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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Interneto vartotojo sąsajos projektavimo metodika ir jos taikymas interneto paslaugų teikėjo sistemai / Methodology of Web Interface Design and its Application for Internet Service Provider System

Martišius, Gytis 25 August 2010 (has links)
Kuriant sistemą, kuri turės sąsają internete, reikia turėti metodiką, kuria būtų galima vadovautis projektuojant šią sąsają. Objektinio projektavimo metoduose ir unifikuotame kūrimo procese RUP (angl. Rational Unified Process) nėra aprašytų specialių procesų interneto sąsajai kurti. Nors šia tema rašė nemažai autorių, tačiau sunku rasti vientisą metodiką, kuria galėtų vadovautis interneto sąsajos ir ja paremtos sistemos kūrėjas. Šiame darbe tiriami esami interneto sistemų sąsajos projektavimo metodai, šablonai bei įvairios kūrimo technologijos, siekiant juos sukonkretizuoti, apibendrinti ir sukurti metodinę medžiagą, kurią būtų galima taikyti interneto sistemas projektuojančioje organizacijoje, mokymo procese ar pateikti kaip gidą, bet kuriam interneto sąsajos projektuotojui. Šiais laikais kompiuteriai dalyvauja daugelyje sričių, ir bendravimas tarp žmogaus ir kompiuterio neišvengiamas. Kad vartotojas galėtų valdyti sistemą, šis bendravimas vyktų sklandžiai, reikalinga sąsaja. Esamos sistemos turi sąsają, tačiau susistemintos metodikos, kaip reikėtų kurti tą sąsają, nėra daug, ji išsklaidyta atskiruose literatūros šaltiniuose ar interneto puslapiuose. Dažnai ši metodika slypi projektuotojų mintyse, bet ji taip ir lieka neaprašyta ir pats sąsajos projektavimas būna intuityvus. / Nowadays, information system creation process consists of several different actions, one of those actions – web interface design. Web interface design process requires a good methodology, to make web interface process better, quicker, flexible and satisfy other web interface design criterions. RUP (Rational Unified Process) don’t present any special creation process of internet web interface. Frequently web interface design process lies in the head of it’s designers. There are no full methodology of web interface design process in one place, only some web interface advices or articles about one or other web interface process steps could be found. The goal of this work is to make a methodology of web interface design and implement it for internet service provider system. Methodology also would be useful for companies which participate in web interface design process, also in school or university study process, or like a guide for any web interface designer. The developed methodology for web interface design was used for implementing internet service provider system web interface, system design process and redesign above-mentioned system web interface for measuring process times. Methodology of web interface design, reduce web interface design process time, help to make web interface design process easier, more flexible and understandable for web interface designer, also certain better web interface appearance independence from system functional part, with possibility to... [to full text]
142

Designmetodik för hållbara förpackningslösningar : Med fokus på ekologiskt perspektiv och reducerat matsvinn / Design methodology for sustainable packaging solutions

Olsson, Frida January 2016 (has links)
Denna rapport återger det arbete som syftat till att ta fram hjälpmedel för att utveckla hållbara förpackningslösningar. Projektet har genomförts som ett examensarbete för högskoleingenjörs- programmet i innovationsteknik och design vid fakulteten för hälsa, natur- och teknikvetenskap på Karlstads universitet. Arbetet har realiserats med stöd från Helén Williams, forskare inom energi- och miljöteknik. I dagsläget saknas metoder och hjälpmedel för att utveckla hållbara livsmedelsförpackningar där matsvinn tas in som en aspekt. Därför har en serie med tre verktyg utvecklats, från befintlig designprocessmetodik för tillämpning vid produktutveckling av hållbara förpackningslösningar, med fokus på reducerat matsvinn och minskad miljöpåverkan. För att få underlag till utvecklingen av verktygen har en förstudie genomförts där designprocess, hållbar utveckling, förpackning och matsvinn studerats. Förstudien har följts av en analys för att kartlägga var i produktutvecklingsprocessen verktyg för hållbar utveckling saknas. Detta för att identifiera faser med behov av fler hjälpmedel och resurser. Vidare har de olika faserna studerats mer ingående och det har lett fram till det slutliga resultatet bestående av verktygsmallar och riktlinjer för funktionsanalys, kvalitetshus och Pugh’s metod för reducerat matsvinn. För att sätta den centrala delen, kvalitetshusmallen, i ett verklighetsperspektiv har ett test utförts. Objektet för testet är tre olika varianter av mjölkförpackningar. Verktygen är ämnade till förpackningsdesigners och förpackningsteknologer för att underlätta deras arbete och vägval mot mer hållbara lösningar genom ett minskat produktsvinn. Att verktygen är enkla och användarvänliga är ett mål och en förutsättning för att de ska komma till användning. / This report covers a process that has aimed to contribute with tools for development of sustainable packaging solutions. The project has been implemented as a Bachelor thesis for the programme in  innovation and design engineering at the faculty of health, science and technology at Karlstad university. The project has been carried out with support from Helén Williams, researcher of  environmental and energy systems. Today there is a lack of methods and tools for developing sustainable packaging solutions, in which food waste is taken in as an aspect. A set of three tools has therefore been elaborated from existing methods. The set can be applied in the designprocess of sustainable packaging solutions to achieve reduced food waste and environmental impact. The feasibility study of the project has aimed to provide information for support and included the keywords: design process, sustainable development, packaging and food waste. After the feasibility study, an analysis has been made. The intention has been to map where tools for sustainable development are missing. This would help to identify the phases of the design process with extra need of methods and tools. The analysis has given an opportunity to study the selected phases more thoroughly. That has led to the final result consisting of templates and guidelines for function analysis, QFD and Pugh’s method for reduced food waste. A test has been performed to put the central part, the QFD-template, into a reality perspective. The objects for the test consists of three types of milk packages. The tools are aimed to be used by package designers and packages technologists to facilitate their work and decisions to more sustainable solutions through reduced product waste. The goal and the prerequisite are that the tools should be easy and user friendly. If not there is a risk that they might not be used.
143

Contribution à l’amélioration du processus d’industrialisation du laminage transversal / A contribution to the industrialization of the cross wedge rolling process

Gutierrez, Catalina 26 September 2017 (has links)
Le laminage transversal est un procédé de mise en forme où un lopin cylindrique est déformé plastiquement en une pièce axisymétrique comportant des réductions de diamètre. Dans le processus de fabrication de bielles, le procédé est utilisé pour l’opération de répartition avant les opérations d’estampage. Par rapport au procédé de laminage à retour, il permet d’atteindre de meilleures mises au mille et de réduire les temps de cycle. L’industrialisation de ce procédé se heurte toutefois à des difficultés liées pour l’essentiel à la conception des outillages.Ces travaux de thèse visent à améliorer le processus d’industrialisation du laminage transversal par une réduction des temps de développement des outillages et par l’allongement de leur durée de vie. Pour cela, deux axes ont été identifiés. D’une part l’amélioration et la formalisation de la méthodologie de conception des outillages et d’autre part, l’identification et la caractérisation des phénomènes défauts se produisant à grand nombre de cycle et provocant l’arrêt de l’outillage.Ces travaux de thèse s’orientent au tour de trois axes majeurs. Premièrement, l’évaluation du potentiel prédictif de la simulation numérique du laminage transversal et sa robustesse vis-à-vis des paramètres numériques et du procédé. Deuxièmement, la mise en place d’un processus de conception d’outillage comportant d’un côté une méthodologie de conception permettant de définir les paramètres de l’outillage en s’appuyant d’un autre côté sur la simulation numérique du procédé. Troisièmement, l’identification et la caractérisation des zones d’usure et ses effets sur la pièce laminée / Cross wedge rolling (CWR) is a metal forming process used in the automotive industry. One of its applications is in the manufacturing process of connecting rods. CWR transforms a cylindrical billet into a complex axisymmetrical shape with an accurate distribution of material. This preform is forged into shape in a forging die. CWR industrialization has still some limitations, mainly the designing of the tools. This thesis work seeks to improve CWR industrialization by reducing the time needed for the design of the tools and by increasing CWR tool lifecycle. In order to achieve these goals, two main axes are identified: improving the tool design procedure and identifying the physical phenomenon affecting the stability of the process, mainly tool wear.This research work is based upon three main topics. First, evaluating of the predictability of the numerical simulation of the CWR process and its robustness towards the numerical parameters of the model and the process parameters. Second, implementing a design methodology that allows the designer to choose the geometrical parameters of the wedge and evaluating the resultant geometry of the tool through the numerical simulations. And third, identifying the wear zones of the tool and the factors leading to its development
144

Os espaços experimentais das escolas públicas de arquitetura do Brasil: realidade ou utopia? / The experimental workspaces in public schools of architecture in Brazil: reality or utopia?

Laverde, Albenise 23 June 2017 (has links)
Esta tese está inserida no debate sobre a utilização da experimentação construtiva ao longo da concepção da materialidade e seu papel como recurso pedagógico. Trata mais especificamente, dos espaços e práticas experimentais no contexto acadêmico nacional, objetivando compreender o processo de configuração dos espaços da área técnico-construtiva implantados nas escolas públicas de arquitetura de acordo com as particularidades advindas de diferentes contextos do país, das políticas educacionais e das ações dos atores envolvidos, com a identificação das condições essenciais para que estas práticas sejam implantadas e potencializadas no contexto acadêmico. O trabalho foi desenvolvido a partir de pesquisas documentais e por meio de visitas técnicas realizadas em 21 escolas públicas de arquitetura localizadas em diferentes regiões do país, com entrevistas direcionadas aos principais atores que atualmente estão à frente da área da Tecnologia da Construção. O trabalho trouxe contribuições de ordem teórica a partir da sistematização de uma bibliografia abrangente sobre um tema pouco estudado no contexto nacional. Quanto às contribuições de ordem prática, os dados obtidos nas visitas técnicas possibilitaram contextualizar os desafios enfrentados no ensino da Tecnologia da Construção, que não se resumem ao arranjo físico laboratorial, mas a uma dimensão mais ampla, abrangendo aspectos político-educacionais, estruturais e sócio-econômicos e também, questões de fundo, como as relações interpessoais e burocráticas. Estes resultados permitiram identificar as condições consideradas como essenciais na (re)formulação de estratégias voltadas à área da Tecnologia da Construção e sua infraestrutura, de maneira que as experiências existentes possam ser potencializadas e novas implantações tenham maior respaldo técnico de acordo com as particularidades contextuais. / This thesis is inserted in the debate about the use of experimentation in building along with the conception of materiality and its role as pedagogical resource. It approaches, more specifically, the experimental workspaces and practices in the Brazilian academic context. It aims to understand the process of shaping the workspaces of the technology and construction fields established in public schools of architecture according to the singularities from different contexts of the country, educational policies and activities of the actors involved, identifying the essential conditions for those practices to be implemented and strengthened in the academic context. The work was developed based on documentary research and through technical visits in 21 public schools of architecture located in different regions of the country, with interviews directed to the main actors who are currently in charge of the field of Technology of Construction. In relation to the practical contributions, the data obtained in the technical visits made it possible to contextualize the challenges faced in the education of Technology of Construction. These challenges are not limited to the physical arrangement of the laboratory; they embrace a broader dimension, covering education politics, structural and socioeconomic aspects and, still, background issues such as interpersonal relations and bureaucracy. These results enabled the identification of conditions considered essential in the (re) formulation of strategies directed to the field of Technology of Construction and its infrastructure, so that the existing experiences can be strengthened and new applications can have a greater technical support according to the contextual singularities.
145

Methodological approach for the sustainable design of structured chemical products during early design stages / Approche méthodologique pour la conception durable de produits chimiques structurés dans les premières phases de la conception

Serna Rodas, Juliana 13 December 2018 (has links)
En raison de la compétitivité dans le marché des produits chimiques et la demande croissante pour les produits de qualité, l'industrie et l'académie sont à la recherche de nouvelles méthodes pour la conception des produits chimiques. Par conséquent, cette étude propose une approche méthodologique pour faciliter la prise de décisions dans la conception de produits de type émulsion. Les caractéristiques de la méthodologie proposée sont les suivantes: elle propose des méthodes pour l’analyse des besoins de consommateurs, la génération d'idées pour la conception du produit et la sélection du meilleur produit, en prenant en compte la nature multi-variée du problème de conception avec l'intégration de la notion de durabilité dans le processus de conception. La méthodologie comporte trois étapes de conception: Étape de besoins, étape de génération d'idées et étape de sélection d'idées. Dans la première étape, les besoins sont analysés et classifiés en fonction de leur impact sur la satisfaction du client. Ensuite, ils sont traduits aux spécifications du produit avec l’aide des experts et des clients. Les informations de saisie correspondent aux besoins des clients et celles de sortie correspondent aux spécifications du produit, c'est-à-dire des caractéristiques du produit qui peuvent être évaluées. Également, deux méthodes sont utilisées: le modèle de kano et la méthode QFD (Déploiement des Fonctions Qualités). Dans la seconde étape, les produits répondant aux spécifications sont conçus en suivant une démarche en trois phases: 1) le problème de conception est divisé selon un groupe défini de sous-problèmes généraux. 2) Chaque sous-problème est connecté à un groupe de stratégies de solution selon une première matrice de décision prédéfinie. 3) Les stratégies de solution sont connectées avec des ingrédients et des conditions opératoires selon une deuxième matrice de décision. Cette démarche est faite en utilisant deux matrices de décision développées dans cette recherche sur la base de la connaissance de science d'émulsion, ainsi que sur des connaissances des experts. Dans la troisième étape, les alternatives de produit sont évaluées selon le cahier de spécifications définis dans la première étape et les indicateurs de durabilité appropriés. Ces indicateurs sont utilisés pour évaluer et classer les alternatives de produit selon un indice de développement durable global. Pour développer cette étape un ensemble d'indicateurs évaluant la dimension économique, environnementale et sociale de produits est choisi et ils sont intégrés par la mise en oeuvre d’une méthode d'analyse de multi-critère. Finalement, afin d’illustrer la méthodologie, une étude de cas est développée: la conception d'une crème hydratante / Emulsion based chemical products, which belong to the category of micro-structured chemical products, have a broad range of commercial applications. Despite their importance, there is not a general methodology for their design. With the aim to contribute to the progress on this matter, this research presents a product design methodology focused on emulsion design with the following characteristics: it proposes methods for customer needs analysis, product ideas generation and selection of the best product alternative. It considers the multivariate nature of emulsion design by taking into account the multiple effects of design variables into product properties. It integrates sustainability concepts into the product design process. The methodology comprises three design stages: needs stage, ideas generation stage and ideas selection stage. In the needs stage, customer needs are first analyzed and classified according to their effect on customer satisfaction and second translated into product specifications with the aid of experts and customers. The input is customer needs, i.e., statements expressing customers’ desires about the product, and the output corresponds to product specifications, i.e., product characteristics that can be measured. To perform this stage two methods are used: Kano model and Quality Functional Deployment. In ideas generation stage, product concepts accomplishing product specifications are generated in three sub-steps: First, problem specifications are classified into a predefined group of design sub-problems. Second, each sub-problem is connected with one or more pre-defined solution strategies through a prefilled relational matrix. Third, compatible solution strategies are selected and connected to ingredients and processing conditions through a second relational matrix. As result, a set of product concepts is generated. Thisprocedure is developed by the implementation of two relational matrices proposed in this research based on emulsion science and expert knowledge. The first connects sub-problems with solution strategies and the second connects solution strategies with ingredients and processing conditions. In the selection stage, generated product concepts are evaluated according to product specifications. In addition, appropriated sustainability indicators are included to assess and rank product alternatives according to a global sustainability index. To perform this stage, a set of indicators are selected and integrated by the implementation of multi-criteria analysis methods. The application of the methodology is exposed with a case study: the design of a moisturizing cream
146

Metodologia de desenvolvimento baseado em modelos e sua aplicação em máquinas agrícolas

Costa, Felipe Tozetto 30 June 2017 (has links)
Submitted by Angela Maria de Oliveira (amolivei@uepg.br) on 2017-11-30T10:37:02Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Felipe Costa.pdf: 2622002 bytes, checksum: ae1227fbb019301002367ceabaa6dd1e (MD5) / Made available in DSpace on 2017-11-30T10:37:02Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Felipe Costa.pdf: 2622002 bytes, checksum: ae1227fbb019301002367ceabaa6dd1e (MD5) Previous issue date: 2017-06-30 / O presente trabalho tem por objetivo apresentar a aplicação da metodologia baseado em modelos (MBD – model-based design) para o desenvolvimento de dispositivos eletrônicos de controle e automação para máquinas agrícolas. Baseado nos conceitos de MBD, foi proposto o desenvolvimento de uma central eletrônica embarcada para controle de funções específicas de uma plantadeira. Baseado na definição de requisitos, utilizou-se um conjunto dos principais sensores e atuadores para o desenvolvimento do modelo. Utilizou-se ferramentas como Matlab/Simulink® para o modelamento em fluxo de estados e geração de código automático o qual foi validado em software através da etapa MIL (Model-in-the-Loop). Posteriormente, realizou-se a geração automática de código através da etapa SIL (Softwarein- the Loop), validando-se o firmware gerado em software; e, através da etapa PIL (Processor-in-the Loop), validou-se experimentalmente o código gerado gravando-o no microcontrolador e utilizando materiais de apoio para simulação experimentalmente dos sensores e atuadores. Posteriormente, uma vez validadas as partes do projeto e, como forma de avaliação do sistema em uma situação próxima da realidade de um plantio, desenvolveu-se uma aplicação para avaliar com dispensa controlada de sementes, inclusive avaliando uma possível obstrução de um dos orifícios do disco de dispensa. Como resultado, esta aplicação teve por objetivo propor uma ferramenta para avaliar a distância média do plantio entre sementes, velocidade média do plantio e gerar informações estatísticas a respeito da precisão da dispensa de sementes. Por fim, os resultados de validação e experimentais são apresentados, os quais permitiram concluir que a metodologia baseada em modelos pode ser aplicada também em sistemas agrícolas resultando no rápido desenvolvimento de dispositivos de eletrônica embarcada e permitindo os processos de teste e validação durante o seu desenvolvimento. / The present work presents the application of the model-based methodology (MBD) for the development of electronic control and automation devices for agricultural machines. Based on the concepts of MBD, it was proposed the development of an embedded electronic central to control the specific functions of a planter. Once the requirements were defined, we used a set of the main sensors and actuators for the development of the model. We used tools such as Matlab/Simulink® for stateflow modeling and automatic code generation which was tested and validated in software through MIL (Model-in-the-Loop) step. Later, the automatic generation of code was performed through the Software-in-the-Loop (SIL) step, validating the firmware generated in software; and, through the Processor-in-the-Loop (PIL) step, the generated code was validated by recording it in the microcontroller and using support materials for experimental simulation of sensors and actuators. Later, once the parts of the project were validated and, as a way of evaluating the system in a situation close to the reality of a planting, an application was developed to evaluate with a controlled dispense of seeds, including evaluating a possible obstruction of one of the holes in the dispensing disc. As a result, the objective of this application was to propose a tool to evaluate the average planting distance between seeds, average planting velocity and to generate statistical information about the accuracy of the seed dispensation. Finally, the validation and experimental results are presented, which allowed to conclude that the model-based methodology can be applied also in agricultural systems resulting in the rapid development of embedded electronics devices and allowing the processes of testing and validation during its development.
147

Design Methodology for High-performance Circuits Based on Automatic Optimization Methods. / Mise en place d'une démarche de conception pour circuits hautes performances basée sur des méthodes d'optimisation automatique

Tugui, Catalin Adrian 14 January 2013 (has links)
Ce travail de thèse porte sur le développement d’une méthodologie efficace pour la conception analogique, des algorithmes et des outils correspondants qui peuvent être utilisés dans la conception dynamique de fonctions linéaires à temps continu. L’objectif principal est d’assurer que les performances pour un système complet peuvent être rapidement investiguées, mais avec une précision comparable aux évaluations au niveau transistor.Une première direction de recherche a impliqué le développement de la méthodologie de conception basée sur le processus d'optimisation automatique de cellules au niveau transistor et la synthèse de macro-modèles analogiques de haut niveau dans certains environnements comme Mathworks - Simulink, VHDL-AMS ou Verilog-A. Le processus d'extraction des macro-modèles se base sur un ensemble complet d'analyses (DC, AC, transitoire, paramétrique, Balance Harmonique) qui sont effectuées sur les schémas analogiques conçues à partir d’une technologie spécifique. Ensuite, l'extraction et le calcul d'une multitude de facteurs de mérite assure que les modèles comprennent les caractéristiques de bas niveau et peuvent être directement régénéré au cours de l'optimisation.L'algorithme d'optimisation utilise une méthode bayésienne, où l'espace d’évaluation est créé à partir d'un modèle de substitution (krigeage dans ce cas), et la sélection est effectuée en utilisant le critère d’amélioration (Expected Improvement - EI) sujet à des contraintes. Un outil de conception a été développé (SIMECT), qui a été intégré comme une boîte à outils Matlab, employant les algorithmes d’extraction des macro-modèles et d'optimisation automatique. / The aim of this thesis is to establish an efficient analog design methodology, the algorithms and the corresponding design tools which can be employed in the dynamic conception of linear continuous-time (CT) functions. The purpose is to assure that the performance figures for a complete system can be rapidly investigated, but with comparable accuracy to the transistor-level evaluations. A first research direction implied the development of the novel design methodology based on the automatic optimization process of transistor-level cells using a modified Bayesian Kriging approach and the synthesis of robust high-level analog behavioral models in environments like Mathworks – Simulink, VHDL-AMS or Verilog-A.The macro-model extraction process involves a complete set of analyses (DC, AC, transient, parametric, Harmonic Balance) which are performed on the analog schematics implemented on a specific technology process. Then, the extraction and calculus of a multitude of figures of merit assures that the models include the low-level characteristics and can be directly regenerated during the optimization process.The optimization algorithm uses a Bayesian method, where the evaluation space is created by the means of a Kriging surrogate model, and the selection is effectuated by using the expected improvement (EI) criterion subject to constraints.A conception tool was developed (SIMECT), which was integrated as a Matlab toolbox, including all the macro-models extraction and automatic optimization techniques.
148

Metodologia de especificação e projeto aplicado a usinas nucleares móveis / Specification and design methodology applied to mobile nuclear power plants

Freire, Luciano Ondir 08 October 2018 (has links)
A importância de métodos de projeto vem crescendo nos últimos anos à medida que sistemas sócio-técnicos complexos se tornam mais numerosos. Além da complexidade, o tamanho e o investimento financeiro destes sistemas amplificam a gravidade dos erros de projeto. O objetivo geral deste trabalho foi desenvolver uma metodologia de especificação e projeto que reduza o tempo e energia para desenvolver um sistema complexo cujas funções sejam conhecidas a priori, gerenciando em paralelo os riscos. O objetivo específico foi verificar a viabilidade econômica de usinas nucleares móveis de pequeno porte. Este trabalho adotou como princípio a lei construtal que prevê o sucesso de sistemas que facilitem os fluxos necessários à sua existência. Após a identificação dos fatores chave para facilitar o fluxo de informações, esta tese desenvolveu um conjunto de conceitos para facilitar o trabalho de engenharia. Aplicando tais conceitos, este trabalho desenvolveu sequências de atividades que descrevem o método proposto, sendo cada atividade detalhada por uma lista de requisitos. A demonstração das vantagens do método proposto foi feita por meio de análise de árvore de eventos e árvore de falhas. Usando o método, esta tese desenvolveu especificações e projetos em vários níveis (empresarial, usina, caldeira nuclear, circuito primário e gerador de vapor). Baseando-se em dados da marinha americana, esta tese desenvolveu um modelo de custo para reatores de pequeno porte. Concluiu que a energia nuclear pode ser competitiva se a potência elétrica média efetiva ao longo da vida útil ficar acima de 30MWe e se o tempo de vida útil for igual ou maior do que 60 anos. Tal fato decorre dos altos custos de aquisição que requerem uma vida longa para compensar o investimento e dos efeitos de economia de escala especialmente pronunciados para reatores a água pressurizada. / The importance of design methodologies has been growing in recent years as complex socio-technical systems become more common. In addition to complexity, the size and financial investment of these systems amplifies the severity of design errors. The general goal of this work was to develop a specification and design methodology that reduces the time and energy to develop a complex system whose functions are known a priori, managing the risks in parallel. The specific goal was to verify if small modular reactors could be economically possible. This work adopted as principle the Constructal law, that predicts the success of systems that ease the necessary flows to its existence. After finding the key factors to ease the flow of information, this work developed a set of concepts to ease the engineering work. Applying such concepts, this work developed sequences of activities that describe the proposed methodology. Lists of requirements gave guidance for each activity. Event tree and fault tree analyses showed the advantages of the proposed methodology. Using the methodology, this work developed specifications and designs at many product breakdown levels (enterprise, nuclear power plant, nuclear steam supply system, reactor coolant system and steam generator). Using data from US Navy, this work developed a cost model for small reactors. This work concluded that nuclear power may be competitive if average electrical power extracted during the life is larger than 30 MWe and if life time is superior to 60 years. The first condition is consequence of the high overnight costs of nuclear power. The second is consequence of the strong scale economy effects of pressurized water reactors.
149

Fully FPGA-based Sensorless Control for synchronous AC drive using an Extended Kalman Filter / Fully FPGA-based Sensorless Control for synchronous AC drive using an Extended Kalman Filter

Idkhajine, Lahoucine 24 November 2010 (has links)
L'objectif du travail réalisé dans le cadre de cette thèse est de montrer l'intérêt d'utiliser les FPGAs (Field Programmable Gate Array) comme support pour l'implantation d'algorithmes complexes dédiés à la commande de machines électriques. Pour ce faire, une commande sans capteur mécanique utilisant un filtre de Kalman étendu et basée sur FPGA est réalisée. Cette commande est destinée à piloter une machine synchrone à pôles saillants. Le modèle d-q de la machine basé sur l'approximation d'inertie infinie est implanté. L'ordre du Filtre de Kalman est donc égal à 4 et la complexité totale de la boucle de régulation est évaluée à près de 700 opérations arithmétiques (dont plus de 53% de multiplications). Les apports des solutions FPGAs en termes de performances de contrôle et en termes de capacité d'intégration sont quantifiés.En terme de performances de contrôle, il a été démontré qu'en utilisant de telles solutions matérielles, le temps de calcul est très réduit (de l'ordre de 5µs, 5% de la période d'échantillonnage). Cette rapidité de calcul permet d'avoir un contrôle quasi-instantané ce qui améliore la bande passante de la boucle de régulation. A ce sujet, une comparaison avec les performances obtenues avec une solution logicielle telle que le DSP est effectuée. Dans les deux cas, le comportement dynamique de la boucle de régulation s de vitesse ans capteur est quantifié.En termes de capacité d'intégration, il est possible de développer une architecture commune qui peut être adaptée à plusieurs systèmes. A titre d'exemple, il est possible de développer un filtre de Kalman sur un même FPGA capable d'estimer les grandeurs de plusieurs systèmes sans pour autant affecter les performances de contrôle. En outre, une méthodologie de développement dédiée à de tels algorithmes complexes est proposée. Il s'agit là d'une adaptation des méthodologies proposées dans des travaux de thèse précédents, [62] et [63]. En effet, une étape de spécification préliminaire du système ainsi que des procédures d'optimisation supplémentaires y sont introduites. Ces dernières sont particulièrement nécessaires dans le cas de commandes complexes et permettent une adéquation entre l'algorithme développé et l'architecture FPGA correspondante. De plus, cette méthodologie a été organisée de façon à distinguer l'étape du développement de l'algorithme et l'étape du développement de l'architecture FPGA. Un état de l'art sur les technologies FPGA est également proposé. La structure interne des FPGAs récents est décrite. Leur contribution dans le domaine de la commande des machines électriques est quantifiée. Les différentes étapes de la méthodologie de développement sont présentées. Le développement d'une commande numérique (basée sur FPGA) d'une machine synchrone à aimant permanent associée à un capteur de position Resolver est par la suite traité. Cette application s'inscrit dans un contexte avionique où l'objectif était d'avoir une solution FPGA hautement intégrée. Pour ce faire, le FPGA Actel Fusion est utilisé. Ce composant intègre un convertisseur analogique numérique. La commande, le traitement des signaux Resolver ainsi que la conversion analogique numériques sont implantés sur le même composant.En ce qui concerne la commande sans capteur basée sur le filtre de Kalman étendu, il a été décidé de structurer les chapitres correspondants à travers la méthodologie de développement proposée. Ainsi, la phase de spécification préliminaire du système, la phase du développement de l'algorithme, la phase du développement de l'architecture FPGA et la phase d'expérimentation sont séparément traitées. Durant la phase d'expérimentation, la procédure «Hardware-In-the-Loop (HIL)» est incluse afin de valider le fonctionnement de l'architecture développée une fois la phase d'implantation physique achevée. / The aim of this thesis is to present the interest of using Field Programmable Gate Array (FPGA) devices for the implementation of complex AC drive controllers. The case of a sensorless speed controller using the Extended Kalman Filter (EKF) has been chosen and applied to a Salient Synchronous Machine (SSM). The d-q model based on the infinite inertia hypothesis has been implemented. The corresponding EKF order is then equal to 4 and the complexity of the whole sensorless controller is equal to 700 arithmetic operations (more than 53% of multiplications). The contribution of FPGAs in this field has been quantified in terms of control performances and in terms of system integration. In terms of control performances, the proposed FPGA-based solution ensures a short execution time which is around 5µs (5% of the sampling period). This treatment fastness ensures a quasi-instantaneous control which improves the control bandwidth. To this purpose, a comparison with a software DSP-based solution is made. The dynamic behavior and the influence of the execution time, in both cases, on the control bandwidth have been quantified. In terms of integration capacity, it is possible to implement a generic FPGA architecture that can be adapted to the control of several systems. Thus, it is possible to develop a common EKF architecture that is able to estimate variables from many systems without affecting the control performances.In addition, a design methodology adapted to such complex controllers has been proposed. The particularity of this updated methodology, compared to the previous ones ([62], [63]), is to provide an enlarged set of steps starting from the preliminary system specification to the ultimate experimentation. Optimization procedures have also been introduced. These optimizations are necessary in case of complex controllers and lead to the adequation between the developed algorithm and the corresponding hardware FPGA architecture. A state of the art FPGA technology is also presented. The internal structure of the recent devices and their corresponding technology are discussed. Their contribution in the field of AC drive applications is quantified. An in-depth presentation of the proposed design methodology is made.Besides, the development of a fully integrated FPGA-based controller for a Permanent Magnet Synchronous Machine (PMSM) associated with a Resolver sensor is presented. This controller has been developed in for an aircraft application where the main objective was to develop a fully integrated FPGA solution. The Actel Fusion FPGA device has been used. This device integrates an Analog to Digital Converter (ADC). The current controller, the Resolver Processing Unit (RPU) and the analog to digital conversion are implemented within the same device. When it comes to the sensorless controller, the corresponding chapters have been structured according to the presented design methodology: the preliminary system specification, the algorithm development, the FPGA architecture development and finally the experimentation. The latter includes Hardware-In-the-Loop (HIL) tests and the final experimental validation.
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Metodologia para projeto, construção e ensaios em máquina síncrona de imã permanente - MSIP / Methodology for design, construction and testing on permanent magnet synchronous machine - PMSM

Fernando Henrique Pisani Teixeira 18 August 2006 (has links)
A grande aplicação residencial de motores de indução monofásicos é em sistemas de refrigeração doméstica/comercial. O desenvolvimento de motores mais eficientes, associado ao controle de velocidade, fez com que, dentro os mais diversos tipos de motores, o motor síncrono de imã permanente tornasse objeto para a criação de uma metodologia de projeto, construção e realização de ensaios. Assim, para adequar o projeto do motor MSIP para substituição do motor de indução monofásico, foram feitos estudos de como aproveitar as laminações já existentes, através de definições das características básicas do estator e do rotor. O imã permanente a ser utilizado foi definido principalmente em função do custo do material e de suas propriedades magnéticas estarem adequadas à necessidade do projeto. O projeto magnético foi feito para maximizar o fluxo nos dentes, considerando as características construtivas e a curva de trabalho dos imãs. O projeto elétrico, a partir de um circuito equivalente do motor, permitiu explicar as relações de torque, corrente e tensão do motor MSIP, bem como a definição das bobinas do motor, quanto ao espaçamento destas entre as ranhuras, o cálculo do número de espiras e o diâmetro dos fios em função da área permitida pela ranhura da lamina do estator. Com as informações obtidas após o cálculo do motor MSIP, passou-se a construção de um protótipo constituído pelo estator, rotor e um sistema de suporte que permitisse o levantamento dos parâmetros do motor. Os parâmetros necessários foram definidos levando-se em consideração a necessidade para o projetista do conversor elétrico, sendo estes dados utilizados em simulações computacionais para a determinação do projeto do acionador. Com isto, os ensaios do motor MSIP permitiram o levantamento dos seguintes parâmetros: resistência, indutância, curvas de tensão de fase e linha da eletromotriz por velocidade em diversas rotações, momento de inércia e atrito viscoso, concluindo assim a proposta deste trabalho, e finalizando a metodologia para o motor MSIP. / A major residential application of single-phase induction motors is in domestic refrigeration. The development of more efficient motors, associated with speed control, has made that, among the most diverse types of electrical motors, the permanent magnet synchronous machine becomes an object of study for a design, construction and testing methodology. Therefore, to suit the PMSM design to replace the single phase induction motor, studies were made on how to take advantage of existing laminations, through definitions of the basic characteristics of the stator and rotor. The permanent magnet used was defined mainly as a function of the cost of the material and its magnetic properties since they suit the design requirements. PMSM magnetic design was made to maximize the magnetic flow in the slots considering the constructive characteristics and the magnet curve. The electric design, starting from a motor equivalent circuit, allowed to explain torque, current and voltage of the PMSM motor, as well as the definition of the motor windings regarding their filling in the slots, the calculation of coil number and the wire diameter as a function of the area allowed by the stator lamination slot. With the information obtained after the PMSM motor calculation, a prototype construction was initiated consisting of the stator, rotor and a support system to allow determining the motor parameters. The required parameters were defined taking into account the need the designer had of an electronic drive had. This data was used in computational simulations to determine the electronic driver design. After this, the motor testing allowed to identify the parameters, namely: winding resistance and inductance, various speed curves versus phase to phase and line voltage for back emf´s, moment of inertia and viscous friction, thus completing this work proposal, finalizing the project methodology for PMSM motor.

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