Medium Access Control for Wireless Sensor Networks based on Impulse Radio Ultra Wideband

This paper describes a detailed performance evaluation of distributed Medium Access Control (MAC) protocols for Wireless Sensor Networks based on Impulse Radio Ultra Wideband (IR-UWB) Physical layer (PHY). Two main classes of Medium Access Control protocol have been considered: Slotted and UnSlotted with reliability. The reliability is based on Automatic Repeat ReQuest (ARQ). The performance evaluation is performed using a complete Wireless Sensor Networks (WSN) simulator built on the Global Mobile Information System Simulator (GloMoSim). The optimal operating parameters are first discussed for IR-UWB in terms of slot size, retransmission delay and the number of retransmission, then a comparison between IR-UWB and other transmission techniques in terms of reliability latency and power efficiency

Simulation Platform for Wireless Sensor Networks Based on Impulse Radio Ultra Wide Band

Impulse Radio Ultra Wide Band (IR-UWB) is a promising technology to address Wireless Sensor Network (WSN) constraints. However, existing network simulation tools do not provide a complete WSN simulation architecture, with the IR-UWB specificities at the PHYsical (PHY) and the Medium Access Control (MAC) layers. In this paper, we propose a WSN simulation architecture based on the IR-UWB technique. At the PHY layer, we take into account the pulse collision by dealing with the pulse propagation delay. We also modelled MAC protocols specific to IRUWB, for WSN applications. To completely fit the WSN simulation requirements, we propose a generic and reusable sensor and sensing channel model. Most of the WSN application performances can be evaluated thanks to the proposed simulation architecture. The proposed models are implemented on a scalable and well known network simulator: Global Mobile Information System Simulator (GloMoSim). However, they can be reused for all other packet based simulation platforms

Forecasting the Europe 2020 headline target on education and training. A panel data approach

This analysis aims at proposing simple econometric models that can be used to forecast early leavers from education and training and tertiary education attainment benchmarks up to year 2020. The models are built on the theoretical framework of human capital and optimal schooling decisions and then estimated in a panel setting to better deal with a limited dataset. By looking back at the time period of enrolment and graduation, our approach could be seen as an attempt to identify the determinants that shape the education decisions of young individuals. We construct the forecasts under very simple assumptions about the expected adults’ education attainment and given the determinants of schooling decisions uncovered by our empirical analysis. The forecasts tell us how early school leaving and tertiary education attainment are likely to develop over the next years if nothing changes in terms of policy measures. This very strong assumption provides scope for policy action especially for those countries where the expected developments of model’s determinants are not enough to foresee a positive outcome.JRC.G.3-Econometrics and applied statistic