English
Related papers

Related papers: On a minimum set of equations for parameterisation…

200 papers

Mathematical modeling of real-world physical systems requires the consistent combination of a multitude of physical laws and phenomenological models. This challenging task can be greatly simplified by hierarchically decomposing systems into…

Systems and Control · Electrical Eng. & Systems 2025-03-03 Markus Lohmayer , Owen Lynch , Sigrid Leyendecker

Global Climate Models (GCMs) are the primary tool to simulate climate evolution and assess the impacts of climate change. However, they often operate at a coarse spatial resolution that limits their accuracy in reproducing local-scale…

Atmospheric and Oceanic Physics · Physics 2023-08-04 Jose González-Abad , Álex Hernández-García , Paula Harder , David Rolnick , José Manuel Gutiérrez

A good representation of mesoscopic fluids is required to combine with molecular simulations at larger length and time scales (De Fabritiis {\it et. al}, Phys. Rev. Lett. 97, 134501 (2006)). However, accurate computational models of the…

Fluid Dynamics · Physics 2015-06-26 G. De Fabritiis , M. Serrano , R. Delgado-Buscalioni , P. V. Coveney

In this contribution we propose reduced order methods to fast and reliably solve parametrized optimal control problems governed by time dependent nonlinear partial differential equations. Our goal is to provide a tool to deal with the time…

Numerical Analysis · Mathematics 2023-08-08 Francesco Ballarin , Gianluigi Rozza , Maria Strazzullo

The estimation of commuting flows at different spatial scales is a fundamental problem for different areas of study. Many current methods rely on parameters requiring calibration from empirical trip volumes. Their values are often not…

Physics and Society · Physics 2014-07-24 Yingxiang Yang , Carlos Herrera , Nathan Eagle , Marta C. Gonzalez

The generalized transport equations for a consistent description of kinetic and hydrodynamic processes in dense gases and liquids are considered. The inner structure of the generalized transport kernels for these equations is established.…

Statistical Mechanics · Physics 2015-06-16 B. Markiv , I. Omelyan , M. Tokarchuk

Adaptive resolution schemes allow the simulation of a molecular fluid treating simultaneously different subregions of the system at different levels of resolution. In this work we present a new scheme formulated in terms of a global…

Active matter has been widely studied in recent years because of its rich phenomenology, whose mathematical understanding is still partial. We present some results, based on [8, 17] linking microscopic lattice gases to their macroscopic…

Mathematical Physics · Physics 2021-08-10 Clément Erignoux

Semi-implicit time-stepping schemes for atmosphere and ocean models require elliptic solvers that work efficiently on modern supercomputers. This paper reports our study of the potential computational savings when using mixed precision…

Computational Physics · Physics 2022-10-05 Jan Ackmann , Peter D. Düben , Tim N. Palmer , Piotr K. Smolarkiewicz

We propose a regularization framework inspired by thermodynamic work for guiding pre-trained probability flow generative models (e.g., continuous normalizing flows or diffusion models) by minimizing excess work, a concept rooted in…

Several approximations are made to study the microcanonical formalism that are valid in the thermodynamics limit. Usually it is assumed that: 1)Stirling approximation can be used to evaluate the number of microstates; 2) the surface entropy…

General Physics · Physics 2015-10-07 E. N. Miranda , Dalia S. Bertoldi

Modeling transition-continuum hypersonic flows poses significant challenges due to thermodynamic nonequilibrium and the associated breakdown of the continuum assumption. Standard continuum models such as the Navier-Stokes equations are…

Fluid Dynamics · Physics 2025-06-18 Mikolaj Kryger , Jonathan F. MacArt

Models of complex dynamical systems like the Earth's climate often involve large numbers of uncertain parameters. Comprehensive exploration of the parameter space is typically prohibitive due to excessive computational costs. Systematic…

Atmospheric and Oceanic Physics · Physics 2026-03-27 Daniel Pals , Sebastian Bathiany , Richard Wood , Joel Kuettel , Niklas Boers

A general formalism is developed for constructing modified Hamiltonian dynamical systems which preserve a canonical equilibrium distribution by adding a time evolution equation for a single additional thermostat variable. When such systems…

Statistical Mechanics · Physics 2015-12-09 John D. Ramshaw

An error estimate for a canonical discretization of the harmonic map heat flow into spheres is derived. The numerical scheme uses standard finite elements with a nodal treatment of linearized unit-length constraints. The analysis is based…

Numerical Analysis · Mathematics 2022-08-18 Sören Bartels , Balázs Kovács , Zhangxian Wang

We recently developed a new approach to get a stabilized image from a sequence of frames acquired through atmospheric turbulence. The goal of this algorihtm is to remove the geometric distortions due by the atmosphere movements. This method…

Computer Vision and Pattern Recognition · Computer Science 2024-11-06 Yu Mao , Jerome Gilles

Shallow flows are governed by the Navier-Stokes equations. They are commonly modelled using the shallow water equations, a great simplification of the Navier-Stokes equations, which often yields inaccurate results. For that reason, a model…

Fluid Dynamics · Physics 2025-11-21 Vilém Rožek

Coarse-grained (CG) models are often parametrized to reproduce one-dimensional structural correlation functions of an atomically-detailed model along the degrees of freedom governing each interaction potential. While cross correlations…

Soft Condensed Matter · Physics 2019-12-02 Svenja J. Woerner , Tristan Bereau , Kurt Kremer , Joseph F. Rudzinski

Numerical simulations for flow and transport in subsurface porous media often prove computationally prohibitive due to property data availability at multiple spatial scales that can vary by orders of magnitude. A number of model order…

Numerical Analysis · Mathematics 2018-03-13 Gurpreet Singh , Wingtat Leung , Mary F. Wheeler

The goal of this paper is to set up a framework designed to take into account the characteristics of sediment particles when transported by water. Our protocol consists in describing the characteristics of sediment particles via an…

Analysis of PDEs · Mathematics 2009-03-04 Emmanuel Frenod