Liu, Shuang
Li, Mei
Funding for this research was provided by:
National Natural Science Foundation of China (61501327)
Natural Science Foundation of Tianjin City (17JCZDJC30600)
Natural Science Foundation of Tianjin City (15JCQNJC01700)
National Laboratory of Pattern Recognition (201800002)
Scholarship Council of China (201708120039)
Article History
Received: 18 January 2018
Accepted: 20 February 2018
First Online: 27 February 2018
Competing interests
: The authors declare that they have no competing interests.
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