Abstract: A method of determining the flow rate of a fluid in a conduit. Ultrasonic energy is directed through the conduit along multiple paths. The ultrasonic energy is detected and measured using a range gated Doppler technique to determine the velocity of the fluid at several points in the conduit. These point velocities are used to calculate the average flow rate of the fluid in the conduit.

Abstract: A method of determining the flow rate of a fluid in a conduit. Ultrasonic energy is directed through the conduit along multiple paths. The ultrasonic energy is detected and measured using a range gated Doppler technique to determine the velocity of the fluid at several points in the conduit. These point velocities are used to calculate the average flow rate of the fluid in the conduit.

Abstract: An ion trap mobility spectrometer calibration system and method wherein the maximum response of the spectrometer is determined. A quantity Q0 is chosen representing a response which is a predetermined percentage of the maximum response. Input to the ion trap mobility spectrometer are at least two known quantities Q1 and Q2 of an analyte, which have a predetermined relationship with Q0. The responses corresponding to R1 and R2 of the ion trap mobility spectrometer are observed based on the respective inputs of quantities Q1 and Q2. R1, R2, and Q1 and Q2 are then used to calculate the calibration constants in an equation describing a curve where the response of the ion trap mobility spectrometer is a function of the quantity of the analyte input therein. The calculated calibration constants are input to thereafter determine, from the response, the quantity of a detected analyte based on the equation.

Abstract: A flow meter is powered by a loop power supply which supplies a supply voltage. A load is powered by a load voltage and includes at least a processor for calculating a flow rate, an ultrasonic transducer power circuit, and an ultrasonic transducer receiving circuit. A power regulating circuit is disposed between the loop power supply and the load and includes a power converter responsive to the supply voltage to vary the load voltage in response to a control signal, a safe storage device between the converter and the load for storing power and for delivering power when required by the load, and a control subsystem for providing the control signal to the converter based on the setting of the loop power supply by the load. A power management detects the load voltage and to reduces the power consumption of the load at one or more predetermined set points.