Tesis sobre el tema "Méthode de la différentiation complexe"
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Massat, Christine. "Une nouvelle méthode d'optimisation globale basée sur la différentiation automatique". Toulouse 3, 1997. http://www.theses.fr/1997TOU30085.
Texto completoCotte, Romain. "L'enjeu de la différentiation automatique dans les méthodes de Newton d'ordres supérieurs". Mémoire, Université de Sherbrooke, 2010. http://savoirs.usherbrooke.ca/handle/11143/4884.
Texto completoVincent, Hugo. "Simulations et analyses de sensibilité du bruit produit des écoulements cisaillés". Electronic Thesis or Diss., Ecully, Ecole centrale de Lyon, 2024. http://www.theses.fr/2024ECDL0007.
Texto completoIn this PhD work, sensitivity studies are carried out for turbulent shear flows using direct noise computations and the complex differentiation method.First, the complex differentiation method is applied to two-dimensional mixing layers to investigate its capacity to highlight the effects of a parameter on the aerodynamic noise.For that, direct numerical simulations of mixing layers are performed using this method for different Mach numbers, Reynolds numbers and mesh spacings.In each case, the derivatives of the noise levels with respect to one of the three parameters are obtained using the complex differentiation method.The results are in good agreement with others from the literature and parametric studies.They indicate that the complex differentiation method can be used to describe the effects of physical parameters and of the grid resolution on the sound produced by a high-speed flow.Secondly, the complex differentiation method is applied to the study of the receptivity mechanism occurring when an acoustic wave reflects at the nozzle lip of a jet.For this purpose, using the results of a simulation of a jet impinging on a plate, an imaginary amplitude acoustic pulse is introduced at a given time in the near-nozzle region outside the jet.The sensitivity of the near-nozzle mixing layers to an acoustic disturbance is then determined using the complex differentiation method.This sensitivity is used to highlight the excitation of an instability wave by the acoustic disturbance.Finally, the influence of nozzle-exit conditions (velocity profile and turbulence level) on the tonal noise components generated by subsonic impinging jets is investigated.For that, jets with different nozzle-exit velocity profiles, several boundary-layer excitation levels, at Mach numbers of 0.6 or 0.9, impinging on a plate located at 6 or 8 nozzle radii from the nozzle, are simulated.The results show that the nozzle-exit conditions significantly affect the amplitude of the tonal noise components and that impinging jets at Mach numbers below 0.65, which are generally non-resonant, can be resonant for specific nozzle-exit conditions.The effects of the nozzle-exit conditions are found to result from changes in the development of the jet mixing layers, which lead to differences in the amplification properties of the Kelvin-Helmholtz instability waves between the nozzle and the plate, and in the energy contained in the coherent structures of the jets near the impingement region
Forestier, Romain. "Développement d'une méthode d'identification de paramètres par analyse inverse couplée avec un modèle éléments finis 3d". Phd thesis, École Nationale Supérieure des Mines de Paris, 2004. http://pastel.archives-ouvertes.fr/pastel-00001362.
Texto completoLampoh, Komlanvi. "Différentiation automatique de codes mécaniques : application à l'analyse de sensibilité des tôles sandwich aux paramètres de modélisation". Thesis, Université de Lorraine, 2012. http://www.theses.fr/2012LORR0220/document.
Texto completoIn engineering, for a better understanding of the mechanical behavior of a structure submitted to some perturbation of the modeling parameters, one often proceed to a sensitivity analysis. This provides quantitative and qualitative information on the behavior of the model under study and gives access to gradients that may be used in identification and optimization methods. In this thesis, we demonstrate that this information may be obtained at a low development effort by applying an Automatic Differentiation (AD) tool to the computer code that implements the model. We adapt the AD techniques to the Asymptotic Numerical Method (ANM), in its Diamant version for sensitivity computations of numerical solutions of nonlinear problems discretized through a finite element method. We discuss in a generic manner both the theoretical aspects and the implementation of several algorithms written in Matlab. Applications are concerned with sandwich beams and sandwich plates in both the static and dynamic (free vibration) cases. Sensitivities are computed with respect to geometric and mechanical parameters, and with respect to elementary stiffness matrix. The generality of our developments allows to take into account several viscoelastic laws with no additional effort. Three kinds of viscoelastic models are studied: constant complex modulus, low damping and higher damping. In comparison with the finite difference approximation often used in mechanics, our approach provides more accurate results for the sensitivity of the structure response to a perturbation of the modeling parameters. It also allows a reduction of the computation effort
Beaume, Grégory. "Modélisation et simulation de l'écoulement d'un fluide complexe". Phd thesis, Paris, ENMP, 2008. http://pastel.paristech.org/5458/01/these_G-Beaume.pdf.
Texto completoThis work is dedicated to numerical simulation of flow of solid-liquid mixtures. The fluid flow obeys a Newtonian behavior and suspended particles are modeled by rigid spheres or sticks. This suspension is appropriate for composites injection molding. Our goal is to better understand the rheological behavior of such a mixture under a shear flow. So we consider the evolution of this mixture in a cubic cell, under a shear flow, with pseudo-periodic boundary conditions. We extend the velocity-pressure equations to solid domain by adding a rigid constraint. Thus we obtain a system of velocity-pressure equations defined on the whole fictitious domain that we solve by a Finite Element method. In this multidomain approach, we have to follow the evolution of the positions of solid particles. The solid domain is represented by a characteristic function. A lagrangian transport is used to update the positions of particles, and the corresponding characteristic function is deduced at any time thanks to a Level-Set method. A collision algorithm is used after this transport to correct positions and prevent particles from interpenetrating. Homogenization calculus have been done in order to estimate equivalent viscosity for suspensions of spheres, and behavior laws and models for evolution of orientation tensors in suspensions of fibers. Boundary effects are reduced thanks to pseudo-periodic boundary conditions. Moreover the interface description is improved by a h-adaptation technique. Our results are in rather good agreement with theoretical models, and a first simulation of a 3D mixture flow is presented
Grain, Françoise. "Étude des gènes du complexe majeur d'histocompatibilité : typage d'ovins par la méthode RFLP". Lyon 1, 1994. http://www.theses.fr/1994LYO1T183.
Texto completoTaftaf, Ala. "Développements du modèle adjoint de la différentiation algorithmique destinés aux applications intensives en calcul". Thesis, Université Côte d'Azur (ComUE), 2017. http://www.theses.fr/2017AZUR4001/document.
Texto completoThe adjoint mode of Algorithmic Differentiation (AD) is particularly attractive for computing gradients. However, this mode needs to use the intermediate values of the original simulation in reverse order at a cost that increases with the length of the simulation. AD research looks for strategies to reduce this cost, for instance by taking advantage of the structure of the given program. In this work, we consider on one hand the frequent case of Fixed-Point loops for which several authors have proposed adapted adjoint strategies. Among these strategies, we select the one introduced by B. Christianson. We specify further the selected method and we describe the way we implemented it inside the AD tool Tapenade. Experiments on a medium-size application shows a major reduction of the memory needed to store trajectories. On the other hand, we study checkpointing in the case of MPI parallel programs with point-to-point communications. We propose techniques to apply checkpointing to these programs. We provide proof of correctness of our techniques and we experiment them on representative CFD codes
Bergerat, Lionel. "Développement d’une méthode numérique compressible pour la simulation de la cavitation en géométrie complexe". Thesis, Paris, ENSAM, 2012. http://www.theses.fr/2012ENAM0051/document.
Texto completoCavitation is a phase change phenomenon, wich occurs in low pressure areas in hydraulic systems. Its consequences are often harmful and undesired : it causes loss of efficiency, noise and vibration generation, and structural abrasion... These effects become a major preoccupation in the conception of hydraulic systems. The main objective of this work is to develop a numerical tool for the numerical modelisation of cavitation at high orders of accuracy, for compressible and viscous flows, in complex geometries. The model used for the modelisation of the cavitation is the homogeneous mixture model, wich formulation is independent of empirical parameters, and is easily extendable for multi-spieces flows. We use a finite volume developped in the DynFluid laboratory, in wich the high accuracy order of reconstruction is obtained using the Moving Least Square approximation
Roux, Anthony. "Modélisation par la Méthode des Eléments Discrets de la Déchirure du Complexe Musculo-Tendineux". Thesis, Paris, ENSAM, 2016. http://www.theses.fr/2016ENAM0023/document.
Texto completoTearing of the muscle-tendon complex is a common sport-related injury for athletes. Many studies reported description of this traumatism but mechanisms leading to such an injury are still unclear as are the site of mechanical failure and involved structures. The aim of the thesis is to describe the phenomenon of the muscle-tendon-complex’s tear using the discrete element method and validating the numerical model with experimental data. In the first part, a literature review explains the different properties of the muscle-tendon complex main components’ in order to model it at the macroscopic scale. In the second part, the muscle-tendon complex is modeled. Validation of the mechanical behavior in passive tensile test is proposed by comparison with experimental data from L.-L. Gras on human sternocleidomastodeus muscle. Then, the different influences of morphometric parameters on the mechanical behavior of the complex are investigated. The third part focuses on the rupture. A model of the complex set of {Achilles tendon/surae triceps} is built and a tensile test until rupture is applied. Model validity is assessed by comparison with in vitro experiments from human cadavers. The fourth part focuses on the muscular activation, implemented inside fibers’ behavior. Validity of its active behavior is investigated. This fifth and last presents the enrichment with destructive tensile test. This added test allows first to study the feasibility to model the tear with the discrete element method; and second to focus on damaged structures and rupture’s mechanisms. This offers possibilities for clinical applications of this model to understand and prevent injuries caused by a tear of the muscle-tendon complex
Belkacemi, Yacine. "Méthode des discontinuités de déplacement en champ complexe. Développements analytiques et numériques : application aux milieux fissurés". Lille 1, 1990. http://www.theses.fr/1990LIL10177.
Texto completoM'Boudi, Job. "Aide à la modélisation thermique des systèmes à géométrie complexe associant maillage polygonal et méthode nodale". Poitiers, 1996. http://www.theses.fr/1996POIT2311.
Texto completoEn-Nefkhaoui, Hakim. "Simulation numérique d'un écoulement visqueux incompressible dans une géometrie complexe par la méthode des matrices d'interpolation". Lille 1, 1994. http://www.theses.fr/1994LIL10055.
Texto completoTahiri, M'Hamed. "Méthode d'estimation de l'attracteur et du domaine d'attraction associé pour un processus complexe continu localement instable". Lille 1, 1990. http://www.theses.fr/1990LIL10073.
Texto completoMortazavi, Iraj. "Méthode hybride vortex-éléments finis : étude de la convergence numérique, caractérisation et analyse d'un écoulement complexe". Lille 1, 1997. http://www.theses.fr/1997LIL10090.
Texto completoJARDIN, ANNE. "Etude des sous-sols a structure complexe par interpretation sismique integree". Paris 6, 1993. http://www.theses.fr/1993PA066389.
Texto completoDuprey, Sonia. "Modélisation en éléments finis du complexe de l'épaule et simulation de sa réponse à un choc latéral". Lyon, INSA, 2007. http://theses.insa-lyon.fr/publication/2007ISAL0013/these.pdf.
Texto completoLes traumatismes de l’épaule subis lors d’accidents automobiles, et plus particulièrement lors de chocs automobiles latéraux, ne nuisent généralement pas à la survie des passagers automobiles mais ils provoquent des séquelles à long terme. L’épaule est au premier plan lors d’un choc latéral et les sollicitations transmises au thorax ainsi que la cinématique de la victime dépendent de la réponse au choc de cette articulation. Ainsi, l’objectif de cette étude est d’obtenir un modèle en éléments finis permettant de simuler le comportement dynamique de l’épaule et d’évaluer les risques de blessures en cas de choc latéral. Des essais dynamiques sur clavicule et humérus ont été réalisés. Ces tests ont permis d’étudier la résistance et les paramètres de rupture de ces os et ont permis l’obtention de corridors expérimentaux nécessaires à la validation de modèles éléments finis de ces os. Dans un deuxième temps, des simulations de ces essais expérimentaux ont permis l’évaluation de l’influence de la géométrie de ces os sur leurs réponses sous chargement dynamique jusqu’à rupture et de la nécessité d’une personnalisation géométrique de ces os. Par la suite, l’épaule du modèle numérique HUMOS a été améliorée et validée à l’aide d’essais expérimentaux de choc latéral sur l’épaule, réalisés précédemment au LBMH. Finalement, des simulations ont été réalisées avec un modèle géométriquement personnalisé afin d’évaluer l’influence d’une telle personnalisation. Ainsi, cette étude fournit des données expérimentales concernant les os de l’épaule. De plus, l’influence et la nécessité d’une personnalisation géométrique sont étudiées. Le modèle développé ici est une première avancée vers un outil prédictif pour l’évaluation des risques lésionnels du complexe de l’épaule
Larcher, Nicolas. "Contribution à la caractérisation des matériaux au comportement viscoélastique par méthode ultrasonore : application aux matériaux bitumineux". Limoges, 2014. https://aurore.unilim.fr/theses/nxfile/default/4c5e3d35-135f-4f27-ba5b-d15f37e910cf/blobholder:0/2014LIMO4006.pdf.
Texto completoThis work deals with a laboratory test applied to the thermo viscoelastic materials in particular the bituminous materials. Today, the mechanical characterization of the bituminous materials is very expensive in time, material and equipment. The aim of this study is to propose an alternative to the mechanical test by a Non Destructive Test (NDT) based on ultrasonic wave measurements. The materials of this study, a binder and two asphalt concretes, have been developed by Eiffage Travaux Publics company. These asphalt concretes are otherwise to improve the mechanical properties by an optimization the granular skeleton of the bituminous materials. This study focuses to the different methods of determination of the acoustic parameters like velocity and attenuation factor. Moreover, their frequency dependence is highlighted. Experimental data, obtained with the standard mechanical modulus test, have been taking into account as the reference and plotted in term of master curves and complex representations as Cole – Cole and Black spaces. A rheological model (2S2P1D) which has a continuum spectrum, is fitted to the mechanical representation. The ultrasonic characterization of the materials is based on two aspects : on one side the determination of phase velocity and attenuation factor of compression and shear waves, on the other side the theory of 2D wave propagation in elastic and viscoelastic medium which allows to determining mechanical properties (G*, E*, v*). A good agreement is showed between the ultrasonic data, the mechanical characterization and the rheological prediction. The complex representations which are based on the expression of real and imaginary parts of the complex modulus and the phase angle, are the major contribution of the hypothesis of wave propagation in a viscoelastic medium for the utilization
Bohnke, Claude. "Application de la méthode des diagrammes d'impédance complexe à l'étude de couches minces électrochromes de trioxydes de Tungstène". Besançon, 1986. http://www.theses.fr/1986BESA2012.
Texto completoDeplus, Christine. "Comportement mécanique de la lithosphère océanique : cas d'une subduction complexe". Paris 11, 1987. http://www.theses.fr/1987PA112507.
Texto completoAllain, François. "Nouvelle méthode d’interprétation de données de spectrométrie de masse en tandem pour l’identification de microorganismes dans un échantillon complexe". Thesis, Rouen, INSA, 2014. http://www.theses.fr/2014ISAM0010.
Texto completoThe rapid identification of the microbial content of a complex biological sample is a major issue in biodefense and in areas related to human health, biotechnology and the environment. Tandem mass spectrometry (MS/MS) enables accurate profiling of the protein content of a sample. This thesis focuses on the development of a new concept in MS/MS data interpretation to identify the microbial content of a sample using general protein databases without prior knowledge of the target. The identification approach is based on (i) the most extensive protein database currently available and (ii) an MS/MS spectra interpretation algorithm. A dedicated computer architecture has been developed to combine the MS/MS results according to the taxonomy of living organisms while minimizing the required processing time and maximizing the MS/MS spectra assignment rate. A recursive identification strategy across the taxonomic tree based on the number of specific spectra associated with each taxon is possible but does not confidently identify the contents of a sample containing multiple sequenced organisms. The innovative concept developed here enables the correlation of the number of spectra assigned to a given taxon and the phylogenetic distances between this taxon and the taxon of the organism present in the case of a sample containing a single sequenced organism. This correlation allows us to model and determine the presence of any sequenced organism in a sample containing multiple organisms. An automatic tool for estimating phylogenetic distances between taxa has been developed. This tool is based on the addition of new organisms to a multiple sequence alignment comprising 31 families of universal proteins from organisms from all 3 domains of life (Bacteria, Archaea, Eukarya). Finally, two algorithms for identifying multiple organisms from a single sample have been assessed : a naive greedy algorithm based on a heuristic and an iterative algorithm that solves a non-convex optimization problem using a weighted ℓ1 norm regularization term
Akoussan, Komlan. "Modélisation et conception de structures composites viscoélastiques à haut pouvoir amortissant". Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0188/document.
Texto completoModeling and design of composite viscoelastic structures with high damping powerThe aim of this thesis is to develop numerical tools to determine accurately damping properties of composite sandwich structures for the design of lightweight viscoelastic sandwichs structures with high damping power. In a first step, we developed a generic tool implemented in Matlab for determining damping properties in free vibration of viscoelastic sandwich plates with laminate faces composed of multilayers. The advantage of this tool, which is based on a finite element formulation, is its ability to take into account the anisotropy of composite layers, the material non-linearity of the viscoelastic core induiced by the frequency-dependent viscoelastic laws and various boundary conditions . The nonlinear complex eigenvalues problem is solved by coupling homotopy technic, asymptotic numerical method and automatic differentiation. Then for the continuous study of a modeling parameter on damping properties of viscoelastic sandwichs, we proposed a generic method to solve the nonlinear residual complex eigenvalues problem which has in addition to the frequency dependence introduced by the viscoelastic core, a modeling parameter dependence that describes a very specific study interval. This resolution is based on asymptotic numerical method, automatic differentiation, homotopy technique and continuation technic and takes into account various viscoelastic laws. We propose after that, two separate formulations to study effects on the damping properties according to two modeling parameters which are important in the design of high viscoelastic sandwichs with high damping power. The first is laminate fibers orientation in the sandwich reference and the second is layers thickness which when they are well defined allow to obtain not only sandwich structures with high damping power but also very light. The highly nonlinear complex eigenvalues problems obtained in these formulations are solved by the new method of resolution of eigenvalue residual problem with two nonlinearity developed before. Comparisons with discrete results and computation time are made to show the usefulness of these two formulations and of the new method of solving nonlinear complex eigenvalues residual problem of two dependances
Mehri, Fariba. "Étude d'une méthode de mesure de la conductivité complexe en microondes de films minces supraconducteurs à haute température critique". Lille 1, 1994. http://www.theses.fr/1994LIL10118.
Texto completoBoussatour, Ghizlane. "Caractérisation diélectrique et thermique de films biopolymères pour l’électronique flexible haute fréquence". Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1I015/document.
Texto completoBiopolymer materials attract significant attention in many fields where they tend to replace petrosourced polymers. Thanks to their properties, such as biocompatibility, biodegradability, flexibility and lightness, biopolmyers are also increasingly used in many electronic applications. Nevertheless, their possible integration into high-frequency electronics requires the study of important properties such as thermal conductivity and dielectric complex permittivity. In this work we are interested in two biopolymers in particular, poly lactic acid (PLA) and cellulose palmitate (CP). The extraction of the properties of these materials is carried out through the implementation of two methods. The means selected are the 3ω method for the thermal conductivity and the two-line method for the dielectric complex permittivity. This latter is measured in the frequency band 0.5 - 67 GHz. These two characterization techniques require the realization of metal lines on the surface of the biopolymer films. Since biopolymers are not compatible with classical photolithography method, an alternative processes have been developed to meet this technological challenge. This experimental work is accompanied by modeling studies on both aspects, estimates of the thermal conductivity and the complex dielectric permittivity of the investigated materials. The comparison of the proposed analytical and numerical models with the experimental data shows a good understanding of the problem of characterization of these biopolymers
Romeo, Silvia. "La construction de la représentation d'action complexe au cours du développement par la médiation des langues italienne et française : étude longitudinale". Paris 10, 2001. http://www.theses.fr/2001PA100073.
Texto completoThis longitudinal research, based on the natural discourse of an Italian French bilingual child in family interactions, follows a developmental, interactional perspective and a conceptual approach. Analysis is based on linguistic data taken from daily situations. Cognitif and linguistic development are considered in terms of the contribution of the coexisting Italian and French linguistic systems. We have considered language acquisition by the mediation of two first languages for the construction of the representation of complex actions, taken as integrating the notional fields of temporality , causal and goal relations. Two developmental stages are considered : from 2 to 3;3 and from 3;4 to 4;9. At the first stage we see the gradual construction of the semantic roles of agent, patient, and instrument and of the categories of state, action and event as related to temporal, causal and goal relations. These relations develop in the second stage "transformational system" organisations. First stage results confirm the general hypothesis that the acquisition of two first languages is a semantic and formal factor of organisation, as based on a more complex anchoring points than first language acquisition. Second stage results show that child productions, as linearization of hierarchical series of actions of a high degree of temporal granularity, reveal an on line planification, as founded on a scheme of complex action representation. We have taken into consideration the role of two first languages in the organisation of knowledge and the way of structuring it
Baulac, Marine. "Optimisation des protections anti-bruit routières de forme complexe". Phd thesis, Université du Maine, 2006. http://tel.archives-ouvertes.fr/tel-00415879.
Texto completoActuellement, le choix des protections anti-bruit se porte souvent sur des solutions triviales ou issues d'études paramétriques. Or le CSTB possède des codes de calculs numériques avancés dédiés à la simulation de la propagation acoustique en milieu extérieur. Le but de cette thèse est de coupler ces codes prévisionnels avec un outil mathématique à développer permettant une recherche systématique des solutions optimales.
Une étude bibliographique a permis de dégager des algorithmes applicables au cas de l'optimisation de paramètres caractérisant un écran acoustique. Ils ont été appliqués avec succès aux écrans multi-diffracteurs. Des méthodes d'optimisation multiobjectif ont en outre permis d'optimiser simultanément le prix de revient de la protection et son efficacité acoustique. Dans une optique de développement durable, un travail a été réalisé sur l'efficacité de protections acoustiques de faible hauteur en milieu urbain dans le but de créer des espaces calmes. Des mesures sur modèles réduits ont été confrontées aux simulations acoustiques et l'optimisation de la forme de ces protections a permis de dégager des solutions optimales. Enfin, les méthodes d'optimisation ont été appliquées au cas de l'optimisation de trajectoires.
Les principaux objectifs de la thèse ont été atteints, notamment par la création d'un outil utilisant des algorithmes d'optimisation (Nelder Mead et Algorithmes Génétiques) ainsi que les codes de calculs de simulation acoustique en milieu extérieur.
Zapata, Laurence. "Approche d'une méthode de cyclisation d'oligonucléotides par l'intermédiaire de complexes des métaux de transition". Toulouse 3, 2002. http://www.theses.fr/2002TOU30069.
Texto completoLe, Hardy David. "Traitement des conditions aux limites spéculaires pour l'étude du transfert radiatif dans des matériaux à géométrie complexe". Thesis, Nantes, 2017. http://www.theses.fr/2017NANT4016/document.
Texto completoThis dissertation considers the development of numerical tools for the solution of the radiative transfer equation within threedimensional media with complex geometries, combined with the accurate treatment of specular boundary conditions. Numerical developments rely on the Discrete Ordinate Method, combined with SUPG-type stabilized Finite Elements. A very novel partitioning method has been developped for accurate treatment of specularity on borders. Also, some Gauss– Seidel type and GMRES parallel solvers have been used to deal with huge size matrix systems, due to fine discretization in both space and angles, needed for such considered geometrical complexity. Finally, all developped numerical tools have been tested for the modelling of radiative transport within a micro-tomographied ceramic ligament, extracted from a real open-cell foam
Licir, Ismaïl. "Étude des champs diffractés par des matériaux à pertes et reconstitution de la permittivité diélectrique complexe". Toulouse, INPT, 1997. http://www.theses.fr/1997INPT064H.
Texto completoOrti, Rachel. "Radiosité dynamique 2D et complexe de visibilité". Phd thesis, Université Joseph Fourier (Grenoble), 1997. http://tel.archives-ouvertes.fr/tel-00004958.
Texto completoSzalek, Aline. "Modélisation de formes complexes : proposition d'une méthode de raccordement par déformation de carreaux jointifs". Nancy 1, 1993. http://www.theses.fr/1993NAN10027.
Texto completoKlonk, Steffen. "Modélisation numérique du chauffage par induction de pièces à géométrie complexe". Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 2013. http://pastel.archives-ouvertes.fr/pastel-00982312.
Texto completoAzzabi, Lotfi. "Contribution à l'amélioration d'un système de production : intégration de la méthode six sigma et approche multicritère d'aide à la décision dans Sidelec Internationale". Angers, 2010. http://www.theses.fr/2010ANGE0064.
Texto completoFor several years, the context of globalization and increased competition have defined a new economic and industrial companies for production of goods. Indeed, these companies are confronted daily with the control and performance enhancement of all their processes to ensure their sustainability and competitiveness. Due to the opening of markets and increased competition, several concurrent phenomena occur. Firstly, the phenomenon most notable clients' expectations more and more strong, not only regarding the price and quality, but also on innovation of products and their availability. In such situations we propose to follow the variability of the process through the integration of Six Sigma, to detect evidence of significant change in variability. The main objective of Six Sigma is to increase profitability by reducing waste, while having the client's interest at heart. It is a statistical measure of process performance that can determine with precision the quality of products or services. Six Sigma is a management system that grows the fastest in the industry today. Centered on a powerful problem solving methodology and process optimization. The Power of Six Sigma is the application of statistical tools in the context of a structured and easy to implement. These tools, used most often in an operational environment of production, also apply to all processes, including administrative. The aim of our research is to provide an operational vision, structured through the integration of Six Sigma tools based multicriteria decision support to improve a production system, this translates to understand and know how to optimize production processes in order to reduce the number of defects and process variability. The proposed methodology is applied to society SIDILEC International specializes in the manufacture of electrical wiring harnesses for the manufacturers of cars with and without a license. The automotive industry is changing at a speed of more and more important. Indeed, the rapidly changing techniques and technologies along with an explosion of information technology, has put companies face fierce competition. Faced with this situation, the company must strive to turn the search for a better approach to enable it to achieve the desired level of competitiveness and customer satisfaction. The work takes place in a production facility that specializes in the design and manufacture of electric wiring harnesses for automotive and railway industries. Upon completion of this work, we consider that our objectives identified in the theoretical support are well made and justified under this chapter practice. The integration of Six Sigma tools based on multicriteria decision support to improve a production process is completely accomplished and that means understanding and knowing how to improve a production process in order to reduce the number of defects and process variability
Dainese, Marie-Pierre. "Simulation d'écoulements de fluide compressible en géométrie complexe : contribution à l'étude des schémas de discrétisation et d'algorithmes semi-implicites". Toulouse, ENSAE, 1994. http://www.theses.fr/1994ESAE0016.
Texto completoBollérot, Karine. "Emergence de précurseurs hématopoïétiques chez l' embryon d' oiseau : nouvelle méthode d' étude fonctionnelle in vivo : implication du complexe transcriptionnel RUNX1/CBFβ". Paris 6, 2005. http://www.theses.fr/2005PA066271.
Texto completoChupin, Marie. "Segmentation automatique du complexe hippocampe-amygdale à partir de données d'imagerie par résonance magnétique : application à des cas cliniques et à la modélisation de sources en magnéto/électro-encéphalographie". Paris 11, 2004. http://www.theses.fr/2004PA112126.
Texto completoTemporo-medial structures, the hippocampus and the amygdala play a major role in essential cognitive processes and may be damaged in epilepsy and Alzheimer's disease. Their study through manual segmentation on anatomical images (Magnetic Resonance Imaging) is long and poorly repeatable, which makes automatic segmentation an important goalBased on 3D region growing, the automatic segmentation we propose here is guided by the minimisation of an energy, which is made of five terms: two data attachment terms (global and local), and three regularisation terms (regularity, volume and surface). The two objects, initialised by two seeds (one by object), deform independently until they meet, the competition being considered then. The deformation is further constrained by priors based on stable anatomical characteristics. The segmentation is qualitatively and quantitatively validated for 8 young healthy subjects, by comparing two manual and one automatic segmentations. An application of this method for structures' volumetry in Alzheimer's disease was done. The comparison of automatic and manual segmentations in 4 patients showed that this tool could add crucial information in the study of this disease. This method was also considered for 4 epileptic patients with hippocampal sclerosis, and the first results are correct. Finally, the segmentation's results are used in source modelling for Magneto/ElectroEncephaloGraphy, in order to discriminate the signal created by hippocampal sources from the cortical one, through correlation analysis
Cimetière, Jacqmin Anne. "MMéthodes temporelles et temps-fréquence pour la reconnaissance automatique des complexes K de l'électroencéphalogramme du sommeil". Compiègne, 1997. http://www.theses.fr/1997COMP1006.
Texto completoAuliac, Sylvain. "développement d'outils d'optimisation pour freefem++". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2014. http://tel.archives-ouvertes.fr/tel-01001631.
Texto completoNana, Ngassam Valéry. "Collisions électrons-ions moléculaires : états résonnants et dynamique de dissociation". Paris 11, 2004. http://www.theses.fr/2004PA112284.
Texto completoDissociative recombination and related processes are specially effective in interstellar media where the very low density and temperature favour exothermic reactions. They also play an important role in various types of “cold” plasmas. This work reports the study of dissociative recombination of H2+, Ne2+ and HCNH+ molecular ions. The molecular states and their mutual interactions (for Ne2+ + e- and HCNH+ + e- systems) are calculated by ab initio methods: CI calculations for the bound part of the energy spectrum and electron-molecule scattering within the framework of the complex Kohn variational method for the continuous part. The low-energy dynamics (H2+ et Ne2+) is then treated by the multichannel quantum defect method. Several extensions of the formalism were developed in order to take account of the “off the energy shell” effects and to explicitly include the non-adiabatic couplings of the Rydberg states open to dissociation either between them or with the ion continuum
Cisonni, Julien. "Modélisation et inversion d'un système complexe de production de signaux acoustiques : application à la voix et aux pathologies". Phd thesis, Grenoble INPG, 2008. http://www.theses.fr/2008INPG0103.
Texto completoPhysical modeling of phonation intends to explain and reproduce the phenomena occurring during the vocal folds oscillations, which generate the acoustical signal of the voiced sounds of speech. This thesis proposes at first an experimental study and the modeling of the influence of different mechanical, geometrical and acoustical conditions on the oscillations properties of vocal folds deformable replicas. A particular attention is then paid to the glottal flow modeling. The inversion of one-dimensional models is used to estimate quantities generally considered as input/control parameters. A 2D laminar flow model based on the finite element method is implemented in order to describe more precisely the glottal flow. Flow models predictions are compared to in-vitro measurements performed on vocal folds rigid replicas for several conditions
Cisonni, Julien. "Modélisation et inversion d'un système complexe de production de signaux acoustiques : application à la voix et aux pathologies". Phd thesis, Grenoble INPG, 2008. http://tel.archives-ouvertes.fr/tel-00363714.
Texto completoMargueritte, Laure. "Développement d’une méthode de déconvolution pharmacophorique pour la découverte accélérée d’antipaludiques chez les Rhodophytes". Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAF048/document.
Texto completoMalaria is responsible for 445 000 deaths in 2016. The emergence and the spread of resistant P. falciparum to artemisinin-based combinations is a major health problem in South-East Asia. Research must continue to find compounds with a novel mechanism of action. The apicoplast is an interesting target. It is a Plasmodium organelle derived from a secondary endosymbiosis with a red alga. Red algae could be a special source of new antiplasmodial compounds targeting the isoprenoid biosynthesis pathway in the apicoplast. This thesis focuses on bioactive secondary metabolites identification via a new analytical strategy. A computer program called Plasmodesma was created and achieves an automatic differential analysis of 1H-1H and 1H-13C 2D NMR spectra. Bioactive compounds are isolated and identified by hyphenated HPLC-SPE-NMR. The presence of different classes of compounds including sterols could explain the antiplasmodial activity in studied the red algae species
Boulanger, Benoît. "Synthèse en flux et étude des propriétés optiques cristallines linéaires et non linéaires par la méthode de la sphère de KTiOPO et des nouveaux composés isotypes et solutions solides de formule générale (K, RB, CS) TIO (P,AS) O4". Nancy 1, 1989. http://www.theses.fr/1989NAN10043.
Texto completoPeynaud, Emilie. "Rayonnement sonore dans un écoulement subsonique complexe en régime harmonique : analyse et simulation numérique du couplage entre les phénomènes acoustiques et hydrodynamiques". Thesis, Toulouse, INSA, 2013. http://www.theses.fr/2013ISAT0019/document.
Texto completoThis thesis deals with the numerical simulation of time harmonic acoustic propagation in an arbitrary mean flow in an unbounded domain. Our approach is based on an equation equivalent to the linearized Euler equations called the Galbrun equation. It is derived from a mixed Eulerian-Lagrangian formulation and results in a single equation whose only unknown is the perturbation of the Lagrangian displacement. A direct solution using finite elements is unstable but this difficulty can be overcome by using an augmented equation which is constructed by adding a new unknown, the vorticity, defined as the curl of the displacement. This leads to a set of equations coupling a wave like equation with a time harmonic transport equation which allows the use of perfectly matched layers (PML) at artificial boundaries to bound the computational domain. The first part of the thesis is a study of the time harmonic transport equation and its approximation by means of a discontinuous Galerkin scheme, the difficulties coming from the oscillating behaviour of its solutions. Once these difficulties have been overcome, it is possible to deal with the resolution of the acoustic propagation problem. The approximation method is based on a mixed continuous-Galerkin and discontinuous-Galerkin finite element scheme. The well-posedness of both the continuous and discrete problems is established and the convergence of the approximation under some mean flow conditions is proved. Finally a numerical implementation is achieved and numerical results are given which confirm the validity of the method and also show that it is relevant in complex cases, even for unstable flows
Joan, Michaël. "Modélisation des paramètres R et L de matériels électriques bobinés par la méthode des éléments finis 3D". Phd thesis, Grenoble INPG, 2004. http://tel.archives-ouvertes.fr/tel-00408300.
Texto completoLe travail réalisé a consisté à développer une méthode permettant de s'affranchir du calcul des courants de Foucault par éléments finis. Cela a abouti au concept de perméabilité magnétique complexe. Par l'utilisation d'une formulation en potentiel scalaire magnétique et de la perméabilité complexe il a été possible de mettre en place une méthode de détermination des parmètres caractéristiques d'un transformateur de puissance. Paramètres sous forme matricielle qui seront utilisés pour des simulations de réseaux électriques.
Bayh, Omar. "Nouvelle méthode de fonctionnalisation d'hétérocycles et des composés benzéniques par voie organimétallique : déprotonations par des magnésiates, réactions avec des électrophiles et couplages". Thesis, Rouen, INSA, 2008. http://www.theses.fr/2008ISAM0010.
Texto completoThis present work reports the development of a novel versatile aromatic functionnalization methodology based upon deprotonation with magnesiate bases (lithium alkyl- and /or amidomagnesiates) at room temperature, currently poorly studied and the use of the novel arylmagnesiates complexes formed as nucleophilic agents and organometallic partners in the cross-coupling reaction. The deprotonation of the five-membered heterocycles (furan, thiophene, benzoxazole and oxazole) was first successfully accomplished using mainly Bu3MgLi as base. The arylmagnesiates thus obtained, including the expected ring-opened magnesiate complexes obtained from deprotonation of benzoxazole and oxazole, proved to be effective in several reactions as deuteration, halogenation, silylation and nucleophilic addition on aromatic aldehydes leading to the corresponding substituted heterocycles. Futhermore the heteroarylmagnesiates complexes revealed to be efficient in cross-coupling reaction with bromo(hetero)aromatics catalyzed by PdCl2(dppf). In a second part, works were directed toward the study of the ortho-functionnalization of benzene derivatives. Thus, the deprotonation of oxazolyl-, carboxamido-, pivaloylamino- and methoxybenzenes as well as benzene sulfoxyde was achieved using mainly (di)lithium tri(tetra)magnesiate bases. The arylmagnesiates complexes showed a good nucleophilic reactivity toward deuterative, halogenative and silylative agents and methyloxirane whereas reactions with aromatic aldehydes occurred in more moderate yields due to two side processes, addition of a butyle group and reduction of the aldehyde function. The arylmagnesiates excepted from benzene sulfoxyde could be coupled with bromo(hetero)aromatics under PdCl2(dppf)-catalysis. In summary, the novel aromatic functionnalization based upon the use of magnesiate bases proved to be particularly efficient and represents many advantages compared to classical methods such as metalation at room temperature for direct industrial application as well as the use of a new class of organometallic reagents possessing a good nucleophilic reactivity and directly valuable in the transition metal-catalyzed cross-coupling reaction
Nguyen, Kim Anh. "Développement de stratégies de maintenance prévisionnelle de systèmes multi-composants avec structure complexe". Thesis, Troyes, 2015. http://www.theses.fr/2015TROY0027/document.
Texto completoToday, industrial systems become more and more complex. The complexity is due partly to the structure of the system that cannot be reduced to classic structure reliability (series structures, parallel structures, series-parallel structures, etc), secondly the consideration of components with gradual degradation phenomena that can be monitored. This leads to the main purpose of this thesis on the development of predictive maintenance strategies for complex multi-component systems. The proposed policies provide maintenance grouping strategies to take advantage of the economic dependence between components. The predictive reliability of components and importance measures allowing taking into account the structure of the system and economic dependence are developed to construct the grouping decision rules. Moreover, a joint decision rule for maintenance and spare parts provisioning is also studied.All the conducted studies show the interest in the consideration of the predictive reliability of components, economic dependencies as well as complex structure of the system in maintenance decisions and spare parts provisioning. The advantage of the developed strategies is confirmed by comparing with the other existing strategies in the literature
Semail, Eric. "OUTILS ET MÉTHODOLOGIE D'ÉTUDE DES SYSTÈMES ÉLECTRIQUES POLYPHASÉS. GÉNÉRALISATION DE LA MÉTHODE DES VECTEURS D'ESPACE". Phd thesis, Université des Sciences et Technologie de Lille - Lille I, 2000. http://tel.archives-ouvertes.fr/tel-00266256.
Texto completoTout d'abord, on caractérise les modulateurs d'énergie indépendamment de leurs charges. Pour cela des espaces vectoriels leur sont associés ainsi que des familles de vecteurs qui les caractérisent. Il est possible alors de définir quel type de charge le modulateur est capable de contrôler. Les degrés de liberté de la commande trouvent également une formulation mathématique. Les exemples traités sont les onduleurs de tension monophasé et triphasé deux niveaux. L'approche conduit, dans le cas d'une commande aux valeurs moyennes, à un calcul original des durées de conduction des interrupteurs en utilisant la notion de barycentre. Les algorithmes obtenus, généralisables aux onduleurs à n bras, comportent un nombre réduit d'opérations logiques et arithmétiques.
Le formalisme est ensuite appliqué à la machine asynchrone triphasée avec q barres au rotor ; ceci nous permet d'expliciter la notion de rotor diphasé équivalent. La machine asynchrone pentaphasée est également modélisée et l'approche développée met en évidence les conditions que doit remplir l'onduleur à 5 bras pour l'alimenter correctement.
Dans la dernière partie, un onduleur de courant à Modulation de Largeur d'Impulsions est étudié à l'aide du formalisme. Les non-linéarités de la commande sont prises en compte vectoriellement, notamment, de façon originale, celle concernant la durée minimale de conduction des interrupteurs. On décrit enfin l'implantation matérielle de cette commande sur microcontrôleur 16 bits et présente les résultats expérimentaux dans le cas d'une charge constituée d'une machine asynchrone triphasée en parallèle avec des condensateurs.
Delavaud, Elise. "Simulation numérique de la propagation d'ondes en milieu géologique complexe : application à l'évaluation de la réponse sismique du bassin de Caracas (Venezuela)". Paris, Institut de physique du globe, 2007. http://www.theses.fr/2007GLOB0010.
Texto completoNguyen, Minh-Duc. "Modélisation numérique discrète des matériaux bitumeux". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSET003/document.
Texto completoBituminous mixtures have traditionally been used in road constructions and recently under railway ballast. Its high rigidity at relatively low ambient temperatures and high frequency explains its widespread application in northern Europe. This material has been studied at the global level by both empirical, experimental and analytical approaches. However, the asphalt has a heterogeneous internal structure and complex which may cause complex behavior. The analysis at the local level then make it possible to supplement the knowledge of its behaviors.Nowadays, the method of discrete elements is known as a numerical tool spread in the granular field. It can model its behavior through local models and provide information about its internal structure. On the one hand, this method considers that the particles are quasi-solid. Its displacement is governed by the laws of motion. On the other hand, the overlap at the particle contact level is allowed. The interpenetration of the particles is calculated by the associated local contact laws. This thesis constitutes a numerical model of bituminous mixes whose isolated particles interact through laws of interaction at a distance. This model takes into account the granulometry of the aggregates (> 1 mm) and its volume ratio with respect to the mastic constituted by grains (<1 mm), the binder and voids. The aggregates (> 1 mm) alone are modeled by numerical particles, while mastic is taken into account by laws of interaction.First, an elastic simulation is performed in order to reproduce the elastic asymptotic behaviors of a reference bituminous mix of GB3 type that appear during extreme conditions (frequency or temperature). Elastic interaction laws have applied to the created numerical model. In both normal and tangential directions, the stiffness of the spring and its ratio are constant.Then, the viscoelastic simulations are performed to reproduce the viscoelastic behavior of the same reference material. At first, a Kelvin-Voigt interaction law is used to qualitatively highlight the application of a viscoelastic law. Then, the global viscoelastic behavior is modeled at the level of the particles by some laws of interaction of type 1KV1R (a Kelvin-Voigt and a spring in series) leaving again to the network of interaction of the numerical model. The stiffness of the springs taking into account the geometry of the particle interface is constant for all models of 1KV1R. However, the viscosities of the dashpots are different. Some hypotheses are examined to distribute its viscosities in the interaction network. At the end of the studies, the analysis of the internal efforts are carried out