A vehicular rear window assembly for a vehicle comprises a first fixed pane, a second fixed pane, a sliding pane, which is supported for horizontal movement between open and closed positions, and a drive assembly. The waste water purification plant has at least one plant container, a feed unit, an evacuation unit and plants. The device includes a control circuit for changing the size of the buffer transistor. The optical beamforming RF transmitter further includes a mode-locked laser having an output optically coupled to the input of the optical WDM splitter. Alternative embodiments similarly predict the possibility of head-disk crash on the basis of the maximum value of several samples of the position error signal and on the basis of the maximum value of several samples of the square of the position error signal amplitude .