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Vortex-induced vibrations on wind turbine blades are a complex phenomenon not predictable by standard engineering models. For this reason, higher fidelity computational fluid dynamics (CFD) methods are needed. However, the term CFD covers a broad range of fidelities, and this study investigates which choices have to be made when wanting to capture the VIV phenomenon in a satisfying degree. The method studied is the so-called forced motion (FM) approach, where the structural motion is imposed on the CFD blade surface through modeshape assumptions rather than fully coupled two-way fluid structure interaction. In the study, two independent CFD solvers, EllipSys3D and Ansys CFX, are used and five different turbulence models of varying fidelities are tested. Varying flow scenarios are studied with respectively low to high inclination angles, which determine the component of the flow in the spanwise direction. In all scenarios, the cross-sectional component of the flow is close to perpendicular to the chord of the blade. It is found that the low and high inclination angle scenarios, despite having a difference equivalent to up to only thirty degrees azimuth, have quite different requirements of both grid resolution and turbulence models. For high inclination angles, where the flow has a large spanwise component from tip towards root, satisfying results are found from quite affordable grid sizes, and even with URANS k-ω turbulence the result is quite consistent with models resolving more of the turbulent scales. For low inclination, which has a high degree of natural vortex shedding, the picture is opposite. Here, even for scale resolving turbulence models, a much finer grid resolution is needed. This allows to capture the many incoherent vortices shed from the blade, which have a large impact on the coherent vortices, which inject power into the blade or extract power. It is found that a good consistency is seen using different variations of the higher fidelity hybrid RANS/LES turbulence models, like IDDES, SBES and k-ω SAS models, which agree well for various flow conditions and imposed amplitudes. This study shows that extensive care and consideration are needed when modelling 3D VIVs using CFD, as the flow phenomena, and thereby solver requirements, rapidly change for different scenarios.

This article examines some of the conditions that can explain the rise in young workers’ mental health and well-being problems in early work life. Based on 30 qualitative interviews with Danish workers under 30, who all had experienced different kinds of mental health and well-being problems in early work life, it shows how poor working environment and employment conditions often are triggering factors for young workers’ mental health and well-being problems. Mental health and well-being in early work life seem to be linked to the conditions through which young workers’ cultivate themselves as valuable working subjects in a time where work is a crucial arena for self-formation and self-realization. It is concluded that the combination of performance-oriented workplace cultures, temporary employment, and young workers’ aiming to achieve success in their work life, is a toxic combination for mental health and well-being. This article examines some of the conditions that can explain the rise in young workers’ mental health and well-being problems in early work life. Based on 30 qualitative interviews with Danish workers under 30, who all had experienced different kinds of mental health and well-being problems in early work life, it shows how poor working environment and employment conditions often are triggering factors for young workers’ mental health and well-being problems. Mental health and well-being in early work life seem to be linked to the conditions through which young workers’ cultivate themselves as valuable working subjects in a time where work is a crucial arena for self-formation and self-realization. It is concluded that the combination of performance-oriented workplace cultures, temporary employment, and young workers’ aiming to achieve success in their work life, is a toxic combination for mental health and well-being.

Fællesskaber forbindes stort set altid med noget godt. Det gælder også fællesskaber i ungdomslivet, der ofte betragtes som et svar på de udfordringer og den mistrivsel, som har spredt sig blandt nutidens unge. Fællesskaber anses som noget, der kan skabe stabilitet og tilhørsforhold i et ungdomsliv, som er præget af individualisering, præstationskultur, polarisering og andre forandringer og opbrud. Men fællesskaber er langtfra altid godt. De kan forstærke præstationspresset, øge polariseringen og skabe oplevelser af utilstrækkelighed og udenforskab.I denne bog præsenterer forfatterne en række nye forståelser og indsigter i unges fællesskaber, der kan nuancere billedet af, hvad fællesskaber er for en størrelse, hvilken betydning de har for nutidens unge, og hvornår de gør godt og ondt.Bogen stiller skarpt på, hvordan unges fællesskaber forandrer sig over tid, hvilke idealer de er omgærdet af, hvilke forskellige former de tager, samt hvilke positioner i fællesskaberne der er særligt svære at befinde sig i. Bogen bidrager også med opmærksomhedspunkter, der kan bruges i arbejdet med at skabe gode og opbyggende fællesskaber i ungdomslivet.Fællesskaber i ungdomslivet henvender sig både til praktikere, studerende, forskere, forældre og undervisere, der beskæftiger sig med fællesskaber og trivsel i ungdomslivet, samt til de aktører, der skaber rammerne for dette arbejde.Bogen er skrevet af forskere fra Center for Ungdomsforskning og bygger på resultaterne fra forskningsprojektet Kan ungefællesskaber gøre ondt?, som er blevet til i et samarbejde med Mary Fonden. Forskningsprojektet og bogen er muliggjort gennem en bevilling fra William Demant Fonden.

En personlig tolkning af ordet 'boomer' til den nye danske encyklopædi 'ORD'.

Reglerne om beregning af renter af skattekrav giver jævnligt anledning til praktiske problemer og har på det seneste ført til flere afgørelser fra domstolene. Kombinationen af meget høje rentesatser (sammenlignet med renteniveauet i øvrigt) og et vanskeligt tilgængeligt regelsæt burde påkalde sig en stor opmærksomhed i den skatteretlige litteratur. Dette er imidlertid ingenlunde tilfældet, ogselv Skatteministeriets pludselige bodsgang til Folketingets Skatteudvalg i 2020, hvor ministeriet oplyste, at Skattestyrelsen havdeopkrævet 4,5 mia. kr. i rente fra 46 skatteydere uden at have lovhjemmel, gav anledning til den mindste diskussion. I denne artikelomtales forskellige problemer, der knytter sig til renter af skattekrav.

Moving out from the childhood home is an essential transition in most young people’s lives. Based on the concept of ‘belonging’, this article explores how young people obtain a sense of belonging to a new place after leaving their childhood homes. The article explores the heterogeneous processes involved in the process of coming to belong to a new place. The article is based on a longitudinal interview study involving 36 Danish young people, whom we have followed for 12 months in their process of leaving home. In the interviews, the young people talk about their feelings and thoughts in relation to this transition. The initial period, in which young people establish themselves in a new place is often characterised by feelings of insecurity. The article shows how young people act upon these feelings and in doing so create a sense of belonging to a new place through heterogeneous affective, material, relational and spatial processes linked to self-construction. The article thereby nuances the concept of belonging and argues that the establishment of belonging to a new place is a multidimensional performative process of ‘holding oneself in place’. Moving out from the childhood home is an essential transition in most young people’s lives. Based on the concept of ‘belonging’, this article explores how young people obtain a sense of belonging to a new place after leaving their childhood homes. The article explores the heterogeneous processes involved in the process of coming to belong to a new place. The article is based on a longitudinal interview study involving 36 Danish young people, whom we have followed for 12 months in their process of leaving home. In the interviews, the young people talk about their feelings and thoughts in relation to this transition. The initial period, in which young people establish themselves in a new place is often characterised by feelings of insecurity. The article shows how young people act upon these feelings and in doing so create a sense of belonging to a new place through heterogeneous affective, material, relational and spatial processes linked to self-construction. The article thereby nuances the concept of belonging and argues that the establishment of belonging to a new place is a multidimensional performative process of ‘holding oneself in place’.

Højesteret har med SKM2022.241.H for første gang haft mulighed for at tage stilling til, hvad det betyder, at et selskab i det væsentlige er uden økonomisk risiko ved erhvervsmæssig aktivitet. Højesteret fastslog i dommen, at det skattemæssige underskud i et underskudsselskab, der var blevet solgt, ikke kunne anvendes til at nedbringe den skattepligtige indkomst.

A parked wind turbine can be subjected to large yaw angles, which causes vortex shedding. Under some particular inflow conditions, the interaction between the shed vorticity and the blade structure could lead to Vortex-Induced Vibrations (VIV). VIV are an instability where the response grows until it reaches a limit cycle oscillation. In this paper, we will focus on this last part of the response. We will see that the shedding makes the aeroelastic system linear time-periodic, and study its stability with Floquet theory. We will use high-fidelity simulations of different inflow conditions, and quantify the stability of the system using a model-free approach.

Østre Landsret har den 25. november 2021 afsagt dom i to sagerom kildeskat på renter betalt af danske datterselskaber tiludenlandske moderselskaber. De to sager var valgt ud somprøvesager og var blandt de i alt 6 sager om kildeskat på udbytteog renter, som lå til grund for EU-Domstolens principielle dommefra den 26. februar 2019.Østre Landsret gav i dommen Skatteministeriet fuldt medhold.Dommens resultat kom i lyset af Østre Landsrets dom i de toprøvesager om udbytte fra 3. maj 2021, SKM2021.304.ØLR, måskeikke som nogen stor overraskelse, og det må – som det var tilfældetmed SKM2021.304.ØLR – med stor sikkerhed forventes, atdommen bliver anket til Højesteret. Østre Landsrets begrundelseer imidlertid interessant og rækker videre end “blot” en stillingtagentil sagskomplekset i de to sager.

I 'Natur til et godt liv - Unges fortællinger om deres møder med naturen' præsenteres en undersøgelse af, hvilken betydning mødet med naturen kan have for unge, der deltager i naturintegrerede sociale indsatser. Undersøgelsen er udarbejdet af Center for Ungdomsforskning i et samarbejde med Natur til et godt liv-laboratoriet, som Bikubenfonden har igangsat med henblik på at kvalificere og vidensbasere det natursociale arbejde med unge på kanten af samfundet. Undersøgelsen viser et mangfoldigt natursocialt felt med store potentialer for mange forskellige grupper af unge. Den identificerer en række kvaliteter ved unges møder med naturen, men peger også på, at unge ikke altid oplever disse kvaliteter i naturmøderne. På den baggrund formuleres nogle væsentlige principper, der kan bidrage til den videre udvikling af natursociale indsatser for unge på kanten af samfundet. Rapporten henvender sig til praktikere, der arbejder med natursociale indsatser for unge, og til forskere, studerende, undervisere og beslutningstagere, der beskæftiger sig med ungdomsliv, udsathed og natur.