A method, apparatus and system enable improved demultiplexing in a virtual machine environment. The locking doorknob is an electro-mechanical device which can be powered by a remote electrical power system, specifically by electromagnetic induction through the door latch and strike plate. A delivery device is described for guiding a cardiac lead to a desired implant location, the delivery device including a grasper mechanism for releasably holding the cardiac lead. The switching belt includes a surface where the shielding portion is disposed to face a non-paper passing region in the heating member, suspended to be rotatable between a roller and the protruding portion, and selectively arranged in one of a shielding position and a non-shielding position by rotation of the roller.