A freight-loading system in a cargo hold of an aircraft is provided that offers enhanced operating safety. Methods presented in the disclosure include detecting current leakage via electrode impedance measurement, electrode capacitance measurement, and testing the electrode response to test current pulse. A pixel electrode connects to the drain electrode and is disposed in the pixel region. , can be used as the inhibitor of folate activation. The mounting member includes a slot, and the latch member has a blocking member that is received within the slot when the latch member is in its latching position, to prevent removal of the valve actuator from the valve body. The size of an extent may be changed dynamically in accordance with a corresponding state change of physical storage.