A forged copper burner enclosure capable of being mounted within the side wall of a steel melting furnace for the purpose of providing an improved cooling characteristic to a burner lance. The voice communication is associated with data stored by the first electronic device. The control unit executes a synchronous control that a time rate of change of the working angle and a time rate of change of the phase are synchronized with each other in a transient state that the engine operating condition changes. In one embodiment, selecting may comprise using load-balancing, cookie-persistence, or the like.