A vibration sensor assembly having a rigid surface and a transducer integrated with the rigid surface. The transducer measures structure-borne sound waves that cause vibration motion of the rigid surface. The rigid surface may be glass, metal or plastic and may be part of an interior part or panel, or an exterior panel, of a vehicle.

An acoustic testing apparatus may include connections for multiple devices under test (DUTs) to support simultaneous testing of two or more miniature electroacoustic devices. The acoustic testing apparatus may allow the testing of multiple DUTs with a ratio of less than one reference microphone per DUT. Thus, the speed of testing DUTs may be increased without adding significant cost through additional reference microphones. For example, a single reference microphone may be used to test two or four DUTs coupled together through an acoustic test cavity.

In order to facilitate the disposition of multiple noise measuring points in a distributed manner, this underwater noise monitoring device is provide with: a processing unit in which, by using data which was acquired using optical fibers installed underwater or on a bottom of water and which indicates noise or vibration at the position of each of the optical fibers, a statistical value of the amount of noise or vibration is derived at the time and the place when/where the data was acquired; and an output unit that outputs the statistical value.

A gas sensor for detecting a gas in an environment is disclosed. The gas sensor comprises a housing having a cavity and a vent hole within the housing and a distributed element resonator within the cavity. The cavity includes a bottom surface and a top surface, and the housing is configured to receive the gas from the environment into the cavity through the vent hole. The distributed element resonator has an input terminal configured to receive a radio frequency input signal and an output terminal configured to produce an output signal.

A method for microphone selection, applied in a mobile device having at least two microphones, the method includes: transmitting, by using an ultrasonic transmitter of the mobile device, first ultrasonic waves within a testing box, wherein the first ultrasonic waves are transmitted with a predefined transmission strength and at different frequencies selected from a predefined frequency range; acquiring, by using each of the at least two microphones to receive second ultrasonic waves reflected from the first ultrasonic waves within the testing box, frequency response values of the second ultrasonic waves received by each of the at least two microphones; and determining one of the at least two microphones which has a highest frequency response value, as a microphone for receiving ultrasonic waves for the mobile device.

A system analyzes a state of an inductive operator. The system includes a measuring device that is configured to: detect an acoustic reference signal and a plurality of operating variables, which can change over time, of the inductive operator or a reference inductive operator during a reference time period; and detect an acoustic signal and the operating variables during a productive time period. The system also includes an evaluating device that is configured to: generate a reference data set from the reference signal and a productive data set from the acoustic signal; perform a regression analysis of the reference data set and thereby create a model for description of the acoustic reference signal by the operating variables; and generate a state evaluation of the inductive operator from a difference between the productive data set and values modelled in accordance with the model.

A system analyzes a state of an inductive operator. The system includes a measuring device that is configured to: detect an acoustic reference signal and a plurality of operating variables, which can change over time, of the inductive operator or a reference inductive operator during a reference time period; and detect an acoustic signal and the operating variables during a productive time period. The system also includes an evaluating device that is configured to: generate a reference data set from the reference signal and a productive data set from the acoustic signal; perform a regression analysis of the reference data set and thereby create a model for description of the acoustic reference signal by the operating variables; and generate a state evaluation of the inductive operator from a difference between the productive data set and values modelled in accordance with the model.

At least one exemplary embodiment is directed to a communication device that includes a microphone configured to detect an acoustic signal from an acoustic environment, and a processor, configured to detect an acoustical dampening between the acoustic environment and the microphone, based on a change in a characteristic of the acoustic signal and, responsive to the acoustical dampening, apply a compensation filter to the acoustic signal to form a compensated acoustic signal that is reproduced. Other embodiments are disclosed.

At least one exemplary embodiment is directed to a communication device that includes a microphone configured to detect an acoustic signal from an acoustic environment, and a processor, configured to detect an acoustical dampening between the acoustic environment and the microphone, based on a change in a characteristic of the acoustic signal and, responsive to the acoustical dampening, apply a compensation filter to the acoustic signal to form a compensated acoustic signal that is reproduced. Other embodiments are disclosed.

A piezoelectric-body film joint substrate includes a substrate, a first electrode provided on the substrate, a first piezoelectric-body film stuck on the first electrode and including a first piezoelectric film and a first upper electrode film formed on the first piezoelectric film, a second electrode provided on the substrate, and a second piezoelectric-body film stuck on the second electrode and including a second piezoelectric film different from the first piezoelectric film and a second upper electrode film formed on the second piezoelectric film, wherein a height from an upper surface of the substrate, on which the first electrode and the second electrode are formed, to a top of the first upper electrode film and a height from the upper surface of the substrate to a top of the second upper electrode film differ from each other.