1. Environment and Remote Sensing Research (EARTH) Laboratory, Physics Department, College of Science, De La Salle University Manila, 2401 Taft Avenue, Manila 0922, Philippines
2. Division of Physical Sciences and Mathematics, College of Arts and Sciences, University of the Philippines Visayas-Miagao Campus, Miagao 5023, Philippines
3. Graduate School of Engineering, Chiba University, Yayoi-cho, Chiba-shi 263-8522, Japan