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Do citizens value climate change mitigation over biodiversity protection? Exploring citizen support for salt marsh management
Get PDFIn December 2022, representatives adopted the Kunming-Montreal Global Biodiversity Framework (GBF). The overarching goal of the agreement is to halt biodiversity loss and restore natural ecosystems – and a much-cited target is the “30x30” target of protecting and restoring 30% of Earth by 2030. Salt marshes are highly productive coastal ecosystems relevant for both biodiversity and climate change mitigation but have experienced historical major losses and are among the habitats in need of protection and restoration. Currently, there is little knowledge about how salt marshes are valued from a societal perspective, which has important management implications. This is particularly the case in the Nordic region where awareness of these habitats is low. Using survey data from Norway, Sweden, Finland, Denmark, and Germany, this study contributes understanding how citizens value salt marshes by examining support for different management initiatives framed as contributing to the goal of either biodiversity protection or climate change mitigation. Generally, both respondents primed with information about the importance of salt marshes for biodiversity and for climate change mitigation were supportive of the management initiatives despite having little previous knowledge of salt marshes. For one initiative, respondents who were informed of the importance of salt marshes for biodiversity were slightly more likely to support the management initiative than those informed about the importance of salt marshes for climate change mitigation. Our study provides guidance for assessment of trade-offs from a human valuation perspective, thus supporting policy makers when considering arguments for salt marsh management within the context of the 30x30 targets for protected areas.publishedVersio
Rest in phase transition: Should charging habits in next generation EVs be adapted?
Get PDFNickel-rich cathode materials are a popular cathode for high energy lithium ion batteries in the current and next generation of electric vehicles. While nickel-rich cathodes offer high energy density, their cycle-life is compromised due to several factors directly related to their (de)lithiation behavior. At high state of charge the nickel-rich cathode experiences a hexagonal-hexagonal transition which is accompanied by drastic changes in the unit cell parameters. This phenomenon is detrimental for cycle-life of a battery cell. This work elucidates on the effect of storing LiNi0.8Mn0.1Co0.1O2‖Graphite cells at 95 % state of charge corresponding to the above-mentioned transition for 10 h every six cycles. The results are compared to cells cycled without a rest at high state of charge and cells cycled to 100 % state of charge. Analysis of the obtained cycling data shows that resting lithium ion cells based nickel-rich cathode based cells is detrimental leading to higher impedance growth and capacity decay than cycling to 100 % state of charge.publishedVersio
Demonstration of a low-cost solution for implementing MPC in commercial buildings with legacy equipment
Get PDFModel predictive control (MPC) approaches for HVAC systems in buildings have shown potential for significant reduction of energy use and for enabling flexible operation. However, a widespread adoption is long in coming, due to the high implementation costs and efforts, and data availability and quality. In this article, we demonstrate the implementation of a scalable, minimalistic and low-cost approach for replacing weather compensated control (WCC) with MPC in commercial buildings with legacy equipment. The concept utilizes the ventilation extract temperature as a proxy for indoor temperature to avoid excessive sensor installation and data treatment. The experiment demonstrates the applicability of the solution and indicates an energy cost saving of 33% during one month in early spring. While several points for improvement of the control algorithm are highlighted, the implementation shows robust behaviour even with up to eight hours gaps in the measurement updatespublishedVersio
Opportunities and challenges in new production systems for salmon farming in Norway—Industry perspective
Get PDFThe Norwegian salmon farming industry is characterized by an increasing technological diversity with new production systems emerging. The objective of this paper is to provide knowledge about challenges and opportunities with new production systems as perceived by industry representatives with hands-on experience. Interviews and workshops with fish farmers and suppliers illustrate that even though environmental issues concerning salmon lice, escapes, and diseases can be reduced, and in some cases solved, new challenges might arise. Semi-closed containment and land-based system concerns pertained to water quality and fish welfare, while exposed and offshore systems were more concerned about harsh conditions and their effects on fish, structures, and work operations. However, possibilities for beneficial new production strategies, the potential for a more stable production environment, and increased biosecurity are seen as important advantages. These findings provide valuable perspectives for industry, technology suppliers, and regulators moving forward.publishedVersio
A Practical Computational Model To Estimate PAH Emission From Furnaces
Get PDFDue to the large computational overhead associated with simulating the PAH chemistry, predicting the PAH emission from industrial furnaces based on detailed CFD simulations is impractical. To address the lack of tools for practical estimation of PAH emissions from furnaces, a novel approach based on CFD + 0D perfectly stirred reactor (PSR) to predict PAH generation rate is proposed in this work. This approach uses the results of the CFD simulation of the reactive flow of major process gases, based on a reaction mechanism, as the input to 0D PSR reactors (which is run on each cell in the domain) using detailed PAH chemistry.The model is used to simulate various operationally relevant scenarios like variations in the inflow (composition and velocity) of gases emanating from the charge surface and flue gas recycling levels. The model is seen to be able to capture the overall trends in the PAH emission predicted by the detailed reaction mechanism based CFD for cases simulated. As the PAH emission is chemistry driven, the choice of reaction mechanism used to CFD simulation of the major species in the proposed approach is seen to be critical as it provides a distribution of reaction intermediates relevant for PAH chemistry.publishedVersio
Utvikling av tilstandsindikatorer - aggregert indikator
Get PDFNotat beskriver kort begrunnelsen for anbefalingen om ikke å utvikle en aggregert indikator.publishedVersio
A Conceptual Model for Automation of Small Ports
Get PDFFor large ports and terminals, the loading and discharge operations have to a great extent been automated already. However, for the vast number of small ports, for instance all Norwegian ports, this large-scale automation is not possible due to the small size of the ports compared to the cost of introducing full automation. Still, these small ports are important logistics hubs in the transport system. They facilitate the shift from congested roads to the sea by allowing the goods to arrive closer to the final destination by using smaller, possibly autonomous, vessels. However, this puts pressure on the ports to facilitate reduced laytime in the port, to increase the port efficiency and to improve interoperability towards hinterland systems and terminals. For small ports, this means that manual and automated work processes need to exist side by side, and that it will be important to get an overview of which processes to automate and which will remain manual, in addition to the handling of the hand-over between humans and automation. This paper describes a conceptual model that can be used by small ports as a starting point on their way to introduce automation of their services supporting the cargo flow through the port. The model includes a description of port functions, tasks and responsibilities and use the concept of operational envelope to define the overall capabilities of the system, including both automation and human. This will be the starting point for how to structure the description of an operation centre that monitor and control the maritime terminal operations. The starting point for this work is a use case analysis performed in some small ports in Norway, and their need to optimize the utilization of their assets. The work is done as part of the AutoPort project which is a research project funded by the Norwegian Research Council (project number 337211). The goal of this work is to describe a methodology on how to identify the interface between automation and human operators when it comes to small ports and the movement of cargo through its terminals, and by this give a description on how different levels of automation can be implemented. The methodology consists of several steps, including definition of the context (big picture of the use case, actors and their roles, and communication), the scenario (port activities and processes), and the use cases including the control tasks performed by the automated systems.publishedVersio
Effect of wet clothing removal on skin temperature in subjects exposed to cold and wrapped in a vapor barrier: a human, randomized, crossover field study
Get PDFBackground: Prehospital care for cold-stressed and hypothermic patients focuses on effective insulation and rewarming. When encountering patients wearing wet clothing, rescuers can either remove the wet clothing before isolating the patient or isolate the patient using a vapor barrier. Wet clothing removal increases skin exposure but avoids the need to heat the wet clothing during rewarming. Leaving wet clothing on will avoid skin exposure but is likely to increase heat loss during rewarming. This study aimed to evaluate the effect of wet clothing removal compared to containing the moisture using a vapor barrier on skin temperature in a prehospital setting.
Methods: This randomized crossover experimental field study was conducted in a snow cave in Hemsedal, Norway. After an initial cooling phase of 30 min while wearing wet clothes, the participants were subjected to one of two rewarming scenarios: (1) wet clothing removal and wrapping in a vapor barrier, insulating blankets, and windproof outer shell (dry group) or (2) wrapping in a vapor barrier, insulating blankets, and windproof outer shell (wet group). The mean skin temperature was the primary outcome whereas subjective scores for both thermal comfort and degree of shivering were secondary outcomes. Primary outcome data were analyzed using the analysis of covariance (ANCOVA).
Results: After an initial decrease in temperature during the exposure phase, the dry group had a higher mean skin temperature compared to the wet group after only 2 min. The skin-rewarming rate was highest in the initial rewarming stages for both groups, but increased in the dry group as compared to the wet group in the first 10 min. Return to baseline temperature occurred significantly faster in the dry group (mean 12.5 min [dry] vs. 28.1 min [wet]). No intergroup differences in the subjective thermal comfort or shivering were observed.
Conclusion: Removal of wet clothing in combination with a vapor barrier increases skin rewarming rate compared to encasing the wet clothing in a vapor barrier, in mild cold and environments without wind.publishedVersio
From generation to application: Exploring knowledge workers’ relations with GenAI
Get PDFGenerative AI (GenAI), has taken the world by storm and shown extremely promising effects across different fields, ranging from legal to medicine. Why these systems seemingly are better than existing knowledge management systems and expert AI systems while being more decentralized, is intriguing. To shed light on this novel phenomenon, we study knowledge workers in practice, attempting to understand relational generation and application of knowing with ChatGPT through 12 semistructured interviews with early adopters of the technology. We show how knowledge workers and GenAI i) generate relations and ii) apply relations. The findings outline activities like censoring input to GenAI, composing prompts, checking output, making mistakes, and asking for help as constituent practices of relational knowledge work. Furthermore, we outline how ChatGPT is relational in nature, and suggest implications for practice.acceptedVersio
Comparing assisting technologies for proficiency in cardiac morphology: 3D printing and mixed reality versus CT slice images for morphological understanding of congenital heart defects by medical students
Get PDFLearning cardiac morphology largely involves spatial abilities and studies indicate benefits from innovative 3D visualization technologies that speed up and increase the learning output. Studies comparing these teaching tools and their educational output are rare and few studies include complex congenital heart defects. This study compared the effects of 3D prints, mixed reality (MR) viewing of 3D meshes and standard cardiac CT slice images on medical students′ understanding of complex congenital heart defect morphology, measuring both objective level of understanding and subjective educational experience. The objective of this study was to compare morphological understanding and user experiences of 3D printed models, MR 3D visualization and axial 2D CT slices, in medical students examining morphological details in complex congenital heart defects. Medical students in the median 4th year of study (range 2nd to 6th) examined three of five different complex congenital heart defects by three different modalities: 3D printed model, MR viewed 3D mesh, and cardiac CT slices, answering a questionnaire on morphology and user experience. Time to complete task, diagnostic accuracy, and user experience data were collected and compared on group level. Task times were similar for all modalities. The percentage of correct answers was higher with MR visualization, which was also the preferred modality overall. Medical students both prefer and better understand the morphology of complex congenital heart disease with 3D models viewed using MR, without spending more time than with 3D prints or 2D CT images.publishedVersio