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Related papers: Extending near-axis equilibria in DESC

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This report is dedicated to the construction and analysis of so-called Generalized Impedance Boundary Conditions (GIBCs) used in electromagnetic scattering problems from imperfect conductors as higher order approximations of a perfect…

Analysis of PDEs · Mathematics 2008-01-07 Houssem Haddar , Patrick Joly , Hoai Minh Nguyen

We provide an extension of the method of asymptotic decompositions of vector fields with finite-time singularities by applying the central extension technique of Poincar\'e to the dominant part of the vector field on approach to the…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Spiros Cotsakis

In this paper, we establish the sufficient conditions guaranteeing global uniform exponential stability, or at least global asymptotic stability, of all solutions for nonlinear dynamical systems, also known as global incremental stability…

Dynamical Systems · Mathematics 2022-07-06 Robert Vrabel

We present a new approach for computing approximate global minimizers to a large class of non-local pairwise interaction problems defined over probability distributions. The approach predicts candidate global minimizers, with a recovery…

Numerical Analysis · Mathematics 2017-10-04 Mahdi Bandegi , David Shirokoff

We describe an algorithm for constructing N-body realisations of equilibrium stellar systems. The algorithm complements existing orbit-based modelling techniques using linear programming or other optimization algorithms. The equilibria are…

Astrophysics · Physics 2015-06-24 D. Syer , S. Tremaine

This article is devoted to one particular case of using universal accelerated proximal envelopes to obtain computationally efficient accelerated versions of methods used to solve various optimization problem setups. In this paper, we…

Optimization and Control · Mathematics 2021-01-14 Dmitry Pasechnyuk , Anton Anikin , Vladislav Matyukhin

We apply Prediction-Based control (PBC) in order to stabilize globally a positive equilibrium of a planar Ricker's equation. We construct a closed invariant set in a strictly positive domain for the controlled map and derive conditions on…

Dynamical Systems · Mathematics 2025-12-12 Elena Braverman , Alexandra Rodkina

We develop the formalism of the first order near-axis expansion of the MHD equilibrium equations described in Garren & Boozer (1991), Plunk et al. (2019) and Plunk et al. (2021), for the case of a quasi-isodynamic, N-field period,…

Plasma Physics · Physics 2022-11-29 Katia Camacho Mata , Gabriel G. Plunk , Rogerio Jorge

In this paper, we investigate the asymptotic behaviors of the solutions of nonlinear dynamic systems nearby an equilibrium point, when the nominal parts are subject to non necessarily small perturbations. We show that, under some estimates…

Dynamical Systems · Mathematics 2020-08-07 Mondher Benjemaa , Wided Gouadri , Mohamed Ali Hammami

Calibration is a vital step in the development of rigorous digital models of diverse physical and chemical processes, yet one which is highly time- and labour-intensive. In this paper, we introduce a novel tool, Autonomous Calibration and…

In the context of global/goal-oriented error estimation applied to computational mechanics, the need to obtain reliable and guaranteed bounds on the discretization error has motivated the use of residual error estimators. These estimators…

Numerical Analysis · Mathematics 2017-04-25 Florent Pled , Ludovic Chamoin , Pierre Ladevèze

We introduce the concept of a control contraction metric, extending contraction analysis to constructive nonlinear control design. We derive sufficient conditions for exponential stabilizability of all trajectories of a nonlinear control…

Systems and Control · Computer Science 2017-02-09 Ian R. Manchester , Jean-Jacques E. Slotine

Many optimization problems can be naturally represented as (hyper) graphs, where vertices correspond to variables and edges to tasks, whose cost depends on the values of the adjacent variables. Capitalizing on the structure of the graph,…

Logic in Computer Science · Computer Science 2015-04-13 Nicklas Hoch , Ugo Montanari , Matteo Sammartino

In this paper, we discuss how to design the graph topology to reduce the communication complexity of certain algorithms for decentralized optimization. Our goal is to minimize the total communication needed to achieve a prescribed accuracy.…

Optimization and Control · Mathematics 2016-12-06 Yat-Tin Chow , Wei Shi , Tianyu Wu , Wotao Yin

Recent results in the literature have provided connections between the so-called turnpike property, near optimality of closed-loop solutions, and strict dissipativity. Motivated by applications in economics, optimal control problems with…

Optimization and Control · Mathematics 2022-02-18 Lars Grüne , Lisa Krügel

This talk provides a critical assessment of collisionless galactic dynamics, focusing on the interpretation and limitations of the collisionless Boltzmann equation and the physical mechanisms associated with collisionless relaxation.…

Astrophysics · Physics 2009-10-30 Henry E. Kandrup

In this paper, we propose a novel Spatial Balance Attention block for spatiotemporal forecasting. To strike a balance between obeying spatial proximity and capturing global correlation, we partition the spatial graph into a set of subgraphs…

Machine Learning · Computer Science 2025-09-24 Hongyi Chen , Xiucheng Li , Xinyang Chen , Jing Li , Kehai Chen , Liqiang Nie

An effective means to approximate an analytic, nonperiodic function on a bounded interval is by using a Fourier series on a larger domain. When constructed appropriately, this so-called Fourier extension is known to converge geometrically…

Numerical Analysis · Mathematics 2013-05-14 Ben Adcock , Daan Huybrechs , Jesus Martin-Vaquero

To build an economically viable stellarator, it is essential to find a configuration that satisfies a set of favorable properties to achieve efficient steady-state nuclear fusion. One such property is omnigenity, which ensures confinement…

Decentralized partially observable Markov decision processes (Dec-POMDPs) formalize the problem of designing individual controllers for a group of collaborative agents under stochastic dynamics and partial observability. Seeking a global…

Artificial Intelligence · Computer Science 2023-05-22 Yang You , Vincent Thomas , Francis Colas , Olivier Buffet