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Related papers: The curved Mimetic Finite Difference method: allow…

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Anomaly detection is a complex problem due to the ambiguity in defining anomalies, the diversity of anomaly types (e.g., local and global defect), and the scarcity of training data. As such, it necessitates a comprehensive model capable of…

Computer Vision and Pattern Recognition · Computer Science 2025-11-06 Byeongchan Lee , John Won , Seunghyun Lee , Jinwoo Shin

It is known that the solution of a conservative steady-state two-sided fractional diffusion problem can exhibit singularities near the boundaries. As consequence of this, and due to the conservative nature of the problem, we adopt a finite…

Numerical Analysis · Mathematics 2022-09-20 Marco Donatelli , Rolf Krause , Mariarosa Mazza , Ken Trotti

Introducing flexibility in the time-discretisation mesh can improve convergence and computational time when solving differential equations numerically, particularly when the solutions are discontinuous, as commonly found in control problems…

Optimization and Control · Mathematics 2023-06-27 Lucian Nita , Eduardo M. G. Vila , Marta A. Zagorowska , Eric C. Kerrigan , Yuanbo Nie , Ian McInerney , Paola Falugi

Mimetic methods discretize divergence by restricting the Gauss theorem to mesh cells. Because point clouds lack such geometric entities, construction of a compatible meshfree divergence remains a challenge. In this work, we define an…

Numerical Analysis · Mathematics 2020-03-18 Nathaniel Trask , Pavel Bochev , Mauro Perego

In wave propagation problems, finite difference methods implemented on staggered grids are commonly used to avoid checkerboard patterns and to improve accuracy in the approximation of short-wavelength components of the solutions. In this…

Numerical Analysis · Mathematics 2026-01-15 Micol Bassanini , Simone Deparis , Paolo Ricci

We introduce a family of hybrid discretisations for the numerical approximation of optimal control problems governed by the equations of immiscible displacement in porous media. The proposed schemes are based on mixed and discontinuous…

Numerical Analysis · Mathematics 2019-05-02 S. Kumar , R. Ruiz Baier , R. Sandilya

Fitted finite element methods are constructed for a singularly perturbed convection-diffusion problem in two space dimensions. Exponential splines as basis functions are combined with Shishkin meshes to obtain a stable parameter-uniform…

Numerical Analysis · Mathematics 2023-10-03 Alan F. Hegarty , Eugene O'Riordan

We propose finite difference methods for degenerate fully nonlinear elliptic equations and prove the convergence of the schemes. Our focus is on the pure equation and a related free boundary problem of transmission type. The cornerstone of…

Numerical Analysis · Mathematics 2025-06-04 Edgard A. Pimentel , Ercília Sousa

Diffusion models have achieved huge empirical success in data generation tasks. Recently, some efforts have been made to adapt the framework of diffusion models to discrete state space, providing a more natural approach for modeling…

Machine Learning · Statistics 2024-02-15 Hongrui Chen , Lexing Ying

Discrete differential geometry aims to develop discrete equivalents of the geometric notions and methods of classical differential geometry. In this survey we discuss the following two fundamental Discretization Principles: the…

Differential Geometry · Mathematics 2015-06-26 Alexander I. Bobenko , Yuri B. Suris

We consider a model convection-diffusion problem and present our recent numerical and analysis results regarding mixed finite element formulation and discretization in the singular perturbed case when the convection term dominates the…

Numerical Analysis · Mathematics 2024-02-07 Constantin Bacuta , Daniel Hayes , Tyler O'Grady

This paper presents compact, symmetric, and high-order finite difference methods (FDMs) for the variable Poisson equation on a $d$-dimensional hypercube. Our scheme produces a symmetric linear system: an important property that does not…

Numerical Analysis · Mathematics 2025-11-14 Qiwei Feng , Bin Han , Michelle Michelle , Jiwoon Sim

We propose a novel formulation for parametric finite element methods to simulate surface diffusion of closed curves, which is also called as the curve diffusion. Several high-order temporal discretizations are proposed based on this new…

Numerical Analysis · Mathematics 2024-08-27 Harald Garcke , Wei Jiang , Chunmei Su , Ganghui Zhang

We demonstrate a method for filtering images defined on curved surfaces embedded in 3D. Applications are noise removal and the creation of artistic effects. Our approach relies on in-surface diffusion: we formulate Weickert's edge/coherence…

Numerical Analysis · Mathematics 2014-04-08 Emma Naden , Thomas März , Colin B. Macdonald

Dense vertex-to-vertex correspondence between 3D faces is a fundamental and challenging issue for 3D&2D face analysis. While the sparse landmarks have anatomically ground-truth correspondence, the dense vertex correspondences on most facial…

Computer Vision and Pattern Recognition · Computer Science 2021-09-24 Zhenfeng Fan , Silong Peng , Shihong Xia

Asymptotic net is an important concept in discrete differential geometry. In this paper, we show that we can associate affine discrete geometric concepts to an arbitrary non-degenerate asymptotic net. These concepts include discrete affine…

Differential Geometry · Mathematics 2020-01-15 Marcos Craizer

Recent literature has effectively leveraged diffusion models trained on continuous variables as priors for solving inverse problems. Notably, discrete diffusion models with discrete latent codes have shown strong performance, particularly…

Computer Vision and Pattern Recognition · Computer Science 2025-09-22 Naoki Murata , Chieh-Hsin Lai , Yuhta Takida , Toshimitsu Uesaka , Bac Nguyen , Stefano Ermon , Yuki Mitsufuji

Grids are a general representation for capturing regularly-spaced information, but since they are uniform in space, they cannot dynamically allocate resolution to regions with varying levels of detail. There has been some exploration of…

Graphics · Computer Science 2026-01-12 Julian Knodt , Seung-Hwan Baek

Various bias-correction methods such as EXTRA, gradient tracking methods, and exact diffusion have been proposed recently to solve distributed {\em deterministic} optimization problems. These methods employ constant step-sizes and converge…

Machine Learning · Computer Science 2023-07-19 Kun Yuan , Sulaiman A. Alghunaim , Bicheng Ying , Ali H. Sayed

This papers deals with a construction and convergence analysis of a finite difference scheme for solving time-fractional porous medium equation. The governing equation exhibits both nonlocal and nonlinear behaviour making the numerical…

Numerical Analysis · Mathematics 2019-04-05 Łukasz Płociniczak