There were 15 minutes between the first air raid alert and the sounding of the all-clear signal.

从第一个空袭警报到警报解除号音其间有15分钟。

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If they detect something wrong while the system is armed, they'll transmit a wireless alert signal to a base station that will then raise the alarm.

如果他们在系统布防时发现了什么问题，就会向基站发送无线警报信号，然后基站会发出警报。

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With the right device tuned to the right frequency, what's to stop a thief from jamming your setup and blocking that alert signal from ever reaching the base station?

通过将正确的设备调整到正确的频率，如何防止小偷干扰你的设备阻止警报信号到达基站呢？

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"This change to a higher phase of alert is a signal to governments, to ministries of health and other ministries, to the pharmaceutical industry and the business community that certain actions should now be undertaken with increased urgency, and at an accelerated pace,"

VOA: standard.2009.04.29

If said player gets dangerously close to colliding with an object, the safety system would signal an audible warning alert and pause the game.

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"This change to a higher phase of alert is a signal to governments, to ministries of health and other ministries, to the pharm industry and the business community that certain actions now should be taken with increased urgency and at an accelerated pace, " Chan said.

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That system, like most cars equipped with lane departure warning, uses a loud audible signal and a dashboard icon to alert you of the transgression.

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