## 3 Results
### Verification of Proposed Algorithms with Real-World Data  
The measurements obtained throughout the factory are tabulated and represented in a sound-level map, as illustrated in Figure 11. Notably, the sound levels are significantly higher in the lower section of the factory compared to other areas, attributable to the facility operating at only 50% of its capacity, with only one production line. Subsequently, the positions of the sound sources are identified, and their respective Sound Pressure Levels (SPLs) are measured. These locations are documented based on estimated distances from the nearest walls to facilitate accurate plotting on the floor plan. The sound sources are associated with specific workstations, which collectively encompass a substantial area; consequently, the SPL is recorded at the midpoint of each workstation area. Measurements  
\begin{table}
\begin{tabular}{c c c c} \hline
**Sound Source** & **Distance, r (m)** & **SPL (dB)** & **SPL at Receiver (dB)** \\ \hline
1 & 14.14 & 59.0 & 36.0 \\
2 & 14.14 & 49.0 & 26.0 \\ \hline \end{tabular}
\end{table}
Table 2: Manually calculated SPLs.  
Figure 10: Three-dimensional version of ray diagram during simulation verification (with reflection).  
\begin{table}
\begin{tabular}{c c} \hline
**Method** & **Resultant SPL (dB)** \\ \hline Manual Calculation & 36.41 \\ MATLAB Algorithm (no reflection) & 36.41 \\ MATLAB Algorithm (with reflection) & 38.1 \\ \hline \end{tabular}
\end{table}
Table 3: Comparison between the algorithm and manual calculation.  
are conducted at a height of 2 m from the ground to ensure consistency. The locations and SPLs of the sound sources are summarised in Table 4.  
The scenario is simulated using the developed algorithm by utilising the source data presented in Table 4 and the factory's floor plan. The resulting simulated Sound Pressure Levels (SPLs) are plotted on a grid and represented on a sound level map, as illustrated in Figure 12. Given that only one side of the factory was operational during measurements, this is depicted in the sound level map. A comparative analysis of both datasets focuses on the differences in dB values and the percentage differences. Figure 13 presents a line graph illustrating a comparison between the SPLs measured on site and those obtained from the simulation. The graph demonstrates that the simulation closely follows the trend of the real-world data, validating the algorithm's functionality.  
The average difference between the simulated and measured SPLs is noted to be 3.06 dB, with the simulation indicating higher values than those recorded in the field. This discrepancy is attributed to the lack of consideration for environmental openings, such as windows and doors, in the simulation model. To enhance accuracy, future model iterations should incorporate a more detailed floor plan that includes the specific locations of machines and openings in the environment.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Locations (Noise Source)** & **x** & **y** & **z** & **Max SPL (dB)** & **Dosage (\%)** \\ \hline A & Sanding station & 33 & 1 & 2 & 80.6 & 80 \\ B & Spraying station & 5 & 15 & 2 & 75.2 & 100 \\ C & Auto disc station & 15 & 1 & 2 & 74.0 & 50 \\ \hline \hline \end{tabular}
\end{table}
Table 4: Sound sources at the site with their SPLs and location (Cartesian coordinate).  
Figure 11: Recorded SPLs from collected real-world data in dB.  
Figure 12: Simulated SPLs plotted on a grid and heatmap in dB.