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Modular feature selection using relative importance factors
Feature selection plays an important role in finding relevant or irrelevant features in classification. Genetic algorithms (GAs) have been used as conventional methods for classifiers to adaptively evolve solutions for classification problems. In this paper, we explore the use of feature selection in modular GA-based classification. We propose a new feature selection technique, Relative Importance Factor (RIF), to find irrelevant features in the feature space of each module. By removing these features, we aim to improve classification accuracy and reduce the dimensionality of classification problems. Benchmark classification data sets are used to evaluate the proposed approaches. The experiment results show that RIF can be used to determine irrelevant features and help achieve higher classification accuracy with the feature space dimension reduced. The complexity of the resulting rule sets is also reduced which means the modular classifiers with irrelevant features removed will be able to classify data with a higher throughput
Spectral functions and optical conductivity of spinless fermions on a checkerboard lattice
We study the dynamical properties of spinless fermions on the checkerboard
lattice. Our main interest is the limit of large nearest-neighbor repulsion
as compared with hopping . The spectral functions show broad low-energy
excitation which are due to the dynamics of fractionally charged excitations.
Furthermore, it is shown that the fractional charges contribute to the
electrical current density.Comment: 9 Pages, 9 Figure
Theory for Gossamer and Resonating Valence Bond Superconductivity
We use an effective Hamiltonian for two-dimensional Hubbard model including
an antiferromagnetic spin-spin coupling term to study recently proposed
gossamer superconductivity. We formulate a renormalized mean field theory to
approximately take into account the strong correlation effect in the partially
projected Gutzwiller wavefucntions. At the half filled, there is a first order
phase transition to separate a Mott insulator at large Coulomb repulsion U from
a gossamer superconductor at small U. Away from the half filled,the Mott
insulator is evolved into an resonating valence bond state, which is
adiabatically connected to the gossamer superconductor.Comment: 10 pages, 13 figure
Aharonov-Casher phase and persistent current in a polyacetylene ring
We investigate a polyacetylene ring in an axially symmetric, static electric
field with a modified SSH Hamiltonian of a polyacetylene chain. An effective
gauge potential of the single electron Hamiltonian due to spin-field
interaction is obtained and it results in a Fr\"{o}hlich's type of
superconductivity equivalent to the effect of travelling lattice wave. The
total energy as well as the persistent current density are shown to be a
periodic function of the flux of the gauge field embraced by the polyacetylene
ring.Comment: 12 pages, 5 figure
Compensation of compliance errors in parallel manipulators composed of non-perfect kinematic chains
The paper is devoted to the compliance errors compensation for parallel
manipulators under external loading. Proposed approach is based on the
non-linear stiffness modeling and reduces to a proper adjusting of a target
trajectory. In contrast to previous works, in addition to compliance errors
caused by machining forces, the problem of assembling errors caused by
inaccuracy in the kinematic chains is considered. The advantages and practical
significance of the proposed approach are illustrated by examples that deal
with groove milling with Orthoglide manipulator.Comment: Advances in Robot Kinematics, France (2012
Dirac Cosmology and the Acceleration of the Contemporary Universe
A model is suggested to unify the Einstein GR and Dirac Cosmology. There is
one adjusted parameter in our model. After adjusting the parameter
in the model by using the supernova data, we have calculated the gravitational
constant and the physical quantities of , and by using the present day quantities as the initial conditions and
found that the equation of state parameter equals to -0.83, the
ratio of the density of the addition creation and the
ratio of the density of the matter including multiplication creation, radiation
and normal matter at present. The results are self-consistent
and in good agreement with present knowledge in cosmology. These results
suggest that the addition creation and multiplication creation in Dirac
cosmology play the role of the dark energy and dark matter.Comment: 13 pages, 8 figure
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