motion detector


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motion detector

A device to detect intrusion within an area to be protected. The device radiates waves (electromagnetic or ultrasonic, at a fixed frequency) that are reflected back to the device. If an intruder moves within the protected space, a change in frequency results which is detected and which activates an alarm.
References in periodicals archive ?
Nokia Remote Camera is a wireless home monitoring system with an integrated motion detector.
Or they open a door to let the dog out, forgetting that the alarm is on, or leave a motion detector on with an animal in the house.
You'll need an infra-red webcam for capturing those paranormal apparitions, a motion detector to sound an alarm if ghostly movement is sensed and a Magnetic Field meter for when there's _ a disturbance in the force.
Since the boy from Suita, Osaka Prefecture, was 117 centimeters tall, police suspect a motion detector in the door's ceiling was not set at its maximum range of 80 cm from the floor, and the blind spot was not minimized.
The Long Gun Vault has a sensitivity adjustable motion detector with audible alarm, and a Security Sleep Mode that disables the keypad after 24 incorrect entries.
Soldiers and security guards in the market for better sensors may be interested in a new motion detector that sees through concrete walls.
Other features include a motion detector with user-adjustable sensitivity, an audible alarm activated by the unit's motion detector and a "Security Sleep Mode" that disables the keypad after 24 incorrect entries.
Robert and Gopfert used a laser-based motion detector to track minute vibrations in the arista and the two-part oblong base of a Drosophila antenna.
TM] incorporates a state-of-the-art digital processor that runs all functions; a built-in motion detector, a weather-tight housing with Natgear(R) camo, and a Yashica T4 Super 35mm camera with a Zeiss(R) lens.
Closed circuit television cameras can be adjusted to automatically lock on an area when a motion detector is tripped, such as in a stairwell, or when a 'scream' alert is set off in an elevator.
For example, if a motion detector alarm system goes off accidentally in an airport, it's likely the user will be too embarrassed to use it in the future.
Even if this motion detector business is mature, it will continue to grow at a significant rate (CAGR 2010-2016 in value: 9%) driven by the concern for energy savings.