A technique enables application data stored on storage devices of a storage system to be accessible by a client as either a file or logical unit number. The reception quality of a signal transmitted from another mobile station or base station is compared with a predetermined control target value such as a signal-to-interference ratio. The handles can be gripped by a user to move the rack from one location to another when the rack-coupling portion is coupled to the rack. The determined battery condition is transmitted remotely from the battery location either wirelessly or through a network to controller andor is visibly displayed at the battery location.