This article investigates recent reforms of the Greenland coastal fisheries in order to contribute to the general lessons on reform and policy networks in the context of a changing Arctic stakeholdership. It analyzes participation in fisheries governance decision-making by examining the emergence of discourses and policy networks that come to define the very need for reform. A policy network is identified across state ministries, powerful officials, banks and large scale industry that defined the need for fisheries reform within a 'grand reform' discourse. But inertia characterized the actual decision-making process as reform according to this 'grand reform' discourse was blocked by a combination of small-scale fishermen' informal networks and the power of the parliamentary majority. After a parliamentary shift in power the new government implemented the 'grand reform' gradually whilst new patterns of participation and exclusion emerged. In this process, the identities of the participating participants were reinterpreted to fit the new patterns of influence and participation. The article argues that fishery reform does not necessarily start with the collective recognition of a problem in marine resource use and a power-neutral process of institutional learning. Instead, it argues that fishery reform is likely to be the 'reform of somebody' and that this 'somebody' is itself a changing identity.
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.
The widespread use of software-intensive cyber systems in critical infrastructures such as ships (CyberShips) has brought huge benefits, yet it has also opened new avenues for cyber attacks to potentially disrupt operations. Cyber risk assessment plays a vital role in identifying cyber threats and vulnerabilities that can be exploited to compromise cyber systems. Understanding the nature of cyber threats and their potential risks and impact is essential to improve the security and resilience of cyber systems, and to build systems that are secure by design and better prepared to detect and mitigate cyber attacks. A number of methodologies have been proposed to carry out these analyses. This paper evaluates and compares the application of three risk assessment methodologies: system theoretic process analysis (STPA-Sec), STRIDE and CORAS for identifying threats and vulnerabilities in a CyberShip system. We specifically selected these three methodologies because they identify threats not only at the component level, but also threats or hazards caused due to the interaction between components, resulting in sets of threats identified with each methodology and relevant differences. Moreover, STPA-Sec, which is a variant of the STPA, is widely used for safety and security analysis of cyber physical systems (CPS); CORAS offers a framework to perform cyber risk assessment in a top-down approach that aligns with STPA-Sec; and STRIDE (Spoofing, Tampering, Repudiation,Information disclosure, Denial of Service, Elevation of Privilege) considers threat at the component level as well as during the interaction that is similar to STPA-Sec. As a result of this analysis, this paper highlights the pros and cons of these methodologies, illustrates areas of special applicability, and suggests that their complementary use as threats identified through STRIDE can be used as an input to CORAS and STPA-Sec to make these methods more structured.
In this research, two crucial optimization problems of berth allocation and yard assignment in the context of bulk ports are studied. We discuss how these problems are interrelated and can be combined and solved as a single large scale optimization problem. More importantly we highlight the differences in operations between bulk ports and container terminals which highlights the need to devise specific solutions for bulk ports. The objective is to minimize the total service time of vessels berthing at the port. We propose an exact solution algorithm based on a branch and price framework to solve the integrated problem. In the proposed model, the master problem is formulated as a set-partitioning problem, and subproblems to identify columns with negative reduced costs are solved using mixed integer programming. To obtain sub-optimal solutions quickly, a metaheuristic approach based on critical-shaking neighborhood search is presented. The proposed algorithms are tested and validated through numerical experiments based on instances inspired from real bulk port data. The results indicate that the algorithms can be successfully used to solve instances containing up to 40 vessels within reasonable computational time.
In transportation of goods in large container ships, shipping industries need to minimize the time spent at ports to load/unload containers. An optimal stowage of containers on board minimizes unnecessary unloading/reloading movements, while satisfying many operational constraints. We address the basic container stowage planning problem (CSPP). Different heuristics and formulations have been proposed for the CSPP, but finding an optimal stowage plan remains an open problem even for small-sized instances. We introduce a novel formulation that decomposes CSPPs into two sets of decision variables: the first defining how single container stacks evolve over time and the second modeling port-dependent constraints. Its linear relaxation is solved through stabilized column generation and with different heuristic and exact pricing algorithms. The lower bound achieved is then used to find an optimal stowage plan by solving a mixed-integer programming model. The proposed solution method outperforms the methods from the literature and can solve to optimality instances with up to 10 ports and 5,000 containers in a few minutes of computing time.
In transportation of goods in large container ships, shipping industries need to minimize the time spent at ports to load/unload containers. An optimal stowage of containers on board minimizes unnecessary unloading/reloading movements, while satisfying many operational constraints. We address the basic container stowage planning problem (CSPP). Different heuristics and formulations have been proposed for the CSPP, but finding an optimal stowage plan remains an open problem even for small-sized instances. We introduce a novel formulation that decomposes CSPPs into two sets of decision variables: the first defining how single container stacks evolve over time and the second modeling port-dependent constraints. Its linear relaxation is solved through stabilized column generation and with different heuristic and exact pricing algorithms. The lower bound achieved is then used to find an optimal stowage plan by solving a mixed-integer programming model. The proposed solution method outperforms the methods from the literature and can solve to optimality instances with up to 10 ports and 5,000 containers in a few minutes of computing time.
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.
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 purpose of this paper is to revisit speed optimization and speed reduction models for liner shipping in a multi/flexible fuel context with regards to the current ongoing speed limit debate at the International Maritime Organization (IMO). The focus is mainly on analyzing the influence of a maximum average speed limit on the optimal speeds, carbon intensity and emissions in conjunction with fleet deployment for dual fuel (DF) Neopanamax container vessels utilizing liquefied natural gas (LNG).
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.