554 research outputs found
X-CNN: Cross-modal Convolutional Neural Networks for Sparse Datasets
In this paper we propose cross-modal convolutional neural networks (X-CNNs),
a novel biologically inspired type of CNN architectures, treating gradient
descent-specialised CNNs as individual units of processing in a larger-scale
network topology, while allowing for unconstrained information flow and/or
weight sharing between analogous hidden layers of the network---thus
generalising the already well-established concept of neural network ensembles
(where information typically may flow only between the output layers of the
individual networks). The constituent networks are individually designed to
learn the output function on their own subset of the input data, after which
cross-connections between them are introduced after each pooling operation to
periodically allow for information exchange between them. This injection of
knowledge into a model (by prior partition of the input data through domain
knowledge or unsupervised methods) is expected to yield greatest returns in
sparse data environments, which are typically less suitable for training CNNs.
For evaluation purposes, we have compared a standard four-layer CNN as well as
a sophisticated FitNet4 architecture against their cross-modal variants on the
CIFAR-10 and CIFAR-100 datasets with differing percentages of the training data
being removed, and find that at lower levels of data availability, the X-CNNs
significantly outperform their baselines (typically providing a 2--6% benefit,
depending on the dataset size and whether data augmentation is used), while
still maintaining an edge on all of the full dataset tests.Comment: To appear in the 7th IEEE Symposium Series on Computational
Intelligence (IEEE SSCI 2016), 8 pages, 6 figures. Minor revisions, in
response to reviewers' comment
Enhancement of shot noise due to the fluctuation of Coulomb interaction
We have developed a theoretical formalism to investigate the contribution of
fluctuation of Coulomb interaction to the shot noise based on Keldysh
non-equilibrium Green's function method. We have applied our theory to study
the behavior of dc shot noise of atomic junctions using the method of
nonequilibrium Green's function combined with the density functional theory
(NEGF-DFT). In particular, for atomic carbon wire consisting 4 carbon atoms in
contact with two Al(100) electrodes, first principles calculation within
NEGF-DFT formalism shows a negative differential resistance (NDR) region in I-V
curve at finite bias due to the effective band bottom of the Al lead. We have
calculated the shot noise spectrum using the conventional gauge invariant
transport theory with Coulomb interaction considered explicitly on the Hartree
level along with exchange and correlation effect. Although the Fano factor is
enhanced from 0.6 to 0.8 in the NDR region, the expected super-Poissonian
behavior in the NDR regionis not observed. When the fluctuation of Coulomb
interaction is included in the shot noise, our numerical results show that the
Fano factor is greater than one in the NDR region indicating a super-Poissonian
behavior
The covertisation of norms in contact situations : The influence of the nonnative speaker on native speaker behaviour
Recombination events. a) Detailed information of 2087 recombination events detected in TcTS gene family. b) Summary of number and percentage of newly annotated TcTS and previously annotated TcTS participating in recombination events as recombinant product, major donor or minor donor. (XLSX 549 kb
Bulk Cr tips for scanning tunneling microscopy and spin-polarized scanning tunneling microscopy
A simple, reliable method for preparation of bulk Cr tips for Scanning
Tunneling Microscopy (STM) is proposed and its potentialities in performing
high-quality and high-resolution STM and Spin Polarized-STM (SP-STM) are
investigated. Cr tips show atomic resolution on ordered surfaces. Contrary to
what happens with conventional W tips, rest atoms of the Si(111)-7x7
reconstruction can be routinely observed, probably due to a different
electronic structure of the tip apex. SP-STM measurements of the Cr(001)
surface showing magnetic contrast are reported. Our results reveal that the
peculiar properties of these tips can be suited in a number of STM experimental
situations
Wrapped Magnetized Branes: Two Alternative Descriptions?
We discuss two inequivalent ways for describing magnetized D-branes wrapped N
times on a torus T^2. The first one is based on a non-abelian gauge bundle
U(N), while the second one is obtained by means of a Narain T-duality
transformation acting on a theory with non-magnetized branes. We construct in
both descriptions the boundary state and the open string vertices and show that
they give rise to different string amplitudes. In particular, the description
based on the gauge bundle has open string vertex operators with momentum
dependent Chan-Paton factors.Comment: 60 pages, LaTe
Symmetry Breaking with the SCAN Density Functional Describes Strong Correlation in the Singlet Carbon Dimer
The SCAN (strongly constrained and appropriately normed) meta-generalized
gradient approximation (meta-GGA), which satisfies all 17 exact constraints
that a meta-GGA can satisfy, accurately describes equilibrium bonds that are
normally correlated. With symmetry breaking, it also accurately describes some
sd equilibrium bonds that are strongly correlated. While sp equilibrium bonds
are nearly always normally correlated, the C2 singlet ground state is known to
be a rare case of strong correlation in an sp equilibrium bond. Earlier work
that calculated atomization energies of the molecular sequence B2, C2, O2, and
F2 in the local spin density approximation (LSDA), the Perdew-Burke-Ernzerhof
(PBE) GGA, and the SCAN meta-GGA, without symmetry breaking in the molecule,
found that only SCAN was accurate enough to reveal an anomalous under-binding
for C2. This work shows that spin symmetry breaking in singlet C2, the
appearance of net up- and down-spin densities on opposite sides (not ends) of
the bond, corrects that under-binding, with a small SCAN atomization-energy
error more like that of the other three molecules, suggesting that
symmetry-breaking with an advanced density functional might reliably describe
strong correlation. This article also discusses some general aspects of
symmetry breaking, and the insights into strong correlation that
symmetry-breaking can bring.Comment: 10 pages, 3 figures, 1 Tabl
The holomorphic anomaly for open string moduli
We complete the holomorphic anomaly equations for topological strings with
their dependence on open moduli. We obtain the complete system by standard path
integral arguments generalizing the analysis of BCOV (Commun. Math. Phys. 165
(1994) 311) to strings with boundaries. We study both the anti-holomorphic
dependence on open moduli and on closed moduli in presence of Wilson lines. By
providing the compactification a' la Deligne-Mumford of the moduli space of
Riemann surfaces with boundaries, we show that the open holomorphic anomaly
equations are structured on the (real codimension one) boundary components of
this space.Comment: 1+14 pages, 6 figures! v2: ref. added v3: section 4 expanded, 1+17
pages, 11 figures!!, to be publ. in JHE
Electronic structure investigation of CeB6 by means of soft X-ray scattering
The electronic structure of the heavy fermion compound CeB6 is probed by
resonant inelastic soft X-ray scattering using photon energies across the Ce 3d
and 4d absorption edges. The hybridization between the localized 4f orbitals
and the delocalized valence-band states is studied by identifying the different
spectral contributions from inelastic Raman scattering and normal fluorescence.
Pronounced energy-loss structures are observed below the elastic peak at both
the 3d and 4d thresholds. The origin and character of the inelastic scattering
structures are discussed in terms of charge-transfer excitations in connection
to the dipole allowed transitions with 4f character. Calculations within the
single impurity Anderson model with full multiplet effects are found to yield
consistent spectral functions to the experimental data.Comment: 9 pages, 4 figures, 1 table,
http://link.aps.org/doi/10.1103/PhysRevB.63.07510
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