For example, the operating parameter could be adjusted to achieve a desired difference between {HEAD ~ the measured anisotropy} of the first surface and {TAIL ~ the measured anisotropy} of the second surface 
For example , the operating parameter could be adjusted to achieve a desired difference between { HEAD ~ the measured anisotropy } of the first surface and { TAIL ~ the measured anisotropy } of the second surface
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH