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We present TokaMind, an open-source foundation model framework for fusion plasma modeling, based on a Multi-Modal Transformer (MMT) and trained on heterogeneous tokamak diagnostics from the publicly available MAST dataset. TokaMind supports…

Ultra-cold atomic gases are unique in terms of the degree of controllability, both for internal and external degrees of freedom. This makes it possible to use them for the study of complex quantum many-body phenomena. However in many…

Quantum Physics · Physics 2020-09-30 Rick Mukherjee , Frederic Sauvage , Harry Xie , Robert Löw , Florian Mintert

We developed a parallel Bayesian optimization algorithm for large eddy simulations. These simulations challenge optimization methods because they take hours or days to compute, and their objective function contains noise as turbulent…

Fluid Dynamics · Physics 2014-11-04 Chaitanya Talnikar , Patrick Blonigan , Julien Bodart , Qiqi Wang

While fusion reactors known as tokamaks hold promise as a firm energy source, advances in plasma control, and handling of events where control of plasmas is lost, are needed for them to be economical. A significant bottleneck towards…

Plasma Physics · Physics 2023-11-01 Allen M. Wang , Darren T. Garnier , Cristina Rea

Real time control of many plasma parameters will be an essential aspect in the development of reliable high performance operation of Next Step Tokamaks. The main prerequisites for any feedback scheme are the precise real-time determination…

Many safety-critical real-world problems, such as autonomous driving and collaborative robots, are of a distributed multi-agent nature. To optimize the performance of these systems while ensuring safety, we can cast them as distributed…

Systems and Control · Electrical Eng. & Systems 2025-08-20 Abdullah Tokmak , Thomas B. Schön , Dominik Baumann

Learning-based techniques are increasingly effective at controlling complex systems using data-driven models. However, most work done so far has focused on learning individual tasks or control laws. Hence, it is still a largely unaddressed…

Systems and Control · Electrical Eng. & Systems 2020-05-08 Alexandre Capone , Armin Lederer , Jonas Umlauft , Sandra Hirche

Achieving controlled burning plasma in tokamaks requires precise regulation of external particle and energy sources to reach and maintain target core densities and temperatures. This work presents an inverse modeling approach using a…

Plasma Physics · Physics 2025-07-15 Zefang Liu , Weston M. Stacey

In policy learning for robotic manipulation, sample efficiency is of paramount importance. Thus, learning and extracting more compact representations from camera observations is a promising avenue. However, current methods often assume full…

Accelerator physics relies on numerical algorithms to solve optimization problems in online accelerator control and tasks such as experimental design and model calibration in simulations. The effectiveness of optimization algorithms in…

A properly designed controller can help improve the quality of experimental measurements or force a dynamical system to follow a completely new time-evolution path. Recent developments in deep reinforcement learning have made steep advances…

Statistical Mechanics · Physics 2025-02-26 Ruslan Mukhamadiarov

It is shown that a relevant control of Hamiltonian chaos is possible through suitable small perturbations whose form can be explicitly computed. In particular, it is possible to control (reduce) the chaotic diffusion in the phase space of a…

Chaotic Dynamics · Physics 2007-05-23 G. Ciraolo , F. Briolle , C. Chandre , E. Floriani , R. Lima , M. Vittot , M. Pettini , C. Figarella , P. Ghendrih

Probabilistic models such as Gaussian processes (GPs) are powerful tools to learn unknown dynamical systems from data for subsequent use in control design. While learning-based control has the potential to yield superior performance in…

Systems and Control · Electrical Eng. & Systems 2022-09-22 Alexander von Rohr , Matthias Neumann-Brosig , Sebastian Trimpe

Bayesian optimization works effectively optimizing parameters in black-box problems. However, this method did not work for high-dimensional parameters in limited trials. Parameters can be efficiently explored by nonlinearly embedding them…

Machine Learning · Computer Science 2022-06-14 Shoki Miyagawa , Atsuyoshi Yano , Naoko Sawada , Isamu Ogawa

Stochastic control with both inherent random system noise and lack of knowledge on system parameters constitutes the core and fundamental topic in reinforcement learning (RL), especially under non-episodic situations where online learning…

Systems and Control · Electrical Eng. & Systems 2019-06-24 Xin Huang , Duan Li , Daniel Zhuoyu Long

Autonomous methods to align beamlines can decrease the amount of time spent on diagnostics, and also uncover better global optima leading to better beam quality. The alignment of these beamlines is a high-dimensional, expensive-to-sample…

Bayesian hybrid models fuse physics-based insights with machine learning constructs to correct for systematic bias. In this paper, we compare Bayesian hybrid models against physics-based glass-box and Gaussian process black-box surrogate…

Optimization and Control · Mathematics 2019-12-16 Elvis A. Eugene , Xian Gao , Alexander W. Dowling

The dynamics of burning plasmas in tokamaks are crucial for advancing controlled thermonuclear fusion. This study applies the NeuralPlasmaODE, a multi-region multi-timescale transport model, to simulate the complex energy transfer processes…

Plasma Physics · Physics 2024-12-13 Zefang Liu , Weston M. Stacey

In the context of global gyrokinetic simulations of turbulence using a Particle-In-Cell framework, verifying the delta-f assumption with a fixed background distribution becomes challenging when determining quasi-steady state profiles…

Online field experiments are the gold-standard way of evaluating changes to real-world interactive machine learning systems. Yet our ability to explore complex, multi-dimensional policy spaces - such as those found in recommendation and…

Machine Learning · Statistics 2019-04-30 Benjamin Letham , Eytan Bakshy
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