15,525 research outputs found
Intelligent management of on-street parking provision for the autonomous vehicles era
The increasing degree of connectivity between vehicles and infrastructure, and the impending deployment of autonomous vehicles (AV) in urban streets, presents unique opportunities and challenges regarding the on-street parking provision for AVs. This study develops a novel simulation-optimisation approach for intelligent curbside management, based on a metaheuristic technique. The hybrid method balances curb lanes for driving or parking, aiming to minimise the average traffic delay. The model is tested using an idealised grid layout with a range of flow rates and parking policies. Results demonstrate delay decreased by 9%-27% from the benchmark case. Additionally, the traffic delay distribution shows the trade-offs between expanding road capacity and minimising traffic demand through curb management, indicating the interplay between curb parking and traffic management in the AV era
Relaxation of Spin Polarized He in Mixtures of He and He Below the He Lambda Point
We report the first study of the depolarization behavior of spin polarized
3He in a mixture of 3He-4He at a temperature below the 4He Lambda point in a
deuterated TetraPhenyl Butadiene-doped deuterated PolyStyrene (dTPB-dPS) coated
acrylic cell. In our experiment the measured 3He relaxation time is due to the
convolution of the 3He longitudinal relaxation time, T1, and the diffusion time
constant of 3He in superfluid 4He since depolarization takes place on the
walls. We have obtained a 3He relaxation time ~3000 seconds at a temperature
around 1.9K. We have shown that it's possible to achieve values of wall
depolarization probability on the order of (1-2)x10^-7 for polarized 3He in the
superfluid 4He from a dTPB-dPS coated acrylic surface.Comment: The Model used to interpret the data has been change
Planar cyclotron motion in unidirectional superlattices defined by strong magnetic and electric fields: Traces of classical orbits in the energy spectrum
We compare the quantum and the classical description of the two-dimensional
motion of electrons subjected to a perpendicular magnetic field and a
one-dimensional lateral superlattice defined by spatially periodic magnetic and
electric fields of large amplitudes. We explain in detail the complicated
energy spectra, consisting of superimposed branches of strong and of weak
dispersion, by the correspondence between the respective eigenstates and the
``channeled'' and ``drifting'' orbits of the classical description.Comment: 11 pages, 11 figures, to appear in Physical Review
New pulse profile variability associated with a glitch of PSR J0738-4042
The close correlation observed between emission state and spin-down rate
change of pulsars has many implications both for the magnetospheric physics and
the neutron star interior. The middle-aged pulsar PSR J07384042, which had
been observed to display variations in the pulse profile associated with its
spin-down rate change due to external effects, is a remarkable example. In this
study, based on the 12.5-yr combined public timing data from UTMOST and Parkes,
we have detected a new emission-rotation correlation in PSR J07384042
concurrent with a glitch. A glitch that occurred at MJD 57359(5) (December 3,
2015) with is the first glitch event
observed in this pulsar and is probably the underlying cause of the
emission-rotation correlation. Unlike the usual post-glitch behaviours, the
braking torque on the pulsar has continued to increase over 1380 d,
corresponding to a significant decrease in . As for changes in the
pulse profile after the glitch, the relative amplitude of the leading component
weakens drastically, while the middle component becomes stronger. A combined
model of crustquake induced platelet movement and vortex creep response is
invoked to account for this rare correlation. In this scenario, magnetospheric
state-change is naturally linked to the pulsar-intrinsic processes that give
rise to a glitch.Comment: 13 pages, 6 figures. Accepted for publication in MNRAS. Comments
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Chronic activation of PPARα with fenofibrate reduces autophagic proteins in the liver of mice independent of FGF21
Autophagy is a catabolic mechanism to degrade cellular components to maintain cellular energy levels during starvation, a condition where PPARα may be activated. Here we report a reduced autophagic capacity in the liver following chronic activation of PPARα with fenofibrate (FB) in mice. Chronic administration of the PPARα agonist FB substantially reduced the levels of multiple autophagy proteins in the liver (Atg3, Agt4B, Atg5, Atg7 and beclin 1) which were associated with a decrease in the light chain LC3II/LC3I ratio and the accumulation of p62. This was concomitant with an increase in the expression of lipogenic proteins mSREBP1c, ACC, FAS and SCD1. These effects of FB were completely abolished in PPARα-/- mice but remained intact in mice with global deletion of FGF21, a key downstream mediator for PPARα-induced effects. Further studies showed that decreased the content of autophagy proteins by FB was associated with a significant reduction in the level of FoxO1, a transcriptional regulator of autophagic proteins, which occurred independently of both mTOR and Akt. These findings suggest that chronic stimulation of PPARα may suppress the autophagy capacity in the liver as a result of reduced content of a number of autophagy-associated proteins independent of FGF21
Design and analysis of fractional factorial experiments from the viewpoint of computational algebraic statistics
We give an expository review of applications of computational algebraic
statistics to design and analysis of fractional factorial experiments based on
our recent works. For the purpose of design, the techniques of Gr\"obner bases
and indicator functions allow us to treat fractional factorial designs without
distinction between regular designs and non-regular designs. For the purpose of
analysis of data from fractional factorial designs, the techniques of Markov
bases allow us to handle discrete observations. Thus the approach of
computational algebraic statistics greatly enlarges the scope of fractional
factorial designs.Comment: 16 page
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