An external calibrating device (10) for a measurement device, which may be an acoustic camera. The calibrating device (10) includes a sound source (11) and a light source (12), which are preferably pointed to the same direction. This direction can be a horizontal direction, where the sources (11, 12) locate on the same vertical side surface of the calibrating device (10). An IR LED can be used as the light source (12). The measurement device may instruct a user how to place and align the measurement device during the calibration process. Guidance is given by instructions, volume range information, and focusing lines on the screen. When the instructions are fulfilled, the user may acknowledge the finished calibration process.

An audio processing device includes: a sound level measuring circuit arranged to operably generate multiple sound level values, wherein the multiple sound level values respectively correspond to the sound levels generated by an audio playback device at multiple time points or the sound levels received by a microphone at multiple time points; an audio dose calculating circuit coupled with the sound level measuring circuit and arranged to operably generate an audio dose value corresponding to a measuring period based on the multiple sound level values and contents of a weighting table; a control circuit coupled with the audio dose calculating circuit and arranged to operably compare the audio dose value with a dose threshold to determine whether to generate a control signal or not; and an indication signal generating circuit coupled with the control circuit and arranged to operably generate a corresponding indication signal according to the control signal.

There is provided A method for producing an electrical impedance tomographic image of an acoustic field within a fluid, comprising the steps of: a) positioning a plurality of electrodes within a fluid; b) applying an electrical signal to each electrode within a first subset of electrodes, wherein the electrical signal applied to each electrode has a different carrier frequency and/or phase; c) measuring the electrical potential at each electrode within a second subset of electrodes; and d) processing the measured data to provide an acoustic map of the acoustic field at the required acoustic frequencies. There is also provided a system for producing an electrical impedance tomographic image of an acoustic field within a fluid using the method of any preceding claim, comprising a plurality of electrodes, a signal generator adapted to perform step (b), a device adapted to perform step (c), and a processor adapted to perform step (d).

Aspects of the disclosure include systems, methods, and program products for evaluating the condition of a component using an acoustic sensor embedded within a lighting device. A system according to the present disclosure can include a first lighting device configured to illuminate an area of an industrial plant; a first acoustic sensor embedded within the first lighting device and configured to detect an acoustic signature of a component in the industrial plant; a computing device communicatively connected to the first acoustic sensor and configured to evaluate a condition of the component in the industrial plant based on the acoustic signature.

Disclosed is a hydrocyclone monitoring system. The hydrocyclone monitoring system comprises a hydrocyclone comprising a separation chamber having an inlet for feeding an input mixture into the separation chamber and first and second outlets for ejecting flows of 5 respective first and second components of the mixture from the separation chamber. The hydrocyclone monitoring system further comprises a conduit and a sensor assembly. The conduit is connected to the first outlet and defines a channel for conducting the flow of the first component ejected from the separation chamber. The sensor assembly is configured to detect characteristics of the flow of the first component in the channel. The hydrocyclone 10 monitoring system further comprises a processing system configured to receive from the sensor assembly measurement data indicative of the characteristics of the flow of the first component, and to determine a mode of operation of the hydrocyclone based on the measurement data. Also disclosed is a method of monitoring a hydrocyclone.

Disclosed is a hydrocyclone monitoring system. The hydrocyclone monitoring system comprises a hydrocyclone comprising a separation chamber having an inlet for feeding an input mixture into the separation chamber and first and second outlets for ejecting flows of 5 respective first and second components of the mixture from the separation chamber. The hydrocyclone monitoring system further comprises a conduit and a sensor assembly. The conduit is connected to the first outlet and defines a channel for conducting the flow of the first component ejected from the separation chamber. The sensor assembly is configured to detect characteristics of the flow of the first component in the channel. The hydrocyclone 10 monitoring system further comprises a processing system configured to receive from the sensor assembly measurement data indicative of the characteristics of the flow of the first component, and to determine a mode of operation of the hydrocyclone based on the measurement data. Also disclosed is a method of monitoring a hydrocyclone.

The present disclosure relates to systems and methods of applying vibration stimuli to a plant. In some implementations, an actuator generates a vibration. The vibration may be transmitted to a vibration transmitter and from the vibration transmitter to the plant. In some implementations, the vibration may be based on recorded biometric information such as a heartbeat, pulse, nerve impulses, or the like.

A system and method may detect one or more shooting sounds and provide guidance to one or more evacuating people when an active shooting event has occurred indoors, thereby minimizing a secondary damage. The system comprises: a plurality of stations configured to detect one or more shooting sounds and transmit detection of the one or more shooting sounds; and a response server configured to receive the detection of one or more shooting sounds over a communication network, to generate action commands, respectively corresponding to each of the stations, based on the detection of the one or more shooting sounds, and to transmit the respective action commands to the each of the corresponding stations over the communication network.

A computer implemented method for determining an airborne and/or aerosol pathogen risk exposure includes determining an acoustical parameter for a portion of a building, recording, using a microphone in a mobile electronic device located in the portion of the building, sound pressure level over time originating from speech in the portion of the building, and determining the airborne and/or aerosol pathogens risk exposure as a function of the recorded sound pressure over time and the determined acoustical parameter.

A Transducer in a downhole environment with an increased amplitude of the transducer output at lower frequencies. A transducer may include a bender bar, wherein the bender bar may include a first piezoelectric layer disposed on one surface of the bender bar, a second piezoelectric layer disposed on the opposite surface of the bender bar, and a metallic substrate disposed between the first piezoelectric layer and the second piezoelectric layer. The transducer may further include a first fixed end is attached to the bender bar and connects the bender bar to a base, a second fixed end opposite the first fixed end that attaches the bender bar to the base, and a compartment disposed within the base.