detecting

Detecting Motion Circuit alarms are very effective for guarding the perimeter of a house, but they don't work so well inside a building. This is because the intruder's actions are highly unpredictable -- you don't know where they'll go or what they'll touch. A specific "trigger" isn't very...

Beijing: All airports in China will be installed with liquid detecting scanners before the 2008 Beijing Olympics, a report said on Friday. “All civil airports will be required to install at least one such scanner starting from next year,” head of the public security division under the General...