ones. Several hypothesis are considered to explain these changes: spatial variations, temporal variations, or cometary outbursts. Observational data alone do not allow to discard any of those three explanations. I therefore applied the 3D thermal model which allows to exclude some temporal variations
Crétat, Julien. "Pluviométrie et circulation atmosphérique simulées par le modèle régional WRF en Afrique australe : sensibilité à la physique et variabilité interne". Phd thesis, Université de Bourgogne, 2011. http://tel.archives-ouvertes.fr/tel-00721870.
Pełny tekst źródłaGrousson, Frédéric. "Définition et mise en oeuvre de lois de commande à modèle interne pour un moteur thermique à injection directe d'essence". Toulouse, INPT, 2000. http://www.theses.fr/2000INPT056H.
Pełny tekst źródłaThis study has been achieved in order to improve the direct injection engine control, by using internal model control strategies. Its aim is to optimise the engine performance and to decrease the polluting emissions through a better dynamic control. The use of internal model controls brings robustness in order to face the engine parameter disparity and allows great improvements in the control calibration thanks to a shorter tuning time. The first part gives the outlines of thermic engine operating and focuses on modelization with the final control in view. The second part tackles the implementation of regulation algorithms. Firstly,the air path control uses the state feedback linearization mixed with the predictive control. Secondly, the torque control of the driver's requests is performed with a static inversion using the Jacobian matrix. Finally, a simplified predictive control makes it possible to solve idle speed regulation problems. The last part is devoted to real time and fast prototyping tests. The main simulation results have been validated through experimental tests on a direct injection car
Nugroho, Dwiyoga. "La marée dans un modèle de circulation générale dans les mers indonésiennes". Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30089/document.
Pełny tekst źródłaIn the Indonesian seas, large tidal currents interact with the rough topography and create strong internal waves at the tidal frequency, called internal tides. Part of them will eventually propagate and dissipate far away from generation sites. Their associated mixing upwells cold and nutrient-rich water that prove to be critical for climate system and for marine resources. This thesis uses the physical ocean general circulation model, NEMO, as part of the INDESO project that aims at monitoring the Indonesian marine living resources. Models not taking into account tidal missing are unable to correctly reproduce the vertical structure of watermasses in Indonesian seas. However, taking into account this mixing is no simple task as the phenomena involved in tidal mixing cover a wide spectrum of spatial scales. Internal tides indeed propagate over thousands of kilometres while dissipation and mixing occurs at centimetric to millimetric scales. A model capable of resolving all these processes at the same time does not exist. Until now scientists either parameterised the tidal mixing or used models which only partly resolve internal tides. More and more scientists introduce explicit tidal forcing in their models but without knowing where the energy is going and how the internal tides are dissipated. This thesis intends to quantify energy dissipation in NEMO forced with explicit tidal forcing and compares it to the dissipation induced by the currently used parameterization. This thesis also provides new results about the quantification of the tidal energy budget in NEMO. I first contributed to an INDESO study that aimed at validating the model against several observation data sets. In a second and third study, I investigated the mixing produced in the model by explicit tidal forcing and its impact on water mass. Explicit tides forcing proves to produce a mixing comparable to the one produced by the parameterization. It also produces a significant cooling of 0.3 °C with maxima reaching 0.8°C in the areas of internal tide generation. The cooling is stronger on austral winter. The spring tides and neap tides modulate this impact by 0.1°C to 0.3°C. The model generates 75% of the expected internal tides energy, in good agreement with other previous studies. In the ocean interior, most of it is dissipated by horizontal momentum dissipation (19 GW), while in reality one would expect dissipation through vertical possesses. This value is close to the dissipation induced by the parameterization (16 GW). The mixing is strong over generation sites, and only 20% remains for far field dissipation mainly in the Banda and Sulawesi Seas. The model and the recent INDOMIX cruise [Koch-Larrouy et al. (2015)], which provided direct estimates of the mixing, are surprisingly in good agreement mainly above straits. However, in regions far away from the energy generation sites where INDOMIX found NO evidence of intensified mixing, the model produces too strong mixing. The bias comes from the lack of specific set up of internal tides in the model. More work is thus needed to improve the modeled dissipation, which is a theme of active research for the scientific community. I dedicated the last part of my thesis to the quantification of tidal energy sinks in NEMO. I first worked on a simple academic case: the COMODO internal tides test case, which analyses the behaviour of a vertically stratified fluid forced by a barotropic flow interacting over an idealized abyssal plain/slope/shelf topography without bottom friction. The results of the finite element T-UGOm hydrodynamic model are compared with those of NEMO. The central issue in calculating tidal energy budget is the separation of barotropic and baroclinic precesses
Truchot, Benjamin. "Développement et validation d'un modèle eulérien en vue de la simulation des jets de carburants dans les moteurs à combustion interne". Phd thesis, Toulouse, INPT, 2005. http://oatao.univ-toulouse.fr/7465/1/truchot.pdf.
Pełny tekst źródłaThibault, Robert. "Contrôle de l'énergie injectée dans un réseau électrique par un convertisseur triphasé utilisant un régulateur basé sur un modèle interne sinusoïdal". Mémoire, École de technologie supérieure, 2006. http://espace.etsmtl.ca/511/1/THIBAULT_Robert.pdf.
Pełny tekst źródłaFreydier, Perrine. "Dynamique interne au front d'écoulements à surface libre. Application aux laves torrentielles". Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAU010/document.
Pełny tekst źródłaA depth-averaged model based on the thin-layer assumption, called Saint-Venant (Shallow-Water), is classically used to simulate the propagation and the spreading of debris and mud flows. It is based on several approximations concerning the shape of the velocity profile in non-uniform zones. We propose to test these hypotheses, examining a strongly non-uniform zone, the front of free-surface viscoplastic flows and the velocity field within this zone. By improving our knowledge about the internal dynamics in the front zone, we seek to improve the thin-layer models. This thesis therefore focuses on the study of the internal dynamics within the front of viscoplatic free-surface flows.We used the moving conveyor belt to generate stationary flows. We carried out a technical work on this set-up, and specific analysis of images obtained from the high-speed camera, in order to be able to measure velocity fields with a high resolution. The study of a Newtonian fluid was also carried out in order to validate the lubrication model and the experimental device.We compared experimental results to theoretical solutions of two thin-layer models taking into account the Herschel-Bulkley rheology: the classical model of lubrication, which is at the base of Saint-Venant model, and a consistent first-order model specifically developed in this thesis.The first-order model is equal to the zero-order model (lubrication), plus corrective terms derived from the normal stresses and inertia terms.In this study, for the purpose of comparison with our experimental results, we are interested in travelling-wave solutions. We are able to solve the shape of the front without using a depth-averaged model.Far from the front, experimental velocity profiles clearly display the characteristic 2-layer structure predicted by the lubrication solution, with constant values close to the free-surface (plug) and a sheared layer underneath. Closer to surge tip, the shape of experimental longitudinal velocity profilesthen begins to differ from the theoretical prediction. The 2-layer structure tends to disappear, and the profiles display shear across the whole depth ofthe flow. In this tip region, surface velocity also appears to increase faster than its theoretical counterpart. Surface velocity predicted by the first-order model increase more drastically in the tip region, in better agreement with the measurements than the lubrication model. The first-order model predicts a sheared velocity profile when approaching the front, as observed experimentally.The consistent first-order model then provides better predictions about internal dynamics than lubrication model. A depth-integrated model like Saint-Venant, based on consistent first-order developments is then calculated, as a first step before being integrated into an operational simulation tool
Bourniquel, Julien. "Propriétés de transfert d'un contact métallique : application à l'étanchéité interne de robinetterie industrielle". Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0551/document.
Pełny tekst źródłaIn a nuclear power plant from pressurized water reactor technology, the transfer of energy from fission of uranium 235 atom to the alternator producing electricity is performed through different water circuits. The context of this work is the primary circuit of the power plant where there is severe conditions of temperature and pressure (155 bar, 300°C). More precisely, this work is about the industrial valves which allow to regulate or interrupt the water flow in the water circuit or the auxiliary associated circuits. The interruption function is ensured by a metal-to-metal contact.In this work a model is derived and solved in order to relate the sealing leak-rate through the metal contact to a possible defect present on the surface. To accomplish this task, a coupled experimental and numerical approach is adopted. The numerical model allows to compute the contact between the plug and the seat and then the water flow through the remaining aperture field. This is performed by solving the equations of solid continuum mechanics with code_aster and the Reynolds equations with an original scheme based on the boundary element method. The experimental work allows to check the relevance of the model. It consists in the manufacture ofa sample seat holding a controlled defect and then a leak-rate measurement carried out with two different apparatus. Predictions of the leak-rate reveal to be in good agreement with that obtained experimentally at low clamping forces and overestimate the leakage for larger ones
Villoing, Daphnée. "Apport du code Monte-Carlo GATE pour la dosimétrie en radiothérapie interne vectorisée : imagerie et calculs dosimétriques". Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30180/document.
Pełny tekst źródłaIn Targeted Radionuclide Therapy (TRT), assessing the absorbed dose delivered to tumours and healthy tissues participates to the evaluation and optimisation of the therapy. This PhD work investigates the input of Monte Carlo code GATE as a toolkit for applications in internal dosimetry in a context of improvement of dosimetric methods. Within DosiTest project, which aims at evaluating the impact of the various steps contributing to the realization of a dosimetric study by means of a virtual multi-centric inter-comparison based on Monte-Carlo modelling, scintigraphic datasets were generated with GATE for two virtual patients (using XCAT and ICRP 110 models), for two different radiopharmaceuticals (OctreoscanTM and LutatheraTM) following a compartmental modelling of biodistribution. After a validation study of GATE for clinical internal dosimetry applications by a comparison with radiation transport code MCNPX, reference dosimetric calculations were performed with GATE
Guervilly, Céline. "Dynamos numériques planétaires générées par cisaillement en surface ou chauffage interne". Phd thesis, Grenoble, 2010. http://www.theses.fr/2010GRENU024.
Pełny tekst źródłaWe develop a hybrid numerical code based on a quasi-geostrophic model for the flows inside the planetary cores driven by internaI heating. For small Prandtl numbers, large amplitude geostrophic zonaI circulations are a robust feature of these flows. The scale and the amplitude of the zonaI motion are controlled by potential vorticity mixing and boundary friction. We identify the presence of large-scale Rossby waves propagating in the vigourously convecting region. The flows produce kinematic dynamos, with a small-scale poloidal magnetic field and a mainly axisymmetric toroidal field~ We find that the impact of the thermal wind on the dynamo threshold is not significant. Ln the second part of this thesis, we study dynamos generated by surface shears. Spherical Couette flow (between two spheres in differential rotation) produces dynamos with a high critical Reynolds number. By breaking the axial symmetry of the flow, the shear instability (in the form of a wave) plays a crucial role. The toroidal magnetic field is large compared with the poloidal field, suggesting the role of the omega effect. We study the dynamics and the dynamo action produced by zonaI jets, Le. , produced by differential rotation that is alternately westward and eastward. The zonaI jets imposed at the outer surface are modified by Rossby waves, which widen the jets and lower their amplitude. The dynamo mechanism relies on the propagation of the Rossby waves. We can establish a link between production of the axisymmetric poloidal magnetic field and the width of the iets throul!h the lenl!thscale of the Rossbv waves
Guervilly, Céline. "Dynamos numériques planétaires générées par cisaillement en surface ou chauffage interne". Phd thesis, Grenoble, 2010. http://tel.archives-ouvertes.fr/tel-00576177.
Pełny tekst źródłaDebiolles, Alexandra. "Diagnostic de systèmes complexes à base de modèle interne, reconnaissance des formes et fusion d’informations : Application au diagnostic des Circuits de Voie ferroviaires". Compiègne, 2007. http://www.theses.fr/2007COMP1672.
Pełny tekst źródłaThis works presents different diagnosis methods that aim at detecting and estimating defects appearing on a system made up of several spatially related subsystems. The application deals with the diagnosis of track circuits. A first approach based on an internal model is layed out; it allows to detect and assess the graveness of ail the system defects, by optimizing a local physical model of the system. But this method is dependant from the good estimation of several parameters of the model. The second method that is set out is an external approach based on classical pattern recognition. A classifier is associated to each subsystem. Their outputs are combined within the framework of belief functions in order to manage possible conflicts among the classifiers. This method is very efficient, but it can only detect one defect without assessing its graveness. Finally a last approach is presented, that combines the two previous ones in order to both detect several defects, and assess them
Le, Ruyet Anicet. "Comportement de l’abdomen soumis au choc : apport de l’échographie ultra-rapide pour la validation interne des modèles". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1228/document.
Pełny tekst źródłaDuring an automotive accident, the abdomen can be subjected to rapid loading leading to abdominal organ injuries. Although human body models become increasingly prevalent to predict injuries during an impact, the validation of their internal response is difficult, in particular due to the lack of data available. Such impact last less than ten milliseconds making the use of standard imaging (e.g. MRI) tools difficult. Based on a recent imaging modality (ultrafast ultrasound imaging), this work focuses on the study of the internal response of the abdomen during an impact. The in situ internal response of abdominal organs (liver, colon) was observed during impacts delivered to post mortem human surrogates. For the first time, trends were found between the external response and the internal organ kinematics. These tests were simulated using an existing human body model leading to similar trends for some of the responses. Also, a method was developed allowing estimating 2D strains in organs during an impact based on ultrafast ultrasound images. This method was first evaluated numerically and experimentally. Then, it was used to process images of human and porcine kidneys during an impact from a previous study. Results highlight the influence of parameters such as the impact speed on the 2D strains estimated in different organ regions.Overall, this research allowed improving upon the current knowledge on the internal response of the abdomen subjected to impact. It also showed the performance limitation of current human body models. The method developed to compute strain maps should help to further improve that knowledge in the future
Lales, Charles. "Modélisation gros grains et simulation multi-agents - Application à la membrane interne mitochondriale". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2007. http://tel.archives-ouvertes.fr/tel-00452853.
Pełny tekst źródłaDucoux, Maxime. "Structure, thermicité et évolution géodynamique de la Zone Interne Métamorphique des Pyrénées". Thesis, Orléans, 2017. http://www.theses.fr/2017ORLE2026/document.
Pełny tekst źródłaThe understanding of the processes and scenarios of the inversion of extensional systems, and more specifically of hyper-extended margins, in collision thrust belts is a major issue. The intracontinental belt of the Pyrenees is an example of inversion of hyper-extended margins, associated with a HT-LP metamorphism and then integrated within the orogenic wedge. The first part of this study is focused on the distribution of the HT-LP metamorphism associated with rifting and the exhumation of lithospheric mantle. A new set of TRSCM data allows the recognition of the geometry of the IMZ, characterized with temperature ranging from 400 to 630°C and shows the absence of a regional gradient at this scale. This study then shows significant temperature gaps across major faults and distinguishes lateral temperature gradients at the scale of the different basins constituting the IMZ, especially in the westernmost part of the belt, in the Nappe des Marbres Basin. This part of the study moreover shows the importance of a salt tectonics prior to the HT-LP metamorphism. The second part shows the existence of three main tectonics phases during the Pyrenean orogeny and the role played by the Late Triassic evaporites as a decollement level in the generalized allochthony of the IMZ. A left-lateral component along the main faults within and along the boundaries of the North Pyrenean Zone (ZNP) is also shown. The interpretation of these observations is that the IMZ and ZNP form a single tectonic unit, decoupled from the Variscan basement by the decollement in the Late Triassic deposits and displaced above shallow-dipping thrust faults inherited from the rifting episode, during the first stages of the convergence. Deformation mode is then thin-skinned and becomes thick-skinned when the two paleomargins collide, with the development of major steeper faults linked with the exhumation of basement blocks (North Pyrenean Massifs) that dissected the IMZ
Venail, Frédéric. "Transfert d'ADN dans la cochlée de mammifère par vecteur adénoviral : mise au point technique vers un modèle de régénération de l'organe de Corti utilisant l'interférence ARN". Montpellier 1, 2008. http://www.theses.fr/2008MON1T024.
Pełny tekst źródłaMaugain, Géraldine. "La modélisation du procès civil. : émergence d'un schéma procédural en droit interne". Thesis, Dijon, 2010. http://www.theses.fr/2010DIJOD004.
Pełny tekst źródłaThe 20th century has initiated a new dawn for procedure as a tool to defend the rights of the persons subject to trial, a change motivated by a constant care to guarantee the supranational pattern of due process of law. At the end of the century, new stakes focused on more financial aspects also emerged. The efficiency of justice merged with the quality of the judicial decision to create a concept of smooth-running of justice. These common values generated an emerging procedural pattern reflecting the civil justice of the 21st century. At the level of procedural structure, a schism in the contentious stage developed into a strong readiness for trial and a complementary judgment stage. Now, both phases must be preceded by a consensual phase, which is still scarcely used though everyone seeks it. Regarding decision-making, the judge’s role must remain the same, stating the legal position. The main goal is then to give the judge what it takes to fulfil his function through the regression of his minor roles, thus defining more accurately what his original role is
Duffaut, Olivier. "Problématique multi-modèle pour la génération d'arbres de test : application au domaine de l'automobile". Toulouse, ENSAE, 1994. http://www.theses.fr/1994ESAE0005.
Pełny tekst źródłaPagnoux, Geoffrey. "Mise en évidence et simulation de l’endommagement des revêtements de carbone amorphe pour application moteur à combustion interne". Thesis, Paris Est, 2015. http://www.theses.fr/2015PESC1175.
Pełny tekst źródłaThe use of micrometric diamond-like carbon coatings (named DLC) are becoming widely used by automotive manufacturers in order to improve the efficiency of internal combustion engines by reducing the mechanical friction losses. Although DLC coatings generally exhibit excellent tribological properties and very low wear rates, their use in internal combustion engines shows that, subject to complex loadings, many degradation modes are observable. Untimely propagation of these latter upon the entire coated surfaces is a risk to control in order to guarantee the coating function over time. From one hand, this control implies to know and to understand all DLC degradation mechanisms when applied to engine components. On the other hand, it is necessary to possess lifetime simulation tools that can be used to optimize tribological systems in their early design. The work presented in this thesis has been guided by these goals and gathers experimental analyses of DLC-coated components, numerical analyzes, simplified testing protocols and coupling analyses of degradation processes. All these topics finally lead to the definition of a lifetime simulation tool adapted to DLC coated internal combustion engine applications
Kolegain, Komlan. "Correction de trajectoires d'un robot manipulateur utilisé pour le soudage par friction malaxage". Thesis, Paris, ENSAM, 2019. http://www.theses.fr/2019ENAM0033/document.
Pełny tekst źródłaFriction Stir Welding (FSW) is a recent process used for welding metallic parts in aerospace, automotive, and railway industries. Serial industrial robots may be used as FSW welding machines, but because of their lack of stiffness, they undergo elastic deformation under the effect of stresses produced by the process. This causes a welding tool path deviation both in position and orientation, which induces defects in the weld seam. In this work, two path correction methods were developed. The first method is based on the prediction of the position and orientation deviations in the cartesian space from robot models and stiffness model of the links and the joints. The knowledge of tool deviations enabled the synthesis of a path programming approach adapted for robotic FSW. Unlike linear interpolation methods often used, this approach is based on approximations of the adapted path by Bézier or B-splines curves. Experimental validations on a Kuka KR500-2MT robot welding complex paths showed an average residual deviation of 0.3 mm and weld seams without defects. The path accuracy achieved makes it possible to consider an industrial exploitation of the developed solution. The second proposed correction method uses position feedback with a 2D laser profile sensor in the feedback loop for real-time measurement of deviations. Two controllers were designed to correct the deviations. In spite of the external disturbances related to the constraints of the process, experimental results obtained on straight and curvilinear welding paths showed the stability of the feedback loop and a mean residual deviation of 0.1 mm was achieved. The interests and difficulties of deploying this second method were also highlighted