Funding for this research was provided by:
National Natural Science Foundation of China (61501327)
Natural Science Foundation of Tianjin City (15JCQNJC01700, 17JCZDJC30600)
National Laboratory of Pattern Recognition (201800002)
China Scholarship Council (201708120039)
Text and Data Mining valid from 2018-02-27
Received: 18 January 2018
Accepted: 20 February 2018
First Online: 27 February 2018
: The authors declare that they have no competing interests.
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