[1] Sapienza Univ Rome, Dept Comp Control & Management Engn, Rome, Italy
[2] Univ Aquila, Dept Ind & Informat Engn & Econ, Laquila, Italy
[3] Politecn Milan, Dept Management Econ & Ind Engn, Milan, Italy
[4] Univ Aquila, Dept Ind & Informat Engn & Econ, I-67100 Laquila, Italy