Reenement and abstraction are essential operations used in the design of actual systems, real-time or not. We generalize these concepts to sequences of timed actions which are widely used as semantics of real-time behaviors. We obtain two natural, but quite diierent, notions of reenement and abstraction for timed languages depending on whether a timed action is regarded as an action with a dura...

At ASIACRYPT 2012, Petit and Quisquater suggested that there may be a subexponential-time index-calculus type algorithm for the Elliptic Curve Discrete Logarithm Problem (ECDLP) in characteristic two fields. This algorithm uses Semaev polynomials and Weil Descent to create a system of polynomial equations that subsequently is to be solved with Gröbner basis methods. Its analysis is based on heu...

Different approaches to construct linear codes using skew polynomials can be unified by using the nonassociative algebras built from skew-polynomial rings by Petit.

This documentation describes the PCC(FD) library v.0. that can be downloaded from http://www.irisa.fr/lande/petit/index.en.html. The library has been built upon SICStus 3.11.0 [2].