“…The p values of AB, BC, A 2 , and C 2 were 0.10, 0.14, 0.94, and 0.22, respectively, which are nonsignificant influencing factors, so were removed from the table to ensure the accuracy of the model; in addition, in the expression of the bead height model, A, B, C, AC, and B 2 were found to be significant influencing factors, with p values of AB, BC, A 2 , and C 2 are 0.59, 0.41, 0.12, and 0.09, respectively, making them nonsignificant influencing factors. To ensure the accuracy of the model, these factors were also removed from the model [22]. Thus, the coded value regression equations with the surfacing speed, surfacing voltage, and surfacing current as the variables, and the bead height and the dilution rate as the response values were obtained, namely,…”