Funding for this research was provided by:
National Natural Science Foundation of China (51571152)
Key Scientific Program of Higher Education of He’nan Province of China (17B430006)
He’nan Provincial Training Program of Innovation and Entrepreneurship for Undergraduates (201713503002)
Xinyang College Training Program of Innovation and Entrepreneurship for Undergraduates (CX20170003)
Article History
Received: 30 April 2018
Accepted: 27 August 2018
First Online: 31 August 2018