Funding for this research was provided by:
National Natural Science Foundation of China (61170305, 61672024)
Directorate for Computer and Information Science and Engineering (CMMI-1162482)
Henan Provincial Department of Education (17A520046)
Article History
First Online: 13 July 2018
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest.
: This article does not contain any studies with human participants performed by any of the authors.
: Informed consent was obtained from all individual participants included in the study.