We study which quadratic forms are representable as the local degree of a map f:An→An with an isolated zero at 0 , following the work of Kass and Wickelgren who established the connection to the quadratic form of Eisenbud, Khimshiashvili, and Levine. Our main observation is that over some base fields k , not all quadratic forms are representable as a local degree. Empirically the local degree ...

Polar mesospheric summer echo (PMSE) formation is linked to charged dust/ice particles in the mesosphere. We investigate the modulation of PMSEs with radio waves based on measurements with EISCAT VHF radar and EISCAT heating facility during low solar illumination. The measurements were made in August 2018 and 2020 around 20:02 UT. Heating was operated in cycles with intervals of 48 s on and 168 ...

Statistiske metoder som regresjonsanalyse og kausale design basert på naturlige eksperi-menter har etter hvert blitt hyllevare innen de fleste fag som behandler store datamengder,ikke minst innen epidemiologi, meteorologi og klimavitenskap.1 Et eksempel er prinsipalkomponentanalyse (PCA), som brukes til å finne karakteristiske mønstre i geofysiske felt.Mønstrene, eller prinsipalkomponentene, ...

Standard strategies for fully supervised semantic segmentation of medical images require large pixel-level annotated datasets. This makes such methods challenging due to the manual labor required and limits the usability when segmentation is needed for new classes for which data is scarce. Few-shot segmentation (FSS) is a recent and promising direction within the deep learning literature designed ...

In a fusion reactor, coherent structures of hot and dense plasma can drift radially outwards due to the conditions of the edge plasma and can cause erosion of the outer walls. This erosion can release impurities into the plasma and harm equipment at the walls. This thesis presents two methods of tracking blobs in the boundary region of fusion experiments. The first model is a simple Long Short-Term ...

The mechanism of the asymmetric hydrogenation of prochiral enamides by well-defined, neutral bis(phosphine) cobalt(0) and cobalt(II) precatalysts has been explored using(R,R)-^iPrDuPhos ((R,R)-^iPrDuPhos = (+)-1,2-bis[(2R,5R)-2,5-diisopropylphospholano]benzene) as a representative chiral bis(phosphine) ligand. A series of (R,R)-(^iPrDuPhos)Co(enamide) (enamide = ...

In a risk analysis we identify the causes that could lead to unwanted events/ outcomes. We introduce barriers that will reduce the probabilities of such events and also barriers that will mitigate the consequences of such events.<p> <p>Regarding Arctic Marine Transportation Challenges, more attention should be placed on communicating all work that is undertaken to enhance the safety and limit ...

The Historical Population Register (HPR) is a project to build the longitudinal life history of individuals by integrating the historical records of the people in Norway since the 19th century. This study attempted to improve the linking rate between the 1875-1900 censuses in HPR, which is currently low, using machine learning approaches. To this end, I developed a machine learning model for linking ...

PalaeoArc (Processes and Palaeo-Environmental Changes in the Arctic: From Past to Present) is an international network research programme, the aim of which is to understand and explain the climatically induced environmental changes in the Arctic that have taken place throughout the Quaternary and continue in the present-day (see http://www.palaeoarc.no/). This network builds on and extends the ...

Ocean plastic pollution is a problem of increasing magnitude; yet, the amount of plastic at the sea surface is much lower than expected. Solar ultraviolet (UV) radiation can induce photodegradation, but its importance in determining the longevity of floating plastic remains unconstrained. Here, we measured photodegradation rates of different plastic types slightly larger than microplastics (virgin ...