title: Effective Mean-Field Inference Method for Nonnegative Boltzmann Machines

abstract:
  Nonnegative Boltzmann machines (NNBMs) are recurrent probabilistic neural
network models that can describe multi-modal nonnegative data. NNBMs form
rectified Gaussian distributions that appear in biological neural network
models, positive matrix factorization, nonnegative matrix factorization, and so
on. In this paper, an effective inference method for NNBMs is proposed that
uses the mean-field method, referred to as the Thouless--Anderson--Palmer
equation, and the diagonal consistency method, which was recently proposed.


title: Mean-field quantum dynamics for a mixture of Bose-Einstein condensates

abstract:
  We study the effective time evolution of a large quantum system consisting of
a mixture of different species of identical bosons in interaction. If the
system is initially prepared so as to exhibit condensation in each component,
we prove that condensation persists at later times and we show quantitatively
that the many-body Schr\"{o}dinger dynamics is effectively described by a
system of coupled cubic non-linear Schr\"{o}dinger equations, one for each
component.


title:
Robustness of the Fractal Regime for the Multiple-Scattering Structure
  Factor

abstract:
  In the single-scattering theory of electromagnetic radiation, the {\it
fractal regime} is a definite range in the photon momentum-transfer $q$, which
is characterized by the scaling-law behavior of the structure factor: $S(q)
\propto 1/q^{d_f}$. This allows a straightforward estimation of the fractal
dimension $d_f$ of aggregates in {\it Small-Angle X-ray Scattering} (SAXS)
experiments. However, this behavior is not commonly studied in optical
scattering experiments because of the lack of information on its domain of
validity. In the present work, we propose a definition of the
multiple-scattering structure factor, which naturally generalizes the
single-scattering function $S(q)$. We show that the mean-field theory of
electromagnetic scattering provides an explicit condition to interpret the
significance of multiple scattering. In this paper, we investigate and discuss
electromagnetic scattering by three classes of fractal aggregates. The results
obtained from the TMatrix method show that the fractal scaling range is divided
into two domains: 1) a genuine fractal regime, which is robust; 2) a possible
anomalous scaling regime, $S(q) \propto 1/q^{\delta}$, with exponent $\delta$
independent of $d_f$, and related to the way the scattering mechanism uses the
local morphology of the scatterer. The recognition, and an analysis, of the
latter domain is of importance because it may result in significant reduction
of the fractal regime, and brings into question the proper mechanism in the
build-up of multiple-scattering.


title:
Modelling and measurements of fibrinogen adsorption on positively
  charged microspheres

abstract:
  Adsorption of fibrinogen on positively charged microspheres was theoretically
and experimentally studied. The structure of monolayers and the maximum
coverage were determined by applying the experimental measurements at pH=3.5
and 9.7 for NaCl concentration in the range of $10^{-3}- 0.15$ M. The maximum
coverage of fibrinogen on latex particles was precisely determined by the AFM
method. Unexpectedly, at pH=3.5, where both fibrinogen molecule and the latex
particles were positively charged, the maximum coverage varied between 0.9 mg
m$^{-2}$ and 1.1 mg m$^{-2}$ for $10^{-2}$ and 0.15 M NaCl, respectively. On
the other hand, at pH=9.7, the maximum coverage of fibrinogen was larger,
varying between 1.8 mg m$^{-2}$ and 3.4 mg m$^{-2}$ for $10^{-2}$ and 0.15 M
NaCl, respectively. The experimental results were quantitatively interpreted by
the numerical simulations.


title: A Mathematical Model of Foreign Capital Inflow

abstract:
  The paper models foreign capital inflow from the developed to the developing
countries in a stochastic dynamic programming (SDP) framework. Under some
regularity conditions, the existence of the solutions to the SDP problem is
proved and they are then obtained by numerical technique because of the
non-linearity of the related functions. A number of comparative dynamic
analyses explore the impact of parameters of the model on dynamic paths of
capital inflow, interest rate in the international loan market and the exchange
rate.


title:
Charged-particle distributions in $pp$ interactions at $\sqrt{s}=8$ TeV
  measured with the ATLAS detector

abstract:
  This paper presents measurements of distributions of charged particles which
are produced in proton--proton collisions at a centre-of-mass energy of
$\sqrt{s} = 8$ TeV and recorded by the ATLAS detector at the LHC. A special
dataset recorded in 2012 with a small number of interactions per beam crossing
(below 0.004) and corresponding to an integrated luminosity of $160 \mathrm{\mu
b^{-1}}$ was used. A minimum-bias trigger was utilised to select a data sample
of more than 9 million collision events. The multiplicity, pseudorapidity, and
transverse momentum distributions of charged particles are shown in different
regions of kinematics and charged-particle multiplicity, including measurements
of final states at high multiplicity. The results are corrected for detector
effects and are compared to the predictions of various Monte Carlo event
generator models which simulate the full hadronic final state.


title:
Simulation study of a rectifying bipolar ion channel: Detailed model
  versus reduced model

abstract:
  We study a rectifying mutant of the OmpF porin ion channel using both
all-atom and reduced models. The mutant was created by Miedema et al. [Nano
Lett., 2007, 7, 2886] on the basis of the N-P semiconductor diode, in which an
N-P junction is formed. The mutant contains a pore region with positive amino
acids on the left-hand side and negative amino acids on the right-hand side.
Experiments show that this mutant rectifies. Although we do not know the
structure of this mutant, we can build an all-atom model for it on the basis of
the structure of the wild type channel. Interestingly, molecular dynamics
simulations for this all-atom model do not produce rectification. A reduced
model that contains only the important degrees of freedom (the positive and
negative amino acids and free ions in an implicit solvent), on the other hand,
exhibits rectification. Our calculations for the reduced model (using the
Nernst-Planck equation coupled to Local Equilibrium Monte Carlo simulations)
reveal a rectification mechanism that is different from that seen for
semiconductor diodes. The basic reason is that the ions are different in nature
from electrons and holes (they do not recombine). We provide explanations for
the failure of the all-atom model including the effect of all the other atoms
in the system as a noise that inhibits the response of ions (that would be
necessary for rectification) to the polarizing external field.


title: Proteins in solution: Fractal surfaces in solutions

abstract:
  The concept of the surface of a protein in solution, as well of the interface
between protein and 'bulk solution', is introduced. The experimental technique
of small angle X-ray and neutron scattering is introduced and described
briefly. Molecular dynamics simulation, as an appropriate computational tool
for studying the hydration shell of proteins, is also discussed. The concept of
protein surfaces with fractal dimensions is elaborated. We finish by exposing
an experimental (using small angle X-ray scattering) and a computer simulation
case study, which are meant as demonstrations of the possibilities we have at
hand for investigating the delicate interfaces that connect (and divide)
protein molecules and the neighboring electrolyte solution.


title: Conserved charges, surface degrees of freedom, and black hole entropy

abstract:
  In this thesis, we study the Hamiltonian and covariant phase space
description of gravitational theories. The phase space represents the allowed
field configurations and is accompanied by a closed nondegenerate 2 form- the
symplectic form. We will show that local/gauge symmetries of the action fall
into two different categories in the phase space formulation. Those
corresponding to constraints in the phase space, and those associated with
nontrivial conserved charges. We argue that while the former is related to
redundant gauge degrees of freedom, the latter leads to physically distinct
states of the system, known as surface degrees of freedom and can induce a
lower dimensional dynamics on the system. These ideas are then implemented to
build the phase space of specific gravitational systems: 1) asymptotically AdS3
spacetimes, and 2) near horizon geometries of extremal black holes (NHEG) in
arbitrary dimension. In the AdS3 phase space, we show that Brown-Henneaux
asymptotic symmetries can be extended inside the bulk of spacetime and hence
become symplectic symmetries of the phase space. We will show that in the NHEG
phase space, surface gravitons form a Virasoro algebra in four dimensions, and
a novel generalization of Virasoro in higher dimensions. The central charge of
the algebra is proportional to the entropy of the corresponding extremal black
hole. We study the holographic description of NHEG phase space and show that
the charges can be computed through a Liouville type stress tensor defined over
a lower dimensional torus. We will discuss whether surface gravitons can serve
as the microscopic origin of black hole entropy.


title:
Note on the equivalence of hierarchical variational models and auxiliary
  deep generative models

abstract:
  This note compares two recently published machine learning methods for
constructing flexible, but tractable families of variational hidden-variable
posteriors. The first method, called "hierarchical variational models" enriches
the inference model with an extra variable, while the other, called "auxiliary
deep generative models", enriches the generative model instead. We conclude
that the two methods are mathematically equivalent.


title:
Searching for Gravitational Waves from Compact Binaries with Precessing
  Spins

abstract:
  Current searches for gravitational waves from compact-object binaries with
the LIGO and Virgo observatories employ waveform models with spins aligned (or
anti-aligned) with the orbital angular momentum. Here, we derive a new
statistic to search for compact objects carrying generic (precessing) spins.
Applying this statistic, we construct banks of both aligned- and generic-spin
templates for binary black holes and neutron-star--black-hole binaries, and
compare the effectualness of these banks towards simulated populations of
generic-spin systems. We then use these banks in a pipeline analysis of
Gaussian noise to measure the increase in background incurred by using generic-
instead of aligned-spin banks. Although the generic-spin banks have a factor of
ten to twenty more templates than the aligned-spin banks, we find an overall
improvement in signal recovery at fixed false-alarm rate for systems with
high-mass ratio and highly precessing spins ---up to 60\% for
neutron-star--black-hole mergers. This gain in sensitivity comes at a small
loss of sensitivity ($\lesssim$4\%) for systems that are already well-covered
by aligned-spin templates. Since the observation of even a single binary merger
with misalinged spins could provide unique astrophysical insights into the
formation of these sources, we recommend that the method described here be
developed further to mount a viable search for generic-spin binary mergers in
LIGO/Virgo data.


title:
Influence of anisotropic ion shape, asymmetric valency, and electrolyte
  concentration on structural and thermodynamic properties of an electric
  double layer

abstract:
  Grand canonical Monte Carlo simulation results are reported for an electric
double layer modelled by a planar charged hard wall, anisotropic shape cations,
and spherical anions at different electrolyte concentrations and asymmetric
valencies. The cations consist of two tangentially tethered hard spheres of the
same diameter, $d$. One sphere is charged while the other is neutral. Spherical
anions are charged hard spheres of diameter $d$. The ion valency asymmetry 1:2
and 2:1 is considered, with the ions being immersed in a solvent mimicked by a
continuum dielectric medium at standard temperature. The simulations are
carried out for the following electrolyte concentrations: 0.1, 1.0 and 2.0 M.
Profiles of the electrode-ion, electrode-neutral sphere singlet distributions,
the average orientation of dimers, and the mean electrostatic potential are
calculated for a given electrode surface charge, $\sigma$, while the contact
electrode potential and the differential capacitance are presented for varying
electrode charge. With an increasing electrolyte concentration, the shape of
differential capacitance curve changes from that with a minimum surrounded by
maxima into that of a distorted single maximum. For a 2:1 electrolyte, the
maximum is located at a small negative $\sigma$ value while for 1:2, at a small
positive value.


title: Level-crossing and modal structure in microdroplet resonators

abstract:
  We fabricate a liquid-core liquid-clad microcavity that is coupled to a
standard tapered fiber, and then experimentally map the whispering-gallery
modes of this droplet resonator. The shape of our resonator is similar to a
thin prolate spheroid, which makes space for many high-order transverse modes,
suggesting that some of them will share the same resonance frequency. Indeed,
we experimentally observe that more than half of the droplet's modes have a
sibling having the same frequency (to within linewidth) and therefore
exhibiting a standing interference-pattern.


title:
A hybrid approach based segmentation technique for brain tumor in MRI
  Images

abstract:
  Automatic image segmentation becomes very crucial for tumor detection in
medical image processing.In general, manual and semi automatic segmentation
techniques require more time and knowledge. However these drawbacks had
overcome by automatic segmentation still there needs to develop more
appropriate techniques for medical image segmentation. Therefore, we proposed
hybrid approach based image segmentation using the combined features of region
growing and threshold based segmentation techniques. It is followed by
pre-processing stage to provide an accurate brain tumor extraction by the help
of Magnetic Resonance Imaging (MRI). If the tumor has holes, the region growing
segmentation algorithm cannot reveal but the proposed hybrid segmentation
technique can be achieved and the result as well improved. Hence the result
used to made assessment with the various performance measures as DICE, JACCARD
similarity, accuracy, sensitivity and specificity. These similarity measures
have been extensively used for evaluation with the ground truth of each
processed image and its results are compared and analyzed.


title: Singular limit analysis of a model for earthquake faulting

abstract:
  In this paper we consider the one dimensional spring-block model describing
earthquake faulting. By using geometric singular perturbation theory and the
blow-up method we provide a detailed description of the periodicity of the
earthquake episodes. In particular, the limit cycles arise from a degenerate
Hopf bifurcation whose degeneracy is due to an underlying Hamiltonian structure
that leads to large amplitude oscillations. We use a Poincar\'e
compactification to study the system near infinity. At infinity the critical
manifold loses hyperbolicity with an exponential rate. We use an adaptation of
the blow-up method to recover the hyperbolicity. This enables the
identification of a new attracting manifold that organises the dynamics at
infinity. This in turn leads to the formulation of a conjecture on the
behaviour of the limit cycles as the time-scale separation increases. We
illustrate our findings with numerics and suggest an outline of the proof of
this conjecture.


title: Four-dimensional homogeneous semi-symmetric Lorentzian manifolds

abstract:
  We give a complete description of semi-symmetric algebraic curvature tensors
on a four-dimensional Lorentzian vector space and we use this description to
determine all four-dimensional homogeneous semi-symmetric Lorentzian manifolds.


title:
Analytical study on parameter regions of dynamical instability for
  two-component Bose--Einstein condensates with coaxial quantized vortices

abstract:
  The dynamical instability of weakly interacting two-component Bose--Einstein
condensates with coaxial quantized vortices is analytically investigated in a
two-dimensional isotopic harmonic potential. We examine whether complex
eigenvalues appear on the Bogoliubov--de Gennes equation, implying dynamical
instability. Rather than solving the Bogoliubov--de Gennes equation
numerically, we rely on a perturbative expansion with respect to the coupling
constant which enables a simple, analytic approach. For each pair of winding
numbers and for each magnetic quantum number, the ranges of inter-component
coupling constant where the system is dynamically unstable are exhaustively
obtained. Co-rotating and counter-rotating systems show distinctive behaviors.
The latter is much more complicated than the former with respect to dynamical
instability, particularly because radial excitations contribute to complex
eigenvalues in counter-rotating systems.


title: $K^+$-nucleus potentials from $K^+$-nucleon amplitudes

abstract:
  Optical potentials for $K^+$-nucleus interactions are constructed from
$K^+$-nucleon amplitudes using recently developed algorithm based on $K^+$-N
kinematics in the nuclear medium. With the deep penetration of $K^+$ mesons
into the nucleus at momenta below 800~MeV/c it is possible to test this
approach with greater sensitivity than hitherto done with $K^-$ and pions. The
energy-dependence of experimental reaction and total cross sections on nuclei
is better reproduced with this approach compared to fixed-energy amplitudes.
The inclusion of Pauli correlations in the medium also improves the agreement
between calculation and experiment. The absolute scale of the cross sections is
reproduced very well for $^6$Li but for C, Si and Ca calculated cross sections
are (23$\pm4$)\% smaller than experiment, in agreement with earlier analyses.
Two phenomenological models that produce such missing strength suggest that the
imaginary part of the potential needs about 40\% enhancement.


title:
New developments in exact amplitude-based resummation in precision
  theory vs experiment

abstract:
  We present recent developments in the application of exact amplitude-based
resummation methods in the confrontation between precision theory and recent
experimental results. As a consequence, we argue that these methods open the
way to 1\% total theoretical precision in LHC and FCC physics when realized via
MC event generators.


title:
Proofreading of DNA Polymerase: a new kinetic model with higher-order
  terminal effects

abstract:
  The fidelity of DNA replication by DNA polymerase (DNAP) has long been an
important issue in biology. While numerous experiments have revealed details of
the molecular structure and working mechanism of DNAP which consists of both a
polymerase site and an exonuclease (proofreading) site, there were quite few
theoretical studies on the fidelity issue. The first model which explicitly
considered both sites was proposed in 1970s' and the basic idea was widely
accepted by later models. However, all these models did not systematically and
rigorously investigate the dominant factor on DNAP fidelity, i.e, the
higher-order terminal effects through which the polymerization pathway and the
proofreading pathway coordinate to achieve high fidelity. In this paper, we
propose a new and comprehensive kinetic model of DNAP based on some recent
experimental observations, which includes previous models as special cases. We
present a rigorous and unified treatment of the corresponding steady-state
kinetic equations of any-order terminal effects, and derive analytical
expressions for fidelity in terms of kinetic parameters under bio-relevant
conditions. These expressions offer new insights on how the the higher-order
terminal effects contribute substantially to the fidelity in an order-by-order
way, and also show that the polymerization-and-proofreading mechanism is
dominated only by very few key parameters. We then apply these results to
calculate the fidelity of some real DNAPs, which are in good agreements with
previous intuitive estimates given by experimentalists.


title:
Nonzero-Sum Risk Sensitive Stochastic Games for Continuous Time Markov
  Chains

abstract:
  We study nonzero-sum stochastic games for continuous time Markov chains on a
denumerable state space with risk sensitive discounted and ergodic cost
criteria. For the discounted cost criterion we first show that the
corresponding system of coupled HJB equations has an appropriate solution. Then
under an additional additive structure on the transition rate matrix and payoff
functions, we establish the existence of a Nash equilibrium in Markov
strategies. For the ergodic cost criterion we assume a Lyapunov type stability
assumption and a small cost condition. Under these assumptions we show that the
corresponding system of coupled HJB equations admits a solution which leads to
the existence of Nash equilibrium in stationary strategies.


title:
Optical lattice influenced geometry of quasi-2D binary condensates and
  quasiparticle spectra

abstract:
  We explore the collective excitations of optical lattices filled with
two-species Bose-Einstein condensates (TBECs). We use a set of coupled discrete
nonlinear Schr\"odinger equations to describe the system, and employ
Hartree-Fock-Bogoliubov (HFB) theory with the Popov approximation to analyze
the quasiparticle spectra at zero temperature. The ground state geometry,
evolution of quasiparticle energies, structure of quasiparticle amplitudes, and
dispersion relations are examined in detail. The trends observed are in stark
contrast to the case of TBECs only with a harmonic confining potential. One key
observation is the quasiparticle energies are softened as the system is tuned
towards phase separation, but harden after phase separation and mode
degeneracies are lifted.


title:
Exact completion of path categories and algebraic set theory -- Part I:
  Exact completion of path categories

abstract:
  We introduce the notion of a "category with path objects", as a slight
strengthening of Kenneth Brown's classic notion of a "category of fibrant
objects". We develop the basic properties of such a category and its associated
homotopy category. Subsequently, we show how the exact completion of this
homotopy category can be obtained as the homotopy category associated to a
larger category with path objects, obtained by freely adjoining certain
homotopy quotients. In a second part of this paper, we will present an
application to models of constructive set theory. Although our work is partly
motivated by recent developments in homotopy type theory, this paper is written
purely in the language of homotopy theory and category theory, and we do not
presuppose any familiarity with type theory on the side of the reader.


title: On Self-Reducibility and Reoptimization of Closest Substring Problem

abstract:
  In this paper, we define the reoptimization variant of the closest substring
problem (CSP) under sequence addition. We show that, even with the additional
information we have about the problem instance, the problem of finding a
closest substring is still NP-hard. We investigate the combinatorial property
of optimization problems called self-reducibility. We show that problems that
are polynomial-time reducible to self-reducible problems also exhibits the same
property. We illustrate this in the context of CSP. We used the property to
show that although we cannot improve the approximability of the problem, we can
improve the running time of the existing PTAS for CSP.


title:
Exponential stability of a PI plus reset integrator controller by a
  sampled-data system approach

abstract:
  The paper deals with the stability analysis of time-delay reset control
systems, for which the resetting law is assumed to satisfy a time-dependent
condition. A stability analysis of the closed-loop system is performed based on
an appropriate sampled-data system. New linear matrix inequality (LMI)
conditions are proposed to ensure the exponential stability of the closed-loop
resulting of the connection of a plant with a proportional and integral
controller together with a reset integrator (PI+RI).


title:
A Genetic Algorithm for Chromaticity Correction in Diffraction Limited
  Storage Rings

abstract:
  A multi-objective genetic algorithm is developed for optimizing
nonlinearities in diffraction limited storage rings. This algorithm determines
sextupole and octupole strengths for chromaticity correction that deliver
optimized dynamic aperture and beam lifetime. The algorithm makes use of
dominance constraints to breed desirable properties into the early generations.
The momentum aperture is optimized indirectly by constraining the chromatic
tune footprint and optimizing the off-energy dynamic aperture. The result is an
effective and computationally efficient technique for correcting chromaticity
in a storage ring while maintaining optimal dynamic aperture and beam lifetime.
This framework was developed for the Swiss Light Source (SLS) upgrade project.


title:
The ASTRODEEP Frontier Fields Catalogues: I - Multiwavelength photometry
  of Abell-2744 and MACS-J0416

abstract:
  We present multiwavelength photometric catalogues (HST, Spitzer and Hawk-I K
band) for the first two of the Frontier Fields, Abell2744 and MACSJ0416 (plus
their parallel fields). To detect faint sources even in the central regions of
the clusters, we develop a robust and repeatable procedure that uses the public
codes Galapagos and Galfit to model and remove most of the light contribution
from both the brightest cluster members as well as the ICL. We perform the
detection on the HST H160 processed image to obtain a pure H-selected sample.
We also add a sample of sources which are undetected in the H160 image but
appear on a stacked infrared image. Photometry in the other HST bands is
obtained using SExtractor, performed again on residual images after the Galfit
procedure for foreground light removal. Photometry on the Hawk-I and IRAC bands
has been obtained using our PSF-matching deconfusion code T-PHOT. A similar
procedure, but without the need for the foreground light removal, is adopted
for the Parallel fields. The procedure allows for the detection and the
photometric measurements of ~2500 sources per field. We deliver and release
complete photometric H-detected catalogues, with the addition of a
complementary sample of infrared-detected sources. All objects have
multiwavelength coverage including B to H HST bands, plus K band from Hawk-I,
and 3.6 - 4.5 {\mu}m from Spitzer. Full and detailed treatment of photometric
errors is included. We perform basic sanity checks on the reliability of our
results. The multiwavelength catalogues are publicly available and are ready to
be used for scientific purposes. Our procedures allows for the detection of
outshined objects near the bright galaxies, which, coupled with the
magnification effect of the clusters, can reveal extremely faint high redshift
sources. Full analysis on photometric redshifts is presented in a companion
Paper II. [abridged]


title:
The ASTRODEEP Frontier Fields Catalogues: II - Photometric redshifts and
  rest-frame properties in Abell-2744 and MACS-J0416

abstract:
  We present the first public release of photometric redshifts, galaxy
rest-frame properties and associated magnification values in the cluster and
parallel pointings of the first two Frontier Fields, Abell-2744 and MACS-J0416.
We exploit a multi-wavelength catalogue ranging from HST to ground-based K and
Spitzer IRAC which is specifically designed to enable detection and measurement
of accurate fluxes in crowded cluster regions. The multi-band information is
used to derive photometric redshifts and physical properties of sources
detected either in the H-band image alone or from a stack of four WFC3 bands.
To minimize systematics median photometric redshifts are assembled from six
different approaches to photo-z estimates. Their reliability is assessed
through a comparison with available spectroscopic samples. State of the art
lensing models are used to derive magnification values on an object-by-object
basis by taking into account sources positions and redshifts. We show that
photometric redshifts reach a remarkable ~3-5% accuracy. After accounting for
magnification the H band number counts are found in agreement at bright
magnitudes with number counts from the CANDELS fields, while extending the
presently available samples to galaxies intrinsically as faint as H160~32-33
thanks to strong gravitational lensing. The Frontier Fields allow to probe the
galaxy stellar mass distribution at 0.5-1.5 dex lower masses, depending on
magnification, with respect to extragalactic wide fields, including sources at
Mstar~ 10^7-10^8 Msun at z>5. Similarly, they allow the detection of objects
with intrinsic SFRs>1dex lower than in the CANDELS fields reaching 0.1-1
Msun/yr at z~6-10. [abridged]


title: Neutrino-atom collisions

abstract:
  Neutrino-atom scattering provides a sensitive tool for probing nonstandard
interactions of massive neutrinos in laboratory measurements. The ionization
channel of this collision process plays an important role in experiments
searching for neutrino magnetic moments. We discuss some theoretical aspects of
atomic ionization by massive neutrinos. We also outline possible manifestations
of neutrino electromagnetic properties in coherent elastic neutrino-nucleus
scattering.


title:
Perturbative Interpretation of Adaptive Thouless-Anderson-Palmer Free
  Energy

abstract:
  In conventional well-known derivation methods for the adaptive
Thouless-Anderson-Palmer (TAP) free energy, special assumptions that are
difficult to mathematically justify except in some mean-field models, must be
made. Here, we present a new adaptive TAP free energy derivation method. Using
this derivation technique, without any special assumptions, the adaptive TAP
free energy can be simply obtained as a high-temperature expansion of the Gibbs
free energy.


title: Discrete knot energies

abstract:
  The present chapter gives an overview on results for discrete knot energies.
These discrete energies are designed to make swift numerical computations and
thus open the field to computational methods. Additionally, they provide an
independent, geometrically pleasing and consistent discrete model that behaves
similarly to the original model. We will focus on M\"obius energy, integral
Menger curvature and thickness.


title: Core-Collapse supernovae and its progenitors

abstract:
  Massive stars unable to sustain gravitational collapse, at the end of nuclear
burning stage, turns out into core-collapse supernovae, leaving behind compact
objects like neutron stars or black holes. The progenitor properties like mass
and metallicity primarily governs the explosion parameters and type of compact
remnant. In this contribution we summarize observational study of three Core
Collapse type IIP SNe 2012aw, 2013ab and 2013ej, which are rigorously observed
from ARIES and other Indian observatories and discuss their progenitor and
explosion properties.


title:
A non-extensive entropy feature and its application to texture
  classification

abstract:
  This paper proposes a new probabilistic non-extensive entropy feature for
texture characterization, based on a Gaussian information measure. The
highlights of the new entropy are that it is bounded by finite limits and that
it is non additive in nature. The non additive property of the proposed entropy
makes it useful for the representation of information content in the
non-extensive systems containing some degree of regularity or correlation. The
effectiveness of the proposed entropy in representing the correlated random
variables is demonstrated by applying it for the texture classification problem
since textures found in nature are random and at the same time contain some
degree of correlation or regularity at some scale. The gray level co-occurrence
probabilities (GLCP) are used for computing the entropy function. The
experimental results indicate high degree of the classification accuracy. The
performance of the new entropy function is found superior to other forms of
entropy such as Shannon, Renyi, Tsallis and Pal and Pal entropies on
comparison. Using the feature based polar interaction maps (FBIM) the proposed
entropy is shown to be the best measure among the entropies compared for
representing the correlated textures.


title:
The Mathematics of Xenology: Di-cographs, Symbolic Ultrametrics,
  2-structures and Tree-representable Systems of Binary Relations

abstract:
  The concepts of orthology, paralogy, and xenology play a key role in
molecular evolution. Orthology and paralogy distinguish whether a pair of genes
originated by speciation or duplication. The corresponding binary relations on
a set of genes form complementary cographs. Allowing more than two types of
ancestral event types leads to symmetric symbolic ultrametrics. Horizontal gene
transfer, which leads to xenologous gene pairs, however, is inherent asymmetric
since one offspring copy "jumps" into another genome, while the other continues
to be inherited vertically. We therefore explore here the mathematical
structure of the non-symmetric generalization of symbolic ultrametrics. Our
main results tie non-symmetric ultrametrics together with di-cographs (the
directed generalization of cographs), so-called uniformly non-prime
2-structures, and hierarchical structures on the set of strong modules. This
yields a characterization of relation structures that can be explained in terms
of trees and types of ancestral events. This framework accommodates a
horizontal-transfer relation in terms of an ancestral event and thus, is
slightly different from the the most commonly used definition of xenology.


title: On the link between binomial theorem and discrete convolution

abstract:
  Let $\mathbf{P}^{m}_{b}(x)$ be a $2m+1$-degree integer-valued polynomial in
$b,x\in\mathbb{R}$ \[
  \mathbf{P}^{m}_{b}(x) = \sum_{k=0}^{b-1} \sum_{r=0}^{m} \mathbf{A}_{m,r}
k^r(x-k)^r, \] where $\mathbf{A}_{m,r}$ is a real coefficient. In this
manuscript we establish a relation between Binomial theorem and polynomial
$\mathbf{P}^{m}_{b}(x)$. Furthermore, a relationship between Binomial theorem
and discrete convolution in terms of polynomials is provided.


title: A nonstandard proof for Szpilrajn's theorem

abstract:
  Recall that Szpilrajn (1930) ([4], [5]) states that on a given set, any
partial order can be extended to a total order on the same set. In this work we
give, in the context of the IST theory ([2],[3],[6]), a more constructive proof
for this theorem. In addition, we benefit of the tools used to give some other
results.


title: What can simulated molecular clouds tell us about real molecular clouds?

abstract:
  We study the properties of giant molecular clouds (GMCs) from a smoothed
particle hydrodynamics simulation of a portion of a spiral galaxy, modelled at
high resolution, with robust representations of the physics of the interstellar
medium. We examine the global molecular gas content of clouds, and investigate
the effect of using CO or H2 densities to define the GMCs. We find that CO can
reliably trace the high-density H2 gas, but misses less dense H2 clouds. We
also investigate the effect of using 3D CO densities versus CO emission with an
observer's perspective, and find that CO-emission clouds trace well the peaks
of the actual GMCs in 3D, but can miss the lower density molecular gas between
density peaks which is often CO-dark. Thus, the CO emission typically traces
smaller clouds within larger GMC complexes. We also investigate the effect of
the galactic environment (in particular the presence of spiral arms), on the
distribution of GMC properties, and we find that the mean properties are
similar between arm and inter-arm clouds, but the tails of some distributions
are indicative of intrinsic differences in the environment. We find highly
filamentary clouds (similar to the giant molecular filaments of our Galaxy)
exclusively in the inter-arm region, formed by galactic shear. We also find
that the most massive GMC complexes are located in the arm, and that as a
consequence of more frequent cloud interactions/mergers in the arm, arm clouds
are more sub-structured and have higher velocity dispersions than inter-arm
clouds.


title:
The best constant in the Khintchine inequality of the Orlicz space
  $L_{\psi_2}$ for equidistributed random variables on spheres

abstract:
  We compute the best constant in the Khintchine inequality for equidistributed
random variables on the $N$-sphere in the Orlicz space $L_{\psi_2}$.


title:
Anticipatory Radio Resource Management for Mobile Video Streaming with
  Linear Programming

abstract:
  In anticipatory networking, channel prediction is used to improve
communication performance. This paper describes a new approach for allocating
resources to video streaming traffic while accounting for quality of service.
The proposed method is based on integrating a model of the user's local
play-out buffer into the radio access network. The linearity of this model
allows to formulate a Linear Programming problem that optimizes the trade-off
between the allocated resources and the stalling time of the media stream. Our
simulation results demonstrate the full power of anticipatory optimization in a
simple, yet representative, scenario. Compared to instantaneous adaptation, our
anticipatory solution shows impressive gains in spectral efficiency and
stalling duration at feasible computation time while being robust against
prediction errors.


title:
On the parity of the multiplicative order of certain products of
  integers related to Gauss factorials

abstract:
  In this note, we prove that under some conditions, certain products of
integers related to Gauss factorials are always quadratic residues.


title: Sparse spanning $k$-connected subgraphs in tournaments

abstract:
  In 2009, Bang-Jensen asked whether there exists a function $g(k)$ such that
every strongly $k$-connected $n$-vertex tournament contains a strongly
$k$-connected spanning subgraph with at most $kn + g(k)$ arcs. In this paper,
we answer the question by showing that every strongly $k$-connected $n$-vertex
tournament contains a strongly $k$-connected spanning subgraph with at most $kn
+ 750k^2\log(k+1)$ arcs.


title:
Self-organisation in protoplanetary disks: global, non-stratified
  Hall-MHD simulations

abstract:
  Recent observations revealed organised structures in protoplanetary disks,
such as axisymmetric rings or horseshoe concen- trations evocative of
large-scale vortices. These structures are often interpreted as the result of
planet-disc interactions. However, these disks are also known to be unstable to
the magneto-rotational instability (MRI) which is believed to be one of the
dominant angular momentum transport mechanism in these objects. It is therefore
natural to ask if the MRI itself could produce these structures without
invoking planets. The nonlinear evolution of the MRI is strongly affected by
the low ionisation fraction in protoplanetary disks. The Hall effect in
particular, which is dominant in dense and weakly ionised parts of these
objects, has been shown to spontaneously drive self- organising flows in
shearing box simulations. Here, we investigate the behaviour of global
MRI-unstable disc models dominated by the Hall effect and characterise their
dynamics. We perform 3D unstratified Hall-MHD simulations of keplerian disks
for a broad range of Hall, ohmic and ambipolar Elsasser numbers. We confirm the
transition from a turbulent to an organised state as the intensity of the Hall
effect is increased. We observe the formation of zonal flows, their number
depending on the available magnetic flux and on the intensity of the Hall
effect. For intermediate Hall intensity, the flow self-organises into
long-lived magnetised vortices. Neither the addition of a toroidal field nor
ohmic or ambipolar diffusion drastically change this picture in the range of
parameters we have explored. The ability of these structures to trap dust
particles in this configuration is demonstrated. We conclude that Hall-MRI
driven organisation is a plausible scenario which could explain some of the
structures found in recent observations.


title:
Fair Scheduling for Data Collection in Mobile Sensor Networks with
  Energy Harvesting

abstract:
  We consider the problem of data collection from a continental-scale network
of energy harvesting sensors, applied to tracking mobile assets in rural
environments. Our application constraints favour a highly asymmetric solution,
with heavily duty-cycled sensor nodes communicating with powered base stations.
We study a novel scheduling optimisation problem for energy harvesting mobile
sensor network, that maximises the amount of collected data under the
constraints of radio link quality and energy harvesting efficiency, while
ensuring a fair data reception. We show that the problem is NP-complete and
propose a heuristic algorithm to approximate the optimal scheduling solution in
polynomial time. Moreover, our algorithm is flexible in handling progressive
energy harvesting events, such as with solar panels, or opportunistic and
bursty events, such as with Wireless Power Transfer. We use empirical link
quality data, solar energy, and WPT efficiency to evaluate the proposed
algorithm in extensive simulations and compare its performance to
state-of-the-art. We show that our algorithm achieves high data reception
rates, under different fairness and node lifetime constraints.


abstract:
  Tunable photonic elements at the surface of an optical fiber with
piezoelectric core are proposed and analyzed theoretically. These elements are
based on whispering gallery modes whose propagation along the fiber is fully
controlled by nanoscale variation of the effective fiber radius, which can be
tuned by means of a piezoelectric actuator embedded into the core. The
developed theory allows one to express the introduced effective radius
variation through the shape of the actuator and the voltage applied to it. In
particular, the design of a miniature tunable optical delay line and a
miniature tunable dispersion compensator is presented. The potential
application of the suggested model to the design of a miniature optical buffer
is discussed.


title: An Introduction to Mechanized Reasoning

abstract:
  Mechanized reasoning uses computers to verify proofs and to help discover new
theorems. Computer scientists have applied mechanized reasoning to economic
problems but -- to date -- this work has not yet been properly presented in
economics journals. We introduce mechanized reasoning to economists in three
ways. First, we introduce mechanized reasoning in general, describing both the
techniques and their successful applications. Second, we explain how mechanized
reasoning has been applied to economic problems, concentrating on the two
domains that have attracted the most attention: social choice theory and
auction theory. Finally, we present a detailed example of mechanized reasoning
in practice by means of a proof of Vickrey's familiar theorem on second-price
auctions.


title:
Evaluation of the performance of two state-transfer Hamiltonians in the
  presence of static disorder

abstract:
  We analyse the performance of two quantum-state-transfer Hamiltonians in the
presence of diagonal and off-diagonal disorder, and in terms of different
measures. The first Hamiltonian pertains to a fully-engineered chain and the
second to a chain with modified boundary couplings. The task is to find which
Hamiltonian is the most robust to given levels of disorder and irrespective of
the input state. In this respect, it is shown that the performance of the two
protocols are approximately equivalent.


title:
A Hybrid Transmission Grid Architecture Enabling Efficient Optimal Power
  Flow

abstract:
  The recent rise of electricity generation based on renewable energy sources
increases the demand for transmission capacity. Capacity expansion via the
upgrade of transmission line capacity, e.g., by conversion to a high-voltage
direct current (HVDC) line, is an attractive option. In this paper, it is shown
that if the upgrade to HVDC is applied systematically to selected transmission
lines across the grid, a hybrid architecture is obtained that enables an
efficient and globally optimal solution of the optimal power flow (OPF)
problem. More precisely, for conventional meshed AC transmission grids the OPF
problem is nonconvex and in general NP-hard, rendering it hard to solve. We
prove that after the upgrade to the proposed hybrid architecture, the same mesh
topology facilitates an exact convex relaxation of the OPF problem, enabling
its globally optimal solution with efficient polynomial time algorithms. This
OPF method is then employed in simulations, which demonstrate that the hybrid
architecture can increase the effective transmission capacity and substantially
reduce the generation costs, even compared to the AC grid with optimal
transmission switching.


title: A Software Package for Chemically Inspired Graph Transformation

abstract:
  Chemical reaction networks can be automatically generated from graph grammar
descriptions, where rewrite rules model reaction patterns. Because a molecule
graph is connected and reactions in general involve multiple molecules, the
rewriting must be performed on multisets of graphs. We present a general
software package for this type of graph rewriting system, which can be used for
modelling chemical systems. The package contains a C++ library with algorithms
for working with transformation rules in the Double Pushout formalism, e.g.,
composition of rules and a domain specific language for programming graph
language generation. A Python interface makes these features easily accessible.
The package also has extensive procedures for automatically visualising not
only graphs and rewrite rules, but also Double Pushout diagrams and graph
languages in form of directed hypergraphs. The software is available as an open
source package, and interactive examples can be found on the accompanying
webpage.


title:
Resonantly Enhanced Multiphoton Ionization under XUV FEL radiation: A
  case study of the role of harmonics

abstract:
  We provide a detailed quantitative study of the possible role of a small
admixture of harmonics on resonant two-photon ionization. The motivation comes
from the occasional presence of 2nd and 3rd harmonics in FEL radiation. We
obtain the dependence of ionic yields on the intensity of the fundamental, the
percentage of 2nd harmonic and the detuning of the fundamental from resonance.
Having examined the cases of one and two intermediate resonances, we arrive at
results of general validity and global behavior, showing that even a small
amount of harmonic may seem deceptively innocuous.


title:
Translational and rotational dynamics of a large buoyant sphere in
  turbulence

abstract:
  We report experimental measurements of the translational and rotational
dynamics of a large buoyant sphere in isotropic turbulence. We introduce an
efficient method to simultaneously determine the position and (absolute)
orientation of a spherical body from visual observation. The method employs a
minimization algorithm to obtain the orientation from the 2D projection of a
specific pattern drawn onto the surface of the sphere. This has the advantages
that it does not require a database of reference images, is easily scalable
using parallel processing, and enables accurate absolute orientation reference.
Analysis of the sphere's translational dynamics reveals clear differences
between the streamwise and transverse directions. The translational
auto-correlations and PDFs provide evidence for periodicity in the particle's
dynamics even under turbulent conditions. The angular autocorrelations show
weak periodicity. The angular accelerations exhibit wide tails, however without
a directional dependence.


title:
The Exploratory Research of the Effect Communication Model and Effect
  Improving Strategy of Interactive Advertising

abstract:
  Interactive advertising which characterized by interactivity has become the
mainstream of advertising by gradually replacing traditional one-way
advertising during the new media era. This paper has obeyed the research
outline below, literature review, background description, assumption proposed,
and empirical analysis. Therefore, this paper proposed the communication model
of interactive advertising and drawn two related important conclusions,
interactivity has brought positive effect to advertising communication,
different type of consumers tend to use different interactive options in
different ways. Furthermore, this paper also presented three related
optimization strategies to improving the communication of interactive
advertising, namely, 1.changing communication model from one-way to two-way,
2.renovating new communication process and effect-generated path, 3.renovating
new strategy portfolio to improving the communication effect of interactive
advertising.


title: The Block Pseudo-Marginal Sampler

abstract:
  The pseudo-marginal (PM) approach is increasingly used for Bayesian inference
in statistical models, where the likelihood is intractable but can be estimated
unbiasedly. %Examples include random effect models, state-space models and data
subsampling in big-data settings. Deligiannidis et al. (2016) show how the PM
approach can be made much more efficient by correlating the underlying Monte
Carlo (MC) random numbers used to form the estimate of the likelihood at the
current and proposed values of the unknown parameters. Their approach greatly
speeds up the standard PM algorithm, as it requires a much smaller number of
samples or particles to form the optimal likelihood estimate. Our paper
presents an alternative implementation of the correlated PM approach, called
the block PM, which divides the underlying random numbers into blocks so that
the likelihood estimates for the proposed and current values of the parameters
only differ by the random numbers in one block. We show that this
implementation of the correlated PM can be much more efficient for some
specific problems than the implementation in Deligiannidis et al. (2016); for
example when the likelihood is estimated by subsampling or the likelihood is a
product of terms each of which is given by an integral which can be estimated
unbiasedly by randomised quasi-Monte Carlo. Our article provides methodology
and guidelines for efficiently implementing the block PM. A second advantage of
the the block PM is that it provides a direct way to control the correlation
between the logarithms of the estimates of the likelihood at the current and
proposed values of the parameters than the implementation in Deligiannidis et
al. (2016). We obtain methods and guidelines for selecting the optimal number
of samples based on idealized but realistic assumptions.


title:
Permutation Representations of the Orbits of the Automorphism Group of a
  Finite Module over Discrete Valuation Ring

abstract:
  Consider a discrete valuation ring $R$ whose residue field is finite of
cardinality at least $3$. For a finite torsion module, we consider transitive
subsets $O$ under the action of the automorphism group of the module. We prove
that the associated permutation representation on the complex vector space
$C[O]$ is multiplicity free. This is achieved by obtaining a complete
description of the transitive subsets of $O\times O$ under the diagonal action
of the automorphism group.


title:
Consensus versus persistence of disagreement in opinion formation: the
  role of zealots

abstract:
  We consider a general class of three--state models where individuals hold one
of two opposite opinions, or are neutral, and exchange opinions in generic
pairwise interactions. We show that when opinions spread in a population where
a fraction of individuals (zealots) maintain unshakably their opinion, one of
four qualitatively distinct kinds of collective dynamics arise, depending on
the specific rules governing the social interactions. Unsurprisingly, when
their density is high, zealots drive the whole population to consensus on their
opinion. For low densities a rich phase diagram emerges: a finite population of
dissenters can survive and be the only stationary state or may need a critical
mass or dissenters to be sustained; the critical mass may vanish or not as the
density is reduced; the transition to the high density regime can be smooth or
abrupt, and shows interesting hysteretic effects. For each choice of the
interaction rules we calculate the critical density of zealots above which
diverse opinions cannot survive.


title: Extracting Arabic Relations from the Web

abstract:
  The goal of this research is to extract a large list or table from named
entities and relations in a specific domain. A small set of a handful of
instance relations is required as input from the user. The system exploits
summaries from Google search engine as a source text. These instances are used
to extract patterns. The output is a set of new entities and their relations.
The results from four experiments show that precision and recall varies
according to relation type. Precision ranges from 0.61 to 0.75 while recall
ranges from 0.71 to 0.83. The best result is obtained for (player, club)
relationship, 0.72 and 0.83 for precision and recall respectively.


title: Modal operators for meet-complemented lattices

abstract:
  We investigate some modal operators of necessity and possibility in the
context of meet-complemented (not necessarily distributive) lattices. We
proceed in stages. We compare our operators with others.


title: Challenges in Nuclear Structure Theory

abstract:
  The goal of nuclear structure theory is to build a comprehensive microscopic
framework in which properties of nuclei and extended nuclear matter, and
nuclear reactions and decays can all be consistently described. Due to novel
theoretical concepts, breakthroughs in the experimentation with rare isotopes,
increased exchange of ideas across different research areas, and the progress
in computer technologies and numerical algorithms, nuclear theorists have been
quite successful in solving various bits and pieces of the nuclear many-body
puzzle and the prospects are exciting. This article contains a brief, personal
perspective on the status of the field.


title: Effective Capacity in Broadcast Channels with Arbitrary Inputs

abstract:
  We consider a broadcast scenario where one transmitter communicates with two
receivers under quality-of-service constraints. The transmitter initially
employs superposition coding strategies with arbitrarily distributed signals
and sends data to both receivers. Regarding the channel state conditions, the
receivers perform successive interference cancellation to decode their own
data. We express the effective capacity region that provides the maximum
allowable sustainable data arrival rate region at the transmitter buffer or
buffers. Given an average transmission power limit, we provide a two-step
approach to obtain the optimal power allocation policies that maximize the
effective capacity region. Then, we characterize the optimal decoding regions
at the receivers in the space spanned by the channel fading power values. We
finally substantiate our results with numerical presentations.


title:
Photometric evolution of the 2016 outburst of recurrent Nova LMC 1968:
  the first three weeks

abstract:
  Optical (BVRI) photometry of the first three weeks of the 2016 outburst of
the recurrent Nova LMC 1968 is presented and discussed. The 2016 I-band
light-curve is an exact replica, even in the most minute details, of that for
the 2010 eruption. The maximum is inferred to have occurred on 2016 Jan 21.2 at
I=11.5 mag, corresponding to an absolute magnitude M(I)=-7.15. A ~1 day plateau
is present in all bands about six days past optical maximum, simultaneous with
the emergence of super-soft X-ray emission in Swift observations, signalling
the widespread ionization of the ejecta. The nova entered a much longer plateau
about 9 days past maximum, governed by the brightness of the white dwarf, now
directly visible and still nuclearly burning on its surface. An outburst
recurrence mean period of ~955 days (2.6 yrs) would fit both the OGLE
inter-season gaps and the observed intervals between previous outburts.


title: Clifford theory for glider representations

abstract:
  Classical Clifford theory studies the decomposition of simple $G$-modules
into simple $H$-modules for some normal subgroup $H \triangleleft G$. In this
paper we deal with chains of normal subgroups $1 \triangleleft G_1
\triangleleft \cdots \triangleleft G_d =G$, which allow to consider fragments
and in particular glider representations. These are given by a descending chain
of vector spaces over some field $K$ and relate different representations of
the groups appearing in the chain. Picking some normal subgroup $H
\triangleleft G$ one obtains a normal subchain and one can construct an induced
fragment structure. Moreover, a notion of irreducibility of fragments is
introduced, which completes the list of ingredients to perform a Clifford
theory.


title:
A Bayesian non-parametric method for clustering high-dimensional binary
  data

abstract:
  In many real life problems, objects are described by large number of binary
features. For instance, documents are characterized by presence or absence of
certain keywords; cancer patients are characterized by presence or absence of
certain mutations etc. In such cases, grouping together similar
objects/profiles based on such high dimensional binary features is desirable,
but challenging. Here, I present a Bayesian non parametric algorithm for
clustering high dimensional binary data. It uses a Dirichlet Process (DP)
mixture model and simulated annealing to not only cluster binary data, but also
find optimal number of clusters in the data. The performance of the algorithm
was evaluated and compared with other algorithms using simulated datasets. It
outperformed all other clustering methods that were tested in the simulation
studies. It was also used to cluster real datasets arising from document
analysis, handwritten image analysis and cancer research. It successfully
divided a set of documents based on their topics, hand written images based on
different styles of writing digits and identified tissue and mutation
specificity of chemotherapy treatments.


title:
Weak (anti)localization in tubular semiconductor nanowires with
  spin-orbit coupling

abstract:
  We compute analytically the weak (anti)localization correction to the Drude
conductivity for electrons in tubular semiconductor systems of zinc blende
type. We include linear Rashba and Dresselhaus spin-orbit coupling (SOC) and
compare wires of standard growth directions $\langle100\rangle$,
$\langle111\rangle$, and $\langle110\rangle$. The motion on the
quasi-two-dimensional surface is considered diffusive in both directions:
transversal as well as along the cylinder axis. It is shown that Dresselhaus
and Rashba SOC similarly affect the spin relaxation rates. For the
$\langle110\rangle$ growth direction, the long-lived spin states are of helical
nature. We detect a crossover from weak localization to weak anti-localization
depending on spin-orbit coupling strength as well as dephasing and scattering
rate. The theory is fitted to experimental data of an undoped
$\langle111\rangle$ InAs nanowire device which exhibits a top-gate-controlled
crossover from positive to negative magnetoconductivity. Thereby, we extract
transport parameters where we quantify the distinct types of SOC individually.


title: Which spectral distortions does $\Lambda$CDM actually predict?

abstract:
  Ever refined cosmological measurements have established the $\Lambda$CDM
concordance model, with the key cosmological parameters being determined to
percent-level precision today. This allows us to make explicit predictions for
the spectral distortions of the cosmic microwave background (CMB) created by
various processes occurring in the early Universe. Here, we summarize all
guaranteed CMB distortions and assess their total uncertainty within
$\Lambda$CDM. We also compare simple methods for approximating them,
highlighting some of the subtle aspects when it comes to interpreting future
distortion measurements. Under simplified assumptions, we briefly study how
well a PIXIE-like experiment may measure the main distortion parameters (i.e.,
$\mu$ and $y$). Next generation CMB spectrometers are expected to detect the
distortion caused by reionization and structure formation at extremely high
significance. They will also be able to constrain the small-scale power
spectrum through the associated $\mu$-distortion, improving limits on running
of the spectral index. Distortions from the recombination era, adiabatic
cooling of matter relative to the CMB and dark matter annihilation require a
higher sensitivity than PIXIE in its current design. The crucial next step is
an improved modeling of foregrounds and instrumental aspects, as we briefly
discuss here.


title:
Transit times and mean ages for nonautonomous and autonomous
  compartmental systems

abstract:
  We develop a theory for transit times and mean ages for nonautonomous
compartmental systems. Using the McKendrick-von F\"orster equation, we show
that the mean ages of mass in a compartmental system satisfy a linear
nonautonomous ordinary differential equation that is exponentially stable. We
then define a nonautonomous version of transit time as the mean age of mass
leaving the compartmental system at a particular time and show that our
nonautonomous theory generalises the autonomous case. We apply these results to
study a nine-dimensional nonautonomous compartmental system modeling the
terrestrial carbon cycle, which is a modification of the Carnegie-Ames-Stanford
approach (CASA) model, and we demonstrate that the nonautonomous versions of
transit time and mean age differ significantly from the autonomous quantities
when calculated for that model.


title: Analysis of the strong decay $X(5568) \to B_s^0\pi^+$ with QCD sum rules

abstract:
  In this article, we take the $X(5568)$ to be the scalar diquark-antidiquark
type tetraquark state, study the hadronic coupling constant $g_{XB_s\pi}$ with
the three-point QCD sum rules by carrying out the operator product expansion up
to the vacuum condensates of dimension-6 and including both the connected and
disconnected Feynman diagrams, then calculate the partial decay width of the
strong decay $ X(5568) \to B_s^0 \pi^+$ and obtain the value
$\Gamma_X=\left(20.5\pm8.1\right)\,\rm{MeV}$, which is consistent with the
experimental data $\Gamma_X = \left(21.9 \pm 6.4
{}^{+5.0}_{-2.5}\right)\,\rm{MeV}$ from the D0 collaboration.


title: A microscopic continuum model for defect dynamics in metallic glasses

abstract:
  Motivated by results of the topological theory of glasses accounting for
geometric frustration, we develop the simplest possible continuum mechanical
model of defect dynamics in metallic glasses that accounts for topological,
energetic, and kinetic ideas. The model is aimed towards the development of a
microscopic understanding of the plasticity of such materials. We discuss the
expected predictive capabilities of the model vis-a-vis some observed physical
behaviors of metallic glasses.


title: Elementary equivalences and accessible functors

abstract:
  We introduce the notion of $\lambda$-equivalence and $\lambda$-embeddings of
objects in suitable categories. This notion specializes to
$L_{\infty\lambda}$-equivalence and $L_{\infty\lambda}$-elementary embedding
for categories of structures in a language of arity less than $\lambda$, and
interacts well with functors and $\lambda$-directed colimits. We recover and
extend results of Feferman and Eklof on "local functors" without fixing a
language in advance. This is convenient for formalizing Lefschetz's principle
in algebraic geometry, which was one of the main applications of the work of
Eklof.


title: Mixture Proportion Estimation via Kernel Embedding of Distributions

abstract:
  Mixture proportion estimation (MPE) is the problem of estimating the weight
of a component distribution in a mixture, given samples from the mixture and
component. This problem constitutes a key part in many "weakly supervised
learning" problems like learning with positive and unlabelled samples, learning
with label noise, anomaly detection and crowdsourcing. While there have been
several methods proposed to solve this problem, to the best of our knowledge no
efficient algorithm with a proven convergence rate towards the true proportion
exists for this problem. We fill this gap by constructing a provably correct
algorithm for MPE, and derive convergence rates under certain assumptions on
the distribution. Our method is based on embedding distributions onto an RKHS,
and implementing it only requires solving a simple convex quadratic programming
problem a few times. We run our algorithm on several standard classification
datasets, and demonstrate that it performs comparably to or better than other
algorithms on most datasets.


title: Jumping Jupiter can explain Mercury's orbit

abstract:
  The orbit of Mercury has large values of eccentricity and inclination that
cannot be easily explained if this planet formed on a circular and coplanar
orbit. Here, we study the evolution of Mercury's orbit during the instability
related to the migration of the giant planets in the framework of the jumping
Jupiter model. We found that some instability models are able to produce the
correct values of Mercury's eccentricity and inclination, provided that
relativistic effects are included in the precession of Mercury's perihelion.
The orbital excitation is driven by the fast change of the normal oscillation
modes of the system corresponding to the perihelion precession of Jupiter (for
the eccentricity), and the nodal regression of Uranus (for the inclination).


title:
Particle identification performance of the prototype Aerogel RICH
  counter for the Belle II experiment

abstract:
  We have developed a new type of particle identification device, called an
Aerogel Ring Imaging Cherenkov (ARICH) counter, for the Belle II experiment. It
uses silica aerogel tiles as Cherenkov radiators. For detection of Cherenkov
photons, Hybrid Avalanche Photo-Detectors (HAPDs) are used. The designed HAPD
has a high sensitivity to single photons under a strong magnetic field. We have
confirmed that the HAPD provides high efficiency for single-photon detection
even after exposure to neutron and gamma-ray radiation that exceeds the levels
expected in the 10-year Belle II operation. In order to confirm the basic
performance of the ARICH counter system, we carried out a beam test at the DESY
using a prototype of the ARICH counter with six HAPD modules. The results are
in agreement with our expectations and confirm the suitability of the ARICH
counter for the Belle II experiment. Based on the in-beam performance of the
device, we expect that the identification efficiency at 3.5 GeV/c is 97.4% and
4.9% for pions and kaons, respectively. This paper summarizes the development
of the HAPD for the ARICH and the evaluation of the performance of the
prototype ARICH counter built with the final design components.


title: The Erdos-Posa Property for Directed Graphs

abstract:
  A classical result by Erdos and Posa states that there is a function $f:
{\mathbb N} \rightarrow {\mathbb N}$ such that for every $k$, every graph $G$
contains $k$ pairwise vertex disjoint cycles or a set $T$ of at most $f(k)$
vertices such that $G-T$ is acyclic. The generalisation of this result to
directed graphs is known as Younger's conjecture and was proved by Reed,
Robertson, Seymour and Thomas in 1996. This so-called Erdos-Posa-property can
naturally be generalised to arbitrary graphs and digraphs. Robertson and
Seymour proved that a graph $H$ has the Erdos-Posa-property if, and only if,
$H$ is planar. In this paper we study the corresponding problem for digraphs.
We obtain a complete characterisation of the class of strongly connected
digraphs which have the Erdos-Posa-property (both for topological and butterfly
minors). We also generalise this result to classes of digraphs which are not
strongly connected. In particular, we study the class of vertex-cyclic digraphs
(digraphs without trivial strong components). For this natural class of
digraphs we obtain a nearly complete characterisation of the digraphs within
this class with the Erdos-Posa-property. In particular we give positive and
algorithmic examples of digraphs with the Erdos-Posa-property by using directed
tree decompositions in a novel way.


title:
A giant quiescent solar filament observed with high-resolution
  spectroscopy

abstract:
  A giant, quiet-Sun filament was observed with the high-resolution Echelle
spectrograph at the Vacuum Tower Telescope at Observatorio del Teide on 2011
November 15. A mosaic of spectra (10 maps of 100" X 182") was recorded
simultaneously in the chromospheric absorption lines H-alpha and Na I D2.
Physical parameters of the filament plasma were derived using Cloud Model (CM)
inversions and line core fits. The spectra were complemented with full-disk
filtergrams (He I 10830 A, H-alpha, and Ca II K) of the Chromspheric Telescope
(ChroTel) and full-disk magnetograms of HMI. The filament had extremely large
linear dimensions (817"), which corresponds to about 658 Mm along a great
circle on the solar surface. A total amount of 175119 H-alpha contrast profiles
were inverted using the CM approach. The inferred mean line-of-sight (LOS)
velocity, Doppler width, and source function were similar to previous works of
smaller quiescent filaments. However, the derived optical thickness was larger.
LOS velocity trends inferred from the H-alpha line core fits were in accord,
but smaller, than the ones obtained with CM inversions. Signatures of
counter-streaming flows were detected in the filament.The largest conglomerates
of brightenings in the line core of Na I D2 coincided well with small-scale
magnetic fields as seen by HMI. Mixed magnetic polarities were detected close
to the ends of barbs. The computation of photospheric horizontal flows based on
HMI magnetograms revealed flow kernels with a size of 5-8 Mm and velocities of
0.30-0.45 km/s at the ends of the filament. The physical properties of
extremely large filaments are similar to their smaller counterparts, except for
the optical thickness which in our sample was found to be larger. We found that
a part of the filament, which erupted the day before, is in the process of
reestablishing its initial configuration.


title:
Joint law of the hitting time, overshoot and undershoot for a L\'evy
  process

abstract:
  Let be $(X_t, t\geq 0)$ be a L\'evy process which is the sum of a Brownian
motion with drift and a compound Poisson process. We consider the first passage
time $\tau_x$ at a fixed level $x>0$ by $(X_t, t\geq 0)$ and $K_x:=
X_{\tau_x}-x$ the overshoot and $L_x:= x-X_{\tau_x^-}$ the undershoot. We first
study the regularity of the density of the first passage time. Secondly, we
calculate the joint law of $(\tau_x, K_x, L_x).$


title: Phonon instability of insulating states in optical lattices

abstract:
  The influence of collective phonon excitations, due to intersite atomic
interactions, on the stability of optical lattices is analyzed. These phonon
excitations are shown to essentially reduce the ability of atoms to be
localized. The states that seem to be insulating in the absence of the phonon
excitations can become delocalized when the latter are present. The
delocalization effect exists for both long-range as well as local atomic
interactions.


title: Jacobi's Inversion Problem for Genus Two Hyperelliptic Integral

abstract:
  Hinted by the elliptic parameterization of the Ising model, the addition
formula of the elliptic function forms to give the integrable SU(2) group
relation in the previous paper. We then expect that the addition formula of the
Abelian function with any genus will form to give some integrable Lie group
structure. In this paper, we study Jacobi's inversion problem for hyperelliptic
integral with genus two and we expect some SU(2) structure for the addition
formula of the hyperelliptic theta function with genus two.


title:
Coherent states on quaternion Slices and a measurable field of Hilbert
  spaces

abstract:
  A set of reproducing kernel Hilbert spaces are obtained on Hilbert spaces
over quaternion slices with the aid of coherent states. It is proved that the
so obtained set forms a measurable field of Hilbert spaces and their direct
integral appears again as a reproducing kernel Hilbert space for a bigger
Hilbert space over the whole quaternions. Hilbert spaces over quaternion slices
are identified as representation spaces for a set of irreducible unitary group
representations and their direct integral is shown to be a reducible
representation for the Hilbert space over the whole quaternion field.


title: Sunspot group tilt angle measurements from historical observations

abstract:
  Sunspot positions from various historical sets of solar drawings are analysed
with respect to the tilt angles of bipolar sunspot groups. Data by Scheiner,
Hevelius, Staudacher, Zucconi, Schwabe, and Spoerer deliver a series of average
tilt angles spanning a period of 270 years, additional to previously found
values for 20th-century data obtained by other authors. We find that the
average tilt angles before the Maunder minimum were not significantly different
from the modern values. However, the average tilt angles of a period 50 years
after the Maunder minimum, namely for cycles 0 and 1, were much lower and near
zero. The normal tilt angles before the Maunder minimum suggest that it was not
abnormally low tilt angles which drove the solar cycle into a grand minimum.


title: Plasma-driven ultrashort bunch diagnostic

abstract:
  Ultrashort electron bunches are crucial for an increasing number of
applications, however, diagnosing their longitudinal phase space remains a
challenge. We propose a new method that harnesses the strong electric fields
present in a laser driven plasma wakefield. By transversely displacing driver
laser and witness bunch, a streaking field is applied to the bunch. This field
maps the time information to a transverse momentum change and, consequently, to
a change of transverse position. We illustrate our method with simulations
where we achieve a time resolution in the attosecond range.


title:
Population synthesis of RR Lyrae stars in the original $Kepler$ and $K2$
  Fields of View

abstract:
  It is interesting to ask what fraction of the total available RR Lyrae (RRL)
sample that falls in the $Kepler$ and $K2$ Fields of View (FoV) is known or
discovered. In order assess the completeness of our sample we compared the
known RRL sample in the $Kepler$ and $K2$ fields with synthetic Galactic
models. The Catalina Sky Survey RRL sample was used to calibrate our method. We
found that a large number of faint RRL stars is missing from $Kepler$ and $K2$
fields.


title:
Tapering the sky response for angular power spectrum estimation from
  low-frequency radio-interferometric data

abstract:
  It is important to correctly subtract point sources from
radio-interferometric data in order to measure the power spectrum of diffuse
radiation like the Galactic synchrotron or the Epoch of Reionization 21-cm
signal. It is computationally very expensive and challenging to image a very
large area and accurately subtract all the point sources from the image. The
problem is particularly severe at the sidelobes and the outer parts of the main
lobe where the antenna response is highly frequency dependent and the
calibration also differs from that of the phase center. Here we show that it is
possible to overcome this problem by tapering the sky response. Using simulated
150 MHz observations, we demonstrate that it is possible to suppress the
contribution due to point sources from the outer parts by using the Tapered
Gridded Estimator to measure the angular power spectrum C_l of the sky signal.
We also show from the simulation that this method can self-consistently compute
the noise bias and accurately subtract it to provide an unbiased estimation of
C_l.


title: Variational Autoencoders for Semi-supervised Text Classification

abstract:
  Although semi-supervised variational autoencoder (SemiVAE) works in image
classification task, it fails in text classification task if using vanilla LSTM
as its decoder. From a perspective of reinforcement learning, it is verified
that the decoder's capability to distinguish between different categorical
labels is essential. Therefore, Semi-supervised Sequential Variational
Autoencoder (SSVAE) is proposed, which increases the capability by feeding
label into its decoder RNN at each time-step. Two specific decoder structures
are investigated and both of them are verified to be effective. Besides, in
order to reduce the computational complexity in training, a novel optimization
method is proposed, which estimates the gradient of the unlabeled objective
function by sampling, along with two variance reduction techniques.
Experimental results on Large Movie Review Dataset (IMDB) and AG's News corpus
show that the proposed approach significantly improves the classification
accuracy compared with pure-supervised classifiers, and achieves competitive
performance against previous advanced methods. State-of-the-art results can be
obtained by integrating other pretraining-based methods.


title:
A systematic study of the initial state in heavy ion collisions based on
  the quark participant assumption

abstract:
  We investigate the initial state geometric quantities of heavy ion collisions
based on the quark participant assumption in the Glauber multiple scattering
approach. A systematic comparison to the nucleon participant assumption has
been presented and confronted with the charged multiplicity measurements in
various collision systems. It is found that the quark participant based
assumption can be important to understand the data in multiplicity production
and the initial spatial eccentricity in small systems.


title: Nested sampling, statistical physics and the Potts model

abstract:
  We present a systematic study of the nested sampling algorithm based on the
example of the Potts model. This model, which exhibits a first order phase
transition for $q>4$, exemplifies a generic numerical challenge in statistical
physics: The evaluation of the partition function and thermodynamic
observables, which involve high dimensional sums of sharply structured
multi-modal density functions. It poses a major challenge to most standard
numerical techniques, such as Markov Chain Monte Carlo. In this paper we will
demonstrate that nested sampling is particularly suited for such problems and
it has a couple of advantages. For calculating the partition function of the
Potts model with $N$ sites: a) one run stops after $O(N)$ moves, so it takes
$O(N^{2})$ operations for the run, b) only a single run is required to compute
the partition function along with the assignment of confidence intervals, c)
the confidence intervals of the logarithmic partition function decrease with
$1/\sqrt{N}$ and d) a single run allows to compute quantities for all
temperatures while the autocorrelation time is very small, irrespective of
temperature. Thermodynamic expectation values of observables, which are
completely determined by the bond configuration in the representation of
Fortuin and Kasteleyn, like the Helmholtz free energy, the internal energy as
well as the entropy and heat capacity, can be calculated in the same single run
needed for the partition function along with their confidence intervals. In
contrast, thermodynamic expectation values of magnetic properties like the
magnetization and the magnetic susceptibility require sampling the additional
spin degree of freedom. Results and performance are studied in detail and
compared with those obtained with multi-canonical sampling. Eventually the
implications of the findings on a parallel implementation of nested sampling
are outlined.


title:
Quasiparticle scattering interference in iron pnictides: A probe of the
  origin of nematicity

abstract:
  In this paper, we investigate the quasiparticle scattering interference(QPI)
in the nematic phase of iron pnictides, based on the magnetic and orbital
scenarios of nematicity, respectively. In the spin density wave(SDW) state, the
QPI pattern exhibits a dimer structure in the energy region of the SDW gap,
with its orientation along the ferromagnetic direction of the SDW order. When
the energy is increased to be near the Fermi level, it exhibits two sets of
dimers along the same direction. The dimer structure of the QPI patterns
persists with the decrease of the SDW correlation length in the magnetic driven
nematic phase, although it tends to merge together for the scattering patterns
with energies close to the Fermi level. While in the orbital scenario, the QPI
patterns exhibit a dimer structure in a wide energy region. It undergoes a
{\pi}/2 rotation with the increasing of energy, which is associated with the
inequivalent energies of the two Dirac nodes induced by the orbital order.
These distinct features may be used to probe or distinguish two kinds of
scenarios of the nemeticity.


title: A New Method to Visualize Deep Neural Networks

abstract:
  We present a method for visualising the response of a deep neural network to
a specific input. For image data for instance our method will highlight areas
that provide evidence in favor of, and against choosing a certain class. The
method overcomes several shortcomings of previous methods and provides great
additional insight into the decision making process of convolutional networks,
which is important both to improve models and to accelerate the adoption of
such methods in e.g. medicine. In experiments on ImageNet data, we illustrate
how the method works and can be applied in different ways to understand deep
neural nets.


title:
Ballistic conductivity of graphene channel with p-n junction on
  ferroelectric domain wall

abstract:
  We study the impact of the ferroelectric domain wall on the ballistic
conductance of the single-layer graphene channel in the heterostructure
graphene / physical gap / ferroelectric film using Wentzel-Kramers-Brillouin
approximation. Both self-consistent numerical modeling of the electric field
and space charge dynamics in the heterostructure and approximate analytical
theory show that the domain wall contact with the surface creates p-n junction
in graphene channel. We calculated that the carriers' concentration induced in
graphene by uncompensated ferroelectric dipoles originated from the spontaneous
polarization abrupt near the surface can reach the values of 1019 m-2 order,
which is in two orders higher than it can be obtained for the gate doped
graphene on non-ferroelectric substrates. Therefore we predict that graphene
channel with the p-n junction caused by ferroelectric domain wall would be
characterized by rather high ballistic conductivity.


title:
Antiferromagnetic spin chain behavior and a transition to 3D magnetic
  order in Cu(D,L-alanine)2: Roles of H-bonds

abstract:
  We study the spin chain behavior, a transition to 3D magnetic order and the
magnitudes of the exchange interactions for the metal-amino acid complex
Cu(D,L-alanine)2.H2O, a model compound to investigate exchange couplings
supported by chemical paths characteristic of biomolecules. Thermal and
magnetic data were obtained as a function of temperature (T) and magnetic field
(B0). The magnetic contribution to the specific heat, measured between 0.48 and
30 K, displays above 1.8 K a 1D spin-chain behavior that can be fitted with an
intrachain antiferromagnetic (AFM) exchange coupling constant 2J0 = (-2.12
$\pm$ 0.08) cm$^{-1}$, between neighbor coppers at 4.49 {\AA} along chains
connected by non-covalent and H-bonds. We also observe a narrow specific heat
peak at 0.89 K indicating a phase transition to a 3D magnetically ordered
phase. Magnetization curves at fixed T = 2, 4 and 7 K with B0 between 0 and 9
T, and at T between 2 and 300 K with several fixed values of B0 were globally
fitted by an intrachain AFM exchange coupling constant 2J0 = (-2.27 $\pm$ 0.02)
cm$^{-1}$ and g = 2.091 $\pm$ 0.005. Interchain interactions J1 between coppers
in neighbor chains connected through long chemical paths with total length of
9.51 {\AA} are estimated within the range 0.1 < |2J1| < 0.4 cm$^{-1}$, covering
the predictions of various approximations. We analyze the magnitudes of 2J0 and
2J1 in terms of the structure of the corresponding chemical paths. The main
contribution in supporting the intrachain interaction is assigned to H-bonds
while the interchain interactions are supported by paths containing H-bonds and
carboxylate bridges, with the role of the H-bonds being predominant. We compare
the obtained intrachain coupling with studies of compounds showing similar
behavior and discuss the validity of the approximations allowing to calculate
the interchain interactions.


title: Tensor Product Multiplicities via Upper Cluster Algebras

abstract:
  For each valued quiver $Q$ of Dynkin type, we construct a valued ice quiver
$\Delta_Q^2$. Let $G$ be a simple connected Lie group with Dynkin diagram the
underlying valued graph of $Q$. The upper cluster algebra of $\Delta_Q^2$ is
graded by the triple dominant weights $(\mu,\nu,\lambda)$ of $G$. We prove that
when $G$ is simply-laced, the dimension of each graded component counts the
tensor multiplicity $c_{\mu,\nu}^\lambda$. We conjecture that this is also true
if $G$ is not simply-laced, and sketch a possible approach. Using this
construction, we improve Berenstein-Zelevinsky's model, or in some sense
generalize Knutson-Tao's hive model in type $A$.


title:
Decoherence by spontaneous emission: a single-atom analog of
  superradiance

abstract:
  We show that the stationary decoherence rate of an open quantum system can be
decomposed as a sum of local and nonlocal contributions, respectively related
to the strength of the coupling between system and environment, and to the
quality of the information about the system leaking into the environment. Both
terms arise naturally in the framework of the influence functional, with the
nonlocal term arising from the coupling between the backward and forward
histories describing the open quantum system time evolution. While the local
contribution always yields a positive decoherence rate, the nonlocal one may
lead to recoherence when only partial information about the system is obtained
from the disturbed environment. We illustrate these concepts in the framework
of interferometry with trapped atoms, by analyzing the effect of spontaneous
emission on the coherence of the center-of-mass.


title:
Verification of an analytic fit for the vortex core profile in
  superfluid Fermi gases

abstract:
  A characteristic property of superfluidity and -conductivity is the presence
of quantized vortices in rotating systems. To study the BEC-BCS crossover the
two most common methods are the Bogoliubov-De Gennes theory and the usage of an
effective field theory. In order to simplify the calculations for one vortex,
it is often assumed that the hyperbolic tangent yields a good approximation for
the vortex structure. The combination of a variational vortex structure,
together with cylindrical symmetry yields analytic (or numerically simple)
expressions. The focus of this article is to investigate to what extent this
analytic fit truly reflects the vortex structure throughout the BEC-BCS
crossover at finite temperatures. The vortex structure will be determined using
the effective field theory presented in [Eur. Phys. Journal B 88, 122 (2015)]
and compared to the variational analytic solution. By doing this it is possible
to see where these two structures agree, and where they differ. This comparison
results in a range of applicability where the hyperbolic tangent will be a good
fit for the vortex structure.


title:
Robust multigrid for high-order discontinuous Galerkin methods: A fast
  Poisson solver suitable for high-aspect ratio Cartesian grids

abstract:
  We present a polynomial multigrid method for nodal interior penalty and local
discontinuous Galerkin formulations of the Poisson equation on Cartesian grids.
For smoothing we propose two classes of overlapping Schwarz methods. The first
class comprises element-centered and the second face-centered methods. Within
both classes we identify methods that achieve superior convergence rates, prove
robust with respect to the mesh spacing and the polynomial order, at least up
to ${P=32}$. Consequent structure exploitation yields a computational
complexity of $O(PN)$, where $N$ is the number of unknowns. Further we
demonstrate the suitability of the face-centered method for element aspect
ratios up to 32.


title: A minimum-change version of the Chung-Feller theorem for Dyck paths

abstract:
  A Dyck path with $2k$ steps and $e$ flaws is a path in the integer lattice
that starts at the origin and consists of $k$ many $\nearrow$-steps and $k$
many $\searrow$-steps that change the current coordinate by $(1,1)$ or
$(1,-1)$, respectively, and that has exactly $e$ many $\searrow$-steps below
the line $y=0$. Denoting by $D_{2k}^e$ the set of Dyck paths with $2k$ steps
and $e$ flaws, the Chung-Feller theorem asserts that the sets
$D_{2k}^0,D_{2k}^1,\ldots,D_{2k}^k$ all have the same cardinality
$\frac{1}{k+1}\binom{2k}{k}=C_k$, the $k$-th Catalan number. The standard
combinatorial proof of this classical result establishes a bijection $f'$
between $D_{2k}^e$ and $D_{2k}^{e+1}$ that swaps certain parts of the given
Dyck path $x$, with the effect that $x$ and $f'(x)$ may differ in many
positions. In this paper we strengthen the Chung-Feller theorem by presenting a
simple bijection $f$ between $D_{2k}^e$ and $D_{2k}^{e+1}$ which has the
additional feature that $x$ and $f(x)$ differ in only two positions (the least
possible number). We also present an algorithm that allows to compute a
sequence of applications of $f$ in constant time per generated Dyck path. As an
application, we use our minimum-change bijection $f$ to construct cycle-factors
in the odd graph $O_{2k+1}$ and the middle levels graph $M_{2k+1}$ --- two
intensively studied families of vertex-transitive graphs --- that consist of
$C_k$ many cycles of the same length.


title: Testing fine-grained parallelism for the ADMM on a factor-graph

abstract:
  There is an ongoing effort to develop tools that apply distributed
computational resources to tackle large problems or reduce the time to solve
them. In this context, the Alternating Direction Method of Multipliers (ADMM)
arises as a method that can exploit distributed resources like the dual ascent
method and has the robustness and improved convergence of the augmented
Lagrangian method. Traditional approaches to accelerate the ADMM using multiple
cores are problem-specific and often require multi-core programming. By
contrast, we propose a problem-independent scheme of accelerating the ADMM that
does not require the user to write any parallel code. We show that this scheme,
an interpretation of the ADMM as a message-passing algorithm on a factor-graph,
can automatically exploit fine-grained parallelism both in GPUs and
shared-memory multi-core computers and achieves significant speedup in such
diverse application domains as combinatorial optimization, machine learning,
and optimal control. Specifically, we obtain 10-18x speedup using a GPU, and
5-9x using multiple CPU cores, over a serial, optimized C-version of the ADMM,
which is similar to the typical speedup reported for existing GPU-accelerated
libraries, including cuFFT (19x), cuBLAS (17x), and cuRAND (8x).


title:
Large deviations for the two-dimensional stochastic Navier-Stokes
  equation with vanishing noise correlation

abstract:
  We are dealing with the validity of a large deviation principle for the
two-dimensional Navier-Stokes equation, with periodic boundary conditions,
perturbed by a Gaussian random forcing. We are here interested in the regime
where both the strength of the noise and its correlation are vanishing, on a
length scale $\e$ and $\d(\e)$, respectively, with $0<\e,\ \d(\e)<<1$.
Depending on the relationship between $\e$ and $\d(\e)$ we will prove the
validity of the large deviation principle in different functional spaces.


title:
Index-antiguiding in narrow-ridge GaN-based laser diodes investigated by
  measurements of the current-dependent gain and index spectra and by
  self-consistent simulation

abstract:
  The threshold current density of narrow (1.5 {\mu}m) ridge-waveguide InGaN
multi-quantum-well laser diodes, as well as the shape of their lateral
far-field patterns, strongly depend on the etch depth of the ridge waveguide.
Both effects can be attributed to strong index-antiguiding. A value of the
antiguiding factor R = 10 is experimentally determined near threshold by
measurements of the current-dependent gain and refractive index spectra. The
device performances are simulated self-consistently solving the
Schr\"odinger-Poisson equations and the equations for charge transport and
waveguiding. Assuming a carrier-induced index change which matches the
experimentally determined antiguiding factor, both the measured high threshold
current and the shape of the far-field pattern of lasers with shallow ridges
can be reproduced theoretically.


title:
Chemical and physical characterization of collapsing low-mass prestellar
  dense cores

abstract:
  The first hydrostatic core, also called the first Larson core, is one of the
first steps in low-mass star formation, as predicted by theory. With recent and
future high performance telescopes, details of these first phases become
accessible, and observations may confirm theory and even bring new challenges
for theoreticians. In this context, we study from a theoretical point of view
the chemical and physical evolution of the collapse of prestellar cores until
the formation of the first Larson core, in order to better characterize this
early phase in the star formation process. We couple a state-of-the-art
hydrodynamical model with full gas-grain chemistry, using different assumptions
on the magnetic field strength and orientation. We extract the different
components of each collapsing core (i.e., the central core, the outflow, the
disk, the pseudodisk, and the envelope) to highlight their specific physical
and chemical characteristics. Each component often presents a specific physical
history, as well as a specific chemical evolution. From some species, the
components can clearly be differentiated. The different core models can also be
chemically differentiated. Our simulation suggests some chemical species as
tracers of the different components of a collapsing prestellar dense core, and
as tracers of the magnetic field characteristics of the core. From this result,
we pinpoint promising key chemical species to be observed.


title: Canonical energy and hairy AdS black holes

abstract:
  We propose the modified version of the canonical energy which was introduced
originally by Hollands and Wald. Our construction depends only on the
Euler-Lagrange expression of the system and thus is independent of the
ambiguity in the Lagrangian. After some comments on our construction, we
briefly mention on the relevance of our construction to the boundary
information metric in the context of the AdS/CFT correspondence. We also study
the stability of three-dimensional hairy extremal black holes by using our
construction.


title:
On the pole content of coupled channels chiral approaches used for the
  $\bar{K}N$ system

abstract:
  Several theoretical groups describe the antikaon-nucleon interaction at low
energies within approaches based on the chiral SU(3) dynamics and including
next-to-leading order contributions. We present a comparative analysis of the
pertinent models and discuss in detail their pole contents. It is demonstrated
that the approaches lead to very different predictions for the $K^{-}p$
amplitude extrapolated to subthreshold energies as well as for the $K^{-}n$
amplitude. The origin of the poles generated by the models is traced to the
so-called zero coupling limit, in which the inter-channel couplings are
switched off. This provides new insights into the pole contents of the various
approaches. In particular, different concepts of forming the $\Lambda(1405)$
resonance are revealed and constraints related to the appearance of such poles
in a given approach are discussed.


title:
On the inconsistency of $\ell_1$-penalised sparse precision matrix
  estimation

abstract:
  Various $\ell_1$-penalised estimation methods such as graphical lasso and
CLIME are widely used for sparse precision matrix estimation. Many of these
methods have been shown to be consistent under various quantitative assumptions
about the underlying true covariance matrix. Intuitively, these conditions are
related to situations where the penalty term will dominate the optimisation. In
this paper, we explore the consistency of $\ell_1$-based methods for a class of
sparse latent variable -like models, which are strongly motivated by several
types of applications. We show that all $\ell_1$-based methods fail
dramatically for models with nearly linear dependencies between the variables.
We also study the consistency on models derived from real gene expression data
and note that the assumptions needed for consistency never hold even for modest
sized gene networks and $\ell_1$-based methods also become unreliable in
practice for larger networks.