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Eugenio Schuster

Publications and source records attributed to Eugenio Schuster.

2 recordsLinked to original sources

Rates of Convergence in Certain Native Spaces of Approximations used in Reinforcement Learning

This paper studies convergence rates for some value function approximations that arise in a collection of reproducing kernel Hilbert spaces (RKHS) $H(Ω)$. By casting an optimal control problem in a specific class of native spaces, strong rates of convergence are derived for the operator equation that enables offline approximations that appear in policy iteration. Explicit upper bounds on error in value function and controller approximations are derived in terms of power function $\mathcal{P}_{H,N}$ for the space of finite dimensional approximants $H_N$ in the native space $H(Ω)$. These bounds are geometric in nature and refine some well-known, now classical results concerning convergence of approximations of value functions.

eess.SY

Towards Control of Steady State Plasma on Tore Supra

The Tore Supra tokamak is the largest superconducting magnetic fusion facility, has been devoted to long-duration high-performance discharge research. With a steady-state magnetic field and water cooled plasma facing components, discharges up to 6 minutes 24 seconds duration with injected / extracted energy up to 1 GJ have been performed. The Tore Supra real time measurements and control (RTMC) system has been upgraded to address schemes dedicated to long pulse operation with simultaneous control of an increasing number of plasma parameters. This includes plasma equilibrium control with possible self calibration during the discharge, plasma density control with possible pellet injection, current profile control to avoid magneto-hydrodynamic (MHD) instabilities and infrared monitoring of plasma facing components preventing overheating. Most of these improvements are relevant to the tokamaks operation in a fully steady state regime.

physics.plasm-ph