3,399 research outputs found
Herd Behaviors in Financial Markets
We investigate the herd behavior of returns for the yen-dollar exchange rate
in the Japanese financial market. It is obtained that the probability
distribution of returns satisfies the power-law behavior with the exponents (the time interval
one minute) and 3.36( one day). The informational cascade regime appears
in the herding parameter at one minute, while it occurs no
herding at one day. Especially, we find that the distribution of
normalized returns shows a crossover to a Gaussian distribution at one time
step day.Comment: 15 pages, 6 figure
Scarred Resonances and Steady Probability Distribution in a Chaotic Microcavity
We investigate scarred resonances of a stadium-shaped chaotic microcavity. It
is shown that two components with different chirality of the scarring pattern
are slightly rotated in opposite ways from the underlying unstable periodic
orbit, when the incident angles of the scarring pattern are close to the
critical angle for total internal reflection. In addition, the correspondence
of emission pattern with the scarring pattern disappears when the incident
angles are much larger than the critical angle. The steady probability
distribution gives a consistent explanation about these interesting phenomena
and makes it possible to expect the emission pattern in the latter case.Comment: 4 pages, 5 figure
Two-dimensional imaging of edge-localized modes in KSTAR plasmas unperturbed and perturbed by n=1 external magnetic fields
The temporal evolution of edge-localized modes (ELMs) has been studied using a 2-D electron cyclotron emission imaging system in the KSTAR tokamak. The ELMs are observed to evolve in three distinctive stages: the initial linear growth of multiple filamentary structures having a net poloidal rotation, the interim state of regularly spaced saturated filaments, and the final crash through a short transient phase characterized by abrupt changes in the relative amplitudes and distance among filaments. The crash phase, typically consisted of multiple bursts of a single filament, involves a complex dynamics, poloidal elongation of the bursting filament, development of a fingerlike bulge, and fast localized burst through the finger. Substantial alterations of the ELM dynamics, such as mode number, poloidal rotation, and crash time scale, have been observed under external magnetic perturbations with the toroidal mode number n = 1. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.3694842]X1125sciescopu
Electronic structures of ZnCoO using photoemission and x-ray absorption spectroscopy
Electronic structures of ZnCoO have been investigated using
photoemission spectroscopy (PES) and x-ray absorption spectroscopy (XAS). The
Co 3d states are found to lie near the top of the O valence band, with a
peak around eV binding energy. The Co XAS spectrum provides
evidence that the Co ions in ZnCoO are in the divalent Co
() states under the tetrahedral symmetry. Our finding indicates that the
properly substituted Co ions for Zn sites will not produce the diluted
ferromagnetic semiconductor property.Comment: 3 pages, 2 figure
Occlusion-Aware Depth Estimation with Adaptive Normal Constraints
We present a new learning-based method for multi-frame depth estimation from
a color video, which is a fundamental problem in scene understanding, robot
navigation or handheld 3D reconstruction. While recent learning-based methods
estimate depth at high accuracy, 3D point clouds exported from their depth maps
often fail to preserve important geometric feature (e.g., corners, edges,
planes) of man-made scenes. Widely-used pixel-wise depth errors do not
specifically penalize inconsistency on these features. These inaccuracies are
particularly severe when subsequent depth reconstructions are accumulated in an
attempt to scan a full environment with man-made objects with this kind of
features. Our depth estimation algorithm therefore introduces a Combined Normal
Map (CNM) constraint, which is designed to better preserve high-curvature
features and global planar regions. In order to further improve the depth
estimation accuracy, we introduce a new occlusion-aware strategy that
aggregates initial depth predictions from multiple adjacent views into one
final depth map and one occlusion probability map for the current reference
view. Our method outperforms the state-of-the-art in terms of depth estimation
accuracy, and preserves essential geometric features of man-made indoor scenes
much better than other algorithms.Comment: ECCV 202
Properties of Central Caustics in Planetary Microlensing
To maximize the number of planet detections, current microlensing follow-up
observations are focusing on high-magnification events which have a higher
chance of being perturbed by central caustics. In this paper, we investigate
the properties of central caustics and the perturbations induced by them. We
derive analytic expressions of the location, size, and shape of the central
caustic as a function of the star-planet separation, , and the planet/star
mass ratio, , under the planetary perturbative approximation and compare the
results with those based on numerical computations. While it has been known
that the size of the planetary caustic is \propto \sqrt{q}, we find from this
work that the dependence of the size of the central caustic on is linear,
i.e., \propto q, implying that the central caustic shrinks much more rapidly
with the decrease of compared to the planetary caustic. The central-caustic
size depends also on the star-planet separation. If the size of the caustic is
defined as the separation between the two cusps on the star-planet axis
(horizontal width), we find that the dependence of the central-caustic size on
the separation is \propto (s+1/s). While the size of the central caustic
depends both on and q, its shape defined as the vertical/horizontal width
ratio, R_c, is solely dependent on the planetary separation and we derive an
analytic relation between R_c and s. Due to the smaller size of the central
caustic combined with much more rapid decrease of its size with the decrease of
q, the effect of finite source size on the perturbation induced by the central
caustic is much more severe than the effect on the perturbation induced by the
planetary caustic. Abridged.Comment: 5 pages, 4 figures, ApJ accepte
Rhodium-oxide-coated indium tin oxide for enhancement of hole injection in organic light emitting diodes
The authors report the enhancement of hole injection using an RhOx layer between indium tin oxide anodes and 4, 4??? -bis[N-(1-naphtyl)- N -phenyl-amino]biphenyl in organic light-emitting diodes (OLEDs). The operation voltage of OLEDs at 700 cdm2 decreased from 13 to 10 V as the Rh layer changed to RhOx by surface treatment using O2 plasma. Synchrotron radiation photoelectron spectroscopy results showed that the work function increased by 0.2 eV as the Rh layer transformed into RhOx. Thus, the hole injection energy barrier was lowered, reducing the turn-on voltage and increasing the quantum efficiency of OLEDs.open281
Immune-modulation of two BATF3 paralogues in rainbow trout Oncorhynchus mykiss
This work was supported by the Royal Society of Edinburgh and the National Natural Science Foundation of China (Grant Nos., 31511130137 and 31372568). Dr Jun Wang’s visit to the Scottish Fish Immunology Research Centre was funded by the China Scholarship Council (CSC).Peer reviewedPostprin
Traveltime calculations from frequency-domain downward-continuation algorithms
We present a new, fast 3D traveltime calculation algorithm
that employs existing frequency-domain waveequation
downward-continuation software. By modifying
such software to solve for a few complex (rather than
real) frequencies, we are able to calculate not only the
first arrival and the approximately most energetic traveltimes
at each depth point but also their corresponding
amplitudes.We compute traveltimes by either taking
the logarithm of displacements obtained by the oneway
wave equation at a frequency or calculating derivatives
of displacements numerically. Amplitudes are estimated
from absolute value of the displacement at a
frequency.
By using the one-way downgoing wave equation, we
also circumvent generating traveltimes corresponding to
near-surface upcoming head waves not often needed in
migration.We compare the traveltimes computed by our
algorithm with those obtained by picking the most energetic
arrivals from finite-difference solutions of the
one-way wave equation, and show that our traveltime
calculation method yields traveltimes comparable to solutions
of the one-way wave equation. We illustrate the
accuracy of our traveltime algorithm by migrating the
2D IFP Marmousi and the 3D SEG/EAGE salt models.This work was financially supported by National Laboratory
Project of Ministry of Science and Technology, Brain Korea 21
project of theKorea Ministry of Education, and grant No. R03-
2000-000-00003-0 from the Basic Research Program of the
Korea Science & Engineering Foundation
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