Aiming at the tedious maintenance work of ac filament conversion relay of railway signal lamp unit, this paper designs a new online detection device for relay working state. By switching relay paths ...

In this paper, the weighted fractional Fourier transform (WFRFT) signal domain is introduced to enhance the security performance of two-way trusted relay systems at the signal level. The proposed ...

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A NASA satellite that’s been orbiting as space junk since 1967, Relay 2, emitted an unexpected, powerful radio burst that astronomers initially struggled to explain.