**Author details**

Tao Han1 and Andrea Cavallini2 \*

1 School of Electrical and Information Engineering, Tianjin University, Tianjin, China

2 University of Bologna, Bologna, Italy

\*Address all correspondence to: andrea.cavallini@unibo.it

© 2020 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.
