Determinação dos parâmetros do controlador preditivo generalizado com função de pesos variante no tempo através de algoritmos genéticos

The predictive control technique has gotten, on the last years, greater number of adepts in reason of the easiness of adjustment of its parameters, of the exceeding of its concepts for multi-input/multi-output (MIMO) systems, of nonlinear models of processes could be linearised around a operating point, so can clearly be used in the controller, and mainly, as being the only methodology that can take into consideration, during the project of the controller, the limitations of the control signals and output of the process. The time varying weighting generalized predictive control (TGPC), studied in this work, is one more an alternative to the several existing predictive controls, characterizing itself as an modification of the generalized predictive control (GPC), where it is used a reference model, calculated in accordance with parameters of project previously established by the designer, and the application of a new function criterion, that when minimized offers the best parameters to the controller. It is used technique of the genetic algorithms to minimize of the function criterion proposed and searches to demonstrate the robustness of the TGPC through the application of performance, stability and robustness criterions. To compare achieves results of the TGPC controller, the GCP and proportional, integral and derivative (PID) controllers are used, where whole the techniques applied to stable, unstable and of non-minimum phase plants. The simulated examples become fulfilled with the use of MATLAB tool. It is verified that, the alterations implemented in TGPC, allow the evidence of the efficiency of this algorithm

Avaliação clínica e comparativa da oclusão balanceada bilateral e desoclusão com guia canino sobre a função mastigatória de usuários de prótese total removível

The maintenance of masticatory function is especially important for patients who wear complete dentures due to the limitations of this type of prosthesis. Thus, the bilateral balanced occlusion (BBO) is used to achieve, besides other advantages, greater masticatory efficiency. However, analyzing critically the literature, it is observed that there is not enough scientific evidence that support the BBO as the most appropriate occlusal concept in complete dentures. This way, the purpose of the present study was to verify if complete dentures wearers with BBO present better masticatory efficiency and capacity than those with canine guidance (CG). A double-blind controlled crossover clinical trial was conducted. The sample was made of 24 completely edentulous patients. The subjects wore sets of complete dentures with both occlusal concepts for equal periods of 3 months. Objective data were collected through the masticatory efficiency test, performed by the colorimetric method, in which capsules of a synthetic material enclosing fuchsine- containing granules were used. Subjective data were recorded by patient´s ratings of their chewing function, which is the masticatory ability. No significant statistical difference was found for masticatory efficiency (p=0,0952) and masticatory ability (x2=0,5711/ p=0,4498) between the two occlusal concepts studied, as well as there was no correlation between these two variables (p=0,2985). Based on these results, it seems reasonable to use CG for the setup of complete dentures, since it is an easier and quicker technical procedure, until that future researches can come to complement this question

As condições e o sentido do trabalho doméstico realizado por adolescentes que residem no local de emprego

The house work is a reality for girls of humble class and one of the most found forms of work among adolescent workers. Moreover, it is a mean of work which reproduces poverty and gender relations within the society. The purpose of this essay in to understand the house work in the life of adolescent workers, emphasizing the meaning produced by these teenagers concerning the job they perform. In order to achieve such goal, questionnaires were applied to 332 adolescents, under 18 years old from public schools (from EJA-supletivo) in Natal, with the purpose of mapping the registration of this activity among young students. Next, 14 adolescents were interviewed in order to recognize the meaning of this work and its repercussions over the teenagery, such as school education, socialization, relations with employers and adolescent s self-image. Later we have noticed most workers among the students from public schools are housemaids. Furthermore, this work is used as a form of social ascension and it contributes for the search for better opportunities in the state capital for adolescents who leave the countryside trying to agree to education and remuneration. This work plays an important role, which is to reproduce gender relations, as a woman works to maintain the private space as a female space and maintains the man out of this relation. Besides it reproduces class relations, ethny and generation conflicts, in which the employer replaces the control the parents have in the adolescent s life. Summing up, this study about house work have negative aspects, related to exploitation, humiliation and mistreat, as well as positive ones, for it permits the adolescent to improve his life conditions. The most important thing is to look for a mean of work in which human and workers rights are respected