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A long-life high-power-factor integrated converter able to supply light-emitting diode (LED) lamps in high-pressuresodium lamp retrofitting applications is presented. The proposed converter is the integration of a buck-boost converter with a buck converter, thus providing the necessary high input power factor and voltage transformation ratio to supply the low-voltage LED array from the mains. The analysis of the converter is carried out, and a design procedure is proposed. The design is also performed so that low capacitances are needed at the output of each semi-stage. This allows for the use of long-life film capacitors, thus matching the converter lifetime to that of the LED lamp. A laboratory prototype supplied from 230 Vrms/50 Hz mains used to drive two LED arrays in series with a total output power of 100 W is presented. [ABSTRACT FROM AUTHOR]

Although the natural permeability of rocks in the Asturian Central Coal Basin (NW Spain) is generally low, intensive mining activities over many decades has given rise to fracture flow paths that are far more permeable than those associated with the natural lithology. Abandoned and flooded mining works set up artificial 'pseudo-karst' aquifers, which can act as underground reservoirs, with many potential applications. In particular, a mining reservoir shaped by two connected mining shafts within the River Turón basin has been studied. A runoff model was used to produce accurate simulations of streamflow in three different gauging stations during a monitored period of 2 years. The purpose was to use this model in the forecast situation, in order to predict long-term situations in a hydrogeological FEFLOW model. It was necessary to develop depletion curves for each gauging station based on the available daily effective rainfall and measured flow data, as well as the knowledge of the basin characteristics. The resulting simulated hydrographs were very similar to the measured hydrographs during the monitored period, so the adequate adjusting allows input of the flow for forecast purposes. The model produced forecast hydrographs that had a r = 0.8 and difference in annual volume ranging from 1.6% to 5%. The defined model was applied to a rainfall data set of 30 years, and the average recharge from the river to the mining reservoir could be adequately estimated. The method developed needs to be refined and tested on additional years, but the approach appears to be applicable to operational runoff forecasting for numerical models input data. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]