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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.
11

Modelo para redução de custos na cadeia de suprimento do aço estampado : o caso Renault-Nissan no Brasil / Model for reduction of osts in the supply chain of the stamped steel : the case Renaut-Nissan in Brazil

Anthonijsz, Maggie Marianne 19 December 2007 (has links)
Made available in DSpace on 2016-12-12T20:32:02Z (GMT). No. of bitstreams: 1 DISSERTAcao Maggie Marianne Anthonijsz.pdf: 885760 bytes, checksum: 2bb05216019fcb414a3968cf9d43ed86 (MD5) Previous issue date: 2007-12-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Não foi permitido cópia, apenas leitura / Não permite cópia, somente leitura
12

Sportovní hala / Sports Hall

Kačírek, Michal January 2018 (has links)
The aim of the final thesis is to design steel structure of the sports hall in Brno. The design is processed in two options. The option "A" is designed in variant of flat space frame with dimensions 78x46,5 m and the structure height is 13,0 m. The option "B" is designed in variant of truss girder with parabolic lower belt and purlin. Dimensions are 84x46,5 m and the structure height is 12,8 m. Roof covering and curtain walling is made of sendwich panels with polyurethane foam and trapezoidal sheet.
13

Estudo da influência do meio corrosivo na resistência à fadiga do aço estrutural SAE 8620

Nelson do Nascimento Atanazio Filho 26 May 2006 (has links)
Nenhuma / A corrosão-fadiga é provavelmente um dos mais complexos de todos os fenômenos, sendo influenciada por fatores ambientais, mecânicos, metalúrgicos, somados a uma componente cíclica de tensões. A corrosão-fadiga pode ser definida como a ação combinada de um ambiente agressivo e uma tensão cíclica que conduzem à falha prematura dos metais por trincamento. A maior parte da vida em fadiga está relacionada a uma sucessão de processos durante os quais planos de escorregamento, deformações localizadas, danos e micro trincas se iniciam e desenvolvem até a nucleação de trinca macroscópica. Neste estudo, a influência da solução de NaCl 3,5% nas propriedades de fadiga do aço foi avaliada. Foram analisadas as curvas de S-N-P obtidas sob ambiente corrosivo e comparadas com as curvas de S-N-P obtidas em água destilada. Em geral, a corrosão-fadiga em soluções aquosas é um processo eletroquímico. O mecanismo de iniciação de trincas por corrosão-fadiga proposto para explicar a redução da vida em fadiga de metais em ambientes corrosivos, foi analisado neste trabalho
14

Influência das ligações no dimensionamento das estruturas tubulares circulares de aço treliçadas / Joint influence on design of steel circular hollow section truss structure

Sepúlveda, Bárbara Daniela Giorgini, 1986- 23 August 2018 (has links)
Orientador: João Alberto Venegas Requena / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-23T22:44:13Z (GMT). No. of bitstreams: 1 Sepulveda_BarbaraDanielaGiorgini_M.pdf: 5435418 bytes, checksum: 5d55af89b27e919b7c819e297b4cf056 (MD5) Previous issue date: 2013 / Resumo: Este artigo apresenta o estudo da influência das ligações no comportamento das estruturas treliçadas compostas por perfis tubulares de aço. As ligações em treliças de aço são normalmente projetadas para união de barras por meio de chapas que garantam a transmissão e equilíbrio das forças. No caso em particular de treliças que utilizam perfis tubulares de aço as ligações são projetadas sem chapas. As barras são unidas diretamente por meio de soldas nos contatos dos perfis que são cortados geometricamente exatos para o ajuste da ligação. Este procedimento aumenta a produtividade de fabricação além de dar um aspecto visual melhor para a estrutura. Dependendo da geometria da ligação podem ocorrer excentricidades dos eixos provocando a introdução de momentos fletores, que quando não puderem ser evitados, devem ser levados em consideração não só no cálculo da ligação como também na determinação dos esforços da treliça. Outro aspecto importante é a análise do colapso da ligação que pode ocorrer quando uma barra é associada à outra de forma inadequada na ligação direta, sendo variados os tipos de falhas. Portanto, será analisada a influência das ligações no comportamento da estrutura a partir de gráficos baseado no estudo das equações de força resistente das ligações tubulares circulares. Este estudo gráfico permitiu a criação do processo de cálculo, denominado Processo Simplificado, que orientam para as combinações de perfis que atendam as exigências geométricas e de força resistente das ligações durante o dimensionamento de barras. O processo é baseado em de tabelas de cálculo desenvolvidas para a orientação de um bom projeto de estrutura treliçada considerando ou evitando estas influências sem onerar o projeto final / Abstract: This paper presents the study of connections influence in the behavior of hollow sections truss structures. Joints in steel trusses are usually designed considering sheets that will ensure the transmission and balance of forces. In particular case of trusses using hollow sections steel connections are designed without plates. The beams are directly welded to steel sections which are geometrically cut to fit the joint. This increases manufacturing productivity in addition to give the structure a better visual appearance. Axes eccentricities can occur depending on connection geometry resulting in introduction of bending moments. When this eccentricity cannot be avoided, it has to be taken into account in joint design and also in determining truss efforts. Another important aspect is analysis joint collapse which can occur when a beam is improperly associated to another beam, which can produce many kinds of fails. Therefore, graphics analyses were studied based on circular hollow sections joint strength equations that show the influence of joints on structures. The Simplified Process, created after graphics studies, shows the valid combinations of circular hollow sections geometry and strength during beam structure design verification. This process is based on tables developed to orient a good truss project considering or avoiding this influences without raising budget on final design / Mestrado / Estruturas e Geotécnica / Mestra em Engenharia Civil
15

Marcuse, maskinen och människan : Hur den moderna tekniken intensifierar förnuftets instrumentalisering

Ramberg, Svante January 2024 (has links)
This paper considers the way Herbert Marcuse’s re-formulation of the instrumental reason as a technical reason can be understood as an intensification or acceleration of some of the themes presented by Theodor W. Adorno and Max Horkheimer in The Dialectics of Enlightenment. By reading Marcuse´s The One-Dimensional Man in dialogue with Martin Heidegger’s The Question Concerning Technology, the paper explores a thesis that Marcuse draws on concepts from Heidegger, especially Ge-stell and Bestand, in his notion of the “technical reason” and “technological rationality” to think and think beyond modern technology. By positing modern technology as the focal point of the instrumentalization of reason, Marcuse sheds light of historical and contemporary problems with human thinking. The staging of this conversation with Marcuse and Heidegger that never really took place allows the paper to fully explore and understand Marcuse’s invoking of the aesthetical dimension, as well as his re-appropriation of Freudian terminology, as a model to re-establish negative thinking as a necessary counteraction to the one-dimensional positive thinking that is dominating private and public sphere.
16

Usinabilité d'aciers inoxydables type 316 L : application au micro-fraisage / Machinabilitty of stainless steel 316L type : application in micro-milling

Guyout, Laurent 28 January 2014 (has links)
Le micro-fraisage (diamètre fraise < 1 mm) permet l’usinage précis de structures en 3D, à des dimensions micrométriques, dans desmatériaux d’ingénierie, se plaçant aux frontières de deux mondes : d’une part, le fraisage traditionnel appelé « fraisage macro » et d’autre part,la micro-fabrication et ses techniques dites de « salle blanche ».L'étude innovante porte sur le micro-fraisage d’aciers inoxydables 316L avec des micro-fraises cylindriques en carbure de tungstèneavec un équipement industriel (machine outil commercialisée et non optimisée) permet d’accentuer les nombreuses difficultés technologiquesliées à la mise en oeuvre du micro-fraisage et d’effectuer directement un transfert de compétences vers l’industrie. L’acier 316L(biocompatible, réputé de difficilement usinable) n’a jamais été étudié en micro-fraisage.L’étude aborde, au travers de neufs ratios caractéristiques du micro-fraisage, les problématiques de choix de moyens et de méthodespour caractériser la technique du micro-fraisage.Après analyses des paramètres de l’étude et des caractérisations des usinages, la définition géométrique optimale d’une micro-fraiseinnovante est proposée. Sa tenue en service est validée par des tests en usinage dans l’acier 316L, répondant ainsi, à une problématique decoupe négative à basse vitesse de coupe avec des effets d’échelle du matériau.Une originalité de l’étude est d’aborder l’effet de la population inclusionnaire visant à améliorer l’usinabilité. En comparant lesrésultats obtenus par micro-fraisage de 2 nuances d’acier 316L, la population inclusionnaire de l’acier 316L n’est pas identifiée comme unfacteur améliorant l’usinabilité à l’échelle de la coupe micro. / The micro-milling ( tool diameter < 1 mm) target the precise machining of 3D structures to micrometric dimensions, in engineeringmaterials, to be placed at the borders of two worlds : the one hand , the traditional milling called "macro milling" and other hand, the microfabricationand its so-called "clean room" techniques.The innovative study focuses on the micro-milling of 316L steel with carbide micro end mills with industrial equipment (machine toolmarketed unoptimized) can caricature the many technological challenges related to the implementation of the micro-milling and make a directtransfer of skills to the industry. 316L steel (biocompatible, reputed difficult to machine) has never been studied in micro-milling.The study looks at ratios through new features of the micro-milling, the problems of choice of means and methods to characterizemicro-milling.After analysis study parameters and machined parts, the optimal geometric definition of an innovative micro end mill is proposed.Service behavior is validated by testing machining in 316L steel, responding to a question of negative cutting with low cutting speeds andscale effects of the material.An originality of the study is to address the effect of the inclusion population to improve machinability. Comparing the resultsobtained by micro-milling two 316L steel grade, the inclusion population of 316L steel is not identified as a factor improving themachinability cutting at micro scale.
17

Letištní terminál / Airport Terminal

Pospíšilová, Vendula January 2019 (has links)
The diploma thesis is focused on a proposal and review of load-carrying steel structure of the airport terminal. The object is located in Zlín. It is a building of a rectangular plan with a ground plan dimensions of 75.0 x 54.0 m. The hall contains 10 main frames spaced by 6.0 m. The total height of the object is variable from 11.5 m to 19.9 m. The part of the construction is composite steel – concrete floor structure with a ground plan dimensions of 75.0 m x 27.0 m. The spatial rigidity of the construction is obtain by bracing. The cladding of the roof and the side walls is designed by sendwich panels, the cladding of the face walls is made by the glass facade system.

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