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This thesis presents an experimental study of the inverse energy cascade as it occurs in an electromagnetically forced soap film. It focuses on characterizing important features of the inverse cascade such as it's range, how energy is…

Fluid Dynamics · Physics 2007-05-23 Michael K. Rivera

Advanced kinetic theory with the Boltzmann-Curtiss equation provides a promising tool for polyatomic gas flows, especially for fluid flows containing inner structures, such as turbulence, polyatomic gas flows and others. Although a…

Fluid Dynamics · Physics 2018-02-14 James Chen

We consider random flights of point particles inside $n$-dimensional channels of the form $\mathbb{R}^{k} \times \mathbb{B}^{n-k}$, where $\mathbb{B}^{n-k}$ is a ball of radius $r$ in dimension $n-k$. The particle velocities immediately…

Probability · Mathematics 2018-07-02 Timothy Chumley , Renato Feres , Hong-Kun Zhang

The classical Prats' problem of flow instability in a horizontal porous channel saturated by a fluid subject to a buoyancy force is reconsidered. In the original formulation, the driving buoyancy force results from thermal diffusion. This…

Fluid Dynamics · Physics 2026-01-01 A. Barletta

We introduce diffusion geometry as a new framework for geometric and topological data analysis. Diffusion geometry uses the Bakry-Emery $\Gamma$-calculus of Markov diffusion operators to define objects from Riemannian geometry on a wide…

Metric Geometry · Mathematics 2024-07-03 Iolo Jones

Single-file systems, in which particles diffuse in narrow channels while not overtaking each other, is a fundamental model for the tracer subdiffusion observed in confined geometries, such as in zeolites or carbon nanotubes. Twenty years…

Statistical Mechanics · Physics 2024-05-27 Aurélien Grabsch , Olivier Bénichou

Accurate modeling of gas flow through porous media is critical for many technological applications, including reservoir performance prediction, carbon capture and sequestration, and fuel cells and batteries. However, such modeling remains…

Numerical Analysis · Mathematics 2026-03-13 V. S. Maduru , K. B. Nakshatrala

Experiments and numerical simulations were conducted to investigate the dispersion of turbulent jets issuing from realistic pipe geometries. The effect of jet densities and Reynolds numbers on vertical buoyant jets were investigated, as…

Fluid Dynamics · Physics 2018-11-15 Majid Soleimani Nia , Brian Maxwell , Peter Oshkai , Nedjib Djilali

Diffusion generative models unlock new possibilities for inverse problems as they allow for the incorporation of strong empirical priors in scientific inference. Recently, diffusion models are repurposed for solving inverse problems using…

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

Most of the physically based techniques for rendering translucent objects use the diffusion theory of light scattering in turbid media. The widely used dipole diffusion model (Jensen et al. 2001) applies the diffusion-theory formula derived…

Graphics · Computer Science 2010-11-16 Konstantin Kolchin

The purpose of this paper is to study transport equations on the unit tangent bundle of closed oriented Riemannian surfaces and to connect these to the transport twistor space of the surface (a complex surface naturally tailored to the…

Differential Geometry · Mathematics 2024-01-29 Jan Bohr , Thibault Lefeuvre , Gabriel P. Paternain

In this paper we consider a representative a priori unstable Hamiltonian system with 2+1/2 degrees of freedom, to which we apply the geometric mechanism for diffusion introduced in the paper Delshams et al., Mem. Amer. Math. Soc. 2006, and…

Dynamical Systems · Mathematics 2010-07-19 Amadeu Delshams , Gemma Huguet

Simultaneous use of partial differential equations in conjunction with data analysis has proven to be an efficient way to obtain the main parameters of various phenomena in different areas, such as medical, biological, and ecological. In…

Analysis of PDEs · Mathematics 2023-06-02 Sophie M. Moufawad , Nabil R. Nassif , Faouzi Triki

Diffusion probabilistic models excel at sampling new images from learned distributions. Originally motivated by drift-diffusion concepts from physics, they apply image perturbations such as noise and blur in a forward process that results…

Image and Video Processing · Electrical Eng. & Systems 2024-06-07 Pascal Peter

We solve an inverse problem for fluid particle pair-statistics: we show that a time sequence of probability density functions (PDF's) of separations can be exactly reproduced by solving the diffusion equation with a suitable time-dependent…

Fluid Dynamics · Physics 2015-06-16 Gregory L. Eyink , Damien Benveniste

Moisture diffusion in polymers and bio-based materials frequently exhibits non-Fickian behavior that cannot be described by classical diffusion models. The Langmuir model, which accounts for the coexistence of mobile and bound water…

Materials Science · Physics 2026-05-28 Corentin Guigot , Romain Grangeat , Gilles-Alexis Renaut

Mass transport of impurities immersed in a confined quasi-two-dimensional moderately dense granular gas of inelastic hard spheres is studied. The effect of the confinement on granular particles is modeled through a collisional model (the…

Soft Condensed Matter · Physics 2024-12-31 Rubén Gómez González , Vicente Garzó , Ricardo Brito , Rodrigo Soto

The penetration of atomic hydrogen through defect-free graphene was generally predicted to have a barrier of at least several eV, which is much higher than the 1 eV barrier measured for hydrogen-gas permeation through pristine graphene…

Materials Science · Physics 2023-07-26 Wenqi Xiong , Weiqing Zhou , Pengzhan Sun , Shengjun Yuan

We present the detailed analysis of the diffusive transport of spatially inhomogeneous fluid mixtures and the interplay between structural and dynamical properties varying on the atomic scale. The present treatment is based on different…

Mesoscale and Nanoscale Physics · Physics 2011-05-19 Umberto Marini Bettolo Marconi , Simone Melchionna