Yuan, Yueding http://orcid.org/0000-0002-9020-8686
Chen, Haibo
Funding for this research was provided by:
National Natural Science Foundation of China (11561068, 11671403)
China Postdoctoral Science Foundation (2016M592442)
Mathematics and Interdisciplinary Science Project of CSU
Article History
Received: 23 October 2017
Accepted: 16 January 2018
First Online: 13 February 2018
Competing interests
: The authors declare that they have no competing interests.