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Scene flow estimation, which aims to predict per-point 3D displacements of dynamic scenes, is a fundamental task in the computer vision field. However, previous works commonly suffer from unreliable correlation caused by locally constrained…

Computer Vision and Pattern Recognition · Computer Science 2024-05-13 Jiuming Liu , Guangming Wang , Weicai Ye , Chaokang Jiang , Jinru Han , Zhe Liu , Guofeng Zhang , Dalong Du , Hesheng Wang

A diffused-interface approach based on the Allen-Cahn phase field equation is developed within a high-order Discontinuous Galerkin framework. The interface capturing technique is based on the balance between explicit diffusion and…

Fluid Dynamics · Physics 2023-06-09 Niccolò Tonicello , Matthias Ihme

The numerical simulation of large-scale multiphase flow in porous media is of considerable importance across various application fields, particularly in the petroleum industry. The fully implicit method is preferred in reservoir simulations…

Numerical Analysis · Mathematics 2026-04-13 Shizhe Li , Li Zhao , Chen-Song Zhang

Diffusion models (DMs) have shown promising results on single-image super-resolution and other image-to-image translation tasks. Benefiting from more computational resources and longer inference times, they are able to yield more realistic…

Computer Vision and Pattern Recognition · Computer Science 2024-10-24 Yuanting Fan , Chengxu Liu , Nengzhong Yin , Changlong Gao , Xueming Qian

We study passive scalar mixing by parallel shear flows in the presence of weak molecular diffusion. We recover the sharp uniform-in-diffusivity mixing rate for shear flows with finitely many critical points, recently proven in [1]. Our…

Analysis of PDEs · Mathematics 2026-03-11 Kyle L. Liss , Kunhui Luan

In this paper, an algorithm is presented to calculate the transition rates between adjacent mesoscopic subvolumes in the presence of flow and diffusion. These rates can be integrated in stochastic simulations of reaction-diffusion systems…

Chemical Physics · Physics 2020-04-24 Adam Noel , Dimitrios Makrakis

We investigate two-phase flow in porous media and derive a two-scale model, which incorporates pore-scale phase distribution and surface tension into the effective behavior at the larger Darcy scale. The free-boundary problem at the pore…

Analysis of PDEs · Mathematics 2023-07-03 Mathis Kelm , Carina Bringedal , Bernd Flemisch

We develop a numerical a framework to study phoretic particle dynamics in two dimensions. The particles are modeled as chemically active rigid circles, which can emit or absorb a solute into surrounding fluid. The interaction between…

Soft Condensed Matter · Physics 2025-12-16 Zhe Gou , Alexander Farutin , Chaouqi Misbah

The simulation of stochastic reaction-diffusion systems using fine-grained representations can become computationally prohibitive when particle numbers become large. If particle numbers are sufficiently high then it may be possible to…

Quantitative Methods · Quantitative Biology 2020-10-02 Christian A. Yates , Adam George , Armand Jordana , Cameron A. Smith , Andrew B. Duncan , Konstantinos C. Zygalakis

We reconstruct the velocity field of incompressible flows given a finite set of measurements. For the spatial approximation, we introduce the Sparse Fourier divergence-free (SFdf) approximation based on a discrete $L^2$ projection. Within…

Fluid Dynamics · Physics 2021-10-13 Luis Espath , Dmitry Kabanov , Jonas Kiessling , Raúl Tempone

This work investigates the long-time asymptotic behavior of a diffusing passive scalar advected by fluid flow in a straight channel with a periodically varying cross-section. The goal is to derive an asymptotic expansion for the scalar…

Fluid Dynamics · Physics 2026-04-09 Lingyun Ding

Accurate prediction of the macroscopic flow parameters needed to describe flow in porous media relies on a good knowledge of flow field distribution at a much smaller scale---in the pore spaces. The extent of the inertial effect in the pore…

Fluid Dynamics · Physics 2016-06-09 Bagus Putra Muljadi

In this paper, we propose an improved phase field model for interface capturing in simulating two-phase incompressible flows. The model incorporates a second-order diffusion term, which utilizes a nonlinear coefficient to assess the degree…

Fluid Dynamics · Physics 2025-01-20 Jing-Wei Chen , Chun-Yu Zhang , Hao-Ran Liu , Hang Ding

We explain how the invariant subspace method can be extended to a scalar and coupled system of time-space fractional partial differential equations. The effectiveness and applicability of the method have been illustrated through time-space…

Analysis of PDEs · Mathematics 2020-07-17 P Prakash

Diffusion models have recently emerged as a powerful technique in image generation, especially for image super-resolution tasks. While 2D diffusion models significantly enhance the resolution of individual images, existing diffusion-based…

Computer Vision and Pattern Recognition · Computer Science 2024-11-27 Bohao Chen , Yanchao Zhang , Yanan Lv , Hua Han , Xi Chen

A variety of simulation methodologies have been used for modeling reaction-diffusion dynamics -- including approaches based on Differential Equations (DE), the Stochastic Simulation Algorithm (SSA), Brownian Dynamics (BD), Green's Function…

Chemical Physics · Physics 2021-05-21 Marcus Thomas , Russell Schwartz

Super-resolution (SR) techniques based on deep learning have recently emerged as a promising approach to enhance the spatial resolution of computational fluid dynamics simulations while containing computational cost. In this paper, we…

Fluid Dynamics · Physics 2026-04-13 Armin Sheidani , Michele Girfoglio , Annalisa Quaini , Gianluigi Rozza

Inverting an evolving diffusive scalar field to reconstruct the underlying velocity field is an underdetermined problem. Here we show, however, that for two-dimensional incompressible flows, this inverse problem can still be uniquely solved…

Fluid Dynamics · Physics 2019-06-26 Arjun Sharma , Irina I. Rypina , Ruth Musgrave , George Haller

The dispersion of a passive scalar in a fluid through the combined action of advection and molecular diffusion is often described as a diffusive process, with an effective diffusivity that is enhanced compared to the molecular value.…

Fluid Dynamics · Physics 2015-06-18 P. H. Haynes , J. Vanneste

We present a novel multiscale numerical approach that combines parallel-in-time computation with hybrid domain adaptation for linear collisional kinetic equations in the diffusive regime. The method addresses the computational challenges of…

Numerical Analysis · Mathematics 2025-11-18 Tino Laidin