https://hal-univ-poitiers.archives-ouvertes.fr/hal-01941518 Contributor : Abderrazak HALLOUMIConnect in order to contact the contributor Submitted on : Saturday, December 1, 2018 - 1:43:12 PM Last modification on : Wednesday, October 20, 2021 - 3:22:16 AM Long-term archiving on: : Saturday, March 2, 2019 - 12:56:08 PM