Knowledge

Media: Paper

paper

Telemedical maritime assistance over three decades in Denmark

Peter Biesenbach, Line Emilie Lilholm Laugesen, Jan Vork & Søren Kristensen

INTRODUCTION. Seafaring is associated with higher occupational hazards and health risks than shore-based work. Telemedical maritime assistance services (TMAS) provide remote specialist medical support to seafarers. In Denmark, a unified national TMAS, Radio Medical Denmark (RMD), was established in 1995. This study aimed to describe the 30-year development and clinical activity of the RMD.
METHODS. This was a single-centre retrospective cohort study of all consultations provided by the RMD from 1 September 1995 to 31 December 2024. Data were extracted from annual reports based on original medical files, with organisational information from contracts and guidelines. No identifiable patient data were collected.
RESULTS. The RMD assisted 49,999 seafarers over 30 years, with annual consultations increasing from 240 in 1995 to 4,829 in 2024. The proportion requiring disembarkation or evacuation declined from >10% at the outset to approximately 5% today. The most common diagnoses were musculoskeletal (18.8%), dermatological (14.6%) and abdominal (11.5%). Since 2014, the proportion of Danish seafarers decreased from 38% to 15.1%, while Indian and Filipino seafarers increased substantially. Merchant vessels accounted for 55.7% of contacts, predominantly in the North Sea.
CONCLUSIONS. RMD has evolved into one of Europe’s largest public TMAS providers. Centralisation within an academic emergency department, combined with structured training and research, has supported sustained growth, improved decision-making and reduced evacuation rates.
FUNDING. None.
TRIAL REGISTRATION. Not relevant.

Danish Medical Journal / 2026
Go to paper
paper

Prescription patterns in the treatment of acutely ill seafarers over a three-year observation period

Hrønn Thorsteinsdottir, Line Emilie Lilholm Laugesen, Jan Vork, Kimmo Herttua, Lisa Loloma Froholdt, Peter Biesenbach

Background: The provision of healthcare for seafarers is challenging due to their isolated working conditions and limited access to healthcare. Telemedical maritime assistance relies on pre-stocked medical chests aboard vessels. However, the contents of these medical chests are not globally standardized, and current data on prescription patterns is limited.

Material and methods: A retrospective observational cohort study was conducted, analyzing medical records from ships that received telemedical assistance between 2021 and 2023. Data were obtained from medical reports submitted by onboard medical officers and an internal medical record registry.

Results: In total, 9,458 individual patients received medical assistance, and 11,698 medications were prescribed. The mean patient age was 38.7 years (range 0–91 years), and patients aged 30–49 years were the most likely to receive medication. Merchant ships were the most common type of vessel requiring medical assistance, and they also had the highest probability for drug prescriptions. Approximately 80% of patients were prescribed medications, and patients required on average 1.24 prescriptions (range 0–6). A total of 266 individual types of medication were available for prescription. Overall, patient demographics and prescription patterns did not change over the three-year period.

Conclusions: The prescription patterns in the treatment of acutely ill seafarers are highly variable due to excessive availability of different drugs. The rare use of certain medications suggests potential inefficiencies in the stock management of medical chests, warranting further evaluation. These findings underscore the need for standardizing medical chests based on a data-driven approach. Medication use in telemedical care of seafarers is frequent but highly variable. A data-driven standardization of medical chests may improve efficiency and ensure availability of essential drugs.

International Maritime Health / 2026
Go to paper
paper

Design of a novel tower damping system for semi-submersible floating offshore wind turbines considering fatigue and ultimate limit states

Haonan Tian, Mohsen N. Soltani, Baran Yeter & Diego Eduardo Galván Pozos

This study proposes a novel tower damping system to enhance the structural performance of the NREL 5 MW semi-submersible wind turbine under operational and extreme load conditions. Environmental load data from the Norwegian MET center was analyzed to characterize the loading conditions for floating offshore wind turbines (FOWT). The probability density spectrum of sea state data was employed to identify operational load conditions. At the same time, the Inverse First-Order Reliability Method (IFORM) was used to derive the 50-year extreme sea state. Perform a fully coupled Aero-Hydro-Servo-Elastic simulation of the FOWT dynamic model with a damping system using OrcaFlex software. The results reveal that: Under operational sea states, the turbine tower-top displacement was reduced by 60–70%, and acceleration by 30–40%, enhancing tower-top stability. Under extreme loads, tower-top acceleration was reduced by 5–7%, and displacement by 6–8%. Cumulative damage assessments indicate a reduction in fatigue damage of up to 72%, with the effective fatigue life of the tower base extended by 136%. The proposed damping system significantly reduces vibration under fatigue and extreme load conditions.

Ocean Engineering / 2025
Go to paper
paper

Stepping stones as metaphor for building partnerships and co-producing knowledge in coastal transitions

janni sorensen, Kristen Ounanian, Rikke Becker Jacobsen, Josefin Ekstedt, Sunniva Midthaug Solnør, Katrina Rønningen, Sílvia Gómez, Maria Hadjimichael, Wesley Flannery, Kristina Svels, Anna Antonova, Vida Maria Daae Steiro & Madeleine Gustavsson

This paper centers local processes for co-creating transitions towards more sustainable, inclusive, and resilient coastal community development. We have conceptualized a path for change processes with phases of transition including 1. Reasons to convene; 2. Governance and participation "rules"; 3. Building knowledge together; 4. Implementation and experimentation; 5. Post-hoc reflections and assessment; 6. Transfer/reproduction of practices. Here, we focus on the first three stepping stones, which form the foundation of the collaborative process, focusing on the challenges and opportunities encountered as a pilot intervention is planned. We use a framework informed by partnership-, co-creation-, transition-, and justice literatures, to analyze data focused on establishing partnerships for ongoing co-creation of knowledge, empowering actors in the local communities, and selecting options for an intervention pilot. Conclusions relate to (a) trust and preexisting relationships, (b) what inclusion means, (c) internal power differentials, (d) preexisting tensions in the community, (e) challenges to co-creation.

Local Development & Society / 2025
Go to paper
paper

Stability Assessment of a Weak Island System Connected to Two HVDC Links

Roni Irnawan, Rian Mochamad, Sanjay K. Chaudhary & Hanchi Zhang

This paper examines the stability of a weak island namely Sumbawa-Lombok of Indonesian grid, interconnected with two infeed HVDC links facilitating 2 x 120 MW power transfer from Sumba and Flores Island. Through power flow, short circuit, small signal stability, resonance stability, and transient stability analyses, it is demonstrated that the existing infrastructure fails to support such transfer due to voltage drops, overloading, and stability limitations. Upgrading to 150 kV and its subsequent component resolves the small-signal and transient stability constraint as its grid strength is increasing. The current findings underscore that the primary limitation lies in the grid's infrastructure, not in dynamic or control constraints. The current result establishes the need for strategic grid reinforcements to support HVDC integration in weak systems and sets the stage for future research on optimizing the extent of such reinforcements.

IEEE (Institute of Electrical and Electronics Engineers) / 2025
Go to paper
paper

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
Go to paper
paper

Economic and resilience-oriented operation of coupled hydrogen-electricity energy systems at ports

Daogui Tang, Hao Tang, Chengqing Yuan, Mingwang Dong, Cesar Diaz-Londono, Gibran David Agundis-Tinajero, Josep M. Guerrero & Enrico Zio

This paper proposes an economic and resilient operation architecture for a coupled hydrogen-electricity energy system operating at port. The architecture is a multi-objective optimization problem, which includes the energy system optimal economy as the goal orientation and the optimal resilience as the goal orientation. The optimal resilience orientation looks for the best resilience performance of the port through reasonable energy management including (1) reducing the amount of electricity purchased by the port power grid from the external power grid (2) improving the energy level of electric energy storage (3) improving the energy level of hydrogen energy storage. Taking the actual coupled hydrogen-electricity energy system of Ningbo-Zhoushan Port as an example, four typical scenarios were selected according to renewable generation and load characteristics, and a comparative analysis was carried out during the oriented operation. The results show that although the resilience orientation increases the operating cost compared with the economic orientation, the four scenarios reduce the load shedding by 44.84%, 30.26%, 48.49% and 34.37% respectively when the external power grid is disconnected. The impact of changes in resilience-oriented weight coefficients and hydrogen price on system resilience performance was investigated to provide more references for decision makers.

Applied Energy / 2025
Go to paper
paper

A hierarchical multi-objective co-optimization framework for sizing and energy management of coupled hydrogen-electricity energy storage systems at ports

Pingxu Ge, Daogui Tang, Yuji Yuan, Josep M. Guerrero & Enrico Zio

Hydrogen-electricity integrated multi-energy systems are promising approaches to reduce carbon emissions in ports. However, the stochastic nature of renewable energy and the imbalance between the renewable generation and load demand in ports necessitate the design of an appropriate coupled hydrogen-electricity energy storage systems (CHEESS). This paper proposes a multi-objective optimization model for CHEESS configuration in random unbalanced port integrated multi-energy systems (PIMES), aiming to minimize its life-cycle cost and carbon emissions through co-optimization of sizing and energy management. A hierarchical two-stage framework is proposed to solve the multi-objective model. The proposed optimization framework is applied to a real PIMES at the Ningbo-Zhoushan Port. The results show that the proposed method can save 10.54% of the monetary cost and 19.67% of carbon emissions over the entire life-cycle of the system. The study demonstrates that the proposed framework has the potential to generate significant economic and environmental benefits and provides a feasible solution for port authorities seeking to implement CHEESS, aiming to promote sustainability in port operations.

Applied Energy / 2025
Go to paper
paper

Extreme nonlinear ship response estimations by active learning reliability method and dimensionality reduction for ocean wave

Tomoki Takami, Masaru Kitahara, Jørgen Juncher Jensen & Sadaoki Matsui

An efficient extreme ship response prediction approach in a given short-term sea state is devised in the paper. The present approach employs an active learning reliability method, named as the active learning Kriging + Markov Chain Monte Carlo (AK-MCMC), to predict the exceedance probability of extreme ship response. Apart from that, the Karhunen-Loève (KL) expansion of stochastic ocean wave is adopted to reduce the number of stochastic variables and to expedite the AK-MCMC computations. Weakly and strongly nonlinear vertical bending moments (VBMs) in a container ship, where the former only accounts for the nonlinearities in the hydrostatic and Froude-Krylov forces, while the latter also accounts for the nonlinearities in the radiation and diffraction forces together with slamming and hydroelastic effects, are studied to demonstrate the efficiency and accuracy of the present approach. The nonlinear strip theory is used for time domain VBM computations. Validation and comparison against the crude Monte Carlo Simulation (MCS) and the First Order Reliability Method (FORM) are made. The present approach demonstrates superior efficiency and accuracy compared to FORM. Moreover, methods for estimating the Mean-out-crossing rate of VBM based on reliability indices derived from the present approach are proposed and are validated against long-time numerical simulations.

Marine Structures / 2025
Go to paper
paper

Djibouti first: Local agency and the geopolitics of ports in infrastructure-led development

Jessica Larsen

Infrastructure-led development is driving geopolitical agendas in the Global South, and Djibouti is a case in point. Strategically situated in the Horn of Africa, Djibouti's seaports and related infrastructure have been modernized through foreign investments to serve international trade and growing African hinterlands. Scholarship often posits foreign logistics investors as hegemons driven by geopolitical interests, and host states as passive recipients. This paper questions such claims. It examines the relationship between "hegemon" and "host state" from the perspective of the latter, in this case the Djibouti government's interactions with Emirati and Chinese infrastructure companies. Methodologically, the analysis is based on interviews, secondary data and document analysis. It applies a conflict-sensitive controversies approach from critical logistics studies to trace contestation over authority in Djibouti's logistics sector. It shows how Djibouti's government applies various strategies (discursive, legal and political) to exercise agency in its logistics sector. The paper concludes that the geopolitics of infrastructure-led development is a reciprocal effort that goes beyond conventional logics of hegemons imposing on host states.

Journal of Eastern African Studies / 2025
Go to paper