The purpose of this thesis is to evaluate the seismic response of the UC Physics Building based on recorded ground motions during the Canterbury earthquakes, and to use the recorded response to evaluate the efficacy of various conventional structural analysis modelling assumptions. The recorded instrument data is examined and analysed to determine how the UC Physics Building performed during the earthquake-induced ground motions. Ten of the largest earthquake events from the 2010-11 Canterbury earthquake sequence are selected in order to understand the seismic response under various levels of demand. Peak response amplitude values are found which characterise the demand from each event. Spectral analysis techniques are utilised to find the natural periods of the structure in each orthogonal direction. Significant torsional and rocking responses are also identified from the recorded ground motions. In addition, the observed building response is used to scrutinise the adequacy of NZ design code prescriptions for fundamental period, response spectra, floor acceleration and effective member stiffness. The efficacy of conventional numerical modelling assumptions for representing the UC Physics Building are examined using the observed building response. The numerical models comprise of the following: a one dimensional multi degree of freedom model, a two dimensional model along each axis of the building and a three dimensional model. Both moderate and strong ground motion records are used to examine the response and subsequently clarify the importance of linear and non-linear responses and the inclusion of base flexibility. The effects of soil-structure interaction are found to be significant in the transverse direction but not the longitudinal direction. Non-linear models predict minor in-elastic behaviour in both directions during the 4 September 2010 Mw 7.1 Darfield earthquake. The observed torsional response is found to be accurately captured by the three dimensional model by considering the interaction between the UC Physics Building and the adjacent structure. With the inclusion of adequate numerical modelling assumptions, the structural response is able to be predicted to within 10% for the majority of the earthquake events considered.

A fundus camera a complex optical system that makes use of the principle of reflex free indirect ophthalmoscopy to image the retina. Despite being in existence as early as 1900's, little has changed in the design of a fundus camera and there is minimal information about the design principles utilized. Parameters and specifications involved in the design of fundus camera are determined and their affect on system performance are discussed. Fundus cameras incorporating different design methods are modeled and a performance evaluation based on design parameters is used to determine the effectiveness of each design strategy. By determining the design principles involved in the fundus camera, new cameras can be designed to include specific imaging modalities such as optical coherence tomography, imaging spectroscopy and imaging polarimetry to gather additional information about properties and structure of the retina. Design principles utilized to incorporate such modalities into fundus camera systems are discussed. Design, implementation and testing of a snapshot polarimeter fundus camera are demonstrated.

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / There are many applications for High-speed photography, and most rely on film as the primary medium of data acquisition. One such application of interest to the military services is the study of stores separation from aircraft. This type of testing has traditionally used high-speed film to gather data, however, there are many disadvantages to using film, such as the high cost of raw film, as well as the high processing expense after it has been exposed. In addition, there is no way to review data from film until it has been processed, nor is there any way to preview in real-time other conditions such as lighting which may affect the outcome of a test event. This paper discusses the characteristics of television systems with respect to motion picture systems, the challenges of recording and transmitting pictures, as well as the nature of what the first and eventual desired systems might be.

International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / The MicroDAS-1000 is an airborne Data Acquisition System (DAS) designed to meet the growing needs of airframe manufacturers for extensive test data accumulation, processing and evaluation. As such, the system has been designed with emphasis on modularity, miniaturization and ease of operator usage and expansion. The MicroDAS product line includes a series of components used as building blocks to configure systems of virtually any size. The modular design of these components allows considerable latitude to the instrumentation engineer in configuring systems for simple or complex applications. The modular concept has been extended to the design of plug-in modules for different functional requirements and system applications. All units are under software control to allow rapid reconfiguration and setup as requirements for instrumentation and data gathering change.

Using the Gemini Planet Imager located at Gemini South, we measured the near-infrared (1.0-2.4 mu m) spectrum of the planetary companion to the nearby, young star beta. Pictoris. We compare the spectrum obtained with currently published model grids and with known substellar objects and present the best matching models as well as the best matching observed objects. Comparing the empirical measurement of the bolometric luminosity to evolutionary models, we find a mass of 12.9. +/- 0.2. M-Jup, an effective temperature of 1724. +/- 15 K, a radius of 1.46. +/- 0.01. R-Jup, and a surface gravity of log g = 4.18. 0.01 [dex] (cgs). The stated uncertainties are statistical errors only, and do not incorporate any uncertainty on the evolutionary models. Using atmospheric models, we find an effective temperature of 1700-1800 K and a surface gravity of log g = 3.5-4.0 [dex] depending upon the model. These values agree well with other publications and with "hot-start" predictions from planetary evolution models. Further, we find that the spectrum of beta Pic. b best matches a low surface gravity L2. +/- 1 brown dwarf. Finally, comparing the spectrum to field brown dwarfs, we find the the spectrum best matches 2MASS J04062677- 381210 and 2MASS J03552337 + 1133437.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Direct detection and spectroscopy of exoplanets requires high-contrast imaging. For habitable exoplanets in particular, located at a small angular separation from the host star, it is crucial to employ small inner working angle (IWA) coronagraphs that efficiently suppress starlight. These coronagraphs, in turn, require careful control of the wavefront that directly impacts their performance. For ground-based telescopes, atmospheric refraction is also an important factor, since it results in a smearing of the point-spread function (PSF), that can no longer be efficiently suppressed by the coronagraph. Traditionally, atmospheric refraction is compensated for by an atmospheric dispersion compensator (ADC). ADC control relies on an a priori model of the atmosphere whose parameters are solely based on the pointing of the telescope, which can result in imperfect compensation. For a high-contrast instrument like the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system, which employs very small IWA coronagraphs, refraction-induced smearing of the PSF has to be less than 1 mas in the science band for optimum performance. In this paper, we present the first on-sky measurement and correction of residual atmospheric dispersion. Atmospheric dispersion is measured from the science image directly, using an adaptive grid of artificially introduced speckles as a diagnostic to feedback to the telescope's ADC. With our current setup, we were able to reduce the initial residual atmospheric dispersion from 18.8 mas to 4.2 in broadband light (y- to H-band) and to 1.4 mas in the H-band only. This work is particularly relevant to the upcoming extremely large telescopes (ELTs) that will require fine control of their ADC to reach their full high-contrast imaging potential.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

The aim of this study was to compare the incidence of root canal dentinal micro-cracks after canal instrumentation using reciprocating files (WaveOne Gold® and Twisted Adaptive®) and continuous rotation files (Edge Evolve® and EndoSequence®) in an ex-vivo benchtop study. This project used a novel methodology of finding dentinal defects using the “K-cube”, which allows evaluators to visualize sectioned root surfaces before instrumentation and after instrumentation. Mesial roots from 40 human mandibular first molars were divided into 4 groups of 10 for each file type. Root section pictures were taken with a Zeiss Discovery V20 stereomicroscope before and after canal instrumentation. Each of the pre-instrumentation and post-instrumentation images were evaluated for dentinal defects by four calibrated endodontists utilizing REDCap survey. Using a chi-square analysis, there was no statistically significant difference between dentinal defects created by continuous and reciprocating rotation (p=0.1924) and no difference between the four file types (p=0.2317).

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.