stopping the swiveling of the nacelle by the nacelle swiveling mechanism when the wind speed obtained from the measurement result of {TAIL ~ the anemometer} is not greater than {HEAD ~ the first threshold} 
stopping the swiveling of the nacelle by the nacelle swiveling mechanism when the wind speed obtained from the measurement result of { TAIL ~ the anemometer } is not greater than { HEAD ~ the first threshold }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD