A virtual environment, including at least one virtual element representing a component of an item is generated. Essentially, the wafer is moved along one direction and an aperture mechanism having an aperture is moved along another direction, so that the projected area of an ion beam filtered by the aperture is two-dimensionally scanned over the wafer. A magnetic field is generated around the processing space by a magnetic field generating means. The inner member is configured to be positioned within the bore of the outer member. Depending on the state of a victimized cache line, an internal inquiry may be issued to other caches andor a write-back operation may be performed prior to victimizing the selected cache line.