1. Department of Economic Management, Guangdong Vocational and Technical College of Posts and Telecom, No. 191 of Zhongshan Rd., Guangzhou 510000, China (Corresponding author), e-mail: yvonnesy@163.com, https://orcid.org/0000-0002-2458-3090
2. School of Mobile Communication, Guangdong Vocational and Technical College of Posts and Telecom, No. 191 of Zhongshan Rd., Guangzhou 510000, China