Funding for this research was provided by:
National Natural Science Foundation of China (61774021)
ational Natural Science Foundation of China (61504010)
Fund of State Key Laboratory of Information Photonics and Optical Communications (IPOC2017ZT02)
Science & Technology program of Guangzhou Education Municipality (1201630328)
Text and Data Mining valid from 2018-07-31
Received: 21 June 2018
Accepted: 24 July 2018
First Online: 31 July 2018
: WW (associate professor) and JQ (associate professor) are from School of Mechanical and Electric Engineering, Guangzhou University, China.XY (lecturer) and XZ (professor) are from State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100,876, China.BS (senior scientist) is from 4catalyzer Inc., 530 Old Whitfield St, Guilford 06437, CT, USA.
: The authors declare that they have no competing interests.
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