They made a film record of the experiment using hidden cameras.

他们用隐蔽摄像机制作了一部该实验的记录电影。

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Two hidden cameras then look for the 'glints' from eyeballs and reflections from each retina.

两个隐蔽的照相机来获取用户眼球中的“闪耀”之处以及视网膜的反应。

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Once released, the cub will be closely monitored through hidden cameras to ensure its safety.

放养后，熊猫幼崽会被隐藏的摄像机密切监测，以确保它的安全。

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In the last census, forest officials used more scientific methods, including hidden cameras and DNA tests.

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Hidden cameras are associated with net falls in speeds, crashes and casualties when compared with visible ones.

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They come to him to install surveillance camera systems and perform sweeps for hidden cameras and bugs.

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