title: MESL: Proposal for a Non-volatile Cascadable Magneto-Electric Spin Logic

abstract:
  In the quest for novel, scalable and energy-efficient computing technologies,
many non-charge based logic devices are being explored. Recent advances in
multi-ferroic materials have paved the way for electric field induced low
energy and fast switching of nano-magnets using the magneto-electric (ME)
effect. In this paper, we propose a voltage driven logic-device based on the ME
induced switching of nano-magnets. We further demonstrate that the proposed
logic-device, which exhibits decoupled read and write paths, can be used to
construct a complete logic family including XNOR, NAND and NOR gates. The
proposed logic family shows good scalability with a quadratic dependence of
switching energy with respect to the switching voltage. Further, the proposed
logic-device has better robustness against the effect of thermal noise as
compared to the conventional current driven switching of nano-magnets. A
device-to-circuit level coupled simulation framework, including magnetization
dynamics and electron transport model, has been developed for analyzing the
present proposal. Using our simulation framework, we present energy and delay
results for the proposed Magneto-Electric Spin Logic (MESL) gates.


title:
Short-time diffusion behavior of Brownian particles in confining
  potentials

abstract:
  Diffusion behavior of Brownian particles in confined spaces was studied for
the displacements notably shorter than the confinement size. The confinements,
resembling structure of porous solids, were modeled using a spatially-varying
potential field with an infinitely large potential representing the solid part
and zero potential in the void space. Between them, a smooth transient
mimicking the interaction potential of the tracer molecules with the pore walls
was applied. The respective Smoluchowski equation describing diffusion of
tracer particles in the thus created force field was solved under certain
approximations allowing for a general analytical solution. The time-depended
diffusion coefficient obtained was found to agree with that obtained earlier
using the Fick's diffusion equation, but with a different numerical constant.
Numerical solution of the Smoluchowski equation with selected interaction
potentials was used to clarify the origin of this discrepancy. The conditions
under which the solutions obtained within these two approaches converge were
established.


title:
AC-Conductivity Measure from Heat Production of Free Fermions in
  Disordered Media

abstract:
  We extend [Bru-de Siqueira Pedra-Hertling, J. Math. Phys. 56 (2015) 051901]
in order to study the linear response of free fermions on the lattice within a
(independently and identically distributed) random potential to a macroscopic
electric field that is time- and space-dependent. We obtain the notion of a
macroscopic AC-conductivity measure which only results from the second
principle of thermodynamics. The latter corresponds here to the positivity of
the heat production for cyclic processes on equilibrium states. Its Fourier
transform is a continuous bounded function which is naturally called
(macroscopic) conductivity. We additionally derive Green-Kubo relations
involving time-correlations of bosonic fields coming from current fluctuations
in the system. This is reminiscent of non-commutative central limit theorems.


title: The Markowitz Category

abstract:
  We give an algebraic definition of a Markowitz market and classify markets up
to isomorphism. Given this classification, the theory of portfolio optimization
in Markowitz markets without short selling constraints becomes trivial.
Conversely, this classification shows that, up to isomorphism, there is little
that can be said about a Markowitz market that is not already detected by the
theory of portfolio optimization. In particular, if one seeks to develop a
simplified low-dimensional model of a large financial market using
mean--variance analysis alone, the resulting model can be at most
two-dimensional.


title:
$^{22}$Ne and $^{23}$Na ejecta from intermediate-mass stars: The impact
  of the new LUNA rate for $^{22}$Ne(p,$\gamma$)$^{23}$Na

abstract:
  We investigate the impact of the new LUNA rate for the nuclear reaction
$^{22}$Ne$(p,\gamma)^{23}$Na on the chemical ejecta of intermediate-mass stars,
with particular focus on the thermally-pulsing asymptotic giant branch (TP-AGB)
stars that experience hot-bottom burning. To this aim we use the PARSEC and
COLIBRI codes to compute the complete evolution, from the pre-main sequence up
to the termination of the TP-AGB phase, of a set of stellar models with initial
masses in the range $3.0\,M_{\odot} - 6.0\,M_{\odot}$, and metallicities
$Z_{\rm i}=0.0005$, $Z_{\rm i}=0.006$, and $Z_{\rm i} = 0.014$. We find that
the new LUNA measures have much reduced the nuclear uncertainties of the
$^{22}$Ne and $^{23}$Na AGB ejecta, which drop from factors of $\simeq 10$ to
only a factor of few for the lowest metallicity models. Relying on the most
recent estimations for the destruction rate of $^{23}$Na, the uncertainties
that still affect the $^{22}$Ne and $^{23}$Na AGB ejecta are mainly dominated
by evolutionary aspects (efficiency of mass-loss, third dredge-up, convection).
Finally, we discuss how the LUNA results impact on the hypothesis that invokes
massive AGB stars as the main agents of the observed O-Na anti-correlation in
Galactic globular clusters. We derive quantitative indications on the
efficiencies of key physical processes (mass loss, third dredge-up, sodium
destruction) in order to simultaneously reproduce both the Na-rich, O-poor
extreme of the anti-correlation, and the observational constraints on the CNO
abundance. Results for the corresponding chemical ejecta are made publicly
available.


title: Tunable Sensitivity to Large Errors in Neural Network Training

abstract:
  When humans learn a new concept, they might ignore examples that they cannot
make sense of at first, and only later focus on such examples, when they are
more useful for learning. We propose incorporating this idea of tunable
sensitivity for hard examples in neural network learning, using a new
generalization of the cross-entropy gradient step, which can be used in place
of the gradient in any gradient-based training method. The generalized gradient
is parameterized by a value that controls the sensitivity of the training
process to harder training examples. We tested our method on several benchmark
datasets. We propose, and corroborate in our experiments, that the optimal
level of sensitivity to hard example is positively correlated with the depth of
the network. Moreover, the test prediction error obtained by our method is
generally lower than that of the vanilla cross-entropy gradient learner. We
therefore conclude that tunable sensitivity can be helpful for neural network
learning.


title: Instability in Reaction-Superdiffusion Systems

abstract:
  We study the effect of superdiffusion on the instability in
reaction-diffusion systems. It is shown that reaction-superdiffusion systems
close to a Turing instability are equivalent to a time-dependent
Ginzburg-Landau model and the corresponding free energy is introduced. This
generalized free energy which depends on the superdiffusion exponent governs
the stability, dynamics and the fluctuations of reaction-superdiffusion systems
near the Turing bifurcation. In addition, we show that for a general
n-component reaction-superdiffusion system, a fractional complex Ginzburg-
Landau equation emerges as the amplitude equation near a Hopf instability.
Numerical simulations of this equation are carried out to illustrate the effect
of superdiffusion on spatio-temporal patterns. Finally the effect of
superdiffusion on the instability in Brusselator model, as a special case of
reaction-diffusion systems, is studied. In general superdiffusion introduces a
new parameter that changes the behavior of the system near the instability.


title: Timing Matters: Online Dynamics in Broadcast Games

abstract:
  A central question in algorithmic game theory is to measure the inefficiency
(ratio of costs) of Nash equilibria (NE) with respect to socially optimal
solutions. The two established metrics used for this purpose are price of
anarchy (POA) and price of stability (POS), which respectively provide upper
and lower bounds on this ratio. A deficiency of these metrics, however, is that
they are purely existential and shed no light on which of the equilibrium
states are reachable in an actual game, i.e., via natural game dynamics. This
is particularly striking if these metrics differ significantly, such as in
network design games where the exponential gap between the best and worst NE
states originally prompted the notion of POS in game theory (Anshelevich et
al., FOCS 2002). In this paper, we make progress toward bridging this gap by
studying network design games under natural game dynamics.
  First we show that in a completely decentralized setting, where agents
arrive, depart, and make improving moves in an arbitrary order, the
inefficiency of NE attained can be polynomially large. This implies that the
game designer must have some control over the interleaving of these events in
order to force the game to attain efficient NE. We complement our negative
result by showing that if the game designer is allowed to execute a sequence of
improving moves to create an equilibrium state after every batch of agent
arrivals or departures, then the resulting equilibrium states attained by the
game are exponentially more efficient, i.e., the ratio of costs compared to the
optimum is only logarithmic. Overall, our two results establish that in network
games, the efficiency of equilibrium states is dictated by whether agents are
allowed to join or leave the game in arbitrary states, an observation that
might be useful in analyzing the dynamics of other classes of games with
divergent POS and POA bounds.


title: Multi-frequency polarimetry of a complete sample of PACO radio sources

abstract:
  We present high sensitivity polarimetric observations in 6 bands covering the
5.5-38 GHz range of a complete sample of 53 compact extragalactic radio sources
brighter than 200 mJy at 20 GHz. The observations, carried out with the
Australia Telescope Compact Array (ATCA), achieved a 91% detection rate (at 5
sigma). Within this frequency range the spectra of about 95% of sources are
well fitted by double power laws, both in total intensity and in polarisation,
but the spectral shapes are generally different in the two cases. Most sources
were classified as either steep- or peaked-spectrum but less than 50% have the
same classification in total and in polarised intensity. No significant trends
of the polarisation degree with flux density or with frequency were found. The
mean variability index in total intensity of steep-spectrum sources increases
with frequency for a 4-5 year lag, while no significant trend shows up for the
other sources and for the 8 year lag. In polarisation, the variability index,
that could be computed only for the 8 year lag, is substantially higher than in
total intensity and has no significant frequency dependence.


title: First integrals of the axisymmetric shape equation of lipid membranes

abstract:
  The shape equation of lipid membranes [Zhong-can and Helfrich(1987) PRL 59
2486] is a fourth-order partial differential equation. Under the axisymmetric
condition, this equation was transformed into a second-order ordinary
differential equation (ODE) by Zheng and Liu [Zheng and Liu(1993) PRE 48 2856].
Here we try to further reduce this second-order ODE to a first-order ODE by
seeking for first integrals according to the Noether theorem. We indeed find a
first integral when the second-order ODE is invariant under conformation
transformations. We obtain the mechanical interpretation of the first integral
by using the membrane stress tensor.


title: Locally Enhanced and Tunable Optical Chirality in Helical Metamaterials

abstract:
  We report on a numerical study of optical chirality. Intertwined gold helices
illuminated with plane waves concentrate right and left circularly polarized
electromagnetic field energy to sub-wavelength regions. These spots of enhanced
chirality can be smoothly shifted in position and magnitude by varying
illumination parameters, allowing for the control of light-matter interactions
on a nanometer scale.


title: Calculated g-factors of 5d double perovskites Ba2NaOsO6 and Ba2YOsO6

abstract:
  Using Wannier functions to represent the density functional results we
calculate the hybridization corrections to the orbital momentum operator in the
Os 5d shell of Mott insulators Ba2NaOsO6 and Ba2YOsO6. The g-factors are
obtained by evaluating the spin and orbital momentum operators in the atomic
ground states of the Os ion. While the hybridization corrections play minor
role in d3 ion of Ba2YOsO6 with dominant spin moment, they are instrumental for
observation of non- zero g-factor of the d1 ions of Ba2NaOsO6. In addition we
analyze the exchange interactions in Ba2YOsO6 and find them consistent with the
reported magnetic structure.


title:
Negative Kerr nonlinearity of graphene as seen via chirped-pulse-pumped
  self-phase modulation

abstract:
  We experimentally demonstrate a negative Kerr nonlinearity for quasi-undoped
graphene. Hereto, we introduce the method of chirped-pulse-pumped self-phase
modulation and apply it to graphene-covered silicon waveguides at telecom
wavelengths. The extracted Kerr-nonlinear index for graphene equals n2,gr =
-10^(-13) m^2/W. Whereas the sign of n2,gr turns out to be negative in contrast
to what has been assumed so far, its magnitude is in correspondence with that
observed in earlier experiments. Graphene's negative Kerr nonlinearity strongly
impacts how graphene should be exploited for enhancing the nonlinear response
of photonic (integrated) devices exhibiting a positive nonlinearity. It also
opens up the possibility of using graphene to annihilate unwanted nonlinear
effects in such devices, to develop unexplored approaches for establishing Kerr
processes, and to extend the scope of the "periodic poling" method often used
for second-order nonlinearities towards third-order Kerr processes. Because of
the generic nature of the chirped-pulse-pumped self-phase modulation method, it
will allow fully characterizing the Kerr nonlinearity of essentially any novel
(2D) material.


title:
Magnetic fields on young, moderately rotating Sun-like stars II. EK
  Draconis (HD 129333)

abstract:
  The magnetic fields, activity and dynamos of young solar-type stars can be
empirically studied using time-series of spectropolarimetric observations and
tomographic imaging techniques such as Doppler imaging and Zeeman Doppler
imaging. In this paper we use these techniques to study the young Sun-like star
EK Draconis (Sp-Type: G1.5V, HD 129333) using ESPaDOnS at the
Canada-France-Hawaii Telescope and NARVAL at the T\`elescope Bernard Lyot. This
multi-epoch study runs from late 2006 until early 2012. We measure high levels
of chromospheric activity indicating an active, and varying, chromosphere.
Surface brightness features were constructed for all available epochs. The
2006/7 and 2008 data show large spot features appearing at
intermediate-latitudes. However, the 2012 data indicate a distinctive polar
spot. We observe a strong, almost unipolar, azimuthal field during all epochs
that is similar to that observed on other Sun-like stars. Using magnetic
features, we determined an average equatorial rotational velocity, \Omega_eq,
of 2.50 +/- 0.08 rad/d. High levels of surface differential rotation were
measured with an average rotational shear, \Delta\Omega, of 0.27 +0.24-0.26
rad/d. During an intensively observed 3-month period from December 2006 until
February 2007, the magnetic field went from predominantly toroidal ( approx.
80%) to a more balanced poloidal-toroidal (approx. 40-60%) field. Although the
large-scale magnetic field evolved over the epochs of our observations, no
polarity reversals were found in our data.


title: Convergence Analysis of MAP based Blur Kernel Estimation

abstract:
  One popular approach for blind deconvolution is to formulate a maximum a
posteriori (MAP) problem with sparsity priors on the gradients of the latent
image, and then alternatingly estimate the blur kernel and the latent image.
While several successful MAP based methods have been proposed, there has been
much controversy and confusion about their convergence, because sparsity priors
have been shown to prefer blurry images to sharp natural images. In this paper,
we revisit this problem and provide an analysis on the convergence of MAP based
approaches. We first introduce a slight modification to a conventional joint
energy function for blind deconvolution. The reformulated energy function
yields the same alternating estimation process, but more clearly reveals how
blind deconvolution works. We then show the energy function can actually favor
the right solution instead of the no-blur solution under certain conditions,
which explains the success of previous MAP based approaches. The reformulated
energy function and our conditions for the convergence also provide a way to
compare the qualities of different blur kernels, and we demonstrate its
applicability to automatic blur kernel size selection, blur kernel estimation
using light streaks, and defocus estimation.


title: Synthesizing invariants by solving solvable loops

abstract:
  When proving invariance properties of a program, we face two problems. The
first problem is related to the necessity of proving tautologies of considered
assertion language, whereas the second manifests in the need of finding
sufficiently strong invariants. This paper focuses on the second problem and
describes a new method for the automatic generation of loop invariants that
handles polynomial and non deterministic assignments. This technique is based
on the eigenvector generation for a given linear transformation and on the
polynomial optimization problem, which we implemented in the open-source tool
Pilat.


title:
Simultaneous description of bulk and interfacial properties of fluids by
  the Mie potential

abstract:
  The vapor-liquid equilibrium (VLE) of the Mie potential, where the dispersive
exponent is constant (m = 6) while the repulsive exponent n is varied between 9
and 48, is systematically investigated by molecular simulation. For systems
with planar vapor-liquid interfaces, long-range correction expressions are
derived, so that interfacial and bulk properties can be computed accurately.
The present simulation results are found to be consistent with the available
body of literature on the Mie fluid which is substantially extended. On the
basis of correlations for the considered thermodynamic properties, a
multicriteria optimization becomes viable. Thereby, users can adjust the three
parameters of the Mie potential to the properties of real fluids, weighting
different thermodynamic properties according to their importance for a
particular application scenario. In the present work, this is demonstrated for
carbon dioxide for which different competing objective functions are studied
which describe the accuracy of the model for representing the saturated liquid
density, the vapor pressure and the surface tension. It is shown that models
can be found which describe simultaneously the saturated liquid density and
vapor pressure with good accuracy, and it is discussed to what extent this
accuracy can be upheld as the model accuracy for the surface tension is further
improved.

categories: cond-mat.soft cond-mat.stat-mech math.OC physics.chem-ph


title:
Polarized Lambda hyperon production in Semi-inclusive deep inelastic
  scattering off an unpolarized nulceon target

abstract:
  We study the production of polarized $\Lambda$ hyperon in semi-inclusive deep
inelastic scattering off an unpolarized target. We include the cases in which
the $\Lambda$ hyperon is longitudinally polarized or transversely polarized,
and in which the lepton beam is unpolarized or longitudinally polarized. Within
the framework of the transverse momentum dependent factorization, we take into
account the complete decomposition of the parton correlator for fragmentation
up to twist-3. We present the cross section of the process to order $1/Q$. The
expressions of the polarized structure functions, which may give rise to
various spin asymmetries, are also given.


title: The right top coupling in the aligned two-Higgs-doublet model

abstract:
  We compute the right top quark coupling in the aligned two-Higgs-doublet
model. In the Standard Model the real part of this coupling is dominated by
QCD-gluon-exchange diagram, but the imaginary part, instead, is purely
electroweak at one loop. Within this model we show that values for the
imaginary part of the coupling up to one order of magnitude larger than the
electroweak prediction can be obtained. For the real part of the electroweak
contribution we find that it can be up to three orders of magnitude larger than
the standard model one. We also present detailed results of the one loop
analytical computation.


title: New High-Pressure Phases of MoSe$_2$ and MoTe$_2$

abstract:
  Three Mo-based transition metal dichalcogenides MoS$_2$, MoSe$_2$ and
MoTe$_2$ share at ambient conditions the same structure 2H$_c$, consisting of
layers where Mo atoms are surrounded by six chalcogen atoms in trigonal prism
coordination. The knowledge of their high-pressure behaviour is, however,
limited, particularly in case of MoSe$_2$ and MoTe$_2$. The latter materials do
not undergo a layer-sliding transition 2H$_c$ $\rightarrow$ 2H$_a$ known in
MoS$_2$ and currently no other stable phase besides 2H$_c$ is known in these
systems at room temperature. Employing evolutionary crystal structure
prediction in combination with \textit{ab initio} calculations we study the
zero-temperature phase diagram of both materials up to Mbar pressures. We find
a tetragonal phase with space group \textit{P4/mmm}, previously predicted in
MoS$_2$, to become stable in MoSe$_2$ at 118 GPa. In MoTe$_2$ we predict at 50
GPa a transition to a new layered tetragonal structure with space group
\textit{I4/mmm}, similar to CaC$_2$, where Mo atoms are surrounded by eight Te
atoms. The phase is metallic already at the transition pressure and becomes a
good metal beyond 1 Mbar. We discuss chemical trends in the family of Mo-based
transition metal dichalcogenides and suggest that MoTe$_2$ likely offers the
easiest route towards the post-2H phases.


title:
Fuchsian systems for Dotsenko-Fateev multipoint correlation functions
  and similar integrals of hypergeometric type

abstract:
  The Dotsenko-Fateev integral is an analytic function of one complex variable
expressing the amplitude in the 4-point correlator of the 2D conformal field
theory. Dotsenko-Fateev found ODE of third order with Fuchsian singularities
satisfied by their integral. In the present paper, this work is extended to
generalized Dotsenko-Fateev integrals, in particular those associated to
arbitrary multipoint correlators, and Pfaff systems of PDE of Fuchsian type are
constructed for them. The ubiquity of the Fuchsian systems is in that they
permit to obtain local expansions of solutions in the neighborhoods of
singularities of the system.


title: Multi-View 3D Object Detection Network for Autonomous Driving

abstract:
  This paper aims at high-accuracy 3D object detection in autonomous driving
scenario. We propose Multi-View 3D networks (MV3D), a sensory-fusion framework
that takes both LIDAR point cloud and RGB images as input and predicts oriented
3D bounding boxes. We encode the sparse 3D point cloud with a compact
multi-view representation. The network is composed of two subnetworks: one for
3D object proposal generation and another for multi-view feature fusion. The
proposal network generates 3D candidate boxes efficiently from the bird's eye
view representation of 3D point cloud. We design a deep fusion scheme to
combine region-wise features from multiple views and enable interactions
between intermediate layers of different paths. Experiments on the challenging
KITTI benchmark show that our approach outperforms the state-of-the-art by
around 25% and 30% AP on the tasks of 3D localization and 3D detection. In
addition, for 2D detection, our approach obtains 10.3% higher AP than the
state-of-the-art on the hard data among the LIDAR-based methods.


title: Examining A Renormalizable Supersymmetric SO(10) Model

abstract:
  We examine a renormalizable SUSY SO(10) model without fine-tuning. We show
how to construct MSSM doublets and to predict proton decay. We find that in the
minimal set of Yukawa couplings the model is consistent with the experiments,
while including $120_H$ to fit the data there are inconsistencies.


title: Riemannian Rigidity of the Parallel Postulate in Total Curvature

abstract:
  We prove that the Euclidean plane is the only Riemannian plane with total
curvature and free of conjugate points that satisfies Playfair's version of the
parallel postulate.


title: Importance of closed quark loops for lattice QCD studies of tetraquarks

abstract:
  To investigate the light scalar tetraquark candidate $a_0(980)$ (quantum
numbers $J^P =0^+$), a correlation matrix including a variety of two- and
four-quark interpolating operators has to be computed. We discuss efficient
techniques to compute the elements of this correlation matrix, in particular
diagrams with closed quark loops. Furthermore, we present evidence that such
diagrams are not negligible given our precision, and their contribution is
essential to obtain physically meaningful results. In particular, we find
indications of the existence of an "additional" state around the two-particle
thresholds of $K+ \bar K$ and $\eta +\pi$, which could correspond to the
$a_0(980)$ meson.


title:
Modulation of the superconducting critical temperature due to quantum
  confinement at the LaAlO$_3$/SrTiO$_3$ interface

abstract:
  Superconductivity develops in bulk doped SrTiO$_3$ and at the
LaAlO$_3$/SrTiO$_3$ interface with a dome-shaped density dependence of the
critical temperature $T_c$, despite different dimensionalities and geometries.
We propose that the $T_c$ dome of LaAlO$_3$/SrTiO$_3$ is a shape resonance due
to quantum confinement of superconducting bulk SrTiO$_3$. We substantiate this
interpretation by comparing the exact solutions of a three-dimensional and
quasi-two-dimensional two-band BCS gap equation. This comparison highlights the
role of heavy bands for $T_c$ in both geometries. For bulk SrTiO$_3$, we
extract the density dependence of the pairing interaction from the fit to
experimental data. We apply quantum confinement in a square potential well of
finite depth and calculate $T_c$ in the confined configuration. We compare the
calculated $T_c$ to transport experiments and provide an explanation as to why
the optimal $T_c$'s are so close to each other in two-dimensional interfaces
and the three-dimensional bulk material.


title: Weakly distance-regular digraphs of valency three, II

abstract:
  In this paper, we classify commutative weakly distance-regular digraphs of
valency 3 with girth more than 2 and one type of arcs. Combining [8, Theorem
1.2], [10, Theorem 1.3] and [11, Theorem 1], commutative weakly distanceregular
digraphs of valency 3 are completely determined.


title: A simple technique for the automation of bubble size measurements

abstract:
  An increasing number of research topics and applications ask for a precise
measurement of the size distribution of small bubbles in a liquid - and hence
for reliable and automated image analysis. However, due to the strong mismatch
between the refractive index of a liquid and a gas, bubbles deform strongly the
path of light rays, rendering automated bubble size analysis a challenging
task. We show here how this challenge can be met using the fact that bubbles
act like inverted, spherical lenses with a curvature which is the inverse of
the bubble radius. The imaging properties of each bubble can then be used to
accurately determine the radius of the bubble upon imaging an object which can
be filtered easily by a computer. When bubbles are large enough to be deformed
under the influence of gravity, it is more appropriate to measure their size
after squeezing them between two narrowly spaced glass plates. We therefore
show here, how the analysis can be extended to this case; and how both
approaches can be combined to measure the size distributions of strongly
polydisperse foams containing simultaneously small (several 10s of micrometres)
and large bubbles (several 100s of micrometres).


title:
Experimental realization of a Dirac monopole through the decay of an
  isolated monopole

abstract:
  We experimentally observe the decay dynamics of deterministically created
isolated monopoles in spin-1 Bose-Einstein condensates. As the condensate
undergoes a change between magnetic phases, the isolated monopole gradually
evolves into a spin configuration hosting a Dirac monopole in its synthetic
magnetic field. We characterize in detail the Dirac monopole by measuring the
particle densities of the spin states projected along different quantization
axes. Importantly, we observe the spontaneous emergence of nodal lines in the
condensate density that accompany the Dirac monopole. We also demonstrate that
the monopole decay accelerates in weaker magnetic field gradients.


title: Multiframe Motion Coupling for Video Super Resolution

abstract:
  The idea of video super resolution is to use different view points of a
single scene to enhance the overall resolution and quality. Classical energy
minimization approaches first establish a correspondence of the current frame
to all its neighbors in some radius and then use this temporal information for
enhancement. In this paper, we propose the first variational super resolution
approach that computes several super resolved frames in one batch optimization
procedure by incorporating motion information between the high-resolution image
frames themselves. As a consequence, the number of motion estimation problems
grows linearly in the number of frames, opposed to a quadratic growth of
classical methods and temporal consistency is enforced naturally. We use
infimal convolution regularization as well as an automatic parameter balancing
scheme to automatically determine the reliability of the motion information and
reweight the regularization locally. We demonstrate that our approach yields
state-of-the-art results and even is competitive with machine learning
approaches.


title:
Complex biphase nature of the superconducting dome of the FeSe phase
  diagram

abstract:
  Single crystal synchrotron X-ray diffraction as a function of temperature and
pressure has revealed a complex biphase mixture in superconducting FeSe. Based
on our experimental results we construct a phase diagram where structural
behavior and superconducting properties of FeSe are found to be correlated. We
show that below 6 GPa, where pressure promotes the superconducting critical
temperature, the FeSe structure is composed of 2D layers of edge-shared FeSe4
tetrahedra, while above 6 GPa the superconductivity is strongly suppressed on
formation of a new orthorhombic polymorph characterized by a 3D network of face
sharing FeSe6 octahedra. Therefore changes in topology and connectivity of the
FeSe structure are found to be detrimental for superconductivity to exist. This
previously controversial crystal structure of the high pressure polymorph of
FeSe was also unambiguously determined. High pressure FeSe adopts an
orthorhombic MnP-type structure (Pnma) which corresponds to a slightly
distorted hexagonal NiAs-type arrangement (P63/mmc). The structural
transformation from the low- to high-pressure FeSe polymorph is first order in
nature and is manifested as antiparallel displacements within the Fe and Se
sublattices.


title: The many facets of community detection in complex networks

abstract:
  Community detection, the decomposition of a graph into essential building
blocks, has been a core research topic in network science over the past years.
Since a precise notion of what constitutes a community has remained evasive,
community detection algorithms have often been compared on benchmark graphs
with a particular form of assortative community structure and classified based
on the mathematical techniques they employ. However, this comparison can be
misleading because apparent similarities in their mathematical machinery can
disguise different goals and reasons for why we want to employ community
detection in the first place. Here we provide a focused review of these
different motivations that underpin community detection. This problem-driven
classification is useful in applied network science, where it is important to
select an appropriate algorithm for the given purpose. Moreover, highlighting
the different facets of community detection also delineates the many lines of
research and points out open directions and avenues for future research.


title: Neutrino-Nucleus Cross Sections for Oscillation Experiments

abstract:
  Neutrino oscillations physics is entered in the precision era. In this
context accelerator-based neutrino experiments need a reduction of systematic
errors to the level of a few percent. Today one of the most important sources
of systematic errors are neutrino-nucleus cross sections which in the
hundreds-MeV to few-GeV energy region are known with a precision not exceeding
20%. In this article we review the present experimental and theoretical
knowledge of the neutrino-nucleus interaction physics. After introducing
neutrino oscillation physics and accelerator-based neutrino experiments, we
overview general aspects of the neutrino-nucleus cross sections, both
theoretical and experimental views. Then we focus on these quantities in
different reaction channels. We start with the quasielastic and
quasielastic-like cross section, putting a special emphasis on multinucleon
emission channel which attracted a lot of attention in the last few years. We
review the main aspects of the different microscopic models for this channel by
discussing analogies and differences among them.The discussion is always driven
by a comparison with the experimental data. We then consider the one pion
production channel where data-theory agreement remains very unsatisfactory. We
describe how to interpret pion data, then we analyze in particular the puzzle
related to the impossibility of theoretical models and Monte Carlo to
simultaneously describe MiniBooNE and MINERvA experimental results. Inclusive
cross sections are also discussed, as well as the comparison between the
$\nu_\mu$ and $\nu_e$ cross sections, relevant for the CP violation
experiments. The impact of the nuclear effects on the reconstruction of
neutrino energy and on the determination of the neutrino oscillation parameters
is reviewed. A window to the future is finally opened by discussing projects
and efforts in future detectors, beams, and analysis.


title: Autoequivalences of the category of schemes

abstract:
  We prove that there is no non-trivial aoutoequvivalence of the categoryof
schemes of finite type over $\mathbb{Q}$.


title:
Stable freestanding thin films of copolymer melts far from the glass
  transition

abstract:
  Thin polymer films have attracted attention because of both their broad range
of applications and of the fundamental questions they raise regarding the
dynamic response of confined polymers. These films are unstable if the
temperature is above their glass transition temperature Tg. Here, we describe
freestanding thin films of centimetric dimensions made of a comb copolymer melt
far from its glass transition that are stable for more than a day. These long
lifetimes allowed us to characterize the drainage dynamics and the thickness
profile of the films. Stratified regions appear as the film drains. We have
evidence that the stability, thinning dynamics and thickness profile of the
films result from structural forces in the melt. Understanding the key
mechanisms behind our observations may lead to new developments in polymeric
thin films, foams and emulsions without the use of stabilizing agents.


title:
Detection of confined current paths on oxide surfaces by
  local-conductivity atomic force microscopy with atomic resolution

abstract:
  The analysis of the electronic surface properties of transition metal oxides
being key materials for future nanoelectronics requires a direct
characterization of the conductivity with highest spatial resolution. Using
local conductivity atomic force microscopy (LC-AFM) we demonstrate the
possibility of recording current maps with true atomic resolution. The
application of this technique on surfaces of reduced TiO$_2$ and SrTiO$_3$
reveals that the distribution of surface conductivity has a significant
localized nature. Assisted by density functional theory (DFT) we propose that
the presence of oxygen vacancies in the surface layer of such materials can
introduce short range disturbances of electronic structure with confinement of
metallic states on the nanoscale.


title: Robust regression for mixed Poisson-Gaussian model

abstract:
  This paper focuses on efficient computational approaches to compute
approximate solutions of a linear inverse problem that is contaminated with
mixed Poisson--Gaussian noise, and when there are additional outliers in the
measured data. The Poisson--Gaussian noise leads to a weighted minimization
problem, with solution-dependent weights. To address outliers, the standard
least squares fit-to-data metric is replaced by the Talwar robust regression
function. Convexity, regularization parameter selection schemes, and
incorporation of non-negative constraints are investigated. A projected Newton
algorithm is used to solve the resulting constrained optimization problem, and
a preconditioner is proposed to accelerate conjugate gradient Hessian solves.
Numerical experiments on problems from image deblurring illustrate the
effectiveness of the methods.


title: Superdense Coding with Uniformly Accelerated Particle

abstract:
  We study superdense coding with uniformly accelerated particle in single mode
approximation and beyond single mode approximation. We use four different
functions, the capacity of superdense coding, negativity, discord and the
probability of success for evaluating the final results. In single mode
approximation, all the four functions behave as expected, however in beyond
single mode approximation, except the probability of success, the other three
functions represent peculiar behaviors at least for special ranges where the
beyond single mode approximation is strong.


title:
Specificity-determining DNA triplet code for positioning of human
  pre-initiation complex

abstract:
  The notion that transcription factors bind DNA only through specific,
consensus binding sites has been recently questioned. In a pioneering study by
Pugh and Venters no specific consensus motif for the positioning of the human
pre-initiation complex (PIC) has been identified. Here, we reveal that
nonconsensus, statistical, DNA triplet code provides specificity for the
positioning of the human PIC. In particular, we reveal a highly non-random,
statistical pattern of repetitive nucleotide triplets that correlates with the
genome-wide binding preferences of PIC measured by Chip-exo. We analyze the
triplet enrichment and depletion near the transcription start site (TSS) and
identify triplets that have the strongest effect on PIC-DNA nonconsensus
binding. Our results constitute a proof-of-concept for a new design principle
for protein-DNA recognition in the human genome, which can lead to a better
mechanistic understanding of transcriptional regulation.


title:
Affine matrix rank minimization problem via non-convex fraction function
  penalty

abstract:
  Affine matrix rank minimization problem is a fundamental problem with a lot
of important applications in many fields. It is well known that this problem is
combinatorial and NP-hard in general. In this paper, a continuous promoting low
rank non-convex fraction function is studied to replace the rank function in
this NP-hard problem. Inspired by our former work in compressed sensing, an
iterative singular value thresholding algorithm is proposed to solve the
regularization transformed affine matrix rank minimization problem. For
different $a>0$, we could get a much better result by adjusting the different
value of $a$, which is one of the advantages for the iterative singular value
thresholding algorithm compared with some state-of-art methods. Some
convergence results are established and numerical experiments show that this
thresholding algorithm is feasible for solving the regularization transformed
affine matrix rank minimization problem. Moreover, we proved that the value of
the regularization parameter $\lambda>0$ can not be chosen too large. Indeed,
there exists $\bar{\lambda}>0$ such that the optimal solution of the
regularization transformed affine matrix rank minimization problem is equal to
zero for any $\lambda>\bar{\lambda}$. Numerical experiments on matrix
completion problems show that our method performs powerful in finding a
low-rank matrix and the numerical experiments about image inpainting problems
show that our algorithm has better performances than some state-of-art methods.


title: Electric dipole moment of the neutron from a flavor changing Higgs boson

abstract:
  I consider neutron electric dipole moment contributions induced by flavor
changing Standard Model Higgs boson couplings to quarks. Such couplings might
stem from non-renormalizable $SU(2)_L \times U(1)_Y$ invariant Lagrange terms
of dimension six, containing a product of three Higgs doublets. Previously one
loop diagrams with such couplings were considered in order to constrain {\it
quadratric} expressions of Higgs flavor changing couplings to quarks. In the
present paper the analysis is extended to the two loop level, where there are
diagrams for electric dipole moments of quarks with a flavor changing Higgs
coupling to {\it first order only}. The divergent loops, due to
non-renormalisabillity, are parametrized in terms of an ultraviolet cut-off
$\Lambda$. I also consider QCD corrections, including the mixing with the color
electric dipole moment, while the contribution from the Weinberg operator is
found to be negligible. The effect of QCD corrections is to suppress the bare
result. Using the current experimental bound on the neutron electric dipole
moment, then for cut offs from one to seven TeV, I find a constraint of order
$10^{-3}$ for the imaginary part of the {\it product} of the Higgs flavor
changing coupling for $(d \rightarrow b)$-transition {\it and} the CKM element
$V_{td}$. Assuming that the previous bound of the {\it absolute value} of the
Higgs flavor changing coupling for $(d \rightarrow b)$-transition obtained from
$B_d - \bar{B_d}$-mixing is saturated, the experimental bound on the neutron
electric dipole moment would be reached for the {\it bare} result, {\it if} the
cut off were extended up to about ca 20 TeV. However, QCD corrections suppress
this result by a factor of order ten, and keep the nEDM below the experimental
bound.


title:
Quantum repeaters based on trapped ions with decoherence free subspace
  encoding

abstract:
  Quantum repeaters provide an efficient solution to distribute Bell pairs over
arbitrarily long distances. While scalable architectures are demanding
regarding the number of qubits that need to be controlled, here we present a
quantum repeater scheme aiming to extend the range of present day quantum
communications that could be implemented in the near future with trapped ions
in cavities. We focus on an architecture where ion-photon entangled states are
created locally and subsequently processed with linear optics to create
elementary links of ion-ion entangled states. These links are then used to
distribute entangled pairs over long distances using successive entanglement
swapping operations performed deterministically using ion-ion gates. We show
how this architecture can be implemented while encoding the qubits in a
decoherence free subspace to protect them against collective dephasing. This
results in a protocol that can be used to violate a Bell inequality over
distances of about 800 km assuming state of the art parameters. We discuss how
this could be improved to several thousand kilometers in future setups.


title: Around Jensen's inequality for strongly convex functions

abstract:
  In this paper we use basic properties of strongly convex functions to obtain
new inequalities including Jensen's type and Jensen-Mercer type inequalities.
Applications for special means are pointed out as well. We also give a Jensen's
operator inequality for strongly convex functions. As a corollary, we improve
H\"older-McCarthy inequality under suitable conditions. More precisely we show
that if $Sp\left( A \right)\subset I\subseteq \left( 1,\infty \right)$, then
\[{{\left\langle Ax,x \right\rangle }^{r}}\le \left\langle {{A}^{r}}x,x
\right\rangle -\frac{{{r}^{2}}-r}{2}\left( \left\langle {{A}^{2}}x,x
\right\rangle -{{\left\langle Ax,x \right\rangle }^{2}} \right),\quad r\ge 2\]
and if $Sp\left( A \right)\subset I\subseteq \left( 0,1 \right)$, then
\[\left\langle {{A}^{r}}x,x \right\rangle \le {{\left\langle Ax,x \right\rangle
}^{r}}+\frac{r-{{r}^{2}}}{2}\left( {{\left\langle Ax,x \right\rangle
}^{2}}-\left\langle {{A}^{2}}x,x \right\rangle \right),\quad 0<r<1\] for each
positive operator $A$ and $x\in \mathcal{H}$ with $\left\| x \right\|=1$.


title:
Adaptive Down-Sampling and Dimension Reduction in Time Elastic Kernel
  Machines for Efficient Recognition of Isolated Gestures

abstract:
  In the scope of gestural action recognition, the size of the feature vector
representing movements is in general quite large especially when full body
movements are considered. Furthermore, this feature vector evolves during the
movement performance so that a complete movement is fully represented by a
matrix M of size DxT , whose element M i, j represents the value of feature i
at timestamps j. Many studies have addressed dimensionality reduction
considering only the size of the feature vector lying in R D to reduce both the
variability of gestural sequences expressed in the reduced space, and the
computational complexity of their processing. In return, very few of these
methods have explicitly addressed the dimensionality reduction along the time
axis. Yet this is a major issue when considering the use of elastic distances
which are characterized by a quadratic complexity along the time axis. We
present in this paper an evaluation of straightforward approaches aiming at
reducing the dimensionality of the matrix M for each movement, leading to
consider both the dimensionality reduction of the feature vector as well as its
reduction along the time axis. The dimensionality reduction of the feature
vector is achieved by selecting remarkable joints in the skeleton performing
the movement, basically the extremities of the articulatory chains composing
the skeleton. The temporal dimen-sionality reduction is achieved using either a
regular or adaptive down-sampling that seeks to minimize the reconstruction
error of the movements. Elastic and Euclidean kernels are then compared through
support vector machine learning. Two data sets 1 that are widely referenced in
the domain of human gesture recognition, and quite distinctive in terms of
quality of motion capture, are used for the experimental assessment of the
proposed approaches. On these data sets we experimentally show that it is
feasible, and possibly desirable, to significantly reduce simultaneously the
size of the feature vector and the number of skeleton frames to represent body
movements while maintaining a very good recognition rate. The method proves to
give satisfactory results at a level currently reached by state-of-the-art
methods on these data sets. We experimentally show that the computational
complexity reduction that is obtained makes this approach eligible for
real-time applications.


title:
What is LTE actually used for? An answer through multi-operator,
  crowd-sourced measurement

abstract:
  LTE networks are commonplace nowadays; however, comparatively little is known
about where (and why) they are deployed, and the demand they serve. We shed
some light on these issues through large-scale, crowd-sourced measurement. Our
data, collected by users of the WeFi app, spans multiple operators and multiple
cities, allowing us to observe a wide variety of deployment patterns.
Surprisingly, we find that LTE is frequently used to improve the {\em coverage}
of network rather than the capacity thereof, and that no evidence shows that
video traffic be a primary driver for its deployment. Our insights suggest that
such factors as pre-existing networks and commercial policies have a deeper
impact on deployment decisions than purely technical considerations.


title:
Higher-order vector discrete rogue-wave states in the coupled
  Ablowitz-Ladik equations: exact solutions and stability

abstract:
  An integrable system of two-component nonlinear Ablowitz-Ladik (AL) equations
is used to construct complex rogue-wave (RW) solutions in an explicit form.
First, the modulational instability of continuous waves is studied in the
system. Then, new higher-order discrete two-component RW solutions of the
system are found by means of a newly derived discrete version of a generalized
Darboux transformation. Finally, perturbed evolution of these RW states is
explored in terms of systematic simulations, which demonstrates that tightly
and loosely bound RWs are, respectively, nearly stable and strongly unstable
solutions.


title: Searches for Axionlike Particles Using Gamma-Ray Observations

abstract:
  Axionlike particles (ALPs) are a common prediction of theories beyond the
Standard Model of particle physics that could explain the entirety of the cold
dark matter. These particles could be detected through their mixing with
photons in external electromagnetic fields. Here, we provide a short review
over ALP searches that utilize astrophysical $\gamma$-ray observations. We
summarize current bounds as well as future sensitivities and discuss the
possibility that ALPs alter the $\gamma$-ray opacity of the Universe.


title:
Nano scale thermo-electrical detection of magnetic domain wall
  propagation

abstract:
  In magnetic nanowires with perpendicular magnetic anisotropy (PMA) magnetic
domain walls (DW) are narrow and can move rapidly driven by current induced
torques. This enables important applications like high-density memories for
which the precise detection of the position and motion of a propagating DW is
of utmost interest. Today's DW detection tools are often limited in resolution,
or acquisition speed, or can only be applied on specific materials. Here, we
show that the anomalous Nernst effect provides a simple and powerful tool to
precisely track the position and motion of a single DW propagating in a PMA
nanowire. We detect field and current driven DW propagation in both metallic
heterostructures and dilute magnetic semiconductors over a broad temperature
range. The demonstrated spatial resolution below 20 nm is comparable to the DW
width in typical metallic PMA systems.


title:
A Faster Algorithm for Cuckoo Insertion and Bipartite Matching in Large
  Graphs

abstract:
  Hash tables are ubiquitous in computer science for efficient access to large
datasets. However, there is always a need for approaches that offer compact
memory utilisation without substantial degradation of lookup performance.
Cuckoo hashing is an efficient technique of creating hash tables with high
space utilisation and offer a guaranteed constant access time. We are given $n$
locations and $m$ items. Each item has to be placed in one of the $k\ge2$
locations chosen by $k$ random hash functions. By allowing more than one choice
for a single item, cuckoo hashing resembles multiple choice allocations
schemes. In addition it supports dynamically changing the location of an item
among its possible locations. We propose and analyse an insertion algorithm for
cuckoo hashing that runs in \emph{linear time} with high probability and in
expectation. Previous work on total allocation time has analysed breadth first
search, and it was shown to be linear only in \emph{expectation}. Our algorithm
finds an assignment (with probability 1) whenever it exists. In contrast, the
other known insertion method, known as \emph{random walk insertion}, may run
indefinitely even for a solvable instance. We also present experimental results
comparing the performance of our algorithm with the random walk method, also
for the case when each location can hold more than one item.
  As a corollary we obtain a linear time algorithm (with high probability and
in expectation) for finding perfect matchings in a special class of sparse
random bipartite graphs. We support this by performing experiments on a real
world large dataset for finding maximum matchings in general large bipartite
graphs. We report an order of magnitude improvement in the running time as
compared to the \emph{Hopkraft-Karp} matching algorithm.


title: DSSSD based Spectrometer of the Dubna Gas-Filled Recoil Separator

abstract:
  Recently, in the DGFRS related experiments the discoveries of new superheavy
elements 114 to 118 were successfully performed. As concerns to a background
radical suppression in those experiments it was namely Active correlations
method which was applied to this goal. Note, that application of DSSSD detector
allows one to apply this method more effectively, although with some
difficulties due to neighbor strips edge effects. Present version of the DGFRS
spectrometer is presented. Shapes of ER registered energy spectra in the nat
Yb+48Ca reaction are presented. First results of its application in the
240Pu+48Ca=Fl complete fusion nuclear reaction are presented too. Conclusion,
that edge effects are to a first approximation explained by the role of inter
strips area is drawn.


title:
Universal proximity effect in target search kinetics in the
  few-encounter limit

abstract:
  When does a diffusing particle reach its target for the first time? This
first-passage time (FPT) problem is central to the kinetics of molecular
reactions in chemistry and molecular biology. Here we explain the behavior of
smooth FPT densities, for which all moments are finite, and demonstrate
universal yet generally non-Poissonian long-time asymptotics for a broad
variety of transport processes. While Poisson-like asymptotics arise
generically in the presence of an effective repulsion in the immediate vicinity
of the target, a time-scale separation between direct and reflected indirect
trajectories gives rise to a universal proximity effect: Direct paths, heading
more or less straight from the point of release to the target, become typical
and focused, with a narrow spread of the corresponding first passage times.
Conversely, statistically dominant indirect paths exploring the system size
tend to be massively dissimilar. The initial distance to the target
particularly impacts gene regulatory or competitive stochastic processes, for
which often few binding events determine the regulatory outcome. The proximity
effect is independent of details of the transport, highlighting the robust
character of the FPT features uncovered here.


title: Dyons and Roberge - Weiss transition in lattice QCD

abstract:
  We study lattice QCD with $N_f=2$ Wilson fermions at nonzero imaginary
chemical potential and nonzero temperature. We relate the Roberge - Weiss phase
transition to the properties of dyons which are constituents of the KvBLL
calorons. We present numerical evidence that the characteristic features of the
spectral gap of the overlap Dirac operator as function of an angle modifying
the boundary condition are determined by the $Z_3$ sector of the respective
imaginary chemical potential. We then demonstrate that dyon excitations in
thermal configurations could be responsible (in line with perturbative
excitations) for these phenomena.


title: Performance Limits of Network Densification

abstract:
  Network densification is a promising cellular deployment technique that
leverages spatial reuse to enhance coverage and throughput. Recent work has
identified that at some point ultra-densification will no longer be able to
deliver significant throughput gains. In this paper, we provide a unified
treatment of the performance limits of network densification. We develop a
general framework, which incorporates multi-slope pathloss and the entire space
of shadowing and small scale fading distributions, under strongest cell
association in a Poisson field of interferers. First, our results show that
there are three scaling regimes for the downlink
signal-to-interference-plus-noise ratio (SINR), coverage probability, and
average per-user rate. Specifically, depending on the near-field pathloss and
the fading distribution, the user performance of 5G ultra dense networks (UDNs)
would either monotonically increase, saturate, or decay with increasing network
density. Second, we show that network performance in terms of coverage density
and area spectral efficiency can scale with the network density better than the
user performance does. Furthermore, we provide ordering results for both
coverage and average rate as a means to qualitatively compare different
transmission techniques that may exhibit the same performance scaling. Our
results, which are verified by simulations, provide succinct insights and
valuable design guidelines for the deployment of 5G UDNs.


title: Object Detection using Image Processing

abstract:
  An Unmanned Ariel vehicle (UAV) has greater importance in the army for border
security. The main objective of this article is to develop an OpenCV-Python
code using Haar Cascade algorithm for object and face detection. Currently,
UAVs are used for detecting and attacking the infiltrated ground targets. The
main drawback for this type of UAVs is that sometimes the object are not
properly detected, which thereby causes the object to hit the UAV. This project
aims to avoid such unwanted collisions and damages of UAV. UAV is also used for
surveillance that uses Voila-jones algorithm to detect and track humans. This
algorithm uses cascade object detector function and vision. train function to
train the algorithm. The main advantage of this code is the reduced processing
time. The Python code was tested with the help of available database of video
and image, the output was verified.


title:
On the number of three-term arithmetic progressions in a dense subset of
  $F_q^n$

abstract:
  Let $q$ be an odd prime power. Combining the discussion of Varnavides and a
recent theorem of Ellenberg and Gijswijt, we show that a subset
$A\subset{\mathbb F}_q^n$ will contain many non-trivial three-term arithmetic
progressions, whenever $|A|\geq (c_q q)^n$ for some constant $c_q>0$. After the
first version of our manuscript was uploaded in the arXiv, we learned from
Professors Jacob Fox and Terence Tao that our result is a special case of a
result of Fox and Lovasz [1, Theorem 3]. In fact, [1, Theorem 3] gives a much
better bound than ours. For example, when $q=3$, the lower bound given by Fox
and Lovasz is $|A|^{2}\cdot (|A|q^{-n})^{11.901}$, while our bound is
$|A|^{2}\cdot (|A|q^{-n})^{25.803}$. We thank Professors Jacob Fox and Terence
Tao for their helpful comments on our manuscript. [1] Jacob Fox, L\'aszl\'o
Mikl\'os Lov\'asz, A tight bound for Green's arithmetic triangle removal lemma
in vector spaces, preprint, arXiv:1606.01230.


title: Patterns in treeshelves

abstract:
  We study the distribution and the popularity of left children on sets of
treeshelves avoiding a pattern of size three. (Treeshelves are ordered binary
increasing trees where every child is connected to its parent by a left or a
right link.) The considered patterns are sub-treeshelves, and for each such a
pattern we provide exponential generating function for the corresponding
distribution and popularity. Finally, we present constructive bijections
between treeshelves avoiding a pattern of size three and some classes of
simpler combinatorial objects.


title: X-ray variability of cool stars: Magnetic activity and accretion

abstract:
  This article provides a review of X-ray variability from late-type stars with
particular focus on the achievements of XMM-Newton and its potential for future
studies in this field.


title:
Nonlocal general vector nonlinear Schroedinger equations:Integrability,
  PT symmetribility, and solutions

abstract:
  A family of new one-parameter (\epsilon_x=\pm 1) nonlinear wave models
(called G_{\epsilon_x}^{(nm)} model) is presented, including both the local
(\epsilon_x=1) and new integrable nonlocal $(\epsilon_x=-1)$ general vector
nonlinear Schr\"odinger (VNLS) equations with the self-phase, cross-phase, and
multi-wave mixing modulations. The nonlocal G_{-1}^{(nm)} model is shown to
possess the Lax pair and infinite number of conservation laws for $m=1$. We
also establish a connection between the G_{\epsilon_x}^{(nm)} model and some
known models. Some symmetric reductions and exact solutions (e.g., bright,
dark, and mixed bright-dark solitons) of the representative nonlocal systems
are also found. Moreover, we find that the new general two-parameter
(\epsilon_x, \epsilon_t) model (called G_{\epsilon_x, \epsilon_t}^{(nm)} model)
including the G_{\epsilon_x}^{(nm)} model is invariant under the PT-symmetric
transformation and the PT symmetribility of its self-induced potentials is
discussed for the distinct two parameters (\epsilon_x, \epsilon_t)=(\pm 1, \pm
1).


title: A Symbolic Method for the Analysis of a Nonlinear Two-Mass-Skate Model

abstract:
  Multibody systems usually give rise to complex nonlinear dynamics, and the
bicycle is not an exception. Even a simple model as the Two-Mass-Skate presents
a long expression of the kinetic energy, making difficult to write explicitly
the equations of motion. Instead of linearising or approximating the model, we
will overcome this issue by using a functional expression of the kinetic
energy. With introduction of appropriate nonlinear functions, the equations of
motion are written in a form that can be easily handled despite their
complexity. A stability analysis of the dynamics is then conducted.


title: Local fractality: the case of forest fires in Portugal

abstract:
  The research deals with a study of local fractality in spatial distribution
of forest fires in Portugal using the sandbox method. The general procedure is
the following: (a) define a circle centred in each and all events with
increasing radius R; (b) count the number of other events located within the
circle of radius R, N(R); (c) plot the growth curve which is the functional
dependence of N(R) versus R; and (d) estimate the local fractal dimension as
the slope on log[N(R)] versus log[R]. The computation is carried out by using
the location of every fire event as a centre but without the final averaging
over all the fires for a given R, which is usually performed to get a global
fractal dimension and to estimate global clustering. Sandbox method is widely
used in many applications in physics and other subjects. The local procedure
has the ability to provide the most complete information regarding the spatial
distribution of clustering and avoiding non-homogeneity and non-stationarity
problems. Most of the analysis was performed using the National Mapping Burnt
Area (NMBA) database which accounts for 32,156 fires during the 1975 - 2013
period. The results of local analysis are compared with a randomly generated
pattern in forest zones (validity domain). The results demonstrate interesting
local spatial patterns of clustering. Some results on global measures are
reported as well.


title: Local optimality of cubic lattices for interaction energies

abstract:
  We study the local optimality of Simple Cubic, Body-Centred-Cubic and
Face-Centred-Cubic lattices among Bravais lattices of fixed density for some
finite energy per point. Following the work of Ennola [Math. Proc. Cambridge,
60:855--875, 1964], we prove that these lattices are critical points of all the
energies, we write the second derivatives in a simple way and we investigate
the local optimality of these lattices for the theta function and the
Lennard-Jones-type energies. In particular, we prove the local minimality of
the FCC lattice (resp. BCC lattice) for large enough (resp. small enough)
values of its scaling parameter and we also prove the fact that the simple
cubic lattice is a saddle point of the energy. Furthermore, we prove the local
minimality of the FCC and the BCC lattices at high density (with an optimal
explicit bound) and its local maximality at low density in the
Lennard-Jones-type potential case. We then show the local minimality of FCC and
BCC lattices among all the Bravais lattices (without a density constraint). The
largest possible open interval of density's values where the Simple Cubic
lattice is a local minimizer is also computed.


title:
Electron and phonon spectra dynamics and features of phase transitions
  in sodium at P=0-100 GPa

abstract:
  Electron and phonon spectra dynamics, as well as features of structural
transitions and melting of sodium under pressure within range 0 to 100 GPa are
investigated. Electron and phonon spectra of crystal sodium are calculated ab
initio within the density functional theory by means of the LMTART-7 software
package (Savrasov-Savrasov: 1992; Savrasov: 1996; Savrasov: 2004), allowing the
fully potential method of linear muffin-tin orbitals. Using the Lindemann
measure and the calculated phonon spectra the theoretical values of melting
points corresponding to the experimental data (Gregoryanz, et al: 2005;
Gregoryanz, et al: 2008) are obtained. Features of electron and phonon spectra
dynamics in the melting curve maximum vicinity and within cI2->cI4 structural
transition range are discussed.


title: Infinite Variational Autoencoder for Semi-Supervised Learning

abstract:
  This paper presents an infinite variational autoencoder (VAE) whose capacity
adapts to suit the input data. This is achieved using a mixture model where the
mixing coefficients are modeled by a Dirichlet process, allowing us to
integrate over the coefficients when performing inference. Critically, this
then allows us to automatically vary the number of autoencoders in the mixture
based on the data. Experiments show the flexibility of our method, particularly
for semi-supervised learning, where only a small number of training samples are
available.


title:
NMRProcFlow: A graphical and interactive tool dedicated to 1D spectra
  processing for NMR-based metabolomics

abstract:
  Concerning NMR-based metabolomics, 1D spectra processing often requires an
expert eye for disentangling the intertwined peaks, and so far the best way is
to proceed interactively with a spectra viewer. NMRProcFlow is a graphical and
interactive 1D NMR (1H \& 13C) spectra processing tool dedicated to metabolic
fingerprinting and targeted metabolomic, covering all spectra processing steps
including baseline correction, chemical shift calibration, alignment. It does
not require programming skills. Biologists and NMR spectroscopists can easily
interact and develop synergies by visualizing the NMR spectra along with their
corresponding experimental-factor levels, thus setting a bridge between
experimental design and subsequent statistical analyses.


title:
Gravitational mechanism for baryogenesis in the cosmological QCD phase
  transition

abstract:
  One of the biggest puzzles in modern cosmology is the observed baryon
asymmetry in the universe. In current models of baryogenesis gravity plays a
secondary role, although the process is believed to have happened in the early
universe, under the influence of an intense gravitational field. In the present
work we resume Sakharov's original program for baryogenesis and propose a
central role for gravity in the process. This is achieved through a non-minimal
coupling (NMC) between the gravitational field and both the strong interaction
field and the quark fields. When in action, the present mechanism leads to
baryon number non-conservation and CP violation. Moreover, the NMC induces
reduced effective quark masses, which favours a first order QCD phase
transition. As a consequence, a baryon asymmetry can be attained in the
transition from the quark epoch to the hadron epoch.


title: Interpolation-Based GR(1) Assumptions Refinement

abstract:
  This paper considers the problem of assumptions refinement in the context of
unrealizable specifications for reactive systems. We propose a new
counterstrategy-guided synthesis approach for GR(1) specifications based on
Craig's interpolants. Our interpolation-based method identifies causes for
unrealizability and computes assumptions that directly target unrealizable
cores, without the need for user input. Thereby, we discuss how this property
reduces the maximum number of steps needed to converge to realizability
compared with other techniques. We describe properties of interpolants that
yield helpful GR(1) assumptions and prove the soundness of the results.
Finally, we demonstrate that our approach yields weaker assumptions than
baseline techniques, and finds solutions in case studies that are unsolvable
via existing techniques.


title:
ATR4S: Toolkit with State-of-the-art Automatic Terms Recognition Methods
  in Scala

abstract:
  Automatically recognized terminology is widely used for various
domain-specific texts processing tasks, such as machine translation,
information retrieval or sentiment analysis. However, there is still no
agreement on which methods are best suited for particular settings and,
moreover, there is no reliable comparison of already developed methods. We
believe that one of the main reasons is the lack of state-of-the-art methods
implementations, which are usually non-trivial to recreate. In order to address
these issues, we present ATR4S, an open-source software written in Scala that
comprises more than 15 methods for automatic terminology recognition (ATR) and
implements the whole pipeline from text document preprocessing, to term
candidates collection, term candidates scoring, and finally, term candidates
ranking. It is highly scalable, modular and configurable tool with support of
automatic caching. We also compare 10 state-of-the-art methods on 7 open
datasets by average precision and processing time. Experimental comparison
reveals that no single method demonstrates best average precision for all
datasets and that other available tools for ATR do not contain the best
methods.


title:
Evidence for the two-body charmless baryonic decay $B^+ \to p
  \bar\Lambda$

abstract:
  A search for the rare two-body charmless baryonic decay $B^+ \to p
\bar\Lambda$ is performed with $pp$ collision data, corresponding to an
integrated luminosity of $3\,\mbox{fb}^{-1}$, collected by the LHCb experiment
at centre-of-mass energies of 7 and 8 TeV. An excess of $B^+ \to p \bar\Lambda$
candidates with respect to background expectations is seen with a statistical
significance of 4.1 standard deviations, and constitutes the first evidence for
this decay. The branching fraction, measured using the $B^+ \to K^0_{\mathrm S}
\pi^+$ decay for normalisation, is \begin{eqnarray} \mathcal{B}(B^+ \to p
\bar\Lambda) & = & ( 2.4 \,^{+1.0}_{-0.8} \pm 0.3 ) \times 10^{-7} \,,
\nonumber \end{eqnarray} where the first uncertainty is statistical and the
second systematic.


title: Graphs, $\mathbb{F}_1$-schemes and virtual mixed Tate motives

abstract:
  In a number of recent works [6, 7] the authors have introduced and studied a
functor $\mathcal{F}_k$ which associates to each loose graph $\Gamma$ -which is
similar to a graph, but where edges with $0$ or $1$ vertex are allowed - a
$k$-scheme, such that $\mathcal{F}_k(\Gamma)$ is largely controlled by the
combinatorics of $\Gamma$. Here, $k$ is a field, and we allow $k$ to be
$\mathbb{F}_1$, the field with one element. For each finite prime field
$\mathbb{F}_p$, it is noted in [6] that any $\mathcal{F}_k(\Gamma)$ is
polynomial-count, and the polynomial is independent of the choice of the field.
In this note, we show that for each $k$, the class of $\mathcal{F}_k(\Gamma)$
in the Grothendieck ring $K_0(\texttt{Sch}_k)$ is contained in
$\mathbb{Z}[\mathbb{L}]$, the integral subring generated by the virtual
Lefschetz motive.


title: Learning Invariant Representations Of Planar Curves

abstract:
  We propose a metric learning framework for the construction of invariant
geometric functions of planar curves for the Eucledian and Similarity group of
transformations. We leverage on the representational power of convolutional
neural networks to compute these geometric quantities. In comparison with
axiomatic constructions, we show that the invariants approximated by the
learning architectures have better numerical qualities such as robustness to
noise, resiliency to sampling, as well as the ability to adapt to occlusion and
partiality. Finally, we develop a novel multi-scale representation in a
similarity metric learning paradigm.


title: Hardness of Liar's Domination on Unit Disk Graphs

abstract:
  A unit disk graph is the intersection graph of a set of unit diameter disks
in the plane. In this paper we consider liar's domination problem on unit disk
graphs, a variant of dominating set problem. We call this problem as {\it
Euclidean liar's domination problem}. In the Euclidean liar's domination
problem, a set ${\cal P}=\{p_1,p_2,\ldots,p_n\}$ of $n$ points (disk centers)
are given in the Euclidean plane. For $p \in {\cal P}$, $N[p]$ is a subset of
${\cal P}$ such that for any $q \in N[p]$, the Euclidean distance between $p$
and $q$ is less than or equal to 1, i.e., the corresponding unit diameter disks
intersect. The objective of the Euclidean liar's domination problem is to find
a subset $D\; (\subseteq {\cal P})$ of minimum size having the following
properties : (i) $|N[p_i] \cap D| \geq 2$ for $1 \leq i \leq n$, and (ii)
$|(N[p_i] \cup N[p_j]) \cap D| \geq 3$ for $i\neq j, 1\leq i,j \leq n$. This
article aims to prove the Euclidean liar's domination problem is NP-complete.


title:
A computable bound of the essential spectral radius of finite range
  Metropolis--Hastings kernels

abstract:
  Let $\pi$ be a positive continuous target density on $\mathbb{R}$. Let $P$ be
the Metropolis-Hastings operator on the Lebesgue space $\mathbb{L}^2(\pi)$
corresponding to a proposal Markov kernel $Q$ on $\mathbb{R}$. When using the
quasi-compactness method to estimate the spectral gap of $P$, a mandatory first
step is to obtain an accurate bound of the essential spectral radius
$r\_{ess}(P)$ of $P$. In this paper a computable bound of $r\_{ess}(P)$ is
obtained under the following assumption on the proposal kernel: $Q$ has a
bounded continuous density $q(x,y)$ on $\mathbb{R}^2$ satisfying the following
finite range assumption : $|u| \textgreater{} s \, \Rightarrow\, q(x,x+u) = 0$
(for some $s\textgreater{}0$). This result is illustrated with Random Walk
Metropolis-Hastings kernels.


title:
A dataset and exploration of models for understanding video data through
  fill-in-the-blank question-answering

abstract:
  While deep convolutional neural networks frequently approach or exceed
human-level performance at benchmark tasks involving static images, extending
this success to moving images is not straightforward. Having models which can
learn to understand video is of interest for many applications, including
content recommendation, prediction, summarization, event/object detection and
understanding human visual perception, but many domains lack sufficient data to
explore and perfect video models. In order to address the need for a simple,
quantitative benchmark for developing and understanding video, we present
MovieFIB, a fill-in-the-blank question-answering dataset with over 300,000
examples, based on descriptive video annotations for the visually impaired. In
addition to presenting statistics and a description of the dataset, we perform
a detailed analysis of 5 different models' predictions, and compare these with
human performance. We investigate the relative importance of language, static
(2D) visual features, and moving (3D) visual features; the effects of
increasing dataset size, the number of frames sampled; and of vocabulary size.
We illustrate that: this task is not solvable by a language model alone; our
model combining 2D and 3D visual information indeed provides the best result;
all models perform significantly worse than human-level. We provide human
evaluations for responses given by different models and find that accuracy on
the MovieFIB evaluation corresponds well with human judgement. We suggest
avenues for improving video models, and hope that the proposed dataset can be
useful for measuring and encouraging progress in this very interesting field.


title: Guruswami--Sudan List Decoding for Complex Reed--Solomon Codes

abstract:
  We analyze the Guruswami--Sudan list decoding algorithm for Reed--Solomon
codes over the complex field for sparse recovery in Compressed Sensing. We
propose methods of stabilizing both the interpolation and the root-finding
steps against numerical instabilities, where the latter is the most sensitive.
For this purpose, we modify the Roth--Ruckenstein algorithm and propose a
method to refine its result using Newton's method. The overall decoding
performance is then further improved using Generalized Minimum Distance
decoding based on intrinsic soft information. This method also allows to obtain
a unique solution of the recovery problem. The approach is numerically
evaluated and shown to improve upon recently proposed decoding techniques.


title: Static Analysis of Communicating Processes using Symbolic Transducers

abstract:
  We present a general model allowing static analysis based on abstract
interpretation for systems of communicating processes. Our technique, inspired
by Regular Model Checking, represents set of program states as lattice automata
and programs semantics as symbolic transducers. This model can express dynamic
creation/destruction of processes and communications. Using the abstract
interpretation framework, we are able to provide a sound over-approximation of
the reachability set of the system thus allowing us to prove safety properties.
We implemented this method in a prototype that targets the MPI library for C
programs.


title: Spin fluctuations and high-temperature superconductivity in cuprates

abstract:
  To describe the cuprate superconductors, models of strongly correlated
electronic systems, such as the Hubbard or t-J models, are commonly employed.
To study these models, projected (Hubbard) operators have to be used. Due to
the unconventional commutation relations for the Hubbard operators, a specific
kinematical interaction of electrons with spin and charge fluctuations emerges.
The interaction is induced by the intraband hopping with a coupling parameter
of the order of the kinetic energy of electrons W which is much larger than the
antiferromagnetic exchange interaction J induced by the interband hopping. This
review presents a consistent microscopic theory of spin excitations and
superconductivity for cuprates where these interactions are taken into account
within the Hubbard operator technique. The low-energy spin excitations are
considered for the t-J model, while the electronic properties are studied using
the two-subband extended Hubbard model where the intersite Coulomb repulsion V
and electron-phonon interaction are taken into account.


title: Local Decay for Weak Interactions with Massless Particles

abstract:
  We consider a mathematical model for the weak decay of the intermediate boson
$Z^0$ into neutrinos and antineutrinos. We prove that the total Hamiltonian has
a unique ground state in Fock space and we establish a limiting absorption
principle, local decay and a property of relaxation to the ground state for
initial states and observables suitably localized in energy and position. Our
proofs rest, in particular, on Mourre's theory and a low-energy decomposition.


title: Korchagin's third conjecture

abstract:
  We consider the $M$-curves of degree nine with three nests $1 \langle
\alpha_i \rangle, i = 1, 2, 3$ in $\mathbb{R}P^2$. After systematic
constructions, Korchagin conjectured that at least two of the $\alpha_i$ must
be odd. It was later proved that there is always one odd $\alpha_i$. We say
that the curve has a jump in a non-empty oval $O$ if there exist four ovals $A,
B, C, D$, with $A$ interior to some other non-empty oval $O'$, $D$ exterior,
$B, C$ interior to $O$, such that $B$ and $C$ are separated inside of $O$ by
any line passing through $A$ and $D$. In this paper, we prove the conjecture
for the curves without jump, and we find restrictions on the complex
orientations and rigid isotopy types admissible for the curves even, even, odd
with jump.


title: A posteriori error estimators for hierarchical B-spline discretizations

abstract:
  In this article we develop function-based a posteriori error estimators for
the solution of linear second order elliptic problems considering hierarchical
spline spaces for the Galerkin discretization.
  We prove a global upper bound for the energy error. The theory hinges on some
weighted Poincar\'e type inequalities, where the B-spline basis functions are
the weights appearing in the norms. Such inequalities are derived following the
lines in [Veeser and Verf\"urth, 2009], where the case of standard finite
elements is considered. Additionally, we present numerical experiments that
show the efficiency of the error estimators independently of the degree of the
splines used for discretization, together with an adaptive algorithm guided by
these local estimators that yields optimal meshes and rates of convergence,
exhibiting an excellent performance.


title: Self-averaging in the random 2D Ising ferromagnet

abstract:
  We study sample-to-sample fluctuations in a critical two-dimensional Ising
model with quenched random ferromagnetic couplings. Using replica calculations
in the renormalization group framework we derive explicit expressions for the
probability distribution function of the critical internal energy and for the
specific heat fluctuations. It is shown that the disorder distribution of
internal energies is Gaussian, and the typical sample-to-sample fluctuations as
well as the average value scale with the system size $L$ like $\sim L
\ln\ln(L)$. In contrast, the specific heat is shown to be self-averaging with a
distribution function that tends to a $\delta$-peak in the thermodynamic limit
$L \to \infty$. While previously a lack of self-averaging was found for the
free energy, we here obtain results for quantities that are directly measurable
in simulations, and implications for measurements in the actual lattice system
are discussed.


title:
Effect of the $\eta\eta$ channel and interference phenomena in the
  two-pion transitions of charmonia and bottomonia

abstract:
  The basic shape of di-pion mass spectra in the two-pion transitions of both
charmonia and bottomonia states is explained by an unified mechanism based on
contributions of the $\pi\pi$, $K\overline{K}$ and $\eta\eta$ coupled channels
including their interference. The role of the individual $f_0$ resonances in
shaping the di-pion mass distributions in the charmonia and bottomonia decays
is considered.


title: dMath: Distributed Linear Algebra for DL

abstract:
  The paper presents a parallel math library, dMath, that demonstrates leading
scaling when using intranode, internode, and hybrid-parallelism for deep
learning (DL). dMath provides easy-to-use distributed primitives and a variety
of domain-specific algorithms including matrix multiplication, convolutions,
and others allowing for rapid development of scalable applications like deep
neural networks (DNNs). Persistent data stored in GPU memory and advanced
memory management techniques avoid costly transfers between host and device.
dMath delivers performance, portability, and productivity to its specific
domain of support.


title:
Local variational study of 2d lattice energies and application to
  Lennard-Jones type interactions

abstract:
  In this paper, we focus on finite Bravais lattice energies per point in two
dimensions. We compute the first and second derivatives of these energies. We
prove that the Hessian at the square and the triangular lattice are diagonal
and we give simple sufficient conditions for the local minimality of these
lattices. Furthermore, we apply our result to Lennard--Jones type interacting
potentials that appear to be accurate in many physical and biological models.
The goal of this investigation is to understand how the minimum of the
Lennard--Jones lattice energy varies with respect to the density of the points.
Considering the lattices of fixed area A, we find the maximal open set to which
A must belong so that the triangular lattice is a minimizer (resp. a maximizer)
among lattices of area A. Similarly, we find the maximal open set to which A
must belong so that the square lattice is a minimizer (resp. a saddle point).
Finally, we present a complete conjecture, based on numerical investigations
and rigorous results among rhombic and rectangular lattices, for the minimality
of the classical Lennard--Jones energy per point with respect to its area. In
particular, we prove that the minimizer is a rectangular lattice if the area is
sufficiently large.


title: Local integrals of motion in the two-site Anderson-Hubbard model

abstract:
  It has been proposed that the states of fully many-body localized systems can
be described in terms of conserved local pseudospins. Due to the multitude of
ways to define these, the explicit identification of the optimally local
pseudospins in specific systems is non-trivial. Given continuing intense
interest in the role of disorder in strongly correlated systems, we consider
the disordered Hubbard model. Focusing on a two-site system, we track the
evolution of the optimally localized pseudospins as hopping and interactions
are varied to move the system away from the trivially localized atomic limit,
examining the explicit form of the pseudospins and exploring the broad
distribution of non-optimal forms.


title: The power index of a graph

abstract:
  The {\em power index} $\Theta(\Gamma)$ of a graph $\Gamma$ is the least order
of a group $G$ such that $\Gamma$ can embed into the power graph of $G$.
Furthermore, this group $G$ is {\em $\Gamma$-optimal} if $G$ has order
$\Theta(\Gamma)$. We say that $\Gamma$ is {\em power-critical} if its order
equals to $\Theta(\Gamma)$. This paper focuses on the power indices of complete
graphs, complete bipartite graphs and $1$-factors. We classify all
power-critical graphs $\Gamma'$ in these three families, and give a necessary
and sufficient condition for $\Gamma'$-optimal groups.


title: Central Exclusive Production in the STAR Experiment at RHIC

abstract:
  The STAR experiment at the Relativistic Heavy Ion Collider (RHIC) performs
studies of diffractive processes with the focus on the exclusive production of
particles in central range of rapidity. In 2015 STAR collected 18 pb$^{-1}$ of
data in polarized proton+proton collisions at $\sqrt{s}$=200 GeV to measure
Central Exclusive Production (CEP) process $pp\to pXp$ through Double Pomeron
Exchange (DPE) mechanism. The intact protons moving inside the RHIC beampipe
after the collision were measured in silicon strip detectors (SSD), which were
placed in the Roman Pot vessels. This enables full control over interaction
kinematics and verification of the exclusivity of the reaction by measuring the
total (missing) transverse momenta of all final state particles: the central
diffractive system in the Time Projection Chamber (TPC) and the forward protons
in the Roman Pots. With the use of ionization energy loss in the TPC,
d$E$/d$x$, it was possible to discriminate various production channels in
$pp\to pXp$ reaction. This paper presents results on exclusive production of
two charged particles ($\pi^{+}\pi^{-}$ and $K^{+}K^{-}$) in mid-rapidity
region, $-1<\eta<1$, with small squared four-momentum transfer of forward
protons, $0.03<-t<0.3~(\textrm{GeV}/c)^{2}$, obtained using 2.5% of full
statistics.


title:
SimAthens: A spatial microsimulation approach to the estimation and
  analysis of small-area income distributions and poverty rates in Athens,
  Greece

abstract:
  Published during a severe economic crisis, this study presents the first
spatial microsimulation model for the analysis of income inequalities and
poverty in Greece. First, we present a brief overview of the method and discuss
its potential for the analysis of multidimensional poverty and income
inequality in Greece. We then present the SimAthens model, based on a
combination of small-area demographic and socioeconomic information available
from the Greek census of population with data from the European Union
Statistics on Income and Living Conditions (EU-SILC). The model is based on an
iterative proportional fitting (IPF) algorithm, and is used to reweigh EU-SILC
records to fit in small-area descriptions for Athens based on 2001 and 2011
censuses. This is achieved by using demographic and socioeconomic
characteristics as constraint variables. Finally, synthesis of the labor market
and occupations are chosen as the main variables for externally validating our
results, in order to verify the integrity of the model. Results of this
external validation process are found to be extremely satisfactory, indicating
a high goodness of fit between simulated and real values. Finally, the study
presents a number of model outputs, illustrating changes in social and economic
geography, during a severe economic crisis, offering a great opportunity for
discussing further potential of this model in policy analysis.


title: Robust DEA efficiency scores: A probabilistic/combinatorial approach

abstract:
  In this paper we propose robust efficiency scores for the scenario in which
the specification of the inputs/outputs to be included in the DEA model is
modelled with a probability distribution. This proba- bilistic approach allows
us to obtain three different robust efficiency scores: the Conditional Expected
Score, the Unconditional Expected Score and the Expected score under the
assumption of Maximum Entropy principle. The calculation of the three
efficiency scores involves the resolution of an exponential number of linear
problems. The algorithm presented in this paper allows to solve over 200
millions of linear problems in an affordable time when considering up 20
inputs/outputs and 200 DMUs. The approach proposed is illustrated with an
application to the assessment of professional tennis players.


title:
A generalization of the concept of distance based on the simplex
  inequality

abstract:
  We introduce and discuss the concept of \emph{$n$-distance}, a generalization
to $n$ elements of the classical notion of distance obtained by replacing the
triangle inequality with the so-called simplex inequality $$ d(x_1, \ldots,
x_n)~\leq~K\, \sum_{i=1}^n d(x_1, \ldots, x_n)_i^z{\,}, \qquad x_1, \ldots,
x_n, z \in X, $$ where $K=1$. Here $d(x_1,\ldots,x_n)_i^z$ is obtained from the
function $d(x_1,\ldots,x_n)$ by setting its $i$th variable to $z$. We provide
several examples of $n$-distances, and for each of them we investigate the
infimum of the set of real numbers $K\in\left]0,1\right]$ for which the
inequality above holds. We also introduce a generalization of the concept of
$n$-distance obtained by replacing in the simplex inequality the sum function
with an arbitrary symmetric function.


title: Observability of Inert Scalars at the LHC

abstract:
  In this work we investigate the observability of Inert Doublet Model scalars
at the LHC operating at the center of mass energy of 14 TeV. The signal
production process is $pp \to AH^\pm \to ZHW^{\pm}H$ leading to two different
final states of $\ell^+\ell^-Hjj H$ and $\ell^+\ell^-H\ell^\pm\nu H$ based on
the hadronic and leptonic decay channels of the W boson. All the relevant
background processes are considered and an event selection is designed to
distinguish the signal from the large Standard Model background. We found that
signals of the selected search channels are well observable at the LHC with
integrated luminosity of 300 fb$^{-1}$.


title: Coarse-to-Fine Volumetric Prediction for Single-Image 3D Human Pose

abstract:
  This paper addresses the challenge of 3D human pose estimation from a single
color image. Despite the general success of the end-to-end learning paradigm,
top performing approaches employ a two-step solution consisting of a
Convolutional Network (ConvNet) for 2D joint localization and a subsequent
optimization step to recover 3D pose. In this paper, we identify the
representation of 3D pose as a critical issue with current ConvNet approaches
and make two important contributions towards validating the value of end-to-end
learning for this task. First, we propose a fine discretization of the 3D space
around the subject and train a ConvNet to predict per voxel likelihoods for
each joint. This creates a natural representation for 3D pose and greatly
improves performance over the direct regression of joint coordinates. Second,
to further improve upon initial estimates, we employ a coarse-to-fine
prediction scheme. This step addresses the large dimensionality increase and
enables iterative refinement and repeated processing of the image features. The
proposed approach outperforms all state-of-the-art methods on standard
benchmarks achieving a relative error reduction greater than 30% on average.
Additionally, we investigate using our volumetric representation in a related
architecture which is suboptimal compared to our end-to-end approach, but is of
practical interest, since it enables training when no image with corresponding
3D groundtruth is available, and allows us to present compelling results for
in-the-wild images.


title: A General Theory of Information and Computation

abstract:
  This paper fills a gap in our understanding of the interaction between
information and computation. It unifies other approaches to measuring
information like Kolmogorov complexity and Shannon information. We define a
theory about information flow in deterministic computing based on three
fundamental observations: 1) Information is measured in logarithms, 2) All
countable sets contain the same amount of information and 3) Deterministic
computing does not create information. We analyze the flow of information
through computational processes: exactly, for primitive recursive functions and
elementary artithmetical operations and, under maximal entropy, for polynomial
functions and diophantine equations. Thus we get, by the MRDP-theorem, a theory
of flow of information for general computable functions. We prove some results
like the Fueter-P\'olya conjecture and the existence of an information
conserving enumeration of all finite sets of numbers. We also show that the
information flow in more complex derivatives of the primitive recursive
functions like addition and multiplication is not trivial: in particular
associativity is not information efficient for addition. Using the Cantor
pairing function we develop a universal measuring device for partitions of the
set of finite sets of numbers. We show that these sets can be enumerated by a
polynomial function when ordered by cardinality, but not when ordered by their
sums.


title: On the definition of spacetimes in Noncommutative Geometry, Part I

abstract:
  In this two-part paper we propose an extension of Connes' notion of even
spectral triple to the Lorentzian setting. This extension, which we call a
spectral spacetime, is discussed in part II where several natural examples are
given which are not covered by the previous approaches to the problem. Part I
only deals with the commutative and continuous case of a manifold. It contains
all the necessary material for the generalization to come in part II, namely
the characterization of the signature of the metric in terms of a
time-orientation 1-form and a natural Krein product on spinor fields. It turns
out that all the data available in Noncommutative Geometry (the algebra of
functions, the Krein space of spinor fields, the representation of the algebra
on it, the Dirac operator, charge conjugation and chirality), but nothing more,
play a role in this characterization. Thus, only space and time oriented spin
manifolds of even dimension are considered for a noncommutative generalization
in this approach. We observe that these are precisely the kind of manifolds on
which the modern theories of spacetime and matter are defined.


title: Visual motion processing and human tracking behavior

abstract:
  The accurate visual tracking of a moving object is a human fundamental skill
that allows to reduce the relative slip and instability of the object's image
on the retina, thus granting a stable, high-quality vision. In order to
optimize tracking performance across time, a quick estimate of the object's
global motion properties needs to be fed to the oculomotor system and
dynamically updated. Concurrently, performance can be greatly improved in terms
of latency and accuracy by taking into account predictive cues, especially
under variable conditions of visibility and in presence of ambiguous retinal
information. Here, we review several recent studies focusing on the integration
of retinal and extra-retinal information for the control of human smooth
pursuit.By dynamically probing the tracking performance with well established
paradigms in the visual perception and oculomotor literature we provide the
basis to test theoretical hypotheses within the framework of dynamic
probabilistic inference. We will in particular present the applications of
these results in light of state-of-the-art computer vision algorithms.


title:
AARC: First draft of the Blueprint Architecture for Authentication and
  Authorisation Infrastructures

abstract:
  AARC (Authentication and Authorisation for Research Communities) is a
two-year EC-funded project to develop and pilot an integrated cross-discipline
authentication and authorisation framework, building on existing authentication
and authorisation infrastructures (AAIs) and production federated
infrastructure. AARC also champions federated access and offers tailored
training to complement the actions needed to test AARC results and to promote
AARC outcomes. This article describes a high-level blueprint architectures for
interoperable AAIs.