3.2. Analysis of Virtualized Port-Container Terminal
As previously mentioned, this study aims to analyze the operation of the container terminal by establishing a cloud-based virtualized port-container terminal. A simulation model for quay performance analysis is developed as in
Figure 2 to determine the performance of this container terminal. This model is based on actual data collected from domestic container terminals, including vessel arrival time distribution, number of assigned quay cranes and crane productivity.
This simulation model is period-oriented, that is, the system is simulated in constant time intervals (the so-called period length). All activities occurring in the real system in a given interval are correspondingly represented in the model, as shown in
Figure 3.
In this model, the total area of the port-container terminal is around 1,152,500 m
2 and includes five berths; the total length of the inner wall for each berth is 1200 m, with a depth of 16 m. The container unit site has a capacity of around 780,000 TEUs and the freezer unit can store around 1400 TEUs.
Figure 4 shows the implemented virtual port-container terminal, which is based on the actual Busan port “A” container terminal. The virtualized port-container terminal consists of a quay, quay crane area, container yard, gate and transfer crane, with a total of 20 blocks.
The implemented virtualized port-container terminal sets the quay crane and the dock location of the vessel according to the mariner. The yard crane is installed and set up in the container equipment cabinet by dividing the containers for import, export, dangerous goods, freezer and empty boxes. Additionally, the path of the operational process for the physical equipment was set from the gate to the yard tractor. The assumptions in this study are that the equipment does not fail during the simulation run time and the ship’s landing time is defined in advance, meaning it cannot be changed. Additionally, the number of equipment deployed per vessel is assumed to be constant.
We constructed a container terminal for a virtual port and conducted 10 simulations per year. The computer specifications for building and analyzing the container terminal of the virtual port are OS: Windows 10, Processor: Intel (R) Core (TM) i7-6700 CPU@3.40 GHz, RAM: 8.00 GB, 64-bit system [
16].
Table 3 shows the operational results of the reach stacker equipment in the virtualized port-container terminal. Currently, there are eight units of equipment, but the simulation results show that only four units are operational, with a throughput of 1137 TEUs. Therefore, it is more efficient to operate four units of equipment instead of eight at the actual port-container terminal, and the remaining four units can be used as alternatives in case of a failure of the existing reach stacker. Further, no new equipment needs to be introduced. The container throughput is 284 TEUs per reach stacker and 2.37 TEUs/h. The average operating distance per piece of equipment is 43.33 km. The average waiting time at the port-container terminal is 2 h and 14 min, and the working time is 11 h and 29 min.
Table 4 shows the operational results of the forklift equipment operating at the virtualized port-container terminal. Among the nine forklifts, the ninth is not operational. Therefore, it is used as an alternative in case of existing equipment failure. Additionally, the average container throughput for the nine forklifts is 271.44 TEUs, the moving distance is 11.94 km, and the working time of the forklift equipment is 8 h and 29 min. However, the waiting time is 10 h and 29 min. This shows that the waiting time at the port-container terminal is higher than the entire working time of the forklift equipment. Further, the working hours of the eighth forklift are reduced markedly, indicating the actual forklift equipment can be operated with only seven units.
Appendix A shows the operational results of the yard crane equipment operating in the port-container terminal. The average throughput of all yard crane equipment is 355.63 TEUs, and the hourly throughput handled by each container is 2.96 TEUs. The distance traveled from the port-container terminal is 20.07 km, and the average working time is 17 h and 25 min. The average number of containers reprocessed in the unit site is 39.44 TEUs. Of the 41 yard cranes, only 38 are operational; therefore, three of the yard cranes are not used. The number of containers reprocessed at the unit site is 39.44 TEUs, and this work is mainly handled by cranes 13 to 24. This indicates that the containers are being reprocessed at the port-container terminal unit where the corresponding yard crane equipment is placed.
Table 5 shows the operational results of the quay crane equipment operating at the virtualized port-container terminal. The average processed container throughput is 3037.13 TEUs, each handling around 12.95 TEUs/h. The working time is 22 h and 30 min and the waiting duration is 29 h and 30 min, indicating that all quay crane equipment are operational. Therefore, there was no idle equipment. Operating equipment costs are also calculated. The government intends to calculate the reduction in operating costs due to the increased operational efficiency of the port-container terminal. The average operating cost per quay crane unit is USD 209,286. The operating cost of the quay crane equipment includes fixed and operating costs.
The correlation between the total container throughput and total operating costs shows that the higher the total container throughput is, the higher the total operating costs are, as shown in
Figure 5. However, when handling a certain level of container throughput (2000–3500 TEUs), the total operating costs are constant because the quay crane is large. Unlike the previously presented equipment, ongoing fixed costs are applied continuously.
According to the analysis, only four of the reach stackers are operated without problems. Eight of the nine forklifts, 38 of the 41 yardcranes, and 15 of the quay cranes were found to be handling containers in each port-container terminal smoothly. Therefore, as shown in
Table 6, the current relocation of operational equipment can reduce the operating costs of the port-container terminal by USD 13,870,000, with a reduction of USD 146,000 for the forklift, USD 584,000 for the reach stacker and USD 13,140,000 for the yard crane.