Solving the Biharmonic Equation with Coupled Physics-informed Neural Networks Based on Self-adaptive Loss Balancing

Journal: Journal of Higher Education Research DOI: 10.32629/jher.v7i1.4875

Jing Jiang

College of Mathematics and Statistics, Guangxi Normal University, Guilin 541006, China

Abstract

Standard Physics-informed neural networks (PINNs) encounter notable challenges in solving this equation numerically, such as inadequate approximation accuracy, considerable computational expense, and difficulties in loss function optimization. To mitigate these limitations, we propose introducing an auxiliary variable to decompose the fourth-order biharmonic equation into a coupled system of two second-order partial differential equations. By separately approximating the original solution and the intermediate variable, this approach effectively alleviates the numerical errors associated with computing high-order derivatives while also reducing computational overhead. Furthermore, we incorporate an adaptive loss weighting scheme to dynamically balance the contributions of the PDE various PDE loss terms during training, thereby addressing the issue of loss imbalance inherent in multi-constrained learning. The effectiveness of the proposed method is validated through several numerical experiments.

Keywords

biharmonic equation, physics-informed neural networks, loss function, self-adaptive loss weighting

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