A pedal assembly comprises parking brake and service brake pedal levers. Embodiments of the present invention improve the bandwidth utilization rate while implementing the transparent transporting of the LAN signal in the OTN. The lid frame can include a plurality of supports installed apart from each other so as to surround the nuclear fuel assembly placed on the base frame, and a plurality of clamps separated from each other, coupled to the plurality of supports perpendicular to the plurality of supports, rotatably hinged to the base frame, and configured to clamp the nuclear fuel assembly.