When the system determines visitors to acquaintances (in safety case), do not produce alarm, otherwise select and create alert.

当系统判定访客为熟人(即安全情况)时，不产生报警，反之则产生报警。

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For instance, the company is currently assembling a list of certified businesses to create an alert system that distinguishes between phishing sites and legitimate sites.

FORBES: Spear The Phishers--Not The Fish

Agency officials said, however, that they were alarmed enough that they immediately ordered the companies that manufacture the meters to create a system to alert riders when the higher rates are being charged.

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Since this elaborate electronic hoax is an embarrassment to the university at a level, will athletic departments create red flag words and phrases that alert the school of illicit conversations and then monitor player electronic communications like cell phone and computer data?

FORBES: Who's Been Duped? The Manti Te'o Hoax.