A first embodiment of the invention provides a system that automatically classifies documents in a collection into clusters based on the similarities between documents, that automatically classifies new documents into the right clusters, and that may change the number or parameters of clusters under various circumstances. These processes provide manufacturers of the multi-layer tamper-evident closures ability to present variable image content in ways that would be difficult to counterfeit. A continuous slit extends across the top and bottom surfaces of the sheet and enables a wet wipe to pass from the bottom surface to the top surface or from the top surface to the bottom surface. No special paths are necessary because the signals used by the cores for communicating with the packet switch are RF signals therefore they can be broadcast by the packet switch and be received by a plurality of cores.