1. Department of Computer Science, Lille University, Cité Scientifique, 59650 Villeneuve-d’Ascq, France
2. BISITE Research Group, University of Salamanca, 37007 Salamanca, Spain
3. Air Institute, IoT Digital Innovation Hub, 37188 Salamanca, Spain
4. Department of Electronics, Information and Communication, Faculty of Engineering, Osaka Institute of Technology, Osaka 535-8585, Japan