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Annihilating the Cartesian Divide : Finding the Inhuman in Jeff VanderMeer's AnnihilationRosquist, Rasmus January 2019 (has links)
As posthumanist discourse attempts reposition the human as one of many subjects in relation to ecologies and other inhuman agencies, doing away with a Cartesian human exceptionalism is one of the key problems. From Haraway’s naturecultures, positing human culture as one of many, to Colebrook’s discussions of inhuman agencies, what ‘the human’ means to us is the heart of this theoretical field. In this paper I engage with theories within the discourse and posit them against a dialogue with Annihilation by Jeff Vandermeer, as well as with the ideas of George Bataille on how the human separated herself from other animals and in doing so created what we call Humanity. The aim is to find inhuman agencies and bring to light how they act upon the human, but also how perceiving the inhuman is, as Bataille writes, closed to us. What we find through a process and concept of annihilation of Humanity with the human, brought forth from a reading of the Biologist’s relation to the lighthouse and the tower in the novel, is that even though we may be able to perceive the inhuman, we might be always already anthropocentric in this perception. I suggest a reversal of Haraway’s term; culturenatures, as a way to understand this anthropocentric perception, in that just as our culture is borne from nature, other naturecultures are closed to us.
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Análise de formulações explícitas do coeficiente de perda de carga em condutos pressurizados / Analysis of explicit formulations of the pressure loss coefficient in pressurized conduitsPimenta, Bruna Dalcin 07 July 2017 (has links)
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / One of the parameters involved in the design of pressurized hydraulic systems is the pressure drop of the pipes. This verification can be performed through the Darcy-Weisbach formulation, which considers a coefficient of loss of charge (f) that can be measured by the implicit Colebrook-White equation. However, for this determination it is necessary to use numerical methods. Numerous explicit approaches have been proposed to estimate the "f", with different precisions and complexity. Considering the above, the objective of this work is to analyze the explicit approximations of the pressure loss coefficient for pressurized conduits in relation to the Colebrook-White formulation, through the relative performance and error index, determining the most accurate ones so that they can replace the standard Implied for the turbulent flow regime. It was analyzed 29 explicit equations in the literature, determining the coefficient of loss of charge through Reynolds number values in the range of 4x10³ ≤ Re ≤ 108 and relative roughness of 10-6 ≤ Ɛ / D ≤ 5x10-2, obtaining 160 points for each equation, totaling 4800 points. Statistical analysis was performed by the performance index (Id) and the relative error (ER) of the explicit equations in relation to Colebrook-White. The equations of Chen (1979), Shacham (1980), Sonnad Goudar (2006), Buzzelli (2008), Vantankhah and Kouchakzadeh (2008), Fang et al. (2011) and Offor and Alabi (2016a) apply for the entire range of 4x10³ ≤ Re ≤ 108 and 10-6 ≤ Ɛ / D ≤ 5x10-2, and presented high “Id” and high precision, the latter being highlighted by extreme precision, which is indicated to replace the use of the Colebrook-White standard approximation. / Um dos parâmetros envolvido no dimensionamento de sistemas hidráulicos pressurizados é a perda de carga das tubulações. Essa verificação pode ser realizada através da formulação de Darcy-Weisbach, que considera um coeficiente de perda de carga (f) que pode ser mensurado pela equação implícita de Colebrook-White. Porém, para essa determinação é necessário utilizar métodos numéricos. Numerosas aproximações explícitas têm sido propostas para estimar o “f”, com diferentes precisões e complexidade. Diante do exposto, o objetivo desse trabalho é analisar as aproximações explícitas do coeficiente de perda de carga para condutos pressurizados em relação a formulação de Colebrook-White, através do índice de desempenho e erro relativo, determinando as mais precisas para que possam substituir a padrão implícita, para o regime de fluxo turbulento. Foi analisado 29 equações explícitas presentes na literatura, determinando o coeficiente de perda de carga através de valores do número de Reynolds na faixa de 4x10³ ≤ Re ≤ 108 e rugosidade relativa de 10-6 ≤ Ɛ/D ≤ 5x10-2, obtendo 160 pontos para cada equação, totalizando 4800 pontos. A análise estatística foi realizada pelo índide de desempenho (Id) e pelo erro relativo (ER) das equações explícitas em relação à Colebrook-White. As equações de Chen (1979), Shacham (1980), Sonnad Goudar (2006), Buzzelli (2008), Vantankhah e Kouchakzadeh (2008), Fang et al. (2011) e Offor e Alabi (2016a) se aplicam para todo intervalo de 4x10³ ≤ Re ≤ 108 e 10-6 ≤ Ɛ/D ≤ 5x10-2, e apresentaram elevado Id e elevada precisão, destacando-se a última por extrema precisão, sendo esta a indicada para substituir o uso da aproximação padrão de Colebrook-White.
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