# New Possibilities of Using DEMATEL and ERPN in the New PFMEA Hybrid Model
## 3 Results and Discussion
### Hybrid Model PFMEA-DEMATEL-ERPN
#### 3.5.2 Prediction and Estimation of the Functionality of the Proposed Models  
Based on the location of the failure modes in the individual quadrants of the DEMATEL model digraph (Figure 2), we estimated the success of the used models that make up the resulting hybrid model.  
The location of the failure modes for the conventional PFMEA for which we proposed measures is shown in Figure 4. For each model, we divided the failure modes (for which we proposed measures) into cause and effect. At the same time, For each failure mode, we displayed the intensity of the relation to other failure modes. We have shown their quantity and intensity in Figure 4 (highlighted by blue arrows) and Table 12.  
Figure 4: _Cont_.  
The location of the failure modes for the DEMATEL model for which we proposed measures is shown in Figure 5.  
The location of the failure modes for the model with ERPN for which we proposed measures is shown in Figure 6.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Failure Mode** & \multirow{2}{*}{**Casal**} & \multirow{2}{*}{**Effect**} & \multicolumn{3}{c}{**Number of Bonds**} \\
**Model** & & & **Significant Intensity** & **Average Intensity** & **Low Intensity** \\ \hline Conventional PFMEA & 2 & 2 & 9 & 9 & 6 \\ DEMATEL & 4 & 0 & 9 & 17 & 13 \\ ERPN & 3 & 1 & 7 & 15 & 10 \\ \hline \hline \end{tabular}
\end{table}
Table 12: The number of bonds and their intensity for each model.  
Figure 4: Main failure modes of the conventional PFMEA and their relations on other failure model.  
Figure 5: Main failure modes in PFMEA combined with DEMATEL and their relations with the other failure modes.  
Based on Figures 4-6, we created Table 12.  
Discussion of Table 12:  
The DEMATEL model has all four failure modes (FM2, FM3, FM5, FM9) for which measures have been proposed, located in the first quadrant (Figure 4). All four failure modes are significant and causal, which means they also influence the emergence of other failure modes. If we, as an FMEA team, made the right decisions when creating the initial matrix of a given model, it should manifest itself as the model that manifests itself with the highest reduction in the monitored criteria. This is also indicated by the fact that these four failure modes influence the other 9 failure modes (with repetition) with a significant relation and influence 17 failure modes by the average intensity relation.  
The ERPN model has two failure modes (FM2, FM5) in the first quadrant (Figure 5). The FM12 failure mode is in the second quadrant, so it is relatively independent, but it is very close to the border of the first quadrant. These three failure modes, FM2, FM5, and FM12, are causative and significant. Although FM11 failure mode is more influenced by other failure modes, its relations with other failure modes are significant. We estimate that the ERPN model will be successful and significantly reduce the monitored criteria. This is also indicated by the auxiliary criteria, as the given 4 failure modes influence the other 7 failure modes (with repetition) with a significant relation and influence 15 by the average intensity relation.  
The conventional PFMEA model has only one failure mode (FM9) in the first quadrant, FM12 in the second quadrant (close to the first), and two failure modes (FM8, FM11) only in the third, although both with higher significance (Figure 6). We refer to only two failure modes as causative, namely FM9 and FM12. We assume that this model will also reduce the monitored criteria, though as compared to the DEMATEL and ERPN models with a lower success rate. This is also indicated by auxiliary criteria regarding the number of affected failure modes with average and lower intensity.  
Figure 6: Main failure modes in PFMEA combined with ERPN and their relations with the other failure modes.  
In our case, the success of the models is determined by the relations of average and low intensity, but also by the distribution of failure modes in the quadrants of the digraph (Figure 2) of the DEMATEL model.