Funding for this research was provided by:
Open project of Guangxi Key Lab. of Crypto. and Info. Security (GCIS201622, GCIS201621)
National Natural Science Foundation of China (61772150, 61262008)
Article History
First Online: 6 November 2017
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest with any individual or organization.
: This article does not contain any studies with human participants or animals performed by any of the authors.
: Informed consent was obtained from all individual participants included in the study.