@article{bibcite_8825, author = {S. Kajita and I. Sho and H. Tanaka and D. Nishijima and K. Fujii and H. J. van der Meiden and N. Ohno}, title = {Use of machine learning for a helium line intensity ratio method in Magnum-PSI}, abstract = {Optical emission spectroscopy (OES) of helium (He) line intensities has been used to measure the electron density, n e, and temperature, T e, in various plasma devices. In this study, a neural network with five hidden layers is introduced to model the relation between the OES data and n e/T e from laser Thomson scattering in the linear plasma device Magnum-PSI and compared to multiple regression analysis. It is shown that the neural network reduces the residual errors of prediction values (n e and T e) less than half those of the multiple regression analysis in the ranges of 2 {\texttimes} 10 18\<n e\<8{\texttimes}10 20m-3 and 0.1\<T e\<4 eV. We checked two different data splitting methods for training and validation data, i.e., with and without considering the unit of discharge. A comparison of the splitting methods suggests that the residual error will decrease to \~{}10\% even for a new discharge data when accumulating a sufficient data set. }, year = {2022}, journal = {Nuclear Materials and Energy}, volume = {33}, pages = {101281}, month = {10/2022}, doi = {10.1016/j.nme.2022.101281}, language = {eng}, }