1. Faculty of Engineering, School of Electronic, Electrical and Systems Engineering, Loughborough University, Leicestershire LE11 3TU, UK;
2. Department of Mechanical and Industrial Engineering, College of Engineering, Qatar University, Doha 2713, Qatar e-mail:
3. Faculty of Engineering, School of Electronic, Electrical and Systems Engineering, Loughborough University, Leicestershire LE11 3TU, UK
4. Department of Mechanical and Industrial Engineering, College of Engineering, Qatar University, Doha 2713, Qatar