In this study, three-cup anemometers with wind vanes are insufficiently sensitive to measure the subway's light breezes and rapid pulsations. Therefore, we turned to ultrasonic anemometers to provide the instrumental qualities desired. Furthermore, ultrasonic anemometers offer additional measurement possibilities beyond conventional three-cup anemometers and wind vanes, including air temperature and density. The addition of a third orthogonal surface gives the vertical wind vector. Further advantages of sonics are as follows.
Mechanical anemometers have threshold friction and inertia.
Sonics however, have no threshold friction and inertia. For instance, sonics can detect human breathing at 2 meters. Prior to sonics, only the qualitative measures of smoke could begin to address this precision. Findings Please be a little patient.