closed-circuit

基本解释

There has been criticism that, like metal detectors, many closed-circuit cameras don't work or go unmonitored.
有人批评说，如金属探测器、许多闭路摄像机都不能正常工作或去监测。
The demand for access to the sentencing were so high that two additional rooms were provided for defrauded investors, media and spectators to watch on closed-circuit television.
由于要求出席审判的人太多，以至于不得不额外提供两个房间给受骗的投资人、媒体和观众去观看闭路电视。
But on Monday, journalists previously barred from the court property were permitted to watch the final proceedings by closed-circuit television from a courtroom annex.
但周一时，此前被禁止踏入法院的记者获准来到法院七层的一间屋子，通过闭路电视收看宣判的情景。

Lead surgeon Dr.Antonio Alcaraz instructs fellow surgeons and students watching the procedure through closed-circuit television.

The use of automated closed-circuit surveillance cameras is proving effective in deterring urban street crime.
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Chen said he heard Meng make the pledge at a conference carried on closed-circuit television.
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A closed-circuit television or video system is one that operates within a limited area such as a building.