International Journal of Shipping and Transport Logistics (11 papers in press)

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• Open Access

  The impacts of relocating screening scanners on efficiency of transshipment container ports: policy implications for the maritime industry ( Free Full-text Access )

  by Jungyong Seo, Keyju Lee, Young-Joon Seo, A-Rom Kim 
  Abstract: With the recent rise in the importance of logistics security around the world, it is worth considering relocating container inspection systems (CISs) to make port operations more efficient. This study aims to investigate changes in the terminal process when container screening equipment is additionally introduced in an automated container terminal. This research conducts a series of simulation experiments to compare two location alternatives of container scanners regarding terminal efficiency. When container screening is hardened, it is found that relocating the CIS to the TP on the waterside of the yard block to perform container screening effectively improves terminal efficiency. Although the expenses in screening containers to the USA and the time required to handle the containers may increase because of complete container inspection regulations, our research suggests this may not be an insurmountable issue.
  Keywords: container screening; container scanner relocation; port efficiency; transshipment; simulation; Korean ports; container inspection systems; CISs.
  DOI: 10.1504/IJSTL.2025.10072345
   
  
• The spatial dependence of container throughputs and liner shipping connectivity in coastal countries prior to the COVID-19 pandemic  
  by Pei-Chun Lin, T.C.Edwin Cheng, Po-Yuan Huang 
  Abstract: This study explored the relationship between container throughputs and liner shipping connectivity for coastal countries. We use UNCTAD data to investigate the spatial relationship between container throughput and liner shipping connectivity across a sample of 138 coastal countries. We demonstrated empirically that container throughputs are spatially clustered: the container throughput of a coastal country is similar to those of its neighbouring countries and trade agreement partners. We also showed there is a spillover effect of container throughputs; one coastal countrys throughput is explained by those of other countries through spatial connections. The growth in one coastal countrys container throughput has a positive ripple effect on the global economy, leading to higher throughputs in other countries. We measure the total effect of liner shipping connectivity on container throughputs, as well as compare the effects transmitted to neighbouring countries based on sea distances with those transmitted to partner countries signed trade agreements. The studys findings suggest that understanding and enhancing liner connectivity is essential for optimising container throughputs at the country level, emphasising the critical role of network structure and technological advancements in shaping maritime transport dynamics.
  Keywords: liner shipping performance index; LSCI; container throughputs; connectivity; neighbouring countries; free trade agreement; spatial dependence.
  DOI: 10.1504/IJSTL.2025.10071913
   
  
• Collaborative scheduling of coal terminal loading-unloading based on hybrid flowshop model considering two-stage zero-waiting and task release time  
  by Meng Yu, Yi Yu, Xiabin Zhang, Lijun He 
  Abstract: The coal terminal is vital in the north coal south transportation strategy, supporting coal supply chain efficiency. Its operations - offloading, stacking, reclaiming, and loading - mirror a hybrid flowshop model but face coordination and constraint challenges. This study explores collaborative scheduling for four-stage operations to minimise completion time and balance equipment load. A multi-objective model with zero-wait loading/unloading is proposed. To solve the NP-hard problem, an improved chaos-based genetic particle swarm optimisation (CBGPSO) algorithm is developed. It combines particle swarm optimisation with a two-stage encoding scheme and a Metropolis-based evolutionary process. Elite crossover and chaos strategies enhance particle perturbation. Real coal terminal data is used for experiments, comparing algorithm performance. Results from multi-train scheduling confirm the model's effectiveness in reducing makespan and improving machine load balance.
  Keywords: hybrid flowshop; coal terminal; loading and unloading integration; multi-objective particle swarm optimisation; collaborative scheduling.
  DOI: 10.1504/IJSTL.2025.10072477
   
  
• Timing of emergency shipboard abandonment decision: an integrated DEMATEL and ANP approach  
  by Volkan Efecan, Ünal Özdemir 
  Abstract: The emergency shipboard abandonment decision is critical for the safety of seafarers, passengers, and the environment. Within the conventions established by the International Maritime Organisation, the captain is expected to order the ships abandonment if a life-threatening hazard persists despite all necessary precautions. This study aims to prioritise the factors that may affect the timing of the abandonment decision, using an integrated DEMATEL and ANP approach. The findings reveal that the captains experience and the psychological pressure they face are critical in the timing of the decision. In conclusion, assessing the timing of shipboard emergency abandonment decisions necessitates the integration of both tangible and intangible aspects, acknowledging the complex interplay between objective data and subjective human elements inherent in crises. Therefore, by identifying the factors and understanding their influence on the decision-making process, more effective emergency procedures can be developed.
  Keywords: abandonment; timing; decision-making; emergency; analytic network process; ANP; DEMATEL.
  DOI: 10.1504/IJSTL.2025.10072817
   
  
• Impact of the transportation organisation integration policy at Ningbo-Zhoushan Port using the double machine learning difference-in-differences model  
  by Jiao Liu, Kaige Zhu, Yuanqiang Zhang, Pengjun Zheng 
  Abstract: In December 2019, Ningbo-Zhoushan Port introduced a transportation organisation integration policy to enhance navigation safety and operational efficiency. To assess the policys impact on vessel navigation safety and efficiency, this paper employs the double machine learning difference-in-differences model, using weighted accidents, weighted incidents, and average waiting time as indicators, to conduct an empirical analysis on three ports within Zhejiang Province and 17 coastal ports across the country. Results show that the 0 coefficients for three indicators were -0.276, -0.314, and -0.523, respectively, all statistically significant at the 1% or 5% levels. These findings indicate that the policy significantly improved both navigational safety and efficiency, with the most pronounced effect observed in reducing vessel waiting time. This highlights the policys stronger impact on efficiency, as reflected by the larger magnitude of the corresponding coefficient. The findings provide robust empirical support for integrated maritime traffic management and inform future policy development.
  Keywords: impact analysis; transportation organisation integration policy; Ningbo-Zhoushan Port; difference-in-differences model; double machine learning; DML.
  DOI: 10.1504/IJSTL.2025.10073668
   
  
• Tramp ship routing problem considering the implementation of carbon intensity indicator  
  by Ming Yin, Kaifei Chang, Dequan Zhou, Xufeng Tang 
  Abstract: In 2023, the International Maritime Organization (IMO) formally implemented the mandatory carbon intensity indicator (CII) rating requirements, linking ships carbon emissions to transport activities. The introduction of CII has significantly impacted shipping companies fleet operation planning. In this paper, we examine tramp shipping companies market contract selection and fleet scheduling under the backdrop of CII implementation. By incorporating the CII ship rating requirements into the constraints of a tramp ship routing and scheduling optimisation model, we expand the current research on the tramp ship routing problem to consider new carbon emission regulations. Additionally, a tailored adaptive large neighbourhood search (ALNS) algorithm is designed to provide a solution tool for large-scale instances of the model. Finally, we perform sensitivity analysis experiments on the model using multiple sets of different scales. The multifaceted impact of CII implementation on the fleet operation of shipping companies is discussed based on the experimental results.
  Keywords: carbon intensity indicator; CII; tramp shipping; ship scheduling; batched cargo selection; adaptive large neighbourhood search; ALNS.
  DOI: 10.1504/IJSTL.2025.10073705
   
  
• Volatility spillover effects of crude oil futures on tanker freight rates: new evidence from a time-frequency perspective  
  by Hongyue Guo, Xinru Li, Wenjuan Jia, Bin Meng, Cong Sui 
  Abstract: In this study, we investigate the volatility spillover impact of oil prices on tanker freight rates, by calculating the monthly volatilities of eleven representative tanker freight indices, West Texas Intermediate (WTI), and Brent futures price indices to measure the oil and tanker shipping markets risk, respectively. In particular, the high-frequency component of the tanker freight rate volatility is disentangled by adopting the ensemble empirical mode decomposition (EEMD) method and Fine-to-coarse algorithm. Besides, the time-varying parameter vector autoregressive (TVP-VAR) model is employed to analyse the impact of crude oil futures prices on the high-frequency component of tanker freight rates at the volatility level. Our results reveal that crude oil price volatility affects tanker freight rate volatility on different routes to varying degrees, and crude oil price volatility has a positive spillover effect on tanker freight rate volatility on short-haul routes and small-sized ships located on routes.
  Keywords: crude oil future; tanker freight rates; high-frequency component; volatility; EEMD model.
  DOI: 10.1504/IJSTL.2025.10074001
   
  
• Research on the optimisation of equipment configurations in smart ports based on self-adaptive theory  
  by Fayi Huang, Dequan Zhou, Yuhan Yang, Xufeng Tang 
  Abstract: The importance of international maritime transportation in global trade is self-evident. However, the increasing frequency of maritime trade has imposed greater demands on maritime supply chains. This study aims to investigate the efficient scheduling of multitier equipment in automated container terminals. An integrated model encompassing berths, container yards and transportation subsystems is considered. Owing to the complexity of the proposed model, a comprehensive optimisation framework is developed by combining mathematical optimisation and simulation optimisation methods, along with the application of self-adaptive theory, to achieve optimality for specific indicators in the model. Finally, numerical experiments using real-world data are conducted to verify the effectiveness of the proposed model and algorithm.
  Keywords: adaptive genetic algorithm; AGA; simulation optimisation; mixed integer programming; port equipment scheduling.
  DOI: 10.1504/IJSTL.2025.10071355
   
  
• Hub-and-spoke network design: disruption mitigation and resilience enhancement  
  by Dengyuhui Li, Dongning Liu, Jianbin Jiao, Shouyang Wang, Guanghui Zhou 
  Abstract: As maritime uncertainty escalates, the unpredictable disruptions pose serious challenges to optimisation decisions. This study aims to design a hub-and-spoke network considering disruption mitigation and resilience enhancement. The patterns of complete or partial disruption of pivotal nodes and connecting paths in a network are analysed, and resilience strategies considering absorptive, adaptive, and restorative capabilities are discussed. A bi-objective mixed-integer linear programming optimisation model is constructed that considers allocation and reinforcement decisions before disruptions and restoration decisions after disruptions, with the minimum economic cost and maximum resilience level. Subsequently, a non-dominated sorting genetic algorithm is proposed, which includes a two-stage initial population generation method and self-adaptive local search strategies. Numerical experiments validate that the proposed model and algorithm can effectively enhance the system resilience while optimising the economic cost. Furthermore, a case study is presented in the context of the Asia-Europe trade corridor. Sensitivity analyses and managerial insights are also provided.
  Keywords: maritime transport; international supply chain; hub-and-spoke network; disruption; resilience.
  DOI: 10.1504/IJSTL.2025.10071892
   
  
• Optimal second-tier hub port for enhanced infrastructure connectivity in the Regional Comprehensive Economic Partnership  
  by Narthsirinth Netirith, Mingjun Ji 
  Abstract: This paper explores the strategic positioning of second-tier hub ports within the Regional Comprehensive Economic Partnership (RCEP). The primary aim is to augment maritime transport and seabound trade by optimising containerisation transhipment and distribution processes. This paper addressed a specialised variant of the single hub location-allocation problem by focusing on a designated second-tier hub port within the RCEP region. This study describes the optimal placement of this hub port and the corresponding feeder port allocations to enhance transhipment efficiency, regional connectivity, and feeder service distribution throughout the RCEP. This analysis identifies Songkhla Port as the most suitable location for establishing a second-tier hub port by utilising an integer linear programming model tailored for single allocation scenarios. The findings provide valuable insights that could strengthen the development and execution of evidence-based policies and strategic initiatives, thereby strengthening maritime infrastructure and promoting economic integration across the RCEP.
  Keywords: hub-and-spoke system; single hub location-allocation; second-tier port; regional connectivity; Regional Comprehensive Economic Partnership; RCEP.
  DOI: 10.1504/IJSTL.2025.10071978
   
  
• Governance strategies for emission control areas: a tripartite game perspective of port state, flag state and shipping company  
  by Jihong Chen, Aoyu Li, Lang Xu, Jinyu Xu, Chengkun Liu, Jianghao Xu 
  Abstract: To reduce ship emissions during navigation and berthing, the IMO has established emission control areas (ECAs), but their effectiveness remains limited. To address fragmented regulations and weak compliance incentives, we develop a tripartite evolutionary game model involving port states, flag states, and shipping companies, revealing the dynamics of collaborative governance. Results show that port states' unilateral regulation faces diminishing returns, and penalties alone are insufficient. Flag state participation depends on effective reputation incentives, with a threshold between international benefits and regulatory costs. Coupled parameter analysis highlights the leverage of governance synergy on cost optimisation and the role of regulatory success in shaping shipping company strategies. This study proposes an incentive-compatible framework for transboundary regulation, offering theoretical support for overcoming sovereignty barriers and enhancing global maritime emission governance.
  Keywords: emission control area; ECA; evolutionary games; cooperative regulation; synergistic effect.
  DOI: 10.1504/IJSTL.2025.10071979