Ensemble-based large-scale simulation of dynamical systems is essential to a wide range of science and engineering problems. Conventional numerical solvers used in the simulation are significantly limited by the step size for time integration, which hampers efficiency and feasibility especially when high accuracy is desired. To overcome this limitation, we propose a data-driven corrector method that allows using large step sizes while compensating for the integration error for high accuracy. This corrector is represented in the form of a vector-valued function and is modeled by a neural network to regress the error in the phase space. Hence we name the corrector neural vector (NeurVec). We show that NeurVec can achieve the same accuracy as traditional solvers with much larger step sizes. We empirically demonstrate that NeurVec can accelerate a variety of numerical solvers significantly and overcome the stability restriction of these solvers. Our results on benchmark problems, ranging from high-dimensional problems to chaotic systems, suggest that NeurVec is capable of capturing the leading error term and maintaining the statistics of ensemble forecasts.
翻译:大规模模拟动态系统,这是一系列科学和工程问题的关键。模拟中使用的常规数字解算器由于时间整合的步数大小而受到严重的限制,这有碍效率和可行性,特别是在需要高精度的情况下。为了克服这一限制,我们提议了一种数据驱动的校正器方法,允许使用大步尺寸,同时补偿集成错误的高精确度。这个校正器以矢量值函数的形式代表,由神经网络模拟,以扭转阶段空间的错误。因此我们命名了校正器神经向量(NeurVec),我们表明NeurVec可以取得与传统的分步尺寸大得多的解析器相同的精确度。我们的经验证明,NeurVec可以大大加速各种数字解析器,克服这些解析器的稳定性限制。我们从高度问题到混乱系统的基准问题的结果表明,NeurVec能够捕捉到主要的误差期,并维持全方位预报的统计。