The optical fiber sensor is a kind of device which can monitor change of external environment by testing the characteristics of light. It is based on light transmission in fiber.

光纤传感器是根据光纤的传输原理，通过对光纤传光特性的检测来感测外部环境变化的一种装置。

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We simply don't have historical records to monitor change on a broad scale.

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In the face of these accelerating physical, biological and social transformations, there is a need to monitor change, assess impacts and mobilize responses so as to adequately inform adaptation policies and practice.

UNESCO: Global Change in the Arctic and Co-production of Knowledge

He stressed that the investigation is continuing and the bus monitor could change her mind.

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