Δ-学习应用于粗粒度同质液体
1Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47906, USA.
The Journal of chemical physics
|August 1, 2023
概括
德尔塔学习模型通过学习与基于物理的潜力的差异来增强粗粒度分子动力学 (CGMD),优于仅基于ML的模型. 然而,由于固有的粗粒度错误,两者都难以超越基本的对式模型.
科学领域:
- 计算化学计算化学
- 材料科学 材料科学 材料科学
- 机器学习 机器学习
背景情况:
- 粗粒度分子动力学 (CGMD) 对于模拟大规模化学和材料系统至关重要.
- 目前的CGMD方法通常是定制的,缺乏像密度函数理论这样的黑子工具的可访问性.
- 机器学习 (ML) 潜力提供了一条简化CGMD模型开发的途径,但仍处于芽阶段.
研究的目的:
- 调查三角学习模型在改进CGMD模拟中的有效性.
- 在CGMD中利用基于物理和基于ML的方法的优势.
- 将三角学习模型与仅基于机器学习和基于物理的模型进行比较.
主要方法:
- 实施的三角学习模型使用ML来学习目标CGMD变量和基于物理的潜在预测之间的残余差异.
- 与ML-only和基本对对模型对比的基准delta模型.
- 基于不同CG分辨率,映射运算符和系统拓的原子性质再现的评估性能.
主要成果:
- 在各种场景中,Delta学习模型在各种场景中始终优于ML-only CGMD模型.
- 只有ML模型有时会产生质量不正确的动态,尽管减少了训练错误,但delta模型纠正了这个问题.
- 意想不到的是,无论是delta-learning还是ML-only模型,在复制原子学性质方面,它们的表现都远远超过了基本的对对模型.
结论:
- 德尔塔学习模型比ML-only CGMD方法提供了显著的,低成本的改进.
- 复制原子性质的基本限制来自于粗粒度固有的不可减少的力误差.
- 需要进一步的研究来克服粗粒度的不准确性,以便更复杂的潜能显示出明显的优势.
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