Embodiments of the present invention set forth a method and system for reducing uncertainty in receive and transmit timestamps created by an NTP server. The thickness of the electrode is set so that the acoustic velocity of the SH boundary acoustic waves is less than the acoustic velocities of slow transverse waves propagating in the dielectric body and slow transverse waves propagating in the piezoelectric body. A preferred equivalent content reference associated with the consumer environment is selected from the initial content reference and the equivalent content references. A mean number of predefined deviations in the vertical direction of the fa\xe7ade of the building may be determined, and the number of floors of the building based on the determined mean number of predefined deviations can be then be deduced. An inlet channel supplies hydraulic medium to the closing chamber to hold the valve slide in the closed position.