title: Invasive competition with Fokker-Planck diffusion and noise

abstract:
  Defeat and success of the competitive invasion of a populated area is
described with a standard Lotka-Volterra competition model. The resident is
adapted to the heterogeneous living conditions, i.e., its motion is modelled as
space-dependent, so-called Fokker-Planck diffusion. The invader's diffusion is
taken as neutral Fickian. Furthermore, it is studied how multiplicative
environmental noise fosters or hinders the invasion.


title:
CNO behaviour in planet-harbouring stars. II. Carbon abundances in stars
  with and without planets using the CH band

abstract:
  Context. Carbon, oxygen and nitrogen (CNO) are key elements in stellar
formation and evolution, and their abundances should also have a significant
impact on planetary formation and evolution.
  Aims. We present a detailed spectroscopic analysis of 1110 solar-type stars,
143 of which are known to have planetary companions. We have determined the
carbon abundances of these stars and investigate a possible connection between
C and the presence of planetary companions. Methods. We used the HARPS
spectrograph to obtain high-resolution optical spectra of our targets. Spectral
synthesis of the CH band at 4300\AA was performed with the spectral synthesis
codes MOOG and FITTING.
  Results. We have studied carbon in several reliable spectral windows and have
obtained abundances and distributions that show that planet host stars are
carbon rich when compared to single stars, a signature caused by the known
metal-rich nature of stars with planets. We find no different behaviour when
separating the stars by the mass of the planetary companion.
  Conclusions. We conclude that reliable carbon abundances can be derived for
solar-type stars from the CH band at 4300\AA. We confirm two different slope
trends for [C/Fe] with [Fe/H] because the behaviour is opposite for stars above
and below solar values. We observe a flat distribution of the [C/Fe] ratio for
all planetary masses, a finding that apparently excludes any clear connection
between the [C/Fe] abundance ratio and planetary mass.


title: On products of Groups with abelian subgroups of small index

abstract:
  It is proved that every group of the form $G=AB$ with two subgroups $A$ and
$B$ each of which is either abelian or has a quasicyclic subgroup of index $2$
is soluble of derived length at most $3$. In particular, if $A$ is abelian and
$B$ is a locally quaternion group, this gives a positive answer to Question
18.95 of "Kourovka notebook" posed by A.I.Sozutov.


title: The influence of the network topology on the agility of a supply chain

abstract:
  The right performance of a supply chain depends on the pattern of
relationships among firms. Although there is not a general consensus among
researchers yet, many studies point that scale-free topologies, where few
highly related firms are combined with many low-related firms, assure the
highest efficiency of a supply chain. This paper studies the network topology
that leads to the highest agility of the supply chain when sudden demand
changes occur. To do this, an agent-based model of a supply chain with
restricted relationship between agents is built. The model includes three
tiers, where the flow of material is distributed from the bottom supplier to
the final customer passing necessarily through firms in every tier. Agility is
measured in the model simulations through the order fulfillment rate. Unlike to
previous theoretical and lab results, the simulation of the model shows that
the highest levels of agility are not obtained with a scale-free topology.
Instead, homogeneous distribution of links, such as those induced by regular or
Poisson probability laws, shows higher agility values than heterogeneous
distributions. Other previous recommendations, such as redundancy or having
multiple suppliers, are confirmed by the simulations. The general conclusion is
that the most suitable network topology in terms of agility depends on the
specific conditions of the supply chain and the aspects of the performance to
be analyzed.


title: System-Generated Requests for Rewriting Proposals

abstract:
  We present an online deliberation system using mutual evaluation in order to
collaboratively develop solutions. Participants submit their proposals and
evaluate each other's proposals; some of them may then be invited by the system
to rewrite 'problematic' proposals. Two cases are discussed: a proposal
supported by many, but not by a given person, who is then invited to rewrite it
for making yet more acceptable; and a poorly presented but presumably
interesting proposal. The first of these cases has been successfully
implemented. Proposals are evaluated along two axes-understandability (or
clarity, or, more generally, quality), and agreement. The latter is used by the
system to cluster proposals according to their ideas, while the former is used
both to present the best proposals on top of their clusters, and to find poorly
written proposals candidates for rewriting. These functionalities may be
considered as important components of a large scale online deliberation system.


title: Two Dimensional F(R) Horava-Lifshitz Gravity

abstract:
  We study two-dimensional F(R) Horava-Lifshitz gravity from the Hamiltonian
point of view. We determine constraints structure with emphasis on the careful
separation of the second class constraints and global first class constraints.
We determine number of physical degrees of freedom and also discuss gauge
fixing of the global first class constraints.


title:
Ontologies for Privacy Requirements Engineering: A Systematic Literature
  Review

abstract:
  Privacy has been frequently identified as a main concern for system
developers while dealing with/managing personal information. Despite this, most
existing work on privacy requirements deals with them as a special case of
security requirements. Therefore, key aspects of privacy are, usually,
overlooked. In this context, wrong design decisions might be made due to
insufficient understanding of privacy concerns. In this paper, we address this
problem with a systematic literature review whose main purpose is to identify
the main concepts/relations for capturing privacy requirements. In addition,
the identified concepts/relations are further analyzed to propose a novel
privacy ontology to be used by software engineers when dealing with privacy
requirements.


title: Tunable edge states and their robustness towards disorder

abstract:
  The interest in the properties of edge states in Chern insulators and in
$\mathbb{Z}_2$ topological insulator has increased rapidly in recent years. We
present calculations on how to influence the transport properties of chiral and
helical edge states by modifications of the edges in the Haldane and in the
Kane-Mele model. The Fermi velocity of the chiral edge states becomes
direction-dependent as does the spin-dependent Fermi velocity of the helical
edge states. Moreover, it is possible to tune the Fermi velocity by orders of
magnitude. Additionally, we explicitly investigate the robustness of edge
states against local disorder. The edge states can be reconstructed in the
Brillouin zone in presence of disorder. The influence of the width and of the
length of the system is studied as well as the dependence on the strength of
the disorder.


title: Stability of the entropy equation

abstract:
  In this paper we prove that the so--called entropy equation, i.e., \[
H\left(x, y, z\right)=H\left(x+y, 0, z\right)+H\left(x, y, 0\right) \] is
stable in the sense of Hyers and Ulam on the positive cone of $\mathbb{R}^{3}$,
assuming that the function $H$ is approximatively symmetric in each variable
and approximatively homogeneous of degree $\alpha$, where $\alpha$ is an
arbitrarily fixed real number.


title:
Dipole model analysis of highest precision HERA data, including very low
  $Q^2$'s

abstract:
  We analyse, within a dipole model, the final, inclusive HERA DIS cross
section data in the low $x$ region, using fully correlated errors. We show,
that these highest precision data are very well described within the dipole
model framework starting from $Q^2$ values of 3.5 GeV$^2$ to the highest values
of $Q^2 =$ 250 GeV$^2$.


title: Projective Automorphism Groups of Nonsingular Quartic Surfaces

abstract:
  For every p >= 5, we determine all Z_p-invariant nonsingular quartic surfaces
in the three dimensional projective space over an algebraically closed field of
characteristic zero. In some cases, we also determine their full projective
automorphism groups.


title: Coherence and aberration effects in surface plasmon polariton imaging

abstract:
  We study theoretically and experimentally coherent imaging of surface plasmon
polaritons using either leakage radiation microscopy through a thin metal film
or interference microscopy through a thick metal film. Using a rigorous modal
formalism based on scalar Whittaker potentials we develop a systematic
analytical and vectorial method adapted to the analysis of coherent imaging
involving surface plasmon polaritons. The study includes geometrical
aberrations due index mismatch which played an important role in the
interpretation of recent experiments using leakage radiation microscopy. We
compare our theory with experiments using classical or quantum near-field
scanning optical microscopy probes and show that the approach leads to a full
interpretation of the recorded optical images.


title:
Explicit counting of ideals and a Brun-Titchmarsh inequality for the
  Chebotarev Density Theorem

abstract:
  We prove a bound on the number of primes with a given splitting behaviour in
a given field extension. This bound generalises the Brun-Titchmarsh bound on
the number of primes in an arithmetic progression. The proof is set up as an
application of Selberg's Sieve in number fields. The main new ingredient is an
explicit counting result estimating the number of integral elements with
certain properties up to multiplication by units. As a consequence of this
result, we deduce an explicit estimate for the number of ideals of norm up to
$x$.


title: User Dependent Features in Online Signature Verification

abstract:
  In this paper, we propose a novel approach for verification of on-line
signatures based on user dependent feature selection and symbolic
representation. Unlike other signature verification methods, which work with
same features for all users, the proposed approach introduces the concept of
user dependent features. It exploits the typicality of each and every user to
select different features for different users. Initially all possible features
are extracted for all users and a method of feature selection is employed for
selecting user dependent features. The selected features are clustered using
Fuzzy C means algorithm. In order to preserve the intra-class variation within
each user, we recommend to represent each cluster in the form of an interval
valued symbolic feature vector. A method of signature verification based on the
proposed cluster based symbolic representation is also presented. Extensive
experimentations are conducted on MCYT-100 User (DB1) and MCYT-330 User (DB2)
online signature data sets to demonstrate the effectiveness of the proposed
novel approach.


title: Improvement of flatness for nonlocal phase transitions

abstract:
  We prove an improvement of flatness result for nonlocal phase transitions.
For a class of nonlocal equations that includes $(-\Delta)^{s/2} u = u-u^3$,
with~$s\in(0,1)$, we obtain a result in the same spirit of a celebrated theorem
of Savin for the equation $-\Delta u = u-u^3$. As a consequence, we deduce that
entire solutions to~$(-\Delta)^{s/2} u = u-u^3$ with asymptotically flat level
sets are $1$D when~$s\in(0,1)$.
  The results presented are completely new even for the case of the fractional
Laplacian, but the robustness of the proofs allows us to treat also more
general, possibly anisotropic, integro-differential operators.


title: Stability in the class of first order delay differential equations

abstract:
  The main aim of this paper is the investigation of the stability problem for
ordinary delay differential equations. More precisely, we would like to study
the following problem. Assume that for a continuous function a given delay
differential equation is fulfilled only approximately. Is it true that in this
case this function is close to an exact solution of this delay differential
equation?


title:
Private quantum computation: An introduction to blind quantum computing
  and related protocols

abstract:
  Quantum technologies hold the promise of not only faster algorithmic
processing of data, via quantum computation, but also of more secure
communications, in the form of quantum cryptography. In recent years, a number
of protocols have emerged which seek to marry these concepts for the purpose of
securing computation rather than communication. These protocols address the
task of securely delegating quantum computation to an untrusted device while
maintaining the privacy, and in some instances the integrity, of the
computation. We present a review of the progress to date in this emerging area.


title:
Directional and singular surface plasmon generation in chiral and
  achiral nanostructures demonstrated by Leakage Radiation Microscopy

abstract:
  In this paper, we describe the implementation of leakage radiation microscopy
(LRM) to probe the chirality of plasmonic nanostructures. We demonstrate
experimentally spin-driven directional coupling as well as vortex generation of
surface plasmon polaritons (SPPs) by nanostructures built with T-shaped and
$\Lambda$- shaped apertures. Using this far-field method, quantitative
inspections, including directivity and extinction ratio measurements, are
achieved via polarization analysis in both image and Fourier planes. To support
our experimental findings, we develop an analytical model based on a
multidipolar representation of $\Lambda$- and T-shaped aperture plasmonic
coupler allowing a theoretical explanation of both directionality and singular
SPP formation. Furthermore, the roles of symmetry breaking and phases are
emphasized in this work. This quantitative characterization of spin-orbit
interactions paves the way for developing new directional couplers for
subwavelength routing.


title:
Generation of femtosecond optical vortex beams in all-fiber mode-locked
  fiber laser using mode selective coupler

abstract:
  We experimentally demonstrated a high-order optical vortex pulsed laser based
on a mode selective all-fiber fused coupler composed of a single-mode fiber
(SMF) and a few-mode fiber (FMF). The fused SMF-FMF coupler inserted in the
cavity not only acts as mode converter from LP01 mode to LP11 or LP21 modes
with a broadband width over 100 nm, but also directly delivers femtosecond
vortex pulses out of the mode locked cavity. To the best of our knowledge, this
is the first report on the generation of high-order pulse vortex beams in
mode-locked fiber laser. The generated 140 femtosecond vortex beam has a
spectral width of 67 nm centered at 1544 nm.


title:
Groupes $p$-divisibles avec condition de Pappas-Rapoport et invariants
  de Hasse

abstract:
  We study $p$-divisible groups $G$ endowed with an action of the ring of
integers of a finite (possibly ramified) extension of $\mathbb{Q}_p$ over a
scheme of characteristic $p$. We suppose moreover that the $p$-divisible group
$G$ satisfies the Pappas-Rapoport condition for a certain datum $\mu$ ; this
condition consists in a filtration on the sheaf of differentials $\omega_G$
satisfying certain properties. Over a perfect field, we define the Hodge and
Newton polygons for such $p$-divisible groups, normalized with the action. We
show that the Newton polygon lies above the Hodge polygon, itself lying above a
certain polygon depending on the datum $\mu$. We then construct Hasse
invariants for such $p$-divisible groups over an arbitrary base scheme of
characteristic $p$. We prove that the total Hasse invariant is non-zero if and
only if the $p$-divisible group is $\mu$-ordinary, i.e. if its Newton polygon
is minimal. Finally, we study the properties of $\mu$-ordinary $p$-divisible
groups. The construction of the Hasse invariants can in particular be applied
to special fibers of PEL Shimura varieties models as constructed by Pappas and
Rapoport.


title: The dimension of irregular set in parameter space

abstract:
  For any real number $\beta>1$. The $n$th cylinder of $\beta$ in the parameter
space $\{\beta\in \mathbb{R}: \beta>1\}$ is a set of real numbers in
$(1,\infty)$ having the same first $n$ digits in their $\beta$-expansion of
$1$, denote by $I^P_n(\beta)$. We study the quantities which describe the
growth of the length of $I^P_n(\beta)$. The Huasdorff dimension of the set of
given growth rate of the length of $I^P_n(\beta)$ will be determined in this
paper.


title: Online Production Validation in a HEP environment

abstract:
  Petabytes of data are to be processed and stored requiring millions of
CPU-years in high energy particle (HEP) physics event simulation. This enormous
demand is handled in worldwide distributed computing centers as part of the LHC
computing grid. These significant resources require a high quality and
efficient production and the early detection of potential errors. In this
article we present novel monitoring techniques in a Grid environment to collect
quality measures during job execution. This allows online assessment of data
quality information to avoid configuration errors or inappropriate settings of
simulation parameters and therefore is able to save time and resources.


title: Precision calculation of energy levels for four-valent Si I

abstract:
  We report results of the calculation of the low-lying levels of neutral Si
using a combination of the configuration interaction and many-body perturbation
theory (CI+MBPT method). We treat Si I as an atom with four valence electrons
and use two different starting approximations, namely $V^{N-2}$ and $V^{N-4}$.
We conclude that both approximations provide comparable accuracy, on the level
of 1%.


title: Nonlinear Waves

abstract:
  A method for solving a quasilinear nonelliptical equation of the second order
is developed and we give classification and parametrization of simple elements
of the equation.We find exact solutions of an equation for potential stationary
flow of a compressible gas in a supersonic region as an example of the method.


title:
Highly efficient singular surface plasmon generation by achiral
  apertures

abstract:
  We report a highly efficient generation of singular surface plasmon (SP)
field by an achiral plasmonic structure consisting of $\Lambda$-shaped
apertures. Our quantitative analysis based on leakage radiation microscopy
(LRM) demonstrates that the induced spin-orbit coupling can be tuned by
adjusting the apex angle of the $\Lambda$-shaped aperture. Specifically, the
array of $\Lambda$-shaped apertures with the apex angle $60^\circ$ is shown to
give rise to the directional coupling efficiency. The ring of $\Lambda$-shaped
apertures with the apex angle $60^\circ$ realized to generate the maximum
extinction ratio (ER=11) for the SP singularities between two different
polarization states. This result provides a more efficient way for developing
SP focusing and SP vortex in the field of nanophotonics such as optical
tweezers.


title: Algebraic volumes of divisors

abstract:
  The volume of a Cartier divisor on a projective variety is a nonnegative real
number that measures the asymptotic growth of sections of multiples of the
divisor. It is known that the set of these numbers is countable and has the
structure of a multiplicative semigroup. At the same time it still remains
unknown which nonnegative real algebraic numbers arise as volumes of Cartier
divisors on some variety. Here we extend a construction first used by Cutkosky,
and use the theory of real multiplication on abelian varieties to obtain a
large class of examples of algebraic volumes. We also show that $\pi$ arises as
a volume.


title: On the binomial edge ideals of proper interval graphs

abstract:
  We prove several cases of the Betti number conjecture for the binomial edge
ideal $J_G$ of a proper interval graph $G$ (also known as closed graph).
Namely, we show that this conjecture is true for the linear strand of $J_G$,
and true in general for any proper interval graph $G$ such that the regularity
of $S/J_G$ equals two.


title: More about the light baryon spectrum

abstract:
  We discuss the light baryon spectrum obtained from a recent quark-diquark
calculation, implementing non-pointlike diquarks that are self-consistently
calculated from their Bethe-Salpeter equations. We examine the orbital angular
momentum content in the baryons' rest frame and highlight the fact that baryons
carry all possible values of L compatible with their spin, without the
restriction P=(-1)^L which is only valid nonrelativistically. We furthermore
investigate the meaning of complex conjugate eigenvalues of Bethe-Salpeter
equations, their possible connection with 'anomalous' states, and we propose a
method to eliminate them from the spectrum.


title:
A dual-Lagrangian description adapted to quantum optics in dispersive
  and dissipative dielectric media

abstract:
  We develop a dual description of quantum optics adapted to dielectric systems
without magnetic property. Our formalism, which is shown to be equivalent to
the standard one within some dipolar approximations discussed in the article,
is applied to the description of polaritons in dielectric media. We show that
the dual formalism leads to the Huttner-Barnett equations [B. Huttner, S. M.
Barnett, Phys. Rev. A \textbf{46}, 4306 (1992)] for QED in dielectric systems.
More generally, we discuss the role of electromagnetic duality in the
quantization procedure for optical systems and derive the structure of the
dynamical laws in the various representations.


title:
Fusion of EEG and Musical Features in Continuous Music-emotion
  Recognition

abstract:
  Emotion estimation in music listening is confronting challenges to capture
the emotion variation of listeners. Recent years have witnessed attempts to
exploit multimodality fusing information from musical contents and
physiological signals captured from listeners to improve the performance of
emotion recognition. In this paper, we present a study of fusion of signals of
electroencephalogram (EEG), a tool to capture brainwaves at a high-temporal
resolution, and musical features at decision level in recognizing the
time-varying binary classes of arousal and valence. Our empirical results
showed that the fusion could outperform the performance of emotion recognition
using only EEG modality that was suffered from inter-subject variability, and
this suggested the promise of multimodal fusion in improving the accuracy of
music-emotion recognition.


title: Crossed-products by locally compact groups: Intermediate subfactors

abstract:
  We study actions of locally compact groups on von Neumann factors and the
associated crossed-product von Neumann algebras. In the setting of totally
disconnected groups we provide sufficient conditions on an action
$G\curvearrowright Q$ ensuring that the inclusion $Q \subset Q \rtimes G$ is
irreducible and that every intermediate subfactor is of the form $Q \rtimes H$
for a closed subgroup $H<G$. This partially generalizes a result of
Izumi-Longo-Popa [ILP98] and Choda [Ch78]. We moreover show that one can not
hope to use their strategy for non-discrete groups.


title: Deep encoding of etymological information in TEI

abstract:
  This paper aims to provide a comprehensive modeling and representation of
etymological data in digital dictionaries. The purpose is to integrate in one
coherent framework both digital representations of legacy dictionaries, and
also born-digital lexical databases that are constructed manually or
semi-automatically. We want to propose a systematic and coherent set of
modeling principles for a variety of etymological phenomena that may contribute
to the creation of a continuum between existing and future lexical constructs,
where anyone interested in tracing the history of words and their meanings will
be able to seamlessly query lexical resources.Instead of designing an ad hoc
model and representation language for digital etymological data, we will focus
on identifying all the possibilities offered by the TEI guidelines for the
representation of lexical information.


title: Low-temperature thermometry can be enhanced by strong coupling

abstract:
  We consider the problem of estimating the temperature $ T $ of a very cold
equilibrium sample. The temperature estimates are drawn from measurements
performed on a quantum probe strongly coupled to it. We model this scenario by
resorting to the canonical Caldeira-Leggett Hamiltonian and find analytically
the exact stationary state of the probe for arbitrary coupling strength. In
general, the probe does not reach thermal equilibrium with the sample, due to
their non-perturbative interaction. We argue that this is advantageous for low
temperature thermometry, as we show in our model that: (i) The thermometric
precision at low $ T $ can be significantly enhanced by strengthening the
probe-sampling coupling, (ii) the variance of a suitable quadrature of our
Brownian thermometer can yield temperature estimates with nearly minimal
statistical uncertainty, and (iii) the spectral density of the probe-sample
coupling may be engineered to further improve thermometric performance. These
observations may find applications in practical nanoscale thermometry at low
temperatures---a regime which is particularly relevant to quantum technologies.


title: On the first eigenvalue for a (p(x),q(x))-Laplacian elliptic system

abstract:
  In this article, we deal about the first eigenvalue for a nonlinear gradient
type elliptic system involving variable exponents growth conditions.
Positivity, boundedness and regularity of associated eigenfunctions for
auxiliaries systems are established.


title:
Constraints on violation of Lorentz invariance from atmospheric showers
  initiated by multi-TeV photons

abstract:
  We discuss the effect of hypothetical violation of Lorentz invariance at high
energies on the formation of atmospheric showers by very-high-energy gamma
rays. In the scenario where Lorentz invariance violation leads to a decrease of
the photon velocity with energy the formation of the showers is suppressed
compared to the Lorentz invariant case. Absence of such suppression in the
high-energy part of spectrum of the Crab nebula measured independently by HEGRA
and H.E.S.S. collaborations is used to set lower bounds on the energy scale of
Lorentz invariance violation. These bounds are competitive with the strongest
existing constraints obtained from timing of variable astrophysical sources and
the absorption of TeV photons on the extragalactic background light. They will
be further improved by the next generation of multi-TeV gamma-ray
observatories.


title:
Novel Kondo-like behavior near magnetic instability in SmB$_6$ :
  temperature and pressure dependences of Sm valence

abstract:
  We report a systematic study of Sm valence in the prototypical intermediate
valence compound SmB$_6$. Sm mean valence, $v_{\rm Sm}$, was measured by X-ray
absorption spectroscopy as functions of pressure ($1<P<13$ GPa) and temperature
($3<T<300$ K). Pressure induced magnetic order (MO) was detected above $P_c =
10$ GPa by resistivity measurements. A shift toward localized $4f$ state with
increasing $P$ and/or $T$ is evident from an increase in $v_{\rm Sm}$. However
$v_{\rm Sm}$ at $P_c$ is anomalously far below 3, which differs from the
general case of nonmagnetic-magnetic transition in Yb and Ce compounds. From
the $T$ dependence of $v_{\rm Sm}(P,T)$, we found that $v_{\rm Sm}(P,T)$
consists of two different characteristic components: one is associated with
low-energy electronic correlations involving Kondo like behavior, and the other
with high-energy valence fluctuations.


title:
Effect of Strontium substitution on the structural and magnetic
  properties of La1.8Sr0.2MMnO6 (M = Ni, Co) layered manganites

abstract:
  Sr substituted perovskites La1.8Sr0.2MMnO6 (M = Ni, Co) were synthesized
using solid state reaction technique to present a systematic study on their
morphological, structural and magnetic properties. The average grain size of
the as-prepared La1.8Sr0.2NiMnO6 samples are in the range of 0.2-0.7 {\mu}m and
those for La1.8Sr0.2CoMnO6 manganites are 0.1-2.8 {\mu}m, which is
significantly less than that of unsubstituted La2NiMnO6 (LNMO) and La2CoMnO6
(LCMO) manganites. The XPS analysis enlightened about phase purity, binding
energy and oxygen vacancy of La1.8Sr0.2MMnO6 manganites. The Sr substituted
LNMO has revealed a sharp ferromagnetic to paramagnetic phase transition at 160
K which is about 120 K less than that of parent LNMO. The Sr substituted LCMO
exhibited such a transition at 220 K which is 8 K less than that of parent
LCMO. The temperature dependent magnetization measurements suggest that the
effect of Sr on the transition temperature in LNMO is more significant than
that of LCMO.


title:
Study of a sealed high gas pressure THGEM detector and response of Alpha
  particle spectra

abstract:
  A sealed high gas pressure detector working in pure argon is assembled. It
consists of a 5 cm $\times$ 5 cm PCB THGEM (THick Gaseous Electron
Multipliers). The detector structure and experimental setup are described. The
performances under high pressure of 2 atm mainly consist in selecting optimal
voltages for ionization region and induction region. The dependence of the
shape of Alpha particle spectra measured with relative gas gain on gas pressure
(1.3 $\sim$ 2.0 atm) has been studied. The 8 groups of relative gas gain versus
working voltage of THGEM expressed by weighting filed $E/P$ are normalized,
being consistent with theory. The results show that the air tightness of the
chamber is good measured by a sensitive barometer and checked with gas gain.
The experimental results are compared with Monte Carlo simulation on energy
deposition without gas gain involved.


title:
On measures of accretion and dissipation for solutions of the
  Camassa-Holm equation

abstract:
  We investigate the measures of dissipation and accretion related to the weak
solutions of the Camassa-Holm equation. Demonstrating certain properties of
nonunique characteristics, we prove a new representation formula for these
measures and conclude about their structural features, such us singularity with
respect to the Lebesgue measure. We apply these results to gain new insights
into the structure of weak solutions, proving in particular that measures of
accretion vanish for dissipative solutions of the Camassa-Holm equation.


title:
ADMM-based Fast Algorithm for Multi-group Multicast Beamforming in
  Large-Scale Wireless Systems

abstract:
  Multi-group multicast beamforming in wireless systems with large antenna
arrays and massive audience is investigated in this paper. Multicast
beamforming design is a well-known non-convex quadratically constrained
quadratic programming (QCQP) problem. A conventional method to tackle this
problem is to approximate it as a semi-definite programming problem via
semi-definite relaxation, whose performance, however, deteriorates considerably
as the number of per-group users goes large. A recent attempt is to apply
convex-concave procedure (CCP) to find a stationary solution by treating it as
a difference of convex programming problem, whose complexity, however,
increases dramatically as the problem size increases. In this paper, we propose
a low-complexity high-performance algorithm for multi-group multicast
beamforming design in large-scale wireless systems by leveraging the
alternating direction method of multipliers (ADMM) together with CCP. In
specific, the original non-convex QCQP problem is first approximated as a
sequence of convex subproblems via CCP. Each convex subproblem is then
reformulated as a novel ADMM form. Our ADMM reformulation enables that each
updating step is performed by solving multiple small-size subproblems with
closed-form solutions in parallel. Numerical results show that our fast
algorithm maintains the same favorable performance as state-of-the-art
algorithms but reduces the complexity by orders of magnitude.


title:
Mean Flow Evolution of Saturated Forced Shear Flows in Polytropic
  Atmospheres

abstract:
  In stellar interiors shear flows play an important role in many physical
processes. So far helioseismology provides only large-scale measurements, and
so the small-scale dynamics remains insufficiently understood. To draw a
connection between observations and three-dimensional DNS of shear driven
turbulence, we investigate horizontally averaged profiles of the numerically
obtained mean state. We focus here on just one of the possible methods that can
maintain a shear flow, namely the average relaxation method. We show that
although some systems saturate by restoring linear marginal stability this is
not a general trend. Finally, we discuss the reason that the results are more
complex than expected.


title:
Measurements and TCAD Simulations of Bulk and Surface Radiation Damage
  Effects in Silicon Detectors

abstract:
  In this work we propose the application of a radiation damage model based on
the introduction of deep level traps/recombination centers suitable for device
level numerical simulation of radiation detectors at very high fluences (e.g.
1{\div}2 10^16 1-MeV equivalent neutrons per square centimeter) combined with a
surface damage model developed by using experimental parameters extracted from
measurements from gamma irradiated p-type dedicated test structures.


title: Rounds in a combinatorial search problem

abstract:
  We consider the following combinatorial search problem: we are given some
excellent elements of $[n]$ and we should find at least one, asking questions
of the following type: "Is there an excellent element in $A \subset [n]$?".
G.O.H. Katona proved sharp results for the number of questions needed to ask in
the adaptive, non-adaptive and two-round versions of this problem.
  We verify a conjecture of Katona by proving that in the $r$-round version we
need to ask $rn^{1/r}+O(1)$ queries for fixed $r$ and this is sharp.
  We also prove bounds for the queries needed to ask if we want to find at
least $d$ excellent elements.


title: Modules over the de Rham cohomology spectrum

abstract:
  We show that the bounded derived category of regular holonomic D-modules on a
smooth variety is equivalent to the homotopy catgory of compact (or
constructible) modules over the motivic ring spectrum $H_{dR}$ representing
algebraic de Rham cohomology. This equivalence is compatible with the six
functors on both sides. This way, the classical functors in the world of
D-modules, $f_! := D_Y f_* D_X, f^* := D_X f^! D_Y$ ($f: X \to Y$), are
conceptually explained and embedded into a larger and more flexible framework.
We also apply this equivalence to obtain a motivic t-structure on
$H_{dR}$-modules on not necessarily smooth schemes.


title:
Preserving coherent spin and squeezed spin states of a spin-1
  Bose-Einstein condensate with rotary echoes

abstract:
  A challenge in precision measurement with squeezed spin state arises from the
spin dephasing due to stray magnetic fields. To suppress such environmental
noises, we employ a continuous driving protocol, rotary echo, to enhance the
spin coherence of a spin-1 Bose-Einstein condensate in stray magnetic fields.
Our analytical and numerical results show that the coherent and the squeezed
spin states are preserved for a significantly long time, compared to the free
induction decay time, if the condition $h\tau = m\pi$ is met with $h$ the pulse
amplitude and $\tau$ pulse width. In particular, both the spin average and the
spin squeezing, including the direction and the amplitude, are simultaneously
fixed for a squeezed spin state. Our results point out a practical way to
implement quantum measurements based on a spin-1 condensate beyond the standard
quantum limit.


title: Iterative Methods for Sparse Signal Reconstruction from Level Crossings

abstract:
  This letter considers the problem of sparse signal reconstruction from the
timing of its Level Crossings (LC)s. We formulate the sparse Zero Crossing (ZC)
reconstruction problem in terms of a single 1-bit Compressive Sensing (CS)
model. We also extend the Smoothed L0 (SL0) sparse reconstruction algorithm to
the 1-bit CS framework and propose the Binary SL0 (BSL0) algorithm for
iterative reconstruction of the sparse signal from ZCs in cases where the
number of sparse coefficients is not known to the reconstruction algorithm a
priori. Similar to the ZC case, we propose a system of simultaneously
constrained signed-CS problems to reconstruct a sparse signal from its Level
Crossings (LC)s and modify both the Binary Iterative Hard Thresholding (BIHT)
and BSL0 algorithms to solve this problem. Simulation results demonstrate
superior performance of the proposed LC reconstruction techniques in comparison
with the literature.


title: Chiral optical Local Density of States in spiral plasmonic cavity

abstract:
  We introduce a new paradigm: the chiral electromagnetic local density of
states (LDOS) in a spiral plasmonic nanostructure. In both classical and
quantum regimes, we reveal using scanning near-field optical microscopy (NSOM)
in combination with spin analysis that a spiral cavity possesses spin-dependent
local optical modes. We expect this work to lead to promising directions for
future quantum plasmonic device development, highlighting the potentials of
chirality in quantum information processing.


title:
Combined Bulk and Surface Radiation Damage Effects at Very High Fluences
  in Silicon Detectors: Measurements and TCAD Simulations

abstract:
  In this work we propose a new combined TCAD radiation damage modelling
scheme, featuring both bulk and surface radiation damage effects, for the
analysis of silicon detectors aimed at the High Luminosity LHC. In particular,
a surface damage model has been developed by introducing the relevant
parameters (NOX, NIT) extracted from experimental measurements carried out on
p-type substrate test structures after gamma irradiations at doses in the range
10-500 Mrad(Si). An extended bulk model, by considering impact ionization and
deep-level cross-sections variation, was included as well. The model has been
validated through the comparison of the simulation findings with experimental
measurements carried out at very high fluences (2 10^16 1 MeV equivalent
n/cm^2) thus fostering the application of this TCAD approach for the design and
optimization of the new generation of silicon detectors to be used in future
HEP experiments.


title:
Photon emissivity in the vicinity of a critical point - A case study
  within the quark meson model

abstract:
  The quark meson (linear sigma) model with linearized fluctuations displays at
a critical end point the onset of a curve of first-order phase transitions
(FOPTs) located at non-zero chemical potentials and temperatures below a
certain cross-over temperature. The model qualifies well for an illustrative
example to study the impact of the emerging FOPT, e.g. on photon emissivities.
Such a case study unravels the tight interlocking of the phase structure with
the emission rates, here calculated according to lowest-order tree level
processes by kinetic theory expressions. It is the strong dependence of the
rates on the effective masses of the involved degrees of freedom which
distinctively vary over the phase diagram thus shaping the emissivity
accordingly. At the same time, thermodynamic properties of the medium are
linked decisively to these effective masses, i.e. a consistent evaluation of
thermodynamics, governing for instance adiabatic expansion paths, and emission
rates is maintained within such an approach.


title: A note on the real part of complex chromatic roots

abstract:
  A {\em chromatic root} is a root of the chromatic polynomial of a graph.
While the real chromatic roots have been extensively studied and well
understood, little is known about the {\em real parts} of chromatic roots. It
is not difficult to see that the largest real chromatic root of a graph with
$n$ vertices is $n-1$, and indeed, it is known that the largest real chromatic
root of a graph is at most the tree-width of the graph. Analogous to these
facts, it was conjectured in [8] that the real parts of chromatic roots are
also bounded above by both $n-1$ and the tree-width of the graph.
  In this article we show that for all $k\geq 2$ there exist infinitely many
graphs $G$ with tree-width $k$ such that $G$ has non-real chromatic roots $z$
with $\Re(z)>k$. We also discuss the weaker conjecture and prove it for graphs
$G$ with $\chi(G)\geq n-3$.


title:
Prompt charmonia production and polarization at LHC in the NRQCD with
  $k_T$-factorization. Part III: $J/\psi$ meson

abstract:
  In the framework of $k_T$-factorization approach, the production and
polarization of prompt $J/\psi$ mesons at the LHC energies is studied. Our
consideration is based on the non-relativistic QCD formalism for bound states
and off-shell amplitudes for hard partonic subprocesses. Both the direct
production mechanism and feed-down contributions from $\chi_c$ and $\psi(2S)$
decays are taken into account. The transverse momentum dependent (or
unintegrated) gluon densities in a proton were derived from
Ciafaloni-Catani-Fiorani-Marchesini evolution equation or, alternatively, were
chosen in accordance with Kimber-Martin-Ryskin prescription. The
non-perturbative color-octet matrix elements were first deduced from the fits
to the latest CMS data on $J/\psi$ transverse momentum distributions and then
applied to describe the ATLAS and LHCb data on $J/\psi$ production and
polarization at $\sqrt s = 7$, $8$ and $13$ TeV. We perform an estimation of
polarization parameters $\lambda_\theta$, $\lambda_\phi$ and $\lambda_{\theta
\phi}$ which determine $J/\psi$ spin density matrix and demonstrate that
treating the soft gluon emission as a series of explicit color-electric dipole
transitions within NRQCD leads to unpolarized $J/\psi$ production at high
transverse momenta, that is in qualitative agreement with the LHC data.


title:
Fast and backward stable computation of the eigenvalues and eigenvectors
  of matrix polynomials

abstract:
  In the last decade matrix polynomials have been investigated with the primary
focus on adequate linearizations and good scaling techniques for computing
their eigenvalues and eigenvectors. In this article we propose a new method for
computing a factored Schur form of the associated companion pencil. The
algorithm has a quadratic cost in the degree of the polynomial and a cubic one
in the size of the coefficient matrices. Also the eigenvectors can be computed
at the same cost.
  The algorithm is a variant of Francis's implicitly shifted QR algorithm
applied on the companion pencil. A preprocessing unitary equivalence is
executed on the matrix polynomial to simultaneously bring the leading matrix
coefficient and the constant matrix term to triangular form before forming the
companion pencil. The resulting structure allows us to stably factor each
matrix of the pencil as a product of $k$ matrices of unitary-plus-rank-one
form, admitting cheap and numerically reliable storage. The problem is then
solved as a product core chasing eigenvalue problem. A backward error analysis
is included, implying normwise backward stability after a proper scaling.
Computing the eigenvectors via reordering the Schur form is discussed as well.
  Numerical experiments illustrate stability and efficiency of the proposed
methods.


title: Horadam Octonions

abstract:
  In this paper, first we define Horadam octonions by Horadam sequence which is
a generalization of second order recurrence relations. Also, we give some
fundamental properties involving the elements of that sequence. Then, we obtain
their Binet-like formula, ordinary generating function and Cassini identity.


title:
Higher-order baryon number susceptibilities: interplay between the
  chiral and the nuclear liquid-gas transitions

abstract:
  We use an improved version of the SU(3) flavour parity-doublet quark-hadron
model to investigate the higher order baryon number susceptibilities near the
chiral and the nuclear liquid-gas transitions. The parity-doublet model has
been improved by adding higher-order interaction terms of the scalar fields in
the effective mean field Lagrangian, resulting in a much-improved description
of nuclear ground-state properties, in particular the nuclear compressibility.
The resulting phase diagram of the model agrees qualitatively with expectations
from lattice QCD, i.e., it shows a crossover at zero net baryo-chemical
potential and a critical point at finite density. Using this model, we
investigate the dependence of the higher-order baryon number susceptibilities
as function of temperature and chemical potential. We observe a strong
interplay between the chiral and liquid-gas transition at intermediate baryo
chemical potentials. Due to this interplay between the chiral and the nuclear
liquid-gas transitions, the experimentally measured cumulants of the net baryon
number may show very different beam energy dependence, subject to the actual
freeze-out temperature.


title:
Unveiling the Charge Density Wave Inhomogeneity and Pseudogap State in
  1T-TiSe2

abstract:
  By using scanning tunneling microscopy (STM) / spectroscopy (STS), we
systematically characterize the electronic structure of lightly doped 1T-TiSe2,
and demonstrate the existence of the electronic inhomogeneity and the pseudogap
state. It is found that the intercalation induced lattice distortion impacts
the local band structure and reduce the size of the charge density wave (CDW)
gap with the persisted 2x2 spatial modulation. On the other hand, the
delocalized doping electrons promote the formation of pseudogap. Domination by
either of the two effects results in the separation of two characteristic
regions in real space, exhibiting rather different electronic structures.
Further doping electrons to the surface confirms that the pseudogap may be the
precursor for the superconducting gap. This study suggests that the competition
of local lattice distortion and the delocalized doping effect contribute to the
complicated relationship between charge density wave and superconductivity for
intercalated 1T-TiSe2.


title: Matching Multiplications in Bit-Vector Formulas

abstract:
  Bit-vector formulas arising from hardware verification problems often contain
word-level arithmetic operations. Empirical evidence shows that
state-of-the-art SMT solvers are not very efficient at reasoning about
bit-vector formulas with multiplication. This is particularly true when
multiplication operators are decomposed and represented in alternative ways in
the formula.We present a pre-processing heuristic that identifies certain types
of decomposed multipliers, and adds special assertions to the input formula
encoding the equivalence of sub-terms to word-level multiplication. The
pre-processed formulas are then solved using an SMT solver. Our experiments
with three SMT solvers show that our heuristic allows several formulas to be
solved quickly, while the same formulas time out without the pre-processing
step.


title: Eulerian polynomials and polynomial congruences

abstract:
  We prove that the Eulerian polynomial satisfies certain polynomial
congruences. Furthermore, these congruences characterize the Eulerian
polynomial.


title:
Group interpretation of the spectral parameter. The case of isothermic
  surfaces

abstract:
  It is well known that in some cases the spectral parameter has a group
interpretation. We discuss in detail the case of Gauss-Codazzi equations for
isothermic surfaces immersed in $E^3$. The algebra of Lie point symmetries is
4-dimensional and all these symmetries are also symmetries of the
Gaus-Weingarten equations (which can be considered as so(3)-valued
non-parametric linear problem). In order to obtain a non-removable spectral
parameter one has to consider so(4,1)-valued linear problem which has a
3-dimensional algebra of Lie point symmetries. The missing symmetry introduces
a non-removable parameter. In the second part of the paper we extend these
results on the case of isothermic immersions in arbitrary multidimensional
Euclidean spaces. In order to simplify calculations the problem was formulated
in terms of a Clifford algebra.


title: $\mathcal{Q}^{+}$: Characterising the structure of young star clusters

abstract:
  Many young star clusters appear to be fractal, i.e. they appear to be
concentrated in a nested hierarchy of clusters within clusters. We present a
new algorithm for statistically analysing the distribution of stars to quantify
the level of sub-structure. We suggest that, even at the simplest level, the
internal structure of a fractal cluster requires the specification of three
parameters. (i) The 3D fractal dimension, $\mathcal{D}$, measures the extent to
which the clusters on one level of the nested hierarchy fill the volume of
their parent cluster. (ii) The number of levels, $\mathcal{L}$, reflects the
finite ratio between the linear size of the large root-cluster at the top of
the hierarchy, and the smallest leaf-clusters at the bottom of the hierarchy.
(iii) The volume-density scaling exponent, $\mathcal{C}=-\textrm{d}\ln[\delta
n]/\textrm{d}\ln[L]$ measures the factor by which the excess density, $\delta
n$, in a structure of scale $L$, exceeds that of the background formed by
larger structures; it is similar, but not exactly equivalent, to the exponent
in Larson's scaling relation between density and size for molecular clouds. We
describe an algorithm which can be used to constrain the values of $({\cal
D},{\cal L},{\cal C})$ and apply this method to artificial and observed
clusters. We show that this algorithm is able to reliably describe the three
dimensional structure of an artificial star cluster from the two dimensional
projection, and quantify the varied structures observed in real and simulated
clusters.


title:
Event patterns extracted from top quark-related spectra in proton-proton
  collisions at 8 TeV

abstract:
  We analyze the transverse momentum ($p_T$) and rapidity ($y$) spectra of top
quark pairs, hadronic top quarks, and top quarks produced in proton-proton
($pp$) collisions at center-of-mass energy $\sqrt{s}=8$ TeV. For $p_T$ spectra,
we use the superposition of the inverse power-law suggested by the QCD (quantum
chromodynamics) calculus and the Erlang distribution resulting from a
multisource thermal model. For $y$ spectra, we use the two-component Gaussian
function resulting from the revised Landau hydrodynamic model. The modelling
results are in agreement with the experimental data measured at the detector
level, in the fiducial phase-space, and in the full phase-space by the ATLAS
Collaboration at the Large Hadron Collider (LHC). Based on the parameter values
extracted from $p_T$ and $y$ spectra, the event patterns in three-dimensional
velocity ($\beta_x$-$\beta_y$-$\beta_z$), momentum ($p_x$-$p_y$-$p_z$), and
rapidity ($y_1$-$y_2$-$y$) spaces are obtained, and the probability
distributions of these components are also obtained.


title: Entropy spectrum of charged BTZ black holes in massive gravity's rainbow

abstract:
  Regarding the significant interests in massive gravity and combining it with
gravity's rainbow and also BTZ black holes, we apply the formalism introduced
by Jiang and Han in order to investigate the quantization of the entropy of
black holes. We show that the entropy of BTZ black holes in massive gravity's
rainbow is quantized with equally spaced spectra and it depends on the black
holes' properties including massive parameters, electrical charge, the
cosmological constant and also rainbow functions. In addition, we show that
quantization of the entropy results into the appearance of novel properties for
this quantity such as; the existence of divergencies, non-zero entropy in
vanishing horizon radius and possibility of tracing out the effects of black
holes' properties. Such properties are absent in the non-quantized version of
these black holes' entropy. Furthermore, we investigate the effects of
quantization on the thermodynamical behavior of the solutions. We confirm that
due to quantization, novel phase transitions points are introduced and stable
solutions are limited to only dS black holes (AdS and asymptotically flat
solutions are unstable).


title:
Combining Data-driven and Model-driven Methods for Robust Facial
  Landmark Detection

abstract:
  Facial landmark detection is an important yet challenging task for real-world
computer vision applications. This paper proposes an effective and robust
approach for facial landmark detection by combining data- and model-driven
methods. Firstly, a Fully Convolutional Network (FCN) is trained to compute
response maps of all facial landmark points. Such a data-driven method could
make full use of holistic information in a facial image for global estimation
of facial landmarks. After that, the maximum points in the response maps are
fitted with a pre-trained Point Distribution Model (PDM) to generate the
initial facial shape. This model-driven method is able to correct the
inaccurate locations of outliers by considering the shape prior information.
Finally, a weighted version of Regularized Landmark Mean-Shift (RLMS) is
employed to fine-tune the facial shape iteratively. This
Estimation-Correction-Tuning process perfectly combines the advantages of the
global robustness of data-driven method (FCN), outlier correction capability of
model-driven method (PDM) and non-parametric optimization of RLMS. Results of
extensive experiments demonstrate that our approach achieves state-of-the-art
performances on challenging datasets including 300W, AFLW, AFW and COFW. The
proposed method is able to produce satisfying detection results on face images
with exaggerated expressions, large head poses, and partial occlusions.


title: Tautological rings on Jacobian varieties of curves with automorphisms

abstract:
  Let $J$ be the Jacobian of a smooth projective complex curve $C$ which admits
non-trivial automorphisms, and let $A(J)$ be the ring of algebraic cycles on
$J$ with rational coefficients modulo algebraic equivalence. We present new
tautological rings in $A(J)$ which extend in a natural way the tautological
ring studied by Beauville (Compos Math 140(3):683-688, 2004). We then show
there exist tautological rings induced on special complementary abelian
subvarieties of $J$.


title: A Majoritarian Representative Voting System

abstract:
  We present an alternative voting system that aims at bridging the gap between
proportional representative systems and majoritarian, single winner election
systems. The system lets people vote for multiple parties, but then assigns
each ballot to a single party. This opens a whole range of possible systems,
all representative. We show theoretically that this space is convex. Then among
the possible parliaments we present an algorithm to produce the most
majoritarian result. We then test the system and compare the results with a
pure proportional and a majoritarian voting system showing how the results are
comparable with the majoritarian system. Then we simulate the system and show
how it tends to produce parties of exponentially decreasing size with always a
first, major party. Finally we describe how the system can be used in a context
of a parliament made up of two separate houses.


title: Top and Electroweak bosons and Higgs

abstract:
  I review recent progress in the computation of processes involving top quarks
in the framework of Standard Model Effective Theory at NLO in QCD. In
particular I discuss the impact of higher-dimensional operators on top pair
production in association with a photon, a Z boson and a Higgs. Results are
obtained within the automated framework of MadGraph5_aMC@NLO.


title: Payoff-Based Approach to Learning Nash Equilibria in Convex Games

abstract:
  We consider multi-agent decision making, where each agent optimizes its cost
function subject to constraints. Agents' actions belong to a compact convex
Euclidean space and the agents' cost functions are coupled. We propose a
distributed payoff-based algorithm to learn Nash equilibria in the game between
agents. Each agent uses only information about its current cost value to
compute its next action. We prove convergence of the proposed algorithm to a
Nash equilibrium in the game leveraging established results on stochastic
processes. The performance of the algorithm is analyzed with a numerical case
study.


title:
$L^p$ solution of backward stochastic differential equations driven by a
  marked point process

abstract:
  We obtain existence and uniqueness in L^p, p>1 of the solutions of a backward
stochastic differential equations (BSDEs for short) driven by a marked point
process, on a bounded interval. We show that the solution of the BSDE can be
approximated by a finite system of deterministic differential equations. As
application we address an optimal control problems for point processes of
general non-Markovian type and show that BSDEs can be used to prove existence
of an optimal control and to represent the value function.


title:
Positivity of the top Lyapunov exponent for cocycles on semisimple Lie
  groups over hyperbolic bases

abstract:
  A theorem of Viana says that almost all cocycles over any hyperbolic system
have nonvanishing Lyapunov exponents. In this note we extend this result to
cocycles on any noncompact classical semisimple Lie group.


title: Bridges in Complex Networks

abstract:
  A bridge in a graph is an edge whose removal disconnects the graph and
increases the number of connected components. We calculate the fraction of
bridges in a wide range of real-world networks and their randomized
counterparts. We find that real networks typically have more bridges than their
completely randomized counterparts, but very similar fraction of bridges as
their degree-preserving randomizations. We define a new edge centrality
measure, called bridgeness, to quantify the importance of a bridge in damaging
a network. We find that certain real networks have very large average and
variance of bridgeness compared to their degree-preserving randomizations and
other real networks. Finally, we offer an analytical framework to calculate the
bridge fraction , the average and variance of bridgeness for uncorrelated
random networks with arbitrary degree distributions.


title:
When Students Choose to Use Event-B in their Software Engineering
  Projects

abstract:
  Students often learn formal methods as part of a software engineering degree
programme, without applying these formal methods outside of the specific
module(s) dedicated to this subject. In particular, software engineering
students often have to build a significant application/program/system in a
substantial project at the end of their programme (in order to demonstrate the
application of the things they have learned during the previous taught
modules). Our experience shows that the majority of students do not use formal
methods in this project work. We report on feedback from the minority of
students who did choose to use formal methods in their projects, and give
examples of where this was a help and where it was a hindrance.


title: Sovereignty of the Apps: There's more to Relevance than Downloads

abstract:
  The value of mobile apps is traditionally measured by metrics such as the
number of downloads, installations, or user ratings. A problem with these
measures is that they reflect actual usage at most indirectly. Indeed, analytic
companies have suggested that retention rates, i.e., the number of days users
continue to interact with an installed app are low. We conduct the first
independent and large-scale study of retention rates and usage behavior trends
in the wild. We study their impact on a large-scale database of app-usage data
from a community of 339,842 users and more than 213,667 apps. Our analysis
shows that, on average, applications lose 70% of their users in the first week,
while very popular applications (top 100) lose only 45%. It also reveals,
however, that many applications have more complex usage behavior patterns due
to seasonality, marketing, or other factors. To capture such effects, we
develop a novel app-usage behavior trend measure which provides instantaneous
information about the "hotness" of an application. We identify typical trends
in app popularity and classify applications into archetypes. From these, we can
distinguish, for instance, trendsetters from copycat apps. In our results,
roughly 40% of all apps never gain more than a handful of users. Less than 0.4%
of the remaining 60% are constantly popular, 1% flop after an initial steep
rise, and 7% continuously rise in popularity. We conclude by demonstrating that
usage behavior trend information can be used to develop better mobile app
recommendations. With the proposed usage-based measures (retention and trend),
we are able to shift sovereignty in app recommendations back to where it really
matters: actual usage statistics, in contrast to download count and user
ratings which are prone to manipulation by people.


title:
Predicting the Category and Attributes of Visual Search Targets Using
  Deep Gaze Pooling

abstract:
  Predicting the target of visual search from eye fixation (gaze) data is a
challenging problem with many applications in human-computer interaction. In
contrast to previous work that has focused on individual instances as a search
target, we propose the first approach to predict categories and attributes of
search targets based on gaze data. However, state of the art models for
categorical recognition, in general, require large amounts of training data,
which is prohibitive for gaze data. To address this challenge, we propose a
novel Gaze Pooling Layer that integrates gaze information into CNN-based
architectures as an attention mechanism - incorporating both spatial and
temporal aspects of human gaze behavior. We show that our approach is effective
even when the gaze pooling layer is added to an already trained CNN, thus
eliminating the need for expensive joint data collection of visual and gaze
data. We propose an experimental setup and data set and demonstrate the
effectiveness of our method for search target prediction based on gaze
behavior. We further study how to integrate temporal and spatial gaze
information most effectively, and indicate directions for future research in
the gaze-based prediction of mental states.


title: Using Microfluidic Device to Study Rheological Properties of Heavy Oil

abstract:
  In this study, capillary-driven flow of different pure liquids and diluted
bitumen samples were studied using microfluidic channel (width of 30 um and
depth of 9 um). Capillary filling kinetics of liquids as a function of time
were evaluated and compared with theoretical predictions. For pure liquids
including water, toluene, hexane, and methanol experimental results agreed well
with theoretical predictions. However, for bitumen samples, as concentration of
bitumen increased the deviation between theoretical and experimental results
became larger. The higher deviation for high concentrations (i.e. above 30%)
can be due to the difference between dynamic contact angle and bulk contact
angle. Microchannels are suitable experimental devices to study the flow of
heavy oil and bitumen in porous structure such as those of reservoirs.


title:
On infinite dimensional linear programming approach to stochastic
  control

abstract:
  We consider the infinite dimensional linear programming (inf-LP) approach for
solving stochastic control problems. The inf-LP corresponding to problems with
uncountable state and input spaces is in general computationally intractable.
By focusing on linear systems with quadratic cost (LQG), we establish a
connection between this approach and the well-known Riccati LMIs. In
particular, we show that the semidefinite programs known for the LQG problem
can be derived from the pair of primal and dual inf-LPs. Furthermore, we
establish a connection between multi-objective and chance constraint criteria
and the inf-LP formulation.


title:
Exponential convergence of the hp Virtual Element Method with corner
  singularities

abstract:
  In the present work, we analyze the $hp$ version of Virtual Element methods
for the 2D Poisson problem. We prove exponential convergence of the energy
error employing sequences of polygonal meshes geometrically refined, thus
extending the classical choices for the decomposition in the $hp$ Finite
Element framework to very general decomposition of the domain. A new
stabilization for the discrete bilinear form with explicit bounds in $h$ and
$p$ is introduced. Numerical experiments validate the theoretical results. We
also exhibit a numerical comparison between $hp$ Virtual Elements and $hp$
Finite Elements.


title:
Proximity Effect Transfer from NbTi into a Semiconductor Heterostructure
  via Epitaxial Aluminum

abstract:
  We demonstrate the transfer of the superconducting properties of NbTi---a
large-gap high-critical-field superconductor---into an InAs heterostructure via
a thin intermediate layer of epitaxial Al. Two device geometries, a Josephson
junction and a gate-defined quantum point contact, are used to characterize
interface transparency and the two-step proximity effect. In the Josephson
junction, multiple Andreev reflection reveal near-unity transparency, with an
induced gap $\Delta^*=0.50~\mathrm{meV}$ and a critical temperature of
$7.8~\mathrm{K}$. Tunneling spectroscopy yields a hard induced gap in the InAs
adjacent to the superconductor of $\Delta^*=0.43~\mathrm{meV}$ with
substructure characteristic of both Al and NbTi.


title: Thresholds for contagious sets in random graphs

abstract:
  For fixed $r\geq 2$, we consider bootstrap percolation with threshold $r$ on
the Erd\H{o}s-R\'enyi graph ${\cal G}_{n,p}$. We identify a threshold for $p$
above which there is with high probability a set of size $r$ which can infect
the entire graph. This improves a result of Feige, Krivelevich and Reichman,
which gives bounds for this threshold, up to multiplicative constants.
  As an application of our results, we also obtain an upper bound for the
threshold for $K_4$-bootstrap percolation on ${\cal G}_{n,p}$, as studied by
Balogh, Bollob\'as and Morris. We conjecture that our bound is asymptotically
sharp.
  These thresholds are closely related to the survival probabilities of certain
time-varying branching processes, and we derive asymptotic formulae for these
survival probabilities which are of interest in their own right.


title:
On the extension of Fredholm determinants to the mixed multidimensional
  integral operators with regulated kernels

abstract:
  We extend the classical trace (and determinant) known for the integral
operators $$ ({\mathcal I}+)\int_{[0,1)^N}{\bf A}({\bf k},{\bf x}){\bf u}({\bf
x})d{\bf x} $$ with matrix-valued kernels ${\bf A}$ to the operators of the
form $$ \sum_{\alpha}\int_{[0,1)^{|\alpha|}}{\bf A}({\bf k},{\bf
x}_{\alpha}){\bf u}({\bf k}_{\overline{\alpha}},{\bf x}_{\alpha})d{\bf
x}_{\alpha}, $$ where $\alpha$ are arbitrary subsets of the set $\{1,...,N\}$.
Such operators form a Banach algebra containing simultaneously all integral
operators of the dimensions $\leqslant N$. In this sense, it is a largest
algebra where explicit traces and determinants are constructed. Such operators
arise naturally in the mechanics and physics of waves propagating through
periodic structures with various defects. We give an explicit representation of
the inverse operators (resolvent) and describe the spectrum by using zeroes of
the determinants. Due to the structure of the operators, we have $2^N$
different determinants, each of them describes the spectral component of the
corresponding dimension.


title:
Links between the personalities, styles and performance in computer
  programming

abstract:
  There are repetitive patterns in strategies of manipulating source code. For
example, modifying source code before acquiring knowledge of how a code works
is a depth-first style and reading and understanding before modifying source
code is a breadth-first style. To the extent we know there is no study on the
influence of personality on them. The objective of this study is to understand
the influence of personality on programming styles. We did a correlational
study with 65 programmers at the University of Stuttgart. Academic achievement,
programming experience, attitude towards programming and five personality
factors were measured via self-assessed survey. The programming styles were
asked in the survey or mined from the software repositories. Performance in
programming was composed of bug-proneness of programmers which was mined from
software repositories, the grades they got in a software project course and
their estimate of their own programming ability. We did statistical analysis
and found that Openness to Experience has a positive association with
breadth-first style and Conscientiousness has a positive association with
depth-first style. We also found that in addition to having more programming
experience and better academic achievement, the styles of working depth-first
and saving coarse-grained revisions improve performance in programming.


title: On the condition for correct convergence in the complex Langevin method

abstract:
  The complex Langevin method (CLM) provides a promising way to perform the
path integral with a complex action using a stochastic equation for
complexified dynamical variables. It is known, however, that the method gives
wrong results in some cases, while it works, for instance, in finite density
QCD in the deconfinement phase or in the heavy dense limit. Here we revisit the
argument for justification of the CLM and point out a subtlety in using the
time-evolved observables, which play a crucial role in the argument. This
subtlety requires that the probability distribution of the drift term should
fall off exponentially or faster at large magnitude. We demonstrate our claim
in some examples such as chiral Random Matrix Theory and show that our
criterion is indeed useful in judging whether the results obtained by the CLM
are trustable or not.


title:
Stability selection for component-wise gradient boosting in multiple
  dimensions

abstract:
  We present a new algorithm for boosting generalized additive models for
location, scale and shape (GAMLSS) that allows to incorporate stability
selection, an increasingly popular way to obtain stable sets of covariates
while controlling the per-family error rate (PFER). The model is fitted
repeatedly to subsampled data and variables with high selection frequencies are
extracted. To apply stability selection to boosted GAMLSS, we develop a new
"noncyclical" fitting algorithm that incorporates an additional selection step
of the best-fitting distribution parameter in each iteration. This new
algorithms has the additional advantage that optimizing the tuning parameters
of boosting is reduced from a multi-dimensional to a one-dimensional problem
with vastly decreased complexity. The performance of the novel algorithm is
evaluated in an extensive simulation study. We apply this new algorithm to a
study to estimate abundance of common eider in Massachusetts, USA, featuring
excess zeros, overdispersion, non-linearity and spatio-temporal structures.
Eider abundance is estimated via boosted GAMLSS, allowing both mean and
overdispersion to be regressed on covariates. Stability selection is used to
obtain a sparse set of stable predictors.


title: Localization of Vector Field on Dynamical Domain Wall

abstract:
  In the previous works (arXiv:1202.5375 and 1402.1346), the dynamical domain
wall, where the four dimensional FRW universe is embedded in the five
imensional space-time, has been realized by using two scalar fields. In this
paper, we consider the localization of vector field in three formulations. The
first formulation was investigated in the previous paper (arXiv:1510.01099) for
the $U(1)$ gauge field. In the second formulation, we investigate the
Dvali-Shifman mechanism (hep-th/9612128), where the non-abelian gauge field is
confined in the bulk but the gauge symmetry is spontaneously broken on the
domain wall. In the third formulation, we investigate the Kaluza-Klein modes
coming from the five dimensional graviton. In the Randall-Sundrum model, the
graviton was localized on the brane. We show that the $(5,\mu)$ components
$\left(\mu=0,1,2,3\right)$ of the graviton are also localized on the domain
wall and can be regarded as the vector field on the domain wall. There are,
however, some corrections coming from the bulk extra dimension if the domain
wall universe is expanding.


title:
Yellow Light Energy Transfer Emitting Diodes Based on mixed Quasi-2D
  Perovskites

abstract:
  The new class of hybrid organic-inorganic semiconductor (HOIS) materials,
based on halide perovskites, is constantly being pursued for applications such
as Light Emitting Diodes (LEDs) and solar cells, due to their momentous
optoelectronic properties. In this work, we present a single layer LED that
operates due to energy transfer effects as well as a simple, instant and low
cost method for its fabrication. A LED device based on a mixture of zero
dimensional (OD) (CH 3 NH 3 ) 4 PbI 6, two dimensional (2D) (F- C 6 H 4 CH 2 CH
2 NH 2 ) 2 PbI 4 and three dimensional (3D) (CH 3 NH 3 )PbI 3 HOIS, is
presented for the first time. The final composite material manifests simple,
yet unique energy transfer optical effects, while its electroluminescence
exhibits excitonic recombination bright yellow light, peaked at 592 nm. LED
device fabricated under ambient air, readily functions at room temperature and
low voltages. As for the active layer, it exhibited substantial film continuity
in any form of deposition. Finally, with appropriate mixtures, it is possible
to create films containing phase changes that exhibit dual color emission, here
presented as yellow-green.

categories: physics.optics cond-mat.mes-hall cond-mat.mtrl-sci physics.chem-ph


title: A low-cost, arduino-like dev-kit for single-element ultrasound imaging

abstract:
  Ultrasound imaging is developing an open-source ecosystem, especially for
software frameworks. Little exists on the open-hardware side. Hence a focus was
put on producing easy-to-use technological (hardware and software) kit to allow
anyone - scientists, academics, hackers, makers to have a experimental setup
for ultrasound imaging at a low cost, at home, with no specific equipment
required.
  To this end, open source, arduino-like modules have been developed to build a
simple, but complete, single channel analog front-end system, where all
intermediary signals are readily accessible by the user. A single-channel
architecture allows to avoid the beam-forming head, though it limits the
quality of the image obtained, and brings robustness to the system. Moreover,
complex RF processing, being shifted to the analog side, limits the quality of
the final image.
  These were tested with re-purposed ultrasound mechanical scanner heads, as
well as re-purposed medical imaging transducers, and provided interesting
images. Moreover, such modules could also be used in RF projects,
non-destructive projects, low-cost medical imaging projects.


title: Power Counting in Peripheral Partial Waves: The Singlet Channels

abstract:
  We analyze the power counting of the peripheral singlet partial waves in
nucleon-nucleon scattering. In agreement with conventional wisdom, we find that
pion exchanges are perturbative in the peripheral singlets. We quantify from
the effective field theory perspective the well-known suppression induced by
the centrifugal barrier in the pion-exchange interactions. By exploring
perturbation theory up to fourth order, we find that the one-pion-exchange
potential in these channels is demoted from leading to subleading order by a
given power of the expansion parameter that grows with the orbital angular
momentum. We discuss the implications of these demotions for few-body
calculations: though higher partial waves have been known for a long time to be
irrelevant in these calculations (and are hence ignored), here we explain how
to systematize the procedure in a way that is compatible with the effective
field theory expansion.


title: Effective Quantization Methods for Recurrent Neural Networks

abstract:
  Reducing bit-widths of weights, activations, and gradients of a Neural
Network can shrink its storage size and memory usage, and also allow for faster
training and inference by exploiting bitwise operations. However, previous
attempts for quantization of RNNs show considerable performance degradation
when using low bit-width weights and activations. In this paper, we propose
methods to quantize the structure of gates and interlinks in LSTM and GRU
cells. In addition, we propose balanced quantization methods for weights to
further reduce performance degradation. Experiments on PTB and IMDB datasets
confirm effectiveness of our methods as performances of our models match or
surpass the previous state-of-the-art of quantized RNN.


title: Quasifission dynamics and stability of superheavy systems

abstract:
  Recent experiments revealed intriguing similarities in the
$^{64}$Ni+$^{207}$Pb, $^{132}$Xe+$^{208}$Pb, and $^{238}$U+$^{238}$U reactions
at energies around the Coulomb barrier. The experimental data indicate that for
all systems substantial energy dissipation takes place, in the first stage of
the reaction, although the number of transferred nucleons is small. On the
other hand, in the second stage, a large number of nucleons are transferred
with small friction and small consumption of time. To understand the observed
behavior, various reactions were analyzed based on the microscopic
time-dependent Hartree-Fock (TDHF) theory. From a systematic analysis for
$^{40,48}$Ca+$^{124}$Sn, $^{40}$Ca+$^{208}$Pb, $^{40}$Ar+$^{208}$Pb,
$^{58}$Ni+$^{208}$Pb, $^{64}$Ni+$^{238}$U, $^{136}$Xe+ $^{198}$Pt, and
$^{238}$U+$^{238}$U reactions, we find that TDHF reproduces well the measured
trends. In addition, the Balian-V\'en\'eroni variational principle is applied
to head-on collisions of $^{238}$U+$^{238}$U, and the variance of the fragment
masses is compared with the experimental data, showing significant improvement.
The underlying reaction mechanisms and possible future studies are discussed.


title: An analytical test case for dust dynamics during a shock-wave passage

abstract:
  An exact solution of a forced Burgers' equation representing the dynamics of
a "dust fluid" in a one-dimensional flow is presented. The test case considered
starts with a steady (time independent) two-fluid flow in one dimension, where
the two fluid components represent gas and dust. It is then assumed that a
shock wave travels through the gas at a constant speed and without radiative
energy losses and diffusion. Then, adopting a constant stopping time for the
dust particles in the dust fluid (mono-dispersed grain sizes), the equation of
motion for the dust fluid can be transformed into a simple ordinary
differential equation, which is satisfied by the Wright omega function.
Implications for the formation of detached shells around carbon stars are
briefly discussed.


title: Energy shift of H-atom electrons due to Gibbons-Hawking thermal bath

abstract:
  The electromagnetic shift of energy levels of H-atom electrons is determined
by calculating an electron coupling to the Gibbons-Hawking electromagnetic
field thermal bath. Energy shift of electrons in H-atom is determined in the
framework of the non-relativistic quantum mechanics.


title:
Convergence to harmonic maps for the Landau-Lifshitz flows on two
  dimensional hyperbolic spaces

abstract:
  In this paper, we prove that the solution of the Landau-Lifshitz flow
$u(t,x)$ from $\mathbb{H}^2$ to $\mathbb{H}^2$ converges to some harmonic map
as $t\to\infty$. The essential observation is that although there exist
infinite numbers of harmonic maps from $\Bbb H^2$ to $\Bbb H^2$, the heat flow
initiated from $u(t,x)$ for any given $t>0$ converges to the same harmonic map
as the heat flow initiated from $u(0,x)$. This observation enables us to
construct a variant of Tao's caloric gauge to reduce the convergence to
harmonic maps for the Landau-Lifshitz flow to the decay of the corresponding
heat tension field. The advantage of the strategy used in this paper is that we
can see the limit harmonic map directly by evolving $u(0,x)$ along a heat flow
without evolving the Landau-Lifshitz flow to the infinite time.


title:
A Bayesian Network Approach to Assess and Predict Software Quality Using
  Activity-Based Quality Models

abstract:
  Context: Software quality is a complex concept. Therefore, assessing and
predicting it is still challenging in practice as well as in research.
Activity-based quality models break down this complex concept into concrete
definitions, more precisely facts about the system, process, and environment as
well as their impact on activities performed on and with the system. However,
these models lack an operationalisation that would allow them to be used in
assessment and prediction of quality. Bayesian networks have been shown to be a
viable means for this task incorporating variables with uncertainty. Objective:
The qualitative knowledge contained in activity-based quality models are an
abundant basis for building Bayesian networks for quality assessment. This
paper describes a four-step approach for deriving systematically a Bayesian
network from an assessment goal and a quality model. Method: The four steps of
the approach are explained in detail and with running examples. Furthermore, an
initial evaluation is performed, in which data from NASA projects and an open
source system is obtained. The approach is applied to this data and its
applicability is analysed. Results: The approach is applicable to the data from
the NASA projects and the open source system. However, the predictive results
vary depending on the availability and quality of the data, especially the
underlying general distributions. Conclusion: The approach is viable in a
realistic context but needs further investigation in case studies in order to
analyse its predictive validity.


title:
Deriving a Generalized, Actuator Position-Independent Expression for the
  Force Output of a Scissor Lift

abstract:
  Scissor lifts, a staple of mechanical design, especially in competitive
robotics, are a type of linkage that can be used to raise a load to some
height, when acted upon by some force, usually exerted by an actuator. The
position of this actuator, however, can affect the mechanical advantage and
velocity ratio of the system. Hence, there needs to be a concrete way to
analytically compare different actuator positions. However, all current
research into the analysis of scissor lifts either focusses only on the screw
jack configuration, or derives separate force expressions for different
actuator positions. This, once again, leaves the decision between different
actuator positions to trial and error, since the expression to test the potency
of the position can only be derived once the position is chosen. This paper
proposes a derivation for a general force expression, in terms of a few
carefully chosen position variables, which can be used to generate the force
expression for any actuator position. Hence, this expression illustrates
exactly how each of the position variables (called a, b and i in this paper, as
defined later) affect the force output, and hence can be used to pick an
appropriate actuator position, by choosing values for the position variables
that give the desired result.


title:
Features of collisionless turbulence in the intracluster medium from
  simulated Faraday rotation maps II: the effects of instabilities feedback

abstract:
  Statistical analysis of Faraday Rotation Measure (RM) maps of the
intracluster medium (ICM) of galaxy clusters provides a unique tool to evaluate
some spatial features of the magnetic fields there. Its combination with
numerical simulations of magnetohydrodynamic (MHD) turbulence allows the
diagnosis of the ICM turbulence. Being the ICM plasma weakly collisional, the
thermal velocity distribution of the particles naturally develops anisotropies
as a consequence of the large scale motions and the conservation of the
magnetic moment of the charged particles. A previous study (Paper I) analyzed
the impact of large scale thermal anisotropy on the statistics of RM maps
synthesized from simulations of turbulence; these simulations employed a
collisionless MHD model which considered a tensor pressure with uniform
anisotropy. In the present work, we extend that analysis to a collisionless MHD
model in which the thermal anisotropy develops according to the conservation of
the magnetic moment of the thermal particles. We also consider the effect of
anisotropy relaxation caused by the micro-scale mirror and firehose
instabilities. We show that if the relaxation rate is fast enough to keep the
anisotropy limited by the threshold values of the instabilities, the dispersion
and power spectrum of the RM maps are indistinguishable from those obtained
from collisional MHD. Otherwise, there is a reduction in the dispersion and
steepening of the power spectrum of the RM maps (compared to the collisional
case). Considering the first scenario, the use of collisional MHD simulations
for modeling the RM statistics in the ICM becomes better justified.


title: Can phoretic particles swim in two dimensions?

abstract:
  Artificial phoretic particles swim using self-generated gradients in chemical
species (self-diffusiophoresis) or charges and currents (self-electrophoresis).
These particles can be used to study the physics of collective motion in active
matter and might have promising applications in bioengineering. In the case of
self-diffusiophoresis, the classical physical model relies on a steady solution
of the diffusion equation, from which chemical gradients, phoretic flows and
ultimately the swimming velocity, may be derived. Motivated by disk-shaped
particles in thin films and under confinement, we examine the extension to two
dimensions. Because the two-dimensional diffusion equation lacks a steady state
with the correct boundary conditions, Laplace transforms must be used to study
the long-time behavior of the problem and determine the swimming velocity. For
fixed chemical fluxes on the particle surface, we find that the swimming
velocity ultimately always decays logarithmically in time. In the case of
finite Peclet numbers, we solve the full advection-diffusion equation
numerically and show that this decay can be avoided by the particle moving to
regions of unconsumed reactant. Finite advection thus regularizes the
two-dimensional phoretic problem.


title:
The infinite occupation number basis of bosons - solving a numerical
  challenge

abstract:
  In any bosonic lattice system, which is not dominated by local interactions
and thus "frozen" in a Mott-type state, numerical methods have to cope with the
infinite size of the corresponding Hilbert space even for finite lattice sizes.
While it is common practice to restrict the local occupation number basis to
$N_c$ lowest occupied states, the presence of a finite condensate fraction
requires the complete number basis for an exact representation of the many-body
ground state. In this work we present a novel truncation scheme to account for
contributions from higher number states. By simply adding a single
\textit{coherent-tail} state to this common truncation, we demonstrate
increased numerical accuracy and the possible increase in numerical efficiency
of this method for the Gutzwiller variational wave function and within
dynamical mean-field theory.


title:
The explicit asymptotic formula of divisor function on average over
  values of quadratic polynomial

abstract:
  Let $F({\bf x})={\bf x}^tQ_{\bf x}+\mathbf{b}^t{\bf x}+c\in\mathbb{Z}[{\bf
x}]$ be a quadratic polynomial in $\ell (\ge 3 )$ variables ${\bf x}
=(x_{1},...,x_{\ell})$, where $F({\bf x})$ is positive when ${\bf
x}\in\mathbb{R}_{\ge 1}^{\ell}$, $Q\in {\rm M}_{\ell}(\mathbb{Z})$ is an
$\ell\times\ell$ matrix and its discriminant $\det\left(Q^t+Q\right)\neq 0$. It
gives an explicit asymptotic formula for the following sum \[\sum_{{\bf x}\in
[1,X]^{\ell}\cap\mathbb{Z}^{\ell}}\tau\left(F({\bf x})\right), \] where $\tau$
is the divisor function.


title:
A Bayesian Network Approach to Assess and Predict Software Quality Using
  Activity-Based Quality Models (Conference Version)

abstract:
  Assessing and predicting the complex concept of software quality is still
challenging in practice as well as research. Activity-based quality models
break down this complex con- cept into more concrete definitions, more
precisely facts about the system, process and environment and their impact on
ac- tivities performed on and with the system. However, these models lack an
operationalisation that allows to use them in assessment and prediction of
quality. Bayesian Networks (BN) have been shown to be a viable means for
assessment and prediction incorporating variables with uncertainty. This paper
describes how activity-based quality models can be used to derive BN models for
quality assessment and pre- diction. The proposed approach is demonstrated in a
proof of concept using publicly available data.


title: A $p$-adic supercongruence for truncated hypergeometric series ${}_7F_6$

abstract:
  Using an identity due to Gessel and Stanton and some properties of the
$p$-adic Gamma function, we establish a $p$-adic supercongruence for truncated
hypergeometric series ${}_7F_6$. From it we deduce some related
supercongruences, which extend certain recent results and confirm a
supercongruence conjecture.


title: Bayesian data analysis tools for atomic physics

abstract:
  We present an introduction to some concepts of Bayesian data analysis in the
context of atomic physics. Starting from basic rules of probability, we present
the Bayes' theorem and its applications. In particular we discuss about how to
calculate simple and joint probability distributions and the Bayesian evidence,
a model dependent quantity that allows to assign probabilities to different
hypotheses from the analysis of a same data set. To give some practical
examples, these methods are applied to two concrete cases. In the first
example, the presence or not of a satellite line in an atomic spectrum is
investigated. In the second example, we determine the most probable model among
a set of possible profiles from the analysis of a statistically poor spectrum.
We show also how to calculate the probability distribution of the main spectral
component without having to determine uniquely the spectrum modeling. For these
two studies, we implement the program Nested fit to calculate the different
probability distributions and other related quantities. Nested fit is a
Fortran90/Python code developed during the last years for analysis of atomic
spectra. As indicated by the name, it is based on the nested algorithm, which
is presented in details together with the program itself.


title: Magnetic anisotropy in surface-supported single-ion lanthanide complexes

abstract:
  Single-ion lanthanide-organic complexes can provide stable magnetic moments
with well-defined orientation for spintronic applications on the atomic level.
Here, we show by a combined experimental approach of scanning tunneling
microscopy and X-ray absorption spectroscopy that
dysprosium-tris(1,1,1-trifluoro-4-(2-thienyl)-2,4butanedionate) (Dy(tta)$_3$)
complexes deposited on a Au(111) surface undergo a molecular distortion,
resulting in distinct crystal field symmetry imposed on the Dy ion. This leads
to an easy-axis magnetization direction in the ligand plane. Furthermore, we
show that tunneling electrons hardly couple to the spin excitations, which we
ascribe to the shielded nature of the $4f$ electrons.


title:
Is Non-Neutrality Profitable for the Stakeholders of the Internet
  Market?

abstract:
  Net neutrality on the Internet is perceived as the policy that mandates
Internet Service Providers (ISPs) to treat all data equally, regardless of the
source, destination, or type of transmitted data. In this work, we consider a
scheme in which the decision makers of the market are two ISPs, one "big"
Content Provider (CP), and a continuum of end-users. One of the ISPs is neutral
and the other is non-neutral, i.e. she offers a premium quality to a CP in
exchange for a side-payment. In addition, we assume that the CP can
differentiate between ISPs by controlling the quality of the content she is
offering on each one. In this part of the paper, we consider a scenario in
which end-users are not locked in with the ISPs and can switch between ISPs
easily. We formulate a sequential game, and show that there exists a unique
Sub-game Perfect Nash Equilibrium (SPNE) for the game, where the CP pays the
side-payment to the non-neutral ISP and offers her content with the premium
quality. In addition, the CP does not offer her content on the neutral ISP.
Thus, driving this ISP out of the market.


title:
Controllability of a 2D quantum particle in a time-varying disc with
  radial data

abstract:
  In this article we consider a 2-D quantum particle confined a disc whose
radius can be deformed continuously in time. We study the problem of
controllability of such a quantum particle via deformations of the initial
disc, i.e., when we set the time-dependent radius of the disc to be control
variable. We prove that the resulting system is locally controllable around
some radial trajectories which are linear combinations of the first three
radial eigenfunc-tions of the Laplacian in the unit disc with Dirichlet
boundary conditions. We prove this result, thanks to the linearisation
principle, by studying the linearised system, which leads to a moment problem
that can be solved using some results from Nonharmonic Fourier series. In
particular, we have to deal with fine properties of Bessel functions.


title: Planetary nebulae as kinematic tracers of galaxy stellar halos

abstract:
  The kinematic and dynamical properties of galaxy stellar halos are difficult
to measure because of the faint surface brightness that characterizes these
regions. Spiral galaxies can be probed using the radio HI emission; on the
contrary, early-type galaxies contain less gas, therefore alternative kinematic
tracers need to be used. Planetary nebulae (PNe) can be easily detected far out
in the halo thanks to their bright emission lines. It is therefore possible to
map the halo kinematics also in early-type galaxies, typically out to 5
effective radii or beyond. Thanks to the recent spectroscopic surveys targeting
extra-galactic PNe, we can now rely on a few tens of galaxies where the
kinematics of the stellar halos are measured. Here, I will review the main
results obtained in this field in the last decades.


title: Thermal phase transitions of dimensionally continued AdS black holes

abstract:
  We study the thermal phase transitions of charged black holes in
dimensionally continued gravity in anti-de Sitter space. We find the van der
Waals-like phase transition in the temperature-entropy plane of the black holes
with spherical horizons in even dimensions, and there is no such phase
transition of the black holes with flat and hyperbolic geometries. Near the
critical inflection point, the critical exponent is computed and its value does
not depend on the dimension. The Maxwell equal area law is checked to be
fulfilled in the temperature-entropy diagram for the first order phase
transition. In odd dimensions, there are no thermal phase transitions for the
black hole with any geometry of the horizon.


title: POSEidon: Face-from-Depth for Driver Pose Estimation

abstract:
  Fast and accurate upper-body and head pose estimation is a key task for
automatic monitoring of driver attention, a challenging context characterized
by severe illumination changes, occlusions and extreme poses. In this work, we
present a new deep learning framework for head localization and pose estimation
on depth images. The core of the proposal is a regression neural network,
called POSEidon, which is composed of three independent convolutional nets
followed by a fusion layer, specially conceived for understanding the pose by
depth. In addition, to recover the intrinsic value of face appearance for
understanding head position and orientation, we propose a new Face-from-Depth
approach for learning image faces from depth. Results in face reconstruction
are qualitatively impressive. We test the proposed framework on two public
datasets, namely Biwi Kinect Head Pose and ICT-3DHP, and on Pandora, a new
challenging dataset mainly inspired by the automotive setup. Results show that
our method overcomes all recent state-of-art works, running in real time at
more than 30 frames per second.


title: Non-Minimal Quartic Inflation in Supersymmetric SO(10)

abstract:
  We describe how quartic ($\lambda \phi^4$) inflation with non-minimal
coupling to gravity is realized in realistic supersymmetric $SO(10)$ models. In
a well-motivated example the $16-\overline{16}$ Higgs multiplets, which break
$SO(10)$ to $SU(5)$ and yield masses for the right-handed neutrinos, provide
the inflaton field $\phi$. Thus, leptogenesis is a natural outcome in this
class of $SO(10)$ models. Moreover, the adjoint (45-plet) Higgs also acquires a
GUT scale value during inflation so that the monopole problem is evaded. The
scalar spectral index $n_s$ is in good agreement with the observations and $r$,
the tensor to scalar ratio, is predicted for realistic values of GUT parameters
to be of order $10^{-3}-10^{-2}$.


title:
15-Digit Accuracy Calculations of Chandrasekhar's $H$-function for
  Isotropic Scattering by Means of the Double Exponential Formula

abstract:
  This work shows that it is possible to calculate numerical values of the
Chandrasekhar $H$-function for isotropic scattering at least with 15-digit
accuracy by making use of the double exponential formula (DE-formula) of
Takahashi and Mori (Publ. RIMS, Kyoto Univ. Vol. 9, 721, 1974) instead of the
Gauss-Legendre quadrature employed in the numerical scheme of Kawabata and
Limaye (Astrophys. Space Sci. Vol. 332, 365, 2011) and simultaneously taking a
precautionary measure to minimize the effects due to loss of significant digits
particularly in the cases of near-conservative scattering and/or errors
involved in returned values of library functions supplied by compilers in use.
The results of our calculations are presented for 18 selected values of single
scattering albedo $\varpi_0$ and 22 values of an angular variable $\mu$, the
cosine of zenith angle $\theta$ specifying the direction of radiation incident
on or emergent from semi-infinite media.