1. Department of Industrial and Information Engineering and Economics, University of L'Aquila, L'Aquila, Italy
2. Materials and Mechanical Engineering, University of Oulu, Oulu, Finland
3. School of Energy Systems, Lappeenranta–Lahti University of Technology, Lappeenranta, Finland
4. Department of Mechanical Engineering, Lappeenranta–Lahti University of Technology LUT, Lappeenranta, Finland