English
Related papers

Related papers: Multidimensional staggered grid residual distribut…

200 papers

We report a linear-scaling random Green's function (rGF) method for large-scale electronic structure calculation. In this method, the rGF is defined on a set of random states to stochastically express the density matrix, and rGF is…

Mesoscale and Nanoscale Physics · Physics 2024-03-05 Mingfa Tang , Chang Liu , Aixia Zhang , Qingyun Zhang , Shengjun Yuan , Youqi Ke

There has been widespread interest in the use of grid-level storage to handle the variability from increasing penetrations of wind and solar energy. This problem setting requires optimizing energy storage and release decisions for anywhere…

Optimization and Control · Mathematics 2016-05-06 Tsvetan Asamov , Daniel F. Salas , Warren B. Powell

In this contribution, we extend the hybridization framework for the Hodge Laplacian [Awanou et al., Hybridization and postprocessing in finite element exterior calculus, 2023] to port-Hamiltonian systems describing linear wave propagation…

Numerical Analysis · Mathematics 2025-02-25 Andrea Brugnoli , Ramy Rashad , Yi Zhang , Stefano Stramigioli

State redistribution (SRD) is a recently developed technique for stabilizing cut cells that result from finite-volume embedded boundary methods. SRD has been successfully applied to a variety of compressible and incompressible flow…

Numerical Analysis · Mathematics 2023-09-13 Isabel Barrio Sanchez , Ann S. Almgren , John B. Bell , Marc T. Henry de Frahan , Weiqun Zhang

We propose a new stochastic optimization framework for empirical risk minimization problems such as those that arise in machine learning. The traditional approaches, such as (mini-batch) stochastic gradient descent (SGD), utilize an…

Machine Learning · Statistics 2020-02-04 Kenji Kawaguchi , Haihao Lu

This paper theoretically reanalyzes the convergence of the mini-batch stochastic gradient descent (SGD) for a structured minimization problem involving a finite-sum function with its gradient being stochastically approximated, and an…

Optimization and Control · Mathematics 2026-04-07 Runze Li , Jintao Xu , Wenxun Xing

This paper studies the physical-constraints-preserving (PCP) Lagrangian finite volume schemes for one- and two-dimensional special relativistic hydrodynamic (RHD) equations. First, the PCP property (i.e. preserving the positivity of the…

Numerical Analysis · Mathematics 2024-12-20 Dan Ling , Junming Duan , Huazhong Tang

The multinomial logistic regression (MLR) model is widely used in statistics and machine learning. Stochastic gradient descent (SGD) is the most common approach for determining the parameters of a MLR model in big data scenarios. However,…

Optimization and Control · Mathematics 2021-05-03 Borja Sánchez-López , Jesus Cerquides

Stochastic gradient descent~(SGD) and its variants have been the dominating optimization methods in machine learning. Compared to SGD with small-batch training, SGD with large-batch training can better utilize the computational power of…

Machine Learning · Statistics 2024-04-16 Shen-Yi Zhao , Chang-Wei Shi , Yin-Peng Xie , Wu-Jun Li

Inspired by dynamic programming, we propose Stochastic Virtual Gradient Descent (SVGD) algorithm where the Virtual Gradient is defined by computational graph and automatic differentiation. The method is computationally efficient and has…

Machine Learning · Computer Science 2019-08-01 Zheng Li , Shi Shu

In this paper we propose a novel arbitrary high order accurate semi-implicit space-time discontinuous Galerkin method for the solution of the two dimensional incompressible Navier-Stokes equations on staggered unstructured triangular…

Numerical Analysis · Mathematics 2014-12-04 Maurizio Tavelli , Michael Dumbser

In this paper we propose a novel arbitrary high order accurate semi-implicit space-time DG method for the solution of the three-dimensional incompressible Navier-Stokes equations on staggered unstructured curved tetrahedral meshes. As…

Numerical Analysis · Mathematics 2016-06-22 Maurizio Tavelli , Michael Dumbser

Semi-Lagrangian methods have traditionally been developed in the framework of hyperbolic equations, but several extensions of the Semi-Lagrangian approach to diffusion and advection--diffusion problems have been proposed recently. These…

Numerical Analysis · Mathematics 2014-05-20 L. Bonaventura , R. Ferretti

A mass-preserving two-step Lagrange-Galerkin scheme of second order in time for convection-diffusion problems is presented, and convergence with optimal error estimates is proved in the framework of $L^2$-theory. The introduced scheme…

Numerical Analysis · Mathematics 2022-02-22 Kouta Futai , Niklas Kolbe , Hirofumi Notsu , Tasuku Suzuki

The paper describes an explicit multi-dimensional numerical scheme for Special Relativistic Two-Fluid Magnetohydrodynamics of electron-positron plasma and a suit of test problems. The scheme utilizes Cartesian grid and the third order WENO…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Maxim Barkov , Serguei S. Komissarov , Vitaly Korolev , Andrey Zankovich

I present a review of Smoothed Particle Hydrodynamics (SPH), with the aim of providing a mathematically rigorous, clear derivation of the algorithms from first principles. The method of discretising a continuous field into particles using a…

Instrumentation and Methods for Astrophysics · Physics 2010-10-05 Peter J. Cossins

We address the solution of the distributed control problem for the steady, incompressible Navier--Stokes equations. We propose an inexact Newton linearization of the optimality conditions. Upon discretization by a finite element scheme, we…

Numerical Analysis · Mathematics 2025-04-16 Santolo Leveque , Michele Benzi , Patrick E. Farrell

Most numerical schemes proposed for solving BGK models for rarefied gas dynamics are based on the discrete velocity approximation. Since such approach uses fixed velocity grids, one must secure a sufficiently large domain with fine velocity…

Numerical Analysis · Mathematics 2022-04-20 Sebastiano Boscarino , Seung Yeon Cho , Giovanni Russo

Despite the non-convex optimization landscape, over-parametrized shallow networks are able to achieve global convergence under gradient descent. The picture can be radically different for narrow networks, which tend to get stuck in…

Machine Learning · Statistics 2023-06-16 Rodrigo Veiga , Ludovic Stephan , Bruno Loureiro , Florent Krzakala , Lenka Zdeborová

Galerkin and Petrov-Galerkin projection-based reduced-order models (ROMs) of transient partial differential equations are typically obtained by performing a dimension reduction and projection process that is defined at either the spatially…

Numerical Analysis · Mathematics 2023-02-23 Eric Parish , Masayuki Yano , Irina Tezaur , Traian Iliescu