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The Importance of Connected Ocean Monitoring Knowledge Systems and Communities

Kaiser, Brooks A.; Hoeberechts, Maia; Maxwell, Kimberley H.; Eerkes-Medrano,Laura; Hilmi, Nathalie; Safa, Alain; Horbel, Chris; Juniper, S. Kim; Roughan, Moninya; Lowen, Nicholas Theux; Short, Katherine; Paruru, Danny

Ocean monitoring will improve outcomes if ways of knowing and priorities from a range of interest groups are successfully integrated. Coastal Indigenous communities hold unique knowledge of the ocean gathered through many generations of inter-dependent living with marine ecosystems. Experiences and observations from living within that system have generated ongoing local and traditional ecological knowledge (LEK and TEK) and Indigenous knowledge (IK) upon which localized sustainable management strategies have been based. Consequently, a comprehensive approach to ocean monitoring should connect academic practices (“science”) and local community and Indigenous practices, encompassing “TEK, LEK, and IK.” This paper recommends research approaches and methods for connecting scientists, local communities, and IK holders and their respective knowledge systems, and priorities, to help improve marine ecosystem management. Case studies from Canada and New Zealand (NZ) highlight the emerging recognition of IK systems in natural resource management, policy and economic development. The in-depth case studies from Ocean Networks Canada (ONC) and the new Moana Project, NZ highlight real-world experiences connecting IK with scientific monitoring programs. Trial-tested recommendations for successful collaboration include practices for two-way knowledge sharing between scientists and communities, co-development of funding proposals, project plans and educational resources, mutually agreed installation of monitoring equipment, and ongoing sharing of data and research results. We recommend that future ocean monitoring research be conducted using cross-cultural and/or transdisciplinary approaches. Vast oceans and relatively limited monitoring data coupled with the urgency of a changing climate emphasize the need for all eyes possible providing new data and insights. Community members and ocean monitoring scientists in joint research teams are essential for increasing ocean information using diverse methods compared with previous scientific research. Research partnerships can also ensure impactful outcomes through improved understanding of community needs and priorities.

Frontiers in Marine Science, VOLUME 6 / 2019
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The Influence of a Crown Wall on Wave Overtopping over Breakwaters

Mads Røge Eldrup, Thomas Lykke Andersen, Koen Van Doorslaer & Jentsje W. van der Meer

This paper investigates the influence of a crown wall on wave overtopping on rubble mound breakwaters. Existing data is used to modify the EurOtop overtopping formula updated by Eldrup et al. (2022) to cover the influence of the crown wall. The effect of raising the wall above the armor crest (elevated wall) or lowering the wall below the armor crest (lowered wall) is investigated. A crown wall at the armor crest level is considered as the reference case. By increasing the elevation of either the armor crest or the crown wall, overtopping is reduced and by lowering either of them, overtopping increases. The influence of the crown wall height, elevated or lowered compared to the armor crest, is not considered accurately in the present design guidelines and thus corrections are suggested. For an elevated wall, a modified crest width has been defined, to better describe the presence of the armor crest in front of the wall. For the lowered wall the effective freeboard might be taken as the average of the wall and armor freeboards. The improvement compared to existing methods is significant, especially for breakwaters with a large elevated wall. The proposed modifications to the EurOtop Manual increase the range of applicability with respect to the wall configuration.

Coastal Engineering Research Council / 2023
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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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The Influence of Temperature, H2O, and NO2 on Corrosion in CO2 Transportation Pipelines

Kenneth René Simonsen, Jacalyn Goebel, Dennis Severin Hansen & Simon Pedersen

The expansion of Carbon Capture, Utilization, and Storage (CCUS) highlights the growing need for carbon dioxide (CO2) pipeline transportation. While pure CO2 is non-corrosive, impurities such as H2O and NO2 create a corrosive environment that risks pipeline integrity. This study investigates how H2O and NO2 concentrations, along with temperature, influence corrosion under CO2 pipeline conditions. The investigation was performed in an autoclave setup emulating a linear velocity of 0.96 m/s at 100 bar and temperatures of 5 °C and 25 °C, testing X52 and GR70, and a more corrosion-resistant 9Cr alloy. The results indicated that the presence of NO2 elevated the corrosion rate compared to scenarios without. Low H2O concentration led to a corrosion rate of up to five times higher at 5 °C, compared to at 25 °C, in the presence of NO2. Low to moderate corrosion was observed for the carbon steels without NO2 and with 70 ppmv H2O at both temperatures. Reducing the H2O concentration below 70 ppmv and removing NO2, while SO2 and O2 are present, will only result in low to moderate corrosion in the carbon steel CO2 pipeline. The corrosion rate for X52 and GR70 was 0.065 mm/y and 0.016 mm/y higher or 5 and 3 times greater, respectively, at 5 °C compared to 25 °C. The study concludes that H2O should be maintained below 70 ppmv and NO2 should be eliminated to prevent severe corrosion. Emphasizing the importance of CO2 specification compliance and the need for further research into CO2 compositions that align with the specifications.

Process Safety and Environmental Protection / 2025
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The influence of the propeller loading on the thrust deduction fraction

Simone Saettone*, Bhushan Taskar, Sverre Steen, Poul Andersen

The estimation of the thrust deduction fraction is generally conducted in ideal weather conditions. However, the presence of waves considerably alters the magnitude of this propulsive coefficient. The increased load of the propeller could be the main cause for the variation of the thrust deduction fraction in realistic operating conditions. In this work, load-varying self-propulsion model-scale numerical simulations in calm water conditions for the same ship speed are performed to investigate the influence of the propeller loading on the thrust deduction fraction. The single screw model-scale KVLCC2 tanker is selected as the case study. The results reveal a non-linear inverse correlation between the thrust deduction fraction and the propeller loading. A comparison with model-testing conducted on the KVLCC2 tanker in regular head waves suggests that the propeller loading is the main factor influencing the magnitude of the thrust deduction fraction in waves for the considered case vessel.

Ship Technology Research / 2022
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The International Law of the Sea

Tanaka, Yoshifumi

This new edition has been revised and updated to provide current and comprehensive coverage of essential issues of the international law of the sea in a systematic manner. This book presents two paradigms of the law of the sea: the law of divided oceans and the law of our common ocean. It covers contemporary issues, such as protection of the marine biological diversity, marine plastic pollution, the Arctic, and impacts of climate change on the oceans. Following the clear and accessible approach of previous editions, with many illustrations and tables, The International Law of the Sea continues to help students to best understand the law of the sea.

Cambridge University Press / 2023
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The landing bond calls for a more flexible technical gear regulation in EU waters – Greater industry involvement could support development of gear modifications

Søren Qvist Eliasen, Jordan Feekings, Ludvig Krag, Tiago Veiga-Malta, Lars O. Mortensen & Clara Ulrich

Rigid fisheries management frameworks often leave fishermen with limited possibilities and incentives to adjust the selectivity of their gears to the specific fishing conditions. Implementation of the landing obligation in European fisheries emphasizes fishermen's need for flexibility in which gear to use to be able to match the selectivity of the gear to the quota available. How fishermen can play an important role in facilitating a more regionalised and flexible technical regulation by actively participating in the development of gears and contributing to the scientific documentation of their selectivity is discussed. Perspectives in the proposed technical regulation for EU fisheries and the regionalization in the 2013 Common Fisheries Policy are discussed based on an analysis of the current EU technical regulation. Then a new pathway to address the problem, currently being trialled in Danish fisheries, is discussed. Throughout the article, three themes are discussed: Identifying gear needs, development and testing of gear with fishermen as central actors; how the selectivity of the gear should be documented; and opportunities for faster evaluation of new gear, following the regionalization of the technical measure regulation. The paper concludes that a more flexible system of gear development and evaluation is possible by a) involvement of fishermen in proposing gear adjustments, self-sampling and documenting results following scientific protocols and evaluation, testing a range of designs before scientific testing, and b) open for faster approval of gear use under a regionalized technical regulation regime with annual adjustments of management plans containing the technical regulation.

Marine Policy / 2019
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The liner shipping berth scheduling problem with transit times

Reinhardt, Line Blander; Plum, Christian Edinger Munk; Pisinger, David; Sigurd, Mikkel; Vial, Guillaume T. P.

In this paper speed optimization of an existing liner shipping network is solved by adjusting the port berth times. The objective is to minimize fuel consumption while retaining the customer transit times including the transhipment times. To avoid too many changes to the time table, changes of port berth times are only accepted if they lead to savings above a threshold value. Since the fuel consumption of a vessel is a non-linear convex function of the speed, it is approximated by a piecewise linear function. The developed model is solved using exact methods in less than two minutes for large instances. Computational experiments on real-size liner shipping networks are presented showing that fuels savings in the magnitude 2–10% can be obtained. The work has been carried out in collaboration with Maersk Line and the tests instances are confirmed to be representative of real-life networks.

Transportation Research Part E: Logistics and Transportation Review, Volume 86 / 2016
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The liner shipping berth scheduling problem with transit times

Reinhardt, Line Blander; Plum, Christian E.M.; Pisinger, David; Sigurd, Mikkel M.; Vial, Guillaume T.P.

In this paper speed optimization of an existing liner shipping network is solved by adjusting the port berth times. The objective is to minimize fuel consumption while retaining the customer transit times including the transhipment times. To avoid too many changes to the time table, changes of port berth times are only accepted if they lead to savings above a threshold value. Since the fuel consumption of a vessel is a non-linear convex function of the speed, it is approximated by a piecewise linear function. The developed model is solved using exact methods in less than two minutes for large instances. Computational experiments on real-size liner shipping networks are presented showing that fuels savings in the magnitude 2–10% can be obtained. The work has been carried out in collaboration with Maersk Line and the tests instances are confirmed to be representative of real-life networks.

Transportation Research Part E: Logistics and Transportation Review Volume 86 / 2016
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The liquefied natural gas infrastructure and tanker fleet sizing problem

Koza, David F.; Røpke, Stefan; Boleda Molas, Anna

We consider a strategic infrastructure and tanker fleet sizing problem in the liquefied natural gas business. The goal is to minimize long-term on-shore infrastructure and tanker investment cost combined with interrelated expected cost for operating the tanker fleet. A non-linear arc-based model and an exact solution method based on a set-partitioning formulation are developed. The latter approach allows very fast solution times. Computational results for a case study with a liner shipping company are presented, including an extensive sensitivity analysis to account for limited predictability of key parameter values, to analyze the solutions’ robustness and to derive basic decision rules.

Transportation Research Part E: Logistics and Transportation Review, Volume 99 / 2017
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