Briefly, in accordance with one or more embodiments, a pathloss gap between a downlink pathloss from a base station to a mobile station and an uplink pathloss from the mobile station to the base station is estimated. A rotary mover engages the protruder and moves the protruder through the hole according to rotation of the rotary mover. The ultrafine metal oxide particles may be partially oxidized such as Cu2O, Ti3O4 and the like. A level of the supply voltage signal is controlled according to the control signal.