## 4 Materials and Methods
### Scheduling Procedure
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Time**} & **Eligible** & \multirow{2}{*}{**R1 = 7**} & \multirow{2}{*}{**R2 = 7**} & \multirow{2}{*}{**R3 = 10**} & **Duration** & \multirow{2}{*}{**LAD**} & **Decision** & **Full Time** & **Substitution** \\  & **Activity** & & & & & & & **Rule** \\ \hline \multirow{4}{*}{8.6} & I & 3 & 2 & 1 & 4.32 & - & C & 10.03 & \multirow{4}{*}{} \\  & E & 2 & 1 & 0 & 3.32 & - & C & 11.17 & \multirow{4}{*}{} \\  & D & 1 & 0 & 0 & 1.93 & - & C & 9.51 & \\  & H & 4 & 4 & 4 & 6.65 & 6.65 & D & - & \\ \hline \multirow{4}{*}{9.51} & I & 3 & 2 & 1 & 4.32 & 4.32 & C & 10.03 & \multirow{4}{*}{} \\  & E & 2 & 1 & 0 & 3.32 & - & C & 11.17 & \multirow{4}{*}{} \\  & H & \(4-2\) & 4 & \(4+4\) & 6.65 & 6.65 & S & 16.16 & \multirow{4}{*}{} \\  & G & 3 & 1 & 2 & 3.28 & 3.28 & D & - & 2R3 = 1R1 \\ \hline \multirow{4}{*}{10.03} & E & 2 & 1 & 0 & 3.32 & - & C & 11.17 & \multirow{4}{*}{} \\  & H & 4 & 4 & 4 & 6.65 & - & C & 16.16 & \multirow{4}{*}{} \\  & G & \(3-2\) & 1 & 2 + 4 & 3.28 & 3.28 & S & 13.31 & 2R3 = 1R1 \\ \hline \multirow{4}{*}{11.17} & H & 4 & 4 & 4 & 6.65 & - & C & 16.16 & \multirow{4}{*}{} \\  & G & 3 & 1 & 2 & 3.28 & - & C & 13.31 & \\ \hline
13.31 & H & 4 & 4 & 4 & 6.65 & - & C & 16.16 & \multirow{4}{*}{} \\  & J & 1 & 4 & 5 & 3.33 & 3.33 & S & 19.49 & \\ \hline \end{tabular} Legend: R1–R3 = resources, S = start; C = continue and D = delay, LAD = longest activity duration.  
\end{table} 
Table 5: _Cont._  
Then, the SMSRS model results were validated through a comparison with results obtained from single-skilled resource scheduling (SSRS) software (RESCON) and the existing deterministic MSRS model. RESCON is a resource-constrained scheduling educational software based on a single-skilled resource strategy. Table 8 shows the schedule summary results of the three projects based on SSRS software, MSRS, and SMSRS models. Next, the project delay and percentage delay for the projects were computed using Equation (3). The results are shown in Table 9; Table 10 with the summary depicted in Figure 5. Finally, the average percentage delay error for the three projects was computed as 10.50%. \[\%D_{i}=\frac{P_{i}-P_{B}}{P_{B}}\times 100\% \tag{3}\]  
where \(\%D_{i}\) is the percentage delay of schedule \(i\); \(P_{i}\) is the project duration for schedule \(i\) and \(P_{B}\) is the baseline project duration i.e., deterministic project duration. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Activity**} & \multirow{2}{*}{**Predecessors**} & \multirow{2}{*}{**Duration (Days)**} & \multicolumn{5}{c}{**Daily Resource Requirements**} \\ \cline{3-8}  & & & **R1** & **R2** & **R3** & **R4** & **R5** \\ \hline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hline \multicolumn{8}{c}{Daily resource availability} & 7 & 12 & 12 & 16 & 9 \\ \hline \hline \end{tabular} Substitution rule: 2R2 = 1R5, 2R2 = 1R1, 3R3 = 1R1 and 2R4 = 1R3.  
\end{table} 
Table 7: Project information for Project C.  
Figure 4: Network Diagram for Project C.