The School Bus Routing Problem (SBRP) covers the issue of establishing plans to efficiently transport students distributed across a designated area to the relevant schools using defined resources. As with the similar Vehicle Routing Problem (VRP), the SBRP may have diverse constraints such as heterogeneous vehicles, the allotted time window and multiple depots. Many solutions for effectively solving the problem are currently being studied. By their nature, these routing problems are NP-Hard (non-deterministic polynomial-time hard) problems in which the search domains increase exponentially as they become larger, thus making it difficult to obtain solutions using an exact approach except for relatively simple and localized problems. Therefore the heuristic approach is being studied in many regions. In this study, an algorithm was developed using genetic algorithms, which stem from meta-heuristic algorithms, and the algorithm was tested against diverse problems to identify its performance and practicality.

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Major ports worldwide suffered from various problems such as labor shortage, port congestion, and global supply chain disruptions during COVID-19. To ensure stable operations of ports in such scenarios, one option is to adopt fully automated terminals. This study aimed at evaluating the performance of fully automated terminals compared with that of non-fully automated ones during the disrupted logistics due to coronavirus. Four ports that simultaneously operate both fully and non-fully automated terminals were selected. The performance of the target terminals was measured based on quantitative factors: throughput, number of ship arrivals, and berthing time. The results showed that the fully automated container terminals present better operational performance than the non-fully automated terminals. The former achieved large increments in the throughput, small decreases in the berthing time per ship, and increases in the number of ship arrivals. Moreover, there were economic benefits, revealing that the total terminal profit at the fully automated terminals was significantly increased, whereas that at the non-fully automated ones decreased based on berthing times. Therefore, fully automated terminals can be considered as alternatives for responding flexibly and stably during crises such as COVID-19.

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