Thèses sur le sujet « Foresterie – Industrie et commerce – Modèles mathématiques »
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Bauer, Rodolphe. « La modélisation du volume des compartiments riches en composés chimiques extractibles (écorce et nœud) dans six essences d'intérêt des régions Grand-Est et Bourgogne Franche-Comté ». Electronic Thesis or Diss., Paris, AgroParisTech, 2021. http://www.theses.fr/2021AGPT0025.
Texte intégralIn a context of renewal of the chemical industry and the search for new outlets for forestry, extractives are becoming increasingly interesting molecules, both ecologically and financially speaking. In order to evaluate the relevance of these molecules as a new resource for the chemical industry and a potential outlet for forestry, it is necessary to make a preliminary evaluation of the resource. This requires knowledge of the volume of compartments rich in extractable material, particularly bark and knots. The present study therefore focuses on modeling bark and knot volumes. It focuses specifically on two French regions, the Grand Est and the Bourgogne-Franche-Comté, and on six important species, Abies alba, Picea abies, Pseudotsuga menziesii, Quercu robur, Quercus patraea, and Fagus sylvatica.This study is made possible, on one hand, by the use of a large database including numerous measurements of bark thickness made at different heights on the stems of many trees. On the other hand, new samplings have been made to allow X-ray scanning of nodes all along the stem and thus to determine precisely the volume on a computer picture.In order to model the available amount of bark, three types of models were built, models predicting the volume of bark, models predicting the surface area of bark along the stem and models predicting the thickness of bark at 1m30. The former achieved a relative root mean square error (RMSErel) of 16.7% to 27.5% depending on the species.The study of bark area models showed that it was possible to use a model independent of diameter-over-bark but that model using this variable are more accurate. The RMSErel achieved by these bark area models varied between 23 and 38% depending on the species and model considered.This work showed the importance of using the bark thickness at 1m30 as an input data. As it is rarely measured today, it was also modelled using the DBH. This allowed us to show the influence of altitude on bark thickness at 1.30 m for three species: Abies alba, Picea abies, Fagus sylvatica. The models obtained RMSErel of the models ranged from 26.8 to 36 % of RMSErel depending on the species considered.Finally, knot volumes have started to be studied. Although this work has not been fully completed, it already shows the importance of producing new models in order to fit the predicted knot patterns as closely as possible to reality. Moreover, the quantity of these compounds in the wood seems, at this stage of the study, to be too small to provide a large extractable resource, despite their great intrinsic richness. Their interest could therefore be more in the extraction of specific molecules
Ducloux, Pierre. « Modélisation du comportement dynamique et optimisation de la conduite d'une cristallisation discontinue de l'industrie sucrière ». Châtenay-Malabry, Ecole centrale de Paris, 1987. http://www.theses.fr/1987ECAP0061.
Texte intégralFournier, Gilles. « Application des modèles mathématiques de coût à la détermination des investissements dans l'industrie pétrolière ». Dijon, 1997. http://www.theses.fr/1997DIJOE008.
Texte intégralIt is today of paramount importance to realistically forecast the cost and time required to design and manufacture a given product, from the very first phase of the project. Furthermore, with the increasingly rapid development of technology, it is often impossible to draw a direct parallel with existing, well known products. Mathematical models of cost, and map models in particular, have been developed to meet this need. Although one may still refer to former products, they do not automatically have to be "analogous" to the product under consideration, because these methods use "universal relationships" between cost, weight, technology, performance and reliability, and also the nature and experience of the firm manufacturing the product. The purpose of this thesis is to demonstrate the pertinence, and more importantly the potential, of mathematical models of cost for the oil and gas industry, from exploration and production to refining, petrochemicals, and internal combustion engines. After a theoretical examination of estimation methods and a classification of existing ones, emphasis is placed on the logical aspect of these models. In addition, the complementarity between these tools and certain fields such as project management is pointed out, for example with respect to value control. The last chapter of the thesis is devoted to case studies. It aims chiefly at comparing theory with practice in order to identify the limits of mathematical models of cost so that they can be used judiciously
Minegishi, Shotaro. « Performance et fiabilité dans les délais de livraison de produits industriels assemblés : application à l'industrie automobile ». Châtenay-Malabry, Ecole centrale de Paris, 2003. http://www.theses.fr/2003ECAP0904.
Texte intégralArbod, Guillaume. « La croissance économique des pays pétroliers ». Dijon, 2007. http://www.theses.fr/2007DIJOE004.
Texte intégralThe literature tries to apprehend the weakness of the economic growth of oil countries by the assumption of ousted growth factors. In the Dutch Disease models the non-oil exporting sector would be ousted whereas in the analyses in terms of economic policies it would be the effective economic policies. We consider the phenomenon through the growth theories, the oil incomes being regarded as an additional exogenous income for the economy. In this manner the growth dynamic of oil countries, even the most unfavourable, can be modelled without utilizing any concept of economic inefficiency. The last part of our work is devoted to the Saudi economy. After having developed a macroeconometric model, and using scenarios of oil prices, we lead a forecasted analysis of this economy
Poncet, Anthony. « Fiabilité expérimentale : dimensionnement optimal d'essais sous contraintes : modélisation des facteurs endommageant le composant et intégration dans le dimensionnement de l'essai. Application à l'automobile ». Saint-Etienne, 2005. http://www.theses.fr/2005STET4016.
Texte intégralIn industry and in particular in automotive industry, it is important to contain engineering and manufacturing costs of products. However, it is also prejudicial not to contain reliability. Calculation of reliability and more precisely the link between field reliability and reliability in tests require new methods to take in account environmental factors during reliability test in order to validate a component. The developed method allows to have a representation of the damaging factors influences, with a proportional hazard model, in order to size an optimal validation test. The prior knowledge (expert judgments, passed tests,. . . ) is used to estimate these influences
Cadren, Muriel. « Modélisation à court terme des consommations de produits pétroliers en France ». Dijon, 1998. http://www.theses.fr/1998DIJOE007.
Texte intégralThe analysis of petroleum product demand became a privileged thrust of research following the modifications in terms of structure and level of the petroleum markets since eighties. The greatest importance to econometrics models of energy demand, joint works about nonstationary data, explained the development of error-correction models and the cointegration. In this context, the short term econometric modelling of petroleum product demand doesn't only focus on forecasts but also on the measure of the gain acquired from using error- correction techniques and cointegration. It's fitting to take the influence of technical improvement and environment pressures into account in econometric modelling of petroleum products demand. The first part presents the evolution of energy demand in France and more particularly the petroleum product demand since 1986. The objective is to determine the main characteristics of each product, which will help us to analyse and validate the econometrics models. The second part focus on the recent developments in times series modelling. We study the problem of nonstationary data and expose different unit root tests. We examine the main approaches to univariate and multivariate modelling with nonstationary data and distinguish the forecasts of the latter's. The third part is intended to applications. Its objective is to illustrate the theoretic developments of the second part with a comparison between the performances of different approaches (approach box and Jenkins, Johansen approach's and structural approach). The models will be applied to the main French petroleum market. The observed asymmetrical demand behaviour is also considered
Mathurin, Joël. « Applications de la théorie des jeux coopératifs à l'analyse économique de la coopération internationale : illustrations par l'étude du cas de la politique agricole commune ». Toulouse 1, 1997. http://www.theses.fr/1997TOU10081.
Texte intégralBeaudoin, Daniel. « Distributed wood procurement planning within a multi-firm environment ». Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25120/25120.pdf.
Texte intégralDoucet, Carole. « Activités viticoles et développement régional ». Bordeaux 4, 2002. http://www.theses.fr/2002BOR40012.
Texte intégralSboui, Sami. « Modélisation, évaluation des performances et optimisation des flux logistiques d'un réseau d'entreprises partenaires dans la filière Textile-Habillem̀ent-Distribution ». Lille 1, 2003. https://pepite-depot.univ-lille.fr/RESTREINT/Th_Num/2003/50376-2003-117.pdf.
Texte intégralOuedraogo, Boukary. « Éléments économiques pour la gestion de l'offre et de la demande du bois-énergie dans la région de Ouagadougou ». Bordeaux 4, 2002. http://www.theses.fr/2002BOR40035.
Texte intégralDuquenne, Manon. « Incidence de paramètres technologiques sur l'expression de gènes et la production d'entérotoxines de Staphylococcus aureus au cours des 72 h suivant l'empresurage des laits en fabrication fromagère ». Phd thesis, AgroParisTech, 2010. http://pastel.archives-ouvertes.fr/pastel-00569982.
Texte intégralTamini, Lota Dabio. « Le rôle du paiement initial de la Commission canadienne du blé en information imparfaite et analyse des conséquences d'une réduction des tarifs et des subventions - internes et à l'exportation - en présence d'un lien vertical entre les produits ». Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25174/25174.pdf.
Texte intégralBaillet, Séverine. « Optimisation de forme d'une pompe générique de fond de puits ». Phd thesis, Université Henri Poincaré - Nancy I, 2007. http://tel.archives-ouvertes.fr/tel-00344716.
Texte intégralLefevre, Julien. « Hybridization challenges in energy-economy integrated models and representation of the low carbon transition : An application to the Brazilian case ». Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLA003.
Texte intégralThis thesis provides insights about the hybridization challenges in energy-economy integrated models and about the integrated representation of the low carbon transition, and proposes an application to the Brazilian case. Noting the existing gap between the framing of transition issues towards low carbon economies and the results brought by global integrated models, it provides a guide of the available model toolbox which brings a new view on the internal vision of models about energy-carbon-economy transformation pathways. This makes it possible to better delimit the areas of competence of existing tools and to understand some of their limitations. Our work especially underlies the relevance to work under a hybrid approach which articulates a macroeconomic framework with engineering based representations in order to improve the credibility of the assessments produced and we detail the methodological issues to build multi-sector energy-economy hybrid models. Part of the methodological principles are applied to build a tool to analyze the low carbon transition of the medium run in Brazil. We show how a carbon tax policy makes it possible to articulate several policy objectives until 2030 targeting purchasing power, competitiveness, employment and income distribution, beyond climate goals. Our diagnostic underlies the importance of the structural specifics of the energy-economy context in Brazil and of macroeconomic mechanisms linked to trade and labor market rigidities, which are often overlooked in existing studies. We eventually provide specific insights about the articulation between climate and oil policy in Brazil
Senemek, Nuri. « La Politique commerciale endogène : les enseignements de l'expérience européenne (1982-1996) ». Lille 1, 2003. https://ori-nuxeo.univ-lille1.fr/nuxeo/site/esupversions/a00647e2-2482-44ae-a8f4-721c636308b2.
Texte intégralIosif, Ana-Maria. « Modélisation physico-chimique de la filière classique de production d'acier pour l'analyse de l'Inventaire du Cycle de Vie ». Electronic Thesis or Diss., Vandoeuvre-les-Nancy, INPL, 2006. http://www.theses.fr/2006INPL074N.
Texte intégralThis work was devoted to a new methodological framework, which combines the Life Cycle Assessment (LCA) method and the process simulation software (Aspen Plus), in order to improve the quality of data used for carrying out the Life Cycle Inventory (LCI) of the classical steelmaking route. The new approach adopted in the present work, is to carry out the inventory of the defined system via simplified physical-chemical models. Using Aspen Plus software, we have developed simplified physical-chemical models for each of the subsystem defined by the boundaries of the classical steelmaking route: coking plant, sintering plant, blast furnace, basic oxygen furnace and hot rolling. The modelling strategy was based on physical and chemical considerations and on the experimental observations made on an industrial and/or a pilot scale for each subsystem.The models allow for calculation of the principal pollutants evolved by the system such as CO2, CO, NO, SO2, COV, HCl, H2S, dust, heavy metals and solid waste. The models validation was made by comparing the calculated results with experimental data given by the industrial sites. Furthermore, the maturity of the models was tested through simulations using data coming from the "benchmark" data base defined in the frame of ULCOS project (Ultra Low CO2 Steelmaking).Through the models simulation, it was proved that this methodological framework assures the total control of mass and heat balances of the system which is difficult to achieve when using only data from industry and/or literature. However, the fact that the emissions calculated within the models are based on physical-chemical considerations gives a strong credibility to the life cycle inventory
Lambert, Charlène. « Simulation et optimisation énergétique de procédés agroalimentaires dans un logiciel de génie chimique. Modélisation du séchage convectif d'aliments solides et application à une sucrerie de betteraves ». Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLA004.
Texte intégralTo face recent European regulations, the food industry has a critical need for IT tools to simulate their entire factory to reconcile industrial data and optimize energy consumption. Such software exist in the field of chemical engineering. They are limited to mixtures of gases and liquids whose thermo-physical properties can be correctly predicted by thermodynamic models. To date, no commercial software is able to simulate most food unit operations and calculate the required thermophysical properties of foods, especially solid foods. A first part of this Ph.D. is dedicated to the development of a model of hot air drying of solid food. This model is being added to the ProSimPlus® unit operation module database. It has been validated in the laboratory scale for the drying of 4 products of different compositions and geometries. Its simulation time is significantly higher than the one of the other modules of ProSimPlus®. To overcome this issue, an innovative method of drying model reduction has been developed. To facilitate the characterization work of a new product, a new and rapid method for identifying the apparent diffusivity of water by a reverse approach was also developed. A second part of this PhD focuses on the simulation and energy optimization of a sugar beet factory, in collaboration with V.E.R.I. All the unit operations of the factory were modeled with ProSimPlus® using only modules of -food non-specific- unit operations. Data reconciliation has been performed and deviation between simulated and industrial data were below 1 %. Energy optimization of the sugar factory was performed by combining thermal and exergy analyses. In this study, technical solutions were proposed to significantly reduce the total irreversibility, the cold utility requirement and the mass flow-rate of high pressure steam supplying the factory
Heidari, Fariba. « Boom pétrolier et syndrome hollandais en Iran : une approche par un modèle d'équilibre général calculable ». Thesis, Nice, 2014. http://www.theses.fr/2014NICE0025/document.
Texte intégralIran as a country dominated by oil exports offers unique insights and rich rewards considering its economic and socio-political environment. Although according to a resource-based analysis this economy has the potential of being the world's 20th strongest economy because of its rich reserves in minerals and other natural resources alongside with country's geo-strategic position. It really seems strange and unbelievable how Iran can remain underdeveloped while having so many rare resources highly appreciated by the rest of the world. How we can explain this incoherence? The classic economic model describing Dutch Disease was developed by the economists W. Max Corden and J. Peter Neary in 1982. The so-called "Dutch Disease" as an economic concept explains the seeming relationship between natural resource abundance in a country and decline in other economic sectors specially manufacturing. This theory reveals that an increase in revenues from natural resources will de-industrialize the economy by raising exchange rate, which makes manufacturing sectors to become less competitive. The primary purpose of this paper is to determine if Iranian economy is suffering from this problem and if so what will be the impact of this issue on different sectors economy of Iran. In this paper, using an applied general equilibrium model, and not partial equilibrium model, we analyze Dutch disease in Iranian economy. We use the model that has been made by Dr Lofgren as a base and extend and adjust it for Iran economy. In order to solve the general equilibrium pattern numerically, GAMS software package can be used which is a powerful tool for solving linear and nonlinear equations
Attaya, Heger. « Le Marché des logiciels : une confrontation entre logiciels propriétaires, libres et piratés ». Thesis, Paris 13, 2014. http://www.theses.fr/2014PA131029.
Texte intégralPublishers of proprietary software are confronted both by the onset of piracy practices and free/open software. So far, the obstacles faced by proprietary software have been presented in the literature by means of two distinct approaches :(i) the piracy/proprietary software (illicit competition), or (ii) the open source/proprietary software (licit competition) standpoints. In this thesis we propose an alternative approach of the software market, which focuses on the coexistence of competitive forces piracy practices and open software. The three forces are supported by di_erent actors, to which we add the new one of open hardware that consolidated the position of free software on the market. The new approach distinguishes also between sophisticated active pirates producers and casual passive pirate users. We emphasized that it is di_cult to distinguish between hackers and pirates, as piracy practices are sometimes tolerated by the market. Using an econometric and mathematics model we show the impacts that one in_icts over the other. The mathematical model investigates how changes in the _rm's anti-piracy policya_ect the number of pirates users, given that the free software network size increases if pirates become free software users. The proposed econometric model shows that government policies in favour of open source software and adoption of Linux by individuals tends to decrease software piracy. A majorempirical result concerns the emerging and developing countries where policies in favour of free software can in some speci_c cases reduce piracy
Mahut, Fabien. « Intégration des approches PLM et SLM pour le développement et la gestion des Systèmes Produit-Service en contexte automobile : proposition d’un cadre méthodologique ». Thesis, Compiègne, 2019. http://bibliotheque.utc.fr/EXPLOITATION/doc/IFD/2019COMP2473.
Texte intégralThis research work is exploring the development and management of Product-Service Systems. These new integrated offers go along with specific issues which challenge the current product development strategies. Analyzing the academic literature on this matter, this work focuses on methodological frameworks for the development of PSS offers. The first level of these frameworks is about engineering approaches considers Service Lifecycle Management (SLM) and Product Lifecycle Management (PLM) interactions. The second level is about specific systems or PSS development processes and methods. The third and last level challenges the definitions of a PSS model. Fed by this review, this work provides a coherent proposal for PSS development across these three levels, qualified by 7 analysis criterias. On the first level, a detailed PLM-SLM interaction scheme is proposed. It supports a development process on the second level, alongside a PSS model based on FBS and result-resource-process triplet as a matter for service adequate description. This proposal has been experimented through two study cases. The first one, about an existing and mature PSS, enabled the development of a quality management tool. The second, about the development of a connected diagnostic PSS enabled to strengthen the illustration of the proposal for its adoption
Payen, Aurore. « Importance de la temporalité dans les phénomènes de propagation. Une illustration sur des échanges d'animaux d'élevage ». Electronic Thesis or Diss., Sorbonne université, 2018. http://www.theses.fr/2018SORUS247.
Texte intégralDisease spread among agricultural premises is greatly enhanced by cattle trade movements. Preventing spreading is a key issue for economical issues, for instance to prevent trade restrictions, but also for public health. Indeed, many animal diseases affect human beings, such as bovine tuberculosis. Tracing cattle trade movements is aiming at detecting the sources of infection, and thus, helps fighting against disease spread. Accessing databases recording cattle trade movements allows to study the structure and dynamic of the exchanges. To do so, methods developed for Social Network Analysis are more and more adapted and use for these purposes. The aim of this work is to use temporal models and methods to study cattle trade movements. As the development of temporal networks is relatively recent, few analyzes using these methods have been conduct on cattle trade data. Thus, contributions are twofold in this work: taking part to the development of analysis tools of temporal networks, and then, deducting potential ways of enhancement to control and fight against disease spread among holdings
Pham, Anh Thu. « Caractérisation aéraulique et thermique au sein d'un empilement de produits dégageant de la chaleur : application au cas des palettes de fromage ». Thesis, Paris, Institut agronomique, vétérinaire et forestier de France, 2019. http://www.theses.fr/2019IAVF0010/document.
Texte intégralCheese, like any fresh product, must be kept at a low temperature throughout the cold chain. A particularity of soft cheeses (Camembert, for example) is that they generate a significant amount of heat due to the respiration of the microorganisms. From a thermal point of view, cold air must flow within a cheese pallet to remove the heat released in order to achieve better production temperature control. From an airflow point of view, heat generated by the product induces natural convection inside the pallet. Several convection modes are therefore present: the forced convection imposed by the fans of the cold room around the pallet and the mixed convection, combination of forced and natural convection, inside the pallet. This therefore increases the complexity of the airflow. The mixed convection regime appears mainly at low fan speed which is often the case during storage. In addition, the system is influenced by many parameters: the orientation of the pallet, the opening area of the cartons, the blowing speed, the heat flux...The aim of the PhD is to provide inner knowledge on air flows and heat transfer within pallets of heat-generating products with low ventilation. This knowledge also aims to answer industrial problems. The PhD’s results should contribute to improve the design of vented cheese packaging and palletizing methods, which is currently done empirically. It should also be noted that the scientific topic addressed in this project related to aerodynamic and thermal interactions between forced and natural convection around and within the pallet has applications in other areas such as the cooling of electronic circuits.The PhD consists of two main parts: an experimental and a numerical study. In the experimental approach, a full scale pallet was built in which the products were replaced by plaster blocks inserted with heating resistance to simulate the heat flow generated by cheese. The experiments were carried out in a controlled temperature and air velocity room for two air inflow velocities: 0.31 and 0.73 m.s-1, three heat fluxes: 0.05 W, 0.15 W and 0.30 W per product (0.25 kg) and two orientations of the palette. The use of a laser Doppler velocimetry (LDV) and a hot-wire anemometer allowed characterizing airflows (velocity profiles, air flow rate in the vent holes) according to the air inflow velocity and the heat flux. The implementation of 200 thermocouples distributed throughout the experimental set-up also made it possible to obtain the temperature levels of the air and the products within the pallet according to these same parameters.The numerical study was performed by two approaches: a detailed model by computational fluid dynamics (CFD) with several millions of elements and a zonal model (about twenty zones) assimilating the system to a hydraulic network. Both models were validated using experimental data. The CFD gave complement information which is not accessible by the experimental measurements, which facilitated the understanding of the phenomena. The zonal approach, by its simplicity of use and its low computing time is more suitable for an industrial use
Rougieux, Paul. « Modelling European Forest Products Consumption and Trade in a Context of Structural Change ». Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0004/document.
Texte intégralForests in the European Union grow by 1.2 billion m³ per year. Half of this volume stays in the forest, in particular for sustainable forest management purposes. The other half flows into three industrial sectors: wooden material, paper products and wood energy. These industrial product flows are set into motion and paid for by diverse final consumers. Since 2000, consumption is undergoing important structural changes which cause large disturbances in material, paper and fuel flows. To predict the impact of these changes, economists model relationships between raw material supply, final products demand, prices, production and international trade. This thesis uses panel data econometrics to estimate parameters of empirical models. An introductory chapter sets the policy context of forest resources and forest products of interest at a macroeconomic level. Then I review major forest sector models and I focus on issues encountered while estimating parameters of demand models. A second chapter investigates the potential impact of a trade agreement between the EU and the US on the forest sector. We found that total welfare would increase in the region of the agreement, in addition the agreement benefits more to consumers than to producers. Results show that third party countries are impacted by the agreement too, which highlights the importance of using a global trade model in analysing the impacts of the agreement. In a third chapter I estimate revenue and price elasticities of demand for forest products on a panel of European countries. I deal with non stationarity issues and estimate demand elasticities within cointegrated panels. I demonstrate that revenue elasticities of demand are lower than previous estimates from the literature. Simulations using these robust elasticities in a forest sector model, show a lower demand over a 20 years time horizon. In a fourth chapter, I analyse structural changes in paper products consumption. For this purpose, I use a panel threshold model to estimate the relationship between information technology use and paper products consumption: newsprint, printing and writing paper. I show how paper demand elasticities depend on internet penetration in the population. Thresholds occur once a majority of the population has access to the internet. After the threshold, coefficients between paper consumption and its explanatory variables revenue and price become smaller in absolute terms or even change sign. Based on projections of the number of internet users per country, paper consumption projections could be updated with this type of thresholds models. From a policy perspective, lower demand for graphics paper would free resources and make them available for innovative forest products and services
Alfonso, Medina Hugo Leonardo. « Caractérisation et modélisation des assemblages multi-matériaux sous sollicitations mixtes quasi-statiques pour la conception des structures automobiles ». Thesis, Brest, 2016. http://www.theses.fr/2016BRES0118/document.
Texte intégralNowadays, the emissions of CO2 due to the use of automobiles have reached critical levels causing global warming and health problems. In order to reduce these emissions, the French automotive industry has decided to reduce the car weight by means of the use of lighter materials such as composite materials. However, the classical joining techniques are not adapted to assembly these new materials to the structure of the car (aluminum and steel alloys). Therefore, the characterization and modeling of new joining techniques of dissimilar materials is a problem that has been treated in the current study.Four different joining techniques of dissimilar materials (metal/composite) have been studied: (i) stud bonding, (ii) laser welding, (iii) self-pierce riveting and (iv) adhesive bonding systems. Traditional lap-shear and cross-tension tests were used to characterize the first two joining techniques. Then, a new characterization test based on a modified Arcan device has been proposed to analyze the behavior of self-piercing rivet and adhesive bonding systems. Among all the four tested techniques, adhesive joints have been selected as the most adapted technique according to the requirements of the industry. Therefore, modified Arcan tests have been performed in order to determine the behavior of the adhesives of the study (Betamate1822 and Sikapower498). These tests were then used to propose and identify a new 3D non-linear viscoelastic spectral model. The identification procedure of the material parameters is only based on three multilevel creep tests, which permits the rapid dimensioning of adhesively bonded structures. Finally, the proposed behavior law was validated by the good concordance between the numerical predictions and the experimental curves of monotonic tests at different loading rates and increasing cyclic tests.The current study was developed in the framework of an automotive project. Nevertheless, the conclusions and prospects of the study can be extrapolated to other interesting fields
Trouvain, Guillaume. « Evolution des outils de simulation rapide du procédé de fabrication du pneumatique avant cuisson ». Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22546/document.
Texte intégralThis thesis deals with fast simulation tools used to manufacture of a tire. The goal is to predict the displacement and position of the components of a tire taking into account the deformations induced by the associated mechanical actions. This work is based on the implementation of an algorithm for modeling the inflation of a tool and the development of a deformation model in order to compute the deformation of geometric shapes taking into account different mechanical properties. The algorithm to model the inflation of the tool is based on the theory of inextensible membranes and its industrialization is validated for standard sizes of tires. Mass-Spring method is used to achieve the deformation of geometric shapes in order to compute deformation in real time. In this work, this method is suitable for materials of a tire from geometric and mechanical characterizations validated by comparison with FEM. To conclude, the developed modelization allows a description for each step of the manufacturing process
David, Antoine. « Étude des vibrations des réseaux de transport de gaz dans l'industrie de l'aluminium ». Thesis, Compiègne, 2016. http://www.theses.fr/2016COMP2277/document.
Texte intégralRectangular duct used for gas transport ductwork, especially in the aluminium industry, are excited by the internal flow. This thesis seeks to understand what are the phenomena involved in the vibration of the gaz transport ductwork. Firstly, we present a semi-analytical model of a homogeneous rectangular duct based on the coupling of 4 plates. This modeling allow us to define the duct modal characteristics and is validated by using both experimental and numerical (FEM) ways. Secondly, we applied aeroacoustic and aerodynamic excitations to our duct in order to determine which are the main contributions. Comparisons between numerical and experimental results, in the case of a straight duct highlight that aeroacoustic sources are predominant. The same trends are found with a bend configuration with few changes close to the band where aerodynamic sources seems to be predominant also. Finally, we apply our model to a large rectangular duct used in the aluminium industry. We note that the model gives good trends and highlights again the importance of the aeroacoustic contributions. Some reflexions about how to reduce the vibration levels by changing geometrical parameters are given at the end
Iosif, Ana-Maria. « Modélisation physico-chimique de la filière classique de production d'acier pour l'analyse de l'Inventaire du Cycle de Vie ». Thesis, Vandoeuvre-les-Nancy, INPL, 2006. http://www.theses.fr/2006INPL074N/document.
Texte intégralThis work was devoted to a new methodological framework, which combines the Life Cycle Assessment (LCA) method and the process simulation software (Aspen Plus), in order to improve the quality of data used for carrying out the Life Cycle Inventory (LCI) of the classical steelmaking route. The new approach adopted in the present work, is to carry out the inventory of the defined system via simplified physical-chemical models. Using Aspen Plus software, we have developed simplified physical-chemical models for each of the subsystem defined by the boundaries of the classical steelmaking route: coking plant, sintering plant, blast furnace, basic oxygen furnace and hot rolling. The modelling strategy was based on physical and chemical considerations and on the experimental observations made on an industrial and/or a pilot scale for each subsystem.The models allow for calculation of the principal pollutants evolved by the system such as CO2, CO, NO, SO2, COV, HCl, H2S, dust, heavy metals and solid waste. The models validation was made by comparing the calculated results with experimental data given by the industrial sites. Furthermore, the maturity of the models was tested through simulations using data coming from the "benchmark" data base defined in the frame of ULCOS project (Ultra Low CO2 Steelmaking).Through the models simulation, it was proved that this methodological framework assures the total control of mass and heat balances of the system which is difficult to achieve when using only data from industry and/or literature. However, the fact that the emissions calculated within the models are based on physical-chemical considerations gives a strong credibility to the life cycle inventory