A data processing system having a user configurable memory controller, one or more local block RAMs, one or more global block RAMs and a processor core can be configured in a single field programmable gate array. The method adapts airflow to a variable demand for flow or mechanical or electric power in a centrifugal compressor of a turbine engine. A fixed locking member is mounted within the head restraint. The interface unit converts at least some of the data intended for the subscriber line using the user-switching communications network into data of a line-switching communications network. A location of a feature within the scanned image of the document, other than the pair of fiducial marks and the code mark, is determined based on the pair of fiducial marks and the code mark within the scanned image. An active area of the pipe grate is adjusted to form at least one inactive bed area that is out of use by shutting off the supply of gaseous medium to some of the pipes of the pipe grate utilizing pipe-specific control means included in at least some of the pipes of the pipe grate.