A water level sensor and a dishwasher having the same are disclosed, in which water level is sensed for stable supply of washing water. The continuous noise detection system and method may be used in conjunction with any existing three-way call detection system and method, including for example, a system and method that monitors the active communications of the telephone management system for pulses of energy indicative of a three-way call. Recesses can be formed in a transparent window in the polishing pad. Therapeutic agents delivered in accordance with the present invention have improved bioavailability, including improved systemic distribution and improved delivery to particular tissues. The controller interrupts current supply to the heat source if such a jam has occurred. The second cam section is moveably mounted to the molding machine to allow the exit portion of the second cam section to be moved relative to the entrance portion of the first cam section, to insure that the cam followers exiting the exit portion of the second cam section are properly aligned to enter the entrance portion of the first cam section.