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Related papers: Optimization of Nonlinear Turbulence in Stellarato…

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This paper proposes an approach to perform travel demand calibration for high-resolution stochastic traffic simulators. It employs abundant travel times at the path-level, departing from the standard practice of resorting to scarce…

Emerging Technologies · Computer Science 2025-01-10 Chao Zhang , Yechen Li , Neha Arora , Damien Pierce , Carolina Osorio

In this work, a comparison of the global gyrokinetic codes EUTERPE and GENE-3D in stellarator configurations of LHD and W7-X is carried out. In linear simulations with adiabatic electrons, excellent agreement is found in the mode numbers,…

Plasma Physics · Physics 2023-08-15 E. Sánchez , A. Bañón Navarro , F. Wilms , M. Borchardt , R. Kleiber , F. Jenko

The present work considers diffusive shock acceleration at non-relativistic shocks using a system of stochastic differential equations (SDE) equivalent to the Fokker-Planck equation. We compute approximate solutions of the transport of…

Astrophysics · Physics 2007-05-23 A. Marcowith , J. G. Kirk

We present and discuss a variance-reduced stochastic particle method for simulating the relaxation-time model of the Boltzmann transport equation. The present paper focuses on the dilute gas case, although the method is expected to directly…

Computational Physics · Physics 2009-05-15 Nicolas G. Hadjiconstantinou , Gregg A. Radtke , Lowell L. Baker

Understanding the locality of high-temperature plasma energy deposition on material surfaces in fusion reactors is critical for design. Here, we utilize the Gyrokinetic ElectroMagnetic turbulence including X-points (GEMX) simulation,…

We present an efficient discontinuous Galerkin scheme for simulation of the incompressible Navier-Stokes equations including laminar and turbulent flow. We consider a semi-explicit high-order velocity-correction method for time integration…

Numerical Analysis · Mathematics 2017-08-15 Benjamin Krank , Niklas Fehn , Wolfgang A. Wall , Martin Kronbichler

Nonlinear simulations of Alfv\'en modes (AM) driven by energetic particles (EP) in the presence of turbulence are performed with the gyrokinetic particle-in-cell code ORB5. The AMs carry a heat flux, and consequently they nonlinearly modify…

A scale-resolving simulation methodology that includes stochastic energy backscatter is incorporated into a proprietary block-structured compressible flow solver. Particular attention is devoted to the discretisation of the convective terms…

Fluid Dynamics · Physics 2025-11-12 Angelo Passariello , Pietro Catalano , Carmine De Lucia , Renato Tognaccini

We propose a model independent framework for generating SPX and VIX risk scenarios based on a joint optimal transport calibration of their market smiles. Starting from the entropic martingale optimal transport formulation of Guyon, we…

Computational Finance · Quantitative Finance 2026-03-20 Charlie Che , Hanxuan Lin , Yudong Yang , Guofan Hu , Lei Fang

The first experimental campaigns of Wendelstein 7-X (W7-X) have shown that turbulence plays a decisive role in the performance of neoclassically optimized stellarators. This stresses the importance of understanding microturbulence from the…

Mesoscopic numerical simulations provide a unique approach for the quantification of the chemical influences on red blood cell functionalities. The transport Dissipative Particles Dynamics (tDPD) method can lead to such effective multiscale…

Computational Physics · Physics 2017-06-07 Ansel L. Blumers , Yu-Hang Tang , Zhen Li , Xuejin Li , George E. Karniadakis

In this work we investigate stochastic non-convex optimization problems where the objective is an expectation over smooth loss functions, and the goal is to find an approximate stationary point. The most popular approach to handling such…

Optimization and Control · Mathematics 2021-11-02 Kfir Y. Levy , Ali Kavis , Volkan Cevher

Non-Gaussian statistics are a challenge for data assimilation. Linear methods oversimplify the problem, yet fully nonlinear methods are often too expensive to use in practice. The best solution usually lies between these extremes.…

Computation · Statistics 2026-03-20 Berent Å. S. Lunde , Maximilian Ramgraber

Non-linear controller is preferred to linear controller due to non-linear operation of DSTATCOM. System dynamic can be improved by regulating and fixing the capacitor DC voltage in DSTATCOM. The nonlinear control is based on exact…

Systems and Control · Computer Science 2013-03-22 Ramesh Kumar , Dilawar Hussain , Ruchita

The accurate numerical simulation of turbulent incompressible flows is a challenging topic in computational fluid dynamics. For discretisation methods to be robust in the under-resolved regime, mass conservation as well as energy stability…

Computational Physics · Physics 2025-10-20 Niklas Fehn , Martin Kronbichler , Christoph Lehrenfeld , Gert Lube , Philipp W. Schroeder

Strongly nonlinear flows, which commonly arise in geophysical and engineering turbulence, are characterized by persistent and intermittent energy transfer between various spatial and temporal scales. These systems are difficult to model and…

Dynamical Systems · Mathematics 2022-01-25 Hassan Arbabi , Themistoklis Sapsis

This manuscript presents GPU optimizations for the 2D Hierarchical Poincar\'e-Steklov (HPS) discretization scheme. HPS is a multi-domain spectral collocation method that combines high-order discretizations with direct solvers to accurately…

Numerical Analysis · Mathematics 2025-04-22 Anna Yesypenko , Per-Gunnar Martinsson

We formulate and implement the Euler equations with SGS dynamics and provide numerical tests of an SGS turbulence energy model that predicts the turbulent pressure of unresolved velocity fluctuations and the rate of dissipation for highly…

Astrophysics of Galaxies · Physics 2015-05-20 W. Schmidt , C. Federrath

The paper studies the optimal density steering problem for nonlinear continuous-time stochastic systems. To accurately capture nonlinear dynamics in high-uncertainty regions that deviate significantly from a nominal linearization point, we…

Systems and Control · Electrical Eng. & Systems 2026-04-27 Mattia Mosso , George Rapakoulias , Yue Guan , Panagiotis Tsiotras

Recent advances have shown that the circuit simulation algorithms that allow for solving highly nonlinear circuits of over one billion variables can be applicable to power system simulation and optimization problems through the use of an…

Signal Processing · Electrical Eng. & Systems 2019-04-11 Marko Jereminov , Athanasios Terzakis , Martin Wagner , Amritanshu Pandey , Larry Pileggi