title: An Empirical Exploration of Skip Connections for Sequential Tagging

abstract:
  In this paper, we empirically explore the effects of various kinds of skip
connections in stacked bidirectional LSTMs for sequential tagging. We
investigate three kinds of skip connections connecting to LSTM cells: (a) skip
connections to the gates, (b) skip connections to the internal states and (c)
skip connections to the cell outputs. We present comprehensive experiments
showing that skip connections to cell outputs outperform the remaining two.
Furthermore, we observe that using gated identity functions as skip mappings
works pretty well. Based on this novel skip connections, we successfully train
deep stacked bidirectional LSTM models and obtain state-of-the-art results on
CCG supertagging and comparable results on POS tagging.


title: Wythoffian Skeletal Polyhedra in Ordinary Space, I

abstract:
  Skeletal polyhedra are discrete structures made up of finite, flat or skew,
or infinite, helical or zigzag, polygons as faces, with two faces on each edge
and a circular vertex-figure at each vertex. When a variant of Wythoff's
construction is applied to the forty-eight regular skeletal polyhedra
(Grunbaum-Dress polyhedra) in ordinary space, new highly symmetric skeletal
polyhedra arise as "truncations" of the original polyhedra. These Wythoffians
are vertex-transitive and often feature vertex configurations with an
attractive mix of different face shapes. The present paper describes the
blueprint for the construction and treats the Wythoffians for distinguished
classes of regular polyhedra. The Wythoffians for the remaining classes of
regular polyhedra will be discussed in Part II, by the second author. We also
examine when the construction produces uniform skeletal polyhedra.


title:
Dimensional reduction of the Luttinger Hamiltonian and g-factors of
  holes in symmetric two-dimensional semiconductor heterostructures

abstract:
  The spin-orbit interaction of holes in zinc-blende semiconductors is much
stronger than that of electrons. This makes the hole systems very attractive
for possible spintronics applications. In three dimensions (3D) dynamics of
holes is described by well known Luttinger Hamiltonian. However, most of recent
spintronics applications are related to two dimensional heterostructures where
dynamics in one direction is frozen due to quantum confinement. The confinement
results in dimensional reduction of the Luttinger Hamiltonian, 3D ->2D. Due to
interplay of the spin-orbit interaction, the external magnetic field, and the
lateral gate potential imposed on the heterostructure the reduction is highly
nontrivial and not known. In the present work we perform the reduction and
hence derive the general effective Hamiltonian which describes spintronics
effects in symmetric two-dimensional (2D) heterostructures. In particular, we
do the following, (i) derive the spin-orbit interaction and the Darwin
interaction related to the lateral gate potential, (ii) determine the momentum
dependent out-of-plane g-factor, (iii) point out that there are two independent
in-plane g-factors, (iv) determine momentum dependencies of the in-plane
g-factors.


title:
Dissociation of heavy quarkonium in hot QCD medium in a quasi-particle
  model

abstract:
  Following a recent work on the effective description of the equations of
state for hot QCD obtained from a Hard thermal loop expression for the gluon
self-energy, in terms of the quasi-gluons and quasi- quark/anti-quarks with
respective effective fugacities, the dissociation process of heavy quarkonium
in hot QCD medium has been investigated. This has been done by investigating
the medium modification to a heavy quark potential. The medium modified
potential has a quite different form (a long range Coulomb tail in addition to
the usual Yukawa term) in contrast to the usual picture of Debye screening. The
flavor dependence of the binding energies of the heavy quarkonia states and the
dissociation temperature have been obtained by employing the debye mass for
pure gluonic and full QCD case computed employing the quasi-particle picture.
Thus estimated dissociation patterns of the charmonium and bottomonium states,
considering Debye mass from different approaches in pure gluonic case and full
QCD, have shown good agreement with the other potential model studies.


title:
Topological depletions and sub-leading scalings across topological phase
  transitions

abstract:
  It remains an open problem if there are universal scaling functions across a
topological quantum phase transition (TPT) without an order parameter, but with
extended Fermi surfaces (FS ). Here, we study a simple system of fermions
hopping in a cubic lattice subject to a Weyl type spin-orbit coupling (SOC). As
one tunes the SOC parameter at the half filling, the system displays Weyl
fermions and also various TPT due to the collision of particle-particle or
hole-hole Weyl Fermi Surface (WFS). At the zero temperature, the TPT is found
to be a third order one whose critical exponent is determined. We derive the
scaling functions of the specific heat, compressibility and magnetic
susceptibilities. In contrast to all the previous cases in quantum or
topological transitions, although the leading terms are non-universal and
cutoff dependent, the sub-leading terms satisfy universal scaling relations.
The sub-leading scaling leads to the topological depletions (TD) which show
non-analytic and non-Fermi liquid corrections in the quantum critical regime,
can be easily distinguished from the analytic leading terms and detected
experimentally. One can also form a topological Wilson ratio from the TD of two
conserved quantities such as the specific heat and the compressibility. As a
byproduct, we also find Type II Weyl fermions appearing as the TPT due to the
collision of the extended particle-hole WFS. Experimental realizations and
detections in cold atom systems and materials with SOC are discussed.


title:
Pinned algebraic distances determined by Cartesian products in
  $\mathbb{F}_p^2$

abstract:
  Let $p$ be an odd prime and $A \subseteq \mathbb{F}_p$ be a subset of the
finite field with $p$ elements. We show that $A \times A \subseteq
\mathbb{F}_p^2$ determines at least a constant multiple of $\min\{p,
|A|^{3/2}\}$ distinct pinned algebraic distances.


title: Single 100-terawatt attosecond X-ray light pulse generation

abstract:
  The birth of attosecond light sources is expected to inspire a breakthrough
in ultrafast optics, which may extend human real-time measurement and control
techniques into atomic-scale electronic dynamics. For applications, it is
essential to obtain a single attosecond pulse of high intensity, large photon
energy and short duration. Here we show that single 100-terawatt attosecond
X-ray light pulse with intensity ${1\times10^{21}}\textrm{W}/\textrm{cm}^{{
2}}$ and duration ${7.9} \textrm{as}$ can be produced by intense laser
irradiation on a capacitor-nanofoil target composed of two separate nanofoils.
In the interaction, a strong electrostatic potential develops between two
nanofoils, which drags electrons out of the second foil and piles them up in
vacuum, forming an ultradense relativistic electron nanobunch. This nanobunch
exists in only half a laser cycle and smears out in others, resulting in
coherent synchrotron emission of a single pulse. Such an unprecedentedly giant
attosecond X-ray pulse may bring us to view a real attoworld.


title: Stability longevity and all that : false vacua and topological defects

abstract:
  I present two interesting studies related to the role of solitons in theories
with spontaneous symmetry breaking. Quantised fermions coupled to solitons are
known to induce fractional fermion number. I present an example where an
unstable topological solution binding a zero mode of a majorana fermion gets
stabilised due to the induced fractional number. Thus neither is the cosmic
string stable nor is the fermion number conserved, yet the bound state then
becomes stable due to Quantum Mechanics. The other phenomenon concerns a
metastable vacuum getting destabilised due to the presence of a cosmic string.
This happens because the scalar field signalling spontaneous symmetry breaking
acquires a vacuum expectation value approaching its true vacuum value in the
core of the string. Thus the string acts like a seed nucleating the true
vacuum. The instanton mediating between the false vacuum and the exit point
into the true vacuum is shown to exist and graphically displayed through a
numeric calculation. T. Padmanabhan has been a long time friend and was
collaborator for early investigations in this direction. I review these works
done subsequently with other collaborators as a felicitation to him on his
sixtieth birthday.


title: Comparing of switching frequency on vector controlled asynchronous motor

abstract:
  Nowadays, asynchronous motors have wide range use in many industrial
applications. Field oriented control (FOC) and direct torque control (DTC) are
commonly used methods in high performance vector control for asynchronous
motors. Therefore, it is very important to identify clearly advantages and
disadvantages of both systems in the selection of appropriate control methods
for many industrial applications. This paper aims to present a new and
different perspective regarding the comparison of the switching behaviours on
the FOC and the DTC drivers. For this purpose, the experimental studies have
been carried out to compare the inverter switching frequencies and torque
responses of the asynchronous motor in the FOC and the DTC systems under
different working conditions. The dSPACE 1103 controller board was programmed
with Matlab/Simulink software. As expected, the experimental studies showed
that the FOC controlled motors has a lessened torque ripple. On the other hand,
the FOC controlled motor switching frequency has about 65-75% more than the DTC
controlled under both loaded and unloaded working conditions.


title: NEDindex: A new metric for community structure in networks

abstract:
  There are several metrics (Modularity, Mutual Information, Conductance, etc.)
to evaluate the strength of graph clustering in large graphs. These metrics
have great significance to measure the effectiveness and they are often used to
find the strongly connected clusters with respect to the whole graph. In this
paper, we propose a new metric to evaluate the strength of graph clustering and
also study its applications. We show that our proposed metric has great
consistency which is similar to other metrics and easy to calculate. Our
proposed metric also shows consistency where other metrics fail in some special
cases. We demonstrate that our metric has reasonable strength while extracting
strongly connected communities in both simulated (in silico) data and real data
networks. We also show some comparative results of our proposed metric with
other popular metric(s) for Online Social Networks (OSN) and Gene Regulatory
Networks (GRN).


title:
Network Reconstruction From High Dimensional Ordinary Differential
  Equations

abstract:
  We consider the task of learning a dynamical system from high-dimensional
time-course data. For instance, we might wish to estimate a gene regulatory
network from gene expression data measured at discrete time points. We model
the dynamical system non-parametrically as a system of additive ordinary
differential equations. Most existing methods for parameter estimation in
ordinary differential equations estimate the derivatives from noisy
observations. This is known to be challenging and inefficient. We propose a
novel approach that does not involve derivative estimation. We show that the
proposed method can consistently recover the true network structure even in
high dimensions, and we demonstrate empirical improvement over competing
approaches.


title: Exploring the Hyperchargeless Higgs Triplet Model up to the Planck Scale

abstract:
  We examine an extension of the SM Higgs sector by a Higgs triplet taking into
consideration the Higgs-like particle discovery at the LHC with mass around 125
GeV. We evaluate the bounds on the scalar potential through the unitarity of
the scattering-matrix. Considering with and without $\Z_2$-symmetry on the
extra triplet, we derive constraints on the parameter space. We identify the
region of the parameter space that corresponds to the stability and
metastability of the electroweak vacuum. We also show that at large field
values the scalar potential of this model is suitable to explain inflation.


title: Cloud-Aware Web Service Security: Information Hiding in Cloud Computing

abstract:
  This study concerns the security challenges that the people face in the usage
and implementation of cloud computing. Despite its growth in the past few
decades, this platform has experienced different challenges. They all arise
from the concern of data safety that the nature of sharing in the cloud
presents. This paper looks to identify the benefits of using a cloud computing
platform and the issue of information security. The paper also reviews the
concept of information hiding and its relevance to the cloud. This technique
has two ways about it that impact how people use cloud computing in their
organizations and even for personal implementations. First it presents the
potential to circulate harmful information and files that can adversely affect
the data those users upload on those platforms. It is also the basis of the
strategies such as steganalysis and cryptographic storage architecture that are
essential for data security.


title: Measuring the Effect of CMMI Quality Standard on Agile Scrum Model

abstract:
  Agile development gets more appreciation from the market due to the flexible
nature and more productivity. Among the Agile processes, Scrum gives better
management of the processes, which are practiced in an organization. Though
Scrum process model have several features and strengths but it still lacks in
management and quality. This research deals with the improvement of Scrum
processes for better management and to improve the quality of the software
using the infusion of different practices from internationally renowned quality
standards. Survey is used to validate the proposed framework. Statistical
analysis shows that the proposed research has a profound effect on Scrum model
to develop high quality software.


title:
Toward analytic theory of the Rayleigh-Taylor instability: lessons from
  a toy model

abstract:
  In this work we suggest that a turbulent phase of the Rayleigh-Taylor
instability can be explained as a universal stochastic wave traveling with
constant speed in a properly renormalized system. This wave, originating from
ordinary deterministic chaos in a renormalized time, has two constant limiting
states at both sides. These states are related to the initial discontinuity at
large scales and to stationary turbulence at small scales. The theoretical
analysis is confirmed with extensive numerical simulations made for a new shell
model, which features basic properties of the phenomenological theory for the
Rayleigh-Taylor instability.


title:
wtest: an R Package for Testing Main and Interaction Effect in Genotype
  Data with Binary Traits

abstract:
  This R package evaluates main and pair-wise interaction effect of single
nucleotide polymorphisms (SNPs) via the W-test, scalable to whole genome-wide
data sets. The package provides fast and accurate p-value estimation of genetic
markers, as well as diagnostic checking on the probability distributions. It
allows flexible stage-wise or exhaustive association testing in a user-friendly
interface. Availability: The package is available in CRAN, or from website:
http://www2.ccrb.cuhk.edu.hk/wtest


title: Nanodiamond integration with photonic devices

abstract:
  We discuss the progress in integration of nanodiamonds with photonic devices
for quantum optics applications. Experimental results in GaP, SiO2 and
SiC-nanodiamond platforms show that various regimes of light and matter
interaction can be achieved by engineering color center systems through hybrid
approaches. We present our recent results on the growth of color center-rich
nanodiamond on prefabricated 3C-SiC microdisk resonators. These hybrid devices
achieve up to five-fold enhancement of diamond color center light emission and
can be employed for integrated quantum photonics.


title: Generating Candidate Busy Beaver Machines (Or How to Build the Zany Zoo)

abstract:
  The busy beaver problem is a well-known example of a non-computable function.
In order to determine a particular value of this function, it is necessary to
generate and classify a large number of Turing machines. Previous work on this
problem has described the processes used for the generation and classification
of these machines, but unfortunately has generally not provided details of the
machines considered. While there is no reason to doubt the veracity of the
results known so far, it is difficult to accept such results as scientifically
proven without being able to inspect the appropriate evidence. In addition, a
list of machines and their classifications can be used for other results, such
as variations on the busy beaver problem and related problems such as the
placid platypus problem. In this paper we investigate how to generate classes
of machines to be considered for the busy beaver problem. We discuss the
relationship between quadruple and quintuple variants of Turing machines, and
show that the latter are more general than the former. We give some formal
results to justify our strategy for minimising the number of machines
generated, and define a process reflecting this strategy for generating
machines. We describe our implementation, and the results of generating various
classes of machines with up to 5 states or up to 5 symbols, all of which
(together with our code) are available on the author's website.


title:
A large enhancement of carrier mobility in phosphorene by introducing
  hexagonal boron nitride substrate

abstract:
  Carrier mobility is a crucial character for electronic devices since it
domains power dissipation and switching speed. Materials with certain high
carrier mobility, equally, unveil rich unusual physical phenomena elusive in
their conventional counterparts. As a consequence, the methods to enhance the
carrier mobility of materials receive immense research interests due to their
potential applications in more effective electronic devices and enrichment of
more unusual phenomena. For instance, introducing a flat hexagonal boron
nitride (h-BN) substrate to enhance the carrier mobility has been achieved
experimentally. However, the underlying mechanics is not well understood. In
this study, we estimate the carrier mobility of phosphorene on h-BN substrate
(P/h-BN) within the framework of the phonon-limited scattering model at
first-principles level. %Our results are generic. Besides high-$\kappa$
dielectric property, h-BN also possesses excellent mechanical property of a
high two-dimensional elastic modulus. The P/h-BN heterostructure inherits the
high elastic modulus of h-BN, leading to an enhanced carrier mobility in
phosphorene. Owing to the weak van der Waals interactions between the layers,
the unique electronic properties of phosphorene are almost perfectly preserved
near the Fermi level, guaranteeing the superior electronic transport in P/h-BN.
Our findings offer a new perspective to improve the carrier mobility in
phosphorene as well as other 2D materials based field effect transistors.


title:
The Fefferman-Stein type inequalities for strong and directional maximal
  operators in the plane

abstract:
  The Fefferman-Stein type inequalities for strong maximal operator and
directional maximal operator are verified with composition of the
Hardy-Littlewood maximal operator in the plane.


title: A note on (co)homologies of algebras from unpunctured surfaces

abstract:
  In a previous paper, the author compute the dimension of Hochschild
cohomology groups of Jacobian algebras from (unpunctured) triangulated
surfaces, and gave a geometric interpretation of those numbers in terms of the
number of internal triangles, the number of vertices and the existence of
certain kind of boundaries. The aim of this note is computing the cyclic
(co)homology and the Hochschild homology of the same family of algebras and
giving an interpretation of those dimensions through elements of the
triangulated surface.


title: Spectral disentangling with Spectangular

abstract:
  The paper introduces the software Spectangular for spectral disentangling via
singular value decomposition with global optimisation of the orbital parameters
of the stellar system or radial velocities of the individual observations. We
will describe the procedure and the different options implemented in our
program. Furthermore, we will demonstrate the performance and the applicability
using tests on artificial data. Additionally, we use high-resolution spectra of
Capella to demonstrate the performance of our code on real-world data. The
novelty of this package is the implemented global optimisation algorithm and
the graphical user interface (GUI) for ease of use. We have implemented the
code to tackle SB1 and SB2 systems with the option of also dealing with
telluric (static) lines.


title:
Signatures of phonon and defect-assisted tunneling in planar
  metal-hexagonal boron nitride-graphene junctions

abstract:
  Electron tunneling spectroscopy measurements on van der Waals
heterostructures consisting of metal and graphene (or graphite) electrodes
separated by atomically thin hexagonal boron nitride tunnel barriers are
reported. The tunneling conductance dI/dV at low voltages is relatively weak,
with a strong enhancement reproducibly observed to occur at around |V| ~ 50 mV.
While the weak tunneling at low energies is attributed to the absence of
substantial overlap, in momentum space, of the metal and graphene Fermi
surfaces, the enhancement at higher energies signals the onset of inelastic
processes in which phonons in the heterostructure provide the momentum
necessary to link the Fermi surfaces. Pronounced peaks in the second derivative
of the tunnel current, are observed at voltages where known phonon modes in the
tunnel junction have a high density of states. In addition, features in the
tunneling conductance attributed to single electron charging of nanometer-scale
defects in the boron nitride are also observed in these devices. The small
electronic density of states of graphene allows the charging spectra of these
defect states to be electrostatically tuned, leading to Coulomb diamonds in the
tunneling conductance.


title: DNN based Speaker Recognition on Short Utterances

abstract:
  This paper investigates the effects of limited speech data in the context of
speaker verification using deep neural network (DNN) approach. Being able to
reduce the length of required speech data is important to the development of
speaker verification system in real world applications. The experimental
studies have found that DNN-senone-based Gaussian probabilistic linear
discriminant analysis (GPLDA) system respectively achieves above 50% and 18%
improvements in EER values over GMM-UBM GPLDA system on NIST 2010
coreext-coreext and truncated 15sec-15sec evaluation conditions. Further when
GPLDA model is trained on short-length utterances (30sec) rather than
full-length utterances (2min), DNN-senone GPLDA system achieves above 7%
improvement in EER values on truncated 15sec-15sec condition. This is because
short length development i-vectors have speaker, session and phonetic variation
and GPLDA is able to robustly model those variations. For several real world
applications, longer utterances (2min) can be used for enrollment and shorter
utterances (15sec) are required for verification, and in those conditions,
DNN-senone GPLDA system achieves above 26% improvement in EER values over
GMM-UBM GPLDA systems.


title:
Self-Consistent Field Theory studies of the thermodynamics and quantum
  spin dynamics of magnetic Skyrmions

abstract:
  A self-consistent field theory is introduced and used to investigate the
thermodynamics and spin dynamics of an $S = 1$ quantum spin system with a
magnetic Skyrmion. The temperature dependence of the Skyrmion profile as well
as the phase diagram are calculated. It is shown that the Skyrmion carries a
phase transition to the ferromagnetic phase of first order with increasing
temperature, while the magnetization of the surrounding ferromagnet undergoes a
phase transition of second order when changing to the paramagnetic phase.
Furthermore, the electric field driven annihilation process of the Skyrmion is
described quantum mechanical by solving the time dependent Schr\"odinger
equation. The results are compared with the trajectories of the semi-classical
description of the spin expectation values using a differential equation
similar to the classical Landau-Lifshitz-Gilbert equation.


title:
Numerical computation of triangular cavity flows by a Lagrange-Galerkin
  scheme with a locally linearized velocity

abstract:
  We show numerical results of triangular cavity flow problems solved by a
Lagrange-Galerkin scheme free from numerical quadrature. The scheme has
recently developed by us, where a locally linearized velocity and the backward
Euler approximation are used in finding the position of fluid particle at the
previous time step. Since the scheme can be implemented exactly as it is, the
theoretical stability and convergence results are assured, while the
conventional Lagrange-Galerkin schemes may encounter the instability caused by
numerical quadrature errors. The scheme is employed to solve cavity flow
problems in triangular domains, where we observe the bifurcation of stationary
solutions and the patterns of streamlines.


title:
Linear-Quadratic Optimal Control Problems for Mean-Field Stochastic
  Differential Equations with Jumps

abstract:
  In this paper, we study a linear-quadratic optimal control problem for
mean-field stochastic differential equations driven by a Poisson random
martingale measure and a multidimensional Brownian motion. Firstly, the
existence and uniqueness of the optimal control is obtained by the classic
convex variation principle. Secondly, by the duality method, the optimality
system, also called the stochastic Hamilton system which turns out to be a
linear fully coupled mean-field forward-backward stochastic differential
equation with jumps, is derived to characterize the optimal control. Thirdly,
applying a decoupling technique, we establish the connection between two
Riccati equation and the stochastic Hamilton system and then prove the optimal
control has a state feedback representation.


title: Toda systems and hypergeometric equations

abstract:
  This paper establishes certain existence and classification results for
solutions to $SU(n)$ Toda systems with three singular sources at 0, 1, and
$\infty$. First, we determine the necessary conditions for such an $SU(n)$ Toda
system to be related to an $n$th order hypergeometric equation. Then, we
construct solutions for $SU(n)$ Toda systems that satisfy the necessary
conditions and also the interlacing conditions from Beukers and Heckman.
Finally, for $SU(3)$ Toda systems satisfying the necessary conditions, we
classify, under a natural reality assumption, that all the solutions are
related to hypergeometric equations. This proof uses the Pohozaev identity.


title:
A stable and convergent method for Hodge decomposition of fluid-solid
  interaction

abstract:
  Fluid-solid interaction has been a challenging subject due to their strong
nonlinearity and multidisciplinary nature. Many of the numerical methods for
solving FSI problems have struggled with non-convergence and numerical
instability. In spite of comprehensive studies, it has been still a challenge
to develop a method that guarantees both convergence and stability.
  Our discussion in this work is restricted to the interaction of viscous
incompressible fluid flow and a rigid body. We take the monolithic approach by
Gibou and Min that results in an extended Hodge projection. The projection
updates not only the fluid vector field but also the solid velocities. We
derive the equivalence of the extended Hodge projection to the Poisson equation
with non-local Robin boundary condition. We prove the existence, uniqueness,
and regularity for the weak solution of the Poisson equation, through which the
Hodge projection is shown to be unique and orthogonal. Also, we show the
stability of the projection in a sense that the projection does not increase
the total kinetic energy of fluid and solid. Also, we discusse a numerical
method as a discrete analogue to the Hodge projection, then we show that the
unique decomposition and orthogonality also hold in the discrete setting. As
one of our main results, we prove that the numerical solution is convergent
with at least the first order accuracy. We carry out numerical experiments in
two and three dimensions, which validate our analysis and arguments.


title:
Preconditioners and Their Analyses for Edge Element Saddle-point Systems
  Arising from Time-harmonic Maxwell Equations

abstract:
  We shall propose and analyze some new preconditioners for the saddle-point
systems arising from the edge element discretization of the time-harmonic
Maxwell equations in three dimensions. We will first consider the saddle-point
systems with vanishing wave number, for which we present an important relation
between the solutions of the singular curl-curl system and the non-singular
saddle-point system, then demonstrate that the saddle-point system can be
efficiently solved by the Hiptmair-Xu solver. For the saddle-point systems with
non-vanishing wave numbers, we will show that the PCG with a new preconditioner
can apply for the non-singular system when wave numbers are small, while the
methods like preconditioned MINRES may apply for some existing and new
preconditioners when wave numbers are large. The spectral behaviors of the
resulting preconditioned systems for the existing and new preconditioners are
analyzed and compared, and numerical experiments are presented to demonstrate
and compare the efficiencies of these preconditioners.


title:
A realistic quantum capacitance model for quantum Hall edge state based
  Fabry-P\'{e}rot interferometers

abstract:
  In this work, the classical and the quantum capacitances are calculated for a
Fabry-P\'{e}rot interferometer operating in the integer quantized Hall regime.
We first consider a rotationally symmetric electrostatic confinement potential
and obtain the widths and the spatial distribution of the insulating
(incompressible) circular strips using a charge density profile stemming from
self-consistent calculations. Modelling the electrical circuit of capacitors
composed of metallic gates and incompressible/compressible strips, we
investigate the conditions to observe Aharonov-Bohm (quantum mechanical phase
dependent) and Coulomb Blockade (capacitive coupling dependent) effects
reflected in conductance oscillations. In a last step, we solve the
Schr\"odinger and the Poisson equations self-consistently in a numerical manner
taking into account realistic experimental geometries. We find that, describing
the conductance oscillations either by Aharanov-Bohm or Coulomb Blockade
strongly depends on sample properties also other than size, therefore,
determining the origin of these oscillations requires further experimental and
theoretical investigation.


title:
Gradient estimates for some evolution equations on complete smooth
  metric measure spaces

abstract:
  In this paper, we consider the following general evolution equation $$
u_t=\Delta_fu+au\log^\alpha u+bu $$ on smooth metric measure spaces $(M^n, g,
e^{-f}dv)$. We give a local gradient estimate of Souplet-Zhang type for
positive smooth solution of this equation provided that the Bakry-\'{E}mery
curvature bounded from below. When $f$ is constant, we investigate the gereral
evolution on compact Riemannian manifolds with no nconvex boundary satisfying
an "\emph{interior rolling $R$-ball}" condition. We show a gradient estimate of
Hamilton type on such manifolds.


title:
Gradient estimates for some $f$-heat equations driven by Lichnerowicz's
  equation on complete smooth metric measure spaces

abstract:
  Given a complete, smooth metric measure space $(M,g,e^{-f}dv)$ with the
Bakry-\'Emery Ricci curvature bounded from below, various gradient estimates
for solutions of the following general $f$-heat equations $$ u_t=\Delta_f
u+au\log u+bu +Au^p+Bu^{-q} $$ and \[ u_t=\Delta_f u+Ae^{pu}+Be^{-pu}+D \] are
studied. As by-product, we obtain some Liouville-type theorems and Harnack-type
inequalities for positive solutions of several nonlinear equations including
the Schr\"{o}dinger equation, the Yamabe equation, and Lichnerowicz-type
equations as special cases.


title: NMR Observation of Ferro-quadrupole Order in PrTi2Al20

abstract:
  We report the results of 27Al-NMR measurements on a single crystal of
PrTi2Al20. This compound shows a phase transition near 2 K associated with the
quadrupole degree of freedom of Pr ions, for which the ground state of the
crystalline electric field is a nonmagnetic doublet. When a magnetic field is
applied along the <111> direction, the NMR lines split upon entering the
low-temperature phase, indicating the breaking of the three fold rotation
symmetry due to the field-induced magnetic dipole perpendicular to the field.
This provides microscopic evidence for a ferro order of the O20 quadrupole.
Although a first-order transition is expected theoretically, the line splitting
evolves continuously within the experimental resolution.


title: Radial Fourier Multipliers in $\mathbb{R}^3$ and $\mathbb{R}^4$

abstract:
  We prove that for radial Fourier multipliers $m: \mathbb{R}^3\to\mathbb{C}$
supported compactly away from the origin, $T_m$ is restricted strong type (p,p)
if $K=\hat{m}$ is in $L^p(\mathbb{R}^3)$, in the range $1<p<\frac{13}{12}$. We
also prove an $L^p$ characterization for radial Fourier multipliers in four
dimensions; namely, for radial Fourier multipliers $m:
\mathbb{R}^4\to\mathbb{C}$ supported compactly away from the origin, $T_m$ is
bounded on $L^p(\mathbb{R}^4)$ if and only if $K=\hat{m}$ is in
$L^p(\mathbb{R}^4)$, in the range $1<p<\frac{36}{29}$. Our method of proof
relies on a geometric argument that exploits bounds on sizes of multiple
intersections of three-dimensional annuli to control numbers of tangencies
between pairs of annuli in three and four dimensions.


title:
Collision energy dependence of elliptic flow splitting between particles
  and their antiparticles from an extended multiphase transport model

abstract:
  Based on an extended multiphase transport model, which includes mean-field
potentials in both the partonic and hadronic phases, uses the mix-event
coalescence, and respects charge conservation during the hadronic evolution, we
have studied the collision energy dependence of the elliptic flow splitting
between particles and their antiparticles. This extended transport model
reproduces reasonably well the experimental data at lower collision energies
but only describes qualitatively the elliptic flow splitting at higher beam
energies. The present study thus indicates the existence of other mechanisms
for the elliptic flow splitting besides the mean-field potentials and the need
of further improvements of the multiphase transport model.


title:
Large Fizeau's light-dragging effect in a moving electromagnetically
  induced transparent medium

abstract:
  As one of the most influential experiments on the development of modern
macroscopic theory from Newtonian mechanics to Einstein's special theory of
relativity, the phenomenon of light dragging in a moving medium has been
discussed and observed extensively in different types of systems. To have a
significant dragging effect, the long duration of light travelling in the
medium is preferred. Here we demonstrate a light-dragging experiment in an
electromagnetically induced transparent cold atomic ensemble and enhance the
dragging effect by at least three orders of magnitude compared with the
previous experiments. With a large enhancement of the dragging effect, we
realize an atom-based velocimeter that has a sensitivity two orders of
magnitude higher than the velocity width of the atomic medium used. Such a
demonstration could pave the way for motional sensing using the collective
state of atoms in a room temperature vapour cell or solid state material.


title:
Throughput Optimal Listen-Before-Talk for Cellular in Unlicensed
  Spectrum

abstract:
  The effort to extend cellular technologies to unlicensed spectrum has been
gaining high momentum. Listen-before-talk (LBT) is enforced in the regions such
as European Union and Japan to harmonize coexistence of cellular and incumbent
systems in unlicensed spectrum. In this paper, we study throughput optimal LBT
transmission strategy for load based equipment (LBE). We find that the optimal
rule is a pure threshold policy: The LBE should stop listening and transmit
once the channel quality exceeds an optimized threshold. We also reveal the
optimal set of LBT parameters that are compliant with regulatory requirements.
Our results shed light on how the regulatory LBT requirements can affect the
transmission strategies of radio equipment in unlicensed spectrum.


title: Correlation based entanglement criteria for bipartite systems

abstract:
  We introduce a class of inequalities based on low order correlations of
operators to detect entanglement in bipartite systems. The operators may either
be Hermitian or non-Hermitian and are applicable to any physical system or
class of states. Testing the criteria on example systems reveals that they
outperform other common correlation based criteria, such as those by
Duan-Giedke-Cirac-Zoller and Hillery-Zubairy. One unusual feature of the
criteria is that it includes a term involving the average of the density matrix
squared, related to the purity of the system. We discuss how such a term could
be measured in relation to the criteria.


title:
Harnack's Inequality and A Priori Estimates for Fractional Powers of
  Non-symmetric Differential Operators

abstract:
  We obtain a new general extension theorem in Banach spaces for operators
which are not required to be symmetric, and apply it to obtain Harnack
estimates and a priori regularity for solutions of fractional powers of several
second order differential operators. These include weighted elliptic and
subellitptic operators in divergence form (nonnecessarily self-adjoint), and
nondivergence form operators with rough coefficients. We utilize the reflection
extension technique introduced by Caffarelli and Silvestre.


title:
Testing separability and independence of perceptual dimensions with
  general recognition theory: A tutorial and new R package (grtools)

abstract:
  Determining whether perceptual properties are processed independently is an
important goal in perceptual science, and tools to test independence should be
widely available to experimental researchers. The best analytical tools to test
for perceptual independence are provided by General Recognition Theory (GRT), a
multidimensional extension of signal detection theory. Unfortunately, there is
currently a lack of software implementing GRT analyses that is ready-to-use by
experimental psychologists and neuroscientists with little training in
computational modeling. This paper presents grtools, an R package developed
with the explicit aim of providing experimentalists with the ability to perform
full GRT analyses using only a couple of command lines. We describe the
software and provide a practical tutorial on how to perform each of the
analyses available in grtools. We also provide advice to researchers on best
practices for experimental design and interpretation of results.


title:
Interaction of Tannin with Bovine Serum Albumin by Fluorescence
  Spectrometry

abstract:
  Interaction between tannin and bovine serum albumin (BSA) was examined by the
fluorescent quenching. The process of elimination between BSA and tannin was
the one of a stationary state, and the coupling coefficient was one. The
working strength between the tannin and the beef serum was hydrophobic one.


title:
Various notions of best approximation property in spaces of Bochner
  integrable functions

abstract:
  We derive that for a separable proximinal subspace $Y$ of $X$, $Y$ is
strongly proximinal (strongly ball proximinal) if and only if for $1\leq p<
\infty$, $L_p(I,Y)$ is strongly proximinal (strongly ball proximinal) in
$L_p(I,X)$. Case for $p=\infty$ follows from stronger assumption on $Y$ in $X$
(uniform proximinality). It is observed that for a separable proximinal
subspace $Y$ in $X$, $Y$ is ball proximinal in $X$ if and only if $L_p(I,Y)$ is
ball proximinal in $L_p(I,X)$ for $1\leq p\leq\infty$. Our observations also
include the fact that for any (strongly) proximinal subspace $Y$ of $X$, if
every separable subspace of $Y$ is ball (strongly) proximinal in $X$ then
$L_p(I,Y)$ is ball (strongly) proximinal in $L_p(I,X)$ for $1\leq p<\infty$. We
introduce the notion of uniform proximinality of a closed convex set in a
Banach space, which is wrongly defined in \cite{LZ}. Several examples are given
having this property, viz. any $U$-subspace of a Banach space, closed unit ball
$B_X$ of a space with $3.2.I.P$, closed unit ball of any M-ideal of a space
with $3.2.I.P.$ are uniformly proximinal. A new class of examples are given
having this property.


title:
Electron beam test of key elements of the laser-based calibration system
  for the muon $g$ $-$ $2$ experiment

abstract:
  We report the test of many of the key elements of the laser-based calibration
system for muon g - 2 experiment E989 at Fermilab. The test was performed at
the Laboratori Nazionali di Frascati's Beam Test Facility using a 450 MeV
electron beam impinging on a small subset of the final g - 2 lead-fluoride
crystal calorimeter system. The calibration system was configured as planned
for the E989 experiment and uses the same type of laser and most of the final
optical elements. We show results regarding the calorimeter's response
calibration, the maximum equivalent electron energy which can be provided by
the laser and the stability of the calibration system components.


title:
Structural-transition-induced quasi two-dimensional Fermi surface in
  FeSe

abstract:
  We report detailed study of angular-dependent magnetoresistance (AMR) with
tilting angel $\theta$ from $c$-axis ranging from 0$^\circ$ to 360$^\circ$ on a
high-quality FeSe single crystal. A pronounced AMR with twofold symmetry is
observed, which is caused by the quasi two-dimensional (2D) Fermi surface. The
pronounced AMR is observed only in the orthorhombic phase, indicating that the
quasi-2D Fermi surface is induced by the structural transition. Details about
the influence of the multiband effect to the AMR are also discussed. Besides,
the angular response of a possible Dirac-cone-like band structure is
investigated by analyzing the detailed magnetoresistance at different $\theta$.
The obtained characteristic field ($B^*$) can be also roughly scaled in the 2D
approximation, which indicates that the Dirac-cone-like state is also 2D in
nature.


title: Correlated Pair Approach to Composite Boson Scattering Lengths

abstract:
  We derive the scattering length of composite bosons (cobosons) within the
framework of the composite boson many-body formalism that uses correlated-pair
states as a basis, instead of free fermion states. The integral equation
constructed from this physically relevant basis makes transparent the role of
fermion exchange in the coboson-coboson effective scattering. Three potentials
used for Cooper pairs, fermionic-atom dimers, and semiconductor excitons are
considered. While the s-wave scattering length for the BCS-like potential is
just equal to its Born value, the other two are substantially smaller. For
fermionic-atom dimers and semiconductor excitons, our results, calculated
within a restricted correlated-pair basis, are in good agreement with those
obtained from procedures numerically more demanding. We also propose model
coboson-coboson scatterings that are separable and thus easily workable, and
that produce scattering lengths which match quantitatively well with the
numerically-obtained values for all fermion mass ratios. These separable model
scatterings can facilitate future works on many-body effects in coboson gases.


title: On some generalizations of skew-shifts on $\mathbb{T}^2$

abstract:
  In this paper we investigate maps of the two-torus $\mathbb{T}^2$ of the form
$T(x,y)=(x+\omega,g(x)+f(y))$ for Diophantine $\omega\in\mathbb{T}$ and for a
class of maps $f,g:\mathbb{T}\to\mathbb{T}$, where each $g$ is strictly
monotone and of degree 2, and each $f$ is an orientation preserving circle
homeomorphism. For our class of $f$ and $g$ we show that $T$ is minimal and has
exactly two invariant and ergodic Borel probability measures. Moreover, these
measures are supported on two $T$-invariant graphs. One of the graphs is a
Strange Nonchaotic Attractor whose basin of attraction consists of (Lebesgue)
almost all points in $\mathbb{T}^2$. Only a low regularity assumption
(Lipschitz) is needed on the maps $f$ and $g$, and the results are robust with
respect to Lipschitz-small perturbations of $f$ and $g$.


title:
The nonequivariant coherent-constructible correspondence for toric
  stacks

abstract:
  The nonequivariant coherent-costructible correspondence is a
microlocal-geometric interpretation of homological mirror symmetry for toric
varieties conjectured by Fang-Liu-Treumann-Zaslow. We prove a generalization of
this conjecture for a class of toric stacks which includes any toric varieties
and toric orbifolds. Our proof is based on gluing descriptions of
$\infty$-categories of both sides.


title: Specification testing in nonparametric AR-ARCH models

abstract:
  In this paper an autoregressive time series model with conditional
heteroscedasticity is considered, where both conditional mean and conditional
variance function are modeled nonparametrically. A test for the model
assumption of independence of innovations from past time series values is
suggested. The test is based on an weighted $L^2$-distance of empirical
characteristic functions. The asymptotic distribution under the null hypothesis
of independence is derived and consistency against fixed alternatives is shown.
A smooth autoregressive residual bootstrap procedure is suggested and its
performance is shown in a simulation study.


title:
HELIOS-Retrieval: An Open-source, Nested Sampling Atmospheric Retrieval
  Code, Application to the HR 8799 Exoplanets and Inferred Constraints for
  Planet Formation

abstract:
  We present an open-source retrieval code named HELIOS-Retrieval (hereafter
HELIOS-R), designed to obtain chemical abundances and temperature-pressure
profiles from inverting the measured spectra of exoplanetary atmospheres. In
the current implementation, we use an exact solution of the radiative transfer
equation, in the pure absorption limit, in our forward model, which allows us
to analytically integrate over all of the outgoing rays (instead of performing
Gaussian quadrature). Two chemistry models are considered: unconstrained
chemistry (where the mixing ratios are treated as free parameters) and
equilibrium chemistry (enforced via analytical formulae, where only the
elemental abundances are free parameters). The nested sampling algorithm allows
us to formally implement Occam's Razor based on a comparison of the Bayesian
evidence between models. We perform a retrieval analysis on the measured
spectra of the HR 8799b, c, d and e directly imaged exoplanets. Chemical
equilibrium is disfavored by the Bayesian evidence for HR 8799b, c and d. We
find supersolar C/O, C/H and O/H values for the outer HR 8799b and c
exoplanets, while the inner HR 8799d and e exoplanets have substellar C/O,
substellar C/H and superstellar O/H values. If these retrieved properties are
representative of the bulk compositions of the exoplanets, then they are
inconsistent with formation via gravitational instability (without late-time
accretion) and consistent with a core accretion scenario in which late-time
accretion of ices occurred differently for the inner and outer exoplanets. For
HR 8799e, we find that spectroscopy in the K band is crucial for constraining
C/O and C/H. HELIOS-R is publicly available as part of the Exoclimes Simulation
Platform (ESP; www.exoclime.org).


title: A Corrected Parsimony Criterion for Reconstructing Phylogenies

abstract:
  In phylogenetic analysis, for non-molecular data, particularly morphology,
parsimony optimization is the most commonly employed approach. In the past and
present application of the parsimony principle, extra step numbers have been
added across different characters without proper justification. This practice,
however, has caused the impacts of characters to be inflated or deflated
without a valid reason. To resolve this methodological deficiency, here I
present a corrected parsimony criterion for reconstructing phylogenies. In
essence, character rather than step is the most fundamental unit. Accordingly,
the most parsimonious tree should maximize the sum or average of the
phylogenetic signals, quantified by retention index, contributed by each
character. Assigning proper weights to characters is a separate task that
requires information other than the intra-character step number changing range.


title: Law of large numbers for the many-server earliest-deadline-first queue

abstract:
  A many-server queue operating under the earliest deadline first discipline,
where the distributions of service time and deadline are generic, is studied at
the law of large numbers scale. Fluid model equations, formulated in terms of
the many-server transport equation and the recently introduced measure-valued
Skorohod map, are proposed as a means of characterizing the limit. The main
results are the uniqueness of solutions to these equations, and the law of
large numbers scale convergence to the solutions.


title: The High Rate of the Boyajian's Star Anomaly as a Phenomenon

abstract:
  Boyajian's Star (KIC 8462852) undergoes mysterious, irregular eclipses that
aren't yet explained. It also appears to have dimmed over a time of several
years, possibly decades. I show that Kepler's detection of a phenomenon with a
duration of t_anom is only expected if it occurs at a mean rate of >~ 30
Gyr^(-1) (t_anom / 100 yr)^(-1) for each Kepler target and K2 star. If true,
the phenomenon occurs hundreds of times during the lifespan of its host stars.
Obscuration by the interstellar medium remains a plausible explanation, since
it doesn't actually affect the host star. An intervening cloud is consistent
with the lack of an observed submillimeter excess but would be abnormally
dilute.


title:
Comment on: Quantitative study of the $f$ occupation in CeMIn5 and other
  cerium compounds with hard X-rays, [arXiv:1601.03270]

abstract:
  This comment clarifies the mixed definition of the cerium valence in the
article entitled: Quantitative study of the $f$ occupation in CeMIn5 and other
cerium compounds with hard X-rays, published in Journal of Electron
Spectroscopy and Related Phenomena
http://www.sciencedirect.com/science/article/pii/S0368204816300123 and
available on arXiv:1601.03270. Indeed, it is unclear wether electrons belonging
on hybridized f-states are part or not of the valence. When one tries to
simulate the system, an Anderson impurity model only includes valence bands
electrons and localized 4-f states. Therefore hybridized 4-f states are mixed
with the localized ones. From a heavy fermion perspective it however essential
to differentiate hybridized and localized states as only the second are
responsible for strong correlations, such as obtained by susceptibility or
direct comparisons to model systems.


title:
2D surprises at the surface of 3D materials: confined electron systems
  in transition metal oxides

abstract:
  The scope of this article is to review the state-of-the-art in the field of
confined electron systems generated at the bare surfaces of transition metal
oxides (TMOs). This scientific field is a prime example of a domain where
two-dimensional physics and photoemission-based spectroscopic techniques have
together set up the development of the story. The discovery of a high-mobility
two-dimensional electron system (2DES) at interfaces of transition metal oxides
has attracted an immense scientific interest due to new opportunities opened in
the emerging field of oxide electronics. The subsequent paradigm shift from
interfaces to the bare surfaces of TMOs made the confined electron system
accessible to surface-sensitive spectroscopic techniques and this new era is
the focus of the present article. We describe how results by means of
Angle-Resolved Photoemission Spectroscopy (ARPES) establish the presence of
confined electron carriers at the bare surface of SrTiO$_{3}$(100), which
exhibit complex physics phenomena such as orbital ordering, electron-phonon
interactions and spin splitting. The key element behind the 2DES generation is
oxygen vacancies. Moreover, we review the experimental evidence on the
generation of 2DESs on surfaces with different orientation, as well as on
different TMO substrates. The electronic structure of the confined electron
system responds to such changes, thereby providing external means for
engineering its properties. Finally, we identify new directions for future
research by introducing a device-friendly fabrication protocol for the
generation of 2DESs on TMO surfaces.


title:
Prediction of Solar Flares Using Unique Signatures of Magnetic Field
  Images

abstract:
  Prediction of solar flares is an important task in solar physics. The
occurrence of solar flares is highly dependent on the structure and the
topology of solar magnetic fields. A new method for predicting large (M and X
class) flares is presented, which uses machine learning methods applied to the
Zernike moments of magnetograms observed by the Helioseismic and Magnetic
Imager (HMI) onboard the Solar Dynamics Observatory (SDO) for a period of six
years from 2 June 2010 to 1 August 2016. Magnetic field images consisting of
the radial component of the magnetic field are converted to finite sets of
Zernike moments and fed to the Support Vector Machine (SVM) classifier. Zernike
moments have the capability to elicit unique features from any 2-D image, which
may allow more accurate classification. The results indicate whether an
arbitrary active region has the potential to produce at least one large flare.
We show that the majority of large flares can be predicted within 48 hours
before their occurrence, with only 10 false negatives out of 385 flaring active
region magnetograms, and 21 false positives out of 179 non-flaring active
region magnetograms. Our method may provide a useful tool for prediction of
solar flares which can be employed alongside other forecasting methods.


title:
Efficient determination of the Markovian time-evolution towards a
  steady-state of a complex open quantum system

abstract:
  Master equations are commonly used to describe time evolution of open
systems. We introduce a general method for calculating a Markovian solution of
the Nakajima-Zwanzig generalized master equation. We do so for a time dependent
transport of interacting electrons through a complex nano scale system in a
photon cavity. The central system, described by 120 many-body states in a Fock
space, is weakly coupled to the external leads. The very diverse relaxation
times of the open system, reflecting radiative or non-radiative transitions,
require information about the time evolution through many orders of magnitude.
In our approach, the generalized master equation is mapped from a many-body
Fock space of states to a Liouville space of transitions. We show that this
results in a linear equation which is solved exactly through an eigenvalue
analysis, which supplies information on the steady state and the time evolution
of the system.


title:
Pressure-robust analysis of divergence-free and conforming FEM for
  evolutionary incompressible Navier-Stokes flows

abstract:
  This article focusses on the analysis of a conforming finite element method
for the time-dependent incompressible Navier-Stokes equations. For
divergence-free approximations, in a semi-discrete formulation, we prove error
estimates for the velocity that hold independently of both pressure and
Reynolds number. Here, a key aspect is the use of the discrete Stokes
projection for the error splitting. Optionally, edge-stabilisation can be
included in the case of dominant convection. Emphasising the importance of
conservation properties, the theoretical results are complemented with
numerical simulations of vortex dynamics and laminar boundary layer flows.

categories: math.NA math-ph math.MP physics.comp-ph physics.flu-dyn


title: A cheap data assimilation approach for expensive numerical simulations

abstract:
  Using a very cheap Data Assimilation (DA) method, I show an alternative
approach to classical DA for numerical climate models which produce a large
amount of "big data". The problematic features of state-of-the-art high
resolution Regional Climate Models are highlighted. One of the shortcomings is
the sensitivity of such models to the slightly different initial and boundary
conditions which could be corrected by assimilating scattered observational
data. This method might help to reduce the bias of numerical models based on
available observations within the model domain, especially for the
time-averaged observations and the long-term simulations.


title:
Measurement of the $2\nu\beta\beta$ Decay Half-Life and Search for the
  $0\nu\beta\beta$ Decay of $^{116}$Cd with the NEMO-3 Detector

abstract:
  The NEMO-3 experiment measured the half-life of the $2\nu\beta\beta$ decay
and searched for the $0\nu\beta\beta$ decay of $^{116}$Cd. Using $410$ g of
$^{116}$Cd installed in the detector with an exposure of $5.26$ y,
($4968\pm74$) events corresponding to the $2\nu\beta\beta$ decay of $^{116}$Cd
to the ground state of $^{116}$Sn have been observed with a signal to
background ratio of about $12$. The half-life of the $2\nu\beta\beta$ decay has
been measured to be $
T_{1/2}^{2\nu}=[2.74\pm0.04\mbox{(stat.)}\pm0.18\mbox{(syst.)}]\times10^{19}$
y. No events have been observed above the expected background while searching
for $0\nu\beta\beta$ decay. The corresponding limit on the half-life is
determined to be $T_{1/2}^{0\nu} \ge 1.0 \times 10^{23}$ y at the $90$ % C.L.
which corresponds to an upper limit on the effective Majorana neutrino mass of
$\langle m_{\nu} \rangle \le 1.4-2.5$ eV depending on the nuclear matrix
elements considered. Limits on other mechanisms generating $0\nu\beta\beta$
decay such as the exchange of R-parity violating supersymmetric particles,
right-handed currents and majoron emission are also obtained.


title:
Ring-shaped velocity distribution functions in energy-dispersed
  structures formed at the boundaries of a proton stream injected into a
  transverse magnetic field: Test-kinetic results

abstract:
  In this paper, we discuss the formation of ring-shaped and gyro-phase
restricted velocity distribution functions (VDFs) at the edges of a cloud of
protons injected into non-uniform distributions of the electromagnetic field.
The velocity distribution function is reconstructed using the forward
test-kinetic method. We consider two profiles of the electric field: (1) a
non-uniform E-field obtained by solving the Laplace equation consistent with
the conservation of the electric drift and (2) a constant and uniform E-field.
In both cases, the magnetic field is similar to the solutions obtained for
tangential discontinuities. The initial velocity distribution function is
Liouville mapped along numerically integrated trajectories. The numerical
results show the formation of an energy-dispersed structure due to the
energy-dependent displacement of protons towards the edges of the cloud by the
gradient-B drift. Another direct effect of the gradient-B drift is the
formation of ring-shaped velocity distribution functions within the
velocity-dispersed structure. Higher energy particles populate the edges of the
proton beam, while smaller energies are located in the core. Non-gyrotropic
velocity distribution functions form on the front-side and trailing edge of the
cloud; this effect is due to remote sensing of energetic particles with guiding
centers inside the beam. The kinetic features revealed by the test-kinetic
solutions have features similar to in-situ velocity distribution functions
observed by Cluster satellites in the magnetotail, close to the neutral sheet.


title: Self-reflective model predictive control

abstract:
  This paper proposes a novel control scheme, named self-reflective model
predictive control, which takes its own limitations in the presence of process
noise and measurement errors into account. In contrast to existing
output-feedback MPC and persistently exciting MPC controllers, the proposed
self-reflective MPC controller does not only propagate a matrix-valued state
forward in time in order to predict the variance of future state-estimates, but
it also propagates a matrix-valued adjoint state backward in time. This adjoint
state is used by the controller to compute and minimize a second order
approximation of its own expected loss of control performance in the presence
of random process noise and inexact state estimates. The properties of the
proposed controller are illustrated with a small but non-trivial case study.


title: In The Wild Residual Data Research and Privacy

abstract:
  As the world becomes increasingly dependent on technology, researchers in
both industry and academia endeavor to understand how technology is used, the
impact it has on everyday life, the artifact life-cycle and overall
integrations of digital information. In doing so, researchers are increasingly
gathering 'real-world' or 'in-the-wild' residual data, obtained from a variety
of sources, without the explicit consent of the original owners. This data
gathering raises significant concerns regarding privacy, ethics and
legislation, as well as practical considerations concerning investigator
training, data storage, overall security and data disposal. This research
surveys recent studies of residual data gathered in-the-wild and analyzes the
challenges that were confronted. Amalgamating these insights, the research
presents a compendium of practices for addressing the issues that can arise
in-the-wild when conducting residual data research. The practices identified in
this research can be used to critique current projects and assess the
feasibility of proposed future research.


title:
Barrier Option Pricing under the 2-Hypergeometric Stochastic Volatility
  Model

abstract:
  We investigate the pricing of financial options under the 2-hypergeometric
stochastic volatility model. This is an analytically tractable model that
reproduces the volatility smile and skew effects observed in empirical market
data.
  Using a regular perturbation method from asymptotic analysis of partial
differential equations, we derive an explicit and easily computable approximate
formula for the pricing of barrier options under the 2-hypergeometric
stochastic volatility model. The asymptotic convergence of the method is proved
under appropriate regularity conditions, and a multi-stage method for improving
the quality of the approximation is discussed. Numerical examples are also
provided.


title:
Comparative study of forward and backward test-kinetic simulation
  approaches

abstract:
  In this paper we perform a comparative study of the forward and backward
Liouville mapping applied to the modeling of ring-shaped and non-gyrotropic
velocity distribution functions of particles injected in a sheared
electromagnetic field. The test-kinetic method is used to compute the velocity
distribution function in various areas of a proton cloud moving in the vicinity
of a region with a sharp transition of the magnetic field and a non-uniform
electric field. In the forward approach the velocity distribution function is
computed for a two-dimensional spatial bin, while in the backward approach the
distribution function is averaged over a spatial bin with the same size as for
the forward method and using a two-dimensional trapezoidal integration scheme.
It is shown that the two approaches lead to similar results for spatial bins
where the velocity distribution function varies smoothly. On the other hand,
with bins covering regions of configuration space characterized by sharp
spatial gradients of the velocity distribution function, the forward and
backward approaches will generally provide different results.


title: Error Control for Exponential Integration of the Master Equation

abstract:
  Error estimates for the numerical solution of the master equation are
presented. Estimates are based on adjoint methods. We find that a good estimate
can often be computed without spending computational effort on a dual problem.
Estimates are applicable to both settings with time-independent, and
time-dependent propensity functions. The Finite State Projection algorithm
reduces the dimensionality of the problem and time propagation is based on an
Arnoldi exponential integrator, which in the time-dependent setting is combined
with a Magnus method. Local error estimates are devised for the truncation of
both the Magnus expansion and the Krylov subspace in the Arnoldi algorithm. An
issue with existing methods is that error estimates for truncation of the state
space depend on measuring a loss of probability mass in a way that is not
usually compatible with the approximation of the exponential. We suggest an
alternative error estimate that is compatible with a Krylov approximation to
the matrix exponential. Finally, we apply the new error estimates to develop an
adaptive simulation algorithm. Numerical examples demonstrate the benefits of
the approach.


title: Bounds for radii of starlikeness and convexity of some special functions

abstract:
  In this paper we consider some normalized Bessel, Struve and Lommel functions
of the first kind, and by using the Euler-Rayleigh inequalities for the first
positive zeros of combination of special functions we obtain tight lower and
upper bounds for the radii of starlikeness of these functions. By considering
two different normalization of Bessel and Struve functions we give some
inequalities for the radii of convexity of the same functions. On the other
hand, we show that the radii of univalence of some normalized Struve and Lommel
functions are exactly the radii of starlikeness of the same functions. In
addition, by using some ideas of Ismail and Muldoon we present some new lower
and upper bounds for the zeros of derivatives of some normalized Struve and
Lommel functions. The Laguerre-P\'olya class of real entire functions plays an
important role in our study.


title:
An approach to calculation of mass spectra and two-photon decays of
  $c\overline{c}$ mesons in the framework of Bethe-Salpeter Equation

abstract:
  In this work we calculate the mass spectrum of charmonium for $1P,...,3P$
states of $0^{++}$ , $1^{++}$, as well as for $1S,...,4S$ states of $0^{-+}$,
and $1S, ...,5D$ states of $1^{--}$ along with the two-photon decay widths of
ground and first excited state of $0^{++}$ quarkonia for the process,
$O^{++}\rightarrow \gamma\gamma$ in the framework of a QCD motivated
Bethe-Salpeter Equation. In this $4\times 4$ BSE framework, the coupled
Salpeter equations are first shown to decouple for the confining part of
interaction, under heavy-quark approximation, and analyically solved, and later
the one-gluon-exchange interaction is perturbatively incorporated leading to
mass spectral equations for various quarkonia. The analytic forms of wave
functions obtained are used for calculation of two-photon decay widths of
$\chi_{c0}$. Our results are in reasonable agreement with data (where ever
available) and other models.


title: Model-Free Closed-Loop Stability Analysis: A Linear Functional Approach

abstract:
  Performing a stability analysis during the design of any electronic circuit
is critical to guarantee its correct operation. A closed-loop stability
analysis can be performed by analysing the impedance presented by the circuit
at a well-chosen node without internal access to the simulator. If any of the
poles of this impedance lie in the complex right half-plane, the circuit is
unstable. The classic way to detect unstable poles is to fit a rational model
on the impedance.
  In this paper, a projection-based method is proposed which splits the
impedance into a stable and an unstable part by projecting on an orthogonal
basis of stable and unstable functions. When the unstable part lies
significantly above the interpolation error of the method, the circuit is
considered unstable. Working with a projection provides one, at small cost,
with a first appraisal of the unstable part of the system.
  Both small-signal and large-signal stability analysis can be performed with
this projection-based method. In the small-signal case, a low-order rational
approximation can be fitted on the unstable part to find the location of the
unstable poles.


title: Measuring Structural Parameters Through Stacking Galaxy Images

abstract:
  It remains challenging to detect the low surface brightness structures of
faint high-z galaxies, which is key to understanding the structural evolution
of galaxies. The technique of image stacking allows us to measure the averaged
light profile beneath the detection limit and probe the extended structure of a
group of galaxies. We carry out simulations to examine the recovery of the
averaged surface brightness profile through stacking model HST/ACS images of a
set of galaxies as functions of Sersic index (n), effective radius (Re) and
axis ratio (AR). The Sersic profile best fitting the radial profile of the
stacked image is taken as the recovered profile, in comparison with the
intrinsic mean profile of the model galaxies. Our results show that, in
general, the structural parameters of the mean profile can be properly
determined through stacking, although systematic biases need to be corrected
when spreads of Re and AR are counted. We find that Sersic index is slightly
overestimated and Re is underestimated at AR < 0.5 as the stacked image appears
to be more compact due to the presence of inclined galaxies; the spread of Re
biases the stacked profile to have a higher Sersic index. We stress that the
measurements of structural parameters through stacking should take these biases
into account. We estimate the biases in the recovered structural parameters
from stacks of galaxies when the samples have distributions of Re, AR and n
seen in local galaxies.


title:
Uniqueness of scatterer in inverse acoustic obstacle scattering with a
  single incident plane wave

abstract:
  In this paper, we give a positive answer to a challenging open problem for
recovering unknown obstacle (which is usually referred to as a scatterer) by
acoustic wave probe associated to the Helmholtz equation. We show that the
acoustic scattering amplitude $A(\beta, {\alpha}_0, k_0)$, known for all
${\beta}\in {\mathbb S}^2$, where ${\mathbb {S}}^2$ is the unit sphere in
${\mathbb{R}}^3$, ${{\alpha}}_0\in {\mathbb{S}}^2$ is fixed, $k_0>0$ is fixed,
determines the obstacle $D$ and the boundary condition on $\partial D$ uniquely
(The boundary condition on $\partial D$ is either the Dirichlet, or Neumann, or
the impedance one).


title: Elastohydrodynamic Synchronization of Adjacent Beating Flagella

abstract:
  It is now well established that nearby beating pairs of eukaryotic flagella
or cilia typically synchronize in phase. A substantial body of evidence
supports the hypothesis that hydrodynamic coupling between the active
filaments, combined with waveform compliance, provides a robust mechanism for
synchrony. This elastohydrodynamic mechanism has been incorporated into
`bead-spring' models in which flagella are represented by microspheres tethered
by radial springs as internal forces drive them about orbits. While these
low-dimensional models reproduce the phenomenon of synchrony, their parameters
are not readily relatable to those of flagella. More realistic models which
reflect the elasticity of the axonemes and active force generation take the
form of fourth-order nonlinear PDEs. While computational studies have shown
synchrony, the effects of hydrodynamic coupling between nearby filaments
governed by such models have been theoretically examined only in the regime of
interflagellar distances $d$ large compared to flagellar length $L$. Yet, in
many biological situations $d/L \ll 1$. Here, we first present an asymptotic
analysis of the hydrodynamic coupling between two filaments in the regime $d/L
\ll 1$, and find that the form of the coupling is independent of the details of
the internal forces that govern the motion of the filaments. The analysis is
like the localized induction approximation for vortex filament motion, extended
to the case of mutual induction. To understand how the coupling mechanism leads
to synchrony of extended objects, we introduce a heuristic model of flagellar
beating, a single fourth-order nonlinear PDE whose form is derived from
symmetry considerations, the physics of elasticity, and the overdamped nature
of the dynamics. Analytical and numerical studies of this model illustrate how
synchrony between two filaments is achieved through the asymptotic coupling.


title: Quantum frequency conversion between infrared and ultraviolet

abstract:
  We report on the implementation of quantum frequency conversion (QFC) between
infrared (IR) and ultraviolet (UV) wavelengths by using single-stage
upconversion in a periodically poled KTP waveguide. Due to the monolithic
waveguide design, we manage to transfer a telecommunication band input photon
to the wavelength of the ionic dipole transition of Yb${}^{+}$ at 369.5 nm. The
external (internal) conversion efficiency is around 5\% (10\%). The high energy
pump used in this converter introduces a spontaneous parametric downconversion
(SPDC) process, which is a cause for noise in the UV mode. Using this SPDC
process, we show that the converter preserves non-classical correlations in the
upconversion process, rendering this miniaturized interface a source for
quantum states of light in the UV.


title:
Determining pitch-angle diffusion coefficients from test particle
  simulations

abstract:
  Transport and acceleration of charged particles in turbulent media is a topic
of great interest in space physics and interstellar astrophysics. These
processes are dominated by the scattering of particles off magnetic
irregularities. The scattering process itself is usually described by
small-angle scattering with the pitch-angle coefficient $D_{\mu\mu}$ playing a
major role. Since the diffusion coefficient $D_{\mu\mu}$ can be determined
analytically only for the approximation of quasi-linear theory, the
determination of this coefficient from numerical simulations has, therefore,
become more important. So far these simulations yield particle tracks for
small-scale scattering, which can then be interpreted using the running
diffusion coefficients. This method has a limited range of validity. This paper
presents two new methods that allow for the calculation of the pitch-angle
diffusion coefficient from numerical simulations. These methods no longer
analyse particle trajectories, but the change of particle distribution
functions. It is shown that they provide better resolved results and allow for
the analysis of strong turbulence. The application of these methods to Monte
Carlo simulations of particle scattering and hybrid MHD-particle simulations is
presented. Both analysis methods are able to recover the diffusion coefficients
used as input for the Monte Carlo simulations and provide better results in MHD
simulations especially for stronger turbulence.


title: Braids, orderings and minimal volume cusped hyperbolic 3-manifolds

abstract:
  It is well-known that there is a faithful representation of braid groups on
automorphism groups of free groups, and it is also well-known that free groups
are bi-orderable. We investigate which n-strand braids give rise to
automorphisms which preserve some bi-ordering of the free group rank n. As a
consequence of our work we find that of the two minimal volume hyperbolic
2-cusped orientable 3-manifolds, one has bi-orderable fundamental group whereas
the other does not. We prove a similar result for the 1-cusped case, and have
further results for more cusps. In addition, we study pseudo-Anosov braids and
find that typically those with minimal dilatation are not order-preserving.


title: Solitons of a vector model on the honeycomb lattice

abstract:
  We study a simple nonlinear vector model defined on the honeycomb lattice. We
propose a bilinearization scheme for the field equations and demonstrate that
the resulting system is closely related to the well-studied integrable models,
such as the Hirota bilinear difference equation and the Ablowitz-Ladik system.
This result is used to derive the N-soliton solutions.


title:
Evidence of AGB pollution in Galactic globular clusters from the Mg-Al
  anticorrelations observed by the APOGEE survey

abstract:
  We study the formation of multiple populations in globular clusters (GC),
under the hypothesis that stars in the second generation formed from the winds
of intermediate-mass stars, ejected during the asymptotic giant branch (AGB)
phase, possibly diluted with pristine gas, sharing the same chemical
composition of first-generation stars. To this aim, we use the recent APOGEE
data, which provide the surface chemistry of a large sample of giant stars,
belonging to clusters that span a wide metallicity range. The APOGEE data set
is particularly suitable to discriminate among the various pollution scenarios
proposed so far, as it provides the surface abundances of Mg and Al, the two
elements involved in a nuclear channel extremely sensitive to the temperature,
hence to the metallicity of the polluters. The present analysis shows a
remarkable agreement between the observations and the theoretical yields from
massive AGB stars. In particular, the observed extension of the depletion of Mg
and O and the increase in Al is well reproduced by the models and the trend
with the metallicity is also fully accounted for. This study further supports
the idea that AGB stars were the key players in the pollution of the
intra-cluster medium, from which additional generations of stars formed in GC.


title: Partonic structure of proton in the resonance region

abstract:
  We separate the contributions of parton distributions from higher twist
corrections to the deeply inelastic lepton-proton scattering in the resonance
region using the Jefferson Lab data at low $Q^2$. The study indicates that the
concept of the valence quarks and their distributions are indispensable even at
$Q^2<1GeV^2$. The quark-hadron duality is also discussed.


title:
A Flat and Scalable Data Center Network Topology Based on De Bruijn
  Graphs

abstract:
  Due to the requirement of hosting tens of thousands of hosts in today's data
centers, data center networks strive for scalability and high throughput on the
one hand. On the other hand, the cost for networking hardware should be
minimized. Consequently, the number and complexity (e.g. TCAM size) of switches
has to be minimized. These requirements led to network topologies like Clos and
Leaf-Spine networks only requiring a shallow hierarchy of switches---two levels
for Leaf-Spine networks. The drawback of these topologies is that switches at
higher levels like Spine switches need a high port density and, thus, are
expensive and limit the scalability of the network.
  In this paper, we propose a data center network topology based on De Bruijn
graphs completely avoiding a switch hierarchy and implementing a flat network
topology of top-of-rack switches instead. This topology guarantees logarithmic
(short) path length. We show that the required routing logic can be implemented
by standard prefix matching operations in hardware (TCAM) allowing for using
commodity switches without any modification. Moreover, forwarding requires only
a very small number of forwarding table entries, saving costly and
energy-intensive TCAM.


title: Toward a new instances of NELL

abstract:
  We are developing the method to start new instances of NELL in various
languages and develop then NELL multilingualism. We base our method on our
experience on NELL Portuguese and NELL French. This reports explain our method
and develops some research perspectives.


title: Strongly interacting matter from holographic QCD model

abstract:
  We introduce the 5-dimension dynamical holographic QCD model, which is
constructed in the graviton-dilaton-scalar framework with the dilaton
background field $\Phi$ and the scalar field $X$ responsible for the
gluodynamics and chiral dynamics, respectively. We review our results on the
hadron spectra including the glueball and light meson spectra, QCD phase
transitions and transport properties in the framework of the dynamical
holographic QCD model.


title: Quantum state transfer with ultracold atoms in optical lattices

abstract:
  Ultracold atoms can be used to perform quantum simulations of a variety of
condensed matter systems, including spin systems. These progresses point to the
implementation of the manipulation of quantum states and to observe and exploit
the effect of quantum correlations. A natural direction along this line is
provided by the possibility to perform quantum state transfer (QST). After
presenting a brief discussion of the simulation of quantum spin chains with
ultracold gases and reminding the basic facts of QST, we discuss how to
potentially use the tools of present-day ultracold technology to implement the
QST between two regions of the atomic system (the sender and the receiver). The
fidelity and the typical timescale of the QST are discussed, together with
possible limitations and applications of the presented results.


title:
Runaway-electron formation and electron slide-away in an ITER
  post-disruption scenario

abstract:
  Mitigation of runaway electrons is one of the outstanding issues for the
reliable operation of ITER and other large tokamaks, and accurate estimates for
the expected runaway-electron energies and current are needed. Previously,
linearized tools (which assume the runaway population to be small) have been
used to study the runaway dynamics, but these tools are not valid in the cases
of most interest, i.e. when the runaway population becomes substantial. We
study runaway-electron formation in a post-disruption ITER plasma using the
newly developed non-linear code NORSE, and describe a feedback mechanism by
which a transition to electron slide-away can be induced at field strengths
significantly lower than previously expected. If the electric field is actively
imposed using the control system, the entire electron population is quickly
converted to runaways in the scenario considered. We find the time until the
feedback mechanism sets in to be highly dependent on the details of the
mechanisms removing heat from the thermal electron population.


title:
Searches for the FCNC couplings from top-Higgs associated production
  signal with $h\to \gamma\gamma$ at the LHC

abstract:
  In this paper, we study the observability of the top-Higgs flavor changing
neutral current (FCNC) $tqh$ coupling through the process $pp\to qg\to t(\to
\ell^{+}b\nu)h(\to \gamma\gamma)$ at the Large Hadron Collider~(LHC), where
$\ell=e, \mu$. Our numerical results show that, in some parameter regions, the
LHC may observe the above signals at the $5\sigma$ level. Otherwise, the
branching ratios $Br(t\to uh)$ and $Br(t\to ch)$ can be respectively probed to
$0.036\%$ and $0.13\%$ at $3\sigma$ level at 14 TeV LHC with the high
integrated luminosity of 3000 fb$^{-1}$. On the other hand, studying the charge
ratio for the lepton in top quark decay can be not only used to discriminate
between signal and backgrounds, but also used to discriminate between $tuh$ and
$tch$ couplings, for which anomalous single top production comes from the up
initiated channel and charm initiated channel.


title: Supersymmetry in Open Superstring Field Theory

abstract:
  We realize the 16 unbroken supersymmetries on a BPS D-brane as invariances of
the action of the corresponding open superstring field theory. We work in the
small Hilbert space approach, where a symmetry of the action translates into a
symmetry of the associated cyclic $A_\infty$ structure. We compute the
supersymmetry algebra, being careful to disentangle the components which
produce a translation, a gauge transformation, and a symmetry transformation
which vanishes on-shell. Via the minimal model theorem, we illustrate how
supersymmetry of the action implies supersymmetry of the tree level open string
scattering amplitudes.


title:
Resonance poles and threshold energies for hadron physical problems by a
  model-independent universal algorithm

abstract:
  We show how complex resonance poles and threshold energies for systems in
hadron physics can be accurately obtained by using a method based on the
Pad\'{e}-approximant which was recently developed for the calculation of
resonance poles for atomic and molecular auto-ionization systems. The main
advantage of this method is the ability to calculate the resonance poles and
threshold energies from \emph{real} spectral data. In order to demonstrate the
capabilities of this method we apply it here to an analytical model as well as
to experimental data for the squared modulus of the vector pion form factor,
the S0 partial wave amplitude for $\pi\pi$ scattering and the cross section
ratio $R(s)$ for $e^+e^-$ collisions. The extracted values for the resonance
poles of the $\rho(770)$ and the $f_0(500)$ or $\sigma$ meson are in very good
agreement with the literature. When the data are noisy the prediction of decay
thresholds proves to be less accurate but feasible.


title: A quantum spectrum analyzer enhanced by a nuclear spin memory

abstract:
  We realize a two-qubit sensor designed for achieving high spectral resolution
in quantum sensing experiments. Our sensor consists of an active "sensing
qubit" and a long-lived "memory qubit", implemented by the electronic and the
nitrogen-15 nuclear spins of a nitrogen-vacancy center in diamond,
respectively. Using state storage times of up to 45 ms, we demonstrate
spectroscopy of external ac signals with a line width of 19 Hz (~2.9 ppm) and
of carbon-13 nuclear magnetic resonance (NMR) signals with a line width of 190
Hz (~ 74 ppm). This represents an up to 100-fold improvement in spectral
resolution compared to measurements without nuclear memory.


title:
Fast sausage modes in magnetic tubes with continuous transverse
  profiles: effects of a finite plasma beta

abstract:
  While standing fast sausage modes in flare loops are often invoked to
interpret quasi-periodic pulsations (QPPs) in solar flares, it is unclear as to
how they are influenced by the combined effects of a continuous transverse
structuring and a finite internal plasma beta ($\beta_{\rm i}$). We derive a
generic dispersion relation (DR) governing linear sausage waves in straight
magnetic tubes for which plasma pressure is not negligible and the density and
temperature inhomogeneities of essentially arbitrary form take place in a layer
of arbitrary width. Focusing on fast modes, we find that $\beta_{\rm i}$ only
weakly influences $k_{\rm c}$, the critical longitudinal wavenumber separating
the leaky from trapped modes. Likewise, for both trapped and leaky modes, the
periods $P$ in units of the transverse fast time depend only weakly on
$\beta_{\rm i}$, which is compatible with the fact that the effective
wavevectors of fast sausage modes are largely perpendicular to the background
magnetic field. However, a weak $\beta_{\rm i}$ dependence of the damping times
$\tau$ is seen only when the length-to-radius ratio $L/R$ is $\sim 50\%$ larger
than some critical value $\pi/(k_{\rm c} R)$, which itself rather sensitively
depends on the density contrast, profile steepness as well as on how the
transverse structuring is described. In the context of QPPs, we conclude that
the much simpler zero-beta theory can be employed for trapped modes, as long as
one sees the deduced internal Alfv\'en speed as actually being the fast speed.
In contrast, effects due to a finite beta in flare loops should be considered
when leaky modes are exploited.


title:
Finiteness of gibbs measures on noncompact manifolds with pinched
  negative curvature

abstract:
  We characterize the finiteness of Gibbs measures for geodesic flows on
negatively curved manifolds by several criteria, analogous to those proposed by
Sarig for symbolic dynamical systems over an infinite alphabet. As an
application, we recover Dal'bo-Otal-Peign{\'e} criterion of finiteness for the
Bowen-Margulis measure on geometrically finite hyperbolic manifolds, as well as
Peign{\'e}' examples of gemetrically infinite manifolds having a finite
Bowen-Margulis measure. These criteria should be useful in the future to find
more examples with finite Gibbs measures.


title: GMM-Free Flat Start Sequence-Discriminative DNN Training

abstract:
  Recently, attempts have been made to remove Gaussian mixture models (GMM)
from the training process of deep neural network-based hidden Markov models
(HMM/DNN). For the GMM-free training of a HMM/DNN hybrid we have to solve two
problems, namely the initial alignment of the frame-level state labels and the
creation of context-dependent states. Although flat-start training via
iteratively realigning and retraining the DNN using a frame-level error
function is viable, it is quite cumbersome. Here, we propose to use a
sequence-discriminative training criterion for flat start. While
sequence-discriminative training is routinely applied only in the final phase
of model training, we show that with proper caution it is also suitable for
getting an alignment of context-independent DNN models. For the construction of
tied states we apply a recently proposed KL-divergence-based state clustering
method, hence our whole training process is GMM-free. In the experimental
evaluation we found that the sequence-discriminative flat start training method
is not only significantly faster than the straightforward approach of iterative
retraining and realignment, but the word error rates attained are slightly
better as well.


title: Catastrophic thinning of dielectric elastomers

abstract:
  We provide a clear energetic insight into the catastrophic nature of the
so-called creasing and pull-in instabilities in soft electro-active elastomers.
These phenomena are ubiquitous for thin electro-elastic plates and are a major
obstacle to the development of giant actuators; yet they are not completely
understood nor modelled accurately. Here, in complete agreement with
experiments, we give a simple formula to predict the voltage thresholds for
these instability patterns and model their shape, and show that equilibrium is
impossible beyond their onset. Our analysis is fully analytical, does not
require finite element simulations, and can be extended to include pre-stretch
and to encompass any material behaviour.


title: CTA in the Context of Searches for Particle Dark Matter - a glimpse

abstract:
  In this contribution, CTAs potential role in detection of particle dark
matter in the context of other detection approaches is briefly discussed for an
audience of gamma-ray astronomers. In particular searches for new particles at
the large hadron collider and detection of dark matter particles in deep
underground detectors are considered. We will focus on Weakly Interacting
Massive Particles (WIMP). Approaches will be compared in terms of (a)
robustness of sensitivity predictions, (b) timeline and (c) reach. The estimate
of the reach will be model-dependent. Given our ignorance about the nature of
dark matter, and the complementarity of detection techniques even within a
given framework (e.g. Supersymmetry), the trivial conclusion is that we might
need all approaches and the most sensitive experiments. Our discussion will be
somewhat more restrictive in order to be able to be more concrete. With the
caveat of incompleteness, under the assumption that the WIMP paradigm describes
nature, CTA is more likely to discover multi-TeV WIMP dark matter, whereas for
lower masses direct detection and LHC has significantly better prospects. We
will illustrate this conclusion with examples from foremost Supersymmetry, but
mention effective field theory or simplified models. We will comment on a few
models predicting high mass WIMPs, in particular 1 TeV higgsino and wino WIMPs,
as well as Minimal Dark Matter and point out the relevance of updated
measurements of the anomalous magnetic moment of the muon for CTAs role in
searches for Supersymmetry.


title: Epidemics of Liquidity Shortages in Interbank Markets

abstract:
  Financial contagion from liquidity shocks has being recently ascribed as a
prominent driver of systemic risk in interbank lending markets. Building on
standard compartment models used in epidemics, in this work we develop an EDB
(Exposed-Distressed-Bankrupted) model for the dynamics of liquidity shocks
reverberation between banks, and validate it on electronic market for interbank
deposits data. We show that the interbank network was highly susceptible to
liquidity contagion at the beginning of the 2007/2008 global financial crisis,
and that the subsequent micro-prudential and liquidity hoarding policies
adopted by banks increased the network resilience to systemic risk---yet with
the undesired side effect of drying out liquidity from the market. We finally
show that the individual riskiness of a bank is better captured by its network
centrality than by its participation to the market, along with the currently
debated concept of "too interconnected to fail".


title:
Channel Training for Analog FDD Repeaters: Optimal Estimators and
  Cram\'er-Rao Bounds

abstract:
  For frequency division duplex channels, a simple pilot loop-back procedure
has been proposed that allows the estimation of the UL & DL channels at an
antenna array without relying on any digital signal processing at the terminal
side. For this scheme, we derive the maximum likelihood (ML) estimators for the
UL & DL channel subspaces, formulate the corresponding Cram\'er-Rao bounds and
show the asymptotic efficiency of both (SVD-based) estimators by means of Monte
Carlo simulations. In addition, we illustrate how to compute the underlying
(rank-1) SVD with quadratic time complexity by employing the power iteration
method. To enable power control for the data transmission, knowledge of the
channel gains is needed. Assuming that the UL & DL channels have on average the
same gain, we formulate the ML estimator for the channel norm, and illustrate
its robustness against strong noise by means of simulations.


title:
Propagation of chaos for aggregation equations with no-flux boundary
  conditions and sharp sensing zones

abstract:
  We consider a $N$-particle interacting particle system with the vision
geometrical constraints and reflected noises, proposed as a model for
collective behavior of individuals. We rigorously derive a continuity-type of
mean-field equation with discontinuous kernels and the normal reflecting
boundary conditions from that stochastic particle system as the number of
particles $N$ goes to infinity. More precisely, we provide a quantitative
estimate of the convergence in law of the empirical measure associated to the
particle system to a probability measure which possesses a density which is a
weak solution to the continuity equation. This extends previous results on an
interacting particle system with bounded and Lipschitz continuous drift terms
and normal reflecting boundary conditions by Sznitman[J. Funct. Anal., 56,
(1984), 311--336] to that one with discontinuous kernels.


title: Model Reduction for Systems with Inhomogeneous Initial Conditions

abstract:
  We consider the model reduction problem for linear time-invariant dynamical
systems having nonzero (but otherwise indeterminate) initial conditions.
Building upon the observation that the full system response is decomposable as
a superposition of the response map for an unforced system having nontrivial
initial conditions and the response map for a forced system having null initial
conditions, we develop a new approach that involves reducing these component
responses independently and then combining the reduced responses into an
aggregate reduced system response. This approach allows greater flexibility and
offers better approximation properties than other comparable methods.


title: Error Asymmetry in Causal and Anticausal Regression

abstract:
  It is generally difficult to make any statements about the expected
prediction error in an univariate setting without further knowledge about how
the data were generated. Recent work showed that knowledge about the real
underlying causal structure of a data generation process has implications for
various machine learning settings. Assuming an additive noise and an
independence between data generating mechanism and its input, we draw a novel
connection between the intrinsic causal relationship of two variables and the
expected prediction error. We formulate the theorem that the expected error of
the true data generating function as prediction model is generally smaller when
the effect is predicted from its cause and, on the contrary, greater when the
cause is predicted from its effect. The theorem implies an asymmetry in the
error depending on the prediction direction. This is further corroborated with
empirical evaluations in artificial and real-world data sets.