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We propose a globally divergence conforming discontinuous Galerkin (DG) method on Cartesian meshes for {\em curl-type hyperbolic conservation} laws based on directly evolving the face and cell moments of the Raviart-Thomas approximation…

Numerical Analysis · Mathematics 2018-09-11 Praveen Chandrashekar

Stochastic gradient methods (SGMs) are the predominant approaches to train deep learning models. The adaptive versions (e.g., Adam and AMSGrad) have been extensively used in practice, partly because they achieve faster convergence than the…

Optimization and Control · Mathematics 2022-04-14 Yangyang Xu , Yibo Xu , Yonggui Yan , Colin Sutcher-Shepard , Leopold Grinberg , Jie Chen

To extend the discrete velocity method (DVM) and unified methods to more realistic boundary conditions, a Cercignani-Lampis (CL) boundary with different momentum and thermal energy accommodations is proposed and integrated into the DVM…

Fluid Dynamics · Physics 2025-04-07 Jianfeng Chen , Sha Liu , Rui Zhang , Hao Jin , Congshan Zhuo , Ming Fang , Yanguang Yang , Chengwen Zhong

This paper extends the high-order compact gas-kinetic scheme (CGKS) to compressible flow simulations on a rotating coordinate frame. The kinetic equation with the inclusion of centrifugal and Coriolis acceleration is used in the…

Computational Physics · Physics 2022-11-01 Yue Zhang , Xing Ji , Kun Xu

Discrepancy measures between probability distributions are at the core of statistical inference and machine learning. In many applications, distributions of interest are supported on different spaces, and yet a meaningful correspondence…

Machine Learning · Computer Science 2021-11-23 Zhengxin Zhang , Youssef Mroueh , Ziv Goldfeld , Bharath K. Sriperumbudur

In this paper, we study the asymptotic dynamics of global solutions to damped Klein-Gordon equations in inhomogeneous mediums (KGI). In the defocusing case, we prove for any initial data, the solution is globally define in forward time and…

Analysis of PDEs · Mathematics 2016-12-20 Ze Li , Lifeng Zhao

We propose a simple and easy-to-implement scheme for a renormalon-free gluon condensate (GC) matrix element, which is analogous to implementations of short-distance heavy-quark mass renormalization schemes existing in the literature already…

High Energy Physics - Phenomenology · Physics 2022-07-13 Miguel A. Benitez-Rathgeb , Diogo Boito , Andre H. Hoang , Matthias Jamin

We study a quasi-two-dimensional electrostatic drift kinetic system as a model for near-marginal ion temperature gradient (ITG) driven turbulence. A proof is given of the nonlinear stability of this system under conditions of linear…

Plasma Physics · Physics 2015-04-16 G. G. Plunk

We introduce a deep learning accelerated methodology to solve PDE-based Bayesian inverse problems with guaranteed accuracy. This is motivated by the ill-posed problem of inferring a spatio-temporal heat-flux parameter known as the Biot…

Numerical Analysis · Mathematics 2023-06-06 Teo Deveney , Eike Mueller , Tony Shardlow

We use a generic framework, namely the gradient discretisation method (GDM), to propose a unified numerical analysis for general time-dependent convection-diffusion-reaction models. We establish novel results for convergence rates of…

Numerical Analysis · Mathematics 2025-07-03 Hasan Alzubaidi , Yahya Alnashri

This paper presents a dissipativeness analysis of a quadrature method of moments (called HyQMOM) for the one-dimensional BGK equation. The method has exhibited its good performance in numerous applications. However, its mathematical…

Numerical Analysis · Mathematics 2024-06-21 Ruixi Zhang , Yihong Chen , Qian Huang , Wen-An Yong

A paradigm based on the absolute equilibrium of Galerkin-truncated inviscid systems to aid in understanding turbulence [T.-D. Lee, "On some statistical properties of hydrodynamical and magnetohydrodynamical fields," Q. Appl. Math. 10, 69…

Plasma Physics · Physics 2010-11-30 Jian-Zhou Zhu , Gregory W. Hammett

Gaze estimation methods commonly use facial appearances to predict the direction of a person gaze. However, previous studies show three major challenges with convolutional neural network (CNN)-based, transformer-based, and contrastive…

Computer Vision and Pattern Recognition · Computer Science 2026-05-04 Xinyuan Zhao , Yihang Wu , Ahmad Chaddad , Sarah A. Alkhodair , Reem Kateb

We introduce Midpoint Generative Models (MGM), a principled framework for training one-step generative models. MGM is based on a simple symmetry of Flow Matching with linear interpolation: when the two endpoint distributions coincide, the…

Machine Learning · Computer Science 2026-05-29 Daniil Shlenskii , Nikita Gushchin , Lev Novitskiy , Dmitry V. Dylov , Alexander Korotin

Accurate prediction of aerothermal loads in hypersonic flows is critical yet challenging due to the coupling of Shock-Wave/Boundary-Layer Interactions (SBLI) and thermal non-equilibrium. This work presents the development of a…

Fluid Dynamics · Physics 2026-02-10 Xingjian Gao , Hualin Liu , Fengxiang Zhao , Xing Ji

Work presented in this paper describes a general algorithm and its finite element implementation for performing concurrent multiple sub-domain simulations in linear structural dynamics. Using this approach one can solve problems in which…

Numerical Analysis · Mathematics 2013-12-25 Tejas Ruparel , Azim Eskandarian , James Lee

A comprehensive gyrokinetic simulation model has been implemented in the global toroidal gyrokinetic code (GTC) and verified for studying low-frequency waves and turbulence in magnetic fusion plasmas by treating all kinetic-MHD processes on…

We develop a novel Monte Carlo strategy for the simulation of the Boltzmann-BGK model with both low-collisional and high-collisional regimes present. The presented solution to maintain accuracy in low-collisional regimes and remove…

Numerical Analysis · Mathematics 2020-12-23 Bert Mortier , Martine Baelmans , Giovanni Samaey

This work is devoted to the numerical implementation of the quantum Bhatnagar- Gross-Krook (BGK) model for gas mixtures consisting of classical and quantum particles (fermions, bosons). We consider the model proposed by Bae, Klingenberg,…

Numerical Analysis · Mathematics 2025-02-04 Gi-Chan Bae , Marlies Pirner , Sandra Warnecke

Microinstabilities drive turbulent fluctuations in inhomogeneous, magnetized plasmas. In the context of magnetic confinement fusion devices, this leads to an enhanced transport of particles, momentum, and energy, thereby degrading…

Plasma Physics · Physics 2024-03-20 Georgia Acton , Michael Barnes , Sarah Newton , Hanne Thienpondt