1. Mechanical Engineering Department, University of Las Palmas de Gran Canaria , Las Palmas de Gran Canaria , Spain
2. Materials Engineering and Welding Department, Transylvania University of Brasov , Brasov , Romania
3. Research Institute for Renewable Energy, Politehnica University Timisoara , Timisoara , Romania
4. Law Department, Faculty of Law, Transylvania University of Brasov , Brasov , Romania
5. Processes Engineering Department, University of Las Palmas de Gran Canaria , Las Palmas de Gran Canaria , Spain