Analysis of nuclear fusion reactor discharge simulations using METIS
Bibliographic record
Abstract
The Nuclear Engineering Department of UPC has the need of a nuclear fusion plasma simulator for its research activities and educational tasks. For many years, PRETOR has been the program used for this purpose, but it has become obsolete. Nowadays there are more modern simulation codes for fusion reactor’s plasma shots, like CRONOS and METIS. Due to the complexity of CRONOS, METIS was more suitable. The Nuclear Engineering Section of UPC has been authorised by ITER Organisation to use METIS for educational and research purposes after the signing of an agreement named "Agreement on Cooperation on the ITER Modelling and Analysis Suite (IMAS) and Related Repositories by Universitat Politècnica de Catalunya". This project has gotten inside METIS program, to analyse the obtained simulations on fusion plasma, trying to understand some pieces of code as well. METIS is a code based on MATLAB, combined with some modules programmed with Fortran, C and C++, developed by J.F. Artaud from the Institute for Magnetic Fusion Research, in France. Despite being METIS a very powerful tool on the simulation of fusion reactors with a great quantity of applications, as it is a restricted program only available for researchers from the same field, it does not offer enough help information for those who begin to work with it. This document includes a brief introduction on fusion physics, the principles on magnetic confinement reactors and the presentation of some different integrated modelling codes for fusion plasma. In order to complement the METIS help guide, we have used the knowledge acquired during our work to prepare a draft manual that we hope to be useful whenever it is intended to work on a teaching practices program. During this process we have tried to understand on which models the program is based, getting to analyse the source code, study and compare simulations. Furthermore, a great amount of work done in this project has been focused on the development of a setup of MATLAB functions designed to make easier the study of METIS outputs. This has permitted us to outline an example on how it would be possible to incorporate new functionalities inside METIS source code
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.004 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".