title:
The formation of an inverse S-shaped active-region filament driven by
  sunspot motion and magnetic reconnection

abstract:
  We present a detailed study of the formation of an inverse S-shaped filament
prior to its eruption in active region NOAA 11884 from October 31 to November
2, 2013. In the initial stage, clockwise rotation of a small positive sunspot
around the main negative trailing sunspot formed a curved filament. Then the
small sunspot cancelled with negative magnetic flux to create a longer
active-region filament with an inverse S-shape. At the cancellation site a
brightening was observed in UV and EUV images and bright material was
transferred to the filament. Later the filament erupted after cancellation of
two opposite polarities under the upper part of the filament. Nonlinear
force-free field (NLFFF) extrapolation of vector photospheric fields suggests
that the filament may have a twisted structure, but this cannot be confirmed
from the current observations.


title:
Accurate X-Ray Absorption Predictions for Transition Metal Oxides: An
  Advanced Self-Consistent-Field Approach Inspired by Many-Body Perturbation
  Theory

abstract:
  Constrained-occupancy self-consistent-field ($\Delta$SCF) methods and
many-body perturbation theories (MBPT) are two strategies for obtaining
electronic excitations from first-principles. Using the two distinct
approaches, we study the O $1s$ core excitations that have become increasingly
important for characterizing transition metal oxides and developing theory of
strong correlations. Interestingly, we find that the $\Delta$SCF approach, in
its current single-particle form, systematically underestimates the pre-edge
intensity for chosen oxides, despite its success in weakly correlated systems.
By contrast, the Bethe-Salpeter equation within MBPT predicts much better
lineshapes. This inspires us to reexamine the many-electron dynamics of X-ray
excitations. We find that the single-particle $\Delta$SCF approach can be
rectified by explicitly calculating many-body transition amplitudes, producing
X-ray spectra in excellent agreement with experiments. Our study paves the way
to accurately predict X-ray near-edge spectral fingerprints for physics and
materials science beyond the Bethe-Salpether equation.


title: Distant Supervision for Relation Extraction beyond the Sentence Boundary

abstract:
  The growing demand for structured knowledge has led to great interest in
relation extraction, especially in cases with limited supervision. However,
existing distance supervision approaches only extract relations expressed in
single sentences. In general, cross-sentence relation extraction is
under-explored, even in the supervised-learning setting. In this paper, we
propose the first approach for applying distant supervision to cross- sentence
relation extraction. At the core of our approach is a graph representation that
can incorporate both standard dependencies and discourse relations, thus
providing a unifying way to model relations within and across sentences. We
extract features from multiple paths in this graph, increasing accuracy and
robustness when confronted with linguistic variation and analysis error.
Experiments on an important extraction task for precision medicine show that
our approach can learn an accurate cross-sentence extractor, using only a small
existing knowledge base and unlabeled text from biomedical research articles.
Compared to the existing distant supervision paradigm, our approach extracted
twice as many relations at similar precision, thus demonstrating the prevalence
of cross-sentence relations and the promise of our approach.


title: Finiteness of Homological Filling Functions

abstract:
  Let $G$ be a group. For any $\mathbb{Z} G$--module $M$ and any integer $d>0$,
we define a function $FV_{M}^{d+1}\colon \mathbb{N} \to \mathbb{N} \cup
\{\infty\}$ generalizing the notion of $(d+1)$--dimensional filling function of
a group. We prove that this function takes only finite values if $M$ is of type
$FP_{d+1}$ and $d>0$, and remark that the asymptotic growth class of this
function is an invariant of $M$. In the particular case that $G$ is a group of
type $FP_{d+1}$, our main result implies that its $(d+1)$-dimensional
homological filling function takes only finite values, addressing a question
from [12].


title:
Higgs bundles and indecomposable parabolic bundles over the projective
  line

abstract:
  In this paper we count the number of isomorphism classes of geometrically
indecomposable quasi-parabolic structures of a given type on a given vector
bundle on the projective line over a finite field. We give a conjectural
cohomological interpretation for this counting using the moduli space of Higgs
fields on the given vector bundle over the complex projective line with
prescribed residues. We prove a certain number of results which bring evidences
to the main conjecture. We detail the case of rank 2 vector bundles.


title:
Directional Searches at DUNE for Sub-GeV Monoenergetic Neutrinos Arising
  from Dark Matter Annihilation in the Sun

abstract:
  We consider the use of directionality in the search for monoenergetic sub-GeV
neutrinos arising from the decay of stopped kaons, which can be produced by
dark matter annihilation in the core of the Sun. When these neutrinos undergo
charged-current interactions with a nucleus at a neutrino detector, they often
eject a proton which is highly peaked in the forward direction. The direction
of this track can be measured at DUNE, allowing one to distinguish signal from
background by comparing on-source and off-source event rates. We find that
directional information can enhance the signal to background ratio by up to a
factor of 5.


title: $T$-Matrix Approach to Strongly Coupled QGP

abstract:
  Based on a thermodynamic $T$-matrix approach we extract the potential $V$
between two static charges in the quark-gluon plasma (QGP) from fits to the
pertinent lattice-QCD free energy. With suitable relativistic corrections we
utilize this new potential to compute heavy-quark transport coefficients and
compare the results to previous calculations using either $F$ or $U$ as
potential. We then discuss a generalization of the $T$-matrix re-summation to a
"matrix $\log$" re-summation of $t$-channel diagrams for the grand partition
function of the QGP in the Luttinger-Ward skeleton diagram formalism. With $V$
as a non-perturbative driving kernel in the light-parton sector, we obtain the
QGP equation of state from fits to lattice-QCD data. The resulting light-parton
spectral functions are characterized by large thermal widths at small momenta,
indicating the dissolution of quasi-particles in a strongly coupled QGP.


title: Can the Many-Worlds-Interpretation be probed in Psychology?

abstract:
  A minimal approach to the measurement problem and the quantum-to-classical
transition assumes a universally valid quantum formalism, i.e. unitary time
evolution governed by a Schr\"odinger-type equation. As had been pointed out
long ago, in this view the measurement process can be described by decoherence
which results in a "Many-Worlds" or "Many-Minds" scenario according to Everett
and Zeh. A silent assumption for decoherence to proceed is however, that there
exists incomplete information about the environment our object system gets
entangled with in the measurement process. This paper addresses the question
where this information is traced out and - by adopting recent approaches to
model consciousness in neuroscience - argues that a rigorous interpretation
results in a modern perspective on the von-Neumann-Wigner interpretation -
namely that the information that is or is not available in the consciousness of
the observer is crucial for the definition of the environment. As such the
quantum-to-classical transition while being difficult or impossible to probe in
physics may become testable in psychology.


title: NPCs as People, Too: The Extreme AI Personality Engine

abstract:
  PK Dick once asked "Do Androids Dream of Electric Sheep?" In video games, a
similar question could be asked of non-player characters: Do NPCs have dreams?
Can they live and change as humans do? Can NPCs have personalities, and can
these develop through interactions with players, other NPCs, and the world
around them? Despite advances in personality AI for games, most NPCs are still
undeveloped and undeveloping, reacting with flat affect and predictable
routines that make them far less than human--in fact, they become little more
than bits of the scenery that give out parcels of information. This need not be
the case. Extreme AI, a psychology-based personality engine, creates adaptive
NPC personalities. Originally developed as part of the thesis "NPCs as People:
Using Databases and Behaviour Trees to Give Non-Player Characters Personality,"
Extreme AI is now a fully functioning personality engine using all thirty
facets of the Five Factor model of personality and an AI system that is live
throughout gameplay. This paper discusses the research leading to Extreme AI;
develops the ideas found in that thesis; discusses the development of other
personality engines; and provides examples of Extreme AI's use in two game
demos.


title: Die-out Probability in SIS Epidemic Processes on Networks

abstract:
  An accurate approximate formula of the die-out probability in a SIS epidemic
process on a network is proposed. The formula contains only three essential
parameters: the largest eigenvalue of the adjacency matrix of the network, the
effective infection rate of the virus, and the initial number of infected nodes
in the network. The die-out probability formula is compared with the exact
die-out probability in complete graphs, Erd\H{o}s-R\'enyi graphs, and a
power-law graph. Furthermore, as an example, the formula is applied to the
$N$-Intertwined Mean-Field Approximation, to explicitly incorporate the
die-out.


title:
Analytical Solutions for Bending Of Fireworks and Similarities with the
  Solution of Electromagnetic Wave Diffraction

abstract:
  In this paper we examine more deeply about the bending mechanism of
rod-shaped fireworks which burned from the free end. We derived new analytic
equations. Surprisingly, we obtained the bending patterns are similar to the
cornu spiral. With a few simple steps we proved that positions of points
throughout the fireworks are given by Fresnel integrals, C(x) and S(x), which
are generally found in phenomena of electromagnetic wave diffraction. Although
we deeply discussed bending of fireworks rods, however the proposed method is
likely to explain any phenomena in nature related to an evolving length scale
associated with some material that becomes progressively stiff or dry, such as
the growth of resin exuded from trees.


title: A Revised Collection of Sunspot Group Numbers

abstract:
  We describe a revised collection of the number of sunspot groups from 1610 to
the present. This new collection is based on the work of Hoyt and Schatten
(Solar Phys. 179, 189, 1998). The main changes are the elimination of a
considerable number of observations during the Maunder Minimum (hereafter, MM)
and the inclusion of several long series of observations. Numerous minor
changes are also described. Moreover, we have calculated the active-day
percentage during the MM from this new collection as a reliable index of the
solar activity. Thus, the level of solar activity obtained in this work is
greater than the level obtained using the original Hoyt and Schatten data,
although it remains compatible with a grand minimum of solar activity. The new
collection is available in digital format.


title:
On-diagonal Heat Kernel Lower Bound for Strongly Local Symmetric
  Dirichlet Forms

abstract:
  This paper studies strongly local symmetric Dirichlet forms on general
measure spaces. The underlying space is equipped with the intrinsic metric
induced by the Dirichlet form, with respect to which the metric measure space
does not necessarily satisfy volume-doubling property. Assuming Nash-type
inequality, it is proved in this paper that outside a properly exceptional set,
given a pointwise on-diagonal heat kernel upper bound in terms of the volume
function, the comparable heat kernel lower bound also holds. The only
assumption made on the volume growth rate is that it can be bounded by a
continuous function satisfying doubling property, in other words, is not
exponential.


title: Operators with compatible ranges

abstract:
  A bounded operator $T$ on a finite or infinite--dimensional Hilbert space is
called a disjoint range (DR) operator if $R(T)\cap R(T^*)=\{0\}$, where $T^*$
stands for the adjoint of $T$, while $R(\cdot)$ denotes the range of an
operator. Such operators (matrices) were introduced and systematically studied
by Baksalary and Trenkler, and later by Deng et al. In this paper we introduce
a wider class of operators: we say that $T$ is a compatible range (CoR)
operator if $T$ and $T^*$ coincide on $R(T)\cap R(T^*)$. We extend and improve
some results about DR operators and derive some new results regarding the CoR
class.


title: Almost global consensus on the n-sphere

abstract:
  This paper establishes novel results regarding the global convergence
properties of a large class of consensus protocols for multi-agent systems that
evolve in continuous time on the n-dimensional unit sphere or n-sphere. For any
connected, undirected graph and all n in N\{1}, each protocol in said class is
shown to yield almost global consensus. The feedback laws are negative
gradients of Lyapunov functions and one instance generates the canonical
intrinsic gradient descent protocol. This convergence result sheds new light on
the general problem of consensus on Riemannian manifolds; the n-sphere for n in
N\{1} differs from the circle and SO(3) where the corresponding protocols fail
to generate almost global consensus. Moreover, we derive a novel consensus
protocol on SO(3) by combining two almost globally convergent protocols on the
n-sphere for n in {1,2}. Theoretical and simulation results suggest that the
combined protocol yields almost global consensus on SO(3).


title:
Are Delayed Issues Harder to Resolve? Revisiting Cost-to-Fix of Defects
  throughout the Lifecycle

abstract:
  Many practitioners and academics believe in a delayed issue effect (DIE);
i.e. the longer an issue lingers in the system, the more effort it requires to
resolve. This belief is often used to justify major investments in new
development processes that promise to retire more issues sooner.
  This paper tests for the delayed issue effect in 171 software projects
conducted around the world in the period from 2006--2014. To the best of our
knowledge, this is the largest study yet published on this effect. We found no
evidence for the delayed issue effect; i.e. the effort to resolve issues in a
later phase was not consistently or substantially greater than when issues were
resolved soon after their introduction.
  This paper documents the above study and explores reasons for this mismatch
between this common rule of thumb and empirical data. In summary, DIE is not
some constant across all projects. Rather, DIE might be an historical relic
that occurs intermittently only in certain kinds of projects. This is a
significant result since it predicts that new development processes that
promise to faster retire more issues will not have a guaranteed return on
investment (depending on the context where applied), and that a long-held truth
in software engineering should not be considered a global truism.


title: On higher Chern classes of vector bundles of conformal blocks

abstract:
  Here we consider higher Chern classes of vector bundles of conformal blocks
on $\overline{\operatorname{M}}_{0,n}$, giving explicit formulas for them, and
extending various results that hold for first Chern classes to them. We use
these classes to form a full dimensional subcone of the Pliant cone on
$\overline{\operatorname{M}}_{0,n}$.


title: Resource-Performance Trade-off Analysis for Mobile Robot Design

abstract:
  The design of mobile autonomous robots is challenging due to the limited
on-board resources such as processing power and energy. A promising approach is
to generate intelligent schedules that reduce the resource consumption while
maintaining best performance, or more interestingly, to trade off reduced
resource consumption for a slightly lower but still acceptable level of
performance. In this paper, we provide a framework to aid designers in
exploring such resource-performance trade-offs and finding schedules for mobile
robots, guided by questions such as "what is the minimum resource budget
required to achieve a given level of performance?" The framework is based on a
quantitative multi-objective verification technique which, for a collection of
possibly conflicting objectives, produces the Pareto front that contains all
the optimal trade-offs that are achievable. The designer then selects a
specific Pareto point based on the resource constraints and desired performance
level, and a correct-by-construction schedule that meets those constraints is
automatically generated. We demonstrate the efficacy of this framework on
several robotic scenarios in both simulations and experiments with encouraging
results.


title: Theorems of B\^ocher's type for dynamic equations on time scales

abstract:
  The conditions are found that all solutions of a systems dynamic equations on
time scales tends to finite limits as $t\to\infty$.


title:
Microscopic Understanding of Cross-Responses between Stocks: a
  Two-Component Price Impact Model

abstract:
  We construct a price impact model between stocks in a correlated market. For
the price change of a given stock induced by the short-run liquidity of this
stock itself and of the information about other stocks, we introduce a self-
and a cross-impact function of the time lag. We model the average
cross-response functions for individual stocks employing the impact functions
of the time lag, the impact functions of traded volumes and the trade-sign
correlators. To quantify the self- and cross-impacts, we propose a construction
to fix the parameters in the impact functions. These parameters are further
corroborated by a diffusion function that measures the correlated motion of
prices from different stocks. This construction is mainly ad hoc and
alternative ones are not excluded. It turns out that both the sign cross- and
self-correlators are connected with the cross-responses. The self- and
cross-impact functions are indispensable to compensate amplification effects
which are due to the sign correlators integrated over time. We further quantify
and interpret the price impacts of time lag in terms of temporary and permanent
components. To support our model, we also analyze empirical data, in particular
the memory properties of the sign self- and average cross-correlators. The
relation between the average cross-responses and the traded volumes which are
smaller than their average is of power-law form.


title: On Wirelessly Powered Communications with Short Packets

abstract:
  Wireless-powered communications will entail short packets due to naturally
small payloads, low latency requirements and/or insufficient energy resources
to support longer transmissions. In this paper, a wireless-powered
communication system is investigated where an energy harvesting transmitter,
charged by a power beacon via wireless energy transfer, attempts to communicate
with a receiver over a noisy channel. Leveraging the framework of finite-length
information theory, the system performance is analyzed using metrics such as
the energy supply probability at the transmitter, and the achievable rate at
the receiver. The analysis yields useful insights into the system behavior in
terms of key parameters such as the harvest blocklength, the transmit
blocklength, the average harvested power and the transmit power. Closed-form
expressions are derived for the asymptotically optimal transmit power.
Numerical results suggest that power control is essential for improving the
achievable rate of the system in the finite blocklength regime.


title: Cubic Planar Graphs and Legendrian Surface Theory

abstract:
  We study Legendrian surfaces determined by cubic planar graphs. Graphs with
distinct chromatic polynomials determine surfaces that are not Legendrian
isotopic, thus giving many examples of non-isotopic Legendrian surfaces with
the same classical invariants. The Legendrians have no exact Lagrangian
fillings, but have many interesting non-exact fillings.
  We obtain these results by studying sheaves on a three-ball with microsupport
in the surface. The moduli of such sheaves has a concrete description in terms
of the graph and a beautiful embedding as a holomorphic Lagrangian submanifold
of a symplectic period domain, a Lagrangian that has appeared in the work of
Dimofte-Gabella-Goncharov [DGGo]. We exploit this structure to find conjectural
open Gromov-Witten invariants for the non-exact filling, following
Aganagic-Vafa [AV, AV2].


title:
SN1991bg-like supernovae are a compelling source of most Galactic
  antimatter

abstract:
  The Milky Way Galaxy glows with the soft gamma ray emission resulting from
the annihilation of $\sim 5 \times 10^{43}$ electron-positron pairs every
second. The origin of this vast quantity of antimatter and the peculiar
morphology of the 511keV gamma ray line resulting from this annihilation have
been the subject of debate for almost half a century. Most obvious positron
sources are associated with star forming regions and cannot explain the rate of
positron annihilation in the Galactic bulge, which last saw star formation some
$10\,\mathrm{Gyr}$ ago, or else violate stringent constraints on the positron
injection energy. Radioactive decay of elements formed in core collapse
supernovae (CCSNe) and normal Type Ia supernovae (SNe Ia) could supply
positrons matching the injection energy constraints but the distribution of
such potential sources does not replicate the required morphology. We show that
a single class of peculiar thermonuclear supernova - SN1991bg-like supernovae
(SNe 91bg) - can supply the number and distribution of positrons we see
annihilating in the Galaxy through the decay of $^{44}$Ti synthesised in these
events. Such $^{44}$Ti production simultaneously addresses the observed
abundance of $^{44}$Ca, the $^{44}$Ti decay product, in solar system material.


title:
Giant anisotropic nonlinear optical response in transition metal
  monopnictide Weyl semimetals

abstract:
  Although Weyl fermions have proven elusive in high-energy physics, their
existence as emergent quasiparticles has been predicted in certain crystalline
solids in which either inversion or time-reversal symmetry is
broken\cite{WanPRB2011,BurkovPRL2011, WengPRX2015,HuangNatComm2015}. Recently
they have been observed in transition metal monopnictides (TMMPs) such as TaAs,
a class of noncentrosymmetric materials that heretofore received only limited
attention \cite{XuScience2015, LvPRX2015, YangNatPhys2015}. The question that
arises now is whether these materials will exhibit novel, enhanced, or
technologically applicable electronic properties. The TMMPs are polar metals, a
rare subset of inversion-breaking crystals that would allow spontaneous
polarization, were it not screened by conduction electrons
\cite{anderson1965symmetry,shi2013ferroelectric,kim2016polar}. Despite the
absence of spontaneous polarization, polar metals can exhibit other signatures
of inversion-symmetry breaking, most notably second-order nonlinear optical
polarizability, $\chi^{(2)}$, leading to phenomena such as optical
rectification and second-harmonic generation (SHG). Here we report measurements
of SHG that reveal a giant, anisotropic $\chi^{(2)}$ in the TMMPs TaAs, TaP,
and NbAs. With the fundamental and second harmonic fields oriented parallel to
the polar axis, the value of $\chi^{(2)}$ is larger by almost one order of
magnitude than its value in the archetypal electro-optic materials GaAs
\cite{bergfeld2003second} and ZnTe \cite{wagner1998dispersion}, and in fact
larger than reported in any crystal to date.


title: Fields of moduli of classical Humbert curves

abstract:
  The computation of the field of moduli of a closed Riemann surface seems to
be a very difficult problem and even more difficult is to determine if the
field of moduli is a field of definition. In this paper we consider the family
of closed Riemann surfaces of genus five admitting a group of conformal
automorphisms isomorphic to ${\mathbb Z}_{2}^{4}$. These surfaces are
non-hyperelliptic ones and turn out to be the highest branched abelian covers
of the orbifolds of genus zero and five cone points of order two. We compute
the field of moduli of these surfaces and we prove that they are fields of
definition. This result is in contrast with the case of the highest branched
abelian covers of the orbifolds of genus zero and six cone points of order two
as there are cases for which the above property fails.


title: Modular Categories of Dimension $p^3m$ with $m$ Square-Free

abstract:
  We give a complete classification of modular categories of dimension $p^3m$
where $p$ is prime and $m$ is a square-free integer. When $p$ is odd, all such
categories are pointed. For $p=2$ one encounters modular categories with the
same fusion ring as orthogonal quantum groups at certain roots of unity, namely
$SO(2m)_2$. As an immediate step we classify a more general class of so-called
even metaplectic modular categories with the same fusion rules as $SO(2N)_2$
with $N$ odd.


title: Variants of the Entropy Power Inequality

abstract:
  An extension of the entropy power inequality to the form $N_r^\alpha(X+Y)
\geq N_r^\alpha(X) + N_r^\alpha(Y)$ with arbitrary independent summands $X$ and
$Y$ in $\mathbb{R}^n$ is obtained for the R\'enyi entropy and powers $\alpha
\geq (r+1)/2$.


title: Field of moduli of generalized Fermat curves

abstract:
  As a consequence of the Riemann-Roch theorem, a closed Riemann surface $S$
can be described by a non-singular complex projective algebraic curve $C$. A
field of definition for $S$ is any subfield $D$ of $\mathbb{C}$ so that we may
choose $C$ to be defined by polynomials in $D[x_0, \ldots, x_n]$. The field of
moduli of $S$ is ${\mathbb R}$ if and only if $S$ admits an anticonformal
automorphism. In the case that the field of moduli of $S$ is ${\mathbb R}$,
then $S$ can be defined over the field of moduli if and only if $S$ admits an
anticonformal involution. It may happen that the field of moduli is not a field
of definition.
  In this paper, we consider certain class of closed Riemann surfaces, called
generalized Fermat curves. These surfaces are the highest Abelian branched
cover of certain orbifolds. In this class of Riemann surfaces, we study the
problem of deciding when the field of moduli is ${\mathbb R}$ and when, in such
a case, it is a field of definition.


title: Associative and Jordan algebras generated by two idempotents

abstract:
  Associative or Jordan algebras generated by two idempotents are described
precisely.


title:
A topological lower bound for the energy of a unit vector field on a
  closed hypersurface of the euclidean space. The 3-dimensional case

abstract:
  In this short note we prove that the degree of the Gauss map {\nu} of a
closed 3-dimensional hypersurface of the Euclidean space is a lower bound for
the total bending functional B, introduced by G. Wiegmink. Consequently, the
energy functional E introduced by C. M. Wood admits a topological lower bound.


title: Strangeness in STAR at RHIC

abstract:
  We present the recent results of strangeness production at the mid-rapidity
in Au + Au collisions at RHIC, from $\sqrt{s_{\rm NN}}$ = 7.7 to 200 GeV. The
$v_2$ of multi-strange baryon $\Omega$ and $\phi$ mesons are similar to that of
pions and protons in the intermediate $p_T$ range (2 - 5 GeV/$c$) in
$\sqrt{s_{\rm NN}}$ = 200 GeV Au + Au collisions, indicating that the major
part of collective flow has been built up at partonic stage. The breaking of
mass ordering between $\phi$ mesons and protons in the low $p_T$ range ($<$ 1
GeV/$c$) is consistent with a picture that $\phi$ mesons are less sensitive to
later hadronic interaction. The nuclear modification factor $R_{\rm CP}$ and
baryon to meson ratio change dramatically when the collision energy is lower
than 19.6 GeV. It suggests a possible change of medium property of the system
compared to those from high energies.


title:
A Quadratically Regularized Functional Canonical Correlation Analysis
  for Identifying the Global Structure of Pleiotropy with NGS Data

abstract:
  Investigating the pleiotropic effects of genetic variants can increase
statistical power, provide important information to achieve deep understanding
of the complex genetic structures of disease, and offer powerful tools for
designing effective treatments with fewer side effects. However, the current
multiple phenotype association analysis paradigm lacks breadth (number of
phenotypes and genetic variants jointly analyzed at the same time) and depth
(hierarchical structure of phenotype and genotypes). A key issue for high
dimensional pleiotropic analysis is to effectively extract informative internal
representation and features from high dimensional genotype and phenotype data.
To explore multiple levels of representations of genetic variants, learn their
internal patterns involved in the disease development, and overcome critical
barriers in advancing the development of novel statistical methods and
computational algorithms for genetic pleiotropic analysis, we proposed a new
framework referred to as a quadratically regularized functional CCA (QRFCCA)
for association analysis which combines three approaches: (1) quadratically
regularized matrix factorization, (2) functional data analysis and (3)
canonical correlation analysis (CCA). Large-scale simulations show that the
QRFCCA has a much higher power than that of the nine competing statistics while
retaining the appropriate type 1 errors. To further evaluate performance, the
QRFCCA and nine other statistics are applied to the whole genome sequencing
dataset from the TwinsUK study. We identify a total of 79 genes with rare
variants and 67 genes with common variants significantly associated with the 46
traits using QRFCCA. The results show that the QRFCCA substantially outperforms
the nine other statistics.


title:
Ensemble-Based Algorithms to Detect Disjoint and Overlapping Communities
  in Networks

abstract:
  Given a set ${\cal AL}$ of community detection algorithms and a graph $G$ as
inputs, we propose two ensemble methods $\mathtt{EnDisCO}$ and $\mathtt{MeDOC}$
that (respectively) identify disjoint and overlapping communities in $G$.
$\mathtt{EnDisCO}$ transforms a graph into a latent feature space by leveraging
multiple base solutions and discovers disjoint community structure.
$\mathtt{MeDOC}$ groups similar base communities into a meta-community and
detects both disjoint and overlapping community structures. Experiments are
conducted at different scales on both synthetically generated networks as well
as on several real-world networks for which the underlying ground-truth
community structure is available. Our extensive experiments show that both
algorithms outperform state-of-the-art non-ensemble algorithms by a significant
margin. Moreover, we compare $\mathtt{EnDisCO}$ and $\mathtt{MeDOC}$ with a
recent ensemble method for disjoint community detection and show that our
approaches achieve superior performance. To the best of our knowledge,
$\mathtt{MeDOC}$ is the first ensemble approach for overlapping community
detection.


title: Long-Term Trends in the Public Perception of Artificial Intelligence

abstract:
  Analyses of text corpora over time can reveal trends in beliefs, interest,
and sentiment about a topic. We focus on views expressed about artificial
intelligence (AI) in the New York Times over a 30-year period. General
interest, awareness, and discussion about AI has waxed and waned since the
field was founded in 1956. We present a set of measures that captures levels of
engagement, measures of pessimism and optimism, the prevalence of specific
hopes and concerns, and topics that are linked to discussions about AI over
decades. We find that discussion of AI has increased sharply since 2009, and
that these discussions have been consistently more optimistic than pessimistic.
However, when we examine specific concerns, we find that worries of loss of
control of AI, ethical concerns for AI, and the negative impact of AI on work
have grown in recent years. We also find that hopes for AI in healthcare and
education have increased over time.


title: Accelerated gradient sliding for structured convex optimization

abstract:
  Our main goal in this paper is to show that one can skip gradient
computations for gradient descent type methods applied to certain structured
convex programming (CP) problems. To this end, we first present an accelerated
gradient sliding (AGS) method for minimizing the summation of two smooth convex
functions with different Lipschitz constants. We show that the AGS method can
skip the gradient computation for one of these smooth components without
slowing down the overall optimal rate of convergence. This result is much
sharper than the classic black-box CP complexity results especially when the
difference between the two Lipschitz constants associated with these components
is large. We then consider an important class of bilinear saddle point problem
whose objective function is given by the summation of a smooth component and a
nonsmooth one with a bilinear saddle point structure. Using the aforementioned
AGS method for smooth composite optimization and Nesterov's smoothing
technique, we show that one only needs ${\cal O}(1/\sqrt{\epsilon})$ gradient
computations for the smooth component while still preserving the optimal ${\cal
O}(1/\epsilon)$ overall iteration complexity for solving these saddle point
problems. We demonstrate that even more significant savings on gradient
computations can be obtained for strongly convex smooth and bilinear saddle
point problems.


title: Itinerant routing in elastic optical networks

abstract:
  We state a new problem of \emph{itinerant routing} in elastic optical
networks, which we define as the establishment and reconfiguration of an
\emph{itinerant connection}. In an itinerant connection, one of the connection
end nodes is allowed to change. Itinerant routing could also be considered a
form of connection restoration, where a connection has to be restored to a
different end node. With the introduction of new mobile-network architectures,
the progressing integration of wireless and optical networks, the continuing
growth of wireless high-bitrate services, and the eventual deployment of
elastic optical networks, there is a need to support this itinerant routing in
the elastic optical networks. We present and discuss two major use cases of the
itinerant routing, and propose a \emph{novel reconfiguration algorithm}. Our
algorithm does not deteriorate the network performance, and requires half as
many new links to configure as the shortest-path reconfiguration algorithm. The
performance evaluation was carried out with 46800 simulation runs using
randomly-generated realistic transport networks.


title:
Asset Pricing in a Semi-Markov Modulated Market with Time-dependent
  Volatility

abstract:
  This project attempts to address the problem of asset pricing in a financial
market, where the interest rates and volatilities exhibit regime switching.
This is an extension of the Black-Scholes model. Studies of Markov-modulated
regime switching models have been well-documented. This project extends that
notion to a class of semi-Markov processes known as age-dependent processes. We
also allow for time-dependence in volatility within regimes. We show that the
problem of option pricing in such a market is equivalent to solving a certain
integral equation.


title:
Heavy flavor production in heavy-ion collisions from soft collinear
  effective theory

abstract:
  We review a new approach to open heavy flavor production in heavy ion
collisions based on Soft Collinear Effective Theory (SCET). We include both
finite heavy quark masses in the SCET Lagrangian and Glauber gluons that
describe the interaction of collinear partons with the hot and dense QCD
medium. From the new effective field theory, we derive massive in-medium
splitting kernels and propose a new framework for including in-medium
interactions consistent with next-to-leading order calculations in QCD. We
present numerical results for the suppression of $D$- and $B$-mesons and
compare to results obtained within the traditional approach to parton energy
loss. We find good agreement when comparing to existing data from the LHC at
$\sqrt{s_{\mathrm{NN}}}=5.02$ TeV and 2.76 TeV.


title:
An Iterative Transfer Learning Based Ensemble Technique for Automatic
  Short Answer Grading

abstract:
  Automatic short answer grading (ASAG) techniques are designed to
automatically assess short answers to questions in natural language, having a
length of a few words to a few sentences. Supervised ASAG techniques have been
demonstrated to be effective but suffer from a couple of key practical
limitations. They are greatly reliant on instructor provided model answers and
need labeled training data in the form of graded student answers for every
assessment task. To overcome these, in this paper, we introduce an ASAG
technique with two novel features. We propose an iterative technique on an
ensemble of (a) a text classifier of student answers and (b) a classifier using
numeric features derived from various similarity measures with respect to model
answers. Second, we employ canonical correlation analysis based transfer
learning on a common feature representation to build the classifier ensemble
for questions having no labelled data. The proposed technique handsomely beats
all winning supervised entries on the SCIENTSBANK dataset from the Student
Response Analysis task of SemEval 2013. Additionally, we demonstrate
generalizability and benefits of the proposed technique through evaluation on
multiple ASAG datasets from different subject topics and standards.


title:
Strong laws of large numbers for intermediately trimmed sums of i.i.d.
  random variables with infinite mean

abstract:
  We consider moderately trimmed sums of non-negative i.i.d. random variables.
We show that for every distribution function there exists a proper moderate
trimming such that for the trimmed sum a non-trivial strong law of large
numbers holds. In case that the distribution function has regularly varying
tails we give necessary and sufficient conditions on the trimming for a strong
law of large numbers to hold.


title: The quark mean field model with pion and gluon corrections

abstract:
  The properties of nuclear matter and finite nuclei are studied within the
quark mean field (QMF) model by taking the effects of pion and gluon into
account at the quark level. The nucleon is described as the combination of
three constituent quarks confined by a harmonic oscillator potential. To
satisfy the spirit of QCD theory, the contributions of pion and gluon on the
nucleon structure are treated in second-order perturbation theory. For the
nuclear many-body system, nucleons interact with each other by exchanging
mesons between quarks. With different constituent quark mass, $m_q$, we
determine three parameter sets about the coupling constants between mesons and
quarks, named as QMF-NK1, QMF-NK2, and QMF-NK3 by fitting the ground-state
properties of several closed-shell nuclei. It is found that all of the three
parameter sets can give satisfactory description on properties of nuclear
matter and finite nuclei, meanwhile they can also predict the larger neutron
star mass around $2.3M_\odot$ without the hyperon degrees of freedom.


title: Scarring of quasimodes on hyperbolic manifolds

abstract:
  Let $N$ be a compact hyperbolic manifold, $M\subset N$ an embedded totally
geodesic submanifold, and let $-\hbar^2\Delta_{N}$ be the semiclassical
Laplace--Beltrami operator.
  For any $\varepsilon>0$, we explicitly construct families of
\emph{quasimodes} of spectral width at most
$\varepsilon\frac{\hbar}{|\log\hbar|}$ which exhibit a "strong scar" on $M$ in
that their microlocal lifts converge weakly to a probability measure which
places positive weight on $S^*M$ ($\hookrightarrow S^*N$). An immediate
corollary is that \emph{any} invariant measure on $S^*N$ occurs in the ergodic
decomposition of the semiclassical limit of certain quasimodes of width
$\varepsilon \frac{\hbar}{|\log\hbar|}$


title:
Design of an Optoelectronic State Machine with integrated BDD based
  Optical logic

abstract:
  In this paper I demonstrate a novel design for an optoelectronic State
Machine which replaces input/output forming logic found in conventional state
machines with BDD based optical logic while still using solid state memory in
the form of flip-flops in order to store states. This type of logic makes use
of waveguides and ring resonators to create binary switches. These switches in
turn can be used to create combinational logic which can be used as
input/output forming logic for a state machine. Replacing conventional
combinational logic with BDD based optical logic allows for a faster range of
state machines that can certainly outperform conventional state machines as
propagation delays within the logic described are in the order of picoseconds
as opposed to nanoseconds in digital logic.


title: Nature of low-lying electric dipole resonance excitations in 74Ge

abstract:
  Isospin properties of dipole excitations in 74 Ge are investigated using the
({\alpha},{\alpha}'{\gamma}) reaction and compared to ({\gamma},{\gamma}) data.
The results indicate that the dipole excitations in the energy region of 6 to 9
MeV adhere to the scenario of the recently found splitting of the region of
dipole excitations into two separated parts: one at low energy, being populated
by both isoscalar and isovector probes, and the other at high energy, excited
only by the electromagnetic probe. Relativistic quasiparticle time blocking
approximation (RQTBA) calculations show a reduction in the isoscalar E1
strength with an increase in excitation energy, which is consistent with the
measurement.


title: HR8844: A new hot Am star ?

abstract:
  Using one archival high dispersion high quality spectrum of HR8844 (A0V)
obtained with the echelle spectrograph SOPHIE at Observatoire de Haute
Provence, we show that this star is not a superficially normal A0V star as
hitherto thought. The model atmosphere and spectrum synthesis modeling of the
spectrum of HR8844 reveals large departures of its abundances from the solar
composition. We report here on our first determinations of the elemental
abundances of 41 elements in the atmosphere of HR8844. Most of the light
elements are underabundant whereas the very heavy elements are overabundant in
HR8844.This interesting new chemically peculiar star could be a hybrid object
between the HgMn stars and the Am stars.


title:
On the RR Lyrae stars in globulars: IV. $\omega$ Centauri Optical UBVRI
  Photometry

abstract:
  New accurate and homogeneous optical UBVRI photometry has been obtained for
variable stars in the Galactic globular $\omega$ Cen (NGC 5139). We secured
8202 CCD images covering a time interval of 24 years and a sky area of 84x48
arcmin. The current data were complemented with data available in the
literature and provided new, homogeneous pulsation parameters (mean magnitudes,
luminosity amplitudes,periods) for 187 candidate $\omega$ Cen RR Lyrae (RRLs).
Among them we have 101 RRc (first overtone), 85 RRab (fundamental) and a single
candidate RRd (double-mode) variables. Candidate Blazhko RRLs show periods and
colors that are intermediate between RRc and RRab variables, suggesting that
they are transitional objects.
  The comparison of the period distribution and of the Bailey diagram indicates
that RRLs in $\omega$ Cen show a long-period tail not present in typical
Oosterhoff II (OoII) globulars. The RRLs in dwarf spheroidals and in ultra
faint dwarfs have properties between Oosterhoff intermediate and OoII clusters.
Metallicity plays a key role in shaping the above evidence. These findings do
not support the hypothesis that $\omega$ Cen is the core remnant of a spoiled
dwarf galaxy.
  Using optical Period-Wesenheit relations that are reddening-free and
minimally dependent on metallicity we find a mean distance to $\omega$ Cen of
13.71$\pm$0.08$\pm$0.01 mag (semi-empirical and theoretical calibrations).
Finally, we invert the I-band Period-Luminosity-Metallicity relation to
estimate individual RRLs metal abundances. The metallicity distribution agrees
quite well with spectroscopic and photometric metallicity estimates available
in the literature.


title: Theory overview of Heavy Ion collisions

abstract:
  This presentation discusses some recently active topics in the theoretical
interpretation of high energy heavy ion collisions at the LHC and at RHIC. We
argue that the standard paradigm for understanding the spacetime evolution of
the bulk of the matter produced in the collision is provided by viscous
relativistic hydrodynamics, which can be used to systematically extract
properties of the QCD medium from experimental results. The initial conditions
of this hydrodynamical evolution are increasingly well understood in terms of
gluon saturation, and can be quantified using Classical Yang-Mills fields and
QCD effective kinetic theory. Hard and electromagnetic probes of the plasma
provide additional constraints. A particularly fascinating subject are high
multiplicity proton-proton and proton-nucleus collisions, where some of the
characteristics previously attributed to only nucleus-nucleus collisions have
been observed.


title: Steiner Network Problems on Temporal Graphs

abstract:
  We introduce a temporal Steiner network problem in which a graph, as well as
changes to its edges and/or vertices over a set of discrete times, are given as
input; the goal is to find a minimal subgraph satisfying a set of $k$
time-sensitive connectivity demands. We show that this problem, $k$-Temporal
Steiner Network ($k$-TSN), is NP-hard to approximate to a factor of $k -
\epsilon$, for every fixed $k \geq 2$ and $\epsilon > 0$. This bound is tight,
as certified by a trivial approximation algorithm. Conceptually this
demonstrates, in contrast to known results for traditional Steiner problems,
that a time dimension adds considerable complexity even when the problem is
offline.
  We also discuss special cases of $k$-TSN in which the graph changes satisfy a
monotonicity property. We show approximation-preserving reductions from
monotonic $k$-TSN to well-studied problems such as Priority Steiner Tree and
Directed Steiner Tree, implying improved approximation algorithms.
  Lastly, $k$-TSN and its variants arise naturally in computational biology; to
facilitate such applications, we devise an integer linear program for $k$-TSN
based on network flows.


title: Voltage Controlled Memristor Threshold Logic Gates

abstract:
  In this paper, we present a resistive switching memristor cell for
implementing universal logic gates. The cell has a weighted control input whose
resistance is set based on a control signal that generalizes the operational
regime from NAND to NOR functionality. We further show how threshold logic in
the voltage-controlled resistive cell can be used to implement a XOR logic.
Building on the same principle we implement a half adder and a 4-bit CLA (Carry
Look-ahead Adder) and show that in comparison with CMOS-only logic, the
proposed system shows significant improvements in terms of device area, power
dissipation and leakage power.


title:
The Void Galaxy Survey: Photometry, structure and identity of void
  galaxies

abstract:
  We analyze photometry from deep B-band images of 59 void galaxies in the Void
Galaxy Survey (VGS), together with their near-infrared 3.6$\mu$m and 4.5$\mu$m
Spitzer photometry. The VGS galaxies constitute a sample of void galaxies that
were selected by a geometric-topological procedure from the SDSS DR7 data
release, and which populate the deep interior of voids. Our void galaxies span
a range of absolute B-magnitude from $\rm{M_B=-15.5}$ to $\rm{M_B=-20}$, while
at the 3.6$\mu$m band their magnitudes range from $\rm{M_{3.6}=-18}$ to
$\rm{M_{3.6}=-24}$. Their B-[3.6] colour and structural parameters indicate
these are star forming galaxies. A good reflection of the old stellar
population, the near-infrared band photometry also provide a robust estimate of
the stellar mass, which for the VGS galaxies we confirm to be smaller than $3
\times 10^{10}$ M$_\odot$. In terms of the structural parameters and
morphology, our findings align with other studies in that our VGS galaxy sample
consists mostly of small late-type galaxies. Most of them are similar to Sd-Sm
galaxies, although a few are irregularly shaped galaxies. The sample even
includes two early-type galaxies, one of which is an AGN. Their S\'{e}rsic
indices are nearly all smaller than $n=2$ in both bands and they also have
small half-light radii. In all, we conclude that the principal impact of the
void environment on the galaxies populating them mostly concerns their low
stellar mass and small size.


title: CMOS-Memristor Dendrite Threshold Circuits

abstract:
  Non-linear neuron models overcomes the limitations of linear binary models of
neurons that have the inability to compute linearly non-separable functions
such as XOR. While several biologically plausible models based on dendrite
thresholds are reported in the previous studies, the hardware implementation of
such non-linear neuron models remain as an open problem. In this paper, we
propose a circuit design for implementing logical dendrite non-linearity
response of dendrite spike and saturation types. The proposed dendrite cells
are used to build XOR circuit and intensity detection circuit that consists of
different combinations of dendrite cells with saturating and spiking responses.
The dendrite cells are designed using a set of memristors, Zener diodes, and
CMOS NOT gates. The circuits are designed, analyzed and verified on circuit
boards.


title:
Optically assisted trapping with high-permittivity dielectric rings:
  Towards optical aerosol filtration

abstract:
  Controlling the transport, trapping, and filtering of nanoparticles is
important for many applications. By virtue of their weak response to gravity
and their thermal motion, various physical mechanisms can be exploited for such
operations on nanoparticles. However, the manipulation based on optical forces
is potentially most appealing since it constitutes a highly deterministic
approach. Plasmonic nanostructures have been suggested for this purpose, but
they possess the disadvantages of locally generating heat and trapping the
nanoparticles directly on surface. Here, we propose the use of dielectric rings
made of high permittivity materials for trapping nanoparticles. Thanks to their
ability to strongly localize the field in space, nanoparticles can be trapped
without contact. We use a semi-analytical method to study the ability of these
rings to trap nanoparticles. Results are supported by full-wave simulations.
Application of the trapping concept to nanoparticle filtration is suggested.


title: Explicit evaluation of quadratic Euler sums

abstract:
  In this paper, we work out some explicit formulae for double nonlinear Euler
sums involving harmonic numbers and alternating harmonic numbers. As
applications of these formulae, we give new closed form representations of
several quadratic Euler sums through Riemann zeta function and linear sums. The
given representations are new.


title: On harmonic numbers and nonlinear Euler sums

abstract:
  In this paper we are interested in Euler-type sums with products of harmonic
numbers, Stirling numbers and Bell numbers. We discuss the analytic
representations of Euler sums through values of polylogarithm function and
Riemann zeta function. Moreover, we provide explicit evaluations for almost all
Euler sums with weight 5, which can be expressed in terms of zeta values and
polylogarithms. Furthermore, we give explicit formula for several classes of
Euler-related sums in terms of zeta values and harmonic numbers, and several
examples are given. The given representations are new.


title:
Generation of antitropic electron beams by self-generated electric
  field. Kinetic description

abstract:
  This paper makes use of a one-dimensional kinetic model to investigate the
nonlinear longitudinal dynamics of electron beams generated in the plasma under
the influence of a self-generated electric field. It is expressed as where is a
wave potential, , and charge particle distribution functions satisfy the Vlasov
equation. It is proved that its correct solution is characterized by sudden
change in the resonant part of the distribution function. Hence, in particular,
the incorrectness of the established in the literature point of view follows
that the fast, with velocities over V, and slow, with velocities under V,
trapped particles are described by the same distribution function. Also for the
first time it is shown that the self-generated strong electric field always
produces antitropic electron beams with the velocities much larger than the
value V, including the cold plasma limit. The possibility of implementing a new
class of self-consistent wave structures with a nonzero average potential is
shown. Maximum possible amplitude of a self-generated electric field in a
stationary collisionless plasma is determined.


title: A Calvin bestiary

abstract:
  This paper compares a number of mathematical models for the Calvin cycle of
photosynthesis and presents theorems on the existence and stability of steady
states of these models. Results on five-variable models in the literature are
surveyed. Next a number of larger models related to one introduced by
Pettersson and Ryde-Pettersson are discussed. The mathematical nature of this
model is clarified, showing that it is naturally defined as a system of
differential-algebraic equations. It is proved that there are choices of
parameters for which this model admits more than one positive steady state.
This is done by analysing the limit where the storage of sugars from the cycle
as starch is shut down. There is also a discussion of the minimal models for
the cycle due to Hahn.


title: A 17 GHz Molecular Rectifier

abstract:
  Molecular electronics originally proposed that small molecules sandwiched
between electrodes would accomplish electronic functions and enable to reach
ultimate scaling. However, so far, functional molecular devices have been only
demonstrated at low frequency. Here, we demonstrate molecular diodes operating
up to 17.8 GHz. DC (direct current) and RF (radio frequency) properties were
simultaneously measured on a large array of molecular junctions composed of
gold nanocrystal electrodes, ferrocenyl undecanethiol molecules, and the tip of
an interferometric scanning microwave microscope. The present nanometer-scale
molecular diodes offer a current density increase by several orders of
magnitude compared to that of micrometer-scale molecular diodes, allowing RF
operation. The measured S11 parameters show a diode rectification ratio of 12
dB which is linked to the rectification behavior of the DC conductance. From
the RF measurements, we extrapolate a cut-off frequency of 520 GHz. A
comparison with the silicon RFSchottky diodes architecture suggests that the
RF-molecular diodes are extremely attractive for scaling and high-frequency
operation.


title: The Hitchin fibration under degenerations to noded Riemann surfaces

abstract:
  In this note we study some analytic properties of the linearized self-duality
equations on a family of smooth Riemann surfaces $\Sigma_R$ converging for
$R\searrow0$ to a surface $\Sigma_0$ with a finite number of nodes. It is shown
that the linearization along the fibres of the Hitchin fibration gives rise to
a graph-continuous Fredholm family, the index of it being stable when passing
to the limit. We also report on similarities and differences between properties
of the Hitchin fibration in this degeneration and in the limit of large Higgs
fields.


title: On Weyl products and uniform distribution modulo one

abstract:
  In the present paper we study the asymptotic behavior of trigonometric
products of the form $\prod_{k=1}^N 2 \sin(\pi x_k)$ for $N \to \infty$, where
the numbers $\omega=(x_k)_{k=1}^N$ are evenly distributed in the unit interval
$[0,1]$. The main result are matching lower and upper bounds for such products
in terms of the star-discrepancy of the underlying points $\omega$, thereby
improving earlier results obtained by Hlawka in 1969. Furthermore, we consider
the special cases when the points $\omega$ are the initial segment of a
Kronecker or van der Corput sequence. The paper concludes with some
probabilistic analogues.


title: Gold Photoluminescence Wavelength and Polarization Engineering

abstract:
  We demonstrate engineering of the spectral content and polarization of
photoluminescence (PL) from arrayed gold nanoparticles atop a
subwavelength-thin dielectric spacer and optically-thick gold film, a
configuration that supports gap-surface plasmon resonances (GSPRs). Choice of
shapes and dimensions of gold nanoparticles influences the GSPR wavelength and
polarization characteristics, thereby allowing us to enhance and spectrally
mold the plasmon-assisted PL while simultaneously controlling its polarization.
In order to understand the underlying physics behind the plasmon-enhanced PL,
we develop a simple model that faithfully reproduces all features observed in
our experiments showing also good quantitative agreement for the PL enhancement


title:
Indicators as judgment devices: Citizen bibliometrics in biomedicine and
  economics

abstract:
  The number of publications has been a fundamental merit in the competition
for academic positions since the late 18th century. Today, the simple counting
of publications has been supplemented with a whole range of bibliometric
measures, which supposedly not only measures the volume of research but also
its impact. In this study, we investigate how bibliometrics are used for
evaluating the impact and quality of publications in two specific settings:
biomedicine and economics. Our study exposes the extent and type of metrics
used in external evaluations of candidates for academic positions at Swedish
universities. Moreover, we show how different bibliometric indicators, both
explicitly and implicitly, are employed to value and rank candidates. Our
findings contribute to a further understanding of bibliometric indicators as
judgment devices that are employed in evaluating individuals and their
published works within specific fields. We also show how expertise in using
bibliometrics for evaluative purposes is negotiated at the interface between
domain knowledge and skills in using indicators. In line with these results we
propose that the use of metrics in this context is best described as a form of
citizen bibliometrics - an underspecified term which we build upon in the
paper.


title: Hybridized exciton-polariton resonances in core-shell nanoparticles

abstract:
  The goal of nanophotonics is to control and manipulate light at length scales
below the diffraction limit. Typically nanostructured metals are used for this
purpose, light being confined by exploiting the surface plasmon-polaritons such
structures support. Recently excitonic (molecular) materials have been
identified as an alternative candidate material for nanophotonics. Here we use
theoretical modelling to explore how hybridisation of surface
exciton-polaritons can be achieved through appropriate nanostructuring. We
focus on the extent to which the frequency of the hybridised modes can be
shifted with respect to the underlying material resonances.


title:
Note on the quasi-proper direct image with value in a Banach analytic
  set

abstract:
  We give a rather simple proof of the generalization of Kuhlmann's
quasi-proper direct image theorem to the case of a map with values in a Banach
analytic set. The proof uses a generalization of the Remmert-Stein's theorem to
this context. AMS Classification. 32 H 02-32 K 05-32 C 25.


title: DBD in burst mode: solution for more efficient CO2 conversion?

abstract:
  CO2 conversion into value-added products has gained significant interest over
the few last years, as the greenhouse gas concentrations constantly increase
due to anthropogenic activities. Here we report on experiments for CO2
conversion by means of a cold atmospheric plasma using a cylindrical flowing
dielectric barrier discharge (DBD) reactor. A detailed comparison of this DBD
ignited in a so-called burst mode (i.e. where an AC voltage is applied during a
limited amount of time) and pure AC mode is carried out to evaluate their
effect on the conversion of CO2 as well as on the energy efficiency. Decreasing
the duty cycle in the burst mode from 100% (i.e. corresponding to pure AC mode)
to 40% leads to a rise in the conversion from 16--26% and to a rise in the
energy efficiency from 15 to 23%. Based on a detailed electrical analysis, we
show that the conversion correlates with the features of the microfilaments.
Moreover, the root-mean-square voltage in the burst mode remains constant as a
function of the process time for the duty cycles \textless{}70%, while a higher
duty cycle or the usual pure AC mode leads to a clear voltage decay by more
than 500 V, over approximately 90 s, before reaching a steady state regime. The
higher plasma voltage in the burst mode yields a higher electric field. This
causes the increasing the electron energy, and therefore their involvement in
the CO2 dissociation process, which is an additional explanation for the higher
CO2 conversion and energy efficiency in the burst mode.


title:
How do the barrier thickness and dielectric material influence the
  filamentary mode and CO2 conversion in a flowing DBD?

abstract:
  Dielectric barrier discharges (DBDs) are commonly used to generate cold
plasmas at atmospheric pressure. Whatever their configuration (tubular or
planar), the presence of a dielectric barrier is mandatory to prevent too much
charge build up in the plasma and the formation of a thermal arc. In this
article, the role of the barrier thickness (2.0, 2.4 and 2.8 mm) and of the
kind of dielectric material (alumina, mullite, pyrex, quartz) is investigated
on the filamentary behavior in the plasma and on the CO2 conversion in a
tubular flowing DBD, by means of mass spectrometry measurements correlated with
electrical characterization and IR imaging. Increasing the barrier thickness
decreases the capacitance, while preserving the electrical charge. As a result,
the voltage over the dielectric increases and a larger number of
microdischarges is generated, which enhances the CO2 conversion. Furthermore,
changing the dielectric material of the barrier, while keeping the same
geometry and dimensions, also affects the CO2 conversion. The highest CO2
conversion and energy efficiency are obtained for quartz and alumina, thus not
following the trend of the relative permittivity. From the electrical
characterization, we clearly demonstrate that the most important parameters are
the somewhat higher effective plasma voltage (yielding a somewhat higher
electric field and electron energy in the plasma) for quartz, as well as the
higher plasma current (and thus larger electron density) and the larger number
of microdischarge filaments (mainly for alumina, but also for quartz). The
latter could be correlated to the higher surface roughness for alumina and to
the higher voltage over the dielectric for quartz.


title:
Reactivity of water vapor in an atmospheric argon flowing post-discharge
  plasma torch

abstract:
  The reactivity of water vapor introduced in the flowing post-discharge of an
RF atmospheric plasma torch is investigated through electrical
characterization, optical emission spectroscopy and mass spectrometry
measurements. Due to the technical features of the plasma torch, the
post-discharge can be considered as divided into two regions: an inner region
(inside the plasma torch device) where the water vapor is injected and an outer
region which directly interacts with the ambient air. The main reactions
induced by the injection of water vapor are identified as well as those
indicative of the influence of the ambient air. Plausible pathways allowing the
production of H, OH, O radicals and H2O2 are discussed as well as reactions
potentially responsible for inhomogeneities and for a low DC current measured
in the flowing post-discharge. Keywords: atmospheric post-discharge, H2O plasma
reactivity, RF plasma torch


title:
Enhanced non-resonant light transmission through subwavelength slits in
  metal

abstract:
  We analytically describe light transmission through a single subwavelength
slit in a thin perfect electric conductor screen for the incident polarization
being perpendicular to the slit, and derive simple, yet accurate, expressions
for the average electric field in the slit and the transmission efficiency. The
analytic results are consistent with full-wave numerical calculations, and
demonstrate that slits of widths ~100nm in real metals may feature non-resonant
(i.e., broadband) field enhancements of ~100 and transmission efficiency of ~10
at infrared or terahertz frequencies, with the associated metasurface-like
array of slits becoming transparent to the incident light.


title: Image-to-Markup Generation with Coarse-to-Fine Attention

abstract:
  We present a neural encoder-decoder model to convert images into
presentational markup based on a scalable coarse-to-fine attention mechanism.
Our method is evaluated in the context of image-to-LaTeX generation, and we
introduce a new dataset of real-world rendered mathematical expressions paired
with LaTeX markup. We show that unlike neural OCR techniques using CTC-based
models, attention-based approaches can tackle this non-standard OCR task. Our
approach outperforms classical mathematical OCR systems by a large margin on
in-domain rendered data, and, with pretraining, also performs well on
out-of-domain handwritten data. To reduce the inference complexity associated
with the attention-based approaches, we introduce a new coarse-to-fine
attention layer that selects a support region before applying attention.


title: Splitting theorems for hypersurfaces in Lorentzian manifolds

abstract:
  This paper looks at the splitting problem for globally hyperbolic spacetimes
with timelike Ricci curvature bounded below containing a (spacelike, acausal,
future causally complete) hypersurface with mean curvature bounded from above.
For such spacetimes we show a splitting theorem under the assumption of either
the existence of a ray of maximal length or a maximality condition on the
volume of Lorentzian distance balls over the hypersurface. The proof of the
first case follows work by Andersson, Galloway and Howard and uses their
geometric maximum principle for level sets of the (Lorentzian) Busemann
function. For the second case we give a more elementary proof.


title:
Improving the Transmittance of an Epsilon-Near-Zero based Wavefront
  Shaper

abstract:
  Although Epsilon-Near-Zero metamaterials (ENZ) offer many unconventional ways
to play with light, the optical impedance mismatch with surroundings can limit
the efficiency of future devices. We report here on the improvement of the
transmittance of an Epsilon-Near-Zero (ENZ) wavefront shaper. We first address
in this paper the way to enhance the transmittance of a plane wave through a
layer of ENZ material thanks to a numerical optimization approach based on the
Transfer Matrix Method. We then transpose the one dimensional approach to a two
dimensional case where the emission of a dipole is shaped into a plane wave by
an ENZ device with a design that optimizes the transmittance. As a result, we
demonstrate a transmittance efficiency of 15 \% that is 4 orders of magnitude
higher than previous devices proposed in the literature for wavefront shaping
applications. This work aims at paving the way for future efficient ENZ devices
by offering new strategies to optimize the transmittance through ENZ materials.


title: A new observable in extensive air showers

abstract:
  We find that the ratio r_{mu e} of the muon to the electromagnetic component
of an extended air shower at the ground level provides an indirect measure of
the depth X_{max} of the shower maximum. This result, obtained with the
air-shower code AIRES, is independent of the hadronic model used in the
simulation. We show that the value of r_{mu e} in a particular shower
discriminates its proton or iron nature with a 98% efficiency. We also show
that the eventual production of forward heavy quarks inside the shower may
introduce anomalous values of r_{mu e} in isolated events.


title:
Linearly increasing radius of the light fragment during the spontaneous
  fission of $^{282}$Cn

abstract:
  In a previous article published in Phys. Rev. C 94 (2016) 014309 we have
shown for the first time that the best dynamical trajectory during the
deformation toward fission of the superheavy nucleus $^{286}$Fl is a linearly
increasing radius of the light fragment, $R_2$. This macroscopic-microscopic
result reminds us about the $\alpha $ or cluster preformation at the nuclear
surface, assumed already in 1928, and proved microscopically many times. This
time we give more detailed arguments for the neighboring nucleus $^{282}$Cn.
Also similar figures are presented for heavy nuclei $^{240}$Pu and $^{252}$Cf.
The deep minimum of total deformation energy near the surface is shown for the
first time as a strong argument for cluster preformation.


title: Convergence of Dynamics and the Perron-Frobenius Operator

abstract:
  We complete the picture how the asymptotic behavior of a dynamical system is
reflected by properties of the associated Perron-Frobenius operator. Our main
result states that strong convergence of the powers of the Perron-Frobenius
operator is equivalent to setwise convergence of the underlying dynamic in the
measure algebra. This situation is furthermore characterized by a uniform
mixing-like property of the system.


title:
Spatial firm competition in two dimensions with linear transportation
  costs: simulations and analytical results

abstract:
  Models of spatial firm competition assume that customers are distributed in
space and transportation costs are associated with their purchases of products
from a small number of firms that are also placed at definite locations. It has
been long known that the competition equilibrium is not guaranteed to exist if
the most straightforward linear transportation costs are assumed. We show by
simulations and also analytically that if periodic boundary conditions in two
dimensions are assumed, the equilibrium exists for a pair of firms at any
distance. When a larger number of firms is considered, we find that their total
equilibrium profit is inversely proportional to the square root of the number
of firms. We end with a numerical investigation of the system's behavior for a
general transportation cost exponent.


title:
High-pressure study of the basal-plane anisotropy of the upper critical
  field of the topological superconductor SrxBi2Se3

abstract:
  We report a high-pressure transport study of the upper-critical field,
$B_{c2}(T)$, of the topological superconductor Sr$_{0.15}$Bi$_2$Se$_3$ ($T_c =
3.0$ K). $B_{c2}(T)$ was measured for magnetic fields directed along two
orthogonal directions, $a$ and $a^*$, in the trigonal basal plane. While
superconductivity is rapidly suppressed at the critical pressure $p_c \sim 3.5$
GPa, the pronounced two-fold basal-plane anisotropy $B_{c2}^a/B_{c2}^{a^*} =
3.2$ at $T=0.3$ K, recently reported at ambient pressure (Pan et al., 2016), is
reinforced and attains a value of $\sim 5$ at the highest pressure (2.2 GPa).
The data reveal that the unconventional superconducting state with broken
rotational symmetry is robust under pressure.


title: Robot Contact Task State Estimation via Action Grammars

abstract:
  Uncertainty is a major difficulty in endowing robots with autonomy. Robots
often fail due to unexpected events. In robot contact tasks are often design to
empirically look for force thresholds to define state transitions in a Markov
chain or finite state machines. Such design is prone to failure in unstructured
environments, when due to external disturbances or erroneous models, such
thresholds are met, and lead to state transitions that are false-positives. The
focus of this paper is to perform high-level state estimation of robot
behaviors and task output for robot contact tasks. Our approach encodes raw
low-level 3D cartesian trajectories and converts them into a high level (HL)
action grammars. Cartesian trajectories can be segmented and encoded in a way
that their dynamic properties, or "texture" are preserved. Once an action
grammar is generated, a classifier is trained to detect current behaviors and
ultimately the task output. The system executed HL state estimation for task
output verification with an accuracy of 86%, and behavior monitoring with an
average accuracy of: 72%. The significance of the work is the transformation of
difficult-to-use raw low-level data to HL data that enables robust behavior and
task monitoring. Monitoring is useful for failure correction or other
deliberation in high-level planning, programming by demonstration, and
human-robot interaction to name a few.


title: Robot Introspection via Wrench-based Action Grammars

abstract:
  Robotic failure is all too common in unstructured robot tasks. Despite well
designed controllers, robots often fail due to unexpected events. How do robots
measure unexpected events? Many do not. Most robots are driven by the
senseplan- act paradigm, however more recently robots are working with a
sense-plan-act-verify paradigm. In this work we present a principled
methodology to bootstrap robot introspection for contact tasks. In effect, we
are trying to answer the question, what did the robot do? To this end, we
hypothesize that all noisy wrench data inherently contains patterns that can be
effectively represented by a vocabulary. The vocabulary is generated by
meaningfully segmenting the data and then encoding it. When the wrench
information represents a sequence of sub-tasks, we can think of the vocabulary
forming sets of words or sentences, such that each subtask is uniquely
represented by a word set. Such sets can be classified using statistical or
machine learning techniques. We use SVMs and Mondrian Forests to classify
contacts tasks both in simulation and in real robots for one and dual arm
scenarios showing the general robustness of the approach. The contribution of
our work is the presentation of a simple but generalizable semantic scheme that
enables a robot to understand its high level state. This verification mechanism
can provide feedback for high-level planners or reasoning systems that use
semantic descriptors as well. The code, data, and other supporting
documentation can be found at:
http://www.juanrojas.net/2017icra_wrench_introspection.


title: Orion revisited III. The Orion Belt population

abstract:
  This paper continues our study of the foreground population to the Orion
molecular clouds. The goal is to characterize the foreground population north
of NGC 1981 and to investigate the star formation history in the large Orion
star-forming region. We focus on a region covering about 25 square degrees,
centered on the $\epsilon$ Orionis supergiant (HD 37128, B0\,Ia) and covering
the Orion Belt asterism.
  We used a combination of optical (SDSS) and near-infrared (2MASS) data,
informed by X-ray (\textit{XMM-Newton}) and mid-infrared (WISE) data, to
construct a suite of color-color and color-magnitude diagrams for all available
sources. We then applied a new statistical multiband technique to isolate a
previously unknown stellar population in this region.
  We identify a rich and well-defined stellar population in the surveyed region
that has about 2\,000 objects that are mostly M stars. We infer the age for
this new population to be at least 5\, Myr and likely $\sim10$\,Myr and
estimate a total of about 2\,500 members, assuming a normal IMF. This new
population, which we call the Orion Belt population, is essentially
extinction-free, disk-free, and its spatial distribution is roughly centered
near $\epsilon$ Ori, although substructure is clearly present.
  The Orion Belt population is likely the low-mass counterpart to the Ori OB Ib
subgroup. Although our results do not rule out Blaauw's sequential star
formation scenario for Orion, we argue that the recently proposed blue streams
scenario provides a better framework on which one can explain the Orion star
formation region as a whole. We speculate that the Orion Belt population could
represent the evolved counterpart of an Orion nebula-like cluster.


title:
Zero level perturbation of a certain third-order linear solvable ODE
  with an irregular singularity at the origin of Poincar\'e rank 1

abstract:
  We study an irregular singularity of Poincar\'e rank 1 at the origin of a
certain third-order linear solvable homogeneous ODE. We perturb the equation by
introducing a small parameter $\varepsilon\in (\mathbb{R}_+, 0)\,(\varepsilon <
1)$ which causes the splitting of the irregular singularity into two finite
Fuchsian singularities. We show that when the solutions of the perturbed
equation contain logarithmic terms, the Stokes matrices of the initial equation
are limits of the part of the monodromy matrices around the finite resonant
Fuchsian singularities of the perturbed equation.


title:
Nonequilibrium mesoscopic conductance fluctuations as the origin of 1/f
  noise in epitaxial graphene

abstract:
  We investigate the 1/f noise properties of epitaxial graphene devices at low
temperatures as a function of temperature, current and magnetic flux density.
At low currents, an exponential decay of the 1/f noise power spectral density
with increasing temperature is observed that indicates mesoscopic conductance
fluctuations as the origin of 1/f noise at temperatures below 50 K. At higher
currents, deviations from the typical quadratic current dependence and the
exponential temperature dependence occur as a result of nonequilibrium
conditions due to current heating. By applying the theory of Kubakaddi [S. S.
Kubakaddi, Phys. Rev. B 79, 075417 (2009)], a model describing the 1/f noise
power spectral density of nonequilibrium mesoscopic conductance fluctuations in
epitaxial graphene is developed and used to determine the energy loss rate per
carrier. In the regime of Shubnikov-de Haas oscillations a strong increase of
1/f noise is observed, which we attribute to an additional conductance
fluctuation mechanism due to localized states in quantizing magnetic fields.
When the device enters the regime of quantized Hall resistance, the 1/f noise
vanishes. It reappears if the current is increased and the quantum Hall
breakdown sets in.


title: Finding Disjoint Paths on Edge-Colored Graphs: More Tractability Results

abstract:
  The problem of finding the maximum number of vertex-disjoint uni-color paths
in an edge-colored graph (called MaxCDP) has been recently introduced in
literature, motivated by applications in social network analysis. In this paper
we investigate how the complexity of the problem depends on graph parameters
(namely the number of vertices to remove to make the graph a collection of
disjoint paths and the size of the vertex cover of the graph), which makes
sense since graphs in social networks are not random and have structure. The
problem was known to be hard to approximate in polynomial time and not
fixed-parameter tractable (FPT) for the natural parameter. Here, we show that
it is still hard to approximate, even in FPT-time. Finally, we introduce a new
variant of the problem, called MaxCDDP, whose goal is to find the maximum
number of vertex-disjoint and color-disjoint uni-color paths. We extend some of
the results of MaxCDP to this new variant, and we prove that unlike MaxCDP,
MaxCDDP is already hard on graphs at distance two from disjoint paths.


title:
Passivity Analysis of Higher Order Evolutionary Dynamics and Population
  Games

abstract:
  In population games, a large population of players, modeled as a continuum,
is divided into subpopulations, and the fitness or payoff of each subpopulation
depends on the overall population composition. Evolutionary dynamics describe
how the population composition changes in response to the fitness levels,
resulting in a closed-loop feedback system. Recent work established a
connection between passivity theory and certain classes of population games,
namely so-called "stable games". In particular, it was shown that a combination
of stable games and (an analogue of) passive evolutionary dynamics results in
stable convergence to Nash equilibrium. This paper considers the converse
question of necessary conditions for evolutionary dynamics to exhibit stable
behaviors for all generalized stable games. Here, generalization refers to
"higher order" games where the population payoffs may be a dynamic function of
the population state. Using methods from robust control analysis, we show that
if an evolutionary dynamic does not satisfy a passivity property, then it is
possible to construct a generalized stable game that results in instability.
The results are illustrated on selected evolutionary dynamics with particular
attention to replicator dynamics, which are also shown to be lossless, a
special class of passive systems.


title: Inflationary Universe with a Viscous Fluid Avoiding Self-Reproduction

abstract:
  We consider a universe with a bulk viscous cosmic fluid, in a flat
Friedmann-Lemaitre-Robertson-Walker geometry. We derive the conditions for the
existence of inflation, and those which at the same time prevent the occurrence
of self-reproduction. Our theoretical model gives results which are in perfect
agreement with the most recent data from the PLANCK surveyor.


title: Inference of magnetic fields in inhomogeneous prominences

abstract:
  Most of the quantitative information about the magnetic field vector in solar
prominences comes from the analysis of the Hanle effect acting on lines formed
by scattering. As these lines can be of non-negligible optical thickness, it is
of interest to study the line formation process further. We investigate the
multidimensional effects on the interpretation of spectropolarimetric
observations, particularly on the inference of the magnetic field vector. We do
this by analyzing the differences between multidimensional models, which
involve fully self-consistent radiative transfer computations in the presence
of spatial inhomogeneities and velocity fields, and those which rely on simple
one-dimensional geometry. We study the formation of a prototype line in ad hoc
inhomogeneous, isothermal 2D prominence models. We solve the NLTE polarized
line formation problem in the presence of a large-scale oriented magnetic
field. The resulting polarized line profiles are then interpreted (i.e.
inverted) assuming a simple 1D slab model. We find that differences between
input and the inferred magnetic field vector are non-negligible. Namely, we
almost universally find that the inferred field is weaker and more horizontal
than the input field. Spatial inhomogeneities and radiative transfer have a
strong effect on scattering line polarization in the optically thick lines. In
real-life situations, ignoring these effects could lead to a serious
misinterpretation of spectropolarimetric observations of chromospheric objects
such as prominences.


title: Authcoin: Validation and Authentication in Decentralized Networks

abstract:
  Authcoin is an alternative approach to the commonly used public key
infrastructures such as central authorities and the PGP web of trust. It
combines a challenge response-based validation and authentication process for
domains, certificates, email accounts and public keys with the advantages of a
block chain-based storage system. As a result, Authcoin does not suffer from
the downsides of existing solutions and is much more resilient to sybil
attacks.


title:
Export dynamics as an optimal growth problem in the network of global
  economy

abstract:
  We analyze export data aggregated at world global level of 219 classes of
products over a period of 39 years. Our main goal is to set up a dynamical
model to identify and quantify plausible mechanisms by which the evolutions of
the various exports affect each other. This is pursued through a stochastic
differential description, partly inspired by approaches used in population
dynamics or directed polymers in random media. We outline a complex network of
transfer rates which describes how resources are shifted between different
product classes, and determines how casual favorable conditions for one export
can spread to the other ones. A calibration procedure allows to fit four free
model-parameters such that the dynamical evolution becomes consistent with the
average growth, the fluctuations, and the ranking of the export values observed
in real data. Growth crucially depends on the balance between maintaining and
shifting resources to different exports, like in an explore-exploit problem.
Remarkably, the calibrated parameters warrant a close-to-maximum growth rate
under the transient conditions realized in the period covered by data, implying
an optimal self organization of the global export. According to the model,
major structural changes in the global economy take tens of years.


title:
Experimental evidence of $T_c$ enhancement without the influence of spin
  fluctuations: NMR study on LaFeAsO_{1-x}H_x under a pressure of 3.0 GPa

abstract:
  The electron-doped high-transition-temperature (T_c) iron-based pnictide
superconductor LaFeAsO_{1-x}H_x has a unique phase diagram: superconducting
(SC) double domes are sandwiched by antiferromagnetic phases at ambient
pressure and they turn to a single dome with a maximum T_c that exceeds 45K at
a pressure of 3.0 GPa. We studied whether spin fluctuations are involved in
increasing T_c under a pressure of 3.0 GPa by using ^{75}As nuclear magnetic
resonance (NMR) technique. The ^{75}As-NMR results for the powder samples show
that T_c increases up to 48 K without the influence of spin fluctuations. The
fact indicates that spin fluctuations are not involved in raising T_c, which
implies that other factors, such as orbital degrees of freedom, may be
important for achieving a high T_c of almost 50 K.


title:
Gender differences in appropriate shocks and mortality among patients
  with primary prophylactic implantable cardioverter-defibrillators: Systematic
  review and meta-analysis

abstract:
  BACKGROUND: Some but not all prior studies have shown that women receiving a
primary prophylactic implantable cardioverter defibrillator (ICD) have a lower
risk of death and appropriate shocks than men.
  PURPOSE: To evaluate the effect of gender on the risk of appropriate shock,
all-cause mortality and inappropriate shock in contemporary studies of patients
receiving a primary prophylactic ICD.
  DATA SOURCE: PubMed, LIVIVO, Cochrane CENTRAL between 2010 and 2016.
  STUDY SELECTION: Studies providing at least 1 gender-specific risk estimate
for the outcomes of interest.
  DATA EXTRACTION: Abstracts were screened independently for potentially
eligible studies for inclusion. Thereby each abstract was reviewed by at least
two authors.
  DATA SYNTHESIS: Out of 680 abstracts retained by our search strategy, 20
studies including 46'657 patients had gender-specific information on at least
one of the relevant endpoints. Mean age across the individual studies varied
between 58 and 69 years. The proportion of women enrolled ranged from 10% to
30%. Across 6 available studies, women had a significantly lower risk of first
appropriate shock compared with men (pooled multivariable adjusted hazard ratio
0.62 (95% CI [0.44; 0.88]). Across 14 studies reporting multivariable adjusted
gender-specific hazard ratio estimates for all-cause mortality, women had a
lower risk of death than men (pooled hazard ratio 0.75 (95% CI [0.66; 0.86]).
There was no statistically significant difference for the incidence of first
inappropriate shocks (3 studies, pooled hazard ratio 0.99 (95% CI [0.56;
1.73]).
  CONCLUSION: In this large contemporary meta-analysis, women had a
significantly lower risk of appropriate shocks and death than men, but a
similar risk of inappropriate shocks. These data may help to select patients
who benefit from primary prophylactic ICD implantation.


title:
Inflation with teleparallelism: Can torsion generate primordial
  fluctuations without local Lorentz symmetry?

abstract:
  Arbitrary generalization to the teleparallel equivalent of general relativity
loses local Lorentz invariance to reparametrize the orthonormal coordinate
system and gives rise to asymmetry field equations. We investigate consequences
of local Lorentz violation to primordial fluctuations in extended single field
inflationary models based on the scalar-tensor formulation of the torsion
scalar $T$ that effectively includes $f(T)$ gravity as a special case. We show
that despite some asymmetry part of the field equations are removed in a
spatially homogeneous and isotropic cosmic background, no subhorizon
scalar-perturbation mode can survive by the time of horizon crossing. As a
result, any scalar field mediated in torsion cannot generate enough primordial
density inhomogeneity alone, even if it brings some de Sitter background
solutions in generalized teleparallel gravity.


title: On Covering Codes and Upper Bounds for the Dimension of Simple Games

abstract:
  Consider a situation with $n$ agents or players where some of the players
form a coalition with a certain collective objective. Simple games are used to
model systems that can decide whether coalitions are successful (winning) or
not (losing). A simple game can be viewed as a monotone boolean function. The
dimension of a simple game is the smallest positive integer $d$ such that the
simple game can be expressed as the intersection of $d$ threshold functions
where each threshold function uses a threshold and $n$ weights. Taylor and
Zwicker have shown that $d$ is bounded from above by the number of maximal
losing coalitions. We present two new upper bounds both containing the
Taylor/Zwicker-bound as a special case. The Taylor/Zwicker-bound imply an upper
bound of ${n \choose n/2}$. We improve this upper bound significantly by
showing constructively that $d$ is bounded from above by the cardinality of any
binary covering code with length $n$ and covering radius $1$. This result
supplements a recent result where Olsen et al. showed how to construct simple
games with dimension $|C|$ for any binary constant weight SECDED code $C$ with
length $n$. Our result represents a major step in the attempt to close the
dimensionality gap for simple games.


title: Limit theory for the empirical extremogram of random fields

abstract:
  Regularly varying stochastic processes are able to model extremal dependence
between process values at locations in random fields. We investigate the
empirical extremogram as an estimator of dependence in the extremes. We provide
conditions to ensure asymptotic normality of the empirical extremogram centred
by a pre-asymptotic version. For max-stable processes with Fr{\'e}chet margins
we provide conditions such that the empirical extremogram centred by its true
version is asymptotically normal. The results of this paper apply to a variety
of spatial and space-time processes, and to time series models. We apply our
results to max-moving average processes and Brown-Resnick processes.


title: Quasi-thin weakly distance-regular digraphs

abstract:
  A weakly distance-regular digraph is quasi-thin if the maximum value of its
intersection numbers is 2. In this paper, we focus on commutative quasi-thin
weakly distance-regular digraphs, and classify such digraphs with valency more
than 3. As a result, this family of digraphs are completely determined.


title:
Proper motion survey and kinematic analysis of the Rho Ophiuchi embedded
  cluster

abstract:
  We aim at performing a kinematic census of young stellar objects (YSOs) in
the Rho Ophiuchi F core and partially in the E core of the L1688 dark cloud. We
run a proper motion program at the ESO New Technology Telescope (NTT) with the
Son of ISAAC (SOFI) instrument over nine years in the near-infrared. We
complemented these observations with various public image databases to enlarge
the time base of observations and the field of investigation to 0.5 deg X 0.5
deg. We derived positions and proper motions for 2213 objects. From these, 607
proper motions were derived from SOFI observations with a ~1.8 mas/yr accuracy
while the remaining objects were measured only from auxiliary data with a mean
precision of about ~3 mas/yr. We performed a kinematic analysis of the most
accurate proper motions derived in this work, which allowed us to separate
cluster members from field stars and to derive the mean properties of the
cluster. From the kinematic analysis we derived a list of 68 members and 14
candidate members, comprising 26 new objects with a high membership
probability. These new members are generally fainter than the known ones. We
measured a mean proper motion of (mu_RA*, mu_DEC)=(-8.2, -24.3)+/-0.8 mas/yr
for the L1688 dark cloud. A supervised classification was applied to
photometric data of members to allocate a spectral energy distribution (SED)
classification to the unclassified members.} We kinematically confirmed that
the 56 members that were known from previous studies of the Rho Ophiuchi F
cluster and that were also part of our survey are members of the cluster, and
we added 26 new members. We defined the evolutionary status of the unclassified
members of the cluster. We showed that a large part (23) of these new members
are probably brown dwarfs, which multiplies the number of known substellar
objects in the cluster by a factor of 3.3.


title: Un r\'esultat de recherche obtenu gr\^ace \`a des lyc\'eens

abstract:
  We give an elementary proof of a question asked by Fouvry, Kowalski and
Michel on the solutions of the equation $x+\frac{1}{x}+y+\frac{1}{y}+t=0$ over
a finite field, using the results obtained by highschool students during their
participation at the maths tournament "Tournoi Fran\c{c}ais des Jeunes
Math\'ematiciennes et Math\'ematiciens".
  Nous pr\'esentons une d\'emonstration \'el\'ementaire d'une question pos\'ee
par Fouvry, Kowalski et Michel sur les solutions de l'\'equation
$x+\frac{1}{x}+y+\frac{1}{y}+t=0$ sur un corps fini, en utilisant des
r\'esultats obtenus par des lyc\'eens lors de leur participation au Tournoi
Fran\c{c}ais des Jeunes Math\'ematiciennes et Math\'ematiciens.


title: Coherence protection in coupled quantum systems

abstract:
  The interaction of a quantum system with its environment causes decoherence,
setting a fundamental limit on the suitability of a system for quantum
information processing. However, we show that if the quantum system consists of
coupled parts with different internal energy scales then the interaction of one
part with a thermal bath need not lead to loss of coherence from the other.
Remarkably, we find that the protected part can become more coherent when the
coupling to the bath becomes stronger or the temperature is raised. Our theory
will enable the design of decoherence-resistant hybrid quantum computers.


title: Photon polarization tensor in a magnetized plasma system

abstract:
  We investigate the photon polarization tensor at finite temperature in the
presence of a static and homogeneous external magnetic field. In our scheme,
the Matsubara frequency summation is performed after Poisson summation, which
will be taken easily and convergent quickly in the frame of proper time
representation. Moreover, the dependence of Landau levels is expressed
explicitly. It demonstrates the convergence of summing Landau levels as it has
to be. Consequently, there is no necessary to truncate the Landau level in a
numerical estimation. At zero temperature, the Lowest Landau Level (LLL)
approximation is analytically satisfied for the imaginary parts of the vacuum
photon polarization tensor. Our results examine that, the LLL approximation is
not enough for the thermal photon polarization tensor, it gains the
contribution not only from the lowest Landau level but also up to the
finite-$n$ levels. Such large imaginary ones only show up at finite
temperatures, which is the so called Landau damping. It originates from the
absorption of soft fields by hard plasma constituents, which is a universal
feature of plasma systems. Finally, it was argued that the summation of
Matsubara frequency is not commuted with Landau level ones, such conjecture is
excluded in our calculations.


title: Semiparametric estimation for isotropic max-stable space-time processes

abstract:
  Regularly varying space-time processes have proved useful to study extremal
dependence in space-time data. We propose a semiparametric estimation procedure
based on a closed form expression of the extremogram to estimate parametric
models of extremal dependence functions. We establish the asymptotic properties
of the resulting parameter estimates and propose subsampling procedures to
obtain asymptotically correct confidence intervals. A simulation study shows
that the proposed procedure works well for moderate sample sizes and is robust
to small departures from the underlying model. Finally, we apply this
estimation procedure to fitting a max-stable process to radar rainfall
measurements in a region in Florida. Complementary results and some proofs of
key results are presented together with the simulation study in the supplement.