First Author:   Philippe Darreau LAPE, University of Limoges philippe.darreau@unilim.fr   5, rue Félix Eboué Limoges, F-87031, FRANCE   +33-(0)5-55-14-92-15(Phone) +33-(0)5-55-14-92-15(Fax) Second Author: François Pigalle LAPE, University of Limoges francois.pigalle@unilim.fr   Limoges, 87031, FRANCE   +33-(0)5-55-14-92-15(Phone)