title:
Getting the Most from Detection of Galactic Supernova Neutrinos in
  Future Large Liquid-Scintillator Detectors

abstract:
  Future large liquid-scintillator detectors can be implemented to observe
neutrinos from a core-collapse supernova (SN) in our galaxy in various reaction
channels: (1) The inverse beta decay $\overline{\nu}^{}_e + p \to n + e^+$; (2)
The elastic neutrino-proton scattering $\nu + p \to \nu + p$; (3) The elastic
neutrino-electron scattering $\nu + e^- \to \nu + e^-$; (4) The charged-current
$\nu^{}_e$ interaction $\nu^{}_e + {^{12}}{\rm C} \to e^- + {^{12}}{\rm N}$;
(5) The charged-current $\overline{\nu}^{}_e$ interaction $\overline{\nu}^{}_e
+ {^{12}}{\rm C} \to e^+ + {^{12}}{\rm B}$; (6) The neutral-current interaction
$\nu + {^{12}}{\rm C} \to \nu + {^{12}}{\rm C}^*$. The less abundant $^{13}{\rm
C}$ atoms in the liquid scintillator are also considered as a target, and both
the charged-current interaction $\nu^{}_e + {^{13}}{\rm C} \to e^- +
{^{13}}{\rm N}$ and the neutral-current interaction $\nu + {^{13}}{\rm C} \to
\nu + {^{13}}{\rm C}^*$ are taken into account. In this work, we show for the
first time that a global analysis of all these channels at a single
{liquid-}scintillator detector, such as Jiangmen Underground Neutrino
Observatory (JUNO), is very important to test the average-energy hierarchy of
SN neutrinos and how the total energy is partitioned among neutrino flavors. In
addition, the dominant channels for reconstructing neutrino spectra and the
impact of other channels are discussed in great detail.


title: Galerkin Spectral Method for the Fractional Nonlocal Thermistor Problem

abstract:
  We develop and analyse a numerical method for the time-fractional nonlocal
thermistor problem. By rigorous proofs, some error estimates in different
contexts are derived, showing that the combination of the backward
differentiation in time and the Galerkin spectral method in space leads, for an
enough smooth solution, to an approximation of exponential convergence in
space.


title: Learning Moore Machines from Input-Output Traces

abstract:
  The problem of learning automata from example traces (but no equivalence or
membership queries) is fundamental in automata learning theory and practice. In
this paper we study this problem for finite state machines with inputs and
outputs, and in particular for Moore machines. We develop three algorithms for
solving this problem: (1) the PTAP algorithm, which transforms a set of
input-output traces into an incomplete Moore machine and then completes the
machine with self-loops; (2) the PRPNI algorithm, which uses the well-known
RPNI algorithm for automata learning to learn a product of automata encoding a
Moore machine; and (3) the MooreMI algorithm, which directly learns a Moore
machine using PTAP extended with state merging. We prove that MooreMI has the
fundamental identification in the limit property. We also compare the
algorithms experimentally in terms of the size of the learned machine and
several notions of accuracy, introduced in this paper. Finally, we compare with
OSTIA, an algorithm that learns a more general class of transducers, and find
that OSTIA generally does not learn a Moore machine, even when fed with a
characteristic sample.


title: Numerical computation of Galois groups

abstract:
  The Galois/monodromy group of a family of geometric problems or equations is
a subtle invariant that encodes the structure of the solutions. Computing
monodromy permutations using numerical algebraic geometry gives information
about the group, but can only determine it when it is the full symmetric group.
We give numerical methods to compute the Galois group and study it when it is
not the full symmetric group. One algorithm computes generators while the other
gives information on its structure as a permutation group. We illustrate these
algorithms with examples using a Macaulay2 package we are developing that
relies upon Bertini to perform monodromy computations.


title: Quantum State Discrimination Using the Minimum Average Number of Copies

abstract:
  In the task of discriminating between nonorthogonal quantum states from
multiple copies, the key parameters are the error probability and the resources
(number of copies) used. Previous studies have considered the task of
minimizing the average error probability for fixed resources. Here we introduce
a new state discrimination task: minimizing the average resources for a fixed
admissible error probability. We show that this new task is not performed
optimally by previously known strategies, and derive and experimentally test a
detection scheme that performs better.


title: Projections for infinitary rewriting

abstract:
  Proof terms in term rewriting are a representation means for reduction
sequences, and more in general for contraction activity, allowing to
distinguish e.g simultaneous from sequential reduction. Proof terms for
finitary, first-order, left-linear term rewriting are described in the Terese
book, chapter 8. In a previous work, we defined an extension of the finitary
proof-term formalism, that allows to describe contractions in infinitary
first-order term rewriting, and gave a characterisation of permutation
equivalence.
  In this work, we discuss how projections of possibly infinite rewrite
sequences can be modeled using proof terms. Again, the foundation is a
characterisation of projections for finitary rewriting described in Terese,
Section 8.7. We extend this characterisation to infinitary rewriting and also
refine it, by describing precisely the role that structural equivalence plays
in the development of the notion of projection. The characterisation we propose
yields a definite expression, i.e. a proof term, that describes the projection
of an infinitary reduction over another.
  To illustrate the working of projections, we show how a common reduct of a
(possibly infinite) reduction and a single step that makes part of it can be
obtained via their respective projections. We show, by means of several
examples, that the proposed definition yields the expected behavior also in
cases beyond those covered by this result. Finally, we discuss how the notion
of limit is used in our definition of projection for infinite reduction.


title:
Using instantaneous frequency and aperiodicity detection to estimate F0
  for high-quality speech synthesis

abstract:
  This paper introduces a general and flexible framework for F0 and
aperiodicity (additive non periodic component) analysis, specifically intended
for high-quality speech synthesis and modification applications. The proposed
framework consists of three subsystems: instantaneous frequency estimator and
initial aperiodicity detector, F0 trajectory tracker, and F0 refinement and
aperiodicity extractor. A preliminary implementation of the proposed framework
substantially outperformed (by a factor of 10 in terms of RMS F0 estimation
error) existing F0 extractors in tracking ability of temporally varying F0
trajectories. The front end aperiodicity detector consists of a complex-valued
wavelet analysis filter with a highly selective temporal and spectral envelope.
This front end aperiodicity detector uses a new measure that quantifies the
deviation from periodicity. The measure is less sensitive to slow FM and AM and
closely correlates with the signal to noise ratio.


title: Recent results in nuclear astrophysics

abstract:
  In this review, we emphasize the interplay between astrophysical
observations, modeling, and nuclear physics laboratory experiments. Several
important nuclear cross sections for astrophysics have long been identified
e.g. 12C(alpha,gamma)16O for stellar evolution, or 13C(alpha,n)16O and
22Ne(alpha,n)25Mg as neutron sources for the s-process. More recently,
observations of lithium abundances in the oldest stars, or of nuclear gamma-ray
lines from space, have required new laboratory experiments. New evaluation of
thermonuclear reaction rates now includes the associated rate uncertainties
that are used in astrophysical models to i) estimate final uncertainties on
nucleosynthesis yields and ii) identify those reactions that require further
experimental investigation. Sometimes direct cross section measurements are
possible, but more generally the use of indirect methods is compulsory in view
of the very low cross sections. Non-thermal processes are often overlooked but
are also important for nuclear astrophysics, e.g. in gamma-ray emission from
solar flares or in the interaction of cosmic rays with matter, and also
motivate laboratory experiments. Finally, we show that beyond the historical
motivations of nuclear astrophysics, understanding i) the energy sources that
drive stellar evolution and ii) the origin of the elements can also be used to
give new insights into physics beyond the standard model.


title:
Probabilistic Numerical Methods for Partial Differential Equations and
  Bayesian Inverse Problems

abstract:
  This paper develops a probabilistic numerical method for solution of partial
differential equations (PDEs) and studies application of that method to
PDE-constrained inverse problems. This approach enables the solution of
challenging inverse problems whilst accounting, in a statistically principled
way, for the impact of discretisation error due to numerical solution of the
PDE. In particular, the approach confers robustness to failure of the numerical
PDE solver, with statistical inferences driven to be more conservative in the
presence of substantial discretisation error. Going further, the problem of
choosing a PDE solver is cast as a problem in the Bayesian design of
experiments, where the aim is to minimise the impact of solver error on
statistical inferences; here the challenge of non-linear PDEs is also
considered. The method is applied to parameter inference problems in which
discretisation error in non-negligible and must be accounted for in order to
reach conclusions that are statistically valid.

categories: stat.ME cs.NA math.NA math.ST stat.CO stat.TH


title: Example of periodic Neumann waveguide with gap in spectrum

abstract:
  In this note we investigate spectral properties of a periodic waveguide
$\Omega^\varepsilon$ ($\varepsilon$ is a small parameter) obtained from a
straight strip by attaching an array of $\varepsilon$-periodically distributed
identical protuberances having "room-and-passage" geometry. In the current work
we consider the operator
$\mathcal{A}^\varepsilon=-\rho^\varepsilon\Delta_{\Omega^\varepsilon}$, where
$\Delta_{\Omega^\varepsilon}$ is the Neumann Laplacian in $\Omega^\varepsilon$,
the weight $\rho^\varepsilon$ is equal to $1$ everywhere except the union of
the "rooms". We will prove that the spectrum of $\mathcal{A}^\varepsilon$ has
at least one gap as $\varepsilon$ is small enough provided certain conditions
on the weight $\rho^\varepsilon$ and the sizes of attached protuberances hold.
  (Dedicated to Pavel Exner's 70th birthday)


title: Detecting the spatial quantum uncertainty of bosonic systems

abstract:
  We present the quantum theory of the measurement of bosonic particles by
multipixel detectors. For the sake of clarity, we specialize on beams of
photons. We study the measurement of different spatial beam characteristics, as
position and width. The limits of these measurements are set by the quantum
nature of the light field. We investigate how both, detector imperfections and
finite pixel size affect the photon counting distribution. An analytic theory
for the discretized measurement scheme is derived. We discuss the results and
compare them to the theory presented by Chille et al. in "Quantum uncertainty
in the beam width of spatial optical modes," Opt. Express 23, 32777 (2015),
which investigates the beam width noise independently of the measurement
system. Finally, we present numerical simulations which furnish realistic and
promising predictions for possible experimental studies.


title: $\lambda-$Symmetries and integrability by quadratures

abstract:
  It is investigated how two (standard or generalized) $\lambda-$symmetries of
a given second-order ordinary differential equation can be used to solve the
equation by quadratures. The method is based on the construction of two
commuting generalized symmetries for this equation by using both
$\lambda-$symmetries. The functions used in that construction are related with
integrating factors of the reduced and auxiliary equations associated to the
$\lambda-$symmetries. These functions can also be used to derive a Jacobi last
multiplier and two integrating factors for the given equation.
  Some examples illustrate the method; one of them is included in the XXVII
case of the Painlev\'e-Gambier classification. An explicit expression of its
general solution in terms of two fundamental sets of solutions for two related
second-order linear equations is also obtained.


title: Theory of cold atoms: Bose-Einstein statistics

abstract:
  This Tutorial is the continuation of the previous tutorial part, published in
Laser Phys. 23, 062001 (2013), where the basic mathematical techniques required
for an accurate description of cold atoms for both types of quantum statistics
are expounded. In the present part, the specifics of the correct theoretical
description of atoms obeying Bose-Einstein statistics are explained, including
trapped Bose atoms. In the theory of systems exhibiting the phenomenon of
Bose-Einstein condensation, there exists a number of delicate mathematical
points, whose misunderstanding often results in principally wrong conclusions.
This is why the consideration in the present Tutorial is sufficiently detailed
in order that the reader could clearly understand the underlying mathematics
and would avoid confusions.


title:
Adsorption geometry and electronic properties of flat-lying monolayers
  of tetracene on the Ag(111) surface

abstract:
  The geometrical and electronic properties of the monolayer (ML) of tetracene
(Tc) molecules on Ag(111) are systematically investigated by means of DFT
calculations with the use of localized basis set. The bridge and hollow
adsorption positions of the molecule in the commensurate $\gamma$-Tc/Ag(111)
are revealed to be the most stable and equally favorable irrespective to the
approximation chosen for the exchange-correlation functional. The binding
energy is entirely determined by the long-range dispersive interaction. The
former lowest unoccupied orbital remains being unoccupied in the case of
$\gamma$-Tc/Ag(111) as well as in the $\alpha$-phase with increased coverage.
The unit cell of the $\alpha$-phase with point-on-line registry was adapted for
calculations based on the available experimental data and the computed
structures of the $\gamma$-phase. The calculated position of the Tc/Ag(111)
interface state is found to be noticeably dependent on the lattice constant of
the substrate, however its energy shift with respect to the Shockley surface
state of the unperturbed clean side of the slab is sensitive only to the
adsorption distance and in good agreement with the experimentally measured
energy shift.


title:
Time reversal method with stabilizing boundary conditions for
  Photoacoustic tomography

abstract:
  We study an inverse initial source problem that models Photoacoustic
tomography measurements with array detectors, and introduce a method that can
be viewed as a modification of the so called back and forth nudging method. We
show that the method converges at an exponential rate under a natural
visibility condition, with data given only on a part of the boundary of the
domain of wave propagation. In this paper we consider the case of noiseless
measurements.


title: Quantum Coherence and Intrinsic Randomness

abstract:
  The peculiar uncertainty or randomness of quantum measurements stems from
coherence, whose information-theoretic characterization is currently under
investigation. Under the resource theory of coherence, it is interesting to
investigate interpretations of coherence measures and the interplay with other
quantum properties, such as quantum correlations and intrinsic randomness.
Coherence can be viewed as the resource for the intrinsic randomness in the
measurement outcomes of a state in the computational basis. We observed in our
previous work that the coherence of formation, which measures the asymptotic
coherence dilution rate, indeed quantifies the uncertainty of a (classical)
correlated party about the system measurement outcome. In this work, we
re-derive the result from a quantum point of view and then connect the
intrinsic randomness to the relative entropy of coherence, another important
coherence measure that quantifies the asymptotic distillable coherence. Even
though there does not exist bound coherent states, these two intrinsic
randomness quantified by coherence of formation and the relative entropy of
coherence are different. Interestingly, we show that this gap is equal to the
quantum discord, a general form of quantum correlations, in the state of the
system of interest and the correlated party, after a local measurement on the
former system.


title:
Efficient High-Speed WPA2 Brute Force Attacks using Scalable Low-Cost
  FPGA Clustering [Extended Version]

abstract:
  WPA2-Personal is widely used to protect Wi-Fi networks against illicit
access. While attackers typically use GPUs to speed up the discovery of weak
network passwords, attacking random passwords is considered to quickly become
infeasible with increasing password length. Professional attackers may thus
turn to commercial high-end FPGA-based cluster solutions to significantly
increase the speed of those attacks. Well known manufacturers such as Elcomsoft
have succeeded in creating world's fastest commercial FPGA-based WPA2 password
recovery system, but since they rely on high-performance FPGAs the costs of
these systems are well beyond the reach of amateurs. In this paper, we present
a highly optimized low-cost FPGA cluster-based WPA-2 Personal password recovery
system that can not only achieve similar performance at a cost affordable by
amateurs, but in comparison our implementation would also be more than 5 times
as fast on the original hardware. Since the currently fastest system is not
only significantly slower but proprietary as well, we believe that we are the
first to present the internals of a highly optimized and fully pipelined FPGA
WPA2 password recovery system. In addition, we evaluated our approach with
respect to performance and power usage and compare it to GPU-based systems. To
assess the real-world impact of our system, we utilized the well known Wigle
Wi-Fi network dataset to conduct a case study within the country and its border
regions. Our results indicate that our system could be used to break into each
of more than 160,000 existing Wi-Fi networks requiring 3 days per network on
our low-cost FPGA cluster in the worst case.


title: Self-organizing structures in immiscible crystals

abstract:
  Spinodal decomposition process in the system of immiscible PbTe/CdTe
compounds is analyzed as an example of a self-organizing structure. The
immiscibility of the constituents leads to the observed morphological
transformations like anisotropy driven formation of quantum dots and nanowires,
and to the phase separation at the highest temperatures. Proposed model
accomplishes bulk and surface diffusion together with the anisotropic mobility
of material components. We analyze its properties by kinetic Monte Carlo
simulations and show that it is able to reproduce all of the structures
observed experimentally in the process of PbTe/CdTe growth. We show that
studied mechanisms of dynamic processes play different role in the creation of
zero--, one--, two-- and finally three-dimensional structures. The shape of
grown structures is different for relatively thick multilayers when bulk
diffusion cooperates with the anisotropic mobility, in annealed structure when
isotropic bulk diffusion only decides about the process and finally for thin
multilayers when surface diffusion is the most decisive factor. We compare our
results with experimentally grown systems and show that proposed model explains
the diversity of observed structures.


title:
A matrix method for fractional Sturm-Liouville problems on bounded
  domain

abstract:
  A matrix method for the solution of direct fractional Sturm-Liouville
problems on bounded domain is proposed where the fractional derivative is
defined in the Riesz sense. The scheme is based on the application of the
Galerkin spectral method of orthogonal polynomials. The order of convergence of
the eigenvalue approximations with respect to the matrix size is studied. Some
numerical examples that confirm the theory and prove the competitiveness of the
approach are finally presented.


title:
Constraining the Nordtvedt parameter with the BepiColombo Radioscience
  experiment

abstract:
  BepiColombo is a joint ESA/JAXA mission to Mercury with challenging
objectives regarding geophysics, geodesy and fundamental physics. The Mercury
Orbiter Radioscience Experiment (MORE) is one of the on-board experiments,
including three different but linked experiments: gravimetry, rotation and
relativity. The aim of the relativity experiment is the measurement of the
post-Newtonian parameters. Thanks to accurate tracking between Earth and
spacecraft, the results are expected to be very precise. However, the outcomes
of the experiment strictly depends on our "knowledge" about solar system:
ephemerides, number of bodies (planets, satellites and asteroids) and their
masses. In this paper we describe a semi-analytic model used to perform a
covariance analysis to quantify the effects, on the relativity experiment, due
to the uncertainties of solar system bodies parameters. In particular, our
attention is focused on the Nordtvedt parameter $\eta$ used to parametrize the
strong equivalence principle violation. After our analysis we estimated
$\sigma[\eta]\lessapprox 4.5\times 10^{-5}$ which is about 1~order of magnitude
larger than the "ideal" case where masses of planets and asteroids have no
errors. The current value, obtained from ground based experiments and lunar
laser ranging measurements, is $\sigma[\eta]\approx 4.4\times 10^{-4}$.
Therefore, we conclude that, even in presence of uncertainties on solar system
parameters, the measurement of $\eta$ by MORE can improve the current precision
of about 1~order of magnitude.


title:
Compensation for geometric modeling errors by electrode movement in
  electrical impedance tomography

abstract:
  Electrical impedance tomography aims at reconstructing the conductivity
inside a physical body from boundary measurements of current and voltage at a
finite number of contact electrodes. In many practical applications, the shape
of the imaged object is subject to considerable uncertainties that render
reconstructing the internal conductivity impossible if they are not taken into
account. This work numerically demonstrates that one can compensate for
inaccurate modeling of the object boundary in two spatial dimensions by
estimating the locations and sizes of the electrodes as a part of a
reconstruction algorithm. The numerical studies, which are based on both
simulated and experimental data, are complemented by proving that the employed
complete electrode model is approximately conformally invariant, which suggests
that the obtained reconstructions in mismodeled domains reflect conformal
images of the true targets. The numerical experiments also confirm that a
similar approach does not, in general, lead to a functional algorithm in three
dimensions.


title: Action Classification via Concepts and Attributes

abstract:
  Classes in natural images tend to follow long tail distributions. This is
problematic when there are insufficient training examples for rare classes.
This effect is emphasized in compound classes, involving the conjunction of
several concepts, such as those appearing in action-recognition datasets. In
this paper, we propose to address this issue by learning how to utilize common
visual concepts which are readily available. We detect the presence of
prominent concepts in images and use them to infer the target labels instead of
using visual features directly, combining tools from vision and
natural-language processing. We validate our method on the recently introduced
HICO dataset reaching a mAP of 31.54\% and on the Stanford-40 Actions dataset,
where the proposed method outperforms that obtained by direct visual features,
obtaining an accuracy 83.12\%. Moreover, the method provides for each class a
semantically meaningful list of keywords and relevant image regions relating it
to its constituent concepts.


title:
Chemical complexity in protoplanetary disks in the era of ALMA and
  Rosetta

abstract:
  Comets provide a unique insight into the molecular composition and complexity
of the material in the primordial solar nebula. Recent results from the Rosetta
mission, currently monitoring comet 67P/Churyumov-Gerasimenko in situ, and ALMA
(the Atacama Large Millimeter/submillimeter Array), have demonstrated a
tantalising link between the chemical complexity now confirmed in disks (via
the detection of gas-phase CH3CN; Oberg et al. 2015) and that confirmed on the
surface of 67P (Goesmann et al. 2015), raising questions concerning the
chemical origin of such species (cloud or inheritance versus disk synthesis).
Results from an astrochemical model of a protoplanetary disk are presented in
which complex chemistry is included and in which it is assumed that simple ices
only are inherited from the parent molecular cloud. The model results show good
agreement with the abundances of several COMs observed on the surface of 67P
with Philae/COSAC. Cosmic-ray and X-ray-induced photoprocessing of
predominantly simple ices inherited by the protoplanetary disk is sufficient to
generate a chemical complexity similar to that observed in comets. This
indicates that the icy COMs detected on the surface of 67P may have a disk
origin. The results also show that gas-phase CH3CN is abundant in the inner
warm disk atmosphere where hot gas-phase chemistry dominates and potentially
erases the ice chemical signature. Hence, CH3CN may not be an unambiguous
tracer of the complex organic ice reservoir. However, a better understanding of
the hot gas-phase chemistry of CH3CN is needed to confirm this preliminary
conclusion.


title: Asymptotically exact inference in differentiable generative models

abstract:
  Many generative models can be expressed as a differentiable function of
random inputs drawn from some simple probability density. This framework
includes both deep generative architectures such as Variational Autoencoders
and a large class of procedurally defined simulator models. We present a method
for performing efficient MCMC inference in such models when conditioning on
observations of the model output. For some models this offers an asymptotically
exact inference method where Approximate Bayesian Computation might otherwise
be employed. We use the intuition that inference corresponds to integrating a
density across the manifold corresponding to the set of inputs consistent with
the observed outputs. This motivates the use of a constrained variant of
Hamiltonian Monte Carlo which leverages the smooth geometry of the manifold to
coherently move between inputs exactly consistent with observations. We
validate the method by performing inference tasks in a diverse set of models.


title:
Minimum-weight codewords of the Hermitian codes are supported on
  complete intersections

abstract:
  Let $\mathcal{H}$ be the Hermitian curve defined over a finite field
$\mathbb{F}_{q^2}$. In this paper we complete the geometrical characterization
of the supports of the minimum-weight codewords of the algebraic-geometry codes
over $\mathcal{H}$, started in [1]: if $d$ is the distance of the code, the
supports are all the sets of $d$ distinct $\mathbb{F}_{q^2}$-points on
$\mathcal{H}$ complete intersection of two curves defined by polynomials with
prescribed initial monomials w.r.t. \texttt{DegRevLex}.
  For most Hermitian codes, and especially for all those with distance $d\geq
q^2-q$ studied in [1], one of the two curves is always the Hermitian curve
$\mathcal{H}$ itself, while if $d<q$ the supports are complete intersection of
two curves none of which can be $\mathcal{H}$.
  Finally, for some special codes among those with intermediate distance
between $q$ and $q^2-q$, both possibilities occur.
  We provide simple and explicit numerical criteria that allow to decide for
each code what kind of supports its minimum-weight codewords have and to obtain
a parametric description of the family (or the two families) of the supports.
  [1] C. Marcolla and M. Roggero, Hermitian codes and complete intersections,
arXiv preprint arXiv:1510.03670 (2015).


title: Linear theory of random textures of 3He-A in aerogel

abstract:
  Spacial variation of the orbital part of the order parameter of $^3$He-A in
aerogel is represented as a random walk of the unit vector $\mathbf{l}$ in a
field of random anisotropy produced by the strands of aerogel. For a range of
distances, where variation of $\mathbf{l}$ is small in comparison with its
absolute value correlation function of directions of $\mathbf{l}(\mathbf{r})$
is expressed in terms of the correlation function of the random anisotropy
field. With simplifying assumptions about this correlation function a spatial
dependence of the average variation $\langle\delta\mathbf{l}^2\rangle$ is found
analytically for isotropic and axially anisotropic aerogels. Average
projections of $\mathbf{l}$ on the axes of anisotropy are expressed in terms of
characteristic parameters of the problem. Within the "model of random
cylinders" numerical estimations of characteristic length for disruption of the
long-range order and of the critical anisotropy for restoration of this order
are made and compared with other estimations .


title: As-exact-as-possible repair of unprintable STL files

abstract:
  Purpose: The class of models that can be represented by STL files is larger
than the class of models that can be printed using additive manufacturing
technologies. Stated differently, there exist well-formed STL files that cannot
be printed. In this paper such a gap is formalized and a fully automatic
procedure is described to turn any such file into a printable model.
  Approach: Based on well-established concepts from combinatorial topology, we
provide an unambiguous description of all the mathematical entities involved in
the modeling-printing pipeline. Specifically, we formally define the conditions
that an STL file must satisfy to be printable and, based on these, we design an
as-exact-as-possible repairing algorithm.
  Findings: We have found that, in order to cope with all the possible triangle
configurations, the algorithm must distinguish between triangles that bound
solid parts and triangles that constitute zero-thickness sheets. Only the
former set can be fixed without distortion.
  Originality: Previous methods that are guaranteed to fix all the possible
configurations provide only approximate solutions with an unnecessary
distortion. Conversely, our procedure is as exact as possible, meaning that no
visible distortion is introduced unless it is strictly imposed by limitations
of the printing device. Thanks to such an unprecedented flexibility and
accuracy, this algorithm is expected to significantly simplify the
modeling-printing process, in particular within the continuously emerging
non-professional "maker" communities.


title:
Derivative-based global sensitivity measures and their link with Sobol
  sensitivity indices

abstract:
  The variance-based method of Sobol sensitivity indices is very popular among
practitioners due to its efficiency and easiness of interpretation. However,
for high-dimensional models the direct application of this method can be very
time consuming and prohibitively expensive to use. One of the alternative
global sensitivity analysis methods known as the method of derivative based
global sensitivity measures (DGSM) has recently become popular among
practitioners. It has a link with the Morris screening method and Sobol
sensitivity indices. DGSM are very easy to implement and evaluate numerically.
The computational time required for numerical evaluation of DGSM is generally
much lower than that for estimation of Sobol sensitivity indices. We present a
survey of recent advances in DGSM and new results concerning new lower and
upper bounds on the values of Sobol total sensitivity indices. Using these
bounds it is possible in most cases to get a good practical estimation of the
values of Sobol total sensitivity indices. Several examples are used to
illustrate an application of DGSM.


title:
Theory of single and two-qubit operations with donor-bound electron
  spins in germanium

abstract:
  The possibility of quantum computing with spins in germanium nanoscale
transistors has recently attracted interest since it promises highly tuneable
qubits that have encouraging coherence times. We here present the first
complete theory of the orbital states of Ge donor electrons, and use it to show
that Ge could have significant advantages over silicon in the implementation of
a donor-based quantum processor architecture. We show that the stronger
spin-orbit interaction and the larger electron donor wave functions for Ge
donors allow for greater tuning of the single qubit energy than for those in Si
crystals, thus enabling a large speedup of selective (local) quantum gates.
Further, exchange coupling between neighboring donor qubits is shown to be much
larger in Ge than in Si, and we show that this greatly relaxes the precision in
donor placement needed for robust two-qubit gates. To do this we compare two
statistical distributions for Ge:P and Si:P pair couplings, corresponding to
realistic donor implantation misplacement, and find that the spin couplings in
Ge:P have a $33\%$ chance of being within an order of magnitude of the largest
coupling, compared with only $10\%$ for the Si:P donors. This allows fast,
parallel and robust architectures for quantum computing with donors in Ge.


title: Antistrong digraphs

abstract:
  An antidirected trail in a digraph is a trail (a walk with no arc repeated)
in which the arcs alternate between forward and backward arcs. An antidirected
path is an antidirected trail where no vertex is repeated. We show that it is
NP-complete to decide whether two vertices $x,y$ in a digraph are connected by
an antidirected path, while one can decide in linear time whether they are
connected by an antidirected trail. A digraph $D$ is antistrong if it contains
an antidirected $(x,y)$-trail starting and ending with a forward arc for every
choice of $x,y\in V(D)$. We show that antistrong connectivity can be decided in
linear time. We discuss relations between antistrong connectivity and other
properties of a digraph and show that the arc-minimal antistrong spanning
subgraphs of a digraph are the bases of a matroid on its arc-set. We show that
one can determine in polynomial time the minimum number of new arcs whose
addition to $D$ makes the resulting digraph the arc-disjoint union of $k$
antistrong digraphs. In particular, we determine the minimum number of new arcs
which need to be added to a digraph to make it antistrong. We use results from
matroid theory to characterize graphs which have an antistrong orientation and
give a polynomial time algorithm for constructing such an orientation when it
exists. This immediately gives analogous results for graphs which have a
connected bipartite 2-detachment. Finally, we study arc-decompositions of
antistrong digraphs and pose several problems and conjectures.


title: Effective Blind Source Separation Based on the Adam Algorithm

abstract:
  In this paper, we derive a modified InfoMax algorithm for the solution of
Blind Signal Separation (BSS) problems by using advanced stochastic methods.
The proposed approach is based on a novel stochastic optimization approach
known as the Adaptive Moment Estimation (Adam) algorithm. The proposed BSS
solution can benefit from the excellent properties of the Adam approach. In
order to derive the new learning rule, the Adam algorithm is introduced in the
derivation of the cost function maximization in the standard InfoMax algorithm.
The natural gradient adaptation is also considered. Finally, some experimental
results show the effectiveness of the proposed approach.


title:
Dynamic analysis of simultaneous adaptation of force, impedance and
  trajectory

abstract:
  When carrying out tasks in contact with the environment, humans are found to
concurrently adapt force, impedance and trajectory. Here we develop a robotic
model of this mechanism in humans and analyse the underlying dynamics. We
derive a general adaptive controller for the interaction of a robot with an
environment solely characterised by its stiffness and damping, using Lyapunov
theory.


title: The electroweak theory based on SU(4)_L X U(1)_X gauge group

abstract:
  This paper includes two main parts. In the first part, we present generalized
gauge models based on SU(3)_C x SU(4)_L x U(1)_X (3-4-1) gauge group with
arbitrary electric charge of leptons. The mixing matrix of neutral gauge bosons
is analysed, the eigenmasses and eigenstates are obtained. The anomaly free as
well as matching conditions are discussed precisely. In the second part, we
present new development of the original 3-4-1 model [1,2]. In difference from
previous works, in this paper the neutrinos, with the help of the decuplet H,
get the Dirac masses at the tree level. The VEV of the Higgs field in the
decuplet H acquiring VEV responsible for neutrino Dirac mass leads to mixing in
separated pairs of singly charged gauge bosons, namely the SM W boson and K -
new gauge boson acting in right-handed lepton sector, and the singly charged
bileptons X and Y. Due to the mixing, there occurs a right-handed current
carried by the SM W bosons. From the expression of the electromagnetic coupling
constant, ones get the limit of square sinus of the Weinberg angle: sin^2
\theta_W < 0.25 and a constraint on electric charges of extra leptons. In the
limit of lepton number conservation, the Higgs sector contains all massless
Goldstone bosons for massive gauge bosons and the SM-like Higgs. Some
phenomenology are pointed out.


title:
Phase structure of the $O(2)$ ghost model with higher-order gradient
  term

abstract:
  The phase structure and the infrared behaviour of the Euclidean 3-dimensional
$O(2)$ symmetric ghost scalar field model with higher-order derivative term has
been investigated in Wegner and Houghton's renormalization group framework. The
symmetric phase in which no ghost condensation occurs and the phase with
restored symmetry but with a transient presence of a ghost condensate have been
identified. Finiteness of the correlation length at the phase boundary hints to
a phase transition of first order. The results are compared with those for the
ordinary $O(2)$ symmetric scalar field model.


title:
Hecke algebra with respect to the pro-$p$-radical of a maximal compact
  open subgroup for $GL(n,F)$ and its inner forms

abstract:
  Let $G$ be a direct product of inner forms of general linear groups over
non-archimedean locally compact fields of residue characteristic $p$ and let
$K^1$ be the pro-$p$-radical of a maximal compact open subgroup of $G$. In this
paper we describe the (intertwining) Hecke algebra $\mathscr{H}(G,K^1)$, that
is the convolution $\mathbb{Z}$-algebra of functions from $G$ to $\mathbb{Z}$
that are bi-invariant for $K^1$ and whose supports are a finite union of
$K^1$-double cosets. We produce a presentation by generators and relations of
this algebra. Finally we prove that the level-$0$ subcategory of the category
of smooth representations of $G$ over a unitary commutative ring $R$ such that
$p\in R^{\times}$ is equivalent to the category of modules over
$\mathscr{H}(G,K^1)\otimes_\mathbb{Z} R$.


title: Decoherence and noise in open quantum system dynamics

abstract:
  We consider the description of quantum noise within the framework of the
standard Copenhagen interpretation of quantum mechanics applied to a composite
system environment setting. Averaging over the environmental degrees of freedom
leads to a stochastic quantum dynamics, described by equations complying with
the constraints arising from the statistical structure of quantum mechanics.
Simple examples are considered in the framework of open system dynamics
described within a master equation approach, pointing in particular to the
appearance of the phenomenon of decoherence and to the relevance of quantum
correlation functions of the environment in the determination of the action of
quantum noise.


title: Loewner chains with quasiconformal extensions: an approximation approach

abstract:
  A new approach in Loewner Theory proposed by Bracci, Contreras,
D\'iaz-Madrigal and Gumenyuk provides a unified treatment of the radial and the
chordal versions of the Loewner equations. In this framework, a generalized
Loewner chain satisfies the differential equation $$ \partial_{t}f_{t}(z) = (z
- \tau(t))(1-\overline{\tau(t)}z)\partial_{z}f_{t}(z)p(z,t), $$ where $\tau :
[0,\infty) \to \overline{\mathbb{D}}$ is measurable and $p$ is called a
Herglotz function. In this paper, we will show that if there exists a $k \in
[0,1)$ such that $p$ satisfies $$ |p(z,t) - 1| \leq k |p(z,t) + 1| $$ for all
$z \in \mathbb{D}$ and almost all $t \in [0,\infty)$, then $f_{t}$ has a
$k$-quasiconformal extension to the whole Riemann sphere for all $t \in
[0,\infty)$. The radial case ($\tau =0$) and the chordal case ($\tau=1$) have
been proven by Becker [J. Reine Angew. Math. \textbf{255} (1972), 23-43] and
Gumenyuk and the author (Math. Z. \textbf{285} (2017), no.3, 1063--1089). In
our theorem, no superfluous assumption is imposed on $\tau \in
\overline{\mathbb{D}}$. As a key foundation of our proof is an approximation
method using the continuous dependence of evolution families.


title: Mid-infrared vibrational study of deuterium-containing PAH variants

abstract:
  Polycyclic Aromatic Hydrocarbon (PAH) molecules have been long proposed to be
a major carrier of 'Unidentified Infrared' (UIR) emission bands that have been
observed ubiquitously in various astrophysical environments. These molecules
can potentially be an efficient reservoir of deuterium. Once the infrared
properties of the deuterium- containing PAHs are well understood both
experimentally and theoretically, the interstellar UIR bands can be used as a
valuable tool to infer the cause of the deuterium depletion in the ISM.
  Density Functional Theory (DFT) calculations have been carried out on
deuterium-containing ovalene variants to study the infrared properties of these
molecules. These include deuterated ovalene, cationic deuterated ovalene,
deuteronated ovalene and deuterated-deuteronated ovalene. We present a D/H
ratio calculated from our theoretical study to compare with the observationally
proposed D/H ratio.


title:
Streaming potential modeling in fractured rock: Insights into the
  identification of hydraulically active fractures

abstract:
  Numerous field experiments suggest that the self-potential (SP) geophysical
method may allow for the detection of hydraulically active fractures and
provide information about fracture properties. However, a lack of suitable
numerical tools for modeling streaming potentials in fractured media prevents
quantitative interpretation and limits our understanding of how the SP method
can be used in this regard. To address this issue, we present a highly
efficient two-dimensional discrete-dual-porosity approach for solving the fluid
flow and associated self-potential problems in fractured rock. Our approach is
specifically designed for complex fracture networks that cannot be investigated
using standard numerical methods. We then simulate SP signals associated with
pumping conditions for a number of examples to show that (i) accounting for
matrix fluid flow is essential for accurate SP modeling and (ii) the
sensitivity of SP to hydraulically active fractures is intimately linked with
fracture-matrix fluid interactions. This implies that fractures associated with
strong SP amplitudes are likely to be hydraulically conductive, attracting
fluid flow from the surrounding matrix.


title: Slow blue nuclear hypervariables in PanSTARRS-1

abstract:
  We discuss 76 large amplitude transients (Delta-m>1.5) occurring in the
nuclei of galaxies, nearly all with no previously known Active Galactic Nucleus
(AGN). They have been discovered as part of the Pan-STARRS1 (PS1) 3pi survey,
by comparison with SDSS photometry a decade earlier, and then monitored with
the Liverpool Telescope, and studied spectroscopically with the William
Herschel Telescope (WHT). Based on colours, light curve shape, and spectra,
these transients fall into four groups. A few are misclassified stars or
objects of unknown type. Some are red/fast transients and are known or likely
nuclear supernovae. A few are either radio sources or erratic variables and so
likely blazars. However the majority (~66%) are blue and evolve slowly, on a
timescale of years. Spectroscopy shows them to be AGN at z~ 0.3 - 1.4, which
must have brightened since the SDSS photometry by around an order of magnitude.
It is likely that these objects were in fact AGN a decade ago, but too weak to
be recognised by SDSS; they could then be classed as "hypervariable" AGN. By
searching the SDSS Stripe 82 quasar database, we find 15 similar objects. We
discuss several possible explanations for these slow blue hypervariables - (i)
unusually luminous tidal disruption events; (ii) extinction events; (iii)
changes in accretion state; and (iv) large amplitude microlensing by stars in
foreground galaxies. A mixture of explanations (iii) and (iv) seems most
likely. Both hold promise of considerable new insight into the AGN phenomenon.


title:
Unsupervised Word and Dependency Path Embeddings for Aspect Term
  Extraction

abstract:
  In this paper, we develop a novel approach to aspect term extraction based on
unsupervised learning of distributed representations of words and dependency
paths. The basic idea is to connect two words (w1 and w2) with the dependency
path (r) between them in the embedding space. Specifically, our method
optimizes the objective w1 + r = w2 in the low-dimensional space, where the
multi-hop dependency paths are treated as a sequence of grammatical relations
and modeled by a recurrent neural network. Then, we design the embedding
features that consider linear context and dependency context information, for
the conditional random field (CRF) based aspect term extraction. Experimental
results on the SemEval datasets show that, (1) with only embedding features, we
can achieve state-of-the-art results; (2) our embedding method which
incorporates the syntactic information among words yields better performance
than other representative ones in aspect term extraction.


title:
Dimension Projection among Languages based on Pseudo-relevant Documents
  for Query Translation

abstract:
  Using top-ranked documents in response to a query has been shown to be an
effective approach to improve the quality of query translation in
dictionary-based cross-language information retrieval. In this paper, we
propose a new method for dictionary-based query translation based on dimension
projection of embedded vectors from the pseudo-relevant documents in the source
language to their equivalents in the target language. To this end, first we
learn low-dimensional vectors of the words in the pseudo-relevant collections
separately and then aim to find a query-dependent transformation matrix between
the vectors of translation pairs appeared in the collections. At the next step,
representation of each query term is projected to the target language and then,
after using a softmax function, a query-dependent translation model is built.
Finally, the model is used for query translation. Our experiments on four CLEF
collections in French, Spanish, German, and Italian demonstrate that the
proposed method outperforms a word embedding baseline based on bilingual
shuffling and a further number of competitive baselines. The proposed method
reaches up to 87% performance of machine translation (MT) in short queries and
considerable improvements in verbose queries.


title:
On the topological pressure of the saturated set with non-uniform
  structure

abstract:
  We derive a conditional variational principle of the saturated set for
systems with the non-uniform structure. Our result applies to a broad class of
systems including beta-shifts, S-gap shifts and their factors.


title:
Deep GeMS/GSAOI near-infrared observations of N159W in the Large
  Magellanic Cloud

abstract:
  Aims. The formation and properties of star clusters at the edge of H II
regions are poorly known, partly due to limitations in angular resolution and
sensitivity, which become particularly critical when dealing with extragalactic
clusters. In this paper we study the stellar content and star-formation
processes in the young N159W region in the Large Magellanic Cloud.
  Methods. We investigate the star-forming sites in N159W at unprecedented
spatial resolution using JHKs-band images obtained with the GeMS/GSAOI
instrument on the Gemini South telescope. The typical angular resolution of the
images is of 100 mas, with a limiting magnitude in H of 22 mag (90 percent
completeness). Photometry from our images is used to identify candidate young
stellar objects (YSOs) in N159W. We also determine the H-band luminosity
function of the star cluster at the centre of the H II region and use this to
estimate its initial mass function (IMF).
  Results. We estimate an age of 2 + or - 1 Myr for the central cluster, with
its IMF described by a power-law with an index of gamma = - 1.05 + or - 0.2 ,
and with a total estimated mass of 1300 solar mass. We also identify 104
candidate YSOs, which are concentrated in clumps and subclusters of stars,
principally at the edges of the H II region. These clusters display signs of
recent and active star-formation such as ultra-compact H II regions, and
molecular outflows. This suggests that the YSOs are typically younger than the
central cluster, pointing to sequential star-formation in N159W, which has
probably been influenced by interactions with the expanding H II bubble.


title:
Investigation into spiral phase plate contrast in optical and electron
  microscopy

abstract:
  The use of phase plates in the back focal plane of a microscope is a well
established technique in optical microscopy to increase the contrast of weakly
interacting samples and is gaining interest in electron microscopy as well. In
this paper we study the spiral phase plate (SPP), also called helical, vortex,
or two-dimensional Hilbert phase plate, that adds an angularly dependent phase
of the form $e^{i\ell\phi}$ to the exit wave in Fourier space. In the limit of
large collection angles, we analytically calculate that the average of a pair
of $\ell=\pm1$ SPP images is directly proportional to the gradient squared of
the exit wave, explaining the edge contrast previously seen in optical SPP
work. The difference between a clockwise-anticlockwise pair of SPP images and
conditions where this difference vanishes and the gradient of the exit wave can
be seen from one single SPP image, are discussed. Finally, we demonstrate how
with three images, one without and one with each of an $\ell=\pm1$ SPP, may
give enough information to reconstruct both the amplitude and the phase of the
exit wave. This work provides the theoretical background to interpret images
obtained with a SPP and can help enable new experiments to study for example
magnetic materials in an electron microscope.


title: Quantum Field Theory Applications of Heun Type Functions

abstract:
  After a brief introduction to Heun type functions we note that the actual
solutions of the eigenvalue equation emerging in the calculation of the one
loop contribution to QCD from the Belavin-Polyakov-Schwarz-Tyupkin instanton
and the similar calculation for a Dirac particle coupled to a scalar $CP^1$
model in two dimensions can be given in terms of confluent Heun equation in
their original forms. These equations were previously modified to be solved by
more elementary functions. We also show that polynomial solutions with discrete
eigenvalues are impossible to find in the unmodified equations.


title:
Confinement/deconfinement transition from symmetry breaking in
  gauge/gravity duality

abstract:
  We study the confinement/deconfinement transition in a strongly coupled
system triggered by an independent symmetry-breaking quantum phase transition
in gauge/gravity duality. The gravity dual is an Einstein-scalar-dilaton system
with AdS near-boundary behavior and soft wall interior at zero scalar
condensate. We study the cases of neutral and charged condensate separately. In
the former case the condensation breaks the discrete $\mathbb{Z}_2$ symmetry
while a charged condensate breaks the continuous $U(1)$ symmetry. After the
condensation of the order parameter, the non-zero vacuum expectation value of
the scalar couples to the dilaton, changing the soft wall geometry into a
non-confining and anisotropically scale-invariant infrared metric. In other
words, the formation of long-range order is immediately followed by the
deconfinement transition and the two critical points coincide. The confined
phase has a scale -- the confinement scale (energy gap) which vanishes in the
deconfined case. Therefore, the breaking of the symmetry of the scalar
($\mathbb{Z}_2$ or $U(1)$) in turn restores the scaling symmetry in the system
and neither phase has a higher overall symmetry than the other. When the scalar
is charged the phase transition is continuous which goes against the
Ginzburg-Landau theory where such transitions generically only occur
discontinuously. This phenomenon has some commonalities with the scenario of
deconfined criticality. The mechanism we have found has applications mainly in
effective field theories such as quantum magnetic systems. We briefly discuss
these applications and the relation to real-world systems.


title:
Exploring the ferromagnetic behaviour of a repulsive Fermi gas via spin
  dynamics

abstract:
  Ferromagnetism is a manifestation of strong repulsive interactions between
itinerant fermions in condensed matter. Whether short-ranged repulsion alone is
sufficient to stabilize ferromagnetic correlations in the absence of other
effects, like peculiar band dispersions or orbital couplings, is however
unclear. Here, we investigate ferromagnetism in the minimal framework of an
ultracold Fermi gas with short-range repulsive interactions tuned via a
Feshbach resonance. While fermion pairing characterises the ground state, our
experiments provide signatures suggestive of a metastable Stoner-like
ferromagnetic phase supported by strong repulsion in excited scattering states.
We probe the collective spin response of a two-spin mixture engineered in a
magnetic domain-wall-like configuration, and reveal a substantial increase of
spin susceptibility while approaching a critical repulsion strength. Beyond
this value, we observe the emergence of a time-window of domain immiscibility,
indicating the metastability of the initial ferromagnetic state. Our findings
establish an important connection between dynamical and equilibrium properties
of strongly-correlated Fermi gases, pointing to the existence of a
ferromagnetic instability.


title: Parton Shower Matching Systematics in Vector-Boson-Fusion WW Production

abstract:
  We perform a detailed analysis of next-to-leading order plus parton-shower
matching in vector-boson-fusion WW production including leptonic decays. The
study is performed in the Herwig 7 framework interfaced to VBFNLO 3, using the
angular-ordered and dipole-based parton-shower algorithms combined with the
subtractive and multiplicative matching algorithms.


title: SS4MCT: A Statistical Stemmer for Morphologically Complex Texts

abstract:
  There have been multiple attempts to resolve various inflection matching
problems in information retrieval. Stemming is a common approach to this end.
Among many techniques for stemming, statistical stemming has been shown to be
effective in a number of languages, particularly highly inflected languages. In
this paper we propose a method for finding affixes in different positions of a
word. Common statistical techniques heavily rely on string similarity in terms
of prefix and suffix matching. Since infixes are common in irregular/informal
inflections in morphologically complex texts, it is required to find infixes
for stemming. In this paper we propose a method whose aim is to find
statistical inflectional rules based on minimum edit distance table of word
pairs and the likelihoods of the rules in a language. These rules are used to
statistically stem words and can be used in different text mining tasks.
Experimental results on CLEF 2008 and CLEF 2009 English-Persian CLIR tasks
indicate that the proposed method significantly outperforms all the baselines
in terms of MAP.


title:
Thinning, photonic beamsplitting, and a general discrete entropy power
  inequality

abstract:
  Many partially-successful attempts have been made to find the most natural
discrete-variable version of Shannon's entropy power inequality (EPI). We
develop an axiomatic framework from which we deduce the natural form of a
discrete-variable EPI and an associated entropic monotonicity in a
discrete-variable central limit theorem. In this discrete EPI, the geometric
distribution, which has the maximum entropy among all discrete distributions
with a given mean, assumes a role analogous to the Gaussian distribution in
Shannon's EPI. The entropy power of $X$ is defined as the mean of a geometric
random variable with entropy $H(X)$. The crux of our construction is a
discrete-variable version of Lieb's scaled addition $X \boxplus_\eta Y$ of two
discrete random variables $X$ and $Y$ with $\eta \in (0, 1)$. We discuss the
relationship of our discrete EPI with recent work of Yu and Johnson who
developed an EPI for a restricted class of random variables that have
ultra-log-concave (ULC) distributions. Even though we leave open the proof of
the aforesaid natural form of the discrete EPI, we show that this discrete EPI
holds true for variables with arbitrary discrete distributions when the entropy
power is redefined as $e^{H(X)}$ in analogy with the continuous version.
Finally, we show that our conjectured discrete EPI is a special case of the
yet-unproven Entropy Photon-number Inequality (EPnI), which assumes a role
analogous to Shannon's EPI in capacity proofs for Gaussian bosonic (quantum)
channels.


title:
Asymptotic normality of the likelihood moment estimators for a
  stationary linear process with heavy-tailed innovations

abstract:
  A variety of estimators for the parameters of the Generalized Pareto
distribution, the approximating distribution for excesses over a high
threshold, have been proposed, always assuming the underlying data to be
independent. We recently proved that the likelihood moment estimators are
consistent estimators for the parameters of the Generalized Pareto distribution
for the case where the underlying data arises from a (stationary) linear
process with heavy-tailed innovations. In this paper we derive the bivariate
asymptotic normality under some additional assumptions and give an explicit
example on how to check these conditions by using asymptotic expansions.


title:
Topological insulator on honeycomb lattices and ribbons without
  inversion symmetry

abstract:
  We study the Kane-Mele-Hubbard model with an additional
inversion-symmetry-breaking term. Using the topological Hamiltonian approach,
we calculate the $\mathbb{Z}_2$ invariant of the system as function of
spin-orbit coupling, Hubbard interaction $U$, and inversion-symmetry-breaking
on-site potential. The phase diagram calculated in that way shows that, on the
one hand, a large term of the latter kind destroys the topological non-trivial
state. On the other hand, however, this inversion-symmetry-breaking field can
enhance the topological state, since for moderate values the transition from
the non-trivial topological to the trivial Mott insulator is pushed to larger
values of interaction $U$. This feature of an enhanced topological state is
also found on honeycomb ribbons. With inversion symmetry, the edge of the
zigzag ribbon is magnetic for any value of $U$. This magnetic moment destroys
the gapless edge mode. Lifting inversion symmetry allows for a finite region in
interaction strength $U$ below which gapless edge modes exist.


title: Counting rational points on smooth cubic curves

abstract:
  We use a global version of Heath-Brown's $p-$adic determinant method
developed by Salberger to give upper bounds for the number of rational points
of height at most $B$ on non-singular cubic curves defined over $\mathbb{Q}$.
The bounds are uniform in the sense that they only depend on the rank of the
corresponding Jacobian.


title:
Directional Fano Resonances at Light Scattering by a High Refractive
  Index Dielectric Sphere

abstract:
  In this research, we report the experimental evidence of the directional Fano
resonances at the scattering of a plane, linearly polarized electromagnetic
wave by a homogeneous dielectric sphere with high refractive index and low
losses. We observe a typical asymmetric Fano profile for the intensity
scattered in, practically, any given direction, while the overall extinction
cross section remains Lorentzian. The phenomenon is originated in the
interference of the selectively excited electric dipolar and quadrupolar modes.
The selectivity of the excitation is achieved by the proper choice of the
frequency of the incident wave. Thanks to the scaling invariance of the Maxwell
equations, in these experiments we mimic the scattering of the visible and near
IR radiation by a nanoparticle made of common superconductor materials (Si, Ge,
GaAs, GaP) by the equivalent scattering of a spherical particle of 18 mm in
diameter in the microwave range. The theory developed to explain the
experiments extends the conventional Fano approach to the case when both
interfering partitions are resonant. The perfect agreement between the
experiment and the theory is demonstrated.


title:
Femtosecond dynamics of correlated many-body states in C$_{60}$
  fullerenes

abstract:
  Fullerene complexes may play a key role in the design of future molecular
electronics and nanostructured devices with potential applications in light
harvesting using organic solar cells. Charge and energy flow in these systems
is mediated by many-body effects. We studied the structure and dynamics of
laser-induced multi-electron excitations in isolated C$_{60}$ by two-photon
photoionization as a function of excitation wavelength using a tunable fs UV
laser and developed a corresponding theoretical framework on the basis of
\emph{ab initio} calculations. The measured resonance line width gives direct
information on the excited state lifetime. From the spectral deconvolution we
derive a lower limit for purely electronic relaxation on the order of
$\tau_\mathrm{el}=10^{+5}_{-3}$ fs. Energy dissipation towards nuclear degrees
of freedom is studied in time-resolved techniques. The evaluation of the
non-linear autocorrelation trace gives a characteristic time constant of
$\tau_\mathrm{vib}=400\pm100$ fs for the exponential decay. In line with the
experiment, the observed transient dynamics is explained theoretically by
nonadiabatic (vibronic) couplings involving the correlated electronic, the
nuclear degrees of freedom (accounting for the Herzberg-Teller coupling), and
their interplay.


title: How Many Real Attractive Fixed Points Can A Polynomial Have?

abstract:
  We prove a complex polynomial of degree $n$ has at most $\lceil n/2 \rceil$
attractive fixed points lying on a line. We also consider the general case.


title: Anisotropic curvature flow of immersed curves

abstract:
  We prove short-time existence of {\phi}-regular solutions to the anisotropic
and crystalline curvature flow of immersed planar curves.


title:
Consensus in the Presence of Multiple Opinion Leaders: Effect of Bounded
  Confidence

abstract:
  The problem of analyzing the performance of networked agents exchanging
evidence in a dynamic network has recently grown in importance. This problem
has relevance in signal and data fusion network applications and in studying
opinion and consensus dynamics in social networks. Due to its capability of
handling a wider variety of uncertainties and ambiguities associated with
evidence, we use the framework of Dempster-Shafer (DS) theory to capture the
opinion of an agent. We then examine the consensus among agents in dynamic
networks in which an agent can utilize either a cautious or receptive updating
strategy. In particular, we examine the case of bounded confidence updating
where an agent exchanges its opinion only with neighboring nodes possessing
'similar' evidence. In a fusion network, this captures the case in which nodes
only update their state based on evidence consistent with the node's own
evidence. In opinion dynamics, this captures the notions of Social Judgment
Theory (SJT) in which agents update their opinions only with other agents
possessing opinions closer to their own. Focusing on the two special DS
theoretic cases where an agent state is modeled as a Dirichlet body of evidence
and a probability mass function (p.m.f.), we utilize results from matrix
theory, graph theory, and networks to prove the existence of consensus agent
states in several time-varying network cases of interest. For example, we show
the existence of a consensus in which a subset of network nodes achieves a
consensus that is adopted by follower network nodes. Of particular interest is
the case of multiple opinion leaders, where we show that the agents do not
reach a consensus in general, but rather converge to 'opinion clusters'.
Simulation results are provided to illustrate the main results.


title: Givental-type reconstruction at a non-semisimple point

abstract:
  In this paper we consider the orbifold curve, which is a quotient of an
elliptic curve $\mathcal{E}$ by a cyclic group of order 4. We develop a
systematic way to obtain a Givental-type reconstruction of Gromov-Witten theory
of the orbifold curve via the product of the Gromov-Witten theories of a point.
This is done by employing mirror symmetry and certain results in FJRW theory.
In particular, we present the particular Givental's action giving the CY/LG
correspondence between the Gromov-Witten theory of the orbifold curve
$\mathcal{E} / \mathbb{Z}_4$ and FJRW theory of the pair defined by the
polynomial $x^4+y^4+z^2$ and the maximal group of diagonal symmetries. The
methods we have developed can easily be applied to other finite quotients of an
elliptic curve. Using Givental's action we also recover this FJRW theory via
the product of the Gromov-Witten theories of a point. Combined with the CY/LG
action we get a result in "pure" Gromov-Witten theory with the help of modern
mirror symmetry conjectures.


title:
Explicit contraction rates for a class of degenerate and
  infinite-dimensional diffusions

abstract:
  Given a separable and real Hilbert space $\mathbb{H}$ and a trace-class,
symmetric and non-negative operator
$\mathcal{G}:\mathbb{H}\rightarrow\mathbb{H}$, we examine the equation
\begin{align*}
  dX_t = -X_t\, dt + b(X_t) \, dt + \sqrt{2} \, dW_t, \qquad
X_0=x\in\mathbb{H},
  \end{align*} where $(W_t)$ is a $\mathcal{G}$-Wiener process on $\mathbb{H}$
and $b:\mathbb{H}\rightarrow\mathbb{H}$ is Lipschitz. We assume there is a
splitting of $\mathbb{H}$ into a finite-dimensional space $\mathbb{H}^l$ and
its orthogonal complement $\mathbb{H}^h$ such that $\mathcal{G}$ is strictly
positive definite on $\mathbb{H}^l$ and the non-linearity $b$ admits a
contraction property on $\mathbb{H}^h$. Assuming a geometric drift condition,
we derive a Kantorovich ($L^1$ Wasserstein) contraction with an explicit rate
for the corresponding Markov kernels. The estimates for the rate are based on
the eigenvalues of $\mathcal{G}$ on the space $\mathbb{H}^l$, a Lipschitz bound
on $b$ and a geometric drift condition. The results are derived using coupling
methods.


title:
Periodic solutions of singular first-order Hamiltonian systems of
  N-vortex type

abstract:
  We are concerned with the dynamics of $N$ point vortices
$z_1,\dots,z_N\in\Omega\subset\mathbb{R}^2$ in a planar domain. This is
described by a Hamiltonian system \[ \Gamma_k\dot{z}_k(t)=J\nabla_{z_k}
H\big(z(t)\big),\quad k=1,\dots,N, \] where
$\Gamma_1,\dots,\Gamma_N\in\mathbb{R}\setminus\{0\}$ are the vorticities,
$J\in\mathbb{R}^{2\times2}$ is the standard symplectic $2\times2$ matrix, and
the Hamiltonian $H$ is of $N$-vortex type: \[ H(z_1,\dots,z_N)
  = -\frac1{2\pi}\sum_{j\ne k}^N \Gamma_j\Gamma_k\log|z_j-z_k| -
\sum_{j,k=1}^N\Gamma_j\Gamma_kg(z_j,z_k). \] Here
$g:\Omega\times\Omega\to\mathbb{R}$ is an arbitrary symmetric function of class
$C^2$, e.g.\ the regular part of a hydrodynamic Green function. Given a
nondegenerate critical point $a_0\in\Omega$ of $h(z)=g(z,z)$ and a
nondegenerate relative equilibrium $Z(t)\in\mathbb{R}^{2N}$ of the Hamiltonian
system in the plane with $g=0$, we prove the existence of a smooth path of
periodic solutions
$z^{(r)}(t)=\big(z^{(r)}_1(t),\dots,z^{(r)}_N(t)\big)\in\Omega^N$, $0<r<r_0$,
with $z^{(r)}_k(t)\to a_0$ as $r\to0$. In the limit $r\to0$, and after a
suitable rescaling, the solutions look like $Z(t)$.


title: Constructing Data Graphs for Keyword Search

abstract:
  A data graph is a convenient paradigm for supporting keyword search that
takes into account available semantic structure and not just textual relevance.
However, the problem of constructing data graphs that facilitate both
efficiency and effectiveness of the underlying system has hardly been
addressed. A conceptual model for this task is proposed. Principles for
constructing good data graphs are explained. Transformations for generating
data graphs from RDB and XML are developed. The results obtained from these
transformations are analyzed. It is shown that XML is a better starting point
for getting a good data graph.


title:
DeepCut: Object Segmentation from Bounding Box Annotations using
  Convolutional Neural Networks

abstract:
  In this paper, we propose DeepCut, a method to obtain pixelwise object
segmentations given an image dataset labelled with bounding box annotations. It
extends the approach of the well-known GrabCut method to include machine
learning by training a neural network classifier from bounding box annotations.
We formulate the problem as an energy minimisation problem over a
densely-connected conditional random field and iteratively update the training
targets to obtain pixelwise object segmentations. Additionally, we propose
variants of the DeepCut method and compare those to a naive approach to CNN
training under weak supervision. We test its applicability to solve brain and
lung segmentation problems on a challenging fetal magnetic resonance dataset
and obtain encouraging results in terms of accuracy.


title: Some remarks on dp-minimal groups

abstract:
  We prove that $\ omega $-categorical dp-minimal groups are
nilpotent-by-finite. We also show that in dp-minimal definably amenable groups,
f-generic global types are strongly f-generic.


title: Fourier multipliers and group von Neumann algebras

abstract:
  In this paper we establish the $L^p$-$L^q$ boundedness of Fourier multipliers
on locally compact separable unimodular groups for the range of indices
$1<p\leq 2 \leq q<\infty$. Our approach is based on the operator algebras
techniques. The result depends on a version of the Hausdorff-Young-Paley
inequality that we establish on general locally compact separable unimodular
groups. In particular, the obtained result implies the corresponding
H\"ormander's Fourier multiplier theorem on $\mathbb{R}^{n}$ and the
corresponding known results for Fourier multipliers on compact Lie groups.


title: Variational Neural Machine Translation

abstract:
  Models of neural machine translation are often from a discriminative family
of encoderdecoders that learn a conditional distribution of a target sentence
given a source sentence. In this paper, we propose a variational model to learn
this conditional distribution for neural machine translation: a variational
encoderdecoder model that can be trained end-to-end. Different from the vanilla
encoder-decoder model that generates target translations from hidden
representations of source sentences alone, the variational model introduces a
continuous latent variable to explicitly model underlying semantics of source
sentences and to guide the generation of target translations. In order to
perform efficient posterior inference and large-scale training, we build a
neural posterior approximator conditioned on both the source and the target
sides, and equip it with a reparameterization technique to estimate the
variational lower bound. Experiments on both Chinese-English and English-
German translation tasks show that the proposed variational neural machine
translation achieves significant improvements over the vanilla neural machine
translation baselines.


title: Simultaneous Sparse Dictionary Learning and Pruning

abstract:
  Dictionary learning is a cutting-edge area in imaging processing, that has
recently led to state-of-the-art results in many signal processing tasks. The
idea is to conduct a linear decomposition of a signal using a few atoms of a
learned and usually over-completed dictionary instead of a pre-defined basis.
Determining a proper size of the to-be-learned dictionary is crucial for both
precision and efficiency of the process, while most of the existing dictionary
learning algorithms choose the size quite arbitrarily. In this paper, a novel
regularization method called the Grouped Smoothly Clipped Absolute Deviation
(GSCAD) is employed for learning the dictionary. The proposed method can
simultaneously learn a sparse dictionary and select the appropriate dictionary
size. Efficient algorithm is designed based on the alternative direction method
of multipliers (ADMM) which decomposes the joint non-convex problem with the
non-convex penalty into two convex optimization problems. Several examples are
presented for image denoising and the experimental results are compared with
other state-of-the-art approaches.


title: Straight rod with different order of thickness

abstract:
  In this paper, we consider rods whose thickness vary linearly between $\eps$
and $\eps^2$. Our aim is to study the asymptotic behavior of these rods in the
framework of the linear elasticity. We use a decomposition method of the
displacement fields of the form $u=U\_e + \bar{u}$, where $U\_e$ stands for the
translation-rotations of the cross-sections and $\bar{u}$ is related to their
deformations. We establish a priori estimates. Passing to the limit in a fixed
domain gives the problems satisfied by the bending, the stretching and the
torsion limit fields which are ordinary differential equations depending on
weights.


title: Entanglement entropy and algebraic holography

abstract:
  In 2006, Ryu and Takayanagi (RT) pointed out that (with a suitable cutoff)
the entanglement entropy between two complementary regions of an equal-time
surface of a d+1-dimensional conformal field theory on the conformal boundary
of AdS_{d+2} is, when the AdS radius is appropriately related to the parameters
of the CFT, equal to 1/4G times the area of the d-dimensional minimal surface
in the AdS bulk which has the junction of those complementary regions as its
boundary, where G is the bulk Newton constant. We point out here that the
RT-equality implies that, in the quantum theory on the bulk AdS background
which is related to the boundary CFT according to Rehren's 1999 algebraic
holography theorem, the entanglement entropy between two complementary bulk
Rehren wedges is equal to 1/4G times the (suitably cut off) area of their
shared ridge. (This follows because of the geometrical fact that, for
complementary ball-shaped regions, the RT minimal surface is precisely the
shared ridge of the complementary bulk Rehren wedges which correspond, under
Rehren's bulk-wedge to boundary double-cone bijection, to the complementary
boundary double-cones whose bases are the RT complementary balls.) This is
consistent with the Bianchi-Meyers conjecture -- that, in a theory of quantum
gravity, the entanglement entropy, S, between the degrees of freedom of a given
region with those of its complement is S = A/4G (+ lower order terms) -- but
only if the phrase 'degrees of freedom' is replaced by 'matter degrees of
freedom'. It also supports related previous arguments of the author --
consistent with the author's 'matter-gravity entanglement hypothesis' -- that
the AdS/CFT correspondence is actually only a bijection between just the matter
(i.e. non-gravity) sector operators of the bulk and the boundary CFT operators.


title: Scaling limits of Markov-Branching trees and applications

abstract:
  The goal of these lectures is to survey some of the recent progress on the
description of large-scale structure of random trees. We use the framework of
Markov-Branching sequences of trees and discuss several applications.


title:
BattRAE: Bidimensional Attention-Based Recursive Autoencoders for
  Learning Bilingual Phrase Embeddings

abstract:
  In this paper, we propose a bidimensional attention based recursive
autoencoder (BattRAE) to integrate clues and sourcetarget interactions at
multiple levels of granularity into bilingual phrase representations. We employ
recursive autoencoders to generate tree structures of phrases with embeddings
at different levels of granularity (e.g., words, sub-phrases and phrases). Over
these embeddings on the source and target side, we introduce a bidimensional
attention network to learn their interactions encoded in a bidimensional
attention matrix, from which we extract two soft attention weight distributions
simultaneously. These weight distributions enable BattRAE to generate
compositive phrase representations via convolution. Based on the learned phrase
representations, we further use a bilinear neural model, trained via a
max-margin method, to measure bilingual semantic similarity. To evaluate the
effectiveness of BattRAE, we incorporate this semantic similarity as an
additional feature into a state-of-the-art SMT system. Extensive experiments on
NIST Chinese-English test sets show that our model achieves a substantial
improvement of up to 1.63 BLEU points on average over the baseline.


title:
Dark Current Reduction of P3HT-Based Organic Photodiode Using a
  Ytterbium Fluoride Buffer Layer in Electron Transport

abstract:
  Photodiodes are widely used to convert lights into electrical signals. The
conventional silicon (Si) based photodiodes boast high photoelectric conversion
efficiency and detectivity. However, in general, inorganic-based photodiodes
have low visible wavelength sensitivity due to their infrared wavelength
absorption. Recently, electrical conducting polymer-based photodiodes have
received significant attention due to their flexibility, low cost of production
and high sensitivity of visible wavelength ranges. In the present work, we
fabricated an organic photodiode (OPD) consisting of ITO/ NiOx/ P3HT:PC60BM/
YbF3/ Al. In the OPD, a yitterbium fluoride (YbF3) buffer layer was used as the
electron transport layer. The OPD was analyzed for its optical-electrical
measurements, including J-V characteristics, detectivity and dynamic
characteristics. We have investigated the physical effects of the YbF3 buffer
layer on the performance of OPD such as its carrier extraction, leakage current
and ohmic characteristics.


title:
Quantifying the Effect on the Load Shifting Potential of Buildings due
  to Ancillary Service Provision

abstract:
  This paper analyzes the pessimistic effect on the inherent load shifting
potential (LSP) of buildings due to the participation in the reserve market. A
generic model-based optimization approach is deployed, which uses a validated
dynamic model along with its experienced external and internal disturbances, to
quantify the LSP in the presence of various price signals. The theoretical
maximum LSP is obtained using a base energy price without the provision of
ancillary services (AS). The deviation from the base case LSP is observed after
including the time varying energy and the reserve price from the spot market.
Factors affecting the LSP are found to be as: (1) physics of the model, (2) the
nature of price signal and (3) the competency of the reserve price with respect
to the energy price. Due to its simple formulation, low computation
requirements, and modular nature, the method proposed in this paper can easily
be deployed by retailers and system operators for the assessment of monetary
incentives as well as qualified load type for various demand response (DR)
services in liberalized markets.


title: Mirror Symmetry for Plane Cubics Revisited

abstract:
  In this expository note we discuss some arithmetic aspects of the mirror
symmetry for plane cubic curves. We also explain how the Picard-Fuchs equation
can be used to reveal part of these arithmetic properties. The application of
Picard-Fuchs equations in studying the genus zero Gromov-Witten invariants of
more general Calabi-Yau varieties and the Weil-Petersson geometry on their
moduli spaces will also be discussed.


title: Knot concordance and homology sphere groups

abstract:
  We study two homomorphisms to the rational homology sphere group. If $\psi$
denotes the inclusion homomorphism from the integral homology sphere group,
then using work of Lisca we show that the image of $\psi$ intersects trivially
with the subgroup of the rational homology sphere group generated by lens
spaces. As corollaries this gives a new proof that the cokernel of $\psi$ is
infinitely generated, and implies that a connected sum $K$ of 2-bridge knots is
concordant to a knot with determinant 1 if and only if $K$ is smoothly slice.
Furthermore, if $\beta$ denotes the homomorphism from the knot concordance
group defined by taking double branched covers of knots, we prove that the
kernel of $\beta$ contains a $\mathbb{Z}^{\infty}$ summand by analyzing the
Tristram-Levine signatures of a family of knots whose double branched covers
all bound rational homology balls.


title: Cubulating mapping tori of polynomial growth free group automorphisms

abstract:
  Let $\Phi:F\rightarrow F$ be a polynomially-growing automorphism of a
finite-rank free group $F$. Then $G=F\rtimes_{_\Phi}\mathbb Z$ acts freely on a
CAT(0) cube complex.


title:
Second Order $L^\infty$ Variational Problems and the
  $\infty$-Polylaplacian

abstract:
  In this paper we initiate the study of $2$nd order variational problems in
$L^\infty$, seeking to minimise the $L^\infty$ norm of a function of the
hessian. We also derive and study the respective PDE arising as the analogue of
the Euler-Lagrange equation. Given $\mathrm{H}\in C^1(\mathbb{R}^{n\times
n}_s)$, for the functional \[ \label{1} \mathrm{E}_\infty(u,\mathcal{O})\, =\,
\big\| \mathrm{H}\big(\mathrm{D}^2 u\big) \big\|_{L^\infty(\mathcal{O})}, \ \ \
u\in W^{2,\infty}(\Omega),\ \mathcal{O}\subseteq \Omega, \tag{1} \] the
associated equation is the fully nonlinear 3rd order PDE \[ \label{2}
\mathrm{A}^2_\infty u\,
:=\,\big(\mathrm{H}_X\big(\mathrm{D}^2u\big)\big)^{\otimes
3}:\big(\mathrm{D}^3u\big)^{\otimes 2}\, =\,0. \tag{2} \] Special cases arise
when $\mathrm{H}$ is the Euclidean length of either the full hessian or of the
Laplacian, leading to the $\infty$-Polylaplacian and the $\infty$-Bilaplacian
respectively. We establish several results for \eqref{1} and \eqref{2},
including existence of minimisers, of absolute minimisers and of "critical
point" generalised solutions, proving also variational characterisations and
uniqueness. We also construct explicit generalised solutions and perform
numerical experiments.


title: On Helly number for crystals and cut-and-project sets

abstract:
  We prove existence of finite Helly numbers for crystals and for
cut-and-project sets with convex windows; also we prove exact bound of $k+6$
for the Helly number of a crystal consisting of $k$ copies of a single lattice.
We show that there are sets of finite local complexity that do not have finite
Helly numbers.


title: The injection of ten electron/$^{3}$He-rich SEP events

abstract:
  We have derived the particle injections at the Sun for ten good
electron/$^{3}$He-rich solar energetic particle (SEP) events, using a 1.2 AU
particle path length (suggested by analysis of the velocity dispersion). The
inferred solar injections of high-energy ($\sim$10 to 300 keV) electrons and of
$\sim$MeV/nucleon ions (carbon and heavier) start with a delay of 17$\pm$3
minutes and 75$\pm$14 minutes, respectively, after the injection of low-energy
($\sim$0.4 to 9 keV) electrons. The injection duration (averaged over energy)
ranges from $\sim$200 to 550 minutes for ions, from $\sim$90 to 160 minutes for
low-energy electrons, and from $\sim$10 to 30 minutes for high-energy
electrons. Most of the selected events have no reported H$\alpha$ flares or
GOES SXR bursts, but all have type III radio bursts that typically start after
the onset of a low-energy electron injection. All nine events with SOHO/LASCO
coverage have a relatively fast ($>$570km/s), mostly narrow
($\lesssim$30$^{\circ}$), west-limb coronal mass ejection (CME) that launches
near the start of the low-energy electron injection, and reaches an average
altitude of $\sim$1.0 and 4.7 $R_{S}$, respectively, at the start of the
high-energy electron injection and of the ion injection. The electron energy
spectra show a continuous power law extending across the transition from low to
high energies, suggesting that the low-energy electron injection may provide
seed electrons for the delayed high-energy electron acceleration. The delayed
ion injections and high ionization states may suggest an ion acceleration along
the lower altitude flanks, rather than at the nose of the CMEs.


title:
A dispersive wave pattern on Jupiter's fastest retrograde jet at
  $20^\circ$S

abstract:
  A compact wave pattern has been identified on Jupiter's fastest retrograding
jet at 20S (the SEBs) on the southern edge of the South Equatorial Belt. The
wave has been identified in both reflected sunlight from amateur observations
between 2010 and 2015, thermal infrared imaging from the Very Large Telescope
and near infrared imaging from the Infrared Telescope Facility. The wave
pattern is present when the SEB is relatively quiescent and lacking large-scale
disturbances, and is particularly notable when the belt has undergone a fade
(whitening). It is generally not present when the SEB exhibits its usual
large-scale convective activity ('rifts'). Tracking of the wave pattern and
associated white ovals on its southern edge over several epochs have permitted
a measure of the dispersion relationship, showing a strong correlation between
the phase speed (-43.2 to -21.2 m/s) and the longitudinal wavelength, which
varied from 4.4-10.0 deg. longitude over the course of the observations.
Infrared imaging sensing low pressures in the upper troposphere suggest that
the wave is confined to near the cloud tops. The wave is moving westward at a
phase speed slower (i.e., less negative) than the peak retrograde wind speed
(-62 m/s), and is therefore moving east with respect to the SEBs jet peak.
Unlike the retrograde NEBn jet near 17N, which is a location of strong vertical
wind shear that sometimes hosts Rossby wave activity, the SEBs jet remains
retrograde throughout the upper troposphere, suggesting the SEBs pattern cannot
be interpreted as a classical Rossby wave. Cassini-derived windspeeds and
temperatures reveal that the vorticity gradient is dominated by the baroclinic
term and becomes negative (changes sign) in a region near the cloud-top level
(400-700 mbar) associated with the SEBs, suggesting a baroclinic origin for
this meandering wave pattern. [Abr]


title: Risk Arbitrage and Hedging to Acceptability under Transaction Costs

abstract:
  The classical discrete time model of proportional transaction costs relies on
the assumption that a feasible portfolio process has solvent increments at each
step. We extend this setting in two directions, allowing for convex transaction
costs and assuming that increments of the portfolio process belong to the sum
of a solvency set and a family of multivariate acceptable positions, e.g. with
respect to a dynamic risk measure. We describe the sets of superhedging prices,
formulate several no (risk) arbitrage conditions and explore connections
between them. In the special case when multivariate positions are converted
into a single fixed asset, our framework turns into the no good deals setting.
However, in general, the possibilities of assessing the risk with respect to
any asset or a basket of the assets lead to a decrease of superhedging prices
and the no arbitrage conditions become stronger. The mathematical technique
relies on results for unbounded and possibly non-closed random sets in
Euclidean space.


title:
Radii and binding energies in oxygen isotopes: a puzzle for nuclear
  forces

abstract:
  We present a systematic study of both nuclear radii and binding energies in
(even) oxygen isotopes from the valley of stability to the neutron drip line.
Both charge and matter radii are compared to state-of-the-art {\it ab initio}
calculations along with binding energy systematics. Experimental matter radii
are obtained through a complete evaluation of the available elastic proton
scattering data of oxygen isotopes. We show that, in spite of a good
reproduction of binding energies, {\it ab initio} calculations with
conventional nuclear interactions derived within chiral effective field theory
fail to provide a realistic description of charge and matter radii. A novel
version of two- and three-nucleon forces leads to considerable improvement of
the simultaneous description of the three observables for stable isotopes, but
shows deficiencies for the most neutron-rich systems. Thus, crucial challenges
related to the development of nuclear interactions remain.


title: Enhanced detection of terrestrial gamma-ray flashes by AGILE

abstract:
  At the end of March 2015 the onboard software configuration of the AGILE
satellite was modified in order to disable the veto signal of the
anticoincidence shield for the minicalorimeter instrument. The motivation for
such a change was the understanding that the dead time induced by the
anticoincidence prevented the detection of a large fraction of Terrestrial
Gamma-Ray Flashes (TGFs). The configuration change was highly successful
resulting in an increase of one order of magnitude in TGF detection rate. As
expected, the largest fraction of the new events has short duration ($< 100
\mathrm {\mu s}$), and part of them has simultaneous association with lightning
sferics detected by the World Wide Lightning Location Network (WWLLN). The new
configuration provides the largest TGF detection rate surface density
(TGFs/$\mathrm{km^2}$/year) to date, opening prospects for improved correlation
studies with lightning and atmospheric parameters on short spatial and temporal
scales along the equatorial region.


title:
Single electrons from heavy-flavor mesons in relativistic heavy-ion
  collisions

abstract:
  We study the single electron spectra from $D-$ and $B-$meson semileptonic
decays in Au+Au collisions at $\sqrt{s_{\rm NN}}=$200, 62.4, and 19.2 GeV by
employing the parton-hadron-string dynamics (PHSD) transport approach that has
been shown to reasonably describe the charm dynamics at RHIC and LHC energies
on a microscopic level. In this approach the initial heavy quarks are produced
by using the PYTHIA which is tuned to reproduce the FONLL calculations. The
produced heavy quarks interact with off-shell massive partons in QGP with
scattering cross sections which are calculated in the dynamical quasi-particle
model (DQPM). At energy densities close to the critical energy density the
heavy quarks are hadronized into heavy mesons through either coalescence or
fragmentation. After hadronization the heavy mesons interact with the light
hadrons by employing the scattering cross sections from an effective
Lagrangian. The final heavy mesons then produce single electrons through
semileptonic decay. We find that the PHSD approach well describes the nuclear
modification factor $R_{\rm AA}$ and elliptic flow $v_2$ of single electrons in
d+Au and Au+Au collisions at $\sqrt{s_{\rm NN}}=$ 200 GeV and the elliptic flow
in Au+Au reactions at $\sqrt{s_{\rm NN}}=$ 62.4 GeV from the PHENIX
collaboration, however, the large $R_{\rm AA}$ at $\sqrt{s_{\rm NN}}=$ 62.4 GeV
is not described at all. Furthermore, we make predictions for the $R_{\rm AA}$
of $D-$mesons and of single electrons at the lower energy of $\sqrt{s_{\rm
NN}}=$ 19.2 GeV. Additionally, the medium modification of the azimuthal angle
$\phi$ between a heavy quark and a heavy antiquark is studied. We find that the
transverse flow enhances the azimuthal angular distributions close to $\phi=$ 0
because the heavy flavors strongly interact with nuclear medium in relativistic
heavy-ion collisions and almost flow with the bulk matter.


title:
A Tighter Real-Time Communication Analysis for Wormhole-Switched
  Priority-Preemptive NoCs

abstract:
  Simulations and runtime measurements are some of the methods which can be
used to evaluate whether a given NoC-based platform can accommodate application
workload and fulfil its timing requirements. Yet, these techniques are often
time-consuming, and hence can evaluate only a limited set of scenarios.
Therefore, these approaches are not suitable for safety-critical and hard
real-time systems, where one of the fundamental requirements is to provide
strong guarantees that all timing requirements will always be met, even in the
worst-case conditions. For such systems the analytic-based real-time analysis
is the only viable approach.
  In this paper the focus is on the real-time communication analysis for
wormhole-switched priority-preemptive NoCs. First, we elaborate on the existing
analysis and identify one source of pessimism. Then, we propose an extension to
the analysis, which efficiently overcomes this limitation, and allows for a
less pessimistic analysis. Finally, through a comprehensive experimental
evaluation, we compare the newly proposed approach against the existing one,
and also observe how the trends change with different traffic parameters.


title:
Methods for analyzing surface texture effects of volcanoes with Plinian
  and subplinian eruptions types: Cases of study Lascar (23 S) and Chaiten (42
  S), Chile

abstract:
  This paper presents a new methodology that provides the analysis of surface
texture changes in areas adjacent to the volcano and its impact product of
volcanic activity. To do this, algorithms from digital image processing such as
the co-occurrence matrix and the wavelet transform are used. These methods are
working on images taken by the Landsat satellite platform sensor 5 TM and
Landsat 7 ETM + sensor, and implemented with the purpose of evaluating
superficial changes that can warn of surface movements of the volcano. The
results were evaluated by similarity metrics for grayscale images, and
validated in two different scenarios that have the same type of eruption, but
differ, essentially, in climate and vegetation. Finally, the proposed algorithm
is presented, setting the parameters and constraints for implementation and
use.


title:
Uniform in time lower bound for solutions to a quantum Boltzmann
  equation of bosons

abstract:
  We consider the quantum Boltzmann equation, which describes the growth of the
condensate, or in other words, models the interaction between excited atoms and
a condensate. In this work, the full form of Bogoliubov dispersion law is
considered, which leads to a detailed study of surface integrals inside the
collision operator on energy manifolds. We prove that positive radial solutions
of the quantum Boltzmann equation are bounded from below by a Gaussian,
uniformly in time.


title: Query Expansion with Locally-Trained Word Embeddings

abstract:
  Continuous space word embeddings have received a great deal of attention in
the natural language processing and machine learning communities for their
ability to model term similarity and other relationships. We study the use of
term relatedness in the context of query expansion for ad hoc information
retrieval. We demonstrate that word embeddings such as word2vec and GloVe, when
trained globally, underperform corpus and query specific embeddings for
retrieval tasks. These results suggest that other tasks benefiting from global
embeddings may also benefit from local embeddings.


title: Rabinowitz-Floer homology on Brieskorn manifolds

abstract:
  This thesis considers fillable contact structures on odd-dimensional
manifolds. For that purpose, Rabinowitz-Floer homology (RFH) is used which was
introduced by Cieliebak and Frauenfelder in 2009. A major part of the thesis is
devoted to technical problems in the definition of RFH. In particular, it is
shown that the moduli spaces involved are cut out transversally. Moreover, it
is proved that RFH is essentially invariant under subcritical handle
attachment. Finally, RFH is calculated for some Brieskorn manifolds. The
obtained results are then used to show for every manifold, which supports
fillable contact structures, that there exist either infinitely many different
fillable contact structures, or one contact structure with infinitely many
different fillings or for every fillable contact structure holds that RFH is
infinite dimensional in every degree.


title:
Investigation of heavy ions diffusion under the influence of
  current-driven mechanism and compositional waves in plasma

abstract:
  We consider diffusion caused by a combined influence of the Hall effect and
electric currents, and argue that such diffusion forms chemical inhomogeneities
in plasma. The considered mechanism can be responsible for the formation of
element spots in laboratory and astrophysical plasmas. Such current-driven
diffusion can be accompanied by the propagation of a particular type of waves
which have not been considered earlier. In these waves, the impurity number
density oscillare alone and their frequency is determined by the electric
currents and sort of impurity ions. These compositional waves exist if the
magnetic pressure in plasma is much greater than the gas pressure. Such waves
lead to local variations of chemical composition and, hence, can manifest
themselves by variations of the emission in spectral lines.