公开(公告)号：US12241870B2

公开(公告)日：2025-03-04

申请号：US17776909

申请日：2022-04-04

Applicant: KOREA RESEARCH INSTITUTE OF STANDARDS AND SCIENCE

Inventor： Jong Moon Ha ,  Won Jae Choi ,  Hong Min Seung

IPC: G01N29/44 ,  G01N29/024 ,  G06N3/0455 ,  G06N3/08

Abstract: An ultrasonic NDT method and system, which can extract and analyze a defect signal even when a signal reflected from a defect interferes with a unique initial pulse of an ultrasonic transducer or a signal reflected from the surface of a test object, and an autoencoder-based prediction model training method used therefor. The method may include acquiring a measured signal by transmitting an ultrasonic wave to a test object and receiving an ultrasonic wave reflected from the test object; inputting the measured signal to an autoencoder-based prediction model and predicting a reference signal which is to be expected to be measured from a test object with no defect; calculating a residual signal as the absolute value of a difference between the measured signal and the reference signal; and analyzing information on a defect contained in the test object by analyzing the residual signal.

公开(公告)号：US12142255B2

公开(公告)日：2024-11-12

申请号：US17777465

申请日：2020-11-11

Applicant: KOREA RESEARCH INSTITUTE OF STANDARDS AND SCIENCE

Inventor： Won Jae Choi ,  Miso Kim ,  Jae Yub Hyun

IPC: G10K11/30 ,  G02B1/00 ,  G10K11/24

Abstract: A gradient-index phononic crystal flat lens which controls the behavior of an acoustic wave having a designated frequency. The gradient-index phononic crystal flat lens may include one or more super cells each having a plurality of layers stacked in a vertical direction according to a target gradient index profile, wherein each of the layers is composed of an aggregate in which unit cells having scatterers formed with the same size in the centers thereof are arranged in a horizontal direction. The one or more super cells may each include a divider provided between the neighboring layers, and configured to force the acoustic wave to propagate in the horizontal direction within the gradient-index phononic crystal flat lens.