Funding for this research was provided by:
National Natural Science Foundation of China (31771595, 31701244)
Fundamental Research Funds for the Central Universities (22120180549, 20002150001)
Natural Science Fund of Hebei Province of China (C2018209119)
Scientific and Technological Research Project of Higher Education of Hebei Province (BJ2019040)
Doctoral Scientific Research Foundation of North China University of Science and Technology (BS2017063)
Text and Data Mining valid from 2020-03-10
Received: 1 November 2019
Accepted: 29 February 2020
First Online: 10 March 2020
Ethics approval and consent to participate
: Not applicable.
: All authors have read and agreed to the final version of the manuscript.
: The authors declare that they have no competing interests.