Water with contaminants is treated using an aerator which has a housing which contains a fluid inlet nozzle and a fluid discharge nozzle positioned on either side of an air inlet formed in a T-pipe. The wireless bus includes a radio frequency or light wave transceiver on each card. The hyperobject includes procedures that interprets the URL generation rule and refers to a value of an attribute included as a generation rule element and processing for acquiring each of the result of the generation of URL in a linked hyperobject. A configuration protocol is used for configuring the trunk cluster by eliminating links connected to a switch upon loss of connectivity to a switch. The signal processing system is configured to calculate at least one of a time-frequency distribution or an Auto-Regressive spectral estimation of the detection signal to provide a frequency distribution of the detection signal at a plurality of times for use in determining periods in which the subject’s eye is fixed on the target based on the first and second frequency signatures.