Rozprawy doktorskie na temat „Densité de puissance absorbée”
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Jafari, Seyedfaraz. "Near-field millimeter-wave radio-frequency exposure analysis". Electronic Thesis or Diss., Institut polytechnique de Paris, 2023. http://www.theses.fr/2023IPPAT034.
Pełny tekst źródłaThis thesis aims to determine the absorbed power density (APD) considering the coupling and multiple reflections between the antenna and the human body, which poses challenges in assessing APD due to their close proximity.The first part of the thesis explores the concept of measuring APD inside a skin tissue phantom, specifically focusing on its application in 5G technologies.However, measuring APD inside the skin tissue phantom is limited due to the shallow penetration depth of fields at millimeter and quasi-millimeter waves. To overcome this limitation, a reconstruction technique is employed, utilizing the backward plane-wave spectrum(PWS) method. The electric field is sampled at a specific distance within the phantom, enabling the determination of APD at the human skin surface.In the second part, a non-invasive approach based on the dyadic Green's function (DGF) is proposed for APD assessment. This method takes into account the coupling between the human skin model and the device under test (DUT). The entire space is dividedinto two half-spaces : the upper half-space (z > 0) is filled with air, where the antenna is positioned, and the lower half-space is filled with an equivalent human skin liquid or solid. The electric field integral equation (EFIE), based on spatial DGFs, is solved using the method of moments (MoM) to reconstruct the equivalent currents. The electric field is sampled on the surface of a hemisphere surrounding the antenna, and the APD is evaluated based on the reconstructed equivalent currents beneath the air-phantom interface.In addition to the proposed techniques, the thesis investigates the measurement requirements for both approaches, including E-field measurement uncertainty, sampling angular resolution, and the required size of the phantom.The findings demonstrate that the proposed techniques present a novel methodology for assessing APD, taking into consideration the coupling between the human body and the antenna, particularly in the context of exposure to handheld devices operating above 6GHz
Bendjebara, Naïla. "Evaluation et caractérisation statistique de la puissance absorbée par la tête d'un utilisateur sujet au rayonnement radiofréquence d'un téléphone mobile". Paris 6, 2002. http://www.theses.fr/2002PA066033.
Pełny tekst źródłaMohamed, Massoud Abdelaal Magdy. "Modélisation et caractérisation de la densité de puissance électromagnétique déposée dans des charges mobiles". Toulouse, INPT, 1999. http://www.theses.fr/1999INPT022H.
Pełny tekst źródłaEssadaoui, Jamila. "Commande d'un onduleur de puissance destiné au chauffage par induction par la modulation de densité d'impulsion avec amélioration du facteur de puissance". Thèse, Université du Québec à Trois-Rivières, 2003. http://depot-e.uqtr.ca/4535/1/000105149.pdf.
Pełny tekst źródłaGeeraert, Nausikaa. "Evaluation quantitative de tissu fibroglandulaire pour l'estimation de l'énergie absorbée différenciée par tissu en tomosynthèse du sein". Thesis, Paris, ENST, 2014. http://www.theses.fr/2014ENST0060/document.
Pełny tekst źródłaIn this research project the main goals were a) to implement a method for the computation of the volumetric breast density (VBD), and b) to propose an improved quantity for the assessment of individual radiation-induced risk, in particular during mammography, together with a method to quantify it. The breast density is known as a breast cancer risk factor. The objective quantification of the volumetric breast density was developed, based on already published methods, and improved. The method was implemented for two mammography systems. It is based on the calibration of the mammography system acquisition chain with breast equivalent phantoms and computes a breast density map. Our most important contribution resides in a new validation method applicable to any VBD computation, consisting in comparing its results with the VBD obtained from a thorax CT examination for the same patient. This validation method was applied to our VBD computation. We found an average deviation between mammography and CT of less than 10%. Our results are comparable to the state-of-the-art results for other validation methods. For the individual radiation risk, we proposed to replace the average glandular dose by the imparted energy, which depends on the quantity and distribution of the glandular tissue, which is the tissue at risk. The volumetric imparted energy is computed from Monte Carlo simulations. The VBD, computed for the 0° projection of tomosynthesis exams, helps us to localize the glandular tissue and to attribute the imparted energy to the different tissues. A proposition was implemented for geometric phantoms, a textured phantom and a patient case
Geeraert, Nausikaa. "Evaluation quantitative de tissu fibroglandulaire pour l'estimation de l'énergie absorbée différenciée par tissu en tomosynthèse du sein". Electronic Thesis or Diss., Paris, ENST, 2014. http://www.theses.fr/2014ENST0060.
Pełny tekst źródłaIn this research project the main goals were a) to implement a method for the computation of the volumetric breast density (VBD), and b) to propose an improved quantity for the assessment of individual radiation-induced risk, in particular during mammography, together with a method to quantify it. The breast density is known as a breast cancer risk factor. The objective quantification of the volumetric breast density was developed, based on already published methods, and improved. The method was implemented for two mammography systems. It is based on the calibration of the mammography system acquisition chain with breast equivalent phantoms and computes a breast density map. Our most important contribution resides in a new validation method applicable to any VBD computation, consisting in comparing its results with the VBD obtained from a thorax CT examination for the same patient. This validation method was applied to our VBD computation. We found an average deviation between mammography and CT of less than 10%. Our results are comparable to the state-of-the-art results for other validation methods. For the individual radiation risk, we proposed to replace the average glandular dose by the imparted energy, which depends on the quantity and distribution of the glandular tissue, which is the tissue at risk. The volumetric imparted energy is computed from Monte Carlo simulations. The VBD, computed for the 0° projection of tomosynthesis exams, helps us to localize the glandular tissue and to attribute the imparted energy to the different tissues. A proposition was implemented for geometric phantoms, a textured phantom and a patient case
Moulin, Cécile. "Élaboration de monocristaux de carbure de silicium pour l’électronique de puissance : réduction de la densité de défauts". Grenoble INPG, 2001. http://www.theses.fr/2001INPG0150.
Pełny tekst źródłaSilicon carbide is a very promising material for high power applications. Today, significant improvements in both SiC wafer size and quality are still necessary to allow a fast development of silicon carbide in Europe. SiC single crystals are grown by a sublimation technique, and still contain several kind of defects usually detrimental for devices applications. A better understanding of the SiC sublimation growth has to be pursued to improve the material quality. First of all, several characterization techniques have been selected to establish relationships between the substrates characteristics and the growth process parameters. Then, a study on the start of growth has been undertaken. It shows that great care must be taken during the initial steps of the growth process in terms of pressure and temperature to avoid the deterioration of the speed surface, and to promote a lateral growth mechanism. This previous work is followed by a study combining growth, characterization and simulation results. The influence of several growth parameters such as the thermal gradients inside the cavity, or the influence of the argon pressure on crystals characteristics is studied and quantified. Results show how the material characteristics are sensitive to small parameters variations, and how it can be deteriorated (polytype switching, droplets…) by minor variations of temperature compared to the working temperatures. An evaluation of the process non-reproducibility, related to this extremely high sensibility of the thermal conditions, is also presented. Then, the structural characteristics of the ingots are studied and the silicon carbide growth mechanism is presented. Finally, first results on the substrate characteristics influence on the diodes electrical performances conclude this work
Mouty, Stéphane. "Conception de machines à aimants permanents à haute densité de couple pour les éoliennes de forte puissance". Thesis, Besançon, 2013. http://www.theses.fr/2013BESA2034/document.
Pełny tekst źródłaGiven the European guidelines, which consist into producing 20% of the energy from renewable sources, the governments are obliged to invest in new types of production systems. An energy market survey will show the part of renewable energy in the energy consumption. After the hydroelectric systems, the wind turbines are the most common systems using renewable sources. The current objectives have led to consider the installation of offshore wind turbine. The specific limitations led the market players to develop new systems with adapted generators: direct drive permanent magnet generator. Model of the permanent magnet machines is described. First a conventional machine topology is presented, then other solutions will be studied with the objective of increasing the torque density. One of them is the concentrated winding machines where the end winding overlapping is avoided. On the other hand, use multiphase system becomes very interesting in order to increase system reliability and work in fault tolerant modes. The strategy that was adopted for the design of the generator to fit the best the specification is also discussed as well as the results of the tests. At the end, the wind turbine equipped with this alternator, has a power density at least 15% higher than the 2013’s available solutions
Lassoued, Salima. "Modélisation de la densité de courant de saturation base-émetteur d'un transistor bipolaire de puissance : effets des forts dopages". Toulouse, INPT, 1992. http://www.theses.fr/1992INPT051H.
Pełny tekst źródłaDerkaoui, Nadira. "Etude des plasmas micro-ondes à haute densité de puissance en systèmes H₂-CH₄ et H₂-CH₄-B₂H₆". Paris 13, 2012. http://scbd-sto.univ-paris13.fr/intranet/edgalilee_th_2012_derkaoui.pdf.
Pełny tekst źródłaThis thesis deals with high power density microwave plasmas of H₂/CH₄and H₂/CH₄ et H₂/CH₄/B₂H₆ mixtures used for growing intrinsic and boron-doped diamond films. The aim of this work is to understand phenomena occurring in the plasma phase and near the plasma/surface interface for high power and high pressure (high power density) in order to overcome the technological limits of the reactors in terms of growth rates for constant quality (in particular purity) and deposition area. This study is based on an approach coupling experiments and modeling that allows, on the one hand the description of the plasma physics and on the other hand, the validation of a 1D model previously developed at LSPM and adapted to the new reactor geometry that has been used for high power density conditions. Evolutions of electron, hydrogen and methyl densities as well as the gas and electronic temperatures are analyzed in relation to process parameters (flow rate, power, pressure, CH₄ %. . . ). Experimental measurements are carried out by actinometry, OES and microwave interferometry and are completed by TALIF. On the whole, comparisons between model and experiments are in good agreement but some limits of the model have been highlighted, e. G. Ionization processes. Moreover, a quasi linear relation has been established between the single diamond growth rate and the hydrogen density of the plasma. Finally, a kinetic scheme for H₂-CH₄-B₂H₆ plasmas is implemented in the 1D model, taking into account 21 reactions and 7 boron containing species, in order to study boron-doped diamond processes
Amegble, Koami Dzigbodi. "Tests non paramétriques de spécification pour densité conditionnelle : application à des modèles de choix discret". Master's thesis, Université Laval, 2015. http://hdl.handle.net/20.500.11794/25773.
Pełny tekst źródłaDans ce travail, nous étudions la performance statistique (taille et puissance) en échantillon fini de deux tests non paramétriques de spécification pour densité conditionnelle proposés par Fan et al. (2006) et Li et Racine (2013). Ces tests permettent de vérifier si les probabilités conditionnelles postulées dans les modèles de choix discret (logit/probit multinomial à effets fixes ou aléatoires, estimateur de Klein et Spady (1993), etc) représentent correctement les choix observés. Par rapport aux tests existants, cette approche a l’avantage d’offrir une forme fonctionnelle flexible alternative au modèle paramétrique lorsque ce dernier se révèle mal spécifié. Ce modèle alternatif est directement issu de la procédure de test et il correspond au modèle non contraint obtenu par des produits de noyaux continus et discrets. Les deux tests explorés ont une puissance en échantillon fini supérieure aux tests existants. Cette performance accrue s’obtient en combinant une procédure bootstrap et l’utilisation de paramètres de lissage des fonctions noyaux par validation croisée par les moindres carrés. Dans notre application, nous parallélisons les calculs de taille et de puissance, ainsi que l’estimation des fenêtres de lissage, sur un serveur multi-processeurs (Colosse, de Calcul Québec). Nous utilisons des routines "Open MPI" pré-implémentées dans R. Par rapport aux simulations effectuées dans les articles originaux, nous postulons des modèles plus proches de ceux habituellement utilisés dans la recherche appliquée (logit et probit à variance unitaire notamment). Les résultats des simulations confirment les bonnes taille et puissance des tests en échantillon fini. Par contre, les gains additionnels de puissance de la statistique lissée proposée par Li et Racine (2013) se révèlent négligeables dans nos simulations. Mots clés : Bootstrap, choix discret, densité conditionnelle, Monte Carlo, produit de noyaux, puissance, taille.
Rémouga, Ylies. "Réponses de structures sur suspensions non-linéaires soumises a des excitations définies par une densité spectrale de puissance : application aux supports d'équipements". Lyon, INSA, 1998. http://www.theses.fr/1998ISAL0049.
Pełny tekst źródłaThe purpose of the thesis deals with the non-linear dynamic behaviour prediction of structures under random excitations. The aim is to calculate the response mechanical system with localized non-linearities, subjected to excitations defined by a power spectral density. This work is about linear structures on suspension mounts which are non-linear especially in deflection. For a given temperature, each mount of the passive suspension is modeled with instantaneous and tangent stiffness’s resulting from experimental quasi-static force-deflection loops. Accelerograms imposed are compatible with PSD from standard on vibration isolation of on-board equipment. The model of linear structure use the finite element method connected to a dynamic condensation procedure. This technique is validated by experiments carried out on ctructure having mounts with low and high damping, and by analytical model. Finally, this procedure is applied on a real on-board equipment
Pimentel, Demian. "Implantation d'un contrôle de puissance pour onduleur à modulation de densité d'impulsions et optimisation des séquences de modulation à l'aide d'algorithmes génétiques". Thèse, Université du Québec à Trois-Rivières, 2006. http://depot-e.uqtr.ca/1523/1/000134644.pdf.
Pełny tekst źródłaRancourt, David. "Analyse structurelle et validation expérimentale d'un Rim-Rotor Rotary Ramjet Engine (R4E)". Mémoire, Université de Sherbrooke, 2011. http://savoirs.usherbrooke.ca/handle/11143/1612.
Pełny tekst źródłaCotoni, Vincent. "Modélisation de phénomènes vibroacoustiques en moyennes et hautes fréquences par méthode énergétique locale". Ecully, Ecole centrale de Lyon, 2001. http://www.theses.fr/2001ECDL0004.
Pełny tekst źródłaThis study describes a local power flow method used for solving vibroacoustic problems. The sound radiation of plane structures and the sound transmission through plane structures are studied and the sound radiation of curved structures is partially investigated. The present approach is dedicated to the middle and high frequency range where the locality principle may be used to calculate a system by solving several local canonical problems encountered in the whole system. The originality of the model is the use of energy quantities such as energy density and power flow. A local power balance is thus derived for each canonical problem. Considering the high frequency assumption that elementary waves describing the vibratory response are uncorrelated, the linear superposition principle is then applied on local energy solutions in order to compute the complete system. Several local energy formulations previously developed and called Méthode Energétique Simplifiée (Simplified Energy Method) are investigated. The particularity of the vibroacoustic coupling is the consideration of diffraction phenomena encountered in power exchanges. Thus, this work is an extension of existing local energy approaches
Goavec, Anthony. "Conception d'un estimateur intégré en technologie CMOS de la densité spectrale de puissance pour l’auto-calibration des émetteurs radio impulsionnels ultra-large bande". Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0052/document.
Pełny tekst źródłaThis thesis focusses on the power emission constraints defined by regulations and standards for every kinds of ultra-wide band impulse radio transmitters. In fact, these power emission constraints have to be respected all along the device life. Also, an integrated sensor able to extract the essential information for an on-chip estimation of the power spectral density has been realized. Then, an embedded algorithm is added to the system and detects if a power limit is broken. If necessary, it acts on the transmitter to solve the problem. In the first chapter, a large variety of power constraints shapes and several architectures of impulse generators have been observed and studied. Therefore, the aim of this thesis is to realise a calibration system which would be universal to all impulse radio transmitters. After its extraction at the output of the transmitter, information have to be downconverted in order to reduce the constraints on conversion stage but without using a local oscillator and a mixer. A model for the impulse signal based on the instantaneous envelop and on the instantaneous frequency has been proposed in the second chapter. A new calibration method based on these two signals is also presented. The last chapter concentrates on detailing the extraction of the instantaneous envelop and the instantaneous frequency. The design of the electronic devices essential to this extraction is presented and a chip has been realised and the viability of the solution shown
Goavec, Anthony. "Conception d'un estimateur intégré en technologie CMOS de la densité spectrale de puissance pour l’auto-calibration des émetteurs radio impulsionnels ultra-large bande". Electronic Thesis or Diss., Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0052.
Pełny tekst źródłaThis thesis focusses on the power emission constraints defined by regulations and standards for every kinds of ultra-wide band impulse radio transmitters. In fact, these power emission constraints have to be respected all along the device life. Also, an integrated sensor able to extract the essential information for an on-chip estimation of the power spectral density has been realized. Then, an embedded algorithm is added to the system and detects if a power limit is broken. If necessary, it acts on the transmitter to solve the problem. In the first chapter, a large variety of power constraints shapes and several architectures of impulse generators have been observed and studied. Therefore, the aim of this thesis is to realise a calibration system which would be universal to all impulse radio transmitters. After its extraction at the output of the transmitter, information have to be downconverted in order to reduce the constraints on conversion stage but without using a local oscillator and a mixer. A model for the impulse signal based on the instantaneous envelop and on the instantaneous frequency has been proposed in the second chapter. A new calibration method based on these two signals is also presented. The last chapter concentrates on detailing the extraction of the instantaneous envelop and the instantaneous frequency. The design of the electronic devices essential to this extraction is presented and a chip has been realised and the viability of the solution shown
Coduti, Giovanni Antonio Coduti. "Etude de l'interaction d'une onde électromagnétique avec un plasma d'air à température ambiante". Paris 11, 2005. http://www.theses.fr/2005PA112016.
Pełny tekst źródłaWe indicate under the name of radar a system which illuminates a portion space with an electromagnetic wave and receives waves reflected by objects which are there. It makes it possible to detect their existence and to determine characteristics of these objects. Measurements of Radar Cross Section (RCS) carried out with ONERA show that the air intake behaves as reflectors which reflect waves radars in their direction of incidence. During this study, a number of processes was explored for the SER reduction of aircraft starting from electric discharges in flows of air around atmospheric pressure. Absorption calculs of a wave EM by a homogeneous plasma shows the importance of electrons number Ne necessary for a significant attenuation in the ionized ambient air. However, the maintenance of free electrons proves to be difficult in a mixture N2 - O2 (vibrationel excitation of molecule N2 by electrons and electronic attachment on the molecule O2). Only detachment of negative ions O2- by excited oxygen O2(a1Dg) produced in the discharge could be likely to maintain a density electronic of about 1012 cm-3. Lastly, stability problems of the electric discharges still limit the use of air plasmas for the furtivity a high pressure. However, two types of discharges likely to overcome these disadvantages were put in evidence: glow discharge negative point - plan (NPP) and discharge a dynamic regulation (DDR)
Chouha, Michel. "Contribution au calcul de puissance résiduelle : estimation des énergies moyennes béta et gamma des produits de fission". Paris 11, 1986. http://www.theses.fr/1986PA112311.
Pełny tekst źródłaLossouarn, David. "Etude théorique et expérimentale du refroidissement diphasique à pompage capillaire de convertisseurs de puissance à haute densité de flux de chaleur pour la traction ferroviaire". Poitiers, 2007. http://theses.edel.univ-poitiers.fr/theses/2008/Lossouarn-David/2008-Lossouarn-David-These.pdf.
Pełny tekst źródłaOnboard power electronics provides essential functions to the electric traction. The strong miniaturization of semiconductors implies ever growing heat flux densities. In addition, the reliability of existing cooling systems is still imperfect and justifies the use of a capillary device pumping. This thesis is therefore dedicated to characterization of an innovative capillary pumped cooling loop, tailored to high flux densities and offering greater reliability. Emphasis is placed on the transfer of heat and mass for a fluid phase immersed in porous media and subjected to high heat densities. This experimental study leads to an analysis of data collected through a nodal model coupled to inverse techniques. This is made in order to retrieve the parameters used to associate overheating to corresponding heat flux density and finally analyze the variations depending on the characteristics of the porous medium. The method made it possible to trace concentrations in the range of 100 W. Cm-2 applied to the porous medium. Secondly, a detailed presentation of the loop phase, using this kind of flow, is focused on the originality of the architecture used in relation to the usual two phase loops. Tests are performed by scanning a variety of parameters such as heat density injected to the evaporator or pressure drop generated by the loop. The early developments brought to a behavioral model helps to analyze some transitory and stationary phases, able to transfer up to 5. 5 kW per evaporator
Goral, Benoit. "Technique et Méthodologie de Conception du Réseau de Distribution d'Alimentation d'une Carte Electronique Rapide à Haute Densité d'Interconnexion". Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLN037/document.
Pełny tekst źródłaToday's economical context leads electronics and high-tech corporations not only to innovate with a sustained rhythm but also to reduce the design cycle of new products. In order to remain competitive, these corporations must release regularly new products with new functionalities or enhancing performances of the last generation of this product. The enhancement from one generation of the product to the other can be quantified by the speed of execution of a task, the package size or form factor, the battery life and power consumption.The design methodology following these constraints is thus very tough. Indeed, integration of new functionalities as miniaturization of products imply a densification of the printed circuit board. The number of layer in the stack up is increased, isolation between nets is reduced, the use of integrated circuits embedding different functions as SOC or SIP implies a multiplication of the number of voltages. Moreover the increase of circuit performances implies a increasing data rate exchanged between component of the same printed circuit board and occasioning a widening of the reference clock and signal frequency spectrum. These design constraints are the root cause of the apparition of electromagnetic compatibility, signal integrity and power integrity issues. Failure risks must then be limited by fully understanding phenomenon occurring on the board by, on one side, realizing a precise dimensioning pre layout analysis aiming the elimination or reduction of the issues at the beginning of the design cycle, and on the other side, validating the layout by post layout simulation once the printed circuit board routed.This study proposed by Thales Communication and Security in collaboration with public research laboratory SATIE (System and Application of Energy and Information Technologies) of Ecole Normale Supérieure de Cachan within a industrial convention for development through research aims to develop a design methodology for power delivery network of digital printed circuit board with the goal of ensuring good behavior without or by reducing the number of prototypes.The first chapter of this manuscript include an introduction to the context of the study, a precise description of the studied system and the physical phenomenon ruling its behavior, and finally a state of the art of the power integrity technique analysis. A presentation of the test vehicle, designed during the work and support of all measurement results will constitute the focus of second chapter. This chapter presents and describes all the scenarios and implementations created for the observation and measurement of Power Integrity phenomenon and realise measurement-simulation results correlation. In a third part, modeling techniques of each element of the Power Delivery Network are described. The validity of the models is proven by correlating simulation results of each element with measurement results. The fourth chapter presents the analysis and design methodology developed from the results of the different modeling techniques presented in the previous chapter. Simulation tools and their configuration are precisely described and simulation results are compared with measurement results obtained on the test vehicle for the whole system. In the fifth chapter, the interest of power delivery network model will be extended to signal integrity analysis demonstrating how including this model allows to obtain simulation results closer from measurement results by running Signal Integrity Power aware simulation. Finally, the last part of this document synthetizes the work realized and presented in this document, takes a critical look on it and proposes future works and orientations to extend knowledges and understanding of Power Integrity Phenomenon
Saint, Pierre Aude. "Méthodes d'analyse génétique de traits quantitatifs corrélés : application à l'étude de la densité minérale osseuse". Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00633981.
Pełny tekst źródłaCarbonneau, Evelyne. "Détermination de l'âge à partir duquel l'amélioration de l'habileté à rétablir l'équilibre devient nécessaire afin de prévenir les chutes chez les personnes vieillissantes". Mémoire, Université de Sherbrooke, 2012. http://hdl.handle.net/11143/6161.
Pełny tekst źródłaPerrier, Christophe. "Etude des huiles et des mélanges à base d'huile minérale pour transformateurs de puissance – Recherche d'une mélange optimal". Phd thesis, Ecole Centrale de Lyon, 2005. http://tel.archives-ouvertes.fr/tel-00141418.
Pełny tekst źródłaIbrahim, Mahmoud. "Conception et optimisation d'Alimentations Sans Interruption". Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAT053/document.
Pełny tekst źródłaThe design of Uninterruptible Power Supplies (UPS) has been successively improved in recent years to achieve efficiency levels of around 95% while minimizing their footprint. The massive use of power electronics for these systems is led to focus all design efforts to increase both efficiency and power density. The constant developments in power electronics provide the designer many options, among them the multi-level and/or interleaved power topologies in order to reduce passive components size, the new technologies of semiconductor materials with the introduction of grand gap components and advanced technology on passive components materials. The choice between these options is a compromise to achieve the predefined objectives, particularly when other constraints appear to limit the space of possible solutions, including thermal aspect, technological limitations or EMI constraints. This work proposes the implementation of multi-objective optimization methodology for the design of power converters with all its constraints. This offers a quick tool to compare the different possibilities of design and to quantify the improvement provided to the converter. To do this, different topological and technological choices were studied with the development of multi-physics models. These models can take discrete variables as input. So, optimized converters could meet industrial requirements covered by real components and their datasheets. To do this, we first establish the different constraints imposed on the UPS within its environment. Identifying solutions to design is carried through a state of the art research in the field of power electronics. Generic models of power structures and discrete multi-physical models of the components are then developed based on analytical approaches by ensuring a good compromise between accuracy and speed of calculation. Finally, multi-objective and multi constraints optimization methodology is performed on the set of design choices to quantify the performances achieved by each of them. Experimental work has been essential for us to validate the models and optimal solutions. Based on the optimization results PFC converter of 4.2kW/L was built is its performance has been validated
Reytier, Thomas. "Modelling fatigue spectra of aircraft structure under gust loads". Toulouse 3, 2012. http://thesesups.ups-tlse.fr/1614/.
Pełny tekst źródłaThis thesis is dedicated to the fatigue and damage tolerance analysis of the aircraft structures under gust loads. The fatigue and damage tolerance analysis is a significant issue in the aircraft structure design. It aims at defining the inspection program of the aircraft structure in order to ensure its safety through its entire life. The first part reviews the state-of-the-art in the various involved topics for the global process for fatigue analysis of aircraft structure under gust loads: the atmospheric turbulence modelling, the load and stress computation by a finite element analysis, the generation of the fatigue spectrum and at the end, the fatigue and damage tolerance analysis. The second part presents the whole process currently implemented at Airbus. The main strengths and weaknesses are pointed out and this en-ables the identification of several improvement axes. From the continuous turbulence model based on the Von Karman Power Spectral Density(PSD), the computed stresses are included according to statistics established from in-flight measurements in the fatigue spectrum in order to build a stress cycle sequence. The input data for the fatigue and damage tolerance analysis are obtained from the definition of the various fatigue mission profiles, the unitary stress values, the dynamic response of the structure and the turbulence statistics. In the third part,a new methodology is presented in order to obtaine efficiently and accurately the temporal stress sequences due to the atmospheric turbulence. This method relies on new results enabling the generation of correlated time signals from the PSD functions. First, the PSD of the various stress components are directly obtained from the Von Karman PSD via a finite element analysis. Then, the correlated temporal stress sequences are generated and distributed in the fatigue spectrum according to the turbulence intensity statistical law. This new process enables the improvement of the stress computation and the fatigue spectrum generation. It replaces the turbulence statistics by stress exceedance statistics which are defined by an analytical formula in a reasonably conservative way. In addition, the lead time to build the input data for the fatigue and damage tolerance analysis is significantly reduced. Results from the fatigue and damage tolerance analysis are presented in order to highlight the quality of the improved processes both in terms of accuracy and lead time
Sahel, Faten. "Contribution à la modélisation du couplage entre les alimentations et les signaux sensibles dans les cartes électroniques à haute densité d'interconnexions". Electronic Thesis or Diss., Sorbonne université, 2022. http://www.theses.fr/2022SORUS053.
Pełny tekst źródłaThe high-density interconnection boards that Atos develop for HPC (High Performance Computing) applications contain processors functioning at very high currents and low voltages, along with high-speed serial links. With HDI (High Density Interconnection) technology, fast switching power supplies create coupling noise on nearby sensitive signals, that can lead to errors in the transmitted data, and in the worst case, may result in a malfunctioning circuit. Therefore, virtual prototyping is required to verify the signals’ behaviour in transmission lines, detect the parasitic effects on sensitive signals due to crosstalk, and thus allowing necessary adjustments to be made to reduce the noise. Today’s EDA tools lack a dedicated application able to model the impact of power supplies on their neighbouring signals. In this thesis, we suggest a simulation method using existing EDA tools, that would allow the modelling of the coupling between power supplies and nearby conductors in HDI boards. The simulation method is first applied to a case study board, then to a more complex one. This virtual prototyping method simplifies the coupling mode detection and allows us to test solutions to reduce the coupling noise, prior to their implementation
Hammou, Abdelkader Djilali. "Contribution à l'étude et à la modélisation du comportement dynamique des emballages". Thesis, Reims, 2012. http://www.theses.fr/2012REIMS026/document.
Pełny tekst źródłaThis thesis presents experimental and numerical studies of drop tests random vibrations of corrugated cardboard packaging containing different foam cushions. An efficient homogenization model for the corrugated cardboard has been developed. In this homogenized model, the corrugated cardboard is represented by a 2D plate. Instead of using a local constitutive law (relating the strains to the stresses) at each material point, the homogenization leads to global rigidities (relating the generalized strains to the resultant forces) for the equivalent homogeneous plate. This model was implemented into the FE software Abaqus. The foam behaviour was experimentally determined and modelled using a crushable foam model of Abaqus. The packages are tested in free fall from a given height on a rigid floor and submitted to white noise random vibrations. The numerical results obtained using the FE simulation with the homogenized model agree well with the experimental results. We have also shown that the contribution of the corrugated cardboard box to the shock and random vibration responses could not be neglected in the design of cushioning package
Ayme, Fabien. "Développement d'une méthode énergétique pour l'évaluation expérimentale des flux acoustiques entrants dans les cavités d'avion". Phd thesis, Ecole Centrale de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-00995861.
Pełny tekst źródłaTaurou, Eléonore. "Utilisation des transistors GaN dans les chargeurs de véhicule électrique". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLC076/document.
Pełny tekst źródłaImprovement of power density is a bigchallenge for embedded electric vehicle chargers.Goal of the study is to reduce the volume of the DCDCcharger which contains a bulky transformer. Thekey point is to use wide band gap transistors (GaN) toincrease the charger switching frequency. High switchingfrequency can improve power density but theinconvenient is the increase of switching and transformerlosses. The PhD dissertation is organized inthree steps. First step is the definition of a charger topology.This topology is optimized to reduce transformerlosses. Second part of the study is the theoreticaldesign of a high power density transformer. A completetransformer parametric model is presented withFinite Element Analysis. Third part present the prototypeand test results of the charger DC-DC. Electricalbehavior, volume and efficiency results are discussedin this part.Universit ´
Feltekh, Kais. "Analyse spectrale des signaux chaotiques". Phd thesis, INSA de Toulouse, 2014. http://tel.archives-ouvertes.fr/tel-01071919.
Pełny tekst źródłaBaudon, Sylvain. "Etude de l'influence des contraintes appliquées sur l'évolution des propriétés diélectriques des couches minces isolantes dans les composants semi-conducteurs de puissance". Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2013. http://tel.archives-ouvertes.fr/tel-01001950.
Pełny tekst źródłaToni, Kotchikpa Arnaud. "Conception et intégration d'un convertisseur buck en technologie 28 nm CMOS orientée plateformes mobiles". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEI049.
Pełny tekst źródłaThis thesis work consists into the design of a 3 states buck converter targeting the improvement of dynamic regulation of microprocessors supplies. The topology of the converter is, at first, implemented in IBMCMOS 180 nm technology to validate the transient performances of the3 states regulator. The prototype in 180 nm, uses an input voltage of 3.6V and outputs a voltage in the range of 0.8V to 2V. Its response to load transients shows about 1% of undershoot and 2 % of overshoot, proving a good dynamic behavior for a simple structure compared to state of the art.The 3 states converter is then integrated in 28 nm CMOS HPM (technologymostly used for microprocessors desgn). The experimental results on the prototype confirm the performances in terms of energy and area savings, aswell as dynamic response. The chip delivers 0.5V to 1.2V from a 1.8V supply,and shows a 90% peak efficiency. The measurements of dynamic regulation show less than 5% of noise on the processor supply and 10 mV/ns outputvoltage switching for DVFS purpose
Touzani, Youssef. "Commande aléatoire du convertisseur Buck-Boost triphasé à prélèvement sinusoïdal du courant". Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2006. http://tel.archives-ouvertes.fr/tel-00693968.
Pełny tekst źródłaGuillotin, Alban. "Étude de la rugosité de surface induite par la déformation plastique de tôles minces en alliage d'aluminium AA6016". Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2010. http://tel.archives-ouvertes.fr/tel-00716025.
Pełny tekst źródłaYammine, Samer. "Contribution to the Synchronous Reluctance Machine Performance Improvement by Design Optimization and Current Harmonics Injection". Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/14555/1/yammine.pdf.
Pełny tekst źródłaMetchueng, Kamdem Syntia. "Stockage de chaleur dans l'habitat par sorption zéolite/H2O". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI059/document.
Pełny tekst źródłaHeat storage systems for residential house heating could contribute to smoothing the load curve and would help prevent the use of the most polluting power plants or electricity imports during consumption peaks. Thermochemical heat storage systems are suitable for the intended application since they have high energy densities and low thermal losses. This thesis focuses on the design of an adsorption heat storage system that would be used to shed the load curve of the heating device of a house or residential district during the winter peak consumption periods. The zeolite/H2O pair, which has interesting features such as a high energy density and meets the conditions of safety required for a heat storage system for housing, is implemented in a modular fixed bed reactor. A 1D pseudo-homogeneous model was developed in order to simulate the performance of a fixed bed of zeolite during the adsorption and desorption of water. The latter was designed so as to facilitate the integration of data on new generations of materials and model couplings. The need to obtain data on the sorption properties of the zeolite/H2O pair to have reliable simulation results has been demonstrated, particularly at low partial pressures of water vapor and under the operating conditions selected. The experimental validation phase shows that the pseudo-homogeneous model provides a satisfactory estimate of criteria such as the autonomy, the responsiveness and the average power delivered during the discharging phase and the charging time. The model is thus a good sizing and management tool of the reactor. A sensitivity analysis, with the method of Morris, showed that improved model estimates require a more accurate assessment of the additional heat of sorption and porosity of the bed. After assessing the heating needs of the LEB house with a thermal model of the latter in cold climate conditions, two heat storage reactors were sized in order to shed the heating system's load curve either between 6 and 8pm or during the coldest week of the year. While the first strategy results in a more compact storage system, the second makes it possible to reduce the number of on/off cycles. The need for predictive control for monitoring the storage system was highlighted. As for the residential district of 50 LEB houses, diversity is considered when estimating the heating needs of the latter during the coldest week in Nancy. The heat source during the charging phase of the container would be industrial waste heat. During the coldest week, two sizings are suggested. For similar load shedding strategies, the comparison of the equivalent storage volume per house in the district with the storage volume for a single house serves highlights the importance of taking into account diversity. In order to meet the heating needs in Nancy, an equivalent volume of 544 liters per house in the district is sufficient whereas 580 liters are needed for a LEB house
Tricomi, Leonardo. "Development of CFD models applied to fluidized beds for waste gasification". Thèse, Université de Sherbrooke, 2017. http://hdl.handle.net/11143/11333.
Pełny tekst źródłaRésumé : Le but de ce projet est de développer un modèle CFD fiable pour étudier la dynamique des fluides d'un lit fluidisé en régime bullant pendant la gazéification de combustibles solides de récupération (CSR) triés à partir de déchets solides municipaux (DSM). La gazéification est un processus thermochimique qui convertit les matériaux contenant du carbone en gaz de synthèse. La mise à l'échelle est difficile dans ce cas car elle implique une chimie complexe combinée aux phénomènes de transfert de chaleur et de masse dans un environnement fluide multiphasique. La modélisation CFD représente un outil potentiel pour prédire l'impact de la configuration du réacteur et des conditions de fonctionnement sur le rendement, la composition et les contaminants potentiels du gaz. La validation des simulations CFD pour de tels systèmes a été jusqu'à présent possible grâce à l’utilisation de différents outils expérimentaux sophistiqués, permettant de lier le modèle aux données expérimentales. Toutefois, un tel équipement de pointe n’est pas toujours disponible, en particulier à l'échelle industrielle. Par conséquent, ce travail se concentre sur l'étude de la précision et de la sensibilité numérique de deux modèles CFD différents, utilisés dans la caractérisation des flux de particules solides denses dans les lits fluidisés bouillonnants. Le paramètre clé adopté pour décrire et quantifier le comportement dynamique de ce système multiphase est la distribution de la densité spectrale de puissance (DSP) des fluctuations de pression. La fonction DSP a été utilisée pour évaluer la précision des modèles CFD en utilisant un ensemble de conditions de fonctionnement. Le même type d'analyse, étendu à une plus large gamme de conditions de fonctionnement, peut conduire à une validation robuste des modèles numériques présentés dans ce travail. En dépit de sa simplicité de mesure, les données de chute de pression présentent une importante corrélation avec les lits fluidisés, de plus, leur interprétation pourrait aider à améliorer ces technologies très rapidement, poussant les modèles CFD plus près des applications.
Bulusu, Sri Satish Krishna Chaitanya. "Performance Analysis and PAPR Reduction Techniques for Filter-Bank based Multi-Carrier Systems with Non-Linear Power Amplifiers". Thesis, Paris, CNAM, 2016. http://www.theses.fr/2016CNAM1042/document.
Pełny tekst źródłaThis thesis is part of the European FP7 EMPHATIC project (Enhanced Multicarrier Techniques for Professional Ad-Hoc and Cell-Based Communications) including various European universities and two main industrial partners: THALES Communications Security and CASSIDIAN. The EMPHATIC objective is to develop, evaluate and demonstrate the capability of enhanced multi-carrier techniques to make better use of the existing radio frequency bands in providing broadband data services in coexistence with narrowband legacy services. The project addresses the Professional Mobile Radio (PMR) application. The main idea is to analyze the viability of broadband systems based on filter-bank multi-carrier (FBMC) clubbed with o ffset quadrature amplitude modulation (OQAM) in the context of the future 5th Generation (5G) radio access technology (RAT). Increasingly, the FBMC-OQAM systems are gaining appeal in the probe for advanced multi-carrier modulation (MCM) waveforms for future communication systems. This advanced modulation scheme o ers numerous advantages such as excellent frequency localization in its power spectral density (PSD), a robustness to phase noise, frequency off sets and also to the multi-user asynchronism; making it more appealing than OFDM for PMR, cognitive radio (CR) and 5G RAT. However, like any other MCM technique, FBMC-OQAM suff ers from high PAPR. When the power amplifi er (PA) non-linearity, which is realistic radio-frequency impairment, is taken into account; the good frequency localization property is severely compromised, due to the spectral regrowth. The first objective of this PhD thesis is, to predict the extent of the spectral regrowth in FBMC-OQAM systems, due to the PA non-linearity. The second objective is to probe techniques for FBMC-OQAM systems, such as PAPR reduction and PA linearization, in order to mitigate the NL eff ects of PA. By cumulant analysis, spectral regrowth prediction has been done for FBMC-OQAM systems. Also, some algorithms for PAPR reduction, which are based on probabilistic approach and adding signal methods, have been proposed. The coexistence capability of the FBMC-OQAM based broadband system with the narrowband PMR systems in the presence of PA has been analyzed and it has been found that coexistence is possible, provided there is a symbiotic combination of PA Input Back-off (IBO), PAPR reduction and PA linearization. Finally, a novel PA linearization technique has been proposed for FBMC-OQAM
Autret, Solenn. "Retournement temporel des ondes acoustiques en milieux aléatoires". Toulouse 3, 2006. http://www.theses.fr/2006TOU30252.
Pełny tekst źródłaThis thesis is dedicated to the study of the distribution of the acoustic waves in one dimensional random media. The studied acoustic waves are those incoming from a time reversal experiment (TR) organized by Mathias Fink and his team in the Laboratory " Waves and Acoustics. " We bring to light why the profile of the waves obtained after TR does not depend on realizations of the random media unlike the waves not returned temporarily which have for profile a Gaussian process such as its power spectral density is solution of a system of equations of determinist transport, the coefficients of which depend on macroscopic variations of the media. Furthermore, the profile of the wave ater TR can spell as the married of the incidental signal with the power spectral density. The robustness of TR is then tested when errors of recording are made and when the random media changes between both phases of TR
Bulusu, Sri Satish Krishna Chaitanya. "Performance Analysis and PAPR Reduction Techniques for Filter-Bank based Multi-Carrier Systems with Non-Linear Power Amplifiers". Electronic Thesis or Diss., Paris, CNAM, 2016. http://www.theses.fr/2016CNAM1042.
Pełny tekst źródłaThis thesis is part of the European FP7 EMPHATIC project (Enhanced Multicarrier Techniques for Professional Ad-Hoc and Cell-Based Communications) including various European universities and two main industrial partners: THALES Communications Security and CASSIDIAN. The EMPHATIC objective is to develop, evaluate and demonstrate the capability of enhanced multi-carrier techniques to make better use of the existing radio frequency bands in providing broadband data services in coexistence with narrowband legacy services. The project addresses the Professional Mobile Radio (PMR) application. The main idea is to analyze the viability of broadband systems based on filter-bank multi-carrier (FBMC) clubbed with o ffset quadrature amplitude modulation (OQAM) in the context of the future 5th Generation (5G) radio access technology (RAT). Increasingly, the FBMC-OQAM systems are gaining appeal in the probe for advanced multi-carrier modulation (MCM) waveforms for future communication systems. This advanced modulation scheme o ers numerous advantages such as excellent frequency localization in its power spectral density (PSD), a robustness to phase noise, frequency off sets and also to the multi-user asynchronism; making it more appealing than OFDM for PMR, cognitive radio (CR) and 5G RAT. However, like any other MCM technique, FBMC-OQAM suff ers from high PAPR. When the power amplifi er (PA) non-linearity, which is realistic radio-frequency impairment, is taken into account; the good frequency localization property is severely compromised, due to the spectral regrowth. The first objective of this PhD thesis is, to predict the extent of the spectral regrowth in FBMC-OQAM systems, due to the PA non-linearity. The second objective is to probe techniques for FBMC-OQAM systems, such as PAPR reduction and PA linearization, in order to mitigate the NL eff ects of PA. By cumulant analysis, spectral regrowth prediction has been done for FBMC-OQAM systems. Also, some algorithms for PAPR reduction, which are based on probabilistic approach and adding signal methods, have been proposed. The coexistence capability of the FBMC-OQAM based broadband system with the narrowband PMR systems in the presence of PA has been analyzed and it has been found that coexistence is possible, provided there is a symbiotic combination of PA Input Back-off (IBO), PAPR reduction and PA linearization. Finally, a novel PA linearization technique has been proposed for FBMC-OQAM
Niu, Shiqin. "Conception, optimisation et caractérisation d’un transistor à effet de champ haute tension en Carbure de Silicium". Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI136/document.
Pełny tekst źródłaSilicon carbide (SiC) has higher critical electric field for breakdown and lower intrinsic carrier concentration than silicon, which are very attractive for high power and high temperature power electric applications. In this thesis, a new 3.3kV/20A SiC-4H JFET is designed and fabricated for motor drive (330kW). This breakdown voltage is beyond the state of art of the commercial unipolar SiC devices. The first characterization shows that the breakdown voltage is lower (2.5kV) than its theoretical value. Also the on-state resistance is more important than expected. By means of finite element simulation the origins of the failure are identified and then verified by optical analysis. Hence, a new layout is designed followed by a new generation of SiC-4H JFET is fabricated. Test results show the 3.3kV JFET is developed successfully. Meanwhile, the electro-thermal mechanism in the SiC JFETs under short circuit is studied by means of TCAD simulation. The commercial 1200V SIT (USCi) and LV-JFET (Infineon) are used as sample. A hotspot inside the structures is observed. And the impact the bulk thickness and the canal doping on the short circuit capability of the devices are shown. The physical models validated by this study will be used on our 3.3kV once it is packaged
Nasser, Abbass. "Spectrum sensing for half and full-duplex interweave cognitive radio systems". Thesis, Brest, 2017. http://www.theses.fr/2017BRES0006/document.
Pełny tekst źródłaDue to the increasing demand of wireless communication services and the limitation in the spectrum resources, Cognitive Radio (CR) has been initially proposed in order to solve the spectrum scarcity. CR divides the communication transceiver into two categories: the Primary (PU) or the Secondary (SU) Users. PU has the legal right to use the spectrum bandwidth, while SU is an opportunistic user that can transmit on that bandwidth whenever it is vacant in order to avoid any interference to the signal of PU. Hence the detection of PU becomes a main priority for CR systems. The Spectrum Sensing is the part of the CR system, which monitors the PU activities. Spectrum Sensing plays an essential role in the mechanism of the CR functioning. It provides CR with the available channel in order to access them, and on the other hand, it protects occupied channels from the interference of the SU transmission. In fact, Spectrum Sensing has gained a lot of attention in the last decade, and numerous algorithms are proposed to perform it. Concerning the reliability of the performance, several challenges have been addressed, such as the low Signal to Noise Ratio (SNR), the Noise Uncertainty (NU), the Spectrum Sensing duration, etc. This dissertation addresses the Spectrum Sensing challenges and some solutions are proposed. New detectors based on Cyclo-Stationary Features detection and the Power Spectral Density (PSD) of the PU are presented. CanonicalCorrelation Significance Test (CCST) algorithm is proposed to perform cyclo-stationary detection. CCST can detect the presence of the common cyclic features among the delayed versions of the received signal. This test can reveal the presence of a cyclo-stationary signal in the received mixture signal. Another detection method based on the cumulative PSD is proposed. By assuming the whiteness of the noise (its PSD is at), the cumulative PSD approaches a straight line. This shape becomes non-linear when a telecommunication signal is present in the received mixture. Distinguishing the Cumulative PSD shape may lead to diagnose the channel status.Full-Duplex Cognitive Radio (FD-CR) has been also studied in this manuscript, where several challenges are analyzed by proposing a new contribution. FD functioning permits CR to avoid the silence period during the Spectrum Sensing. In classical CR system, SU stops transmitting during the Spectrum Sensing in order to do not affect the detection reliability. In FD-CR, SU can eliminate the reflection of its transmitted signal and at the same time achieving the Spectrum Sensing. Due to some limitations, the residual of the Self Interference cannot be completely cancelled, then the Spectrum Sensing credibility is highly affected. In order to reduce the residual power, a new SU receiver architecture is worked out to mitigate the hardware imperfections (such as the Phase Noise and the Non-Linear Distortion of the receiver Low-Noise Amplifier). The new architecture shows its robustness by ensuring a reliable detection and enhancing the throughput of SU
Kleilat-Iaaly, Iman. "Contribution à la modélisation mécanique et thermique d'une machine synchroréluctante pour une application véhicule". Thesis, Compiègne, 2021. http://www.theses.fr/2021COMP2641.
Pełny tekst źródłaIn the context of electric and hybrid vehicle applications, the development of low-cost electric machines makes sense. The flux barrier synchronous reluctance motor is proving to be a viable alternative for traction applications, especially automotive, replacing permanent magnet machines. Mechanical and thermal constraints play an essential role in the design of synchronous reluctance motors. The mechanical behavior affects the power density of the machine by limiting its rotational speed. The thermal behavior affects the performance of the machine in terms of torque density by limiting the allowable current density. The work proposed in this thesis consists in developing a multi-physical model of the synchronous reluctance motor with a particular focus on mechanical and thermal aspects. An important part of the work includes an experimental validation of the proposed models. This validation uses a prototype of the synchronous reluctance motor and test facilities available in the laboratory
Poulin, Jennifer M. Sc. "Sur l'étude de la transformation des tests portemanteaux pur séries chronologiques multivariées". Thesis, 2006. http://hdl.handle.net/1866/18182.
Pełny tekst źródłaDesgagné, Alain. "Quelques utilisations de la densité GEP en analyse bayésienne sur les familles de position-échelle". Thèse, 2005. http://hdl.handle.net/1866/17784.
Pełny tekst źródłaRouger, Nicolas. "Intégration monolithique des fonctions d'interface au sein de composants de puissance à structure verticale". Phd thesis, 2008. http://tel.archives-ouvertes.fr/tel-00344847.
Pełny tekst źródład'applications de ces travaux couvrent un large spectre, favorisant l'émergence de convertisseurs de puissance innovants, à haute densité de puissance et coût de fabrication réduit.
Durocher-Jean, Antoine. "Diagnostics spectroscopiques de plasmas d'argon à la pression atmosphérique en présence d'espèces réactives". Thesis, 2019. http://hdl.handle.net/1866/24644.
Pełny tekst źródłaThe research done in this Ph.D. thesis consistently characterizes the physics of argon plasmas at atmospheric pressure in the presence of reactive species. This work is motivated by the obvious deficiencies in the understanding of cold plasmas at atmospheric pressure, which are largely due to the limited number of diagnostic techniques used to characterize them. In this context, optical diagnostics allowing the obtaining of fundamental properties (gas and electron temperature, number density of excited species) are first developed and validated in a microwave argon plasma as well as in a dielectric barrier discharge in argon at atmospheric pressure. In particular, a method coupling optical emission measurements of argon 2p-1s transitions to collisional-radiative modelling of the emitting 2p levels is presented in order to get the electron temperature, as well as a means to obtain the gas temperature by the spectral broadening of emission lines and the number density of argon metastable states from tunable laser diode absorption spectroscopy measurements. Subsequently, these optical diagnostics are used to study the influence adding diatomic gases in microwave argon plasmas, highlighting the efficiency with which they start dominating the discharge kinetics by absorbing most of the supplied power. A comparison between the electron power balance calculated from such optical diagnostics to that obtained from electrical diagnostics is also made in the case of an argon-based dielectric barrier discharge with anhydride precursors. Finally, the fundamental properties of two plasmas jet configurations (one radiofrequency, the other microwave) expanding in ambient air are also examined. In the first case, the effects of ambient air on these properties are featured, while in the second case, the injection position of the organosilicon precursor HMDSO in the plasma jet is studied for the deposition of functionnal coatings on glass substrates. The latter reveals the obtaining of an antifog coating under specific operating conditions, a very promising result for the glass industry.