“…Tags could detect changes in movement, stress, strain, vibration, tilt, etc., often to control the state of a structure, as varied as that may be (tightening of a screw, building, aircraft wing) [ 43 , 44 , 45 , 46 , 47 ], humidity, temperature, moisture [ 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 ], corrosion and chemicals [ 56 , 57 , 58 , 59 , 60 ], and also pressure, light level, audible feedback, or biometric data, etc. Note that most of these measures can be absolute or relative, for example, to detect the passage of a threshold.…”