摘要 |
A simple trip-wire or magnetic circuit associated with a shipping container provides continuity, which is detected electrically. Simply, if continuity is disabled by a forced entry of the container, electrical detection means, such as a radio-frequency-identification (RFID) tag, will alert the owner or monitoring station. The trip-wire concept would require the replacing of a broken trip wire (resulting from forced entry), while the magnetic circuit concept can be reused repetitively. In a second embodiment, a magnetic circuit and the detection device (RFID tag) are embedded into the shipping article during manufacturing. The preferred detection device, an RFID tag, could also be a battery backed transceiver type on which a replaceable or rechargeable battery could be mounted on the inside of the shipping container during manufacturing. The RFID tag would communicate with an interrogator unit, which could be connected to a host computer. The interrogator and/or the host computer and/or other alarm devices would then monitor the shipping container's status (opened or closed).
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