摘要
粗大晶粒产生的大量散射噪声而导致的超声检测信号信噪比低问题是粗晶结构超声检测面临的一大难题。针对现有稀疏降噪方法在波形失真和幅值衰减方面的不足,本文提出了一种基于非凸变量重叠群稀疏变分的超声信号降噪方法。基于含散射噪声的典型超声信号,分析了非凸变量重叠群稀疏变分方法的主要参数(如非凸变量函数类型、正则化参数和乘法因子等)对其降噪效果的影响,并确定了适合超声信号降噪处理的参数选择依据。在此基础上,将非凸变量重叠群稀疏变分方法应用于典型钢锭超声检测信号的降噪处理。结果表明,该方法能够很好剔除钢锭超声检测信号中的散射噪声,提高了钢锭超声全聚焦成像的信噪比6 dB以上,研究工作为粗晶材料超声检测作了有益探索。
The low signal-to-noise ratio is a major challenge for ultrasonic inspection of coarse crystal structures, which is caused by the large amount of scattering noise generated by coarse grains. To overcome the insufficient of the traditional signal denoising method in waveform distortion and amplitude attenuation, an overlapping group sparse variational method based on the non-convex penalty function is proposed for ultrasonic signals denoising. Based on the typical ultrasonic signal containing scattered noise, the influence of the main parameters of the sparse variational method for overlapping groups of nonconvex variables(such as the type of function of nonconvex variables, regularization parameters and multiplication factors) on its noise suppression effectiveness is analyzed, and the basis for determination of suitable parameters in processing of ultrasonic signals is determined. On this basis, the overlapping group sparse variational method is applied to the noise suppression of ultrasonic signals detected from steel ingot. Results show that the method can effectively suppress the scattering noise in ultrasonic signals detected from steel ingot and improve the signal-to-noise ratio of ultrasonic imaging by more than 6 dB. The research work is a useful exploration for ultrasonic detection of coarse crystalline materials.
作者
张家玮
焦敬品
陈昌华
高翔
Zhang Jiawei;Jiao Jingpin;Chen Changhua;Gao Xiang(Faculy of Materials and Manufacturing Beijing Universilyof Technology Beijing 100124,China;Technology Center,Nanjing Derelop Aduanced Manufacturing Co.,Ltd.,Nanjing 210048,China)
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2022年第4期234-245,共12页
Chinese Journal of Scientific Instrument
基金
国家自然科学基金(11972053,12004018)项目资助。
关键词
超声检测
非凸变量函数
重叠群稀疏变分
散射噪声
ultrasonic testing
non-convex penalty function
overlapping group sparse variational method
scattering noise
