Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:The original double gyre(1) is a 2D, deterministic, time-varying, closedform vector field dataset defined on [0, 0] × [2, 1]; and we synthetically injected uncertainties by adding independent Gaussian noises into the u and v components:
Category: