**Author details**

Ronald Nguele1 \*, Katia Nchimi Nono2 and Kyuro Sasaki1

1 Kyushu University, Fukuoka, Japan

2 University of Yaoundé I, Cameroon

\*Address all correspondence to: nguele@mine.kyushu-u.ac.jp

© 2021 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
