Fig. 4

Cross-project data distribution comparison using a combination of violin and box plot, where CRS: Cutterhead speed, PRchd: Cutterhead penetration rate, RMR: Rock mass rating, and PRnet: Net penetration rate.

Cross-project data distribution comparison using a combination of violin and box plot, where CRS: Cutterhead speed, PRchd: Cutterhead penetration rate, RMR: Rock mass rating, and PRnet: Net penetration rate.