论文标题
调查贝叶斯优化用于昂贵评估的黑匣子功能:在流体动力学中应用
Investigating Bayesian optimization for expensive-to-evaluate black box functions: Application in fluid dynamics
论文作者
论文摘要
贝叶斯优化提供了一种优化昂贵评估黑匣子功能的有效方法。它已被广泛应用于许多领域的问题,包括在计算机科学中,例如在机器学习中,以优化神经网络的超参数,以及工程学,例如在流体动力学中,以优化最大程度减少阻力的控制策略。本文凭经验研究并比较了在一系列合成测试功能上共同贝叶斯优化算法的性能和鲁棒性,以提供有关针对特定问题的贝叶斯优化算法设计的一般指导。它研究了采集函数的选择,不同数量的训练样本的影响,基于蒙特卡洛的采集功能的计算以及单点和多点优化。测试功能被认为涵盖了各种各样的挑战,因此是理想的测试床,以了解贝叶斯优化对特定挑战的性能。为了说明如何使用这些发现来告知针对特定问题量身定制的贝叶斯优化设置,在计算流体动力学领域进行了两个模拟,提供了证据,证明可以在对复杂,真实问题的目标函数的少量评估中找到合适的解决方案。我们的调查结果类似地应用于其他领域,例如机器学习和物理实验,在这些领域中,客观功能评估昂贵,并且其数学表达式未知。
Bayesian optimization provides an effective method to optimize expensive-to-evaluate black box functions. It has been widely applied to problems in many fields, including notably in computer science, e.g. in machine learning to optimize hyperparameters of neural networks, and in engineering, e.g. in fluid dynamics to optimize control strategies that maximize drag reduction. This paper empirically studies and compares the performance and the robustness of common Bayesian optimization algorithms on a range of synthetic test functions to provide general guidance on the design of Bayesian optimization algorithms for specific problems. It investigates the choice of acquisition function, the effect of different numbers of training samples, the exact and Monte Carlo based calculation of acquisition functions, and both single-point and multi-point optimization. The test functions considered cover a wide selection of challenges and therefore serve as an ideal test bed to understand the performance of Bayesian optimization to specific challenges, and in general. To illustrate how these findings can be used to inform a Bayesian optimization setup tailored to a specific problem, two simulations in the area of computational fluid dynamics are optimized, giving evidence that suitable solutions can be found in a small number of evaluations of the objective function for complex, real problems. The results of our investigation can similarly be applied to other areas, such as machine learning and physical experiments, where objective functions are expensive to evaluate and their mathematical expressions are unknown.