The query results of communication big data travel cards show that the provinces and cities (domestic), countries and regions (international) are divided into three types: green card, Huang Ka card and red card, and the rules will be adjusted in real time according to the actual situation. The user's travel calculation for the first 14 days was completed in the background of the operator, resulting in a one-day delay.
In addition, because the service uses base station data, in order to ensure continuous communication and achieve no blind area coverage, the base station signals at the junction of administrative divisions may cross-cover, resulting in deviation of the results, so it can be adjusted according to other certificates.
Extended data
Travel cards use Bluetooth signal strength to judge the distance between users and others, and contact records will be encrypted and stored in users' mobile phones. If no one is infected with COVID-19 during use, the data will be cleared automatically after 2 1 day (the time will be adjusted in real time according to the prevention and control requirements).
Once a user is diagnosed as a confirmed/suspected patient in COVID-19, the epidemic prevention department will ask him to upload the contact record information in his mobile phone, so as to help epidemic prevention and control personnel find close contacts more quickly and remind him to observe and isolate in time.
Baidu Encyclopedia-Communication Big Data Travel Card
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