Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fast modeling of turbulent transport in fusion plasmas using neural
  networks   We present an ultrafast neural network (NN) model, QLKNN, which predicts core
tokamak transport heat and particle fluxes. QLKNN is a surrogate model based on
a database of 300 million flux calculations of the quasilinear gyrokinetic
transport model QuaLiKiz. The database covers a wide range of realistic tokamak
core parameters. Physical features such as the existence of a critical gradient
for the onset of turbulent transport were integrated into the neural network
training methodology. We have coupled QLKNN to the tokamak modelling framework
JINTRAC and rapid control-oriented tokamak transport solver RAPTOR. The coupled
frameworks are demonstrated and validated through application to three JET
shots covering a representative spread of H-mode operating space, predicting
turbulent transport of energy and particles in the plasma core. JINTRAC-QLKNN
and RAPTOR-QLKNN are able to accurately reproduce JINTRAC-QuaLiKiz T i,e and n
e profiles, but 3 to 5 orders of magnitude faster. Simulations which take hours
are reduced down to only a few tens of seconds. The discrepancy in the final
source-driven predicted profiles between QLKNN and QuaLiKiz is on the order
1%-15%. Also the dynamic behaviour was well captured by QLKNN, with differences
of only 4%-10% compared to JINTRAC-QuaLiKiz observed at mid-radius, for a study
of density buildup following the L-H transition. Deployment of neural network
surrogate models in multi-physics integrated tokamak modelling is a promising
route towards enabling accurate and fast tokamak scenario optimization,
Uncertainty Quantification, and control applications.

23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph