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A promising method for calculating free energy differences Delta F is to generate non-equilibrium data via ``fast-growth'' simulations or experiments -- and then use Jarzynski's equality. However, a difficulty with using Jarzynski's…

Computational Physics · Physics 2007-05-23 F. Marty Ytreberg , Daniel M. Zuckerman

A type of adaptive finite element method for the eigenvalue problems is proposed based on the multilevel correction scheme. In this method, adaptive finite element method to solve eigenvalue problems involves solving associated boundary…

Numerical Analysis · Mathematics 2012-01-12 Hehu Xie

This paper proposes a virtual element method (VEM) combined with a second-order implicit-explicit scheme based on the scalar auxiliary variable (SAV) method for the incompressible magnetohydrodynamics (MHD) equations. We employ the BDF2…

Numerical Analysis · Mathematics 2024-10-25 Xiaojing Dong , Yunqing Huang , Tianwen Wang

X-ray observations of shock-heated plasmas, such as those found in supernova remnants, often exhibit features of temperature and ionization non-equilibrium. For accurate interpretation of these observations, proper calculations of the…

High Energy Astrophysical Phenomena · Physics 2024-10-02 Yuken Ohshiro , Shunsuke Suzuki , Yoshizumi Okada , Hiromasa Suzuki , Hiroya Yamaguchi

Non-equilibrium effects are studied using a full Lorentz-invariant formalism. Our analysis shows that in reactions considered here, no global or local equilibrium is reached. The heavier masses are found to be equilibrated more than the…

Nuclear Theory · Physics 2016-09-08 Rajeev K. Puri , E. Lehmann , Amand Faessler , S. W. Huang

Large-scale eigenvalue problems pose a significant challenge to classical computers. While there are efficient quantum algorithms for unitary or Hermitian matrices, eigenvalue problems for non-normal matrices remain open in quantum…

Quantum Physics · Physics 2026-03-25 Honghong Lin , Yun Shang

We present a new hybrid algorithm implemented in the code CHIEF (Code Hybrid with Inertial Electron Fluid) for simulations of electron-ion plasmas. The algorithm treats the ions kinetically, modeled by the Particle-in-Cell (PiC) method, and…

Plasma Physics · Physics 2018-02-27 P. A. Muñoz , N. Jain , P. Kilian , J. Büchner

Computer simulations of model systems are widely used to explore striking phenomena in promising applications spanning from physics, chemistry, biology, to materials science and engineering. The long range electrostatic interactions between…

Computational Physics · Physics 2020-07-21 Sheng-Chun Yang , Bin Li , You-Liang Zhu , Aatto Laaksonen , Yong-Lei Wang

A novel orthogonalization-free method together with two specific algorithms are proposed to solve extreme eigenvalue problems. On top of gradient-based algorithms, the proposed algorithms modify the multi-column gradient such that earlier…

Numerical Analysis · Mathematics 2021-10-15 Weiguo Gao , Yingzhou Li , Bichen Lu

Modern depth sensors can generate a huge number of 3D points in few seconds to be latter processed by Localization and Mapping algorithms. Ideally, these algorithms should handle efficiently large sizes of Point Clouds under the assumption…

Robotics · Computer Science 2025-02-04 Gonzalo Ferrer , Dmitrii Iarosh , Anastasiia Kornilova

Superlevel partitioning is combined with a simple relaxation procedure to construct an iterative technique for solving equations of statistical equilibrium. In treating an $N$-level model atom, the technique avoids the $N^{3}$ scaling in…

Astrophysics · Physics 2009-11-06 L. B. Lucy

The eigenvalue shift technique is the most well-known and fundamental tool for matrix computations. Applications include the search of eigeninformation, the acceleration of numerical algorithms, the study of Google's PageRank. The shift…

Numerical Analysis · Mathematics 2013-03-04 Chun-Yueh Chiang , Matthew M. Lin

It is significant and challenging to solve eigenvalue problems of partial differential operators when many highly accurate eigenpair approximations are required. The adaptive finite element discretization based parallel orbital-updating…

Numerical Analysis · Mathematics 2025-09-24 Xiaoying Dai , Yan Li , Bin Yang , Aihui Zhou

This study evaluates numerical discretization methods for the Single Particle Model (SPM) used in electrochemical modeling. The methods include the Finite Difference Method (FDM), spectral methods, Pad\'e approximation, and parabolic…

Systems and Control · Electrical Eng. & Systems 2025-06-03 Feng Guo , Luis D. Couto

The ENUF method, i.e., Ewald summation based on the Non-Uniform FFT technique (NFFT), is implemented in Dissipative Particle Dynamics (DPD) simulation scheme to fast and accurately calculate the electrostatic interactions at mesoscopic…

Computational Physics · Physics 2013-03-20 Yong-Lei Wang , Aatto Laaksonen , Zhong-Yuan Lu

The paper proposes a method to obtain the optimal basis set for solving the self consistent field (SCF) equations for large atomic systems in order to calculate the energy barriers in tunneling structures, with higher accuracy and speed.…

Mathematical Physics · Physics 2009-12-16 Sever Spanulescu

This study presents a novel optimisation technique for atomic structure calculations using the Flexible Atomic Code, focussing on complex multielectron systems relevant to $r$-process nucleosynthesis and kilonova modelling. We introduce a…

From characterizing the speed of a thermal system's response to computing natural modes of vibration, eigenvalue analysis is ubiquitous in engineering. In spite of this, eigenvalue problems have received relatively little treatment compared…

Numerical Analysis · Mathematics 2025-06-06 Conor Rowan , John Evans , Kurt Maute , Alireza Doostan

The uncertainty quantification of Darcy flows using history matching is important for the evaluation and prediction of subsurface reservoir performance. Conventional methods aim to obtain the maximum a posterior or maximum likelihood…

Numerical Analysis · Mathematics 2025-04-16 Zhao Zhang , Xinpeng Li , Menghan Li , Jiayu Zhai , Piyang Liu , Xia Yan , Kai Zhang

In this paper, we propose an adaptive high-order method for hyperbolic systems of conservation laws. The proposed method is based on a dual formulation approach: Two numerical solutions, corresponding to conservative and nonconservative…

Numerical Analysis · Mathematics 2026-01-29 Alina Chertock , Qingcheng Fu , Alexander Kurganov , Lorenzo Micalizzi