Sökresultat

Filtyp

Din sökning på "*" gav 549124 sökträffar

Thermal modeling of an ERS during static charging

Electric road systems (ERS) are designed to transfer power to electric vehicles (EV) while moving, not only for charging the on-board battery, but also for propelling the vehicle and supplying the auxiliary systems. The step from dynamic charging to static charging with a conductive ERS is not large since most of the equipment can be used without modification, yet it brings thermal challenges. Sta

Assessment of cooling integration with direct cooled windings

This paper presents and assesses the cooling integration of medium size electrical machines with distributed hair-pin type of windings. By introducing a hollow or profiled conductor the generated heat can be removed right where it is created. The cooling duct in conductor that can be connected either to series or parallel cooling flows increases DC resistance up to 1.5 times when comparing commerc

Alternative EV powertrain topologies designed for operation in a conductive electric road system

Electric road systems (ERS) are technologies that allow to charge electric vehicles (EVs) while they are driving. This makes it possible to reduce the installed battery capacity and therefore the weight and cost of the vehicle. However, while the vehicle is charging from the ERS a protective earth connection cannot be ensured, which introduces new isolation challenges in the design of the electric

New satellite-based estimates show significant trends in spring phenology and complex sensitivities to temperature and precipitation at northern European latitudes

Recent climate warming has altered plant phenology at northern European latitudes, but conclusions regarding the spatial patterns of phenological change and relationships with climate are still challenging as quantitative estimates are strongly diverging. To generate consistent estimates of broad-scale spatially continuous spring plant phenology at northern European latitudes (> 50° N) from 2000

Increased mortality in non-alcoholic fatty liver disease with chronic kidney disease is explained by metabolic comorbidities

Background: There is a close association between non-alcoholic fatty liver disease (NAFLD) and prevalent chronic kidney disease (CKD). Few longitudinal studies exist. No previous study has investigated to what extent CKD affects mortality in biopsy-proven NAFLD. Our aim was to investigate the long-term risk of developing CKD in biopsy-proven NAFLD and its effect on mortality. Methods: Patients wi

Wild-caught great tits Parus major fail to use tools in a laboratory experiment, despite facilitation

Studies investigating tool use in animals that are not known tool users in the wild are important in helping to understand how and under what circumstances this ability might arise. Tool use appears to be uncommon in great tits (Parus major), with only a single documented observation in which a wild great tit used conifer needles to extract larvae from crevices in trees. In a laboratory-based expe

What future for primates? Conservation struggles in the forests of Cross River State, Nigeria

While deforestation and forest degradation have gained attention in recent years not least at the UN climate negotiations, a third “de”, i.e., defaunation, has to a great extent been overlooked. Human-induced faunal loss does not only reduce tree species diversity, but also significantly erodes key ecosystem services and functions and further disadvantages local communities. In this article, we an

The Preparation of Decellularized Mouse Lung Matrix Scaffolds for Analysis of Lung Regenerative Cell Potential

Lung transplantation is the only option for patients with end-stage lung disease, but there is a shortage of available lung donors. Furthermore, efficiency of lung transplantation has been limited due to primary graft dysfunction. Recent mouse models mimicking lung disease in humans have allowed for deepening our understanding of disease pathomechanisms. Moreover, new techniques such as decellular

Computed electronic and optical properties of SnO2 under compressive stress

We consider the effects of three different types of applied compressive stress on the structural, electronic and optical properties of rutile SnO2. We use standard density functional theory (DFT) to determine the structural parameters. The effective masses and the electronic band gap, as well as their stress derivatives, are computed within both DFT and many-body perturbation theory (MBPT). The st

10Be and Cosmogenic Radionuclides in Ice Cores

This article summarizes the processes that are responsible for cosmogenic radionuclide variations in ice cores and the results that can be inferred from these records. The article starts with the production in the atmosphere caused by the influx of galactic cosmic ray particles and its modulation by the solar and geomagnetic fields. Subsequently, the geochemical behavior of cosmogenic radionuclide

Quasiparticle electronic structure of barium-silicon oxynitrides for white-LED application

Ba3Si6O12N2:Eu2+ and Ba3Si6O9N4:Eu2+ have strikingly similar atomistic structures, but the former is an efficient green phosphor at working temperature while the latter is a bluish-green phosphor whose luminescence decreases quite fast with temperature. Aiming at the understanding of such different behavior, we compute the quasiparticle electronic band structure of the two hosts, Ba3Si6O 12N2 and

Band widths and gaps from the Tran-Blaha functional : Comparison with many-body perturbation theory

For a set of ten crystalline materials (oxides and semiconductors), we compute the electronic band structures using the Tran-Blaha (TB09) functional. The band widths and gaps are compared with those from the local-density approximation (LDA) functional, many-body perturbation theory (MBPT), and experiments. At the density-functional theory (DFT) level, TB09 leads to band gaps in much better agreem

Climate-fire interactions and Savanna ecosystems : A dynamic vegetation modeling study for the African Continent

Savannas are inherently “disturbed” ecosystems, but the regularly recurring disruptions play such a fundamental ecological role (Scholes and Archer, 1997) that “episodic events” rather than “disturbance” may the more apt terminology. From an atmospheric perspective, fire is the most significant of these episodic events. Fires shape community species composition; tree to grass ratio and nutrient re

Electronic properties of interfaces and defects from many-body perturbation theory : Recent developments and applications

We review some recent developments in many-body perturbation theory (MBPT) calculations that have enabled the study of interfaces and defects. Starting from the theoretical basis of MBPT, Hedin's equations are presented, leading to the GW and GWΓ approximations. We introduce the perturbative approach, that is the one most commonly used for obtaining quasiparticle (QP) energies. The practical strat

G0W0 band gap of ZnO : Effects of plasmon-pole models

Carefully converged calculations are performed for the band gap of ZnO within many-body perturbation theory (G0W0 approximation). The results obtained using four different well-established plasmon-pole models are compared with those of explicit calculations without such models (the contour-deformation approach). This comparison shows that, surprisingly, plasmon-pole models depending on the f-sum r

GW approximations and vertex corrections on the Keldysh time-loop contour : Application for model systems at equilibrium

We study the effects of self-consistency and vertex corrections on different GW-based approximations for model systems of interacting electrons. For dealing with the most general case, we use the Keldysh time-loop contour formalism to evaluate the single-particle Green's functions. We provide the formal extension of Hedin's GW equations for the Green's function in the Keldysh formalism. We show an

Hembesök som brandförebyggande arbete

Följande rapport är genomförd inom forskningsprojektet Bostadsbränder i storstadsområden - rumsliga skillnader och brandsäkerhetsarbete i den socialt fragmenterade staden. Projektet är finansierat av MSB och har Institutionen för Urbana studier på Malmö universitet och Institutionen för kulturgeografi och ekonomisk geografi vid Lunds universitet som bas. Denna rapport fokuserar på hembesök som för