In {TAIL ~ such an arrangement}, {HEAD ~ the air} from the interior of the indoor institution is introduced into the cyclone wherein dust in the air is removed 
In { TAIL ~ such an arrangement } , { HEAD ~ the air } from the interior of the indoor institution is introduced into the cyclone wherein dust in the air is removed
REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH