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Kagnaya, Tchadja. "Contribution à l’identification des mécanismes d’usure en usinage d’un WC-6%Co par une approche tribologique et thermique". Paris, ENMP, 2009. http://pastel.archives-ouvertes.fr/pastel-00005750.
Pełny tekst źródłaThe aim of this work is to study wear mechanisms of WC-6%Co cutting-tools in machining by turning. Damage modes are controlled by complex damage mechanisms. They combine abrasion, adhesion and diffusion. Furthermore, they are highly dependant of the temperature levels at tool/material interfaces. In the present study two mains approaches are considered: on the one hand machining by turning and on the other hand tribological tests. In both cases temperature measurements and temperature modelling have been performed. Complementary results have been obtained, resulting in a better understanding of wear behaviour between WC-6%Co and a C45 steel grade. Mains wear mechanisms were identified. They deal with: - large modifications of the WC-6%Co microstructure due to critical mechanical loadings and to high temperature levels (up to 1200°C), - mobility of WC grains due to the viscoplastic behaviour of the cobalt based binder phase at high temperature. Such a mobility leads to intergranular microcracking phenomena and to WC fragmentation and debonding mechanisms, - intragranular microcracking and strain phenomena, that can lead to WC grain fragmentation, due to stress concentrations, - abrasion due to extracted WC fragments and to hard particules extracted from the C45 steel too, - adhesion, particularly at the end of the contact area between tool and chip
Motta, Mariane Prado. "Contribution à l’étude de systèmes de surveillance de l'usinage basés sur des méthodes d‘apprentissage machine et des mesures de vibrations, efforts et température de coupe". Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0296.
Pełny tekst źródłaMachining is an economically important manufacturing process that relies on the use of a sharpened cutting tool to mechanically cut and remove material from a part to achieve a desired geometry. Given the ever-increasing demands for quality, product variability and cost reduction, tool condition and workpiece quality monitoring systems based on artificial intelligence (AI) techniques are a potential solution are a potential solution for a more reliable and economical manufacturing processes. Recent developments in the field of AI, have shown great potential to transform the manufacturing domain with advanced tools dedicated to data analysis and modeling. In particular, supervised machine learning (ML) algorithms are a powerful tool for modeling complex relationships between input and output variables based on a dataset containing examples, i.e., input-output pairs. Nevertheless, one of the main drawbacks of these modeling techniques is that a large amount of data, usually obtained through experiments (often long and expensive to perform), is required to train accurate and reliable models. This fact limits the applicability of these types of models in an industrial context. Considering this context, this study aims to contribute to the identification of methodologies for the development of ML models dedicated to machining monitoring within industrial conditions, in which time and resources for the realization of experiments are often limited. For this purpose, it is considered in this study that, although experiments can be onerous, in the industry it is common that, before starting large scale machining productions with a new tool or material, setup experiments are performed to determine the most appropriate cutting parameters to perform that production. Given this need (or recommendation), it will be investigated in this thesis, the predictive performances that can be achieved if data, obtained from these tuning experiments, are used to generate predictive models for machining monitoring. More precisely, setting experiments from the standardized methodology Couple Tool-Material protocol (NF E 66-520) are considered. In an effort to obtain good predictive performance with a limited amount of experimental data, sensors for measuring cutting forces, temperature and vibrations are chosen as instrumentation for the monitoring system to be developed, given its close relationship with the kinematics of the machining process. In this matter, special attention is given to the feature engineering step. That is, the process of transforming the available raw data, for example, the signals recorded by the sensors, into features, i.e., information, that more accurately represent the problem underlying the predictive model. Finally, since in the industry the changes in cutting tool reference can occur quite often, it will also be investigated whether the models developed for a given target tool can be applied to other slightly different tools (variations on nose radius, substrate and coating) and whether, for the training of ML models, the use of larger databases, but containing observations related not only to the target tool but also to other tools slightly different from it, will be more advantageous, compared to the use of a smaller database specific to the target tool
Ramirez, Christophe. "Critères d’optimisation des alliages de TITane pouraméliorer leur USinabilité". Thesis, Paris, ENSAM, 2017. http://www.theses.fr/2017ENAM0006/document.
Pełny tekst źródłaThe massive introduction of titanium alloys onto the aeronautical structures parts has raised new problems in the machining process. Because of their low thermal properties (refractory materials), they are considered as difficult to cut material. The industrial aim is therefore to improve the productivity of the titanium alloy’s machining and to reduce their costs. Some research on Ti6Al4V α + β, Ti54M and β-treated Ti6Al4V cutting was carried out to point out machinability’s differences between these three materials. This work highlights a strong influence of the orthotropic behavior and the heterogeneity of the lamellar microstructure as well as the grain size of the β-treated Ti6Al4V on cutting. The study on the tool wear diffusion shows that the main diffusion element is titanium and therefore no difference is observed between those three materials. To check that diffusion is the main wear mode, instrumented drilling tests with a wireless temperature measurement device were performed. Temperatures behind the cutting edge reach temperatures above 500 °C for low cutting speeds. At this temperature the phenomenon of diffusion is thermally activated. Finally, in order to have an understanding of the machinability consistencies, a research on the materials’ behavior (Johnson-Cook) and the implementation of a numerical simulation were realized. The simulations carried out, using the previously identified behavior’s laws, model precisely the machining of the Ti6Al4V α+β and Ti54M. The heterogeneity of the β-treated Ti6Al4V does not allow a good modeling of the chip formation. Polycrystalline modeling would be more appropriate
Poser, Christophe. "Influence de la température sur la phénologie de la canne à sucre : conséquences sur la phase d'implantation de la culture dans les Hauts de La Réunion". Thesis, La Réunion, 2013. http://www.theses.fr/2013LARE0030/document.
Pełny tekst źródłaThis thesis is centered on the effects of temperature on sugarcane development and its potential for geographical expansion under low temperatures in high-altitude tropical conditions. In the highlands of Reunion Island (les Hauts), the duration of the germination, in planting years, affects the date and the level of the first harvest, as well as the sugarcane yield in the following ratoon crop cycle. Trials took place in climate chambers, greenhouses and fields at different temperatures and altitudes. A preliminary study validates the conditions governing the experimentation: bud bursts can be studied through single, healthy, single bud cuttings that are taken from the middle section of the mature stem. Temperature considerably influences the primary tiller germination and emergence stages. The thermal model that was developed satisfactorily predicts bursting at a constant temperature and allows for the quantification of observed varietal differences. Field trials reveal a disparity in the production and growth dynamics of leaves and stems according to locations and varieties. Temperature influences this differentiation. Among the indicators that were elaborated, the duration for the seedling of half the population, when applied to a climatic database, allows one to define geographical zones and time periods conducive to the introduction of sugarcane according to its variety. The methods presented herein can be used in varietal selection for all zones where cold temperature limits the spread of crops. Results could be used for the development of new cultural practices or for further studies in geo-referenced agronomic zoning
Guillot, Émilien. "Étude expérimentale des transferts de chaleur à une interface pièce-outil de coupe". Nantes, 2009. http://www.theses.fr/2009NANT2005.
Pełny tekst źródłaThe study relates to the characterization of the interface of contact sliding piece-tool under great deformations representative of the secondary shear zone of a HSM process. The literature shows that the authors consider a perfect thermal contact condition and suppose that the heat flux generated by friction is divided in the ratio of the thermal effusivities of materials in contact. However the distribution of the strain at this interface is huge and the thermal contact must become poor before the release of the chip. The goal of the thesis is to propose an experimental methodology (founded to the measure of the temperature field by thermocouples and its analysis by inverse technique) in order to determine the contact parameters describing a sliding contact seat of a heat dissipation : α , Rtc et φg The measurement principle presents an original approach which treats in a sequential way and by subdomain the zones on both sides of the interface. The thermal conditions which prevail on the contact surfaces are estimated singly. Then, generated heat flux (φg ) and in a simultaneous way α and Rtc et φg are estimated. We have studied the instrumentation by thermocouples in order to control the compromise sensitivity/precision and to well understand the intrusive character of thermocouples set up. Experiments were carried out on friction device that reproduces the mechanics and thermals contact conditions of a HSM process at the tip tool. The experimental plan allows to study the influence the sliding speed and the nature of the tribological couple on the thermal parameters of contact
Voyen, Serge. "Contribution à une modélisation de la répartition des températures dans un matériau fritté : Application à l'étude des outils de coupe". ENSMP, 2000. http://www.theses.fr/2000ENMP1033.
Pełny tekst źródłaKataya, Zeinab. "Effets de température sur les nanoparticules de CoAg : structure et effets de ségrégation". Phd thesis, Université d'Orléans, 2013. http://tel.archives-ouvertes.fr/tel-01004367.
Pełny tekst źródłaLlavé, Campos Angela Magali. "Effets de l'angle d'attaque, de l'orientation de coupe et de la profondeur de coupe sur les efforts de coupe et la qualité de surface du bois d'épinette noire". Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28575/28575.pdf.
Pełny tekst źródłaMerzouki, Abderrahmane. "Les effets d'une coupe à blanc sur l'activité biologique d'un sol fersiallitique méditerranéen". Montpellier 2, 1986. http://www.theses.fr/1986MON20145.
Pełny tekst źródłaMerzouki, Abderrahmane. "Les Effets d'une coupe à blanc sur l'activité biologique d'un sol fersiallitique méditerranéen". Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb375996090.
Pełny tekst źródłaMieusset, Roger. "Effets de la température sur les fonctions testiculaires et épididymaires". Paris 11, 1992. http://www.theses.fr/1992PA11T022.
Pełny tekst źródłaManel, Stéphanie. "Modélisation de la durée de développement pré-imaginal chez les poïkilothermes sous régime de températures variables". Lyon 1, 1995. http://www.theses.fr/1995LYO10277.
Pełny tekst źródłaRoussy, Laurent. "Étude du comportement des matériaux composites aux températures cryogéniques". Besançon, 1994. http://www.theses.fr/1994BESA2050.
Pełny tekst źródłaDaviller, Guillaume. "Etude numérique des effets de température dans les jets simples et coaxiaux". Phd thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2010. http://tel.archives-ouvertes.fr/tel-00573368.
Pełny tekst źródłaJean-St-Laurent, Mathilde. "Effets des cycles extrêmes de température sur le comportement des matériaux composites". Master's thesis, Université Laval, 2014. http://hdl.handle.net/20.500.11794/26398.
Pełny tekst źródłaThis master dissertation presents the effect of extreme temperature cycles on composite materials of carbon fiber and cyanate-ester resin made of five harness woven fabrics. Three laminates and one sandwich plate were studied. The evaluation of damage present in the laminates showed two different types of damage: vertical microcracks and debonding between the fibers and the matrix. Debonding is only visible on the edges of the laminates. As for the microcracks, they are present both on the edges and inside of the laminates, but in greater quantity on the edges. The damage inside the sandwich plate is present under two forms: vertical microcracks and delamination due to the presence of the adhesive. The effect of thermal cycling on the degradation of the mechanical properties of the laminates was also studied. The mechanical tests performed showed that properties influenced by the matrix behavior were altered by the presence of microcracks.
Ishiguro, Naoko. "L'influence du climat et des affluents sur l'oxygénation et la turbidité des lacs : le cas comparé du Léman, des lacs alpins et japonais". Limoges, 2004. http://www.theses.fr/2004LIMO2002.
Pełny tekst źródłaBouhanek, Karima. "Oxydation à haute température de superalliages monocristallins". Toulouse, INPT, 1997. http://www.theses.fr/1997INPT016G.
Pełny tekst źródłaPeigne, Grégoire. "Etude et simulation des effets dynamiques de la coupe sur la stabilité de la coupe et la qualité géométrique de la surface usinée : application au fraisage de profil". Grenoble INPG, 2003. http://www.theses.fr/2003INPG0133.
Pełny tekst źródłaMykytczuk, Nadia, Leo Leduc, Jack T. Trevors i Garry D. Ferroni. "Effets des facteurs environnementaux du drainage minier acide sur les membranes d'Acidithiobacillus ferrooxidans". Acfas-Sudbury, 2007. https://zone.biblio.laurentian.ca/dspace/handle/10219/96.
Pełny tekst źródłaGhasemzadeh, Hasan. "Couplages dans les géomatériaux multiphasiques : effets de la température et de la chimie". Phd thesis, Ecole des Ponts ParisTech, 2006. http://pastel.archives-ouvertes.fr/pastel-00002077.
Pełny tekst źródłaKoo, Min. "Effets de température dans les procédés de gravure plasma : Aspects fondamentaux et applications". Phd thesis, Université Joseph Fourier (Grenoble), 2008. http://tel.archives-ouvertes.fr/tel-00355029.
Pełny tekst źródłaHammouda, Tahar. "Mécanismes et cinétique de fusion partielle d'assemblages à Fluor-Phlogopite : modélisation, expérimentation et implications géochimiques". Orléans, 1995. http://www.theses.fr/1995ORLE2015.
Pełny tekst źródłaReyt, Françoise. "Influence de la température sur la liaison calcium-protéine". Bordeaux 2, 1997. http://www.theses.fr/1997BOR2P017.
Pełny tekst źródłaBaril, Eugénie. "Quantification de l'influence de l'environnement sur la formation et la thermo-résistance des spores bactériennes". Brest, 2011. http://www.theses.fr/2011BRES2047.
Pełny tekst źródłaThe aim of this PhD study was to quantify the influence of the sporulation environment (temperature, pH and aw) on the spore formation of Bacillus weihenstephanensis and B. Licheniformis and on their heat resistance. A two-step sporulation methodology was developed to study sporulation in environmental conditions close to growth boundaries. Sporulation boundaries (temperature, pH and aw) were observed inner growth boundaries. A primary model was proposed to quantify the influence of the environment on spore formation. A decrease in sporulation temperature and pH delayed the time to first spore per ml. The maximal spore heat resistance was observed for spores produced at temperature and pH close to the optimal growth values. A secondary model was then proposed and validated to estimate the spore heat resistance as function of the sporulation and heat treatment environments. Finally, this study allows defining control points in foodstuff to prevent spores in food products. A relationship between the influence of environmental temperature and pH on growth and sporulation was pointed out
Desserrey, Franck. "Comportement mécano-chimique du nickel vis à vis de l'oxygène à haute température : aspects expérimentaux et prévisionnels". Dijon, 2002. http://www.theses.fr/2002DIJOS057.
Pełny tekst źródłaDasriaux, Marion. "Evolutions microstructurales du PEEK au-dessus de sa température de transition vitreuse lors de maintiens sous pression et température". Phd thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2012. https://theses.hal.science/docs/00/78/60/16/PDF/Manuscrit_Dasriaux_Marion.pdf.
Pełny tekst źródłaAt least one fraction of the amorphous phase of semi-crystalline polymers, confined by the crystalline lamellae, is in out-of-equilibrium state, so that "physical aging" or "secondary crystallization" features can be observed (e. G. , by calorimetry) even above the glass transition temperature. This issue has already been addressed in the literature in several semi-crystalline polymers at atmospheric pressure. But despite the well-known influence of pressure on molecular mobility, the pressure-sensitivity of these microstructure rearrangements has never been tackled. This study focuses on amorphous evolution occurring in highly pressurized Poly-Ether-Ether-Ketone (PEEK), in comparison with atmospheric pressure. The phenomenon is tracked by Differential Scanning Calorimetry (DSC). A significant influence of pressure is evidenced, pressure confining rearrangements within spatially limited domains. The stability and co-existence of reorganization processes upon successive annealings is also investigated. Finally, relationships between constrained and free amorphous phase rearrangements are discussed. The free fraction of the amorphous phase results relaxed after annealing at atmospheric pressure and stabilized into a denser state after high pressure annealing. All these results allow to discuss the phenomena involved in the microstructural evolution of PEEK: a "physical aging" or "secondary crystallization"
Le, Morvan Caroline. "Effets des températures extrêmes sur l'expression des défenses immunes chez la carpe (Cyprinus carpio) : corrélation avec la dynamique membranaire des leucocytes périphériques". Lyon 1, 1995. http://www.theses.fr/1995LYO10055.
Pełny tekst źródłaAddala, Farida. "Etude du comportement rhéologique des bitumes à moyenne et basse température". Lyon, INSA, 1989. http://www.theses.fr/1989ISAL0066.
Pełny tekst źródłaThis study, performed in the framework of a collaboration with the Compagnie française de Raffinage Total France, is part of a general study on the rheological behaviour of bitumen. More specifically, our contribution consists of the development of an experimental apparatus allowing mechanical behaviour study of the bituminous material at low and medium temperature. In a first part we present the state of the art in this domain from experimental as well as theoretical point of view. In the the second part we describe the developed apparatus for torsion-compression tests on hollow cylindrical sample and we analyse the experimental results we have obtain. Finally the third part deals with numerical computations by the finite element method of the tests described in the previous part as well as the penetration tests. Different non-linear viscoelastic models have been used for this purpose after calibration of their parameters according to the experimental results
Le, Blanc Mélanie-Louise. "Réaction des micromammifères et des oiseaux à différentes intensités de coupe en forêt boréale irrégulière". Master's thesis, Université Laval, 2009. http://hdl.handle.net/20.500.11794/20907.
Pełny tekst źródłaDardié, Jason. "Étude des effets des rayonnements sur les matériaux et systèmes électroniques". Thesis, Montpellier, 2020. http://www.theses.fr/2020MONTS001.
Pełny tekst źródłaTMI-Orion, a company specialising in systems for acquiring physical parameters (pressure, temperature, humidity, etc.) for harsh environments, wishes to diversify, particularly in the civilian nuclear markets or the new space. These two markets are subject to strong radiative stress. The company, which is at the origin of the thesis, wishes to develop its skills with regard to radiative stress in order to be able to propose applications in these sectors. This thesis was therefore conducted with the main objective of providing as much information as possible on radiative stress to TMI-Orion. We have therefore identified four areas of work to address this issue.In the context of this thesis, we began by describing the radiative environments encountered in the space and civilian nuclear fields. Then the mechanisms of radiation-matter interaction were defined. Finally, the effects of radiation on electronics have been given.The second area of work consists of a study of the degradation mechanisms of elementary electronic components (MOS and bipolar transistors) as a function of the temperature to which they are subjected during irradiation. The effect of low (up to 100 K) and high (up to 400 K) irradiation temperatures on the degradation of elementary components was studied. During this study we were also able to compare the degradation obtained between a cobalt-60 irradiation and an X-ray irradiation.The third area of work consists of a simulation study on shielding against radiative stress. As part of this work, we have developed two calculation codes on GEANT4. The first one allows to study the dose deposited by a cobalt-60 source for different shielding conditions. The second one allows to model the X-ray generator of the IES laboratory and gives its energy spectrum. The effect of different filters on the spectrum is also studied.The last axis of this thesis work consists of a complete reliability study on autonomous data loggers developed by TMI-Orion. One particular recorder, the PicoVACQ, is used as an example. The reliability of this recorder was calculated by an analytical method, studied using the feedback available within the company, measured against thermal stress and measured against radiative stress. Finally, the search for a microcontroller, a central component of a radiation-tolerant data acquisition system, was carried out. One microcontroller in particular appears to have good resistance to dose effect and will probably be used by the company in its future projects
Racinais, Sébastien. "Performance de courte durée en milieu tropical:Influence de la Température environnementale et du moment de la journée". Antilles-Guyane, 2004. http://www.theses.fr/2004AGUY0118.
Pełny tekst źródłaMuscular power display a significant diurnal increase in a neutral environment only and a 60-minute moderately warm exposure increases muscular power in the morning only when body temperatures are their lowest (Sudy 1). The fact that the passive warm-up effect body temperature can not be combined may be explained by their similar action on muscular contractile properties (study 2). These results point to the existence of a "ceiling" above which an increase in body temperature fails to improve muscular performance. Indeed,our results show that an extremely hot exposure fails to modify short term performance in a moderately warm and humid environment (study 3). Similary to tropical climate,a 30-minute leg immersion in a hot bath in neutral environment may blunt the diurnal variation in muscular power (study 4),whereas active warm-up increases muscular power both in the morning and in the evening(sTUDY 5)
Rioux, Jérôme. "Effets de la coupe avec la protection des petites tiges marchandes (CPPTM) et de la coupe avec la protection de la haute régénération et des sols (CPHRS) sur la faune de la pessière noire à mousses de l'Est". Thesis, Université Laval, 2006. http://www.theses.ulaval.ca/2006/24072/24072.pdf.
Pełny tekst źródłaTalby, Riad. "Mesure des fluctuations de température avec des thermocouples fins, par référence à un fil "froid"". Aix-Marseille 2, 1987. http://www.theses.fr/1987AIX22011.
Pełny tekst źródłaMenou, Abdellah. "Etude du comportement thermomécanique des bétons à haute température. : Approche multi échelles de l'endommagement thermique". Pau, 2004. https://tel.archives-ouvertes.fr/tel-00008986.
Pełny tekst źródłaThis research work deals within the framework of the study of durability when subjected ti hight temperature in case of fire. The aim of this study is to identify the elementary mechanisms leading the degradation of concretes at hight temperature. Adopted step consists to uncoupling the thermal damage, of mechanical origin (accompanied with deformations) and which takes place in the macrocospic and tiny scale, of the thermal damage of physical and chemical origin (not accompanied with deformations) and which is due mainly to the physical and chemical alterations in material. This approach is based on the exploitation of two different models ; the "Digital Concrete" microscopic model and the macroscopic damage deviatoric model MODEV, both implemented in the F. E. Software SYMPHONIE. Concurrently, an experimental study was achieved in order to feed and to validatez the "Digital Concrete" model. The evolution of mechanical characteristics of concrete was studied using multi-scale approach and three point bending tests were performed on five cementeous materials. Multi-scales approach of the model "Digital Concrete" allowed to find by simulation the experimental warmly behaviour. This approach allowed to put in evidence the existence of the micromechanical deformation and to propose an original approach allowing identification by simulation the laws concretes behaviour at hight temperatures. This approach was also applied successfully to explain the thermoapplication refractory concrete subjected to very hight temperatures was also realized
Raharison, Lucie Hortense. "Exercice maximal, métabolisme musculaire et évolution des températures cutanée et centrale chez les sujets ayant présenté un "syndrome d'hyperthermie d'effort" (HTE)". Aix-Marseille 2, 2001. http://www.theses.fr/2001AIX22093.
Pełny tekst źródłaLaunay, Jean-Claude. "Les adaptations croisées climatiques chez l’humain : caractérisation, mécanismes et risques thermophysiologiques". Lyon 1, 2008. http://www.theses.fr/2008LYO10062.
Pełny tekst źródłaIntercontinental travels, but also overseas deployment of troops may submit adapted persons to a given thermal strain to an opposite thermal strain, exposing them to unassessed thermophysiological risks. This problem encompassed the poorly researched concept of thermal cross-adaptation. Using sweating tests (Tdb=45 °C, RH=10 %, 90 min) and standard cold air tests (Tdb=1 °C, 120 min) in humans, before and after heat acclimatization (28 d in French Guyana) or cold acclimatization (55 d in Artic), we characterized heat/cold and cold/heat cross-adaptations. The thermophysiological mechanisms involved in their development were described in 24 subjects submitted to different thermal loads. The resulting thermophysiological risks were evaluated. A methodology for studying, characterizing and assessing the medical risks for other cross-adaptations is proposed in order to optimize the medical prevention
Dasriaux, Marion. "Evolutions microstructurales du PEEK au-dessus de sa température de transition vitreuse lors de maintiens sous pression et température". Phd thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2012. http://tel.archives-ouvertes.fr/tel-00786016.
Pełny tekst źródłaMnif, Hassène. "Contribution à la modélisation des transistors bipolaires à hétérojonction Si/SiGe en température". Bordeaux 1, 2004. http://www.theses.fr/2004BOR12786.
Pełny tekst źródłaThe consideration of the temperature and in particular of he self-heating effect in Si/SiGe heterojunction bipolar transistors is a fundamental aspect to predict in a precise way these electric characteristics. The use of these components in microwaves applications exposes to various tempertaures and strong densities of current, accentuates enormously these effects. Consequently, a precie modelling of these phenomena is necessary. A dynamic model describing the self-heatinng, characterized by a rise in the junction temperature, is developed. An electric equivalence close to the analytical model, compatible with SPICE electric models type, is established. A specific test bench is used in order to evaluate the new model and to extracts its parameters. In a second part, the temperature dependence of the various compact model parameters is studied, in particular in the HICUM model
Daniel, Isabelle. "Aluminosilicates à haute pression et haute température : amorphes, verres, liquides et cristaux : étude par spectroscopie Raman". Lyon 1, 1995. http://www.theses.fr/1995LYO10279.
Pełny tekst źródłaCourtial, Yannick. "Etude du comportement mécanique à haute température de cermets WC-Co : Effets de la microstructure". Lyon, INSA, 1991. http://www.theses.fr/1991ISAL0071.
Pełny tekst źródłaCharacterization of mechanical properties of WC-(17,5-25 %) Co cemented carbide at high temperatures (600-1000°C) and particularly of their resistance to crack propagation cannot be done by using the laws of behaviour of fragile materials (elastic range) and on the basis of the only criterion of KIc overload breakage. At this level of temperature, the behaviour of these materials is indeed of elastoplastic type. We have therefore used the notion of R CURVE : curve of resistance to crack propagation. We have thus access to the values of stable growth start of crack, of propagation and to the differentiation of elastic and plastic phenomena. Comparison of the different methods (RICE,GARWOOD and SAKAI) which allow to obtain R curves led us to the following conclusions: the RICE method is the most suitable for WC-Co cermets; KIc RICE corresponds to the start of stable growth of cracks;definition of a criterion as a criterion of overload breakage at hight temperature. We have developed at the same time a DOUBLE TORSION device and have applied this measure to the case of cermets. It has been possible to observe a slow growth of under-critical defects at 600°C. The objective of all these measurements is to observe the influence of MICROSTRUCTURE and COBALT CONTENT on the high temperature mechanical properties of cermets developed by the CERAMETAL (Lux) company
Grenier, Benjamin. "Spectroscopie théorique : description des effets de la température sur les paramètres de résonance magnétique nucléaire". Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0494/document.
Pełny tekst źródła- Our objective is to define a theoretical methodology, which allows to simulate the Nuclear Magnetic Resonance (NMR) spectra taking into account the temperature effects, in order to propose a help to the interpretation of the more relevant experimental results.- To deal with the description of the temperature effects on the NMR parameters, we have studied azacalixarenes, which are cyclic oligomers of phenol units linked together by nitrogen bridges. These molecules have a calyx shape, hence their name azacalixarenes. By this cavity these molecules can capture different types of compounds and are used in the host-guest chemistry field.- A wide variety of substituents can be attached to these azacalixarenes. Experimentally, one can easily follow the structure variations effects, at the level of physicochemical properties by NMR.- For this reason, we first investigated the geometric description of azacalixarenes as a function of different substituents and different isomers using the Density Functional Theory, so without taking into account the temperature. - Then, we simulated the NMR parameters of these systems using the Density Functional Theory. This is to calculate the azacalixarenes NMR spectrum in the ground state.- FInally, by performing molecular dynamics simulations using Molecular Mechanics, we were able to take into account the temperature effects. We were able to simulate the NMR parameters of these systems taking now into account the effects of temperature
Castellano, Aloïs. "Étude des effets de la température sur les combustibles nucléaires par une approche ab initio". Electronic Thesis or Diss., Sorbonne université, 2022. http://www.theses.fr/2022SORUS062.
Pełny tekst źródłaTo ensure the security of nuclear electricity production, an understanding of the behavior of nuclear fuel materials is necessary. This work aims at making a contribution to the study of the effects of temperature on nuclear fuels, by using an ab initio approach through density functional theory and ab initio molecular dynamics (AIMD). To explicity take account of the temperature, a non-perturbative lattice dynamics method is formalised, allowing to study the evolution of phonons and thermodynamic properties with temperature. In order to reduce the important computational cost of AIMD, a machine-learning based sampling method is developped, which allows to accelerate the simulation of materials at finite temperature. Those different methods are applied to describe the stabilisation of uranium-molybdenum alloy at high temperature, as well as the lattice dynamics of uranium and plutonium dioxides
Grenier, Benjamin. "Spectroscopie théorique : description des effets de la température sur les paramètres de résonance magnétique nucléaire". Electronic Thesis or Diss., Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0494.
Pełny tekst źródła- Our objective is to define a theoretical methodology, which allows to simulate the Nuclear Magnetic Resonance (NMR) spectra taking into account the temperature effects, in order to propose a help to the interpretation of the more relevant experimental results.- To deal with the description of the temperature effects on the NMR parameters, we have studied azacalixarenes, which are cyclic oligomers of phenol units linked together by nitrogen bridges. These molecules have a calyx shape, hence their name azacalixarenes. By this cavity these molecules can capture different types of compounds and are used in the host-guest chemistry field.- A wide variety of substituents can be attached to these azacalixarenes. Experimentally, one can easily follow the structure variations effects, at the level of physicochemical properties by NMR.- For this reason, we first investigated the geometric description of azacalixarenes as a function of different substituents and different isomers using the Density Functional Theory, so without taking into account the temperature. - Then, we simulated the NMR parameters of these systems using the Density Functional Theory. This is to calculate the azacalixarenes NMR spectrum in the ground state.- FInally, by performing molecular dynamics simulations using Molecular Mechanics, we were able to take into account the temperature effects. We were able to simulate the NMR parameters of these systems taking now into account the effects of temperature
Rosen, Michel. "Contribution à l'étude des effets du vent et d'un gradient de température sur l'efficacité des écrans acoustiques". Le Mans, 1986. http://www.theses.fr/1986LEMA1007.
Pełny tekst źródłaEl, Babili Mohammed. "Métabolisme branchial de la sphingomyéline et transport du sodium chez deux espèces euryhalines : Dicentrarchus labrax et Carcinus maenas : influence de la température et de la salinté". Lyon 1, 1997. http://www.theses.fr/1997LYO10339.
Pełny tekst źródłaPierrot, André. "Contribution a l'étude des transferts de chaleur à haute température dans les milieux alvéolaires". Perpignan, 1987. http://www.theses.fr/1987PERP0032.
Pełny tekst źródłaTrégon, Bernard. "Evaluation et caractérisation d'une technologie d'assemblage MCM-L pour environnement haute pression forte température (120 MPa, 175°C)". Bordeaux 1, 2002. http://www.theses.fr/2002BOR12580.
Pełny tekst źródłaThe first part of this study is an analysis of electronics needs for severe environmental conditions, that is pressure/temperature combined stress, and so the different potentials applications domains, The second part establish a liste of degradation modes of assembly materials implied in prototypes manufacture. These protoypes are intend to word under 120Mpa of pressure and 175°C of température. Analytic modelisation of each degradation modes are listed; Then we designed and realised an environmental test bench to study our prototypes. The third part is a theoretical behavioural study of components parts under pressure/temperature combined stress. This study has been completed through an experimental analysis. Finally, the fourth part is an experimental analysis of complete prototypes manufactured for our study. This analysis deals about sturdiness of the electronic funcion, so as about the different assembly options degradations of each protoypes. This analysis has been completed with a simulation study using finite elements method
Neuville, Daniel R. "Propriétés thermodynamiques et rhéologiques des silicates fondus". Paris 7, 1992. http://www.theses.fr/1992PA077141.
Pełny tekst źródłaGrignon, Christophe. "Un modèle de thermique 2D appliqué aux structures hétérogènes creuses avec source intérieure mobile en régime fortement varié : le cas du tube d'arme en rafale". Poitiers, 1995. http://www.theses.fr/1995POIT2303.
Pełny tekst źródłaDjezzar, Karina. "Sur l'étirabilité et la biétirabilité de copolymères d'éthylène et d'alcool vinylique". Lille 1, 1995. http://www.theses.fr/1995LIL10087.
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