A method of retrieving candidate access router discovery information in a user terminal which is present in a many access systems. Preferably, the analyzing probe includes a minimal amount of optical elements such as lenses that are subjected to the conditions of the environment of the fluid stream to be tested. This enables the driving force output to the driveshaft from the engine and the motor to be in accordance with the torque demand. The controller inhibits the discharge operation of the remaining recording sheets even if the recording sheets have not been stacked in the another stacking unit when the adjacent stacking unit is nonusable by the other recording sheets. The computing platform may act, for example, through a wireless network or wireless communication platform, to control the digital audio players; to act as a cache of digital audio data for the digital audio players; as well as provide a gateway to the Internet to enable the digital audio players to access additional digital audio content and other information. In this way, a sensor for measuring the purge fuel vapor concentration of the fuel vapor conducted from the canister to an intake passage of the engine can be eliminated.