1. Doctoral School Materials Science and Engineering, National University of Science and Technology Politehnica Bucharest, Splaiul Independentei, no. 313, Sector 6, Bucharest, Romania
2. Pitești University Centre, Facu lty of E lectronics, Communication and Computers, National University of Science and Technology Politehnica Bucharest , Targu din Vale, no.1, Pitesti, Romania
3. Pitești University Centre, Facu lty of Mechanics and Technology, National University of Science and Technology Politehnica Bucharest, Targu din Vale, no.1, Pitesti, Romania