A stand assembly for a computing device is provided. A network system comprises one or more Perimeter Points of Presence configured to provide a virtual perimeter. The selection unit couples for control either the closed-loop control unit or the open-loop control unit with the electric motor, depending on whether the electric motor is controlled by closed-loop control in dependence on the rotary position or by open-loop control independently of the rotary position. After adding the spherical aberration for the correction of the discriminated layer, residual spherical aberration is corrected by feedback control using a residual spherical aberration signal. The gaps between the end edges of the first plating films on the outer surface of the component main body and the outer surface of the component main body are filled with the water repellent agent. The system prevents forwarding or copying of a message sent by a local user of the plurality of local users and received by a remote user of the plurality of remote users, to another party by the control platform.