When circumjacent load makes the lowest natural frequency zero, critical load is obtained.

当周边面力使夹层圆板的最低固有频率为零时，就可获得临界载荷的值。

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The ability to deliver the work on the part of the employer disappears because the critical difference between an ordinary employment contract and a zero hours contract is the legal concept mentioned earlier of "mutuality of obligation".

BBC: Zero hours contracts for NHS staff explained

The most critical decision that the OIC made in Mecca was to adopt a zero-tolerance policy toward perceived insults to Islam.

CENTERFORSECURITYPOLICY: Center For Security Policy