1,300 research outputs found
Modelling Transport in an Interregional General Equilibrium Model with Externalities
In this working paper the regional impacts of road pricing on cars are analysed taking into account externality effects from transportation on wages and productivity. In the paper the direct impacts from changes in transport costs on level of wages and productivity (=direct externality effects) have been estimated. The direct and derived impacts of road pricing have been analysed with AKF’s local economic model LINE and include the impacts on regional production, income and employment. LINE is an interregional general equilibrium model, which uses an interregional social accounting matrix (SAM-K) and a regional transport satellite account as the basis for modelling. Additionally, data from a GIS-system (Technical University of Copenhagen) on transport costs have been included to estimate the demand for transport commodities and increase in transport demand and costs due to road pricing. The direct effects on level of wages and productivity have been included into the model together with all the direct effects on commodity prices from road pricing. In the working paper the total impacts of road pricing have been subdivided into 2 components: 1) The wage effects of reducing income net of commuting of increasing transport cost by introduction of road pricing, 2) the labour contraction effect from increasing wages through increase in commuting cost and 3) the negative productivity effects of introducing road pricing. In total the impacts of road pricing are substantial. Regions with high level of average commuting cost (suburban areas in Greater Copenhagen) suffers most, whereas the centre of Copenhagen suffers least because of short commuting distances. In rural areas impacts are on or just below average because low level of road pricing.
Tuning Yu-Shiba-Rusinov States in a Quantum Dot
We present transport spectroscopy of sub-gap states in a bottom gated InAs
nanowire coupled to a normal lead and a superconducting aluminium lead. The
device shows clearly resolved sub-gap states which we can track as the coupling
parameters of the system are tuned and as the gap is closed by means of a
magnetic field. We systematically extract system parameters by using numerical
renormalization group theory fits as a level of the quantum dot is tuned
through a quantum phase transition electrostatically and magnetically. We also
give an intuitive description of sub-gap excitations.Comment: 9 pages, 10 figure
Gaps below strange star crusts
The gap caused by a strong electric field between the quark surface and
nuclear crust of a strange star is studied in an improved model including
gravity and pressure as well as electrostatic forces. The transition from gap
to crust is followed in detail. The properties of the gap are investigated for
a wide range of parameters assuming both color-flavor locked and non
color-flavor locked strange star cores. The maximally allowed crust density is
generally lower than that of neutron drip. Finite temperature is shown to
increase the gap width, but the effect is significant only at extreme
temperatures. Analytical approximations are derived and shown to provide useful
fits to the numerical results.Comment: 12 pages incl. 14 figures. To appear in Physical Review
The role of aquaporins in the kidney of euryhaline teleosts
Water balance in teleost fish is maintained with contributions from the major osmoregulatory organs: intestine, gills and kidney. Overall water fluxes have been studied in all of these organs but not until recently has it become possible to approach the mechanisms of water transport at the molecular level. This mini-review addresses the role of the kidney in osmoregulation with special emphasis on euryhaline teleosts. After a short review of current knowledge of renal functional morphology and regulation, we turn the focus to recent molecular investigations of the role of aquaporins in water and solute transport in the teleost kidney. We conclude that there is much to be achieved in understanding water transport and its regulation in the teleost kidney and that effort should be put into systematic mapping of aquaporins to their tubular as well as cellular localization
Direct observation of interface and nanoscale compositional modulation in ternary III-As heterostructure nanowires
Straight, axial InAs nanowire with multiple segments of GaInAs were grown.
High resolution X-ray energy-dispersive spectroscopy (EDS) mapping reveal the
distribution of group III atoms at the axial interfaces and at the sidewalls.
Significant Ga enrichment, accompanied by a structural change is observed at
the GaInAs/InAs interfaces and a higher Ga concentration for the early grown
GaInAs segments. The elemental map and EDS line profile infer Ga enrichment at
the facet junctions between the sidewalls. The relative chemical potentials of
ternary alloys and the thermodynamic driving force for liquid to solid
transition explains the growth mechanisms behind the enrichment.Comment: 12 Pages, 4 figure
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