## 2 Problem Statement
### Yangtze River Port  
Figure 1 shows the target port, which comprises two basins. Both basins connect to the navigation channel, and the two basins are 200 m apart. Each basin contains eight berths, with the distance between each berth and the basin entrance varying. The berths can be divided into three types: (1) berths for barges, (2) berths for seagoing ships, and (3) berths for all types of ships.  
Large coastal ports often adopt a \"first come, first served\" scheduling principle to serve ships. Ship entry operations require cooperation among the port, shipping agencies, and inspection departments (including customs, maritime, and inspection and quarantine). Operationally, arriving barges can be directly arranged and dispatched by the port without any declaration, whereas seagoing ships generally need to be declared by a shipping agent seven days before entering the port. Figure 2 shows the specific processes involved in entering the target port for seagoing ships. Customs receives and reviews orders two to three days before a ship enters the port, and provides cargo notification upon arrival. The port will arrange for the ship to berth, and the inspection department will perform risk assessment based on the type of cargo, current policies, ship credit, historical control frequency, and other necessary factors. The inspection department decides whether to perform further inspection on this ship according to the assessed results. If the risk parameter exceeds a given threshold, this ship is required to lift its goods to the inspection area to check whether they match the manifest. If the nature of goods cannot be determined,  
Figure 1: A port example in Yangtze River Basin.  
inspection personnel also take samples and send them to a specialized organization for testing. This process requires both time and cost, and the selected ships can only operate after they have passed the inspection. Furthermore, when all paperwork is completed, the ship must also be inspected and approved before it can be released to leave the port.  
Clearly, ship scheduling represents a system engineering problem involving multiple parties. The port necessarily employs a more intelligent and compact ship scheduling strategy, which can not only reduce labor costs and shore bridge resource (e.g., cranes and trucks) wastage, but also improve port throughput. Furthermore, the inspection department also requires a scheduling strategy that can help to allocate inspection tasks, rationalize work intensity, improve work efficiency, and reflect more humane work characteristics. Finally, shipping companies expect to receive timely port services, complete the loading and unloading of their goods efficiently, minimize waiting time costs, and accelerate ship turnover [14]. These various expectations necessitate that any scheduling problem be based on the actual conditions of the port. It must propose a coordinated scheduling strategy for waterways and berths that considers the interests of all three parties and their multiple objectives. The strategy should aim to complete ship inspections within the specified time frame, reduce berth deviation costs, shorten the total scheduling time for all ships, and improve berth utilization.