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Neste trabalho nós fazemos predições para o comportamento de grandezas observáveis a serem medidas nos futuros aceleradores de partículas e também no LHC. Nós estudamos três processos: elétron-núcleo (eA), fóton-fóton e próton-núcleo (pA). Nos processos eA nós calculamos as seções de choque de produção de mésons vetoriais e de fótons reais usando os modelos de saturação rcBK e b-CGC. Nós verificamos que apenas a produção de mésons pesados poderá nos dizer qual destes dois modelos é o mais correto para descrever a seção de choque dipolo-próton. No estudo dos processos fóton-fóton nós calculamos as seções de choque de espalhamento e a função de estrutura do fóton. Nós propomos um novo modelo de saturação para a interação entre dois dipolos de cor e comparamos suas predições com aquelas de um modelo disponível na literatura para esta interação. Nós verificamos que o nosso modelo prediz um crescimento bem menos acentuado para os observáveis calculados do que prediz o outro modelo. No último processo que estudamos, a colisão pA, nós calculamos as seções de choque de produção de charme e de bottom nas energias do LHC. Nós verificamos que os dados sobre a produção de charme serão os mais promissores na identificação de sinais de física de saturação. Nós também verificamos que o efeito de shadowing nuclear causa uma diminuição considerável na seção de choque de produção de charme, o que indica que este observável poderá ser útil na determinação da magnitude deste efeito. Por outro lado, apenas a seção de choque de produção de bottom apresenta o efeito de antishadowing. / In this thesis we make predictions for the behavior of observables that will be measured in future particle colliders and also at the LHC. We address three different types of collisions: electron-ion (eA), photon-photon and proton-nucleus (pA). For eA processes we calculate the vector meson and real photon production cross section using the saturation models rcBK and b-CGC. We observe that only the production of heavy mesons will be useful to determine which saturation model correctly describes the dipole-proton interaction. For the photon-photon process we calculate the total cross section as well as the photon structure function. We propose a new saturation model for the interaction between two color dipoles and we compare its predictions with those of other models available in the literature. We observe that our model predicts a much smoother growth of the observables than the other models. As for pA collisions, we calculate the cross section of charm and bottom production at LHC energies. We observe that charm production is very sensitive to saturation effects as well as to nuclear shadowing effects. Therefore, this observable can be useful to determine the dynamics of QCD at high energies, as well as the magnitude of the shadowing. On the other hand, only the bottom production cross section is sensitive to antishadowing effect.

The adaptive dynamic inversion control methodology uses dynamic inversion to calculate the control, and adaptation to compensate for the errors in the inversion due to model uncertainties. Traditionally, adaptive control assumes full authority control and lacks an adequate theoretical treatment for control in the presence of actuator saturation limits. The objective of this research is to investigate the problems introduced in the adaptive dynamic inversion control scheme due to bounds on the control, and design control strategies to overcome these problems. The unique contribution of this research is that it identifies the maximum possible domain of attraction considering the control position limit, and uses a switching control strategy to contain the plant within the maximum possible domain of attraction. Another novel idea is that of a direction consistent control constraint mechanism which maintains the resultant direction of the rate of change of state the same as that of the desired, even in the presence of control saturation. This research uses a modified adaptation mechanism to prevent incorrect adaptation arising from trajectory errors due to control saturation. Mathematical development of the control laws and the adaptation mechanisms is presented along with rigorous proofs for convergence of the tracking error and stability of the overall control scheme. Finally, numerical simulation results are presented to validate the control methodology.

No description available.

Neste trabalho nós fazemos predições para o comportamento de grandezas observáveis a serem medidas nos futuros aceleradores de partículas e também no LHC. Nós estudamos três processos: elétron-núcleo (eA), fóton-fóton e próton-núcleo (pA). Nos processos eA nós calculamos as seções de choque de produção de mésons vetoriais e de fótons reais usando os modelos de saturação rcBK e b-CGC. Nós verificamos que apenas a produção de mésons pesados poderá nos dizer qual destes dois modelos é o mais correto para descrever a seção de choque dipolo-próton. No estudo dos processos fóton-fóton nós calculamos as seções de choque de espalhamento e a função de estrutura do fóton. Nós propomos um novo modelo de saturação para a interação entre dois dipolos de cor e comparamos suas predições com aquelas de um modelo disponível na literatura para esta interação. Nós verificamos que o nosso modelo prediz um crescimento bem menos acentuado para os observáveis calculados do que prediz o outro modelo. No último processo que estudamos, a colisão pA, nós calculamos as seções de choque de produção de charme e de bottom nas energias do LHC. Nós verificamos que os dados sobre a produção de charme serão os mais promissores na identificação de sinais de física de saturação. Nós também verificamos que o efeito de shadowing nuclear causa uma diminuição considerável na seção de choque de produção de charme, o que indica que este observável poderá ser útil na determinação da magnitude deste efeito. Por outro lado, apenas a seção de choque de produção de bottom apresenta o efeito de antishadowing. / In this thesis we make predictions for the behavior of observables that will be measured in future particle colliders and also at the LHC. We address three different types of collisions: electron-ion (eA), photon-photon and proton-nucleus (pA). For eA processes we calculate the vector meson and real photon production cross section using the saturation models rcBK and b-CGC. We observe that only the production of heavy mesons will be useful to determine which saturation model correctly describes the dipole-proton interaction. For the photon-photon process we calculate the total cross section as well as the photon structure function. We propose a new saturation model for the interaction between two color dipoles and we compare its predictions with those of other models available in the literature. We observe that our model predicts a much smoother growth of the observables than the other models. As for pA collisions, we calculate the cross section of charm and bottom production at LHC energies. We observe that charm production is very sensitive to saturation effects as well as to nuclear shadowing effects. Therefore, this observable can be useful to determine the dynamics of QCD at high energies, as well as the magnitude of the shadowing. On the other hand, only the bottom production cross section is sensitive to antishadowing effect.

L’amélioration des techniques de caractérisation des granulats de béton recyclé (GBR) et une meilleure compréhension des propriétés des bétons fabriqués avec ces derniers permettraient de promouvoir l’utilisation des GBR. Ce travail vise à étudier l’influence de l’état de saturation des sables recyclés (SR) sur le comportement à l’état frais et durcissant des mortiers.La première partie de ce travail consiste à étudier l’absorption d’eau d’un SR par différentes méthodes. Les résultats montrent que l’absorption d’eau du SR est plus importante que celle du sable naturel (SN). Cependant, la valeur d’absorption d’eau du SR dépend étroitement de la méthode employée et du mode de pré-saturation. La deuxième partie est dédiée à l’influence de l’état de saturation sur la maniabilité des mortiers. Les résultats montrent que l’état de saturation initial, le mode de pré-saturation et le temps de pré-saturation influencent significativement la maniabilité des mortiers. L’influence de l’état de saturation du SR sur le comportement à l’état durci est ensuite étudiée à partir de deux mortiers contenant du SR à l’état sec et sursaturé. La microstructure est examinée au microscope électronique à balayage (MEB) associée à l’analyse d’images et également par essai d’indentation sous MEB. La résistance des mortiers contenant du SR est moins importante que celle des mortiers contenant du SN. L’état de saturation initial du SR influence peu la résistance en compression, la méso-porosité totale de la nouvelle zone d’interface (ITZ) et la dureté de la matrice cimentaire. En revanche, l’état de saturation du SR influence significativement la distribution de la méso-porosité dans la nouvelle ITZ. / Improved techniques of characterization of recycled concrete aggregate (RCA) and a better understanding of the properties of concrete based on RCA would promote their use. The aim of this work is to study the influence of the state of saturation of RCA, especially of recycled sand, on the fresh and hardened behavior of mortars. The first part of this work is dedicated to the study of water absorption of recycled sand (RS) by different methods. The results show that the water absorption of RS is greater than that of natural sand (NS). However, the water absorption value of the RS is closely related to the used method and the pre-saturation mode. The second part is dedicated to the influence of the saturation state of aggregates on the workability of mortars. The results show that the initial saturation state, the pre-saturation mode and the pre-saturation time significantly influence the workability of the mortars. The influence of the saturation state of recycled aggregates on the hardened behavior of mortar is then studied with two mortars based on recycled dry or over-saturated sand. The microstructure is explored by scanning electron microscopy (SEM) followed by image analysis and by indentation test under the SEM. The compressive strength of mortars containing RS is lower than that of mortars made with NS. Moreover, the initial saturation state of RS does not influence significantly the compressive strength of mortars, the mean porosity of the new interfacial transition zone (ITZ) and the micro-hardness of the cement matrix. However, the saturation state influences significantly the distribution of meso-porosity in the new ITZ.

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The goal of this paper is to explore the exponential increase of the released games on Steam’s digital distribution platform and its possible impact on Steam’s users. The paper focuses on the perception of the users of such phenomena as market saturation and possible change in the perceived quality of the games presented on the store front.