A centrifugal compressor has a housing assembly and an impeller rotatably connected to the housing assembly. The external connection terminal is connected to a control unit which controls the image forming unit. When it is determined by the controller that a vehicle operator is drowsy, controller initiates communication device to communicate a communication signal to service center. While the control device controls the RF unit to apply predetermined RF power to the electrode for generating plasma, the control device controls the gas supply system to supply a process gas to the process chamber alternately at a first flowrate and at a second flowrate greater than the first flowrate. Credit associated with an account of a merchant credit service may be redeemed by providing an account number of the service. The module comprises an image capture device unit for focusing an image of a subject, a LED unit for emitting light to the subject, a FPC electrically connected between the image capture device unit and the LED unit, and a connector unit for applying an electric signal to the image capture device unit.