Dr. Gregorio Romero Rey (Spain, 1974) received his Industrial Technical Engineering degree from the ICAI in 1996 and his Mechanical Engineering degree from the UNED in 2000. After the analysis of mathematical systems corresponding to multi-domain models, he was awarded his PhD Degree by the Universidad Politécnica de Madrid in 2005, the university in which he works as Associated Professor. Since 1997, he has worked mainly on simulation models and the virtual reality area, developing his research activity in the Research Group in Railway Technology and Advanced Simulation (CITEF) collaborating on European and National Projects, apart from works with private companies. He has been involved in different technical committees and has received two prizes associated with his research and education activity. At present he is the manager of an electrical simulator designed for a Spanish company and has published more than 70 technical papers in different international journals, books and conferences.