A fingerprint verification method includes extracting ND sample feature points from a fingerprint image that has been sampled, assigning sample numerical values to each of the sample feature points as sample numerical value information. In one embodiment, the optical properties of tissue are determined using measured light attenuations at a set of wavelengths. The first node enables data received by the first port from the second node to be transmitted by the second port to the third node. The container forming layer is plasma etched through the masking layer openings. The centrifuge is controlled responsive to the inferred position of the phase interface.