The invention relates to a method for updating software that is stored in a computer of a data communication system, a computer to be used in a data communication system, and a data communication system comprising several computers and an administrative computer. The new color matching functions are constrained to be similar to the original color matching functions while reducing calculated perceptual error between the metameric pairs. The audio processing system, in one embodiment, prioritizes the voices based on characteristics of the voices, such as the relative listening benefit of sound localization of a particular voice. A heat-sensitive adhesive activation device is disposed substantially around the drum opposite to a drum surface along the peripheral edge of the label adhering drum. The apparatus can be used as a hydrogen storage portion of certain types of secondary batteries.