A produce container comprises a basket portion and a closure portion, which are hingedly secured to one another to be relatively movable between an open configuration and a closed configuration. At this time, a ring-shaped gap is provided between the rotor and the stator, and portions facing the ring-shaped gap are equally divided into the same number of parts. A controller operates the switches according to various transfer methods. An arousal level estimation unit estimates a driver’s arousal level based on a result of comparison between the initial residual set by the residual setup unit and the residual calculated by the residual calculation unit after the initialization period has elapsed.