Close loop security check

five-level security check

misoperation prevention security check

Security at sea

Security Check

Ship security check

accidents at road crossing

ammonia synthesis at at-mospheric pressure and low temperature

The road at the end of the grass-roots level

Data security and computer security

NSTISSC National Security Telecommunications and Information Systems Security Committee

water security and city water security

Web services security WS-security

check digit check

Check in and check out

check sum check

machine check and program check

AT tailing AT

global system for mobile communication AT (GSM AT ) command set