A pair of studies investigating the deposition and surface chemical properties of ultrathin metal films were pursued: (i) Pt-Co alloys on Mo(110); and (ii) Pd on Pt(111). Experimental measurement was based on a combination of electron spectroscopy (low energy ion scattering spectroscopy, X-ray photoelectron spectroscopy, Auger electron spectroscopy, and low energy electron diffraction) and electrochemistry (voltage efficiency, voltammetry, and coulometry). Mixed-metal preparation of Pt-Co films by thermal vapor deposition (TVD) resulted in a thin-film binary alloy. Careful analysis revealed a substantial divergence between the composition at the interface and that in the interior. This outcome was observed for all compositions and allowed for the construction of a ?surface phase diagram?. The proclivities of the alloys of pre-selected compositions towards enhanced catalysis of the oxygen-reduction reaction were assessed in terms of their voltage efficiencies, as manifested by the open-circuit potential (OCP) in O2-saturated dilute sulfuric acid electrolyte. The particular alloy surface, Pt3Co (XPt=3,XCo=1), whether from the thin film or a bulk single crystal, exhibited the highest OCP, a significant improvement over pure Pt but still appreciably lower than the thermodynamic limit. Under test conditions, the degradation of thusly-prepared films was primarily due to Co corrosion. Ultrathin Pd films on well-defined Pt(111) surfaces, with coverages from 0.5 to 8 monolayers (ML), were prepared by surface-limited redox replacement reaction (galvanic exchange) of underpotentially deposited Cu. Spectroscopic data revealed that films prepared in this manner are elementally pure, pseudomorphic to the substrate, and stable, independent of the surface coverage (?) of palladium. Analysis of the voltammetric profiles in the hydrogen evolution region revealed unique properties of hydrogen adsorption unseen in bulk electrodes. Notably, at 1 ML coverage, a step-free film was produced that did not exhibit hydrogen absorption. At higher coverages, digital (layer-by-layer) deposition gave way to 3D islands in a Stranski- Krastanov growth mode; under these conditions, onset of bulk-like behavior was observed. This method makes possible the synthesis of well-ordered noble-metal films in the absence of high-temperature treatment

From the eighth to the fourteenth century, places of wonder and dread appear in a wide variety of genres in Old and Middle English: epics, lays, romances, saints’ lives, travel narratives, marvel collections, visions of the afterlife. These places appear in narratives of the other world, a term which in Old and Middle English texts refers to the Christian afterlife: Hell, Purgatory, even Paradise can be fraught with wonder, danger, and the possibility of harm. But in addition to the other world, there are places that are not theologically separate from the human world, but that are nevertheless both marvellous and horrifying: the monster-mere in Beowulf, the Faerie kingdom of Sir Orfeo, the demon-ridden Vale Perilous in Mandeville’s Travels, or the fearful landscape of the Green Chapel in Sir Gawain and the Green Knight. Fraught with horror or the possibility of harm, these places are profoundly different from the presented or implied home world of the text. My dissertation investigates how Old and Middle English narratives create places of wonder and dread; how they situate these places metaphysically between the world of living mortals and the world of the afterlife; how they furnish these places with dangerous topography and monstrous inhabitants, as well as with motifs, with tropes, and with thematic concerns that signal their marvellous and fearful nature. I argue that the heart of this poetics of marvellous spaces is displacement. Their wonder and dread comes from boundaries that these places blur and cross, from the resistance of these places to being known or mapped, and from the deliberate distancing between these places and the home of their texts. This overarching concern with displacement encourages the migration of iconographic motifs, tropes, and themes across genre boundaries and theological categories.

No description available.

No description available.

There are two big challenges which restrict the extensive application of fully coupled geomechanics-reservoir modeling. The first challenge is computational effort. Consider a 3-D simulation combining pressure and heat diffusion, elastoplastic mechanical response, and saturation changes; each node has at least 5 degrees of freedom, each leading to a separate equation. Furthermore, regions of large p, T and σ′ gradients require small-scale discretization for accurate solutions, greatly increasing the number of equations. When the rock mass surrounding the reservoir region is included, it is represented by many elements or nodes. These factors mean that accurate analysis of realistic 3-D problems is challenging, and will so remain as we seek to solve larger and larger coupled problems involving nonlinear responses. To overcome the first challenge, the displacement discontinuity method is introduced wherein a large-scale 3-D case is divided into a reservoir region where Δp, ΔT and non-linear effects are critical and analyzed using FEM, and an outside region in which the reservoir is encased where Δp and ΔT effects are inconsequential and the rock may be treated as elastic, analyzed with a 3D displacement discontinuity formulation. This scheme leads to a tremendous reduction in the degrees of freedom, yet allows for reasonably rigorous incorporation of the reactions of the surrounding rock. The second challenge arises from some forms of numerical instability. There are actually two types of sharp gradients implied in the transient advection-diffusion problem: one is caused by the high Peclet numbers, the other by the sharp gradient which appears during the small time steps due to the transient solution. The way to eliminate the spurious oscillations is different when the sharp gradients are induced by the transient evolution than when they are produced by the advective terms, and existing literature focuses mainly on eliminating the spurious spatial temperature oscillations caused by advection-dominated flow. To overcome the second challenge, numerical instability sources are addressed by introducing a new stabilized finite element method, the subgrid scale/gradient subgrid scale (SGS/GSGS) method.

Constructed in 1886 by Mr. John Abell, the former engine and machine works factory at 48 Abell Street is located near Queen and Dufferin Streets in Toronto, Ontario. This 100,000 square foot heavy timber and red brick building has housed approximately 80 live/work studios since the 1980’s. Recently, rapid gentrification and intensive development proposals in the West Queen West neighbourhood have threatened its existence as an authentic artistic incubator. In a series of chronicles, this thesis documents the history of John Abell and the neighbourhood surrounding his former factory from the late 19th century to present day. Woven into this narrative are the author’s own stories of living in a loft at 48 Abell Street, observing the transformation of the neighbourhood and responding to potential eviction from her home. When the community rallies to the building’s defense, 48 Abell becomes the central figure in a battle over land development with the City and real estate developers in which the key issue is the cultural value of heritage buildings and protection of live/work spaces. Research in the form of mapping and data collection shows the concentration of the arts in the area known as the Queen West Triangle has been a catalyst for gentrification. The resulting displacement of arts production space and low-income residents due to escalating land values is an unintended and sobering reality challenging the current orthodoxy of ‘creative city’ movements in North America.

There are two big challenges which restrict the extensive application of fully coupled geomechanics-reservoir modeling. The first challenge is computational effort. Consider a 3-D simulation combining pressure and heat diffusion, elastoplastic mechanical response, and saturation changes; each node has at least 5 degrees of freedom, each leading to a separate equation. Furthermore, regions of large p, T and σ′ gradients require small-scale discretization for accurate solutions, greatly increasing the number of equations. When the rock mass surrounding the reservoir region is included, it is represented by many elements or nodes. These factors mean that accurate analysis of realistic 3-D problems is challenging, and will so remain as we seek to solve larger and larger coupled problems involving nonlinear responses. To overcome the first challenge, the displacement discontinuity method is introduced wherein a large-scale 3-D case is divided into a reservoir region where Δp, ΔT and non-linear effects are critical and analyzed using FEM, and an outside region in which the reservoir is encased where Δp and ΔT effects are inconsequential and the rock may be treated as elastic, analyzed with a 3D displacement discontinuity formulation. This scheme leads to a tremendous reduction in the degrees of freedom, yet allows for reasonably rigorous incorporation of the reactions of the surrounding rock. The second challenge arises from some forms of numerical instability. There are actually two types of sharp gradients implied in the transient advection-diffusion problem: one is caused by the high Peclet numbers, the other by the sharp gradient which appears during the small time steps due to the transient solution. The way to eliminate the spurious oscillations is different when the sharp gradients are induced by the transient evolution than when they are produced by the advective terms, and existing literature focuses mainly on eliminating the spurious spatial temperature oscillations caused by advection-dominated flow. To overcome the second challenge, numerical instability sources are addressed by introducing a new stabilized finite element method, the subgrid scale/gradient subgrid scale (SGS/GSGS) method.

Constructed in 1886 by Mr. John Abell, the former engine and machine works factory at 48 Abell Street is located near Queen and Dufferin Streets in Toronto, Ontario. This 100,000 square foot heavy timber and red brick building has housed approximately 80 live/work studios since the 1980’s. Recently, rapid gentrification and intensive development proposals in the West Queen West neighbourhood have threatened its existence as an authentic artistic incubator. In a series of chronicles, this thesis documents the history of John Abell and the neighbourhood surrounding his former factory from the late 19th century to present day. Woven into this narrative are the author’s own stories of living in a loft at 48 Abell Street, observing the transformation of the neighbourhood and responding to potential eviction from her home. When the community rallies to the building’s defense, 48 Abell becomes the central figure in a battle over land development with the City and real estate developers in which the key issue is the cultural value of heritage buildings and protection of live/work spaces. Research in the form of mapping and data collection shows the concentration of the arts in the area known as the Queen West Triangle has been a catalyst for gentrification. The resulting displacement of arts production space and low-income residents due to escalating land values is an unintended and sobering reality challenging the current orthodoxy of ‘creative city’ movements in North America.

An electrostatic actuator driven by conventional voltage control and charge control requires high actuation voltage and suffers from the pull-in phenomenon that limits its operation range, much less than its entire gap. To provide effective solutions to these problems, we present complete analytical and numerical models of various electrostatic actuators coupled with resonant drive circuits that are able to drive electrostatic actuators at much lower input voltage than that of conventional actuation methods and to extend their operation range beyond their conventional pull-in points in the presence of high parasitic capacitance. Moreover, in order to validate the analytical and numerical models of various electrostatic actuators coupled with the resonant drive circuits, we perform the experiment on the microplate and the micromirror coupled with the resonant drive circuit. For instance, using a high voltage amplifier, we manage to rotate the micromirror with sidewall electrodes by 6 ° at 180 V. However, using the resonant drive circuit, we are able to rotate the same micromirror by 6 ° at much lower input voltage, 8.5 V. In addition, the presented work also facilitates the stability analysis of electrostatic actuators coupled with the resonant drive circuits and provides how the effect of the parasitic capacitance can be minimized. For example, the resonant drive circuit placed within a positive feedback loop of a variable gain amplifier is able to extend the operation range much further even in the presence of very high parasitic capacitance. The resonant drive circuit with the proposed feedback controllers is also able to minimize the detrimental effects of the parasitic capacitance and to displace a parallel-plate actuator over its entire gap without the saddle-node bifurcation. Finally, we present a new displacement measurement method of electrostatic actuators coupled with the resonant drive circuits by sensing the phase delay of an actuation voltage with respect to an input voltage. This new measurement method allows us to easily implement feedback control into existent systems employing an electrostatic actuator without any modification or alteration to the electrostatic actuator itself. Hence, this research work presents the feasibility of electrostatic actuators coupled with the resonant drive circuit in various industrial and medical applications, in which the advantages of miniaturization, low supply voltage, and low power consumption are greatly appreciated.

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