Abstract: Sensing particular gases in a mixture uses precise modulated heating. Sensor relative responses are compared at different temperatures and compared with known relative responses to identify gases and concentrations. Heater current sensors provide feedback control and microprocessor inputs. A processor controls complex impedances and varied frequencies in the sensors. Sensor responses at varied complex impedances and at varied frequencies are compared with known responses at those impedances and frequencies to determine existence and concentration of particular gases. Heater and sensor buses are separate or combined.

Abstract: Sensing particular gases in a mixture uses precise modulated heating. Sensor relative responses are compared at different temperatures and compared with known relative responses to identify gases and concentrations. Heater current sensors provide feedback control and microprocessor inputs. A processor controls complex impedances and varied frequencies in the sensors. Sensor responses at varied complex impedances and at varied frequencies are compared with known responses at those impedances and frequencies to determine existence and concentration of particular gases. Heater and sensor buses are separate or combined.

Abstract: Sensing particular gases in a mixture uses precise modulated heating. Sensor relative responses are compared at different temperatures and compared with known relative responses to identify gases and concentrations. Heater current sensors provide feedback control and microprocessor inputs. A processor controls complex impedances and varied frequencies in the sensors. Sensor responses at varied complex impedances and at varied frequencies are compared with known responses at those impedances and frequencies to determine existence and concentration of particular gases. Heater and sensor buses are separate or combined.

Abstract: In a Coriolis mass flow gauge, the signal from each sensor is digitized and converted into digital measuring values by one or more analog/digital converters operating with a specific digital sampling frequency. Then, using a microcomputer, each digital measuring value thus obtained is multiplied, on the one hand, with the sine value of the phase angle at the point of sampling of the alternating signal or another scanning signal with the same frequency as the alternating voltage signal, but phase-shifted against that signal and, on the other hand, with the corresponding cosine value.