Implant having a shaft which is adapted in use to be embedded in bone tissue and which has an outer surface provided with a circumferentially-oriented roughness. The controller can drive the electric actuator of the rudder device to return the rudder to its center position when the engine is stopped by the main switch or an auxiliary stop switch. The heat exchanger is provided with at least one airflow channel generating a hot airflow. 0 mass % as methacrylate polymer of an amount such that it prevents the solder powders from being sedimented at ordinary temperature and it is decomposed or evaporated in the process of heating during the soldering, and containing stearic acid amide of not less than 5. The product tracks and dividers can be separately formed or integrated into a single component. The recording device 16 recognizes an added HDD which is in the recording-device-formatted sate and whose HDD operation status is different from the device operation status, with the HDD operation status rewritten such that it corresponds with the device operation status.