# Application of Collision Warning Algorithm Alarm in Fishing Vessel's Waterway
## 3 Application of Collision Warning Algorithm to Real Ship Test
### Results of the Real Ship Test
Scenario 2  
In scenario 2, all three ships navigated toward a single location for approximately five min, and the analysis results are shown in Figure 6 and Table 4. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Time (s)** & **Own Ship** & **Target Ship** & **Distance (m)** & **DCPA (m)** & **TCPA (s)** & **Risk** & **Alarm** \\ \hline
99.3 & Ship C & Ship B & 1689.56 & 21.86 & 148.87 & 7.0 & first Main \\
105.1 & Ship A & Ship C & 1596.54 & 31.17 & 140.82 & 7.0 & first Main \\
161.1 & Ship C & Ship B & 924.29 & 10.50 & 83.54 & 7.0 & second \\  & & & & & & Main \\
211.5 & Ship A & Ship B & 89.41 & 27.55 & 146.34 & 7.0 & Main \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Analysis of the situation when the first alarm was generated on each ship from the test results of Scenario 1. As shown in Figure 6a and Table 4, ships B and C encountered each other at 176.4 s after the test started to satisfy the DCPA and TCPA criteria and the first main alarm was generated for the first time. Then, it was continuously generated owing to the risk value. At 191.6 s, the first main alarm was generated on ship A as well owing to the encounter between ships A and B indicating that it was generated on all three ships. At 210.9 s, ships A and B came close to each other such that the alarm stage was changed to the second main alarm in both ships. At 224.5 s, ship C also met the distance criteria and the second main alarm was generated. As shown in Figure 6b, when the developed algorithm along with DCPA and TCPA criteria were applied, the first main alarm was generated at 176.4 s. However, the alarm went on and off repeatedly under only DCPA and TPCA criteria because of the course-keeping performance of small fishing vessels. Furthermore, for \(\sim\)28 s (from 252.0 to 280.0 s) despite the close distance that caused risky situations, the DCPA and TCPA criteria were not met and an alarm was not generated. As in scenario 1, step-by-step alarms were generated continuously only under the PARK model risk value criterion. However, pre-alarm was generated despite sufficient time for the encounter. Hence, the algorithm developed in this study helps the operator to acknowledge the danger by displaying a relatively continuous \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Time (s)** & **Own Ship** & **Target Ship** & **Distance (m)** & **DCPA (m)** & **TCPA (s)** & **Risk** & **Alarm** \\ \hline
176.4 & Ship C & Ship B & 1387.23 & 6.70 & 149.93 & 7.0 & First Main \\
191.6 & Ship A & Ship B & 1049.63 & 12.43 & 149.77 & 7.0 & First Main \\
210.9 & Ship B & Ship A & 913.81 & 29.53 & 139.56 & 7.0 & Second \\  & & & & & & Main \\
224.5 & Ship C & Ship B & 925.76 & 1.08 & 100.51 & 7.0 & Main \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Analysis of the situation when the first alarm was generated on each ship from the test results of scenario 2. Figure 6: (**a**) Diagrammatic representation of the track of alarms generated from the test results of scenario 2 and (**b**) graphical representation of the alarms generated on ship C depending on the time (from the top, alarms based only on DCPA and TCPA criteria, alarms based only on PARK model risk value criterion, and the alarms based on the algorithm). alarm signal in a dangerous situation without disturbing the operator with frequent alarms at longer distances.