Knowledge

Keyword: Sustainability

paper

Ship speed optimization: Concepts, models and combined speed-routing scenarios

Psaraftis, Harilaos N.; Kontovas, Christos A.

The purpose of this paper is to clarify some important issues as regards ship speed optimization at the operational level and develop models that optimize ship speed for a spectrum of routing scenarios in a single ship setting. The paper’s main contribution is the incorporation of those fundamental parameters and other considerations that weigh heavily in a ship owner’s or charterer’s speed decision and in his routing decision, wherever relevant. Various examples are given so as to illustrate the properties of the optimal solution and the various trade-offs that are involved.

Transportation Research Part C: Emerging Technologies, Volume 44 / 2014
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paper

Short-term discard survival and catch-related trauma in European plaice (Pleuronectes platessa) caught in the Baltic Sea by Danish seine during summer

Rasmus Ern, Andreas Faber & Niels Madsen

Danish seine is an active fishing gear targeting demersal species, such as European plaice (Pleuronectes platessa, hencefort referred as plaice), a commercially important fish species in the North Sea, Skagerrak, Kattegat, and Baltic Sea. Danish seining is a relevant fishery in relation to exemption from the European Union landing obligation. Trials were conducted from a commercial fishing vessel during the summer with high air temperatures and sea salinity and marked salinity and temperature gradients (pycnocline). Video equipment was used to observe fish entering the seine. Captured fish were individually tagged and housed in livewells for ten days to observe short-term survival. Reflex impairments and external injuries were assessed after capture and at the end of the observation periods using reflex action mortality predictor (RAMP) and catch-damage index (CDI) methodologies. We found that plaice entered the seine late in the towing process and that 87 % of the assessed fish survived, after 10 days of observation. There was a significant difference in short-term survival curves for fish that had been subjected to more than 30 min of on-deck during the catch-sorting process relative to those that had remained on deck for 30 min or less. The association between the time on deck and RAMP scores after capture was also significant. External injuries were primarily minor bruises, fin fraying, and net marks and changed little from after capturing to the end of the observation period.

Fisheries Research / 2025
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book

Identification of Success Factors for Green Shipping with Measurement of Greenness Based on ANP and ISM

Ren, Jingzheng; Lützen, Marie

Green shipping as an emerging concept which aims to mitigate the negative environmental impacts caused by shipping activities has received more and more attentions recently. However, there is a gap in knowledge how to take the efficacious measures, which makes it difficult for the stakeholders of shipping activities to promote green shipping. In order to fill this gap, this chapter proposed a generic methodology for establishing a criterion evaluation system for greenness assessment of shipping, including the identification of the success factors, the development of some strategic measures, and the analysis of the measures for enhancing the greenness of shipping. A criterion evaluation system which consists of multiple criteria in five aspects including: technological aspect, economic aspect, environmental aspect, social aspect, and managerial aspect has been firstly established. Subsequently, Analytic Network Process (ANP) has been employed to determine the relative importance of these factors in green shipping with the consideration of the interdependences and interactions among these criteria for evaluating the greenness of shipping, and they have been ranked from the most important to the least. Accordingly, the key success factors for green shipping have been obtained. Then, some strategic measures for helping the stakeholders enhance the greenness of shipping have been proposed. Finally, Interpretative Structuring Modeling (ISM) has been employed to analyze the cause-effect relationships among these measures and the features of these measures.

Book chapter in P. T-W. Lee, & Z. Yang (Eds.), International Series in Operations Research and Management Science / 2017
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paper

Ten years of climate change adaptation in Greenlandic fisheries: key observations from local ecological knowledge

Rikke Becker Jacobsen, Sun Cole Seeberg Dyremose, Kristen Ounanian & Jesper Raakjær

This article reviews and examines the most significant climate-change-related impacts and adaptation from the perspective of stakeholders in Greenlandic fisheries. The study was constructed as a comprehensive, multi-site, bottom-up case study around Greenlandic fisheries (south-north/offshore-inshore), where interviews and workshops with Greenlandic fishermen and stakeholders have communicated their observations of fishery changes associated with changes in the marine environment within the last decade. Key observations include: changes in sea ice cover; increased abundance of known species in North Greenland; fish species relocation and periodic absences in coastal systems; a northward movement of the shrimp fishery; new and unprecedented bycatch issues; and new fisheries. Stakeholder knowledge acknowledges the capacity of both offshore and coastal fisheries to adapt to changing seasonality and distribution. Factory capacity and decision-making as well as bycatch legislation have been identified as the most critical bottlenecks for (re)diversifying fisheries and increasing the value of the locally available resources.

Climate Research / 2023
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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
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Collaborating for Green: Towards an Ecosystem Configuration of the Maritime Industry

Rosa Maria Klöser, Leonardo Santiago

Reduction of carbon emissions is a societal challenge that demands concerted efforts. The maritime industry is no exception. This paper takes an ecosystem perspective and considers the question of how to enact the green transition of the maritime industry and explore the barriers and enablers of that goal. To this end, we conduct an exploratory case-study to investigate the maritime value chain by focusing on 9 major stakeholders and conducting more than 20 interviews. Our study reveals four continuous enablers and two essential enablers to establishing a functional green maritime ecosystem.

The 29th EurOMA International Annual Conference 2022: Brilliance in Resilience: Operations and Supply Chain Management’s Role in Achieving a Sustainable Future - Berlin, Germany / 2022
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paper

Development of an advanced, efficient and green intermodal system with autonomous inland and short sea shipping – AEGIS

S. Krause*, L. Wurzler, O. E. Mørkrid, K. Fjørtoft, H. N. Psaraftis, M. R. Vilanova, T. Zis, N. F. Coelho, J. Van Tatenhove, J. Raakjær, K. Kloch, M. B. Billesø, J. N. Kristiansen

The European maritime transport policy recognizes the importance of the waterborne transport systems as key elements for sustainable growth in Europe. A major goal is to transfer more than 50% of road transport to rail or waterways within 2050. To meet this challenge waterway transport needs to get more attractive and overcome its disadvantages. Therefore, it is necessary to develop new knowledge and technology and find a completely new approach to short sea and inland waterways shipping. A key element in this is automation of ships, ports and administrative tasks aligned to requirements of different European regions. One main goal in the AEGIS project is to increase the efficiency of the waterways transport with the use of higher degrees of automation corresponding with new and smaller ship types to reduce costs and secure higher frequency by feeders and provide multimodal green logistics solutions combining short sea shipping with rail and road transport.

Journal of Physics: Conference Series / 2022
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paper

Closed-Loop Systems to Circular Economy: A Pathway to Environmental Sustainability?

Sami Kara*, Michael Hauschild, John Sutherland, Tim McAloone

The global society faces an existential threat if it fails to meet current and future material needs of its populations, while staying within the carrying capacity of our planet. An approach that has been put forwards to address this complex challenge is to aim to close our society's material flows through introduction of a Circular Economy (CE). This paper provides an extensive literature review to understand the evolution of material circularity concepts and strategies, and their potential for increasing material efficiency and reduce environmental impacts towards meeting the material needs of our societies in an environmentally sustainable manner. Based on the review it can be concluded that CE may have a strong potential to help address the challenge. However, this requires broadening the focus of CE from technical and economical to political and socio-cultural dimensions, adopting a whole-systems approach, aiming to redesign economic and social relations to not just reduce the impact humanity has on the environment but actually achieve a balance in human-nature relations with a planetary boundary thinking. Pursuing purely technical and economic avenues to implement CE for increasing material circulation and sustainable growth on the foundation of our current linear economic system, will not achieve its full potential. It will not be sustainable but continue to produce the challenges that we currently have.

C I R P Annals / 2022
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Towards a more inclusive, systemic and multi-regulatory Blue Economy: the case of offshore wind energy

Sandra Cassotta

Climate change is affecting the oceans with increased sea levels, ocean acidification and extreme weather affecting coastal ecosystems. This necessitates a new model for climate and marine law, because existing law and policy are insufficient to tackle adaptation and mitigation impacts upon the marine environment. Presently, we do not know what it takes to integrate and balance climate legislation and governance when faced with unknown problems. The concept of Blue Economy is new and originates from the United Nations Conference on Sustainable Development. This chapter explores how one can best build new knowledge that can integrate climate law and marine governance. It does so by proposing the creation of a nexus between ecosystem-based regulations and marine spatial planning in order to create a new paradigm for effective and inclusive Blue Economy, using a systemic multi-regulatory framework (Global, Regional and National).

Edward Elgar Publishing / 2023
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paper

Sustainable and Just Deep-Sea Mining for the Energy Green Transition: A conundrum without Legal, Governance or Technological Solutions. The Case of the EU

Sandra Cassotta & Michael Evan Goodsite

In January 2023 the International Seabed Authority (ISA), an intergovernmental organization established under the 1982 UN Convention on the Law of the Sea (UNCLOS) granted already thirty contracts for exploration of Deep Seabed Mining, but exploitation has not started yet because ISA has not finalized its regulations, expected in 2025. This article intends to address to what extent is the current deep Seabed mining regime factoring risks and uncertainties in a just and sustainable manner in the current legal framework on environmental liability embedded in the green energy transition's processes with the EU as case study and inquiry if there are baseline or best practice to learn from. It unravels which type of precautionary approach fits and is just. Deep Seabed Mining is also a social justice, ethical dilemma demanding equitable and shared solutions to the benefit of current and future generations because activities of this kind can destroy ecosystems that can take decades to regenerate, if not causing irreversible damage. Law and technology, but also technology will be crucial as new methods guaranteeing an "environmentally benign Deep Seabed Mining" will determine how liability law will be shaped.

European Energy and Environmental Law Review / 2023
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