## 4 Description of the Developed Software
### Methodology for the Estimation of Unknown Input Structural Parameters  
As mentioned in Section 4.3, the input vectors of the MFPNN used are formed utilizing the external function \"FORM_ANN_INPUT\" (Table 5). Moreover, as stated in Section 3 (Equation (2)), the input vectors of the MFPNNs embedded in the current version of the software application include 14 seismic (Table 2) and four structural parameters (Equation (2)). The seismic parameters are estimated by the processing of the input records (accelerograms) that could be obtained from freely available databases (e.g., PEER strong motion database [48]) or in real-time (immediately after an earthquake event) by the stakeholders of accelerometric stations using well-documented formulas [39, 40]. These formulas are inserted in the external function \"SEISMIC_PARS\" (Table 5). \begin{table}
\begin{tabular}{l l} \hline \hline
**Function/[GUI Component—Panel]** & **Procedure** \\ \hline SavNRun\_Callback/[”SAVE \& NEW RUN”—Panel 4], & Calls the external function “FINAL\_OUTPUT” that creates the output file which includes all input data and results. \\ (Figure 10) & \(\bullet\) & Clears the memory (external function “CLEAR\_MEM”) and restarts the application. \\ \hline \hline \end{tabular}
\end{table} 
Table 4: _Cont._ \begin{table}
\begin{tabular}{l l} \hline \hline
**Function/[Called from Callback Function]** & **Procedure** \\ \hline “SEISMIC\_PARS”/SePar\_Callback & \begin{tabular}{l} Calculates the seismic parameters of the selected excitation in directions 1 and 2. \\ \end{tabular} \\ \hline “GR\_CODE\_EL\_SPECTR”/StrPar\_Callback & \begin{tabular}{l} Calculates the design elastic acceleration spectrum (according to the valid seismic codes at the year of the building’s design). \\ \end{tabular} \\ \hline “FORM\_ANN\_INPUT”/Results\_Callback & \begin{tabular}{l} Configuration of the vectors used as input of the selected \\ trained ANNs. \\ \end{tabular} \\ \hline “TRAINED\_ANN\_SELECTR”/Results\_Callback & \begin{tabular}{l} Creates and activates a window with GUI tools for the selection \\ and insertion of a trained ANN (Figure 11). \\ \end{tabular} \\ \hline “ANN\_CALCS”/Results\_Callback & \begin{tabular}{l} Simulates the imported ANN for the rapid prediction of the DS \\ of building. \\ \end{tabular} \\ \hline “FSRVS\_CALCS”/Results\_Callback & \begin{tabular}{l} Required calculations for the rating of building and its \\ classification into the priority classes, defined in the framework \\ of FSRVS method. \\ \end{tabular} \\ \hline “FINAL\_OUTPUT”/SavEx\_Callback and SavNRun\_Callback & \
\begin{tabular}{l} (a) Creates and activates a window for the saving of the final \\ output file. \\ (b) Creates the output file that includes all input data and \\ (intermediate, final) results. \\ \end{tabular} \\ \hline “CLEAR\_MEM”/SavEx\_Callback and SavNRun\_Callback &
\begin{tabular}{l} Clears the memory from the parameters that are defined during \\ the running of the application. \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Description of the external functions of the software. On the contrary, the structural parameters required as input are, in general, difficult to estimate instantly since they are not limited to geometrical parameters (such as the total height of buildings Htot, Figure 14) that could be easily measured or defined during RVI. Figure 13: Brief flow chart of the source code of the developed software application. Input parameters such as the base shear ratio that is received by RC walls (if they exist) along the two principal directions (ratios n\({}_{\text{v1}}\) and n\({}_{\text{v2}}\)) and the structural eccentricity e\({}_{0}\) require time-consuming calculations (not compatible with the RVI methods) in order to be defined. As already mentioned in Section 3, the software application proposed herein can be implemented for the seismic damage assessment of RC buildings independently of reliable data availability.