A method and apparatus for allocating backhaul resources to a relay in a wireless communication system, particularly a method and apparatus for processing a downlink signal at a relay in a wireless communication system are discussed. A fresh-air feed is used for feeding fresh air to the cathode input. Material that encourages the growth of metal may be formed in the trench at the bottom, while leaving the region of the trench near the top free of such material to encourage growth upwardly from the bottom. The method may further include identifying delivery information that corresponds to the software application and associating the application registration information with the delivery information. The gel packs may be surrounded by matting, foam or mesh material which is sewn into the lines of stitching, or may have integral peripheral rims sewn into the lines of stitching. Each robot requests the content management unit to provide a content to be executed by the robot, downloads the content from the content management unit via the network, and determines a content execution plan to execute the content depending on specification of the robot.