Spatial tools to calculate cumulative impact assessments on the environment (CIA) are important contributors to the implementation of an ecosystem-based approach to maritime spatial planning (MSP). Ecosystem dynamics are increasingly important to understand as the activities and pressures in marine areas increase. Results from the application of a new training set for the CIA tool MYTILUS, developed in capacity-building MSP projects for active learning environments, illustrate important points on how the CIA method can be used in systematic scenario design. The feedback from its use in an online PhD course outlines how the training set successfully enables researchers from different disciplines and different parts of the world to meet the CIA approach with such interest and understanding that it enables them to highlight the strengths as well as the shortcomings of the tool interface, tool capabilities, and CIA method, even when none of these researchers are CIA experts. These promising results are presented in this paper and advocate for the increasing use of MYTILUS and similar CIA tools in MSP stakeholder sessions where no preliminary CIA expertise can be expected. The key strengths and challenges of training CIA with MYTILUS are discussed to point out focus points for how to make its approaches increasingly fit for participatory and decision-making processes in MSP to utilize its promising abilities for supporting ecosystem-based management.
Collaborative spatial decision support tools can contribute with setups for including stakeholders into marine spatial planning (MSP) processes with the purpose of increasing trust in planning outcomes, facilitate knowledge co-creation and shared planning goals, and provide transparent, scientific, inclusive, and technical foundations for planning. A new collaborative spatial decision support setup based on the combination of functionalities from two spatial decision support tools called SEANERGY and Baltic Explorer was designed for and tested in a workshop in 2020 targeted local authorities, NGOs, and citizens in Denmark with an interest in MSP. While the setup needs further testing among a wider span of stakeholders to support a pluralistic approach, the findings illustrate promising potentials from ranking conflicts and synergies in collaborative settings to make marine activity interests spatially visible in MSP and gain an overview of opportunities for sea use multi-functionality in context-based, interactive, goal-oriented stakeholder processes. The use of a visual platform such as Baltic Explorer to systematically explore locations of marine uses was positively evaluated to facilitate the workshop conflict-synergy discussions. Challenges relate to how to deal with disagreements on conflict-synergy scores and the subjectivity of opinions, but the demonstrated flexible, quick, transparent way to test the sensitivity of spatial patterns to differences in input conflict-synergy scores is found to provide a promising setup for including stakeholder opinions through collaborative settings, a setup adjustable to supplementary large-scale, individual, more representative surveys as well.
Life depends on healthy oceans that provide ecosystem services (ES) to humans, including provisioning, regulating, supporting, and cultural ES (Kovalenko et al., 2023). However, biodiversity, habitats, and the delivery of marine ES and resources are increasingly threatened by growing human activities in the oceans (Worm et al., 2006). Blue-growth activities, such as shipping and energy, eutrophication, and climate change represent major pressures that affect marine ecosystems (Halpern et al., 2008; Ehlers, 2016). Over the past two decades, increasing scientific attention has focused on the need to preserve and restore healthy marine waters and their role in adapting to climate change (Santos et al., 2020). This challenge calls for holistic approaches that advance our knowledge. Within the contributions to this Research Topic (see Figure 1), three themes are central to driving further research to expand our understanding in this interdisciplinary field.
Denne afhandling omhandler steds- og mobilitetsudfordringer samt byudviklingspotentialer
for det, der i afhandlingen betegnes ’transit- og levebyer’. Provins- og havnebyen Hirtshals,
beliggende på Danmarks nordlige vestkyst, fungerer i afhandlingen som gennemgående case,
der overordnet illustrerer, hvordan et sted kan være i vækst og tilbagegang på samme tid.
Afhandlingens problemfelt indskriver sig i en samfundsmæssig kontekst af øget mobilitet samt
centralisering og yderområder, og påpeger provinsbyens rolle som et lokalt knudepunkt samt
havnebyens rolle som et nationalt knudepunkt. Således er casen også et eksempel på et stærkt
mobilitetspåvirket sted i det, jeg benævner ’Gennemfartsdanmark’, hvor mange mennesker
rejser igennem, men kun få gør ophold. Afhandlingen sætter spørgsmålstegn ved, om et sådan
sted overhovedet opfattes som en by med et godt og attraktivt byliv, eller kun som et transit-hub.
Havnen i Hirtshals er et logistisk knudepunkt for både mennesker og gods, med gode
forbindelser til bl.a. Norge, Island, Færøerne og Storbritannien, og med direkte adgang til den
europæiske motorvejskorridor. Der investeres i Hirtshals i store infrastrukturprojekter for at
understøtte havnens aktiviteter og virke, som genererer arbejdspladser og et stigende antal
gennemrejsende erhvervschauffører og turister. Samtidig falder befolkningstallet hastigt: fra mere
end 7.000 indbyggere til mindre end 6.000 indbyggere de sidste 15 år. Afhandlingen adresserer
og udfordrer på den baggrund den i udgangspunktet ofte fremførte samfundsmæssige diskurs,
at øget mobilitet skaber vækst og fremgang for byer per se!
Ph.d.-projektet er opbygget omkring et overvejende kvalitativt forskningsdesign, og søger
derved at komme frem til en dybere forståelse af, hvad der ligger bag det statistiske materiale
om befolknings- og erhvervsudvikling i Hirtshals. Videnskabsteoretisk bygger afhandlingen
på en pragmatisk forståelsesramme, der tilskynder at lade empirien være omdrejningspunkt
for forskning, mens teorier og metoder anses som praktiske værktøjer i vidensproduktionen.
Forskningsprojektet undersøger empirisk forholdet mellem vækst i infrastrukturprojekter,
erhverv, gods og rejsende og tilbagegang i befolkningstal, offentlige funktioner og det byggede
miljø. Dette belyses gennem casestudiet, der er baseret på en række forskellige praktiske metoder,
herunder dokumentanalyser, interviews, spørgeskemaundersøgelser, registerdata og fysiskrumlige stedsanalyser. Blandingen af metoder muliggør at studere casen fra mange vinkler, og
belyse Hirtshals’ fortid og nutid samt fremtidsperspektiver.
Afhandlingen skaber en forståelse omkring casens stedslige og mobilitetsrelaterede
udfordringer, kvaliteter og potentialer, for derved at kvalificere en række byudviklingsperspektiver.
Teoretisk er forskningsprojektet funderet i begreberne sted og mobilitet, og udvikler derudfra
en terminologi omkring ‘transitbyer’ og ‘levebyer’. Den klassiske stedsteori og konventionelle
transportforskning udfordres gennem en relationel og mobilitetsorienteret stedsforståelse, der
bruges til at analysere casen. En relationel og mobilitetsorienteret stedsforståelse betyder, at sted
konkret må opfattes og defineres som en relation mellem fysik og geografi, mobilitet og sociale
sammenhænge, historie og betydning.
På baggrund af afhandlingen kan det konkluderes, at Hirtshals hverken kan forstås isoleret
som transitby eller isoleret som leveby, men at Hirtshals netop består, fungerer og eksisterer i
kraft af begge dele. Derfor peger afhandlingen på, at det er vigtigt i forhold til byplanlægning i
Hirtshals og andre stærkt mobilitetspåvirkede byer og steder, at tænke kvaliteterne ved transitby
og leveby sammen. På baggrund af casestudiet udvikles en relationel og mobilitetsorienteret
stedsstrategi med generelle anbefalinger for Hirtshals og andre transit- og levebyer.
Det er ønsket med denne afhandling at kondensere en række læringspunkter fra
Hirtshals, der kan være medvirkende til at gøre en forskel i praksis. Casestudiets resultater er i
udgangspunktet kontekstafhængige, men rummer samtidig almengyldige kvaliteter. Studiet af
Hirtshals kan således generere værdifuld viden til planlægningen i byer, der som Hirtshals er
stærkt mobilitetspåvirkede, og hvor der kan stilles spørgsmålstegn ved, om den pågældende by
overvejende er en transit- eller leveby?
The power system of an all-electric ship (AES) establishes an independent microgrid using the distributed energy resources, energy storage devices, and power electronic converters. As a hybrid energy system (HES), the power system of an AES works as a unified system where each part can affect the reliability of the other parts. The systemic reliability centered maintenance (SRCM), which efficiently enhances the reliability and safety of the AES by identifying optimal maintenance tasks of the AES, is considered in this article to apply to the entire system. In order to calculate the reliability and optimal maintenance schedule, the Markov process and Enhanced JAYA (EJAYA) are utilized. A layer of protection analysis (LOPA), which is a risk management technique, is adopted to assess the safety of the system. A hybrid molten carbonate fuel cell, photovoltaic (PV), and lithium-ion battery are considered as energy sources of the AES. Based on two common standards, DNVGL-ST-0033 and DNVGL-ST-0373, the suggested maintenance planning method can be used in industrial applications. Eventually, in order to validate the proposed method, a model-in-the-loop real-time simulation using dSPACE is carried out. The obtained results show the applicability and efficiency of the proposed method for improving reliability and safety.
This paper examines the statistical properties and the quality of the speed through water (STW) measurement based on data extracted from almost 200 container ships of Maersk Line’s fleet for 3 years of operation. The analysis uses high-frequency sensor data along with additional data sources derived from external providers. The interest of the study has its background in the accuracy of STW measurement as the most important parameter in the assessment of a ship’s performance analysis. The paper contains a thorough analysis of the measurements assumed to be related with the STW error, along with a descriptive decomposition of the main variables by sea region including sea state, vessel class, vessel IMO number and manufacturer of the speed-log installed in each ship. The paper suggests a semi-empirical method using a threshold to identify potential error in a ship’s STW measurement. The study revealed that the sea region is the most influential factor for the STW accuracy and that 26% of the ships of the dataset’s fleet warrant further investigation.
Maintaining the condition of a vessel and its equipment guarantees the scheduled completion of voyages and the safety of the crew.
This paper presents condition monitoring techniques for early detection of faults related to piston rings in remote cylinders of two-stroke marine diesel engines. Operational sensor data from the main engine of a container ship are provided by a shipping company.
A graphical approach complimented by correlation heatmaps and feature importance from gradient boosting trees are used for feature selection. Support Vector Machine, Random Forest and Extreme Gradient Boosting Trees are tested for residual generation from the nominal behavior.
The residual time series gives a good indication of the degradation of the system and can be used for alarm raising under strict rules. It is proven that the proposed method could alert the engine crew of a change in the condition of the piston rings much earlier than existing methods.
The European Commission recently proposed requirements for the production of renewable fuels as these are required to decarbonize the hard-to-electrify parts of the industrial and heavy transport sectors. Power-to-X (P2X) energy hubs enable efficient synergies between energy infrastructures, production facilities, and storage options. In this study, we explore the optimal operation of an energy hub by leveraging the flexibility of P2X, including hydrogen, methanol, and ammonia synthesizers by analyzing potential revenue streams such as the day-ahead and ancillary services markets. We propose EnerHub2X, a mixed-integer linear program that maximizes the hub’s profit based on current market prices, considering the technical constraints of P2X, such as unit commitment and non-linear efficiencies. We investigate a representative Danish energy hub and find that without price incentives, it mainly sells renewable electricity and produces compressed hydrogen. A sufficient amount of renewable ammonia and methanol is only produced by adding a price premium of about 50% (0.16 €/kg) to the conventional fuel prices. To utilize production efficiently, on-site renewable energy sources and P2X must be carefully aligned. We show that renewable power purchase agreements can provide flexibility while complying with the rules set by the European Commission.
This paper presents the flexible containership loading problem for seaport container terminals. The integrated management of loading operations, planning of the transport vehicles to use and their scheduling is what we define as the Flexible Ship Loading Problem (FSLP). The flexibility comes from a cooperative agreement between the terminal operator and the liner shipping company, specifying that the terminal has the right to decide which specific container to load for each slot obeying the class-based stowage plan received from the liner. We formulate a mathematical model for the problem. Then we present various modelling enhancements and a mathematical model to obtain strong lower bounds. We also propose a heuristic algorithm to solve the problem. It is shown that enhancements improve the performance of formulation significantly, and the heuristic efficiently generates high-quality solutions. Results also point out that substantial cost savings can be achieved by integrating the ship loading operations.
Most of the operational problems in container terminals are strongly interconnected. In this paper, we study the integrated Berth Allocation and Quay Crane Assignment Problem in seaport container terminals. We will extend the current state-of-the-art by proposing novel set partitioning models. To improve the performance of the set partitioning formulations, a number of variable reduction techniques are proposed. Furthermore, we analyze the effects of different discretization schemes and the impact of using a time-variant/invariant quay crane allocation policy. Computational experiments show that the proposed models significantly improve the benchmark solutions of the current state-of-art optimal approaches.