A measurement apparatus comprises a memory that stores instructions. The measurement apparatus comprises a processor that executes the instructions stored in the memory to: identify a propagation distance which is a length of a propagation path that a sound wave transmitted from a transmitting apparatus takes before reaching a receiving apparatus; determine, based on the identified propagation distance, a method to be used to identify a propagation time for the sound wave transmitted from the transmitting apparatus to reach the receiving apparatus from among a plurality of methods for identifying a propagation time of a sound wave; identify the propagation time for the sound wave transmitted from the transmitting apparatus to reach the receiving apparatus by the determined method; and measure an air characteristic of a location on the propagation path based on the identified propagation time and the identified propagation distance.

A gas analyzer uses continuous sonic signals through a conduit to determine the composition of a gas in the conduit. A transmitting transducer drives sonic signals at a fixed frequency and a second transducer receives the sonic signals. The phase shift between two signals corresponds to the speed of sound through the gas and is related to the composition of the gas. The electronic versions of these signals are processed by lowering, or dividing, the fixed frequency which expands the range of phase shift measurement and allows the determination of an expanded range for the gas composition. In an ozone generation system, the gas analyzer is highly suitable for determining the composition of gases derived from air as a gas of known composition and a calibration point.

A method for classifying a glass object via acoustic analysis by a classifying apparatus is provided. The method including: receiving, by a processor, sound data of a knock sound generated by applying a knocking operation on the glass object; determining, by the processor, a type of the glass object by performing a knock-sound analysis to the sound data, wherein the type of the glass object includes an organic glass and an inorganic glass; if the type of the glass object is determined as the inorganic glass, receiving, by the processor, echo data of an echo induced by applying an ultrasonic-echo operation on the glass object; and determining, by the processor, a further type of the glass object by performing an echo-decay analysis to the echo data, wherein the further type of the glass object includes a crystal glass, a borosilicate glass and a soda-lime glass.

A liquid immersion sensor for a mobile device with at least two acoustic transducers is described. The liquid immersion sensor may include a signal generator having a signal generator output configured to generate a signal for transmission via a first acoustic transducer, and a signal receiver having a signal receiver input configured to receive a delayed version of the generated signal via a second acoustic transducer. The signal receiver includes a signal receiver output. The liquid immersion sensor includes a controller having a first controller input for receiving a reference signal and a second controller input coupled to the signal receiver output. The controller determines a time lag value between the reference signal and the delayed signal and generates a control output signal dependent on the phase difference. The control output signal indicates if the mobile device is immersed in liquid.

The disclosure discloses a stress gradient high-efficiency non-destructive detection system based on frequency domain calculation of broadband swept frequency signals, and a detection method thereof. The detection method includes: step 1: calibrating an LCR wave velocity of an object to be measured; step 2: calculating a starting frequency and a cut-off frequency of broadband swept frequency signals based on the LCR wave velocity of the object to be measured in the step 1 and a stress gradient measuring range in a depth direction of the object to be measured; step 3: converting phase delay to time delay information based on the phase delay of the starting frequency and the cut-off frequency in the step 2; and step 4: determining stresses of depths corresponding to different frequency components based on the time delay information in the step 3 to finally realize layer-by-layer scanning of stresses at different depths of the measured object. The disclosure is used to solve the problem of low stress gradient measuring accuracy, and realize the high-efficiency characterization of the stress gradient in the depth direction.

An acoustic inspection device and an associated method for inspecting a component are provided. The acoustic inspection device is portable and includes an acoustic transmitter and receiver that may be placed on opposite sides of an inspection region on the surface of the component. The acoustic transmitter has an array of acoustic transducers for generating an acoustic wave that travels along a surface of the component and the acoustic receiver has an array of acoustic transducers for receiving that acoustic wave. A controller determines at least one surface characteristic of the component from the measured acoustic wave, such as its crystalline structure or grain size.

Methods of detecting pipeline weakening are described herein. The methods include creating a pressure wave in a fluid flowing in a pipeline using an input transducer located at a first position along the pipeline; measuring the pressure wave using an output transducer positioned at a second position along the pipeline that is spaced from the first position, and generating an output signal based on the pressure wave; analyzing the output signal to determine a stiffness of a sidewall of the pipeline positioned between the input transducer and output transducer; and determining if the sidewall includes a defect based on the stiffness of the sidewall, including analyzing a frequency response of the output signal to detect the defect.

A device for inspecting a pipe, includes a scraper carriage, substantially cylindrical about an axis coinciding with an axis of the pipe and which is inserted into the pipe and propelled by a liquid transported by the pipe, and a measurer carried by the carriage. The measurer includes a first crown, carrying a first set of ultrasound transducers, arranged on a first circle centered on the axis and of diameter substantially equal to an inside diameter of the pipe, alternating a transmitting ultrasound transducer and a receiving ultrasound transducer, arranged so that a wave transmitted by a transmitting ultrasound transducer is reflected, by a wall of the pipe facing it, towards a counterpart receiving ultrasound transducer.

The embodiments disclosed herein relate to the examination of gemstones including diamonds, both cut/polished and rough, using the technology of Resonant Ultrasound Spectroscopy. The resonant frequencies are obtained by mechanically causing the stone to vibrate using a swept sine oscillator, sensing the resonance vibrations, and displaying the spectrum to yield a pattern describing the stone. The resonance fingerprints can be used to both track an individual stone to verify its integrity or to grade a rough stone to establish potential value.

There is provided a method for determining material properties in an active acoustic spectroscopy system, the method comprising: acquiring a multidimensional acoustic spectrum from a material in a container using acoustic spectroscopy; reducing the dimensionality of the acoustic spectrum using a mathematical dimensionality reduction method, thereby forming a reduced acoustic spectrum describing a material state; and determining if the material state belongs to a predetermined material state cluster. There is also provided a system for performing the described method.