The contents of this work investigate the capability of integrating the PT in applications by invoking the ratio of the throughput power to volume represented by the term: power density. The fundamentals of the PT are introduced in chapter two. In chapter three, the fundamental limitations of the PT's capability of transferring power to the load are studied. There are three major limitations: temperature rise due to losses during operation, electromechanical limits of material, and interactions with output rectifier. The analysis and estimation are then verified by experiments and calculations implemented on three different PT samples fabricated from three different manufacturers. The subject of chapter four is the behavior of the PT's power amplifier. This chapter concentrates on two main amplifier topologies, optimized based on the simplicity of structure and minimization of components (passive and active): class D and class E amplifiers. The operational characteristics of these amplifiers with the PT are then comparison. Methods to track the optimum frequency and discontinuous working mode of the PT are proposed as the approaches to improve the energy transfer of the PT. In chapter five, prototypes of four devices using a PT are developed and introduced as illustrations of the integration of PTs into practical applications: an igniter for high intensity discharge (HID) lamps, high DC voltage power supplies, and electronic ballasts for LEDs, and stand-alone ionizers for food sterilizers. Some concluding statements and ideas for future works are located in the last chapter - chapter six.

Cette thèse est consacrée à l'étude des équations du Darcy Brinkman Forchheimer (DBF) avec des conditions aux limites non standards. Nous montrons d'abord l'existence de différents type de solutions (faible, forte) correspondant au problème DBF stationnaire dans un domaine simplement connexe avec des conditions portants sur la composante normale du champ de vitesse et la composante tangentielle du tourbillon. Ensuite, nous considérons le système Brinkman Forchheimer (BF) avec des conditions sur la pression dans un domaine non simplement connexe. Nous prouvons que ce problème est bien posé ainsi que l'existence de la solution forte. Nous établissons la régularité de la solution dans les espaces L^p pour p >= 2.L'étude et l'approximation du problème DBF non stationnaire est basée sur une approche pseudo-compressibilité. Une estimation d'erreur d'ordre deux est établie dans le cas o\`u les conditions aux limites sont de types Dirichlet ou Navier.Enfin, une méthode d'éléments finis Galerkin Discontinue est proposée et la convergence établie concernant le problème DBF linéarisé et le système DBF non linéaire avec des conditions aux limites non standard. / This thesis is devoted to Darcy Brinkman Forchheimer (DBF) equations with a non standard boundary conditions. We prove first the existence of different type of solutions (weak, strong) of the stationary DBF problem in a simply connected domain with boundary conditions on the normal component of the velocity field and the tangential component of the vorticity. Next, we consider Brinkman Forchheimer (BF) system with boundary conditions on the pressure in a non simply connected domain. We prove the well-posedness and the existence of a strong solution of this problem. We establish the regularity of the solution in the L^p spaces, for p >= 2.The approximation of the non stationary DBF problem is based on the pseudo-compressibility approach. The second order's error estimate is established in the case where the boundary conditions are of type Dirichlet or Navier. Finally, the finite elements Galerkin Discontinuous method is proposed and the convergence is settled concerning the linearized DBF problem and the non linear DBF system with a non standard boundary conditions.

L’analyse syntaxique consiste à prédire la représentation syntaxique de phrases en langue naturelle sous la forme d’arbres syntaxiques. Cette tâche pose des problèmes particuliers pour les langues non-configurationnelles ou qui ont une morphologie flexionnelle plus riche que celle de l’anglais. En particulier, ces langues manifestent une dispersion lexicale problématique, des variations d’ordre des mots plus fréquentes et nécessitent de prendre en compte la structure interne des mots-formes pour permettre une analyse syntaxique de qualité satisfaisante. Dans cette thèse, nous nous plaçons dans le cadre de l’analyse syntaxique robuste en constituants par transitions. Dans un premier temps, nous étudions comment intégrer l’analyse morphologique à l’analyse syntaxique, à l’aide d’une architecture de réseaux de neurones basée sur l’apprentissage multitâches. Dans un second temps, nous proposons un système de transitions qui permet de prédire des structures générées par des grammaires légèrement sensibles au contexte telles que les LCFRS. Enfin, nous étudions la question de la lexicalisation de l’analyse syntaxique. Les analyseurs syntaxiques en constituants lexicalisés font l’hypothèse que les constituants s’organisent autour d’une tête lexicale et que la modélisation des relations bilexicales est cruciale pour désambiguïser. Nous proposons un système de transition non lexicalisé pour l’analyse en constituants discontinus et un modèle de scorage basé sur les frontières de constituants et montrons que ce système, plus simple que des systèmes lexicalisés, obtient de meilleurs résultats que ces derniers. / Syntactic parsing consists in assigning syntactic trees to sentences in natural language. Syntactic parsing of non-configurational languages, or languages with a rich inflectional morphology, raises specific problems. These languages suffer more from lexical data sparsity and exhibit word order variation phenomena more frequently. For these languages, exploiting information about the internal structure of word forms is crucial for accurate parsing. This dissertation investigates transition-based methods for robust discontinuous constituency parsing. First of all, we propose a multitask learning neural architecture that performs joint parsing and morphological analysis. Then, we introduce a new transition system that is able to predict discontinuous constituency trees, i.e.\ syntactic structures that can be seen as derivations of mildly context-sensitive grammars, such as LCFRS. Finally, we investigate the question of lexicalization in syntactic parsing. Some syntactic parsers are based on the hypothesis that constituent are organized around a lexical head and that modelling bilexical dependencies is essential to solve ambiguities. We introduce an unlexicalized transition system for discontinuous constituency parsing and a scoring model based on constituent boundaries. The resulting parser is simpler than lexicalized parser and achieves better results in both discontinuous and projective constituency parsing.

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The thesis is dedicated to the study and numerical analysis of the non- linear flows in the porous media, using general Forchheimer models. In the numerical analysis, the local discontinuous Galerkin method is chosen. The first part of the paper is dedicated to the derivation of the studied equations based on the physical motivation and summarizing the theory needed for the further analysis. Core of the thesis consists of the introduction of the chosen discretization method and the derivation of the main stability and a priory error estimates, optimal for the linear ansatz functions. At the end we present a couple of numerical experiments to verify the results. 1

This work presents implementation of a hybridized discontinuous Galerkin (DG) method for robust simulation of the hypersonic aerothermoelastic multiphysics system. Simulation of hypersonic vehicles requires accurate resolution of complex multiphysics interactions including the effects of high-speed turbulent flow, extreme heating, and vehicle deformation due to considerable pressure loads and thermal stresses. However, the state-of-the-art procedures for hypersonic aerothermoelasticity are comprised of low-fidelity approaches and partitioned coupling schemes. These approaches preclude robust design and analysis of hypersonic vehicles for a number of reasons. First, low-fidelity approaches limit their application to simple geometries and lack the ability to capture small scale flow features (e.g. turbulence, shocks, and boundary layers) which greatly degrades modeling robustness and solution accuracy. Second, partitioned coupling approaches can introduce considerable temporal and spatial inaccuracies which are not trivially remedied. In light of these barriers, we propose development of a monolithically-coupled hybridized DG approach to enable robust design and analysis of hypersonic vehicles with arbitrary geometries. Monolithic coupling methods implement a coupled multiphysics system as a single, or monolithic, equation system to be resolved by a single simulation approach. Further, monolithic approaches are free from the physical inaccuracies and instabilities imposed by partitioned approaches and enable time-accurate evolution of the coupled physics system. In this work, a DG method is considered due to its ability to accurately resolve second-order partial differential equations (PDEs) of all classes. We note that the hypersonic aerothermoelastic system is composed of PDEs of all three classes. Hybridized DG methods are specifically considered due to their exceptional computational efficiency compared to traditional DG methods. It is expected that our monolithic hybridized DG implementation of the hypersonic aerothermoelastic system will 1) provide the physical accuracy necessary to capture complex physical features, 2) be free from any spatial and temporal inaccuracies or instabilities inherent to partitioned coupling procedures, 3) represent a transition to high-fidelity simulation methods for hypersonic aerothermoelasticity, and 4) enable efficient analysis of hypersonic aerothermoelastic effects on arbitrary geometries.

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This report is about examining the fields of machine learning and digital marketing, using machine learning as a tool to predict churn in a new domain of companies that do not track their customers extensively, i.e where behaviour data is discontinuous.  To predict churn relatively simple out of the box models, such as support vector machines and random forests, are used to achieve an acceptable outcome. To be on par with the models used for churn prediction in subscription based services, this report concludes that more research has to be done using more effective evaluation metrics. Finally it is presented how these discoveries can be commercialized and the business related benefits of using churn prediction for the employer Sellpy. / Denna rapport handlar om att utforska fälten maskininlärning och digital marknadsföring, genom att använda maskininlärning som ett redskap för att förutspå churn i en typ av företag med diskontinuerlig beteendedata. För att förutspå churn finns relativt simpla "out of the box"-modeller, som support vector machines och random forests, som används för att nå acceptabla resultat. För att nå liknande resultat som i arbeten där churn utförs på kontinuerlig beteendedata konstaterar denna rapport att framtida arbeten forska på vilka utvärderingsmetriker som är mest lämpade. I rapporten presenteras också hur dessa upptäckter kan kommersialiseras och hur företaget Sellpy kan tjäna på att förutspå churn.

In this thesis, we explore a novel approach to solving the Helmholtz equation,the WaveHolz iteration method. This method aims to overcome some ofthe difficulties with solving the Helmholtz equation by providing a highlyparallelizable iterative method based on solving the time-dependent Waveequation. If this method proves reliable and computationally feasible it wouldhave great value for future application. Therefore, it is of interest to evaluatethe performance and properties of this method. To fully evaluate this method,the method was implemented and conclusions were based on results fromsimulations of the method. The method was able to solve problems in threedimensions and it seems that the method is very well suited for parallelized computations. To replicate real-world scenarios simulations of problems ininfinite and curvilinear domains were conducted. Based on the result presentedhere it is possible to further refine the method, especially regarding the setupof the domain and the implementation of boundary conditions for infinitedomains. / I detta examensarbete presenteras en ny metod för att lösa Helmholtz ekvation, WaveHoltz iterativa metod. Målet med denna metod är att undkomma vissa problem som uppstår med andra metoder för att lösa Helmholtz ekvation genom att tillhandahålla iterativ metod som baseras på lösningar av den tidsberoende vågekvationen samt kan parallelliseras effektivt. Om denna metod visar sig vara stabil och effektiv beräkningsmässigt skulle detta medföra stor potential för framtida tillämpningar. Av denna anledning undersöks metoden och dess egenskaper. För att fullt ut kunna evaluera denna method implementerades den vartefter simuleringar genomfördes och slutsatser drogs. Med metoden var att det var möjligt att lösa problem i tre dimensioner och metoden visade sig vara lämplig för parallella beräkningar. För att återskapa verklighetstrogna scenarion beräknades problem i oändliga och kroklinjiga domäner. Baserat på resultaten som presenteras i denna rapport är det möjligt att förfina metoden, speciellt vid konstruktionen av komplicerade beräkningsnät och randvillkoren för de oändliga problemen.