## 2 Literature Review
### Impact of Regulatory Policies and External Disruptions  
Regulatory policies profoundly influence container liner shipping by imposing constraints that reshape routing, fleet deployment, and demand acceptance strategies, compelling operators to balance compliance with cost efficiency. Environmental regulations, such as sulfur emission caps and carbon reduction targets, promote sustainable practices. [PERSON] and [PERSON] demonstrate through speed optimization models how minimizing fuel costs and emissions via measures like low sulfur fuel or speed reductions can increase operational costs by up to 20% [34]. [PERSON] et al. optimize tactical planning using a model that incorporates carbon taxes and varied ship efficiencies, achieving considerable emission reductions alongside cost minimization [27]. [PERSON] et al. propose a model for green liner shipping that balances costs and emissions through fleet deployment and fuel bunkering, resulting in significant emission reductions [28]. Trade policies, such as proposed U.S. surcharges on certain foreign built ships involving substantial fees per port call, necessitate rerouting or fleet reconfiguration [3]. [PERSON] et al. use regression-based econometric analysis to show that foreign investment restrictions raise shipping costs by 24-50% and reduce trade flows, necessitating adaptive routing models [35]. [PERSON] et al. and [PERSON] et al. apply descriptive statistics and network modeling to highlight how U.S.-China trade tensions increase operating costs by 5-10% and transit times by up to 12% on Asia-North America routes [36]. Safety regulations, for instance the International Ship and Port Facility Security Code, extend port turnaround times by 10-20%, indirectly increasing costs, as [PERSON]'s qualitative analysis indicates [37]. These studies underscore the need for optimization models that incorporate specific regulatory constraints.  
External disruptions, including pandemics, geopolitical events, and natural disasters, exacerbate operational challenges in liner shipping, requiring resilient strategies to mitigate delays and costs. The COVID-19 pandemic, as [PERSON] et al. show through AIS-driven data analysis, reduced China's port network connectivity by 15% due to congestion, while [PERSON]'s descriptive analysis reports a 20% rise in schedule disruptions, prompting network reconfiguration [38]. [PERSON] et al. propose a simulation-based optimization model, integrating simulation and optimization techniques to manage pandemic induced congestion, reducing delays and costs by up to 25% through optimized ship assignments [39]. [PERSON] et al. develop exact branch and bound and metaheuristic algorithms to optimize vessel deployment and routing under congestion, achieving 8-12% cost savings [40]. The 2021 Suez Canal blockage, which caused substantial daily trade losses according to [PERSON] et al.'s economic modeling, necessitated rerouting via the Cape of Good Hope, increasing transit times by 10-14 days [41]. [PERSON] et al. advocate port skipping, which their review shows can reduce delays by up to 20% [42]. Natural disasters, addressed by [PERSON] et al.'s distributed predictive control model, require rapid rerouting to minimize response times [43].