A light-acoustic system and method for detecting an anomaly in a structure are provided. The system includes a light source configured to emit an excitation light and at least one excitation element attached to a surface of a structure. The at least one excitation element includes a photostrictive material and is configured to receive the excitation light for generating an oscillating strain. The oscillating strain generates an acoustic wave in the structure. The system also includes a detector configured to detect the acoustic wave.

A method of monitoring both liner wear and charge impact in an industrial mill uses a sensor mounted on an elongated element deployed through a shell into a liner of the mill. The elongated element wears at a same rate as the liner under conditions within the shell. Liner wear is related to a reduction in length of the elongated element as measured by travel time of an ultrasound wave, while location and strength of charge impact is related to change in amplitude of vibrations caused by the charge impact. Liner wear measurement can be improved by using shear ultrasound waves instead of conventional longitudinal ultrasound waves. A mill monitoring apparatus has a means for acquiring ultrasonic waves and audible sound waves using the same digitizer; a means for determining the angular position of the monitoring apparatus; and a means for supplying electric power to the apparatus.

An object of the invention is to provide an ultrasonic probe, an ultrasonic diagnostic device, and a manufacturing method of the ultrasonic probe, which are capable of reducing a product defect rate. An ultrasonic probe according to one embodiment includes a plurality of channels. Each of the plurality of channels includes a vibrator that outputs an ultrasonic wave, and a transmission circuit unit that changes an output in response to an input transmission signal and causes the vibrator to output the ultrasonic wave by driving the vibrator with the output. Here, the transmission circuit unit includes a stop signal holding circuit that holds a stop signal when the stop signal is input in advance, and selects whether to change the output in response to the transmission signal based on whether the stop signal is held.

An object of the invention is to provide an ultrasonic probe, an ultrasonic diagnostic device, and a manufacturing method of the ultrasonic probe, which are capable of reducing a product defect rate. An ultrasonic probe according to one embodiment includes a plurality of channels. Each of the plurality of channels includes a vibrator that outputs an ultrasonic wave, and a transmission circuit unit that changes an output in response to an input transmission signal and causes the vibrator to output the ultrasonic wave by driving the vibrator with the output. Here, the transmission circuit unit includes a stop signal holding circuit that holds a stop signal when the stop signal is input in advance, and selects whether to change the output in response to the transmission signal based on whether the stop signal is held.

Described are an apparatus, computer program product, and associated methods for shaped waveform acoustic interrogation of substances and materials to determine one or more properties of the materials or substances. In some embodiments, a shaped waveform is formed by summing two or more different waveforms and an acoustic wave is generated according to the shaped waveform. The acoustic wave is transmitted by one or more transmitting transducers through the substance or material and received by one or more receiving transducers. The shaped waveform acoustic wave can have a duration or a period that is less than about 20 μs and can comprise predetermined frequency content. Characteristics of the shaped waveform acoustic wave, as received at the receiving transducer(s), including characteristics such as amplitude, frequency, time of flight, etc., can be associated with said one or more properties of the substance or material to provide for real-time monitoring of these properties.

The present disclosure proposes a non-baseline on-line stress monitoring system and monitoring method based on multi-mode Lamb wave data fusion. A Lamb wave dispersion curve is established according to geometric dimensions and material parameters of a measured object, a cut-off frequency of a first-order Lamb wave mode is obtained, an excitation frequency of a Lamb wave signal is determined, and then pure Lamb waves in S0 and A0 modes obtained inside the measured object are obtained; an acoustoelastic equation is established, an elastodynamic equation of the measured object under a prestress condition is solved, and linear relationships between a group velocity and a stress of the Lamb waves in the S0 and A0 modes under the excitation frequency are obtained; data is processed through the on-line monitoring system; a stress gradient in a depth direction is calculated, and finally, a stress state of the measured object is represented. The present disclosure does not require data under a zero stress state as baseline data, does not require designing a wedge block capable of generating a critical refraction longitudinal wave, and combines acoustoelastic effects of Lamb waves in different modes to realize online stress monitoring without the baseline data.

The present disclosure proposes a non-baseline on-line stress monitoring system and monitoring method based on multi-mode Lamb wave data fusion. A Lamb wave dispersion curve is established according to geometric dimensions and material parameters of a measured object, a cut-off frequency of a first-order Lamb wave mode is obtained, an excitation frequency of a Lamb wave signal is determined, and then pure Lamb waves in S0 and A0 modes obtained inside the measured object are obtained; an acoustoelastic equation is established, an elastodynamic equation of the measured object under a prestress condition is solved, and linear relationships between a group velocity and a stress of the Lamb waves in the S0 and A0 modes under the excitation frequency are obtained; data is processed through the on-line monitoring system; a stress gradient in a depth direction is calculated, and finally, a stress state of the measured object is represented. The present disclosure does not require data under a zero stress state as baseline data, does not require designing a wedge block capable of generating a critical refraction longitudinal wave, and combines acoustoelastic effects of Lamb waves in different modes to realize online stress monitoring without the baseline data.

Object analysis comprising measuring a frequency-dependent natural oscillation behavior of the object by dynamically-mechanically exciting the object in a defined frequency range (f) by means of generating a body oscillation by applying a test signal, and detecting a body oscillation generated in the object on account of the exciting. Moreover, the method involves simulating a frequency-dependent natural oscillation behavior for the object by generating a virtual digital representation of the object, and carrying out a finite element analysis on the basis of the virtual representation comprising dynamically exciting, in a simulated manner, the virtual representation into a virtual frequency range for generating a virtual body oscillation, calculating the virtual body oscillation generated in the object on account of the exciting in a simulated manner, and deriving an object state on the basis of a comparison of the measured natural oscillation behavior and the simulated frequency-dependent natural oscillation behavior.

A system for detecting characteristics of a fluid includes a sonic sensor. The sonic sensor includes a transducer, a transduction surface, and an acoustically reflective pad member. The transducer may be contained within a probe body, and the transduction surface may be an element of the probe body. A stem may connect the pad member to the transduction surface. The transducer will generate pulses that are transmitted to the pad member via a fluid when the transduction surface and pad member are immersed in the fluid. The system will detect the pulses when reflected and use that data to determine a speed of sound within the fluid. The system may use the speed of sound to determine density, specific gravity and/or stiffness of the fluid. The system may use that determination to assess a level of processing activity of the fluid, such as fermentation activity.

The present invention relates to an ultrasonic testing apparatus with a variable frequency, which can automatically change the frequency according to thickness and thereby detect internal defects in objects having various thicknesses. The ultrasonic testing apparatus may comprise: a nozzle jetting a medium toward an object so as to form a medium column; and a plurality of probes disposed in the nozzle so as to generate ultrasonic waves.