1. Department of Physics, Universitas Brawijaya Malang, Malang, Indonesia
2. Department of Electrical Engineering, State Polytechnic of Malang, Malang, Indonesia
3. Department of Informatics Engineering, Universitas Islam Negeri Maulana Malik Ibrahim Malang, Malang, Indonesia
4. Department of Electrical Engineering, Universitas Brawijaya, Malang, Indonesia
5. Department of Geophysical Engineering, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia
6. Department of Physics, Universitas Pertahanan Republik Indonesia, Bogor, Indonesia
7. School of Business, Social and Decision Science, Constructor University, Bremen, Germany