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Yiannis Tsapras Rachel A. Street Keith Horne Alan Penny Fraser Clarke Hans Deeg Francisco Garzon Simon Kemp Maria Rosa Zapatero Osorio Alejandro Oscoz Abad Santiago Madruga Sanchez Carlos Eiroa Alcione Mora Antxon Alberdi rew Cameron John K. Davies Roger Ferlet Carol Grady Allan W. Harris Javier Palacios reas Quirrenbach Heike Rauer Jean Schneider Dolf de Winter Bruno Merin Enrique Solano 《Monthly notices of the Royal Astronomical Society》2001,325(3):1205-1212
In 1998 the EXPORT team monitored microlensing event light curves using a charge-coupled device (CCD) camera on the IAC 0.8-m telescope on Tenerife to evaluate the prospect of using northern telescopes to find microlens anomalies that reveal planets orbiting the lens stars. The high airmass and more limited time available for observations of Galactic bulge sources make a northern site less favourable for microlensing planet searches. However, there are potentially a large number of northern 1-m class telescopes that could devote a few hours per night to monitor ongoing microlensing events. Our IAC observations indicate that accuracies sufficient to detect planets can be achieved despite the higher airmass. 相似文献
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Groundwater recharge and discharge define the relationships among groundwater storage, precipitation, evapotranspiration, and surface water. Understanding and quantifying groundwater recharge and discharge is crucial for developing effective management options for water supply. Traditional recharge and discharge studies usually require time-consuming (months or years) and labor-intensive field characterization. Therefore, a fast initial recharge and discharge estimation will help scientists and decision makers design more accurate and cost-effective research plans and management strategies. A new GIS based methodology along with an ArcMap plug-in package, PRO-GRADE, was developed to help hydrogeologists estimate recharge and discharge in a more efficient way than conventional methods. The Groundwater Recharge And Discharge Estimator (GRADE-GIS) in the PRO-GRADE package uses a mass balance approach for steady state two-dimensional unconfined aquifers. GRADE-GIS only requires relatively short preparation time (hours) using readily available data for water table and bedrock elevations, and hydraulic conductivities. The Pattern Recognition Organizer (PRO-GIS) in the PRO-GRADE package uses multiple image processing algorithms to estimate and visualize shallow recharge and discharge patterns and rates with GIS. The output of PRO-GRADE can be used as an initial guideline for conventional field study planning and decision making, or an initial condition for numerical simulations. 相似文献
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