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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.
51

Animism in Whitman: "Multitudes" of Interpretations?

Woodbury, Rachelle Helene 07 July 2006 (has links) (PDF)
Walt Whitman used animistic techniques in his poetry and prose, specifically "Song of the Redwood Tree," "Out of the Cradle Endlessly Rocking," and Specimen Days. The term animism can be traced to the Latin root of the word, anime, which connotes a "soul" or "vitality." So, when one is talking about animistic techniques, one is speaking of the (metaphoric or realistic) ensoulment of natural objects. In the wake of a growing global crisis modern scholarship has begun reexamining the implications of this belief; often it introduces ambiguities into an otherwise comfortable relationship of unquestioned human domination. In Specimen Days, Whitman seems to have a more clear view of his natural philosophy, in which he expresses his belief that nature possesses an inherency that he envies and an ability to communicate that quality with him. However, Whitman's "Song of the Redwood Tree" is ambiguous and contradicting. Whitman creates a vision of Manifest Destiny by portraying settlers in California clearing space for houses and agriculture by cutting down the majestic redwood forests. However, this poem contains a particularly odd element: the trees have a voice. They mourn their own demise while simultaneously celebrating the arrival of the new American populace. It is a conflicting image. The animistic, majestic qualities of the trees challenge an anthropocentric view of the world, not allowing the reader to quickly disregard the extinction of the redwood forests in order to embrace American ideals of progress, which in a way defeats the more imperialistic message of the poem. Another comparison, with "Out of the Cradle Endlessly Rocking," demonstrates how important subversion of self to place is when using animistic techniques in poetry. This poem implies that animate nature is a locus for Whitman's creative genius, both inspiring his poetry and permeating it with confusion. Whitman's very engagement with the process of imagining a voice for nature inserts doubt into some of his more imperialistic pronouncements and encourages the reader to question his own previously unexamined assumptions. Animistic literary techniques have the potential to encourage an involvement with non-human nature, along with a more conscious awareness of the way we use (and abuse) that Other.
52

Effets d’un lit berceur sur la qualité du sommeil chez des jeunes adultes bons dormeurs durant plusieurs nuits consécutives

Fontaine, Ophélia 08 1900 (has links)
Contexte : Le traitement des informations externes étant toujours présent pendant le sommeil, présenter des stimulations sensorielles durant le sommeil peut en améliorer la qualité. Le mouvement latéral et doux d’un lit berçant, a montré des résultats prometteurs chez l’humain et la souris, sur une seule nuit chez des bons dormeurs. Objectif : L’objectif de ce projet pilote est d’évaluer les effets préliminaires du bercement durant le sommeil (mouvement latéral, 0.25Hz) sur la qualité du sommeil pendant plusieurs nuits consécutives. Nous cherchons à tester notre lit berceur et à reproduire les effets bénéfiques trouvés dans la littérature sur la qualité du sommeil, et à déterminer si ses effets se maintiennent lors de plusieurs nuits. Méthodologies : Le sommeil de 8 jeunes bons dormeurs (24.25  3.20 ans), a été évalué objectivement (polysomnographie, PSG), et subjectivement (questionnaires) durant 6 nuits, dont 5 nuits expérimentales sur le lit berceur (3 nuits bercées (B), 2 nuits stationnaires (S)). Résultats : Lors de B1, les participants ont passé moins de temps en sommeil profond (N3; p=0.013), et plus de temps éveillé (p=0.03) que lors de S1. En B2 ils ont passé plus de temps éveillé qu’en S2 (p=0.039), moins en B2 qu’en B1 (p=0.023), sans changements entre S1 et S2 ni entre B2 et B3 (toutes p>0.05), bien que 6/8 participants ont augmenté leur %N3 et diminué leur %N1+N2 de B2 à B3. Aucune influence du bercement sur la qualité du sommeil subjective, l’humeur ou la perception du sommeil n’est ressortie (toutes p>0.05). Conclusion : Au cours des 3 nuits bercées, une habituation du dormeur au bercement semble se produire. L’absence de résultats bénéfiques viendrait des propriétés de l’accélération linéaire du moteur. / Context: Since the process of external information continues during sleep, presenting sensory stimuli during sleep can enhance its quality. The gentle lateral movement of a rocking bed has shown promising results in humans and mice during a single night with good sleepers. Objective: The objective of this pilot study is to evaluate the preliminary effects of rocking during sleep (lateral movement, 0.25Hz) on sleep quality over multiple consecutive nights. We aim to test our rocking bed and replicate the beneficial effects found in the literature on sleep quality, as well as determine if these effects persist over several nights. Methodology: The sleep of 8 young good sleepers (24.25 ± 3.20 years) was objectively assessed (polysomnography, PSG) and subjectively evaluated (questionnaires) over 6 nights, including 5 experimental nights on the rocking bed (3 rocking nights (B), 2 stationary nights (S)). Results: During B1, participants spent less time in deep sleep (N3; p=0.013) and more time awake (p=0.03) compared to S1. They spent more time awake in B2 than in S2 (p=0.039), and in B2 than in B1 (p=0.023), with no changes between S1 and S2 nor between B2 and B3 (all p>0.05). However, 6/8 participants increased their %N3 and decreased their %N1+N2 from B2 to B3. No influence of rocking on subjective sleep quality, mood, or sleep perception was observed (all p>0.05). Conclusion: Over the course of the 3 rocking nights, a habituation of the participant to the rocking movement seems to occur. The absence of beneficial results may be attributed to the linear acceleration properties of the motor.
53

Ties That Bind

Orlowski, Jessica Marie 23 March 2010 (has links)
I am fascinated by the inner thoughts, the memories, and the cumulative experience that make us each a complex physiological puzzle. From birth, sociological building blocks are constructed forming emotional walls and unexpected doorways, boundaries and comfortable passageways through the architecture of our personalities. My thesis work, which is comprised of ceramic figures and interactive toys, offers playful memory triggers and evocative spaces in which viewers can deconstruct the building blocks of their social persona.
54

Caractérisation des défauts cristallins au MEB par canalisation d’électrons assistée par diagrammes pseudo-Kikuchi haute résolution : application à l’acier IF, UO2 et TiAl / Characterization of crystallographic defects in SEM by electron channeling assisted by high resolution pseudo-Kikuchi patterns : application to IF-steel, UO2 and TiAl

Mansour, Haithem 08 December 2016 (has links)
La technique Imagerie par Contraste de Canalisation d'Electron (ECCI) est utilisée en microscopie électronique à balayage (MEB) pour visualiser et caractériser des défauts cristallins tels que les dislocations. L’ECCI nécessite l'orientation, avec grande précision (meilleure que 0,1°), du cristal à analyser par rapport au faisceau d’électrons pour satisfaire les conditions très strictes de canalisation d'électrons. À cause de la limitation en résolution spatiale et angulaire des techniques actuelles permettant de déterminer l’orientation cristallographique, la caractérisation des défauts cristallins par ECCI est actuellement appliquée à des monocristaux (ou des polycristaux possédant des gros grains) et les conditions de canalisation ne sont pas toujours satisfaites. Dans ce projet de thèse, un mode de balayage Précession de faisceau (Rocking Beam en anglais) a été développé dans un microscope électronique à balayage. Il permet l’acquisition de diagrammes pseudo-Kikuchi haute résolution spatiale (500nm) et angulaire (0,04°) (High Resolution Selected Area Channeling Pattern en anglais (HR-SACP)) et de contrôler les conditions de canalisations nécessaire à l’ECCI. Ceci a permis d’améliorer considérablement la précision de l’ECCI (Accurate ECCI A-ECCI) et d’élargir son domaine d’application aux matériaux polycristallins à grains fins. Dans un deuxième temps, l’A-ECCI assistée par HR-SACP a été utilisé pour caractériser des défauts cristallins (dislocations, sous joint de grain, domaine d’ordre) dans des matériaux massifs polycristallins (Acier IF, UO2, TiAl). Des procédures similaires à celles utilisées dans la microscopie électronique en transmission (MET) sont alors appliquées en s’affranchissant de la préparation fastidieuse de lames minces et en profitant des autres avantages du MEB / Electron Channeling Contrast Imaging (ECCI) is a Scanning Electron Microscope (SEM) technique used to observe and characterize crystallographic defects. ECCI requires the crystal to be oriented relative to the electron beam with high accuracy (0.1°) in order to control the electron channeling conditions. The SEM techniques used to determine the crystallographic orientation, such as conventional Electron BackScattered Diffraction (EBSD) or Rocking Beam, don’t satisfy the high accuracy required for ECCI. Therefore, the characterization of crystallographic defects by ECCI is used only in single crystals or polycristals with large grains and channeling conditions are not always satisfied. In this thesis, a development of a new Rocking Beam mode in SEM is presented. It allows the collection of High spatial (500nm) and angular (0.04°) Resolution Selected Area Channeling Pattern (HR-SACP) and the control of channeling conditions required for ECCI with high accuracy (Accurate ECCI A-ECCI). In a second phase of this thesis, A-ECCI assisted by HR-SACP is used to characterize crystallographic defects like dislocation, sub-grains and order domains in fine grained bulk materials (IF-Steel, UO2, TiAl). In order to achieve this, several procedures (invisibility criteria) normally used in Transmission Electron Microscopy are applied. Using A-ECCI in SEM has many advantages over TEM such as the possibility of analyzing large areas and the relative easiness in sample preparation
55

Seismic isolation of nuclear reactor vessels considering soil-structure interaction

Samyog Shrestha (13149003) 26 July 2022 (has links)
<p>The research presented in this dissertation investigates the influence of soil-structure<br> interaction on seismic isolation of nuclear reactor vessels using numerical simulations. This<br> research is motivated by the nuclear industry searching for viable solutions to standardize<br> the design of reactor vessels. Seismic isolation of reactor vessels is a potential solution as it<br> enables deployment of standardized reactor vessels irrespective of site seismic hazard<br> thereby saving time and cost by allowing large-scale factory fabrication of standard<br> modules and by eliminating the need for repeated approval of reactor vessel design. Seismic<br> isolation is also a technology that has matured from successful implementation in buildings<br> and bridges allowing easier transition to nuclear applications. Currently, the<br> implementation of component-level seismic isolation in nuclear industry is challenging due<br> to gaps in research and lack of specific guidelines.</p> <p><br></p> <p><br> In this research, the effectiveness and potential limitations of using conventional friction<br> pendulum bearings for component-level isolation are investigated based on conceptual<br> numerical models of seismically isolated reactor vessels at different nuclear power plant<br> sites subject to a variety of ground motions. The numerical modeling and analysis<br> approach presented in this research are checked using experimental data and results from<br> multiple numerical codes to ensure reliability of the obtained analysis results.</p> <p><br></p> <p><br> Within the scope of this study, it is found that slender vessels are particularly vulnerable<br> to rotational acceleration at the isolation interface. Rotational acceleration at the isolation<br> interface is caused by rotation at the foundation level of the containment building housing<br> the isolated reactor vessel and by excitation of higher horizontal translational modes of the<br> seismically isolated system. Rotation of the building foundation increases with decrease in<br> shear wave velocity of the soil surrounding the building foundation. When the containment<br> building is embedded below the soil surface, the effect of embedment on peak horizontal<br> acceleration of the isolated vessel depends on the amount of increase in shear wave velocity<br> at the foundation level of the building. When embedment does not result in any change in<br> shear wave velocity, it is found to have negligible impact on the acceleration response of the<br> isolated vessel.</p> <p><br></p> <p>  The optimum location to support a vessel for seismic isolation is found to be on a plane<br> passing through its center of mass. It minimizes horizontal acceleration in the isolated<br> vessel as well as the tendency of isolator to uplift. Isolator uplift and exceedence of<br> displacement capacity of the isolator during extreme events are possible drawbacks in using<br> seismic isolation technology since they produce impact forces due to uplift and<br> re-engagement of the isolator or due to collision between the isolated system and the moat<br> wall. If such cases are avoided, seismic isolation of reactor vessel could provide more than<br> 50% reduction in peak acceleration of vessel except for low-intensity motions that do not<br> engage the isolator.<br>  <br>  </p>
56

Ultimate Limit States in Controlled Rocking Steel Braced Frames

Steele, Taylor Cameron January 2019 (has links)
The Insurance Bureau of Canada released a report in 2013 that evaluated the seismic risk of two major metropolitan areas of Canada, with projected losses of $75bn in British Columbia along the Cascadia subduction zone, and $63bn in the east through the Ottawa-Montreal-Quebec corridor. Such reports should prompt researchers and designers alike to rethink the way that seismic design is approached in Canada to develop resilient and sustainable cities for the future. To mitigate the economic losses associated with earthquake damage to buildings in seismically active areas, controlled rocking steel braced frames have been developed as a seismically resilient low-damage lateral-force resisting system. Controlled rocking steel braced frames (CRSBFs) mitigate structural damage during earthquakes through a controlled rocking mechanism, where energy dissipation can be provided at the base of the frame, and pre-stressed tendons pull the frame back to its centred position after rocking. The result is a building for which the residual drifts of the system after an earthquake are essentially zero, and the energy dissipation does not result from structural damage. Design methods for the base rocking joint and the capacity-protected frame members in CRSBFs have been proposed and validated both numerically and experimentally. However, the is no consensus on how to approach the design of the frame members, questions remain regarding how best to design CRSBFs to prevent building collapse, and no experimental work has been done regarding how to connect the CRSBF to the rest of the structure to accommodate the rocking motion. Because the force limiting mechanism of a CRSBF is rocking only at the base of the frame, the frame member forces are greatly influenced by the higher-mode response, resulting in more complex methods to design the frame members. This thesis begins by outlining two new design procedures for the frame members in controlled rocking steel braced frames that target both simplicity and accuracy. The first is a dynamic procedure that requires a truncated response spectrum analysis on a model of the frame with modified boundary conditions to consider the rocking behaviour. The second is an equivalent static procedure that does not require any modifications to the elastic frame model, instead using theory-based lateral force distributions to consider the higher modes of the rocking structure. Neither method requires empirical calibration to estimate the forces at the target intensity. The base rocking joint design is generally in good agreement between the various research programs pioneering the development of the CRSBFs. However, the numerous parameters available to select during the design of the base rocking joint give designers an exceptional amount of control over the performance of the system, and little research is available on how best to select these parameters to target or minimise the probability of collapse for the building. This thesis presents a detailed numerical model to capture collapse of buildings with CRSBFs as their primary lateral force resisting system and uses this model to generate collapse fragility curves for different base rocking joint design parameters. The parameters include the response modification factor, the hysteretic energy dissipation ratio, and the post-tensioning prestress ratio. This work demonstrates that CRSBFs are resilient against collapse, as designing the base rocking joint with response modification factors as large as 30, designing the post-tensioning to prevent yielding at moderate seismic hazard levels, and using zero energy dissipation could lead to designs with acceptable margins of safety against collapse. While the design procedures are shown to be accurate for estimating the frame member force demand for the targeted intensity level, there is still a high level of uncertainty around what intensity of earthquake a building will experience during its lifespan, and there is no consensus on what intensity should be targeted for design. To address this, the ability of the capacity design procedures to provide a sufficiently low probability of collapse due to excessive frame member buckling and yielding is evaluated and compared to the probability that the building will collapse due to excessive rocking of the frame. The results of the research presented here suggest that the probability of collapse due to either frame member failure or excessive rocking should be evaluated separately, and that targeting the intensity with a 10% probability of exceedance in 50 years is sufficient for the design of the frame members. Finally, critical to the implementation of CRSBFs in practice is how they may be connected to the rest of the structure to accommodate the uplifting of the CRSBF while rocking under large lateral forces. An experimental program was undertaken to test three proposed connection details to accommodate the relative uplifts and forces. The connections that accommodate the uplifts through sliding performed better than that which accommodated the uplifts though material yielding, but the best way to transfer the forces and accommodate the uplifting without influencing the overall behaviour of the system is to position the connection such that it does not need to undergo large uplifts and carry lateral force simultaneously. A detailed numerical model of the experimental setup is presented and is shown to simulate the important response quantities for each of the tested connections. Using the results of this work, designers worldwide will be confident to design CRSBFs for structures from the base rocking joint to the selection of floor-to-frame connections for a complete system design while ensuring a safe and resilient building structure for public use and well-being. / Thesis / Doctor of Philosophy (PhD) / Traditional approaches to seismic design of buildings have generally been successful at preventing collapse and protecting the lives of the occupants. However, the buildings are often left severely damaged, often beyond repair. To address these concerns, controlled rocking steel braced frames have been proposed as part of a new construction technique to mitigate or prevent damage to steel buildings during earthquakes, but several aspects of the design and overall safety have yet to be explored or demonstrated. This thesis proposes and validates new tools to design controlled rocking steel braced frames and provides recommendations on how best to design them to achieve a safe probability against collapse. Details are proposed and presented for components to connect the controlled rocking steel braced frames into the rest of the structure. The findings of this thesis will aid practitioners looking to deliver resilient and sustainable structural designs for buildings in our cities of the future.

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