Abstract: An air traffic control system which prevents a human air traffic controller from speaking directly with an aircraft crew, but which receives instructions from a human air traffic controller, understands their semantic meaning, integrates the semantic meaning of these instructions with specified parameters to maximize safety of the aircraft, and transmits them to the aircraft crew through a computer generated voice message.

Abstract: An improved roller press for the high pressure interparticle crushing of a pulverulent material and the method of operating including opposed parallel horizontal crushing rollers forming a high pressure crushing nip between them and forcing air from the material drawn into the nip, a product delivery stack above the nip and an offset lower wall portion above the nip and laterally of the stack forming an exposed sloping surface of the material for the escape of air being pressed out of the material passing into the nip, in one form exposed surfaces are on both sides of the nip and the exposed surfaces may be controlled by adjustable gates to vary the area and slope of the exposed surface, and a subatmospheric pressure may be applied to the material for aiding in the pressing of air from the material drawn into the nip.

Abstract: A high pressure roller press for interparticle crushing of material including opposed crushing rollers with at least one roller being movable, a gate controlled material feed to the nip of the rollers, means measuring the nip width by measuring the distance between bearings of the rollers, means measuring the nip force by measuring the hydraulic pressure applied to the movable roller to obtain nip force, a comparator receiving signals of nip width and nip force and having an output to maintain a linear relationship between nip width and nip force and controlling the feed to the nip and the nip width to maintain the relationship.