They actually monitor the movement of the fish going up river.

他们实际上在观测鱼向上游的迁移活动。

《柯林斯英汉双解大词典》

This has prompted engineers to devise active dampers that use sensors to monitor the building's movement and powered actuators to respond accordingly by moving weights placed on the upper floors.

这问题促使工程师们设计出利用传感器监测建筑物运动的有源阻尼器，和照着定位在上层楼面的移重而回应的动力促动器。

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This has prompted engineers to devise active dampers that use sensors to monitor the building’s movement and powered actuators to respond accordingly by moving weights placed on the upper floors.

这问题促使工程师们设计出利用传感器监测建筑物运动的有源阻尼器，和照着定位在上层楼面的移重而回应的动力促动器。

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Cao Gadgets is attempting to fill that niche with its functionally named Wireless Sensor Tags -- small devices which monitor movement and temperature, notifying you if anything's amiss.

ENGADGET: Wireless Sensor Tags alert you to movement and temperature changes, fit on your keyring

With binoculars you can monitor every movement on the Ethiopian side - including Dongolo hill, which I had visited with the Ethiopian army.

BBC: De-mining in the Horn

Telford and Wrekin council said it was drilling bore holes between the Jackfield tile museum and the Boat Inn to monitor the movement of the land.

BBC: Ironbridge Gorge stabilisation work starts