A polishing pad for a chemical mechanical polishing apparatus. The assembly enables the fuel cell vehicle to be driven in a limp home mode in the event of an emergency by adjustment of the pressure of hydrogen. A second-key signal representative of a second key is generated from second-key base information being a base of the second key. The electrode and the integrated high-temperaturehigh-pressure chemical sensors work properly at the temperature range between 0 and 400 under the pressure up to 60 MPa and accurately measure various electrochemical parameters of liquid, displaying working stability and long lifespan. The apparatus also includes an interpreted recovery score module that creates and updates an interpreted recovery score based on the fatigue level and the dynamic recovery profile.