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Dinâmica da participação em órgãos colegiados : estudo de casos do IFSULDEMINAS-Campus Machado
(Universidade Federal de São Carlos, 2015-08-05) Moraes, Elivan Afonso; Kerbauy, Maria Teresa Miceli; https://lattes.cnpq.br/4762029784021248; https://lattes.cnpq.br/7963991850082904
This research whose the development was made through a case study it aims to analysis and subsequent evaluation of the effectiveness of collegiate bodies of IFSULDEMINAS-Campus Machado from the point of view of participation and participatory processes. Among the effectiveness existing concepts, it was adopted in this work which deals with the ability of institutions must produce results. This study model has been widely used in participatory institutions at the federal, state and municipal levels, in different public policy sectors, such as environment, health, social assistence, among others. He proposed the same discussion but adapted to collegiate bodies of an educational institution and it was possible to verify whether these channels actually meet the objectives for which they were created. These organisms are made in areas where debate various topics affecting the daily life of the academic community, so these are highly relevant participatory mechanisms. The followed study described by Vaz (2011), identifying the specific factors that influence and / or cause some extent the variation in results and consequently affect the ability of the organs to influence the actions and decision making. In this sense, three variables were used in the search: deliberative effectiveness, institutional design and exogenous factors. The results point to the existence of failures in all organs, to a greater or lesser extent. At the end some recommendations are shown to Campus Machado managers for correction purposes of the deficiencies.
Efeitos das condições de queima e densidade aparente sobre a sobrequeima em porcelanatos
(Universidade Federal de São Carlos, 2015-08-05) Contartesi, Flavia; Melchiades, Fábio Gomes; https://lattes.cnpq.br/4469106561041487; Boschi, Anselmo Ortega; https://lattes.cnpq.br/3259846931278607; https://lattes.cnpq.br/0374592570152743
The phenomenon of overfiring manifests in porcelain tiles and other products with high degree of vitrification, as a consequence of the expansion of gases trapped in closed pores, in the final stages of sintering. When it is not properly controlled, it generates swelling of the pieces and then they present dimensional problems, damages in the mechanical properties and low stain resistance in polished products. Porcelain tiles are products with strict requirements, water absorption ≤0.5% for glazed and ≤0.1% for technical ones, moreover the ceramics industries, nowadays, use firing cycles increasingly faster, which allows significant productivity increases and costs reductions. Associate both avoiding the phenomenon of overfiring is not an easy task. The aim of this study was to evaluate the effects of the green bulk density and the firing curve (heating rate and soaking time at the maximum temperature) on the characteristics of the final product and on the development of this phenomenon. To achieve the objectives, a factorial design of experiments (DOE) was used. The differences between the firing temperatures necessary to produce 0.5% of water absorption and to achieve the maximum bulk density were considered to determine the firing range before overfiring the porcelain tiles. The results indicate that the firing range is strongly influenced by the time the samples were kept at the maximum temperature of the firing cycle. At the same time, they also indicate the importance of the bulk density of the green bodies as a way to reduce the closed porosity of the fired bodies and consequently to prevent the production of overfired porcelain tiles.
Expansão por umidade de revestimentos cerâmicos : métodos de medida e variáveis envolvidas
(Universidade Federal de São Carlos, 2015-08-05) Nastri, Suelen; Melchiades, Fábio Gomes; https://lattes.cnpq.br/4469106561041487; Boschi, Anselmo Ortega; https://lattes.cnpq.br/3259846931278607; https://lattes.cnpq.br/8529558499239129
The expansion by humidity (EPU) is characterized by the increase in the size of the ceramic body when in contact with water in liquid or vapor. The phenomenon can contribute to the development of severe pathologies in ceramic coatings such as glaze and cracking of detachment after installation of facades. The EPU has been studied since the early twentieth century, and the studies led to the creation of today's existing commonalities. However, there are still many divergences about the measurement procedures both as regards the measurement of expansion, as the accelerated hydration method used to predict the expansion ceramic materials may suffer over time. In this sense, through this research project, intended to contribute to the improvement of moisture expansion of evaluation methods in ceramic tiles, as well as identifying the main variables responsible for the EPU in ceramic tiles currently produced in the country. To carry out the project, samples were collected from different commercial ceramics, preferably used for the coating of external facades. The EPUs these samples were characterized by different procedures in the laboratory, to planned changes in the methods of hydration of the samples as well as methods of quantifying the expansions undergone. Simultaneously, the selected products were characterized microstructurally to identify the factors that determine susceptibility to moisture expansion. Both hydration and the method for measuring the dimensional change affect EPU values obtained, the latter was more predominant. The study of the reburn temperatures showed that it is not necessary to use temperatures higher than 350 ° C. Hydration time of the study shows a continuous increase in moisture expansion values. Microstructural analysis helps in understanding the EPU phenomenon.