1. IFAC-CNR, Nello Carrara Institute of Applied Physics, Via Madonna del Piano 10, Sesto Fiorentino 50019, Italy
2. DIEF, Department of Industrial Engineering, University of Florence, via di S. Marta 3, Firenze 50139, Italy
3. ISC-CNR, Institute for Complex Sistems, Via Madonna del Piano 10, Sesto Fiorentino 50019, Italy
4. Enrico Fermi Centre, Piazza del Viminale 1, Roma 00184, Italy