Zhang Huan, Ding Jinliang, Feng Liang, Chen Tan Kay, Li Ke
IEEE Trans Cybern. 2024 Dec;54(12):7430-7442. doi: 10.1109/TCYB.2024.3443396. Epub 2024 Nov 27.
Dynamic environments pose great challenges for expensive optimization problems, as the objective functions of these problems change over time and thus require remarkable computational resources to track the optimal solutions. Although data-driven evolutionary optimization and Bayesian optimization (BO) approaches have shown promise in solving expensive optimization problems in static environments, the attempts to develop such approaches in dynamic environments remain rarely explored. In this article, we propose a simple yet effective meta-learning-based optimization framework for solving the expensive dynamic optimization problems. This framework is flexible, allowing any off-the-shelf continuously differentiable surrogate model to be used in a plug-in manner, either in data-driven evolutionary optimization or BO approaches. In particular, the framework consists of two unique components: 1) the meta-learning component, in which a gradient-based meta-learning approach is adopted to learn experience (effective model parameters) across different dynamics along the optimization process and 2) the adaptation component, where the learned experience (model parameters) is used as the initial parameters for fast adaptation in the dynamic environment based on few shot samples. By doing so, the optimization process is able to quickly initiate the search in a new environment within a strictly restricted computational budget. Experiments demonstrate the effectiveness of the proposed algorithm framework compared to several state-of-the-art algorithms on common benchmark test problems under different dynamic characteristics.
动态环境给昂贵的优化问题带来了巨大挑战,因为这些问题的目标函数会随时间变化,因此需要大量计算资源来追踪最优解。尽管数据驱动的进化优化和贝叶斯优化(BO)方法在解决静态环境中的昂贵优化问题方面已显示出前景,但在动态环境中开发此类方法的尝试仍很少被探索。在本文中,我们提出了一个简单而有效的基于元学习的优化框架,用于解决昂贵的动态优化问题。该框架很灵活,允许以插件方式使用任何现成的连续可微代理模型,无论是在数据驱动的进化优化还是BO方法中。特别地,该框架由两个独特的组件组成:1)元学习组件,其中采用基于梯度的元学习方法在优化过程中跨不同动态学习经验(有效的模型参数);2)适应组件,其中将学习到的经验(模型参数)用作基于少量样本在动态环境中进行快速适应的初始参数。通过这样做,优化过程能够在严格受限的计算预算内快速在新环境中启动搜索。实验表明,与几种在不同动态特性下的常见基准测试问题上的现有算法相比,所提出的算法框架是有效的。