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Made available in DSpace on 2017-07-21T20:42:33Z (GMT). No. of bitstreams: 1 Ariane Emi Yonekubo.pdf: 14387414 bytes, checksum: 915c8e68747eb2fccc91d9829eb93469 (MD5) Previous issue date: 2010-09-10 / Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná / Superduplex stainless steels are often used in applications where is necessary high mechanical strength combined with corrosion resistance. They are formed by a ferrite (a) BCC and austenite (g) FCC mixture, have a yield stress about of the double of the austenitic and ferritic stainless steels, larger plasticity that the one of the martensitic and precipitation hardening, high resistance to the intergranular corrosion, pitting and the stress-corrosion cracking. However, during hot deformation, these steels recrystallize forming a lamellar microstructure with anisotropic properties. Through the high energy milling, accomplished with Spex, Attritor and Planetary ball mills, it was aimed to obtain a homogeneous and with fine grains superduplex stainless steel. Initially, in this work, chips were made by machining of a UR 52N+ (UNS S32520) commercial superduplex stainless steel rolled sheet, without previous heat treatment, which will be submitted to the high energy milling adjusting the milling parameters and subsequently it was accomplished the heat treatment at temperatures of 1200 °C e 1250 °C for 1 hour in argon atmosphere and 1200 °C for 1 hour in argon with 2% of hydrogen. The obtained powders were analyzed by scanning electron microscopy, observing that the smaller and more homogeneous particles were obtained by Spex milling for 16 and 32 hour; the compressibility curve showed that after a long time milling, the material can present compaction difficulty and this way, great final porosity. The x ray diffraction presented peaks with a bottom widening due to the small size of the obtained particles. The porosity percentage determined by optical microscopy, reduced after heat treatment at 1200 °C in argon atmosphere with 2% hydrogen, however the scanning electron microscopy showed a fine porosity that could not be observed only in the optical microscopy analysis. The differential scanning calorimetry and the differential thermal analysis showed formation and revertion of strain induced martensite peaks and using atomic force microscopy, magnetic ferrite and paramagnetic austenite phases were observed by a non destructive test. The milling of the chips in Spex milling for 16 hours provided a refined microstructure with equiaxial grains and size of 11 μm after heat treatment at 1200 °C for 1 hour in argon atmosphere. / Aços inoxidáveis dúplex são frequentemente utilizados em aplicações onde é necessária elevada resistência mecânica combinada a resistência à corrosão. São formados por uma mistura de ferrita (a) CCC e austenita (g) CFC, apresentam limite de escoamento cerca de o dobro dos aços inoxidáveis austeníticos e ferríticos, maior plasticidade que a dos martensíticos e dos endurecíveis por precipitação, elevada resistência à corrosão intergranular, à corrosão localizada e à corrosão sob tensão. Porém, durante a deformação a quente, estes aços recristalizam-se formando uma microestrutura lamelar com propriedades anisotrópicas. Através da moagem de alta energia, realizada com moinhos de bolas dos tipos Spex, Attritor e Planetário, objetivou-se obter um aço inoxidável superdúplex de grãos homogêneos equiaxiais e finos. Inicialmente, neste trabalho, foram feitos cavacos por usinagem da chapa laminada de um aço inoxidável superdúplex comercial UNS S32520 (UR 52N+), sem tratamento térmico prévio, os quais foram submetidos à moagem de alta energia acertando-se os parâmetros de moagem e posteriormente realizou-se o tratamento térmico em temperaturas de 1200 °C e 1250 °C, por tempo de 1 hora em atmosfera de argônio, e a 1200 °C por 1 hora em atmosfera de argônio com 2% de hidrogênio. Analisaram-se os pós obtidos por microscopia eletrônica de varredura, observando que as partículas menores e mais homogêneas foram obtidas após as moagens no Spex por 16 e 32 horas; a curva de compressibilidade mostrou que após um tempo muito grande de moagem, o material pode apresentar dificuldade de compactação e desta maneira, maior porosidade final. A difração de raios x apresentou picos com alargamento na base devido ao tamanho pequeno de partículas obtidas. A porcentagem de porosidade, determinada por micrografia óptica, diminuiu após tratamento térmico a 1200 °C em atmosfera de argônio com 2% de hidrogênio,porém a microscopia eletrônica de varredura mostrou uma porosidade fina que não pôde ser observada somente através da microscopia óptica. As análises térmicas por calorimetria exploratória diferencial e por análise térmica diferencial mostraram picos de formação e reversão de martensita induzida por deformação e pela microscopia de força atômica, foram observadas as fases ferrita magnética e austenita paramagnética por ensaio não destrutivo. A moagem dos cavacos em moinho do tipo Spex por 16 horas forneceu uma microestrutura refinada com grãos equiaxiais e tamanho de 11 μm após tratamento térmico a 1200 °C por 1 hora em atmosfera de argônio.

Made available in DSpace on 2016-04-27T17:27:13Z (GMT). No. of bitstreams: 1 John Stuart Mill e o psicologismo.pdf: 586444 bytes, checksum: 4f8cde60a2889debc936f6d16408307e (MD5) Previous issue date: 2006-05-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents the logic and semantic of John Stuart Mill relating them, on the one hand, to the psychological nominalist tradition represented by John Locke´s theory of ideas, and, on the other hand, to the forthcoming logic semantic discussions of XIX century, mainly from Frege´s philosophy. According to our hypothesis, in opposition to an established interpretative tradition, Mill was responsible for significant theses, among others, in favor of the logicist efforts and anti-psychologists who marked most of the later discussions on the nature of logic. On the one hand, Mill´s criticism to the thesis according to which the significance of language terms are ideas (what he calls conceptualism), in addition to his clear view in distinguishing mental processes in the reasoning act of objective reasons involved in the inferences correction, constituted, according to our conclusions, important positive influence sources, not just to Frege´s philosophy, but to a whole philosophycal tradition that came to contemporary analytical philosophy. The work is divided in three chapters. In the first chapter, important elements of Mill´s logic and semantics are presented, such as: the definition of logic as a proof science, the relationship between logic and language, theory of connotation and some propositions. The second chapter deals with Mill´s criticism of the psychological semantic model represented by, among others, Locke. The third chapter aims to the question whether, from the point of view of Fregean logicism, Mill can be considered a psychologist / Este trabalho apresenta a lógica e a semântica de John Stuart Mill relacionando-as, por um lado, à tradição psicológio-nominalista representada pela teoria das idéias de John Locke e, por outro, aos desdobramentos das discussões lógico-semânticas do século XIX, sobretudo a partir da filosofia de Frege. De acordo com nossa hipótese, ao contrário do que toda uma tradição interpretativa estabeleceu, Mill, como que por detrás de algumas posturas ultrapassadas, foi responsável por teses significativas, entre outras coisas, em favor dos esforços logicistas e antipsicologistas que marcaram boa parte das discussões posteriores acerca da natureza da lógica. A crítica que Mill realiza à tese segundo a qual o significados dos termos da linguagem são idéias (o que ele chama de conceitualismo), aliada à sua clareza em distinguir processos mentais envolvidos no ato do raciocínio, das razões objetivas envolvidas na correção das inferências, constituíram, de acordo com nossas conclusões, importantes fontes de influência positiva, não só para a filosofia de Frege, mas para toda uma tradição filosófica que veio a desembocar na filosofia analítica contemporânea. O trabalho é dividido em três capítulos. No primeiro, são apresentados alguns elementos importantes da lógica e da semântica millianas, tais como: definição de lógica enquanto ciência da prova, relação entre lógica e linguagem, teoria da conotação e proposições meramente verbais. O segundo, trata da crítica de Mill ao modelo semântico psicológico representado, entre outros, por Locke. O terceiro, busca responder se, a partir do ponto de vista do logicismo fregeano, Mill pode ser considerado um psicologista

M.Ing. / This research dissertation highlights the important role of scheduling in a production environment. The functioning of an integrated iron and steel works is discussed. The importance of production scheduling in this environment is shown, followed by a literature survey of strip mill production scheduling models. Thereafter a model is introduced that aids in the production scheduling of plate via coil in a hot strip mill. Finally the benefits of the scheduling model are shown.

In 1948 and 1949, three doctoral students in sociology and anthropology conducted ethnographic fieldwork in York, SC (called Kent), a mill town. Through interviews, white town elites, black mill workers, and white mill workers revealed their lives to the scholars. What resulted were three remarkable studies on southern town life in the immediate post World War II period. Although segregation had begun to weaken in the face of postwar socioecomic change, it still held whites and blacks in its grip. The “thick description” of community life provided by the ethnographic interviews, as well as the authors’ analysis of life in York, makes these three books invaluable still to scholars of the history and sociology of the South.

En inventering i början av 1970-talet visade på 255 existerande väderkvarnar (100 stolpkvarnar, 155 hättkvarnar) på Gotland i varierande skick. En småindustriinventering 2001 bekräftade antalet ungefärligt. Dessa inventeringar av Gotlands kvarnbestånd fokuserade helt på det exteriöra och förbisåg kvarnarnas interiörer. Ingen heltäckande inventering har således gjorts av väderkvarnarnas på Gotland interiörer. Många står och ruttnar bort, en del byggs om och många har redan byggts om till fritidsboenden. Varken Länsstyrelsen Gotlands län eller Region Gotland (Gotlands kommun) har i nuläget någon plan för kvarnarna. Medvetenheten och kunskapen är påtagligt liten om kvarnverken i dessa kvarnar, och denna omedvetenhet eller okunskap kan leda till ett ofrivilligt ointresse, inte minst hos beslutsfattare, med den effekten att för eftervärlden värdefull dokumentation inte genomförs, och naturligtvis även att många kvarnverk går förlorade - för alltid. Vi och våra efterkommande går då miste om kunskap om vårt förflutna, om olika historiska uttryck vad gäller teknikhistoria från olika tidsperioder och regioner. Kanske får vi kvar en mindre mängd exempel som talar till oss från det förflutna och som säger ”så här var det”, men verkligheten var mer varierad. Eftersom forskningen om Gotlands väderkvarnar är eftersatt vet vi inte vilka som byggde väderkvarnarna, medan man på andra håll vet namn på kvarnmästare och kvarnmästarfamiljer. Kvarnarna utgör spår efter en månghundraårig hantverkstradition vars hantverksmässiga uttryck nådde sin kulmen under 1800-talet, det århundrade då de flesta av kvarnarna i undersökningen uppfördes i. Denna omedvetenhet eller okunskap om kvarnverken kan leda till tanken och föreställningen att en kvarns interiör bara är ”en sak och inget annat”, vilket i sin tur kan leda till tanken eller beslutsfattandet, att det räcker med att bevara en utvald liten skara kvarnar för eftervärlden, som ska stå och säga till betraktaren, att ”så här var det”, men om en ny tanke lyckas bli etablerad, att det inte alls är ”en sak och inget annat”, utan ”många olika uttryck, inget kvarnverk är riktigt likt ett annat”, blir bevaringsproblematiken genast mer komplicerad, och det är den nya tanken författaren vill etablera hos läsare av olika slag. Författaren har dokumenterat de nitton kvarvarande hättkvarnarna av trä på Gotland (av vilka tolv bedömdes ha tillräckligt med och tillräckligt bevarat kvarnverk i sig för att vara med i undersökningen) i syfte att ge en översiktlig samt jämförande bild av teknikhistoriska uttryck och värden som finns i dem. De delar av kvarnverken som behandlas är: kronhjul, stjärnhjul, krondrev, stjärndrev, pärsar och mötet mellan kvarnhuset och hättan. Undersökningen visar på en mångfald och en varietet i kvarnarna och kvarnverken, att kvarninteriörerna istället för att bara vara ”en sak och inget annat”, är ”många olika uttryck, inget kvarnverk är riktigt likt ett annat”. Undersökningen visar också på skillnader i tidsuttryck vad gäller material och konstruktion, och en teknisk utveckling har på så vis kunnat spåras, bl.a. i och med gjutjärnets intåg under slutet av 1800-talet. / An inventory in the early 1970’s showed the existence of 255 windmills (100 postmills, 155 cap-mills) on the Swedish island of Gotland, in varying condition. An inventory of small scale industry on the island in 2001 confirmed the number roughly. These inventories focused on the exteriors and overlooked the interiors. Many of these windmills now rot away, some are being altered and many have been turned into summer houses. Neither Länsstyrelsen Gotlands län (the county administrative board) nor Region Gotland (the local authority) have at present any plan for the windmills. The awareness and knowledge of the machinery in these windmills is evidently small, and this unawareness or ignorance may lead to an involuntary disinterest, not least among decision-makers, to the effect that valuable documentation for the posterity is not being accomplished, and naturally also that many machineries are lost – for ever. We and our descendants then lose knowledge of our past, of different historical expressions of technique-history from different periods and regions. Perhaps a smaller amount of examples will remain to speak to us from the past and say: “This is how it was”, but reality was more diversified. Since the research in windmills on Gotland is neglected, we don’t even know who built them, while in other places names of millwrights or millwright families are known. We have here a craftsmanship of centuries-old tradition, even a neglected profession, whose expressions in craftsmanship culminated in the 19th century, the century in which most of the windmills in this survey were built. This unawareness or ignorance of the windmill machinery may lead to the thought or the notion that the interior of a windmill is just “one thing and nothing else”, which in turn leads to the thought or the decision-making, that it will be enough to preserve just a small amount of chosen windmills for the posterity, which will stand there and tell the onlookers: “This is how it was”, but if a new thought manages to be established, that it isn’t just “one thing and nothing else”, but “many different expressions, no windmill machinery resembles another”, then the preservation problems immediately become more complex, and that is the new thought the author would like to establish among different kinds of readers. The author have documented the nineteen remaining wooden cap-mills on Gotland (twelve of which were judged had enough of and sufficiently preserved machinery to take part in the survey) with the aim to provide a lucid and comparative picture of what technique-historical expressions and values there are in the machineries, expressions and values which heretofore have not been given their due attention. The parts of the windmill machineries which are dealt with are: brake wheels, spur wheels, brake wheel wallowers, spur wheel wallowers, brakes and the meeting between the millhouse and the cap. The survey shows an existing variety in the windmills and their machineries, that these mill interiors are not just “one thing and nothing else”, but rather “many different expressions, no windmill machinery resembles another”. The survey also shows different expressions in time when it comes to material and construction, and a technical development has thus been traced, for example with the entry of cast iron at the end of the 19th century.

Mondi Dynäs is a pulp and paper producer in the north of Sweden close to the town Kramfors. Last year Mondi Dynäs produced 231,404 tons of Kraft paper. In order to increase their production to 300,000 tons of paper per year this study was done in order to investigate how the increased biomass flow would affect the generation of steam along with the steam and condensate balance. This study started with a mapping of the current steam and condensate balance for one winter period January – Mars and one summer period July – September 2015. The resulting balance is used as reference period for the development of the future steam and condensate scenario where Mondi Dynäs will achieve the targeted production of 300,000 tons of paper per year. The future model shows that the future production of paper will give an abundance of biomass since the generation of steam will be more than sufficient. For the winter period the venting of steam over roof could be derived to 11.9 tons per hour and 34.4 tons per hour during the summer period. This can be compared to the current situation where the winter period gave an average steam blow out of 8.7 tons per hour and for the summer period 13.1 tons per hour. To utilize the accumulated energy from these energy streams, three different scenarios was studied. The first scenario were a future installation of a backpressure turbine along with a condensing turbine section. The new turbine would be attached to the highest pressure level at 65.5 bar and have a backpressure exhaust at 20 bar which will give a power of 7.6 MWe. The second scenario included the implementation of a new condensing turbine with the current system design for the steam network and boilers. This turbine would be attached to the 3.5 bar network and give the electricity power of 1.9 MWe. The third scenario included the installation of a new bark dryer. This would give Mondi Dynäs the possibility to sell bark to an external actor on the energy market. From derived figures in the future scenario model it would be possible to sell 108,144 MWh of bark while running the bark boiler. Mondi Dynäs AB is recommended to add a new condensing turbine to their steam network. The new turbine would be able to produce 1.9 MWe and need a cooling water flow of 190 tons of water per hour. Derived figures for the investment shows a NPV of 0.6 MEUR and the IRR value of 31 %

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We examined tree rings from cross-sections of shortleaf pine (Pinus echinata Mill.) timbers extracted from a house in Forsyth County, Georgia, that was reportedly built in the mid-19th Century during the Antebellum Period (pre-1860). Our goals were to (1) determine the probable construction year for the house to help assess its possible historical significance, and (2) create a new long-term reference chronology for the northern Georgia area where such chronologies are lacking. Sections of shortleaf pine were removed from the structure during a renovation project in 2001. Sixteen sections were used to build a floating tree-ring chronology 217 years in length from series that crossdated conclusively with other series both graphically via skeleton plots and statistically via COFECHA. We then statistically evaluated the probable absolute temporal placement of this chronology using several regional tree-ring chronologies from the southeastern U.S. A statistically significant (p , 0.0001) correlation between our chronology and a shortleaf pine chronology from Clemson, South Carolina, anchors our chronology between 1652–1868. Two missing rings are probable in the early portion of our chronology, but we currently do not have a sufficient number of samples to conclusively identify their exact placement. No cluster of outermost rings was found to support the reported construction date of 1851, although the outermost rings on 13 of 16 samples dated before 1851. This new chronology could aid further dating of wood from archaeological sites and historical structures, and establish an initial data set that could eventually provide important new insights about the climate of northern Georgia during the 17th–19th Centuries.

No description available.