A pneumatic aerator aids in bulk material unloading, handling and transport using tank trailers, hopper cars, and other containers, as its aerator introduces a cyclonic air flow and vibration into the bulk material. A host’s scarcity for a parameter may be determined by multiplying the host’s capacity for a parameter with the overall scarcity of that parameter. An isolation bottom layer and a polysilicon layer are orderly disposed on the substrate between the first and the second isolation walls.