[Retracted] Prediction of Chemical Corrosion Rate and Remaining Life of Buried Oil and Gas Pipelines in Changqing Gas Field

Table 2

Folding cross-validation of specific divisions with green synthesis and metal oxide composites.

Number of crossovers	The training set	The verification set	The test set
1st time	5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16	1, 2, 3, 4
2nd time	1, 2, 3, 4, 9, 10, 11, 12, 13, 14, 15, 16	5, 6, 7, 8	17, 18, 19, 20
3rd time	1, 2, 3, 4, 5, 6, 7, 8, 13, 14, 15, 16	9, 10, 11, 12
4th time	1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12	13, 14, 15, 16