Funding for this research was provided by:
Key Supported Discipline of Guizhou Provence (ZDXK [2018]007)
Key Disciplines of Guizhou Province - Computer Science and Technology (ZDXK [2018]007)
Guizhou Provincial Service Industry Development Guide fund project in 2018 (No.QianFaGaiFuWu[2018]1181)
Key Supported Disciplines of Guizhou Province - Computer Application Technology (No.QianXueWeiHeZi ZDXK[2016]20)
Article History
Received: 16 January 2020
Accepted: 22 April 2020
First Online: 7 May 2020
Competing interests
: The authors declare that they have no competing interests.