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Uma arquitetura de Gateway com QoS para gerenciamento de tráfego de rede considerando restrições temporais das aplicações
(Universidade Federal de São Carlos, 2009-08-27) Marcello, Juliano; Trevelin, Luis Carlos; https://lattes.cnpq.br/5082419783043736; https://lattes.cnpq.br/8571611787891164
Applications with time restrictions are becoming common in our daily lives. These applications range from games to applications for controlling air traffic. Applications with time restrictions that use the Internet / Intranet as a mean of communication (e.g. streaming audio and video, VoIP and messaging PRC-RT), require that their packets be delivered before the end of its deadline. In these cases prioritize traffic from the packets generated by these applications in relation to the other packets is a way of trying to minimize the loss of deadlines. Thus this work presents an architecture of gateway with QoS and traffic forecasting that aims to focus on requests from time-restricted applications. Gateway classifies traffic based on the IEEE 802.1q standard, in six classes with different priorities and uses the Box-Jenkins mathematical model to predict the amount of traffic for each class of service and provide resources to meet the classes according to their priority.
Eletrodeposição de nanoestruturas de cobalto em alumina anódica porosa e sua caracterização magnética
(Universidade Federal de São Carlos, 2009-08-27) Oliveira, Cristiane Pontes de; Souza, Ernesto Chaves Pereira de; https://lattes.cnpq.br/1505400360366643; https://lattes.cnpq.br/3680344230876235
In this thesis, the results regarding the investigation about the cobalt electrodeposition in templates of porous anodic alumina are presented. The doctorade is divided in four main sections. The _rst one has consisted in exploring many experimental set up to the preparation of porous anodic alumina using galvanostatic mode. The main results are related to the high ordering achieved using the galvanostatic mode and the sistem versatility concerning preparation of new architectures in porous anodic alumina such as the two overlapped porous layers presented in this thesis. The second part is about the computational study of the metalic electrodeposition in porous templates. In this step a bidimensional model to the metal electrodeposition in porous sistem was developed and simulated. The model considers one potenciostatic pulse. Potential distribution inside the template is calculated using the Laplace equation. Difusion equation takes into account the transport of electroactive species. Simulations show clearly the interaction between the concentration gradient inside the pore and potential distribution in the oxide inner. This dynamic allows to understand the top deposition and is consistent with the catch up e_ect. Based on insights from early step, the cobalt electrodeposits in porous anodic alumina were prepared by galvanostatic and potentiostatic pulsed electrodeposition. Finaly, the fourth part of the work deal with the magnetic characterization of the cobalt electrodeposits. The electrodeposits prepared by galvanostatic pulsed electrodeposition presented the exchange bias behaviour. The exchange bias is result of the presence of antiferromagnetic cobalt oxide, which lead to the formation of ferromagnetic (Co)/antiferromagnetic (CoO) interfaces responsible by the increase in the coercive _eld when the sample is cooled at presence of high magnetic _eld (Field Cooling procedure - FC). In addition, it was observed a anomalous temperature dependence of coercive _eld. Regarding the electrodeposits prepared by potentiostatic pulsed electrodeposition, they showed similar temperature dependence of coercive _eld. The coercive _eld (HC1) increase as the temperature is reduced from 300 K, achieving a maximum around 100 K, and from this point, the coercive _eld decrease signi_cantly. According to the reversible magnetic susceptibility behaviour, this result is related to the magnetoelastic contribution to the sistem anisotropy.
Caracterização da incidência e evolução de pragas e doenças em agroecossistemas cafeeiros sob diferentes manejos
(Universidade Federal de São Carlos, 2009-08-27) Lopes, Paulo Rogério; Ferraz, José Maria Gusman; https://lattes.cnpq.br/3851804858390996; https://lattes.cnpq.br/0354540389206559
This research aims to characterize the incidence and development of major pests and diseases of coffee in agroecosystems under conventional, organicmineral, organic and agroforestry managements in two municipalities in the southern Minas Gerais State: Machado and Poço Fundo. It was carried out monthly monitoring of the leaf-miner (Leucoptera coffeella), borer coffee (Hypothenemus hampei), rust (Hemileia vastatrix) and brown eye spot (Cercospora coffeicola) for a period of one year (december/2007 the november/2008) in crops of Novo Mundo variety with spacing (3.0 to 3.5 m X 1.0 to 1.2 m). The monitoring of leaf-miner and diseases of the coffee was done through the collection of ten sheets of the third or fourth pair in all sides of the coffee, and twenty plants sampled by agroecosystem, totaling two hundred leaves collected for evaluation of pests and diseases in each system. To monitorate the borer coffee it was selected 32 plants, six different points on each plant (10 fruits grouped by set point) and there was non-destructive evaluation. In all agroecosystems monitored, both managed by the family farm, the infestation of the borer coffee and leaf-miner did not reach level of economic damage in any evaluation. With respect to diseases evaluated, it was observed that the rust and brown eye spot reached the level of economic damage in all management systems. However, the organic-mineral systems, organic (monoculture) and agroforestry (organic) the occurrence of rust was critical to reach high levels in the months april to october of 2008, and the values above 60% of incidence in four months of evaluation. The incidence of brown eye spot was relatively lower in the conventional and organic (monoculture), whose peaks did not exceed 41% and 55%, consecutively. Already in the organicmineral and agroforestry (organic) the occurrence of Cercospora reached very high levels, reaching 76% and 67% respectively in July. Despite the high incidence of rust and brown eye spot found in coffee agroecosystems organicmineral and organic, the average productivity achieved by these systems in the past three years was higher than the conventional, even the latter system investing heavy in pesticides and chemical fertilizers.