Funding for this research was provided by:
China Scholarship Council (201606690017)
National Natural Science Foundation of China (51505116)
the army aviation equipment ”13th Five-Year” special research project (30103090201)
Article History
Received: 21 May 2018
Accepted: 7 December 2018
First Online: 17 December 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.