Yes / Objective: Skill mix has been established as one method of maintaining imaging service delivery, with vertical and horizontal substitution of roles and tasks. Assistant practitioners (APs) have been undertaking limited imaging practice for almost two decades, but there remains a paucity of evidence related to the impact of their roles. Methods: This article reports on an electronic survey of individual APs within the NHS in the UK to explore utilisation, role scope and aspirations. Results: Responses were analysed from APs (n = 193) employed in 97 different organisations across the UK. The majority work in general radiography or mammography, with very few responses from other imaging modalities. Training routes varied across modalities, with most achieving Band 4 under Agenda for Change on completion of education. Limitations on practice vary between organisations and modalities, with many reporting blurring of the radiographer-AP boundary. Many aspire to continue their training to achieve registrant radiographer status, although there were clear frustrations from respondents over the lack of overt career prospects. Conclusion: Integration of the role into imaging department practice does not appear to be universal or consistent and further research is required to examine the optimal skill mix composition. Advances in knowledge: Skill mix implementation is inconsistent across modalities and geography in the UK. Opportunities for further workforce utilisation and expansion are evident.

As altas exigências que impõe o mercado globalizado, a complexidade dos sistemas produtivos de manufatura atuais e os avanços na Tecnologia da Informação são fatos que resgatam a importância da Programação Detalhada da Produção para as empresas. A pesar de bastante consolidada e difundida, a abordagem clássica MRP / ERP não atende plenamente as necessidades em ambientes de produção intermitente. A Programação Detalhada da Produção com capacidade finita dos recursos, atualmente contemplada nos sistemas APS (Advanced Planning & Scheduling), constitui uma alternativa interessante para melhor cumprir prazos de entrega em ambientes com roteiros de produção complexos e produção make-to-order (MTO). O problema de pesquisa ora estudado contempla o ensino de modelos de Planejamento e Controle da Produção (PCP) em um ambiente de produção intermitente, com foco na Programação Detalhada da Produção e nos sistemas MRP e APS. Propõe-se um plano de ensino que busca apresentar e diferenciar essas abordagens. O plano contempla o uso de um caso didático A Fábrica de Skates. De uma forma lúdica, porém realista, o caso apresenta, nas suas cinco etapas, duas situações hipotéticas de uso de sistemas de programação. O primeiro, um MRP para planejamento da fábrica de skates e, no segundo, um APS utilizado pelo fornecedor de eixos. O plano foi aplicado pela primeira vez em uma turma de graduação do curso de Engenharia de Produção. Nesta dissertação, é apresentada uma descrição detalhada do caso didático, junto ao plano de ensino. A pesquisa verificou, mediante análise das atividades do caso e de um questionário de avaliação, a utilidade dos recursos elaborados, como também que as estratégias aplicadas ajudaram na aprendizagem. Nesta primeira aplicação, constatou-se também que a alta carga de trabalho dos alunos no semestre e o pouco peso dado à nota final do caso didático foram fatores que inibiram melhores resultados. Para futuras aplicações, o caso didático pode ser aprimorado: novas etapas contemplando outros assuntos importantes para a disciplina PCP e análise de alternativas para substituição dos softwares empregados são exemplos de melhorias. / The high standard of competition in global market, the complexity of current manufacturing systems and the advances in Information Technology highlight the importance of the detailed production scheduling. Although classical approaches such as MRP perform this function quite well in different situations, these systems do not perform well in make-to-order (MTO) production systems. The finite capacity scheduling currently embedded within the software called APS (Advanced Planning & Scheduling) is a more interesting approach to achieve better performance in meeting due dates in production environments with complex routings and MTO strategy. Thus, the problem addressed in this study concerns the teaching of Production Planning and Control (PPC) models for intermittent production, with focus on the detailed production scheduling using MRP and APS approaches. In order to that, a teaching plan is proposed to present and differentiate these approaches. It includes the use of an educational case study named \"The Skateboard Factory\". In a playful but realistic way, the case presents, in its five stages, two hypothetical situations of use of scheduling systems. First, an MRP approach for planning in the skateboard factory, and second, one APS approach used by the truck supplier. The teaching plan was first applied to an undergraduate degree Production Engineering program. In this dissertation, a detailed description of the educational case study, along with the teaching plan, is provided. The results achieved in the case study and the students evaluation attest to the usefulness of the resources designed, and also that the strategies applied really improved the learning process. In this first application, it was also observed that high workload and the little weight in the final grade of the case study inhibit better results. In future applications, the case can be enhanced to include new stages on other important issues of the PPC discipline and the replacement of the software used.

De nos jours, les caméras sont de plus en plus utilisées lors de missions spatiales ou en centrale nucléaire pour des missions d'observations (civiles ou militaires) et de surveillance (vérification du déploiement de panneaux solaires, opérations extravéhiculaires, accident nucléaire, site de stockage). L'environnement spatial, les réacteurs civils nucléaires ou les lieux de stockage de déchets radioactifs sont des milieux radiatifs qui peuvent très fortement perturber les composants électroniques et les systèmes. Dans ces environnements, les rayonnements ionisants dégradent les paramètres électriques des composants électroniques. La dose totale ionisante conduit à l'apparition d'un nombre significatif de charges dans les oxydes des matériaux constituant les composants électroniques, modifiant leurs propriétés électriques. Il en résulte qu'une exposition à la dose totale ionisante peut entraîner une défaillance partielle ou totale d'un composant voire d'un système électronique embarqué.Dans le cadre de cette thèse, nous proposons une méthode de régénération pour guérir les paramètres électriques dégradés par la dose totale ionisante de composants électroniques soumis aux rayonnements ionisants. Cette méthode consiste à appliquer des cycles de recuit isothermes à un composant électronique. Dans un premier temps, cette méthode est appliquée sur des transistors MOS, et une étude est menée sur l'impact des différents paramètres clés du recuit (polarisation, température, durée de recuit, pas en dose entre chaque recuit). Dans un second temps, nous nous intéressons à des composants plus intégrés et plus récents tels que des capteurs d'images de type CMOS APS. Nous montrons expérimentalement l'impact d'un recuit sur ce type de composant et enfin, nous adaptons la méthode de régénération pour l'appliquer à ces capteurs APS afin d'augmenter leur durée de vie. / Nowadays, cameras are more and more used in space missions or nuclear plant for observation (civil or military) and monitoring missions (checking the deployment of solar panels, extravehicular operations, nuclear accident, and area storage). The space environment, nuclear reactors or radioactive waste storage areas are radiative environments that can greatly disturb electronic components and systems. In these environments, ionizing radiation degrades the electrical parameters of electronic components. The total ionizing dose induces significant charge build-up in oxides, degrading the electrical properties of the materials of electronic devices. That can result in the loss of functionality of the entire electronic system.In this thesis, we propose a regeneration method to recover the electrical parameters degraded by total ionizing dose of electronic components subjected to ionizing radiation. In this method isothermal annealing cycles are applied to electronic devices. In a first step, this method is applied on MOS transistors, and a study is conducted on the impact of various key parameters of annealing (bias, annealing temperature, annealing time, dose step between each annealing). In a second step, we focus on components more integrated and newer such as CMOS APS image sensors. We experiment what is the impact of annealing on this type of component and finally, the regeneration method is modified to be suitable on these APS sensors to increase their lifetime.

Devido à grande pressão pela redução de estoques e prazos de entrega, concomitantemente com o aumento da variedade de produtos, o planejamento e controle da produção tem se tornado cada vez mais complexo e desafiador. Basicamente, essa atividade das empresas objetiva planejar e controlar o uso dos recursos produtivos, visando atender à demanda dos clientes. Tradicionalmente, a literatura tem abordado os sistemas MRP, KANBAN, OPT, mas um novo conjunto de soluções de sistemas de programação finita vem sendo crescentemente tratado. As empresas, na busca de aprimoramento para a atividade de PCP estão à procura de ferramentas de programação finita, também conhecidas como Advanced Planning and Scheduling (APS), a fim de melhorar o processo de gerenciamento de pedidos, incluindo quesitos como a determinação de prazos de entrega na etapa de negociação dos pedidos, programação efetiva dos pedidos firmes e controle da produção. Esta dissertação pretende verificar as necessidades e dificuldades da programação detalhada da produção, as barreiras de implantação e os benefícios dos APS. O método utilizado foi o levantamento survey nas empresas filiadas à Federação das Indústrias do Estado de São Paulo (Fiesp). Os resultados obtidos mostram que a programação detalhada da produção é uma atividade complexa para a maioria das empresas com estratégia de produção contra pedido (MTO), que estão direcionadas para aumento de desempenho estratégico. A grande maioria das empresas ainda utiliza o modelo de planejamento MRP, porém elas possuem objetivos que podem ser mais facilmente alcançados com o uso de sistemas APS. O aspecto financeiro ainda é limitador para aquisição de sistemas e falta de capacitação. / Due to the great pressure to reduce inventory and delivery, together with the increasing variety of products, production planning and control (PPC) has become increasingly complex and challenging. Basically, this activity aims business planning and control productive resources, to meet customer demand. Traditionally, the literature has addressed the systems MRP, KANBAN, OPT, but a new set of solutions of finite scheduling systems is increasingly being investigated. Companies in search of improvement to the activity of PPC are looking for finite scheduling tools, also known as Advanced Planning and Scheduling (APS) in order to improve the process of order management, including issues such as the determination of time delivery in the stage of negotiation of claims, effective scheduling of orders and production control. This study aims to ascertain the needs and difficulties in the detailed production scheduling, the stage of implementation, and benefits that APS software can provide. The research method was the survey in industries affiliated to the Federation of Industries of Sao Paulo (Fiesp). The results indicated that scheduling production is a complex activity for most companies under the make-to-order strategy (MTO). Companies are using MRPII planning model, but they have goals that can be more easily achieved with the use of advanced planning and scheduling systems (APS). This financial point is still limiting for acquisition of systems and lack of training.

Suivi de notre développement ou encore la compréhension de l’Univers. Deux technologies de capteurs d’image sont actuellement utilisées dans les missions d’imagerie de la Terre et de l’espace : les imageurs CCD (Charge Coupled Device) et CMOS. L’environnement radiatif spatial est constitué de particules énergétiques qui dégradent les performances des imageurs. Et il s’avère que les dégradations réelles observées en vol dépendent fortement des conditions orbitales et de fonctionnement et sont donc très difficiles à prédire. L’étude menée dans le cadre de cette thèse a pour objet la compréhension des dégradations subies par les capteurs CCD et CMOS lorsqu’ils sont soumis à l’environnement radiatif spatial et la proposition de méthodes d’évaluation mieux adaptées pour obtenir une meilleure prédiction de la dégradation réelle d’un imageur en orbite à partir de tests d’irradiation réalisés au sol. La démarche entreprise a tout d’abord consisté à identifier les paramètres d’essais au sol pouvant potentiellement être à l'origine des différences observées entre les résultats sol et vol. Un plan d’essai d’irradiation aux rayons y et aux protons a ainsi été défini afin d’évaluer la dégradation des imageurs CCD et CMOS dans des conditions de fonctionnement et d’irradiation proches de celles en vol. Nous avons étudié l’impact des conditions de mise en opération du composant durant l’irradiation (polarisation, rapport cyclique, etc.) mais aussi l’impact des conditions d’irradiation (débit de dose, énergies des protons, etc.). Le périmètre de cette thèse se limite à l’étude des effets sur le courant d’obscurité, sur la dispersion pixel-à-pixel du courant d’obscurité et sur l’apparition des pixels chauds, qui sont, au premier ordre, les principaux critères de performances dégradés d’un imageur par les radiations. L’étude de l’influence du débit de dose de l’irradiation a montré un phénomène ELDRS (Enhanced Low Dose Rate Sensitivity) pour la première fois sur un capteur CCD polarisé dynamiquement avec un rapport cyclique ON/OFF. Les conditions de polarisation dynamique évaluées sur les APS ont démontré que la dégradation est d’autant plus importante que la fréquence d’activation et le rapport cyclique sont grands. Les irradiations aux protons sur les imageurs CMOS ont aussi montré l’apparition et la guérison de pixels chauds après irradiation à température ambiante ainsi que l'apparition du bruit de signal aléatoire télégraphique (RTS). Ces deux modes de dégradation ont été analysés plus en détail afin d'évaluer leur comportement en guérison pour le premier et extraire les statistiques d'apparition sur l'autre, sur un grand nombre de pixels. En parallèle, un code de simulation de l’effet de dose dans les oxydes de structures élémentaires MOS, ACDC (Accumulation des Charges en Dose Cumulée), a été adapté et utilisé. Ce code a permis de mettre en évidence les constantes de temps impliquées dans la dégradation par effets ionisants dans ces structures. Ces constantes de temps sont utilisées pour l'interprétation des effets de la polarisation dynamique. Les résultats expérimentaux obtenus sur les capteurs d’image CCD et CMOS ont un impact sur l’assurance durcissement. Les irradiations aux protons des imageurs CMOS ont notamment montré un phénomène de guérison des pixels chauds plus marqué que sur les autres pixels, montrant l'intérêt d'une caractérisation de plusieurs semaines après irradiation. Pour les irradiations au Co60 des imageurs CMOS, il est recommandé de ne pas utiliser des temps de polarisation ON trop courts (périodes de cycle petites) car cela peut conduire à une sous-estimation de la dégradation (charge piégée et états d'interface). / Two imaging sensor technologies are presently used in Earth and space imagery missions: Charge Couple Devices (CCD) and CMOS detectors. The space radiation environment is composed of energetic particles that degrade imaging sensor’s performances. It has been shown that real in-orbit degradation of imaging sensors are strongly dependent of orbital and operating conditions and are, as a consequence, difficult to predict. The work performed in this thesis has for purpose an understanding of space radiation-induced degradations for both CCD and CMOS technologies and the proposal of better suited assessment methods for these specific devices in order to better prediction of real in-orbit detector’s degradation from on-ground irradiation tests. The first step of the work focused on the identification of on-ground test parameters that could possibly explain the differences observed between inorbit and on-ground data. Thus an irradiation test plan to y-rays and proton particles has been defined in order to assess the imaging sensor’s degradation for both CCD and CMOS technologies in operating and irradiation conditions close to in-orbit ones. The effects of detector’s operation conditions during irradiation (bias, duty cycle, etc.) but also the irradiation conditions (dose rate, proton energy, etc.) have been studied. The present work focuses on effects on dark current, on its pixel to pixel dispersion and on the presence of hot pixels, which are, at first order, the main performance parameters of an imaging sensor that is degraded by space radiations. The study of the irradiation dose rate influence has shown an Enhanced Low Dose Rate Sensitivity (ELDRS) phenomenon observed for the first time on a CCD imager under dynamic bias condition with a ON/OFF duty cycle. The tested bias conditions CMOS image sensors have demonstrated that the higher the activation frequency and duty cycle, the higher is the degradation. Besides, the proton irradiations performed on CMOS detectors have induced hot pixels that anneal just after irradiation at room temperature. A random telegraphic signal (RTS) behaviour of the dark current has also been shown on CMOS sensors. In parallel to the irradiation tests, a simulation code of ionizing dose effects on oxides of MOS elementary structures has been adapted and used. This program, called ACDC (Accumulation des Charges en Dose Cumulée), has allowed to assess the quantification time constants of physical mechanisms that induce ionizing dose degradation on these structures. These time constants are used for the interpretation of dynamic bias effects.

As altas exigências que impõe o mercado globalizado, a complexidade dos sistemas produtivos de manufatura atuais e os avanços na Tecnologia da Informação são fatos que resgatam a importância da Programação Detalhada da Produção para as empresas. A pesar de bastante consolidada e difundida, a abordagem clássica MRP / ERP não atende plenamente as necessidades em ambientes de produção intermitente. A Programação Detalhada da Produção com capacidade finita dos recursos, atualmente contemplada nos sistemas APS (Advanced Planning & Scheduling), constitui uma alternativa interessante para melhor cumprir prazos de entrega em ambientes com roteiros de produção complexos e produção make-to-order (MTO). O problema de pesquisa ora estudado contempla o ensino de modelos de Planejamento e Controle da Produção (PCP) em um ambiente de produção intermitente, com foco na Programação Detalhada da Produção e nos sistemas MRP e APS. Propõe-se um plano de ensino que busca apresentar e diferenciar essas abordagens. O plano contempla o uso de um caso didático A Fábrica de Skates. De uma forma lúdica, porém realista, o caso apresenta, nas suas cinco etapas, duas situações hipotéticas de uso de sistemas de programação. O primeiro, um MRP para planejamento da fábrica de skates e, no segundo, um APS utilizado pelo fornecedor de eixos. O plano foi aplicado pela primeira vez em uma turma de graduação do curso de Engenharia de Produção. Nesta dissertação, é apresentada uma descrição detalhada do caso didático, junto ao plano de ensino. A pesquisa verificou, mediante análise das atividades do caso e de um questionário de avaliação, a utilidade dos recursos elaborados, como também que as estratégias aplicadas ajudaram na aprendizagem. Nesta primeira aplicação, constatou-se também que a alta carga de trabalho dos alunos no semestre e o pouco peso dado à nota final do caso didático foram fatores que inibiram melhores resultados. Para futuras aplicações, o caso didático pode ser aprimorado: novas etapas contemplando outros assuntos importantes para a disciplina PCP e análise de alternativas para substituição dos softwares empregados são exemplos de melhorias. / The high standard of competition in global market, the complexity of current manufacturing systems and the advances in Information Technology highlight the importance of the detailed production scheduling. Although classical approaches such as MRP perform this function quite well in different situations, these systems do not perform well in make-to-order (MTO) production systems. The finite capacity scheduling currently embedded within the software called APS (Advanced Planning & Scheduling) is a more interesting approach to achieve better performance in meeting due dates in production environments with complex routings and MTO strategy. Thus, the problem addressed in this study concerns the teaching of Production Planning and Control (PPC) models for intermittent production, with focus on the detailed production scheduling using MRP and APS approaches. In order to that, a teaching plan is proposed to present and differentiate these approaches. It includes the use of an educational case study named \"The Skateboard Factory\". In a playful but realistic way, the case presents, in its five stages, two hypothetical situations of use of scheduling systems. First, an MRP approach for planning in the skateboard factory, and second, one APS approach used by the truck supplier. The teaching plan was first applied to an undergraduate degree Production Engineering program. In this dissertation, a detailed description of the educational case study, along with the teaching plan, is provided. The results achieved in the case study and the students evaluation attest to the usefulness of the resources designed, and also that the strategies applied really improved the learning process. In this first application, it was also observed that high workload and the little weight in the final grade of the case study inhibit better results. In future applications, the case can be enhanced to include new stages on other important issues of the PPC discipline and the replacement of the software used.

Devido à grande pressão pela redução de estoques e prazos de entrega, concomitantemente com o aumento da variedade de produtos, o planejamento e controle da produção tem se tornado cada vez mais complexo e desafiador. Basicamente, essa atividade das empresas objetiva planejar e controlar o uso dos recursos produtivos, visando atender à demanda dos clientes. Tradicionalmente, a literatura tem abordado os sistemas MRP, KANBAN, OPT, mas um novo conjunto de soluções de sistemas de programação finita vem sendo crescentemente tratado. As empresas, na busca de aprimoramento para a atividade de PCP estão à procura de ferramentas de programação finita, também conhecidas como Advanced Planning and Scheduling (APS), a fim de melhorar o processo de gerenciamento de pedidos, incluindo quesitos como a determinação de prazos de entrega na etapa de negociação dos pedidos, programação efetiva dos pedidos firmes e controle da produção. Esta dissertação pretende verificar as necessidades e dificuldades da programação detalhada da produção, as barreiras de implantação e os benefícios dos APS. O método utilizado foi o levantamento survey nas empresas filiadas à Federação das Indústrias do Estado de São Paulo (Fiesp). Os resultados obtidos mostram que a programação detalhada da produção é uma atividade complexa para a maioria das empresas com estratégia de produção contra pedido (MTO), que estão direcionadas para aumento de desempenho estratégico. A grande maioria das empresas ainda utiliza o modelo de planejamento MRP, porém elas possuem objetivos que podem ser mais facilmente alcançados com o uso de sistemas APS. O aspecto financeiro ainda é limitador para aquisição de sistemas e falta de capacitação. / Due to the great pressure to reduce inventory and delivery, together with the increasing variety of products, production planning and control (PPC) has become increasingly complex and challenging. Basically, this activity aims business planning and control productive resources, to meet customer demand. Traditionally, the literature has addressed the systems MRP, KANBAN, OPT, but a new set of solutions of finite scheduling systems is increasingly being investigated. Companies in search of improvement to the activity of PPC are looking for finite scheduling tools, also known as Advanced Planning and Scheduling (APS) in order to improve the process of order management, including issues such as the determination of time delivery in the stage of negotiation of claims, effective scheduling of orders and production control. This study aims to ascertain the needs and difficulties in the detailed production scheduling, the stage of implementation, and benefits that APS software can provide. The research method was the survey in industries affiliated to the Federation of Industries of Sao Paulo (Fiesp). The results indicated that scheduling production is a complex activity for most companies under the make-to-order strategy (MTO). Companies are using MRPII planning model, but they have goals that can be more easily achieved with the use of advanced planning and scheduling systems (APS). This financial point is still limiting for acquisition of systems and lack of training.

Das thermische Spritzen ist ein industrieller Beschichtungsprozess, der hauptsächlich zum Schutz oder zur Funktionalisierung von Bauteiloberflächen eingesetzt wird. In der Regel werden mit diesem Verfahren Schichten mit einer Dicke von 50 bis zu einigen 100 Mikrometern aufgetragen, die überwiegend durch mechanische Verklammerung haften, wodurch die Materialeigenschaften des Bauteils weitgehend erhalten bleiben. Mit der Einführung von Suspensionen als neue Kategorie der Spritzzusätze etabliert sich gerade eine der weitreichendsten Innovationen der letzten Jahre auf dem Gebiet des thermischen Spritzens. Suspensionen sind Stoffgemische, die aus einer feindispersen, festen Phase, dem Schichtwerkstoff, und einer flüssigen Phase als Trägermedium bestehen. Damit können Partikel mit geringerer Größe in den Beschichtungsprozess eingebracht werden, so dass sich dünnere Schichten und feinere Mikrostrukturen realisieren lassen. Das thermische Spritzen mit Suspensionen erweitert damit den Anwendungsbereich und bildet eine Brückentechnologie zu den Vakuum- Dünnschichtverfahren. Im Fokus dieser Arbeit stehen die drei wichtigen keramischen Werkstoffe Aluminiumoxid, Chromoxid und yttriumstabilisiertes Zirkonoxid, die in der Form von wasserbasierten Suspensionen als Spritzzusätze für das Atmosphärische Plasmaspritzen (APS) und das Hochgeschwindigkeitsflammspritzen (HVOF) verwendet werden. Für die Injektion der Suspension in das Plasma oder die Flamme wird ein automatisiertes Suspensionsfördersystem verwendet. Darüber hinaus werden spezielle mehrteilige Injektoren entwickelt und getestet. Es werden neue Erkenntnisse zur statistischen Auswertung der Zusammenhänge zwischen den Injektionsparametern, den messbaren Eigenschaften der Tropfenwolke während der Zerstäubung, den Partikeleigenschaften im Spritzstrahl und den daraus resultierenden Schichteigenschaften vorgestellt. Dafür wurde eine neue Kenngröße für den Beschichtungserfolg, ein sogenannter Beschichtungsfaktor, hergeleitet, der sich mit vergleichsweise geringem Aufwand bestimmen lässt und außerdem die zusätzlichen Prozessvariablen beim Suspensionsspritzen mit berücksichtigt. Im Anschluss werden Beispiele für wasserbasierte, suspensionsgespritzte Schichten aus den drei keramischen Werkstoffen vorgestellt, bei denen durch entsprechende Charakterisierungsmethoden das Anwendungspotential im Vergleich zu Spritzschichten nach dem Stand der Technik verdeutlicht wird. Die Anwendungsgebiete umfassen dabei die elektrische Isolation, den Verschleißschutz sowie die thermische Isolation. Den Abschluss der Arbeit bildet eine kritische Diskussion der Eignung von wasserbasierten Suspensionen für das thermische Spritzen mit Plasma- und Flammspritzprozessen. Es werden die Vor- und Nachteile dieser Beschichtungstechnik analysiert und Verbesserungsvorschläge sowohl für die weitere Suspensions- als auch für die Anlagenentwicklung unterbreitet.

O contexto de elevada competitividade empresarial resulta em aumento das exigências por eficiência operacional, como redução dos níveis de estoques e melhoria nos níveis de serviço oferecido aos clientes. Desta forma as decisões tomadas no planejamento tático das companhias ganham complexidade e criticidade. Neste contexto há uma demanda por parte das empresas pela implantação de sistemas de apoio à decisão cada vez mais robustos. É neste cenário que a aplicação de APS no processo de S&OP adquire grande relevância, motivando o entendimento das melhorias trazidas ao processo de planejamento pela ferramenta. Este trabalho foi então norteado por duas questões de pesquisa: quais são os benefícios trazidos para o S&OP com a utilização de APS e quais são os fatores críticos para o sucesso da implantação deste sistema. Para isso, foi feito um estudo de caso em uma empresa que representa bem o contexto desta pesquisa, trata-se de uma grande empresa de lácteos da indústria alimentícia brasileira. Inserida em um setor com elevada competição de mercado e margens de lucro estreitas, há na empresa em questão uma grande necessidade de operar de maneira eficiente. Esta empresa possui múltiplas plantas industriais e passou recentemente pela implantação de um APS para suporte ao seu processo de S&OP, que é responsável pelo planejamento tático integrado da companhia. Como resultado desta pesquisa, identificaram-se os principais benefícios do APS ao processo de S&OP: uma maior confiança e assertividade no processo de planejamento e um melhor balanceamento de estoques em toda cadeia desta empresa. O projeto de implantação passou por algumas dificuldades que atrasaram o cronograma estabelecido, estes pontos merecem ser apontadas como os principais fatores críticos para o sucesso: é importante que o projeto conte com o apoio de toda alta gerência. Quanto à disponibilidade dos dados para desenvolvimento do sistema, é necessário que a empresa tenha processos transacionais integrados para permitir a padronização das informações, além de ser fundamental para o projeto que as pessoas envolvidas na implantação estejam disponíveis para trabalharem com foco no projeto. / Extreme business competition results in increased demands for operational efficiency, such as reducing inventory levels and improving the quality of services offered to customers. Consequently, the decisions in the companies tactical planning gain complexity and criticality. There is a demand by firms for the implementation of increasingly robust decision-support systems. The application of Advanced Planning Systems (APS) in the Sales and Operations Planning (S&OP) process is, then, of utmost importance, motivating the understanding of improvements this tool may add to planning. This dissertation is structured around two research questions: which benefits the use of APS brings to the S&OP, and what are the critical factors for the successful implementation of this system. A case study has been conducted in a company that suits the research: one of the major dairy companies in the Brazilian food industry. Placed in a sector with high market competition and narrow profit margins, one may note the great need the company in question has to operate efficiently. This firm owns several plants and has recently been through the implementation of an APS to support its S&OP process, which is responsible for the integrated tactical planning of the company. The research has identified the main benefits of the APS to the S&OP process: greater confidence and accuracy in planning, and better balancing of inventory throughout the whole firm chain. The deployment project went through specific difficulties that delayed its schedule. Those difficulties should be highlighted as the main critical factors to success, indicating it is important that the project be fully supported by all senior managers. Regarding the availability of data for system development, it is necessary that the company integrate transactional processes, allowing the standardization of information; besides, it is fundamental that the personnel involved in the implementation of the project be available to focus on it.

De nos jours, afin de réduire le frottement et l'usure dans les moteurs thermiques et par voie de conséquence les émissions polluantes ainsi que la consommation énergétique, des revêtements APS (Atmospheric Plasma Spray) sont appliqués sur les chemises des cylindres. Le MoDTC (Di-ThioCarbamate de Molybdène), est un additif organométallique largement utilisé dans la lubrification automobile pour réduire le frottement grâce à la formation sur les surfaces frottantes de feuillets de MoS2. Ce travail de thèse porte sur l’étude de la réaction tribochimique du MoDTC avec le revêtement TiO2 APS dans des conditions de lubrification mixte / limite. Des poudres de TiO2 de taille micrométrique ont été utilisées pour obtenir un revêtement APS de TiO2 de 70 µm d'épaisseur. Différents tribomètres ont été utilisés pour effectuer des essais de frottement en présence d’une huile de base contenant du MoDTC. Les résultats obtenus pour un contact acier / TiO2 APS lubrifié avec du MoDTC présente une réduction significative du frottement par rapport au contact acier / acier (contact de référence). Les analyses de surface montrent que le tribofilm formé sur le plan de TiO2 APS est composé de MoS2 et de MoO3 tandis qu’il est constitué d’oxysulfure de molybdène, de MoS2 et de MoO3 sur le plan de référence en acier. De plus, les résultats indiquent que des phases Magneli résistantes à l'usure sont formées sur la surface du plan de TiO2 réduisant ainsi l'usure du contact lorsque celui-ci est uniquement lubrifié avec l'huile de base. L'impact de divers paramètres tels que la rugosité, la température d'essai, la pression de contact, la concentration en MoDTC et le remplacement des billes en acier par des billes en céramique sur le comportement tribologique du TiO2 APS a également été étudié. Les résultats ont été comparés avec ceux obtenus dans les mêmes conditions avec un contact acier / acier de référence et révèlent que le coefficient de frottement est toujours plus faible dans le cas des contacts impliquant un revêtement de TiO2 APS. Des résultats similaires à ceux obtenus avec le TiO2 APS (en termes de comportement tribologique et de composition chimique du tribofilm) ont été obtenus avec des nanoparticules de TiO2 mélangées dans l’huile de base avec du MoDTC dans le cas d'un contact acier / acier de référence. Dans les deux cas, une décomposition complète de MoDTC conduisant à la formation de MoS2 a été observée. Un phénomène de tribocatalyse a été suggéré comme pouvant être le mécanisme responsable de la décomposition du MoDTC en présence de matériaux à base de TiO2 comme le revêtement TiO2 APS et les nanoparticules de TiO2. / Nowadays to reduce friction and wear as well as gas emission and oil consumption of the passenger car engines, Atmospheric Plasma Spray (APS) coatings are used on cylinder liner. MoDTC (Molybdenum Di-Thiocarbamate), organometallic friction modifier has been previously used to reduce friction by formation of layered molybdenum disulphide flakes. This study focuses on tribochemical interaction of MoDTC with TiO2 APS coating under mixed / boundary lubrication conditions. Fused and crushed micron sized powders were used to obtain a 70 µm thick TiO2 coating. Various tribometers were used to carry out tribotests in presence of lubricant containing MoDTC. Steel / TiO2 APS contact showed significant friction reduction than steel / reference steel contact. It was shown that the tribofilm is composed of MoS2 and MoO3 on TiO2 APS flats while it is composed of Mo-oxysulphide, MoS2 and MoO3 on reference steel flats. It was shown that wear resistant Magneli phases are formed on the surface of TiO2 APS disc, decreasing wear when the contact was lubricated only with base oil. Impact of various parameters like roughness, test temperature, contact pressure, concentration of MoDTC and change of counterpart materials from steel balls to ceramic balls, on the tribological behavior of TiO2 APS was also studied. Results obtained were compared with contacts involving reference steel and it was confirmed that friction coefficient was always lower in case of contacts involving TiO2 APS coating. Similar tribological results and chemistry were obtained for TiO2 nanoparticles blended with MoDTC in case of steel / reference steel contact. Both the cases, TiO2 APS and TiO2 nanoparticles showed complete decomposition of MoDTC to form MoS2. Tribocatalysis was suggested as the mechanism responsible for complete decomposition of MoDTC in case of TiO2 based materials like TiO2 APS coating and TiO2 nanoparticles