Partial oxidation products andor ammoxidation products of an olefinic hydrocarbon A\u2032 are prepared by a process in which said olefinic hydrocarbon is produced during normal operation by partial dehydrogenation andor oxydehydrogenation of hydrocarbon A and fed in from another source during partial or complete nonoperation of the dehydrogenation andor oxydehydrogenation. When a new data container, such as a lun, is created, a security appliance generates a signature of the data container, by, e. A multiplexing input circuit selects and outputs one of a data input signal and a test input signal as a latch input signal in response to the first pulse signal and the second pulse signal.