Abstract: Processing circuitry is configured to obtain a data structure that defines a plurality of conversions of data between pairs of fields; perform a search to identify a plurality of paths from a source node of the data structure to a destination node of the data structure, wherein the source node corresponds to a first field of the fields and the destination node corresponds to a second field of the fields; convert, for each path of the plurality of paths, transforms represented by corresponding edges of the path to a sequence of transforms that conform to a solver format; process the sequence of transforms for each path to determine whether all paths of the plurality of paths are equivalent up to an equivalence relation; and output an indication of whether all paths of the plurality of paths are equivalent up to an equivalence relation.

Abstract: A control system for controlling abrasive blasting apparatus and an abrasive blasting apparatus including such a control system. The control system controls delivery of air and blast media to a blast nozzle of the abrasive blasting apparatus. The control system includes a deadman's switch, the deadman's switch features a user operable control. The user operable control is moveable from a first position, where the control system causes the abrasive blasting apparatus to not deliver air or blast media, to a second position where the control system causes the abrasive blasting apparatus to deliver both air and blast media. When the user operable control is in an intermediate position between the first and second positions, the control system causes the abrasive blasting apparatus to deliver air but not blast media. The control system may have control elements whose state may be sequentially changed by the user operable control as it moves.