Yang, Yi https://orcid.org/0000-0001-9964-3492
Meng, Guanfei
Funding for this research was provided by:
National Social Science Foundation of China Western Project (15XJL009)
Soft Science Research Program of Shaanxi-Joint Project (2018KRLY07)
Article History
Received: 28 March 2019
Accepted: 9 December 2019
First Online: 26 December 2019
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.