Tesis sobre el tema "Données cinétiques"
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Bauchet, Jean-Philippe. "Structures de données cinétiques pour la modélisation géométrique d’environnements urbains". Thesis, Université Côte d'Azur (ComUE), 2019. http://www.theses.fr/2019AZUR4091.
Texto completoThe geometric modeling of urban objects from physical measurements, and their representation in an accurate, compact and efficient way, is an enduring problem in computer vision and computer graphics. In the literature, the geometric data structures at the interface between physical measurements and output models typically suffer from scalability issues, and fail to partition 2D and 3D bounding domains of complex scenes. In this thesis, we propose a new family of geometric data structures that rely on kinetic frameworks. More precisely, we compute partitions of bounding domains by detecting geometric shapes such as line-segments and planes, and extending these shapes until they collide with each other. This process results in light partitions, containing a low number of polygonal cells. We propose two geometric modeling pipelines, one for the vectorization of regions of interest in images, another for the reconstruction of concise polygonal meshes from point clouds. Both approaches exploit kinetic data structures to decompose efficiently either a 2D image domain or a 3D bounding domain into cells. Then, we extract objects from the partitions by optimizing a binary labelling of cells. Conducted on a wide range of data in terms of contents, complexity, sizes and acquisition characteristics, our experiments demonstrate the scalability and the versatility of our methods. We show the applicative potential of our method by applying our kinetic formulation to the problem of urban modeling from remote sensing data
Yu, Mulin. "Reconstruction et correction de modèles urbains à l'aide de structures de données cinétiques". Thesis, Université Côte d'Azur, 2022. http://www.theses.fr/2022COAZ4077.
Texto completoCompact and accurate digital 3D models of buildings are commonly used by practitioners for the visualization of existing or imaginary environments, the physical simulations or the fabrication of urban objects. Generating such ready-to-use models is however a difficult problem. When created by designers, 3D models usually contain geometric errors whose automatic correction is a scientific challenge. When created from data measurements, typically laser scans or multiview images, the accuracy and complexity of the models produced by existing reconstruction algorithms often do not reach the requirements of the practitioners. In this thesis, I address this problem by proposing two algorithms: one for repairing the geometric errors contained in urban-specific formats of 3D models, and one for reconstructing compact and accurate models from input point clouds generated from laser scanning or multiview stereo imagery. The key component of these algorithms relies upon a space-partitioning data structure able to decompose the space into polyhedral cells in a natural and efficient manner. This data structure is used to both correct geometric errors by reassembling the facets of defect-laden 3D models, and reconstruct concise 3D models from point clouds with a quality that approaches those generated by Computer-Aided-Design interactive tools.My first contribution is an algorithm to repair different types of urban models. Prior work, which traditionally relies on local analysis and heuristic-based geometric operations on mesh data structures, is typically tailored-made for specific 3D formats and urban objects. We propose a more general method to process different types of urban models without tedious parameter tuning. The key idea lies on the construction of a kinetic data structure that decomposes the 3D space into polyhedra by extending the facets of the imperfect input model. Such a data structure allows us to re-build all the relations between the facets in an efficient and robust manner. Once built, the cells of the polyhedral partition are regrouped by semantic classes to reconstruct the corrected output model. I demonstrate the robustness and efficiency of the algorithm on a variety of real-world defect-laden models and show its competitiveness with respect to traditional mesh repairing techniques from both Building Information Modeling (BIM) and Geographic Information Systems (GIS) data.My second contribution is a reconstruction algorithm inspired by the Kinetic Shape Reconstruction method, that improves the later in different ways. In particular, I propose a data fitting technique for detecting planar primitives from unorganized 3D point clouds. Departing from an initial configuration, the technique refines both the continuous plane parameters and the discrete assignment of input points to them by seeking high fidelity, high simplicity and high completeness. The solution is found by an exploration mechanism guided by a multi-objective energy function. The transitions within the large solution space are handled by five geometric operators that create, remove and modify primitives. I demonstrate its potential, not on buildings only, but on a variety of scenes, from organic shapes to man-made objects
Martins, Rogerio. "Modélisation de la réactivité à partir d'une base de données cinétiques de réactions et de descripteurs moléculaires". Aix-Marseille 3, 2002. http://www.theses.fr/2002AIX30020.
Texto completoOur work aims to help prediction and comprehension of reactivity of electrophilic radicals HO·, Cl· and F· with volatile organic compounds starting from structure-reactivity models. These models are validated for a widest range of data. To this end, we have developed a kinetic database of bimolecular reactions in gas phase indexed by structure and a database of molecular descriptors. By exploiting these databases using statistical tools such as the Exploratory Data Analysis, we have obtained predictive models of reactivity and that give elements of explanation to the reactivities of the molecules
Moreau, Anne. "Contribution au contrôle de la culture de Brevibacterium linens en réacteur Batch, modélisation et optimisation des cinétiques de croissance sur substrat mixte". Toulouse, INPT, 2000. http://www.theses.fr/2000INPT001G.
Texto completoBaradat, Aymeric. "Transport optimal incompressible : dépendance aux données et régularisation entropique". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLX016/document.
Texto completoThis thesis focuses on Incompressible Optimal Transport, a minimization problem introduced by Brenier in the late 80's, aiming at describing the evolution of an incompressible and inviscid fluid in a Lagrangian way , i.e. by prescribing the state of the fluid at the initial and final times and by minimizing some functional among the set of admissible dynamics. This text is divided into two parts.In the first part, we study the dependence of this optimization problem with respect to the data. More precisely, we analyse the dependence of the pressure field, the Lagrange multiplier corresponding to the incompressibility constraint, with respect to the endpoint conditions, described by a probability measure γ determining the state of the fluid at the initial and final times. We show in Chapter 2 by purely variational methods that the gradient of the pressure field, as an element of a space that is close to the dual of C^1, is a Hölder continuous function of γ for the Monge-Kantorovic distance. On the other hand, we prove in Chapter 4 that for all r>1 the pressure field, as an element of L^r_t L^1_x, cannot be a Lipschitz continuous function of γ for the Monge-Kantorovic distance. This last statement is linked to an ill-posedness result proved in Chapter 3 for the so-called kinetic Euler equation, a kinetic PDE interpreted as the optimality equation of the Incompressible Optimal Transport problem.In the second part, we are interested in the entropic regularization of the Incompressible Optimal Transport problem: the so-called Brödinger problem, introduced by Arnaudon, Cruzeiro, Léonard and Zambrini in 2017. On the one hand, we prove in Chapter 5 that similarly to what happens in the Incompressible Optimal Transport case, to a solution always corresponds a scalar pressure field acting as the Lagrange multiplier for the incompressibility constraint. On the other hand, we prove in Chapter 6 that when the diffusivity coefficient tends to zero, the Brödinger problem converges towards the Incompressible Optimal Transport problem in the sense of Gamma-convergence, and with convergence of the pressure fields. The results of Chapter 6 come from a joint work with L. Monsaingeon
Boulanger, Anne-Céline. "Modélisation, simulation et assimilation de données autour d'un problème de couplage hydrodynamique-biologie". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2013. http://tel.archives-ouvertes.fr/tel-00871141.
Texto completoDuverneuil, Patrick. "Etablissement de données physico-chimiques et cinétiques en vue d'essai de recristallisation de l'octogène à partir de solutions dans différents solvants : application au cristalliseur MSMPR". Toulouse, INPT, 1987. http://www.theses.fr/1987INPT015G.
Texto completoBellat, Jean-Pierre. "Données thermodynamiques et cinétiques des systèmes liquide-vapeur-adsorbant en vue de leur utilisation comme machine thermique a affinité : cas de la sépiolite et de la zéolithe 4a". Dijon, 1985. http://www.theses.fr/1985DIJOS017.
Texto completoMoine, Edouard. "Estimation d’énergies de GIBBS de solvatation pour les modèles cinétiques d’auto-oxydation : développement d’une banque de données étendue et recherche d’équations d’état cubiques et SAFT adaptées à leur prédiction". Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0295/document.
Texto completoLiquid phase oxidation of hydrocarbons (also called autoxidation) is central to a large number of processes in the petrochemical industry as it plays a key role in the conversion of petroleum feedstock into valuable organic chemicals. This phenomenon is also crucial in oxidation-stability studies of fuels and its derivatives (aging). These liquid-phase oxidation reactions entail radical mechanisms involving more than thousands of compounds and elementary reactions. Kinetic modelling of these kinds of reactions remains a significant challenge because it requires thermodynamic and kinetic parameters, which are not abundant in literature. The EXGAS software, developed at LRGP, is able to generate these kinds of models but only for oxidation reactions taking place in a gaseous phase. It is assumed that the nature of elementary reactions in the liquid and gaseous phases is the same. The unique need to transfer a kinetic mechanism from a gas phase to a liquid phase is to update kinetic rate constant values and equilibrium constant values (called thermokinetic constants) of mechanism reactions. Therefore, in the framework of this PhD thesis, a new method aimed at applying a correction term to thermokinetic constants of gaseous phases is proposed in order to obtain constants usable to describe liquid-phase mechanisms. This correction involves a quantity called partial molar solvation GIBBS energy. An analysis of the precise definition of this property led us to conclude that it can be simply expressed as a function of fugacity coefficients and liquid molar density. As a result, this property could also be expressed with respect to measurable thermodynamic quantities as activity coefficients or HENRY’s law constants. By combining all the experimental data related to these measurable properties that can be found in the literature, it was possible to develop a comprehensive databank of partial molar solvation GIBBS energies (called the CompSol database). This database was used to validate the use of the UMR-PRU equation of state to predict solvation quantities. Moreover, the bases of a new parameterization for SAFT-type equations of state were laid. It consists in estimating pure-component parameters of SAFT-like equation using a very simple, reproducible and transparent path for non-associating pure components. This equation was used to calculate partial molar GIBBS energy of solvation of pure and mixed solutes. Last, equations of state were combined with EXGAS software to model the oxidation of n-butane in the liquid phase
Moine, Edouard. "Estimation d’énergies de GIBBS de solvatation pour les modèles cinétiques d’auto-oxydation : développement d’une banque de données étendue et recherche d’équations d’état cubiques et SAFT adaptées à leur prédiction". Electronic Thesis or Diss., Université de Lorraine, 2018. http://www.theses.fr/2018LORR0295.
Texto completoLiquid phase oxidation of hydrocarbons (also called autoxidation) is central to a large number of processes in the petrochemical industry as it plays a key role in the conversion of petroleum feedstock into valuable organic chemicals. This phenomenon is also crucial in oxidation-stability studies of fuels and its derivatives (aging). These liquid-phase oxidation reactions entail radical mechanisms involving more than thousands of compounds and elementary reactions. Kinetic modelling of these kinds of reactions remains a significant challenge because it requires thermodynamic and kinetic parameters, which are not abundant in literature. The EXGAS software, developed at LRGP, is able to generate these kinds of models but only for oxidation reactions taking place in a gaseous phase. It is assumed that the nature of elementary reactions in the liquid and gaseous phases is the same. The unique need to transfer a kinetic mechanism from a gas phase to a liquid phase is to update kinetic rate constant values and equilibrium constant values (called thermokinetic constants) of mechanism reactions. Therefore, in the framework of this PhD thesis, a new method aimed at applying a correction term to thermokinetic constants of gaseous phases is proposed in order to obtain constants usable to describe liquid-phase mechanisms. This correction involves a quantity called partial molar solvation GIBBS energy. An analysis of the precise definition of this property led us to conclude that it can be simply expressed as a function of fugacity coefficients and liquid molar density. As a result, this property could also be expressed with respect to measurable thermodynamic quantities as activity coefficients or HENRY’s law constants. By combining all the experimental data related to these measurable properties that can be found in the literature, it was possible to develop a comprehensive databank of partial molar solvation GIBBS energies (called the CompSol database). This database was used to validate the use of the UMR-PRU equation of state to predict solvation quantities. Moreover, the bases of a new parameterization for SAFT-type equations of state were laid. It consists in estimating pure-component parameters of SAFT-like equation using a very simple, reproducible and transparent path for non-associating pure components. This equation was used to calculate partial molar GIBBS energy of solvation of pure and mixed solutes. Last, equations of state were combined with EXGAS software to model the oxidation of n-butane in the liquid phase
Sirjean, Baptiste. "Étude cinétique de réactions de pyrolyse et de combustion d'hydrocarbures cycliques par les approches de chimie quantique". Thesis, Vandoeuvre-les-Nancy, INPL, 2007. http://www.theses.fr/2007INPL093N/document.
Texto completoPetroleum fuels are the world’s most important primary energy source and the need to maintain their supply is a major actual challenge involving both economical and environmental features. Decreasing fuels consumption is one of the more efficient ways to reconcile the goals of energy price and environmental protection. Numerical simulations become therefore a very important tool to optimize fuels and motors. Detailed chemical kinetic models are required to reproduce the reactivity of fuels and to characterize the amount of emitted pollutants. Such models imply a very large number of chemical species and elementary reactions, for a given species, and the determination of thermodynamic and kinetic data is a critical problem. Nowadays, quantum chemistry methods are able to calculate accurately thermodynamic data for a large number of chemical systems and to elucidate the reactivity of these systems. In this work we have used quantum chemistry to study the unimolecular reactions (initiation, molecular reactions, ß-scissions, cyclic ethers formations) involved in the decomposition of monocyclic and polycyclic hydrocarbons. From the results of quantum chemical calculations, a detailed chemical kinetic mechanism of the pyrolysis of a polycyclic alkane has been developed and validated against experimental data
Bigorgne, Léo. "Propriétés asymptotiques des solutions à données petites du système de Vlasov-Maxwell". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS164/document.
Texto completoThe purpose of this thesis is to study the asymptotic properties of the small data solutions of the Vlasov-Maxwell system using vector field methods for both the electromagnetic field and the particle density. No compact support asumption is required on the initial data. Instead, we make crucial use of the null structure of the equations in order to deal with a resonant phenomenon caused by the particles approaching the speed of propagation of the Maxwell equations. Due to the robustness of vector field methods and contrary to previous works on this topic, we also study plasmas with massless particles.We start by investigating the high dimensional cases d ≥ 4 where dispersive effects allow us to derive strong decay rate on the solutions of the system and their derivatives. For that purpose, we proved a new decay estimate for solutions to massive relativistic transport equations. In order to obtain an analogous result for massless particles, we required the velocity support of the distribution function to be initially bounded away from $0$ and we then proved that this assumption is actually necessary. The second part of this thesis is devoted to the three dimensional massless case, where a stronger understanding of the null structure of the Vlasov-Maxwell system is essential in order to derive the optimal decay rate of the null components of the electromagnetic field, the velocity average of the particle density and their derivatives. We then focus on the asymptotic behavior of the small data solutions of the massive Vlasov-Maxwell system in 3d. Specific problems force us to modify the vector fields used previously to study the Vlasov field in order to compensate the worst error terms in the commuted transport equations. Finally, still for the massive system in 3d, we restrict our study of the solutions to the exterior of a light cone. The strong decay properties satisfied by the velocity average of the particle density in such a region permit us to relax the hypothesis on the initial data and lead to a much simpler proof
Malangi, Gajendramurthy Chunchesh. "Vers la conception d'une sonde RMN immersible pour le suivi des réactions en solution". Electronic Thesis or Diss., Strasbourg, 2024. http://www.theses.fr/2024STRAF007.
Texto completoThis endeavour represents a pioneering effort to design and develop a cost-effective low-field Dip-NMR or Immersible NMR system dedicated to monitoring reaction mixtures at the closest possible source of information. While we have successfully designed and optimized the first version of prototype capable of acquiring single scanned NMR spectra of pure samples, further focused study and research are highly warranted to develop and integrate prototype into an immersible probe unit capable of multi-channel acquisition to realize the proposed Dip-NMR system. The NMR spectra obtained from Dip-NMR system were notably broad and necessitated dedicated chemometric methods for quantification and kinetic data extraction. Known reactions were monitored on a high-field high-resolution NMR spectrometer, with the kinetic data from this instrument serving as benchmark data for comparison and evaluation against the data obtained from Dip-NMR system. Various chemometric methods were explored and tested on the mimicked spectra for quantification and kinetic data extraction, with the results subsequently compared with the benchmark data. In parallel with the project’s goal, hydrosilylation reactions involving organic substrates such as nitriles, cyclic amides, and esters were catalyzed using an Ir(III) catalyst and monitored on a high-field high-resolution NMR spectrometer. These investigations have successfully yielded valuable insights into the reactions, contributing to a deeper understanding of the processes involved and laid important reference kinetic data for future testing of an advanced Dip-NMR probe prototype
Puisieux, Sarah. "Etude des effets Sunyaev-Zel'dovitch cinétique et relativiste dans les données Planck". Phd thesis, Université Paris-Diderot - Paris VII, 2013. http://tel.archives-ouvertes.fr/tel-01019928.
Texto completoPuisieux, Sarah. "Etude de l'effet Sunyaev-Zel'dovich cinétique et relativiste dans les données Planck". Paris 7, 2013. http://www.theses.fr/2013PA077232.
Texto completoThe Sunyaev-Zeldovich effects correspond to the inverse-Compton diffusion of photons from the cosmic microwave background on the gaz of clusters of galaxies. The aim of this work is to study ail the aspects of kinetic and relativistic thermic SZ in the Planck data. We have developec several filters, specially designed to extract the SZ effects. These filters allow us to use ail the Planck frequencies in an optimal way. The kinetic effect is proportional to the radial peculiar velocity of clusters of galaxies. We have studied these velocities individually but also statistically. We have in particular measured for the first time the average velocity of clusters, that is found in agreement with zero, which constitutes a proof of the cosmological principle. We have also studied the bulk flow of clusters and excluded several models of inhomogeneous universe with a very high confidence and put an upper limit on the velocity variance. The kinetic SZ effect can also be explored through the pairwise momentum of halos of galaxies. The results present a significant detection. Finally, we have analyzed the thermal relativistic SZ effect via its dependency to cluster temperatures. We have in particular provided evidence of its impact on the measurement of the kinetic SZ effect
Bessière, Hélène. "Assimilation de données variationnelle pour la modélisation hydrologique distribuée des crues à cinétique rapide". Phd thesis, Toulouse, INPT, 2008. https://hal.science/tel-04426689.
Texto completoIntense flash floods, produced by severe thunderstorms, represent the most destructive hazard in the Mediterranean region. Human lives and properties are increasingly exposed to flood risks. Therefore, there is a clear need to improve real-time monitoring and flood forecasting. The HydroEco research group at IMFT (Institute of Fluid Mechanics of Toulouse) developed the MARINE model (Modélisation de l'Anticipation du Ruissellement et des Inondations pour des évéNements Extrêmes), a distributed physically-based model, in order to forecast this kind of flood. A data assimilation process called the adjoint state method is implemented into the MARINE model. The principle of the adjoint method is to consider input parameters as control variables and optimize them by minimizing a cost function measuring the discrepancy between observations and model simulations. The procedure is tested on the Mediterranean Gardon d'Anduze catchment. A previous sensitivity analysis allows identifying the most sensitive parameters in order to avoid the “non-uniqueness problem” and overparameterization. Then a first application of the adjoint method aims at calibrating the model. The method enables to evaluate the model performance and contributes to either the validation of physical hypothesis or perspectives for the model structure improvements. A consistent set of parameters, in accordance with results achieved with a Monte-Carlo procedure, is then identified and simulated hydrographs are limited into a reduced range of uncertainties. The second application of the method is dedicated to flash flood forecasting. The first strategy employed is to use outlet flow information during the rising flood phase to estimate the peak. The second strategy employed is to use information of intermediate upstream gauging stations to predict the outlet flow. Both strategies allow anticipating, a few hours in advance, the peak which is crucial from an operational point of view
Bessière, Hélène. "Assimilation de données variationnelle pour la modélisation hydrologique distribuée des crues à cinétique rapide". Phd thesis, Toulouse, INPT, 2008. http://oatao.univ-toulouse.fr/7761/1/bessiere1.pdf.
Texto completoTourlet, Sébastien. "Proposition d’une stratégie d’analyse statistique des données de puces à ADN décrivant une cinétique d’expression génique". Thesis, Tours, 2009. http://www.theses.fr/2009TOUR3134.
Texto completoMicroarray results were blamed because of their lack of concordance. Moreover, the huge candidate gene lists from statistical filterings are not useful for biologists. FDA proved that the lack of reliability between microarray experiments came from the choice of gene filtering indicators. In this context, a filtering method was developed based on expression curve shape modelling with the use of Log 2 of fold-change between kinetic points. Actually, the co-regulated genes display similar expression shape but with heterogeneous expression level.Our method was developed and validated thanks to two independent microarray experiments (Affymetric®) from mouse embryonic ovaries. Therefore, a short and relevant list of genes was obtained. Thus, a study of results linked to ovarian differentiation permitted to identify nine new candidate genes that were in silico validated. These genes might be biologically tested (i.e. RT PCR) by the scientific community
Himoudi, Abdelilah. "Simulation numérique de la cinétique des ions dans les gaz rares faiblement ionisés : détermination des données de base". Toulouse 3, 1993. http://www.theses.fr/1993TOU30171.
Texto completoBenabdessadok, Mohamed Dinori. "Théorie cinétique des électrons dans les plasmas froids non thermiques. Détermination des données de base dans les gaz d'échappement". Toulouse 3, 1997. http://www.theses.fr/1997TOU30029.
Texto completoPago, Catherine. "Etude expérimentale et modélisation de la nucléophilie d'amines bioactives". Aix-Marseille 3, 1998. http://www.theses.fr/1998AIX30055.
Texto completoPersis, Stéphanie de. "Cinétique chimique en phase homogène appliquée au dépôt chimique à partir d'une phase gazeuse : évaluation des données, interprétation et réduction des systèmes complexes". Perpignan, 2001. http://www.theses.fr/2001PERP0441.
Texto completoNumerical modeling of the Chemical Vapour Deposition (CVD) process requires a good description of the elementary process occuring in the gas phase (transfer, homogeneous chemical reactions,. . . ) and at the growing surface (heterogeneous reactions, nanostructure formation,. . . ). This work is aimed at the investigation of the reaction mechanisms that develop in the gas phase. Various tools and a three-step procedure of construction, analysis and reduction have been developed in order to better understand reaction mechanisms and to integrate them both in reactor models (at a macroscopic scale) and in growth models (at the atomic scale). The above procedure is widely used in the combustion field but it is almost unknown in CVD
Caspard, Emmanuel. "La dolomitisation des réservoirs carbonates de plate-forme : des données géologiques à la modélisation : exemple du grand banc des Bahamas". Paris 6, 2002. http://www.theses.fr/2002PA066486.
Texto completoMula, Olga. "Quelques contributions vers la simulation parallèle de la cinétique neutronique et la prise en compte de données observées en temps réel". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2014. http://tel.archives-ouvertes.fr/tel-01068691.
Texto completoGaouar, Adil. "Théorie cinétique et données de base des électrons dans les plasmas non thermiques : application aux milieux d'excitation des lasers à excimères". Toulouse 3, 1995. http://www.theses.fr/1995TOU30287.
Texto completoMula, Hernandez Olga. "Quelques contributions vers la simulation parallèle de la cinétique neutronique et la prise en compte de données observées en temps réel". Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066201/document.
Texto completoIn this thesis, we have first developed a time dependent 3D neutron transport solver on unstructured meshes with discontinuous Galerkin finite elements spatial discretization. The solver (called MINARET) represents in itself an important contribution in reactor physics thanks to the accuracy that it can provide in the knowledge of the state of the core during severe accidents. It will also play an important role on vessel fluence calculations. From a mathematical point of view, the most important contribution has consisted in the implementation of algorithms that are well adapted for modern parallel architectures and that significantly decrease the computing times. A special effort has been done in order to efficiently parallelize the time variable by the use of the parareal in time algorithm. On a second stage, we have developed the foundations of a method with which we could use MINARET to monitor in real time the population of neutrons during the operation of the reactor. One of the major difficulties relies in the necessity of providing computations in real time. This question has been addressed by proposing an extension of the Empirical Interpolation Method (EIM) thanks to which a well-posed interpolation procedure has been defined for functions belonging to Banach spaces. This is possible thanks to the use of interpolating linear forms instead of the traditional interpolation points and a part of this thesis has been devoted to the understanding of the theoretical properties of this method (convergence analysis under the hypothesis of small Kolmogorov n-width and stability of the procedure)
Hennad, Ali. "Cinétique des ions dans les gaz moléculaires par simulations de Monte Carlo classique et optimisée : détermination des données de base dans l'air". Toulouse 3, 1996. http://www.theses.fr/1996TOU30184.
Texto completoGehan, Charlotte. "Évolution de la rotation du cœur des étoiles sur la branche des géantes rouges : des mesures à grande échelle vers une caractérisation du transport de moment cinétique". Electronic Thesis or Diss., Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEO021.
Texto completoAsteroseismology consists in probing stellar interiors through the detection of seismic waves. Red giants are evolved low-mass stars that have exhausted hydrogen in their core. These stars are solar-type pulsators presenting mixed modes that allow us to have a direct access to the physical properties of their core. The available seismic measurements indicate that one or several mechanisms that remain poorly understood counterbalance the acceleration ofthe core rotation, resulting from its contraction, by transporting angularmomentum. The greatest part of this PhD thesis was devoted to the development of a method allowing a measurement as automated as possible of the mean core rotation of stars on the red giant branch that were observed by the Kepler satellite (NASA). The measurements that were derived for almost 900 stars highlight that the core rotation is almost constant along the red giant branch, with values largely independent of the stellar mass. The second part of this PhD thesis is devoted to the interpretation of these results based on stellar modelling. The challenge consists in using the large-scale measurements obtainedin the first part to characterise the quantity of angular momentum that has to be extracted from each layer of the core, at different timesteps on the red giant branch, for different stellar masses
Mouton, Nicolas. "Ré-investigation de la photo-dynamique du salicylidène aniline par spectroscopie d'absorption transitoire femtoseconde et analyse multivariée des données". Phd thesis, Université des Sciences et Technologie de Lille - Lille I, 2011. http://tel.archives-ouvertes.fr/tel-00689167.
Texto completoGehan, Charlotte. "Évolution de la rotation du cœur des étoiles sur la branche des géantes rouges : des mesures à grande échelle vers une caractérisation du transport de moment cinétique". Thesis, Paris Sciences et Lettres, 2018. http://www.theses.fr/2018PSLEO021/document.
Texto completoAsteroseismology consists in probing stellar interiors through the detection of seismic waves. Red giants are evolved low-mass stars that have exhausted hydrogen in their core. These stars are solar-type pulsators presenting mixed modes that allow us to have a direct access to the physical properties of their core. The available seismic measurements indicate that one or several mechanisms that remain poorly understood counterbalance the acceleration ofthe core rotation, resulting from its contraction, by transporting angularmomentum. The greatest part of this PhD thesis was devoted to the development of a method allowing a measurement as automated as possible of the mean core rotation of stars on the red giant branch that were observed by the Kepler satellite (NASA). The measurements that were derived for almost 900 stars highlight that the core rotation is almost constant along the red giant branch, with values largely independent of the stellar mass. The second part of this PhD thesis is devoted to the interpretation of these results based on stellar modelling. The challenge consists in using the large-scale measurements obtainedin the first part to characterise the quantity of angular momentum that has to be extracted from each layer of the core, at different timesteps on the red giant branch, for different stellar masses
Mouton, Nicolas. "Ré-investigation de la photo-dynamique du salicylidène aniline par spectroscopie d’absorption transitoire femtoseconde et analyse multivariée des données". Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10090/document.
Texto completoThis work is interested in the photo-dynamics of photochromism of salicylidene aniline (SA) in solution aiming at proposing a general mechanism. As the photochormism of SA involves an ultrafast intramolecular proton transfer, the experimental study consisted mainly in femtosecond transient absorption spectroscopy at different excitation wavelengths.The observation of ultrafast photo-induced processes by pump-probe spectroscopy techniques requires measuring and taking into account the instrumental response function. Indeed some physical effects affect the structure of spectrokinetic data, some distortions may be observed, as well as convolution limiting the time resolution of the measurement. The first part of this work dealt with an adaptation of multivariate chemometric tools, to take into account these specificities. The proposed approach implements a dedicated kinetic constraint into the multivariate curve resolution-alternating least squares method (MCR-ALS). The methodological developments were validated on simulated data and then being applied to the spectroscopic study of SA.The main points are: 1) the intramolecular proton transfer, which was estimated at 60 fs, 2) the existence of a competitive rotation mechanism which was characterized, 3) the excitation wavelength dependence of quantum yields values. Finally, a complete characterization of the photo-induced processes of SA, i.e. the reaction rates and the spectra of all the transient species, was provided and discussed
Brédif, Mathieu. "Modélisation 3D de bâtiments : reconstruction automatique de superstructures de toits et recalage cinétique de toits polyédriques prenant en compte la topologie". Phd thesis, Paris, Télécom ParisTech, 2010. https://pastel.hal.science/pastel-00006232.
Texto completoThere is nowadays a growing demand for increasingly more accurate 3D city models. Whereas recent works have lead to the robust generation of polyhedral building models, they do not model roof superstructures such as chimneys or dormer windows, and may feature large geometric and topological errors. We propose an approach to refine geometrically and semantically a superstructure-less approximate building model, using a Digital Surface Model (DSM). This iterative approach alternates between superstructure reconstructions and geometric fitting of the main roof planes. Superstructure detection and reconstruction are based on a library of parametric superstructure models. A set of disjoint superstructures is searched to explain the height differences between the DSM and the building model, reducing the search to a maximum weighted clique problem. The fitting step uses the previously detected superstructures to refine the main roof plane estimations. It corrects both geometric simplifications such as an erroneous roof symmetry, and topological simplifications such as the merging of close vertices of the polyhedral building model. The proposed representation of the building geometry uses the planes supporting each polyhedral facet, which is more intuitive in this context than the usual representation using the vertex locations. We introduce the trihedralization problem of splitting vertices that become over-constrained after updating their adjacent facet supports into well-defined vertices at the intersection of 3 planes. We propose a novel kinetic data structure that prevents facet self-intersections throughout the iterative reestimation of their supporting planes
Brédif, Mathieu. "Modélisation 3D de bâtiments : reconstruction automatique de superstructures de toits et recalage cinétique de toits polyédriques prenant en compte la topologie". Phd thesis, Télécom ParisTech, 2010. http://pastel.archives-ouvertes.fr/pastel-00006232.
Texto completoBerro, Julien. "Du monomère à la cellule : modèle de la dynamique de l'actine". Université Joseph Fourier (Grenoble), 2006. http://www.theses.fr/2006GRE10226.
Texto completoActin filaments are biological polymers that are very abundant in eucaryot cytoskeleton. Their auto-assembly and auto-organization are highly dynami. And are essential in cell motility and membrane deformations. Ln this thesis we propose three approaches, on different scales, in order to enlighten mechanisms for the regulation ofassembly of, organization of and production of force by biological filaments such as actin filaments. First, we have developed a stochastic multi-agent simulation tool for studying biological filaments taking into consideration interactions on the nanometer scale. This new tool allowed us to bring out the acceleration of actin monomer turnover due to fragmentation of filaments by ADF/Cofilin and the symmetry breaking induced by thisprotein, which agree weil with experimental data from L. Blanchoin team (CEA Grenoble). Secondly, we studied a continuou model for filament buckling, providing, on the one hand, an estimation of forces exerted in vitro or in vivo with respect to extremity attachment conditions and, on the other hand, limit conditions for buckling. Thirdly, we developed a framework for organizing kinetic biochemical data from reaction networks, which was used for the regulation of actin polymerization. These three modeling approaches improved the knowledge on actin dynamics and are useful complements for experimental approaches in biology
Simeoni, Chiara. "Méthodes numériques pour des équations hyperboliques de type Saint-Venant". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2002. http://tel.archives-ouvertes.fr/tel-00922706.
Texto completoHoang, Tuan-Nghia. "Modélisation du mouvement intersegmentaire in-vivo du rachis cervical". Compiègne, 2008. http://www.theses.fr/2008COMP1786.
Texto completoThe cervical spine is an anatomical structure complex of the human body. It composes by the seven vertebrae, the intervertebral discs and the system of the ligaments and muscles. This structure assures many of biomechanical functions: it supports and stabilizes the head; it allows the important mobility of the head; it contains and protects the system of spinal cord. The aim of this subject is to ameliorate the understanding of cervical spine functioning in-vivo for the diagnostic and the classification of the neck pathologies. This study is methodology to modelling of the continuous intersegmental motion in flexion/extension of cervical spine based on the experimental data in-vivo. First, an experimental protocol is proposed by using simultaneously two techniques, the X-rays images and the external motion markers, which permits the acquisition combined by the geometrical and kinematical data. Then, two mechanical models, an osteoarticular model and a musculoskeletal model, of the cervical spine are developed by the modelling hypothesis. Finally, the hypothesis are justified and the responses of model are confronted with the experimental data in-vivo also the literature. The results of this study allow determining not only the kinematic and kinetic parameters associated with the continuous motion in flexion/extension, but also the mechanical behaviour of the segments and the components of the cervical spine during this motion in-vivo
Mbodji, Mamadou. "Conception et dimensionnement de réacteurs-échangeurs microstructurés pour la production de gaz de synthèse par vaporeformage du méthane". Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0256/document.
Texto completoSteam Methane Reforming (SMR) of natural gas is characterized by generation of an excess of steam and their low thermal efficiency resulting in a very large device with important heat losses. One of the possible keys to make this process more profitable is to optimize heat transfer by changing the reactor design. A microstructured heat exchanger reactor has been retained. It enables to have fast heat and mass transfers and therefore allow increasing catalytic activity. However, this change in production technology must be accompanied by the development of highly active catalysts (MgAl2O4) that enable to reach high methane conversion (80%, 20 bar, 850°C) at low residence time (150 ms). The concept feasibility and catalysts performance have been validated on one channel in industrial process conditions. Then, a detailed model for acquisition of reaction kinetics has been developed and validated from experimental catalytic tests. For heat exchanger reactor design, two modeling approaches have been developed: by considering that the catalyst is highly active and enables to reach instantaneous equilibrium conversion on the coated catalytic walls of the reactor and by tacking the measured kinetics. Simulation of these models by considering technical constraints on the design enabled to find channel characteristic dimensions, heat power needed and the optimum number of channel which determine the heat exchanger reactor volume. Two fast methods for preliminary design of heat-exchanger reactors have been developed. By using heat exchanger reactor, it is possible to suppress steam excess generation and to reduce syngas production cost
Kon, Kam King Guillaume. "Revisiting Species Sensitivity Distribution : modelling species variability for the protection of communities". Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10194/document.
Texto completoSpecies Sensitivity Distribution (SSD) is a method used by scientists and regulators from all over the world to determine the safe concentration for various contaminants stressing the environment. Although ubiquitous, this approach suffers from numerous methodological flaws, notably because it is based on incomplete use of experimental data. This thesis revisits classical SSD, attempting to overcome this shortcoming. First, we present a methodology to include censored data in SSD with a web-tool to apply it easily. Second, we propose to model all the information present in the experimental data to describe the response of a community exposed to a contaminant. To this aim, we develop a hierarchical model within a Bayesian framework. On a dataset describing the effect of pesticides on diatom growth, we illustrate how this method, accounting for variability as well as uncertainty, provides benefits to risk assessment. Third, we extend this hierarchical approach to include the temporal dimension of the community response. The objective of that development is to remove the dependence of risk assessment on the date of the last experimental observation in order to build a precise description of its time evolution and to extrapolate to longer times. This approach is build on a toxico-dynamic model and illustrated on a dataset describing the salinity tolerance of freshwater species
Haghebaert, Marie. "Outils et méthodes pour la modélisation de la dynamique des écosystèmes microbiens complexes à partir d'observations expérimentales temporelles : application à la dynamique du microbiote intestinal". Electronic Thesis or Diss., université Paris-Saclay, 2023. http://www.theses.fr/2023UPASM036.
Texto completoThis thesis stems from the European project Homo.symbiosus, which investigates the equilibrium transitions of interactions between the host and its intestinal microbiota. To study these transitions, we pursue two directions: the mechanistic modeling of host-microbiota interactions and the analysis of temporal microbial count data.We enriched and simulated a deterministic model of the intestinal crypt using the EDK numerical scheme, particularly studying the impact of different parameters using the Morris Elementary Effects method. This model proved capable of simulating, on one hand, symbiotic and dysbiotic interaction states and, on the other hand, transition scenarios between states of dysbiosis and symbiosis.In parallel, a compartmental ODE model of the colon, inspired by existing studies, was developed and coupled with the crypt model. The thesis contributed to the enhancement of bacterial metabolism modeling and the modeling of innate immunity at the scale of the intestinal mucosa. A numerical exploration allowed us to assess the influence of diet on the steady state of the model and to study the effect of a pathological scenario by mimicking a breach in the epithelial barrier.Furthermore, we developed an approach to analyze microbial data aimed at assessing the deviation of microbial ecosystems undergoing significant environmental disturbances compared to a reference state. This method, based on DMM classification, enables the study of ecosystem equilibrium transitions in cases with few individuals and few time points. Moreover, a curve classification method using the SBM model was applied to investigate the effects of various disturbances on the microbial ecosystem; the results from this study were used to enrich the host-microbiota interaction model
Pasquet, Camille. "Evaluation de la biodisponibilité du nickel, cobalt et manganèse dans les poussières de sols ultramafiques et développement d'un outil de bioindication lichénique des poussières émises par les activités minières en Nouvelle Calédonie". Thesis, Nouvelle Calédonie, 2016. http://www.theses.fr/2016NCAL0008/document.
Texto completoBioavailability estimation of nickel, cobalt and manganese in dust from ultramafic soils likely to be mobilized by wind and~eve lopment of a bioindication tool using lichen for dust emitted by mining activities in New Caledonia New Caledonian altered ultramafic soils, particularly rich in Ni, Co, Mn and Cr, are extracted by opencast mines which generale dust rich in metals. The objective of th is work is to develop approaches for environmental risk assessment of dust emitted by opencast mines and nickel ore metallurgical plants. The assessmentof metals' bioavailable fraction from two dust granulometrie size fractions, one less than 100 IJm which is mobilizable by wind (F<1001Jm,) and another one able to penetrate the respiratory system (PM 1 0), has been determined by kinetic extraction with EDT A. The development of a new separation deviee based on particle transport subjected to a nitrogen flux in a horizontal tube has been necessary for PM1 0 segregation. Kinetic extractions le ad to the distinction of th ree metal pools: rapidly labile, less rapidly labile and non-bioavailable. Trace metal potentially bioavailable concentrations were always high and the less rapidly labile pool is always the most concentrated pool. Concerning F<1 001Jm, the less rapidly kinetic constant of the less rapidly labile pool is weaker for mining soils than forest soils. F<1001Jm fractions from mining soils representa more durable reserve in trace metal than the same fraction from forest soils. Bioindication using lichens with compositional data analysis of their metal concentration allow defining an indicator of emission dispersion. This methodology could support air quality monitoring networks in New Caledonia
Adam, Rémi. "Observation des amas de galaxies par effet Sunyaev-Zel'dovich et de la polarisation du fond diffus cosmologique : de Planck à NIKA". Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAY056/document.
Texto completoThe measurement of the matter distribution in the Universe provides valuable tests for cosmology. It can be traced at various steps of the formation of structures using the analysis of the primary and secondary anisotropies in the Cosmic Microwave Background (CMB). This thesis focuses on the data analysis of the observations of the Planck satellite and that of the ground-based camera NIKA installed at the IRAM-30m telescope.The first part introduces the context, focussing on: 1) the inflation, which provides a natural origin for the matter fluctuations seen in the Universe; 2) the reionization, which corresponds to the moment when the first stars form; 3) clusters of galaxy, that are the building blocks of the more recent Universe.The second part focuses on the data reduction of the NIKA data. The development of the data reduction pipeline, allowing to go from raw data to maps, is presented. It is dedicated for the newly developed kinetic inductance detectors used by NIKA. Tools and simulations are also constructed to characterize the maps.The third part is dedicated to the observation and the analysis of galaxy clusters through the Sunyaev-Zel'dovich (SZ) effect, i.e. the inverse Compton interaction of CMB photons and free electrons in clusters. Once recovered, the SZ maps are combined to X-ray data to measure the matter content and thermodynamic properties of the observed clusters. The main results are: the first observation of the SZ effect with kinetic inductance detectors, the measurement of the pressure profile of a high redshift cluster ($z=0.89$), the study of point source contamination in a resolved cluster, and the SZ mapping in a triple merger.The last part is dedicated to the analysis of Planck polarization data. In particular, we discuss large angular scale systematics and the tools developed to identify and correct for them. The large scales CMB polarization data allows both to search for the imprint of the quantum fluctuations generated during inflation, and to measure the reionization
Madon, Michel. "Cellules à enclumes de diamant et microscopie électronique en transmission : étude expérimentale des transformations de phase du manteau terrestre". Paris 6, 1986. http://www.theses.fr/1986PA066123.
Texto completoHornus, Samuel. "Maintenance de la visibilité d'un point mobile, et applications". Phd thesis, 2006. http://tel.archives-ouvertes.fr/tel-00344930.
Texto completoWe take two different approaches to this problem. In one, we show how one can maintain the so-called visibility polyhedron of the moving point, in an exact fashion. We apply a variant of the algorithm to the construction of the visibility complex of a set of disjoint polytopes.
The second approach is motivated by the need to render complex 3D scenes at interactive rates. We propose an algorithm that decomposes a 3D scene into simple cells related together with simple visibility relationships represented as a graph. The scene is drawn as the graph is traversed, allowing pruning to speed up rendering. We also provide an efficient algorithm for real-time rendering of hard shadows.
Heredia, Ortiz Roberto. "Modélisation toxicocinétique du benzo(a)pyrène et 3-hydroxybenzo(a)pyrène pour l’interprétation des données de surveillance biologique de l’exposition chez les travailleurs". Thèse, 2014. http://hdl.handle.net/1866/11765.
Texto completoMany workers are exposed to polycyclic aromatic hydrocarbons (PAHs). Benzo(a) pyrene (BaP) is part of this group of pollutants. This substance has been classified as a known carcinogen in humans. To assess exposure to carcinogenic PAHs, several researchers have proposed using the measurement of 3-hydroxybenzo(a)pyrene (3-OHBaP) in the urine of exposed workers. In this project, two modeling approaches were developed and applied to enable a better understanding of the toxicokinetics of BaP and its biomarker of current interest, 3-OHBaP, to help interpret the results of biological monitoring. A multi-compartment toxicokinetic model was developed based on the data previously obtained in rats by our group of research. According to the model, BaP injected intravenously is rapidly distributed from blood to tissues (t½ ≈ 4 h), with a particular affinity for lungs and lipid components of tissues. Subsequently, BaP is distributed to the liver and the skin. Once in the liver, BaP is promptly metabolized and 3-OHBaP is formed with a half-life of about 3 h. Pulmonary biotransformation of BaP was also taken into account, but its contribution to the overall kinetics of BaP was considered negligible. Once formed, 3-OHBaP is distributed to various organs almost as fast as the parent compound (t½ ≈ 2 h). An accumulation of 3-OHBaP profile is present in the kidneys because of the difference between the uptake rate (t½ = 28 min) and the ouput rate (t½ = 4.5 h). Total clearance of 3-OHBaP from the blood stream is primarily governed by the rate of transfer of the bile to the gastrointestinal tract (t ½ ≈ 4 h). The multi-compartment toxicokinetic model was able to simulate an independent set of published 3-OHBaP urinary profiles. This toxicokinetic compartmental model has proved useful for the determination of the main biological features of the kinetics of BaP and 3-OHBaP. Thereafter, a physiological pharmacokinetic model (PBPK) reproducing the fate of BaP and 3-OHBaP rats was built. Organs (or tissues) represented as compartments were selected based on experimental data obtained in vivo in rats. Partition coefficients, coefficients of permeability, biotransformation rates, excretion parameters, and absorption fraction for different exposure routes were obtained directly from the profiles of BaP and 3-OHBaP in blood, various tissues and excreta. The values of these parameters were calculated by Monte Carlo procedures. Sensitivity analyses were then performed to ensure the stability of the model and to determine the most sensitive parameters. This modeling has identified the following features: 1) a high sensitivity of hepatic metabolism and elimination rates of BaP and 3-OHBaP; 2) a large distribution of BaP in the lungs compared to other tissues; 3) a considerable distribution of BaP in adipose tissues and liver; 4) a significant distribution of 3-OHBaP in the kidneys; 5) a diffusion-limited transfer of BaP in the lungs, 6) a diffusion-limited transfer of 3-OHBaP in lungs, adipose tissues and kidneys; and 7) a significant entero-hepatic recycling of 3-OHBaP. Following a series of analysis of goodness of fit, the probabilites that the model simulations reproduced the experimental data due to pure chance were always below 10%, for the four routes of exposure: intravenous, oral, dermal and respiratory. Subsequently, we have extrapolated the kinetic models from rats to humans in order reproduce the temporal evolution of 3-OHBaP biomarker of exposure in the urine of workers occupationally expose. Results of these models were then compared to simulations obtained with a single compartment toxicokinetic model to verify the comparative usefulness of simple and complex model. Both types of models have been constructed from blood, tissue, urinary and faecal profiles of BaP and 3-OHBaP in rats. These data were obtained in vivo by intravenous, subcutaneous, oral and respiratory exposure. The models were extrapolated to humans taking into account the essential biological determinants of kinetic differences between rats and humans. Results showed that inhalation was not the primary route of exposure for many workers studied. The values of air concentrations of BaP used to simulate the urinary excretion profiles were different from those measured in the air. Dermal exposure to BaP seemed to better predict the temporal patterns observed. Finally, the two types of modeling have been proved useful to reproduce and to interpret experimental data obtained in workers.