arXiv:2412.16200cs.CVcond-mat.mtrl-sci2024-12

用3D卷积变分自编码器,自动检测电子能损谱图像中的微弱异常

Robust Spectral Anomaly Detection in EELS Spectral Images via Three Dimensional Convolutional Variational Autoencoders

  • 利用三维数据结构建模空间与光谱关联,学习纯净材料的特征
  • 在模拟缺陷下实现清晰的正常/异常光谱分离,对不同缺陷幅度均有效
  • 适合复杂材料分析,尤其在噪声强区域仍保持高重建质量

我们提出一种三维卷积变分自编码器(3D-CVAE),用于电子能量损失谱成像(EELS-SI)数据的自动异常检测。该方法充分利用EELS-SI数据立方体的三维结构,捕捉空间与光谱间的相关性,通过负对数似然损失在体相光谱上训练,学习无缺陷材料的典型特征。在对比3D-CVAE与主成分分析(PCA)的异常检测性能时,采用铁L边峰位偏移模拟材料缺陷。结果表明,3D-CVAE在各类偏移幅度下均表现更优,能实现明显的双峰分离,支持可靠分类。进一步分析显示,低维表示对数据中的异常具有鲁棒性。尽管在异常浓度降低时相较PCA的优势减弱,但本方法在噪声主导区域仍保持高重建质量。该方法为复杂材料系统中无监督的谱异常检测提供了稳健框架。

原文摘要 · Abstract (English)

We introduce a Three-Dimensional Convolutional Variational Autoencoder (3D-CVAE) for automated anomaly detection in Electron Energy Loss Spectroscopy Spectrum Imaging (EELS-SI) data. Our approach leverages the full three-dimensional structure of EELS-SI data to detect subtle spectral anomalies while preserving both spatial and spectral correlations across the datacube. By employing negative log-likelihood loss and training on bulk spectra, the model learns to reconstruct bulk features characteristic of the defect-free material. In exploring methods for anomaly detection, we evaluated both our 3D-CVAE approach and Principal Component Analysis (PCA), testing their performance using Fe L-edge peak shifts designed to simulate material defects. Our results show that 3D-CVAE achieves superior anomaly detection and maintains consistent performance across various shift magnitudes. The method demonstrates clear bimodal separation between normal and anomalous spectra, enabling reliable classification. Further analysis verifies that lower dimensional representations are robust to anomalies in the data. While performance advantages over PCA diminish with decreasing anomaly concentration, our method maintains high reconstruction quality even in challenging, noise-dominated spectral regions. This approach provides a robust framework for unsupervised automated detection of spectral anomalies in EELS-SI data, particularly valuable for analyzing complex material systems.

异常检测电子能损谱三维卷积自编码器

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。