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Your search keyword '"Erbs-Hansen, Dorthe Reng"' showing total 17 results
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17 results on '"Erbs-Hansen, Dorthe Reng"'

1. Inverse modelling and classification of magnetic responses to improve marine unexploded ordnance rationalization.

Author

Brighouse, Jack, Wood, Martin, McGregor, Eoin, Kirkland, Andrew, Sinclair, David, Erbs-Hansen, Dorthe Reng, and Hviid, Simon

Subjects
WIND power, OPTIMIZATION algorithms, ORDNANCE, OFFSHORE wind power plants, WIND power plants, CLASSIFICATION, MAGNETIC anomalies
Abstract

Unexploded ordnance (UXO), often deployed in WWI and WWII, are still present on the seabed posing a risk to seabed construction. UXO surveys identify potential UXO targets which are then investigated and removed where necessary; however, approximately 96 per cent of targets investigated on projects included in this study were non-UXO (false positives). Here we investigate methods of improving statistical confidence in targets picked through the improved classification of magnetic response, utilizing simulation methods and historic data. A simulation of the induced magnetism of UXO was developed to model the most likely dimensions and orientation of a given source item. Modelling results and measured variables were combined in an optimization algorithm, hereon referred to as 'the classifier'. We document the results of integrating the magnetic responses of 3027 targets from 18 offshore wind projects into the classifier. Five of these projects were performed as tests in which the target results were unknown during classification. Finally, the classifier was deployed on a live project, Hollandse Kust Zuid 3 and 4 Offshore Wind Farm, in which it enabled the removal of 67 targets from the from the 1200-target investigation list. The classifier proved to be a valuable additional tool to assist the target rationalization process, reliably and repeatably distinguishing UXO from other items, thereby reducing false positives and repeatably demonstrating no threshold UXO false negatives. Assumptions and limitations of this methodology were highlighted, which must be understood and considered when integrating this approach on future projects. [ABSTRACT FROM AUTHOR]

Published
2024
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4. Late Younger Dryas and early Holocene palaeoenvironments in the Skagerrak, eastern North Atlantic: a multiproxy study

Author

ERBS-HANSEN, DORTHE RENG, Knudsen, Karen Luise, GARY, ANTHONY CAVEDO, Jansen, Eystein, Gyllencreutz, Richard, Scao, Vincent, Lambeck, Kurt, Aarhus University [Aarhus], University of Utah, Bjerknes Centre for Climate Research (BCCR), Department of Biological Sciences [Bergen] (BIO / UiB), University of Bergen (UiB)-University of Bergen (UiB), Stockholm University, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Paléocéanographie (PALEOCEAN), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Climate Change Institute at the Australian National University, Australian National University (ANU), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), and Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)

Subjects
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2011

15. Holocene climatic development in Skagerrak, eastern North Atlantic : Foraminiferal and stable isotopic evidence

Author

Erbs-Hansen, Dorthe Reng, Knudsen, Karen Luise, Gary, Anthony Cavedo, Gyllencreutz, Richard, Jansen, Eystein, Erbs-Hansen, Dorthe Reng, Knudsen, Karen Luise, Gary, Anthony Cavedo, Gyllencreutz, Richard, and Jansen, Eystein

Abstract

A high-resolution multiproxy study of core MD99-2286 reveals a highly variable hydrographic environment in the Skagerrak from 9300 cal. yr BP to the present. The study includes foraminiferal faunas, stable isotopes and sedimentary parameters, as well as temperature and salinity reconstructions of a c. 29 m long radiocarbon-dated core record. The multivariate technique fuzzy c-means was applied to the foraminiferal counts, and it was extremely valuable in defining subtle heterogeneities in the foraminiferal faunal data corresponding to hydrographic changes. The major early-/mid-Holocene (Littorina) transgression led to flooding of large former land areas in the North Sea, the opening of the English Channel and Danish straits, and initiation of the modern circulation system. This is reflected by fluctuating C/N values and an explosive bloom of Hyalinea balthica. A slight indication of ameliorated conditions between 8000 and 5750 cal. yr BP is related to the Holocene Thermal Maximum. A subsequent increase in freshwater/Baltic water influence between 5750 and 4350 cal. yr BP is reflected by dominance of Bulimina marginata and depleted delta O-18 values. The Neoglacial cooling (after 4350 cal. yr BP) is seen in the Skagerrak as enhanced turbidity, increasing TOC values and short-term changes in an overall Cassidulina laevigata-dominated fauna suggesting a prevailing influence of Atlantic waters. This is in agreement with increased strength of westerly winds, as recorded for this period. The last 2000 years were also dominated by Atlantic Water conditions with generally abundant nutrient supply. However, during warm periods, particularly the 'Medieval Warm Period'and the modern warming, the area was subject to a restriction in the supply of nutrients and/or the nutrient supply had a more refractory character., 5

Published
2012
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