## 5 Case Study and Discussion  
In addition to introducing the application and proper verification, the efficient and full performance of this tool is explained briefly through a case study. The main objective of this section is to discuss the results of the case study. To achieve the objective, an investigation is conducted on models of seismic sources in South Korea and it is made from a historical and instrumental earthquake catalog from [PERSON] et al. [55]. The Gunnam concrete gravity dam in South Korea is selected as the site by taking the latitude and longitude value (38.104\({}^{\circ}\) N and 127.021\({}^{\circ}\) E). The site-specific magnitude is appropriate for use in seismic risk assessment because there are only a few strong GM data and seismological information for the dam sites in South Korea. Table 4 displays the range of magnitude as well as the seismicity parameters corresponding to \"Source ID\" of the seismic source models. For the magnitude-frequency relationship, Gutenberg-Richter relation [38] is considered for each area source. Table 5 presents the value of latitude and longitude for each seismic source of the corresponding selected source model (here taken M-B seismic model in South Korea) [56]. Among several earthquake records, this seismic source model (M-B) recorded two major sources, which are identified here as RS1 and RS2 in Figure 16[57]. After operating with the input data as the maximum and minimum values of magnitude from Table 4, Figure 17 explains the 10 segmental views of area source, distribution of source-to-site distance and magnitude and single-source hazard curve for RS1. Similarly, Figure 18 shows the illustration for RS2. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Source Model**} & \multirow{2}{*}{**Source ID**} & \multirow{2}{*}{**Maximum Magnitude**} & \multirow{2}{*}{**Minimum Magnitude**} & \multicolumn{2}{c}{**Seismicity Parameters**} \\ \cline{5-5}  & & & & **a** & **b** \\ \hline M-B & RS1 & 6.7 & 3.0 & 2.93 & 0.76 \\  & RS2 & 6.5 & 3.0 & 2.53 & 0.75 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Seismicity parameters. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Source Model**} & \multirow{2}{*}{**Source ID**} & \multirow{2}{*}{**Latitude**} & \multirow{2}{*}{**Longitude**} \\ \cline{5-5}  & & 1 & 38.60\({}^{\circ}\) N & 129.40\({}^{\circ}\) E \\  & & 2 & 37.13\({}^{\circ}\) N & 127.60\({}^{\circ}\) E \\ RS1 & 3 & 35.20\({}^{\circ}\) N & 125.80\({}^{\circ}\) E \\  & 4 & 33.00\({}^{\circ}\) N &  
Figure 16: Seismic source model for probabilistic seismic hazard analysis of South Korea showing the affected area of earthquakes produced by accounting more than 1800 historical earthquakes records. The boxes indicate the source identification; the transparent portions show the boundary of the affected area and the dam icon focuses on the site location on the map. Figure 17: (**a**) Segmental view of area source, (**b**) Probability density function of distance, (**c**) Illustration of probability density function for magnitude for a source with a truncated Gutenberg–Richter distribution, (**d**) Probabilistic seismic hazard curve, respectively for RS1. Figures 17b and 18b show the characterization of source-to-site distance from the RS1 and RS2 to the Gunnam dam. The site was near about the source RS2 and far from the RS1, as a result, the average 283 km showing a 0.80 for the probability of occurrence. Except for this, the probability distributions for the distance between 28.7 and 555.47 km varies approximately from 0.024 to 0.160 (Figures 17b and 18b). Analyzing Figure 17c, the increasing pattern has been shown in the exponential of the probability distribution, which is found 0,01 at the magnitude of 6.38 to 0.38 at a magnitude of 4.12 for RS1. Similarly from Figure 18c, the increased value is found from 0.02 at the magnitude of 6.38 to 0.35 at a magnitude of 4.12.