2,112 research outputs found
Energy Efficiency and Emission Testing for Connected and Automated Vehicles Using Real-World Driving Data
By using the onboard sensing and external connectivity technology, connected
and automated vehicles (CAV) could lead to improved energy efficiency, better
routing, and lower traffic congestion. With the rapid development of the
technology and adaptation of CAV, it is more critical to develop the universal
evaluation method and the testing standard which could evaluate the impacts on
energy consumption and environmental pollution of CAV fairly, especially under
the various traffic conditions. In this paper, we proposed a new method and
framework to evaluate the energy efficiency and emission of the vehicle based
on the unsupervised learning methods. Both the real-world driving data of the
evaluated vehicle and the large naturalistic driving dataset are used to
perform the driving primitive analysis and coupling. Then the linear weighted
estimation method could be used to calculate the testing result of the
evaluated vehicle. The results show that this method can successfully identify
the typical driving primitives. The couples of the driving primitives from the
evaluated vehicle and the typical driving primitives from the large real-world
driving dataset coincide with each other very well. This new method could
enhance the standard development of the energy efficiency and emission testing
of CAV and other off-cycle credits
Effects of periodically modulated coupling on amplitude death in nonidentical oscillators
The effects of periodically modulated coupling on amplitude death in two
coupled nonidentical oscillators are explored. The AD domain could be
significantly influenced by tuning the modulation amplitude and the modulation
frequency of the modulated coupling strength. There is an optimal value of
modulation amplitude for the modulated coupling with which the largest AD
domain is observed in the parameter space. The AD domain is enlarged with the
decrease of the modulation frequency for a given small modulation amplitude,
while is shrunk with decrease of the modulation frequency for a given large
modulation amplitude. The mechanism of AD in the presence of periodic
modulation in the coupling is investigated via the local condition Lyapunov
exponent of the coupled system. The stability of AD state can be well
characterized by conditional Lyapunov exponent. The coupled system experiencing
from the oscillatory state to AD is clearly indicated by the observation that
the conditional Lyapunov exponent transits from positive to negative. Our
results are helpful to many potential applications for the research of
neuroscience and dynamical control in engineering.Comment: 11 figures, 8 page
Current Dissipation in Thin Superconducting Wires: Accurate Numerical Evaluation Using the String Method
Current dissipation in thin superconducting wires is numerically evaluated by
using the string method, within the framework of time-dependent Ginzburg-Landau
equation with a Langevin noise term. The most probable transition pathway
between two neighboring current-carrying metastable states, continuously
linking the Langer-Ambegaokar saddle-point state to a state in which the order
parameter vanishes somewhere, is found numerically. We also give a numerically
accurate algorithm to evaluate the prefactors for the rate of current-reducing
transitions.Comment: 25 pages, 5 figure
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