International Journal of Shipping and Transport Logistics (6 papers in press)

Regular Issues

• 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
   
  
• 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 country's throughput is explained by those of other countries through spatial connections. The growth in one coastal country's 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 study's 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 ship's 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 captain's 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 policy's 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 θ₀ 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 policy's 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