English
Related papers

Related papers: Statistical coarse-graining as an approach to mult…

200 papers

We present a theoretical approach to scale the artificially fast dynamics of simulated coarse-grained polymer liquids down to its realistic value. As coarse-graining affects entropy and dissipation, two factors enter the rescaling:…

Soft Condensed Matter · Physics 2015-05-27 I. Y. Lyubimov , J. McCarty , A. Clark , M. G. Guenza

The construction of valid and flexible cross-covariance functions is a fundamental task for modeling multivariate space-time data arising from climatological and oceanographical phenomena. Indeed, a suitable specification of the covariance…

Statistics Theory · Mathematics 2017-11-23 Alfredo Alegría , Emilio Porcu , Reinhard Furrer , Jorge Mateu

Mixing grains with different properties is a remarkably challenging process, relevant to many industrial applications. Rotating drums have been used extensively as model systems to study granular media flow and mixing and segregation.…

Soft Condensed Matter · Physics 2018-09-05 Claudia Piacenza , Marco Marconati , Colin Hare , Andrea C. Santomaso , Marco Ramaioli

In this paper we present a variational technique that handles coarse-graining and passing to a limit in a unified manner. The technique is based on a duality structure, which is present in many gradient flows and other variational…

Analysis of PDEs · Mathematics 2017-03-06 Manh Hong Duong , Agnes Lamacz , Mark A. Peletier , Upanshu Sharma

The paper is devoted to the magnetic properties of isolated mesoscopic grains. We demonstrate that under very general conditions the electron - electron interactions in such grains can be taken into account by a simple interaction…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 I. L. Kurland , I. L. Aleiner , B. L. Altshuler

Due to a ferromagnetic in-chain coupling between Co$^{3+}$ ions at trigonal sites, chains Co$_2$O$_6$ are considered as large rigid spin moments. The antiferromagnetic Ising model on the triangular lattice is applied to describe an…

Strongly Correlated Electrons · Physics 2009-11-11 Yuri B. Kudasov

We analyze the thermal magnetization reversal processes in magnetic grains. Two experiments are carried out: swtiching time and switching field experiments. In both cases, we find that the simulated behavior is coherent with existing…

Condensed Matter · Physics 2009-10-28 R. Mélin

Atomistic modelling of magnetic materials provides unprecedented detail about the underlying physical processes that govern their macroscopic properties, and allows the simulation of complex effects such as surface anisotropy, ultrafast…

The random-anisotropy Heisenberg model is numerically studied on lattices containing over ten million spins. The study is focused on hysteresis and metastability due to topological defects, and is relevant to magnetic properties of…

Statistical Mechanics · Physics 2015-12-09 Thomas C. Proctor , Eugene M. Chudnovsky , Dmitry A. Garanin

Continuum models of dislocation plasticity require constitutive closure assumptions, e.g., by relating details of the dislocation microstructure to energy densities. Currently, there is no systematic way for deriving or extracting such…

Materials Science · Physics 2021-05-26 Hengxu Song , Nina Gunkelmann , Giacomo Po , Stefan Sandfeld

We present results obtained with various types of heterogeneous nucleation in a kinetic Ising model of magnetization switching in single-domain ferromagnetic nanoparticles. We investigate the effect of the presence of the system boundary…

Condensed Matter · Physics 2009-10-28 M. Kolesik , H. L. Richards , M. A. Novotny , Per Arne Rikvold , Per-Anker Lindgard

Several mechanisms have been proposed to explain the alignment of grains with the interstellar magnetic field, including paramagnetic dissipation, radiative torques, and supersonic gas-grain streaming. These must compete with disaligning…

Astrophysics · Physics 2008-11-26 Joseph C. Weingartner

Machine learning for the parameterization of subgrid-scale processes in climate models has been widely researched and adopted in a few models. A key challenge in developing data-driven parameterization schemes is how to properly represent…

Atmospheric and Oceanic Physics · Physics 2024-02-29 L. Minah Yang , Edwin P. Gerber

Numerous molecular systems, including solutions, proteins, and composite materials, can be modeled using mixed-resolution representations, of which the quantum mechanics/molecular mechanics (QM/MM) approach has become the most widely used.…

Chemical Physics · Physics 2018-01-17 Anton V. Sinitskiy , Gregory A. Voth

With the advent of multi-coil imaging and compressed sensing, a number of model based reconstruction algorithms have been created. They incorporate a multitude of different regularization functions based on physics, observed phenomenology,…

Image and Video Processing · Electrical Eng. & Systems 2023-02-03 Nicholas Dwork , Ethan M. I. Johnson , Daniel O'Connor , Jeremy W. Gordon , Adam B. Kerr , Corey A. Baron , John M. Pauly , Peder E. Z. Larson

Given a set of inelastic material models, a microstructure, a macroscopic structural geometry, and a set of boundary conditions, one can in principle always solve the governing equations to determine the system's mechanical response.…

Computational Engineering, Finance, and Science · Computer Science 2023-06-27 Ghina Jezdan , Sanjay Govindjee , Klaus Hackl

The dynamical cluster approximation (DCA) and its DCA$^+$ extension use coarse-graining of the momentum space to reduce the complexity of quantum many-body problems, thereby mapping the bulk lattice to a cluster embedded in a dynamical…

Strongly Correlated Electrons · Physics 2016-05-04 P. Staar , M. Jiang , U. R. Hähner , T. C. S. Schulthess , T. A. Maier

We consider a Gaussian process formulation of the multiple kernel learning problem. The goal is to select the convex combination of kernel matrices that best explains the data and by doing so improve the generalisation on unseen data.…

Machine Learning · Statistics 2011-10-25 Cedric Archambeau , Francis Bach

We formulated a technique which combines the first-principles, micromagnetic and microstructural calculations and allows us to study the nature of hysteretic phenomena in hard magnets. Two distinct sources of coercivity in polytwinned CoPt…

Materials Science · Physics 2009-11-07 K. D. Belashchenko , V. P. Antropov

In this paper we investigate the approximation properties of the coarse-graining procedure applied to kinetic Monte Carlo simulations of lattice stochastic dynamics. We provide both analytical and numerical evidence that the hierarchy of…

Numerical Analysis · Mathematics 2007-05-23 Markos A Katsoulakis , Petr Plechac , Alexandros Sopasakis