# Coal and Gas Outburst Risk Prediction and Management Based on WOA-ELM
## 5 Results and Discussion
### CBR Application Analysis  
A case matching analysis was performed using one piece of data, as shown in Table 12.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Case Name**} & \multicolumn{5}{c}{**Case Basic Information**} \\ \cline{2-7}  & **Gas Pressure** & \multicolumn{2}{c}{**Initial Velocity**} & \multirow{2}{*}{**Porosity**} & \multirow{2}{*}{**Coal Sturdiness**} & \multirow{2}{*}{**Gas Content**} & \multirow{2}{*}{**Evaluation of Prominent**} \\
**Number** & **(MPa)** & & & & & **Coal Seams** \\ \cline{3-7}  & 0.7 & 9 & 5.8 & 0.68 & 9.36 & 100\% \\ \hline \multirow{5}{*}{Regional risk forecast} & Comprehensive regional preventive measures & Testing the effectiveness of regional preventive measures & \multirow{5}{*}{Regional validation measures} & \multirow{5}{*}{Prediction of working face risks} & \multirow{5}{*}{Local preventive measures} \\ \cline{3-7}  & 100\% & 20\% & 10\% & 10\% & 10\% & 10\% \\ \cline{2-7}  & Local integrated control measures & Gas monitoring system & Mine ventilation system & Management of compressed air & Management of emergency evacuation & Personnel location system management \\ \cline{2-7}  & testing & management & management & self-help systems & systems & management \\ \hline \multirow{2}{*}{10\%} & 20\% & 80\% & 80\% & 80\% & 20\% \\ \cline{2-7}  & \begin{tabular}{c} Countermeasures \\ after the \\ occurrence of coal \\ and gas outburst \\ \end{tabular} & \begin{tabular}{c} Whether to \\ operate in \\ accordance with \\ safety regulations \\ \end{tabular} & \begin{tabular}{c} Safety protection \\ and personal \\ safety protection \\ are in line with \\ the requirements \\ \end{tabular} & \
\begin{tabular}{c} Are the \\ procedures or \\ plans or technical \\ measures \\ prepared as \\ required \\ \end{tabular} &
\begin{tabular}{c} Adequacy of \\ geological \\ structure or mine \\ pressure \\ monitoring or \\ studies \\ \end{tabular} & Gas outburst risk value \\ \hline \multirow{2}{*}{0} & \multirow{2}{*}{0} & \multirow{2}{*}{1} & \multirow{2}{*}{0} & \multirow{2}{*}{1} & \multirow{2}{*}{2} \\ \cline{3-7}  & & & & & \\ \end{tabular}
\end{table}
Table 12: Case matching analysis data.  
Figure 7: Predicted values of gas outburst risk from WOA-ELM model with different size pop.  
According to Equation (12), the similarity between the current gas outburst and all cases in the case base is calculated and set \(S_{y}\) = 0.9. According to Equation (13), cases with similarities up to \(S_{y}\) will be retrieved, and there are several cases with the highest similarity to the above data. Only one case is listed here, as shown in Table 13.  
The case is similar to the case \"151\" in case \"15\"; the similarity degree is 0.9024, and the risk level is 2. According to the status of similar cases, corresponding measures are proposed for the current prominent gas risks: It is in the low-risk stage with the possibility of rising medium risk. At this stage, check whether various indicators in the gas characteristics have exceeded the limit or are abnormal. If there are abnormalities, find out whether the system is sound, whether the responsibility is compacted, whether the extraction is up to standard, whether the ventilation system is reliable, whether the equipment maintenance is qualified and whether the site management is in place. Check whether the local comprehensive preventive measures are qualified, and do personal and complete safety protection before operations.