In outline recognition, to reduce the misjudge result from calculated error of the core position, reference frame transform and second derivative of curve were adopted.

The calculated error can be in one of two partitions about the desired accuracy, a feature of the structural design for the unit, which is not apparent from a purely functional specification.

But that does not rule out the possibility that a small quantity of the gas, calculated to fall within that error margin, was diverted to test some hidden centrifuges.