title:
Measurement of double-differential muon neutrino charged-current
  interactions on C$_8$H$_8$ without pions in the final state using the T2K
  off-axis beam

abstract:
  We report the measurement of muon neutrino charged-current interactions on
carbon without pions in the final state at the T2K beam energy using
5.734$\times10^{20}$ protons on target. For the first time the measurement is
reported as a flux-integrated, double-differential cross-section in muon
kinematic variables ($\cos\theta_\mu$, $p_\mu$), without correcting for events
where a pion is produced and then absorbed by final state interactions. Two
analyses are performed with different selections, background evaluations and
cross-section extraction methods to demonstrate the robustness of the results
against biases due to model-dependent assumptions. The measurements compare
favorably with recent models which include nucleon-nucleon correlations but,
given the present precision, the measurement does not solve the degeneracy
between different models. The data also agree with Monte Carlo simulations
which use effective parameters that are tuned to external data to describe the
nuclear effects. The total cross-section in the full phase space is $\sigma =
(0.417 \pm 0.047 \text{(syst)} \pm 0.005 \text{(stat)})\times 10^{-38}
\text{cm}^2$ $\text{nucleon}^{-1}$ and the cross-section integrated in the
region of phase space with largest efficiency and best signal-over-background
ratio ($\cos\theta_\mu>0.6$ and $p_\mu > 200$ MeV) is $\sigma = (0.202 \pm
0.0359 \text{(syst)} \pm 0.0026 \text{(stat)}) \times 10^{-38} \text{cm}^2$
$\text{nucleon}^{-1}$.


title: Diphoton Excess and Running Couplings

abstract:
  The recently observed diphoton excess at the LHC may suggest the existence of
a singlet (pseudo-) scalar particle with a mass of 750 GeV which couples to
gluons and photons. Assuming that the couplings to gluons and photons originate
from loops of fermions and/or scalars charged under the Standard Model gauge
groups, we show that here is a model-independent upper bound on the cross
section $\sigma(pp\to S\to \gamma\gamma)$ as a function of the cutoff scale
$\Lambda$ and masses of the fermions and scalars in the loop. Such a bound
comes from the fact that the contribution of each particle to the diphoton
event amplitude is proportional to its contribution to the one-loop $\beta$
functions of the gauge couplings. We also investigate the perturbativity of
running Yukawa couplings in models with fermion loops, and show the upper
bounds on $\sigma(pp\to S\to \gamma\gamma)$ for explicit models.


title:
Enabling UAV Cellular with Millimeter-Wave Communication: Potentials and
  Approaches

abstract:
  To support high data rate urgent or ad hoc communications, we consider mmWave
UAV cellular networks and the associated challenges and solutions. To enable
fast beamforming training and tracking, we first investigate a hierarchical
structure of beamforming codebooks and design of hierarchical codebooks with
different beam widths via the sub-array techniques. We next examine the Doppler
effect as a result of UAV movement and find that the Doppler effect may not be
catastrophic when high gain directional transmission is used. We further
explore the use of millimeter wave spatial division multiple access and
demonstrate its clear advantage in improving the cellular network capacity. We
also explore different ways of dealing with signal blockage and point out that
possible adaptive UAV cruising algorithms would be necessary to counteract
signal blockage. Finally, we identify a close relationship between UAV
positioning and directional millimeter wave user discovery, where update of the
former may directly impact the latter and vice versa.


title: Multi-Unit Facility Location Games

abstract:
  Facility location games have been a topic of major interest in economics,
operations research and computer science, starting from the seminal work by
Hotelling. In the classical pure location Hotelling game businesses compete for
maximizing customer attraction by strategically locating their facilities,
assuming no price competition, while customers are attracted to their closest
facilities. Surprisingly, very little rigorous work has been presented on
multi-unit facility location games, where the classical pure location Hotelling
games are extended to contexts where each player is to locate several
facilities. In this paper we present two major contributions to the study of
multi-unit pure location Hotelling games. In the first part of this paper we
deal with the two-player multi-unit setting, and fully characterize its
equilibria. In the second part of this paper we deal with multi-unit facility
location games, with $N\geq 3$ players; our main result in this part is the
full characterization of the settings where pure strategy equilibria exist. Our
results also extend classical results on necessary and sufficient conditions
for a strategy profile to be in equilibrium in a pure location (single-unit)
Hotelling game to multi-unit pure location games.


title: Optical study of the vibrational and dielectric properties of BiMnO3

abstract:
  BiMnO3 (BMO), ferromagnetic (FM) below Tc = 100 K, was believed to be also
ferroelectric (FE) due to a non-centro-symmetric C2 structure, until
diffraction data indicated that its space group is the centro-symmetric C2/c.
Here we present infrared phonon spectra of BMO, taken on a mosaic of single
crystals, which are consistent with C2/c at any T > 10 K, as well as
room-temperature Raman data which strongly support this conclusion. We also
find that the infrared intensity of several phonons increases steadily for
decreasing T, causing the relative permittivity of BMO to vary from 18.5 at 300
K to 45 at 10 K. At variance with FE materials of displacive type, no
appreciable softening has been found in the infrared phonons. Both their
frequencies and intensities, moreover, appear insensitive to the FM transition
at Tc.


title:
Symmetries and martingales in a stochastic model for the Navier-Stokes
  equation

abstract:
  A stochastic description of solutions of the Navier-Stokes equation is
investigated. These solutions are represented by laws of finite dimensional
semi-martingales and characterized by a weak Euler- Lagrange condition. A least
action principle, related to the relative entropy, is provided. Within this
stochastic framework, by assuming further symmetries, the corresponding
invariances are expressed by martingales, stemming from a weak Noether's
theorem.


title:
A randomized maximum a posterior method for posterior sampling of high
  dimensional nonlinear Bayesian inverse problems

abstract:
  We present a randomized maximum a posteriori (rMAP) method for generating
approximate samples of posteriors in high dimensional Bayesian inverse problems
governed by large-scale forward problems. We derive the rMAP approach by: 1)
casting the problem of computing the MAP point as a stochastic optimization
problem; 2) interchanging optimization and expectation; and 3) approximating
the expectation with a Monte Carlo method. For a specific randomized data and
prior mean, rMAP reduces to the maximum likelihood approach (RML). It can also
be viewed as an iterative stochastic Newton method. An analysis of the
convergence of the rMAP samples is carried out for both linear and nonlinear
inverse problems. Each rMAP sample requires solution of a PDE-constrained
optimization problem; to solve these problems, we employ a state-of-the-art
trust region inexact Newton conjugate gradient method with sensitivity-based
warm starts. An approximate Metropolization approach is presented to reduce the
bias in rMAP samples. Various numerical methods will be presented to
demonstrate the potential of the rMAP approach in posterior sampling of
nonlinear Bayesian inverse problems in high dimensions.


title:
Numerical invariants of Fano schemes of linear subspaces on complete
  intersections

abstract:
  The goal of this paper is to explore the genus and degree of the Fano scheme
of linear subspaces on a complete intersection in a complex projective space.
Firstly, suppose that the expected dimension of the Fano scheme is one, we
prove a genus-degree formula. Secondly, we give a degree formula for the Fano
scheme.


title: Scattering on magnetic skyrmion in the non-adiabatic approximation

abstract:
  We present a theory of electron scattring on a magnetic skyrmion for the case
when exchange interaction is moderate so that adiabatic approximation and Berry
phase approach is not applicable. The theory explains the appearance of a
topological Hall current in the systems with magnetic skyrmions, of a special
importance its applicability to dilute magnetic semiconductors with a weak
exchange interaction.


title:
On the emergence of syntactic structures: quantifying and modelling
  duality of patterning

abstract:
  The complex organization of syntax in hierarchical structures is one of the
core design features of human language. Duality of patterning refers for
instance to the organization of the meaningful elements in a language at two
distinct levels: a combinatorial level where meaningless forms are combined
into meaningful forms and a compositional level where meaningful forms are
composed into larger lexical units. The question remains wide open regarding
how such a structure could have emerged. Furthermore a clear mathematical
framework to quantify this phenomenon is still lacking. The aim of this paper
is that of addressing these two aspects in a self-consistent way. First, we
introduce suitable measures to quantify the level of combinatoriality and
compositionality in a language, and present a framework to estimate these
observables in human natural languages. Second, we show that the theoretical
predictions of a multi-agents modeling scheme, namely the Blending Game, are in
surprisingly good agreement with empirical data. In the Blending Game a
population of individuals plays language games aiming at success in
communication. It is remarkable that the two sides of duality of patterning
emerge simultaneously as a consequence of a pure cultural dynamics in a
simulated environment that contains meaningful relations, provided a simple
constraint on message transmission fidelity is also considered.


title: Sieves and the Minimal Ramification Problem

abstract:
  The minimal ramification problem may be considered as a quantitative version
of the inverse Galois problem. For a nontrivial finite group $G$, let $m(G)$ be
the minimal integer $m$ for which there exists a Galois extension
$N/\mathbb{Q}$ that is ramified at exactly $m$ primes (including the infinite
one). So, the problem is to compute or to bound $m(G)$.
  In this paper, we bound the ramification of extensions $N/\mathbb{Q}$
obtained as a specialization of a branched covering $\phi\colon C\to
\mathbb{P}^1_{\mathbb{Q}}$. This leads to novel upper bounds on $m(G)$, for
finite groups $G$ that are realizable as the Galois group of a branched
covering. Some instances of our general results are: $$ 1\leq m(S_m)\leq 4
\quad \mbox{and} \quad n\leq m(S_m^n) \leq n+4, $$ for all $n,m>0$. Here $S_m$
denotes the symmetric group on $m$ letters, and $S_m^n$ is the direct product
of $n$ copies of $S_m$. We also get the correct asymptotic of $m(G^n)$, as $n
\to \infty$ for a certain class of groups $G$.
  Our methods are based on sieve theory results, in particular on the
Green-Tao-Ziegler theorem on prime values of linear forms in two variables, on
the theory of specialization in arithmetic geometry, and on finite group
theory.


title: Extremal results for odd cycles in sparse pseudorandom graphs

abstract:
  We consider extremal problems for subgraphs of pseudorandom graphs. For
graphs $F$ and $\Gamma$ the generalized Tur\'an density $\pi_F(\Gamma)$ denotes
the density of a maximum subgraph of $\Gamma$, which contains no copy of~$F$.
Extending classical Tur\'an type results for odd cycles, we show that
$\pi_{F}(\Gamma)=1/2$ provided $F$ is an odd cycle and $\Gamma$ is a
sufficiently pseudorandom graph. In particular, for $(n,d,\lambda)$-graphs
$\Gamma$, i.e., $n$-vertex, $d$-regular graphs with all non-trivial eigenvalues
in the interval $[-\lambda,\lambda]$, our result holds for odd cycles of length
$\ell$, provided \[ \lambda^{\ell-2}\ll
\frac{d^{\ell-1}}n\log(n)^{-(\ell-2)(\ell-3)}\,. \] Up to the polylog-factor
this verifies a conjecture of Krivelevich, Lee, and Sudakov. For triangles the
condition is best possible and was proven previously by Sudakov, Szab\'o, and
Vu, who addressed the case when $F$ is a complete graph. A construction of Alon
and Kahale (based on an earlier construction of Alon for triangle-free
$(n,d,\lambda)$-graphs) shows that our assumption on $\Gamma$ is best possible
up to the polylog-factor for every odd $\ell\geq 5$.


title:
Identifying top football players and springboard clubs from a football
  player collaboration and club transfer networks

abstract:
  We consider all players and clubs in top twenty world football leagues in the
last fifteen seasons. The purpose of this paper is to reveal top football
players and identify springboard clubs. To do that, we construct two separate
weighted networks. Player collaboration network consists of players, that are
connected to each other if they ever played together at the same club. In
directed club transfer network, clubs are connected if players were ever
transferred from one club to another. To get meaningful results, we perform
different network analysis methods on our networks. Our approach based on
PageRank reveals Christiano Ronaldo as the top player. Using a variation of
betweenness centrality, we identify Standard Liege as the best springboard
club.


title:
History and Development of Coronal Mass Ejections as a Key Player in
  Solar Terrestrial Relationship

abstract:
  Coronal mass ejections (CMEs) are relatively a recently-discovered
phenomenon, in 1971, some fifteen years into the Space Era. It took another two
decades to realize that CMEs are the most important players in solar
terrestrial relationship as the root cause of severe weather in Earth's space
environment. CMEs are now counted among the major natural hazards because they
cause large solar energetic particle (SEP) events and major geomagnetic storms,
both of which pose danger to humans and their technology in space and ground.
Geomagnetic storms discovered in the 1700s, solar flares discovered in the
1800s, and SEP events discovered in the1900s are all now found to be closely
related to CMEs via various physical processes occurring at various locations
in and around CMEs, when they interact with the ambient medium. This article
identifies a number of key developments that preceded the discovery of
white-light CMEs suggesting that CMEs were waiting to be discovered. The last
two decades witnessed an explosion of CME research following the launch of the
Solar and Heliospheric Observatory mission in 1995, resulting in the
establishment of a full picture of CMEs.


title: The Sun and its Planets as detectors for invisible matter

abstract:
  Gravitational lensing of invisible streaming matter towards the Sun could be
the explanation of the puzzling solar flares and the unexplained solar emission
in the EUV. Assuming that this invisible matter has some form of interaction
with normal matter and that there exist preferred directions in its flow, then
one would expect a more pronounced solar activity at certain planetary
heliocentric longitudes. This is best demonstrated in the case of the Earth and
the two inner planets. We have analyzed the solar flares as well as the EUV
emission. We observe statistically significant signals when one or more planets
have heliocentric longitudes mainly between 230o and 300o. We also analyzed
daily data of the global ionization degree of the Earth atmosphere. We observe
a correlation between the total atmospheric electron content and the orbital
position of the inner three planets. Remarkably, the strongest correlation is
appearing with the phase of the Moon.


title:
Asteroseismology of red-giant stars as a novel approach in the search
  for gravitational waves

abstract:
  Stars are massive resonators that may be used as gravitational-wave (GW)
detectors with isotropic sensitivity. New insights on stellar physics are being
made possible by asteroseismology, the study of stars by the observation of
their natural oscillations. The continuous monitoring of oscillation modes in
stars of different masses and sizes (e.g., as carried out by NASA's Kepler
mission) opens the possibility of surveying the local Universe for GW
radiation. Red-giant stars are of particular interest in this regard. Since the
mean separation between red giants in open clusters is small (a few light
years), this can in principle be used to look for the same GW imprint on the
oscillation modes of different stars as a GW propagates across the cluster.
Furthermore, the frequency range probed by oscillations in red giants
complements the capabilities of the planned eLISA space interferometer. We
propose asteroseismology of red giants as a novel approach in the search for
gravitational waves.


title:
Virilization of the Broad Line Region in Active Galactic Nuclei -
  connection between shifts and widths of broad emission lines

abstract:
  We investigate the virilization of the emission lines Hbeta and Mg II in the
sample of 287 Type 1 Active Galactic Nuclei taken from the Sloan Digital Sky
Survey database. We explore the connections between the intrinsic line shifts
and full widths at different levels of maximal intensity. We found that: (i)
Hbeta seems to be a good virial estimator of black hole masses, and an
intrinsic redshift of Hbeta is dominantly caused by the gravitational effect,
(ii) there is an anti-correlation between the redshift and width of the wings
of the Mg II line, (iii) the broad Mg II line can be used as virial estimator
only at 50% of the maximal intensity, while the widths and intrinsic shifts of
the line wings can not be used for this purpose.


title: On a correlation among azimuthal velocities and the flyby anomaly sign

abstract:
  Data of six flybys, those of Galileo I, Galileo II, NEAR, Cassini, Rosetta
and Messenger were reported by Anderson et al \citep{Anderson}. Four of them:
Galileo I, NEAR, Rosetta and Messenger gain Newtonian energy during the flyby
transfer, while Galileo II and Cassini lose energy. This is, in both cases, a
surprising anomaly since Newtonian forces derive from a potential and they are,
therefore, conservative. We show here that the gravitational field of a
rotating planet as derived from a new model introduces a non conservative force
that gives a partial, but in our opinion satisfactory, explanation of these
anomalies and suggests a correlation between the sign of the anomaly and the
sign of the azimuthal velocity at perigee.


title: Online Low-Rank Subspace Learning from Incomplete Data: A Bayesian View

abstract:
  Extracting the underlying low-dimensional space where high-dimensional
signals often reside has long been at the center of numerous algorithms in the
signal processing and machine learning literature during the past few decades.
At the same time, working with incomplete (partly observed) large scale
datasets has recently been commonplace for diverse reasons. This so called {\it
big data era} we are currently living calls for devising online subspace
learning algorithms that can suitably handle incomplete data. Their envisaged
objective is to {\it recursively} estimate the unknown subspace by processing
streaming data sequentially, thus reducing computational complexity, while
obviating the need for storing the whole dataset in memory. In this paper, an
online variational Bayes subspace learning algorithm from partial observations
is presented. To account for the unawareness of the true rank of the subspace,
commonly met in practice, low-rankness is explicitly imposed on the sought
subspace data matrix by exploiting sparse Bayesian learning principles.
Moreover, sparsity, {\it simultaneously} to low-rankness, is favored on the
subspace matrix by the sophisticated hierarchical Bayesian scheme that is
adopted. In doing so, the proposed algorithm becomes adept in dealing with
applications whereby the underlying subspace may be also sparse, as, e.g., in
sparse dictionary learning problems. As shown, the new subspace tracking scheme
outperforms its state-of-the-art counterparts in terms of estimation accuracy,
in a variety of experiments conducted on simulated and real data.


title: Splitting theorem for $\mathbb{Z}_2^n$-supermanifolds

abstract:
  Smooth $\mathbb{Z}_2^n$-supermanifolds have been introduced and studied
recently. The corresponding sign rule is given by the "scalar product" of the
involved $\mathbb{Z}_2^n$-degrees. It exhibits interesting changes in
comparison with the sign rule using the parity of the total degree. With the
new rule, nonzero degree even coordinates are not nilpotent, and even (resp.,
odd) coordinates do not necessarily commute (resp., anticommute) pairwise. The
classical Batchelor-Gawcedzki theorem says that any smooth supermanifold is
diffeomorphic to the "superization" $\Pi E$ of a vector bundle $E$. It is also
known that this result fails in the complex analytic category. Hence, it is
natural to ask whether an analogous statement goes through in the category of
$\mathbb{Z}_2^n$-supermanifolds with its local model made of formal power
series. We give a positive answer to this question.


title: Meromorphic Higgs bundles And Related Geometries

abstract:
  The present note is mostly a survey on the generalised Hitchin integrable
system and moduli spaces of meromorphic Higgs bundles. We also fill minor gaps
in the existing literature, outline a calculation of the infinitesimal period
map and review briefly some related geometries.


title:
Higher-Dimensional Unified Theories with continuous and fuzzy coset
  spaces as extra dimensions

abstract:
  We first briefly review the Coset Space Dimensional Reduction (CSDR)
programme and present the results of the best model so far, based on the
$\mathcal{N} = 1$, $d = 10$, $E_8$ gauge theory reduced over the
nearly-K\"ahler manifold $SU(3)/U(1)\times U(1)$. Then, we present the
adjustment of the CSDR programme in the case that the extra dimensions are
considered to be fuzzy coset spaces and then, the best model constructed in
this framework, too, which is the trinification GUT, $SU(3)^3$.


title: Analysis of friendship network from MMORPG based data

abstract:
  This work analyzes friendship network from a Massively Multiplayer Online
Role-Playing Game (MMORPG). The network is based on data from a private server
that was active from 2007 until 2011. The work conducts a standard analysis of
the network and then divides players according to different groups based on
their activity. Work checks how friendship network can be correlated to the
clan (a self-organized group of players who often form a league and play on the
same side in a match) network. Main part of the work is the recommendation
method for players that are not part of any clan and it is based on communities
of friendship network.


title: An elementary approach to certain bilinear estimates

abstract:
  We prove L2 x L2 to weak L1 estimates for some novel bilinear maximal
operators of Kakeya and lacunary type thus extending to this setting, the works
of Cordoba and of Nagel, Stein and Wainger.


title:
Modeling Cellular Networks in Fading Environments with Dominant Specular
  Components

abstract:
  Stochastic geometry (SG) has been widely accepted as a fundamental tool for
modeling and analyzing cellular networks. However, the fading models used with
SG analysis are mainly confined to the simplistic Rayleigh fading, which is
extended to the Nakagami-m fading in some special cases. However, neither the
Rayleigh nor the Nakagami-m accounts for dominant specular components (DSCs)
which may appear in realistic fading channels. In this paper, we present a
tractable model for cellular networks with generalized two-ray (GTR) fading
channel. The GTR fading explicitly accounts for two DSCs in addition to the
diffuse components and offers high flexibility to capture diverse fading
channels that appear in realistic outdoor/indoor wireless communication
scenarios. It also encompasses the famous Rayleigh and Rician fading as special
cases. To this end, the prominent effect of DSCs is highlighted in terms of
average spectral efficiency.


title:
Effects of quantum impurity spins on the magnetic properties of zigzag
  and linear spin chains

abstract:
  We investigated the magnetic ground state and low-energy excitations of the
spin chains compounds SrCuO$_{2}$ (zigzag chains) and Sr$_{2}$CuO$_{3}$ (linear
chains) in the presence of quantum impurities induced by lightly doping ($\leq
1 \%$) with Zn$^{2+}$ ($S = 0$), Co$^{2+}$ ($S =1/2$) and Ni$^{2+}$ ($S = 1$)
impurities at the Cu$^{2+}$ site. We show that the ground states and the nature
of low-lying excitations (i.e., gapped or gapless) depend on the spin state and
symmetry of the defects. For Ni doped chains a spin gap is observed but for Zn
and Co doping the excitations remain gapless. Co-doped chains exhibit magnetic
order with critical temperatures significantly enhanced compared to those of
the pristine compounds. In the specific case of 1 \% Co impurities, the linear
chains exhibit long-range order below 11 K, while the zigzag chain is
characterized by a quasi-long range ordered phase below 6 K with correlation
lengths of about 12\textit{a} and 40\textit{c} units along the crystal axes
\textit{a} and \textit{c}, respectively. The different magnetic behaviours of
these two compounds with comparable intra- and interchain couplings underpin
the role of spin frustration in the zigzag chains.


title: Exchange coupling inversion in a high-spin organic triradical molecule

abstract:
  The magnetic properties of a nanoscale system are inextricably linked to its
local environment. In ad-atoms on surfaces and inorganic layered structures the
exchange interactions result from the relative lattice positions, layer
thicknesses and other environmental parameters. Here, we report on a
sample-dependent sign inversion of the magnetic exchange coupling between the
three unpaired spins of an organic triradical molecule embedded in a
three-terminal device. This ferro-to-antiferromagnetic transition is due to
structural distortions and results in a high-to-low spin ground state change in
a molecule traditionally considered to be a robust high-spin quartet. Moreover,
the flexibility of the molecule yields an in-situ electric tunability of the
exchange coupling via the gate electrode. These findings open a route to the
controlled reversal of the magnetic states in organic molecule-based
nanodevices by mechanical means, electrical gating or chemical tailoring.


title:
On the existence of infinitely many closed geodesics on non-compact
  manifolds

abstract:
  We prove that any complete (and possibly non-compact) Riemannian manifold $M$
possesses infinitely many closed geodesics provided its free loop space has
unbounded Betti numbers in degrees larger than the dimension of $M$, and there
are no close conjugate points at infinity. Our argument builds on an existence
result due to Benci and Giannoni, and generalizes the celebrated theorem of
Gromoll and Meyer for closed manifolds.


title:
The spectroscopic imprint of the pre-eruptive configuration resulting
  into two major coronal mass ejections

abstract:
  We present a spectroscopic analysis of the pre-eruptive configuration of
active region NOAA 11429, prior to two very fast coronal mass ejections (CMEs)
on March 7, 2012 that are associated with this active region. We study the
thermal components and the dynamics associated with the ejected flux ropes.
Using differential emission measure (DEM) analysis of Hinode/EIS and SDO/AIA
observations, we identify the emission components of both the flux rope and the
host active region. We then follow the time evolution of the flux rope emission
components by using AIA observations. The plasma density and the Doppler and
non-thermal velocities associated with the flux ropes are also calculated from
the EIS data. The eastern and western parts of the active region, in which the
two different fast CMEs originated during two X-class flares, were studied
separately. In both regions we identified an emission component in the
temperature range of $\log T=6.8 - 7.1$ associated with the presence of flux
ropes. The time evolution of the eastern region showed an increase in the mean
DEM in this temperature range by an order of magnitude, 5 hours prior to the
first CME. This was associated with a gradual rise and heating of the flux rope
as manifested by blue-shifts and increased non-thermal velocities in
\ion{Ca}{XV}~200.97\AA, respectively. An overall upward motion of the flux
ropes was measured (relative blue-shifts of $\sim12$~\kms). The measured
electron density was found to be $4\times 10^9 - 2 \times10^{10}$ cm$^{-3}$
(using the ratio of \ion{Ca}{XV}~181.90\AA\ over \ion{Ca}{XV}~200.97\AA). We
compare our findings with other works on the same AR to provide a unified
picture of its evolution.


title: Package equivalence in complex software network

abstract:
  The public package registry npm is one of the biggest software registry. With
its 216 911 software packages, it forms a big network of software dependencies.
In this paper we evaluate various methods for finding similar packages in the
npm network, using only the structure of the graph. Namely, we want to find a
way of categorizing similar packages, which would be useful for recommendation
systems. This size enables us to compute meaningful results, as it softened the
particularities of the graph. Npm is also quite famous as it is the default
package repository of Node.js. We believe that it will make our results
interesting for more people than a less used package repository. This makes it
a good subject of analysis of software networks.


title:
NA61/SHINE results on fluctuations and correlations in p+p and Be+Be
  interactions at CERN SPS energies

abstract:
  The aim of the NA61/SHINE strong interaction program is to explore the phase
diagram of strongly interacting matter. The main physics goals are the study of
the onset of deconfinement and the search for the critical point of strongly
interacting matter. These goals are pursued by performing a beam momentum
(13$A$ - 158$A$ GeV/c) and system size (p+p, p+Pb, Be+Be, Ar+Sc, Xe+La) scan.
  This contribution presents results on transverse momentum and multiplicity
fluctuations from the Be+Be and p+p energy scan. Also, results on two-particle
correlations in pseudorapidity and azimuthal angle obtained in p+p interactions
will be shown. The influence of conservation laws and resonance decays on
multiplicity and chemical fluctuations of identified particles in p+p
interactions will be discussed. Obtained results will be compared with data
from other experiments and with model predictions.


title: A Universal Approximation Theorem for Mixture of Experts Models

abstract:
  The mixture of experts (MoE) model is a popular neural network architecture
for nonlinear regression and classification. The class of MoE mean functions is
known to be uniformly convergent to any unknown target function, assuming that
the target function is from Sobolev space that is sufficiently differentiable
and that the domain of estimation is a compact unit hypercube. We provide an
alternative result, which shows that the class of MoE mean functions is dense
in the class of all continuous functions over arbitrary compact domains of
estimation. Our result can be viewed as a universal approximation theorem for
MoE models.


title:
A non-supersymmetric model with unification of electro-weak and strong
  interactions

abstract:
  In this note we present an example of an extension of the Standard Model
where unification of strong and electroweak interactions occurs at a level
comparable to that occurring in the minimal supersymmetric standard model.


title:
Temporal structure of attosecond pulses from laser-driven coherent
  synchrotron emission

abstract:
  The microscopic dynamics of laser-driven coherent synchrotron emission
transmitted through thin foils are investigated using particle-in-cell
simulations. For normal incidence interactions, we identify the formation of
two distinct electron nanobunches from which emission takes place each
half-cycle of the driving laser pulse. These emissions are separated temporally
by 130 attoseconds and are dominant in different frequency ranges, which is a
direct consequence of the distinct characteristics of each electron nanobunch.
This may be exploited through spectral filtering to isolate these emissions,
generating electromagnetic pulses of duration ~70 as.


title:
Medical Concept Representation Learning from Electronic Health Records
  and its Application on Heart Failure Prediction

abstract:
  Objective: To transform heterogeneous clinical data from electronic health
records into clinically meaningful constructed features using data driven
method that rely, in part, on temporal relations among data. Materials and
Methods: The clinically meaningful representations of medical concepts and
patients are the key for health analytic applications. Most of existing
approaches directly construct features mapped to raw data (e.g., ICD or CPT
codes), or utilize some ontology mapping such as SNOMED codes. However, none of
the existing approaches leverage EHR data directly for learning such concept
representation. We propose a new way to represent heterogeneous medical
concepts (e.g., diagnoses, medications and procedures) based on co-occurrence
patterns in longitudinal electronic health records. The intuition behind the
method is to map medical concepts that are co-occuring closely in time to
similar concept vectors so that their distance will be small. We also derive a
simple method to construct patient vectors from the related medical concept
vectors. Results: For qualitative evaluation, we study similar medical concepts
across diagnosis, medication and procedure. In quantitative evaluation, our
proposed representation significantly improves the predictive modeling
performance for onset of heart failure (HF), where classification methods (e.g.
logistic regression, neural network, support vector machine and K-nearest
neighbors) achieve up to 23% improvement in area under the ROC curve (AUC)
using this proposed representation. Conclusion: We proposed an effective method
for patient and medical concept representation learning. The resulting
representation can map relevant concepts together and also improves predictive
modeling performance.


title:
Drude weight in hard core Boson systems: possibility of a finite
  temperature ideal conductor

abstract:
  We calculate the Drude weight in the superfluid (SF) and the supersolid (SS)
phases of hard core boson (HCB) model using stochastic series expansion (SSE).
We demonstrate from our numerical calculations that the normal phase of HCBs in
two dimensions can be an ideal conductor with dissipationless transport. In two
dimensions, when the ground state is a SF, the superfluid stiffness drops to
zero with a Kosterlitz-Thouless type transition at $T_{KT}$. The Drude weight,
though is equal to the stiffness below $T_{KT}$, surprisingly stays finite even
for temperatures above $T_{KT}$ indicating the non-dissipative transport in the
normal state of this system. In contrast to this in a three dimensional SF
phase, where the superfluid stiffness goes to zero continuously with a second
order phase transition at $T_c$, Drude weight also goes to zero at $T_c$ as
expected. We also calculated the Drude weight in a 2D SS phase, where the
charge density wave (CDW) order coexists with superfluidity. For the SS phase
we studied, superfluidity is lost via Kosterlitz-Thouless transition at
$T_{KT}$ and the transition temperature for the CDW order is larger than
$T_{KT}$. In striped SS phase where the CDW order breaks the rotational
symmetry of the lattice, for $T > T_{KT}$, the system behaves like an ideal
conductor along one of the lattice direction while along the other direction it
behaves like an insulator. In contrast to this, in star-SS phase, Drude weight
along both the lattice directions goes to zero along with the superfluid
stiffness and for $T > T_{KT}$ we have a finite temperature phase of a CDW
insulator.


title: Gravitational Redshift of Emission Lines in the AGN Spectra

abstract:
  The detection of gravitationally redshifted optical emission lines has been
reported just for a few active galaxies. In this paper we give a short overview
of studies that analyzed or exploited the detection of the gravitational
redshift in optical AGN spectra. In addition, we tested the consistency of
gravitational redshift as the physical origin of the redward shifts observed in
their spectra using a sample of $\approx$ 50 Hamburg-ESO intermediate to high
redshift quasars that are among the most luminous quasars known ($10^{47}
\lesssim L \lesssim 10^{48}$ erg/s), and are expected to host very massive
black holes. To this aim we modeled the line profile with accretion disk models
around a black hole.


title:
Analytic Methods to Calculate Fault Trees with Loops - Restrictions of
  Application and Solution Uniqueness

abstract:
  One of the important tasks of the Reliability Estimation is Analysis of the
Fault Tree. A problem of Fault Trees analysis is considered one of the most
complex ones, since structure of such trees is characterized by a considerable
number of interconnections. Usually analytical methods are used and most
applicable method is Minimal Cut Sets building and calculation. Classical Fault
Tree Analysis methods are applicable only for Fault Trees without loops. Loops
can appear in Fault Tree, when a TOP or some intermediate gates appear as input
to another gate at a lower level of the model. An occurrence of a Loop has been
a problematic issue in a Fault Tree calculation. The article relates to the
uniqueness of the solution for the Fault Trees with arbitrary Loops. There are
assumed, that failures of the Basic Events are non-repairable and Fault Tree
gates may be expressed by two main logic gates.


title: Constructing a weak subset of a random set

abstract:
  The tree forcing method given by (Liu 2015) enables the cone avoiding of
strong enumeration of a given tree, within a subset or co-subset of an
arbitrary given set, provided the given tree does not admit computable strong
enumeration. Using this result, we settled and reproduced a series of problems
in reverse mathematics. In this paper, we demonstrate cone avoiding results
within an infinite subset of a given 1-random set. We show that for any given
1-random set $X$, there exists an infinite subset $Y$ of $X$ such that $Y$ does
not compute any real with positive effective Hausdorff dimension, thus
answering negatively a question posed by Kjos-Hanssen that whether there exists
a 1-random set of which any infinite subset computes some 1-random real. The
result is surprising in that the tree forcing technique used on the subset or
co-subset seems to heavily rely on subset co-subset combinatorics, whereas this
result does not.


title:
Valley-enhanced fast relaxation of gate-controlled donor qubits in
  silicon

abstract:
  Gate control of donor electrons near interfaces is a generic ingredient of
donor-based quantum computing. Here, we address the question: how is the
phonon-assisted qubit relaxation time $T_1$ affected as the electron is
shuttled between the donor and the interface? We focus on the example of the
`flip-flop qubit' [Tosi et al., arXiv:1509.08538v1], defined as a combination
of the nuclear and electronic states of a phosphorous donor in silicon,
promising fast electrical control and long dephasing times when the electron is
halfway between the donor and the interface. We theoretically describe orbital
relaxation, flip-flop relaxation, and electron spin relaxation. We estimate
that the flip-flop qubit relaxation time can be of the order of $100 \,
\mu\text{s}$, 8 orders of magnitude shorter than the value for an on-donor
electron in bulk silicon, and a few orders of magnitude shorter (longer) than
the predicted inhomogeneous dephasing time (gate times). All three relaxation
processes are boosted by (i) the nontrivial valley structure of the
electron-phonon interaction, and (ii) the different valley compositions of the
involved electronic states.


title: Maximum Likelihood Estimation of Triangular and Polygonal Distributions

abstract:
  Triangular distributions are a well-known class of distributions that are
often used as elementary example of a probability model. In the past,
enumeration and order statistic-based methods have been suggested for the
maximum likelihood (ML) estimation of such distributions. A novel
parametrization of triangular distributions is presented. The parametrization
allows for the construction of an MM (minorization--maximization) algorithm for
the ML estimation of triangular distributions. The algorithm is shown to both
monotonically increase the likelihood evaluations, and be globally convergent.
Using the parametrization is then applied to construct an MM algorithm for the
ML estimation of polygonal distributions. This algorithm is shown to have the
same numerical properties as that of the triangular distribution. Numerical
simulation are provided to demonstrate the performances of the new algorithms
against established enumeration and order statistics-based methods.


title: Symmetries of Lorentzian Three-Manifolds with Recurrent Curvature

abstract:
  Locally homogeneous Lorentzian three-manifolds with recurrect curvature are
special examples of Walker manifolds, that is, they admit a parallel null
vector field. We obtain a full classification of the symmetries of these
spaces, with particular regard to symmetries related to their curvature: Ricci
and matter collineations, curvature and Weyl collineations. Several results are
given for the broader class of three-dimensional Walker manifolds.


title:
Search for extragalactic astrophysical counterparts of IceCube neutrino
  events

abstract:
  Detection of 54 very high-energy (VHE) neutrinos by the IceCube Neutrino
Observatory has opened a new chapter in multi-messenger astronomy. However due
to large errors in measuring the directions of the neutrino shower-type events,
which dominate the current event list, it is difficult to identify their
astrophysical sources. We perform cross-correlation study of IceCube neutrino
events with extragalactic candidate sources using X-ray and gamma-ray selected
source catalogues such as Swift-BAT, 3LAC and TeV-Cat. We apply different cuts
on the X-ray and gamma-ray fluxes of the sources in these catalogs, and use
different source classes in order to study correlation. We use invariant
statistic and Monte Carlo simulations to evaluate statistical significance of
any correlation.


title:
Local bursts model of primordial CMB temperature fluctuations:
  scattering in hydrogen lines

abstract:
  Within the framework of a flat cosmological model a propagation of an
instantaneous burst of isotropic radiation is considered from the moment of its
beginning at some initial redshift z0 to the moment of its registration now (at
z=0). Thomson scattering by free electrons and scattering in primordial
hydrogen lines Ha, Hb, Pa and Pb are considered as the sources of opacity and
when calculating an albedo of a single scattering in the lines we take into
account deactivation of the upper levels of transitions by background blackbody
radiation. Profiles for these lines in a burst spectrum are calculated for
different distances from the center of the burst and different values of z0. In
the first approximation these profiles do not depend on spectrum and intensity
of a burst radiation. It is shown that lines are in absorption at sufficiently
large distance but emission components may appear as a distance decreases and
it becomes stronger while absorption component weakens with a further distance
decrease. For the sum of Ha and Hb lines the depth of absorption can reach 2e-4
while for the sum of Pa and Pb lines the maximum absorption is about 7e-6. So
that the relative magnitude of temperature fluctuations lies between 1e-7 and
1e-9. The calculations were fulfiled for bursts with different initial sizes.
For the same z0 the profiles of hydrogen lines are practically coinside for
burst sizes lower than someone and for greater ones the lines weaken as the
burst size grows.


title:
Supersaturation and activity-rotation relation in PMS stars: the young
  Cluster h Per

abstract:
  The magnetic activity of late-type MS stars is characterized by different
regimes, and their activity levels are well described by Ro, the ratio between
P_rot and the convective turnover time. Very young PMS stars show, similarly to
MS stars, intense magnetic activity. However they do not show clear
activity-rotation trends, and it still debated which stellar parameters
determine their magnetic activity levels. To bridge the gap between MS and PMS
stars, we studied the activity-rotation relation in the young cluster h Per, a
~13 Myr old cluster, that contains both fast and slow rotators, whose members
have ended their accretion phase and have already developed a radiative core.
It offers us the opportunity to study the activity level of intermediate-age
PMS stars with different rotational velocities, excluding any interactions with
the circumstellar environment. We constrained the magnetic activity levels of h
Per members measuring their X-ray emission from a Chandra observation, while
P_rot were obtained by Moraux et al. (2013). We collected a final catalog of
414 h Per members with known P_rot, T_eff, M_star, with 169 of them having also
detected X-ray emission. We found that h Per members, with 1.0 M_sun < M_star <
1.4 M_sun, display different activity regimes: fast rotators show
supersaturation, while slower rotators have activity levels compatible to the
non-saturated regime. At 13 Myr h Per is therefore the youngest cluster showing
activity-rotation regimes analogous to that of MS stars, indicating that, at
this age, magnetic field production is likely regulated by the alpha-Omega type
dynamo. Moreover we observed that supersaturation is better described by P_rot
than Ro, and that the observed patterns are compatible with the hypothesis of
centrifugal stripping. In this scenario we inferred that coronae can produce
structures as large as ~2 R_star above the stellar surface.


title:
Linear Mixed Models with Marginally Symmetric Nonparametric Random
  Effects

abstract:
  Linear mixed models (LMMs) are used as an important tool in the data analysis
of repeated measures and longitudinal studies. The most common form of LMMs
utilize a normal distribution to model the random effects. Such assumptions can
often lead to misspecification errors when the random effects are not normal.
One approach to remedy the misspecification errors is to utilize a point-mass
distribution to model the random effects; this is known as the nonparametric
maximum likelihood-fitted (NPML) model. The NPML model is flexible but requires
a large number of parameters to characterize the random-effects distribution.
It is often natural to assume that the random-effects distribution be at least
marginally symmetric. The marginally symmetric NPML (MSNPML) random-effects
model is introduced, which assumes a marginally symmetric point-mass
distribution for the random effects. Under the symmetry assumption, the MSNPML
model utilizes half the number of parameters to characterize the same number of
point masses as the NPML model; thus the model confers an advantage in economy
and parsimony. An EM-type algorithm is presented for the maximum likelihood
(ML) estimation of LMMs with MSNPML random effects; the algorithm is shown to
monotonically increase the log-likelihood and is proven to be convergent to a
stationary point of the log-likelihood function in the case of convergence.
Furthermore, it is shown that the ML estimator is consistent and asymptotically
normal under certain conditions, and the estimation of quantities such as the
random-effects covariance matrix and individual a posteriori expectations is
demonstrated.


title:
The variation of the Randic index with regard to minimum and maximum
  degree

abstract:
  The variation of the Randi\'c index $ R'(G) $ of a graph $G$ is defined by\
$R(G) = \sum_{uv \in E(G)}\frac 1{\max \{d(u) d(v)\}}$, where $d(u)$ is the
degree of vertex $u$ and the summation extends over all edges $uv$ of $G$. Let
$G(k,n)$ be the set of connected simple $n$-vertex graphs with minimum vertex
degree $k$. In this paper we found in $G(k,n)$ graphs for which the variation
of the Randi\'c index attains its minimum value.
  When $k \leq \frac n2$ the extremal graphs are complete split graphs
$K_{k,n-k}^*$, which only vertices of two degrees, i.e. degree $k$ and degree
$n-1$, and the number of vertices of degree $k$ is $n-k$, while the number of
vertices of degree $n-1$ is $k$. For $k \geq \frac n2$ the extremal graphs have
also vertices of two degrees $k$ and $n-1$, and the number of vertices of
degree $k$ is $\frac n2$. Further, we generalized results for graphs with given
maximum degree.


title:
Adaptive TXOP Assignment for QoS Support of Video Traffic in IEEE
  802.11e Networks

abstract:
  Quality of Service (QoS) is provided in IEEE 802.11e protocol by means of HCF
Controlled Channel Access (HCCA) scheduler which is efficient for supporting
Constant Bit Rate (CBR) applications. Numerous researches have been carried out
to enhance the HCCA scheduler attempting to accommodate the needs of Variable
Bit Rate (VBR) video traffics which probably demonstrates a non-deterministic
profile during the time. This paper presents an adaptive TXOP assignment
mechanism for supporting the transmission of the prerecorded video traffics
over IEEE 802.11e wireless networks. The proposed mechanism uses a feedback
about the size of the subsequent video frames of the uplink traffic to assist
the Hybrid Coordinator (HC) accurately assign TXOP according to the fast
changes in the VBR profile. The simulation results show that our mechanism
reduces the delay experienced by VBR traffic streams comparable to HCCA
scheduler due to the accurate assignment of the TXOP which preserve the channel
time for data transmission.


title: Semi-factorial nodal curves and N\'eron models of jacobians

abstract:
  A family of curves over a discrete valuation ring is called semi-factorial if
every line bundle on the generic fibre extends to a line bundle on the total
space. In the nodal case, we give a sufficient and necessary condition for
semi-factoriality, in terms of combinatorics of the dual graph of the special
fibre. In particular, we show that performing one blow-up centered at the
non-regular closed points yields a semi-factorial model of the generic fibre.
  As an application, we extend Raynaud's construction of the N\'eron
(lft)-model of the jacobian of the generic fibre of a family of nodal curves to
the case where the generic fibre is singular.


title:
Simple digital phase-measuring algorithm for low-noise heterodyne
  interferometry

abstract:
  We present a digital algorithm for measuring the phase difference between two
sinusoidal signals that combines the modified fringe-counting method with
two-sample zero crossing to enable sequential signal processing. This technique
can be applied to a phase meter for measuring dynamic phase differences with
high resolution, particularly for heterodyne interferometry. The floor noise
obtained from a demonstration with an electrical apparatus is $5\times10^{-8}
\mathrm{rad/\sqrt{Hz}}$ at frequencies above approximately 0.1 Hz. In addition,
by applying this method to a commercial heterodyne interferometer, the
floor-noise level is confirmed to be $7\times10^{-14} \mathrm{m/\sqrt{Hz}}$
from 4 kHz to 1 MHz. We also confirm the validity of the algorithm by comparing
its results with those from a standard homodyne interferometer for measuring
shock-motion peak acceleration greater than 5000 m/s^2 and a 10 mm stroke.


title: Laser-Driven Multiferroics and Ultrafast Spin Current Generation

abstract:
  We propose an ultrafast way to generate spin chirality and spin current in a
class of multiferroic magnets using a terahertz circularly polarized laser.
Using the Floquet formalism for periodically driven systems, we show that it is
possible to dynamically control the Dzyaloshinskii-Moriya interaction in
materials with magnetoelectric coupling. This is supported by numerical
calculations, by which additional resonant phenomena are found. Specifically,
when a static magnetic field is applied in addition to the circularly polarized
laser, a large resonant enhancement of spin chirality is observed resembling
the electron spin resonance. Spin current is generated when the laser is
spatially modulated by chiral plasmonic structures and could be detected using
optospintronic devices.


title:
High-repetition-rate and high-photon-flux 70 eV high-harmonic source for
  coincidence ion imaging of gas-phase molecules

abstract:
  Unraveling and controlling chemical dynamics requires techniques to image
structural changes of molecules with femtosecond temporal and picometer spatial
resolution. Ultrashort-pulse x-ray free-electron lasers have significantly
advanced the field by enabling advanced pump-probe schemes. There is an
increasing interest in using table-top photon sources enabled by high-harmonic
generation of ultrashort-pulse lasers for such studies. We present a novel
high-harmonic source driven by a 100 kHz fiber laser system, which delivers
10$^{11}$ photons/s in a single 1.3 eV bandwidth harmonic at 68.6 eV. The
combination of record-high photon flux and high repetition rate paves the way
for time-resolved studies of the dissociation dynamics of inner-shell ionized
molecules in a coincidence detection scheme. First coincidence measurements on
CH$_3$I are shown and it is outlined how the anticipated advancement of fiber
laser technology and improved sample delivery will, in the next step, allow
pump-probe studies of ultrafast molecular dynamics with table-top XUV-photon
sources. These table-top sources can provide significantly higher repetition
rates than the currently operating free-electron lasers and they offer very
high temporal resolution due to the intrinsically small timing jitter between
pump and probe pulses.


title: Schr\"odinger-Maxwell systems on Hadamard manifolds

abstract:
  In this paper we study nonlinear Schr\"odinger-Maxwell systems on
$n-$dimensional Hadamard manifolds, $3\leq n\leq 5.$ The main difficulty
resides in the lack of compactness of such manifolds which is recovered by
exploring suitable isometric actions. By combining variational arguments, some
existence, uniqueness and multiplicity of isometry-invariant weak solutions are
established for the Schr\"odinger-Maxwell system depending on the behavior of
the nonlinear term.


title:
Non-Hermitian wave packet approximation for coupled two-level systems in
  weak and intense fields

abstract:
  We introduce an accurate non-Hermitian Schr\"odinger-type approximation of
Bloch optical equations for two-level systems. This approximation provides a
complete description of the excitation, relaxation and decoherence dynamics in
both weak and strong laser fields. In this approach, it is sufficient to
propagate the wave function of the quantum system instead of the density
matrix, providing that relaxation and dephasing are taken into account via
automatically-adjusted time-dependent gain and decay rates. The developed
formalism is applied to the problem of scattering and absorption of
electromagnetic radiation by a thin layer comprised of interacting two-level
emitters.


title: SDxVPN: A Software-Defined Solution for VPN Service Providers

abstract:
  BGP/MPLS IP VPN and VPLS services are considered to be widely used in IP/MPLS
networks for connecting customers' remote sites. However, service providers
struggle with many challenges to provide these services. Management complexity,
equipment costs, and last but not least, scalability issues emerging as the
customers increase in number, are just some of these problems. Software-defined
networking (SDN) is an emerging paradigm that can solve aforementioned issues
using a logically centralized controller for network devices. In this paper, we
propose a SDN-based solution called SDxVPN which considerably lowers the
complexity of VPN service definition and management. Our method eliminates
complex and costly device interactions that used to be done through several
control plane protocols and enables customers to determine their service
specifications, define restriction policies and even interconnect with other
customers automatically without operator's intervention. We describe our
prototype implementation of SDxVPN and its scalability evaluations under
several representative scenarios. The results indicate the effectiveness of the
proposed solution for deployment to provide large scale VPN services.


title: Singular Poisson equations on Finsler-Hadamard manifolds

abstract:
  In the first part of the paper we study the reflexivity of Sobolev spaces on
non-compact and not necessarily reversible Finsler manifolds. Then, by using
direct methods in the calculus of variations, we establish uniqueness, location
and rigidity results for singular Poisson equations involving the
Finsler-Laplace operator on Finsler-Hadamard manifolds having finite
reversibility constant.


title: Quantum gravity and the holographic dark energy cosmology

abstract:
  The holographic dark energy model is obtained from a cosmological constant
generated by generic quantum gravity effects giving a minimum length. By
contrast, the usual bound for the energy density to be limited by the formation
of a black hole simply gives the Friedmann equation. The scale of the current
cosmological constant relative to the inflationary scale is an arbitrary
parameter characterizing initial conditions, which however can be fixed by
introducing a physical principle during inflation, as a function of the number
of e-folds and the inflationary scale.


title: Invariance of the Cuntz splice

abstract: We show that the Cuntz splice induces stably isomorphic graph $C^*$-algebras.


title: Detecting the Collapse of Cooperation in Evolving Networks

abstract:
  The sustainability of structured biological, social, economic and ecological
communities are often determined by the outcome of social conflicts between
cooperative and selfish individuals (cheaters). Cheaters avoid the cost of
contributing to the community and can occasionally spread in the population
leading to the complete collapse of cooperation. Although such a collapse often
unfolds unexpectedly bearing the traits of a critical transition, it is unclear
whether one can detect the rising risk of cheater's invasions and loss of
cooperation in an evolving community. Here, we combine dynamical networks and
evolutionary game theory to study the abrupt loss of cooperation as a critical
transition. We estimate the risk of collapse of cooperation after the
introduction of a single cheater under gradually changing conditions. We
observe a systematic increase in the average time it takes for cheaters to be
eliminated from the community as the risk of collapse increases. We detect this
risk based on changes in community structure and composition. Nonetheless,
reliable detection depends on the mechanism that governs how cheaters evolve in
the community. Our results suggest possible avenues for detecting the loss of
cooperation in evolving communities


title:
Comment on "Insight into the Microscopic Structure of an AdS Black Hole
  from a Thermodynamical Phase Transition"

abstract:
  Thermodynamic geometry analysis of interesting Letter [Phys. Rev. Lett. 115,
111302 (2015)] for charged AdS black holes, which is based on studying the
Ruppeiner invariant behavior is not correct and the authors made a mistake in
calculating this quantity. In the present Letter, we address the correct
Ruppeiner scalar curvature and reveal the correct possible microscopic
properties of 4-dimensional charged AdS black holes arise from it. Some of
these properties have not been discussed in pointed out Letter.


title: Stabilization via Homogenization

abstract:
  In this short note we treat a 1+1-dimensional system of changing type. On
different spatial domains the system is of hyperbolic and elliptic type, that
is, formally, $\partial_t^2 u_n-\partial_x^2 u_n = \partial_t f$ and
$u_n-\partial_x^2 u_n= f$ on the respective spatial domains $\bigcup_{j\in
\{1,\ldots,n\}} \big(\frac{j-1}{n},\frac{2j-1}{2n}\big)$ and $\bigcup_{j\in
\{1,\ldots,n\}} \big(\frac{2j-1}{2n},\frac{j}{n}\big)$. We show that $(u_n)_n$
converges weakly to $u$, which solves the exponentially stable limit equation
$\partial_t^2 u +2\partial_t u + u -4\partial_x^2 u = 2(f+\partial_t f)$ on
$[0,1]$. If the elliptic equation is replaced by a parabolic one, the limit
equation is \emph{not} exponentially stable.


title:
A Distributed $(2+\epsilon)$-Approximation for Vertex Cover in
  $O(\log{\Delta}/\epsilon\log\log{\Delta})$ Rounds

abstract:
  We present a simple deterministic distributed $(2+\epsilon)$-approximation
algorithm for minimum weight vertex cover, which completes in
$O(\log{\Delta}/\epsilon\log\log{\Delta})$ rounds, where $\Delta$ is the
maximum degree in the graph, for any $\epsilon>0$ which is at most $O(1)$. For
a constant $\epsilon$, this implies a constant approximation in
$O(\log{\Delta}/\log\log{\Delta})$ rounds, which contradicts the lower bound of
[KMW10].


title: Characteristics of Cherenkov Radiation in Naturally Occuring Ice

abstract:
  We revisit the theory of Cherenkov radiation in uniaxial crystals.
Historically, a number of flawed attempts have been made at explaining this
radiation phenomenon and a consistent error-free description is nowhere
available. We apply our calculation to a large modern day telescope - IceCube.
Being located at the Antarctica, this detector makes use of the naturally
occuring ice as a medium to generate Cherenkov radiation. However, due to the
high pressure at the depth of the detector site, large volumes of hexagonal ice
crystals are formed. We calculate how this affects the Cherenkov radiation
yield and angular dependence. We conclude that the effect is small, at most
about a percent, and would only be relevant in future high precision
instruments like e.g. Precision IceCube Next Generation Upgrade (PINGU). For
radio-Cherenkov experiments which use the presence of a clear Cherenkov cone to
determine the arrival direction, any variation in emission angle will directly
and linearly translate into a change in apparent neutrino direction. In
closing, we also describe a simple experiment to test this formalism, and
calculate the impact of anisotropy on light-yields from lead tungstate crystals
as used, for example, in the CMS calorimeter at the CERN LHC.


title: A database of genus 2 curves over the rational numbers

abstract:
  We describe the construction of a database of genus 2 curves of small
discriminant that includes geometric and arithmetic invariants of each curve,
its Jacobian, and the associated L-function. This data has been incorporated
into the L-Functions and Modular Forms Database (LMFDB).


title:
Feasible HCCA Polling Mechanism for Video Transmission in IEEE 802.11e
  WLANs

abstract:
  IEEE 802.11e standard defines two Medium Access Control (MAC) functions to
support Quality of Service (QoS) for wireless local area networks: Enhanced
Distributed Channel Access (EDCA) and HCF Controlled Channel Access (HCCA).
EDCA provides fair prioritized QoS support while HCCA guarantees parameterized
QoS for the traffics with rigid QoS requirements. The latter shows higher QoS
provisioning with Constant Bit Rate (CBR) traffics. However, it does not
efficiently cope with the fluctuation of the Variable Bit Rate (VBR) video
streams since its reference scheduler generates a schedule based on the mean
characteristics of the traffic. Scheduling based on theses characteristics is
not always accurate as these tra_cs show high irregularity over the time. In
this paper, we propose an enhancement on the HCCA polling mechanism to address
the problem of scheduling pre-recorded VBR video streams. Our approach enhances
the polling mechanism by feed-backing the arrival time of the subsequent video
frame of the uplink traffic obtained through cross-layering approach.
Simulation experiments have been conducted on several publicly available video
traces in order to show the efficiency of our mechanism. The simulation results
reveal the efficiency of the proposed mechanism in providing less delay and
high throughput with conserving medium channel through minimizing the number of
Null-Frames caused by wasted polls


title:
Plane-wave Density Functional Theory Study of the Electronic and
  Structural Properties of Ionized and Neutral Small Gold Clusters

abstract:
  We studied the structural and the electronic properties of ionized and
neutral small Au clusters via plane wave pseudopotential calculations. All
except the anionic heptamer favor one-dimensional zigzag structures or
two-dimensional arrangements of triangles. The HOMO-LUMO (highest occupied
molecular orbital - lowest unoccupied molecular orbital) gap, the ionization
energy, and the electronic affinity exhibit even-odd variation as a function of
the cluster size.


title: Fast Distributed Algorithms for Testing Graph Properties

abstract:
  We initiate a thorough study of \emph{distributed property testing} --
producing algorithms for the approximation problems of property testing in the
CONGEST model. In particular, for the so-called \emph{dense} testing model we
emulate sequential tests for nearly all graph properties having $1$-sided
tests, while in the \emph{sparse} and \emph{general} models we obtain faster
tests for triangle-freeness and bipartiteness respectively.
  In most cases, aided by parallelism, the distributed algorithms have a much
shorter running time as compared to their counterparts from the sequential
querying model of traditional property testing. The simplest property testing
algorithms allow a relatively smooth transitioning to the distributed model.
For the more complex tasks we develop new machinery that is of independent
interest. This includes a method for distributed maintenance of multiple random
walks.


title:
Discovering novel ingredient pairings in molecular gastronomy using
  network analysis

abstract:
  Molecular gastronomy is a distinct sub-discipline of food science that takes
an active role in examining chemical and physical properties of ingredients and
as such lends itself to more scientific approaches to finding novel ingredient
pairings. With thousands of ingredients and molecules, which participate in the
creation of each ingredient's flavour, it can be difficult to find compatible
flavours in an efficient manner. Existing literature is focused mainly on
analysis of already established cuisine based on the flavour profile of its
ingredients, but fails to consider the potential in finding flavour
compatibility for use in creation of completely new recipes. Expressing
relationships between ingredients and their molecular structure as a bipartite
network opens up this problem to effective analysis with methods from network
science. We describe a series of experiments on a database of food using
network analysis, which produce a set of compatible ingredients that can be
used in creation of new recipes. We expect this approach and its results to
dramatically simplify the creation of new recipes with previously unseen and
fresh combinations of ingredients.


title: Excitons in asymmetric quantum wells

abstract:
  Resonance dielectric response of excitons is studied for the high-quality
GaAs/InGaAs heterostructures with wide asymmetric quantum wells (QWs). To
highlight effects of the QW asymmetry, we have grown and studied several
heterostructures with nominally square QWs as well as with triangle-like QWs.
Several quantum confined exciton states are experimentally observed as narrow
exciton resonances with various profiles. A standard approach for the
phenomenological analysis of the profiles is generalized by introducing of
different phase shifts for the light waves reflected from the QWs at different
exciton resonances. Perfect agreement of the phenomenological fit to the
experimentally observed exciton spectra for high-quality structures allowed us
to obtain reliable parameters of the exciton resonances including the exciton
transition energies, the radiative broadenings, and the phase shifts. A direct
numerical solution of Schr\"{o}dinger equation for the heavy-hole excitons in
asymmetric QWs is used for microscopic modeling of the exciton resonances.
Remarkable agreement with the experiment is achieved when the effect of indium
segregation during the heterostructure growth is taken into account. The
segregation results in a modification of the potential profile, in particular,
in an asymmetry of the nominally square QWs.


title: The $\Lambda_2$ limit of massive gravity

abstract:
  Lorentz-invariant massive gravity is usually associated with a strong
coupling scale $\Lambda_3$. By including non-trivial effects from the
Stueckelberg modes, we show that about these vacua, one can push the strong
coupling scale to higher values and evade the linear vDVZ-discontinuity. For
generic parameters of the theory and generic vacua for the Stueckelberg fields,
the $\Lambda_2$-decoupling limit of the theory is well-behaved and free of any
ghost or gradient-like instabilities. We also discuss the implications for
nonlinear sigma models with Lorentzian target spaces.


title: Sequences with small correlation

abstract:
  The extent to which a sequence of finite length differs from a shifted
version of itself is measured by its aperiodic autocorrelations. Of particular
interest are sequences whose entries are 1 or -1, called binary sequences, and
sequences whose entries are complex numbers of unit magnitude, called
unimodular sequences. Since the 1950s, there is sustained interest in sequences
with small aperiodic autocorrelations relative to the sequence length. One of
the main motivations is that a sequence with small aperiodic autocorrelations
is intrinsically suited for the separation of signals from noise, and therefore
has natural applications in digital communications. This survey reviews the
state of knowledge concerning the two central problems in this area: How small
can the aperiodic autocorrelations of a binary or a unimodular sequence
collectively be and how can we efficiently find the best such sequences? Since
the analysis and construction of sequences with small aperiodic
autocorrelations is closely tied to the (often much easier) analysis of
periodic autocorrelation properties, several fundamental results on
corresponding problems in the periodic setting are also reviewed.


title: Density-Matrix Propagation Driven by Semiclassical Correlation

abstract:
  Methods based on propagation of the one-body reduced density-matrix hold much
promise for the simulation of correlated many-electron dynamics far from
equilibrium, but difficulties with finding good approximations for the
interaction term in its equation of motion have so far impeded their
application. These difficulties include the violation of fundamental physical
principles such as energy conservation, positivity conditions on the density,
or unchanging natural orbital occupation numbers. We review some of the recent
efforts to confront these problems, and explore a semiclassical approximation
for electron correlation coupled to time-dependent Hartree-Fock propagation. We
find that this approach captures changing occupation numbers, and excitations
to doubly-excited states, improving over TDHF and adiabatic approximations in
density-matrix propagation. However, it does not guarantee $N$-representability
of the density-matrix, consequently resulting sometimes in violation of
positivity conditions, even though a purely semiclassical treatment preserves
these conditions.


title: Role of electronic shell in the double beta decay

abstract:
  We demonstrate that the limiting energy available for ejected electrons in
double beta decay is diminished by about 400 eV due to inelastic processes in
the electronic shell.


title:
A Versatile Scene Model with Differentiable Visibility Applied to
  Generative Pose Estimation

abstract:
  Generative reconstruction methods compute the 3D configuration (such as pose
and/or geometry) of a shape by optimizing the overlap of the projected 3D shape
model with images. Proper handling of occlusions is a big challenge, since the
visibility function that indicates if a surface point is seen from a camera can
often not be formulated in closed form, and is in general discrete and
non-differentiable at occlusion boundaries. We present a new scene
representation that enables an analytically differentiable closed-form
formulation of surface visibility. In contrast to previous methods, this yields
smooth, analytically differentiable, and efficient to optimize pose similarity
energies with rigorous occlusion handling, fewer local minima, and
experimentally verified improved convergence of numerical optimization. The
underlying idea is a new image formation model that represents opaque objects
by a translucent medium with a smooth Gaussian density distribution which turns
visibility into a smooth phenomenon. We demonstrate the advantages of our
versatile scene model in several generative pose estimation problems, namely
marker-less multi-object pose estimation, marker-less human motion capture with
few cameras, and image-based 3D geometry estimation.


title:
Gaussian fluctuations in the two-dimensional BCS-BEC crossover: finite
  temperature properties

abstract:
  The role of fluctuations is enhanced in lower dimensionality systems: in a
two dimensions off-diagonal long-range order is destroyed by the fluctuations
at any finite temperature, drastically modifying the critical properties with
respect to the three-dimensional counterpart. Recently two-dimensional systems
of interacting fermions have been the subject of Montecarlo studies and
experimental investigations, in particular an ultracold gas of attractive
fermions with a widely tunable interaction due to a Feshbach resonance has been
realized and the Berezinskii-Kosterlitz-Thouless transition has been observed.
  The present work deals with the theoretical description of an ultracold Fermi
gas: we discuss the role of Gaussian fluctuations of the order parameter in the
equation of state, in particular we take into account the first sound velocity,
showing that the inclusion of order parameter fluctuations is needed in order
to get the correct composite-boson limit in the strong-coupling regime. The
theory is also compared with experimental data. Finally we focus on the
superfluid density in the weak-coupling, intermediate and strong-coupling
regimes at finite temperature, through which the
Berezinskii-Kosterlitz-Thouless critical temperature is obtained.


title: Resampling-based inference methods for comparing two coefficient alpha

abstract:
  The two-sample problem for Cronbach's coefficient $\alpha_C$, as an estimate
of test or composite score reliability, has attracted little attention,
compared to the extensive treatment of the one-sample case. It is necessary to
compare the reliability of a test for different subgroups, for different tests
or the short and long forms of a test. In this paper, we study statistically
how to compare two coefficients $\alpha_{C,1}$ and $\alpha_{C,2}$. The null
hypothesis of interest is $H_0 : \alpha_{C,1} = \alpha_{C,2}$, which we test
against one-or two-sided alternatives. For this purpose, resampling-based
permutation and bootstrap tests are proposed. These statistical tests ensure a
better control of the type I error, in finite or very small sample sizes, when
the state-of-affairs \textit{asymptotically distribution-free} (ADF)
large-sample test may fail to properly attain the nominal significance level.
We introduce the permutation and bootstrap tests for the two-group multivariate
non-normal models under the general ADF setting, thereby improving on the small
sample properties of the well-known ADF asymptotic test. By proper choice of a
studentized test statistic, the resampling tests are modified such that they
are still asymptotically valid, if the data may not be exchangeable. The
usefulness of the proposed resampling-based testing strategies is demonstrated
in an extensive simulation study and illustrated by real data applications.


title: Logarithmic form of Lagrange inversion formula

abstract:
  We give presentation of composition inverse of formal power serie in a
logarithmic form.


title: A Language for the Declarative Composition of Concurrent Protocols

abstract:
  A recent study of bugs in real-world concurrent and distributed systems found
that, while implementations of individual protocols tend to be robust, the
composition of multiple protocols and its interplay with internal computation
is the culprit for most errors. Multiparty Session Types and Choreographic
Programming are methodologies for developing correct-by-construction concurrent
and distributed software, based on global descriptions of communication flows.
However, protocol composition is either limited or left unchecked. Inspired by
these two methodologies, in this work we present a new language model for the
safe composition of protocols, called Procedural Choreographies (PC). Protocols
in PC are procedures, parameterised on the processes that enact them.
Procedures define communications declaratively using global descriptions, and
programs are written by invoking and composing these procedures. An
implementation in terms of a process model is then mechanically synthesised,
guaranteeing correctness and deadlock-freedom. We study PC in the settings of
synchronous and asynchronous communications, and illustrate its expressivity
with some representative examples.


title: HDBSCAN: Density based Clustering over Location Based Services

abstract:
  Location Based Services (LBS) have become extremely popular and used by
millions of users. Popular LBS run the entire gamut from mapping services (such
as Google Maps) to restaurants (such as Yelp) and real-estate (such as Redfin).
The public query interfaces of LBS can be abstractly modeled as a kNN interface
over a database of two dimensional points: given an arbitrary query point, the
system returns the k points in the database that are nearest to the query
point. Often, k is set to a small value such as 20 or 50. In this paper, we
consider the novel problem of enabling density based clustering over an LBS
with only a limited, kNN query interface. Due to the query rate limits imposed
by LBS, even retrieving every tuple once is infeasible. Hence, we seek to
construct a cluster assignment function f(.) by issuing a small number of kNN
queries, such that for any given tuple t in the database which may or may not
have been accessed, f(.) outputs the cluster assignment of t with high
accuracy. We conduct a comprehensive set of experiments over benchmark datasets
and popular real-world LBS such as Yahoo! Flickr, Zillow, Redfin and Google
Maps.


title: Quantum Correlations and Coherence in Spin-1 Heisenberg Chains

abstract:
  We explore quantum and classical correlations along with coherence in the
ground states of spin-1 Heisenberg chains, namely the one-dimensional XXZ model
and the one-dimensional bilinear biquadratic model, with the techniques of
density matrix renormalization group theory. Exploiting the tools of quantum
information theory, that is, by studying quantum discord, quantum mutual
information and three recently introduced coherence measures in the reduced
density matrix of two nearest neighbor spins in the bulk, we investigate the
quantum phase transitions and special symmetry points in these models. We point
out the relative strengths and weaknesses of correlation and coherence measures
as figures of merit to witness the quantum phase transitions and symmetry
points in the considered spin-1 Heisenberg chains. In particular, we
demonstrate that as none of the studied measures can detect the infinite order
Kosterlitz-Thouless transition in the XXZ model, they appear to be able to
signal the existence of the same type of transition in the biliear biquadratic
model. However, we argue that what is actually detected by the measures here is
the SU(3) symmetry point of the model rather than the infinite order quantum
phase transition. Moreover, we show in the XXZ model that examining even single
site coherence can be sufficient to spotlight the second-order phase transition
and the SU(2) symmetry point.


title:
The alternating group of degree 5 and the icosahedron rotations: seeing
  not only proving

abstract:
  When compared with pure mathematicians, applied ones have a clear preference
for proofs that go beyond a chain of reasonings and do exhibit the fact to be
proved. Here we exhibit the bijection between the 60 icosahedron rotations of
the group R and the 60 permutations of the group A5.


title: Knot mosaic tabulation

abstract:
  In 2008, Lomonaco and Kauffman introduced a knot mosaic system to define a
quantum knot system. A quantum knot is used to describe a physical quantum
system such as the topology or status of vortexing that occurs on a small scale
can not see. Kuriya and Shehab proved that knot mosaic type is a complete
invariant of tame knots. In this article, we consider the mosaic number of a
knot which is a natural and fundamental knot invariant defined in the knot
mosaic system. We determine the mosaic number for all eight-crossing or fewer
prime knots. This work is written at an introductory level to encourage other
undergraduates to understand and explore this topic. No prior of knot theory is
assumed or required.


title: Strongly Near Voronoi Nucleus Clusters

abstract:
  This paper introduces nucleus clustering in Voronoi tessellations of plane
surfaces with applications in the geometry of digital images. A \emph{nucleus
cluster} is a collection of Voronoi regions that are adjacent to a Voronoi
region called the cluster nucleus. Nucleus clustering is a carried out in a
strong proximity space. Of particular interest is the presence of maximal
nucleus clusters in a tessellation. Among all of the possible nucleus clusters
in a Voronoi tessellation, clusters with the highest number of adjacent
polygons are called \emph{maximal nucleus clusters}. The main results in this
paper are that strongly near nucleus clusters are strongly descriptively near
and every collection of Voronoi regions in a tessellation of a plane surface is
a Zelins'kyi-Soltan-Kay-Womble convexity structure.


title: Coloring Sums of Extensions of Certain Graphs

abstract:
  Recall that the minimum number of colors that allow a proper coloring of
graph $G$ is called the chromatic number of $G$ and denoted by $\chi(G).$ In
this paper the concepts of $\chi$'-chromatic sum and $\chi^+$-chromatic sum are
introduced. The extended graph $G^x$ of a graph $G$ was recently introduced for
certain regular graphs. We further the concepts of $\chi$'-chromatic sum and
$\chi^+$-chromatic sum to extended paths and cycles. The paper concludes with
\emph{patterned structured} graphs.


title: Extending Sicherman Dice to 100-cell Calculation Tables

abstract:
  This paper discusses a 100-cell calculation table for addition,
C(i,j)=Ai+Bj,(1<=i,j<=10), addressing the special case where the 100 cells
C(i,j) comprise continuous numbers 0 through 99. We consider what sequences
{Ai,Bj,(1<=i,j<=10)} are needed to fulfill these conditions, and the number of
possible combinations. We first find seven solutions through factorization of
the generating function used for Sicherman dice. We next find seven solutions
through geometric means. We demonstrate a correspondence between the seven
solutions from factorization and the seven from geometry. Finally, we suggest
that the number of solutions N for an nxn=n^2-cell calculation table is
N=(p-2)(p-1)+1, where p is the number of divisors of n.


title:
On the precision of a data-driven estimate of the pseudoscalar-pole
  contribution to hadronic light-by-light scattering in the muon g-2

abstract:
  The evaluation of the numerically dominant pseudoscalar-pole contribution to
hadronic light-by-light scattering in the muon g-2 involves the
pseudoscalar-photon transition form factor F_{P gamma^* gamma^*}(-Q_1^2,
-Q_2^2) with P = pi^0, eta, eta^\prime and, in general, two off-shell photons
with spacelike momenta Q_{1,2}^2. We determine which regions of photon momenta
give the main contribution for hadronic light-by-light scattering. Furthermore,
we analyze how the precision of future measurements of the single- and
double-virtual form factor impacts the precision of a data-driven estimate of
this contribution to hadronic light-by-light scattering.


title: Field Driven Charging Dynamics of a Fluidized Granular Bed

abstract:
  A simplified model has previously described the inductive charging of
colliding identical grains in the presence of an external electric field. Here
we extend that model by including heterogeneous surface charge distributions,
grain rotations and electrostatic interactions between grains. We find from
this more realistic model that strong heterogeneities in charging can occur in
agitated granular beds, and we predict that shielding due to these
heterogeneities can dramatically alter the charging rate in such beds.


title:
Qualities and Inequalities in Online Social Networks through the Lens of
  the Generalized Friendship Paradox

abstract:
  The friendship paradox is the phenomenon that in social networks, people on
average have fewer friends than their friends do. The generalized friendship
paradox is an extension to attributes other than the number of friends. The
friendship paradox and its generalized version have gathered recent attention
due to the information they provide about network structure and local
inequalities. In this paper, we propose several measures of nodal qualities
which capture different aspects of their activities and influence in online
social networks. Using these measures we analyse the prevalence of the
generalized friendship paradox over Twitter and we report high levels of
prevalence (up to over 90\% of nodes). We contend that this prevalence of the
friendship paradox and its generalized version arise because of the
hierarchical nature of the connections in the network. This hierarchy is nested
as opposed to being star-like. We conclude that these paradoxes are collective
phenomena not created merely by a minority of well-connected or high-attribute
nodes. Moreover, our results show that a large fraction of individuals can
experience the generalized friendship paradox even in the absence of a
significant correlation between degrees and attributes.


title:
Calculation of Energy Spectrum of 12C Isotope by Relativistic Cluster
  model

abstract:
  In this paper, we have calculated the energy spectrum of 12C isotope by
cluster model. The experimental results show that the "Hoyle" state at 7.65 MeV
in 12C isotope has a well-developed three-alpha structure. Hence, we select a
three-body system and for interaction between the clusters we use modified
Yukawa potential plus coulomb potential. Then, we solve the relativistic
Klein-Gordon equation using Nikiforov-Uvarov method to calculate the energy
spectrum. Finally, the calculated results are compared with the experimental
data. The results show that the isotope 12C should be considered as consisting
of three-alpha cluster and the modified Yukawa potential is adaptable for
cluster interactions.


title: The List Distinguishing Number of Kneser Graphs

abstract:
  A graph $G$ is said to be $k$-distinguishable if the vertex set can be
colored using $k$ colors such that no non-trivial automorphism fixes every
color class, and the distinguishing number $D(G)$ is the least integer $k$ for
which $G$ is $k$-distinguishable. If for each $v\in V(G)$ we have a list $L(v)$
of colors, and we stipulate that the color assigned to vertex $v$ comes from
its list $L(v)$ then $G$ is said to be $\mathcal{L}$-distinguishable where
$\mathcal{L} =\{L(v)\}_{v\in V(G)}$. The list distinguishing number of a graph,
denoted $D_l(G)$, is the minimum integer $k$ such that every collection of
lists $\mathcal{L}$ with $|L(v)|=k$ admits an $\mathcal{L}$-distinguishing
coloring. In this paper, we prove that $D_l(G)=D(G)$ when $G$ is a Kneser
graph.


title: HMM and DTW for evaluation of therapeutical gestures using kinect

abstract:
  Automatic recognition of the quality of movement in human beings is a
challenging task, given the difficulty both in defining the constraints that
make a movement correct, and the difficulty in using noisy data to determine if
these constraints were satisfied. This paper presents a method for the
detection of deviations from the correct form in movements from physical
therapy routines based on Hidden Markov Models, which is compared to Dynamic
Time Warping. The activities studied include upper an lower limbs movements,
the data used comes from a Kinect sensor. Correct repetitions of the activities
of interest were recorded, as well as deviations from these correct forms. The
ability of the proposed approach to detect these deviations was studied.
Results show that a system based on HMM is much more likely to determine if a
certain movement has deviated from the specification.


title: On possible tachyonic state of neutrino dark matter

abstract:
  We revive the historically first dark matter model based on neutrinos, but
with an additional assumption that neutrinos might exist in tachyonic almost
sterile states. To this end, we propose a group-theoretical algorithm for the
description of tachyons. The key point is that we employ a distinct tachyon
Lorentz group with new (superluminal) parametrization which does not lead to
violation of causality and unitarity. Our dark matter model represents
effectively scalar tachyonic neutrino-antineutrino conglomerate. Distributed
all over the universe, such fluid behaves as stable isothermal/stiff medium
which produces somewhat denser regions (`halos') around galaxies and clusters.
To avoid the central singularity inherent to the isothermal profile, we apply a
special smoothing algorithm which yields density distributions and rotation
curves consistent with observational data.


title: The question of charge and of mass

abstract:
  There are two long-range forces in the Universe, electromagnetism and
gravity.We have found a general expression for the energy of interaction in
these cases alphaXhbarXc/r, where alpha is the fine structure constant and r is
the distance between the two particles.In the case of the electromagnetic
interaction we have alphaxhbarxc=e^2/4pixepsilon, where e is the gauge charge,
which is the elementary electron charge. In the case of the gravitational
interaction alphaxhbarxc=GxM^2where M=1.85x10^(-9) kg is the gauge mass of the
particle.This is a giant particle. A system of like charged giant particles,
would be a charged superfluid. By spontaneous breaking of a gauge symmetry are
generated the Higgs masive bosons.The unitary gauge assure generation of the
neutral massive particles. The perturbation from the unitary gauge generates
charged massive particles. Also, the Higgs boson decays into charged and
neutral particles.The Tesla coil is the user of the excitations of the vacuum.


title: Spinon dynamics in quantum integrable antiferromagnets

abstract:
  The excitations of the Heisenberg antiferromagnetic spin chain in zero field
are known as spinons. As pairwise-created fractionalized excitations, spinons
are important in the understanding of inelastic neutron scattering experiments
in (quasi) one-dimensional materials. In the present work, we consider the real
space-time dynamics of spinons originating from a local spin flip on the
antiferromagnetic ground state of the (an)isotropic Heisenberg spin-1/2 model
and the Babujan-Takhtajan spin-1 model. By utilizing algebraic Bethe ansatz
methods at finite system size to compute the expectation value of the local
magnetization and spin-spin correlations, spinons are visualized as propagating
domain walls in the antiferromagnetic spin ordering with anisotropy dependent
behavior. The spin-spin correlation after the spin flip displays a light cone,
satisfying the Lieb-Robinson bound for the propagation of correlations at the
spinon velocity.


title: Finding overlapping communities in multiplex networks

abstract:
  We define an approach to identify overlapping communities in multiplex
networks, extending the popular clique percolation method for simple graphs.
The extension requires to rethink the basic concepts on which the clique
percolation algorithm is based, including cliques and clique adjacency, to
allow the presence of multiple types of edges.


title:
New class of sequences of fuzzy numbers defined by modulus function and
  generalized weighted mean

abstract:
  In this paper, We have introduced a new class of sequences of fuzzy numbers
defined by using modulus function and generalized weighted mean over the class
defined in \cite{OS}. We have proved that this class form a quasilinear
complete metric space under a suitable metric. Various inclusion relations and
some properties such as solidness, symmetry are investigated.


title:
Momentum structure of the self-energy and its parametrization for the
  two-dimensional Hubbard model

abstract:
  We compute the self-energy for the half-filled Hubbard model on a square
lattice using lattice quantum Monte Carlo simulations and the dynamical vertex
approximation. The self-energy is strongly momentum dependent, but it can be
parametrized via the non-interacting energy-momentum dispersion
$\varepsilon_{\mathbf{k}}$, except for pseudogap features right at the Fermi
edge. That is, it can be written as $\Sigma(\varepsilon_{\mathbf{k}},\omega)$,
with two energy-like parameters ($\varepsilon$, $\omega$) instead of three
($k_x$, $k_y$ and $\omega$). The self-energy has two rather broad and weakly
dispersing high energy features and a sharp $\omega= \varepsilon_{\mathbf{k}}$
feature at high temperatures, which turns to $\omega=
-\varepsilon_{\mathbf{k}}$ at low temperatures. Altogether this yields a Z- and
reversed-Z-like structure, respectively, for the imaginary part of
$\Sigma(\varepsilon_{\mathbf{k}},\omega)$. We attribute the change of the low
energy structure to antiferromagnetic spin fluctuations.


title:
Clinical Validation of two Surface Imaging Systems for Patient
  Positioning in Percutaneous Radiotherapy

abstract:
  Precise patient positioning and thus precise positioning of the planning
target volume (PTV) is a prerequisite for effective treatment in percutaneous
radiation therapy. Conventional imaging modalities used to ensure exact
positioning for treatment typically involve additional radiation exposure of
the patient. A different approach to patient alignment without additional
exposure is provided by optical 3D surface scanning and registration systems.
  We investigated two systems Catalyst and AlignRT, which allowed us to
generate and validate surface images of 50 patients undergoing irradiation on a
Tomotherapy system. We compared the positions proposed by these two surface
imaging systems (SIS) with the actual adjustments in patient positions made on
the basis of MVCT scans. With the two SIS, the surface of every single patient
was repeatedly recorded throughout treatment. In addition, we performed a
systematic analysis of both systems using a body phantom.
  At least 10 surface images were available from each patient included in the
analysis. The large number of patients allowed us to subdivide the study
population into three groups by body region treated: head & neck, chest, and
pelvic. The results for each of these three body regions were separately
analyzed. Thus, the focus of our investigation is on body regions registered
with the two systems rather than tumor entities. For AlignRT, for instance, we
found an improvement in positioning for the Pelvic region of 0.9mm in 75% and
6.4mm in 95% of the collected data in comparison to conventional marker
alignment.
  The two systems were most accurate in the head & neck region, where
conventional mask alignment is already sufficiently accurate. The other two
body regions, pelvic and chest, might benefit from positioning by SIS. But for
both systems there is still a need for improvement to reduce statistical
variation.


title: Symmetry operators of Killing spinors and superalgebras in AdS_5

abstract:
  We construct the first-order symmetry operators of Killing spinor equation in
terms of odd Killing-Yano forms. By modifying the Schouten-Nijenhuis bracket of
Killing-Yano forms, we show that the symmetry operators of Killing spinors
close into an algebra in AdS_5 spacetime. Since the symmetry operator algebra
of Killing spinors corresponds to a Jacobi identity in extended Killing
superalgebras, we investigate the possible extensions of Killing superalgebras
to include higher-degree Killing-Yano forms. We found that there is a
superalgebra extension but no Lie superalgebra extension of the Killing
superalgebra constructed out of Killing spinors and odd Killing-Yano forms in
AdS_5 background.


title:
Basin stability approach for quantifying responses of multistable
  systems with parameters mismatch

abstract:
  In this paper we propose a new method to detect and classify coexisting
solutions in nonlinear systems. We focus on mechanical and structural systems
where we usually avoid multistability for safety and reliability. We want to be
sure that in the given range of parameters and initial conditions the expected
solution is the only possible or at least has dominant basin of attraction. We
propose an algorithm to estimate the probability of reaching the solution in
given (accessible) ranges of initial conditions and parameters. We use a
modified method of basin stability (Menck et. al., Nature Physics, 9(2) 2013).
In our investigation we examine three different systems: a Duffing oscillator
with a tuned mass absorber, a bilinear impacting oscillator and a beam with
attached rotating pendula. We present the results that prove the usefulness of
the proposed algorithm and highlight its strengths in comparison with classical
analysis of nonlinear systems (analytical solutions, path-following, basin of
attraction ect.). We show that with relatively small computational effort
(comparing to classical analysis) we can predict the behaviour of the system
and select the ranges in parameter's space where the system behaves in a
presumed way. The method can be used in all types of nonlinear complex systems.