3,836 research outputs found
Theory of amplification of sound (acoustic phonons) by absorption of laser radiation in quantum wires with parabolic potential
Based on the quantum transport equation for the electron-phonon system, the
absorption coefficient of sound (acoustic phonons) by absorption of a laser
radiation in quantum wires with parabolic potential is calculated for the case
of monophoton absorption and the case of multiphoton absorption. Analytical
expressions and conditions for the absorption coefficient of sound are
obtained. Differences between the two cases of monophoton absorption and of
multiphoton absorption are discussed; numerical computations and plots are
carried out for a GaAs/GaAsAl quantum wire. The results are compared with bulk
semiconductors and quantum wells.Comment: 7 pages, 1 figur
Energy conservation for inhomogeneous incompressible and compressible Euler equations
Energy conservations are studied for inhomogeneous incompressible and
compressible Euler equations with general pressure law in a torus or a bounded
domain. We provide sufficient conditions for a weak solution to conserve the
energy. By exploiting a suitable test function, the spatial regularity for the
density is only required to be of order in the incompressible case, and
of order in the compressible case. When the density is constant, we
recover the existing results for classical incompressible Euler equation.Comment: The new version deals with general pressure law for compressible
equations. By using a new test function, we allow the density to be zero
instead of excluding completely vacuum. Required regularities for the density
in the compressible case are also reduce
Global estimates for quasilinear parabolic equations on Reifenberg flat domains and its applications to Riccati type parabolic equations with distributional data
In this paper, we prove global weighted Lorentz and Lorentz-Morrey estimates
for gradients of solutions to the quasilinear parabolic equations:
in a bounded
domain , under minimal regularity
assumptions on the boundary of domain and on nonlinearity . Then results
yields existence of a solution to the Riccati type parabolic equations:
where and is a bounded Radon
measure.Comment: to appear Calculus of Variations and Partial Differential Equation
Gradient estimates for singular quasilinear elliptic equations with measure data
In this paper, we prove -estimates for gradients of solutions to
singular quasilinear elliptic equations with measure data
in a bounded domain
, where , and is a Radon measure in Comment: 20 pages. arXiv admin note: text overlap with arXiv:1511.0621
A survey of embedding models of entities and relationships for knowledge graph completion
Knowledge graphs (KGs) of real-world facts about entities and their
relationships are useful resources for a variety of natural language processing
tasks. However, because knowledge graphs are typically incomplete, it is useful
to perform knowledge graph completion or link prediction, i.e. predict whether
a relationship not in the knowledge graph is likely to be true. This paper
serves as a comprehensive survey of embedding models of entities and
relationships for knowledge graph completion, summarizing up-to-date
experimental results on standard benchmark datasets and pointing out potential
future research directions.Comment: 13 pages, 2 figures and 6 table
Non-commutative Chern Characters of the C*-Algebras of spheres and quantum spheres
We propose in this paper the construction of non-commutative Chern characters
of the C*-algebras of spheres and quantum spheres. The final computation gives
us a clear relation with the ordinary Z/(2)-graded Chern characters of tori or
their normalizers.Comment: 12 pages, AmSTeX fil
A neural joint model for Vietnamese word segmentation, POS tagging and dependency parsing
We propose the first multi-task learning model for joint Vietnamese word
segmentation, part-of-speech (POS) tagging and dependency parsing. In
particular, our model extends the BIST graph-based dependency parser
(Kiperwasser and Goldberg, 2016) with BiLSTM-CRF-based neural layers (Huang et
al., 2015) for word segmentation and POS tagging. On Vietnamese benchmark
datasets, experimental results show that our joint model obtains
state-of-the-art or competitive performances.Comment: In Proceedings of the 17th Annual Workshop of the Australasian
Language Technology Association (ALTA 2019
Rationality of almost simple algebraic groups
We prove the stable rationality of almost simple algebraic groups, the
connected components of the Dynkin diagram of anisotropic kernel of which
contain at most two vertices. The (stable) rationality of many isotropic almost
simple groups with small anisotropic kernel and some related results over
-adic and arbitrary fields are discussed.Comment: originally the manuscript has been circulated since March 1995, LaTe
A Fast and Accurate Vietnamese Word Segmenter
We propose a novel approach to Vietnamese word segmentation. Our approach is
based on the Single Classification Ripple Down Rules methodology (Compton and
Jansen, 1990), where rules are stored in an exception structure and new rules
are only added to correct segmentation errors given by existing rules.
Experimental results on the benchmark Vietnamese treebank show that our
approach outperforms previous state-of-the-art approaches JVnSegmenter,
vnTokenizer, DongDu and UETsegmenter in terms of both accuracy and performance
speed. Our code is open-source and available at:
https://github.com/datquocnguyen/RDRsegmenter.Comment: In Proceedings of the 11th International Conference on Language
Resources and Evaluation (LREC 2018), to appea
Plasmon modes in graphene-GaAs heterostructures
We investigate the plasmon dispersion relation and damping rate of collective
excitations in a double-layer system consisting of bilayer graphene and GaAs
quantum well, separated by a distance, at zero temperature with no interlayer
tunneling. We use the random-phase-approximation dielectric function and take
into account the nonhomogeneity of the dielectric background of the system. We
show that the plasmon frequencies and damping rates depend considerably on
interlayer correlation parameters, electron densities and dielectric constants
of the contacting media.Comment: 7 pages, 7 figure
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