title:
Echo State Networks for Proactive Caching in Cloud-Based Radio Access
  Networks with Mobile Users

abstract:
  In this paper, the problem of proactive caching is studied for cloud radio
access networks (CRANs). In the studied model, the baseband units (BBUs) can
predict the content request distribution and mobility pattern of each user,
determine which content to cache at remote radio heads and BBUs. This problem
is formulated as an optimization problem which jointly incorporates backhaul
and fronthaul loads and content caching. To solve this problem, an algorithm
that combines the machine learning framework of echo state networks with
sublinear algorithms is proposed. Using echo state networks (ESNs), the BBUs
can predict each user's content request distribution and mobility pattern while
having only limited information on the network's and user's state. In order to
predict each user's periodic mobility pattern with minimal complexity, the
memory capacity of the corresponding ESN is derived for a periodic input. This
memory capacity is shown to be able to record the maximum amount of user
information for the proposed ESN model. Then, a sublinear algorithm is proposed
to determine which content to cache while using limited content request
distribution samples. Simulation results using real data from Youku and the
Beijing University of Posts and Telecommunications show that the proposed
approach yields significant gains, in terms of sum effective capacity, that
reach up to 27.8% and 30.7%, respectively, compared to random caching with
clustering and random caching without clustering algorithm.


title:
WASP-92b, WASP-93b and WASP-118b: Three new transiting close-in giant
  planets

abstract:
  We present the discovery of three new transiting giant planets, first
detected with the WASP telescopes, and establish their planetary nature with
follow up spectroscopy and ground-based photometric lightcurves. WASP-92 is an
F7 star, with a moderately inflated planet orbiting with a period of 2.17 days,
which has $R_p = 1.461 \pm 0.077 R_{\rm J}$ and $M_p = 0.805 \pm 0.068 M_{\rm
J}$. WASP-93b orbits its F4 host star every 2.73 days and has $R_p = 1.597 \pm
0.077 R_{\rm J}$ and $M_p = 1.47 \pm 0.029 M_{\rm J}$. WASP-118b also has a hot
host star (F6) and is moderately inflated, where $R_p = 1.440 \pm 0.036 R_{\rm
J}$ and $M_p = 0.513 \pm 0.041 M_{\rm J}$ and the planet has an orbital period
of 4.05 days. They are bright targets (V = 13.18, 10.97 and 11.07 respectively)
ideal for further characterisation work, particularly WASP-118b, which is being
observed by K2 as part of campaign 8. WASP-93b is expected to be tidally
migrating outwards, which is divergent from the tidal behaviour of the majority
of hot Jupiters discovered.


title:
The Magnetic Part of the Weyl Tensor, and the Expansion of Discrete
  Universes

abstract:
  We examine the effect that the magnetic part of the Weyl tensor has on the
large-scale expansion of space. This is done within the context of a class of
cosmological models that contain regularly arranged discrete masses, rather
than a continuous perfect fluid. The natural set of geodesic curves that one
should use to consider the cosmological expansion of these models requires the
existence of a non-zero magnetic part of the Weyl tensor. We include this
object in the evolution equations of these models by performing a Taylor series
expansion about a hypersurface where it initially vanishes. At the same
cosmological time, measured as a fraction of the age of the universe, we find
that the influence of the magnetic part of the Weyl tensor increases as the
number of masses in the universe is increased. We also find that the influence
of the magnetic part of the Weyl tensor increases with time, relative to the
leading-order electric part, so that its contribution to the scale of the
universe can reach values of ~1%, before the Taylor series approximation starts
to break down.


title:
Theoretical benchmarking of laser-accelerated ion fluxes by 2D-PIC
  simulations

abstract:
  There currently exists a number of different schemes for laser based ion
acceleration in the literature. Some of these schemes are also partly
overlapping, making a clear distinction between the schemes difficult in
certain parameter regimes. Here, we provide a systematic numerical comparison
between the following schemes and their analytical models: light-sail
acceleration, Coulomb explosions, hole boring acceleration, and target normal
sheath acceleration (TNSA). We study realistic laser parameters and various
different target designs, each optimized for one of the acceleration schemes,
respectively. As a means of comparing the schemes, we compute the ion current
density generated at different laser powers, using two-dimensional
particle-in-cell (PIC) simulations, and benchmark the particular analytical
models for the corresponding schemes against the numerical results. Finally, we
discuss the consequences for attaining high fluxes through the studied laser
ion-acceleration schemes.


title: Relativistic Rotating Vector Model

abstract:
  The direction of polarization produced by a moving source rotates with the
respect to the rest frame. We show that this effect, induced by pulsar
rotation, leads to an important correction to polarization swings within the
framework of rotating vector model (RVM); this effect has been missed by
previous works. We construct relativistic RVM taking into account finite
heights of the emission region that lead to aberration, time-of-travel effects
and relativistic rotation of polarization. Polarizations swings at different
frequencies can be used, within the assumption of the radius-to-frequency
mapping, to infer emission radii and geometry of pulsars.


title:
Molecular predissociation resonances near an energy-level crossing II:
  Vector field interaction

abstract:
  We study the resonances of a two-by-two semiclassical system of one
dimensional Schr\"odinger operators, near an energy where the two potentials
intersect transversally, one of them being bonding, and the other one
anti-bonding. Assuming that the interaction is a vector-field, we obtain
optimal estimates on the location and on the widths of these resonances.


title: On frequency and time domain models of traveling wave tubes

abstract:
  We discuss the envelope modulation assumption of frequency-domain models of
traveling wave tubes (TWTs) and test its consistency with the Maxwell
equations. We compare the predictions of usual frequency-domain models with
those of a new time domain model of the TWT.


title:
Normalization in Banach scale Lie algebras via mould calculus and
  applications

abstract:
  We study a perturbative scheme for normalization problems involving
resonances of the unperturbed situation, and therefore the necessity of a
non-trivial normal form, in the general framework of Banach scale Lie algebras
(this notion is defined in the article). This situation covers the case of
classical and quantum normal forms in a unified way which allows a direct
comparison. In particular we prove a precise estimate for the difference
between quantum and classical normal forms, proven to be of order of the square
of the Planck constant. Our method uses mould calculus (recalled in the
article) and properties of the solution of a universal mould equation studied
in a preceding paper.

categories: math.AP math-ph math.DS math.MP quant-ph


title: Weighted Multilevel Langevin Simulation of Invariant Measures

abstract:
  We investigate a weighted Multilevel Richardson-Romberg extrapolation for the
ergodic approximation of invariant distributions of diffusions adapted from the
one introduced in~[Lemaire-Pag\`es, 2013] for regular Monte Carlo simulation.
In a first result, we prove under weak confluence assumptions on the diffusion,
that for any integer $R\ge2$, the procedure allows us to attain a rate
$n^{\frac{R}{2R+1}}$ whereas the original algorithm convergence is at a weak
rate $n^{1/3}$. Furthermore, this is achieved without any explosion of the
asymptotic variance. In a second part, under stronger confluence assumptions
and with the help of some second order expansions of the asymptotic error, we
go deeper in the study by optimizing the choice of the parameters involved by
the method. In particular, for a given $\varepsilon\textgreater{}0$, we exhibit
some semi-explicit parameters for which the number of iterations of the Euler
scheme required to attain a Mean-Squared Error lower than $\varepsilon^2$ is
about $\varepsilon^{-2}\log(\varepsilon^{-1})$. Finally, we numerically this
Multilevel Langevin estimator on several examples including the simple
one-dimensional Ornstein-Uhlenbeck process but also on a high dimensional
diffusion motivated by a statistical problem. These examples confirm the
theoretical efficiency of the method.


title:
Privacy-driven Access Control in Social Networks by Means of Automatic
  Semantic Annotation

abstract:
  In online social networks (OSN), users quite usually disclose sensitive
information about themselves by publishing messages. At the same time, they are
(in many cases) unable to properly manage the access to this sensitive
information due to the following issues: i) the rigidness of the access control
mechanism implemented by the OSN, and ii) many users lack of technical
knowledge about data privacy and access control. To tackle these limitations,
in this paper, we propose a dynamic, transparent and privacy-driven access
control mechanism for textual messages published in OSNs. The notion of
privacy-driven is achieved by analyzing the semantics of the messages to be
published and, according to that, assessing the degree of sensitiveness of
their contents. For this purpose, the proposed system relies on an automatic
semantic annotation mechanism that, by using knowledge bases and linguistic
tools, is able to associate a meaning to the information to be published. By
means of this annotation, our mechanism automatically detects the information
that is sensitive according to the privacy requirements of the publisher of
data, with regard to the type of reader that may access such data. Finally, our
access control mechanism automatically creates sanitized versions of the users'
publications according to the type of reader that accesses them. As a result,
our proposal, which can be integrated in already existing social networks,
provides an automatic, seamless and content-driven protection of user
publications, which are coherent with her privacy requirements and the type of
readers that access them. Complementary to the system design, we also discuss
the feasibility of the system by illustrating it through a real example and
evaluate its accuracy and effectiveness over standard approaches.


title:
Observations of gravity wave forcing of themesopause region during the
  January 2013 major Sudden Stratospheric Warming

abstract:
  Studies of vertical and interhemispheric coupling during Sudden Stratospheric
Warmings (SSWs) suggest that gravity wave (GW) momentum flux divergence plays a
key role in forcing the middle atmosphere, although observational validation of
GW forcing is limited. We present a whole atmosphere view of zonal winds from
the surface to 100 km during the January 2013 major SSW, together with observed
GW momentum fluxes in the mesopause region derived from uninterrupted
high-resolution meteor radar observations from an All-Sky Interferometric
Meteor Radar system located at Trondheim, Norway (63.4 $^{\circ}$N, 10.5
$^{\circ}$E). Observations show GW momentum flux divergence 6 days prior to the
SSW onset, producing an eastward forcing with peak values of $\sim$+145 $\pm$
60m $s^{-1}$ $d^{-1}$. As the SSW evolves, GW forcing turns westward, reaching
a minimum of $\sim$-240 $\pm$ 70 m $s^{-1}$ $d^{-1}$ $\sim$+18 days after the
SSW onset. These results are discussed in light of previous studies and
simulations using the Whole Atmosphere Community Climate Model with Specified
Dynamics.


title:
Landau level splittings, phase transitions, and non-uniform charge
  distribution in trilayer graphene

abstract:
  We report on magneto-transport studies of dual-gated, Bernal-stacked trilayer
graphene (TLG) encapsulated in boron nitride crystals. We observe a quantum
Hall effect staircase which indicates a complete lifting of the twelve-fold
degeneracy of the zeroth Landau level. As a function of perpendicular electric
field, our data exhibits a sequence of phase transitions between all integer
quantum Hall states in the filling factor interval $-8<\nu<0$. We develop a
theoretical model and argue that, in contrast to monolayer and bilayer
graphene, the observed Landau level splittings and quantum Hall phase
transitions can be understood within a single-particle picture, but imply the
presence of a charge density imbalance between the inner and outer layers of
TLG, even at charge neutrality and zero transverse electric field. Our results
indicate the importance of a previously unaccounted band structure parameter
which, together with a more accurate estimate of the other tight-binding
parameters, results in a significantly improved determination of the electronic
and Landau level structure of TLG.


title: A weak Harnack estimate for supersolutions to the porous medium equation

abstract:
  In this work, we prove a weak Harnack estimate for the weak supersolutions to
the porous medium equation. The proof is based on a priori estimates for the
supersolutions and measure theoretical arguments.


title: Exclusive Photoproduction of Upsilon in pPb collisions with the CMS

abstract:
  Results of exclusive photoproduction of Upsilon states in Ultraperipheral
collisions (UPC) of protons and ions with the CMS experiment are presented,
which provides a clean probe of the gluon distribution at small values of
parton fractional momenta $x \approx 10^{-2} 10^{4}$ at central rapidities (|y|
$< 2.5$). The three Upsilon states (1S, 2S, 3S) are measured in the dimuon
decay channel along with the photon-photon decaying to dimuon QED continuum at
$\sqrt{s_{NN}}=5.02$~TeV for integrated luminosity of $L_{int} = 35$ nb$^{-1}$.
The total Upsilon photoproduction cross sections at different photon-proton
center of mass energy $W_{\gamma p}$ and t-differential distributions are
presented and compared with other experimental results as well as theoretical
predictions.


title:
Characterizing the Youngest Herschel-detected Protostars II. Molecular
  Outflows from the Millimeter and the Far-infrared

abstract:
  We present CARMA CO (J=1-0) observations and Herschel PACS spectroscopy,
characterizing the outflow properties toward extremely young and deeply
embedded protostars in the Orion molecular clouds. The sample comprises a
subset of the Orion protostars known as the PACS Bright Red Sources (PBRS)
(Stutz et al. 2013). We observed 14 PBRS with CARMA and 8 of these 14 with
Herschel, acquiring full spectral scans from 55 micron to 200 micron. Outflows
are detected in CO (J=1-0) from 8 of 14 PBRS, with two additional tentative
detections; outflows are also detected from the outbursting protostar HOPS 223
(V2775 Ori) and the Class I protostar HOPS 68. The outflows have a range of
morphologies, some are spatially compact, <10000 AU in extent, while others
extend beyond the primary beam. The outflow velocities and morphologies are
consistent with being dominated by intermediate inclination angles (80 deg > i
> 20 deg). This confirms the interpretation of the very red 24 micron to 70
micron colors of the PBRS as a signpost of high envelope densities, with only
one (possibly two) cases of the red colors resulting from edge-on inclinations.
We detect high-J (J_up > 13) CO lines and/or H_2O lines from 5 of 8 PBRS and
only for those with detected CO outflows. The far-infrared CO rotation
temperatures of the detected PBRS are marginally colder (~230 K) than those
observed for most protostars (~300 K), and only one of these 5 PBRS has
detected [OI] 63 micron emission. The high envelope densities could be
obscuring some [OI] emission and cause a ~20 K reduction to the CO rotation
temperatures.


title:
Observational evidence for temporary planetary wave forcing of the MLT
  during fall equinox

abstract:
  We present direct observations of zonal wave numbers 1 and 2 planetary wave
activity in the mesopause region derived from a longitudinal chain of
high-latitude Northern Hemisphere (51-66$^{\circ}$N) Super Dual Auroral Radar
Network radars. Over a 9 year period (2000-2008), the planetary wave activity
observed shows a consistent increase around the fall equinox. This is shown to
be coincident with a minimum in the magnitude of the stratospheric winds and
consequently a minimum in the stratospheric gravity wave filtering and the
subsequent momentum deposition in the mesopause region. Despite this, the
observed meridional winds are shown to be perturbed poleward and mesopause
temperatures rise temporarily, suggesting that westward momentum deposition
from planetary waves temporarily becomes the dominant forcing on the mesopause
region each fall equinox.


title:
The nuclear quadrupole moment mesured with Nuclear Quadrupole Resonance
  NQR : Principle and definition

abstract:
  The nuclear quadruple moment is a fundamental character associated to the
nuclei, this moment is related to the not purely spherical distribution in the
nuclei, indeed its measure allows us to survey the geometric deformation of the
nuclei of its spherical shape. The measurement methods of the quadruple moment
is to study the electrical energy hyperfine interaction between the quadruple
moment and the electric field gradient due to atomics electrons, one of the
methods is the nuclear quadruple resonance NQR which is observed at the
transitions between energy levels splits by the effect of the quadruple
interaction and induced by a radio frequency field.


title: Final combined deep inelastic scattering cross sections at HERA

abstract:
  The combination is presented of all inclusive deep inelastic scattering cross
sections previously published by the H1 and ZEUS collaborations at HERA for
neutral and charged current $ep$ scattering for zero beam polarisation. The
data were taken at proton beam energies of 920, 820, 575 and 460 GeV and an
electron beam energy of 27.5 GeV. The data correspond to an integrated
luminosity of about 1 fb$^{-1}$ and span six orders of magnitude in negative
four-momentum-transfer squared, $Q^2$, and Bjorken $x$. The correlations of the
systematic uncertainties were evaluated and taken into account for the
combination. The combined cross sections were input to QCD analyses at leading
order, next-to-leading order and at next-to-next-to-leading order, providing a
new set of parton distribution functions, called HERAPDF2.0. Additionally, the
inclusion of jet-production cross sections made a simultaneous and precise
determination of parton distributions and the strong coupling constant
possible. Brief highlights of the results are presented.


title:
Formal analysis of HTM Spatial Pooler performance under predefined
  operation conditions

abstract:
  This paper introduces mathematical formalism for Spatial (SP) of Hierarchical
Temporal Memory (HTM) with a spacial consideration for its hardware
implementation. Performance of HTM network and its ability to learn and adjust
to a problem at hand is governed by a large set of parameters. Most of
parameters are codependent which makes creating efficient HTM-based solutions
challenging. It requires profound knowledge of the settings and their impact on
the performance of system. Consequently, this paper introduced a set of
formulas which are to facilitate the design process by enhancing tedious
trial-and-error method with a tool for choosing initial parameters which enable
quick learning convergence. This is especially important in hardware
implementations which are constrained by the limited resources of a platform.
The authors focused especially on a formalism of Spatial Pooler and derive at
the formulas for quality and convergence of the model. This may be considered
as recipes for designing efficient HTM models for given input patterns.


title: The ubiquitous photonic wheel

abstract:
  A circularly polarized electromagnetic plane wave carries an electric field
that rotates clockwise or counterclockwise around the propagation direction of
the wave. According to the handedness of this rotation, its \emph{longitudinal}
spin angular momentum density is either parallel or antiparallel to the
propagation of light. However, there are also light waves that are not simply
plane and carry an electric field that rotates around an axis perpendicular to
the propagation direction, thus yielding \emph{transverse} spin angular
momentum density. Electric field configurations of this kind have been
suggestively dubbed "photonic wheels". It has been recently shown that photonic
wheels are commonplace in optics as they occur in electromagnetic fields
confined by waveguides, in strongly focused beams, in plasmonic and evanescent
waves. In this work we establish a general theory of electromagnetic waves
{propagating along a well defined direction, which carry} transverse spin
angular momentum density. We show that depending on the shape of {these waves,
the} spin density may be either perpendicular to the \emph{mean} linear
momentum (globally transverse spin) or to the linear momentum \emph{density}
(locally transverse spin). We find that the latter case generically occurs only
for non-diffracting beams, such as the Bessel beams. Moreover, we introduce the
concept of \emph{meridional} Stokes parameters to operationally quantify the
transverse spin density. To illustrate our theory, we apply it to the exemplary
cases of Bessel beams and evanescent waves. These results open a new and
accessible route to the understanding, generation and manipulation of optical
beams with transverse spin angular momentum density.


title:
$Q-\Phi$ criticality in the extended phase space of $(n+1)$-dimensional
  RN-AdS black holes

abstract:
  In order to achieve a deeper understanding of gravity theories, it is
important to further investigate the thermodynamic properties of black hole at
the critical point, besides the phase transition and critical behaviors. In
this paper, by using Maxwell's equal area law, we choose $T,Q,\Phi$ as the
state parameters and study the phase equilibrium problem of general
$(n+1)$-dimensional RN-AdS black holes thermodynamic system. The boundary of
the two-phase coexistence region and its isotherm and isopotential lines are
presented, which may provide theoretical foundation for studying the phase
transition and phase structure of black hole systems.


title: Single-top production in the s-channel and the top-quark mass

abstract:
  We use a fixed-order expansion of resummed soft-gluon corrections to
determine an approximate NNLO formula for the partonic cross section of
single-top production in the $s$-channel. This formula is implemented in the
program Hathor for the numerical evaluation of hadronic cross sections. With
the resulting code, we perform a fit of the top-quark mass to Tevatron cross
section data. Results for $m_t$ are given in the pole-mass scheme and in the
$\overline{\mathrm{MS}}$ scheme.


title:
Generalized type IIB supergravity equations and non-Abelian classical
  r-matrices

abstract:
  We study Yang-Baxter deformations of the $AdS_5 \times S^5$ superstring with
non-Abelian classical $r$-matrices which satisfy the homogeneous classical
Yang-Baxter equation (CYBE). By performing a supercoset construction, we can
get deformed $AdS_5 \times S^5$ backgrounds. While this is a new area of
research, the current understanding is that Abelian classical $r$-matrices give
rise to solutions of type IIB supergravity, while non-Abelian classical
$r$-matrices lead to solutions of the generalized supergravity equations. We
examine here some examples of non-Abelian classical r-matrices and derive the
associated backgrounds explicitly. All of the resulting backgrounds satisfy the
generalized equations. For some of them, we derive "T-dualized" backgrounds by
adding a linear coordinate dependence to the dilaton and show that these
satisfy the usual type IIB supergravity equations. Remarkably, some of the
"T-dualized" backgrounds are locally identical to undeformed $AdS_5 \times S^5$
after an appropriate coordinate transformation, but this seems not to be
generally the case.


title:
GPS scintillation and irregularities at the front of an ionization
  tongue in the nightside polar ionosphere

abstract:
  In this paper we study a tongue of ionization (TOI) on 31 October 2011 which
stretched across the polar cap from the Canadian dayside sector to Svalbard in
the nightside ionosphere. The TOI front arrived over Svalbard around 1930 UT.
We have investigated GPS scintillation and irregularities in relation to this
TOI front. This is the first study presenting such detailed multi-instrument
data of scintillation and irregularities in relation to a TOI front. Combining
data from an all-sky imager, the European Incoherent Scatter Svalbard Radar,
the Super Dual Auroral Radar Network Hankasalmi radar, and three GPS
scintillation and total electron content (TEC) monitors in Longyearbyen and
Ny-{\AA}lesund, we observe bursts of phase scintillation and no amplitude
scintillation in relation to the leading gradient of the TOI. Spectrograms of
50 Hz phase measurements show highly localized and variable structuring of the
TOI leading gradient, with no structuring or scintillation within the TOI or
ahead of the TOI.


title: Generalized Effective Operator Formalism for Decaying Systems

abstract:
  Systems of neutral kaons can be used to observe entanglement and the
violation of Bell inequalities. The decay of these particles poses some
problems, however, and recently an effective formalism for treating such
systems has been derived. We generalize this formalism and make it applicable
to other quantum systems that can be made to behave in a similar manner. As
examples, we discuss two possible implementations of the generalized formalism
using trapped ions such as $^{171}$Yb or $^{172}$Yb, which may be used to
simulate kaonic behavior in a quantum optical system.


title: The Finiteness Threshold Width of Lattice Polytopes

abstract:
  We prove that in each dimension $d$ there is a constant $w^\infty(d)\in
\mathbb{N}$ such that for every $n\in \mathbb{N}$ all but finitely many
$d$-polytopes with $n$ lattice points have width at most $w^\infty(d)$. We call
$w^\infty(d)$ the finiteness threshold width and show that $d-2 \le
w^\infty(d)\le O^*\left( d^{4/3}\right)$.
  Blanco and Santos determined the value $w^\infty(3)=1$. Here, we establish
$w^\infty(4)=2$. This implies, in particular, that there are only finitely many
empty $4$-simplices of width larger than two.
  The main tool in our proofs is the study of $d$-dimensional lifts of hollow
$(d-1)$-polytopes.


title:
Spin-1/2 sub-dynamics nested in the quantum dynamics of two coupled
  qutrits

abstract:
  In this paper we investigate the quantum dynamics of two spin-1 systems,
$\vec{\textbf{S}}_1$ and $\vec{\textbf{S}}_2$, adopting a generalized
$(\vec{\textbf{S}}_1+\vec{\textbf{S}}_2)^2$-nonconserving Heisenberg model. We
show that, due to its symmetry property, the nine-dimensional dynamics of the
two qutrits exactly decouples into the direct sum of two sub-dynamics living in
two orthogonal four- and five-dimensional subspaces. Such a reduction is
further strengthened by our central result consisting in the fact that in the
four-dimensional dynamically invariant subspace, the two qutrits quantum
dynamics, with no approximations, is equivalent to that of two non interacting
spin 1/2's. The interpretative advantages stemming from such a remarkable and
non-intuitive nesting are systematically exploited and various intriguing
features consequently emerging in the dynamics of the two qutrits are deeply
scrutinised. The possibility of exploiting the dynamical reduction brought to
light in this paper for exactly treating as well time-dependent versions of our
Hamiltonian model is briefly discussed.


title:
Gaussian Message Passing Iterative Detection for MIMO-NOMA Systems with
  Massive Access

abstract:
  This paper considers a low-complexity Gaussian Message Passing Iterative
Detection (GMPID) algorithm for Multiple-Input Multiple-Output systems with
Non-Orthogonal Multiple Access (MIMO-NOMA), in which a base station with $N_r$
antennas serves $N_u$ sources simultaneously. Both $N_u$ and $N_r$ are very
large numbers and we consider the cases that $N_u>N_r$. The GMPID is based on a
fully connected loopy graph, which is well understood to be not convergent in
some cases. The large-scale property of the MIMO-NOMA is used to simplify the
convergence analysis. Firstly, we prove that the variances of the GMPID
definitely converge to that of Minimum Mean Square Error (MMSE) detection.
Secondly, two sufficient conditions that the means of the GMPID converge to a
higher MSE than that of the MMSE detection are proposed. However, the means of
the GMPID may still not converge when $ N_u/N_r< (\sqrt{2}-1)^{-2}$. Therefore,
a new convergent SA-GMPID is proposed, which converges to the MMSE detection
for any $N_u> N_r$ with a faster convergence speed. Finally, numerical results
are provided to verify the validity of the proposed theoretical results.


title: Honey Sheets: What Happens to Leaked Google Spreadsheets?

abstract:
  Cloud-based documents are inherently valuable, due to the volume and nature
of sensitive personal and business content stored in them. Despite the
importance of such documents to Internet users, there are still large gaps in
the understanding of what cybercriminals do when they illicitly get access to
them by for example compromising the account credentials they are associated
with. In this paper, we present a system able to monitor user activity on
Google spreadsheets. We populated 5 Google spreadsheets with fake bank account
details and fake funds transfer links. Each spreadsheet was configured to
report details of accesses and clicks on links back to us. To study how people
interact with these spreadsheets in case they are leaked, we posted unique
links pointing to the spreadsheets on a popular paste site. We then monitored
activity in the accounts for 72 days, and observed 165 accesses in total. We
were able to observe interesting modifications to these spreadsheets performed
by illicit accesses. For instance, we observed deletion of some fake bank
account information, in addition to insults and warnings that some visitors
entered in some of the spreadsheets. Our preliminary results show that our
system can be used to shed light on cybercriminal behavior with regards to
leaked online documents.


title:
On the center of the quantized enveloping algebra of a simple Lie
  algebra

abstract:
  Let $\frak{g}$ be a finite dimensional simple complex Lie algebra and
$U=U_q(\frak{g})$ the quantized enveloping algebra (in the sense of Jantzen)
with $q$ being generic. In this paper, we show that the center
$Z(U_q(\frak{g}))$ of the quantum group $U_q(\frak{g})$ is isomorphic to a
monoid algebra, and that $Z(U_q(\frak{g}))$ is a polynomial algebra if and only
if $\frak{g}$ is of type $A_1, B_n, C_n, D_{2k+2}, E_7, E_8, F_4$ or $G_2.$
Moreover, in case $\frak{g}$ is of type $D_{n}$ with $n$ odd, then
$Z(U_q(\frak{g}))$ is isomorphic to a quotient algebra of a polynomial algebra
in $n+1$ variables with one relation; in case $\frak{g}$ is of type $E_6$, then
$Z(U_q(\frak{g}))$ is isomorphic to a quotient algebra of a polynomial algebra
in fourteen variables with eight relations; in case $\frak{g}$ is of type
$A_{n}$, then $Z(U_q(\frak{g}))$ is isomorphic to a quotient algebra of a
polynomial algebra described by $n$-sequences.


title:
A Tail of Two Populations: Chemo-dynamics of the Sagittarius Stream and
  Implications for its Original Mass

abstract:
  We use the SDSS/SEGUE spectroscopic sample of stars in the leading and
trailing streams of the Sagittarius (Sgr) to demonstrate the existence of two
sub-populations with distinct chemistry and kinematics. The metallicity
distribution function (MDF) of the trailing stream is decomposed into two
Gaussians describing a metal-rich sub-population with means and dispersions
(-0.74, 0.18) dex and a metal-poor with (-1.33, 0.27) dex. The metal-rich
sub-population has a velocity dispersion ~ 8 km/s, whilst the metal-poor is
nearly twice as hot ~13 km/s. For the leading stream, the MDF is again
well-described by a superposition of two Gaussians, though somewhat shifted as
compared to the trailing stream. The metal-rich has mean and dispersion (-1.00,
0.34) dex, the metal-poor (-1.39, 0.22) dex. The velocity dispersions are
inflated by projection effects to give 15 - 30 km/s for the metal-poor, and 6 -
20 km/s for the metal-rich, depending on longitude. We infer that, like many
dwarf spheroidals, the Sgr progenitor possessed a more extended, metal-poor
stellar component and less extended, metal-rich one. We study the implications
of this result for the progenitor mass by simulating the disruption of the Sgr,
represented as King light profiles in dark halos of masses between $10^{10}$
and $10^{11} M_\odot$, in a three-component Milky Way whose halo is a live
Truncated Flat potential in the first phase of accretion and a triaxial Law \&
Majewski model in the second phase. We show that that the dark halo of the Sgr
must have been $\gtrsim 6 \times 10^{10} M_\odot$ to reproduce the run of
velocity dispersion with longitude for the metal-rich and metal-poor
sub-populations in the tails.


title: Counting Contours on Trees

abstract:
  We calculate the exact number of contours of size $n$ containing a fixed
vertex in $d$-ary trees and provide sharp estimates for this number for more
general trees. We also obtain a characterization of the locally finite trees
with infinitely many contours of the same size containing a fixed vertex.


title:
Pathwise error bounds in Multiscale variable splitting methods for
  spatial stochastic kinetics

abstract:
  Stochastic computational models in the form of pure jump processes occur
frequently in the description of chemical reactive processes, of ion channel
dynamics, and of the spread of infections in populations. For spatially
extended models, the computational complexity can be rather high such that
approximate multiscale models are attractive alternatives. Within this
framework some variables are described stochastically, while others are
approximated with a macroscopic point value.
  We devise theoretical tools for analyzing the pathwise multiscale convergence
of this type of variable splitting methods, aiming specifically at spatially
extended models. Notably, the conditions we develop guarantee well-posedness of
the approximations without requiring explicit assumptions of \textit{a priori}
bounded solutions. We are also able to quantify the effect of the different
sources of errors, namely the \emph{multiscale error} and the \emph{splitting
error}, respectively, by developing suitable error bounds. Computational
experiments on selected problems serve to illustrate our findings.


title:
Towards Model Selection for Local Log-Density Estimation. Fisher and
  Wilks-type theorems

abstract:
  The aim of this research is to make a step towards providing a tool for model
selection for log-density estimation. The author revisits the procedure for
local log-density estimation suggested by Clive Loader (1996) and extends the
theoretical results to finite-sample framework with the help of machinery of
Spokoiny (2012). The results include bias expression from "deterministic"
counterpart and Fisher and Wilks-type theorems from "stochastic". We elaborate
on bandwidth trade-off $ h(n) = \arg\min O(h^p) + O_p(1/\sqrt{nh^d}) $ with
explicit constants at big O notation.
  Explicit expressions involve (i) true density function and (ii) model that is
selected (dimension, bandwidth, kernel and basis, e.g. polynomial). Existing
asymptotic properties directly follow from our results. From the expressions
obtained it is possible to control "the curse of dimension" both from the side
of log-density smoothness and the inner space dimension.


title:
Bracket-Preserving property of Anchor Maps and Applications to Various
  Brackets

abstract:
  Let $E \rightarrow M$ be a smooth vector bundle with a bilinear product on
$\Gamma(E)$ satisfying the Jacobi identity. Assuming only the existence of an
anchor map $\mathfrak{a}$ we show that $\mathfrak{a}([X,Y]) =
[\mathfrak{a}X,\mathfrak{a}Y]_c$. This gives the redundancy of the homomorphism
condition in the definition of Leibniz algebroid (in particular if it arises
from a Nambu-Poisson manifold); an aspect not addressed in the literature. We
apply our result to the brackets of Hagiwara, Ibanez et. al; we settle an old
query of Uchino on redundancy for Courant bracket.


title: High sensitivity fluid energy harvester

abstract:
  An ambient energy harvesting device was design and fabricated. It can harness
kinetic energy of rain droplets and low velocity wind flows. The energy
converted into electrical energy by using a single device. The technique used
by the device was based on the principles of electromagnetic induction and
cantilever. Readily available materials were characterized and used for the
fabrication of cantilever. Under the laboratory conditions, water droplets
having diameter 4mm and wind with speed 0.5m/s were used as the two distinct
sources. Without making any changes in the geometry or the materials used, the
device was able to convert kinetic energy from both the sources to provide
voltage in the range of 0.7-1VAC. The work was conceptualized to provide an
autonomous device which can harness energy from both the renewable energy
sources.


title:
Optimal control of a rate-independent evolution equation via viscous
  regularization

abstract:
  We study the optimal control of a rate-independent system that is driven by a
convex, quadratic energy. Since the associated solution mapping is non-smooth,
the analysis of such control problems is challenging. In order to derive
optimality conditions, we study the regularization of the problem via a
smoothing of the dissipation potential and via the addition of some viscosity.
The resulting regularized optimal control problem is analyzed. By driving the
regularization parameter to zero, we obtain a necessary optimality condition
for the original, non-smooth problem.


title: A new proposal for diphoton resonance from $E_6$ motivated extra $U(1)$

abstract:
  We propose that the diphoton resonance signal indicated by the recent LHC
data might also arise from the pair productions of vector-like heavy down-type
quarks with mass around $750$ GeV and above. The vector-like quark decays into
an ordinary light quark and a Standard Model singlet scalar. The subsequent
decay of scalar singlet produces the diphoton excess. Both the vector-like
quark and singlet scalars appear naturally in the $E_6$, and their masses can
be in the TeV scale with a suitable choice of symmetry breaking pattern. The
prediction of such a proposal would be to see an accompanying dijet signal at
the same mass with similar cross section in the $2\gamma + 2j$ final state and
two dijet resonances at the same mass for a $4j$ final state with a cross
section, about 100 times larger. Both predictions can be tested easily as the
luminosity accumulates in the upcoming runs of the LHC.


title: 2-tape 1-way Quantum Finite State Automata

abstract:
  1-way quantum finite state automata are reversible in nature, which greatly
reduces its accepting property. In fact, the set of languages accepted by 1-way
quantum finite automata is a proper subset of regular languages. We introduce
2-tape 1-way quantum finite state automaton (2T1QFA(2))which is a modified
version of 1-way 2-head quantum finite state automaton(1QFA(2)). In this paper,
we replace the single tape of 1-way 2-head quantum finite state automaton with
two tapes. The content of the second tape is determined using a relation
defined on input alphabet. The main claims of this paper are as follows: (1)We
establish that 2-tape 1-way quantum finite state automaton(2T1QFA(2)) can
accept all regular languages (2)A language which cannot be accepted by any
multi-head deterministic finite automaton can be accepted by 2-tape 1-way
quantum finite state automaton(2T1QFA(2)) .(3) Exploiting the superposition
property of quantum automata we show that 2-tape 1-way quantum finite state
automaton(2T1QFA(2)) can accept the language L=ww.


title: Analogy of QCD hadronization and Hawking-Unruh radiation at NICA

abstract:
  The proposed analogy of particle production from high-energy collisions and
Hawking-Unruh radiation from black holes is extended to finite density
(collisions) and finite-electric charge (black holes). Assuming that the
electric charge is directly proportional to the density (or the chemical
potential), it becomes clear that for at least two freezeout conditions;
constant $s/T^3$ and $E/N$, the proposed analogy works very well. Dependence of
radiation (freezeout) temperature on finite electric-charge leads to an
excellent estimation for Kaon-to-pion ratio, for instance, especially in the
energy range covered by NICA. The precise and complete measurements for various
light-flavored particle yields and ratios are essential in characterizing
Hawing-Unruh radiation from charged black holes and the QCD hadronization at
finite density, as well.


title: Query Answering with Transitive and Linear-Ordered Data

abstract:
  We consider entailment problems involving powerful constraint languages such
as guarded existential rules, in which additional semantic restrictions are put
on a set of distinguished relations. We consider restricting a relation to be
transitive, restricting a relation to be the transitive closure of another
relation, and restricting a relation to be a linear order. We give some natural
generalizations of guardedness that allow inference to be decidable in each
case, and isolate the complexity of the corresponding decision problems.
Finally we show that slight changes in our conditions lead to undecidability.


title:
A New Method to Optimize Finite Dimensions Thermodynamic Models:
  application to an Irreversible Stirling Engine

abstract:
  Different economical configurations, due for instance to the relative cost of
the fuel it consumes, can push a heat engine into operating whether at maximum
efficiency or at maximum power produced. Any relevant design of such system
hence needs to be based, at least partly, on the knowledge of its specific
"power vs. efficiency" characteristic curve. However, even when a simple model
is used to describe the engine, obtained for example thanks to Finite
Dimensions Thermodynamics, such characteristic curve is often difficult to
obtain and takes an explicit form only for the simplest of these models. When
more realistic models are considered, including complex internal subsystems or
processes, an explicit expression for this curve is practically impossible to
obtain. In this paper, we propose to use the called Graham's scan algorithm in
order to directly obtain the power vs. efficiency curve of a realistic Stirling
engine model, which includes heat leakage, regenerator effectiveness, as well
as internal and external irreversibilities. Coupled with an adapted
optimization routine, this approach allows to design and optimize the same way
simple or complex heat engine models. Such method can then be useful during the
practical design task of any thermal power converter, almost regardless to its
own internal complexity.


title: Lepton flavor violating quarkonium decays

abstract:
  We argue that lepton flavor violating (LFV) decays $M \to \ell_1 \overline
\ell_2$ of quarkonium states $M$ with different quantum numbers could be used
to put constraints on the Wilson coefficients of effective operators describing
LFV interactions at low energy scales. We note that restricted kinematics of
the two-body quarkonium decays allows us to select operators with particular
quantum numbers, significantly reducing the reliance on the single operator
dominance assumption that is prevalent in constraining parameters of the
effective LFV Lagrangian. We shall also argue that studies of radiative lepton
flavor violating $M \to \gamma \ell_1 \overline \ell_2$ decays could provide
important complementary access to those effective operators.


title:
Time for dithering: fast and quantized random embeddings via the
  restricted isometry property

abstract:
  Recently, many works have focused on the characterization of non-linear
dimensionality reduction methods obtained by quantizing linear embeddings,
e.g., to reach fast processing time, efficient data compression procedures,
novel geometry-preserving embeddings or to estimate the information/bits stored
in this reduced data representation. In this work, we prove that many linear
maps known to respect the restricted isometry property (RIP) can induce a
quantized random embedding with controllable multiplicative and additive
distortions with respect to the pairwise distances of the data points beings
considered. In other words, linear matrices having fast matrix-vector
multiplication algorithms (e.g., based on partial Fourier ensembles or on the
adjacency matrix of unbalanced expanders) can be readily used in the definition
of fast quantized embeddings with small distortions. This implication is made
possible by applying right after the linear map an additive and random "dither"
that stabilizes the impact of the uniform scalar quantization operator applied
afterwards. For different categories of RIP matrices, i.e., for different
linear embeddings of a metric space $(\mathcal K \subset \mathbb R^n, \ell_q)$
in $(\mathbb R^m, \ell_p)$ with $p,q \geq 1$, we derive upper bounds on the
additive distortion induced by quantization, showing that it decays either when
the embedding dimension $m$ increases or when the distance of a pair of
embedded vectors in $\mathcal K$ decreases. Finally, we develop a novel
"bi-dithered" quantization scheme, which allows for a reduced distortion that
decreases when the embedding dimension grows and independently of the
considered pair of vectors.


title: Precise measurements of inflationary features with 21 cm observations

abstract:
  Future observations of 21~cm emission using HI intensity mapping will enable
us to probe the large scale structure of the Universe over very large survey
volumes within a reasonable observation time. We demonstrate that the
three-dimensional information contained in such surveys will be an extremely
powerful tool in searching for features that were imprinted in the primordial
power spectrum and bispectrum during inflation. Here we focus on the "resonant"
and "step" inflation models, and forecast the potential of upcoming 21~cm
experiments to detect these inflationary features in the observable power- and
bispectrum. We find that the full scale Tianlai experiment and the Square
Kilometre Array (SKA) have the potential to improve on the sensitivity of
current Cosmic Microwave Background (CMB) experiments by several orders of
magnitude.


title: Large Cross-Phase Modulations at the Few-Photon Level

abstract:
  We demonstrate an efficient cross-phase modulation (XPM) based on a
closed-loop double-{\Lambda} system. The property of the double-{\Lambda}
medium can be controlled by changing the phases of the applied optical fields.
This phase-dependent XPM scheme can achieve large phase modulations at
low-light intensities without requiring cavities or tightly focusing of laser
beams. With this scheme, we observe a {\pi}-level phase shift with two pulses
both consisting of 8 photons in cold rubidium atoms. Such novel scheme provides
a simple route to generate strong interactions between photons and may have
potential applications in all-optical quantum signal processing.


title: Understanding the Abstract Dialectical Framework (Preliminary Report)

abstract:
  Among the most general structures extending the framework by Dung are the
abstract dialectical frameworks (ADFs). They come equipped with various types
of semantics, with the most prominent - the labeling-based one - analyzed in
the context of computational complexity, signatures, instantiations and
software support. This makes the abstract dialectical frameworks valuable tools
for argumentation. However, there are fewer results available concerning the
relation between the ADFs and other argumentation frameworks. In this paper we
would like to address this issue by introducing a number of translations from
various formalisms into ADFs. The results of our study show the similarities
and differences between them, thus promoting the use and understanding of ADFs.
Moreover, our analysis also proves their capability to model many of the
existing frameworks, including those that go beyond the attack relation.
Finally, translations allow other structures to benefit from the research on
ADFs in general and from the existing software in particular.


title:
The interior rotation of a sample of gamma Doradus stars from ensemble
  modelling of their gravity mode period spacings

abstract:
  CONTEXT. Gamma Doradus stars (hereafter gamma Dor stars) are known to exhibit
gravity- and/or gravito-intertial modes that probe the inner stellar region
near the convective core boundary. The non-equidistant spacing of the pulsation
periods is an observational signature of the stars' evolution and current
internal structure and is heavily influenced by rotation.
  AIMS. We aim to constrain the near-core rotation rates for a sample of gamma
Dor stars, for which we have detected period spacing patterns.
  METHODS. We combined the asymptotic period spacing with the traditional
approximation of stellar pulsation to fit the observed period spacing patterns
using chi-squared optimisation. The method was applied to the observed period
spacing patterns of a sample of stars and used for ensemble modelling.
  RESULTS. For the majority of stars with an observed period spacing pattern we
successfully determined the rotation rates and the asymptotic period spacing
values, though the uncertainty margins on the latter were typically large. This
also resulted directly in the identification of the modes corresponding with
the detected pulsation frequencies, which for most stars were prograde dipole
gravity and gravito-inertial modes. The majority of the observed retrograde
modes were found to be Rossby modes. We further discuss the limitations of the
method due to the neglect of the centrifugal force and the incomplete treatment
of the Coriolis force.
  CONCLUSION. Despite its current limitations, the proposed methodology was
successful to derive the rotation rates and to identify the modes from the
observed period spacing patterns. It forms the first step towards detailed
seismic modelling based on observed period spacing patterns of moderately to
rapidly rotating gamma Dor stars.


title: Ultra-high vacuum compatible induction-heated rod casting furnace

abstract:
  We report the design of a radio-frequency induction-heated rod casting
furnace that permits the preparation of polycrystalline ingots of intermetallic
compounds under ultra-high vacuum compatible conditions. The central part of
the system is a bespoke water-cooled Hukin crucible supporting a casting mold.
Depending on the choice of mold, typical rods have a diameter between 6 mm and
10 mm and a length up to 90 mm, suitable for single-crystal growth by means of
float-zoning. The setup is all-metal sealed and may be baked out. We find that
the resulting ultra-high vacuum represents an important precondition for
processing compounds with high vapor pressures under a high-purity argon
atmosphere up to 3 bar. Using the rod casting furnace, we succeeded to prepare
large high-quality single crystals of two half-Heusler compounds, namely the
itinerant antiferromagnet CuMnSb and the half-metallic ferromagnet NiMnSb.


title:
One-loop renormalization of the chiral Lagrangian for spinless matter
  fields in the SU(N) fundamental representation

abstract:
  We perform the leading one-loop renormalization of the chiral Lagrangian for
spinless matter fields living in the fundamental representation of SU(N). The
Lagrangian can also be applied to any theory with a spontaneous symmetry
breaking of $SU(N)_L\times SU(N)_R$ to $SU(N)_V$ and spinless matter fields in
the fundamental representation. For QCD, the matter fields can be kaons or
pseudoscalar heavy mesons. Using the background field method and heat kernel
expansion techniques, the divergences of the one-loop effective generating
functional for correlation functions of single matter fields are calculated up
to $\mathcal{O}(p^3)$. They are absorbed by counterterms not only from the
third order but also from the second order chiral Lagrangian.


title:
Hydrodynamic theory for nematic shells: the interplay among curvature,
  flow and alignment

abstract:
  We derive the hydrodynamic equations for nematic liquid crystals lying on
curved substrates. We invoke the Lagrange-Rayleigh variational principle to
adapt the Ericksen-Leslie theory to two-dimensional nematics in which a
degenerate anchoring of the molecules on the substrate is enforced. The only
constitutive assumptions in this scheme concern the free-energy density, given
by the two-dimensional Frank potential, and the density of dissipation which is
required to satisfy appropriate invariance requirements. The resulting
equations of motion couple the velocity field, the director alignment and the
curvature of the shell. To illustrate our findings, we consider the effect of a
simple shear flow on the alignment of a nematic lying on a cylindrical shell.


title: Large-scale-vortex dynamos in planar rotating convection

abstract:
  Several recent studies have demonstrated how large-scale vortices may arise
spontaneously in rotating planar convection. Here we examine the dynamo
properties of such flows in rotating Boussinesq convection. For moderate values
of the magnetic Reynolds number ($100 \lesssim Rm \lesssim 550$, with $Rm$
based on the box depth and the convective velocity), a large-scale (i.e.
system-size) magnetic field is generated. The amplitude of the magnetic energy
oscillates in time, nearly out of phase with the oscillating amplitude of the
large-scale vortex. The large-scale vortex is disrupted once the magnetic field
reaches a critical strength, showing that these oscillations are of magnetic
origin. The dynamo mechanism relies on those components of the flow that have
length scales lying between that of the large-scale vortex and the typical
convective cell size; smaller-scale flows are not required. The large-scale
vortex plays a crucial role in the magnetic induction despite being essentially
two-dimensional; we thus refer to this dynamo as a large-scale-vortex dynamo.
For larger magnetic Reynolds numbers, the dynamo is small scale, with a
magnetic energy spectrum that peaks at the scale of the convective cells. In
this case, the small-scale magnetic field continuously suppresses the
large-scale vortex by disrupting the correlations between the convective
velocities that allow it to form. The suppression of the large-scale vortex at
high $Rm$ therefore probably limits the relevance of the large-scale-vortex
dynamo to astrophysical objects with moderate values of $Rm$, such as planets.
In this context, the ability of the large-scale-vortex dynamo to operate at low
magnetic Prandtl numbers is of great interest.

categories: physics.flu-dyn astro-ph.EP astro-ph.SR physics.geo-ph


title:
Garbage Collection in JyNI - How to bridge Mark/Sweep and Reference
  Counting GC

abstract:
  Jython is a Java-based Python implementation and the most seamless way to
integrate Python and Java. It achieves high efficiency by compiling Python code
to Java bytecode and thus letting Java's JIT optimize it - an approach that
enables Python code to call Java functions or to subclass Java classes. It
enables Python code to leverage Java's multithreading features and utilizes
Java's built-in garbage collection (GC). However, it currently does not support
CPython's C-API and thus does not support native extensions like NumPy and
SciPy. Since most scientific code depends on such extensions, it is not
runnable with Jython. Jython Native Interface (JyNI) is a compatibility layer
that aims to provide CPython's native C extension API on top of Jython. JyNI is
implemented using the Java Native Interface (JNI) and its native part is
designed to be binary compatible with existing extension builds [...].


title: Quantum Oscillations from Fermi Sea

abstract:
  Quantum oscillations are conventionally understood to arise from the Fermi
level; hence, they are considered to be a proof of the existence of an
underlying Fermi surface. In this article, we show that in certain situations
quantum oscillations can also arise from inside the Fermi sea. We establish
this analytically, supporting it with numerical calculations. Possible
scenarios where such unusual behavior can occur are pointed out. In particular,
in strongly particle-hole asymmetric insulators, models of which have been
recently used in the context of the topological Kondo insulator SmB$_6$, we
show that the oscillations arise from inside the filled band, and are not
related to the gap.


title:
Preventing Malware Pandemics in Mobile Devices by Establishing
  Response-time Bounds

abstract:
  We study the propagation of a malicious software in a network of mobile
devices, which are moving in a specific city area, and establish time bounds
for the activation of a counter-measure, i.e., an antivirus or a cleaner in
order to prevent pandemic. More precisely, given an initial infected population
(mobile devices), we establish upper bounds on the time needed for a
counter-measure to take effect after infection (response-time), in order to
prevent the rest susceptible devices to get infected. Thus, within a period of
time, we guarantee that not all the susceptible devices in the city get
infected and the infected ones get sanitized. In our work, we first propose a
malware propagation model along with a device mobility model and then,
utilizing these models, we develop a simulator that we use to study the spread
of malware in such networks. Finally, we provide experimental results for the
pandemic prevention taken by our simulator for various response-time intervals.


title: Robust and adjustable C-shaped vortex beams

abstract:
  Wavefront engineering is an important quantum technology. Here, we
demonstrate the design and production of a robust C-shaped and orbital angular
momentum (OAM) carrying beam in which the doughnut shaped structure contains an
adjustable gap. We find that the presence of the vortex line in the core of the
beam is crucial for the robustness of the C-shape against beam propagation. The
topological charge of the vortex core controls mainly the size of the C, while
its opening angle is controlled by the presence of vortex-anti-vortex loops. We
demonstrate the generation and characterisation of C-shaped electron vortex
beams, although the result is equally applicable to other quantum waves.
Applications of C-shaped vortex beams include lithography, dynamical atom
sorting and atomtronics.


title:
Topological Approach to Microcanonical Thermodynamics and Phase
  Transition of Interacting Classical Spins

abstract:
  We propose a topological approach suitable to establish a connection between
thermodynamics and topology in the microcanonical ensemble. Indeed, we report
on results that point to the possibility of describing {\it interacting
classical spin systems} in the thermodynamic limit, including the occurrence of
a phase transition, using topology arguments only. Our approach relies on Morse
theory, through the determination of the critical points of the potential
energy, which is the proper Morse function. Our main finding is to show that,
in the context of the studied classical models, the Euler characteristic
$\chi(E)$ embeds the necessary features for a correct description of several
magnetic thermodynamic quantities of the systems, such as the magnetization,
correlation function, susceptibility, and critical temperature. Despite the
classical nature of the studied models, such quantities are those that do not
violate the laws of thermodynamics [with the proviso that Van der Waals loop
states are mean field (MF) artifacts]. We also discuss the subtle connection
between our approach using the Euler entropy, defined by the logarithm of the
modulus of $\chi(E)$ per site, and that using the {\it Boltzmann}
microcanonical entropy. Moreover, the results suggest that the loss of
regularity in the Morse function is associated with the occurrence of unstable
and metastable thermodynamic solutions in the MF case. The reliability of our
approach is tested in two exactly soluble systems: the infinite-range and the
short-range $XY$ models in the presence of a magnetic field. In particular, we
confirm that the topological hypothesis holds for both the infinite-range ($T_c
\neq 0$) and the short-range ($T_c = 0$) $XY$ models. Further studies are very
desirable in order to clarify the extension of the validity of our proposal.


title:
A probability-free and continuous-time explanation of the equity premium
  and CAPM

abstract:
  This paper gives yet another definition of game-theoretic probability in the
context of continuous-time idealized financial markets. Without making any
probabilistic assumptions (but assuming positive and continuous price paths),
we obtain a simple expression for the equity premium and derive a version of
the capital asset pricing model.


title:
Transversal-rotational and zero group velocity modes in tunable
  magneto-granular phononic crystals

abstract:
  We report on the design and operation of a 1D magneto-granular phononic
crystal composed of a chain of steel spherical beads on top of permanent
magnets. The magnetic field of the permanent magnets induces forces in the
granular structure. By changing its strength, we can tune the dynamic response
of the granular structure. We present experimental results with evidence of
coupled transversal-rotational modes, and zero group velocities modes. These
observations are well supported by a proposed model taking into account the
mechanical coupling between the beads and the magnets by linear stiffnesses and
including all degrees of freedom in translations and rotations.


title:
CGC/saturation approach: a new impact-parameter dependent model in the
  next-to-leading order of perturbative QCD

abstract:
  This paper is the first attempt to build CGC/saturation model based on the
next-to-leading order corrections to linear and non-linear evolution in QCD. We
assume that the renormalization scale is the saturation momentum and found that
the scattering amplitude has geometric scaling behaviour deep in the saturation
domain with the explicit formula of this behaviour at large $\tau = r^2 Q^2_s$.
We built a model that include this behaviour, as well as the ingredients that
has been known: (i) the behaviour of the scattering amplitude in the vicinity
of the saturation momentum, using the NLO BFKL kernel, (ii) the pre-asymptotic
behaviour of $\ln\Lb Q^2_s\Lb Y \Rb\Rb$, as function of $Y$ and (iii) the
impact parameter behaviour of the saturation momentum, which has exponential
behaviour $\propto \exp\Lb -\, m\, b\Rb$ at large $b$.We demonstrated that the
model is able to describe the experimental data for the deep inelastic
structure function. Despite this, our model has difficulties that are related
to the small value of the QCD coupling at $Q_s\Lb Y_0\Rb$ and the large values
of the saturation momentum, which indicate the theoretical inconsistency of our
description.


title: On the deformation of inversive distance circle packings, II

abstract:
  We show that the results in \cite{Ge-Jiang1} are still true in hyperbolic
background geometry setting, that is, the solution to Chow-Luo's combinatorial
Ricci flow can always be extended to a solution that exists for all time,
furthermore, the extended solution converges exponentially fast if and only if
there exists a metric with zero curvature. We also give some results about the
range of discrete Gaussian curvatures, which generalize Andreev-Thurston's
theorem to some extent.


title:
Microcalorimeter pulse analysis by means of principle component
  decomposition

abstract:
  The X-ray integral field unit for the Athena mission consists of a
microcalorimeter transition edge sensor pixel array. Incoming photons generate
pulses which are analyzed in terms of energy, in order to assemble the X-ray
spectrum. Usually this is done by means of optimal filtering in either time or
frequency domain.
  In this paper we investigate an alternative method by means of principle
component analysis. This method attempts to find the main components of an
orthogonal set of functions to describe the data.
  We show, based on simulations, what the influence of various instrumental
effects is on this type of analysis. We compare analyses both in time and
frequency domain. Finally we apply these analyses on real data, obtained via
frequency domain multiplexing readout.


title:
Infinite matter properties and zero-range limit of nonrelativistic
  finite-range interactions

abstract:
  We discuss some infinite matter properties of two finite-range interactions
widely used for nuclear structure calculations, namely Gogny and M3Y
interactions. We show that some useful informations can be deduced for the
central, tensor and spin-orbit terms from the spin-isospin channels and the
partial wave decomposition of the symmetric nuclear matter equation of state.
We show in particular that the central part of the Gogny interaction should
benefit from the introduction of a third Gaussian and the tensor parameters of
both interactions can be deduced from special combinations of partial waves. We
also discuss the fact that the spin-orbit of the M3Y interaction is not
compatible with local gauge invariance. Finally, we show that the zero-range
limit of both families of interactions coincides with the specific form of the
zero-range N3LO Skyrme interaction and we emphasize from this analogy the
benefits of N3LO.


title: Many-body quantum interference on hypercubes

abstract:
  Beyond the regime of distinguishable particles, many-body quantum
interferences influence quantum transport in an intricate manner. However,
symmetries of the single-particle transformation matrix alleviate this
complexity and even allow the analytic formulation of suppression laws, which
predict final states to occur with a vanishing probability due to total
destructive interference. Here we investigate the symmetries of hypercube
graphs and their generalizations with arbitrary identical subgraphs on all
vertices. We find that initial many-particle states, which are invariant under
self-inverse symmetries of the hypercube, lead to a large number of suppressed
final states. The condition for suppression is determined solely by the initial
symmetry, while the fraction of suppressed states is given by the number of
independent symmetries of the initial state. Our findings reveal new insights
into particle statistics for ensembles of indistinguishable bosons and fermions
and may represent a first step towards many-particle quantum protocols in
higher-dimensional structures.


title:
Measurement of the differential cross sections for top quark pair
  production as a function of kinematic event variables in pp collisions at
  sqrt(s) = 7 and 8 TeV

abstract:
  Measurements are reported of the normalized differential cross sections for
top quark pair production with respect to four kinematic event variables: the
missing transverse energy; the scalar sum of the jet transverse momentum (pT);
the scalar sum of the pT of all objects in the event; and the pT of
leptonically decaying W bosons from top quark decays. The data sample,
collected using the CMS detector at the LHC, consists of 5.0 inverse femtobarns
of proton-proton collisions at sqrt(s) = 7 TeV and 19.7 inverse femtobarns at
sqrt(s) = 8 TeV. Top quark pair events containing one electron or muon are
selected. The results are presented after correcting for detector effects to
allow direct comparison with theoretical predictions. No significant deviations
from the predictions of several standard model event simulation generators are
observed.


title:
1-loop mass generation by a constant external magnetic field for an
  electron propagating in a thin medium

abstract:
  The 1-loop self-energy of a Dirac electron of mass m propagating in a thin
medium simulating graphene in an external magnetic field B is investigated in
Quantum Field Theory. Equivalence is shown with the so-called reduced QED_{3+1}
on a 2-brane. Schwinger-like methods are used to calculate the self-mass \delta
m_{LLL} of the electron when it lies in the lowest Landau level. Unlike in
standard QED_{3+1}, it does not vanish at the limit m -> 0 :\delta m_{LLL} ->
(\alpha/2)\sqrt{pi/2}sqrt{\hbar|e|B/c^2}; all Landau levels of the virtual
electron are taken into account and on mass-shell renormalization conditions
are implemented. Restricting to the sole lowest Landau level of the virtual
electron is explicitly shown to be inadequate. Resummations at higher orders
lie beyond the scope of this work.


title: Simulating the Onset of Grazing Envelope Evolution of Binary Stars

abstract:
  We present the first three-dimensional gas-dynamical simulations of the
grazing envelope evolution (GEE) of stars, with the goal of exploring the basic
flow properties and the role of jets at the onset of the GEE. In the simulated
runs, a secondary main-sequence star grazes the envelope of the primary
asymptotic giant branch (AGB) star. The orbit is circular at the radius of the
AGB primary star on its equator. We inject two opposite jets perpendicular to
the equatorial plane from the location of the secondary star, and follow the
evolution for several orbital periods. We explore the flow pattern by which the
jets eject the outskirts of the AGB envelope. After one orbit the jets start to
interact with gas ejected in previous orbits and inflate hot low-density
bubbles.


title: Cylinders in del Pezzo fibrations

abstract:
  We show that a del Pezzo fibration $\pi$ : V $\rightarrow$ W of degre d
contains a vertical open cylinder, that is, an open subset whose intersection
with the generic fiber of $\pi$ is isomorphic to $Z\times\mathbb{A}_{K}^{1}$
for some quasi-projective variety Z defined over the function field K of W , if
and only if d $\ge$ 5 and $\pi$ : V $\rightarrow$ W admits a rational section.
We also construct twisted cylinders in total spaces of threefold del Pezzo
fibrations $\pi$ : V $\rightarrow$ P 1 of degree d $\le$ 4.


title:
HI absorption towards low luminosity radio-loud AGNs of different
  accretion modes and WISE colours

abstract:
  H{\sc i} absorption studies of active galaxies enable us to probe their
circumnuclear regions and the general interstellar medium, and study the supply
of gas which may trigger the nuclear activity. In this paper, we investigate
the detection rate of H{\sc i} absorption on the nature of radio galaxies based
on their emission-line spectra, nature of the host galaxies based on the
\textit{WISE} colours and their radio structure, which may help understand the
different accretion modes. We find significant difference in distributions of
W2$-$W3 colour for sources with H{\sc i} absorption detections and
non-detections. We report a high detection rate of H{\sc i} absorption in the
galaxies with \textit{WISE} infrared colours W2$-$W3 $>$ 2, which is typical of
gas-rich systems, along with a compact radio structure. The H{\sc i} detection
rate for low-excitation radio galaxies (LERGs) with W2$-$W3 $>$ 2 and compact
radio structure is high (70.6$\pm$20.4 \%). In HERGs, compact radio structure
in the nuclear or circumnuclear region could give rise to absorption by gas in
the dusty torus in addition to gas in the interstellar medium. However, higher
specific star formation rate (sSFR) for the LERGs with W2$-$W3 $>$ 2 suggests
that H{\sc i} absorption may be largely due to star-forming gas in their hosts.
LERGs with extended radio structure tend to have significantly lower values of
W2$-$W3 compared to those with compact structure. Extended radio sources and
those with W2$-$W3 $<$ 2 have low H{\sc i} detection rates.


title:
Subdiffusion in classical and quantum nonlinear Schr\"odinger equations
  with disorder

abstract:
  The review is concerned with the nonlinear Schr\"odinger equation (NLSE) in
the presence of disorder. Disorder leads to localization in the form of the
localized Anderson modes (AM), while nonlinearity is responsible for the
interaction between the AMs and transport. The dynamics of an initially
localized wave packets are concerned in both classical and quantum cases. In
both cases, there is a subdiffusive spreading, which is explained in the
framework of a continuous time random walk (CTRW), and it is shown that
subdiffusion is due to the transitions between those AMs, which are strongly
overlapped. This overlapping being a common feature of both classical and
quantum dynamics, leads to the clustering with an effective trapping of the
wave packet inside each cluster. Therefore, the dynamics of the wave packet
corresponds to the CTRW, where the basic mechanism of subdiffusion is an
entrapping of the wave packet with delay, or waiting, times distributed by the
power law $w(t)\sim 1/t^{1+\alpha}$, where $\alpha$ is the transport exponent.
It is obtained that $\alpha=1/3$ for the classical NLSE and $\alpha=1/2$ for
the quantum NLSE.


title:
The electron-phonon interaction with forward scattering peak is a
  relevant approach to high Tc superconductivity in FeSe films on SrTiO3 and
  TiO2

abstract:
  The theory of EPI with strong forward scattering peak (FSP)[1-3] is recently
applied in [4-5] in studying high Tc(~100 K) in a FeSe grown on SrTiO3 [4] and
TiO2 [6]. The EPI is due to a long-range dipolar electric field created by the
high-energy oxygen vibrations (E0~90 meV) at the interface [4-5]. Besides
obtaining new results we also correct some misleading results from the recent
literature. We show that the mean-field critical temperature Tc0 is an
interplay between the maximal pairing potential and the FSP-width qc. For
Tc0~100 K the gap (G) is G~16 meV in agreement with ARPES experiments. We find
that in leading order Tc0 is mass-independent and there is small oxygen isotope
effect in next to leading order. In clean systems Tc0 for s-wave and d-wave
pairing is degenerate but both are affected by non-magnetic impurities. The
non-magnetic impurities are pair-weakening in the s-channel and pair-breaking
in the d-channel. The normal state self-energy at the Fermi surface gives rise
to the ARPES quasiparticle band at E=0 and to a replica band at
Er=-E0(1+l(m))^1/2, respectively. The EPI coupling l(m), which enters the
self-energy, is mass-dependent - the fact overlooked in the literature, makes
at low energies the slope of the self-energy mass-dependent. The smallness of
the oxygen isotope effect in Tc0 and its presence in the self-energy in FeSe
films on SrTiO3 and TiO2 is a smoking-gun experiment for the application of the
EPI-FSP theory to these systems. The EPI-FSP theory predicts a large number of
low-laying pairing states (above the ground state) thus causing internal pair
fluctuations. The latter reduce Tc0 additionally, by creating a pseudogap state
for Tc<T<Tc0. Possibilities to increase Tc0 by designing novel structures are
discussed in the framework of the EPI-FSP theory.


title: Using the pyMIC Offload Module in PyFR

abstract:
  PyFR is an open-source high-order accurate computational fluid dynamics
solver for unstructured grids. It is designed to efficiently solve the
compressible Navier-Stokes equations on a range of hardware platforms,
including GPUs and CPUs. In this paper we will describe how the Python Offload
Infrastructure for the Intel Many Integrated Core Architecture (pyMIC) was used
to enable PyFR to run with near native performance on the Intel Xeon Phi
coprocessor. We will introduce the architecture of both pyMIC and PyFR and
present a variety of examples showcasing the capabilities of pyMIC. Further, we
will also compare the contrast pyMIC to other approaches including native
execution and OpenCL. The process of adding support for pyMIC into PyFR will be
described in detail. Benchmark results show that for a standard cylinder flow
problem PyFR with pyMIC is able achieve 240 GFLOP/s of sustained double
precision floating point performance; for a 1.85 times improvement over PyFR
with C/OpenMP on a 12 core Intel Xeon E5-2697 v2 CPU.


title: Spectral analysis of an even order differential operator

abstract:
  Using the method of similar operators we study an even order differential
operator with periodic, semiperiodic, and Dirichlet boundary conditions. We
obtain asymptotic formulas for eigenvalues of this operator and estimates for
its spectral decompositions and spectral projections. We also establish the
asymptotic behavior of the corresponding analytic semigroup of operators.


title: On $Z$-decomposition of some euclidian lie algebras

abstract:
  In this paper we use the $Z-$decomposition as a tool to find locally
symmetric left invariant Riemannian metrics on some Lie groups. For this
purpose, we need to compute the spectrum of the curvature operator. Since the
study of this spectrum is very difficult, we impose restriction on the class of
Riemannian Lie groups and their dimension. We investigate the $4-$dimensional
connected Riemannian Lie groups whose associated Lie algebras are
$\mathbb{A}_2\oplus 2\mathbb{A}_1,\,\mathbb{A}_{3,1}\oplus \mathbb{A}_1,\,
\mathbb{A}_{3,3}\oplus \mathbb{A}_1$ and the subclasses of $3$ and
$4-$dimensional Riemannian Lie groups which are $\mathcal{C}-$spaces.


title: Confidence-Weighted Bipartite Ranking

abstract:
  Bipartite ranking is a fundamental machine learning and data mining problem.
It commonly concerns the maximization of the AUC metric. Recently, a number of
studies have proposed online bipartite ranking algorithms to learn from massive
streams of class-imbalanced data. These methods suggest both linear and
kernel-based bipartite ranking algorithms based on first and second-order
online learning. Unlike kernelized ranker, linear ranker is more scalable
learning algorithm. The existing linear online bipartite ranking algorithms
lack either handling non-separable data or constructing adaptive large margin.
These limitations yield unreliable bipartite ranking performance. In this work,
we propose a linear online confidence-weighted bipartite ranking algorithm
(CBR) that adopts soft confidence-weighted learning. The proposed algorithm
leverages the same properties of soft confidence-weighted learning in a
framework for bipartite ranking. We also develop a diagonal variation of the
proposed confidence-weighted bipartite ranking algorithm to deal with
high-dimensional data by maintaining only the diagonal elements of the
covariance matrix. We empirically evaluate the effectiveness of the proposed
algorithms on several benchmark and high-dimensional datasets. The experimental
results validate the reliability of the proposed algorithms. The results also
show that our algorithms outperform or are at least comparable to the competing
online AUC maximization methods.


title:
A SINFONI view of the nuclear activity and circum-nuclear star formation
  in NGC 4303

abstract:
  We present new maps of emission-line flux distributions and kinematics in
both ionized (traced by HI and [FeII] lines) and molecular (H2) gas of the
inner 0.7x0.7kpc2 of the galaxy NGC4303, with a spatial resolution 40-80pc and
velocity resolution 90-150 km/s obtained from near-IR integral field
specroscopy using the VLT instrument SINFONI. The most promiment feature is a
200-250pc ring of circum-nuclear star-forming regions. The emission from
ionized and molecular gas shows distinct flux distributions: while the
strongest HI and [FeII] emission comes from regions in the west side of the
ring (ages~4Myr), the H2 emission is strongest at the nucleus and in the east
side of the ring (ages>10Myr). We find that regions of enhanced hot H2 emission
are anti-correlated with those of enhanced [FeII] and HI emission, which can be
attributed to post starburst regions that do not have ionizing photons anymore
but still are hot enough (~2000K) to excite the H2 molecule. The line ratios
are consistent with the presence of an AGN at the nucleus.
  The youngest regions have stellar masses in the range 0.3-1.5E5 MSun and
ionized and hot molecular gas masses of ~0.25-1.2E4 Msun and 2.5-5 Msun,
respectively. The stellar and gas velocity fields show a rotation pattern, with
the gas presenting larger velocity amplitudes than the stars, with a deviation
observed for the H2 along the nuclear bar, where increased velocity dispersion
is also observed, possibly associated with non circular motions along the bar.
The stars in the ring show smaller velocity dispersion than the surroundings,
that can be attributed to a cooler dynamics due to their recent formation from
cool gas.


abstract:
  Plyades: A Python Library for Space Mission Design Designing a space mission
is a computation-heavy task. Software tools that conduct the necessary
numerical simulations and optimizations are therefore indispensable. The
usability of existing software, written in Fortran and MATLAB, suffers because
of high complexity, low levels of abstraction and out-dated programming
practices. We propose Python as a viable alternative for astrodynamics tools
and demonstrate the proof-of-concept library Plyades which combines powerful
features with Pythonic ease of use.


title:
Massively parallel implementation in Python of a pseudo-spectral DNS
  code for turbulent flows

abstract:
  Direct Numerical Simulations (DNS) of the Navier Stokes equations is a
valuable research tool in fluid dynamics, but there are very few publicly
available codes and, due to heavy number crunching, codes are usually written
in low-level languages. In this work a \textasciitilde{}100 line standard
scientific Python DNS code is described that nearly matches the performance of
pure C for thousands of processors and billions of unknowns. With optimization
of a few routines in Cython, it is found to match the performance of a more or
less identical solver implemented from scratch in C++. Keys to the efficiency
of the solver are the mesh decomposition and three dimensional FFT routines,
implemented directly in Python using MPI, wrapped through MPI for Python, and a
serial FFT module (both numpy.fft or pyFFTW may be used). Two popular
decomposition strategies, slab and pencil, have been implemented and tested.


title: Unconventional temperature dependence of the cuprate excitation spectrum

abstract:
  Key properties of the cuprates, such as the pseudogap observed above the
critical temperature $T_c$, remain highly debated. Given their importance, we
recently proposed a novel mechanism based on the Bose-like condensation of
mutually interacting Cooper pairs [W. Sacks, A. Mauger, Y. Noat, Superconduct.
Sci. Technol. 28 105014, (2015)]. In this work, we calculate the temperature
dependent DOS using this model for different doping levels from underdoped to
overdoped. In all situations, due to the presence of excited pairs, a pseudogap
is found above $T_c$ while the normal DOS is recovered at $T^*$, the pair
formation temperature. A similar behavior is found as a function of magnetic
field, crossing a vortex, where a pseudogap exists in the vortex core. We show
that the precise DOS shape depends on combined pair (boson) and quasiparticle
(fermion) excitations, allowing for a deeper understanding of the SC to the PG
transition.


title: Spherical Potential Theory: Tools and Applications

abstract:
  This paper provides an overview on tools from potential theory on the sphere
and some applications in geoscience.


title:
Joint User Association and Power Control for Load Balancing in Downlink
  Heterogeneous Cellular Networks

abstract:
  Instead of achievable rate in the conventional association, we utilize the
effective rate to design two association schemes for load balancing in
heterogeneous cellular networks (HCNs), which are both formulated as such
problems with maximizing the sum of effective rates. In these two schemes, the
one just considers user association, but the other introduces power control to
mitigate interference and reduce energy consumption while performing user
association. Since the effective rate is closely related to the load of some BS
and the achievable rate of some user, it can be used as a key factor of
association schemes for load balancing in HCNs. To solve the association
problem without power control, we design a one-layer iterative algorithm, which
converts the sum-of-ratio form of original optimization problem into a
parameterized polynomial form. By combining this algorithm with power control
algorithm, we propose a two-layer iterative algorithm for the association
problem with power control. Specially, the outer layer performs user
association using the algorithm of problem without power control, and the inner
layer updates the transmit power of each BS using a power update function
(PUF). At last, we give some convergence and complexity analyses for the
proposed algorithms. As shown in simulation results, the proposed schemes have
superior performance than the conventional association, and the scheme with
joint user association and power control achieves a higher load balancing gain
and energy efficiency than conventional scheme and other offloading scheme.


title: Lecture Notes on the ARV Algorithm for Sparsest Cut

abstract:
  One of the landmarks in approximation algorithms is the $O(\sqrt{\log
n})$-approximation algorithm for the Uniform Sparsest Cut problem by Arora, Rao
and Vazirani from 2004. The algorithm is based on a semidefinite program that
finds an embedding of the nodes respecting the triangle inequality. Their core
argument shows that a random hyperplane approach will find two large sets of
$\Theta(n)$ many nodes each that have a distance of $\Theta(1/\sqrt{\log n})$
to each other if measured in terms of $\|\cdot \|_2^2$.
  Here we give a detailed set of lecture notes describing the algorithm. For
the proof of the Structure Theorem we use a cleaner argument based on expected
maxima over $k$-neighborhoods that significantly simplifies the analysis.


title:
Fractional diffusion limit of a linear kinetic equation in a bounded
  domain

abstract:
  A version of fractional diffusion on bounded domains, subject to 'homogeneous
Dirichlet boundary conditions' is derived from a kinetic transport model with
homogeneous inflow boundary conditions. For nonconvex domains, the result
differs from standard formulations. It can be interpreted as the forward
Kolmogorow equation of a stochastic process with jumps along straight lines,
remaining inside the domain.


title:
A classification of the natural and social distributions Part 2: the
  explanations

abstract:
  In this second part of our survey on the social and natural distributions, we
investigate some models, which intend to explain the statistical regularity of
the natural and social distributions. There is a large variety of models and in
their majority, they look for a power law, at least in the tail, although there
are several real distributions which are not described by a power law. Among
the power law models, we discuss a) the two basic models and their variants:
the random multiplicative model and the preferential attachment model; b)
models based on the BoseEinstein statistics; c) geographical, economical, and
criticality models. We present also some models, which do not intend to explain
a power law, and among them lognormal-like distributions, exponential and
stretched exponential distributions. The interesting findings of this survey
are that there are few models giving a power law for the complete distribution
and that among them, the Zipf exponent 1 is rare.


title: On the stabilisation height of fibre surfaces in $S^3$

abstract:
  The stabilisation height of a fibre surface in the 3-sphere is the minimal
number of Hopf plumbing operations needed to attain a stable fibre surface from
the initial surface. We show that families of fibre surfaces related by
iterated Stallings twists have unbounded stabilisation height.


title: Embracing Data Science

abstract:
  Statistics is running the risk of appearing irrelevant to today's
undergraduate students. Today's undergraduate students are familiar with data
science projects and they judge statistics against what they have seen.
Statistics, especially at the introductory level, should take inspiration from
data science so that the discipline is not seen as somehow lesser than data
science. This article provides a brief overview of data science, outlines ideas
for how introductory courses could take inspiration from data science, and
provides a reference to materials for developing stand-alone data science
courses.


title: PyCells for an Open Semiconductor Industry

abstract:
  In the modern semiconductor industry, automatic generation of parameterized
and recurring layout structures plays an important role and should be present
as a feature in Electronic Design Automation (EDA)-tools. Currently these
layout generators are developed with a proprietary programming language and can
be used with a specific EDA-tool. Therefore, the semiconductor companies find
the development of the layout generators that can be used in all state of the
art EDA-tools which support OpenAccess database appealing. The goal of this
project is to develop computationally efficient layout generators with Python
(PyCells), for ams AG technologies, that possess all the features of
comprehensive layout generators.


title:
Contradictions and narrowness of views in "The fables of Ishango, or the
  irresistible temptation of mathematical fiction", answers and updates (in
  English and in French)

abstract:
  We answer to criticisms of O. Keller about our interpretation work on the
Ishango rod, the oldest mathematical tool of humankind. Our hypothesis, that is
widely accepted, is that this prehistoric rod is the first mankind
manifestation of a basic arithmetic intention, with simple arithmetic
operations and possibly showing passages between 10 and 12 bases.


title: $\lambda$-persistant CSMA: a radio-channel access protocol

abstract:
  This paper presents an algorithm that improves channel-access statistics for
wireless medium. The proposed modification of the standard CSMA algorithm is
analytically shown to yield better results and simulation results are given to
support this claim.


title: One- and Multi-Pass Long-Hop Routing for Wireless Network

abstract:
  In our paper we provide mathematical analysis of a probabilistic long-hop
routing algorithms which uses as the randomizing factor the estimate of
distance of a station from the previous-hop source of the message.


title:
A Jamming-Resilient MAC-layer Device Identification for Internet of
  Things

abstract:
  In a number of practical scenarios a wireless device needs to mark its
presence, for instance, to some access point. That enables the access point to
assign the device its transmission slot or update the count of the network
nodes. Many protocols can achieve exactly this result. In this paper, our goal
is to show how that can be done in the simplest messaging model, the so-called
beeping model. Consequently, we constrain our design so that the station does
not send any modulated information in the signal and the receiver actually does
not need to demodulate/decode it. We are interested in sending just a short
signal, so called 'beep'. Moreover, we want to design such protocol that is
resilient to random interference and enables us to identify devices which are
sending the signal, as opposed to only note their presence. To do that, we
leverage temporal correlations of a sequence of beeps issued by a device, as if
the time-moments when they happen come from a pre-defined probability
distribution, that is the fingerpring of the device.


title: A tutorial on estimator averaging in spatial point process models

abstract:
  Assume that several competing methods are available to estimate a parameter
in a given statistical model. The aim of estimator averaging is to provide a
new estimator, built as a linear combination of the initial estimators, that
achieves better properties, under the quadratic loss, than each individual
initial estimator. This contribution provides an accessible and clear overview
of the method, and investigates its performances on standard spatial point
process models. It is demonstrated that the average estimator clearly improves
on standard procedures for the considered models. For each example, the code to
implement the method with the R software (which only consists of few lines) is
provided.


title: Low-energy microscopic models for iron-based superconductors: a review

abstract:
  The development of sensible microscopic models is essential to elucidate the
normal-state and superconducting properties of the iron-based superconductors.
Because these materials are mostly metallic, a good starting point is an
effective low-energy model that captures the electronic states near the Fermi
level and their interactions. However, in contrast to cuprates, iron-based
high-$T_{c}$ compounds are multi-orbital systems with Hubbard and Hund
interactions, resulting in a rather involved 10-orbital lattice model. Here we
review different minimal models that have been proposed to unveil the universal
features of these systems. We first review minimal models defined solely in the
orbital basis, which focus on a particular subspace of orbitals, or solely in
the band basis, which rely only on the geometry of the Fermi surface. The
former, while providing important qualitative insight into the role of the
orbital degrees of freedom, do not distinguish between high-energy and
low-energy sectors and, for this reason, generally do not go beyond mean-field.
The latter allow one to go beyond mean-field and investigate the interplay
between superconducting and magnetic orders as well as Ising-nematic order.
However, they cannot capture orbital-dependent features like spontaneous
orbital order. We then review recent proposals for a minimal model that
operates in the band basis but fully incorporates the orbital composition and
symmetries of the low-energy excitations. We discuss the results of the
renormalization group study of such a model, particularly of the interplay
between superconductivity, magnetism, and spontaneous orbital order, and
compare theoretical predictions with experiments on iron pnictides and
chalcogenides. We also discuss the impact of the glide-plane symmetry on the
low-energy models, highlighting the key role played by the spin-orbit coupling.


title: The Primal versus the Dual Ising Model

abstract:
  We represent the Ising model of statistical physics by normal factor graphs
in the primal and in the dual domains. By analogy with Kirchhoff's voltage and
current laws, we show that in the primal normal factor graphs, the dependency
among the variables is along the cycles, whereas in the dual normal factor
graphs, the dependency is on the cutsets. In the primal (resp. dual) domain,
dependent variables can be computed via their fundamental cycles (resp.
fundamental cutsets). Using Onsager's closed form solution, we illustrate the
opposite behavior of the uniform sampling estimator for estimating the
partition function in the primal and in the dual of the homogeneous Ising model
on a two-dimensional torus.


title:
Analytic inversion of a conical Radon transform arising in application
  of Compton cameras on the cylinder

abstract:
  Single photon emission computed tomography (SPECT) is a well established
clinical tool for functional imaging. A limitation of current SPECT systems is
the use of mechanical collimation, where only a small fraction of the emitted
photons is actually used for image reconstruction. This results in large noise
level and finally in a limited spatial resolution. In order to decrease the
noise level and to increase the imaging resolution, Compton cameras have been
proposed as an alternative to mechanical collimators. Image reconstruction in
SPECT with Compton cameras yields to the problem of recovering a marker
distribution from integrals over conical surfaces. Due to this and other
applications, such conical Radon transforms recently got significant attention.
In the current paper we consider the case where the cones of integration have
vertices on a circular cylinder and axis pointing to the symmetry axis of the
cylinder. As main results we derive analytic reconstruction methods for the
considered transform. We also investigate the V-line transform with vertices on
a circle and symmetry axis orthogonal to the circle, which arises in the
special case where the absorber distribution is located in a horizontal plane.


title:
New error measures and methods for realizing protein graphs from
  distance data

abstract:
  The interval Distance Geometry Problem (iDGP) consists in finding a
realization in $\mathbb{R}^K$ of a simple undirected graph $G=(V,E)$ with
nonnegative intervals assigned to the edges in such a way that, for each edge,
the Euclidean distance between the realization of the adjacent vertices is
within the edge interval bounds. In this paper, we focus on the application to
the conformation of proteins in space, which is a basic step in determining
protein function: given interval estimations of some of the inter-atomic
distances, find their shape. Among different families of methods for
accomplishing this task, we look at mathematical programming based methods,
which are well suited for dealing with intervals. The basic question we want to
answer is: what is the best such method for the problem? The most meaningful
error measure for evaluating solution quality is the coordinate root mean
square deviation. We first introduce a new error measure which addresses a
particular feature of protein backbones, i.e. many partial reflections also
yield acceptable backbones. We then present a set of new and existing quadratic
and semidefinite programming formulations of this problem, and a set of new and
existing methods for solving these formulations. Finally, we perform a
computational evaluation of all the feasible solver$+$formulation combinations
according to new and existing error measures, finding that the best methodology
is a new heuristic method based on multiplicative weights updates.