English
Related papers

Related papers: An adaptive Newton-based free-boundary Grad-Shafra…

200 papers

The Scaled Boundary Finite Element Method is a novel semi-analytical method jointly developed by Chongmin Song and John P Wolf to solve problems in elastodynamics and allied problems in civil engineering. This novel method has been recently…

Computational Physics · Physics 2007-05-23 V. S. Prasanna Rajan

A system of partial differential equations representing stochastic neural fields was recently proposed with the aim of modelling the activity of noisy grid cells when a mammal travels through physical space. The system was rigorously…

Analysis of PDEs · Mathematics 2023-07-18 José Antonio Carrillo , Pierre Roux , Susanne Solem

Fourth-order differential equations play an important role in many applications in science and engineering. In this paper, we present a three-field mixed finite-element formulation for fourth-order problems, with a focus on the effective…

Numerical Analysis · Mathematics 2022-10-13 Patrick E. Farrell , Abdalaziz Hamdan , Scott P. MacLachlan

A hybrid spectral/finite-element code is developed to numerically solve the resistive finite-pressure magnetohydrodynamic equilibria without the necessity of postulating nested magnetic flux surfaces in the non-axisymmetric toroidal…

Plasma Physics · Physics 2024-12-30 Jian Zhang , Ping Zhu , Chris C. Hegna

We propose an open-boundary molecular dynamics method in which an atomistic system is in contact with an infinite particle reservoir at constant temperature, volume and chemical potential. In practice, following the Hamiltonian adaptive…

Statistical Mechanics · Physics 2020-06-24 Maziar Heidari , Kurt Kremer , Ramin Golestanian , Raffaello Potestio , Robinson Cortes-Huerto

In this work, the matrix-free solution of quasi-static phase-field fracture problems is further investigated. More specifically, we consider a quasi-monolithic formulation in which the irreversibility constraint is imposed with a…

Numerical Analysis · Mathematics 2024-08-27 Leon Maximilian Kolditz , Thomas Wick

The modeling of electric machines and power transformers typically involves systems of nonlinear magnetostatics or -quasistatics, and their efficient and accurate simulation is required for the reliable design, control, and optimization of…

Numerical Analysis · Mathematics 2024-08-23 Herbert Egger , Felix Engertsberger , Bogdan Radu

The Vlasov-Poisson system describes the time evolution of a plasma in the so-called collisionless regime. The investigation of a high-temperature plasma that is influenced by an exterior magnetic field is one of the most significant aspects…

Optimization and Control · Mathematics 2024-07-11 Jan Bartsch , Patrik Knopf , Stefania Scheurer , Jörg Weber

The Poisson-Boltzmann equation is widely used to model molecular electrostatics; however, it is usually solved in linearised form because the sinh nonlinearity is challenging, limiting its applicability in highly charged systems such as…

Computational Physics · Physics 2026-04-20 Mauricio Guerrero-Montero , Michal Bosy , Christopher D. Cooper

This paper provides a rigorous analysis of boundary element methods for the magnetic field integral equation on Lipschitz polyhedra. The magnetic field integral equation is widely used in practical applications to model electromagnetic…

Numerical Analysis · Mathematics 2024-09-12 Van Chien Le , Kristof Cools

This paper presents a new method for synthesizing stochastic control Lyapunov functions for a class of nonlinear stochastic control systems. The technique relies on a transformation of the classical nonlinear Hamilton-Jacobi-Bellman partial…

Optimization and Control · Mathematics 2017-09-07 Yoke Peng Leong , Matanya B. Horowitz , Joel W. Burdick

We propose a necessary and sufficient condition for the well-posedness of the linear non-homogeneous Grad moment equations in half-space. The Grad moment system is based on Hermite expansion and regarded as an efficient reduction model of…

Analysis of PDEs · Mathematics 2022-09-13 Ruo Li , Yichen Yang

A free-boundary, axisymmetric magnetohydrodynamic (MHD) equilibrium code, pyIPREQ, has been developed for Tokamak plasmas using finite difference and Green's function approach. The code builds upon the foundational frameworks of the PEST…

Plasma Physics · Physics 2025-10-06 Udaya Maurya , Amit K. Singh , Suman Aich , Jagabandhu Kumar , Rohit Kumar , Daniel Raju

We present an application of a nonstandard approximate method---the finite-rank approximation---to solving the time-independent Schr\"odinger equation for a bound-state problem. The method is illustrated on the example of a…

Quantum Physics · Physics 2014-09-18 Vladimir B. Belyaev , Andrej Babič

This paper presents a total Lagrangian mixed Petrov-Galerkin finite element formulation that provides a computationally efficient approach for analyzing Cosserat rods that is free of singularities and locking. To achieve a singularity-free…

We propose a unified derivative-free proximal Newton-type algorithm framework for solving composite optimization problems formulated as the sum of a black-box function and a known regularization term. We establish the iteration and oracle…

Optimization and Control · Mathematics 2026-05-08 Zekun Liu , Jinyan Fan

We propose a high order adaptive-rank implicit integrators for stiff time-dependent PDEs, leveraging extended Krylov subspaces to efficiently and adaptively populate low-rank solution bases. This allows for the accurate representation of…

Numerical Analysis · Mathematics 2024-04-05 Hamad El Kahza , William Taitano , Jing-Mei Qiu , Luis Chacón

A neural network solving Grad-Shafranov equation constrained with measured magnetic signals to reconstruct magnetic equilibria in real time is developed. Database created to optimize the neural network's free parameters contain off-line…

A procedure that allows study of unstable stability of a boundary layer between plasma and a magnetic field has been developed. Layer equilibrium for one reason or another is not set but follows from strict solution of kinetic equation with…

Plasma Physics · Physics 2010-05-25 V. V. Lyahov , V. M. Neshchadim

We study the free boundary problem for a plasma-vacuum interface in ideal incompressible magnetohydrodynamics. Unlike the classical statement when the vacuum magnetic field obeys the div-curl system of pre-Maxwell dynamics, to better…

Analysis of PDEs · Mathematics 2020-07-15 Alessandro Morando , Paolo Secchi , Yuri Trakhinin , Paola Trebeschi