Humidity-Sensitive PMMA Fiber Bragg Grating Sensor Probe for Soil Temperature and Moisture Measurement Based on Its Intrinsic Water Affinity. - Heng Wang; Shixin Gao; Xiaoyu Yue; Xin Cheng; Qi Liu 039; Rui Min; Hang Qu; Xuehao Hu (Sensors, 2021)