Len Gelman, PhD, Dr. of Sciences (Habilitation), Professor, Chair in Signal Processing/Condition Monitoring and Director of the Centre for Efficiency and Performance Engineering, University of Huddersfield, UK Len has published more than 250 publications and 17 patents and is the Co-Editor of 12 Springer books. Len is an Editorial Board member of MDPI journals "Applied Sciences", Electronics”, “Sensors”, and “Energies”. He is a Fellow of the British Institute of NDT and the International Association of Engineers and Institution of Diagnostic Engineers, Executive Director of the International Society for Condition Monitoring, Editor-in-Chief of the International Journal of Engineering Sciences (SCMR), Chair of International CM Groups of ICNDT and EFNDT, and a Member of the ISO Technical Committee, Condition Monitoring.