Este trabalho aborda a estratégia na relação com os fornecedores em empresas de alta tecnologia e produtos complexos. Para tanto, foi tomado o caso da fabricação de aeronaves produzidas pela Embraer, que se destacou pela sua estratégia de parceria com seus fornecedores, principalmente na linha dos produtos das Famílias ERJ 145 e E-Jets. No entanto, na sua última linha de produtos, o que se percebe é uma estratégia diferenciada no seu modo de se relacionar com seus fornecedores, o que levou à questão da pesquisa. O presente trabalho discute as opções de relacionamento com fornecedores, do simples fornecimento ao compartilhamento de investimentos e riscos, e as racionalidades subjacentes. As técnicas utilizadas para elaborar o trabalho foram observação direta e pesquisa em dados secundários, revistas especializadas, web sites vinculados à indústria aeronáutica e associações, artigos acadêmicos e documentos da empresa. Além disso, foram conduzidas entrevistas semi-estruturadas, com empregados e ex-empregados da empresa, inclusive diretores. Os resultados mostram que, apesar de as grandes empresas como Boeing e Airbus terem adotado o modelo de parceria de risco desenvolvido pela empresa em estudo, esta hoje adota um modelo híbrido, com foco em lições anteriormente aprendidas na relação com fornecedores. / This paper discusses the strategy for relationship with the suppliers at high-tech and complex product companies. Therefore, the case studied was the manufacture of aircraft produced by Embraer and its unique strategy of partnering with suppliers, mainly when dealing the products of the ERJ145 and E-Jets families. In the company\'s latest line of products a particular strategy is observed in terms of relationship with suppliers, which led to our research question. This paper discusses the options of supplier relationships, from simple supply to shared investments and risks, and the rationales that underly them. The techniques used in this study were direct observation and research on secondary data, journals, websites linked to the aircraft industry and associations, academic papers, and the company\'s documents. In addition, semi-structured interviews were conducted with both current and former employees. The results show that despite the fact that large companies like Boeing and Airbus use the partnership model of risk adopted by the company under study, Embraer is currently adopting a hybrid model focusing on lessons learned earlier in its supply chain.

Uniões por prendedores são elementos amplamente utilizados na indústria aeronáutica para a união de partes constituintes da aeronave. Contudo, devido à sua geometria e aos carregamentos sofridos, estes elementos estão frequentemente sujeitos a falhas por fadiga. Assim, para um projeto e dimensionamento bem executado dessas juntas, é necessário conhecer seu comportamento mecânico e o campo de tensões ao qual estão sujeitas. O método dos elementos finitos certamente atende a estas necessidades; porém, o uso de elementos sólidos tridimensionais para a representação destas uniões pode levar a análises demasiadamente demoradas e custosas, sendo desejável o uso de modelos mais simplificados. Nesse trabalho, juntas de topo assimétricas são modeladas pelo método dos elementos finitos, utilizando tanto elementos sólidos tridimensionais quanto elementos de casca, com o objetivo de encontrar um modelo relativamente simples que apresente resultados satisfatórios e requeira um menor tempo de solução. Os resultados numéricos obtidos são comparados com resultados experimentais, que utilizam extensômetros e fotoelasticidade. / Riveted joints are structural elements widely used in the aeronautic industry to connect different parts of the aircraft. However, due to their geometry and working load, they are frequently subjected to fatigue failure. Therefore, to a well executed project of this type of joint, it is necessary to understand the mechanical behavior and the stress field to which they are subjected. The finite element method can certainly answer those needs; however, the use of tridimensional elements to represent this type of joint can lead to time consuming and expensive analysis, being desirable the use of simpler models. In this work, asymmetric butt joints are modeled using the finite element method using both, tridimensional and shell elements, with the objective of finding a model that provides satisfactory results at smaller solution time. The numerical results obtained are compared with experimental results using strain gage and photoelastic procedures.

La réparation des composants en alliages légers est un processus clés dans le domaine de l’aéronautique. Ces alliages sont abondamment utilisés dans les constructions aéronautiques notamment pour des composants à forte valeur ajoutée. Leur utilisation combinée à une optimisation de la conception des pièces permet de disposer de produits satisfaisants aux exigences de masse, de coût et de performances. Cependant l’utilisation de ces pièces est limitée dans le temps car divers endommagements peuvent survenir aussi bien lors de leurs manipulations que lors de leurs utilisations en service. Des solutions de retouches existent mais ne permettent pas toujours de redonner leur intégrité aux zones affectées. Ces limitations sont à l’origine d’un fort taux de rebut parmi les pièces à forte valeur ajoutée.Les multiples avantages du procédé Cold Spray en font un candidat idéal pour la projection de revêtements adaptés aux composants en alliages légers mis en oeuvre en aéronautique, que ce soit dans une logique de protection, de retouche ou de réparation. Il s’agit de reconstruire la pièce par un revêtement aux caractéristiques les plus proches possibles de celles du matériau de base. Ce travail de thèse consiste à optimiser l’ensemble des paramètres du procédé de projection dynamique à froid (Cold Spray) pour plusieurs couples substrat-revêtement combinant différents alliages d'aluminium, de magnésium et des composites à matrice métallique à base aluminium.La première étape a consisté à optimiser les paramètres principaux du procédé Cold Spray afin de s’affranchir du phénomène de colmatage pouvant intervenir au sein de la section divergente de la buse de projection. Ce phénomène a pour effet de diminuer la vitesse des particules, les revêtements obtenus devenant alors assez poreux. Une étude s’est ensuite focalisée sur l’optimisation de l’adhérence des couples substrats-revêtements. Il a été démontré le rôle primordial de la préparation de surface dans l’adhérence des revêtements où l’ancrage mécanique apparaît prépondérant. Enfin, une étude originale a été conduite pour mettre au point une méthodologie pour recharger localement une zone défectueuse sans avoir à recouvrir toute la surface du substrat. Une programmation hors ligne du robot a été employée afin de recouvrir deux types de défaut pré-usinés sur des blocs d’alliage d'aluminium. Les résultats sont satisfaisants avec des gains en temps de projection et des dépôts sans défaut après usinage. / The repair of light alloy parts is a major issue in aeronautics. Aluminum alloy and magnesium alloy are widely used in aircraft parts, especially for high value-added components. Their use combined to optimizing design allows to have satisfactory products meeting mass, cost and performance requirements. However, like any other life-limited components, various damages can occur not only during handling procedure but also while operating. Rectification solutions exist but do not always comply with requirements. These limitations entail high scrap rates among high value-added parts.The various advantages of the cold spray process make it an ideal candidate for suitable coatings for light alloy aircraft components as protective, retouching or repair methods. The aim is to rebuild the damaged part by a coating whose characteristics are closest to those of primary materials. This thesis proposes to optimize different cold spray parameters for several substrate-coating pairs combining different aluminum alloys, magnesium alloys and aluminum alloy-based metal matrix composites.The first step was to optimize the main parameters of cold spray process to prevent clogging phenomenon that may occur in the expansion part of the nozzle. It decreases particle kinetics and promotes porous coating. Then, adhesion optimization of substrate-coating couples was investigated. The substrate surface preparation is a key factor on coating adhesion, where the mechanical anchoring appears essential. Finally, an innovative study was conducted to develop a method to cover locally surface defects. Offline programming trajectories were used to fill up two kinds of pre-machined defaults on aluminum alloy blocks. Results are in good agreement with spray time savings and defect free coatings after machining.

ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / Systems using single carrier modulations for flight test transmissions perfectly fit noisy and time selective channels. However, the densification of the airport environment now makes the aero channel also frequency selective due to multiple reflections on surrounding buildings, especially while taxiing and taking off. Obviously, this has a direct consequence on hardware resources and user data rates. In such a context, COFDM represents an appealing solution thanks to its inherent robustness to multipath fading channels. But a direct application of an off-the-shelf COFDM standard is not straightforward as these standards are designed for specific channels whose characteristics are quite different from the aero one. That is why we made an experiment at Toulouse-Blagnac airport to jointly sound the channel and qualify a COFDM waveform. This paper then describes the construction of the waveform and the results of the channel sounding. From this, different standard paradigms are compared.

Why are some high-technology sectors trans-nationally integrated while others are sites of interstate competition? This dissertation explores this question through a comparison of China-U.S. relations in two strategic, high-technology sectors: civil-commercial aircraft manufacture and civil-commercial spacecraft manufacture. Between 1989 and 2009, China-U.S. relations took strikingly different trajectories in these two sectors. In the aircraft sector, the two countries’ industries traded and integrated their activities and their civil agencies cooperated. By contrast, in the space sector, their industries did not trade or integrate, their civil agencies did not cooperate, and the two countries engaged in a form of technological competition. The divergent trajectories taken by China-United States relations in these two sectors are puzzling because both sectors present similar incentives and disincentives for both transnational integration and interstate competition. Theories of international relations do not fully explain this sectoral variation. This research indicates that this variation is traceable to underlying differences in how specialists in each sector, including technical and policy experts, implicitly reason about and represent technologies in general. In both countries, the air and space specialist communities each hold distinct understandings of the relationship between humans and technology. Performing representational practices that reflect these distinct assumptions, aeronautic and space specialists discursively constitute each sector and its technologies as distinct objects of policy, requiring different forms of state action. In air, these include policies adopted by both countries to enhance bilateral trade, industrial partnership, and technical cooperation. In space, these include measures to inhibit bilateral trade and cooperation while preparing for a coming bilateral confrontation.

Why are some high-technology sectors trans-nationally integrated while others are sites of interstate competition? This dissertation explores this question through a comparison of China-U.S. relations in two strategic, high-technology sectors: civil-commercial aircraft manufacture and civil-commercial spacecraft manufacture. Between 1989 and 2009, China-U.S. relations took strikingly different trajectories in these two sectors. In the aircraft sector, the two countries’ industries traded and integrated their activities and their civil agencies cooperated. By contrast, in the space sector, their industries did not trade or integrate, their civil agencies did not cooperate, and the two countries engaged in a form of technological competition. The divergent trajectories taken by China-United States relations in these two sectors are puzzling because both sectors present similar incentives and disincentives for both transnational integration and interstate competition. Theories of international relations do not fully explain this sectoral variation. This research indicates that this variation is traceable to underlying differences in how specialists in each sector, including technical and policy experts, implicitly reason about and represent technologies in general. In both countries, the air and space specialist communities each hold distinct understandings of the relationship between humans and technology. Performing representational practices that reflect these distinct assumptions, aeronautic and space specialists discursively constitute each sector and its technologies as distinct objects of policy, requiring different forms of state action. In air, these include policies adopted by both countries to enhance bilateral trade, industrial partnership, and technical cooperation. In space, these include measures to inhibit bilateral trade and cooperation while preparing for a coming bilateral confrontation.

Produits industriellement dès 1910, les duralumins (alliages Al-Cu-Mg) sont les premiers alliages d'aluminium à durcissement structural ayant permis le développement de l'aéronautique. Bien que les alliages Al-Zn-Cu de la famille 7xxx et les matériaux composites soient aujourd'hui majoritaires dans la construction des avions, ces alliages Al-Cu-Mg de la famille 2xxx restent un matériau de référence pour les structures aéronautiques. Cependant, même s'il est un produit industriel récent et largement utilisé, avec une grande production de documents écrits, il existe une perte d'informations liée à la politique d'archives appliquée par les industriels. Cette perte d'information touche particulièrement les données physico-chimiques des matériaux utilisés pour la construction des avions mais aussi l'explication des choix techniques des avionneurs. La rénovation du Breguet 765 Sahara n°504 64-PH aux Ailes Anciennes Toulouse est une opportunité d'étudier les duralumins aéronautiques de la fin des années 1950. Il est possible de récupérer les pièces déposées et remplacées avant qu'elles ne soient jetées et définitivement perdues avec les informations qu'elles contiennent. En comparant l'analyse en laboratoire de ces matériaux arrivés jusqu'à nous avec les documents d'archives et la documentation actuelle, il est possible d'entreprendre un retour sur expérience. Nous pouvons envisager de comparer ce qui a été réalisé avec ce qui a été initialement prévu lors de la conception de l'avion et de compléter les données connues de ces matériaux avec les techniques d'analyses métallurgiques actuelles. Ces alliages peuvent également constituer une première référence des duralumins aéronautiques des années 1950 et contribuer à l'étude de l'évolution sur de grandes échelles de temps des propriétés mécaniques par rapport aux valeurs minimum exigées du constructeur. / Industrially produced since 1910 and used for the construction of Breguet XIV in 1916, the duralumins (Al-Cu-Mg alloys) are the first age-hardening aluminum alloys that were at the origin of the aeronautics development. Although Al-Zn-Cu alloys of the 7xxx family and composite materials are more widely used today, these Al-Cu-Mg alloys of the 2xxx family remain a reference material for aircraft structures. However, although it is an industrial material, with a large production of written documents, the archiving policy applied by manufacturers causes a loss of information. There is thus a difficulty to retrieve pertinent chemical and physical data of material used in aircraft construction, but also to understand the choices made about the material and process used by the manufacturers. The renovation of the Breguet 765 Sahara n°504 64-PH by the association Ailes Anciennes Toulouse is an opportunity to study aeronautical duralumins of the late 1950s. It is possible to recover elements need to be replaced before they are permanently lost, with the information contained therein. By comparing laboratory analysis with archival and current literature, it is possible to give a feedback on these ancient materials. We can compare what was done with what was originally planned in the design of the aircraft and complete the known data of these materials with current metallurgical technical analysis. These alloys can also be a first reference for aeronautical duralumins of the 1950s and contribute to the study of the long-term evolution of mechanical properties compared to minimum values ??required by the manufacturer.

Uniões por prendedores são elementos amplamente utilizados na indústria aeronáutica para a união de partes constituintes da aeronave. Contudo, devido à sua geometria e aos carregamentos sofridos, estes elementos estão frequentemente sujeitos a falhas por fadiga. Assim, para um projeto e dimensionamento bem executado dessas juntas, é necessário conhecer seu comportamento mecânico e o campo de tensões ao qual estão sujeitas. O método dos elementos finitos certamente atende a estas necessidades; porém, o uso de elementos sólidos tridimensionais para a representação destas uniões pode levar a análises demasiadamente demoradas e custosas, sendo desejável o uso de modelos mais simplificados. Nesse trabalho, juntas de topo assimétricas são modeladas pelo método dos elementos finitos, utilizando tanto elementos sólidos tridimensionais quanto elementos de casca, com o objetivo de encontrar um modelo relativamente simples que apresente resultados satisfatórios e requeira um menor tempo de solução. Os resultados numéricos obtidos são comparados com resultados experimentais, que utilizam extensômetros e fotoelasticidade. / Riveted joints are structural elements widely used in the aeronautic industry to connect different parts of the aircraft. However, due to their geometry and working load, they are frequently subjected to fatigue failure. Therefore, to a well executed project of this type of joint, it is necessary to understand the mechanical behavior and the stress field to which they are subjected. The finite element method can certainly answer those needs; however, the use of tridimensional elements to represent this type of joint can lead to time consuming and expensive analysis, being desirable the use of simpler models. In this work, asymmetric butt joints are modeled using the finite element method using both, tridimensional and shell elements, with the objective of finding a model that provides satisfactory results at smaller solution time. The numerical results obtained are compared with experimental results using strain gage and photoelastic procedures.

Este trabalho aborda a estratégia na relação com os fornecedores em empresas de alta tecnologia e produtos complexos. Para tanto, foi tomado o caso da fabricação de aeronaves produzidas pela Embraer, que se destacou pela sua estratégia de parceria com seus fornecedores, principalmente na linha dos produtos das Famílias ERJ 145 e E-Jets. No entanto, na sua última linha de produtos, o que se percebe é uma estratégia diferenciada no seu modo de se relacionar com seus fornecedores, o que levou à questão da pesquisa. O presente trabalho discute as opções de relacionamento com fornecedores, do simples fornecimento ao compartilhamento de investimentos e riscos, e as racionalidades subjacentes. As técnicas utilizadas para elaborar o trabalho foram observação direta e pesquisa em dados secundários, revistas especializadas, web sites vinculados à indústria aeronáutica e associações, artigos acadêmicos e documentos da empresa. Além disso, foram conduzidas entrevistas semi-estruturadas, com empregados e ex-empregados da empresa, inclusive diretores. Os resultados mostram que, apesar de as grandes empresas como Boeing e Airbus terem adotado o modelo de parceria de risco desenvolvido pela empresa em estudo, esta hoje adota um modelo híbrido, com foco em lições anteriormente aprendidas na relação com fornecedores. / This paper discusses the strategy for relationship with the suppliers at high-tech and complex product companies. Therefore, the case studied was the manufacture of aircraft produced by Embraer and its unique strategy of partnering with suppliers, mainly when dealing the products of the ERJ145 and E-Jets families. In the company\'s latest line of products a particular strategy is observed in terms of relationship with suppliers, which led to our research question. This paper discusses the options of supplier relationships, from simple supply to shared investments and risks, and the rationales that underly them. The techniques used in this study were direct observation and research on secondary data, journals, websites linked to the aircraft industry and associations, academic papers, and the company\'s documents. In addition, semi-structured interviews were conducted with both current and former employees. The results show that despite the fact that large companies like Boeing and Airbus use the partnership model of risk adopted by the company under study, Embraer is currently adopting a hybrid model focusing on lessons learned earlier in its supply chain.

Ces dernières décennies ont été caractérisées par une évolution massive de l'Internet sur tous les plans, couvrant les applications et les technologies réseau. En conséquence, de nouveaux besoins pour les applications et de nouvelles contraintes réseaux apparaissent ; rendant ainsi les protocole (TCP et UDP notamment) de moins en moins efficaces, et plusieurs nouveaux protocoles ont été proposés. Cependant, à cause de plusieurs limites architecturales de la couche Transport, ces nouveaux protocoles n'ont pas été déployés.Partant de ce constat, le travail effectué dans cette thèse porte sur la proposition et la réalisation d'une architecture pour la couche Transport, orientée services et basée composants, dotée de capacités d'extensibilité et d'autoadaptation vis-à-vis des évolutions du contexte applicatif et réseau. La solution proposée repose, d'une part, sur un faible couplage entre les éléments extérieurs (applications et systèmes) et la couche Transport, ainsi qu'entre les composants internes de l'architecture. D'autre part, elle se base sur des modèles et des algorithmes lui permettant de détecter et de prendre en compte les évolutions du réseau ou des applications, et d'adapter son comportement en conséquence. Une implémentation complète de la solution est proposée et testée dans un cadre de communications aéronautiques par satellite. L'objectif étant la gestion de la transition des protocoles spécifique au monde aéronautique vers les protocoles de l'Internet, ainsi que la gestion, au niveau Transport, des liens physiques hétérogènes. Les tests démontrent la faisabilité d'une telle architecture extensible et autonome, les gains en performance qu'il est possible d'obtenir, et les coûts qui en résultent. / The recent decades are characterized by an important evolution of the Internet at all planes, covering applications and network technologies. This evolution results on new applications requirements and new networks constraints making classical protocols (TCP and UDP typically) less and less suitable. Consequently, many new more efficient protocols have been proposed. However, due to several limitations of the actual Transport layer, these new protocols have not been deployed.From this statement, the work presented in this thesis is about the proposition and the realization of an architecture for the Transport layer, including extensibility and auto-adaptability capabilities regarding the evolution of application and network context. The proposed solution is based on low-coupling between, in a part, the Transport layer and the external actors (applications and systems), and in the other part between the internal component of the architecture. In parallel, the architecture is based on models and algorithms for detecting and taking into account the evolution of networks and applications, and adapt it behavior consequently. A complete implementation of the solution is proposed and evaluated in the context of aeronautical communications by satellite. The aim is the management of the transition phase of the aeronautical network to the Internet protocols suite, and the management of the heterogeneity of the different physical links. The tests demonstrated the feasibility of such extensible and autonomic architecture, the performances gains which can be obtained, and the resulting cost.