On May 20, Zhan Wenlong, Deputy President of Chinese Academy of Sciences (CAS), visited National Time Service Center (NTSC) for survey. Guo Ji, Wang Yulin, Dou Zhong, Lu Xiaochun and all Research Directors from NTSC attended the symposium. On the symposium, Dou Zhong firstly gave a detailed report on progress of major special projects of NTSC. Soon after, Lu Xiaochun made a specific report on enhancement of Big Dipper wide area and Guo Ji reported the construction of China time-frequency system to Zhan Wenlong.

After listening to the reports, Zhan Wenlong fully affirmed the achievements obtained by NTSC in recent years. Then, he visited the Big Dipper Calibration Station and Quantum Frequency Standards Lab. of NTSC and listened to the work description introduced by relevant researchers.