Optimal Transducer Arrangement for Temperature Distribution Measurement in Arbitrary Convex-Shaped Space by Acoustic Computerized Tomography

Self Cite

Measurementthe act of measuring physical properties that we performhas the potential to contribute to the successful advancement of sciences and society. To open doors in physics and other sciences, various measurement methods and related applications have been developed, and ultrasound has remained a useful probe, power source, and interesting measurement object for the past two centuries. In this paper, we first summarize the basic principles of ultrasound from the viewpoint of measurement techniques for readers who just have started studying or are interested in the field of ultrasonic electronics. Moreover, we also introduce recent studiesultrasonic properties of materials, measurement techniques, piezoelectric devices, nonlinear acoustics, biomedical ultrasound, and ocean acousticsand their trends related to measurement techniques in ultrasonic electronics to provide some ideas for related applications.

Section: Transmittermentioning

confidence: 99%

Introduction of measurement techniques in ultrasonic electronics: Basic principles and recent trends

Mizutani¹,

Wakatsuki²,

Ebihara³

2016

Self Cite

“…Hence, most of the previous studies were mainly intended for a small-scale medium. [12][13][14][15][16][17][18][19] Large-scale application of the technique has been limited to the ocean. [20][21][22] To solve the problems, an acoustic travel-time tomography system for the monitoring of the vortex wind flow velocity profile has been developed, where multichannel parallel acoustic transmitter/receiver pairs are placed along opposite sides of the monitoring region.…”

Section: Introductionmentioning

confidence: 99%

Real-time monitoring system of vortex wind field using coded acoustic wave signals between parallel array elements

Terada

Yamada

2014

An acoustic travel-time tomography system for the monitoring of the vortex wind flow velocity profile has been studied, where multichannel parallel acoustic transmitter/receiver pairs are placed along opposite sides of the monitoring region. For real-time high-speed collection and computation of data, a simultaneous transmission technique of using a pseudo-noise code-modulation signal was adopted, as well as a graphics processing unit with the use of an 8-channel indoor test system, bidirectional travel time lag data along 34 propagation paths were processed in parallel. By this means, vortex wind fields, including their 2D center position, were successfully monitored at a frame rate of approximately 1 s. Real-time tracking capability for a moving vortex wind field was examined. The results showed the feasibility of the method for the monitoring of outdoor moving vortex wind fields.

“…16) Therefore, the sound velocity on the path seems to be decreased. The inside of the billet is visualized as a sound velocity distribution by ultrasonic CT, 17,18) in which the TOF variations are used as the projection data. The sound velocity distribution is not the actual sound velocity.…”

Section: Introductionmentioning

confidence: 99%

Speeding Up of Nondestructive Inspection for Shape-Distorted Billet by Simultaneous Measurement of Time of Flight

Norose

Mizutani

Wakatsuki

2013

Self Cite

We have proposed a nondestructive inspection method for steel billets using ultrasonic computerized tomography by time of flight (TOF). It has been found that the proposed method may detect defects inside high-attenuation materials with the aid of sequential pulse transmission all around the surface. However, it takes a long time to measure the TOF by this method owing to large numbers of scans and transmissions. In this paper, we propose a TOF measurement method to apply our inspection method to simultaneous TOF measurement in a shape-distorted billet to speed up the inspection. In this method, besides a measurement plane and a reference plane, a standard reference plane is used to compensate not only the effect of the characteristics between a transmitter and a receiver but also the effect of the shape distortion in simultaneous measurement. In this paper, the performance of the present method was verified by numerical simulation and experiment. As a result, the defects in a shape-distorted billet were successfully visualized in simultaneous TOF measurement by the present method. Moreover, it was confirmed that the proposed method diminished the artifacts in the computerized tomography (CT) images by compensating the error caused by multiple simultaneous transmissions. It was revealed that the present method is more robust to noise than the previous method. Therefore, it is expected that the TOF measurement in the nondestructive inspection of a shape-distorted billet can be sped up by the proposed method.