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Modalselva - en kunnskapsoppsummering 2024
Full text linkDet pågår et betydelig prosjekt for å gjenopprette laksebestanden i Modalselva, og behovet for en kunnskapsoppsummering er stort. Foreliggende rapport inkluderer data om effektene av vassdragsregulering, forsuring og kalking, samt tiltak som rognplanting og slep av klekkerismolt. Videre beskriver den planene for innfangning og slep av villsmolt fra 2024. Formålet er å gi et helhetlig bilde av status og å prioritere fremtidige tiltak for å støtte laksestammens gjenoppretting.Modalselva - en kunnskapsoppsummering 2024publishedVersio
Operational Strategies of Two-Spool Micro Gas Turbine With Alternative Fuels: A Performance Assessment
Full text link© 2024 by ASMEMicro gas turbines (mGT) have not yet succeeded in conquering the small-scale combined heat and power (CHP) market. One reason is that their electrical efficiency is not high enough to maintain a cost-effective operation. A two-shaft intercooled mGT has the potential to meet the current market demand. This technology maintains a high electrical efficiency even at part-load and coupled with its fuel-flexible combustion chamber, it is an ideal candidate for CHP concepts in a renewable future. In this paper, performance analysis on two-spool mGT is carried out with various fuel blends. Attention is given to the low-pressure and high-pressure compressors and the variation of surge margin by adding hydrogen and syngas. Two control strategies for the mGT are adopted. In the first scenario, the two shafts have equal rotational speeds while in the second, the speeds are controlled independently. As the engine is operated at equal speeds, the maximum performance with 100 vol. % of syngas is observed at 85% of the nominal load while 100 vol. % of hydrogen shows maximum efficiency at a load of 63.7%. At electric power lower than 60% and for high amounts of syngas in natural gas, the low-pressure compressor (LPC) operates closely to surge line. In the second scenario, the efficiency increases as the load decreases and the LPC runs in an efficient and safe operating region. Additionally, the amount of nitrogen in syngas affects the part-load performance of the two-spool mGT.publishedVersio
Decomposition of physical processes controlling EASM precipitation changes during the mid-Piacenzian: new insights into data–model integration
Full text linkThe mid-Piacenzian warm period (MPWP, ~3.264–3.025 Ma) has gained widespread interest due to its partial analogy with future climate. However, quantitative data–model comparison of East Asian Summer Monsoon (EASM) precipitation during the MPWP is relatively rare, especially due to problems in decoding the imprint of physical processes to climate signals in the records. In this study, pollen-based precipitation records are reconstructed and compared to the multi-model ensemble mean of the Pliocene Model Intercomparison Project Phase 2 (PlioMIP2). We find spatially consistent precipitation increase in most simulations but a spatially divergent change in MPWP records. We reconcile proxy data and simulation by decomposing physical processes that control precipitation. Our results 1) reveal thermodynamic control of an overall enhancement of EASM precipitation and 2) highlight a distinct control of thermodynamic and dynamical processes on increases of tropical and subtropical EASM precipitation, reflecting the two pathways of water vapor supply that enhance EASM precipitation, respectively.publishedVersio
Overview of how the Calculation of Dynamic Temperature of Drilling Fluids is Closely Linked with Rheology
No full textBased on many years of work with the calculation of dynamic temperature of drilling fluids during operations, a pedagogic overview of how the calculation of heat transfer and temperature is closely linked with fluid flow properties will be given. For example, the onset of vortices and turbulence due to imposed flow and rotation of the drill string / running string has a large impact on heat transfer. Changing from idealized laminar flow with only conduction radially to flow with vortices and turbulence with convective heat transfer also radially, causes a large boost of heat transfer, especially along the outer wall of the drill string. Clearly, the rheological behaviour of the fluid is essential. Different vibrational modes and other disturbances add to the complexity of the picture, such that some effects can be modelled from first principles, while others are too complicated for practical models and must be handled differently.publishedVersio
Heterogeneous Multi-Robot Collaboration for Coverage Path Planning in Partially Known Dynamic Environments
Full text linkThis research presents a cooperation strategy for a heterogeneous group of robots that comprises two Unmanned Aerial Vehicles (UAVs) and one Unmanned Ground Vehicles (UGVs) to perform tasks in dynamic scenarios. This paper defines specific roles for the UAVs and UGV within the framework to address challenges like partially known terrains and dynamic obstacles. The UAVs are focused on aerial inspections and mapping, while UGV conducts ground-level inspections. In addition, the UAVs can return and land at the UGV base, in case of a low battery level, to perform hot swapping so as not to interrupt the inspection process. This research mainly emphasizes developing a robust Coverage Path Planning (CPP) algorithm that dynamically adapts paths to avoid collisions and ensure efficient coverage. The Wavefront algorithm was selected for the two-dimensional offline CPP. All robots must follow a predefined path generated by the offline CPP. The study also integrates advanced technologies like Neural Networks (NN) and Deep Reinforcement Learning (DRL) for adaptive path planning for both robots to enable real-time responses to dynamic obstacles. Extensive simulations using a Robot Operating System (ROS) and Gazebo platforms were conducted to validate the approach considering specific real-world situations, that is, an electrical substation, in order to demonstrate its functionality in addressing challenges in dynamic environments and advancing the field of autonomous robots.publishedVersio
Legevaktorganisering i Norge: Rapport fra Nasjonalt legevaktregister 2024
Full text linkNKLM sendte spørreundersøkelsen til alle landets legevakter tidlig i januar 2024. Formålet var å oppdatere Nasjonalt legevaktregister og hovedtema var bemanning, rekruttering og nasjonale kvalitetsindikatorer for legevakt. Rapporten inneholder primært oppsummeringer og tall på nasjonalt - og fylkesnivå. Resultater fra enkeltlegevakter blir ikke presentert i rapporten. Kvalitetsindikatorer for enkeltlegevakter er tilgjengelig på Helsedirektoratet sine nettsider Akuttmedisinske tjenester utenfor sykehus - Helsedirektoratet .Legevaktorganisering i Norge: Rapport fra Nasjonalt legevaktregister 2024publishedVersio
Music in Care Home Settings: Guidelines for Implementation and Evaluation Based on the Music Interventions for Depression and Dementia in ELderly Care (MIDDEL) Study in the UK
Full text linkContext: Music-based interventions are widely acknowledged to promote the wellbeing of care home residents, particularly those whose communication is impaired, such as through stroke or dementia. Yet in such settings the use of music is limited for reasons that are not entirely clear. Objectives: The Music Interventions for Depression and Dementia in ELderly care (MIDDEL) trial in 16 English care homes was used as a case study to highlight key issues which appear to affect the successful implementation and evaluation of music-based interventions. Methods: The fidelity data from the MIDDEL trial was used to develop inferences in consultation with interventionists and researchers. Based on the literature about implementing psychosocial interventions in care homes and data from this study, a checklist was developed to enhance implementation and research pertaining to music-based interventions in care homes. Findings: New insights were found on the adherence of interventionists to the fidelity criteria. Pragmatic issues relevant to conducting a trial immediately after a pandemic are highlighted, including: the difficulties of maintaining engagement with care home personnel and the practicalities of delivering an intensive intervention to a population who have depression and dementia. We derive recommendations for improving future interventional studies in care homes. Limitations: The participating care homes may not be representative of the industry. The Covid pandemic complicated the study in numerous ways documented here. Implications: The lessons learned offer guidance for future implementation and research on music-based interventions in residential care settings.publishedVersio
Parental unemployment and educational outcomes in late adolescence: the importance of family cohesion, parental education, and family income in a Norwegian study
Full text linkAims: The study aimed to investigate the association between parental unemployment and grade point average and school completion in adolescence, and the importance of family cohesion, parental education, and family income in explaining these associations. Methods: Data stem from the Norwegian cross-sectional 2012 youth@hordaland-survey including 8437 adolescents (53.4% girls). Information on grade point average, school completion, parental education, and family income were retrieved from the National Education Database. Parental work status and family cohesion were assessed by adolescent self-report. Results: Adolescents with at least one unemployed parent had lower grade point averages (3.49 compared with 3.92, P<0.001) and rates of school completion (71.9% compared with 86.6%, P<0.001) compared with adolescents with two working parents. The associations between parental unemployment and both grade point average (b = −0.22, 95% confidence interval −0.32, –0.12) and school completion (odds ratio 0.59, 95% confidence interval 0.46, 0.76) partly attenuated but remained significant when taking family cohesion, parental education, and family income into account. There was a significant interaction between parental unemployment and family cohesion on grade point average, in which the positive association between family cohesion and grade point average was weaker for adolescents with unemployed parents. Conclusions: Adolescents with parents outside of the workforce are at higher risk of poorer educational outcomes than peers with working parents. Combined with the positive associations between parental education, family cohesion, family income, and educational outcomes, this underscores the importance of parents for adolescent educational outcomes, and suggests that parents and the family situation should be considered when providing academic support for adolescents who struggle in upper secondary school.publishedVersio
Leveraging tensor kernels to reduce objective function mismatch in deep clustering
Full text linkObjective Function Mismatch (OFM) occurs when the optimization of one objective has a negative impact on the optimization of another objective. In this work we study OFM in deep clustering, and find that the popular autoencoder-based approach to deep clustering can lead to both reduced clustering performance, and a significant amount of OFM between the reconstruction and clustering objectives. To reduce the mismatch, while maintaining the structure-preserving property of an auxiliary objective, we propose a set of new auxiliary objectives for deep clustering, referred to as the Unsupervised Companion Objectives (UCOs). The UCOs rely on a kernel function to formulate a clustering objective on intermediate representations in the network. Generally, intermediate representations can include other dimensions, for instance spatial or temporal, in addition to the feature dimension. We therefore argue that the naïve approach of vectorizing and applying a vector kernel is suboptimal for such representations, as it ignores the information contained in the other dimensions. To address this drawback, we equip the UCOs with structure-exploiting tensor kernels, designed for tensors of arbitrary rank. The UCOs can thus be adapted to a broad class of network architectures. We also propose a novel, regression-based measure of OFM, allowing us to accurately quantify the amount of OFM observed during training. Our experiments show that the OFM between the UCOs and the main clustering objective is lower, compared to a similar autoencoder-based model. Further, we illustrate that the UCOs improve the clustering performance of the model, in contrast to the autoencoder-based approach. The code for our experiments is available at https://github.com/danieltrosten/tk-uco.publishedVersio
Underestimated Land Heat Uptake Alters the Global Energy Distribution in CMIP6 Climate Models
Full text linkCurrent global warming results in an uptake of heat by the Earth system, which is distributed among the different components of the climate system. However, current-generation climate models deliver heat inventory and partitioning estimates of Earth system components that differ from recent observations. Here we investigate the global heat distribution under warming by using fully-coupled CMIP6 Earth system model experiments, including a version of the MPI-ESM with a deep land model component, accommodating the required space for more realistic terrestrial heat storage. The results show that sufficiently deep land models exert increased subsurface land heat uptake, leading to a heat uptake partitioning among the Earth system components that is closer to observational estimates. The results are relevant for the understanding of Earth's heat partitioning and highlight the importance of the land heat sink in the Earth heat inventory.publishedVersio