Funding for this research was provided by:
Guang Dong Provincial Natural fund project (2016A030310300)
the Ministry of Education in China Project of Humanities and Social Sciences (18YJAZH137)
National Natural Science Foundation of China-Yunnan Joint Fund (71401045)
the Guangdong Provincial Natural Fund Project (2017A030313394)
major scientific research projects of Guangdong (2017WTSCX021)
the planning project of the 13th Five-Year in Philosophy and Social Sciences of Guangzhou (2018GZGJ48)
Ministry of Education Science and Technology Development Center (2017A11001)
Guangdong Science and Technology Key Project (2015B010131009)
Article History
Received: 3 January 2019
Accepted: 7 August 2019
First Online: 19 August 2019
Compliance with ethical standards
:
: The authors declare that they have no conflict of interest regarding the publication of this paper.