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Reflections on the Environmental Impact Assessment in the BBNJ Agreement: Its Implications for the Conservation of Biological Diversity in the Marine Arctic beyond National Jurisdiction

Tanaka, Yoshifumi

The BBNJ Agreement will affect legal frameworks for the conservation of marine biological diversity in various regions of the world ocean and the marine Arctic is no exception. As biological diversity in the marine Arctic is particularly vulnerable, the implications of the BBNJ Agreement for the conservation of biological diversity in the marine Arctic deserves serious consideration. Of particular note is the procedure for an environmental impact assessment (EIA). Given that damage to the environment may be irreversible, it is a prerequisite to conduct an EIA before authorizing planned activities, with a view to preventing environmental harm. An EIA constitutes a crucial element in the conservation of the marine environment, including biological diversity. Hence, this article examines the potential implications of the procedure for an EIA as set out under the BBNJ Agreement for the conservation of biological diversity in the marine Arctic beyond national jurisdiction.

Ocean Development and International Law / 2024
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Effect of wave–current interaction on gap resonance between side-by-side barges

Yunfeng Ding, Jens Honoré Walther, Yanlin Shao

We investigate piston-mode fluid resonance within the narrow gap formed by two identical fixed barges in a side-by-side configuration, utilizing a two-dimensional fully nonlinear numerical wave tank. The focus is on examining the effects of uniform and shear currents. Under ‘wave+uniform-current’ conditions, a certain current speed is identified, beyond which the gap resonance reduces dramatically and monotonically with the current speed. This reduction is attributed to a stronger increase in damping compared to wave excitation, qualitatively explained by a linearized massless damping lid model. Furthermore, we study the effects of waves propagating on shear currents, maintaining an identical ambient current speed at the gap depth. Complementary to previous studies on this topic, our study reveals that the velocity profile of the studied shear current has an insignificant effect on the resonant gap amplitudes. The ambient current velocity at the gap depth is a more important key parameter to consider when assessing wave-induced gap responses, leading to a non-negligible increase in the resonant gap response. Consequently, disregarding the influence of currents in engineering practices is not a conservative approach.

Applied Ocean Research / 2024
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Monitoring hydrodynamic vessel performance by incremental machine learning using in-service data

Malte Mittendorf, Ulrik Dam Nielsen, Ditte Gundermann

An adaptive machine learning framework is established for an implicit determination of the performance degradation of a ship due to marine growth, i.e., biofouling. The framework is applied in a case study considering telemetry data of a cruise ship operating predominantly in the Caribbean Sea. The dataset encompasses seven years including three dry-docking intervals and several in-water cleaning events. The COVID-19 period receives special focus due to the drastic change in the operational profile. A main outcome of the study is a comparison of the derived performance estimate to the corresponding results of the industry standard ISO 19030. Additional aspects of the present study include the use of special regularization techniques for incremental machine learning and the increase of transparency through the implementation of prediction intervals indicating model uncertainty. Overall, it is found that the developed machine learning framework shows good agreement with the industry standard underlining its plausibility.

Ship Technology Research / 2024
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Anti-piracy lessons from the Seychelles

Christian Bueger, Ryan Adeline, Brendon J. Cannon

The success of the Seychelles Coast Guard shows how regional states, however tiny, can play an outsized role not only in countering piracy but also in maritime security in general. By taking quick and sharp action against malicious actors, small states can make a major contribution to regional maritime security. To stop the ominous return of piracy and address other maritime crimes like illegal fishing, smuggling, and pollution crimes across the world’s oceans, the contributions of small states will be crucial. Drawing on the Seychelles example, small states should overcome the sea blindness that pervades in many governments, recognize the sustainable development benefits from the blue economy, and understand security at sea as a political priority, while making efficient use of external security assistance.

War on the Rocks / 2024
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Impact of endogenous learning curves on maritime transition pathways

Sebastian Franz*, Rasmus Bramstoft

The maritime industry is a crucial hard-to-abate sector that is expected to depend on high-energy density renewable liquid fuels in the future. Traditionally, decarbonization pathways have been assessed assuming exogenous cost trajectories for renewable liquid fuels based on an exogenous learning curve. While past studies have looked at the impact of endogenizing learning curves for a specific technology utilizing linear approximation, a fully endogenous direct non-linear implementation of learning curves in a detailed sectoral model (maritime industry) that explores dynamics concerning sensitive parameters does not yet exist. Here, we apply an open-source optimization model for decarbonizing the maritime industry and further develop the model by encompassing a nonconvex mixed-integer quadratically constrained programming approach to analyze the impact of endogenized learning curves for renewable fuel costs following an experience curve approach. We find that global greenhouse gas emissions are significantly lower (up to 25% over a 30 year horizon) when utilizing endogenously modeled prices for renewable fuels compared to commonly used exogenous learning frameworks. Furthermore, we find that conventional modeling approaches overestimate the cost of climate mitigation, which can have significant policy implication related to carbon pricing and fuel efficiency requirements. In a broader context, this emphasizes the potential opportunities that can be achieved if policymakers and companies accelerate investments that drive down the costs of renewable technologies efficiently and thus trigger endogenous experience-based learning in real life.

Environmental Research Letters / 2024
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Identification of Ships in Satellite Images

Peder Heiselberg, Hasse B. Pedersen, Kristian A. Sorensen, Henning Heiselberg

Satellite imagery has become a fundamental part for maritime monitoring and safety. Correctly estimating a ship's identity is a vital tool. We present a method based on facial recognition for identifying ships in satellite images. A large ship dataset is constructed from Sentinel-2 multispectral images and annotated by matching to the Automatic Identification System. Our dataset contains 7.000 unique ships, for which a total of 16.000 images are acquired. The method uses a convolutional neural network to extract a feature vector from the ship images and embed it on a hypersphere. Distances between ships can then be calculated via the embedding vectors. The network is trained using a triplet loss function, such that minimum distances are achieved for identical ships and maximum distances to different ships. Comparing a ship image to a reference set of ship images yields a set of distances. Ranking the distances provides a list of the most similar ships. The method correctly identifies a ship on average 60 % of the time as the first in the list. Larger ships are easier to identify than small ships, where the image resolution is a limitation.

IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing / 2024
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Social fidelity in cooperative virtual reality maritime training

Pernille Bjørn*, Maja Ling Han, Andrea Parezanovic, Per Larsen

Each year maritime accidents occur at sea causing human casualties. Training facilities serve to reduce the risk of human error by allowing maritime teams to train safety procedures in cooperative real-size immersive simulators. However, they are expensive and only few maritime professionals have access to such simulators. Virtual Reality (VR) can provide a digital all-immersive learning environment at a reduced cost allowing for increased access. However, a key ingredient of what makes all-immersive physical simulators effective is that they allow for multiple participants to engage in cooperative social interaction. Social interaction which allows trainees to develop skills and competencies in navigating situational awareness essential for safety training. Social interaction requires social fidelity. Moving from physical simulators into digital simulators based upon VR technology thus challenges us as HCI researchers to figure out how to design social fidelity into immersive training simulators. We explore social fidelity theoretically and technically by combining core conceptual work from CSCW research to the design experimentation of social fidelity for maritime safety training. We argue that designing for social fidelity in VR simulators requires designers to contextualize the VR experience in location, artifacts, and actors structured through dependencies in work allowing trainees to perform situational awareness, coordination, and communication which are all features of social fidelity. Further, we identify the risk of breaking the social fidelity immersion related to the intent and social state of the participants entering the simulation. Finally, we suggest that future designs of social fidelity should consider not only trainees in the design, but also the social relations created by the instructors’ guidance as part of the social fidelity immersion.

Human-Computer Interaction / 2024
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Pre-diabetes remission in lifestyle-mediated coaching of seafarers with newly diagnosed pre-diabetes

Olaf Chresten Jensen, Nailet Delgado Mujica, Maite Duque, Alejandro Martinez, Erik Haarløv, Finn Gyntelberg

Seafarers and fishers have inequity in health at work, with a higher risk of having metabolic syndrome. They are at increased risk of developing prediabetes, which can be reversed to normoglycemia based on the evidence from other industries. This study aims to educate and activate seafarers and fishermen with the support of coaches to reverse their prediabetes to stop the further development of diabetes type 2.
Methods
Random samples of seafarers and fishermen with newly diagnosed prediabetes and HbA1c levels ranging from 5.7%-6.4% from the maritime medical health examinations constitute the study population in a 16-week prediabetes coaching program. In addition to monthly Zoom meetings, they are asked to provide weekly reports via questionnaires on personal measurements and improvements in physical activity and diets.
Results
The preliminary data from 2 maritime clinics (n=405) show prevalences of prediabetes 18.8%, 36.4%, and 49.2% in the ages 20-29, 30-49, and 50+ years respectively, all p-values < 0.02. Analysis of the clinical data from the maritime health clinics and the questionnaires from the seafarers collected weekly will formulate the effect of the intervention. Summarizing data from various national prediabetes coaching fora will be the evidence base for remission of prediabetes. Conclusions A significant portion of seafarers have prediabetes with the potential to achieve remission of their pre-diabetes by eating healthy and being physically active. The goals are to lose at least 5%–7% of their starting weight, be accustomed to doing at least 150 min. of physical activity weekly, and follow a pre-diabetes-relevant dietary plan.

International Journal of Travel Medicine and Global Health / 2024
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The influence of static versus dynamic pressure distribution strategies for modelling nonlinear waves generated by ships

Jinyu Yao, Harry B. Bingham, Xinshu Zhang*

A moving static pressure distribution is commonly used to simulate a travelling ship. However, the ship movement changes the fluid velocity around the hull, inducing pressures on the hull surface that are no longer equal to the static pressure. Therefore, we introduce a dynamic pressure correction strategy, which can accurately simulate the impact of the ship movement on the hull-surface pressure and preserve the desired hull shape under both stationary and transient conditions. The strategy is applied to a high-order spectral model and used to investigate ship-induced waves and wave resistance over a both flat and variable topography. We explore various parameters in our study, including the average water depth to ship draft ratio (h(0)/d), the channel width to ship width ratio (W/B), the Froude number (Fr-0 = U/root gh(0)) and variations in bathymetric slope. Compared with experiments on a flat bottom, the numerical results with dynamic correction show better accuracy in the simulation of ship-induced waves and wave resistance than those obtained using a static pressure distribution. The correlation coefficient for wake waves between the numerical and experimental results is improved by approximately 0.25 with the dynamic correction strategy. The amplitude and wavelength of ship-induced mini-tsunamis over a variable topography are found to be reduced when employing a dynamic correction compared with a static pressure distribution, and this effect becomes more pronounced with higher Froude number. The static pressure approach is shown to allow large deformations of the desired hull shape and changes in ship volume which are responsible for the different wave patterns from the two approaches.

Journal of Fluid Mechanics / 2024
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PiracyAnalyzer: Spatial Temporal Patterns Analysis of Global Piracy Incidents

Maohan Liang, Huanhuan Li, Ryan Wen Liu, Jasmine Siu Lee Lam*, Zaili Yang

Maritime piracy incidents present significant threats to maritime security, resulting in material damages and jeopardizing the safety of crews. Despite the scope of the issue, existing research has not adequately explored the diverse risks and theoretical implications involved. To fill that gap, this paper aims to develop a comprehensive framework for analyzing global piracy incidents. The framework assesses risk levels and identifies patterns from spatial, temporal, and spatio-temporal dimensions, which facilitates the development of informed anti-piracy policy decisions. Firstly, the paper introduces a novel risk assessment mechanism for piracy incidents and constructs a dataset encompassing 3,716 recorded incidents from 2010 to 2021. Secondly, this study has developed a visualization and analysis framework capable of examining piracy incidents through the identification of clusters, outliers, and hot spots. Thirdly, a number of experiments are conducted on the constructed dataset to scrutinize current spatial-temporal patterns of piracy accidents. In experiments, we analyze the current trends in piracy incidents on temporal, spatial, and spatio-temporal dimensions to provide a detailed examination of piracy incidents. The paper contributes new understandings of piracy distribution and patterns, thereby enhancing the effectiveness of anti-piracy measures.

Reliability Engineering and System Safety / 2024
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