Who sent the text message accompanying time and space?

Chengdu's original "space-time companionship" cannot be used as a national epidemic prevention model. If it is base station positioning, it is expanding the killing range. What I found is the positioning accuracy of 100 meters. That is to say, if your family lives there, then someone drives over and gets stuck in traffic. Is that a large number of people are yellow. If it is gps positioning, it means that your trip is monitored in real time. Where is the data source? This is a complete abuse of technology. This method is bound to increase the workload on the basis of controllability.

Time-space companion means that my phone number and confirmation number stay together for more than 10 minute in the same time-space grid (the range is 800M*800M), and the cumulative stay time of any number in the last 14 days exceeds 30 hours, and the found number is the time-space companion number. My green health code will turn into a yellow code with warning nature, and will be marked as "time companion" by the system.

For example, the infected person has been to a certain place within 14 days, and the trajectory of you 14 days intersects with him. Whether it is a physical passing or a drift in communication signals, it may be considered as a "time companion."

What should a "space-time companion" do:

Persons with yellow health code and persons at risk associated with time and space who have received SMS reminders from Chengdu Public Security Bureau and Municipal Center for Disease Control and Prevention should immediately report to the community, and conduct two nucleic acid tests within 3 days, with the interval between the two nucleic acid tests being more than 24 hours. Please stay at home and don't go out until you get a negative result of nucleic acid.

It can be seen that "time-space accompaniment" is a risk definition based on the comprehensive utilization of big data and various information resources, which accurately arranges the trajectory of confirmed cases and comprehensively combs the people who overlap with confirmed cases.

Taking Chengdu as an example, it was found that after the emergence of local cases in COVID-19, a total of 82,000 people were at risk in time and space.