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Yes / The current Internet architecture appears to not be particularly suited to addressing the emerging needs of new classes of users who wish to gain access to multimedia services made available by ISPs, regardless of their location, while in motion and with a guaranteed level of quality. One of the main objectives of so-called nextgeneration systems is to overcome the limitations of today¿s available Internet by adopting an approach based on the integration of different mobile and fixed networks. The SUITED project moves in this direction since it aims at contributing to the design and deployment of the global mobile broadband system (GMBS), a unique satellite/terrestrial infrastructure ensuring nomadic users access to Internet services with a negotiated QoS. A description of the main features of the GMBS architecture, characterized by the integration of a multisegment access network with a federated ISP network is given in this article. The GMBS multimode terminal is schematically described, and an overview of the so-called QoS-aware mobility management scheme, devised for such a heterogeneous scenario,is provided.

No / This work presents a novel broadband monopole antenna for digital video broadcastingterrestrial (DVB-T) application. The proposed antenna consists of a grating patch and a concave rectangular ground plane with defected ground plane, and the Multiple Split-Ring Resonator (MSRR). The added part in the ground plane and the meta-material are used to enable the antenna height reduction for fixed ranges of operating frequency. The antenna can operate from 468 MHz to 894 MHz frequency range corresponding to 62.5% of impedance bandwidth for |S11|<-7.5 dB. Details of the proposed antenna designs and experimental results of the constructed prototypes are presented and discussed.

The Earth Radiation Budget Experiment (ERBE) is an operational system of radiometric instruments placed in Earth orbit by the National Aeronautics and Space Administration (NASA). Its purpose is to monitor those components of the Earth radiation budget which influence the weather and climate. The active cavity radiometer (ACR) instruments on board the ERBE satellites are periodically calibrated against internal standards and against the relatively well-known solar constant. In order to better understand the dynamic behavior of the instruments, a high resolution dynamic model has been developed and used to simulate the solar calibration. The instrument dynamic model consists of two elements: a radiation distribution factor model and a finite element model of the heat conduction process. The distribution factors, which lie at the heart of the simulation, distribute the thermal radiation incident to the instrument aperture over the diffuse-specular active cavity surface. The results of the model for a transient analysis during solar calibration are compared with two sets of operational data provided by NASA. Very acceptable agreement is found between the model results and the operational data. / Master of Science

The Amazon River drainage basin is known as the most biodiverse region in the world. Regarding freshwater fish, this region contains around 15% of the world's fish richness. The fish family Serrasalmidae have a variety of feeding preferences including Pacus (herbivores) and Piranhas (carnivores). Fruit eating fish species are evolutionarily the oldest species in the family and have a mutualistic interaction with flooded forests. Considering the diversity of feeding habits of the Serrasalmidae family, it represents an excellent model to study ecological questions related to factors that influence the spatial distribution of species and factors that contribute to the maintenance of biodiversity. I first analyzed how differences in dietary preferences influence the spatial distribution and habitat associations of species at the landscape scale using diet data and three proxies of habitat association derived from satellite products. Using Phylogenetic Generalized Least Squares models I evaluated the relationship between habitat association and feeding guilds. Differences in resource distribution (assessed through feeding guilds) can influence habitat associations. Considering the hydrological variability (i.e., floodplain extent) and landscape heterogeneity that characterize floodplains, the patterns of habitat association vary with the spatial scale considered. Second, I identified factors that aid in sustaining aquatic biodiversity in floodplain forests of the Amazon River basin, focusing on frugivorous fish. I used descriptors of the floodplain ecosystem- and landscape-level variables to assess their contribution to the maintenance of fish species richness. Using Generalized Linear Models (GLM) with negative binomial distribution I found that greater plant richness could offer a greater variety of food resources for frugivorous fishes and that a more extensive floodplain area provides larger forested habitat for fishes that depend on forest-derived food resources, as such subbasins with these characteristics support a greater frugivorous fish species richness. This work provides valuable information on species habitat associations by fish as well as food resource dynamics, floodplain dependence, and advances our understanding of the intricate relationship between forests and fish at a basin scale. This information is critical for assessing the impact of anthropogenic activities on freshwater ecosystems and can be used to inform conservation strategies in the tropics.