论文标题
通过降低基于深度学习的操作员近似的订单建模,对心脏力学的有效近似
Efficient approximation of cardiac mechanics through reduced order modeling with deep learning-based operator approximation
论文作者
论文摘要
减少高保真性所需的计算时间,用于解决心脏力学问题的全订单模型(FOM)对于允许将患者特异性模拟转化为临床实践至关重要。尽管FOM(例如基于有限元方法)提供了心脏机械功能的宝贵信息,但可能需要多达数十万个自由度来获得准确的数值结果。事实上,即使在强大的超级计算机上,也只需模拟几个心跳还是需要数小时的CPU时间。此外,心脏模型取决于一组输入参数,我们可以让这些参数变化以探索多个虚拟方案。为了大大降低计算成本来计算可靠的解决方案,我们依赖于使用新的基于深度学习的操作员近似授权的减少基础方法,我们称之为深虫网技术。我们的策略结合了一种基于投影的Pod-galerkin方法与深层神经网络,用于近似(还原)非线性操作员,克服了与标准超重还原技术相关的典型计算瓶颈。证明该方法可为心脏力学问题提供可靠的近似值,从而超过经典投影的ROM在计算速度的数量级,并增强前进不确定性量化分析,否则无法承受。
Reducing the computational time required by high-fidelity, full order models (FOMs) for the solution of problems in cardiac mechanics is crucial to allow the translation of patient-specific simulations into clinical practice. While FOMs, such as those based on the finite element method, provide valuable information of the cardiac mechanical function, up to hundreds of thousands degrees of freedom may be needed to obtain accurate numerical results. As a matter of fact, simulating even just a few heartbeats can require hours to days of CPU time even on powerful supercomputers. In addition, cardiac models depend on a set of input parameters that we could let vary in order to explore multiple virtual scenarios. To compute reliable solutions at a greatly reduced computational cost, we rely on a reduced basis method empowered with a new deep-learning based operator approximation, which we refer to as Deep-HyROMnet technique. Our strategy combines a projection-based POD-Galerkin method with deep neural networks for the approximation of (reduced) nonlinear operators, overcoming the typical computational bottleneck associated with standard hyper-reduction techniques. This method is shown to provide reliable approximations to cardiac mechanics problems outperforming classical projection-based ROMs in terms of computational speed-up of orders of magnitude, and enhancing forward uncertainty quantification analysis otherwise unaffordable.