Funding for this research was provided by:
National Natural Science Foundation of China (61790573)
National Natural Science Foundation of China (62073027)
Natural Science Foundation of Beijing Municipality (4192046)
State Key Laboratory of Rail Traffic Control and Safety (RCS2020ZZ003)
Article History
Received: 24 April 2020
Accepted: 22 October 2020
First Online: 3 November 2020
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.