TY - Computer Engineering and Applications A1 - LI Chaoqun, CHEN Zhigang, SONG Xinxia, ZHOU Yunhui T1 - Survey of Contact Tracking System in Epidemic Environments Y1 - 2021-05-01 JF - Computer Engineering and Applications JO - Computer Engineering and Applications SP - 68 EP - 80 VL - 57 IS - 9 UR - http://cea.ceaj.org N1 - 10.3778/j.issn.1002-8331.2101-0199 ER -