A method determines a measured quantity relating to the flow of a fluid through a measuring tube, in two propagation directions, and a receive signal is captured. A transit time difference is determined depending on the position of the main maximum of a cross-correlation of the receive signals. Whereupon the measured quantity is determined depending on the transit time difference, and the transmitting ultrasonic transducer is controlled in each case with an excitation signal. The excitation signal has a fixed carrier frequency. The excitation signal has a phase shift and/or an envelope with a plurality of temporally spaced maxima, and/or, if a trigger condition is fulfilled, the fulfilment of which depends on the height of the main maximum and/or of at least one secondary maximum of the cross-correlation. The determination of the measured quantity is modified compared with a normal operating mode and/or a message is output.

This fluid evaluation device is provided with an irradiation unit for irradiating a fluid with light, a light reception unit for receiving scattered light from the fluid and outputting a light reception signal, and an estimation unit for estimating at least one from among flow rate and density by mapping input points, which are on a first plane defined by flow rate and frequency and are expressed by light amount information indicating the amount of scattered light included in the light reception signal and frequency information indicating a frequency for a beat signal resulting from the Doppler shifting of the light included in the light reception signal, onto a second plane defined by fluid flow rate and fluid density.

A monitoring system for monitoring milk flow during breast feeding or milk expression uses a flow sensor arrangement to monitor milk flow levels from different regions of the breast. A map of milk flow levels for different regions of the breast is then generated and displayed.

A monitoring system for monitoring milk flow during breast feeding or milk expression uses a flow sensor arrangement to monitor milk flow levels from different regions of the breast. A map of milk flow levels for different regions of the breast is then generated and displayed.

Systems and methods are provided for estimating the flow velocity of a multi-phase flow in a pipe using injected microbubbles in combination with ultrasonic signals produced by transducers external to the pipe. The transducers can be located so that one transducer/receiver pair is downstream from a second pair by a separation distance. The receivers can preferably be located in alignment with the transducers for receiving a desirable amount of signal emitted from microbubbles that are excited by absorption of energy from a signal generated by a transducer. The frequency of the signal emitted by the microbubbles can correspond to a harmonic and/or sub-harmonic of the frequency of the signal generated by the transducer. In order to improve the signal-to-noise ratio, frequencies corresponding to a primary frequency emitted by a transducer can be filtered out.

Systems and methods are provided for estimating the flow velocity of a multi-phase flow in a pipe using injected microbubbles in combination with ultrasonic signals produced by transducers external to the pipe. The transducers can be located so that one transducer/receiver pair is downstream from a second pair by a separation distance. The receivers can preferably be located in alignment with the transducers for receiving a desirable amount of signal emitted from microbubbles that are excited by absorption of energy from a signal generated by a transducer. The frequency of the signal emitted by the microbubbles can correspond to a harmonic and/or sub-harmonic of the frequency of the signal generated by the transducer. In order to improve the signal-to-noise ratio, frequencies corresponding to a primary frequency emitted by a transducer can be filtered out.

A measurement device includes a light emitter, a light receiver, an extractor, and a processor. The light emitter illuminates an illumination target having an internal space through which a fluid flows. The light receiver receives coherent light including light scattered by the illumination target and outputs a signal corresponding to intensity of the coherent light. The extractor extracts a direct-current component from the signal output from the light receiver at a temporal change in strength of the signal. The processor calculates a calculation value for a flow state of the fluid by performing a process on the signal output from the light receiver. The process includes correction using a value of signal strength of the direct-current component and calculation of a frequency spectrum for the signal at the temporal change in the signal strength.

The present invention provides devices and systems for detecting shunt malfunction. The detection devices employ ultrasound instrumentations to evaluate shunt malfunction. The detection devices can be coupled with pumps to provide consistent shunt valve and/or reservoir actuation for reliable readings. The devices can output a determination of a degree of shunt blockage and relative location of shunt blockage.

The present invention provides devices and systems for detecting shunt malfunction. The detection devices employ ultrasound instrumentations to evaluate shunt malfunction. The detection devices can be coupled with pumps to provide consistent shunt valve and/or reservoir actuation for reliable readings. The devices can output a determination of a degree of shunt blockage and relative location of shunt blockage.

A system for observing a flow characteristic of a fluid is provided. The system includes a nadir-facing sensor, an angle flow sensor, and processing circuitry. The nadir-facing sensor and the angle flow sensor are both provided at a distance above the fluid. The nadir-facing sensor and the angle flow sensor are both radar sensors. The processing circuitry is configured to receive sensor data from the nadir-facing sensor and the angle flow sensor. The sensor data includes at least one of a fluid speed or a fluid surface level. The processing circuitry is configured to determine the flow characteristic based upon the sensor data.