sentences:  With its introduction a platform may be served in one-man operation either by ZAT-oU or the ZAT-FM, being the old "" ZAT-oU (train dispatching by train driver without technical support) or the new "" ZAT-FM (train dispatching by train driver with driver cab monitor).Officials pointed out that the one-man operation does even lower the time a train halts on a station - on the busy central lines the train on one side of the platform did often have to wait for the train in the opposite direction on the other side of the platform to be dispatched.Although most of the central lines will be converted to ZAT-FM there will be about 20 stations left in the network that will continue to have platform dispatchers.