2,563 research outputs found
Observations of copolar correlation coefficient through a bright band at vertical incidence
Includes bibliographical references (page 52).This paper discusses an application of polarimetric measurements at vertical incidence. In particular, the correlation coefficients between linear copolar components are examined, and measurements obtained with the NSSL's and NCAR's polarimetric radars are presented. The data are from two well-defined bright bands. A sharp decrease of the correlation coefficient, confined to a height interval of a few hundred meters, marks the arttom of the bright band
Growth Stress Induced Tunability of Dielectric Constant in Thin Films
It is demonstrated here that growth stress has a substantial effect on the
dielectric constant of zirconia thin films. The correct combination of
parameters - phase, texture and stress - is shown to yield films with high
dielectric constant and best reported equivalent oxide thickness of 0.8 nm. The
stress effect on dielectric constant is twofold, firstly, by the effect on
phase transitions and secondly by the effect on interatomic distances. We
discuss and explain the physical mechanisms involved in the interplay between
the stress, phase changes and the dielectric constant in detail.Comment: 11 pages, 5 figure
Inverse beta decay reaction in Th and U fission antineutrino flux
Energy spectra of antineutrinos coming from Th and U
neutron-induced fission are calculated, relevant inverse beta decay
positron spectra and total cross sections are
found. This study is stimulated by a hypothesis that a self-sustained nuclear
chain reaction is burning at the center of the Earth ("Georeactor"). The
Georeactor, according to the author of this idea, provides energy necessary to
sustain the Earth's magnetic field. The Georeactor's nuclear fuel is U
and, probably, Th and U. Results of present study may appear to
be useful in future experiments aimed to test the Georector hypothesis and to
estimate its fuel components as a part of developments in geophysics and
astrophysics based on observations of low energy antineutrinos in Nature.Comment: 6 pages in LaTeX and 2 ps figures. Submitted to Physics of Atomic
Nucle
Examining Granular Computing from a Modeling Perspective
In this paper, we use a set of unified components to conduct granular modeling for problem solving paradigms in several fields of computing. Each identified component may represent a potential research direction in the field of granular computing. A granular computing model for information analysis is proposed. The model may suggest that granular computing is an instrument for implementing perception based computing based on numeric computing. In addition, a novel granular language modeling technique is proposed for information extraction from web pages. This paper also suggests that the study of data mining in the framework of granular computing may address the issues of interpretability and usage of discovered patterns
Biomedical Relationship Extraction from Literature Based on Bio-Semantic Token Subsequences
Relationship Extraction (RE) from biomedical literature is an important and challenging problem in both text mining and bioinformatics. Although various approaches have been proposed to extract protein?protein interaction types, their accuracy rates leave a large room for further exploring. In this paper, two supervised learning algorithms based on newly defined bio-semantic token subsequence are proposed for multi-class biomedical relationship classification. The first approach calculates a bio-semantic token subsequence kernel , whereas the second one explicitly extracts weighted features from bio-semantic token subsequences. The two proposed approaches outperform several alternatives reported in literature on multi-class protein?protein interaction classification
On the Mass Eigenstate Composition of the 8B Neutrinos from the Sun
The present data of gallium experiments provide indirectly the only
experimental limit on the fraction of mass eigenstate for the B
neutrinos from the Sun. However, if to use the experimental data alone, the
fraction of and, consequently, still is allowed to
be varied within a rather broad range. The further experimental efforts are
needed to clear this point.Comment: 13 pages, 1 figure, 1 table. Corrected version, published in
JCAP04(2007)00
Quantum versus Semiclassical Description of Selftrapping: Anharmonic Effects
Selftrapping has been traditionally studied on the assumption that
quasiparticles interact with harmonic phonons and that this interaction is
linear in the displacement of the phonon. To complement recent semiclassical
studies of anharmonicity and nonlinearity in this context, we present below a
fully quantum mechanical analysis of a two-site system, where the oscillator is
described by a tunably anharmonic potential, with a square well with infinite
walls and the harmonic potential as its extreme limits, and wherein the
interaction is nonlinear in the oscillator displacement. We find that even
highly anharmonic polarons behave similar to their harmonic counterparts in
that selftrapping is preserved for long times in the limit of strong coupling,
and that the polaronic tunneling time scale depends exponentially on the
polaron binding energy. Further, in agreement, with earlier results related to
harmonic polarons, the semiclassical approximation agrees with the full quantum
result in the massive oscillator limit of small oscillator frequency and strong
quasiparticle-oscillator coupling.Comment: 10 pages, 6 figures, to appear in Phys. Rev.
Unique Factorization For Tensor Products of Parabolic Verma Modules
Let be a symmetrizable Kac-Moody Lie algebra with Cartan
subalgebra . We prove a unique factorization property for tensor
products of parabolic Verma modules. More generally, we prove unique
factorization for products of characters of parabolic Verma modules when
restricted to certain subalgebras of . These include fixed point
subalgebras of under subgroups of diagram automorphisms of
and twisted graph automorphisms in the affine case.Comment: 20 page
Development of a Beneficiation Flow Sheet for Processing Silica Sand from Chertala Area of kerala
The silica sand from Chertala area of Alappuzha district has been reported to be of good quality. Presently, it is mined and transported to destinations inside and outside the State without any processing. A project on beneficiat-ion/ value addition of this sand was taken up as per the request from Directorate of Industries and Commerce, Govt. of Kerala.
Objective of the project is to develop a flow sheet for the total utilization of all fractions of this sand. The aim is to value add the same to produce special grade glass making sand according to BIS specifications (IS:488-1980), a suitable fraction for foundry application as per 1S:3018- 1977 and also to recover the finer fractions of sand and heavy minerals which are below 180,um and consti-tutes about 14% by weight. However, only the first two objectives are covered in the present work
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