对中子和X射线反射率数据的神经网络分析,包括先前的知识
Valentin Munteanu1, Vladimir Starostin1, Alessandro Greco1
1University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany.
Journal of applied crystallography
|April 10, 2024
概括
一种新的机器学习方法使用动态先前边界来解决多层薄膜分析中的反向问题. 这种方法克服了标准神经网络的局限性,可以从反射率数据中准确地确定参数.
科学领域:
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
- 计算科学 计算科学
背景情况:
- 从中子和X射线反射度来确定多层薄膜的物理参数是由于相位模两可的原因而造成的不确定反向问题.
- 标准神经网络在处理这些反向问题的模糊性和复杂性方面面临局限性.
- 以前的机器学习解决方案在可以考虑的参数范围和数量上受到限制.
研究的目的:
- 开发一种新的机器学习方法,准确确定多层薄膜的物理参数.
- 在反射性分析中克服未确定反向问题的基本局限性.
- 允许灵活地将先前知识纳入受约束的预测.
主要方法:
- 一种新的神经网络训练程序,包含物理参数的动态先前边界.
- 同时训练参数空间的正确位置的子间隔.
- 在推断过程中,灵活输入用户定义的先前知识.
主要成果:
- 该方法成功地确定了多层薄膜的物理参数,克服了相位模糊性.
- 在各种场景中证明了有效性,包括盒式模型和以物理为灵感的参数化.
- 随着问题的复杂性增加而有利地扩展,处理多达17个参数的模型.
结论:
- 开发的机器学习方法有效地解决了多层薄膜分析中的未确定反向问题.
- 动态先前边界增强神经网络的能力,以准确确定参数.
- 该方法为复杂的反射性数据分析提供了可扩展和灵活的解决方案.
相关概念视频
02:18X-ray Crystallography
23.9K
The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
23.9K
01:10X-ray Diffraction of Biological Samples
3.8K
X-ray diffraction or XRD is an analytical tool that utilizes X-rays to study ordered structures such as crystalline organic and inorganic samples, polycrystalline materials, proteins, carbohydrates, and drugs.
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal...
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal...
3.8K