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Maritime propulsion is recognized as a hard-to-abate sector and its decarbonization will therefore require transversal efforts, including the introduction of alternative fuels to reduce CO 2 emissions. Both ammonia and hydrogen could provide clean power; however, forecasts hint that ammonia will be especially useful for longer routes, while hydrogen suffers from low volumetric energy density. This paper evaluates the feasibility of a cargo ship with a SOFC powertrain equipped with LOHC-based hydrogen storage and compares the sizing and heat management requirements of four LOHC systems, namely N-ethylcarbazole (NEC), dibenzyltoluene (DBT), methylcyclohexane (MCH), decaline (DEC), with an ammonia-based one. The size of the 8.4 MW SOFC system is similar for the five carriers as expected. The dynamic performance of the LOHC system shows that the hydrogen flow rate can be effectively controlled by acting on the LOHC flow rate, reactor temperature, and pressure. However, LOHC systems are heavier (by a factor of 1.6 to 2.1) and larger (by 1.6 to 2.3 times) than ammonia systems. The decalin system results in the lowest mass and volume, while NEC is the heavier, and MCH is the least dense of the evaluated LOHCs. Similarly, the utilization of SOFC waste heat to cover dehydrogenation heat ranges from 45.6 % (NEC) to 27.9 % (ammonia). Overall, even considering the lower reaction temperature, LOHCs do not appear to be competitive with ammonia as hydrogen storage systems in the maritime sector. • Liquid organic hydrogen carrier (LOHC) systems discussed for maritime applications. • Different LOHC systems are sized, and the heat demand is evaluated. • Control strategies are devised to meet instantaneous hydrogen demand. • The dynamic response of LOHC-based systems is more than satisfactory. • Comparison with ammonia is unfavorable in terms of mass, volume and heat demand. [ABSTRACT FROM AUTHOR]

Liquid sloshing within partially filled tanks of large liquid cargo ships has been a major concern in marine engineering. An arbitrary Lagrangian–Eulerian (ALE) finite element (FE) method is proposed to simulate three-dimension large-amplitude liquid sloshing in ellipsoidal tanks, and its effectiveness is verified by experiments. Firstly, a scheme of the fractional step algorithm for solving the Navier–Stokes (NS) equations, combining with the characteristic-based split (CBS), in the ALE framework is constructed. Then a deft and effective mesh moving and update strategy is designed for large-amplitude liquid sloshing in ellipsoidal tanks. Subsequently, computer programming and numerical simulation are carried out and the obtained results show excellent agreements with the experiments. Finally, the nonlinear phenomena for large amplitude liquid sloshing in ellipsoidal tanks under the external excitations are investigated and the multi-modal characteristics of liquid nonlinear sloshing is revealed through a combination of numerical simulations and the ground physical experiment. [ABSTRACT FROM AUTHOR]

The assessment of ship manoeuvring properties is a crucial part of the process of ship design and is usually first carried out during the model test phase of the project. According to the International Maritime Organisation (IMO), the manoeuvrability of the ship can be assessed on the basis of the standard trial manoeuvres. In order to do this, free running model tests or captive model tests are used, in conjunction with a mathematical model of ship motion; this is considered to be a reliable prediction method. In recent years, numerical-based methods have also been widely used in ship hydrodynamics and constantly improving computing power and more accurate fluid dynamics models have made the simulation of more complex cases possible. The study presented in this paper focuses on the determination of propeller-rudder-hull interaction coefficients based on the Mathematical Modelling Group (MMG) standard method in ship manoeuvring prediction. The identification of the parameters uses both captive model tests and a simplified numerical method, as well as regression formulas. The results of 35° turning and 10°/10° zig-zag manoeuvres, obtained with the use of each prediction method, are then compared. The test case used in the study is the container type cargo ship equipped with a single propeller and rudder. The model scale, for which the referenced model tests were carried out, is equal to 1:25 and a NACA 0020 rudder profile was used. This research highlights the advantages and disadvantages of each presented prediction method and their potential for future improvement. [ABSTRACT FROM AUTHOR]

Mandatory use of low-sulfur fuel according to the global sulfur limit regulation has reduced the emissions of SO2 and particulate matter (PM) significantly on ships, and it also leads to a very large uncertainty in volatile organic compound (VOC) emissions. Therefore, an on-board test of VOCs from nine typical cargo ships with low-sulfur fuels in China was carried out in this study. Results showed that the emission factor of VOCs (EFVOCs) varied largely from 0.09 to 3.01 gkg-1 of fuel, with domestic coastal cargo ships (CCSs) having the highest level, followed by inland cargo ships (ICSs) and ocean-going vessels (OGVs). The switch of fuels from heavy fuel oil (HFO) to diesel increased EFVOCs by 48 % on average, which enhanced both O3 and secondary organic aerosol (SOA) formation potential, especially for OGVs. Besides, the use of low-sulfur fuels for OGVs also led to a significant increase in naphthalene emission. These indicated that the implementation of a global ultra-low-sulfur oil policy in the near future needs to be optimized. Moreover, aromatics were the most important common contributors to O3 and SOA in ship exhausts, which need to be controlled as a matter of priority. It was also found that the benzene, toluene, and ethylbenzene ratio of 0.5:0.3:0.2 on average could be considered a diagnostic characteristic to distinguish ship emissions from other emission sources. [ABSTRACT FROM AUTHOR]

Tinna Rubber and Infrastructure Limited (TRIL) is India's largest integrated material recycler of end-of-life tyres (ELT). It imported 70% scrap to feedstock in its manufacturing plants. The nationwide lockdown declared on 24 March 2020 posed severe initial restrictions on the movement of non-essential cargo. It affected TRIL's 265 containers lodged at different ports in the country, thus escalating their demurrage/detention charges and storage costs. This case concerns supply chain problems faced by Shanti Swarup, TRIL Head–Procurement, owing to COVID-19 disruption. The situation was severe enough to wipe out TRIL's annual cash profit and put its factories at risk of running out of feedstock. Scrap importers, like TRIL, were in a deadlock with shipping lines and freight stations to waive any imposed charges or avail of any monetary relief despite regular guidelines issued by the Indian government. However, Swarup's existing and effective 'supply chain resilience' strategies had already made TRIL win half the battle by adopting a different approach to the deadlock problem, which relieved the situation. The case study also highlights typical risks and challenges faced by the Indian ELT recycling industry. [ABSTRACT FROM AUTHOR]

This article provides information on various shipwrecks in the Moreton Bay area, with approximately 122 recorded shipwrecks in total. The wrecks are located in different areas such as Bribie Island, Peel Island, North Stradbroke Island, Cape Moreton, and Moreton Island. Specific wrecks mentioned include the PS Avon, PS Kate, No 6 Hopper/Mount Elliot, SD Platypus 1, SS Lady Loch, and Rufus King Liberty Ship EC2-S-C1. The article also includes information about the history and characteristics of these wrecks. Additionally, it mentions several ships that have been sunk at the Curtin Artificial Reef off Moreton Island, including the AHS Centaur, which was a hospital ship sunk by a Japanese submarine during World War II. [Extracted from the article]

Simple Summary: The casuarina moth, Lymantria xylina Swinhoe (Lepidoptera: Erebidae), may become a major invasive pest similar to Lymantria dispar Linnaeus (Lepidoptera: Erebidae), and the risk of its spread has attracted worldwide attention. Male L. xylina moths have strong flight ability, while female moths have weaker flight ability. Female moths frequently rest on branches and can sometimes fly short distances. Additionally, females may be attracted by the lights of ships and land on the hull or cargo to lay eggs. Prior to this study, little was known about the flight ability of L. xylina, due to the absence of related research. Consequently, our investigation focused on assessing the potential flight ability of L. xylina adults using a flight mill. We conducted a comprehensive evaluation of the flight ability of L. xylina moths in terms of age, sex, flight duration, mating, oviposition, wing morphology, and under different temperatures. The goal was to provide a theoretical framework for understanding the flight characteristics and dispersal potential of L. xylina, as well as to assess the risk of dispersal through ocean-going freighters. Lymantria xylina Swinhoe (Lepidoptera: Erebidae) is a potentially invasive pest, similar to Lymantria dispar asiatica Vnukovskij and Lymantria dispar japonica Motschulsky (Lepidoptera: Erebidae). To evaluate its potential for spread and flight distance related to egg deposition on vessels at ports, we employed a flight mill to assess the flight capabilities of its adults under varying conditions. Our findings revealed that females primarily flew short distances and ceased flying after 3:00 AM, whereas males covered much longer distances throughout the day. Sex, age, and flight duration significantly influenced flight ability. Females exhibited weaker flight capability than males, and their ability declined with increasing age or flight duration. Notably, 1-day-old moths displayed the strongest flight ability, with average flight distances of up to 3.975 km for females and 8.441 km for males. By the fifth day, females no longer flew, and males experienced reduced flight ability. After continuous hanging for 16 h, females lost most of their flight capacity, while males remained capable of flight even after 32 h. Additionally, female flight ability decreased significantly after mating, possibly due to factors such as egg-carrying capacity, weight, and load ratio. This study provides a foundation for assessing the risk of long-distance dispersal of L. xylina via ocean-going freighters, considering female moths' phototactic flight and oviposition. [ABSTRACT FROM AUTHOR]

Forward Freight Agreements (FFAs) are exchange-traded futures and the main means of risk management for shipping spot freight. The relationship between the FFA market and the shipping spot market has attracted much attention, but few studies focus on the dynamic FFA term structure and its correlation with the spot price. In this study, we establish the dynamic term structure of the FFA market by quantifying the level factor, the slope factor and the curvature factor of the FFA term structure to reveal the underlying information in the shipping derivatives market, and further scrutinize the impact of the FFA term-structure factors on the shipping spot market. The empirical results indicate that the term-structure factors have significant time-varying effects on the BDI and BPI: The effect of the term-structure factors on BDI and BPI changes with shipping market conditions and economic environment. The level factor has a positive effect, while the slope factor and the curvature factor both have negative effects, with the impacts on the BPI being about twice as large as the impacts on the BDI. The three factors all have their strongest effect in the short term and the weakest effect in the long term. [ABSTRACT FROM AUTHOR]

Recently, cryogenic fluids are widely transported via cargo ships as energy sources. The generation of boil-off gas (BOG) is inevitable in a cryogenic container due to the large temperature difference. Therefore, accurately analyzing the boil-off gas over time is essential to increase delivery efficiency and ensure tank safety. However, predicting the boil-off rate (BOR) is not a simple task, as both experiment and calculation require a significant amount of time. In this study, a simple predictive method is developed for simulating a 1/50 scaled model tank. The method consists of steady and quasi-unsteady calculations. Steady calculations are performed to establish a correlation between LN2 level and inner-wall temperature. Quasi-unsteady calculations simulate BOG over time by changing the inner-wall boundary conditions. This method can help engineers effectively evaluate the insulation performance of a cryogenic container in a short time and provide guidelines for simulating a real scale tank. [ABSTRACT FROM AUTHOR]

Everywhere carriers incur a measure of liability for the safety of the goods. Carriers are liable for any damage or for the loss of the goods that are in their possession as carriers unless they prove that the damage or loss is attributable to certain excepted causes. Damaged and lost items can unfortunately be a common problem when shipping freight. Legal responsibilities arise due to loss or damage during transit while cargo is in their care. This study intends to investigate the nature of the liability of the maritime carrier when this liability is realized, and the extent to which it can be paid or disposed of given the risks realized from the transportation process, which may result in damage or loss of the goods, and the damage that may cause to the consignee because of this damage or loss. [ABSTRACT FROM AUTHOR]

Transport of cargo by short-sea shipping is at the forefront of the European Union's transportation policy. It has the promise to alleviate congested land transport and decrease pollution [European Commission. 2021. Putting European transport on track for the future]. However, the shortage of qualified personnel might impede this solution. Autonomous sailing of ships could help, especially if the whole trip is automated. In this study a control system is designed that is capable of sailing a round-trip with a model-scale feeder vessel in Marin's Seakeeping and Manoeuvring Basin. The Guidance-Navigation-Control framework is used to sail this journey with attention given to smooth switching between the operational modes. A set of experiments is conducted to validate the controller and identify crucial parts in the operation. The experiments showed that the controlled vessel can sail a round-trip with different levels of waves and wind disturbances coming from different directions. Furthermore, the round-trip can be modified such that the approach angle to the quay changes and the ship still successfully docks at the quay. It was found that the approach to the quay is most difficult during transition from high to low speed, when the bow thrusters have yet to become effective, and a large change in course is needed. This can be circumvented by changing the trajectory to the quay to have a longer straight approach, or it can be corrected when the bow thrusters become active. [ABSTRACT FROM AUTHOR]

Point cloud-based 3D small object detection is crucial for autonomous driving and smart ships. The current 3D object detection mainly relies on object global features derived from 3D and 2D convolutional networks, inevitably leading to the loss of substantial object detail information. As large objects contain enough points to obtain sufficient global features, they are easy to identify. In contrast, small objects contain fewer points and their global features are weak, resulting in false classifications and inaccurate location estimates. Therefore, it is necessary to take into account the local geometric relation features of the object to develop adequate discriminative features. Moreover, the current two-stage 3D object detection speed is relatively slow due to the complex refinement structure, which is adverse to real-time detection. In this paper, an efficient 3D small object detection network with two novel modules is proposed. Firstly, the Geometric relation-based Feature Aggregation (GFA) module is designed to improve small object detection performance. This module flexibly aggregates the features of voxels and original points near the key points, for key points to aggregate more local discriminate features of objects, which is conducive to small object detection. Subsequently, the Key point Feature Abstraction (KFA) module is designed to improve the speed of small object detection, through which object global features can be rapidly obtained and the detection performance can be enhanced. Experimental results show that this method achieves state-of-the-art small object detection performance on both the KITTI dataset and the River Cargo Ship dataset. [ABSTRACT FROM AUTHOR]

Considering the unobserved spatial heterogeneity, this study aims to build a Bayesian spatial multinomial logistic (BSMNL) model by utilizing the geographic information from historical maritime accidents. The proposed BSMNL model can be applied to investigate the determinants of human errors involved in maritime accidents. Compared to the traditional multinomial logistic (MNL) model, the proposed BSMNL model produces a more accurate estimate of the effects of environmental and accident factors on the occurrence likelihood of human errors in maritime accidents. Results show that accidents involving cargo and container ships; tankers carrying liquefied natural gas (LNG), liquefied petroleum gas (LPG), or oil; and fishing vessels are more likely to be associated with human errors. Further, one important finding is that the involvement of fishing vessels significantly increases the occurrence probability of both negligence errors and judgment or operational errors. In addition, the occurrence likelihood of human errors is generally higher in springtime, conditions of poor visibility, the absence of strong winds or waves, and the moored or docked status. [ABSTRACT FROM AUTHOR]

This article provides an overview of deep ocean expeditions conducted using the MIR-1 and MIR-2 deep manned submersibles. The main objectives of these expeditions were to search for and observe the deepest wooden wreck and the deepest military submarine wreck. The article discusses the techniques and methods employed during these operations. The expeditions were driven by the need to financially sustain the submersibles and the group of professional submariners. Additionally, the article mentions the discovery of a Spanish galleon at a depth of 4,700 meters and the search for a Japanese submarine from World War II. The text also describes two expeditions to locate and explore the wreckage of the I-52 submarine, which sank in 1944. The first expedition in 1995 was unsuccessful due to incorrect coordinates provided by British historians. However, a second expedition in 1998 led by U.S. historian Paul Tidwell successfully located the submarine using archival materials and sonar technology. The exploration of the wreckage revealed significant damage from torpedoes and the absence of gold ingots. Overall, these expeditions were primarily focused on scientific research and the utilization of the MIR submersibles. [Extracted from the article]

Maritime transportation is crucial for global trade and responsible for the majority of goods movement worldwide. The optimization of maritime operations is challenged by the complexity and heterogeneity of maritime nodes. This paper presents the emerging deployment of federated learning (FL) in maritime environments to address these challenges. FL enables decentralized machine learning model training, ensuring data privacy and security while overcoming issues associated with non-i.i.d. data. This paper explores various maritime use cases, including fuel consumption reduction, predictive maintenance, and just-in-time arrival. Experimental results using real datasets demonstrate the superiority of FL in predicting the fuel consumption of large cargo ships in terms of accuracy and spatiotemporal complexity over traditional collaborative machine learning approaches. The findings indicate that FL can significantly improve the performance of fuel consumption models in a collaborative way, while ensuring data privacy preservation and no data transmission during the learning process. Finally, this paper discusses open issues and future research directions necessary for the widespread adoption of FL in maritime transportation and settings. [ABSTRACT FROM AUTHOR]

In recent years, carbon emission reduction in the shipping sector has increasingly garnered scholarly attention. This study delves into the pathways for carbon emission reduction in shipping across the Yangtze River, emphasizing fuel alternatives. It initiates by introducing a novel ship carbon emission calculation methodology predicated on voyage data, followed by the development of a predictive model for ship carbon emissions tailored to specific voyages. Then, emission reduction scenarios for various voyage categories are designed and exemplary alternative fuels selected to assess their potential for emission mitigation. Subsequently, scenario analysis is employed to scrutinize the CO2 emission trajectories under diverse conditions, pinpointing the most efficacious route for carbon emission abatement for inland vessels. Finally, the proposed method is applied to the middle and lower reaches of the Yangtze River. The results indicate that accelerating the adoption of alternative fuels for long-distance cargo ships would greatly accelerate the development of environmentally friendly shipping. Under a scenario prioritizing zero-carbon growth, emissions from inland vessels are anticipated to reach their zenith by 2040. These findings can provide theoretical guidance for emission reductions in inland shipping and effectively promote the green and sustainable development of the shipping sector. [ABSTRACT FROM AUTHOR]

We explore how the hub-and-spoke system in the international freight transportation network contributes to the global shrinkage of space. The friction in long-distance trade routes varies by the location of shippers and nodal characteristics of traversed ports, and is mitigated by the quality of scale economies driven by the hub-and-spoke distribution system along the trajectory of the logistic process. In order to confirm the shrinkage of space brought about by the hub-and-spoke shipping economies through transshipment routes via hub ports, we examine disaggregated cross-Atlantic cargo shipping trajectory data from Europe to the U.S. recorded both on landside and seaside with a discrete choice model. The results present that hub-and-spoke shipping economies arise with the scales of landside and maritime port operations and with shipping line diversity. Generally, they are found to offset distance friction that occurs along landside and maritime shipping voyages, but hub-and-spoke shipping economies arise differently depending on how hub-and-spoke configurations are set. They mainly stem from larger scale of ports' operation and more diverse shipping lines serving the final port of export. The hub-and-spoke system is confirmed as a main driver of global shrinkage of space in terms of long-distance commercial activities. [ABSTRACT FROM AUTHOR]

Standard structural assessments of ship hulls include the evaluation of the elastic structural response. Elastic analysis neglects extreme and unpredicted loadings, which can produce catastrophic outcomes, such as the loss of the ship's ultimate strength. Moreover, hull elements are considered unaffected by age-related degradation. Therefore, this study models and quantifies the effect of corrosion-induced structural degradation on the ultimate strength of a high-tensile-steel (HTS) cargo ship using progressive collapse and nonlinear finite element methods. Uniform and pitting corrosion are modeled through selected scenarios, which hull elements might encounter during exploitation, producing a total of 148 calculation models. The findings show that corrosion-induced degradation can significantly decrease the ultimate strength of the hull (up to 30% for the most severe scenarios assessed). Furthermore, ultimate strength decreases almost proportionally to the amount of wastage considered. It was found that stiffener corrosion has a significant effect on the total ultimate strength. This study's aim is to emphasize the vast importance of including ultimate strength along with ageing effects in industry-standard structural assessments of large HTS ship structures, designed to last for several decades whilst exposed to excessive and unpredicted bending moments. [ABSTRACT FROM AUTHOR]

The global shipping network (GSN) has been suggested as a pathway for the establishment and reintroduction of Aedes aegypti and Aedes albopictus primarily via the tire trade. We used historical maritime movement data in combination with an agent-based model to understand invasion risk in the United States Gulf Coast and how the risk of these invasions could be reduced. We found a strong correlation between the total number of cargo ship arrivals at each port and likelihood of arrival by both Ae. aegypti and Ae. albopictus. Additionally, in 2012, 99.2% of the arrivals into target ports had most recently visited ports likely occupied by both Ae. aegypti and Ae. albopictus, increasing risk of Aedes invasion. Our model results indicated that detection and removal of mosquitoes from containers when they are unloaded effectively reduced the probability of mosquito populations establishment even when the connectivity of ports increased. To reduce the risk of invasion and reintroduction of Ae. aegypti and Ae. albopictus, surveillance and control efforts should be employed when containers leave high risk locations and when they arrive in ports at high risk of establishment. Author summary: Our study investigates how the global shipping network inadvertently serves as a highway for the spread of two mosquito species, Aedes aegypti and Aedes albopictus, both of which are vectors for pathogens causing diseases like dengue and Zika. We analyzed maritime movement data in the United States Gulf Coast and found that the more cargo ships that dock at a port, the higher the chance these mosquitoes will be introduced; nearly all cargo ships arriving at these ports had last visited regions where these mosquitoes thrive, significantly raising the risk of spread of these mosquitoes. Our research also suggested that proactive detection and elimination of mosquitoes from shipping containers can dramatically lower the risk of these pests establishing new colonies, even as global shipping traffic grows. Our work suggests that by enhancing surveillance and control measures at strategic points in the shipping process, we can safeguard our communities from additional mosquito introductions. [ABSTRACT FROM AUTHOR]

Understanding the determination mechanism and dynamics of shipping freight rates has significant implications for practitioners, economists, and regulators of maritime transport. This paper systematically reviews the relevant papers on shipping freight rate published between 2000 and 2019. Specifically, it provides empirical insights including the major influencing factors of shipping freight rates and differences among the shipping sectors, and discusses the dominant methods and their applicability, strengths and weaknesses, and opportunities for new methods. Furthermore, the omissions and limitations in methods are explored to identify the research gaps and set a future research agenda. It is found that there is a strong focus on temporal dynamics with a wide range of modelling methods applied, while discussion on cross-sectional dynamics on how shipping freight rates are determined by vessel characteristics, contract terms, market competition, etc., is limited. Besides, the collaboration network analysis shows that more knowledge sharing and cross-discipline collaboration efforts can create potential for more inspired insights with advanced methods in this field. [ABSTRACT FROM AUTHOR]

This article focuses on the shared history of Frankfurt Zoological Garden and Airport, developing an infrastructural perspective on the rise of behavioral thinking in postwar environmental sciences. It shows that technical and logistical environments, such as seaports, airports, train stations, and highways, shaped the way environmental scientists and a broader public conceptualized animal behavior. Similar to ergonomics and human factor engineering in the 1950s and '60s, human-made spaces and interiors became central reference points for developing and testing new ideas on the interaction between animals and "the environment." Further, airports were sites of knowledge transfer between practitioners, including animal traders, care attendants, veterinarians, logistics experts, and scientists. The first part of the article draws on the works of biologist and Frankfurt's Zoo director Bernhard Grzimek, who made excessive use of air cargo to ship wild animals to Frankfurt. The second part traces the emergence of new spaces for animals at Frankfurt Airport in the 1950s--such as the "animal room" in the cargo area. The third part of the article uncovers the hidden networks of animal traders and shipping companies that made Frankfurt Airport a major international hub in animal air cargo. Lastly, the article argues that hands-on experience of animal behavior, such as that conducted in airports like Frankfurt, is part of a broader pattern of environmental knowledge production in in the twentieth century--in close proximity to infrastructure projects. [ABSTRACT FROM AUTHOR]

Seabird-vessel interactions are often studied through the lens of fisheries bycatch, but seabirds encounter many watercraft types. Western Gulls Larus occidentalis breeding on the Farallon Islands (California, USA) have a foraging domain that encompasses both shipping lanes and productive fishing grounds, resulting in ample opportunities for vessel encounters. Previous research showed that these Western Gulls can serve as ecosystem indicators because their foraging behavior is linked to ocean prey conditions, and because their foraging grounds overlap with that of Humpback Whales Megaptera novaeangliae, which can make prey accessible. Because ship strikes and entanglement in fishing gear are concerns for whales in this region, we investigated gull-vessel interactions as a proxy for identifying whale ship-strike risk by assessing the geographical overlap between GPS-tracked gulls and vessels using the Automatic Identification System. During 2014-2019, 40% of tracked gulls encountered a vessel, resulting in 85 encounters. Gulls mostly encountered cargo ships and tug/pilot boats, mainly within the shipping lanes (79%). Over 30% of these encounters co-occurred with gull foraging events, and most encounters were situated within shipping lanes (80%). Moreover, most gull foraging events began before the vessel encounters, which appeared to interrupt gull behavior. Interannual variability of encounters was mainly related to gull foraging locations: during years of high oceanic productivity, foraging more frequently occurred at sea rather than nearshore or on land, leading to more encounters with ships. This study builds on work that documented overlap between Humpback Whales and Western Gulls but did not test whether foraging gulls encountered vessels. We found that some vessel encounters coincided with gull foraging events; from that, we suggest that the real-time processing of seabird tracking data could provide additional information on whale distribution (which is more difficult to study) within regions of high ship-strike risk and could be included as another tool for dynamic ocean management. [ABSTRACT FROM AUTHOR]

This paper presents a method for developing and testing a risk-based control system, as a first step towards including the human supervisor explicitly in the design of the system. The result is a control system with improved decision-making capabilities compared to existing control systems. The methodology presented in the paper uses the Systems Theoretic Process Analysis (STPA) to analyse the risks of an autonomous ship within its concept of operations (CONOPS), and a Human-STPA (H-STPA) is used to analyse human responsibilities and involvement. The STPA results are then used to construct a Bayesian belief network (BBN)-based risk model to assess the operational risk of the ship. This is represented as a risk cost, describing the expected cost of consequences caused by potential hazardous events. This cost is combined with fuel costs, operations costs, and the potential loss of income if new missions are not undertaken using a supervisory risk controller (SRC). The SRC is capable of making decisions about how the ship should be safely operated and notifies the human supervisor in due time when it is necessary for them to take control. The last part of the methodology presented in this paper is testing the control system using a set of verification objectives based on results from the STPA and H-STPA. A case study involving an autonomous cargo ship with a human supervisor located in a remote operation center (ROC) is included; it shows that the proposed control system can operate the ship safely in different conditions and situations. By designing the SRC to notify the human supervisor before it reaches its operational limit, the ship is able to operate in a wider range of conditions compared to when just the autonomous control system is in charge. Hence, the proposed methodology shows promising results and provides useful insights related to shared control for autonomous ships. [ABSTRACT FROM AUTHOR]

The escalating impact of anthropogenic activities on global climate patterns necessitates urgent measures to reduce emissions, with the maritime industry playing a pivotal role. This article aims to examine the adoption of International Maritime Organization energy efficiency measures for the often-overlooked fishing vessels and their contribution to the overall maritime decarbonization efforts. The article analyzes the attained technical efficiency indices of a case study large-scale fishing vessel and compares them with those of two cargo ships where IMO measures already apply. To support the proposal, a comprehensive analysis of the energy efficiency indices of eight large purse seine fishing vessels is also presented. The results show that large-scale fishing vessels of 400 GT and above could be subject to the IMO energy efficiency measures. The operational challenges, unique to the fishing sector, suggest that sector-specific considerations may be required to integrate the fishing fleet into the already existing IMO energy efficiency guidelines. Looking ahead, this article explores the benefits of aligning Regulation (EU) 2023/957 and IMO guidelines, as well as applying the IMO Carbon Intensity Indicator (CII) in assessing the operational environmental impact of fishing operations, emphasizing the importance of including these vessels in the current regulatory frameworks to promote decarbonization. [ABSTRACT FROM AUTHOR]

Port State Control (PSC) inspections conducted under the Paris Memorandum of Understanding (MoU) agreement have become a crucial tool for maritime administrations in European Union countries to ensure compliance with international maritime safety standards by ships entering their ports. This paper analyses all PSC inspections conducted in 10 major European ports belonging to the Paris MoU between 2012 and 2019. For its study, a multivariate HJ-Biplot statistical analysis is carried out, which facilitates the interpretation and understanding of the underlying relationships in a multivariate data set by representing a synthesis of the data on a factorial plane, with an interpretation that is very intuitive and accessible for readers from various fields. Applying this method with ship characteristics as explanatory variables, several classifications were derived. These classifications align with the annual performance lists published by the Paris MoU and the International Association of Classification Societies list, suggesting that this method could serve as a reliable classification approach. It provides maritime authorities with an additional indicator of a ship's risk profile, aiding in the prioritising of inspections. The method also effectively categorises ports and types of ships used for cargo transport, offering insights into the specific maritime traffic each port experiences. Furthermore, this study identifies characteristics associated with substandard ships, which is a primary objective of PSC inspections. Beyond revealing these traits, this research underscores the existence of several readily applicable techniques to enhance maritime safety and reduce the risk of ocean pollution. [ABSTRACT FROM AUTHOR]

This work analyses the activities of Genoese merchant communities in the grain trade in western Mediterranean markets. Our goal is to shed light on their ability to integrate into foreign lands, taking advantage of their privileged position within the Spanish Crown. Our analysis is focussed on two case studies, strictly connected from a theoretical point of view: Sicily and Tabarka. Both Genoese minorities living on these two islands used the port of Genoa as their commercial hub. Regarding Sicily, this study has mostly drawn information from a yet unexploited source: general average procedures drawn up in Genoa. General average (GA) was (and still is nowadays) a legal instrument used in maritime trade to share between all parties involved the expenses which can befall ships and cargoes from the time of their loading aboard until their unloading (due to accidents, jettison, etc.). These documents have been collected in an online database soon to be published as part of the ERC-funded AveTransRisk project. They offer valuable insights on shipmasters and merchants, cargo values, ports of destination, wheat prices, etc. All the sources are available on the online database resulting from the AveTransRisk project, of which we are members (). For the trade in North African wheat, we have mostly used documents related to the Genoese 'colony' of Tabarka, administered by the Lomellini family. These sources are kept in the Genoese archives as well as in the Archives Nationales of Paris. [ABSTRACT FROM AUTHOR]

Mandatory use of low-sulfur fuel according to global sulfur limit regulation has reduced the emissions of SO2 and PM significantly on ships, while it also leads to very large uncertainty on VOCs emission. Therefore, on-board test of VOCs from 9 typical cargo ships with low-sulfur fuels in China were carried out in this study. Results showed that emission factor of VOCs (EFVOCs) varied largely from 0.09 to 3.01 g kg-1 fuel, with domestic coastal cargo ships (CCSs) had the highest levels and ocean-going vessels (OGVs) the lowest. The switch of fuels from heavy fuel oil (HFO) to diesel increased EFVOCs by 48 % on average, which enhanced both O3 and secondary organic aerosol (SOA) formation potentials, especially for OGVs. Besides, the use of low-sulfur fuels for OGVs also lead to significant increase of naphthalene emission. These indicated the implementation of globally ultra-low-sulfur oil policy in the near future needs to be optimized. Moreover, aromatics were the most important common contributors to O3 and SOA in ship exhausts, which need to be controlled with priority. It was also found that benzene, toluene, and ethylbenzene ratio of 0.5:0.3:0.2 on average could be considered as a diagnostic characteristic to distinguish ship emission from other emission sources. [ABSTRACT FROM AUTHOR]

BOG re-liquefaction process is a necessary part for the safety of LNG cargo ships, and it is also the most common way to deal with evaporated gas (BOG) in LNG ships. Therefore, how to optimize the re-liquefaction process and save energy consumption is a problem that cannot be ignored in BOG re-liquefaction system. In this paper, based on the traditional BOG re-liquefaction process, a liquid nitrogen precooling circulation system is added and linked with the nitrogen purging system. Aspen HYSYS software was used to simulate and analyze the exergy efficiency, specific power consumption, exergy efficiency in the proposed liquefaction process. In addition, we introduced a bacterial foraging algorithm to optimize the process parameters. According to the operation results, the optimized process has a specific power consumption of 1.028 kWh/kg LNG , which is 21.53 % lower than that of the original NH 3 and CO 2 precooling system. Changing the traditional precooling system to liquid nitrogen tank reduces the complexity of the liquefaction system and improves the reliability of the system. Because liquid nitrogen has excellent cryogenic energy, small size, cheap price, safety in the actual use process and the linkage with the purge device on board, it shows excellent performance in the process of BOG pre-cooling liquefaction. [ABSTRACT FROM AUTHOR]

Workplaces can be tricky for migrant workers like seafarers to navigate, especially on board cargo ships which in recent times have become multi-ethnic in composition. Diverse cultures and individual differences can pose challenges to working relationships on board, which in turn can have negative implications on operational safety. In this context, the article highlights the role of seafarers' sense of place in enacting harmonious socialities and safety culture on board. Sense of place refers to marked positioning in space where seafarers conduct themselves in relation to others in terms of hierarchy. In turn, this helps fashion the collective mind among seafarers as a way of dealing with the challenges of life at sea, including operational safety on board. This article draws from data gathered from fieldwork on board four ocean-going cargo ships and informal conversations with seafarers in seafarer centers in the United Kingdom between 2010 and 2020. [ABSTRACT FROM AUTHOR]

During winter storms in 2014 and 2017, strong waves exposed hundreds of timbers and artefacts at the Belinho beach, in the North of Portugal. These ship remains were later discovered to belong to a 16th-century shipwreck, probably originating from Northern Europe. This paper aims to discuss the importance of cargo analysis through the study of the material culture associated with that site, consisting mainly of hundreds of pewter, brass, lead, iron, and stone artefacts. Most of these objects seem to have belonged to the ship's cargo and are tied to a European trade system reflecting economic, cultural, and symbolic behaviours. [ABSTRACT FROM AUTHOR]

Background: This research conducts a contextual comparative analysis between Dar es Salaam and Mombasa ports, employing a hybrid data envelopment analysis (DEA) model that integrates the contextual value-added approach (CVA). The assessment incorporates various inputs (quay length, number of cranes, and storage area) and outputs (number of ship calls and cargo throughput) to compute efficiency scores, offering nuanced insights into the strengths, weaknesses, and areas for improvement of both ports. Methods: The hybrid DEA model with CVA is applied to calculate efficiency scores, considering the diverse inputs and outputs. This approach allows for a comprehensive evaluation of the relative performance of Dar es Salaam and Mombasa ports. The study also explores the influence of trade-related externalities on port efficiency, providing a holistic understanding of the factors shaping the ports' operational effectiveness. Results: The efficiency scores depict distinctive performance trends between Dar es Salaam and Mombasa ports. Notably, Dar es Salaam exhibits maximum efficiency (efficiency value of 1) in 2018 and 2021, while Mombasa attains optimal performance (efficiency value of 1) in 2021. However, efficiency values fluctuate for both ports in other years, ranging between 0.895 and 0.985 for Mombasa and 0.924 and 0.960 for Dar es Salaam. Conclusions: This study highlights the dynamic efficiency levels of Dar es Salaam and Mombasa ports over multiple years and identifies critical factors influencing their performance. The findings contribute valuable insights to the field of port analysis, offering guidance to port management and policymakers in optimizing the efficiency and competitiveness of these vital maritime hubs. [ABSTRACT FROM AUTHOR]

Despite the Baltic Sea being one of the most intensive shipping regions in the world the potential magnitude of the biofouled hulls in this region is unknown. This study estimated the biofouling load to Baltic Sea Region (BSR) based on the wetted surface area (WSA) method with regard to country, ship type and donor bioregion. WSA flux reached 656 km2, of which 86% was associated with ships operating inside and 14% was WSA flux brought by ships from outside of the Baltic Sea. Most of the WSA was transported to Swedish, Finnish and Danish ports as well. The highest WSA flux was assigned to roll-on/roll-off, passenger and general cargo ships. The high biofouling potential in BSR indicates a potential high risk to the environment and, therefore there is an urgent need for appropriate guidelines to be introduced into daily use by the commercial shipping community. [ABSTRACT FROM AUTHOR]

In this study, real voyage data and ship specifications of a general cargo ship are employed, and it is assumed that diesel generators are replaced with hydrogen proton exchange membrane fuel cells. The effect of the replacement on CO2, NOX, SOX, and PM emissions and the CII value is calculated. Emission calculations show that there is a significant reduction in emissions when hydrogen fuel cells are used instead of diesel generators on the case ship. By using hydrogen fuel cells, there is a 37.4% reduction in CO2 emissions, 32.5% in NOX emissions, 37.3% in SOX emissions, and 37.4% in PM emissions. If hydrogen fuel cells are not used instead of diesel generators, the ship will receive an A rating between 2023 and 2026, a B rating in 2027, a C rating in 2028–2029, and an E rating in 2030. On the other hand, if hydrogen fuel cells are used, the ship will always remain at an A rating between 2023 and 2030. The capital expenditure (CAPEX) and operational expenditure (OPEX) of the fuel cell system are USD 1,305,720 and USD 2,470,320, respectively, for a 15-year lifetime, and the hydrogen fuel expenses are competitive at USD 260,981, while marine diesel oil (MDO) fuel expenses are USD 206,435. [ABSTRACT FROM AUTHOR]

The intricate nature of ships and floating structures presents a significant challenge for ship designers when determining suitable structural dimensions for maritime applications. This study addresses a critical research gap by focusing on a three-cargo hold model for a multipurpose cargo ship. The complex composition of these structures, including stiffening plates, deck plates, bottom plates, frames, and bulkheads, necessitates thorough structural analysis to facilitate effective and cost-efficient design evaluation. To address this challenge, the research utilises FEMAP-integrated NX NASTRAN software (2021.2) to assess hull girder stress. Furthermore, a novel approach is introduced, integrating the Design of Experiments (DOE) principles within Minitab 21.4.1 software to identify critical parameters affecting hull girder stress and production costs. This method determined the top five key parameters influencing hull girder stress: Hatch coaming plate, Hatch coaming top plate, Main deck plate, Shear strake plate, and Bottom plate, while also highlighting key parameters that impact production costs: the inner bottom plate, Inner side shell plate, Bottom plate, Web frame spacing, and Side shell plate. Ship design optimisation is then carried out by incorporating regression equations from Minitab software into the Non-dominated Sorting Genetic Algorithm II (NSGA-II), which is managed using Python software (PyCharm Community Editon 2020.3.1). This optimisation process yields a significant 10% reduction in both ship weight and production costs compared to the previous design, achieved through prudent adjustments in plate thickness, web frame positioning, and stiffener arrangement. The optimally designed midship section undergoes rigorous validation to ensure conformity with industry standards and classification society regulations. Necessary adjustments to inner bottom plates and double bottom side girders are made to meet these stringent requirements. This research offers a comprehensive framework for the structural optimisation of ship hulls, potentially enhancing safety, sustainability, and competitiveness within the maritime engineering industry. [ABSTRACT FROM AUTHOR]

This study has aimed to investigate the impact of individual talent on ship captains' job satisfaction, safety performance, and safety motivation, as well as the function of safety motivation as a mediating variable. A quantitative research approach has been used for this investigation. With a sample of one hundred respondents, the population in the study has consisted of all cargo ship captains, including container ships, general cargo ships, bulk carriers, and tankers whose ships stopped at the Tanjung Perak port of Surabaya, Indonesia. Purposive sampling is a sampling method. This study has used SMART PLS software and Partial Least Square strategy for inferential data analysis. The findings show that job satisfaction, safety performance, and safety motivation are significantly influenced by individual aptitude. Safety motivation affects job satisfaction, but safety motivation has no effect on safety performance. The study has also found out that safety motivation variables can mediate the relationship between individual talent and job satisfaction through safety motivation. However, safety motivation is not able to mediate the relationship between individual aptitude and safety performance. The implication of management is that safety motivation plays an important role for cargo ship captains, besides that job satisfaction is also considered to achieve safety performance. [ABSTRACT FROM AUTHOR]

The occurrence of accidents, chemical fuels and cargo carried by ships, garbage, and oil spills from ships because of marine transportation activities causes environmental problems whose impact can threaten environmental sustainability. Studies have shown that the role of the human factor is 70-80% in the occurrence of environmental sustainability threats. Some literature on green human resource management has examined that the role of green competencies is the main requirement in improving one's performance in the environmental field. In order to support sustainable shipping management, there needs to be a study on green competencies. However, studies on construct development and validation of green competencies measurements in the shipping industry have not been widely conducted. This study aims to develop a scale of green competencies measuring instruments referring to the view of maintaining the marine environment in the shipping industry. Empirical studies have been conducted based on a quantitative approach, with survey methods conducted on 333 crew (seafarers) who have been employees in the shipping industry. The analysis of green competency measuring instrument development model has been done by using Confirmatory Factor Analysis (CFA) by SEM PLS 4.0 software. The findings of this study show that green competencies is a multidimensional reflective scale consisting of dimensions of green knowledge, green skills, green attitude, green awareness and green ability that have been tested for validity and reliability. The implication of these findings is to contribute to a literature review on green competencies, especially in the shipping industry. In addition, the results of the analysis on the green competencies construct model can be used as the basis for the preparation of a green competencies model for the benefit of green human resource management in the shipping industry. [ABSTRACT FROM AUTHOR]

Alternative fuels of low or zero carbon content can decarbonise the shipping operations. This study aims at assessing the lifetime environmental-economic sustainability of ammonia and hydrogen, as alternatives to diesel fuel for short sea shipping cargo vessels. A model is employed to calculate key performance indicators representing the lifetime financial sustainability and environmental footprint of the case ship using a realistic operating profile and considering several scenarios with different diesel substitution rates. Scenarios meeting the carbon emissions reduction targets set by the International Maritime Organisation (IMO) for 2030 are identified, whereas policy measures for their implementation including the emissions taxation are discussed. The derived results demonstrate that the future implementation of carbon emissions taxation in the ranges of 136–965 €/t for hydrogen and 356–2647 €/t for ammonia can support these fuels financial sustainability in shipping. This study provides insights for adopting zero-carbon fuels, and as such impacts the de-risking of shipping decarbonisation. [Display omitted] • Economic and environmental sustainability assessment of diesel fuel substitution. • Scenarios for addressing IMO decarbonisation targets with ammonia and hydrogen. • Hydrogen fuel prices below 700 €/t provide economic sustainability. • Carbon tax of 136 €/t for H 2 and 261 €/t for NH 3 is required to reach baseline NPV. • H 2 substitution scenarios over performs ammonia in economic sustainability. [ABSTRACT FROM AUTHOR]