1. a Department of Applied Physics , University of Athens , Panepistimiopolis Build. Phys. 5, 15784, Athens, Greece
2. b Division of Electronic Engineering and Physics , University of Dundee , Dundee DD1 4HN, UK
3. c Department of Remote Sensing , Faculty of Geoinformation Science and Engineering , Universiti Teknologi Malaysia , 81310 UM Skudai, Johor, Malaysia
4. d Department of Energy Technology , Technological Education Institute of Athens , Ag. Spyridonos Str., 12210, Athens, Greece
5. e Department of Electronics , Technological Education Institute of Piraeus , Thivon 250 & P. Ralli, Aigaleo‐12244, Greece
6. f Ministry of Environment , Directorate of Air and Noise Pollution Control , 147, Patission str., 11251 Athens, Greece