# Development of Prediction Method for Dimensional Stability of 3D-Printed Objects
## 3 Results
### ANOVA Test  
In this study, the main and interaction effects of design parameters on MSDE were investigated by using the ANOVA model. The ANOVA results for supporting and non-supporting cases are listed in Tables 11 and 12. Visual representations of the main and interaction effects of design parameters for supportive cases are presented in Figures 6 and 7, respectively. Correspondingly, Figures 8 and 9 illustrate the effects on MSDE for non-supporting cases.  
Figure 8: Main effects plot for non-supporting cases.  
Figure 6: Main effects plot for supporting cases.  
Figure 7: Interaction plot for supporting cases.  
As illustrated in Figure 6, an increase in the inclination angle (Angle) led to a reduction in MSDE. Adjusting the inclination angle from 15\({}^{\circ}\) to 30\({}^{\circ}\) and from 30\({}^{\circ}\) to 45\({}^{\circ}\) resulted in MSDE reductions of 16.88% and 35.32%, respectively. Conversely, an increase in support spacing (Support) and layer thickness (L.T) was associated with an increase in MSDE. Specifically, increasing support spacing from 5 mm to 10 mm and from 10 mm to 15 mm led to MSDE increases of 82.31% and 25.81%, respectively. Similarly, elevating layer thickness from 0.2 mm to 0.4 mm and from 0.4 mm to 0.6 mm resulted in MSDE increases of 61.56% and 22.68%, respectively. The MSDE exhibited a declining trend with rising raster angle (R.A) until 45\({}^{\circ}\), beyond which an increase was observed. Notably, the lowest MSDE was observed at a raster angle of 45\({}^{\circ}\). Based on the main effect analysis, the optimal combination entailed an inclination angle of 45\({}^{\circ}\), support spacing of 5 mm, layer thickness of 0.2 mm, and a raster angle of 45\({}^{\circ}\). As depicted in Figure 7, the analysis indicated no significant interactions between parameters.  
Table 12 presents the ANOVA results for non-supporting cases, outlining the statistical significance of main and interaction effects. Layer thickness and raster angle both exhibited significant effects on MSDE, with \(p\)-values smaller than 0.05. The \(p\)-value for the inclination angle was relatively close to the 0.05 threshold, suggesting a comparatively moderate level of significance. Regarding interactions, all terms had \(p\)-values exceeding 0.05.  
Figure 8 depicts how an increase in inclination angle and layer thickness contributed to the MSDE increase. For instance, increasing the inclination angle from 60\({}^{\circ}\) to 75\({}^{\circ}\) led to a 20.98% MSDE increase. Similarly, augmenting layer thickness from 0 mm to 0.4 mm and from 0.4 mm to 0.6 mm resulted in MSDE increases of 150.93% and 46.71%, respectively. The MSDE followed a decreasing trend until a raster angle of 45\({}^{\circ}\), beyond which it increased. Specifically, adjusting the raster angle from 0\({}^{\circ}\) to 45\({}^{\circ}\) resulted in a 61.33% MSDE reduction, followed by an 89.59% MSDE increase upon further adjustment to 90\({}^{\circ}\). Based on the main effect analysis, the optimal combination consisted of a 60\({}^{\circ}\) inclination angle, 0.2 mm layer thickness, and a 45\({}^{\circ}\) raster angle. Figure 9 highlighted interaction effects, though no significant interactions were observed.