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The traditional response to the discovery of a network compromise has been to remove the compromised system from the network, to clean it and to restore it to service. This approach is reactive; a more active approach is necessary and such an approach requires better intelligence collection on attackers. New tools and techniques are required to allow the collection of intelligence on attackers, including the provision of realistic user activity at the human interface device (HID) level. This research developed a conceptual framework for the automatic generation of HID events in a manner that, when observed by attackers, is consistent with a human inputting text into a computer system. The framework, called the Human Interface Device Event Generation Process, accepts a target document as its input and, through sequential transformation, generates a series of mouse and keyboard human interface device events. When placed on the Universal Serial Bus of a compromised computer system, these human interface device events render the composition of the target document by a synthetic user. In order to make the generation of human interface device events consistent with what is expected of a human user, the framework makes use of a User Personality Model which represents the synthetic user’s text composition preferences, editing choices, typing accuracy, use of the mouse and timing characteristics of human interface device events. All of these aspects of the User Personality Model are defined in this research. To demonstrate the validity and feasibility of the framework, we have developed a proof-of-concept Synthetic User Environment which implements the keyboard aspects of the Human Interface Device Event Generation Process framework. The research contributes to the field of computer network defence by providing a framework for the automatic generation of human interface device events, defining User Personality Model components and providing tools for the advancement of Network Counter-Surveillance Operations and Deception Operations.

La réponse typique à la découverte d’une compromission réseau est de retirer le système compromis du réseau, de le nettoyer et de le remettre en service. Cette approche est réactive; une approche plus active est nécessaire et une telle approche requière une meilleure cueillette de renseignement sur les attaquants. De nouveaux outils et techniques sont de mise pour permettre la cueillette de renseignements sur les attaquants, y compris la fourniture d’activité d’utilisateur au niveau de dispositifs d’interfaces humaines. Cette recherche a conçu un cadre conceptuel pour la génération automatisé d’évènements de dispositifs d’interfaces humaines de sorte à ce qu’ils soient consistants, lorsqu’observés par les attaquants, avec un humain composant du texte sur un système informatique. Le cadre conceptuel, appelé le Human Interface Device Event Generation Process, accepte un document-cible comme entrant et, de par une séquence de transformation, génère des évènements pour dispositifs d’interfaces…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Knight, G. Scott.

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A hydrological and water quality model is sought to establish an approach to land management decisions for a Canadian Army training base. Training areas are subjected to high levels of persistent activity creating unique land cover and land-use disturbances. Deforestation, complex road networks, off-road manoeuvres, and vehicle stream-crossings are among major anthropogenic activities observed to affect these landscapes. Expanding, preserving and improving the quality of these areas to host training activities for future generations is critical to maintain operational effectiveness. Inclusive to this objective is minimizing resultant environmental degradation, principally in the form of hydrologic fluctuations, excess erosion, and sedimentation of aquatic environments. In some situations these impacts (particularly sedimentation) could be considered a violation of environmental legislation, such as the Fisheries Act. Application of the Soil Water Assessment Tool (SWAT) was assessed for its ability to simulate hydrologic and water quality conditions observed in military landscapes at 5th Canadian Division Support Base (5 CDSB) Gagetown, New Brunswick. Despite some limitations, this model adequately simulated three partial years of daily watershed outflow (NSE = 0.47-0.79, R2 = 0.50-0.88) and adequately predicted suspended sediment yields during the observation period (%d = -47 to 44%) for one highly disturbed sub-watershed in Gagetown. Further development of this model may help guide decisions to develop or decommission training areas, guide land management practices and prioritize select landscape mitigation efforts.

On cherche à mettre au point un modèle hydrologique et de la qualité de l’eau afin d’établir une démarche de prise de décisions en matière de gestion des terres d’une base d’instruction de l’Armée canadienne. Les secteurs d’entraînement des bases sont le théâtre d’activités intensives et soutenues, qui sont à l’origine de perturbations particulières sur le plan de la couverture et de l’utilisation des terres. La déforestation, la création de réseaux routiers complexes, les manœuvres hors route et la traversée de cours d’eau par des véhicules figurent parmi les principales activités anthropiques observées ayant des incidences sur les écopaysages de ces secteurs. L’expansion, la préservation et l’amélioration de la qualité de ces secteurs pour que les générations futures puissent aussi y mener leurs activités d’entraînement sont essentielles au maintien de l’efficacité opérationnelle. Il s’agit également de réduire au minimum la détérioration de l’environnement découlant de ces activités, principalement les fluctuations hydrologiques, l’érosion excessive et la sédimentation des milieux aquatiques. Dans certaines situations, de telles répercussions (en particulier la sédimentation) pourraient être considérées comme une violation de lois environnementales comme la Loi sur les pêches. On a procédé à une étude sur la capacité de l’outil d’évaluation du sol et de l’eau SWAT à simuler les conditions…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Hulley, Michael.

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The performance of high lift devices such as flaps and slats is an essential part of aircraft design and maintenance. In spite of decades of research however, this complex flow is not yet fully understood by the aeronautical community. In an effort to improve the understanding of the aerodynamic performance of high lift devices, the flow about a cross section of the CP-140 Aurora wing was investigated at various angles of attack in the clean configuration (flap stowed), landing configuration (Fowler flap deployed and deflected to 40º), and the effect of the variation of the flap gap and overlap was quantified. This research included both experimental work using a PIV system as well as numerical simulations using RANS. The focus of the investigation was on the flow behaviour of the boundary layer on the wing trailing edge, as well as on the slot flow. It was found that an increase in flap gap benefited the boundary layer on the wing trailing edge by promoting a fuller velocity profile. In contrast, an increase in flap overlap had a detrimental effect on the wing trailing edge boundary layer. The numerical simulations were validated using the experimental results, and it was found that current commercially available CFD software Fluent 14.0 was not capable of accurately resolving the flow without 'a priori' knowledge of part of the flow conditions. Once the 'a priori' knowledge obtained from the wind tunnel data was integrated into the simulations, the agreement of the 'a priori' simulations with the experiment was good.

La performance des dispositifs hypersustentateurs tels que les volets et becs de bord d'attaque est essentielle pour la conception et l'entretien des aéronefs. En dépit de décennies de recherche, une compréhension complète de ce cas complexe continue à échapper à la communauté aéronautique. Cette thèse détaille une étude expérimentale et numérique d'un écoulement bi-dimensionnel autour d'une aile de CP-140 Aurora équipée d'un volet "Fowler". Cette section transversale de l'aile a été étudiée à différents angles d'incidence dans la configuration lisse (sous volet rétracté), configuration d'atterrissage (volet déployé et ajusté à 40º), et à plusieurs tailles de bâillement et de recouvrement. Cette étude comprend une partie expérimentale utilisant un système de PIV, et une partie numérique utilisant des simulations employant de type "RANS". Cette recherche met l'accent sur la couche limite au bord de fuite de l'aile et de l'écoulement issu du bâillement du volet. Il fut constaté qu'une augmentation du bâillement bénéficie la couche limite sur le bord de fuite de l'aile qui présente un profil de vitesse plus remplis. Une augmentation du recouvrement, par contre, a un effet néfaste sur la couche limite et a finalement provoqué une séparation. Les simulations de configuration d'atterrissage sans la connaissance 'a priori' des conditions d'écoulement issu du bâillement du volet, n'ont pas été résolues avec précision par le logiciel Fluent 14.0. Après les essais en soufflerie, les simulations de…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Ferchichi, Mohsen, Graveline, Sylvain.

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UAVs are gaining great interest due to their wide area of applications in the military and civilian fields. Applying these UAVs autonomously and in a decentralized manner to the accomplishment of various tasks is a growing trend in the field of cooperative robotics. Among these challenging group tasks we find certain UAV tactics, such as dynamic encirclement and formation flights, operating under the umbrella of safe and robust tactic switching. Dynamic encirclement is defined as the situation in which a target is isolated and surrounded by a UAV team in order to maintain awareness and containment of it. Formation flights allow for line abreast, triangle or cross formations while in flight, during which the team members match distance and speed with the others. In this thesis, the problem of switching from formation flights to dynamic encirclement is considered, and a decentralized Linear Model Predictive Control (LMPC) strategy is formulated. Other control techniques such Taylor series linearization (TSL) and Feedback Linearization (FL) are used to linearize the complex tactics models. It is shown, through simulation results and experimental validation, that the designed control policy is effective for a team of N UAVs in formation flights switching to dynamic encirclement of a stationary and moving target. With real-world flight tests, the Qball-X4 quadrotor aircraft is used as a validation platform.

Les drones, appliqu és aux domaines civiles et militaires, ont suscit és un int erêt croissant à cause de leur potentiel. L'utilisation des drones, d'une fa çon autonome et d écentralis ée, pour l'accomplissement de taches vari ées est une tendance croissante dans la communaut é de la robotique coop erative. Parmi ces taches complexes, on trouve des tactiques de drones, tels que l'encerclement dynamique et les vols en formations, o u les v éhicules accomplissent un transfert stable et robuste d'une tactique à l'autre. Limiter le mouvement et avoir conscience d'une cible est consid er é comme partie int egrante de l'encerclement dynamique. Les vols en formations, tels que ligne de front, triangle et croix, permettent aux membres de l' équipe de maintenir les distances et les vitesses requises par rapport aux autres. Dans ce m emoire, le probl ème de transfert stable des vols en formation à l'encerclement dynamique est consid er é et une strat egie de commande pr édictive lin eaire est formul ée. Autres techniques de controles, telles que la lin earisation par s eries de Taylor et la lin earisation par r etroaction, sont employ ées pour simplifi er les mod èles non-lin eaires repr esentants les tactiques. Il est d emontr é, à travers des r esultats en simulation et des validations exp érimentales, que la politique de controle propos ée est e fficace pour une equipe de N drones qui changent de vols en formation à encerclement dynamique. Par rapport aux vols exp erimentaux, le quadrirotor Qball-X4 est utilis é.

Graduate

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Givigi, Sidney.

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The manipulation and organization of text, graphics, and imagery have substantial effects on a reader’s ability to comprehend and retain information. Current military field reporting formats are overwhelmingly text based, with limited consideration as to where an image should be placed, limited use of transferable graphics, and with limited attempts to effectively synchronize these elements. This project has taken lessons from the disciplines of cognitive and educational psychology and used these to develop new templates. Experimentation between the Canadian Army’s current format and the recommended alternative saw an overall percentage improvement of 19.7% and a t-Test score of 3.78. This improvement was echoed by a survey that saw the alternative format rated at 8.3 / 10 in terms of overall utility, compared to optimum forms of the current format that only scored 5.4. This thesis recommends that such results and the structural techniques used to achieve them be considered when designing future interfaces and reporting templates, a program for future evaluation in this area, and a sample design for an automated format that builds on the work conducted thus far.

La manipulation et l'organisation du texte, des graphiques et des images ont des effets importants sur la capacité d'un lecteur à comprendre et à retenir l'information. Les formats actuels des rapports opérationnels militaires sont majoritairement basé sur du texte avec peu de considération pour l'endroit où une image doit être placée, pour utilisation limitée des graphiques et pour le peu d’efforts de synchronisation efficace de ces éléments. Ce projet a pris des leçons dans les disciplines de la psychologie cognitive et éducative et utilisé ces leçons pour développer de nouveaux gabarits. L’expérimentation entre le format actuel de l'Armée canadienne et l'alternative recommandée a vu un pourcentage d'amélioration globale de 19,7% et un résultat t - test de 3,78. Cette amélioration a été observée de nouveau dans un sondage qui a vu le format alternatif évalué à 8,3 / 10 en termes d'utilité générale, par rapport à des formes optimales de la formule actuelle qui a obtenu seulement 5,4. Cette thèse recommande que de tels résultats et les techniques de constructions utilisées pour les atteindre, un programme pour l'évaluation future dans ce domaine et un plan d'échantillonnage automatisé qui s'appuie sur les travaux réalisés à ce jour soient considérés lors de la conception d'interfaces futures et des modèles de rapports.

Graduate

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Hurley, William, St. John, Robert.

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A technique for merging 3D octree occupancy grid maps into a single global map of an evironment is proposed and implemented in software. Octrees are a memory efficient way to represent a 3D environment by recursively subdividing space at multiple depths in a tree structure. The use of an octree representation of a 3D environment allows large environments to be mapped while limiting the amount of memory used in comparison to other techniques. When multiple robots are used to map an environment, a more accurate map of a larger space can be produced in less time. Techniques are introduced to address information from multi-depth sources in each map's tree structure as well as techniques to address relative transformations between maps that are not axis aligned. These techniques allow the octree representation of an environment to be extended to multi-robot applications, specifically those situations where relative map reference frame transformations are unknown prior to mapping. Given the flexibility of this work to situations involving no prior knowledge of map transformations, this work also explores the problem of merging maps when the sources of map transformations are uncertain. Therefore registration techniques using commonly mapped portions of the environment to obtain a better estimate of transformations between maps are explored. The application of these techniques is demonstrated by merging maps built by robots in simulated and real-world environments. The results of this work show that the techniques proposed in this work to merge octree based occupancy grids are valid and that an octree based occupancy grid is a suitable map representation for multi-robot problem spaces requiring a 3D model of the environment.

Une technique pour la fusion de deux mappes représentées en forme de grilles d’occupation octree en 3D vers une seule mappe globale d’un environnement est proposée et implémentée en logiciel. Les Octrees sont efficaces en utilisation de la mémoire pour représenter un environnement 3D en sous-divisant récursivement l’espace dans une structure d’arbre à profondeurs multiples. L’utilisation de la représentation octree d’un environnement 3D nous permet de mapper de vastes environnements tout en limitant la mémoire utilisée en comparaison avec les autres techniques. Lorsque plusieurs robots sont utilités pour mapper un environnement, une mappe plus précise d’un espace plus grand peut être générée en moins de temps. Des techniques sont introduites pour dénouer l’information de différentes sources qui ont une profondeur différente dans chaque structure ainsi que des techniques qui visent les transformations relatives entre les mappes qui ne sont pas alignées sur leurs axes. Ces techniques permettent à la représentation par octree d’un environnement à être portée aux applications multi-robots, spécifiquement dans les situations où les transformations de cadre de référence relatif à chaque mappe sont inconnues avant le mappage. Étant donné la flexibilité de ce travail qui adressent les situations qui…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Givigi, Sidney, Beaulieu, Alain.

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The horizontal orientation of nuclear fuel elements in CANDU reactors presents some unique challenges when it comes to modeling their performance and behaviour under reactor operating conditions. The elements can undergo two different three-dimensional deformation mechanisms during operation: bow and sag. Bowing is the deflection of the fuel elements due to temperature gradients developed across the diameter, and sagging is the deformation at high temperatures due to the self weight of the element. Quantifying these deflections will help determine if element-to-element or element-to-pressure tube contact may occur during reactor operation, possibly causing sheath failure or pressure tube rupture under certain accident conditions. This thesis assesses the feasibility, for CANDU reactor fuel elements, of using the state-of-the-art MOOSE computational framework developed at the Idaho National Laboratory for modeling these three-dimensional deformation mechanisms. This work is the first use of the MOOSE framework in Canada. An application is developed upon the MOOSE framework called HORSE (HORizontal nuclear fuel Simulation Environment) for modeling CANDU fuel. Using HORSE, models are developed that examine the contact capabilities within the framework in two and three dimensions. In addition models are constructed that predict fuel performance, the flexural rigidity of an element, and the thermal bowing behaviour in three dimensions. Assessment and comparison of results against industry codes, numerical models, and analytical solutions are presented. The capabilities of the framework for predicting flexural rigidity and thermal bowing are also discussed. These comparisons demonstrate the potential of the MOOSE framework for developing these complex models. Some additional development of the contact algorithms and inclusion of more nuclear phenomena is required to improve the accuracy for horizontal fuel.

L’orientation horizontale des éléments de combustible nucléaire dans les réacteurs CANDU implique certains défis uniques quant à la modélisation de leur performance et de leur comportement dans les conditions d’exploitation du réacteur. Les éléments sont soumis à deux différents mécanismes de déformation durant l’exploitation: le fléchissement et l’affaissement. Le fléchissement est la déviation des éléments de combustible due aux gradients de température qui se produisent le long du diamètre, et l’affaissement est la déformation à hautes températures causée par le poids même de l’élément. La quantification de ces déflexions devrait aider à déterminer si le contact élément-à-élément ou élément-à-tube de force peut se produire durant l’exploitation du réacteur, et devenir une cause possible de la défaillance des gaines de combustible ou de la rupture du tube de force selon certaines conditions d’accident. Cette thèse évalue la possibilité d’utiliser pour les éléments de combustible du réacteur nucléaire CANDU le logiciel MOOSE développé au Idaho National Laboratory et présentement utilisé pour la modélisation en…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Chan, Paul K., Williams, Anthony F..

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Phthalates are compounds used in a variety of polymers to increase their flexibility and are now ubiquitous in the environment. As few studies have focussed on the adverse effects of these chemicals in aquatic species, this project aimed at elucidating the effects of phthalates in amphibians. Western clawed frog (Silurana tropicalis) tadpoles were acutely exposed to water spiked with monomethyl (MMP), dimethyl (DMP) and dicyclohexyl (DCHP) phthalates. DMP and DCHP were found to be embryotoxic; mortality, malformations and developmental delay were induced in treated larvae. In juvenile frogs, chronic exposures to MMP led to increased mortality, accelerated metamorphosis and more recurrent male phenotypes. However, MMP did not have considerable adverse health effects in tadpoles nor adult frogs. Moreover, analysing the expression of selected genes increased our understanding of the mechanism of phthalates. This is the first study to thoroughly investigate the effects of phthalates in the entire amphibian life cycle (egg to adult stage). These assays provided valuable data that will help better assess and manage the risks brought on by the production and the use of phthalates in the Canadian environment. Les phthalates sont des composés utilisés dans une variété de polymères afin d’accroître leur flexibilité et sont maintenant omniprésents dans l’environnement. Comme peu d’études ont caractérisé les effets de ces produits chimiques chez les espèces aquatiques, ce projet avait pour but d’élucider les effets des phthalates chez les amphibiens. Des têtards du Xénope tropical (Silurana tropicalis) ont été exposés à de l’eau contaminée avec du phthalate monométhylique, du phthalate diméthylique et du phthalate dicyclohexylique. Les phthalates diméthylique et dicyclohexylique se sont révélés embryotoxiques; les composés ont induit de la mortalité, des malformations et des délais de développement chez les larves. Chez les grenouilles juvéniles, les expositions chroniques au phthalate monométhylique ont mené à de la mortalité, à l’accélération de la métamorphose et à des phénotypes masculins plus fréquents. Le phthalate monométhylique, par contre, n’avait pas d’effets considérables chez les têtards ni chez les grenouilles adultes. De plus, l’analyse de l’expression d’une série de gènes a accru notre compréhension du méchanisme d’action des phthalates. Cette étude est la première à enquêter de manière approfondie les effets des phthalates sur l'ensemble du cycle de vie des amphibiens (œuf à adulte). Ces expériences ont fourni de précieuses données qui aideront à mieux évaluer et gérer les risques associés à la production et l'utilisation des phthalates dans l'environnement canadien.

Graduate

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Langlois, Valérie S..

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Finite elements analysis is often used to predict the behaviour of composite materials as the use of analytical calculations is limited by the complexity the material's stress state. Although the Classical Laminate Theory (CLT) can be used to determine in-plane stress, it cannot be used to determine interlaminar stress as this theory presumes an inplane state. The analysis of composite materials is possible through various commercial finite element analysis software packages available on the market. The objective of the present study was to develop a methodology to predict the distribution of the interlaminar stress in a 4-point bending test in order to ultimately study the relation between laminate fatigue behaviour and the values of interlaminar stress at the edges. Three finite elements analysis software packages (ANSYS, Stress Check and PATRAN/NASTRAN) were used to develop a consistent method for modeling and results extraction. The numerical predictions obtained from the laminate model [(0/90)4]s have shown a defection comparable to the experimental testing results. The laminate's displacement values (defection) are the same with both the numerical and experimental results despite the simplicity of the modelling used. The macroscopic modelling approach, where each ply is defined by an orthotropic and homogenous material, generated stress singularities to the plies' interface at the edges. These singularities are caused by a discontinuity in the material properties of the neighboring plies. However, the out-of-plane interlaminar stress tends to converge when examined at a specified distance from the free edge. A convergence zone was established by estimating the stress variation in accordance with the number of degrees of freedom in the model. Using the P-method, the convergence zone was precisely defined by varying the polynomial degree while keeping the position of the elements identical on each model. The maximum value of the interlaminar stress cannot be determined with the model used, however, by determining the maximum interlaminar stress in the convergence zone a comparison of various laminates can be done. The interlaminar stress for three types of laminates was assessed. The number of plies and the orientation of the reinforcements were defined in order to obtain laminates with similar bending stiffness but with varied interlaminar stress. The three laminates analysed [(0/90)4]s,[0/65/90/65/0/65/90/65/0]s et [0/45/90/45/0/45/90/45/0]s produced low, medium and high values of interlaminar stress. In conclusion, developing a method for consistently comparing interlaminar stresses aid in determining whether a correlation between interlaminare and fatigue behaviour exists.

La complexité de l'analyse des contraintes des matériaux composites limite l'utilisation des calculs analytiques, rendant l'analyse par éléments finis souvent nécessaire. Alors que la théorie classique des stratifiés (TCS) peut être utilisée pour déterminer les contraintes dans le plan, les contraintes interlaminaires ne peuvent ^être…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Wowk, Diane, Marsden, Catharine.

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Although broadband photometry has been used to infer information about artifcial satellites since soon after the launch of Sputnik 1, to date there has not been a coherent progression of understanding regarding the information that can be obtained, and the most effective methods of doing so. Many individual studies, and some long ongoing experiments, have used costly metre-class telescopes to obtain data despite other experiments demonstrating that much more flexible and affordable small aperture telescopes may be suitable for the task. In addition, due to the highly time consuming and weather dependent nature of obtaining photometric observations, many studies have suffered from limited data sets or relied upon simulations to support their claims. Therefore, an experiment was conducted with the aim of determining the utility of small aperture telescopes for conducting broadband photometry of satellites. A small aperture telescope (Celestron CG-14, 35.6 cm aperture) was used to gain multiple night-long, high temporal resolution data sets of a limited number of geostationary satellites (Anik F1, Anik F1R, Anik G1, Echostar 17, Galaxy 11, and Intelsat 805). The results of the experiment demonstrate that small aperture telescopes can be highly effective for obtaining accurate photometric measurements of geostationary satellites. In the process some novel discoveries were made that cast doubt on the effi cacy of some of the previous approaches to obtaining and analysing photometric data. For example, it was discovered that satellite lightcurves vary to a significantly greater degree than has been generally recognised, and significant features such as oscillations were detected in some lightcurves with frequencies higher than would be detectable at temporal resolutions that have typically been employed in the past. Furthermore, these results suggest that high temporal resolution, simultaneous, multicolour observations may have significant utility in characterising or identifying satellites in some cases.

Bien que la photométrie à large bande ait été utilisée pour obtenir de l'information sur les satellites artificiels peu de temps après le lancement de Sputnik 1, il n'y a pas eu jusqu'à maintenant une progression cohérente dans la compréhension de l'information pouvant en être déduite, ainsi que sur les méthodologies les plus efficaces. Plusieurs études individuelles et quelques longues expériences toujours en cours ont fait l'usage de télescopes dispendieux de la catégorie des mètres pour obtenir des données malgré que d'autres expériences aient démontré que des télescopes â petite aperture beaucoup plus flexibles et abordables peuvent être convenables pour la tâche. De plus, étant donné la variabilité de l'état du ciel et le cout élevé en temps pour obtenir des observations photométriques, plusieurs études reposaient sur des ensembles de données limités ou bien sur des simulations afin d'appuyer leurs allégations. Par conséquent, une expérience a été conduite ayant comme objectif d'évaluer l'utilité des télescopes à…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Wade, Gregg.

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Piezoelectric materials are used in an increasing number of applications and submitted to a wide range of temperatures, frequencies, pressures, and voltages. Such diverse environmental conditions result in a non-linear piezoelectric response that is difficult to characterize, and the presence of impurities, dopants, and defects add to the complexity of predicting how a material will perform once it is manufactured, especially given the sensitivity of the manufacturing process. Also, recent environmental regulations require new lead-free piezoelectric materials to be developed and studied. The object of this thesis is to further the knowledge with respect to the structural, ferroelectric, dielectric, and electromechanical properties of piezoelectric and electrostrictive materials in order to facilitate the development of new piezoelectric materials and help optimize current applications. Scanning electron microscope pictures of EC-65, EC-69, and EC-76 were taken, and X-ray diffraction patterns of PLZT 9.5 were obtained at room temperature. Polarization curves were obtained for EC-65, PLZT 9.5, BM-941, BM-600, BM-150, and PMN-PT for electric fields ranging from 0 to ±1000 kVm-1 and temperatures ranging from -40°C to 120°C. Impedance analysis was used to determine the relative permittivity and the dielectric loss tangent of EC-69, PLZT 9.0, PLZT 9.5, and BM-941 for electric fields ranging from 0 to ±2000 kVm-1 and temperatures ranging from -40°C to 140°C with frequencies ranging from 1 kHz to 5000 kHz. Finally, the AC strain amplitude of PLZT 9.0 and BM-941 were obtained for AC electric fields ranging from 0 to ±1000 kVm-1 and a DC bias ranging from 0 to ±1500 kVm-1. Overall, the measurements obtained build upon the current knowledge of piezoelectric materials, support results obtained by other researchers, and present new results that can be used to develop new materials and optimize current applications.

Les matériaux piézoélectriques sont utilisés dans un nombre croissant d’applications les soumettant à un large éventail de températures, de fréquences, de pressions et de voltages. Ces conditions environnementales instables engendrent une réponse piézoélectrique non-linéaire qui est difficile à caractériser. De plus, la présence d’impuretés, de dopants et d’imperfections rendent le processus de production et de fabrication précaire et instable. Puis, de nouvelles lois environnementales exigent une diminution de l’utilisation du plomb dans l’industrie de l’électronique et exigent que de nouveaux matériaux piézoélectriques sans plomb soient développés. L’objectif de cette thèse est d’améliorer les connaissances des propriétés structurelles, ferroélectriques, diélectriques et électromécaniques des matériaux piézoélectriques et électrostrictifs afin de faciliter le développement de nouveaux matériaux piézoélectriques et d’optimiser les applications actuelles. Des images de EC-65, EC-69 et EC-76 ont été prises par microscopie électronique à balayage et des réseaux de diffraction à rayons X de PLZT 9.5 ont été…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Sabat, Ribal Georges.

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Non-destructive testing has become a valuable inspection tool for the aerospace industry. In particular, eddy current testing is used extensively to detect surface and near surface defects in aluminum aircraft component structures. However, there exists a requirement to inspect for the presence of cyclic fatigue cracks around ferrous fasteners in the second layer of double layer structures, such as the lap-joint of the CP-140 Aurora, and CC-130 Hercules. These defects are not easily detectable by conventional eddy current techniques, unless the fasteners are removed. A capability to inspect through the top layer would avoid fastener removal, in turn reducing down time and risk of collateral damage to the structure. Pulsed eddy current (PEC) is an emerging technique with the potential to detect cyclic fatigue cracking in the second layer of aluminum wing structures. PEC offers potential advantages over conventional eddy current in that the inspection occurs from the top layer, does not require fastener removal and the diffused magnetic field can be sensed at greater depths within the material. However, the time-domain PEC signals show only subtle differences between the presence or absence of cracks. Principal components analysis (PCA) is a statistical tool that can be used to reduce the time domain signal to a small number of scores, which enhance the distinction between PEC signals. These scores are clustered depending on whether a crack is present. The relative distance (Mahalanobis Distance), between the scores for a crack and the centroid of the scores for fasteners with no crack can be used to distinguish between cracks and non-cracks. A PEC coil-based probe was tested on three lap-joint samples containing ferrous fasteners, two of which were actual CP-140 Aurora airframes, and one that was fabricated in the lab. Simulated flaws, ranging in size from 0.8 - 5.5 mm, were present in both the top and bottom aluminum layers. One hundred percent of the simulated flaws were detected in two of the samples with top sheet thickness of 2 mm, and 82% in a thicker (2.6 mm thick first layer) airframe section with a different fastener type, all at 5% false call rate. An observed correlation between Mahalanobis Distance and crack size also suggested that sizing of second layer cracks is possible.

Le contrôle non destructif est une technique de grande valeur pour l’industrie aérospatiale. En particulier, les courants de Foucault sont largement utilisés pour détecter les défauts de surface ou proche de la surface des composantes en aluminium dans les avions. Des critères d’inspection existent pour estimer la présence de fissures dues à la fatigue cyclique autour des attaches en fer au niveau de la deuxième couche d’une structure à deux couches, comme les joints de recouvrement des ailes des avions Aurora CP-140 et Hercule CC-130. Ces défauts ne sont pas détectables facilement avec les méthodes de courants de Foucault conventionnelles, à moins que les attaches en fer soient retirées. La capacité d’accomplir l’inspection à…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Krause, Thomas, Underhill, Ross.

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Plasma instabilities play an important role in producing small-scale irregularities in the ionosphere. In particular, current-driven electrostatic ion-acoustic (CDEIA) instabilities contribute to high-latitude F-region electrodynamics. CDEIA instabilities are affected by ion velocity shears and temperature anisotropies. Ion temperature anisotropies with perpendicular enhancements often exist in the high-latitude F-region. In addition to temperature anisotropies, ion velocity shears are observed near auroral arc edges, sometimes coexisting with thermal ion upflow processes and field-aligned currents (FAC). We investigated whether ion temperature anisotropy or shears lower the threshold conditions required for the onset of CDEIA instabilities and also, enhance the incoherent scattering from ion-acoustic waves. We generalized a dispersion relation to include ion thermal anisotropy, finite Larmor radius corrections and collisions. We derived new fluid-like analytical expressions for the threshold conditions required for instability. We studied how the instability threshold conditions vary as a function of the wave vector direction in both fluid and kinetic regimes. We found that, in some cases, ion temperature anisotropy lowers significantly the threshold drift requirements for a large range of intermediate aspect angles. In particular, realistic ion temperature anisotropies contribute to reducing the instability threshold velocity shears that are associated with small relative drift thresholds, for modes propagating almost perpendicularly to the geomagnetic field. Such instabilities could play a role in the direct generation of field-aligned irregularities in the collisional F-region that could be observed with the Super Dual Auroral Radar Network (SuperDARN) array of high-frequency radars. These modes would be very sensitive to the radar probing direction since they are restricted to very narrow angular intervals. On the other hand, our study confirmed that temperature anisotropies in magnetized plasmas are unimportant when the incoherent radar is pointing at the critical angle for which the total temperature is equal to the effective temperature. Yet, under the right conditions, “small” ion velocity shears produce significant enhancements in ISR spectra, especially for directions near perpendicular to the geomagnetic field. This could lead to overestimations of the interpreted electron to ion temperature ratio and electron density when using standard ISR fitting procedures. In closing, ion temperature anisotropies and velocity shears are important parameters that need to be considered in the studies of CDEIA waves and instabilities in the high-latitude F-region, especially for propagation directions near perpendicular to the geomagnetic field.

Les instabilités du plasma jouent un rôle important dans la production d’irrégularités à petite échelle au sein de l’ionosphère. En particulier, les instabilités électrostatiques ion-acoustiques déclenchées par courants contribuent aux processus électrodynamiques de la région…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Noël, Jean-Marc.

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The aim of this study was to investigate the impact of saltwater intrusion on the transient hydraulic behavior of coastal aquifers and to develop an Equivalent Freshwater Modeling (EFM) approach. The EFM approach proposed here focuses on the use of an Equivalent Freshwater Hydraulic Conductivity. A two dimensional finite difference saltwater/freshwater model was developed using SEAWAT. An equivalent two dimensional freshwater-only model was also developed using MODFLOW. Both saltwater/freshwater and freshwater-only models were run under different recharge and pumping conditions. A comparison between the two models’ behaviour was held to identify possible relationships between the hydraulic conductivity (Ks) of the saltwater/freshwater model and the hydraulic conductivity (Kf) of the freshwater-only model. For each value of Ks a calibration exercise was performed to choose the equivalent Kf value that gives the minimum Root Mean Square Error between the two models. Plots of the relationship between Ks and the optimal Kf values were generated for a range of Ks values and for a range of pumping conditions represented by the ratio of pumping rate over the freshwater lens thickness, (Q/Bf). The optimal Kf values were then tested with three dimensional models. From the different simulation scenarios we found that the presence of saltwater intrusion does not significantly affect the behavior of fine sand aquifers (Ks < 5 m/d), under the full range of pumping and freshwater lens thicknesses considered in this study. In medium sand aquifers (10 < Ks < 25 m/day), the presence of the intrusion requires an Equivalent Freshwater Hydraulic Conductivity (Kf) that is 20 to 30% higher than the original value, but the required Kf is fairly independent of the pumping over the freshwater lens thickness ratio (Q/Bf) In coarse sand aquifers (Ks > 45 m/day), the saltwater presence does have a significant effect on the aquifer behavior and the ratio of Kf over Ks is significantly affected by the freshwater lens thickness and the pumping rate. The 3-D model verifications, that were performed with Fine Sand and Medium Sand Hydraulic Conductivities only, confirmed the Kf /Ks relationships that were developed with the 2-D models. The performance of the EFM approach was found to depend on the aquifer hydraulic conductivity, the freshwater lens thickness and the intensity of the pumping applied to the models.

Le but de cette étude était d’investiguer l’impact des intrusions salines sur le comportement hydraulique transitoire des aquifères côtiers et de développer une approche de Modélisation Équivalente d’Eaux Douces (MEED). L’approche MEED proposée ici, est axée sur l’utilisation d’une Conductivité Hydraulique d’Eau Douce Équivalente. Un modèle bidimensionnel eaux salines / eaux fraiches en différence finies a été développé à l’aide de SEAWAT. Un modèle bidimensionnel eaux fraiches équivalent a aussi été développé avec MODFLOW. Les deux modèles ont été exécutés sous différentes conditions de recharge et de pompage. Une comparaison…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Tetreault, Michel, Hulley, Michael.

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Aircrews of commercial aircraft are exposed to higher doses of ionizing radiation than members of the general population in most parts of the world. The principal ionizing radiation to which aircrews are exposed is galactic cosmic radiation (GCR), which comes from outside our solar system. Among the most enigmatic particles present in the primary GCR spectrum are the so called heavy ions; atoms that are stripped of all electrons and traveling at relativistic speeds. They can cause unique biological injury that remains poorly understood. This research seeks to improve the evaluation of dose rates at altitudes up to the edge of space resulting from these ions. Secondary particle spectra produced by mono-energetic showers of neutrons and GCR ions up through iron at 18 altitudes from 0-100 km were calculated by means of Monte Carlo simulations using MCNPX 2.7.0. These spectra were converted to doses per unit fluence of the incident primary particle using fluence-to-dose conversion coefficients or were summed in order to provide secondary particle flux per unit primary flux for 37 secondary particle types. Results were collected into databases for rapid numerical integration. A magnetic pass-band filter with a Kp-index-based correction function was constructed based on vertical magnetic cutoff rigidity to account for magnetic shielding prior to particles reaching the atmosphere. The atmosphere was modelled from the 1976 U.S. standard atmosphere. Multiple GCR models were used as sources to drive the model. Solar activity was accounted for using GCR model specific parameters. Neutron monitor data was used to account for Forbush decreases. Calculations with CARI-7, the resulting rapid computer software model, compare well with measurements and dose calculations of others, but also show the characteristic shortcomings of modeling GCR showers without including local magnetic effects on particle path lengths and directions. Superposition, an approximation commonly used in modern flight-dose calculations, slightly increases effective dose rates at altitudes below 16.3 km and severely decreases them at higher altitudes, where increased ionization from heavy ions in the primary GCR flux and their large radiation weighting factors can result in effective dose estimates as high as 76 microseivert per hour.

Les membres d’équipage d’avions de ligne commerciaux sont exposés à de plus grandes doses de rayonnement ionisant que les membres de la population générale vivant dans presque toutes les parties du monde. Les membres d’équipage des avions de ligne sont surtout exposés au rayonnement cosmique galactique qui provient de l’espace hors de notre système solaire. Les ions lourds sont parmi les particules les plus énigmatiques composant le spectre du rayonnement cosmique galactique primaire et comprennent des atomes qui ont perdu tous leurs électrons et qui se déplacent à des vitesses relativistes. Ils peuvent causer des dommages biologiques importants qui demeurent peu compris. La présente recherche vise à améliorer…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Lewis, Brent J., Corcoran, Emily C..

▼ The presence of pharmaceuticals and personal care products are increasing in our natural environment due to their incomplete removal within traditional wastewater treatment plants. Constructed wetlands are used as secondary or tertiary wastewater treatment and as such may receive both pharmaceuticals and personal care products with subsequent implications for their treatment efficacy. The aim of this study was to examine the fate and effects of antimicrobials in planted and unplanted vertical flow constructed wetlands. Twelve mesocosms were inoculated with activated sludge from the Cataraqui Bay Wastewater Treatment Plant. Six were planted with reed canary grass (Phalaris arundinacea) and the remaining six were left unplanted. The wetland mesocosms were assessed using a variety of parameters including water treatment (chemical oxygen demand removal rate), hydrological (porosity, evapotranspiration/evaporation) water quality (temperature, pH, specific conductivity, dissolved oxygen, redox potential, total dissolved solids), ecological (plant height and stem count), and microbial community function (community level physiological profiling).. Community-level physiological profiles were gathered for the wetland microbial community using Biolog EcoplatesTM. The development phase was initially characterized for all mesocosms over a ninety-day period to establish ecological stability. The microbial communities were then subjected to ex-situ, dose-response exposures (0 – 1000 μg/L) for trimethoprim, triclosan and sulfamethoxazole to gain an understanding of the ecotoxicity of these antimicrobials. Following the ex-situ exposures, in-situ exposures were performed with triclosan and sulfamethoxazole at low (100 μg/L) and high (500 μg/L) concentrations. The low concentration was selected based on literature reviews of the levels found in water bodies and the high concentration was selected to represent a shock-loading scenario. Hydrological, ecological and microbial parameters were monitored before, immediately after and over a recovery period of four weeks following each exposure. During the developmental period both the planted and unplanted mesocosms developed similarly and ecological stability was established. However, a distinct microbial community profile was observed in the planted mesocosms. In the ex-situ dose-response experiments the effect of trimethoprim was negligible on the planted microbial communities but with some removal of microbial function for the unplanted microbial communities. Triclosan exposure led to a moderate decline in microbial function for both the planted and unplanted communities. Sulfamethoxazole exposure led to a severe decline in microbial function in both the planted and unplanted microbial communities, so much so that negligible activity was observed at 1000 μg/L. Following the in-situ low and high exposures of triclosan and sulfamethoxazole there was a significant removal of the compounds (>80%) from the mesocosm water column. The effects of both low and high triclosan and sulfamethoxazole… Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Weber, Kela.

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Organic molecular glasses are considered as an important category of organic functional materials that have attracted increasing attention in technical applications. The ability of these compounds to produce amorphous uniform thin films that are easy to process, makes them appealing candidates as chromophores, semiconductors and charge transport materials in several fields such as organic electronics, optoelectronics, and photonics. The advantages associated with these amorphous molecular materials, such as small size and low molecular weight, make the process of characterization and purification easier. In our research group, molecular glasses functionalized with selected electron transporting groups have been designed, synthesized, and characterized. Also corresponding molecular and physical properties have been investigated by DSC (differential scanning calorimetry) and UV-Vis spectroscopy. In this research thesis strategies to design and synthesize glasses functionalized with perylenediimide (PDI) dyes and fullerenes and corresponding properties will be discussed

Les verres moléculaires organiques sont une famille importante de matériaux fonctionnels organiques qui ont suscité beaucoup d'intérêt pour certaines applications techniques. La capacité de ces composés de former des couches minces amorphes uniformes qui sont faciles à mettre en oeuvre fait de ces matériaux des candidats idéaux comme chromophores, semiconducteurs ou transporteurs de charge dans des domaines tels que l'électronique organique, l'optoélectronique et la photonique. La petite taille et la basse masse moléculaire de ces composés leur procure des avantages au niveau de la purification et de la caractérisation. Dans notre groupe de recherche, nous avons conçu, synthétisé et caractérisé des verres moléculaires fonctionnalisés avec des groupes transporteurs d'électrons. De plus, nous avons déterminé leurs propriétés physiques à l'aide de la calorimétrie différentielle à balayage (DSC, differential scanning calorimetry) et la spectroscopie UV-Visible. Le but principal de cette thèse est de discuter des nouvelles stratégies mises au point pour la conception et la synthèse de verres moléculaires fonctionnalisés avec des colorants pérylènediimides (PDI) et des fullerènes.

Graduate

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Lebel, Olivier.

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The problem is to find the best location of a minisum annulus with given width using the partial coverage distance model. The concept of partial coverage distance is that given demand points in the covering area are covered at no cost, while for uncovered demand points there will be additional costs proportional to their distances to the covering area. The objective of the problem is to locate the annulus such that the sum of distances from the uncovered demand points to the annulus (covering area) is minimized. The distance is measured by the Euclidean norm. We discuss the cases where the radius of the inner circle of the annulus is variable and given. For the variable radius, we prove that at least two demand points must be on the boundary of any optimal annulus. Based on that, an algorithm to solve the problem is introduced. In the case of given radius, we introduce the model and show its usefulness in locating undesirable facilities.

Le problème est de repérer le meilleur emplacement d’un espace annulaire avec des données de la largeur en utilisant le critère mini-somme et un modèle à distance avec couverture partielle. La notion de distance avec couverture partielle est que les points dans la zone de couverture sont servis sans pénalité, mais il y aura, pour la découverte des points, un surcoût proportionnel à leur distance de la zone de couverture. L’objectif du problème est de localiser l’espace annulaire tel que la somme des distances comprises entre les points non couverts par l’espace annulaire (superficie) réduit au minimum. La distance est mesurée par la norme euclidienne. Nous discutons les cas où le rayon du cercle intérieur de l’espace annulaire est variable et donné. Pour le rayon variable, nous avons prouvé qu’au moins deux points devaient être sur la limite d’un anneau optimale. Sur cette base, un algorithme pour résoudre le problème est introduit. Dans le cas d’un rayon donné, nous introduisons le modèle et nous prouvons son utilité en localisant des installations indésirables.

Graduate

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Brimberg, Jack.

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Autonomous thermal soaring aircraft exploit the use of naturally occurring updrafts to increase their overall energy state. Thermal soaring strategies for these types of aircraft have been developed and refined to increase aircraft range and/or endurance performance through pilot flying experience and an increased knowledge of gliding flight theory. Current autopilot development for thermal centring control makes use of analytical expressions or accepted soaring techniques for their implementation. The use of trajectory optimization to analyze thermal centring strategies has been very limited given the numerical difficulties encountered when analyzing the problem in a Cartesian coordinate system. In this study, the generalized aircraft equations of motion are restructured in cylindrical coordinates, to reduce numerical computational issues arising during optimization, and are augmented with wind component forces. To generate optimal trajectories for autonomous thermal soaring, the optimal control problem is defined as maximizing either the aircraft’s instantaneous or final specific energy state and the trajectories are solved using a direct collocation method using nonlinear programming. Optimal flight trajectories are presented for a small autonomous aircraft operating in multiple thermal profiles of varying strengths. These trajectories are compared to the derived analytic expressions and a thermal centring strategy for controller development is presented. As an application, optimal flight trajectories are presented that maximize thermal energy extraction whilst providing persistent aerial surveillance coverage for a variety of thermal and target locations.

Le vol à voile autonome utilise le vol thermique pour accroître leur énergie. Des stratégies de vol thermique ont été développées et améliorées pour accroître la distance franchissable et/ou le temps de vol en utilisant l’expérience des pilotes ou la mécanique du vol plané. La commande de positionnement sur l’ascendant thermique des pilotes automatiques actuelles est basée sur des expressions analytiques ou des techniques de vol connues. L’emploie d’optimisateur de trajectoire pour déterminer la commande de positionnement est prescrit dû aux difficultés numériques lors de l’analyse en coordonnées cartésiens. Pour cette étude, les équations générales du mouvement sont réécrites en coordonnées cylindriques, afin de réduire les difficultés numériques durant l’optimisation et sont accompagnées de composantes de la force du vent. La commande optimale par méthode de point intérieure non linéaire est utilisée pour générer les trajectoires optimales en vol thermique et est définie comme le maxima de l’énergie instantanée ou de l’énergie finale. Les trajectoires optimales sont présentées pour de petit aéronef autonome volant dans de multiple profiles d’ascendant thermique de force différente. Ces trajectoires sont comparées avec les expressions analytiques et stratégies de positionnement. Comme exemple d’application, les trajectoires optimales maximisant l’apport…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Perez, Ruben.

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Point Pelee National Park (PPNP), located in Leamington, ON, is heavily contaminated with the pesticide dichlorodiphenyltrichlorethane (DDT) which was liberally used for mosquito and pest control in the Park from the 1940s until the 1960s. Building on previous research, a comprehensive soil and sediment sampling and analytical program was carried out. Using the data obtained, contamination boundaries were defined and it was determined that DDT contamination was centred in three major hotspot areas. This information was mapped into an interactive Google Earth platform. DDT isomer analysis compared different groupings of samples, and determined that each of the soil hotspot areas have comparable degradation rates with half-lives ranging from 27 to 40 years. The sediments from the ponds and marsh areas had statistically different isomer compositions and degradation pathways than the soil with half-lives of 18 to 25 years. Finally, a remediation options analysis was conducted and courses of remedial action are suggested. This information and the Google Earth overlay is being provided to Point Pelee Park staff so they can more strategically approach long-term park management.

Le parc national de Point Pelee (PNPP), situé à Leamingston Ontario, est largement contaminé avec le pesticide dichlorodiphenyltrichlorethane (DDT) qui fut largement utilisé pour le contrôle des moustiques et de la peste pendant les années 1940 jusqu’en 1960. Se basant sur des recherches antérieures, un programme d’échantillonnage et d’analyse de sédiments et de sols fut complété. En utilisant les données obtenues, les limites de la contamination ont été définies et il a été déterminé que la contamination au DDT était centrée autour de trois point chaud. Cette information a été cartographiée sur une plateforme interactive Google Earth. L’analyse d’isomère DDT a comparé les différents groupes d’échantillons, et a déterminé que les sols de chaque secteur avaient tous des taux de dégradations comparable avec des demi-vies de 27 à 40 ans. Les sédiments des secteurs de marais et d’étangs avaient des compositions d’isomère et des taux de dégradation statistiquement différents avec des demies-vie de 18 à 25 ans. Finalement, une analyse d’option de dépollution fut menée et les options d’analyse de dépollution sont suggérées. Cette information ainsi que l’information cartographiée de Google Earth sont également fourni aux employés du parc Pelee de manière a ce qu’ils puissent établir une meilleur stratégie de gestion du parc a long terme.

Graduate

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Zeeb, B, Rutter, A.

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Airborne radioactive particulates constitute a significant hazard facing military members, emergency personnel, and the immediate public in any nuclear-related incident. Personal protective equipment (PPE) can be used to reduce wearer exposure to emitted radiation; however, existing PPE suits do not effectively attenuate all types of radiation and, thus, cannot offer complete protection in response to radiological hazard scenarios. In light of the Fukushima-Daiichi incident, it is evident that rigorous investigation and research needs to be undertaken in order to resolve this issue and to garner a better understanding of the level of protection provided by current PPE concepts. The objective of this thesis is to develop a realistic dosimetric model of the human forearm, protected by a PPE sleeve, which can be used to determine the dose imparted to the tissue in the event of radiological particulate exposure. A two-fold approach is employed whereby: (1) a particle transport model is used to determine the concentration of radioactive particulates in five regions surrounding the forearm (both within and outside the PPE sleeve); and (2) these concentration data are then incorporated into a dosimetric model that uses the Monte Carlo N-Particle (MCNP) transport code to determine the dose imparted to the tissue. Nine modelling cases, representative of a combination of the three most likely radionuclide species (Co-60, Sr-90, and Cs-137) facing emergency personnel during a radiological dispersion event and three different PPE sleeve concepts (air impermeable fabric with closure leak, perfectly sealed air permeable fabric, and no shielding), were selected for analysis. The preliminary model developed in this thesis was successfully able to determine the dose imparted to a human forearm as a result of exposure to radioactive particulates released in a dispersion event. The results indicate that the ability of the fabric to limit the transport of radioactive particulates has a greater impact on reducing the imparted dose than its ability to attenuate the incident radiation. A number of improvements to the model are proposed and discussed, such that it may be extended to consider more accurately particulate infiltration processes and whole-body dose and be used as a tool for Canadian Armed Forces (CAF) commanders during radiological emergencies.

Les macro-particules radioactives aéroportées représentent un danger important pour les militaires, le personnel des urgences et le public immédiat lors d’incidents de nature nucléaire. L’équipement de protection personnelle (ÉPP) peut être utilisé afin de réduire l’exposition du porteur aux rayonnements émis; cependant, les vêtements d’ÉPP existants ne peuvent pas atténuer de manière efficace tous les types de rayonnement et, par conséquent, ils ne peuvent pas offrir une protection complète dans tous les scénarios de danger nucléaire. À la lumière de l’incident de Fukushima-Daiichi, il est évident qu’une enquête et une recherche rigoureuses doivent être entreprises pour…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Corcoran, Emily C., Dickson, Eva G..

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The study of fatigue crack growth for damage tolerance analysis is of interest to the aerospace industry to enable accurate and economical estimates of a component’s life before replacement or repairs are required. Many numerical analyses used for damage tolerance employ a series of assumptions that enable results to be generated quickly at the cost of accuracy. With advances in computational power and numerical analyses some of these assumptions, such as crack shape, are not necessary and not including the assumptions in the analysis result in more accurate fatigue predictions. This thesis presents the development and application of an automated crack growth program, called the ACGP, to predict crack growth and fatigue life in non-standard geometries, where the shape of the crack front is determined iteratively. The ACGP was developed using a simulated growth technique and employed finite element analysis and Paris growth equations to predict fatigue crack growth of cracks in thin plates. The ACGP was validated for predictions of fatigue life and crack growth that were found to agree with experimental and accepted numerical results. The predictions were also compared to results generated using the fatigue crack growth program AFGROW and differences and similarities are presented. Models were also created to predict crack growth emanating from countersunk fastener holes in thin plates. Assessment and comparison of the results are presented, identifying the growth pattern, critical initial location and the effect of geometric properties on the fatigue life.

L’étude de la résistance, la durabilité et la tolérance aux dommages des matériaux est d’intérêt à la communauté aérospatiale pour améliorer la sécurité et estimer de la durée de vie de composantes en avance d’un remplacement ou d’une réparation. Plusieurs des méthodes numériques employées pour l’analyse de la tolérance aux dommages utilisent des hypothèses simplificatrices permettant un calcul rapide au dépend de la précision. Des progrès en informatique et en analyse numérique ont rendu certaines de ces simplifications redondantes, tel que la géométrie des fissures, et, en conséquence, les prédictions de la vie en fatigue sont devenues plus précises. Cette thèse discutera du développement et l’application d’un programme informatique capable de prédire la propagation des fissures et la résistance en fatigue pour les cas de géométries hors norme, où la géométrie de la fissure est déterminée de façon itérative. Le programme de prédiction automatisé de propagation de fissure, appelé ACGP, emploi une technique de simulation de propagation, une méthode des éléments finis et les équations de croissance de Paris pour prédire la propagation des fissures dans un plaque mince. Les prédictions de l’ACGP de la vie en fatigue et la propagation des fissures se comparent bien avec des résultats expérimentaux et numériques. Les résultats de l’ACGP ont été aussi validés contre ceux du programme informatique en analyse de fatigue AFGROW, et les similarités et différences sont…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Wowk, Diane.

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Biogas is a renewable-energy by-product produced at many wastewater treatment plants (WWTPs) by anaerobic digestion. Unfortunately, biogas is currently underutilized at smaller facilities because of the capital and maintenance capital costs associated with combined heat and power (CHP) technologies and biogas purification. Solid oxide fuel cell (SOFC) systems are a CHP technology currently entering commercial markets that could lead to a rise in biogas utilization at WWTPs because they are the CHP technology with the highest electrical efficiencies and most environmentally-friendly emissions profiles.

A 2kWe biogas-fed SOFC pilot plant has been proposed for construction at the Ravensview wastewater treatment plant in Kingston, ON, that is to be directly integrated with one of the on-site digesters. Importantly, the pilot plant will include a biogas purification system comprised of inexpensive adsorbents that selectively targets the two most detrimental contaminant species, hydrogen sulphide and siloxanes.

This work began with an experimental component in which a prospective SOFC stack for the pilot plant was operated on processed biogas. Subsequently, a process model of the pilot plant was developed using the UniSim Design simulation software. The process model is enhanced by the inclusion of a tunable empirical cell model that was calibrated to the prospective stack performance. A series of sensitivity analyses were performed on the pilot plant model which revealed that the system could be operated on the expected range of biogas compositions generated at WWTPs. The maximum feasible gross electrical and CHP efficiencies were estimated to be 62 and 77 % for operation on Ravensview biogas.

Graduate

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Thurgood, Chris, Peppley, Brant A..

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The effect of cadmium (Cd) bioavailability on phytoextraction feasibility and ecological risk was investigated in soil amended with municipal solid waste (MSW) and sewage sludge (SS) compost at the Peterborough Gun Club in Peterborough, Canada. Plant uptake was low due to sorption of Cd to stable soil fractions, and it was therefore determined that phytoextraction was not a feasible method of remediating these MSW/SS compost-based soils. Low plant bioavailability limited exposure of higher order receptors to Cd, and an ecological risk assessment (ERA) indicated no potential for risk to any of the seven ecological receptors evaluated at this site. For comparison, risk was also characterized at a nearby PCB-contaminated site using the same seven receptors. Previous research had shown that phytoextraction would be an effective method of remediating this PCB site due to high plant uptake of the contaminant, and an ERA revealed that five of the seven receptors evaluated were potentially at risk of experiencing adverse health effects from PCBs. As ERAs characterize risk under present environmental conditions, the long-term potential for biochar to sorb Cd and limit its bioavailability was evaluated at the Peterborough site. Trends indicated decreasing Cd bioavailability in biochar-amended soil relative to the un-amended control, and this coincided with a significant decrease in organic matter content in the control soil. The results of this thesis emphasize the influence of contaminant bioavailability on phytoextraction feasibility and ecological risk, and demonstrate the potential for biochar to limit long-term Cd bioavailability and risk in MSW/SS compost-amended soil.

L'effet de la biodisponibilité de cadmium (Cd) sur la faisabilité d’utiliser la phytoextraction ainsi que les risques écologiques associés ont été étudiés dans les sols ou des déchets municipaux solides (DMS) et des boues d'épuration (BE) compostées ont été ajoutés au Club de Tir Peterborough (CTP) à Peterborough, Canada. La phytoextraction de Cd par les plantes était faible grâce à la sorption de Cd sur les fractions de sol stables et la phytoextraction par les plantes n'est donc pas une méthode possible pour rétablir les sols contaminés avec le Cd par l'application de compost produit avec DMS/BE. Cependant, la faible phytoextraction de Cd par les plantes réduit l’exposition du Cd pour les récepteurs écologiques des niveaux trophiques plus élevés sur ce site, et une évaluation des risques écologiques a indiqué qu’il n’y a aucun potentiel de risque. Pour comparaison, les risques écologiques ont aussi été caractérisés sur un site contaminé par des biphényles polychlorés (BPC) en utilisant les mêmes sept récepteurs. Des recherches antérieures avaient montré que la phytoextraction serait une méthode efficace de réhabiliter ce site à cause de la biodisponibilité des BPC élevée, et une évaluation des risques écologiques a indiqué qu'il existe le potentiel de risque à cinq des sept récepteurs évaluées. Étant donné que les évaluations des risques écologiques…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Zeeb, Barbara, A., Rutter, Allison.

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Ferritin is an important iron chelating protein that is reported to store iron in order to prevent the toxic effects of excess iron inside the cell. Ferritin is found almost ubiquitously in all kingdoms of life except in Fungi where its homologues in different fungal species are very limited. We previously conducted a genetic screen looking for sequences with the ability to suppress the pro-apoptotic effects of Bax in yeast. One of the DNA sequences we found that prevented Bax-mediated cell death in Saccharomyces cerevisiae yeast cells was that of the human ferritin heavy chain subunit (H-ferritin). As ferritins appear to be absent in yeast, it was surprising to find that human ferritin was able to function in yeast to prevent the effects of Bax. We therefore set out to determine whether yeast in fact does have a ferritin homologue by conducting a search in the Saccharomyces Genome Database (SGD) for sequences homologous to human H-ferritin. We identified YER067W, a 161 residue protein with 20% sequence identity with the 183 residue human H-ferritin as a likely ferritin yeast homologue. Like human H-ferritin, we found YER067W to be a Bax suppressor and general pro-survival protein. When overexpressed in S. cerevisiae separately, both proteins were found to behave similarly under various conditions, and were found to behave like iron scavengers as opposed to iron storage centres in yeast. Overall, these results suggest that YER067W is likely to be the long sought-after yeast ferritin (yFer1).

La ferritine est une protéine importante qui chélate et entrepose le fer afin d'éviter les effets toxiques de l'excès de fer dans la cellule. La ferritine se trouve presque ubiquitaire dans tous les règnes de la vie, sauf dans les champignons où ses homologues dans des différentes espèces fongiques sont rares. Nous avons déjà effectué un criblage à la recherche de séquences avec la possibilité de bloquer les effets pro-apoptotiques de Bax. Une des séquences d'ADN que nous avons trouvé qui a empêché la mort cellulaire induite par Bax dans des cellules de levure Saccharomyces cerevisiae a été celle qui code pour la chaîne lourde de la ferritine humaine (H-ferritine). Parce que la levure n'est pas connue pour posséder des ferritines, il était surprenant de trouver que la ferritine humaine était en mesure de fonctionner dans la levure pour prévenir les effets de Bax. Nous avons donc cherché à déterminer si la levure, en fait, a un homologue de ferritine en effectuant une recherche dans la base de données du génome de Saccharomyces (SGD) pour des séquences qui sont homologues à l’H-ferritine humaine. Nous avons identifié YER067W, une protéine de 161 résidus avec 20% d'identité de séquence avec l’H-ferritine humaine de 183 résidus comme un homologue de levure susceptible d’être la ferritine. Comme pour la H-ferritine humaine, nous avons trouvé que YER067W est un suppresseur de Bax et une protéine pro-survie générale. Lorsque surexprimée dans S. cerevisiae séparément, les deux protéines se comportent de façon similaire dans des…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Greenwood, Michael.

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Phytoextraction is a potential remediation technique for low to moderate levels of dichlorodiphenyltrichloroethane (DDT)-contaminated soil. Identification of new species as phytoextractors of DDT is a vital step in establishing phytoextraction as a commercially-viable and environmental-friendly remediation technique. Thirteen of native and naturalized weed species were investigated both in field and greenhouse studies using DDT-contaminated soil from Point Pelee National Park (PPNP), ON, Canada. A screening study established the extraction capabilities of nine wild growing species and determined that four of these Trifolium pratense, Symphyotrichum novae-angliae, Solanum ptycanthum Dun. Verbascum thapsus have a higher DDT extraction potential than the known DDT phytoextractor Cucurbita. pepo ssp. pepo cv. Howden assuming plants are grown at optimal densities. A subsequent field trial was conducted using three native weed species and C. pepo at PPNP in low (291 ng/g), moderate (5083 ng/g) and high (10192 ng/g) DDT-contaminated sites. This study determined that two native species i.e. Schizachyrium scoparium and Panicum virgatum had higher shoot DDT extractions than C. pepo at the high DDT-contaminated site. An interesting and unique finding was that, DDT uptake of C. pepo is concentration dependent with a maximum uptake observed at a threshold soil DDT ~5000 ng/g. In contrast, such threshold soil DDT concentration was absent for weed species where uptake increases linearly with increasing soil DDT concentration. A final greenhouse study using four perennial native and naturalized weed species in low (2300 ng/g) and high (17500 ng/g) DDT-contaminated soils collected from PPNP, further demonstrated that weed species are capable of significant DDT phytoextraction Trifolium pratense in both low and high DDT-contaminated soil regardless of growing conditions exceeded C. pepo extraction by considering optimum planting density. Hence, it can be summarized that native (or naturalized) weed species show significant potential/prospect as phytoextractors of DDT, especially at ecologically sensitive sites where it is important to minimize habitat disturbance. It is noted that this is the first comprehensive study of DDT phytoextraction using of native weed species.

La phytoextraction est une technique pouvant remédier les sols contaminés avec des niveaux faibles à modérés de dichlorodiphenyltrichloroéthane (DDT). L’identification de nouvelles espèces ayant la capacité de phytoextraire le DDT est une étape essentielle dans l'établissement de la phytoextraction comme technique de remédiation commercialement viable et respectueuse de l'environnement. Treize espèces d’herbes indigènes et naturalisées ont été étudiées dans des essais in-situ et dans une serre avec des sols contaminés au DDT provenant du parc national de la Pointe-Pelée (PNPP), ON, Canada. Une évaluation préalable a permis de déterminer les capacités d'extraction de neuf espèces sauvages et a démontré que quatre de ces espèces, Trifolium pratense, Symphyotrichum…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Prof. Barbara, Zeeb, Dr. Allison, Rutter.

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This thesis comprises two principal areas of research: new derivations of asymptotic results in renewal theory and the computation of the distribution for the number of renewals with bulk arrivals. A simple and elegant solution to determine the asymptotic results for the renewal density as well as for the first and second moments of the number of renewals for the discrete-time renewal process is presented. Using generating functions, the difficult-to-determine constant term in the second moment is also addressed. A similar process using Laplace transforms (LTs) is likewise employed to determine analogous results in continuous time. Further, the solution is extended to determine the asymptotic results for the first and second moments of the number of bulk renewals as well. The distribution of the number of renewals for both single and bulk arrivals in continuous time is calculated using an algorithm employed through MAPLE. These numerical results are acquired by considering rational as well as non-rational LTs and Padé-approximated LTs for the distributions of inter-renewal times. The asymptotic results derived in the first part of this thesis then help to validate the accuracy of these numerical results.

Cette thèse comprend deux domaines de recherche principaux: de nouvelles dérivations de résultats asymptotiques pour la théorie du renouvellement, et le calcul de la distribution pour le nombre de renouvellements pour les arrivées en groupes. Une solution simple et élégante pour déterminer les résultats asymptotiques pour la densité de renouvellement ainsi que pour les premiers et deuxièmes moments du nombre de renouvellements pour le processus de renouvellement en temps discret est présentée. En utilisant des fonctions génératrices, le terme constant qui est difficile à déterminer pour le second moment est également résolu. Un processus similaire utilisant les transformations de Laplace (LTs) est également utilisé pour déterminer des résultats similaires en temps continu. De plus, la solution est poursuivie afin de déterminer les résultats asymptotiques pour les premiers et deuxièmes moments du nombre de renouvellements en groupes. La distribution du nombre de renouvellements pour les arrivées simples et en groupes en temps continu est calculée en utilisant un algorithme fait avec MAPLE. Ces résultats numériques sont acquis en considérant les LTs rationnelles et non-rationnelles ainsi que les LTs de Padé pour les distributions des intervalles de renouvellement. Les résultats asymptotiques dérivés dans la première partie de cette thèse aident ensuite à valider le calcul d’incertitude de ces résultats numériques.

Graduate

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Chaudhry, Mohan.

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Strontium-90 (90Sr) is an anthropogenic contaminant that is present in the environment from spent nuclear fuel, radioactive waste, and atmospheric fallout from nuclear weapon tests and major nuclear incidents. Strontium-90 is one of the most hazardous and radiotoxic radioisotopes, due to its relative long half-life and high mobility in the environment. Because of its significant health hazards, 90Sr needs to be measured accurately. The radioanalytical capabilities for the determination of 90Sr in the environment are challenged by matrix interferences, which often result in less effective, long, and tedious determination methods. Moreover, a number of shortcomings were found in the current seawater 90Sr methods following the Fukushima Daiichi nuclear power accident in March 2011. Thus, the need for effective, rapid, and simple procedures is on-going. In the present dissertation, the advancements in modern technologies were used to minimize some of the gaps in current radioanalytical capabilities used for the determination of 90Sr in water. The present work considered techniques at moderate and low levels of detection, and in each case undertook to produce methodologies with increased speed of analysis and greater efficiency. A triple-to-double coincidence ratio (TDCR) Čerenkov counting technique using a Hidex liquid scintillation counter was developed for the indirect determination of 90Sr from 90Y at equilibrium activity concentrations of 90Sr-90Y. The technique was fast and simple with excellent performance test results. For low level 90Sr determination in water, pre-concentration using semi-selective co-precipitation and highly selective extraction chromatography techniques were used. Freshwater 90Sr was determined directly as well as indirectly from 90Sr-90Y equilibrium activity concentrations. The method employed (1) co-precipitation of freshwater 90Sr-90Y using calcium phosphate in alkaline conditions; (2) sequential purification of 90Sr and 90Y on Sr-Resin® and DGA-N® extraction chromatography columns, respectively; and (3) detection of 90Sr by liquid scintillation assay (LSA) at two different time intervals and that of 90Y using both Čerenkov counting and LSA. Seawater 90Sr was determined indirectly from 90Y at equilibrium activity concentrations of 90Sr-90Y. The method used (1) co-precipitation of seawater 90Y using calcium carbonate and hydrous titanium oxide in alkaline conditions; (2) purification of 90Y on DGA-N® resin; and (3) detection of 90Y using both Čerenkov counting and LSA. The methods’ performance evaluation demonstrated excellent agreement between measured and expected activities of spiked 90Sr-90Y standard solution. Effective implementation of the freshwater method on natural water samples containing a wide range of 90Sr-90Y concentrations was also achieved.

Le strontium-90 (90Sr) est un contaminant anthropogénique présent dans l’environnement et provenant de combustible nucléaire usé, de déchets radioactifs, et de retombées atmosphériques des essais d’armements nucléaires et des…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Kelly, David, Corcoran, Emily, Xiongxin, Dai.

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Special nuclear materials (SNMs) are those which contain 233U, 235U and 239Pu. They are safeguarded by the International Atomic Energy Agency (IAEA) in addition to individual governmental organisations. Nuclear forensic analysis (NFA) is concerned with the characterisation and attribution of illicit nuclear materials, especially uranium and plutonium. Physical, chemical, and isotopic characteristics are determined with instrumentation that is ideally rapid, non-destructive, and sensitive. Delayed neutron and gamma emissions from fissioned isotopes have signature yields, energies, and temporal behaviour, their measurement allows the rapid characterisation of SNM content in a variety of matrices. Previous work developed a delayed neutron counting (DNC) prototype at the Royal Military College of Canada (RMCC). This system sent samples containing 235U content to a SLOWPOKE-2 reactor where they underwent fission. Samples were then sent via pneumatic transfer to the counting arrangement, containing six helium-3 detectors, which recorded the delayed neutron emissions. This undertaking began with the attribution of the time-dependent neutron background present in the SLOWPOKE-2 site used for DNC irradiations; the contribution of this uranium contamination was lowered from a mass equivalent of 120 to 50 ng per vial. Subsequent delayed neutron measurements of samples containing mixtures of 233U and 235U were used to determine their relative ratios (in %) with an average absolute error of ± 4 %. This thesis also included the development of a Delayed Neutron and Gamma Counting (DNGC) system intended to contribute to nuclear forensics instrumentation available to the Canadian Department of National Defence. The delayed gammas emitted from SNM were used in complement with delayed neutron measurements in an example which detected, identified, and quantified 233U content with an average relative error and accuracy of -2.2 and 1.5 %, respectively. Throughout system development detailed measurements of both delayed neutron and delayed gammas from microgram quantities of 233U, 235U, and 239Pu were performed. These were used for comparison to the simulations of delayed particle emissions and detection from the Monte Carlo code MCNP6, in collaboration with Los Alamos National Laboratory. One of the options available in MCNP6 for delayed neutron emissions was found to be discrepant with measurements ≥ 100 s after fission. These DN comparisons were released as a MCNP6 test suite to all users; the most recent release of MCNP6.1.1β resolves many of the observed discrepancies found by this work. MCNP6 simulations were also used to predict expected delayed gamma signatures useful for NFA, and compared to DNGC system measurements in a final study.

Les matériaux nucléaires spéciaux (MNS) sont ceux qui contiennent les isotopes 233U, 235U et 239Pu. Ils sont réglementés par l’Agence Internationale de l’Énergie Atomique (AIEA) en plus des organisations gouvernementales individuelles. L’analyse nucléaire légale (ANL) se préoccupe de la…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Kelly, David, Corcoran, Emily.

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Nuclear forensic analysis is a modern science that uses numerous analytical techniques to identify and attribute nuclear materials in the event of a nuclear explosion, radiological terrorist attack or the interception of illicit nuclear material smuggling. The Canadian Department of National Defence has participated in recent international exercises that have highlighted the Nation’s requirement to develop nuclear forensics expertise, protocol and capabilities, specifically pertaining to the analysis of special nuclear materials (SNM). A delayed neutron counting (DNC) system has been designed and established at the Royal Military College of Canada (RMC) to enhance the Government’s SNM analysis capabilities. This analytical technique complements those already at RMC by providing a rapid and non-destructive method for the analysis of the fissile isotopes of both uranium (U) and plutonium (Pu). The SLOWPOKE-2 reactor at RMC produces a predominately thermal neutron flux. These neutrons induce fission in the SNM isotopes 233U, 235U and 239Pu releasing prompt fast neutrons, energy and radioactive fission fragments. Some of these fission fragments undergo β- decay and subsequently emit neutrons, which can be recorded by an array of sensitive 3He detectors. The significant time period between the fission process and the release of these neutrons results in their identification as ‘delayed neutrons’. The recorded neutron spectrum varies with time and the count rate curve is unique to each fissile isotope. In-house software, developed by this project, can analyze this delayed neutron curve and provides the fissile mass in the sample. Extensive characterization of the DNC system has been performed with natural U samples with 235U content ranging from 2 – 7 μg. The system efficiency and dead time behaviour determined by the natural uranium sample analyses were validated by depleted uranium samples with similar quantities of 235U resulting in a typical relative error of 3.6%. The system has accurately determined 235U content over three orders of magnitude with 235U amounts as low as 10 ng. The results have also been proven to be independent of small variations in total analyte volume and geometry, indicating that it is an ideal technique for the analysis of samples containing SNM in a variety of different matrices. The Analytical Sciences Group at RMC plans to continue DNC system development to include 233U and 239Pu analysis and mixtures of SNM isotopes.

L’analyse nucléaire légale est une science moderne qui utilise plusieurs techniques d’analyse pour identifier et attribuer des matériaux nucléaires dans le cas d’explosion nucléaire, d’attaque terroriste radiologique ou de la découverte de contrebande illicite de matériaux nucléaires. Le Ministère de la défense nationale du Canada a participé récemment à des exercices internationaux qui ont mis en lumière le besoin de notre pays de développer le savoir-faire en analyse nucléaire légale, ainsi que les protocoles et les capacités, plus spécifiquement pertinents à l’analyse…

Advisors/Committee Members: Royal Military College of Canada / Collège militaire royal du Canada, Kelly, David, Corcoran, Emily.