936 research outputs found
Creating a low carbon economy through green supply chain management: investigation of willingness-to-pay for green products from a consumerâs perspective
This study investigates how consumersâ willingness-to-pay (WTP) for green products affects the decisions made by the green supply chain players. Through the application of game theory and uncertainty theory, our findings show that a higher consumer WTP for green products usually leads to a higher retail price and market share of green products, which motivates retailers and manufacturers to invest more in green technology. We also find that an increased WTP for green products can spur retailers to reduce the optimal green cost-sharing rate due to the pressure of increasing costs. In addition, we find that retailers are willing to lower the cost sharing rate when the confidence level increases. Regarding the contributions made by this study, it is one of the first to explore the transmission mechanisms involved in the management of the green supply chain by linking consumersâ WTP for green products to strategic decisions made by green supply chain players under conditions of uncertainty. Furthermore, our study could help green supply chain players to optimise the cost sharing mechanisms they use to generate more revenue, due to the increase in WTP for green products, which will in turn help to facilitate a low carbon economy
Power Laws, Precursors and Predictability During Failure
We investigate the dynamics of a modified Burridge-Knopoff model by
introducing a dissipative term to mimic the bursts of acoustic emission (AE)
from rock samples. The model explains many features of the statistics of AE
signals observed in experiments such as the crossover in the exponent value
from relatively small amplitude AE signals to larger regime, and their
dependence on the pulling speed. Significantly, we find that the cumulative
energy dissipated identified with acoustic emission can be used to predict a
major slip event. We also find a data collapse of the acoustic activity for
several major slip events describable by a universal stretched exponential with
corrections in terms of time-to-failure.Comment: 7 pages, 6 figures, Final version with minor change
Scintillation of PSR B1508+55 -- the view from a 10,000-km baseline
We report on the simultaneous Giant Metrewave Radio Telescope (GMRT) and
Algonquin Radio Observatory (ARO) observations at 550-750 MHz of the
scintillation of PSR B1508+55, resulting in a 10,000-km baseline. This
regime of measurement lies between the shorter few 100-1000~km baselines of
earlier multi-station observations and the much longer earth-space baselines.
We measure a scintillation cross-correlation coefficient of , offset from
zero time lag due to a ~s traversal time of the scintillation pattern.
The scintillation time of 135~s is longer, ruling out isotropic as
well as strictly 1D scattering. Hence, the low cross-correlation coefficient is
indicative of highly anisotropic but 2D scattering. The common scintillation
detected on the baseline is confined to low delays of s,
suggesting that this correlation may not be associated with the parabolic
scintillation arc detected at the GMRT. Detection of pulsed echoes and their
direct imaging with the Low Frequency Array (LOFAR) by a different group enable
them to measure a distance of 125~pc to the screen causing these echoes. These
previous measurements, alongside our observations, lead us to propose that
there are at least two scattering screens: the closer 125 pc screen causing the
scintillation arc detected at GMRT, and a screen further beyond causing the
scintillation detected on the GMRT-ARO baseline. We advance the hypothesis that
the 125-pc screen partially resolves the speckle images on the screen beyond
leading to loss of coherence in the scintillation dynamic spectrum, to explain
the low cross-correlation coefficient.Comment: 10 pages, 8 figures, accepted for publication in MNRA
Imaging Inter-Edge State Scattering Centers in the Quantum Hall Regime
We use an atomic force microscope tip as a local gate to study the scattering
between edge channels in a 2D electron gas in the quantum Hall regime. The
scattering is dominated by individual, microscopic scattering centers, which we
directly image here for the first time. The tip voltage dependence of the
scattering indicates that tunneling occurs through weak links and localized
states.Comment: 4 pages, 5 figure
Local Distributions and Rate Fluctuations in a Unified Scaling Law for Earthquakes
A recently proposed unified scaling law for interoccurrence times of
earthquakes [P. Bak et al., Phys. Rev. Lett. {\bf 88}, 178501 (2002)] is
analyzed, both theoretically and with data from Southern California. We
decompose the corresponding probability density into local-instantaneous
distributions, which scale with the rate of earthquake occurrence. The
fluctuations of the rate, characterizing the non-stationarity of the process,
show a doubly power-law distribution and are fundamental to determine the
overall behavior, described by a double power law as well.Comment: 8 text pages but swift to read, 4 figures self-explained. In memoriam
of Per Ba
Quantum Hall fluctuations and evidence for charging in the quantum Hall effect
We find that mesoscopic conductance fluctuations in the quantum Hall regime
in silicon MOSFETs display simple and striking patterns. The fluctuations fall
into distinct groups which move along lines parallel to loci of integer filling
factor in the gate voltage-magnetic field plane. Also, a relationship appears
between the fluctuations on quantum Hall transitions and those found at low
densities in zero magnetic field. These phenomena are most naturally attributed
to charging effects. We argue that they are the first unambiguous manifestation
of interactions in dc transport in the integer quantum Hall effect.Comment: 4 pages RevTeX including 4 postscript bitmapped figure
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