9,596 research outputs found
Partial regularity of suitable weak solutions to the multi-dimensional generalized magnetohydrodynamics equations
In this paper, we are concerned with the partial regularity of the suitable
weak solutions to the fractional MHD equations in for
. In comparison with the work of the 3D fractional Navier-Stokes
equations obtained by Tang and Yu in [24, Commun. Math. Phys. 334: 1455--1482,
2015], our results include their endpoint case and the external
force belongs to more general parabolic Morrey space. Moreover, we prove some
interior regularity criteria just via the scaled mixed norm of the velocity for
the suitable weak solutions to the fractional MHD equations.Comment: 33 page
Containment Control of Linear Multi-Agent Systems with Multiple Leaders of Bounded Inputs Using Distributed Continuous Controllers
This paper considers the containment control problem for multi-agent systems
with general linear dynamics and multiple leaders whose control inputs are
possibly nonzero and time varying. Based on the relative states of neighboring
agents, a distributed static continuous controller is designed, under which the
containment error is uniformly ultimately bounded and the upper bound of the
containment error can be made arbitrarily small, if the subgraph associated
with the followers is undirected and for each follower there exists at least
one leader that has a directed path to that follower. It is noted that the
design of the static controller requires the knowledge of the eigenvalues of
the Laplacian matrix and the upper bounds of the leaders' control inputs. In
order to remove these requirements, a distributed adaptive continuous
controller is further proposed, which can be designed and implemented by each
follower in a fully distributed fashion. Extensions to the case where only
local output information is available are discussed.Comment: 16 pages, 4 figures. arXiv admin note: text overlap with
arXiv:1312.737
A new Coherent-Entangled state generated by an asymmetric beam splitter and its applications
A new kind of tripartite non-symmetric coordinate coherent-entangled state
(TNCCES) is proposed which exhibits the properties of
both coherence and entanglement and makes up a new quantum mechanical
representation.We investigate some properties of TNCCES such as completeness
and orthogonality which prove it is just a tripartite complete continuous
coordinate base. A protocol for generating TNCCES is proposed using asymmetric
beam splitter. And in application of TNCCES, we find its corresponding Wigner
operator and carry out its marginal distribution form; further a new tripartite
entangled squeezed operator is also presented. The multipartite CES and its
generation are also disussed
Anisotropic thermal expansion and thermomechanic properties of monolayer -Te
Recently, -Te (atomically 2D tellurium) with rectangular crystal
structure has been synthesized successfully on highly oriented pyrolytic
graphite substrates by using molecular beam epitaxy. It has been found
possessing remarkable properties such as ultralow lattice thermal conductivity
and high thermoelectric efficiency. Based on the first-principles calculations,
we study the thermal expansion and thermomechanic properties of the
experimental phase monolayer -Te, using quasiharmonic approach. It is
found -Te shows large positive thermal expansion at elevated
temperature, while the linear thermal expansion coefficient is negative along a
direction at very low temperature. The linear thermal expansion coefficient
along b direction is 4.9*10 K at 500 K, which is considerably
large in 2D materials. -Te exhibits strong in-plane anisotropy,
including thermal expansion, 2D elastic moduli and Poisson's ratios. However,
the elastic moduli, Poisson's ratios and the in-plane anisotropy are weakened
with increasing temperature, and the variations are dominated by the
generalized mode Gr\"{u}neisen parameters.Comment: 25 pages, 7 figures, 14 formula
Remarks on the singular set of suitable weak solutions to the 3D Navier-Stokes equations
In this paper, let denote the possible interior singular set of
suitable weak solutions of the 3D Navier-Stokes equations. We improve the known
upper box-counting dimension of this set from in [24]
to . It is also shown that
, which
extends the previous corresponding results concerning the improvement of the
classical Caffarelli-Kohn-Nirenberg theorem by a logarithmic factor in Choe and
Lewis [3, J. Funct. Anal., 175: 348-369, 2000] and in Choe and Yang et al. [4,
Comm. Math. Phys, 336: 171-198, 2015]. The proof is inspired by a new
-regularity criterion proved by Guevara and Phuc in [7, Calc. Var.
56:68, 2017].Comment: In this version, Theorem 1.3 and its proof are revised. The reason
for the modification of Theorem 1.3 is to answer a issue proposed by the
reviewer. An author is adde
Neural networks for stock price prediction
Due to the extremely volatile nature of financial markets, it is commonly
accepted that stock price prediction is a task full of challenge. However in
order to make profits or understand the essence of equity market, numerous
market participants or researchers try to forecast stock price using various
statistical, econometric or even neural network models. In this work, we survey
and compare the predictive power of five neural network models, namely, back
propagation (BP) neural network, radial basis function (RBF) neural network,
general regression neural network (GRNN), support vector machine regression
(SVMR), least squares support vector machine regresssion (LS-SVMR). We apply
the five models to make price prediction of three individual stocks, namely,
Bank of China, Vanke A and Kweichou Moutai. Adopting mean square error and
average absolute percentage error as criteria, we find BP neural network
consistently and robustly outperforms the other four models.Comment: 13 pages, 3 figures, 4 table
Recommended from our members
Electron Tomography: Electron Tomography: A Three-Dimensional Analytic Tool for Hard and Soft Materials Research (Adv. Mater. 38/2015)
Blur Robust Optical Flow using Motion Channel
It is hard to estimate optical flow given a realworld video sequence with
camera shake and other motion blur. In this paper, we first investigate the
blur parameterization for video footage using near linear motion elements. we
then combine a commercial 3D pose sensor with an RGB camera, in order to film
video footage of interest together with the camera motion. We illustrates that
this additional camera motion/trajectory channel can be embedded into a hybrid
framework by interleaving an iterative blind deconvolution and warping based
optical flow scheme. Our method yields improved accuracy within three other
state-of-the-art baselines given our proposed ground truth blurry sequences;
and several other realworld sequences filmed by our imaging system.Comment: Preprint of our paper accepted by Neurocomputin
Tests for CPT sum rule and U-spin violation in Time-dependent CP violation of and
Recent LHCb data for time-dependent CP violation in
and show deviations from theoretical predictions. Besides
their central values for , and
violate quantum mechanic CPT invariant
sum rule (CPT sum rule) prediction of (LHCb data imply
the sum to be .), their values for and also
show large violation of SU(3) or its U-spin sub-group symmetry (SU(3)/U)
relation (LHCb
data imply the ratio of left-side to right-side to be .) . The
LHCb results need to be further confirmed to be taken seriously. We suggest to
use time-dependent CP violation in
to further test the CPT sum rule. Assuming that the sum rule holds, we propose
that violation of the SU(3)/U relation may indicate a large FSI phase
difference in the and re-scattering. We suggest several
other U-spin pairs of decays to further test SU(3)/U relations.Comment: 12 pages, 1 figure; ACP of updated to the
latest HFAG average, figures slightly changed, a few comments and refs adde
A High-contrast Imaging Algorithm: Optimized Image Rotation and Subtraction
Image Rotation and Subtraction (IRS) is a high-contrast imaging technique
which can be used to suppress the speckles noise and facilitate the direct
detection of exoplanets. IRS is different from Angular Differential Imaging
(ADI), in which it will subtract a copy of the image with 180 degrees rotated
around its PSF center, rather than the subtraction of the median of all of the
PSF images. Since the planet itself will be rotated to the other side of the
PSF, IRS does not suffer from planet self-subtraction. In this paper, we have
introduced an optimization algorithm to IRS (OIRS), which can provide an extra
contrast gain at small angular separations. The performance of OIRS has been
demonstrated with ADI data. We then made a comparison of the signal to noise
ratio (S/N) achieved by algorithms of locally optimized combination of images
(LOCI) and OIRS. Finally we found that OIRS algorithm can deliver a better S/N
for small angular separations.Comment: 18 pages, 8 eps figures, 1 table, accepted for publication in The
Astrophysical Journalon on Jan. 10th, 201
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