An artificial foliage structure with wire cores embedded in its leafy parts causing these parts to \u201cspring back\u201d upon removal of compressive loading acting thereupon. Based on the electric signals, the distance from one of the locations to the source of the acoustical signal is calculated to generate a distance signal. The photoconductor unit is detached when the developer container is either displaced from an initially attached position or is removed from the main body and the exposure device displacing device has displaced the exposure device to the second position. Based on the reception operation information, the base station transmits a reception operation indication to the terminal.