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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.
131

Relações e influências da aplicação da acústica no processo de projeto de arquitetura contemporânea / Relations and influences of the application of acoustics in the design process of contemporary architecture

Lopes, Renata Kintschner 07 January 2010 (has links)
Orientador: Stelamaris Rolla Bertoli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-16T06:22:58Z (GMT). No. of bitstreams: 1 Lopes_RenataKintschner_M.pdf: 7318022 bytes, checksum: 02ed66e014e1d1669c84449a051896b5 (MD5) Previous issue date: 2010 / Resumo: No processo de projeto, é necessário que o arquiteto busque soluções integradas para uma série de exigências projetuais. Os fatores acústicos devem ser claramente compreendidos e incorporados no início da conceitualização do projeto arquitetônico, para que a qualidade sonora seja alcançada. O objetivo dessa pesquisa é investigar como os conceitos da acústica arquitetônica interferem na composição arquitetônica durante a fase projetual. Algumas tipologias de edifícios possuem propostas arquitetônicas mais complexas e exigem a participação de muitos especialistas, compondo equipes multidisciplinares. Esses fatores tornam indispensável a aplicação de uma metodologia de projeto, para tornar o processo projetual compreensível e transparente. O método de projeto baseado no desempenho foi identificado como um método adequado para a concepção de edifícios que envolvem vários requisitos de desempenho acústico. A presente pesquisa não pretende impor regras ou diretrizes projetuais, mas busca investigar como o projeto arquitetônico de edifícios pode ser enriquecido a partir do atendimento dos requisitos de conforto acústico e qualidade sonora. A partir da revisão bibliográfica, os aspectos arquitetônicos considerados mais relevantes e abrangentes aos edifícios contemporâneos foram: implantação e meio urbano, forma, dimensões e volume, materiais, mecanismos de variabilidade acústica e metodologia projetual. Para os estudos de caso foram analisadas as seguintes obras: a Sala São Paulo, projetada pelo arquiteto Nelson Dupré e equipe; Casa da Música, do arquiteto Rem Koolhaas; o Centro de Mídia Experimental e Artes Performáticas (EMPAC), do escritório Grimshaw Architects; e a Walt Disney Concert Hall, do arquiteto Frank Gehry. A análise dos resultados obtidos por meio dos estudos de caso foi feita a partir dos mesmos aspectos levantados na revisão bibliográfica, além da análise das metodologias projetuais aplicadas, com o intuito de se fazer uma verificação de como acústica e projeto arquitetônico dialogam em situações reais. Para uma visualização sintetizada, uma tabela foi elaborada relacionando parâmetros acústicos objetivos com os parâmetros subjetivos e as respectivas estratégias arquitetônicas para atendê-los. Espera-se que os requisitos acústicos não sejam somente uma fração da técnica de qualidade sonora, mas também um elemento que enriqueça o partido arquitetônico e a composição da arquitetura contemporânea / Abstract: During the design process, it is necessary for the architect to seek integrated solutions for a number of design requirements. Acoustic factors must be clearly understood and incorporated at the beginning of the design for the sound quality is achieved. The objective of this research is to investigate how the concepts of architectural acoustics affect the architectural composition during the design process. Some types of buildings have architectural proposals more complex and require the participation of many experts, forming multidisciplinary teams. These factors make it essential to apply a design methodology to make the design process understandable and clear. The performance based design method was identified suitable for designing buildings that involve a number of acoustic requirements. This research does not intend to impose rules or design guidelines, but seeks to investigate how the architectural design of buildings can be enhanced by compliance with the requirements of acoustic comfort and sound quality. From the literature review, the architectural aspects deemed most relevant and embracing to contemporary buildings were implantation and urban environment, shape, size and volume, materials, devices of acoustic variability and architectural design methodology. For the case studies the following projects were analyzed: the Sala Sao Paulo, by architect Nelson Dupré and team, Casa da Musica, designed by architect Rem Koolhaas, the Experimental Media and Performing Arts Center (Empac), by Grimshaw Architects, and the Walt Disney Concert Hall, by architect Frank Gehry. The analysis of the results obtained through the case studies was made from the same issues raised in the literature review, and also the analysis of design methods applied in order to make an investigation of how acoustic and architectural design dialogue in real cases. For a synthesized view, a table relates objective acoustic parameters with subjective acoustic parameters and the architectural strategies to meet them. It is expected that the acoustic requirements are not only a fraction of the technique for sound quality, but also an element that enriches the architectural party and the composition of contemporary architecture / Mestrado / Arquitetura e Construção / Mestre em Engenharia Civil
132

Proposta de metodologia baseada em projeto axiomático para tomada de decisões em projeto de dispositivos / Proposal of a methodology based on axiomatic design for decision making regarding the design of devices

Pacifico, Douglas Sozzi 17 August 2018 (has links)
Orientador: João Maurício Rosário / Dissertação (mestrado profissional) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-17T09:31:47Z (GMT). No. of bitstreams: 1 Pacifico_DouglasSozzi_M.pdf: 4000960 bytes, checksum: 072558107a877761c6e2de97a3ee0100 (MD5) Previous issue date: 2010 / Resumo: Os projetos de engenharia são até hoje amplamente baseados em processos empíricos, em metodologias ad hoc e em métodos iterativos. A experiência de quem os executa tem grande influência nos resultados obtidos por conta da falta de critérios científicos para a análise e tomada de decisões ao longo do desenvolvimento de um produto ou de um processo. As conseqüências mais comuns são os problemas de qualidade e confiabilidade, os atrasos na execução e a extrapolação dos custos previstos. Atualmente existem poucas metodologias científicas com abordagem global de um projeto, dentre elas podemos considerar o Projeto Axiomático. Desenvolvida ao longo das últimas décadas pelo Prof. Nam Pyo Suh, ela propõe dois axiomas básicos para nortear a análise e tomada de decisões em projetos de qualquer ordem, os quais são então desdobrados em teoremas e corolários específicos. Embora não possa ser demonstrada ou comprovada enquanto axioma, a metodologia tem sido constantemente validada por sua utilização bem-sucedida em diferentes especialidades técnicas, da manufatura ao desenvolvimento de produtos, da organização de empresas à tecnologia da informação. Apesar da clareza de sua proposição e da existência de modelos matemáticos para seu uso, o Projeto Axiomático não é de simples e direta aplicação às diferentes especialidades técnicas a que se propõe. Esta dissertação de mestrado tem como proposta desenvolver uma metodologia pragmática e acessível para a aplicação integral do Projeto Axiomático à tomada de decisões em projetos de dispositivos de manufatura. A metodologia desenvolvida é então validada e demonstrada através da aplicação da mesma em um caso fabril real de uma indústria de autopeças de grande porte / Abstract: Engineering design is till present times widely based on empiric processes, ad hoc methodologies and iterative methods. The experience of those who perform the task is of great influence on the outcome due to the lack of scientific criteria for both analysis and decision making along the development of a product or a process. The common consequences are quality and reliability problems, execution delays and cost overrun. Currently there are only a few scientific design methodologies with a holistic approach, Axiomatic Design among them. Developed during the last decades by Prof. Nam Pyo Suh, it proposes two basic axioms to guide the analysis and decision-making for projects of any kind, both being then unfolded in theorems and corollaries. Although not able of being neither demonstrated nor proved as axiom, the methodology has been constantly validated through its successful utilization on different technical fields, from manufacturing to product design, from organizational structures to information technology. In spite of the clearness of its proposition and the existence of mathematical models for its usage, the Axiomatic Design is not of simple and direct application to the different technical fields it is suitable for. This master's degree dissertation has the purpose of developing a pragmatic and accessible methodology for the complete application of the Axiomatic Design to the decision making regarding the design of devices. The proposed methodology is then validated and demonstrated through its application to a real industrial process in a large size multinational automotive industry / Mestrado / Projetos / Mestre em Engenharia Automobilistica
133

Modelo de suporte ao projeto criativo em arquitetura: uma aplicação da triz - teoria da solução inventiva de problemas. / Supportive model for the creative design in architecture: an application of TRIZ - theory of inventive problem solving.

Marly Kiatake 02 July 2004 (has links)
A mudança nas relações funcionais entre os agentes da indústria da construção civil, a velocidade dos avanços tecnológicos e a intensa competitividade entre os escritórios de arquitetura evidenciam uma necessidade crescente de organização do processo de projeto, cujo aprimoramento pode ser alcançado através do uso de metodologias sistemáticas. Entretanto, a ininteligibilidade e a falta de domínio do processo criativo do arquiteto resultam, muitas vezes, em sistemas metodológicos ineficazes, devido à deficiência de ferramentas que suportem a criatividade do projetista, na fase de concepção das idéias. A Teoria da Solução Inventiva de Problemas (TRIZ) é uma metodologia que direciona o processo criativo, através da proposição de Princípios Inventivos (PIs) e identificação de padrões na evolução dos sistemas. Conceituando a contradição como um elemento chave para a criação, é baseada em pesquisas de patentes mundiais de vários campos do conhecimento. Estudos preliminares, identificando diversos princípios da TRIZ em soluções arquitetônicas existentes, incentivaram-nos à exploração da metodologia na área da arquitetura, objetivo deste trabalho. Na tentativa de uma primeira validação do modelo, realizou-se um estudo de caso no Conjunto Residencial da USP (CRUSP), no qual a teoria foi utilizada para solucionar o problema de adequação da acessibilidade dos edifícios às pessoas portadoras de deficiência física. O estudo de caso demonstrou que a TRIZ é uma alternativa metodológica para a fase inicial do processo de projeto arquitetônico, à medida em que possui ferramentas para sistematizar o conhecimento do problema, delimitar o espaço de busca por soluções e sinalizar as idéias potencialmente relevantes. / The modification in the functional relationships among the project players of the building construction industry, the speed of technological advances and the strong competitiveness among the architectural offices are indications of a growing need for organization of the design process, whose improvement has been achieved through systematic methodologies. However, the unintelligibility and lack of management of the architect's creative process result, a lot of times, in ineffective methodological systems, caused by a deficiency of tools that support the designer's creativity in the phase of conceptual design. The Theory of Inventive Problem Solving (TRIZ) is a methodology that improves the creative process through the propositions of Inventive Principles (IPs) and identification of some patterns in the evolution of the systems. The theory considers the contradiction as the key element for innovation and it is based on researches about worldwide patents of several fields of knowledge. Preliminary studies identified several TRIZ Principles in existent architectural solutions and motivated us to the exploration of the methodology in this field, which was the goal of this work. In the attempt of a first validation of the model, a case study was accomplished in the Residential Building of Universidade de São Paulo (CRUSP), using TRIZ to solve the problem of adaptation of the buildings for accessibility by disabled people. The case study demonstrated that TRIZ is a methodological alternative for the early phases of architectural design process, because it includes tools to systematize the problem knowledge, to delimit the search space for solutions and to signal the ideas potentially relevant.
134

Desenvolvimento e fabricação de uma mini-impressora 3D para cerâmicas / Development and manufacturing of mini 3D printer machine for ceramics

Luis Hilário Tobler Garcia 14 January 2011 (has links)
O trabalho trata do estudo do processo de impressão tridimensional e desenvolvimento de uma impressora para a produção de corpos-de-prova cerâmicos. A técnica de impressão tridimensional pertence ao grupo de prototipagem rápida e consiste na obtenção de um corpo sólido a partir de um modelo digital de três dimensões, através do fatiamento do modelo tridimensional e da impressão seqüencial de suas respectivas fatias. Durante o processo de impressão, deposita-se um ligante sobre camadas sucessivas de pó e em cada camada, o ligante consolida o pó no formato bidimensional da fatia, que por fim soma-se as outras fatias subseqüentes, consolidando assim o formato tridimensional do modelo. Os equipamentos convencionais de impressão 3D utilizam pós a base de gesso e acrílico, onde o ligante, a base de água, fornece a primeira adesão química; posteriormente é infiltrada uma resina para fornecer uma ligação com o pó de acrílico. Na impressão de cerâmica a base de alumina ou zircônia, o desenvolvimento de ligantes tem de ser realizado visando à adesão química e orgânica combinadas antes da sinterização. Neste projeto, uma mini impressora 3D para corpos de prova foi desenvolvida e com ela foram produzidos corpos de geometria simples e seção constante, cujo projeto, custo, manutenção simplificada e econômica possibilita também o emprego de materiais agressivos nos ligantes, com risco de danificação de componentes, a exemplo de ácido fosfórico, porém com baixo custo de recuperação. Foram analisados diversos tipos pelo dimensionamento de seus aglomerados, fluidez e densidade. Obteve-se pó a base de gesso por R$15,00 o kilograma. Corpos de prova foram analisados com relação à resistência mecânica por flexão de três pontos, densidade, porosidade aparente e imagens por microscopia ótica e microscopia eletrônica de varredura (MEV). Um protótipo de uma mini-impressora foi idealizado, projetado e fabricado, soluções originais e econômicas foram propostas e na sua validação alguns conceitos necessitam de melhorias, ainda assim foram obtidos resultados promissores. Foi desenvolvida uma formulação de pó baseado em gesso que teve o custo de aproximadamente 5% do produto importado. / The work studies the three-dimensional printing process and the development of a 3D printer to produce ceramic specimen. The 3D printing technique belongs to the rapid prototype group and consists in obtaining a solid body from a three-dimensions digital model, through the slicing of the three-dimensional model and the sequential printing of their respective slices. During the printing process, a binder is deposited upon successive powder layers, and in each layer, the binder consolidates the powder into the bi-dimensional shape of the slice, which ultimately adds to the other slices that followed, consolidating the three-dimensional shape model. The conventional 3D printing equipments uses powder based in gypsum and acrylic, where the water-based binder, provides the first chemical bind; subsequently is infiltrated a resin to provide a binding with the acrylic powder. In the ceramic printing based on alumina or zirconia, the development of binders must be accomplished looking for a organic and chemical bind before sintering. In this project, a mini 3D printer for ceramic specimens was developed and built, with it were be produced bodies of simple geometry and constant section, which design, cost and simplified maintenance and cost also enable the use of aggressive materials in binders, with the risk of components damage, such as phosphoric acid, but with low cost to recovery. Were analyzed several types of powders by the sizing of its clusters, fluidity and density. Were obtained gypsum powder for $ 7.00 a kilogram. The specimen were analyzed in relation to the mechanical strength by three-point bending, density, apparent porosity and images by optical microscopy and scanning electron microscopy (SEM). A prototype of a mini 3D printer was designed, engineered and manufactured, unique and economical solutions have been proposed and in its validation some concepts need of improvement, yet promising results were obtained. It was developed a powder formulation based on gypsum that has cost about 5% of the imported product.
135

Estimativa de desempenho de uma NoC a partir de seu modelo em SYSTEMC-TLM. / A NoC performance evaluation from a SYSTEMC - TLM model.

Martha Johanna Sepúlveda Flórez 16 October 2006 (has links)
The wide variety of interconnection structures presently nowadays for SoC (Systemon- Chip), bus and networks-on-Chip NoCs, each of them with a wide set of setup parameters, provides a huge amount of design alternatives. Although the interconnection structure is a key SoC component, there are few design tools in order to set the appropriate configuration parameters for a given application. An efficient SoC project may comply an exploration stage among the possible solutions for the communication structure, during the first steps of the design process. The absence of appropriate tools for that exploration makes critical the designer?s judgment. The present study aims to enhance the communication SoC structure design area, when a NoC is used. This work proposes a methodology that allows the establishment of the NoC communication parameters using a high level model (SystemC TLM timed). Our approach analyzes and evaluates the NoC performance under a wide variety of traffic conditions. The experimental stage was conducted employing a model of a net represented by a SystemC TLM timed (Hermes_Temp). Parametric and pseudo-random generators control the network traffic. The analysis was carried on with a tool designed for these purpose, which generates a group of performance metrics. The results allow to elucidate the global and inner network behavior. The performance values are useful for the heterogeneous and homogeneous NoC design projects, improving the performance evaluation studies scope. / The wide variety of interconnection structures presently nowadays for SoC (Systemon- Chip), bus and networks-on-Chip NoCs, each of them with a wide set of setup parameters, provides a huge amount of design alternatives. Although the interconnection structure is a key SoC component, there are few design tools in order to set the appropriate configuration parameters for a given application. An efficient SoC project may comply an exploration stage among the possible solutions for the communication structure, during the first steps of the design process. The absence of appropriate tools for that exploration makes critical the designer?s judgment. The present study aims to enhance the communication SoC structure design area, when a NoC is used. This work proposes a methodology that allows the establishment of the NoC communication parameters using a high level model (SystemC TLM timed). Our approach analyzes and evaluates the NoC performance under a wide variety of traffic conditions. The experimental stage was conducted employing a model of a net represented by a SystemC TLM timed (Hermes_Temp). Parametric and pseudo-random generators control the network traffic. The analysis was carried on with a tool designed for these purpose, which generates a group of performance metrics. The results allow to elucidate the global and inner network behavior. The performance values are useful for the heterogeneous and homogeneous NoC design projects, improving the performance evaluation studies scope.
136

Processus et méthodes pour la résolution de problèmes interdisciplinaires et pour l'intégration de technologies dans des Domaines fortement Basés sur la Connaissance / Processes and Methods for Interdisciplinary Problem Solving and Technology Integration in Knowledge-intensive Domains

Schofer, Malte 10 April 2015 (has links)
Les principaux enjeux technico-scientifiques du 21ème siècle sont caractérisés par une interdisciplinarité et une convergence des technologies de plus en plus importantes. L'évolution des produits et services basés sur la bio- et la nanotechnologie sont parmi les exemples les plus connus. Il manque cependant des processus et des méthodes permettant d'organiser et de structurer la résolution de problème dans des environnements interdisciplinaires – ce terme faisant ici référence à la collaboration entre ingénieurs et chercheurs scientifiques.Ainsi, la question de recherche de ce travail de doctorat est la suivante :Comment soutenir et faciliter la résolution créative de problème interdisciplinaire et l'intégration des technologies dans des domaines basés sur la connaissance ?Pour répondre à cette question, trois hypothèses ont été formulées :La première hypothèse suggère que la composition d'un groupe en terme de disciplines (groupe multi- ou monodisciplinaire) a un impact sur le processus de résolution de problème en groupe ainsi que sur les résultats de ce processus.La deuxième hypothèse suggère un impact du support méthodologique sur le processus de résolution de problème en groupe ainsi que sur les résultats de ce processus.La troisième hypothèse suggère quant à elle que les concepts et notions clés des méthodes analytiques comme TRIZ et USIT peuvent être utilisés dans un processus d'intégration de technologie et peuvent soutenir ce processus.Les deux premières hypothèses ont été testées et validées par une expérimentation dans laquelle des groupes mono- et multidisciplinaires devaient générer des solutions pour un problème complexe en utilisant des méthodes intuitives ou analytiques. Alors que la composition de groupe impacte principalement les aspects quantitatifs et qualitatifs des solutions proposées, le support méthodologique influence quant à lui le processus de résolution de problème ainsi que les aspects qualitatifs des solutions. Plus important, l'impact des méthodes semble être dépendant de la composition des groupes.Pour tester la troisième hypothèse, les résultats de la première expérimentation ont été utilisés pour générer un modèle permettant de structurer la recherche et l'intégration d'une ou plusieurs technologies dans le cadre du développement de nouveaux produits. Ce modèle, qui intègre des méthodes et outils provenant de différentes méthodologies, a été testé par des ingénieurs lors d'une étude de cas industrielle dans le secteur des roulements à bille. L'évaluation du modèle montre qu'il semble faciliter le transfert de connaissance et améliorer la créativité des concepts développés comparé aux approches déjà existantes. En ce qui concerne l'effort nécessaire pour l'apprentissage et la mise en œuvre du modèle développé, les performances sont comparables à celles obtenues avec les méthodes préexistantes.Les résultats de ce travail sont particulièrement intéressants pour les équipes de la R et D et leur management dans les secteurs de la haute technologie ainsi que dans des domaines à l'interface entre l'ingénierie et les sciences naturelles. Le modèle développé est actuellement appliqué dans une démarche d'open innovation dans le secteur de la pharmacologie. / Most of the major technological challenges of the 21st century like e.g., reduction of greenhouse gas emission and sustainable energy supply, but also the bio- and nano-technological revolutions require intensified collaboration between different disciplines of engineering design as well as of natural science.The present Ph.D. research tries to provide some insight into the questions of• How to provide methodological support for creative problem solving in interdisciplinary groups composed of engineers and natural scientists?• How to support the process of the integration of a technology originating from a knowledge-intensive domain in order to solve a given design problem?The literature analyzed relevant aspects on several systemic levels (global, institutional, team-, individual and problem- perspective).The review allowed highlighting problems related to both, the activity as such as well as to the methods which seem a priori appropriate to support it. In this regard, incoherent interpretive schemes and majority influence are examples for the former and performance drawbacks as well as learning difficulties associated to hierarchical methodologies are instances of the latter.Based on the results of the literature review, two experiments were conducted.The first experiment inquired into the impact of disciplinary group composition (H1) as well as of the applied methodology (H2) on the creative group problem solving process and its outcomes.In a laboratory experiment 60 participants, 45 with a life science background and 15 with a mechanical engineering background were trained either in instances of intuitive approaches (Brainstorming, Mind Mapping) or in analytical, hierarchical methodology (TRIZ/USIT). Then, they had to solve an ill-defined medical problem in either mono- or multidisciplinary teams. The creative process as well as the output was documented using questionnaires and documentation sheets. Further the output was evaluated quantitatively by two domain experts before it was categorized qualitatively.Statistical analyses (ANOVA, Correlation parameters and Attraction rates), to a certain extent, support H1 and H2. More importantly however, the experiment shows differences related to method performance in general and as a function of disciplinary group composition in particular.The second experiment investigated whether concepts of TRIZ and its derivatives ((A/U)SIT) are appropriate to provide support for the process of technology integration before the background of an industrial NCD/NPPD process (H3).In order to test this hypothesis a model was developed which allows the identification and resolution of problems which typically appear during the integration of a specific technology into a given application. The model incorporates two of the most important concepts of TRIZ, and is sought to facilitate creative problem solving attempts in both, mono- and multidisciplinary teams.The said model was tested during an industrial NCD study in the roller bearing industry. After the case study, the participating engineers were asked to compare the applied model and the associated technology integration process with existing approaches used in the company.The results of the experiment point to superior performance of the presented model in terms of knowledge transfer-related and idea quality-related criteria. However, required resources for process conduction and necessary effort for the learning of the approach were considered comparable to existing approaches.The present Ph.D. work contributes to the understanding of creative problem solving in interdisciplinary groups in general and related to technology integration in particular. Especially the comparison of more pragmatic intuitive methods with more hierarchical analytical approaches depending on disciplinary group composition provided relevant insight for R&D processes.
137

Optimal Tundish design methodology in a continuous casting process

De Kock, Daniel Johannes 07 October 2005 (has links)
The demand for higher quality steel and higher production rates in the production of steel slabs is ever increasing. These slabs are produced using a continuous casting process. The molten steel flow patterns inside the components of the caster play an important role in the quality of these products. A simple yet effective design method that yields optimum designs is required to design the systems influencing the flow patterns in the caster. The tundish is one of these systems. Traditionally, experimental methods were used in the design of these tundishes, making use of plant trials or water modelling. These methods are both costly and time consuming. More recently, Computational Fluid Dynamics (CFD) has established itself as a viable alternative to reduce the number of experimentation required, resulting in a reduction in the time scales and cost of the design process. Furthermore, CFD provides more insight into the flow process that is not available through experimentation only. The CFD process is usually based on a trial-and-error basis and relies heavily on the insight and experience of the designer to improve designs. Even an experienced designer will only be able to improve the design and does not necessarily guarantee optimum results. In this thesis, a more efficient design methodology is proposed. This methodology involves the combination of a mathematical optimiser with CFD to automate the design process. The methodology is tested on a four different industrial test cases. The first case involves the optimisation of a simple dam-weir configuration of a single strand caster. The position of the dam and weir relative to inlet region is optimised to reduce the dead volume and increase the inclusion removal. The second case involves the optimisation of a pouring box and baffle of a two-strand caster. In this case, the pouring box and baffle geometry is optimised to maximise the minimum residence time at operating level and a typical transition level. The third case deals with the geometry optimisation of an impact pad to reduce the surface turbulence that should result in a reduction in the particle entrainment from the slag layer. The last case continues from the third case where a dam position and height is optimised in conjunction with the optimised impact pad to maximise the inclusion removal on the slag layer. The cases studies show that a mathematical optimiser combined with CFD is a superior alternative compared to traditional design methods, in that it yields optimum designs for a tundish in a continuous casting system. / Thesis (PhD (Mechanical Engineering))--University of Pretoria, 2006. / Mechanical and Aeronautical Engineering / unrestricted
138

Estudo do trançado para desenvolvimento de produtos têxteis artesanais / Study of artisanal braiding for the development of handmade textiles products

Duarte, Adriana Yumi Sato, 1988- 22 August 2018 (has links)
Orientador: Franco Giuseppe Dedini / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-22T03:41:34Z (GMT). No. of bitstreams: 1 Duarte_AdrianaYumiSato_M.pdf: 12125505 bytes, checksum: 3905d87344e274e166ea8b7f129f87c3 (MD5) Previous issue date: 2013 / Resumo: A presente pesquisa tem como objetivo propor uma linguagem para a técnica artesanal de trançado manual, atividade praticada em diversas regiões do Brasil que utiliza materiais flexíveis para desenvolver produtos como cestos e esteiras, de modo a sistematizar a construção das armações e reafirmar a importância desta atividade para o país nos aspectos sociais, culturais e econômicos. Para tanto, o cenário desta pesquisa é baseado na análise da produção artesanal no Brasil, estudo do trançado manual e suas atividades análogas e a inserção das diretrizes de metodologia e ferramentas de projeto neste contexto. O conhecimento atrelado à prática do trançado manual é transmitido de forma oral e geracional, e em razão disto, está sendo perdido progressivamente. Por este motivo, como consequência da sistematização do trançado, o resgate deste conhecimento também é contemplado na pesquisa. Os resultados da pesquisa indicaram a relação entre o trançado manual e a tecelagem, atividade têxtil que transforma fios em tecidos, transferindo a nomenclatura, representação numérica e gráfica da tecelagem para o trançado manual. Assim, o que se pretende nesta pesquisa é sugerir uma linguagem para o trançado manual, ainda inexistente na área, que permita o desenvolvimento de um banco de dados e, futuramente, novas armações / Abstract: This research aims to propose a language for the artisanal braiding, a handicraft technique practiced in different regions of Brazil that uses flexible materials to develop products like baskets and mats, in order to systematize the construction and to reaffirm the importance of this activity in social, cultural and economic aspects. Therefore, the background of this research is based on the analysis of handicraft production in Brazil, the study of the braiding and its similar activities and the insertion of guidelines from methodology and design tools in this context. The knowledge linked to this practice is transmitted orally and between generations, and because of this, is being gradually lost. For this reason, as a consequence of the systematization of braiding, the rescue of this knowledge is also covered in this survey. The results indicated the relationship between artisanal braiding and weaving, a textile activity that transforms yarn into fabric, transferring the numerical and graphical representation for weaving to braiding. So, what is intended in this research is to suggest a language for artisanal braiding, which is lacking in the area, in order to allow the development of a database and, in future, new patterns / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestra em Engenharia Mecânica
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Contribution au Dimensionnement Optimal d'Alternateur à Griffes Sans Aimant - Apport des alliages FeCo / Contribution to Optimal Sizing of Claw-Pole Alternator Without Magnet - Contribution of FeCo alloys

Perez, Sylvain 25 November 2013 (has links)
L'alternateur à griffes est l'alternateur le plus utilisé dans l'industrie automobile. Afin d'augmenter sa puissance volumique, une solution classique consiste à utiliser des aimants NdFeB entre les griffes. Ces dernières années, le prix des aimants NdFeB a beaucoup augmenté remettant en question leur utilisation. Ce contexte implique de trouver de nouvelles solutions techniques permettant de conserver la même puissance volumique sans utiliser d'aimant NdFeB. Dans le cadre de ces travaux de thèse la solution proposée consiste a utiliser des matériaux magnétiques doux nobles tels que les FeCo (AFK18, AFK1 et AFK502). De part leur coût élevé, nous avons limité leur utilisation au noyau de l'alternateur même si leur utilisation au rotor est également évaluée. Ces travaux s'appuient sur une démarche de dimensionnement multi-niveaux (modèle reluctant et modèle éléments finis) ce qui apporte un bon compromis temps de calcul/précision. Une série d'études a été réalisée avec dans un premier temps, l'identification d'une géométrie de noyau favorable à l'utilisation de noyau en FeCo. Dans un second temps, une étude compare les courants batteries en fonction du FeCo utilisé au noyau avec une optimisation du rotor. Ensuite une étude présente le dimensionnement complet de l'alternateur (optimisation du rotor et du stator avec une étude sur le nombre optimal de paires de pôles) avec un noyau en AFK502 ce qui d'identifier le gain maximal en courant batterie apporté par l'utilisation d'un noyau en FeCo. Pour finir, une dernière étude compare les courants batteries en fonction du FeCo utilisé au rotor avec une optimisation du rotor et du stator. / Claw-pole alternators are often used in automotive industry. Permanent magnets like NdFEB are currently integrated to increased the power density of claw-pole machine. However their higher price brings into question their usage. This tight context implies finding new technical solutions to keep the same power density without NdFeB magnets. The solution adopted consists to evaluate the potential of gain with different soft magnetic materials and more especially FeCo family (AFK18, AFK1 et AFK502). Their higher price imposed us to use FeCo just at the core of the alternator but we have also evaluate their usage at the rotor. This work is based on an adapted design methodology including two modeling level (magnetic equivalent circuit model and finite element model) in order to obtain a good compromise between time computation/accuracy. Several studies have been made with, as a first step, the identification of new core geometry customized for FeCo core. As a second step, a study comparing output current according to FeCo used at the core is presented, rotor is optimized only. As a third step, is exposed the global optimization of the alternator with an AFK502 (rotor and stator optimization with a study on the optimal poles pairs number) in order to identify the maximum output current gain with an FeCo core. Finally, the last study compare output current according to FeCo used at the rotor, rotor and stator are optimized .
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Algoritmos evolutivos como método para desenvolvimento de projetos de arquitetura / Evolutionary algorithms as a method for developing architecture design

Martino, Jarryer Andrade de, 1976- 27 August 2018 (has links)
Orientador: Maria Gabriela Caffarena Celani / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-27T01:58:13Z (GMT). No. of bitstreams: 1 Martino_JarryerAndradede_D.pdf: 15987793 bytes, checksum: e3e7fece0c549d866ab2fb31f75bd0c8 (MD5) Previous issue date: 2015 / Resumo: O projeto de arquitetura é composto por diferentes variáveis que precisam ser constantemente negociadas, algumas delas envolvem situações contraditórias, aumentando a complexidade da solução do problema. Os algoritmos evolutivos correspondem a um conjunto de técnicas que contribuem para a solução desse tipo de problema, e que podem ser incorporados ao sistema generativo de projeto de maneira a potencializar a obtenção de melhores resultados. Para isso, foi necessário entender a teoria evolucionista e os seus principais mecanismos, a estruturação e a implementação dos algoritmos evolutivos no ambiente computacional, e a sistematização do processo de projeto como base para o desenvolvimento de um método evolutivo. Dessa forma, foi definido um quadro teórico composto pelos principais eventos e conceitos relacionados à teoria evolucionista, à computação evolutiva e à discussão na década de 1960 sobre a sistematização do processo de projeto como uma sequência operativa capaz de registrar o processo mental do projetista, e o método evolutivo de projeto de arquitetura, sendo apresentada a sua estrutura, os componentes e exemplos. Embora esse método tivesse sido implementado na arquitetura na década de 1960, foi verificado que as aplicações estavam bastante restritas, limitando-se a trabalhos acadêmicos em universidades específicas. O domínio de uma linguagem de programação e a falta de clareza e apropriação dos vocabulários, conceitos e técnicas desenvolvidas pela Computação Evolutiva dificultaram a sua implementação como método de projeto na arquitetura e urbanismo. Atualmente, existem recursos digitais que facilitam a implementação desse método de maneira simplificada sem perder a eficiência do método, justificando a sua retomada como um método de projeto pelos arquitetos e urbanistas. Dessa forma, os objetivos desta pesquisa foram os de organizar o conteúdo teórico dos algoritmos evolutivos de maneira a esclarecer a sua estrutura, o vocabulário, os conceitos básicos e os mecanismos que os envolvem, de definir como ocorre a sua relação com o elemento arquitetônico e com o método de projeto, da identificação de uma ferramenta computacional capaz de facilitar a sua implementação e o de apresentar situações concretas em que os arquitetos e urbanistas possam utilizá-los. Como resultado foi possível verificar que não existe dificuldade no entendimento do mecanismo evolutivo como possível recurso para o desenvolvimento de um método de projeto, mas sim, a necessidade de maior domínio sobre a ferramenta de programação que não estaria relacionada diretamente com o sistema evolutivo, mas sim, com a descrição algorítmica através de um código computacional de todo processo de projeto / Abstract: The architecture design is composed by different variables that need to be negotiated, some of them involve contradictory situations, increasing the complexity of the solution. The evolutionary algorithms are set by techniques that contribute to obtain solutions for this kind of problems, and they also may be incorporated in a project generative system in a way that potentiate the best results obtaining. For this it was necessary to understand the evolutionary theory and its main mechanisms, the structuring and implementation of evolutionary algorithms in computational environment, and the systematization of the design process as a base of an evolutionary design method development. Thus, it was important to define a theoretical framework from the main events and concepts related to the evolutionary theory, the evolutionary computation and to the discussion in the 1960s about the systematization of the design process as an operative sequence capable of registering the mental process of the designer and the evolutionary design method on architecture with their components and examples. Although this method had been implemented in architecture in the 1960s, its application was quite restricted to academic works development in some specific universities. The necessity of the knowledge of programming language, vocabulary, concepts and techniques from evolutionary computation made the implementation difficult as a project method in architecture and urbanism. Currently, there are digital resources that facilitate the method simplified implementation without losing its efficiency, justifying its resumption as a design method by architects and urban planners. Moreover, the objectives of this research were to organize the content about evolutionary algorithms, clarifying its structure, vocabulary, basic concepts and the involved mechanisms, to define its relationship with the architectural element and the project method, to identify a computational tool that facilitates the implementation and to present the real situations which architects can use them. As a result it was possible to validate that there is no difficulty in understanding the evolutionary algorithm as possible resource for the methodology development of a design, yet, the necessity to have more experience in the utilization of programming tool. This tool is not directly related to the evolutionary system, but with the algorithmic description through the computational implementation by any project codes / Doutorado / Arquitetura, Tecnologia e Cidade / Doutor em Arquitetura, Tecnologia e Cidade

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