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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.
21

Estudo do comportamento mecânico em baixas temperaturas do Inconel 625 encruado / Studying the mechanical behavior of Inconel 625 cold drawn in low temperatures

Clovis de Oliveira Junior 07 December 2018 (has links)
As recentes descobertas de reservas de petróleo no pré-sal, representam uma grande oportunidade e desafio para a Petrobrás e demais indústrias de exploração e extração do petróleo. As exigências quanto aos materiais mais resistentes à corrosão e que conciliam boa resistência mecânica são cada vez maiores, devido aos constantes esforços dinâmicos que os equipamentos estarão sujeitos, pois os componentes estruturais serão submetidos à grande lâmina de água, ocorrência que as companhias exploradoras terão que superar. A otimização de materiais e equipamentos que podem melhorar a performance nas explorações do pré-sal tem sido a grande busca do setor nos últimos anos, muitos deles precisam ser testados e atestados quanto sua resistência à propagação de trincas, uma vez que, serão submetidos a oscilações devido as movimentações das marés e as condições de alta severidade a que serão expostos. Para suportar as condições de exposições com H2S, resistência a corrosão por pitting e resistência mecânica, porcas e parafusos têm sido fabricados com o Inconel 625, essas peças são estruturais e de extrema importância para a prospecção do petróleo. Após todas as etapas de fabricação, conformação, tratamento térmico e laminação a frio, o material foi caracterizado, realizou-se ensaio de metalografia que apresentou tamanhos de grão 7 e 8 conforme norma ASTM E112. Uma das premissas para a realização desse trabalho está nas condições que o material será exposto em situações acidentais, conforme informações da própria Petrobrás, em caso de vazamentos, os do tipo estruturais podem ser submetidos a temperaturas criogênicas de -100°C, -120°C e até -190°C devido ao vazamento de gases. Assim, o material foi caracterizado em temperaturas criogênicas através dos ensaios de tração, impacto e de CTOD. No ensaio de tração foi observado para as diferentes temperaturas criogênicas que apesar do aumento na resistência do material, da ordem de 787 MPa, o Inconel 625 manteve um alongamento acima de 40%. Nos resultados de Impacto a tenacidade se manteve acima de 200 J e não foi notada a curva de transição dúctil-frágil, mesmo para temperaturas tão baixas. No ensaio de CTOD utilizou-se corpos de prova de flexão (SENB) no ensaio de tenacidade à fratura, de acordo com a norma ASTM E1290.A componente plástica da abertura da boca do entalhe na temperatura de -190°C, pior caso, se manteve em 1,52 mm em média. Mediante a todos os resultados obtidos, pode-se afirmar que o aumento da resistência do Inconel 625 pelo processo de encruamento, não impossibilita sua aplicação para temperaturas criogênicas, mantendo sua capacidade de se deformar apreciavelmente antes de se romper. / Recently oil and gas discoveries in the Pre-Salt layer represent a huge exploration potential in Brazil, however, the technological challenges for the exploitation of these mineral resources are immense and therefore have motivated the development of studies looking for efficient methods and materials for their productions. The requirements about materials more corrosion resistance and mechanical resistance have been more frequently, as a result of high deep layer to explore the petroleum. The materials and equipment optimization to improve the performance in the pre-salt exploration have been the big search for oil and gas companies in the last years, but this materials must be testing in the crack propagation, because, this materials must resistance by oscillations, as consequence of ocean movements and others difficult situations that the materials must be support. To support H2S conditions, corrosion resistance by pitting corrosion and high mechanical resistance, bolts and nuts have been manufactured with Inconel 625, these products are structural and they are extreme importance to petroleum exploration. After all manufacturing operations, hot worked heat treatment and cold worked, the material was studied, and it was realized micrographic testing that result in grain size 7 and 8, in accordance ASTM E112 standard. One of premise to realized this paper are in the conditions that the material will be supported in accident situations, in agreement of Petrobras information, in the gases scape accidents, the structure materials can be exposed in cryogenically temperatures of -100°C, -120°C until -190°C. Therefore, the material was studied in cryogenically temperatures throw tensile testing, impact testing and CTOD. In the tensile testing was noted to different kind of cryogenically temperatures, same with more mechanical resistance, 787 MPa yield strength, the Inconel 625 has kept the 40% elongation. In the impact testing the notch toughness as kept above 200 J and it was not seen the transition ductile-Brittle in the low temperatures. In the CTOD testing was used bending test specimens (SENB) in the fracture toughness test for the Inconel 625, in agreement with the ASTM E1290 standard. The specimens was testing in tension and CTOD test in low temperatures: -100°C, -120°C and -190°C.The Clip gage displacement was recorded in the -190°C temperature with 1,52 mm average, this is the worse situation. Analyzing all the results, can be considered that the growth mechanical resistance of Inconel 625 by cold worked process, allow your application with cryogenically situations and the material has kept your ability to be well deformed before the crack.
22

Máscaras e mecanicismos: um estudo sobre os princípios da animação cinematográfica do desenho

Pereira, Simone de Novaes Costa 21 March 2017 (has links)
Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2017-05-09T13:27:47Z No. of bitstreams: 1 Simone de Novaes Costa Pereira_.pdf: 2594210 bytes, checksum: 40aa0222aecb8da7a5496942ef9f2246 (MD5) / Made available in DSpace on 2017-05-09T13:27:47Z (GMT). No. of bitstreams: 1 Simone de Novaes Costa Pereira_.pdf: 2594210 bytes, checksum: 40aa0222aecb8da7a5496942ef9f2246 (MD5) Previous issue date: 2017-03-21 / Nenhuma / A presente dissertação tem como objetivo conhecer o modo de ser da animação do desenho por meio da compreensão e observação dos princípios fundamentais Disney da animação cinematográfica. O método intuitivo, praticado por Henri Bergson, constitui o principal alicerce deste trabalho, no sentido de promover um estudo que tem como propósito compreender os modos de ser e de agir do objeto, tendo em conta suas duas tendências, virtual e atual. O conjunto dos doze princípios fundamentais é estudado a partir de uma abordagem tecnocultural, cujo enfoque reside na tentativa de apreender como técnicas e sensibilidades se transformam mutuamente. O conceito de imagem-movimento de Deleuze é fundamental na pesquisa, uma vez que os princípios são considerados tendo em conta uma dimensão relativa, referente às formalidades das operações no cinema, e uma dimensão absoluta, na qual se manifestam os regimes da imagem-movimento. A observação da dimensão absoluta se dá a partir da cartografia dos princípios, de acordo com a elaboração de duas constelações – Máscaras e Mecanicismos – em cenas de quatro longas-metragens de animação, quais sejam: Branca de Neve e os Sete Anões (EUA, 1937), Toy Story (EUA, 1995), A Viagem de Chihiro (Japão, 2001) e O Menino e o Mundo (Brasil, 2013). / The present dissertation aims to know the way of being of the drawn animation through the understanding and observation of the Disney’s fundamental principles of the cinematographic animation. The intuitive method, practiced by Henri Bergson, constitutes the main foundation of this work, in the sense of promoting a study whose purpose is to understand the ways of being and acting of the object, taking into account its two tendencies, virtual and current. The set of twelve fundamental principles is studied from a technocultural approach, whose focus lies in the attempt to learn how techniques and sensibilities transform each other. Deleuze's concept of image-movement is fundamental in the research, since the principles are considered taking into account a relative dimension, referring to the formalities of the operations in the cinema, and an absolute dimension, in which the regimes of the image-movement manifest themselves. The observation of the absolute dimension is based on the cartography of the principles, according to the elaboration of two constellations - Masks and Mechanics - in scenes of four animated feature films, namely: Snow White and the Seven Dwarfs (USA, 1937 ), Toy Story (USA, 1995), Spirited Away (Japan, 2001) and Boy and the World (Brazil, 2013).
23

The Drawn Subject: Meaning and the Moving Drawing

Williamson, Naomi, naomiruthwilliamson@mac.com January 2007 (has links)
Using the vehicle of hand drawn animation, this is an ongoing reflection of instances that repeat themselves to a point beyond the humorous and back. The Myth of Sisyphus 'The Gods had condemned Sisyphus to ceaselessly rolling a rock to the top of a mountain, whence the stone would fall back on its own weight. They had thought with some reason that there was no more dreadful punishment than futile and hopeless labour.' Albert Camus- The Myth of Sisyphus By observing and illustrating assiduous daily gestures and events our absurd hero is revealed: this protagonist, be it object or human consciously and often unconsciously lives within a relentless finite experience. As the same moment is duplicated, the
24

Two essays of the market friction effects on asset prices: evidence from syndicated loan and futures markets

吳偉劭, Wu, Wei-Shao Unknown Date (has links)
Two essays are comprised in this dissertation to explore how market friction affects the processes of price formation. The first essay investigates on both theoretical and empirical bases how segmentation of communication amongst potential lenders can influence loan contracts. Two cases are considered. The first one assumes that potential lenders can freely communicate with each other; the second one assumes that each potential lender can only observe the decisions of its predecessors. I show theoretically that the ex post observed interest rate will be higher and the probability of syndication failure will be lower if the potential lenders cannot communicate freely with each other. These predictions are confirmed by my empirical work. Using a novel proxy, relational distance, for the segmentation of communication, I show that the larger the relational distance, the higher is the loan spread and the lower is the probability of syndication failure. In addition, the relational distance is positively correlated with the probability of the existence of non-price contract terms, such as the requirement for collateral and guarantees. My conclusions are found to be robust to endogeneity issues, potentially omitted variables and alternative model specifications. The second essay focuses on the informational effects between futures market and its spot market. Intraday data are used to investigate the lead-lag relationship between the TX returns, the TX trading activity and the TAIEX stock index returns. I focus on the transmission direction and the source of information and find that there are specific lead-lag relationships between futures returns and spot returns, in addition to the contemporaneous relationship predicted by carry-cost theory and efficient market theory. The results show that futures returns significantly lead spot returns, which suggests that informed trades occur in the futures market and makes information flows from the futures market to the spot market. By distinguishing different types of futures traders and using private information, net open buy, as a proxy for futures trading activity, I found that the major source of informed trades is foreign institutional traders because their trading activity have predictive power for future movements in both spot and futures prices. In contrary, traders in the other categories carry no information about the directional changes in both spot and futures prices.
25

2D Aesthetics with a 3D Pipeline : Achieving a 2D Aesthetic with 3D Geometry

Nilsson, Morgan, Lundmark, Andreas January 2017 (has links)
This thesis evaluates and tests different methods utilized to produce a 2D aesthetic within a 3D pipeline, as in, converting 3D geometry to an aesthetic that is similar to hand-drawn classic films such as Snow White And The Seven Dwarfs. This thesis explores methods to produce both exterior and interior lines that indicate shape and form of 3D models, the conclusion from the tested methods leaves with the statement that it is unlikely the human factor will be ever entirely replaced by automated solutions, and instead a mixed approach with shader relied solutions and involvement of texturing techniques which provides artistic controls where necessary, is deemed to be the most effective way of preserving the hand-drawn 2D aesthetic within a 3D-pipeline.
26

Optimalizace výroby součásti na hlubokotažném lisu / Optimization of components production on draw press

Rérych, Pavel January 2019 (has links)
The diploma thesis present technology production of draining outlet. This is a rectangular deep drawn part, where basic shape is formed in two towing operations now. The used material is an austenitic stainless steel 17 240 with thickness 1 mm. According to the entry documentation the production technology was not change – current technology (it means drawing without thinning the wall) is most suitable. Based on technological and control calculations two-operations production was determined, which will take place in the united conventional instrument. The hydraulic press with marking Dieffenbacher PO250, which has a magnetic tool clamping, per stroke will perform here both operations. The payback was calculated for yearlong production 50 000 pieces after 0,8 years. The proposed production will make the current production more efficient including economic benefits.
27

Optimalizace procesu výroby vpusti / Optimization of production process of drain

Staněk, Vojtěch January 2012 (has links)
The project looks for a solution to optimalization of rotational deep drawn part with flange production. It deals with sewerage drain, which is produced by conventional tool to two deep drawing operations. The used material is austenitic Cr-Ni stainless steel 1.4301. Suitability of this material for deep drawing operations was considered by means of the tensile test and the Erichsen test. On the bases of these results, serializability of production and theoretic relationships for determination of number of deep drawing operations, it was decided upon one operation serial production, by conventional tool without attenuation thickness of sheet. Production will take place on hydraulic press Dieffenbacher PO250 with magnetic tool fastening. The deep drawing tool was designed and constructed. For series of 2 000 units per year the rate of return was calculated after 4,7 years, while using the punch from the current second deep drawing operation it was calculated after 3,4 years.
28

Campbell & The Cryptid: Mindfulness and Mediality

Buffkin, Elaina 01 January 2024 (has links) (PDF)
Campbell & The Cryptid is a short film that intertwines the bittersweet intensity of imagination with the nostalgic medium of hand drawn two-dimensional animation. Campbell is an eleven-year-old girl who loves adventure and spending time with her brother. But when he moves away, she carries on her explorations on her own. This leads her to discover a strange friend in the woods. The experience helps her understand that the unknown is not always as bad as imagined. Influences on the artistic direction include irreverent media such as Calvin & Hobbes, as well as more speculative works such as Over the Garden Wall to establish both the charm of youth and the authenticity of introspection.
29

Lire Quino : poétique des formes brèves de la littérature dessinée dans la presse argentine (1954-1976) / Reading Quino : poetics of drawn literature brief forms in argentinian presse (1954-1976)

Latxague, Claire 29 November 2011 (has links)
De 1954 à 1976, l'œuvre de Quino paraît essentiellement dans la presse argentine. Très vite, l'humoriste est reconnu de la profession et rejoint les pages de quelques-uns des plus grands périodiques d'humour et d'actualité de l'époque. S'adaptant à différentes lignes éditoriales, il explore plusieurs courants comiques, du burlesque à l'absurde, en passant par la satire d'une société en crise. Le rythme de publication soutenu et la variété des formes employées par l'humoriste – strip, planche et dessin unique – sont propices à l'élaboration d'une poétique de la brièveté. L'œuvre de Quino se construit dans une dynamique de répétition et de variation qui revisite la tradition du dessin humoristique de presse et thématise les conditions de sa création / From 1954 to 1976, Quino's work is essentially published in argentinian press. The humorist is very soon acknowledged by his profession and joins the pages of some of the most important journals and magazines of humor and information at this time. Adapting his creation to different editorial lines, he explores several forms of comic, from slapstick to absurdity, and even the satirizing of a society in crisis. His intense rhythm of publication and the diversity of forms used by the humorist – strip, page and cartoon – are favorable to elaborate a poetics of briefness. Quino's work is elaborated in a dynamics of repetition and variation which revisits graphic humor tradition and thematizes the conditions of his creation. / De 1954 a 1976, la obra de Quino se publica principalmente en la prensa argentina. Muy pronto, el humorista recibe el reconocimiento de los profesionales del humor y accede a las páginas de algunos de los periódicos y revistas de humor y de actualidad más importantes de la época. Al adaptarse a diversas líneas editoriales, explora varias formas de comicidad, del burlesco al absurdo, pasando por la sátira de una sociedad en crisis. El ritmo de publicación intenso y la diversidad de formas empleadas por el humorista – tira, página y dibujo único – son propicios para elaborar una poética de la brevedad. La obra de Quino se construye en una dinámica de repetición y variación que revisita la tradición del humor gráfico y tematiza las condiciones de su creación.
30

Desenvolvimento de células eletroquímicas com impressão 3D e escrita direta em papel para aplicações analíticas e bioanalíticas / Development of electrochemical cells with 3D printing and direct writing on paper for applications analytical and bioanalytical

Dias, Anderson Almeida 03 June 2016 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-29T14:56:34Z No. of bitstreams: 2 Dissertação - Anderson Almeida Dias - 2016.pdf: 2267814 bytes, checksum: ee86b1492eb772ffa46bd1de1e5e9e4b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-29T14:56:55Z (GMT) No. of bitstreams: 2 Dissertação - Anderson Almeida Dias - 2016.pdf: 2267814 bytes, checksum: ee86b1492eb772ffa46bd1de1e5e9e4b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-29T14:56:55Z (GMT). No. of bitstreams: 2 Dissertação - Anderson Almeida Dias - 2016.pdf: 2267814 bytes, checksum: ee86b1492eb772ffa46bd1de1e5e9e4b (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-06-03 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / This manuscript describes development of batch injection analysis (BIA) cells using a 3D printer as well show the fabrication of pencil draw electrode on paper platform. Bia cells were employed on wall-jet configuration coupled with amperometric system. Bia systems were used to detect a product reaction obtained by paper-microreactor and determine ethanol in whiskey samples. Fabrication process using 3D printer was simple, fast (lower than four hours) and cost effectiveness (ca. $ 3.43 and 1.07 to the 1st and 2nd generation of Bia system, respectively). The 1st generation of Bia cell was production to be couple with commercial screen printed electrodes (SPEs) by DropSens (DropSens, DPR 710 model) and 2nd generation have support to put home-made electrodes. Both Bia cells, present a specific compartment to be coupled the micropipette. Paperbased microreactors (MOPs) were used with the 1st generation of Bia cell and the system was employed to measure glucose through the generation of hydrogen peroxide by the reaction of glucose with glucose oxidase and amperometric detection of H2O2 generated in the reaction at a potential of -0.25 V vs. Ag. In the same way of Bia cell, MOPs fabrication process is simpler, faster and cheaper (ca. $ 0.02 cent each). In general, the system shows a good linear response for concentration range between 1 to 10 mmo L-1. The limit of detection (LD) and quantification (LQ) found were 0.11 mmol L-1 and 0.38 mmol L-1, respectively. Besides, the measure of glucose using five different MOPs presented a good repeatability (RSD between 1.5 to 2.8%) and reproducibility (RSD = 0.66%). The 2nd generation of Bia cell was coupled with copper working electrode modified thermally and chemically. This cell was employed to determine the presence of ethanol in whisky sample using 1 mol L-1 NaOH as supporting electrolyte and potential of 0.45 V vs Ag / AgCl. The modified-electrode shows optimum stability to measure seventy minute of consecutive injection with RSD lower than 4.7%. A good linear response was obtained when concentration of ethanol ranged from 2.5 to 25% (v/v). The LD achieved was ca. 0.07% (v/v). Besides the Bia cells experiments, this work describes the fabrication process of alternative electrodes by hand drawing pencil on paper platform. Initially, the geometry of sensing electrodes was drawn using a graphic software and printed on paper surface. During printing process, toner lines were deposited on paper to delimit the electrode area. Then, the desire layout was draw using a pencil and laminated using benchtop laminator. This last step is necessary to make the electrical insulation. Fabrication process of alternative electrodes was simple, fast (~ 20 minutes) and cost effectiveness (ca. $ 0,023). Characterization of paper electrodes was made by cyclic voltammetry with potassium ferrocyanide (5 mmol L-1) in KCl solution (0.5 mol L-1). Besides, showed good peak separation (ΔEp) ca. 238 mV and excellent reproducibility. The RSD was lower than 2.25% to five different electrodes. / Esta dissertação apresenta o desenvolvimento de células para análise por injeção em batelada (BIA, do inglês “batch injection analysis”) mediante uso de uma impressora 3D assim como a fabricação de eletrodos utilizando uma técnica de escrita direta em papel. As células BIA foram utilizadas com detecção eletroquímica, visando a análise de um produto de reação realizada em microrreatores de papel e, também, de etanol em amostras de uísque. As células BIA, fabricadas no laboratório por meio de uma impressora 3D, apresentaram baixo custo (cerca de R$ 12,00 e R$ 3,75 para 1° e 2° geração respectivamente), fabricação rápida (cerca de 4 horas e 1 hora e 40 minutos para 1° e 2° geração respectivamente) e robustez. Ambas as células BIA foram utilizadas com detecção amperométrica (DA) e apresentam configuração wall-jet. A 1° geração BIA possui suporte para eletrodos serigrafados (SPEs) comerciais da DropSens e pipeta eletrônica e a 2° geração BIA possui suporte para eletrodos convencionais construídos no laboratório e pipeta eletrônica. Os microrreatores à base de papel (MOPs) foram vinculados à 1° geração da célula BIA, este sistema foi utilizado para quantificação de glicose a partir da geração de peróxido de hidrogênio mediante a reação da glicose com glicose oxidase, e detecção do H2O2 gerado com SPEs de carbono modificado com azul da prússia (DropSens, modelo DPR 710) em um potencial de -0,25 V versus Ag. A confecção dos MOPs é simples, rápida (2 horas e 30 minutos) e de baixo custo (cerca de R$ 0,06 a unidade). Para a fabricação dos microrreatores a base de papel, primeiramente foi realizada a modificação química da superfície do papel. Para, em seguida, efetuar a imobilização covalente da enzima. Os ensaios realizados utilizando os MOPs vinculados a 1° geração da célula BIA com detecção amperométrica (BIADA) apresentaram linearidade para faixa de concentração entre 1 e 10 mmol L-1 (R² = 0,990), alta repetitividade (DPR entre 1,5% e 2,8%) e elevada reprodutibilidade (DPR = 0,66%) para 5 microrreatores. Os limites de detecção e quantificação obtidos foram de 0,11 mmo L-1 e 0,38 mmol L-1 respectivamente. A 2° geração da célula BIA foi acoplada com eletrodo de trabalho (ET) de cobre modificado por tratamento químico / térmico e utilizada para verificação de adulteração em uísques através da quantificação de etanol utilizando NaOH 1 mol L-1 como eletrólito suporte e potencial de 0,45 V versus Ag/AgCl. Os ensaios utilizando a 2° geração da célula BIA-DA apresentaram linearidade para faixa de concentração entre 2,5 e 25 % v/v de etanol (R² = 0,998) e elevada estabilidade (DPR = 4,7%) para aproximadamente 70 minutos de injeções consecutivas. O limite de detecção obtido para o etanol foi de 0,07% (v/v). Os eletrodos em plataforma de papel foram produzidos através da pintura direta com lápis. Para a fabricação destes dispositivos, primeiramente o layout dos eletrodos são impressos no papel para definir a área do desenho dos eletrodos. Em seguida os eletrodos são pintados com lápis, depois os dispositivos são plastificados com polaseal com o objetivo de isolar os contatos e delimitar a área dos eletrodos. A confecção destes eletrodos é rápida (~ 20 minutos) e de baixo custo (R$ 0,082 a unidade). Os eletrodos foram caracterizados utilizando voltametria cíclica com ferrocianeto de potássio 5 mmol L-1 solubilizado em KCl 0,5 mol L-1. Estes dispositivos apresentaram elevada reprodutibilidade (DPR = 2,25%) para 5 eletrodos distintos.

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