Kernel-Adaptive Discretization Strategies for Physics-Informed Neural Networks: A Comprehensive Framework for Optimal Solution of Fredholm Integral Equations
摘要
We present the first comprehensive benchmark revealing that discretization strategy selection in Physics-Informed Neural Networks (PINNs) profoundly impacts performance for Fredholm integral equations of the second kind. Our kernel-adaptive framework systematically compares discrete coordinate, endpoint, and midpoint methods across smooth, singular, and regularized kernels. Key findings: discrete coordinate methods achieve 35% error reduction for smooth kernels through integral structure preservation, endpoint methods deliver 40% stability improvement for singular cases via explicit singularity handling, and midpoint methods provide 25% accuracy enhancement for regularized problems through optimal quadrature properties. Comparison with classical solvers (Nyström, Galerkin, Collocation) confirms that the PINN midpoint method achieves 2.5–3.5