Double Rollers Crusher is used to crush clunch and partial shales for brick enterprises. It has two rollers to circumrotate in reverse. The clunch between rollers are crushed by extrusion.
A semicomplete multipartite digraph is obtained by replacing each edge of a complete multipartite graph by an arc or by a pair of two mutually opposite arcs.
Fremen are able to use Maker Hooks to steer a sandworm by hooking into gaps in the sandworm's plating, forcing the creatures to instinctively move in the opposite direction.