Le travail de thèse exposé dans ce manuscrit porte sur le développement et l'analyse numérique de schémas volumes finis de type dualité discrète (DDFV) pour la discrétisation des équations de Darcy et des équations de Stokes. Un point commun à ces problèmes, qui motive l'emploi des schémas DDFV, est que leur résolution par volumes finis nécessite d'approcher toutes les composantes du gradient de la solution. On étudie tout d'abord la discrétisation du problème de diffusion scalaire anisotrope pour des conditions aux bords mixtes de type Dirichlet/Fourier. Le schéma que nous proposons permet de construire un algorithme de Schwarz discret associé à une décomposition de domaine sans recouvrement qui converge vers la solution obtenue sans décomposition. Des expériences numériques illustrent les résultats théoriques d'estimation d'erreur et de convergence des algorithmes de Schwarz DDFV. On se propose ensuite de discrétiser des problèmes de Stokes avec une viscosité variable. Les schémas DDFV correspondant sont en général mal posés. Pour y remédier, on stabilise le bilan de masse par différents termes en pression. Dans un second temps, on considère le cas où la viscosité est discontinue. Ces discontinuités doivent être prise en compte par le schéma pour surmonter la perte de consistance des contraintes à l'interface. Ensuite une première étude de l'extension des schémas DDFV aux équations de Navier-Stokes est présentée aussi qu'une généralisation des résultats pour le problème de Stokes avec une viscosité régulière dans le cas tridimensionnel.

Reference radiation fields for x-ray qualities are described by the International Organization of Standards (ISO). This study describes the procedure to establish nine different low energy X-ray qualities at the national metrology laboratory, Swedish Radiation Protection Authority, following the document ISO 4037. Measurements of tube voltage, half-value layer, mean energy and spectral resolution have been performed for qualities N-15, N-20, N-25, N-30, N-40, L-20, L-30, L-35 and L-55. Furthermore, dose equivalent conversion coefficients for operational quantities ambient dose equivalent, personal dose equivalent and directional dose equivalent have been calculated by folding the mono-energetic conversion factors with measured spectral distributions of the x-ray qualities. The spectral distributions were unfolded from pulse-height distributions to photon distributions using simulated data of the semi-conductor detector used for measurements, generated with the Monte Carlo code PENELOPE.

The Fibonomial numbers are defined by \[ \begin{bmatrix}n \\ k \end{bmatrix} = \frac{\prod_{i=n-k+1} ^{n} F_i}{\prod_{j=1}^{k} F_j} \] where $F_i$ is the $i$th Fibonacci number, defined by the recurrence $F_n=F_{n-1}+F_{n-2}$ with initial conditions $F_0=0,F_1=1$. In the past year, Sagan and Savage have derived a combinatorial interpretation for these Fibonomial numbers, an interpretation that relies upon tilings of a partition and its complement in a given grid.In this thesis, I investigate previously proven theorems for the Fibonomial numbers and attempt to reinterpret and reprove them in light of this new combinatorial description. I also present combinatorial proofs for some identities I did not find elsewhere in my research and begin the process of creating a general mapping between the two different Fibonomial interpretations. Finally, I provide a discussion of potential directions for future work in this area.

Les modèles physico-chimiques destinés à représenter la réalité expérimentale peuvent se révéler inadéquats. C'est le cas du piège à oxyde d'azote, utilisé comme support applicatif de notre thèse, qui est un système catalytique traitant les émissions polluantes du moteur Diesel. Les sorties sont des courbes de concentrations des polluants, qui sont des données fonctionnelles, dépendant de concentrations initiales scalaires.L'objectif initial de cette thèse est de proposer des plans d'expériences ayant un sens pour l'utilisateur. Cependant les plans d'expérience s'appuyant sur des modèles, l'essentiel du travail a conduit à proposer une représentation statistique tenant compte des connaissances des experts, et qui permette de construire ce plan.Trois axes de recherches ont été explorés. Nous avons d'abord considéré une modélisation non fonctionnelle avec le recours à la théorie du krigeage. Puis, nous avons pris en compte la dimension fonctionnelle des réponses, avec l'application et l'extension des modèles à coefficients variables. Enfin en repartant du modèle initial, nous avons fait dépendre les paramètres cinétiques des entrées (scalaires) à l'aide d'une représentation non paramétrique.Afin de comparer les méthodes, il a été nécessaire de mener une campagne expérimentale, et nous proposons une démarche de plan exploratoire, basée sur l'entropie maximale.

Achieving acceptable plane wave uniformity throughout an expanded volume is necessary to conduct scattering measurements on a large target in a controlled environment. An expanded volume is large relative to the size of the nearfield array configuration used to produce plane wave uniformity. The optimum set of shading coefficients for a nearfield array may not produce acceptable plane wave uniformity as the volume and frequency domain are expanded for a given array configuration. Choosing the frequency domain as a single frequency for an optimum set of coefficients will produce plane wave uniformity throughout the largest possible volume for a given array configuration. This study determines the acceptability of uniformity results produced by an optimum set of frequency dependent coefficients throughout an expanded volume for two array configurations that comprise a system for measuring bistatic target strength in the nearfield. Minimizing the frequency domain chosen for an optimum set of coefficients will produce plane wave uniformity for the largest possible volume for a given array configuration. This study determines the acceptability of uniformity results produced by an optimum set of frequency dependent coefficients throughout an optimistic volume for two array configurations that comprise a bi-static array.

Carbon dioxide (CO2) is the most important component of Greenhouse Gas (GHG) that causes global warming and sea-level rising. Thermal power plants dominate electric power generation in the world, and has been reported to be the major contributor of CO2 emission. To prevent the related global warming caused by GHG emission, carbon quota trading is implemented and becomes a gradually arising market. This thesis proposed a research focused on the relationship between the carbon trading scheme and dynamic economic dispatch (DED) problem for the public utility. A model of the carbon trading market was investigated and introduced into DED problem incorporating wind and solar power plant. A refined particle swarm optimization (PSO) algorithm, PSO with time-varying acceleration coefficients (PSO-TVAC), is applied to determine the DED strategy with the incorporation of independent power providers (IPPs) and green power plant. The model of the carbon trading was considered in the DED problem. Carbon reduction is treated as the inner-cost of utility, and the fictitious carbon quotas can be resold to the market, while the energy shortage can be satisfied by purchasing quotas from the market. In order to avoid premature convergence of the original PSO, the PSO-TVAC method is introduced to improve the searching efficiency.

A Mandarin phrase recognition system based on MFCC, LPC scaled excitation, vowel model, hidden Markov model (HMM) and Viterbi algorithm is proposed in this thesis. HMM, which is broadly used in speech recognition at present, is adopted in the main structure of recognition. In order to speed up the recognition time, we take advantage of stability of vowels in Mandarin and incorporate with vowel class recognition in our system. For the speaker-dependent case, a single Mandarin phrase recognition can be accomplished within 1 seconds on average in the laboratory environment.

In the TDB[1]-like corpora annotation efforts, which are constructed by the intuitions of the annotators, the reliability of the corpus can only be determined via correct interannotator agreement measurement methodology (Artstein, &amp / Poesio, 2008). In this thesis, a methodology was defined to measure the inter-annotator agreement among the TDB annotators. The statistical tests and the agreement coefficients that are widely used in scientific communities, including Cochran&rsquo / s Q test (1950), Fleiss&rsquo / Kappa (1971), and Krippendorff&rsquo / s Alpha (1995), were examined in detail. The inter-annotator agreement measurement approaches of the various corpus annotation efforts were scrutinized in terms of the reported statistical results. It was seen that none of the reported interannotator agreement approaches were statistically appropriate for the TDB. Therefore, a comprehensive inter-annotator agreement measurement methodology was designed from scratch. A computer program, the Rater Agreement Tool (RAT), was developed in order to perform statistical measurements on the TDB with different corpus parameters and data handling approaches. It was concluded that Krippendorff&rsquo / s Alpha is the most appropriate statistical method for the TDB. It was seen that the measurements are affected with data handling approach preferences, as well as the used agreement statistic methods. It was also seen that there is not only one correct approach but several approaches valid for different research considerations. For the TDB, the major data handling suggestions that emerged are: (1) considering the words as building blocks of the annotations and (2) using the interval approach when it is preferred to weigh the partial disagreements, and using the boundary approach when it is preferred to evaluate all disagreements in same way.

Long span bridges are susceptible to wind. Hence it is important to study their wind-induced vibrations to avoid any probable structural failures. In this thesis, the results of an experimental and computational investigation of the aerodynamic characteristics of trapezoid bridge deck cross-sections with three different aspect ratios (10, 12 and 15) and four different side angles (75&ordm / , 60 &ordm / , 45 &ordm / and 30 &ordm / ) are analyzed and presented. The flow around rigid fixed bridge deck models is investigated to obtain the relevant aerodynamic coefficients and the vortex shedding frequency and Strouhal number. Two dimensional unsteady Reynolds Averaged Navier-Stokes equations are solved using commercial CFD software at different Reynolds numbers. The numerical results are compared with the experimental data obtained by testing the model bridge decks geometries in a low speed wind tunnel. The results of this study demonstrate that the models aerodynamic parameters except their lift coefficient are almost dependent on the aspect ratio. In addition, the influence of side angle on all aerodynamic parameters has to be taken in account.

The mechanical properties of materials are usually evaluated by performing a tensile or hardness test on the sample. Tensile tests are often time consuming, destructive and need specially prepared specimens. On the other hand, there is no direct theoretical correlation between the hardness number and the mechanical properties of a material although phenomenological relationships do exist. The advantages of indentation techniques are that they are non-destructive, quick, and can be applied to small material samples and localized in fashion. Mechanical properties are typically determined from spherical indentation load-depth curves. This process is again a time consuming one and not suitable for situations where a quick assessment is required such as in the sheet metal rolling industry. In the present study, a novel method of measuring mechanical properties of the material by multiple spherical indentations is developed. A series of indentations are made on the substrate with a spherical indenter with different loads. The diameter of the indentation is related to the load applied to determine the mechanical properties of the material, namely the yield strength and the work hardening parameters. To determine the diameter of the indentation quickly, a fiber optic sensing technique is developed. An incident light beam from a semiconductor laser is coupled back into an optical fiber upon reflection from the metal surface. By measuring the diffused light power reflected from the metal surface, the diameter of the indentation is measured. The spherical indentation technique is difficult for real time mechanical property measurement of sheet metal in a processing line. Problems arise as the strip is traveling at 2,000 to 4,000 ft/min (10,000 to 20,000 mm/sec) in the processing line. As a first step in developing a process that could be implemented in a real time processing line, a preliminary study has been conducted for the prediction of yield strength by laser shock processing.