A Fiber Bragg Grating-Based Condition Monitoring and Early Damage Detection System for the Structural Safety of Underground Coal Mines Using the Internet of Things

<div>(a) FBG arrays attached to the mine roof. (b) Visual aspect of the FBG strain sensor array. (c) Schematic of the FBG strain sensor arrays.</div>

Journal of Sensors

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Figure 7

Figure 7: A Fiber Bragg Grating-Based Condition Monitoring and Early Damage Detection System for the Structural Safety of Underground Coal Mines Using the Internet of Things 

Figure 7 | A Fiber Bragg Grating-Based Condition Monitoring and Early Damage Detection System for the Structural Safety of Underground Coal Mines Using the Internet of Things 