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Um partido em mutação: a transformação do PT e seus reflexos sobre as campanhas presidenciais (1989-2002).
(Universidade Federal de São Carlos, 2004-03-02) Ribeiro, Pedro José Floriano; Azevedo, Fernando Antonio Farias de
Under a sartorian perspective, we characterized the Brazilian Workers Party (PT) as an anti-system party until the middle of the 90´s, because in some of their actions the party s objective was to cause symbolic impacts that could unlegitimize the Brazilian political system. Using the Panebianco s theoretical model, we try to explain how PT processed the institutional changes that made the party leaves gradually its anti-systemic character, making it possible its approach in relation to the centrist political forces that became clear in the presidential electoral campaign in 2002. Such migration toward the center nominated by political variable, and the quest for more competitiveness in a competitiveness variable were essential for the 2002 electoral campaign s modernization when Lula conquered the Presidency. This modernization was verified by an comparative cases study which compared this with the 1989 electoral campaign, very close to the non-modernized polo, according to un archetype constructed by Mancini and Swanson; the electoral campaigns analyzed represented reflections of the party s mutation.
Avaliação de aspectos fluidodinâmicos e da transferência de calor em leito fixo com escoamento gás-líquido concorrente vertical
(Universidade Federal de São Carlos, 2004-03-02) Moreira, Marcos Flávio Pinto; Freire, José Teixeira; https://lattes.cnpq.br/2270677706718167
In this work, the heat transfer in packed bed with gas-liquid co-current downflow and upflow was investigated. The influence of hydrodynamic factors, of the size and shape of particles, of the length of the thermal section and of the direction of flow on thermal parameters were evaluated. At first, a study about the hydrodynamic behavior (flow regimes and liquid saturation) were carried out. It was verified that flow regimes and liquid saturation were affected by gas and liquid flow rates and particle characteristics (shape and size). Five pseudo-homogeneous models were evaluated in order to obtain the thermal parameters. The traditional model to two-parameters was chosen because it presented good fits and more reliable parameters. The heat transfer was higher in upflow than in downflow. The temperature profiles obtained were flat in some conditions in upflow. The wall-heat transfer coefficient (hW) was affected by the length of the thermal section and mainly, by liquid flow rate in both downflow and upflow. The radial effective thermal conductivity (kr) also was affected by the length of the thermal section and liquid flow rate. The gas flow rate affected this parameter in upflow. Besides, the particle characteristics, shape and mainly size, affected kr.
Processos Paramétricos em eletrodinâmica quântica de cavidades
(Universidade Federal de São Carlos, 2004-03-02) Villas-Bôas, Celso Jorge; Moussa, Miled Hassan Youssef; https://lattes.cnpq.br/7828776012924524; https://lattes.cnpq.br/5700887540085418
In this thesis we study the interaction between an atom and a cavity mode submitted to linear and parametric amplifications. The evolution operator of the system was derived through the technique of time-dependent invariants of Lewis and Riesenfeld. We show how to prepare several squeezed states of the cavity field and, particularly, the truly mesoscopic "Schrödinger cat"-like state. When submitting such a mesoscopic superposition to the action of a likewise squeezed reservoir, we demonstrate that under specific conditions the decoherence time of the state is about the relaxation time of the cavity field. Next, the amplification process was engineered through the interaction of a single driven three-level atom with two cavity modes. Depending on the configuration of the atomic levels we obtain the parametric up- or down-conversion process between the cavity modes. With these processes we show how to generate one-mode mesoscopic squeezed superpositions (such as squeezed "Schrödinger cat"-like states), two-mode squeezed vacuum states (such as the original Eisntein-Podolsky-Rosen state (EPR)), and two-mode entanglements (such as the even and odd EPR states). The degree of squeezing achieved is up to 95% with currently feasible experimental parameters in cavity quantum electrodynamics. For the atom-field interaction time required in our technique, related to the high coupling parameter, the dissipative mechanism becomes practically negligible.