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No / In this work we present the angle of arrival estimation techniques and their comparison at different values of SNR using a 5 element UCA. The techniques that have been considered include phase interferometry, Multiple Signal Classification and covariance. The results show that for very low values of SNR the performance of the covariance matrix based algorithm is the best but for slightly higher values of SNR, MUSIC algorithm outperforms covariance.

An experimental investigation was conducted in a static ground test facility to determine the flow quality of a serpentine inlet duct incorporating active flow control for several simulated flight conditions. The total pressure distortion at the aerodynamic interface plane (AIP) was then used to predict the resulting stability for a compression system. This study was conducted using a model of a compact, low observable, engine inlet duct developed by Lockheed Martin. A flow control technique using air injection through microjets at 1% of the inlet mass flow rate was developed by Lockheed Martin to improve the quality of the flow exiting the inlet duct. Both the inlet duct and the flow control technique were examined at cruise condition and off-design simulated flight conditions (angle of attack and asymmetric distortion). All of the experimental tests were run at an inlet throat Mach number of 0.55 and a resulting Reynolds number of 1.76*105 based on the hydraulic diameter at the inlet throat. For each of the flight conditions tested, the flow control scheme was found to improve the flow uniformity and reduce the inlet distortion at the AIP. For simulated cruise condition, the total pressure recovery was improved by ~2% with the addition of flow control. For the off-design conditions of angle of attack and asymmetric distortion, the total pressure recovery was improved by 1.5% and 2% respectively. All flight conditions tested showed a reduction in circumferential distortion intensity with flow control. The cruise condition case showed reduced maximum circumferential distortion of 70% with the addition of flow control. A reduction in maximum circumferential distortion of 40% occurred for the angle of attack case with flow control, and 30% for the asymmetric distortion case with flow control. The inlet total pressure distortion was used to predict the changes in stability margin of a compression system due to design and off-design flight conditions and the improvement of the stability margin with the addition of flow control. A parallel compressor model (DYNTECC) was utilized to predict changes in the stability margin of a representative compression system (NASA Stage 35). Without flow control, all three cases show similar reduced stability margins on the order of 30% of the original stability margin for NASA Stage 35 at 70% corrected rotor speed. With the addition of flow control, the cruise condition tested improved the stability margin to 80% of the original value while the off-design conditions recover to 60% of the original margin. Overall, the flow control has been found to be extremely beneficial in improving the operating range of a compression system for the same inlet duct without flow control. / Ph. D.

Le glaucome est un groupe hétérogène de maladies qui sont caractérisées par l'apoptose des cellules ganglionnaires de la rétine et la dégénérescence progressive du nerf optique. Il s’agit de la première cause de cécité irréversible, qui touche environ 60 millions de personnes dans le monde. Sa forme la plus commune est le glaucome à angle ouvert (GAO), un trouble polygénique causé principalement par une prédisposition génétique, en interaction avec d'autres facteurs de risque tels que l'âge et la pression intraoculaire élevée (PIO). Le GAO est une maladie génétique complexe, bien que certaines formes sévères sont autosomiques dominantes. Dix-sept loci ont été liés à la maladie et acceptés par la « Human Genome Organisation » (HUGO) et cinq gènes ont été identifiés à ces loci (MYOC, OPTN, WDR36, NTF4, ASB10). Récemment, des études d’association sur l’ensemble du génome ont identifié plus de 20 facteurs de risque fréquents, avec des effets relativement faibles. Depuis plus de 50 ans, notre équipe étudie 749 membres de la grande famille canadienne-française CA où la mutation MYOCK423E cause une forme autosomale dominante de GAO dont l’âge de début est fortement variable. Premièrement, il a été montré que cette variabilité de l’âge de début de l'hypertension intraoculaire possède une importante composante génétique causée par au moins un gène modificateur. Ce modificateur interagit avec la mutation primaire et altère la sévérité du glaucome chez les porteurs de MYOCK423E. Un gène modificateur candidat WDR36 a été génotypé dans 2 grandes familles CA et BV. Les porteurs de variations non-synonymes de WDR36 ainsi que de MYOCK423E de la famille CA ont montré une tendance à développer la maladie plus jeune. Un outil de forage de données a été développé pour représenter des informations connues relatives à la maladie et faciliter la priorisation des gènes candidats. Cet outil a été appliqué avec succès à la dépression bipolaire et au glaucome. La suite du projet consiste à finaliser un balayage de génome sur la famille CA et à séquencer les loci afin d’identifier les variations modificatrices du glaucome. Éventuellement, ces variations permettront d’identifier les individus dont le glaucome risque d’être plus agressif. / Glaucoma, which is a group of ocular disorders, is characterized by optic nerve atrophy following progressive loss of retinal ganglion cells. It is the leading cause of blindness worldwide which is affecting an estimated 60 million people worldwide. Open angle glaucoma (OAG), the common form of glaucoma, is a polygenic disorder caused mainly by genetic predisposition, in interaction with other risk factors such as age and elevated intraocular pressure (IOP). OAG is a complex genetic disease, although some severe forms are simply autosomal dominant. Seventeen loci were shown to be associated with the disease and are reported by the «Human Genome Organisation» HUGO and five genes have been identified in those loci (MYOC, OPTN, WDR36, NTF4, ASB10). Recently, genome-wide association studies have found more than 20 frequent risk factors with relatively small effects. For more than 50 years, our team have been studying the CA family, a large French-Canadian pedigree (749 people), in which autosomal OAG is caused by the MYOCK423E mutation which is characterised by variable age at onset. It has been demonstrated that the variability of the age at beginning of ocular hypertension has an important genetic component caused by at least one modifier gene. A potential modifier gene, WDR36, has been genotyped in families CA and BV. In the CA family, carriers of non-synonymous WDR36 variations which are also carriers of MYOCK423E, have shown a tendency to develop the disease younger. This modifier interacts with the primary mutation and alters the severity of glaucoma for MYOCK423E mutation carriers. A data-mining tool has been developed to generate graphical diagram of a disease causal model and facilitate the prioritization of the candidate genes. It has been successfully used for bipolar disorder and glaucoma. The next step for this project is to finalize a genome scan of the CA family and to sequence loci with the goal of identifying glaucoma modifier variations. Those variations could potentially allow identification of the individuals for whom glaucoma could be far more aggressive.

In the basic understanding of measurement, students are expected to be able to subdivide a given whole into a unit and then change the position of that unit along the entire length of the whole. These basic operations of subdivision and change of position are related to the more formal operations of partitioning and iterating. In the context of fractions, partitioning and iterating play a fundamental role in understanding fractions as measures, where students are expected to partition a whole into an iterable unit. In the context of angle measurement, students are expected to measure angles as a fractional amount of a full rotation or a circle, by partitioning the circle into a unit angle and then iterating that unit angle to find the measure of the given angle. Despite this link between measurement, fractions, and angles, research suggests that there is a disconnect between students' concepts of measurement and geometry concepts, including angle and angle measurement. Therefore, one area of study that might help us understand this disconnection would be to investigate the relationship between students' concepts of measurement and their concepts of angle measurement. This current study documents sixth, seventh, and eighth grade students' measurement schemes for fractions and their quantifications of angularity, and then investigates the relationship between them. This research is guided by the following question: What is the relationship between middle school students' measurement schemes for fractions and their quantifications of angularity? Results indicate that the majority of students involved in this study do not possess a measurement concept of fractions nor a measurement concept of angularity. However, these results demonstrate that there is a relationship between students' measurement schemes for fractions and their quantifications of angularity. It is concluded that students who construct more sophisticated fraction schemes tend to construct more sophisticated quantifications of angularity. / Doctor of Philosophy / Although the concepts of measurement, fractions, and angle measurement are related, research suggests that there is a disconnect between students' concepts of measurement and geometry concepts, including angle and angle measurement. Therefore, one area of study that might help us understand this disconnection would be to investigate the relationship between students' concepts of measurement and their concepts of angle measurement. This current study documents sixth, seventh, and eighth grade students' understandings of measurement, as indicated by their fraction schemes, and angle measurement, as indicated by how they quantify angularity or the openness of an angle. This study then investigates the relationship between them. This research is guided by the following question: What is the relationship between middle school students' measurement schemes for fractions and their quantifications of angularity? Results indicate that the majority of students involved in this study do not possess a measurement concept of fractions nor a measurement concept of angularity. However, these results demonstrate that there is a relationship between students' measurement schemes for fractions and their quantifications of angularity. It is concluded that students who construct more sophisticated fraction schemes tend to construct more sophisticated quantifications of angularity.

La population québécoise (~7 millions d’habitants) est constituée d'environ six millions d'individus descendant d'un bassin génétique estimé à 8500 fondateurs. Les caractéristiques uniques de cette population facilitent beaucoup les recherches en génétique. Cette thèse de doctorat traite de la génétique moléculaire du glaucome, une maladie oculaire insidieuse qui est l'une des principales causes de cécité à travers le monde. Dans le but d'investiguer les facteurs génétiques impliqués dans cette maladie, nous avons recruté des familles ségréguant le glaucome primaire à angle ouvert (GPAO) et des individus non reliés également atteints de glaucome ou d'hyperpression intraoculaire (HTO). Des mutations du « trabecular meshwork inducible glucocorticoid response gene » (TIGR), ou myociline (MYOC), ont été recherchées parmi 18 familles, représentant 180 individus atteints, et 422 cas sporadiques. La prévalence de mutation de ce gène a été établie à 22,2 et 3,8%, respectivement chez les familles et patients non reliés. Des corrélations génotype/phénotype des mutations identifiées ont été établies. Grâce à la détermination de signatures alléliques entourant le gène TIGR/MYOC, il a été possible d'estimer le nombre de fondateurs ayant contribué à la présence des mutations disséminées dans l'échantillon de la population québécoise testée. Huit familles comportant un nombre suffisant d'individus pour la réalisation d'une étude préliminaire de liaison (linkage) ont été génotypées sur six régions de susceptibilité au glaucome déjà rapportées. Le génotypage de ces familles visait la réduction d’intervalles génétiques associés au glaucome dans le but de découvrir d’autres gène responsables de la maladie. Une famille, représentant un potentiel de liaison intéressant au locus GLC1B, a été élargie dans le but d'augmenter le nombre d'individus atteints possédant un haplotype lié à cette région située sur le chromosome 2cen-q13. Malgré l'identification de gènes candidats intéressants dans ce locus, la saturation de la région chromosomique en marqueurs génotypés chez cette famille a révélé l'absence d'un haplotype commun parmi tous les individus affectés. Le recrutement additionnel de larges familles ségréguant le GPAO et l'élargissement de certains pedigrees déjà prélevés seront nécessaires à l'identification de nouveaux facteurs génétiques jouant un rôle important dans cette pathologie oculaire commune. / The Québec population (~7 million residents) is constituted of approximately six million individuals that descended from an estimated genetic pool of 8500 founders. Utilizing the unique features of this population, this thesis is about the molecular genetics glaucoma, an insidious ocular disease that is a worldwide leading cause of blindness. To study the genetic factors involved in this disorder, we recruited families segregating primary open-angle glaucoma (POAG), and unrelated individuals also affected by glaucoma or ocular hypertension (OHT). Mutations of the TIGR/myocilin (MYOC) gene, until recently the only known genetic cause for juvenile and adult-onset POAG, have been screened in 18 families, representing 180 affected individuals, and 422 sporadic cases. Mutational analysis of this gene showed mutation prevalences of 22,2 and 3,8%, respectively, in families and unrelated patients. Genotype/phenotype correlations of some of the mutations found were established, revealing that the Gly367Arg and Lys423Glu mutations were the most severe. Characterization of allelic signatures surrounding the TIGR/MYOC gene allowed an estimation of the number of founders that may have disseminated the mutations found in the Québec population sample and an evaluation of the possible application of this technique to similar disorders. Eight families with enough individuals to undertake a preliminary linkage study were genotyped on six known glaucoma susceptibility regions. The genotyping of these families aimed the reduction of the genetic intervals of one or more of these known regions to eventually find a new glaucoma-causing gene. One family, representing a strong linkage potential to the GLC1B locus, was extended to have a higher number of affected individuals harboring the candidate disease haplotype linked to this region positioned at chromosome 2cen-q13. Although some interesting candidate genes were identified in this locus, the saturation of the chromosomal region with polymorphic markers revealed the absence of a common haplotype between all the affected individuals of this family. Additional recruiting of large families segregating POAG and the extension of some pedigrees already investigated will be necessary to the identification of new genetic factors closely involved in this common ocular pathology.

In this paper we develop a mathematical model of a two-dimensional aeroelastic airfoil. This model is used to design a flutter suppression controller. Flutter is a vibration in a wing caused by airstream energy being absorbed by the lifting surface. Flutter increases with increasing speed. For simplicity, we consider a flat plate in a two-dimensional flow. The model is developed in the frequency domain and then transformed into the time domain. The uncontrolled model is numerically simulated using MATLAB. Linear Quadratic Regulator (LQR) theory is used to design a state feedback controller. The LQR control scheme consists of using a full state feedback controller of the form u=-Kx, where K is a control gain matrix. The goal is to use LQR theory to supress flutter and to maintain stability of the closed loop system. / Master of Science