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Um framework para gerenciamento de qualidade de serviço em dispositivos móveis
(Universidade Federal de São Carlos, 2004-05-10) Hobeika, Camillo Tannuri; Zorzo, Sérgio Donizetti; https://lattes.cnpq.br/2523715806470871
This work presents a Framework for Multimedia Applications with objective to make possible the use of these applications in Mobile Devices with limited computational capacity, considering the aspects of Quality of Service that can currently be used in these devices. The technological evolution cause a accented growth in the number of mobile device`s users, a time that the quality of the services also tends to increase, mainly as for the multimedia applications. Had to the characteristics of these devices and the nets where they operate, the traffic of multimedia information tends to increase the communication typical problems. However, parameters of Quality of Service (QoS) can be established and actions can be taken to try to diminish the impact of the inherent problems to the mobile computation in the multimedia applications. Thus, this work aims at the research and the development of one framework based on components for applications developed on the platform Java 2 Micro Edition (J2METM), of form to offer to greater quality in the multimedia communication for the mobile devices that possess limited resources.
Caracterização físico-química de PET ramificado e de suas blendas com PET reciclado
(Universidade Federal de São Carlos, 2004-05-10) Prette, Lucas Del; Zanin, Maria; https://lattes.cnpq.br/9685965969782429; https://lattes.cnpq.br/9897264455881060
The growing concern with the solid residues management, observed in the last decade, due to its huge amount and impact, has motivated the search for recycling processes, where these residues can be reprocessed to generate new products, enlarging the cycle of materials and energy which are present in them. Special attention is given to the recycling of PET from containers of carbonated drinks. During the recycling of PET, the action of degradative fenomena creates a recycled resin with inferior properties, when compared to the original one, which difficults the use in new cycles of processing. The use of processing additives can overcome this effect. The improvement on the processability and modifications in the final properties of products made with blends of branched and linear resins have been reported in the literature. The branched resin could act as a processing additive. Even though some studies have characterized branched PET resins, the mixture of branched PET with recycled PET has not been reported before. Therefore, this study has as objective the characterization of a branched PET resin for use as processing additive in recycled PET and the characterization of the properties of the blends made with these two resins. In a first step, the characterization of the branched and recycled PET has been performed, and their properties compared with a bottle grade PET resin. The resins have been reprocessed to study the effect of the reprocessing over their properties. Modifications on the viscoelastic properties have been observed; the melt viscosity diminished, due to the degradation suffered during the process; the branched resin showed higher viscosity and melt strength. Next, the branched and recycled PET were blended. Improvements on the rheological properties were observed. The blends showed potential for use in transformation processes where higher melt strength is required.