title:
KSR: A Semantic Representation of Knowledge Graph within a Novel
  Unsupervised Paradigm

abstract:
  Knowledge representation is a long-history topic in AI, which is very
important. A variety of models have been proposed for knowledge graph
embedding, which projects symbolic entities and relations into continuous
vector space. However, most related methods merely focus on the data-fitting of
knowledge graph, and ignore the interpretable semantic expression. Thus,
traditional embedding methods are not friendly for applications that require
semantic analysis, such as question answering and entity retrieval. To this
end, this paper proposes a semantic representation method for knowledge graph
\textbf{(KSR)}, which imposes a two-level hierarchical generative process that
globally extracts many aspects and then locally assigns a specific category in
each aspect for every triple. Since both aspects and categories are
semantics-relevant, the collection of categories in each aspect is treated as
the semantic representation of this triple. Extensive experiments show that our
model outperforms other state-of-the-art baselines substantially.


title: Clique Coverings and Claw-free Graphs

abstract:
  Let $\cal C$ be a clique covering for $E(G)$ and let $v$ be a vertex of $G$.
The valency of vertex $v$ (with respect to $\cal C$), denoted by $val_{\cal
C}(v)$, is the number of cliques in $\cal C$ containing $v$. The local clique
cover number of $G$, denoted by $lcc(G)$, is defined as the smallest integer
$k$, for which there exists a clique covering for $E(G)$ such that $val_{\cal
C}(v)$ is at most $k$, for every vertex $v\in V(G)$. In this paper, among other
results, we prove that if $G$ is a claw-free graph, then $lcc(G)+\chi(G)\leq
n+1$.


title:
The role of the C2 gas in the emergence of C60 from the condensing
  carbon vapour

abstract:
  A model has been developed that illustrates the emergence of C60 from the
condensing carbon vapor. It is shown to depend upon the decreasing heats of
formation for larger cages, exponentially increasing number of isomers for
fullerenes that are larger than C60, large cages buckling induced by the
pentagon-related protrusions that initiate fragmentation, the structural
instability induces fragmentation that shrinks large cages and an evolving gas
of C2 that is crucial to the whole process. The model describes a mechanism for
the provision and presence of plenty of C2 during the formation and
fragmentation processes. The bottom-up formations of large cages followed by
the top-down cage shrinkage are shown to be stable, dynamical processes that
lead to the C60 dominated fullerene ensemble.


title:
Duality between chiral symmetry breaking and charged pion condensation
  at large $N_c$: Consideration of an NJL$_2$ model with baryon-, isospin- and
  chiral isospin chemical potentials

abstract:
  In this paper we investigate the phase structure of a (1+1)-dimensional
schematic quark model with four-quark interaction and in the presence of baryon
($\mu_B$), isospin ($\mu_I$) and chiral isospin ($\mu_{I5}$) chemical
potentials. It is established that in the large-$N_c$ limit ($N_c$ is the
number of colored quarks) there exists a duality correspondence between the
chiral symmetry breaking phase and the charged pion condensation (PC) one. The
role and influence of this property on the phase structure of the model are
studied. Moreover, it is shown that the chemical potential $\mu_{I5}$ promotes
the appearance of the charged PC phase with nonzero baryon density.


title:
A minimization problem with free boundary related to a cooperative
  system

abstract:
  We study the minimum problem for the functional $\int_{\Omega}\bigl( \vert
\nabla \mathbf{u} \vert^{2} + Q^{2}\chi_{\{\vert \mathbf{u}\vert>0\}} \bigr)dx$
with the constraint $u_i\geq 0$ for $i=1,\cdots,m$ where
$\Omega\subset\mathbb{R}^{n}$ is a bounded domain and
$\mathbf{u}=(u_1,\cdots,u_m)\in H^{1}(\Omega;\mathbb{R}^{m})$.
  Using an array of technical tools, from geometric analysis for the free
boundaries, we reduce the problem to its scalar counterpart and hence conclude
similar results as that of scalar problem. This can also be seen as the most
novel part of the paper, that possibly can lead to further developments of free
boundary regularity for systems.


title:
A Boundary Tilting Persepective on the Phenomenon of Adversarial
  Examples

abstract:
  Deep neural networks have been shown to suffer from a surprising weakness:
their classification outputs can be changed by small, non-random perturbations
of their inputs. This adversarial example phenomenon has been explained as
originating from deep networks being "too linear" (Goodfellow et al., 2014). We
show here that the linear explanation of adversarial examples presents a number
of limitations: the formal argument is not convincing, linear classifiers do
not always suffer from the phenomenon, and when they do their adversarial
examples are different from the ones affecting deep networks.
  We propose a new perspective on the phenomenon. We argue that adversarial
examples exist when the classification boundary lies close to the submanifold
of sampled data, and present a mathematical analysis of this new perspective in
the linear case. We define the notion of adversarial strength and show that it
can be reduced to the deviation angle between the classifier considered and the
nearest centroid classifier. Then, we show that the adversarial strength can be
made arbitrarily high independently of the classification performance due to a
mechanism that we call boundary tilting. This result leads us to defining a new
taxonomy of adversarial examples. Finally, we show that the adversarial
strength observed in practice is directly dependent on the level of
regularisation used and the strongest adversarial examples, symptomatic of
overfitting, can be avoided by using a proper level of regularisation.


title: On doubly nonlocal fractional elliptic equations

abstract:
  This work is devoted to the study of the existence of solutions to nonlocal
equations involving the fractional Laplacian. These equations have a
variational structure and we find a nontrivial solution for them using the
Mountain Pass Theorem. To make the nonlinear methods work, some careful
analysis of the fractional spaces involved is necessary. In addition, we
require rather general assumptions on the local operator. As far as we know,
this result is new and represent a fractional version of a classical theorem
obtained working with Laplacian equations.


title:
Existence and localization of solutions for nonlocal fractional
  equations

abstract:
  This work is devoted to the study of the existence of at least one weak
solution to nonlocal equations involving a general integro-differential
operator of fractional type. As a special case, we derive an existence theorem
for the fractional Laplacian, finding a nontrivial weak solution of the
equation \begin{eqnarray*} \begin{cases} (-\Delta)^s u=h(x)f(u) & {\mbox{ in }}
\Omega\\ u=0 & {\mbox{ in }} \mathbb{R}^n\setminus \Omega, \end{cases}
\end{eqnarray*} where $h\in L^{\infty}_+(\Omega)\setminus\{0\}$ and
$f:\mathbb{R}\rightarrow\mathbb{R}$ is a suitable continuous function. These
problems have a variational structure and we find a nontrivial weak solution
for them by exploiting a recent local minimum result for smooth functionals
defined on a reflexive Banach space. To make the nonlinear methods work, some
careful analysis of the fractional spaces involved is necessary.


title: Algebraic systems with Lipschitz perturbations

abstract:
  By using variational methods, the existence of infinitely many solutions for
a nonlinear algebraic system with a parameter is established in presence of a
perturbed Lipschitz term. Our goal was achieved requiring an appropriate
behavior of the nonlinear term $f$, either at zero or at infinity, without
symmetry conditions.


title:
Foreign Exchange Market Performance: Evidence from Bivariate Time Series
  Approach

abstract:
  There are many studies dealing with the analysis of similarity among
currencies in foreign exchange market by using network analysis approach. In
those studies, each currency is represented by a univariate time series of
exchange rate return. This is the standard practice to analyze the underlying
information in the foreign exchange market. In this paper, Escoufier's RV
coefficient is applied to measure the similarity among currencies where each of
them is represented by bivariate time series. Based on that coefficient, we
analyze the topological structure of the currencies. An example of FOREX
analysis will be presented and discussed to illustrate the advantages of RV
coefficient.


title:
Global stability analysis of axisymmetric boundary layer over a circular
  cone

abstract:
  This paper presents the linear Global stability analysis of the
incompressible axisymmetric boundary layer on a circular cone. The base flow is
considered parallel to the axis of cone at the inlet. The angle of attack is
zero and hence the base flow is axisymmetric. The favorable pressure gradient
develops in the stream-wise direction due to cone angle. The Reynolds number is
calculated based on the cone radius (a) at the inlet and free-stream velocity
($U_{\infty}$). The base flow velocity profile is fully non-parallel and
non-similar. Linearized Navier-Stokes equations (LNS) are derived for the
disturbance flow quantities in the spherical coordinates. The LNS are
discretized using Chebyshev spectral collocation method. The discretized LNS
along with the homogeneous boundary conditions forms a general eigenvalues
problem. Arnoldi's iterative algorithm is used for the numerical solution of
the general eigenvalues problem. The Global temporal modes are computed for the
range of Reynolds number from 174 to 1046, semi-cone angles $2^o$, $4^o$, $6^o$
and azimuthal wave numbers from 0 to 5. It is found that the Global modes are
more stable at higher semi-cone angle $\alpha$, due to the development of
favorable pressure gradient. The effect of transverse curvature is reduced at
higher semi-cone angles ($\alpha$). The spatial structure of the eigenmodes
show that the flow is convectively unstable. The spatial growth rate ($A_x$)
increases with the increase in semi-cone angle ($\alpha$) from $2^o$ to $6^o$.
Thus, the effect of increase in semi-cone angle ($\alpha$) is to reduces the
temporal growth rate ($\omega_i$) and to increases the spatial growth rate
($A_x$) of the Global modes at a given Reynolds number.


title: Existence and properties of the Navier-Stokes equations

abstract:
  A proof of existence, uniqueness and smoothness of the Navier-Stokes
equations is an actual problem, which solution is important for different
branches of science. The subject of this study is obtaining the smooth and
unique solutions of the three-dimension Stokes-Navier equations for the initial
and boundary value problem. The analysis shows that there exist no viscous
solutions of the Navier-Stokes equations in three dimensions. The reason is the
insufficient capability of the divergence-free velocity field. It is necessary
to modify the Navier-Stokes equations for obtaining the desirable solutions.
The modified equations describe a three-dimension flow of incompressible fluid
which sticks to a body surface. The equation solutions show the resonant blowup
of the laminar flow, laminar-turbulent transition, the fluid detachment that
opens the way to solve the magnetic dynamo problem.


title: Novel dense crystalline packings of ellipsoids

abstract:
  An ellipsoid, the simplest non-spherical shape, has been extensively used as
models for elongated building blocks for a wide spectrum of molecular,
colloidal and granular systems. Yet the densest packing of congruent hard
ellipsoids, which is intimately related to the high-density phase of many
condensed matter systems, is still an open problem. We discover a novel dense
crystalline packing of ellipsoids containing 24 particles with a
quasi-square-triangular (SQ-TR) tiling arrangement, whose packing density
{\phi} exceeds that of the SM2 crystal for aspect ratios {\alpha} in (1.365,
1.5625), attaining a maximal {\phi} about 0.75806 at {\alpha} = 93/64. We show
that SQ-TR phase is thermodynamically stable at high densities over the
aforementioned {\alpha} range and report a novel phase diagram for self-dual
ellipsoids. The discovery of SQ-TR crystal suggests novel organizing principles
for non-spherical particles and self-assembly of colloidal systems.


title: Existence results for nonlinear elliptic problems on fractal domains

abstract:
  Some existence results for a parametric Dirichlet problem defined on the
Sierpi\'nski fractal are proved. More precisely, a critical point result for
differentiable functionals is exploited in order to prove the existence of a
well determined open interval of positive eigenvalues for which the problem
admits at least one non-trivial weak solution.


title: Stability for inner fibrations revisited

abstract:
  In this paper we prove a stability result for inner fibrations in terms of
the wide, or fat join operation on simplicial sets. We also prove some
additional results on inner anodyne morphisms that may be of independent
interest.


title: Existence of solutions for $p$-Laplacian discrete equations

abstract:
  This work is devoted to the study of the existence of at least one (non-zero)
solution to a problem involving the discrete $p$-Laplacian. As a special case,
we derive an existence theorem for a second-order discrete problem, depending
on a positive real parameter $\alpha$, whose prototype is given by $$ \left\{
\begin{array}{l} -\Delta^2u({k-1})=\alpha f(k,u(k)),\quad \forall\; k \in
{\mathbb{Z}}[1,T] \\ {u(0)=u({T+1})=0.}\\ \end{array} \right. $$ Our approach
is based on variational methods in finite-dimensional setting.


title: Proximal methods for stationary Mean Field Games with local couplings

abstract:
  We address the numerical approximation of Mean Field Games with local
couplings. For power-like Hamiltonians, we consider both unconstrained and
constrained stationary systems with density constraints in order to model hard
congestion effects. For finite difference discretizations of the Mean Field
Game system, we follow a variational approach. We prove that the aforementioned
schemes can be obtained as the optimality system of suitably defined
optimization problems. In order to prove the existence of solutions of the
scheme with a variational argument, the monotonicity of the coupling term is
not used, which allow us to recover general existence results. Next, assuming
next that the coupling term is monotone, the variational problem is cast as a
convex optimization problem for which we study and compare several proximal
type methods. These algorithms have several interesting features, such as
global convergence and stability with respect to the viscosity parameter, which
can eventually be zero. We assess the performance of the methods via numerical
experiments.


title:
East Asian Observations of Low Latitude Aurora during the Carrington
  Magnetic Storm

abstract:
  The magnetic storm around 1859 September 2, caused by so-called Carrington
flare, was the most intense in the history of modern scientific observations,
and hence is considered to be the benchmark event for space weather. The
magnetic storm caused worldwide observations of auroras even at very low
latitudes such as Hawaii, Panama, or Santiago, and the available magnetic field
measurement at Bombay, India, showed two peaks: the main was the Carrington
event which occurred in day time in East Asia, and a second storm after the
Carrington event which occurred at night in East Asia. In this paper, we
present a result from surveys of aurora records in East Asia, which provides
new information of the aurora activity of this important event. We found some
new East Asian records of low latitude aurora observations caused by the storm
which occurred after the Carrington event. The size of the aurora belt of the
second peak of the Carrington magnetic storm was even wider than usual
low-latitude aurora events.


title: Unsound Inferences Make Proofs Shorter

abstract:
  We give examples of calculi that extend Gentzen's sequent calculus LK by
unsound quantifier inferences in such a way that (i) derivations lead only to
true sequents, and (ii) proofs therein are non-elementarily shorter than
LK-proofs.


title:
Parametrized higher category theory and higher algebra: Expos\'e IV --
  Stability with respect to an orbital $\infty$-category

abstract:
  In this paper we develop a theory of stability for $G$-categories (presheaf
of categories on the orbit category of $G$), where $G$ is a finite group. We
give a description of Mackey functors as $G$-commutative monoids exploit it to
characterize $G$-spectra as the $G$-stabilization of $G$-spaces. As an
application of this we provide an alternative proof of a theorem by Guillou and
May. The theory here is developed in the more general setting of orbital
categories.


title:
On the Magnetic and Energy Characteristics of Recurrent Homologous Jets
  from An Emerging Flux

abstract:
  In this paper, we present the detailed analysis of recurrent homologous jets
originating from an emerging negative magnetic flux at the edge of an Active
Region. The observed jets show multi-thermal features. Their evolution shows
high consistence with the characteristic parameters of the emerging flux,
suggesting that with more free magnetic energy, the eruptions tend to be more
violent, frequent and blowout-like. The average temperature, average electron
number density and axial speed are found to be similar for different jets,
indicating that they should have been formed by plasmas from similar origins.
Statistical analysis of the jets and their footpoint region conditions reveals
a strong positive relationship between the footpoint-region total 131 {\AA}
intensity enhancement and jets' length/width. Stronger linearly positive
relationships also exist between the total intensity enhancement/thermal energy
of the footpoint regions and jets' mass/kinetic/thermal energy, with higher
cross-correlation coefficients. All the above results, together, confirm the
direct relationship between the magnetic reconnection and the jets, and
validate the important role of magnetic reconnection in transporting large
amount of free magnetic energy into jets. It is also suggested that there
should be more free energy released during the magnetic reconnection of blowout
than of standard jet events.


title: Multi-Path Feedback Recurrent Neural Network for Scene Parsing

abstract:
  In this paper, we consider the scene parsing problem and propose a novel
Multi-Path Feedback recurrent neural network (MPF-RNN) for parsing scene
images. MPF-RNN can enhance the capability of RNNs in modeling long-range
context information at multiple levels and better distinguish pixels that are
easy to confuse. Different from feedforward CNNs and RNNs with only single
feedback, MPF-RNN propagates the contextual features learned at top layer
through \textit{multiple} weighted recurrent connections to learn bottom
features. For better training MPF-RNN, we propose a new strategy that considers
accumulative loss at multiple recurrent steps to improve performance of the
MPF-RNN on parsing small objects. With these two novel components, MPF-RNN has
achieved significant improvement over strong baselines (VGG16 and Res101) on
five challenging scene parsing benchmarks, including traditional SiftFlow,
Barcelona, CamVid, Stanford Background as well as the recently released
large-scale ADE20K.


title: Threshold for blowup for equivariant wave maps in higher dimensions

abstract:
  We consider equivariant wave maps from $\mathbb{R}^{d+1}$ to $\mathbb{S}^d$
in supercritical dimensions $3\leq d\leq 6$. Using mixed numerical and analytic
methods, we show that the threshold of blowup is given by the codimension-one
stable manifold of a self-similar solution with one instability.


title: Logic programming: laxness and saturation

abstract:
  A propositional logic program $P$ may be identified with a $P_fP_f$-coalgebra
on the set of atomic propositions in the program. The corresponding
$C(P_fP_f)$-coalgebra, where $C(P_fP_f)$ is the cofree comonad on $P_fP_f$,
describes derivations by resolution. That correspondence has been developed to
model first-order programs in two ways, with lax semantics and saturated
semantics, based on locally ordered categories and right Kan extensions
respectively. We unify the two approaches, exhibiting them as complementary
rather than competing, reflecting the theorem-proving and proof-search aspects
of logic programming. While maintaining that unity, we further refine lax
semantics to give finitary models of logic programs with existential variables,
and to develop a precise semantic relationship between variables in logic
programming and worlds in local state.


title: Dynamical properties of the Rabi model

abstract:
  We study the dynamical properties of the quantum Rabi model within a
systematic expansion method. Based on the observation that the parity symmetry
of the Rabi model is kept during the evolution of the states, we decompose the
initial state and the time-dependent one into a part of a positive and a
negative parity expanded by the superposition of the coherent states. The
evolutions for the corresponding positive and the negative parity are obtained,
where the expansion coefficients in the dynamical equations are known from the
recurrence relation derived.


title: Random Forest for Label Ranking

abstract:
  Label ranking aims to learn a mapping from instances to rankings over a
finite number of predefined labels. Random forest is a powerful and one of the
most successful general-purpose machine learning algorithms of modern times. In
this paper, we present a powerful random forest label ranking method which uses
random decision trees to retrieve nearest neighbors. We have developed a novel
two-step rank aggregation strategy to effectively aggregate neighboring
rankings discovered by the random forest into a final predicted ranking.
Compared with existing methods, the new random forest method has many
advantages including its intrinsically scalable tree data structure, highly
parallel-able computational architecture and much superior performance. We
present extensive experimental results to demonstrate that our new method
achieves the highly competitive performance compared with state-of-the-art
methods for datasets with complete ranking and datasets with only partial
ranking information.


title:
3D Object Proposals using Stereo Imagery for Accurate Object Class
  Detection

abstract:
  The goal of this paper is to perform 3D object detection in the context of
autonomous driving. Our method first aims at generating a set of high-quality
3D object proposals by exploiting stereo imagery. We formulate the problem as
minimizing an energy function that encodes object size priors, placement of
objects on the ground plane as well as several depth informed features that
reason about free space, point cloud densities and distance to the ground. We
then exploit a CNN on top of these proposals to perform object detection. In
particular, we employ a convolutional neural net (CNN) that exploits context
and depth information to jointly regress to 3D bounding box coordinates and
object pose. Our experiments show significant performance gains over existing
RGB and RGB-D object proposal methods on the challenging KITTI benchmark. When
combined with the CNN, our approach outperforms all existing results in object
detection and orientation estimation tasks for all three KITTI object classes.
Furthermore, we experiment also with the setting where LIDAR information is
available, and show that using both LIDAR and stereo leads to the best result.


title:
A cevian locus and the geometric construction of a special elliptic
  curve

abstract:
  In a previous paper we defined the circumconic of a triangle $ABC$ with
respect to a point $P$ as the conic $\tilde C=T_{P'}^{-1}(N_{P'})$, where
$N_{P'}$ is the $9$-point conic for the quadrangle $ABCP'$ with respect to the
line at infinity, $P'$ is the isotomic conjugate of $P$ with respect to $ABC$,
and $T_{P'}$ is the affine map taking $ABC$ to the cevian triangle for $P'$. In
this paper we determine the locus of points for which a certain affine map
$\textsf{M}$ taking the circumconic $\tilde C$ to the inconic $\mathcal{I}$,
defined to be the unique conic tangent to the sides of $ABC$ at the traces of
the point $P$ on those sides, is a half-turn. This locus turns out to be an
elliptic curve minus six points, which can be constructed geometrically using a
family of affine maps defined for points on three open arcs of a circle.


title: Diffuse-field coherence of sensors with arbitrary directional responses

abstract:
  Knowledge of the diffuse-field coherence between array sensors is a basic
assumption for a wide range of array processing applications. Explicit
relations previously existed only for omnidirectional and first-order
directional sensors, or a restricted arrangement of differential patterns. We
present a closed-form formulation of the theoretical coherence function between
arbitrary directionally band-limited sensors for the general cases that a) the
responses of the individual sensors are known or estimated, and the coherence
needs to be known for an arbitrary arrangement, and b) that no information on
the sensor directionality or on array geometry exists, but calibration
measurements around the array are available.


title:
A software package for evaluating the performance of a star sensor
  operation

abstract:
  We have developed a low-cost off-the-shelf component star sensor (StarSense)
for use in minisatellites and CubeSats to determine the attitude of a satellite
in orbit. StarSense is an imaging camera with a limiting magnitude of 6.5,
which extracts information from star patterns it records in the images. The
star sensor implements a centroiding algorithm to find centroids of the stars
in the image, a Geometric Voting algorithm for star pattern identification, and
a QUEST algorithm for attitude quaternion calculation. Here, we describe the
software package to evaluate the performance of these algorithms as a star
sensor single operating system. We simulate the ideal case where sky background
and instrument errors are omitted, and a more realistic case where noise and
camera parameters are added to the simulated images. We evaluate such
performance parameters of the algorithms as attitude accuracy, calculation
time, required memory, star catalog size, sky coverage, etc., and estimate the
errors introduced by each algorithm. This software package is written for use
in MATLAB. The testing is parametrized for different hardware parameters, such
as the focal length of the imaging setup, the field of view (FOV) of the
camera, angle measurement accuracy, distortion effects, etc., and therefore,
can be applied to evaluate the performance of such algorithms in any star
sensor. For its hardware implementation on our StarSense, we are currently
porting the codes in form of functions written in C. This is done keeping in
view its easy implementation on any star sensor electronics hardware.


title:
On the Interior $W^{1,p}$ estimate of extension problem of fractional
  elliptic equation

abstract:
  In order to study Fractional operator, Caffarelli introduced the concept of
extension problem. Hence, for any fractional elliptic operator, we get a
degenerate elliptic equation. By studying the W^{1,p} regularity of extension
problem, we can get several L^p estimate of solution of original fractional
elliptic equation.


title:
Fano resonances in dielectric, metallic and metamaterial photonic
  structures

abstract:
  We investigate numerically Fano resonances excited in periodic arrays of
dielectric, metallic and left-handed cylinders. Of particular interest are Fano
resonances excited in the linear array of cylin- ders. We analyze spatial
distribution and symmetry of electromagnetic field and discuss the relation
between observed Fano resonances and frequency spectra of two-dimensional
arrays of cylinders.


title:
Magnetic excitation spectra of strongly correlated quasi-one dimensional
  systems: Heisenberg versus Hubbard-like behavior

abstract:
  We study the effects of charge degrees of freedom on the spin excitation
dynamics in quasi-one dimensional magnetic materials. Using the density matrix
renormalization group method, we calculate the dynamical spin structure factor
of the Hubbard model at half electronic filling on a chain and on a ladder
geometry, and compare the results with those obtained using the Heisenberg
model, where charge degrees of freedom are considered frozen. For both chains
and two-leg ladders, we find that the Hubbard model spectrum qualitatively
resembles the Heisenberg spectrum -- with low-energy peaks resembling spinonic
excitations -- already at intermediate on-site repulsion as small as $U/t \sim
2-3$, although ratios of peak intensities at different momenta continue
evolving with increasing $U/t$ converging only slowly to the Heisenberg limit.
We discuss the implications of these results for neutron scattering experiments
and we propose criteria to establish the values of $U/t$ of quasi-one
dimensional systems described by one-orbital Hubbard models from experimental
information.


title:
Alternative interpretation of the recent experimental results of
  angle-resolved photoemission spectroscopy on GaMnAs [Sci. Rep. 6, 27266
  (2016)]

abstract:
  Clarification of the position of the Fermi level ($E_\mathrm{F}$) is
important in understanding the origin of ferromagnetism in the prototypical
ferromagnetic semiconductor Ga$_{1-x}$Mn$_x$As (GaMnAs). In a recent
publication, Souma $et$ $al$. [Sci. Rep. $\mathbf{6}$, 27266 (2016)], have
investigated the band structure and the $E_\mathrm{F}$ position of GaMnAs using
angle-resolved photoemission spectroscopy (ARPES), and concluded that
$E_\mathrm{F}$ is located in the valence band (VB). However, this conclusion
contradicts a number of recent experimental results for GaMnAs, which showed
that $E_\mathrm{F}$ is located above the VB maximum in the impurity band (IB).
Here, we show an alternative interpretation of their ARPES experiments, which
is consistent with those recent experiments and supports the picture that
$E_\mathrm{F}$ is located above the VB maximum in the IB.


title: Temperature-Based Deep Boltzmann Machines

abstract:
  Deep learning techniques have been paramount in the last years, mainly due to
their outstanding results in a number of applications, that range from speech
recognition to face-based user identification. Despite other techniques
employed for such purposes, Deep Boltzmann Machines are among the most used
ones, which are composed of layers of Restricted Boltzmann Machines (RBMs)
stacked on top of each other. In this work, we evaluate the concept of
temperature in DBMs, which play a key role in Boltzmann-related distributions,
but it has never been considered in this context up to date. Therefore, the
main contribution of this paper is to take into account this information and to
evaluate its influence in DBMs considering the task of binary image
reconstruction. We expect this work can foster future research considering the
usage of different temperatures during learning in DBMs.


title:
A Bi-LSTM-RNN Model for Relation Classification Using Low-Cost Sequence
  Features

abstract:
  Relation classification is associated with many potential applications in the
artificial intelligence area. Recent approaches usually leverage neural
networks based on structure features such as syntactic or dependency features
to solve this problem. However, high-cost structure features make such
approaches inconvenient to be directly used. In addition, structure features
are probably domain-dependent. Therefore, this paper proposes a bi-directional
long-short-term-memory recurrent-neural-network (Bi-LSTM-RNN) model based on
low-cost sequence features to address relation classification. This model
divides a sentence or text segment into five parts, namely two target entities
and their three contexts. It learns the representations of entities and their
contexts, and uses them to classify relations. We evaluate our model on two
standard benchmark datasets in different domains, namely SemEval-2010 Task 8
and BioNLP-ST 2016 Task BB3. In the former dataset, our model achieves
comparable performance compared with other models using sequence features. In
the latter dataset, our model obtains the third best results compared with
other models in the official evaluation. Moreover, we find that the context
between two target entities plays the most important role in relation
classification. Furthermore, statistic experiments show that the context
between two target entities can be used as an approximate replacement of the
shortest dependency path when dependency parsing is not used.


title:
H$\ddot{o}$lder continuity for stochastic fractional heat equation with
  colored noise

abstract:
  In this paper, we consider semilinear stochastic fractional heat equation
$\frac{\partial}{\partial
t}u_{\beta,t}(x)=\triangle^{\alpha/2}u_{\beta,t}(x)+\sigma(u_{\beta,t}(x))\eta_{\beta}$.
The Gaussian noise $\eta_{\beta}$ is assumed to be colored in space with
covariance of the form
$E(\eta_{\beta}(t,x)\eta_{\beta}(s,y))=\delta(t-s)f_{\beta}(x-y)$, where
$f_{\beta}$ is the Riesz kernel $f_{\beta}(x)\propto |x|^{-\beta}$. We obtain
the spatial and temporal H$\ddot{\mbox{o}}$lder continuity of the mild
solution.


title: Dynamical structure factor of one-dimensional hard rods

abstract:
  The zero-temperature dynamical structure factor $S(q,\omega)$ of
one-dimensional hard rods is computed using state-of-the-art quantum Monte
Carlo and analytic continuation techniques, complemented by a Bethe Ansatz
analysis. As the density increases, $S(q,\omega)$ reveals a crossover from the
Tonks-Girardeau gas to a quasi-solid regime, along which the low-energy
properties are found in agreement with the nonlinear Luttinger liquid theory.
Our quantitative estimate of $S(q,\omega)$ extends beyond the low-energy limit
and confirms a theoretical prediction regarding the behavior of $S(q,\omega)$
at specific wavevectors $\mathcal{Q}_n=n 2 \pi/a$, where $a$ is the core
radius, resulting from the interplay of the particle-hole boundaries of
suitably rescaled ideal Fermi gases. We observe significant similarities
between hard rods and one-dimensional $^4$He at high density, suggesting that
the hard-rods model may provide an accurate description of dense
one-dimensional liquids of quantum particles interacting through a strongly
repulsive, finite-range potential.


title: Edge Clique Cover of Claw-free Graphs

abstract:
  The smallest number of cliques, covering all edges of a graph $ G $, is
called the (edge) clique cover number of $ G $ and is denoted by $ cc(G) $. It
is an easy observation that for every line graph $ G $ with $ n $ vertices,
$cc(G)\leq n $. G. Chen et al. [Discrete Math. 219 (2000), no. 1--3, 17--26;
MR1761707] extended this observation to all quasi-line graphs and questioned if
the same assertion holds for all claw-free graphs. In this paper, using the
celebrated structure theorem of claw-free graphs due to Chudnovsky and Seymour,
we give an affirmative answer to this question for all claw-free graphs with
independence number at least three. In particular, we prove that if $ G $ is a
connected claw-free graph on $ n $ vertices with $ \alpha(G)\geq 3 $, then $
cc(G)\leq n $ and equality holds if and only if $ G $ is either the graph of
icosahedron, or the complement of a graph on $10$ vertices called twister or
the $p^{th}$ power of the cycle $ C_n $, for $1\leq p \leq \lfloor
(n-1)/3\rfloor $.


title: Learning Temporal Transformations From Time-Lapse Videos

abstract:
  Based on life-long observations of physical, chemical, and biologic phenomena
in the natural world, humans can often easily picture in their minds what an
object will look like in the future. But, what about computers? In this paper,
we learn computational models of object transformations from time-lapse videos.
In particular, we explore the use of generative models to create depictions of
objects at future times. These models explore several different prediction
tasks: generating a future state given a single depiction of an object,
generating a future state given two depictions of an object at different times,
and generating future states recursively in a recurrent framework. We provide
both qualitative and quantitative evaluations of the generated results, and
also conduct a human evaluation to compare variations of our models.


title: Diffractive Imaging of Coherent Nuclear Motion in Isolated Molecules

abstract:
  Observing the motion of the nuclear wavepackets during a molecular reaction,
in both space and time, is crucial for understanding and controlling the
outcome of photoinduced chemical reactions. We have imaged the motion of a
vibrational wavepacket in isolated iodine molecules using ultrafast electron
diffraction with relativistic electrons. The time-varying interatomic distance
was measured with a precision 0.07 {\AA} and temporal resolution of 230 fs
full-width at half-maximum (FWHM). The method is not only sensitive to the
position but also the shape of the nuclear wavepacket.


title: Extremality of Convex Sets with Some Applications

abstract:
  In this paper we introduce an enhanced notion of extremal systems for sets in
locally convex topological vector spaces and obtain efficient conditions for
set extremality in the convex case. Then we apply this machinery to deriving
new calculus results on intersection rules for normal cones to convex sets and
on infimal convolutions of support functions.


title: Graph parameters, Ramsey theory and the speed of hereditary properties

abstract:
  The speed of a hereditary property $P$ is the number $P_n$ of $n$-vertex
labelled graphs in $P$. It is known that the rates of growth of $P_n$
constitute discrete layers and the speed jumps, in particular, from constant to
polynomial, from polynomial to exponential and from exponential to factorial.
One more jump occurs when the entropy $\lim_{n\to\infty}\frac{\log_2
P_n}{\binom{n}{2}}$ changes from 0 to a nonzero value. In the present paper,
for each of these jumps we identify a graph parameter responsible for it, i.e.
we show that a jump of the speed coincides with a jump of the respective
parameter from finitude to infinity. In particular, we show that the speed of a
hereditary property $P$ is sub-factorial if and only if the neighbourhood
diversity of graphs in $P$ is bounded by a constant, and that the entropy of a
hereditary property $P$ is 0 if and only if the VC-dimension of graphs in $P$
is bounded by a constant. All the result are obtained by Ramsey-type arguments.


title:
Quantum Key Distribution with Mismatched Measurements over Arbitrary
  Channels

abstract:
  In this paper, we derive key-rate expressions for different quantum key
distribution protocols. Our key-rate equations utilize multiple channel
statistics, including those gathered from mismatched measurement bases - i.e.,
when Alice and Bob choose incompatible bases. In particular, we will consider
an Extended B92 and a two-way semi-quantum protocol. For both these protocols,
we demonstrate that their tolerance to noise is higher than previously thought
- in fact, we will show the semi-quantum protocol can actually tolerate the
same noise level as the fully quantum BB84 protocol. Along the way, we will
also consider an optimal QKD protocol for various quantum channels. Finally,
all the key-rate expressions which we derive in this paper are applicable to
any arbitrary, not necessarily symmetric, quantum channel.


title: Morphology and displacement of dunes in a closed-conduit flow

abstract:
  The transport of solid particles entrained by a fluid flow is frequently
found in industrial applications. A better knowledge of it, is of importance to
improve particle related industrial processes. When shear stresses exerted by
the fluid on the bed of particles are bounded to some limits, a mobile layer of
particles known as bed-load takes place in which the particles stay in contact
with the fixed bed. If it takes place over a non-erodible ground, and if the
particle flow rate is small enough, an initial thin continuous layer of
particles becomes discontinuous and composed of isolated dunes. We present here
an experimental study to understand some features of the dynamics of isolated
dunes under a fluid flow using a closed-conduit experimental loop made of
transparent material. Acquired data concerns mainly dune morphology and
displacement velocity under different conditions: different types of beads
(diameters and densities) and different water flow conditions. We observed that
an initial pile of beads placed in the conduit is rapidly deformed by the water
flow, adopting a "croissant" shape, like barchan dunes found in deserts at a
much larger scale. We observed also self-similarity in dunes dimensions and
that dune displacement velocity scales with the inverse of their dimensions.
The variation of the dune displacement velocity with the fluid shear velocity
is discussed here.


title: Algorithmic complexity of quantum capacity

abstract:
  Recently the theory of communication developed by Shannon has been extended
to the quantum realm by exploiting the rules of quantum theory. This latter
stems on complex vector spaces. However complex (as well as real) numbers are
just idealizations and they are not available in practice where we can only
deal with rational numbers. This fact naturally leads to the question of
whether the developed notions of capacities for quantum channels truly catch
their ability to transmit information. Here we answer this question for the
quantum capacity. To this end we resort to the notion of semi-computability in
order to approximately (by rational numbers) describe quantum states and
quantum channel maps. Then we introduce algorithmic entropies (like algorithmic
quantum coherent information) and derive relevant properties for them. Finally
we define algorithmic quantum capacity and prove that it equals the standard
one.


title: Convex envelopes for fixed rank approximation

abstract:
  A convex envelope for the problem of finding the best approximation to a
given matrix with a prescribed rank is constructed. This convex envelope allows
the usage of traditional optimization techniques when additional constraints
are added to the finite rank approximation problem. Expression for the
dependence of the convex envelope on the singular values of the given matrix is
derived and global minimization properties are derived. The corresponding
proximity operator is also studied.


title: Generalized polarized manifolds with low second class

abstract:
  On a smooth complex projective variety $X$ of dimension $n$, consider an
ample vector bundle $\mathcal{E}$ of rank $r \leq n-2$ and an ample line bundle
$H$. A numerical character $m_2=m_2(X,\mathcal{E},H)$ of the triplet
$(X,\mathcal{E},H)$ is defined, extending the well-known second class of a
polarized manifold $(X,H)$, when either $n=2$ or $H$ is very ample. Under some
additional assumptions on $\mathcal{F}: = \mathcal{E} \oplus H^{\oplus
(n-r-2)}$, triplets $(X,\mathcal{E},H)$ as above whose $m_2$ is small with
respect to the invariants $d:=c_{n-2}(\mathcal{F})H^2$ and
$g:=1+\frac{1}{2}\big(K_X + c_1(\mathcal{F})+H\big) \cdot c_{n-2}(\mathcal{F})
\cdot H$ are studied and classified.


title: Lagrangian magnetic moment from polarization

abstract:
  An effective Lagrangian term for the electron magnetic moment, and more
generally electromagnetic form factors, is calculated by considering the
background field method. Two Fierz transformations are performed for a
one-photon exchange interaction, and the ambiguity in doing such
transformations is exploited. The resulting effective interaction may exhibit
an approximated rotational chiral symmetry either for the scalar-pseudoscalar
currents interaction or for the vector-axial currents interaction. The leading
terms in the expansion of the fermion determinant yield the leading QED
effective action with the complete one loop electromagnetic form factors. A
model is proposed to produce the tree level magnetic moment term.


title: Learning Bayesian Networks with Incomplete Data by Augmentation

abstract:
  We present new algorithms for learning Bayesian networks from data with
missing values using a data augmentation approach. An exact Bayesian network
learning algorithm is obtained by recasting the problem into a standard
Bayesian network learning problem without missing data. To the best of our
knowledge, this is the first exact algorithm for this problem. As expected, the
exact algorithm does not scale to large domains. We build on the exact method
to create an approximate algorithm using a hill-climbing technique. This
algorithm scales to large domains so long as a suitable standard structure
learning method for complete data is available. We perform a wide range of
experiments to demonstrate the benefits of learning Bayesian networks with such
new approach.


title: On sums of powers of almost equal primes

abstract:
  Let $k \ge 2$ and $s$ be positive integers, and let $n$ be a large positive
integer subject to certain local conditions. We prove that if $s \ge k^2+k+1$
and $\theta > 31/40$, then $n$ can be expressed as a sum $p_1^k + \dots +
p_s^k$, where $p_1, \dots, p_s$ are primes with $|p_j - (n/s)^{1/k}| \le
n^{\theta/k}$. This improves on earlier work by Wei and Wooley and by Huang who
proved similar theorems when $\theta > 19/24$.


title:
Boundary Korn Inequality and Neumann Problems in Homogenization of
  Systems of Elasticity

abstract:
  This paper concerns with a family of elliptic systems of linear elasticity
with rapidly oscillating periodic coefficients, arising in the theory of
homogenization. We establish uniform optimal regularity estimates for solutions
of Neumann problems in a bounded Lipschitz domain with $L^2$ boundary data. The
proof relies on a boundary Korn inequality for solutions of systems of linear
elasticity and uses a large-scale Rellich estimate obtained in
\cite{Shen-2016}.


title:
Compactifying the relative Picard functor over degenerations of
  varieties

abstract:
  Over a family of varieties with singular special fiber, the relative Picard
functor (i.e. the moduli space of line bundles) may fail to be compact. We
propose a stability condition for line bundles on reducible varieties that is
aimed at compactifying it. This stability condition generalizes the notion of
`balanced multidegree' used by Caporaso in compactifying the relative Picard
functor over families of curves. Unlike the latter, it is defined
`asymptotically'; an important theme of this paper is that although line
bundles on higher-dimensional varieties are more complicated than those on
curves, their behavior in terms of stability asymptotically approaches that of
line bundles on curves.
  Using this definition of stability, we prove that over a one-parameter family
of varieties having smooth total space, any line bundle on the generic fiber
can be extended to a unique semistable line bundle on the (possibly reducible)
special fiber, provided the special fiber is not too complicated in a
combinatorial sense.


title: Testing APSyn against Vector Cosine on Similarity Estimation

abstract:
  In Distributional Semantic Models (DSMs), Vector Cosine is widely used to
estimate similarity between word vectors, although this measure was noticed to
suffer from several shortcomings. The recent literature has proposed other
methods which attempt to mitigate such biases. In this paper, we intend to
investigate APSyn, a measure that computes the extent of the intersection
between the most associated contexts of two target words, weighting it by
context relevance. We evaluated this metric in a similarity estimation task on
several popular test sets, and our results show that APSyn is in fact highly
competitive, even with respect to the results reported in the literature for
word embeddings. On top of it, APSyn addresses some of the weaknesses of Vector
Cosine, performing well also on genuine similarity estimation.


title:
Bayesian selection for the l2-Potts model regularization parameter: 1D
  piecewise constant signal denoising

abstract:
  Piecewise constant denoising can be solved either by deterministic
optimization approaches, based on the Potts model, or by stochastic Bayesian
procedures. The former lead to low computational time but require the selection
of a regularization parameter, whose value significantly impacts the achieved
solution, and whose automated selection remains an involved and challenging
problem. Conversely, fully Bayesian formalisms encapsulate the regularization
parameter selection into hierarchical models, at the price of high
computational costs. This contribution proposes an operational strategy that
combines hierarchical Bayesian and Potts model formulations, with the double
aim of automatically tuning the regularization parameter and of maintaining
computational effciency. The proposed procedure relies on formally connecting a
Bayesian framework to a l2-Potts functional. Behaviors and performance for the
proposed piecewise constant denoising and regularization parameter tuning
techniques are studied qualitatively and assessed quantitatively, and shown to
compare favorably against those of a fully Bayesian hierarchical procedure,
both in accuracy and in computational load.


title: Forecasting the onset and course of mental illness with Twitter data

abstract:
  We developed computational models to predict the emergence of depression and
Post-Traumatic Stress Disorder in Twitter users. Twitter data and details of
depression history were collected from 204 individuals (105 depressed, 99
healthy). We extracted predictive features measuring affect, linguistic style,
and context from participant tweets (N=279,951) and built models using these
features with supervised learning algorithms. Resulting models successfully
discriminated between depressed and healthy content, and compared favorably to
general practitioners' average success rates in diagnosing depression. Results
held even when the analysis was restricted to content posted before first
depression diagnosis. State-space temporal analysis suggests that onset of
depression may be detectable from Twitter data several months prior to
diagnosis. Predictive results were replicated with a separate sample of
individuals diagnosed with PTSD (174 users, 243,775 tweets). A state-space time
series model revealed indicators of PTSD almost immediately post-trauma, often
many months prior to clinical diagnosis. These methods suggest a data-driven,
predictive approach for early screening and detection of mental illness.


title: On the instability of two entropic dynamical models

abstract:
  In this paper we study two entropic dynamical models from the viewpoint of
information geometry. We study the geometry structures of the associated
statistical manifolds. In order to analyse the character of the instability of
the systems, we obtain their geodesics and compute their Jacobi vector fields.
The results of this work improve and extend a recent advance in this topics
studied in [13]


title: Flux tubes at Finite Temperature

abstract:
  We show the flux tubes produced by static quark-antiquark, quark-quark and
quark-gluon charges at finite temperature. The sources are placed in the
lattice with fundamental and adjoint Polyakov loops. We compute the square
densities of the chromomagnetic and chromoelectric fields above and below the
phase transition. Our results are gauge invariant and produced in pure gauge
SU(3). The codes are written in CUDA and the computations are performed with
GPUs.


title:
Effect of Human Learning on the Transient Performance of Cloud-based
  Tiered Applications

abstract:
  Cloud based tiered applications are increasingly becoming popular, be it on
phones or on desktops. End users of these applications range from novice to
expert depending on how experienced they are in using them. With repeated usage
(practice) of an application, a user's think time gradually decreases, known as
learning phenomenon. In contrast to the popular notion of constant mean think
time of users across all practice sessions, decrease in mean think time over
practice sessions does occur due to learning. This decrease gives rise to a
different system workload thereby affecting the application's short-term
performance. However, such impact of learning on performance has never been
accounted for. In this work we propose a model that accounts for human learning
behavior in analyzing the transient (short-term) performance of a 3-tier cloud
based application. Our approach is based on a closed queueing network model. We
solve the model using discrete event simulation. In addition to the overall
mean System Response Time (SRT), our model solution also generates the mean
SRTs for various types (novice, intermediate, expert) of requests submitted by
users at various levels of their expertise. We demonstrate that our model can
be used to evaluate various what-if scenarios to decide the number of VMs we
need for each tier-a VM configuration-that would meet the response time SLA.
The results show that the lack of accountability of learning may lead to a
selection of an inappropriate VM configuration. The results further show that
the mean SRTs for various types of requests are better measures to consider in
VM allocation process in comparison to the overall mean SRT.


title: Purely infinite simple Kumjian-Pask algebras

abstract:
  Given any finitely aligned higher-rank graph $\Lambda$ and any unital
commutative ring $R$, the Kumjian-Pask algebra $\mathrm{KP}_R(\Lambda)$ is
known as the higher-rank generalization of Leavitt path algebras. After
characterizing simple Kumjian-Pask algebras by L.O. Clark and Y.E.P. Pangalela
(and others), we focus in this article on the purely infinite simple ones.
Briefly, we show that if $\mathrm{KP}_R(\Lambda)$ is simple and every vertex of
$\Lambda$ is reached from a generalized cycle with an entrance, then
$\mathrm{KP}_R(\Lambda)$ is purely infinite. We next prove a standard dichotomy
for simple Kumjian-Pask algebras: in the case that each vertex of $\Lambda$ is
reached only from finitely many vertices and $\mathrm{KP}_R(\Lambda)$ is
simple, then $\mathrm{KP}_R(\Lambda)$ is either purely infinite or locally
matritial. This result covers all unital simple Kumjian-Pask algebras.


title: Type-Directed Code Reuse using Integer Linear Programming

abstract:
  In many common scenarios, programmers need to implement functionality that is
already provided by some third party library. This paper presents a tool called
Hunter that facilitates code reuse by finding relevant methods in large code
bases and automatically synthesizing any necessary wrapper code. The key
technical idea underlying our approach is to use types to both improve search
results and guide synthesis. Specifically, our method computes similarity
metrics between types and uses this information to solve an integer linear
programming (ILP) problem in which the objective is to minimize the cost of
synthesis. We have implemented Hunter as an Eclipse plug-in and evaluate it by
(a) comparing it against S6, a state-of-the-art code reuse tool, and (b)
performing a user study. Our evaluation shows that Hunter compares favorably
with S6 and significantly increases programmer productivity.


title: Weak* Solutions II: The Vacuum in Lagrangian Gas Dynamics

abstract:
  We develop a framework in which to make sense of solutions containing the
vacuum in Lagrangian gas dynamics. At and near vacuum, the specific volume
becomes infinite and enclosed vacuums are represented by Dirac masses, so they
cannot be treated in the usual weak sense. However, the weak* solutions
recently introduced by the authors can be extended to include solutions
containing vacuums. We present a definition of these natural vacuum solutions
and provide explicit examples which demonstrate some of their features. Our
examples are isentropic for clarity, and we briefly discuss the extension to
the full $3\times3$ system of gas dynamics. We also extend our methods to
one-dimensional dynamic elasticity to show that fractures cannot form in an
entropy solution.


title: The Range of a Steiner Operation

abstract:
  This paper answers a fundamental question in the theory of Steiner operations
(StOps) as defined and studied in the monograph, "Global Methods for
Combinatorial Isoperimetric Problems" (GMCIP). StOps are morphisms for
combinatorial isoperimetric problems, analogous to Steiner symmetrization for
continuous isoperimetric problems. The usefulness of a StOp, Phi, a function
from the power set of V (a finite set) to the power set of V, depends on having
an efficient representation of its range. In GMCIP the problem was treated
case-by-case. In each case the StOp induced a partial order, P, on V so that
Range(Phi)=I(P), the set of all order ideals of P. Here we show (directly from
the axioms for a StOp) that every idempotent StOp admits such a representation
of its range (P is then called the StOp-order of Phi). That result leads to
another question: What additional structure does Range(Phi) have? The answer is
none. We show that every finite poset is the StOp-order of some idempotent
Steiner operation.


title:
Impact of g-factors and valleys on spin qubits in a silicon double
  quantum dot

abstract:
  We define single electron spin qubits in a silicon MOS double quantum dot
system. By mapping the qubit resonance frequency as a function of gate-induced
electric field, the spectrum reveals an anticrossing that is consistent with an
inter-valley spin-orbit coupling. We fit the data from which we extract an
inter-valley coupling strength of 43 MHz. In addition, we observe a narrow
resonance near the primary qubit resonance when we operate the device in the
(1,1) charge configuration. The experimental data is consistent with a
simulation involving two weakly exchanged-coupled spins with a g-factor
difference of 1 MHz, of the same order as the Rabi frequency. We conclude that
the narrow resonance is the result of driven transitions between the T- and T+
triplet states, using an ESR signal of frequency located halfway between the
resonance frequencies of the two individual spins. The findings presented here
offer an alternative method of implementing two-qubit gates, of relevance to
the operation of larger scale spin qubit systems.


title: Odd extensions of transitive groups via symmetric graphs

abstract:
  When dealing with symmetry properties of mathematical objects, one of the
fundamental questions is to determine their full automorphism group. In this
paper this question is considered in the context of even/odd permutations
dichotomy. More precisely: when is it that existence of automorphisms acting as
even permutations on the vertex set of a graph, called {\em even
automorphisms}, forces existence of automorphisms that act as odd permutations,
called {\em odd automorphisms}. As a first step towards resolving the above
question, a complete information on existence of odd automorphisms in cubic
symmetric graphs is given.


title:
Resolvent Estimates and Smoothing for Homogeneous Operators on Graded
  Lie Groups

abstract:
  By using commutator methods, we show uniform resolvent estimates and obtain
globally smooth operators for self-adjoint injective homogeneous operators $H$
on graded groups, including Rockland operators, sublaplacians and many others.
Left or right invariance is not required. Typically the globally smooth
operator has the form $T=V|H|^{1/2}$, where $V$ only depends on the homogeneous
structure of the group through Sobolev spaces, the homogeneous dimension and
the minimal and maximal dilation weights. For stratified groups improvements
are obtained, by using a Hardy-type inequality. Some of the results involve
refined estimates in terms of real interpolation spaces and are valid in an
abstract setting. Even for the commutative group $\R^N$ some new classes of
operators are treated.


title:
Metamorphoses of electronic structure of FeSe-based superconductors
  (Review article)

abstract:
  The electronic structure of FeSe, the simplest iron based superconductor
(Fe-SC), conceals a potential of dramatic increase of Tc that realizes under
pressure or in a single layer film. This is also the system where nematicity,
the phenomenon of a keen current interest, is most easy to study since it is
not accompanied by the antiferomagnetic transition like in all other Fe-SC's.
Here we overview recent experimental data on electronic structure of FeSe-based
superconductors: isovalently doped crystals, intercalates, and single layer
films, trying to clarify its topology and possible relation of this topology to
superconductivity. We argue that the marked differences between the
experimental and calculated band structures for all FeSe compounds can be
described by a hoping selective renormalization model for a spin/orbital
correlated state that may naturally explain both the evolution of the band
structure with temperature and nematicity.


title: Financial Market Dynamics: Superdiffusive or not?

abstract:
  The behavior of stock market returns over a period of 1-60 days has been
investigated for S&P 500 and Nasdaq within the framework of nonextensive
Tsallis statistics. Even for such long terms, the distributions of the returns
are non-Gaussian. They have fat tails indicating that the stock returns do not
follow a random walk model. In this work, a good fit to a Tsallis q-Gaussian
distribution is obtained for the distributions of all the returns using the
method of Maximum Likelihood Estimate. For all the regions of data considered,
the values of the scaling parameter q, estimated from one day returns, lie in
the range 1.4 to 1.65. The estimated inverse mean square deviations (beta) show
a power law behavior in time with exponent values between -0.91 and -1.1
indicating normal to mildly subdiffusive behavior. Quite often, the dynamics of
market return distributions is modelled by a Fokker-Plank (FP) equation either
with a linear drift and a nonlinear diffusion term or with just a nonlinear
diffusion term. Both of these cases support a q-Gaussian distribution as a
solution. The distributions obtained from current estimated parameters are
compared with the solutions of the FP equations. For negligible drift term, the
inverse mean square deviations (betaFP) from the FP model follow a power law
with exponent values between -1.25 and -1.48 indicating superdiffusion. When
the drift term is non-negligible, the corresponding betaFP do not follow a
power law and become stationary after certain characteristic times that depend
on the values of the drift parameter and q. Neither of these behaviors is
supported by the results of the empirical fit.


title: Exact solutions of (0,2) Landau-Ginzburg models

abstract:
  In this paper we study the low energy physics of Landau-Ginzburg models with
N=(0,2) supersymmetry. We exhibit a number of classes of relatively simple LG
models where the conformal field theory at the low energy fixed point can be
explicitly identified. One interesting class of fixed points can be thought of
as "heterotic" minimal models. Other examples include N=(0,2) renormalization
group flows that end up at N=(2,2) minimal models and models with non-abelian
symmetry.


title: Precise Condition Synthesis for Program Repair

abstract:
  Due to the difficulty of repairing defect, many research efforts have been
devoted into automatic defect repair. Given a buggy program that fails some
test cases, a typical automatic repair technique tries to modify the program to
make all tests pass. However, since the test suites in real world projects are
usually insufficient, aiming at passing the test suites often leads to
incorrect patches.
  In this paper we aim to produce precise patches, that is, any patch we
produce has a relatively high probability to be correct. More concretely, we
focus on condition synthesis, which was shown to be able to repair more than
half of the defects in existing approaches. Our key insight is threefold.
First, it is important to know what variables in a local context should be used
in an "if" condition, and we propose a sorting method based on the dependency
relations between variables. Second, we observe that the API document can be
used to guide the repair process, and propose document analysis technique to
further filter the variables. Third, it is important to know what predicates
should be performed on the set of variables, and we propose to mine a set of
frequently used predicates in similar contexts from existing projects.
  We develop a novel program repair system, ACS, that could generate precise
conditions at faulty locations. Furthermore, given the generated conditions are
very precise, we can perform a repair operation that is previously deemed to be
too overfitting: directly returning the test oracle to repair the defect. Using
our approach, we successfully repaired 17 defects on four projects of
Defects4J, which is the largest number of fully automatically repaired defects
reported on the dataset so far. More importantly, the precision of our approach
in the evaluation is 73.9%, which is significantly higher than previous
approaches, which are usually less than 40%.


title: Maximal prime homomorphic images of mod-$p$ Iwasawa algebras

abstract:
  Let $k$ be a finite field of characteristic $p$, and $G$ a compact $p$-adic
analytic group. Write $kG$ for the completed group ring of $G$ over $k$. In
this paper, we describe the structure of the ring $kG/P$, where $P$ is a
minimal prime ideal of $kG$. We give an isomorphism between $kG/P$ and a matrix
ring with coefficients in the ring $(k'G')_\alpha$, where $k'/k$ is a finite
field extension, $G'$ is a large subquotient of $G$ with no finite normal
subgroups, and $(-)_\alpha$ is a "twisting" operation that preserves several
desirable properties of the ring structure. We demonstrate an application of
this isomorphism by setting up correspondences between certain ideals and
subrings of $kG$ and those of $(k'G')_\alpha$, and showing that these
correspondences often preserve some useful properties, such as
almost-faithfulness of an ideal, or control of an ideal by a closed normal
subgroup.


title:
Topological defect dynamics of vortex lattices in Bose--Einstein
  condensates

abstract:
  Vortex lattices in rapidly rotating Bose--Einstein condensates are systems of
topological excitations that arrange themselves into periodic patterns. Here we
show how phase-imprinting techniques can be used to create a controllable
number of defects in these lattices and examine the resulting dynamics. Even
though we describe our system using the mean-field Gross--Pitaevskii theory,
the full range of many particle effects among the vortices can be studied. In
particular we find the existence of localized vacancies that are quasi-stable
over long periods of time, and characterize the effects on the background
lattice through use of the orientational correlation function, and Delaunay
triangulation.


title: Shortcuts to isothermality and nonequilibrium work relations

abstract:
  In conventional thermodynamics, it is widely acknowledged that the
realization of an isothermal process for a system requires a quasi-static
controlling protocol. Here we propose and design a strategy to realize a
finite-rate isothermal transition from an equilibrium state to another one with
same temperature, which is named shortcut to isothermality~(STI). By using STI,
we unexpectedly derive three nonequilibrium work relations, including an
identity between the free energy difference and the mean work due to the
potential of the original system, a generalized Jarzynski equality, and the
inverse relationship between the irreversible work and the total driving time.
We numerically confirm these three relations by considering the motion of a
Brownian particle trapped in a harmonic potential and dragged by a
time-dependent force.


title:
Design of a High-bunch-charge 112-MHz Superconducting RF Photoemission
  Electron Source

abstract:
  High-bunch-charge photoemission electron-sources operating in a continuous
wave (CW) mode are required for many advanced applications of particle
accelerators, such as electron coolers for hadron beams, electron-ion
colliders, and free-electron lasers (FELs). Superconducting RF (SRF) has
several advantages over other electron-gun technologies in CW mode as it offers
higher acceleration rate and potentially can generate higher bunch charges and
average beam currents. A 112 MHz SRF electron photoinjector (gun) was developed
at Brookhaven National Laboratory (BNL) to produce high-brightness and
high-bunch-charge bunches for the Coherent electron Cooling Proof-of-Principle
(CeC PoP) experiment. The gun utilizes a quarter-wave resonator (QWR) geometry
for assuring beam dynamics, and uses high quantum efficiency (QE) multi-alkali
photocathodes for generating electrons.


title: On the Observation and Simulation of Solar Coronal Twin Jets

abstract:
  We present the first observation, analysis and modeling of solar coronal twin
jets, which occurred after a preceding jet. Detailed analysis on the kinetics
of the preceding jet reveals its blowout-jet nature, which resembles the one
studied in Liu et al. 2014. However the erupting process and kinetics of the
twin jets appear to be different from the preceding one. In lack of the
detailed information on the magnetic fields in the twin jet region, we instead
use a numerical simulation using a three-dimensional (3D) MHD model as
described in Fang et al. 2014, and find that in the simulation a pair of twin
jets form due to reconnection between the ambient open fields and a highly
twisted sigmoidal magnetic flux which is the outcome of the further evolution
of the magnetic fields following the preceding blowout jet. Based on the
similarity between the synthesized and observed emission we propose this
mechanism as a possible explanation for the observed twin jets. Combining our
observation and simulation, we suggest that with continuous energy transport
from the subsurface convection zone into the corona, solar coronal twin jets
could be generated in the same fashion addressed above.


title:
The thermodynamic meaning of local temperature of nonequilibrium open
  quantum systems

abstract:
  Measuring the local temperature of nanoscale systems out of equilibrium has
emerged as a new tool to study local heating effects and other local thermal
properties of systems driven by external fields. Although various experimental
protocols and theoretical definitions have been proposed to determine the local
temperature, the thermodynamic meaning of the measured or defined quantities
remains unclear. By performing analytical and numerical analysis of bias-driven
quantum dot systems both in the noninteracting and strongly-correlated regimes,
we elucidate the underlying physical meaning of local temperature as determined
by two definitions: the zero-current condition that is widely used but not
measurable, and the minimal-perturbation condition that is experimentally
realizable. We show that, unlike the zero-current one, the local temperature
determined by the minimalperturbation protocol establishes a quantitative
correspondence between the nonequilibrium system of interest and a reference
equilibrium system, provided the probed system observable and the related
electronic excitations are fully local. The quantitative correspondence thus
allows the well-established thermodynamic concept to be extended to
nonequilibrium situations.


title:
Fractional Quantum Hall Bilayers at Half-Filling: Tunneling-driven
  Non-Abelian Phase

abstract:
  Multicomponent quantum Hall systems with internal degrees of freedom provide
a fertile ground for the emergence of exotic quantum liquids. Here we
investigate the possibility of non-Abelian topological order in the half-filled
fractional quantum Hall (FQH) bilayer system driven by the tunneling effect
between two layers. By means of the state-of-the-art density-matrix
renormalization group, we unveil "finger print" evidence of the non-Abelian
Moore-Read Pfaffian state emerging in the intermediate-tunneling regime,
including the ground-state degeneracy on the torus geometry and the topological
entanglement spectroscopy (entanglement spectrum and topological entanglement
entropy) on the spherical geometry, respectively. Remarkably, the phase
transition from the previously identified Abelian $(331)$ Halperin state to the
non-Abelian Moore-Read Pfaffian state is determined to be continuous, which is
signaled by the continuous evolution of the universal part of the entanglement
spectrum, and discontinuities in the excitation gap and the derivative of the
ground-state energy. Our results not only provide a "proof-of-principle"
demonstration of realizing a non-Abelian state through coupling different
degrees of freedom, but also open up a possibility in FQH bilayer systems for
detecting different chiral $p-$wave pairing states.


title: A class of Ramsey-extremal hypergraphs

abstract:
  In 1991, McKay and Radziszowski proved that, however each 3-subset of a
13-set is assigned one of two colours, there is some 4-subset whose four
3-subsets have the same colour. More than 25 years later, this remains the only
non-trivial classical Ramsey number known for hypergraphs. In this article, we
find all the extremal colourings of the 3-subsets of a 12-set and list some of
their properties. Using the catalogue, we provide an answer to a question of
Dudek, Fleur, Mubayi and R\"odl about the size-Ramsey numbers of hypergraphs.


title:
Magnetic order and spin-orbit coupled Mott state in double perovskite
  (La$_{1-x}$Sr$_x$)$_2$CuIrO$_6$

abstract:
  Double-perovskite oxides that contain both 3d and 5d transition metal
elements have attracted growing interest as they provide a model system to
study the interplay of strong electron interaction and large spin-orbit
coupling (SOC). Here, we report on experimental and theoretical studies of the
magnetic and electronic properties of double-perovskites
(La$_{1-x}$Sr$_x$)$_2$CuIrO$_6$ ($x$ = 0.0, 0.1, 0.2, and 0.3). The undoped
La$_2$CuIrO$_6$ undergoes a magnetic phase transition from paramagnetism to
antiferromagnetism at T$_N$ $\sim$ 74 K and exhibits a weak ferromagnetic
behavior below $T_C$ $\sim$ 52 K. Two-dimensional magnetism that was observed
in many other Cu-based double-perovskites is absent in our samples, which may
be due to the existence of weak Cu-Ir exchange interaction. First-principle
density-functional theory (DFT) calculations show canted antiferromagnetic
(AFM) order in both Cu$^{2+}$ and Ir$^{4+}$ sublattices, which gives rise to
weak ferromagnetism. Electronic structure calculations suggest that
La$_2$CuIrO$_6$ is an SOC-driven Mott insulator with an energy gap of $\sim$
0.3 eV. Sr-doping decreases the magnetic ordering temperatures ($T_N$ and
$T_C$) and suppresses the electrical resistivity. The high temperatures
resistivity can be fitted using a variable-range-hopping model, consistent with
the existence of disorders in these double-pervoskite compounds.


title: The Movie Graph Argument Revisited

abstract:
  In this paper, we reexamine the Movie Graph Argument, which demonstrates a
basic incompatibility between computationalism and materialism. We discover
that the incompatibility is only manifest in singular classical-like universes.
If we accept that we live in a Multiverse, then the incompatibility goes away,
but in that case another line of argument shows that with computationalism, the
fundamental, or primitive materiality has no causal influence on what is
observed, which must must be derivable from basic arithmetic properties.


title: Raman scattering in transition metal dichalcogenides MTe2 (M = Mo, W)

abstract:
  We performed comparable polarized Raman scattering studies of MoTe2 and WTe2.
By rotating crystals to tune the angle between the principal axis of the
crystals and the polarization of the incident/scattered light, we obtained the
angle dependence of the intensities for all the observed modes, which is
perfectly consistent with careful symmetry analysis. Combining these results
with first-principles calculations, we clearly identified the observed phonon
modes in the different phases of both crystals. Fifteen Raman-active phonon
modes (10Ag+5Bg) in the high-symmetry phase 1T'-MoTe2 (300 K) were well
assigned, and all the symmetry-allowed Raman modes (11A1+6A2) in the
low-symmetry phase Td-MoTe2 (10 K) and 12 Raman phonons (8A1+4A2) in Td-WTe2
were observed and identified. The present work provides basic information about
the lattice dynamics in transition-metal dichalcogenides and may shed some
light on the understanding of the extremely large magnetoresistance (MR) in
this class of materials.


title: Two coupled nonlinear cavities in a driven-dissipative environment

abstract:
  We investigate two coupled nonlinear cavities that are coherently driven in a
dissipative environment. We perform semiclassical, numerical and analytical
quantum studies of this dimer model when both cavities are symmetrically
driven. In the semiclassical analysis, we find steady-state solutions with
different photon occupations in two cavities. Such states can be considered
analogs of the closed system double well symmetry breaking states. We analyze
the occurrence and properties of these localized states in the system parameter
space and examine how the symmetry breaking states, in form of a bistable pair,
are associated to the single cavity bistable behavior. In a full quantum
calculation of the master equation dynamics that includes quantum fluctuations,
the symmetry breaking states and bistability disappear due to the quantum
fluctuations. In quantum trajectory picture, we observe enhanced quantum jumps
and switching which indicate the presence of the underlying semiclassical
symmetry breaking states. Finally, we present a set of analytical solutions for
the steady state correlation functions using the complex P-representation and
discuss its regime of validity.


title:
Sum Secrecy Rate Maximization for Full-Duplex Two-Way Relay Networks
  Using Alamouti-based Rank-Two Beamforming

abstract:
  Consider a two-way communication scenario where two single-antenna nodes,
operating under full-duplex mode, exchange information to one another through
the aid of a (full-duplex) multi-antenna relay, and there is another
single-antenna node who intends to eavesdrop. The relay employs artificial
noise (AN) to interfere the eavesdropper's channel, and amplify-forward (AF)
Alamouti-based rank-two beamforming to establish the two-way communication
links of the legitimate nodes. Our problem is to optimize the rank-two
beamformer and AN covariance for sum secrecy rate maximization (SSRM). This
SSRM problem is nonconvex, and we develop an efficient solution approach using
semidefinite relaxation (SDR) and minorization-maximization (MM). We prove that
SDR is tight for the SSRM problem and thus introduces no loss. Also, we
consider an inexact MM method where an approximately but computationally cheap
MM solution update is used in place of the exact update in conventional MM. We
show that this inexact MM method guarantees convergence to a stationary
solution to the SSRM problem. The effectiveness of our proposed approach is
further demonstrated by an energy-harvesting scenario extension, and by
extensive simulation results.


title:
CP sensitive observables of a hypothetical heavy spin-0 particle with
  $\gamma\gamma-$interactions dominant

abstract:
  We study observables sensitive to tensor structure of interactions of a
hypothetical heavy spin-0 particle. It is assumed that the interactions of this
particle are primary with photons; interactions with vector bosons $gg$, $WW$,
$ZZ$, and quarks $t\bar{t}$ are suppressed. The above assumptions favor the
production of this hypothetical particle through the vector boson fusion
mechanism structurally dominated by $\gamma \gamma$ and $\gamma Z$
interactions. This particle will be produced in association with two light
quarks. It is shown that the difference in azimuthal angle between the tagging
jets provides an observable sensitive to the CP properties of this hypothetical
particle.


title:
Spatially localized self-assembly driven by electrically charged phase
  separation

abstract:
  Self-assembly driven by phase separation coupled to Coulombic interactions is
fundamental to a wide range of applications, examples of which include soft
matter lithography via di-block copolymers, membrane design using
polyelectrolytes, and renewable energy applications based on complex
nano-materials, such as ionic liquids. The most common mean field framework for
these problems is the non-local Cahn-Hilliard (a.k.a. Ohta-Kawasaki) framework.
In this work, we study the emergence of spatially localized states in both the
classical and the extended Ohta-Kawasaki model. The latter also accounts for:
(i) asymmetries in long-range Coulomb interactions that are manifested by
differences in the dielectric response, and (ii) asymmetric short-range
interactions that correspond to differences in the chemical potential between
two materials phases. It is shown that in one space dimension (1D) there is a
multiplicity of coexisting localized solutions, which organize in the
homoclinic snaking structure, bearing similarity to dissipative systems. In
addition, an analysis of 2D extension is performed and distinct instability
mechanisms (related to extended and localized modes) of localized stripes are
discussed with respect to model parameters and domain size. Finally,
implications to localized hexagonal patterns are also made. The insights
provide an efficient mechanistic framework to design and control localized
self-assembly that might be a plausible strategy for low cost of nano
electronic applications, i.e., a rather simple nano scale fabrication of
isolated morphologies.


title: Differentiation via Logarithmic Expansions

abstract:
  In this note, we introduce a new finite difference approximation called the
Black-Box Logarithmic Expansion Numerical Derivative (BLEND) algorithm, which
is based on a formal logarithmic expansion of the differentiation operator.
BLEND capitalizes on parallelization and provides derivative approximations of
arbitrarily precision, i.e., our analysis can be used to determine the number
of terms in the series expansion to guarantee a specified number of decimal
places of accuracy. Furthermore, in the vector setting, the complexity of the
resulting directional derivative is independent of the dimension of the
parameter.


title: Star-product on complex sphere $\mathbb{S}^{2n}$

abstract:
  We construct a $U_q(\mathrm{so}(2n+1))$-equivariant local star-product on the
complex sphere $\mathbb{S}^{2n}$ as a Non-Levi conjugacy class
$SO(2n+1)/SO(2n)$.


title:
Implications of quantum ambiguities in k=1 loop quantum cosmology:
  distinct quantum turnarounds and the super-Planckian regime

abstract:
  The spatially closed Friedmann-Lema\^{i}tre-Robertson-Walker model in loop
quantum cosmology admits two inequivalent consistent quantizations: one based
on expressing the field strength in terms of the holonomies over closed loops,
and, another using a connection operator and open holonomies. Using the
effective dynamics, we investigate the phenomenological differences between the
two quantizations for the single fluid and the two fluid scenarios with various
equations of state, including the phantom matter. We show that a striking
difference between the two quantizations is the existence of two distinct
quantum turnarounds, either bounces or recollapses, in the connection
quantization, in contrast to a single distinct quantum bounce or a recollapse
in the holonomy quantization. These results generalize an earlier result on the
existence of two distinct quantum bounces for stiff matter by Corichi and
Karami. However, we find that in certain situations two distinct quantum
turnarounds can become virtually indistinguishable. And depending on the
initial conditions, a pure quantum cyclic universe can also exist undergoing a
quantum bounce and a quantum recollapse. We show that for various equations of
states, connection based quantization leads to super-Planckian values of the
energy density and the expansion scalar at quantum turnarounds. Interestingly,
we find that very extreme energy densities can also occur for the holonomy
quantization, breaching the maximum allowed density in the spatially flat loop
quantized model. However, the expansion scalar in all these cases is bounded by
a universal value.


title:
Unusual Fe-H bonding associated with oxygen vacancies at the (001)
  surface of Fe3O4

abstract:
  An unusual Fe-H bonding rather than conventional OH bonding is identified at
Fe3O4 (001) surface. This abnormal behavior is associated with the oxygen
vacancies which exist on the surface region but also penetrate deep into the
bulk Fe3O4. In contrast, OH bonding becomes preferential as generally expected
on an ozone processed surface, which has appreciably less oxygen vacancies.
Such bonding site selective behavior, depending on oxygen vacancy
concentrations, is further confirmed with DFT calculations. The results
demonstrate an opportunity for tuning the chemical properties of oxide surfaces
or oxide clusters.


title: Theory of quantum dissipation in a class of non-Gaussian environments

abstract:
  In this work we construct a novel dissipaton-equation-of-motion (DEOM) theory
in quadratic bath coupling environment, based an extended algebraic statistical
quasi-particle approach. To validate the new ingredient of the underlying
dissipaton algebra, we derive an extended Zusman equation via a totally
different approach. We prove that the new theory, if it starts with the
identical setup, constitutes the dynamical resolutions to the extended Zusman
equation. Thus, we verify the generalized (non-Gaussian) Wick's theorem with
dissipatons-pair added. This new algebraic ingredient enables the dissipaton
approach being naturally extended to nonlinear coupling environments. Moreover,
it is noticed that, unlike the linear bath coupling case, the influence of a
non-Gaussian environment cannot be completely characterized with the linear
response theory. The new theory has to take this fact into account. The
developed DEOM theory manifests the dynamical interplay between dissipatons and
nonlinear bath coupling descriptors that will be specified. Numerical
demonstrations will be given with the optical line shapes in quadratic coupling
environment.


title:
Hierarchical Attention Model for Improved Machine Comprehension of
  Spoken Content

abstract:
  Multimedia or spoken content presents more attractive information than plain
text content, but the former is more difficult to display on a screen and be
selected by a user. As a result, accessing large collections of the former is
much more difficult and time-consuming than the latter for humans. It's
therefore highly attractive to develop machines which can automatically
understand spoken content and summarize the key information for humans to
browse over. In this endeavor, a new task of machine comprehension of spoken
content was proposed recently. The initial goal was defined as the listening
comprehension test of TOEFL, a challenging academic English examination for
English learners whose native languages are not English. An Attention-based
Multi-hop Recurrent Neural Network (AMRNN) architecture was also proposed for
this task, which considered only the sequential relationship within the speech
utterances. In this paper, we propose a new Hierarchical Attention Model (HAM),
which constructs multi-hopped attention mechanism over tree-structured rather
than sequential representations for the utterances. Improved comprehension
performance robust with respect to ASR errors were obtained.


title: A light front quark-diquark model for the nucleons

abstract:
  We present a quark-diquark model for the nucleons where the light front wave
functions are constructed from the soft-wall AdS/QCD prediction. The model is
consistent with quark counting rule and Drell-Yan-West relation. The model
reproduces the scale evolution of unpolarized PDF of proton for a wide range of
energy scale. Helicity and transversity distributions for the proton predicted
in this model agree with phenomenological fits. The axial and tensor charges
are also shown to agree with the experimental data. The model can be used to
evaluate distributions like GPDS, TMDs etc. and their scale evolutions.


title: Standard Model as the topological material

abstract:
  Study of the Weyl and Dirac topological materials (topological semimetals,
insulators, superfluids and superconductors) opens the route for the
investigation of the topological quantum vacua of relativistic fields. The
symmetric phase of the Standard Model (SM), where both electroweak and chiral
symmetry are not broken, represents the topological semimetal. The vacua of the
SM (and its extensions) in the phases with broken Electroweak symmetry
represent the topological insulators of different types. We discuss in details
the topological invariants in both symmetric and broken phases and establish
their relation to the stability of vacuum.


title: Bakry-Emery curvature and diameter bounds on graphs

abstract:
  We prove diameter bounds for graphs having positive Ricci-curvature bound in
Bakry-Emery sense. One result using only curvature and maximal vertex degree is
sharp in case of hypercubes. The other result depends on an additional
dimension bound, but is independent of the vertex degree. In particular, the
second result is the first Bonnet-Myers type theorem for unbounded graph
Laplacians. Moreover, our results improve diameter bounds from [6] and [10].


title:
Universality and critical behavior of the dynamical Mott transition in a
  system with long-range interactions

abstract:
  We study numerically the voltage-induced breakdown of a Mott insulating phase
in a system of charged classical particles with long-range interactions. At
half-filling on a square lattice this system exhibits Mott localization in the
form of a checkerboard pattern. We find universal scaling behavior of the
current at the dynamic Mott insulator-metal transition and calculate scaling
exponents corresponding to the transition. Our results are in agreement, up to
a difference in universality class, with recent experimental evidence of
dynamic Mott transition in a system of interacting superconducting vortices.


title: LC/ESI-MS analysis of underivatized amino acids and mass spectrum

abstract:
  We report the method of LC/ESI-MS analysis of underivatized amino acids with
corresponding mass spectrum and fragmentation patterns. Diagnostic product ions
determined by mass spectrometry can support the qualitative identification and
quantitative estimation of individual amino acids. Therefore, the optimization
of chromatographic separation using the ion-pairing reagent (i.e.,
Nonafluoropentanoic acid, NFPA) is useful for the evaluation of target amino
acid and for further compound-specific nitrogen isotope studies of amino acids.


title: Multiversion Altruistic Locking

abstract:
  This paper builds on altruistic locking which is an extension of 2PL. It
allows more relaxed rules as compared to 2PL. But altruistic locking too
enforces some rules which disallow some valid schedules (present in VSR and
CSR) to be passed by AL. This paper proposes a multiversion variant of AL which
solves this problem. The report also discusses the relationship or comparison
between different protocols such as MAL and MV2PL, MAL and AL, MAL and 2PL and
so on. This paper also discusses the caveats involved in MAL and where it lies
in the Venn diagram of multiversion serializable schedule protocols. Finally,
the possible use of MAL in hybrid protocols and the parameters involved in
making MAL successful are discussed.


title:
Three-Dimensional Aquila Rift: Magnetized HI Arch Anchored by Molecular
  Complex

abstract:
  Three dimensional structure of the Aquila Rift of magnetized neutral gas is
investigated by analyzing HI and CO line data. The projected distance on the
Galactic plane of the HI arch of the Rift is ~250 pc from the Sun. The HI arch
emerges at l~ 30 deg, reaches to altitudes as high as ~ 500 pc above the plane
at l~ 350deg, and returns to the disk at l~270 deg. The extent of arch at
positive latitudes is ~1 kpc and radius is ~100 pc. The eastern root is
associated with the giant molecular cloud complex, which is the main body of
the optically defined Aquila Rift. The HI and molecular masses of the Rift are
estimated to be M_HI~1.4x10^5Msun and M_H2 ~3x10^5 Msun. Gravitational energies
to lift the gases to their heights are E_grav: HI ~1.4x10^51 and E_grav: H_2
~0.3x10^51 erg, respectively. Magnetic field is aligned along the HI arch of
the Rift, and the strength is measured to be B~10 microG using Faraday rotation
measures of extragalactic radio sources. The magnetic energy is estimated to be
E_mag~1.2x10^51 erg. A possible mechanism of formation of the Aquila Rift is
proposed in terms of interstellar magnetic inflation by a sinusoidal Parker
instability of wavelength of ~2.5 kpc and amplitude ~500 pc.


title: A generalized lower bound theorem for balanced manifolds

abstract:
  A simplicial complex of dimension $d-1$ is said to be balanced if its graph
is $d$-colorable. Juhnke-Kubitzke and Murai proved an analogue of the
generalized lower bound theorem for balanced simplicial polytopes. We establish
a generalization of their result to balanced triangulations of closed homology
manifolds and balanced triangulations of orientable homology manifolds with
boundary under an additional assumption that all proper links of these
triangulations have the weak Lefschetz property. As a corollary, we show that
if $\Delta$ is an arbitrary balanced triangulation of any closed homology
manifold of dimension $d-1 \geq 3$, then $2h_2(\Delta) - (d-1)h_1(\Delta) \geq
4{d \choose 2}(\tilde{\beta}_1(\Delta)-\tilde{\beta}_0(\Delta))$, thus
verifying a conjecture by Klee and Novik. To prove these results we develop the
theory of flag $h''$-vectors.


title: Decay estimates for fractional wave equations on H-type groups

abstract:
  The aim of this paper is to establish the decay estimate for the fractional
wave equation semigroup on H-type groups given by $e^{it\Delta^\alpha}$,
$0<\alpha<1$. Combing the dispersive estimate and a standard duality argument,
we also derive the corresponding Strichartz inequalties.


title: Charged Lepton Flavor-violating Transitions in Color Octet Model

abstract:
  We study charged lepton flavor-violating (LFV) transitions in the color octet
model that generates neutrino mass and lepton mixing at one loop. By taking
into account neutrino oscillation data and assuming octet particles of TeV
scale mass, we examine the feasibility to detect these transitions in current
and future experiments. We find that for general values of parameters the
branching ratios for LFV decays of the Higgs and $Z$ bosons are far below
current and even future experimental bounds. For LFV transitions of the muon,
the present bounds can be satisfied generally, while future sensitivities could
distinguish between the singlet and triplet color-octet fermions. The triplet
case could be ruled out by future $\mu-e$ conversion in nuclei, and for the
singlet case the conversion and the decays $\mu\to 3e,~e\gamma$ play
complementary roles in excluding relatively low mass regions of the octet
particles.


title:
Characterization of self-adjoint extensions for discrete symplectic
  systems

abstract:
  All self-adjoint extensions of minimal linear relation associated with the
discrete symplectic system are characterized. Especially, for the scalar case
on a finite discrete interval some equivalent forms and the uniqueness of the
given expression are discussed and the Krein--von Neumann extension is
described explicitly. In addition, a limit point criterion for symplectic
systems is established. The result partially generalizes even a classical limit
point criterion for the second order Sturm--Liouville difference equations.


title:
On discrete symplectic systems: Associated maximal and minimal linear
  relations and nonhomogeneous problems

abstract:
  In this paper we characterize the definiteness of the discrete symplectic
system, study a nonhomogeneous discrete symplectic system, and introduce the
minimal and maximal linear relations associated with these systems. Fundamental
properties of the corresponding deficiency indices, including a relationship
between the number of square summable solutions and the dimension of the defect
subspace, are also derived. Moreover, a sufficient condition for the existence
of a densely defined operator associated with the symplectic system is
provided.


title:
Noether symmetries and integrability in time-dependent Hamiltonian
  mechanics

abstract:
  We consider Noether symmetries within Hamiltonian setting as transformations
that preserve Poincar\'e-Cartan form, i.e., as symmetries of characteristic
line bundles of nondegenerate 1-forms. In the case when the Poincar\'e-Cartan
form is contact, the explicit expression for the symmetries in the inverse
Noether theorem is given. As examples, we consider natural mechanical systems,
in particular the Kepler problem. Finally, we prove a variant of the theorem on
complete (non-commutative) integrability in terms of Noether symmetries of
time-dependent Hamiltonian systems.


title: $SU(2)^2$-invariant $G_2$-instantons

abstract:
  We initiate the systematic study of $G_2$-instantons with $SU(2)^2$-symmetry.
As well as developing foundational theory, we give existence, non-existence and
classification results for these instantons. We particularly focus on
$\mathbb{R}^4\times S^3$ with its two explicitly known distinct holonomy $G_2$
metrics, which have different volume growths at infinity, exhibiting the
different behaviour of instantons in these settings. We also give an explicit
example of sequences of $G_2$-instantons where "bubbling" and "removable
singularity" phenomena occur in the limit.


title: Periodic motions generated from non-autonomous grazing dynamics

abstract:
  This paper examines impulsive non-autonomous systems with grazing periodic
solutions. Surfaces of discontinuity and impact functions of the systems are
not depending on the time variable. That is, we can say that the impact
conditions are stationary, and this makes necessity to study the problem in a
new way. The models play exceptionally important role in mechanics and
electronics. A concise review on the sufficient conditions for the new type of
linearization is presented. The existence and stability of periodic solutions
are considered under the circumstance of the regular perturbation. To visualize
the theoretical results, mechanical examples are presented.