UTC Universal Time Coordinated. This is Greenwich Mean Time, adjusted to be an integral number of seconds different from International Atomic Time.
格林尼治（平均）时坐标。这是格林尼治平均时，被调整到秒的整数值，它异于国际原子时。（参考）
2
The "atomic" algorithm performs decoding process using Fourier transformation only once and the integral Fourier transformation works without floating operation.