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Materials Science in Additive Manufacturing                            Interpretable GP melt track prediction



            sparsity. In contrast, the SVR model achieves superior   height, and deviation predictions for the other groups
            performance by balancing global trend capture with   were 8.06%, 14.45%, and 9.59% (for 240 W-660 mm/s)
            moderate local mutation sensitivity. The DGP-based melt   and 8.13%, 11.60%, and 9.39% (for 290 W-760 mm/s),
            track geometric feature prediction model is guided by   with average relative errors of 8.69%, 14.02%, and
            multilayer non-linear hidden variable transfer and physical   9.73%, respectively.
            principles, ensuring the capability to accommodate
            sudden local offsets while predicting global trends. This   The DGP model demonstrates the highest accuracy
            approach  mitigates  purely  data-driven  overfitting  risks,   in melt track width prediction. However, deviation
            enforces physical law compliance in predictions, and   predictions deteriorate significantly, while height
            enhances  model interpretability. Due  to its  multilayer   predictions  display  the  poorest  performance.  Notably,
                                                                                            th
            architecture, uncertainty propagates  layer-wise through   under higher energy density, the 24  group (refers to 340
            kernel functions from initially hidden variables, resulting   W-960 mm/s) exhibited larger average relative errors than
            in marginally expanded confidence intervals compared to   the other two groups. This degradation may be attributable
            traditional GP models.                             to three factors: (i) the melt pool behavioral pattern
              However, the impact of the transmission of       changes  under  high  power,  invalidating  Equation  X  to
            uncertain hidden variables is significantly reduced   this process parameter; (ii) the assumption of Equation IX
            through the introduction of physical constraints. The   on the height is relatively simple and does not sufficiently
            predicted average width of the melt track was 123.55   take into account the actual physical process; and (iii) the
            μm and the average height was 28.29 μm, comparable   height of the melt track is sensitive to changes in the melt
            to the actual geometry of the melt track by 9.89% and   pool aspect ratio, and the optimal time lag value of the
            16.03%, respectively, with a relative error of 10.21% in   melt pool aspect ratio is 2, resulting in deterioration in the
            the average deviation. The relative errors in the width,   prediction effect.
                        A                                           B


















            Figure 17. Classification results without oversampling: (A) evaluation metrics; and (B) confusion matrix

                         A                                          B

















            Figure 18. Classification results with oversampling: (A) evaluation metrics, and (B) confusion matrix



            Volume 4 Issue 3 (2025)                         14                        doi: 10.36922/MSAM025200030
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