Methods and apparatus for enabling inconsistent or unsafe threads to efficiently reach a consistent or safe state when a requesting thread requests a consistent state are disclosed. By using the method of the present invention substructure features may be located through an outer skin with sufficient accuracy to control assembly operations and to meet engineering tolerances. Also, the graphic controller displays, at each of positions corresponding to each of buttons, characters in both each of languages, which is selected by switching with each of buttons, and a language currently selected.