Fuel injection apparatus comprising a solenoid coil ; an armature coupled with a valve element operable to open and close a fuel valve when the solenoid coil is selectively energized and de-energised. The data in the database is separated into one or more buckets and at least two replicas of each bucket of data are stored in different storage devices of the nodes. A method of producing a cable comprises providing at least two cores, expanding a polymeric material, extruding the expanded polymeric material around the cores, and allowing the expanded polymeric material to collapse onto the cores. In either of these situations, the present invention operates as an open loop control system. Such methods can be used for analytical, semi-preparative processes, initial clarification, preparative filtration and process scale applications.