BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250712T122019EDT-99256tpaVf@132.216.98.100 DTSTAMP:20250712T162019Z DESCRIPTION:Title:\n\nCompressive Fourier collocation methods for high-dime nsional diffusion equations with periodic boundary conditions\n\nAbstract: \n\nHigh-dimensional Partial Differential Equations (PDEs) are a popular mathematical modelling tool. However\, standard numerical techniques for s olving High-dimensional PDEs are typically affected by the curse of dimens ionality. In this work\, we tackle this challenge while focusing on statio nary diffusion equations defined over a high-dimensional domain with perio dic boundary conditions. Inspired by recent progress in high-dimensional s parse function approximation\, we propose a new method called compressive Fourier collocation. Combining ideas from compressive sensing and spectral collocation\, our method uses Monte Carlo sampling and employs sparse rec overy techniques\, such as orthogonal matching pursuit and L1 minimization \, to approximate the Fourier coefficients on given index sets of the PDE solution. We conduct a rigorous theoretical analysis showing that the appr oximation error of the proposed method is comparable with the best s-term approximation (with respect to the Fourier basis) to the solution and miti gates the curse of dimensionality with respect to the number of collocatio n points under sufficient conditions on the regularity of the diffusion co efficient. We present numerical experiments that illustrate the accuracy a nd stability of the method for the approximation of sparse and compressibl e solutions. In our current work\, noticing that a bottleneck towards impr oving the solution accuracy is the choice of the index set\, we develop a method using orthogonal matching pursuit to select the elements of the ind ex set adaptively. In addition\, we seek an efficient neural network model to solve the high-dimensional PDE\, to compare the performance of the ada ptive method with a deep learning-based approach.\n DTSTART:20230213T213000Z DTEND:20230213T223000Z LOCATION:Room 1104\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Weiqi Wang (Concordia University) URL:/mathstat/channels/event/weiqi-wang-concordia-univ ersity-345859 END:VEVENT END:VCALENDAR