Funding for this research was provided by:
National Natural Science Foundation of China (61672130, 61602082)
The Open Program of State Key Laboratory of Software Architecture (SKLSAOP1701)
National Natural Science Foundation of China (61370200)
Article History
Received: 18 October 2017
Accepted: 19 November 2018
First Online: 4 January 2019
Compliance with ethical standards
:
: Yang Liu, Lin Feng, Shenglan Liu and Muxin Sun declare that they have no conflict of interest.
: This article does not contain any studies with human participants or animals performed by any of the authors.