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1	Thermal analysis of energy beam using de-laval nozzle in plasma figuring process Yu, Nan January 2016 (has links) In 2012, plasma figuring was proven to be an alternative solution for the fabrication of large scale ultra-precise optical surfaces. Indeed, plasma figuring was successfully demonstrated on a metre class glass surface. The process was exceptionally rapid but residual errors were observed. This thesis addresses this issue by proposing an enhanced tool that provides a highly collimated plasma jet. The enhanced tool is characterized by a targeted material removal footprint in the range 1 to 5 mm FWHM. The energy beam is provided by an Inductively Coupled Plasma (ICP) torch equipped with a De-Laval nozzle. This thesis focuses on characterization and optimisation of the bespoke plasma torch and its plasma jet. Two research investigations were carried out using both numerical and experimental approaches. A novel CFD model was created to analyse and understand the behaviour of high temperature gas in the De-Laval nozzle. The numerical approach, that was based on appropriate profiles of temperature and velocity applied to the nozzle inlet, led to a significant reduction of computational resources. This model enabled to investigate the aerodynamic phenomena observed from the nozzle inlet up to the processed surface. Design rules and the effect of changing nozzle parameters were identified. Sensitivity analysis highlighted that the throat diameter is the most critical parameter. A challenging power dissipation analysis of the plasma torch was carried out. Temperature and flow rate in key components of the torch were measured. Experimental results enabled to calculate the power dissipation values for RF power up to 800 W and for the entire series of designed nozzles. This work enabled to scientifically understand the power dissipation mechanism in the bespoke ICP torches. In addition, by comparing the intensity of the power dissipation values, one nozzle was clearly identified as being more capable to provide a highly efficient plasma jet. 530.4
2	Interpreting the Sacred in <em>As You Like It</em>: Reading the "Book of Nature" from a Christian, Ecocritical Perspective Wendt, Candice Dee 17 July 2009 (has links) (PDF) Since the advent of the environmental crisis, some writers have raised concerns with the moral influence of Christian scripture and interpretive traditions, such as the medieval book of nature, a hermeneutic in which nature and scripture are "read" in reference to one another. Scripture, they argue, has tended to stifle sacred relationships with nature as a non-human other. This thesis argues that such perspectives are reductive of the sacred quality of scripture. Environmental perspectives should be concerned with the desacralization of religious texts in addition to nature. Chapter one suggests that two questions surrounding the medieval book of nature's history can help us address ways that such perspectives reduce religious interpretation of sacred texts. The first question is the tension between manifestation and proclamation, or the question of how scripture and nature reveal sacred meanings. The second is the problem of evil, or the question of where evil and suffering come from. It also proposes that Shakespeare's As You Like It and religious philosophy, particularly Paul Ricoeur's writings, can help us address these problems and provide a contemporary religious perspective of the "book of nature." Drawing on scenes in the play in which nature is "read" as a book and Ricoeur's essay on "Manifestation and Proclamation," chapter two argues how manifestation often works interdependently with proclamation. Chapter three discusses how anthropocentric worldviews in which natural entities are exploited also distort interpretive relationships with scripture. Overcoming desacralization requires giving up desires to suppress contingencies, particularly suffering, in nature and in interpreting religious texts. Only as the characters in As You Like It accept contingencies are they able to engage hidden sources of hope, which is comparable to the need to let go of mastery in interpretation Ricoeur describes. Chapter four discusses problems with attempts to uncover the origins of the environmental crisis by discussing what Ricoeur writes about the problems with theodicy and Jean-Luc Marion's phenomenology of evil. Assumptions that specific human origins for evil can be blamed confirm deceptively human-centered worldviews and can mask valuable messages about how to morally respond to suffering that are taught in Judeo-Christian narratives. As You Like It book of nature Paul Ricoeur Figuring the Sacred ecocriticism environmentalism Albert Borgmann Martin Heidegger The Question Concerning Technology The Anaximander Fragment Jean-Luc Marion Evil in Person logic of evil pastoral contingency ruach medieval exegesis ecotheology Manifestation and Proclamation the problem of evil Lynn White The Spell of the Sensuous Nature and Silence Classics Comparative Literature
3	Les cantates de Nicolaus Bruhns (1665-1697) / The cantatas of Nicolaus Bruhns (1665-1697) Fructus, Michel 03 December 2009 (has links) Nicolaus Bruhns (1665-1697) fut organiste à la Marienkirche de Husum (Schleswig-Holstein), et Kapellmeister au service des ducs de Schleswig-Holstein-Gottorf. Si nous ne possédons aujourd’hui qu’une poignée de ses pièces pour orgue (quatre praeludia et un choral-fantaisie), nous pouvons apprécier l’ingéniosité de cet auteur à travers sa production d’œuvres sacrées, douze cantates où règne une énergie comparable à celle de son professeur Dietrich Buxtehude.Soucieux de mieux cerner les enjeux de l’identité créatrice, nous proposerons une approche contradictoire, fondée sur deux conceptions opposées de l’œuvre d’art : elle est par voie de conséquence le produit d’une culture (parce qu’elle est liée au contexte artistique qui la précède, au regard des éléments qui la constituent et qui sont facilement identifiables dans les œuvres du passé, toute œuvre peut être perçue et pensée comme une synthèse de différents modèles, une forme d’aboutissement culturel), mais aussi le fruit d’une individualité (une œuvre d’art est une élaboration unique, indépendante de toute autre production, au regard des facteurs d’unité qui la structurent ; toute œuvre peut alors être perçue et pensée comme une entité autonome).Cette étude nous permettra de mettre à jour un soubassement de l’activité psychique : l’estimation de la distance entre le fixe et le muable. / Nicolaus Bruhns (1665-1697) was an organist at the Marienkirche in Husum (Schleswig-Holstein), and Kapellmeister to the dukes of Schleswig-Holstein-Gottorf. If we own today only a handful of his pieces for organ (four praeludia and a chorale-fantasia), we can appreciate the cleverness of this author through his production of sacred works, twelve cantatas where the energy which appears is similar to that of his professor Dietrich Buxtehude.With the concern to better define the stakes of creative identity, we shall put forward a contradictory approach based on two opposite conceptions of the work of art : it is in essence the product of a culture (since it is linked to the artistic context which precedes it, according to the elements which constitute it and which are easily identifiable in the works of the past, any work can be perceived and thought as a synthesis of various models, a form of cultural achievement), but also the result of individuality (a work of art is a unique construction, independent from any other production according to the factors of unity which structure it ; any work may then be perceived and thought as an autonomous entity).This study will enable us to bring to light a basis of the psychic activity : the appraisal of the distance between the fixed and the changing. Baroque Basse continue Bokemeyer (Heinrich) Buxtehude (Dietrich) Cantate Chiffrages Continuo Figures musicales Fixe Héritage Husum Identité Kapellmeiter Luther Luthéranisme Motif générateur Muable Musique allemande Musique luthérienne Musique sacrée Œuvres vocales Organiste Orgue Protestantisme Réduction mélodique Réduction harmonique Ritornello Schleswig-Holstein Sinfonia Baroque Basso continuo Bokemeyer (Heinrich) Buxtehude (Dietrich) Cantate Figuring Continuo Musical figure Fixed Heritage Husum Identity Kapellmeiter Luther Lutheranism Pattern generator Changing German music Lutheran music Sacred music Vocal works Organist Organ Protestantism Melodic reduction Harmonic reduction Ritornello Schleswig-Holstein Sinfonia

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