Funding for this research was provided by:
National Natural Science Foundation of China (31302127)
Natural Science Foundation of Heilongjiang Province (C2016028)
the National key research and development plan project (2016YFD0500904)
Fund of Heilongjiang Province Education Department (12541003)
Text and Data Mining valid from 2018-07-28
Received: 12 June 2017
Accepted: 28 June 2018
First Online: 28 July 2018
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