报告题目：超声波定量化无损检测中的正反问题高效算法及应用
The efficient algorithms for forward and inverse analysis in quantitative non-destructive evaluation by ultrasonic waves
报告时间：2022/09/29 14:30-16:00 (GMT+8, Beijing Time)
报告地点：Voovmeeting (腾讯会议) ID: 972-081-299 https://voovmeeting.com/dm/Kzyyz1Fz4Jn2
报告内容：
超声波在航空航天、机械工业、土木建筑结构的无损检测和健康检测中占据重要的地位。而基于信号分析和处理的检测方法往往仅能定性地判断结构的服役状态，或指出缺陷的大致方位，若要实现缺陷形状的精确重构，则要以弹性动力学基本原理出发，从正问题和反问题两个角度阐释超声波与缺陷作用的机理。广濑教授在弹性波与无损检测领域具有扎实的理论功底和丰富的实际经验。本次报告将主要分为两个部分：其一，介绍弹性波与缺陷作用的正问题高效数值计算方法，主要包括超声导波的传播特性研究，边界单元法在散射问题的应用及最新进展等。其二，介绍基于散射波场的缺陷定量化重构及成像方法，着重推导散射波场与缺陷几何特征间的隐含数学关系，阐述利用少量波场数据实现缺陷重构的反问题解法，并探讨波动反问题算法与压缩感知及人工神经网络等新兴算法结合的可行性。
The ultrasonic wave is a very important tool for non-destructive evaluation and structural health monitoring in industrial fields such as aerospace, mechanical and civil engineering. Currently, the commonly adopted UT-NDI approaches can usually only qualitatively judge the existence and locations of hidden flaws. In order to develop a more sophisticated quantitative NDI method, the interaction of the ultrasonic wave and internal flaws should be studied in detail by elastodynamic modeling, from both forward and inverse aspects. The report contains two parts. First, for the forward part, the efficient wave propagation and scattering simulation is proposed, in which the formulation and fast modeling using (multi-pole) boundary element method in elastic wave scattering will be introduced. Second, for the inverse part, the quantitative reconstruction and imaging of flaws in structures is to be focused on. The implicit mathematical relation between geometric properties and features of flaws and far-field data of scattered wave is found and proofed, based on which, a practical algorithm for flaw reconstruction by data from limited probes is developed. The possibilities of performing quantitative NDI with new technologies such as compressed sensing and artificial intelligence will also be discussed.
报告人简介：
广濑壮一教授是国际著名的弹性波与无损检测领域的专家。他1987年在京都大学土木系获博士学位，1999年至今任东京工业大学教授。他曾任日本无损检测协会会长、日本土木协会应用力学专业委员会会长、东京大学土木工学系主任，现任日本工学会、日本计算数理工学会理事、日本熔接协会熔接检查认定委员会委员长。他的学术兴趣包括弹性波与超声波理论与数值计算、定量化无损检测、工程中的数学反问题等。
Prof. Sohichi Hirose is a famous expert in research fields of elastic wave and non-destructive evaluation. He received PhD degree in 1987 from Kyoto University, and has been Professor in Tokyo Institute of Technology since 1999. Prof. Hirose worked as Chairman of Japanese Society of Non-destructive Inspection (JSNDI), Chairman of Committee of Applied Mechanics - Japnaese Society of Civil Engineering (CAM-JSCE), as well as Dean of Dept. of Civil Engineering, Tokyo Institute of Technology, and now is the Council Member of Japan Federation of Engineering Societies (JFES) and Japanese Society for Computational Methods in Engineering (JASCOME). Prof. Hirose’s research interests include theory and numerical modeling of elastic and ultrasonic waves, quantitative non-destructive evaluation, as well as inverse problem in engineering.