MODELING OF COLLABORATIVE PRODUCTION SYSTEMS USING COLOURED PETRI NETS Topics: Ambient Intelligence; Context-Aware Applications; Mobile Computing; Pervasive Embedded Networks; Ubiquitous Computing Systems and Services In Proceedings of the 1st International Conference on Pervasive and Embedded Computing and Communication Systems PECCS - Volume 1, 257-260, 2011 , Vilamoura, Algarve, Portugal