论文标题
使用机器学习探索ICF输出对设计参数的敏感性
Exploring Sensitivity of ICF Outputs to Design Parameters in Experiments Using Machine Learning
论文作者
论文摘要
在惯性限制融合(ICF)中构建可持续的燃烧平台需要了解物理过程的复杂耦合以及关键实验设计变化对内爆性能的影响。虽然仿真代码用于建模ICF内爆,不完整的物理和近似值的需求会恶化其预测能力。识别可控设计输入与可测量结果之间的关系可以帮助指导实验的未来设计和仿真代码的开发,这可能会提高用于模拟ICF内爆的计算模型的准确性。在本文中,我们利用机器学习(ML)的发展和ML特征重要性/敏感性分析的方法,以仅使用专家判断而难以处理的方式来识别复杂的关系。我们使用随机森林(RF)回归进行工作,以预测一套设计参数的产量,速度和其他实验结果,并评估预测模型中重要关系和不确定性的评估。我们表明,RF模型能够以高精度学习和预测ICF实验数据,并且我们提取了特征重要性指标,这些指标可洞悉各种ICF设计配置的不同可控设计输入的物理意义。这些结果可用于增强专家直觉和仿真结果,以最佳设计ICF实验。
Building a sustainable burn platform in inertial confinement fusion (ICF) requires an understanding of the complex coupling of physical processes and the effects that key experimental design changes have on implosion performance. While simulation codes are used to model ICF implosions, incomplete physics and the need for approximations deteriorate their predictive capability. Identification of relationships between controllable design inputs and measurable outcomes can help guide the future design of experiments and development of simulation codes, which can potentially improve the accuracy of the computational models used to simulate ICF implosions. In this paper, we leverage developments in machine learning (ML) and methods for ML feature importance/sensitivity analysis to identify complex relationships in ways that are difficult to process using expert judgment alone. We present work using random forest (RF) regression for prediction of yield, velocity, and other experimental outcomes given a suite of design parameters, along with an assessment of important relationships and uncertainties in the prediction model. We show that RF models are capable of learning and predicting on ICF experimental data with high accuracy, and we extract feature importance metrics that provide insight into the physical significance of different controllable design inputs for various ICF design configurations. These results can be used to augment expert intuition and simulation results for optimal design of future ICF experiments.