The present invention discloses a method for selecting policy decision functional entity in the Resource and Admission Control System. The invention includes an outer cylinder, an inner slide, a drive rod, an angular inner rod, an elastic supporting member and first and second locating members. A first sputtering source is configured to deposit a plurality of absorber layer atoms of a first type over at least a portion of a surface of each one of the plurality of substrates. The input buffer outputs the internal signal when an output of the detection circuit indicates that the external signal is provided.