A stator of an electric motor includes a stator core including an annular yoke. Specifically, various techniques and systems are provided for connecting a new network device to a network and limiting access of the network device while authenticating the new network device. Such a calendar structure preferably provides two slots per tier and uses a temporal pointer based on virtual time. A mounting hole is formed in the waterproof type keypad sheet material and a microphone holder is inserted into the mounting hole.