# Operation Optimization of the Sea Container Fleet Based on the Double-Level Planning Model
## 3 Simulation Analysis and Verification  
### Example Analysis  
Based on reference [20], the mathematical model is simulated using Matlab 2023 software. This paper selects three Asia-Europe routes operated by a certain company to find the optimal route allocation and speed plan. The specific port call sequence is shown in Table 2. The corresponding freight demand and relevant parameters of ships for each segment of the three routes are shown in Tables 3 and 4. Given that the berthing duration of all ports is two days, and the prices of heavy fuel oil and gasoline are USD 350/ton and USD 650/ton, respectively, the ship allocation plans for the routes shown in Table 5 can be obtained under the assumption of ignoring the actual restrictions on the freight volume of each route segment. From Table 5, it is evident that while scheme d can minimize the overall operation cost of the ships, the third ship type with a capacity of 6500 TEU, as mentioned in Table 3, falls short of meeting the maximum freight demand of 7957 TEU on route 2. Hence, this scheme is not feasible. Similarly, in scheme a, the second ship type with a capacity of 7000 TEU cannot cater to the transportation requirements on route 2. Moreover, both scheme c and scheme e encounter the same problem. Among the feasible options, scheme b totals an operation cost of USD 13.857 million, while scheme f amounts to US 13.818 million. Both schemes incur a carbon tax of USD 179,000, indicating identical carbon emissions. Consequently, scheme f is identified as the optimal ship allocation scheme. In scheme f, route 1 is equipped with 11 type 2 ships with a container capacity of 7000 TEU and the best speed of 17.7 knots; route 2 is equipped with 10 type 1 ships with a container capacity of 8000 TEU and the best-expected speed of 17.6 knots; route 3 is equipped with 10 type 3 ships with a container capacity of no less than 6500 TEU and the best speed of about 18.3 knots. Compared with scheme b, scheme f saves USD 39,000 in total weekly operating costs, reflecting the economic benefits of speed and route allocation. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Ship Type**} & **Container** & **Weekly** & **Fuel** & **Weekly Diesel Fuel** & **Minimum** & **Maximum** \\  & **Capacity THU** & **Operating** & **Costs** & **Consumption** & **Consumption/t** & **Speed/kn** & **Speed/kn** \\ \hline
1 & 8000 & 332,000 & 0.0068 & 82 & 15 & 28 \\
2 & 9500 & 345,000 & 0.0072 & 85 & 14 & 27 \\
3 & 7000 & 310,000 & 0.0065 & 80 & 16 & 30 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Vessel parameters. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Shipping Route** & **Total Torque** & \multicolumn{6}{c}{**Port of Call**} \\ \hline
1 & 21,036 &
\begin{tabular}{c} Hong Kong \(\rightarrow\) Xiamen \(\rightarrow\) Kaohsiung \(\rightarrow\) Yantian \(\rightarrow\) \\ Singapore \(\rightarrow\) Rotterdam \(\rightarrow\) Hamburg \(\rightarrow\) Felixstowe \(\rightarrow\) \\ Antwerp \(\rightarrow\) Singapore \(\rightarrow\) Hong Kong \\ Yantian \(\rightarrow\) Hong Kong \\ 2 & 23,281 & \(\rightarrow\) Ningbo \(\rightarrow\) Singapore \(\rightarrow\) Rotterdam \(\rightarrow\) Felixstowe \(\rightarrow\) \\ Hamburg \(\rightarrow\) Antwerp \(\rightarrow\) Yantian \\ Yantian \(\rightarrow\) Kaohsiung \(\rightarrow\) Ningbo \(\rightarrow\) Shanghai \(\rightarrow\) Hong \\ Xong \(\rightarrow\) Singapore \(\rightarrow\) Rotterdam \(\rightarrow\) Hamburg \(\rightarrow\) \\ Antwerp \(\rightarrow\) Singapore \(\rightarrow\) Yantian \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Distance of routes in order of port calls.