Abstract: A material tracking and management system is disclosed, which comprises multi electronic tags respectively connected to containers, a first electronic device, and a second electronic device. After the containers are placed in a storage environment, the first electronic device accesses each electronic tag to acquire a cold storage condition for the material accommodated in the container, and detects an ambient temperature of the storage environment through a temperature sensor. As a result, the first electronic device calculates an adjustment parameter for adjusting the expiration date based on the ambient temperature and the cold storage condition. After the container is transported to a user environment, the second electronic device accesses the electronic tag to acquire the adjustment parameter and a regular expiration date, thereby adjusting the regular expiration date to an instant expiration date.

Abstract: An encryption method applied to an encryption system is disclosed. The encryption system includes a transmission module, an encryption module and a memory. The memory contains n data, where n is an integer and n?0, and the n data are encrypted by the encryption module. The multiple encryption method includes: via the transmission module, receiving an encryption request and an n+1th data; storing the n+1th data in the memory; via the encryption module, according to the encryption request, encrypting the n data and the n+1th data to form an encrypted data.