## 5 Example Analysis  
Taking an urban area in Hebei Province, China as an example, the season is set in the spring, the RA can be constructed through the reasonable selection of DERs. According to the distribution of the urban road network, the urban area is divided into 18 regions, as shown in Figure 2.  
The types of DERs in each region are different. \(X_{n}^{DG}\), \(X_{n}^{ES}\) and \(X_{n}^{DR}\) represent the existence of DG, ES and DR in the \(n\)-th region respectively, 1 is the existence and 0 is the non-existence. The types of DERs in 18 regions are shown in Table 1.  
Figure 1: The flow chart of FMD-CBA. Figure 2: Location and number of each area. In Table 1, the DG in regions 1 and 13 are WP, and the DG in other regions is PV. In DG, the generation characteristics of WP and PV are mainly considered. In ES, the power characteristics of electric vehicle are mainly considered. In DR, response characteristics of demand resource are mainly considered, which can also be regarded as virtual output characteristics. As can be seen from Table 1, there are 17 regions with DG, of which 15 regions are WP and 2 regions are PV. In the process of multi-scenario construction, according to the 92-day WP and PV output curves in the 17 regions in spring, the feature indexes are extracted, and 92 clustering vectors containing the output characteristics of each region are obtained, of which the dimensions of the vector are 68. The improved K-means algorithm is used to cluster 92 eigenvectors in spring. The relationship between the number of clusters and the contour coefficients is shown in Figure 3.  
The number of clusters is set to 2-9. By calculating the contour coefficients corresponding to the number of different clusters, the optimal cluster number is 4 and the maximum contour coefficient is 0.74. The number 1-92 are used to represent the 1-92 th days of spring. The ratio of the number of days in each scenario and the total number of days represents the probability of the scenario. The probability and the corresponding days are shown in Table 2. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c c c} \hline \hline
**Number** & **1** & **2** & **3** & **4** & **5** & **6** & **7** & **8** & **9** & **10** & **11** & **12** & **13** & **14** & **15** & **16** & **17** & **18** \\ \hline DG & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 1 & 0 & 1 & 1 & 1 \\ ES & 0 & 1 & 1 & 1 & 0 & 1 & 1 & 0 & 0 & 1 & 1 & 1 & 0 & 1 & 0 & 0 & 1 & 1 \\ DR & 0 & 1 & 1 & 1 & 1 & 1 & 1 & 0 & 0 & 1 & 0 & 1 & 0 & 1 & 0 & 1 & 1 & 1 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Distribution of resources in each region. Figure 3: The curve of cluster number and contour coefficient. Taking the WP in the 1 st region and the PV in the 4 th region as an example, the typical output curve and daily output curves in each scenario are plotted. The typical output value at each time is expressed by the average output value of all days, as shown in Figures 4 and 5. By comparing the typical output curves in the four scenarios, it can be seen that the curves are significantly different. The typical output of WP decreases as a whole, and the typical output of PV increases as a whole. This trend is in line with the trend of wind speed decreasing and solar irradiance increasing gradually from the beginning of spring to the end of spring. The parameters of FMD-CBA are set as follows: the size of the bat population is 60, the number of iterations is 100, and the initial emission rate is 0. In order to verify the effectiveness of the algorithm, the bat algorithm (BA) and ant colony algorithm (ACA) are added to compare the optimal results with CBA, and the numbers of populations and iterations are same. The convergence curves of the three algorithms are shown in Figure 6. In the early stage of iteration, the convergence characteristics of the three algorithms are basically the same. However, with the increase of iteration times, the number of Pareto solution sets searched by CBA is obviously more than that of the other two algorithms.