2 resultados para 1293

em Universidad Politécnica de Madrid


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The main objective of this paper is to review the state of the art of residential PV systems in France and Belgium. This is done analyzing the operational data of 10650 PV systems (9657 located in France and 993 in Belgium). Three main questions are posed. How much energy do they produce? What level of performance is associated to their production? Which are the key parameters that most influence their quality? During the year 2010, the PV systems in France have produced a mean annual energy of 1163 kWh/kWp in France and 852 kWh/kWp in Belgium. As a whole, the orientation of PV generators causes energy productions to be some 7% inferior to optimally oriented PV systems. The mean Performance Ratio is 76% in France and 78% in Belgium, and the mean Performance Index is 85% in both countries. On average, the real power of the PV modules falls 4.9% below its corresponding nominal power announced on the manufacturer?s datasheet. A brief analysis by PV modules technology has lead to relevant observations about two technologies in particular. On the one hand, the PV systems equipped with Heterojunction with Intrinsic. Thin layer (HIT) modules show performances higher than average. On the other hand, the systems equipped with Copper Indium (di)Selenide (CIS) modules show a real power that is 16 % lower than their nominal value.

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Abstract The aim was to examine the injuries sustained by Spanish football players in the First Division and to compare injury-related variables in the context of both competition and training. The injury data were prospectively collected from 16 teams (427 players) using a specific web-based survey during the 2008/2009 season. A total of 1293 injuries were identified (145 were recurring injuries). The overall injury incidence was 5.65 injuries per 1000 h of exposure. Injuries were much more common during competition than during training (43.53 vs. 3.55 injuries per 1000 h of exposure, P menor que 0.05). Most of the injuries (89.6%) involved the lower extremities, and overuse (65.7%) was the main cause. Muscle and tendon injuries were the most common types of injury (53.8%) among the players. The incidence of training injuries was greater during the pre-season and tended to decrease throughout the season, while the incidence of competition injuries increased throughout the season (all P menor que 0.05). In conclusion, the results of this study suggest the need for injury prevention protocols in the First Division of the Spanish Football League to reduce the number of overuse injuries in the muscles and tendons in the lower extremities. In addition, special attention should be paid during the pre-season and the competitive phase II (the last four months of the season) in order to prevent training and competition injuries, respectively.