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arXiv 2605.03497cs.LG
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GRIFDIR:不规则域上的图分辨率不变扩散模型

GRIFDIR: Graph Resolution-Invariant Diffusion Models over Irregular Domains

University of Cambridge(剑桥大学);Technical University of Denmark(丹麦技术大学);Simon Fraser University(西蒙弗雷泽大学);Helmholtz Imaging(亥姆霍兹成像中心);Deutsches Elektronen-Synchrotron DESY(德国电子同步加速器研究所)

James Rowbottom, Elizabeth L. Baker, Nick Huang, Ben Adcock, Carola-Bibiane Schönlieb, Alexander Denker

AI总结:

本文提出GRIFDIR架构,将广义图卷积核表示为有限元函数,使函数空间扩散模型能直接处理不规则域上的非结构化网格,实现分辨率不变性和高保真采样。

摘要:

基于分数的无限维函数空间扩散模型为函数值数据建模提供了数学上严谨的框架,具有分辨率不变性和处理不规则离散化等关键优势。然而,实际实现一直难以完全实现这些优势。现有的骨干网络如傅里叶神经算子往往偏向于规则网格,无法泛化到复杂的域拓扑。我们提出了一种用于函数空间扩散模型的架构GRIFDIR,该架构将广义图卷积核表示为有限元函数,使得分网络能够直接在任意形状域上的非结构化网格上操作。我们通过一系列跨多种几何形状(包括非凸域和多连通域)的无条件和条件采样实验证明了我们网络架构的有效性。结果表明,所提出的方法保持了分辨率不变性,并在捕获非平凡几何上的函数分布方面实现了高保真度。

英文摘要:

Score-based diffusion models in infinite-dimensional function spaces provide a mathematically principled framework for modelling function-valued data, offering key advantages such as resolution invariance and the ability to handle irregular discretisations. However, practical implementations have struggled to fully realise these benefits. Existing backbones like Fourier neural operators are often biased towards regular grids and fail to generalise to complex domain topologies. We introduce an architecture, GRIFDIR, for function-space diffusion models that represents generalised graph convolutional kernels as finite element functions, allowing the score network to operate directly on unstructured meshes over domains of arbitrary shape. We demonstrate the efficacy of our network architecture through a series of unconditional and conditional sampling experiments across diverse geometries, including non-convex and multiply-connected domains. Our results show that the proposed method maintains resolution invariance and achieves high fidelity in capturing functional distributions on non-trivial geometries.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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