Funding for this research was provided by:
Science and Technology Plan Project of Beijing (No. Z171100005117001)
Beijing Outstanding Talent Training Foundation (No. 2017000021063G008)
National Engineering Laboratory for Comprehensive Transportation Big Data Application Technology
Article History
First Online: 20 April 2019
Compliance with ethical standards
:
: All authors declare that they have no conflict of interest in this research.
: This article does not contain any studies with human participants or animals performed by any of the authors.
: Informed consent was obtained from all individual participants included in the study.