Casing shoes comprise a nose portion having an inner profile and an outer profile. Next, the method represents a systematic defect by modifying structures in the integrated circuit layout to create modified structures. The chuck can be heated to specified temperatures to achieve variable heating of a wafer, PCB, or pallet disposed thereon. The invention may be embodied in a computer implemented process andor in apparatus performing such computer implemented process. 11, which includes a management mechanism for determining link state of virtual circuits, but no mechanism for determining link state of virtual channels.