A credential management system which obviates the need to design, produce and distribute one-time printed passes to individuals authorized to be present at an event such, for example, as cast members, stage crew, security details and staff, important guests, performers, players, officials and many others. In one embodiment, a scheduler accesses an activity scheduling graph. The ceramic composite having a fracture toughness of greater than about 4. Four reference voltages are generated from the peak detector. A synthesis circuit synthesizes the corresponding set of the information items read out by the readout circuit. Other methods and systems are also provided.