In this study, the TTS trend of the Korean surveillance test results was analyzed using a nonlinear regression model and a mixed-effect model based on the power function. The nonlinear regression model yielded a similar exponent as the power function in the fluence compared with 2. The mixed-effect model had a higher value of the exponent and showed superior goodness of fit compared with the nonlinear regression model. Compared with and , the mixed-effect model provided a more accurate prediction of the TTS. | Statistical analysis on the fluence factor of surveillance test data of Korean nuclear power plants
