## 3 Results  
The application of the method is presented in an example. It is based on the schedule of a project to build a single block of flats (rainforced concrete frame filled with masonry, monolithic floor slabs--a structure typical for Polish housing). The network model (Figure 1) presents relationships between processes entrusted to specialized crews/subcontractors. The project scope is broken down into 14 processes plus two dummy nodes: project start and project finish. The process durations are defined as random values of triangular distribution, and their costs are deterministic. The values of costs were derived from a real-life cost plan, and the parameters of random variables of process durations were the construction superintendent's estimates gathered during an interview. Table 1 lists the values of process parameters. The predefined time for completion is \(T_{max}\) = 200 days. Figure 2 presents the baseline schedule. Processes marked black are the processes whose start days must be protected against disruption (so the processes that belong to the set \(V_{d}\)). The unit costs of their delays are set to 1% of their total value--for each day of delay (they can be understood as penalties agreed with the subcontractors hired to deliver them). These processes are to be started according to the _railway policy_. The unit cost of delaying the whole project is also 1% of the total project cost (the sum of costs shown in Table 1), so 270,045 EUR/day (delay penalty of the main contract). Figure 1: Project network (example). It was assumed that the project starts at moment zero (no delay). The \"Earthworks\" are to be carried out using the baseline methods (no time reduction measures--no options available). The same holds for the \"Tests on completion\". As for the remaining processes, each is assigned two options of time-reducing measures; their parameters are presented in separate tables (Tables 2 and 3) for clarity. The options with longer expected values of process durations are grouped in Table 2. Following the convention of numbering options in ascending order according to the scale of duration reduction (described in the previous chapter), this table presents the set of options with index \(j=1\). Table 3 groups options that compress durations more strongly, thus \(j=2\). Please note that stronger compression was assumed to be more costly (last column in Tables 2 and 3). \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{\(i\)} & \multirow{2}{*}{**Process Name**} & \multicolumn{2}{c}{**Minimal**} & \multicolumn{1}{c}{**Maximal**} & \multicolumn{1}{c}{**Mode**} & \multicolumn{1}{c}{**Expected**} & \multicolumn{1}{c}{**Cost**} \\  & & **Duration (Days)** & **Duration (Days)** & **(Days)** & **Value (Days)** & **(EUR)** \\ \cline{3-7}  & & \(t_{ai}\) & \(t_{bi}\) & \(t_{mi}\) & \(t_{i}\) & \(c_{i}\) \\ \hline
1 & Earthqu & 5 & 13 & 6 & 8 & 200,000 \\
2 & Frame & 33 & 48 & 39 & 40 & 24,000,000 \\
3 & Roof (structure) & 19 & 32 & 24 & 25 & 140,000 \\
4 & Roof (cladding) & 20 & 37 & 33 & 30 & 175,000 \\
5 & Facade & 42 & 62 & 49 & 51 & 165,000 \\
6 & External works & 39 & 49 & 44 & 44 & 125,000 \\
7 & Partitions & 19 & 32 & 24 & 25 & 340,000 \\
8 & Systems & 20 & 26 & 32 & 26 & 600,000 \\
9 & Plastering & 14 & 27 & 22 & 21 & 170,000 \\
10 & Screeds & 21 & 35 & 28 & 28 & 320,000 \\
11 & Decoration & 21 & 31 & 26 & 26 & 230,000 \\
12 & Floors & 16 & 26 & 18 & 20 & 80,000 \\
13 & Joinery & 26 & 33 & 28 & 29 & 500,000 \\
14 & Tests on completion & 1 & 1 & 1 & 1 & 0 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: List of processes and their parameters. Figure 2: Baseline schedule (example). The simulation model was coded using GPSS language, and the simulations were conducted in GPSS Word Minuteman Software. The experiment was repeated with different lags (\(\lambda\)) for introducing the time compression measures. Each experiment involved 10,000 simulation runs. Table 4 lists the expected values of delayed start dates of processes, juxtaposing three cases.