Published on in Vol 8, No 7 (2020): July
Preprints (earlier versions) of this paper are
available at
https://preprints.jmir.org/preprint/17958, first published
.
1 School of Communication, Shenzhen University, Shenzhen, China
2 Department of Computer Science, Harbin Institute of Technology Shenzhen Graduate School, Shenzhen, China
3 Yidu Cloud (Beijing) Technology Co Ltd, Beijing, China
*these authors contributed equally