48,068 research outputs found
Using Qualitative Hypotheses to Identify Inaccurate Data
Identifying inaccurate data has long been regarded as a significant and
difficult problem in AI. In this paper, we present a new method for identifying
inaccurate data on the basis of qualitative correlations among related data.
First, we introduce the definitions of related data and qualitative
correlations among related data. Then we put forward a new concept called
support coefficient function (SCF). SCF can be used to extract, represent, and
calculate qualitative correlations among related data within a dataset. We
propose an approach to determining dynamic shift intervals of inaccurate data,
and an approach to calculating possibility of identifying inaccurate data,
respectively. Both of the approaches are based on SCF. Finally we present an
algorithm for identifying inaccurate data by using qualitative correlations
among related data as confirmatory or disconfirmatory evidence. We have
developed a practical system for interpreting infrared spectra by applying the
method, and have fully tested the system against several hundred real spectra.
The experimental results show that the method is significantly better than the
conventional methods used in many similar systems.Comment: See http://www.jair.org/ for any accompanying file
Hawking Radiation of an Arbitrarily Accelerating Kinnersley Black Hole: Spin-Acceleration Coupling Effect
The Hawking radiation of Weyl neutrinos in an arbitrarily accelerating
Kinnersley black hole is investigated by using a method of the generalized
tortoise coordinate transformation. Both the location and temperature of the
event horizon depend on the time and on the angles. They coincide with previous
results, but the thermal radiation spectrum of massless spinor particles
displays a kind of spin-acceleration coupling effect.Comment: 8 pages, no figure, revtex 4.0, revisted version with typesetting
errors and misprint correcte
Bagging evolutionary feature extraction algorithm for classification
Author name used in this publication: David ZhangBiometrics Research Centre, Department of ComputingVersion of RecordPublishe
Tracers of chromospheric structure. I. CaII HK emission distribution of 13000 F, G and K stars in SDSS DR7 spectroscopic sample
We present chromospheric activity index measurements for over
13,000 F, G and K disk stars with high signal-to-noise ratio ( 60) spectra
in the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) spectroscopic
sample. A parameter S is defined as the difference between
and a `zero' emission line fitted by several of the most inactive stars. The
indices of subgiant stars tend to be much lower than dwarfs, which
provide a way to distinguish dwarfs and giants with relatively low resolution
spectra. Cooler stars are generally more active and display a larger scatter
than hotter stars. Stars associated with the thick disk are in general less
active than those of the thin disk. The fraction of K dwarfs that are active
drops with vertical distance from the Galactic plane. Metallicity affects
measurements differently among F, G and K dwarfs in this sample.
Using the open clusters NGC 2420, M67 and NGC6791 as calibrations, ages of most
field stars in this SDSS sample range from 3-8 Gyr.Comment: 9 pages, 11 figures, AJ, 2013, 145, 14
Non-existence of New Quantum Ergosphere Effect of a Vaidya-type Black Hole
Hawking evaporation of Dirac particles and scalar fields in a Vaidya-type
black hole is investigated by the method of generalized tortoise coordinate
transformation. It is shown that Hawking radiation of Dirac particles does not
exist for components but for components in any
Vaidya-type black holes. Both the location and the temperature of the event
horizon change with time. The thermal radiation spectrum of Dirac particles is
the same as that of Klein-Gordon particles. We demonstrates that there is no
new quantum ergosphere effect in the thermal radiation of Dirac particles in
any spherically symmetry black holes.Comment: Latex, 9 pages, no figure, submitted to Mod. Phys. Lett.
Two Kinds of Iterative Solutions for Generalized Sombrero-shaped Potential in -dimensional Space
Based on two different iteration procedures the groundstate wave functions
and energies for N-dimensional generalized Sombrero-shaped potentials are
solved. Two kinds of trial functions for the iteration procedure are defined.
The iterative solutions are convergent nicely to consistent results for
different choices of iteration procedures and trial functions.Comment: 16 pages, 3 figure
Relations Between Low-lying Quantum Wave Functions and Solutions of the Hamilton-Jacobi Equation
We discuss a new relation between the low lying Schroedinger wave function of
a particle in a one-dimentional potential V and the solution of the
corresponding Hamilton-Jacobi equation with -V as its potential. The function V
is , and can have several minina (V=0). We assume the problem to be
characterized by a small anhamornicity parameter and a much smaller
quantum tunneling parameter between these different minima.
Expanding either the wave function or its energy as a formal double power
series in and , we show how the coefficients of
in such an expansion can be expressed in terms of definite
integrals, with leading order term determined by the classical solution of the
Hamilton-Jacobi equation. A detailed analysis is given for the particular
example of quartic potential .Comment: LaTex, 48 pages, no figur
Chemical composition of 90 F and G disk dwarfs
High resolution, high S/N spectra have been obtained for a sample of 90 F and
G main-sequence disk stars covering the metallicity range -1.0 < [Fe/H] < +0.1,
and have been analysed in a parallel way to the work of Edvardsson et al.
(1993). Effective temperatures are based on the Alonso et al. (1996)
calibration of color indices and surface gravities are calculated from
Hipparcos parallaxes, which also allow more accurate ages to be calculated. In
addition, more reliable kinematical parameters are derived from Hipparcos
distances and proper motions. Finally, a larger spectral coverage, 5600 - 8800
A, makes it possible to improve the abundance accuracy by studying more lines
and to discuss several elements not included in the work of Edvardsson et al.
The present paper provides the data and discusses some general results of the
abundance survey. A group of stars in the metallicity range of -1.0 < [Fe/H] <
-0.6 having a small mean Galactocentric distance in the stellar orbits, Rm < 7
kpc, are shown to be older than the other disk stars and probably belong to the
thick disk. Excluding these stars, a slight decreasing trend of [Fe/H] with
increasing Rm and age is found, but a large scatter in [Fe/H] (up to 0.5 dex)
is present at a given age and Rm. The derived trends of O, Mg, Si, Ca, Ti, Ni
and Ba as a function of [Fe/H] agree rather well with those of Edvardsson et
al., but the overabundance of Na and Al for metal-poor stars found in their
work is not confirmed. Furthermore, the Galactic evolution of elements not
included in Edvardsson et al., K, V and Cr, is studied.Comment: 16 pages with 10 figures. Accepted for publication in A&A
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