<p> Exposure to traffic-related air pollutants has been found to be damaging to human health. Nitrogen dioxide (NO2) levels, commonly used to indicate traffic-related pollution levels, vary significantly over small areas with higher levels found near sources such as major roads and industrial areas. The temporal and spatial variability in NO2 levels is partly caused by fluctuations in meteorological variables, and better understanding of these: meteorological influences can be used to enhance exposure assessment in health effects models.</p> <p> In this study, the interaction between measured hourly NO2 concentrations and climate variables at 11 locations in the Toronto-Hamilton Urban Airshed (THUAS) is examined. Analysis of meteorological data shows that two large urban heat islands (UHI) are present in the THUAS, centred on the downtown areas of Toronto and Hamilton. Lake breezes are found to occur frequently in the region, on up to 50% of summer days at lakeshore locations. These temperature and wind patterns influence NO2 and pollutant distributions. NO2 concentrations are highest in the early morning and late evening. Mean concentrations are highest in winter, although individual 1-hour NO2 concentrations are found to be highest in summer because of higher production rates. Wind direction is the strongest control on hourly NO2 concentration, and temperature and wind speed also have an effect. Seasonal variations in meteorology and emissions mean that the degree of spatial variability in NO2 concentrations changes from season-to-season in the THUAS resulting in variable exposure of urban populations.</p> <p> An attempt to improve an existing Land Use Regression (LUR) model, used for predicting nitrogen dioxide (NO2) concentrations and estimating human exposure, was made by incorporating high resolution interpolated observed up- and downwind effects of wind transport on NO2 concentrations around major roadways. Incorporation of observed wind direction effects in the LUR model slightly improved the accuracy of NO2 concentration estimates in densely populated, high traffic, and industrial/business areas in both Toronto and Hamilton. However the short-term nature of initial NO2 concentration data limits the utility of the model in light of the significant seasonal variation in climate parameters in the THUAS and their influence on NO2 transport and distribution.</p> / Thesis / Master of Science (MSc)

The reparametization of semiempirical Hamiltonians is an emerging method used in direct dynamics studies. The use of semiempirical Hamiltonians in direct dynamics studies diminishes the computational cost of trajectory calculations and negates the need for an analytical potential energy surface when performing reaction dynamics studies. The reparametization of semiempirical Hamiltonians increases the agreement with experiment and high level ab initio theory. We have chosen to create one set of new parameters that apply to two related reactions, F + CH₄ → HF + CH₃ and F + C₂H₆ → HF + C₂H₅. We have performed an electronic structure study for these reactions. The ab initio data obtained from the electronic structure study is then used as the reference for a reparametization of the PM3 Hamiltonian. The reparametization has improved the ab initio and PM3 reaction energy and potential energy surface scan agreement. This new set of parameters for PM3 (SRP-PM3) is used to perform a direct quasiclassical trajectory study of the reactions. The vibrational and rotational HF distributions calculated using SRP-PM3 are compared with experiments. We have observed an improvement in the agreement with experimental vibrational distributions but have seen no change in the rotational distributions. / Master of Science

This dissertation analyzes the major role that Alexander Hamilton's ideas and innovations played in the development of the American administrative state during and subsequent to the Federalist era. Secondly, it contrasts the richness of Hamilton's prudential theory of public administration with the sterile scientific theories of administration advanced in the twentieth century. Though modern American public administration is usually thought of as a product of the early twentieth-century reform era, many ideas articulated during the founding period were ingrained in our legal, political, and administrative thought. Of those founding ideas, Hamilton's are the most numerous and significant. Hamilton's administrative thought and innovations are traced in the historical development of the American administrative state in terms of three topics central to public administrative development. These are finance, military/foreign affairs, and the nature of public office. The final chapter summarizes Hamilton's contributions and then challenges our acceptance of Woodrow Wilson as founder of American public administrative thought. Alexander Hamilton is far more appropriate as founder of both the thought and practice of American public administration. / Ph. D.

L'objectif de cette thèse est de développer la théorie du contrôle stochastique et ses applications en dynamique des populations. D'un point de vue théorique, nous présentons l'étude de problèmes de contrôle stochastique à horizon fini sur des processus de diffusion, de branchement non linéaire et de branchement-diffusion. Dans chacun des cas, nous raisonnons par la méthode de la programmation dynamique en veillant à démontrer soigneusement un argument de conditionnement analogue à la propriété de Markov forte pour les processus contrôlés. Le principe de la programmation dynamique nous permet alors de prouver que la fonction valeur est solution (régulière ou de viscosité) de l'équation de Hamilton-Jacobi-Bellman correspondante. Dans le cas régulier, nous identifions également un contrôle optimal markovien par un théorème de vérification. Du point de vue des applications, nous nous intéressons à la modélisation mathématique du cancer et de ses stratégies thérapeutiques. Plus précisément, nous construisons un modèle hybride de croissance de tumeur qui rend compte du rôle fondamental de l'acidité dans l'évolution de la maladie. Les cibles de la thérapie apparaissent explicitement comme paramètres du modèle afin de pouvoir l'utiliser comme support d'évaluation de stratégies thérapeutiques. / The main objective of this thesis is to develop stochastic control theory and applications to population dynamics. From a theoritical point of view, we study finite horizon stochastic control problems on diffusion processes, nonlinear branching processes and branching diffusion processes. In each case we establish a dynamic programmic principle by carefully proving a conditioning argument similar to the strong Markov property for controlled processes. Then we deduce that the value function is a (viscosity or regular) solution of the associated Hamilton-Jacobi-Bellman equation. In the regular case, we further identify an optimal control in the class of markovian strategies thanks to a verification theorem. From a pratical point of view, we are interested in mathematical modelling of cancer growth and treatment. More precisely, we build a hybrid model of tumor growth taking into account the essential role of acidity. Therapeutic targets appear explicitly as model parameters in order to be able to evaluate treatment strategies.

La simulation numérique est indissociable du calcul haute performance. Ces vingt dernières années,l'informatique a connu l'émergence d'architectures parallèles multi-niveaux. Exploiter efficacement lapuissance de calcul de ces machines peut s'avérer être une tâche délicate et requérir une expertise à la foistechnologique sur des notions avancées de parallélisme ainsi que scientifique de part la nature même desproblèmes traités.Le travail de cette thèse est pluri-disciplinaire s'appuyant sur la conception d'une librairie de calculparallèle réutilisable pour la résolution des équations Hamilton-Jacobi-Bellman. Ces équations peuventse retrouver dans des domaines diverses et variés tels qu'en biomédical, géophysique, ou encore robotiqueen l'occurence sur les applications de planification de mouvement et de reconstruction de formestri-dimensionnelles à partir d'images bi-dimensionnelles. Nous montrons que les principaux algorithmesnumériques amenant a résoudre ces équations telles que les méthodes de type fast marching, ne sont pasappropriés pour être efficaces dans un contexte parallèle. Nous proposons la méthode buffered fast iterativequi permet d'obtenir une scalabilité parallèle non obtenue jusqu'alors. Un des points sensibles relevésdans cette thèse est de parvenir à trouver une recette de compromis entre abstraction, performance etmaintenabilité afin de garantir non seulement une réutilisabilitédans le sens classique du domaine de génielogiciel mais également en terme de réutilisabilité séquentielle/parallèle / Numerical simulation is strongly bound with high performance computing. Programming scientificsoftwares requires at the same time good knowledge on the mathematical numerical models and alsoon the techniques to make them efficient on today's computers. Indeed, these last twenty years, wehave experienced the rising of multi-level parallel architectures. The work in this thesis dissertation ismultidisciplinary by designing a reusable parallel numerical library for solving Hamilton-Jacobi-Bellmanequations. Such equations are involved in various fields such as in biomedical, geophysics or robotics. Inparticular, we will show interests in path planning and shape from shading applications. We show thatthe methods to solve these equations such as the widely used fast marching method, are not designedto be used effciently in a parallel context. We propose a buffered fast iterative method which givesan interesting parallel scalability. This dissertation takes interest in the challenge to find compromisesbetween abstraction, performance and maintainability in order to combine both software reusability andalso sequential/parallel reusability. We propose code abstraction allowing algorithmic and data genericitywhile trying to keep a maintainable and performant code potentially parallelizable

[pt] A Revolução Americana registrou uma intensa participação política popular nos Estados da Confederação. Este período marcou a preferência pela doutrina da separação absoluta de Poderes, uma vez que o sistema de governo balanceado inglês permitiu que o clientelismo real corrompesse a independência do Parlamento, órgão supostamente responsável pela defesa das liberdades civis nas colônias. Porém, o engajamento do povo foi condenado pela elite norteamericana, que liderou um movimento de centralização do poder capaz de controlar o excesso de democracia local, identificado com a supremacia que as assembléias possuíam no âmbito estadual. Neste contexto surge a Constituição de 1787, que funda suas bases na teoria dos freios e contrapesos como um método de fiscalização recíproca dos Poderes, mas, com especial destaque, para o controle do Legislativo. O evento constitucional enfraqueceu a virtude dos cidadãos, que se restringiu à atividade de expansão rumo à fronteira e criou um mecanismo de governo autônomo, que concentrou a política na ação de uma elite dirigente e na relação entre os diferentes órgãos intra-estatais. O estudo da concepção de separação de Poderes em Jefferson, Madison e Hamilton ajuda a esclarecer o modo com que o projeto constitucional de 1787 rompeu com a ideologia a essência revolucionária. / [en] The American Revolution presented a high level of popular politics participation under the Confederation years. This moment marked the option for the absolute doctrine of the separation of powers as a response against the failure of the balanced constitution theory and the incapacity of the British Parliament to protect the colonies civil liberties. However, the fear of popular engagement made the American elites lead a centralization of power that could be able to control the popular local democracy. The Constitution of the United States and its checks and balances system were born as a result of that conservative process. The constitutional structure protected the government of the people direct action and influence, creating a separated dimension to the politics forces game. The study of the concepts of this era and the meanings they were used, particularly, the Jefferson s, Madison s and Hamilton s conception concerning of the separation of powers doctrine helps to understand how the Constitution ruptured the spirit of the American Revolution, based on the active citizenship.

Aldo Crommelynck (1931-2008) a animé l'atelier Crommelynck à Paris de 1956 à 1986, en compagnie de son frère Piero, puis a travaillé seul entre Paris et New York en partenariat avec Pace Editions, jusqu'en 1998. Sa collaboration avec les peintres modernes, dont Picasso à Mougins, a inauguré une carrière internationale auprès d'une quarantaine d'artistes contemporains. Sa maîtrise de l'eau-forte s'est intégrée au milieu artistique international, entre Paris, Londres et New York, dans un contexte profitable au marché de l'art. Son nom est associé à un mouvement de retour à la taille­douce qui coïncide avec le goût des artistes issus du Pop pour le travail de la main et pour la figuration du quotidien. D'autres, issus du minimalisme et du néo-expressionnisme, verront en lui le dépositaire d'un certain métier de la gravure identifié à Paris. Cette thèse entend déterminer ce que fut le «style Crommelynck», dans toutes ses dimensions. / Aldo Crommelynck (1931-2008) run the Crommelynck studio, in Paris from 1956 to 1986, with his brother Piero, and then worked alone between Paris and New York in partnership with Pace Editions until 1998. His collaboration with modem painters, including Picasso in Mougins, preceded his international career with forty or so contemporary artists. His mastery of etching well integrated into the artistic world of Paris, London and New York, in a context profitable to the art market. His name is associated with the revival of printmaking in the United States that coincided with the taste of the artists coming from Pop Art for handmade creation and for the representation of daily life. Others, who came afterwards, impregnated with Minimalism or Neo-expressionism, saw him as the repository of a certain etching craft identified with Paris. This thesis intends to determine what was the « Crommerlynck style » in all its dimensions.

Cette thèse étudie des modèles mathématiques inspirés par la biologie. Plus précisément, nous nous concentrons sur des équations aux dérivées partielles cinétiques. Les champs d'application des équations cinétiques sont nombreux mais nous nous concentrons ici sur des phénomènes de propagation d'espèces invasives, notamment la bactérie Escherichia coli et le crapaud buffle Rhinella marina.La première partie de la thèse ne présente pas de résultats mathématiques. Nous construisons plusieurs modélisations pour la dispersion à grande échelle du crapaud buffle en Australie. Nous confrontons ces mêmes modèles à des données statistiques multiples (taux de fécondité, taux de survie, comportements dispersifs) pour mesurer leur pertinence. Ces modèles font intervenir des processus à sauts de vitesses et des équations cinétiques.Dans la seconde partie, nous étudions des phénomènes de propagation dans des modèles cinétiques plus simples. Nous illustrons plusieurs méthodes pour établir mathématiquement des formules de vitesse de propagation dans ces modèles. Cette partie nous amène à établir des résultats de convergence d'équations cinétiques vers des équations de Hamilton-Jacobi par la méthode de la fonction test perturbée. Nous montrons également comment le formalisme Hamilton-Jacobi permet de trouver des résultats de propagation et enfin, nous construisons des solutions en ondes progressives pour un modèle de transport-réaction. Dans la dernière partie, nous établissons un résultat de limite de diffusion stochastique pour une équation cinétique aléatoire. Pour ce faire, nous adaptons la méthode de la fonction test perturbée sur la formulation d'une EDP stochastique en terme de générateurs infinitésimaux.La thèse comporte également une annexe qui expose les données trajectorielles des crapauds dont nous nous servons en première partie." / In this thesis, we study some biology inspired mathematical models. More precisely, we focus on kinetic partial differential equations. The fields of application of such equations are numerous but we focus here on propagation phenomena for invasive species, the Escherichia coli bacterium and the cane toad Rhinella marina, for example. The first part of this this does not establish any mathematical result. We build several models for the dispersion of the cane toad in Australia. We confront those very models to multiple statistical data (birth rate, survival rate, dispersal behaviors) to test their validity. Those models are based on velocity-jump processes and kinetic equations. In the second part, we study propagation phenomena on simpler kinetic models. We illustrate several methods to mathematically establish propagation speed in this models. This part leads us to establish convergence results of kinetic equations to Hamilton-Jacobi equations by the perturbed test function method. We also show how to use the Hamilton-Jacobi framework to establish spreading results et finally, we build travelling wave solutions for reaction-transport model. In the last part, we establish a stochastic diffusion limit result for a kinetic equation with a random term. To do so, we adapt the perturbed test function method on the formulation of a stochastic PDE in term of infinitesimal generators. The thesis also contains an annex which presents the data on toads’ trajectories used in the first part."

Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-09-04T13:42:58Z No. of bitstreams: 1 Watson Robert.pdf: 2699368 bytes, checksum: cf204eec3df50b251f4adbbbd380ffd0 (MD5) / Made available in DSpace on 2017-09-04T13:42:58Z (GMT). No. of bitstreams: 1 Watson Robert.pdf: 2699368 bytes, checksum: cf204eec3df50b251f4adbbbd380ffd0 (MD5) Previous issue date: 2014-08-21 / Due to the demand for high-performance equipments and the rising cost of energy, the industrial sector is developing equipments to attend minimization of the theirs operational costs. The implementation of these requirements generate a demand for projects and implementations of high-performance control systems. The optimal control theory is an alternative to solve this problem, because in its design considers the normative specifications of the system design, as well as those that are related to the operational costs. Motivated by these perspectives, it is presented the study of methods and the development of algorithms to the approximated solution of the Equation Hamilton-Jacobi-Bellman, in the form of discrete Riccati equation, model free and dependent of the dynamic system. The proposed solutions are developed in the context of adaptive dynamic programming that are based on the methods for online design of optimal control systems, Discrete Linear Quadratic Regulator type. The proposed approach is evaluated in multivariable models of the dynamic systems to evaluate the perspectives of the optimal control law for online implementations. / Devido a demanda por equipamentos de alto desempenho e o custo crescente da energia, o setor industrial desenvolve equipamentos que atendem a minimização dos seus custos operacionais. A implantação destas exigências geram uma demanda por projetos e implementações de sistemas de controle de alto desempenho. A teoria de controle ótimo é uma alternativa para solucionar este problema, porque considera no seu projeto as especificações normativas de projeto do sistema, como também as relativas aos seus custos operacionais. Motivado por estas perspectivas, apresenta-se o estudo de métodos e o desenvolvimento de algoritmos para solução aproximada da Equação Hamilton-Jacobi-Bellman, do tipo Equação Discreta de Riccati, livre e dependente de modelo do sistema dinâmico. As soluções propostas são desenvolvidas no contexto de programação dinâmica adaptativa (ADP) que baseiam-se nos métodos para o projeto on-line de Controladores Ótimos, do tipo Regulador Linear Quadrático Discreto. A abordagem proposta é avaliada em modelos de sistemas dinâmicos multivariáveis, tendo em vista a implementação on-line de leis de controle ótimo.

Έστω $V$ ένα σύνολο $n$ κορυφών και έστω ${\cal M}$ ένα πεπερασμένα αριθμήσιμο σύνολο $m$ ετικετών. Ένα γράφημα ετικετών προκύπτει αν αντιστοιχήσουμε σε κάθε κορυφή $v \in V$ ένα υποσύνολο $S_v$ του ${\cal M}$ και στη συνέχεια ενώσουμε όποιες κορυφές έχουν κοινά στοιχεία στα αντίστοιχα σύνολα ετικετών τους. Η παρούσα διδακτορική διατριβή ασχολείται με την εξέταση συνδυαστικών ιδιοτήτων και το σχεδιασμό και ανάλυση αλγορίθμων που σχετίζονται με δυο μοντέλα τυχαίων γραφημάτων που προκύπτουν από την επιλογή των συνόλων $S_v$ με βάση συγκεκριμένες κατανομές. Το πρώτο από αυτά τα μοντέλα ονομάζεται \emph{Μοντέλο Τυχαίων Γραφηματων Τομής Ετικετών} ${\cal G}_{n, m, p}$ (\textlatin{random intersection graphs model}) και κάθε σύνολο ετικετών $S_v$ διαμορφώνεται επιλέγοντας ανεξάρτητα κάθε ετικέτα με πιθανότητα $p$. Το δεύτερο μοντέλο ονομάζεται \emph{Ομοιόμορφο Μοντέλο Τυχαίων Γραφηματων Τομής Ετικετών} ${\cal G}_{n, m, \lambda}$ (\textlatin{uniform random intersection graphs model}) και κάθε σύνολο ετικετών $S_v$ επιλέγεται (ανεξάρτητα για κάθε κορυφή) ισοπίθανα ανάμεσα σε όλα τα υποσύνολα του ${\cal M}$ μεγέθους $\lambda$. Τα μοντέλα αυτά μπορούν να χρησιμοποιηθούν για να μοντελοποιήσουν καταστάσεις που αφορούν θέματα ασφάλειας σε δίκτυα αισθητήρων, αλλά και για την αναπαράσταση των συγκρούσεων (\textlatin{conflicts}) που δημιουργούνται σε περιπτώσεις διαμοιρασμού πόρων. Ακόμα, μπορούν να χρησιμοποιηθούν για τη μοντελοποίηση κοινωνικών γραφημάτων (\textlatin{social graphs}) στα οποία δυο οντότητες συνδέονται όταν έχουν κάποιο κοινό χαρακτηριστικό. Στο Μοντέλο Τυχαίων Γραφηματων Τομής Ετικετών ${\cal G}_{n, m, p}$ μελετάμε καταρχήν το πρόβλημα της ύπαρξης κύκλων \textlatin{Hamilton}. Συγκεκριμένα, αποδεικνύουμε ένα άνω φράγμα για την πιθανότητα επιλογής ετικετών $p$ έτσι ώστε κάθε στιγμιότυπο του ${\cal G}_{n, m, p}$ να περιέχει ένα κύκλο \textlatin{Hamilton} με πιθανότητα που τείνει στο 1 καθώς το $n$ τείνει στο άπειρο. Ακόμα, αναλύουμε δυο πιθανοτικούς αλγορίθμους που, για ορισμένες τιμές των παραμέτρων $m, p$ του μοντέλου, καταφέρνουν να κατασκευάσουν ένα κύκλο \textlatin{Hamilton} με πιθανότητα που τείνει στο 1, δηλαδή σχεδόν πάντα. Επίσης, δείχνουμε ότι σχεδόν κάθε στιγμιότυπο του ${\cal G}_{n, m, p}$ έχει καλή επεκτασιμότητα (\textlatin{expansion}), ακόμα και για $p$ πολύ κοντά στο κατώφλι συνεκτικότητας του μοντέλου. Στη συνέχεια, δίνουμε βέλτιστα άνω φράγματα (που ισχύουν με πιθανότητα που τείνει στο 1 σε ένα ευρύ πεδίο τιμών των παραμέτρων του μοντέλου) για σημαντικές ποσότητες που αφορούν τυχαίους περιπάτους σ ε στιγμιότυπα του ${\cal G}_{n, m, p}$ όπως ο χρόνος μίξης (\textlatin{mixing time}) και ο χρόνος κάλυψης (\textlatin{cover time}). Στο Ομοιόμορφο Μοντέλο Τυχαίων Γραφηματων Τομής Ετικετών ${\cal G}_{n, m, \lambda}$ μελετάμε την ύπαρξη κύκλων \textlatin{Hamilton} σε ένα ορισμένο πεδίο τιμών των παραμέτρων $m, \lambda$ του μοντέλου. Τέλος, υπολογίζουμε με τη βοήθεια της Πιθανοτικής Μεθόδου το κατώφλι ύπαρξης ανεξάρτητων συνόλων κορυφών. / Let $V$ be a set of $i$ vertices and let ${\cal M}$ be a finite set of $m$ labels. An intersection graph is then constructed by assigning to each vertex $v \in V$ a subset $S_v$ of ${\cal M}$ and then connecting every pair of vertices that have common labels in their corresponding label sets. This thesis concerns the study of combinatorial properties, as well as the design and analysis of algorithms on two kinds of random intersection graphs models that arise from different choices of the distribution that we use to construct the sets $S_v$. In the first of these models, called \emph{Random Intersection Graphs Model} ${\cal G}_{n, m, p}$, each set of labels $S_v$ is constructed by choosing independently each label with probability $p$. In the second model, called \emph{Uniform Random Intersection Graphs Model} ${\cal G}_{n, m, \lambda}$, each label set $S_v$ is selected equiprobably (and independently for each vertex $v$) among all subsets of ${\cal M}$ of size $\lambda$. These models can be used to abstract situations that concern the efficient and secure communication in sensor networks, but can also be used to model the conflicts that occur in oblivious resource sharing in distributed settings. Moreover, random intersection graph models can be used to model social graphs, in which two entities are connected when they have a common feature. In the Random Intersection Graphs Model ${\cal G}_{n, m, p}$, we first study the existence and efficient construction of Hamilton cycles. More specifically, we give an upper bound for the probability $p$ that is needed for almost every random instance $G_{n, m, p}$ of the model to have a Hamilton cycle. We also present two polynomial time, randomized algorithms for constructing Hamilton cycles in a wide range of the parameters $m, p$. Moreover, we show that almost every random instance of the ${\cal G}_{n, m, p}$ model is an expander, even for $p$ very close to the connectivity threshold. Finally, we give close to optimal bounds (that hold with probability that goes to 1 for a wide range of the parameters of the model) for important quantities (like the mixing time and the cover time) concerning random walks on random instances of ${\cal G}_{n, m, p}$. In the Uniform Random Intersection Graphs Model ${\cal G}_{n, m, \lambda}$ we study the existence of Hamilton cycles for a ce rtain range of the parameters $m, \lambda$. Finally, by using the probabilistic method we compute the independence number of ${\cal G}_{n, m, \lambda}$.