2 resultados para TIC

em Universidade Federal do Rio Grande do Norte(UFRN)


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The broad objective of the research The pedagogic use of ICT as development of teaching capacity: the case of ProInfo Natal/RN was to realize an evaluation of this program effectiveness in public schools. Specifically, we ve tried to observe if the program: a) succeeded by promoting the pedagogical use of new ICTs, b) stimulated the improvement of teaching and learning using ICT, and c) performed functionings and expanding its capabilities. The methodology consisted of literature revision; realization of half-structured interviews with administrators and teachers, and leading four focal groups with students in 9th grade of elementary school, were also made observations and analysis about the official documents which regulates the program. Our results showed that ProInfo presents various interferences in its effectiveness, causing a gap between its marks and the actual results of its use in everyday life of schools. We ve concluded that the program needs to challenge these weaknesses in order to contribute to the promotion of functionings and expanding its capabilities

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The obtaining of ceramic materials from polymeric precursors is subject of numerous studies due to lower energy costs compared to conventional processing. The aim of this study is to investigate and improve the mechanism for obtaining ceramic matrix composite (CMC) based on SiOC/Al2O3/TiC by pyrolysis of polysiloxane in the presence of an active filler and inert filler in the pyrolysis temperature lower than the usually adopted for this technique, with greater strength. It also investigates the influence of pyrolysis temperature, the content of Alas active filler, the presence of infiltrating agents (Al, glass and polymer) after pyrolysis, temperature and infiltration time on some physical and mechanical properties. Alumina is used as inert filler and Al and Ti as active filler in the pyrolysis. Aluminum, glass and polysiloxane are used as agents infiltrating the post-pyrolysis. The results are analyzed with respect to porosity and bulk density by the Archimedes method, the presence of crystalline phases by X-ray diffraction (XRD) and microstructure by scanning electron microscopy (SEM). The ceramic pyrolyzed between 850 °C 1400 °C contain porosity 15% to 33%, density 2.34 g/cm3 and flexural strength at 4 points from 30 to 42 MPa. The microstructure features are porous, with an array of Al2O3 reinforced by TiC particles and AlTi3. The infiltration post-pyrolysis reveals decrease in porosity and increase density and strength. The composites have potential applications where thermal stability is the main requirement