Other ways of preventing crime include sensors which can detect or measure changes in the environment,such as movement,shock,smoke,etc. Cameras can be used to monitor an area continually. If the picture changes,an alarm sounds. The cameras can be turned and moved up and down by an operator,sometimes many kilometres away.
Other ways of preventing crime include sensors which can detect or measure changes in the environment,such as movement,shock,smoke,etc. Cameras can be used to monitor an area continually. If the picture changes,an alarm sounds. The cameras can be turned and moved up and down by an operator,sometimes many kilometres away.
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