How can a train engineer resume operation in MATC after a stop?

In MATC (Modern Automatic Train Control) systems, after a train engineer stops the operation, the proper procedure to resume operation involves pressing the ATC Start button when indications permit. This action is designed to ensure that all safety and operational protocols have been satisfied before the train is allowed to move again. The ATC system is crucial for maintaining safe speeds and ensuring that trains operate within designated parameters, and by pressing the Start button, the engineer is effectively acknowledging that it is safe to continue.

The ATC system monitors various conditions, including signals and speeds, which helps in making informed decisions before the train resumes its journey. This step acts as a safety measure and is part of the training that engineers receive to avoid accidents.

The other choices do not align with the safe operational procedures within the MATC framework. Simply pushing the throttle forward could lead to unsafe conditions if the train is not ready to proceed. Engaging the emergency brake or releasing the parking brake are actions that would not contribute to a controlled or safe restart following a temporary stop, as those measures are typically employed under different operational contexts. Therefore, pressing the ATC Start button is the correct and safe method for an engineer to resume operation.