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Anthropogenic gadolinium (Gd), used as a contrast agent in magnetic resonance imaging, may enter rivers and groundwaters with the effluents of wastewater treatment plant (WWTP). Such contaminations, which are mainly found in densely populated areas with highly developed medical systems, induce positive gadolinium anomalies in waters. This study reports on(More)
In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: Keywords: Karst aquifers Hydrograph recession Matrix–conduit exchange Hydrodynamics(More)
A fracture map is an essential aid in the study of fissured aquifers even though it often includes covered areas where the fractures are not visible. Is it possible to predict fracturing or permeable zones under the cover? This problem is dealt with using a stochastic approach based on fracture density. Classical methods of fracture density assessment(More)
Tracer tests represent the most appropriate approach for assessing hydrodispersive parameters such as transversal and longitudinal dispersivities or kinematic porosity on an aquifer scale. They are generally carried out by injecting a tracer in a borehole and measuring its concentration over time in neighboring boreholes by extracted volume sampling or(More)
The feasibility of flash flood prediction without rainfall forecasts nor previous discharge is considered. After a presentation of the important stakes involved in this task (23 fatalities in the Var event in June 2010, France) the important stage of variable and complexity selection is addressed for the small basin of Mialet (a part of the Gardon d'Anduze(More)
Neural networks are increasingly used in the field of hydrology due to their properties of parsimony and universal approximation with regard to nonlinear systems. Nevertheless, as a result of the non stationarity of natural variables (rainfalls and consequently discharges) it appeared as difficult to capture both dynamics (roughly slow and fast) in a same(More)
The ability of the multilayer perceptron to model the inverse relation of a fictitious watershed is investigated. Comparison is done between a new formulation of data assimilation and the standard multilayer perceptron applied to three kinds of models: static, feedforward and recurrent. It appears that both techniques are equivalent and allow a very good(More)
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