[1
]Politecnico di Bari, Department of Mechanics, Mathematics and Management, Viale Japigia
182, 70126 Bari, Italy
[2
]Department of Mechanical Engineering, Hamburg University of Technology, Am Schwarzenberg-Campus
1, 21073 Hamburg, Germany
[3
]Department of Mechanical Engineering, University of Michigan, Ann Arbor, MI 48109-2125,
USA