Funding for this research was provided by:
National Natural Science Foundation of China (51704177)
A Project of Shandong Province Higher Educational Science and Technology Program (J16LG04)
Doctoral Research Fund of Shandong Jianzhu University (XNBS1501)
Article History
Received: 22 December 2017
Accepted: 26 March 2019
First Online: 12 April 2019
Compliance with Ethical Standards
:
: The authors declare that they have no conflict of interest.