Abstract: A brake system including: (i) hydraulic brakes provided for respective wheels of a vehicle, and configured to be activated by hydraulic pressures of respective brake cylinders so as to restrain rotations of the respective wheels; (ii) a power hydraulic pressure source including a drive source that is activatable by supply of electric energy, and configured to generate hydraulic pressure by activation of the drive source; and (iii) a common passage to which the power hydraulic pressure source and the brake cylinders of the hydraulic brakes are connected. The brake cylinders include a first brake cylinder connected to the common passage via a first individual passage that is provided with a normally-close electromagnetic valve as a first individual control valve. The brake cylinders include a second brake cylinder connected to the common passage via a second individual passage that is provided with a normally-open electromagnetic valve as a second individual control valve.

Abstract: An output characteristic of a fuel cell is estimated by detecting an output current of the fuel cell and a voltage between terminals of the fuel cell, and then estimating the output characteristic of the fuel cell on the basis of the detected output current and the detected voltage between the terminals, and a basic output characteristic of the fuel cell.

Abstract: An output characteristic of a fuel cell is estimated by detecting an output current of the fuel cell and a voltage between terminals of the fuel cell, and then estimating the output characteristic of the fuel cell on the basis of the detected output current and the detected voltage between the terminals, and a basic output characteristic of the fuel cell.

Abstract: In a torque-down control device, an entire delay amount SB of ignition timing is restricted using a guard value GSB. Also, when a rotational speed change &Dgr;NT of a turbine speed NT during delay control falls out of an allowable range, the feedback control of the entire delay amount SB is performed based on the rotational speed change &Dgr;NT is equal to a target rotational speed change &Dgr;NTT. Accordingly, an excessive decrease in engine torque even when downshifting is performed simultaneously with delay control by a knock control portion. Further, the feedback control of the entire delay amount SB is performed based on the rotational speed change &Dgr;NT, and the guard value GSB is learned and corrected based on the feedback correction amount. Accordingly, an appropriate shifting characteristic can be obtained regardless of individual differences and change with time.