22,044 research outputs found
Customer Concerns about Uncertainty and Willingness to Pay in Leasing Solar Power Systems
Although solar power systems are considered as one of the most promising renewable energy sources, some uncertain factors as well as the high cost could be barriers which create customer resistance. Leasing instead of purchase, as one type of product service system, could be an option to reduce consumer concern on such issues. This study focuses on consumer concerns about uncertainty and willingness to pay for leasing solar power systems. Conjoint analysis method is used to find part worth utilities and estimate gaps of willingness to pay between attribute levels, including various leasing time lengths. The results show the part worth utilities an d relative importance of four major attributes, including leasing time. Among concerns about uncertainties, government subsidy, electricity price, reliability, and rise of new generation solar power systems were found to be significantly related to the additional willingness-to-pay for a shorter leasing time. Cluster analysis is used to identify two groups standing for high and low concerns about uncertainty. People with more concerns tend to pay more for a shorter lease time
A statistical mechanics framework for multi-particle production in high energy reactions
We deduce the particle distributions in particle collisions with
multihadron-production in the framework of mechanical statistics. They are
derived as functions of x, P_T^2 and the rest mass of different species for a
fixed total number of all produced particles, inelasticity and total transverse
energy. For P_T larger than the mass of each particle we get the behaviour
\frac{dn_i}{dP_T} \sim \sqrt{P_T} e^{-\frac{P_T}{T_H}} Values of _\pi,
_K, and _{\bar{p}} in agreement with experiment are found by taking
T_H=180MeV (the Hagedorn temperature).Comment: 9 pages, RevTe
Stochastic self-assembly of incommensurate clusters
We examine the classic problem of homogeneous nucleation and growth by
deriving and analyzing a fully discrete stochastic master equation. Upon
comparison with results obtained from the corresponding mean-field
Becker-D\"{o}ring equations we find striking differences between the two
corresponding equilibrium mean cluster concentrations. These discrepancies
depend primarily on the divisibility of the total available mass by the maximum
allowed cluster size, and the remainder. When such mass incommensurability
arises, a single remainder particle can "emulsify" or "disperse" the system by
significantly broadening the mean cluster size distribution. This finite-sized
broadening effect is periodic in the total mass of the system and can arise
even when the system size is asymptotically large, provided the ratio of the
total mass to the maximum cluster size is finite. For such finite ratios we
show that homogeneous nucleation in the limit of large, closed systems is not
accurately described by classical mean-field mass-action approaches.Comment: 5 pages, 4 figures, 1 tabl
Momentum Distribution for Bosons with Positive Scattering Length in a Trap
The coordinate-momentum double distribution function is calculated in the local density approximation for bosons with
positive scattering length in a trap. The calculation is valid to the first
order of . To clarify the meaning of the result, it is compared for a
special case with the double distribution function of
Wigner.Comment: Latex fil
^{59}Co NMR evidence for charge ordering below T_{CO}\sim 51 K in Na_{0.5}CoO_2
The CoO layers in sodium-cobaltates NaCoO may be viewed as
a spin triangular-lattice doped with charge carriers. The underlying
physics of the cobaltates is very similar to that of the high cuprates.
We will present unequivocal Co NMR evidence that below ,
the insulating ground state of the itinerant antiferromagnet
NaCoO () is induced by charge ordering.Comment: Phys. Rev. Lett. 100 (2008), in press. 4 figure
Deep shower interpretation of the cosmic ray events observed in excess of the Greisen-Zatsepin-Kuzmin energy
We consider the possibility that the ultra-high-energy cosmic ray flux has a
small component of exotic particles which create showers much deeper in the
atmosphere than ordinary hadronic primaries. It is shown that applying the
conventional AGASA/HiRes/Auger data analysis procedures to such exotic events
results in large systematic biases in the energy spectrum measurement. SubGZK
exotic showers may be mis-reconstructed with much higher energies and mimick
superGZK events. Alternatively, superGZK exotic showers may elude detection by
conventional fluorescence analysis techniques.Comment: 22 pages, 5 figure
EXITE2 Observation of the SIGMA Source GRS 1227+025
We report the EXITE2 hard X-ray imaging of the sky around 3C273. A 2h
observation on May 8, 1997, shows a 260 mCrab source detected at
in each of two bands (50-70 and 70-93 keV) and located 30'
from 3C273 and consistent in position with the SIGMA source GRS1227+025. The
EXITE2 spectrum is consistent with a power law with photon index 3 and large
low energy absorption, as indicated by the GRANAT/SIGMA results. No source was
detected in more sensitive followup EXITE2 observations in 2000 and 2001 with
3 upper limits of 190 and 65 mCrab, respectively. Comparison with the
flux detected by SIGMA shows the source to be highly variable, suggesting it
may be non-thermal and beamed and thus the first example of a ``type 2''
(absorbed) Blazar. Alternatively it might be (an unprecedented) very highly
absorbed binary system undergoing accretion disk instability outbursts,
possibly either a magnetic CV, or a black hole X-ray nova.Comment: 12 pages, 4 figures, accepted for publication in Ap
Baryon Magnetic Moments and Proton Spin: A Model with Collective Quark Rotation
We analyse the baryon magnetic moments in a model that relates them to the
parton spins , , , and includes a contribution
from orbital angular momentum. The specific assumption is the existence of a
3-quark correlation (such as a flux string) that rotates with angular momentum
around the proton spin axis. A fit to the baryon magnetic
moments, constrained by the measured values of the axial vector coupling
constants , , yields , , where the error is a theoretical
estimate. A second fit, under slightly different assumptions, gives , with no constraint on . The
model provides a consistent description of axial vector couplings, magnetic
moments and the quark polarization measured in deep
inelastic scattering. The fits suggest that a significant part of the angular
momentum of the proton may reside in a collective rotation of the constituent
quarks.Comment: 16 pages, 3 ps-figures, uses RevTeX. Abstract, Sec. II, III and IV
have been expande
Experimental evidence for a two-gap structure of superconducting NbSe_2: a specific heat study in external magnetic fields
To resolve the discrepancies of the superconducting order parameter in
quasi-two-dimensional NbSe_2, comprehensive specific-heat measurements have
been carried out. By analyzing both the zero-field and mixed-state data with
magnetic fields perpendicular to and parallel to the c axis of the crystal and
using the two-gap model, we conclude that (1) more than one energy scale of the
order parameter is required for superconducting NbSe_2 due to the thermodynamic
consistency; (2)delta_L=1.26 meV and delta_S=0.73 meV are obtained; (3)
N_S(0)/N(0)=11%~20%; (4) The observation of the kink in gamma(H) curve suggests
that the two-gap scenario is more favorable than the anisotropic s-wave model
to describe the gap structure of NbSe_2; and (5)delta_S is more isotropic and
has a three-dimensional-like feature and is located either on the Se or the
bonding Nb Fermi sheets.Comment: 16 pages, 4 figure
General linear dynamics - quantum, classical or hybrid
We describe our recent proposal of a path integral formulation of classical
Hamiltonian dynamics. Which leads us here to a new attempt at hybrid dynamics,
which concerns the direct coupling of classical and quantum mechanical degrees
of freedom. This is of practical as well as of foundational interest and no
fully satisfactory solution of this problem has been established to date.
Related aspects will be observed in a general linear ensemble theory, which
comprises classical and quantum dynamics in the form of Liouville and von
Neumann equations, respectively, as special cases. Considering the simplest
object characterized by a two-dimensional state-space, we illustrate how
quantum mechanics is special in several respects among possible linear
generalizations.Comment: 17 pages; based on invited talks at the conferences DICE2010
(Castiglioncello, Italia, Sept 13-17, 2010) and Quantum Field Theory and
Gravity (Regensburg, Germany, Sept 28 - Oct 1, 2010
- …