A dynamic model is stored in memory that defines torque transmitted by the lockup clutch as a function of a plurality of torque converter operating parameters. Polyethylene resin is conveyed in a downstream direction through a mixer having a feed zone, a melt-mixing zone downstream of the feed zone, and a melt-conveying zone downstream of the melt-mixing zone; contacted with nitrogen gas in the melt-conveying zone; and conveyed through a mixer discharge to form pellets. The determined identifiers for the data objects of the data source are compared to the target data model to determine mappings between the data objects of the data source and the target data model.