title:
Improved Rademacher symmetrization through a Wasserstein based measure
  of asymmetry

abstract:
  We propose of an improved version of the ubiquitous symmetrization inequality
making use of the Wasserstein distance between a measure and its reflection in
order to quantify the symmetry of the given measure. An empirical bound on this
asymmetric correction term is derived through a bootstrap procedure and shown
to give tighter results in practical settings than the original uncorrected
inequality. Lastly, a wide range of applications are detailed including testing
for data symmetry, constructing nonasymptotic high dimensional confidence sets,
bounding the variance of an empirical process, and improving constants in
Nemirovski style inequalities for Banach space valued random variables.


title:
Hydrogen bonding in the protic ionic liquid triethylammonium nitrate
  explored by density functional tight binding simulations

abstract:
  The applicability of the density functional based tight binding (DFTB) method
to the description of hydrogen bond dynamics and infrared spectroscopy is
addressed for the exemplary protic ionic liquid triethylammonium nitrate.
Potential energy curves for proton transfer in gas and liquid phase are shown
to be comparable to high level coupled cluster theory in the thermally
accessible range of bond lengths. Geometric correlations in the hydrogen bond
dynamics are analyzed for a cluster of six ion pairs. Comparing DFTB and
regular DFT data lends further support for the reliability of the DFTB method.
Therefore, DFTB bulk simulations are performed to quantify the extent of
geometric correlations in terms of Pauling's bond order model. Further,
infrared (IR) absorption spectra are obtained and analyzed putting emphasis on
the signatures of hydrogen bonding in the NH-stretching and far IR hydrogen
bond range.


title:
On the Exact Amount of Missing Information that makes Finding Possible
  Winners Hard

abstract:
  We consider election scenarios with incomplete information, a situation that
arises often in practice. There are several models of incomplete information
and accordingly, different notions of outcomes of such elections. In one
well-studied model of incompleteness, the votes are given by partial orders
over the candidates. In this context we can frame the problem of finding a
possible winner, which involves determining whether a given candidate wins in
at least one completion of a given set of partial votes for a specific voting
rule.
  The possible winner problem is well-known to be NP-complete in general, and
it is in fact known to be NP-complete for several voting rules where the number
of undetermined pairs in every vote is bounded only by some constant. In this
paper, we address the question of determining precisely the smallest number of
undetermined pairs for which the possible winner problem remains NP-complete.
In particular, we find the exact values of $t$ for which the possible winner
problem transitions to being NP-complete from being in P, where $t$ is the
maximum number of undetermined pairs in every vote. We demonstrate tight
results for a broad subclass of scoring rules which includes all the commonly
used scoring rules (such as plurality, veto, Borda, $k$-approval, and so on),
Copeland$^\alpha$ for every $\alpha\in[0,1]$, maximin, and Bucklin voting
rules. A somewhat surprising aspect of our results is that for many of these
rules, the possible winner problem turns out to be hard even if every vote has
at most one undetermined pair of candidates.


title:
Sum-networks: Dependency on Characteristic of the Finite Field under
  Linear Network Coding

abstract:
  Sum-networks are networks where all the terminals demand the sum of the
symbols generated at the sources. It has been shown that for any finite
set/co-finite set of prime numbers, there exists a sum-network which has a
vector linear solution if and only if the characteristic of the finite field
belongs to the given set. It has also been shown that for any positive rational
number $k/n$, there exists a sum-network which has capacity equal to $k/n$. It
is a natural question whether, for any positive rational number $k/n$, and for
any finite set/co-finite set of primes $\{p_1,p_2,\ldots,p_l\}$, there exists a
sum-network which has a capacity achieving rate $k/n$ fractional linear network
coding solution if and only if the characteristic of the finite field belongs
to the given set. We show that indeed there exists such a sum-network by
constructing such a sum-network.


title:
Resonance contribution of scalar color octet to $t \bar{t}$ production
  at the LHC in the minimal four color quark-lepton symmetry model

abstract:
  The scalar color octet contribution to the resonance $t\bar{t}$-pair
production at the LHC is calculated and analysed with account of the one loop
effective two gluon vertex. It is shown that this contribution from the scalar
color octet $F_2$ predicted by the minimal model with the four color
quark-lepton symmetry is for $\sqrt{s}=13$ TeV of about a few percents for $750
< m_{F_2} < 1800$ GeV and can exceed 10% for $400 < m_{F_2} < 750$ GeV. It is
also pointed out that the search for the scalar octet $F_2$ as the resonance in
the dijet mass spectra seems to be difficult because of the smallness of its
one loop effective two gluon interaction.


title:
Two problems concerning irreducible elements in rings of integers of
  number fields

abstract:
  Let $K$ be a number field with ring of integers $\mathbb{Z}_K$. We prove two
asymptotic formulas connected with the distribution of irreducible elements in
$\mathbb{Z}_K$. First, we estimate the maximum number of nonassociated
irreducibles dividing a nonzero element of $\mathbb{Z}_K$ of norm not exceeding
$x$ (in absolute value), as $x\to\infty$. Second, we count the number of
irreducible elements of $\mathbb{Z}_K$ of norm not exceeding $x$ lying in a
given arithmetic progression (again, as $x\to\infty$). When $K=\mathbb{Q}$,
both results are classical; a new feature in the general case is the influence
of combinatorial properties of the class group of $K$.


title: FROG: A Fast and Reliable Crowdsourcing Framework (Technical Report)

abstract:
  For decades, the crowdsourcing has gained much attention from both academia
and industry, which outsources a number of tasks to human workers. Existing
works considered improving the task accuracy through voting or learning
methods, they usually did not fully take into account reducing the latency of
the task completion. When a task requester posts a group of tasks (e.g.,
sentiment analysis), and one can only obtain answers of all tasks after the
last task is accomplished. As a consequence, the time delay of even one task in
this group could delay the next step of the task requester's work from minutes
to days, which is quite undesirable for the task requester.
  Inspired by the importance of the task accuracy and latency, in this paper,
we will propose a novel crowdsourcing framework, namely Fast and Reliable
crOwdsourcinG framework (FROG), which intelligently assigns tasks to workers,
such that the latencies of tasks are reduced and the expected accuracies of
tasks are met. Specifically, our FROG framework consists of two important
components, task scheduler and notification modules. For the task scheduler
module, we formalize a FROG task scheduling (FROG-TS) problem, in which the
server actively assigns workers with tasks with high reliability and low
latency. We prove that the FROG-TS problem is NP-hard. Thus, we design two
heuristic approaches, request-based and batch-based scheduling. For the
notification module, we define an efficient worker notifying (EWN) problem,
which only sends task invitations to those workers with high probabilities of
accepting the tasks. To tackle the EWN problem, we propose a smooth kernel
density estimation approach to estimate the probability that a worker accepts
the task invitation. Through extensive experiments, we demonstrate the
effectiveness and efficiency of our proposed FROG platform on both real and
synthetic data sets.


title:
Influence of the iron spin crossover in ferropericlase on the lower
  mantle geotherm

abstract:
  The iron spin crossover in ferropericlase introduces anomalies in its
thermodynamics and thermoelastic properties. Here we investigate how these
anomalies can affect the lower mantle geotherm. The effect is examined in
mantle aggregates consisting of mixtures of bridgmanite, ferropericlase, and
CaSiO$_3$ perovskite, with different Mg/Si ratios varying from harzburgitic to
perovskitic (Mg/Si$\sim$1.5 to 0.8). We find that the anomalies introduced by
the spin crossover increase the isentropic gradient and thus the geotherm
proportionally to the amount of ferropericlase. The geotherms can be as much as
$\sim$ 200K hotter than the conventional adiabatic geotherm at deep lower
mantle conditions. Aggregate elastic moduli and seismic velocities are also
sensitive to the spin crossover and the geotherm, which impacts analyses of
lower mantle velocities and composition.


title:
Adiabatic Interactions of Manakov Solitons -- Effects of
  Cross-modulation

abstract:
  We investigate the asymptotic behavior of the Manakov soliton trains
perturbed by cross-modulation in the adiabatic approximation. The multisoliton
interactions in the adiabatic approximation are modeled by a generalized
Complex Toda chain (GCTC). The cross-modulation requires special treating for
the evolution of the polarization vectors of the solitons. The numerical
predictions of the Manakov system are compared with the perturbed GCTC. For
certain set of initial parameters GCTC describes very well the long-time
evolution of the Manakov soliton trains.


title:
The Fellowship of LIBOR: A Study of Spurious Interbank Correlations by
  the Method of Wigner-Ville Function

abstract:
  The manipulation of LIBOR by a group of banks became one of the major blows
to the remaining confidence in financial industry. Yet, despite an enormous
amount of popular literature on the subject, rigorous time-series studies are
few. In my paper, I discuss the following hypothesis. Namely, if we should
assume for a statistical null, the quotes, which were submitted by the member
banks were true, the deviations from the LIBOR should have been entirely random
because they were determined by idiosyncratic conditions by the member banks.
This hypothesis can be statistically verified. Serial correlations of the
rates, which cannot be explained by the differences in credit qualities of the
member banks or the domicile Governments, were subjected to correlation tests.
A new econometric method--the analysis of the Wigner-Ville function borrowed
from quantum mechanics and signal processing--is used and explained for the
statistical interpretation of regression residuals.


title:
A Comparison of Various Electricity Tariff Price Forecasting Techniques
  in Turkey and Identifying the Impact of Time Series Periods

abstract:
  It is very vital for suppliers and distributors to predict the deregulated
electricity prices for creating their bidding strategies in the competitive
market area. Pre requirement of succeeding in this field, accurate and suitable
electricity tariff price forecasting tools are needed. In the presence of
effective forecasting tools, taking the decisions of production, merchandising,
maintenance and investment with the aim of maximizing the profits and benefits
can be successively and effectively done. According to the electricity demand,
there are four various electricity tariffs pricing in Turkey; monochromic, day,
peak and night. The objective is find the best suitable tool for predicting the
four pricing periods of electricity and produce short term forecasts (one year
ahead-monthly). Our approach based on finding the best model, which ensures the
smallest forecasting error measurements of: MAPE, MAD and MSD. We conduct a
comparison of various forecasting approaches in total accounts for nine teen,
at least all of those have different aspects of methodology. Our beginning step
was doing forecasts for the year 2015. We validated and analyzed the
performance of our best model and made comparisons to see how well the
historical values of 2015 and forecasted data for that specific period matched.
Results show that given the time-series data, the recommended models provided
good forecasts. Second part of practice, we also include the year 2015, and
compute all the models with the time series of January 2011 to December 2015.
Again by choosing the best appropriate forecasting model, we conducted the
forecast process and also analyze the impact of enhancing of time series
periods (January 2007 to December 2015) to model that we used for forecasting
process.


title:
Minimum spanning tree filtering of correlations for varying time scales
  and size of fluctuations

abstract:
  Based on a recently proposed $q$-dependent detrended cross-correlation
coefficient $\rho_q$, we generalize the concept of minimum spanning tree (MST)
by introducing a family of $q$-dependent minimum spanning trees ($q$MST) that
are selective to cross-correlations between different fluctuation amplitudes
and different time scales. They inherit this ability directly from the
coefficients $\rho_q$ that are processed here to construct a distance matrix.
Conventional MST with detrending corresponds in this context to $q=2$. We apply
the $q$MSTs to sample empirical data from the stock market and discuss the
results. We show that the $q$MST graphs can complement $\rho_q$ in
disentangling correlations that cannot be observed by the MST graphs based on
$\rho_{\rm DCCA}$ and, therefore, they can be useful in many areas where the
multivariate cross-correlations are of interest. We apply our method to data
from the stock market and obtain more information about correlation structure
of the data than by using $q=2$ only. We show that two sets of signals that
differ from each other statistically can give comparable trees for $q=2$, while
only by using the trees for $q \ne 2$ we become able to distinguish between
these sets. We also show that a family of $q$MSTs for a range of $q$ express
the diversity of correlations in a manner resembling the multifractal analysis,
where one computes a spectrum of the generalized fractal dimensions, the
generalized Hurst exponents, or the multifractal singularity spectra: the more
diverse the correlations are, the more variable the tree topology is for
different $q$s. Our analysis exhibits that the stocks belonging to the same or
similar industrial sectors are correlated via the fluctuations of moderate
amplitudes, while the largest fluctuations often happen to synchronize in those
stocks that do not necessarily belong to the same industry.


title: Probabilistic Linear Multistep Methods

abstract:
  We present a derivation and theoretical investigation of the Adams-Bashforth
and Adams-Moulton family of linear multistep methods for solving ordinary
differential equations, starting from a Gaussian process (GP) framework. In the
limit, this formulation coincides with the classical deterministic methods,
which have been used as higher-order initial value problem solvers for over a
century. Furthermore, the natural probabilistic framework provided by the GP
formulation allows us to derive probabilistic versions of these methods, in the
spirit of a number of other probabilistic ODE solvers presented in the recent
literature. In contrast to higher-order Runge-Kutta methods, which require
multiple intermediate function evaluations per step, Adams family methods make
use of previous function evaluations, so that increased accuracy arising from a
higher-order multistep approach comes at very little additional computational
cost. We show that through a careful choice of covariance function for the GP,
the posterior mean and standard deviation over the numerical solution can be
made to exactly coincide with the value given by the deterministic method and
its local truncation error respectively. We provide a rigorous proof of the
convergence of these new methods, as well as an empirical investigation (up to
fifth order) demonstrating their convergence rates in practice.


title:
Coherence Times of Bose-Einstein Condensates beyond the Shot-Noise Limit
  via Superfluid Shielding

abstract:
  We demonstrate a new way to extend the coherence time of separated
Bose-Einstein condensates that involves immersion into a superfluid bath. When
both the system and the bath have similar scattering lengths, immersion in a
superfluid bath cancels out inhomogeneous potentials either imposed by external
fields or inherent in density fluctuations due to atomic shot noise. This
effect, which we call superfluid shielding, allows for coherence lifetimes
beyond the projection noise limit. We probe the coherence between separated
condensates in different sites of an optical lattice by monitoring the contrast
and decay of Bloch oscillations. Our technique demonstrates a new way that
interactions can improve the performance of quantum devices.


title: Tracing where IoT data are collected and aggregated

abstract:
  The Internet of Things (IoT) offers the infrastructure of the information
society. It hosts smart objects that automatically collect and exchange data of
various kinds, directly gathered from sensors or generated by aggregations.
Suitable coordination primitives and analysis mechanisms are in order to design
and reason about IoT systems, and to intercept the implied technological
shifts. We address these issues from a foundational point of view. To study
them, we define IoT-LySa, a process calculus endowed with a static analysis
that tracks the provenance and the manipulation of IoT data, and how they flow
in the system. The results of the analysis can be used by a designer to check
the behaviour of smart objects, in particular to verify non-functional
properties, among which security.


title: Vector-Boson Fusion and Vector-Boson Scattering

abstract:
  Vector-boson fusion and vector-boson scattering are an important class of
processes for the Large Hadron Collider at CERN. It is characterized by two
high-energetic jets in the forward regions of the detector and reduced jet
activity in the central region. The higher center-of-mass energy during the
current and subsequent runs strongly boosts the sensitivity in these processes
and allows to test the predictions of the Standard Model to a high precision.
  In this review, we first present the main phenomenological features of
vector-boson fusion and scattering processes. Then we discuss the effects of
higher-order corrections, which are available at NLO QCD for all processes and
up to N3LO QCD and NLO electro-weak for VBF-H production. An additional
refinement is the addition of parton-shower effects, where recently a lot of
progress has been made. The appearance of triple and quartic gauge vertices in
the production processes enables us to probe anomalous gauge couplings. We
introduce and compare the different parametrizations used in the literature and
also discuss the issue of unitarity violation and common unitarization
procedures. Finally, we give a short overview of current and possible future
experimental searches.


title:
Indistinguishable quantum walks on graphs relative to a bipartite
  quantum walker

abstract:
  A distinguishability operator is defined for the continuous-time quantum walk
(CTQW) of a bipartite quantum walker on two simply connected graphs,
$W_{G_i,G_j} = U_{G_i}\left(t\right) \otimes U_{G_j}\left(t'\right) -
U_{G_j}\left(t'\right) \otimes U_{G_i}\left(t\right)$, where
$U_{G_i}\left(t\right)$ is the unitary CTQW operator for a labeled graph $G_i$
over a time interval $t$. The null space of $W_{G_i,G_j}$ defines the vector
space of initial bipartite states whose time development is either constant or
only dependent on $t + t'$ and is invariant to which quantum walker subsystem
goes with each graph. The set of null spaces corresponding with a set of
$W_{G_i,G_j}$ have interesting relations as subspaces, intersections between
subspaces, and subspaces of intersections. These relations are depicted as
Euler diagrams for labeled graphs of three and four vertices.


title: A large deviation principle for weighted Riesz interactions

abstract:
  We prove a large deviation principle for the sequence of push-forwards of
empirical measures in the setting of Riesz potential interactions on compact
subsets K in R^d with continuous external fields. Our results are valid for
base measures on K satisfying a strong Bernstein-Markov type property for Riesz
potentials. Furthermore, we give sufficient conditions on K (which are
satisfied if K is a smooth submanifold) so that a measure on K which satisfies
a mass-density condition will also satisfy this strong Bernstein-Markov
property.


title: Co-iterative augmented Hessian method for orbital optimization

abstract:
  Orbital optimization procedure is widely called in electronic structure
simulation. To efficiently find the orbital optimization solution, we developed
a new second order orbital optimization algorithm, co-iteration augmented
Hessian (CIAH) method. In this method, the orbital optimization is embedded in
the diagonalization procedure for augmented Hessian (AH) eigenvalue equation.
Approximations for Hessian matrix can be easily employed in this method to
improve the computational costs. We numerically performed the CIAH algorithm
with SCF convergence of 20 challenging systems and Boys localization of C60
molecule. We found that CIAH algorithm has better SCF convergence and less
computational costs than direct inversion iterative subspace (DIIS) algorithm.
The numerical tests suggest that CIAH is a stable, reliable and efficient
algorithm for orbital optimization problem.


title:
Counterfactual Reasoning about Intent for Interactive Navigation in
  Dynamic Environments

abstract:
  Many modern robotics applications require robots to function autonomously in
dynamic environments including other decision making agents, such as people or
other robots. This calls for fast and scalable interactive motion planning.
This requires models that take into consideration the other agent's intended
actions in one's own planning. We present a real-time motion planning framework
that brings together a few key components including intention inference by
reasoning counterfactually about potential motion of the other agents as they
work towards different goals. By using a light-weight motion model, we achieve
efficient iterative planning for fluid motion when avoiding pedestrians, in
parallel with goal inference for longer range movement prediction. This
inference framework is coupled with a novel distributed visual tracking method
that provides reliable and robust models for the current belief-state of the
monitored environment. This combined approach represents a computationally
efficient alternative to previously studied policy learning methods that often
require significant offline training or calibration and do not yet scale to
densely populated environments. We validate this framework with experiments
involving multi-robot and human-robot navigation. We further validate the
tracker component separately on much larger scale unconstrained pedestrian data
sets.


title:
Nature does not rely on long-lived electronic quantum coherence for
  photosynthetic energy transfer

abstract:
  During the first steps of photosynthesis, the energy of impinging solar
photons is transformed into electronic excitation energy of the
light-harvesting biomolecular complexes. The subsequent energy transfer to the
reaction center is understood in terms of exciton quasiparticles which move on
a grid of biomolecular sites on typical time scales less than 100 femtoseconds
(fs). Since the early days of quantum mechanics, this energy transfer is
described as an incoherent Forster hopping with classical site occupation
probabilities, but with quantum mechanically determined rate constants. This
orthodox picture has been challenged by ultrafast optical spectroscopy
experiments with the Fenna-Matthews-Olson protein in which interference
oscillatory signals up to 1.5 picoseconds were reported and interpreted as
direct evidence of exceptionally long-lived electronic quantum coherence. Here,
we show that the optical 2D photon echo spectra of this complex at ambient
temperature in aqueous solution do not provide evidence of any long-lived
electronic quantum coherence, but confirm the orthodox view of rapidly decaying
electronic quantum coherence on a time scale of 60 fs. Our results give no hint
that electronic quantum coherence plays any biofunctional role in real
photoactive biomolecular complexes. Since this natural energy transfer complex
is rather small and has a structurally well defined protein with the distances
between bacteriochlorophylls being comparable to other light-harvesting
complexes, we anticipate that this finding is general and directly applies to
even larger photoactive biomolecular complexes.


title:
Doping of Ga in antiferromagnetic semiconductor alpha-Cr2O3oxide and its
  effects on modified magnetic and electronic properties

abstract:
  The samples of Ga doped Cr2O3 oxide have been prepared using chemical
co-precipitation route. X-ray diffraction pattern and Raman spectra have
confirmed rhombohedral crystal structure with space group R3-C. Magnetic
measurement has indicated the dilution of antiferromagnetic (AFM) spin order in
Ga doped alpha-Cr2O3 system oxide, where the AFM transition temperature of bulk
alpha-Cr2O3 oxide at about 320 K has been suppressed and ferrimagnetic behavior
is observed from the analysis of the temperature dependence of magnetization
data below 350 K. Apart from Ga doping effect, the spin freezing (50 K-70 K)
and superparamagnetic behavior of the surface spins at lower temperatures,
typically below 50 K, have been exhibited due to nano-sized grains of the
samples. All the samples showed non-linear current-voltage (I-V)
characteristics. However, I-V characteristics of the Ga doped samples are
remarkably different from alpha-Cr2O3 sample. The I-V curves of Ga doped
samples have exhibited many unique electronic properties, e.g., bi-stable (low
resistance- LR and high resistance-HR) electronic states and negative
differential resistance (NDR). Optical absorption spectra revealed three
electronic transitions in the samples associated with band gap energy at about
2.67-2.81 eV, 1.91-2.11 eV, 1.28-1.35 eV, respectively.


title: Anisotropic permeability in deterministic lateral displacement arrays

abstract:
  We uncover anisotropic permeability in microfluidic deterministic lateral
displacement (DLD) arrays. A DLD array can achieve high-resolution bimodal
size-based separation of microparticles, including bioparticles, such as cells.
For an application with a given separation size, correct device operation
requires that the flow remains at a fixed angle to the obstacle array. We
demonstrate via experiments and lattice-Boltzmann simulations that subtle array
design features cause anisotropic permeability. Anisotropic permeability
indicates the microfluidic array's intrinsic tendency to induce an undesired
lateral pressure gradient. This can cause an inclined flow and therefore local
changes in the critical separation size. Thus, particle trajectories can become
unpredictable and the device useless for the desired separation task.
Anisotropy becomes severe for arrays with unequal axial and lateral gaps
between obstacle posts and highly asymmetric post shapes. Furthermore, of the
two equivalent array layouts employed with the DLD, the rotated-square layout
does not display intrinsic anisotropy. We therefore recommend this layout over
the easier-to-implement parallelogram layout. We provide additional guidelines
for avoiding adverse effects of anisotropy on the DLD.


title: Multi-wavelength study of the star-formation in the S237 H II region

abstract:
  We present a detailed multi-wavelength study of observations from X-ray,
near-infrared to centimeter wavelengths to probe the star formation processes
in the S237 region. Multi-wavelength images trace an almost sphere-like shell
morphology of the region, which is filled with the 0.5--2 keV X-ray emission.
The region contains two distinct environments - a bell-shaped cavity-like
structure containing the peak of 1.4 GHz emission at center, and elongated
filamentary features without any radio detection at edges of the sphere-like
shell - where {\it Herschel} clumps are detected. Using the 1.4 GHz continuum
and $^{12}$CO line data, the S237 region is found to be excited by a radio
spectral type of B0.5V star and is associated with an expanding H{\sc ii}
region. The photoionized gas appears to be responsible for the origin of the
bell-shaped structure. The majority of molecular gas is distributed toward a
massive {\it Herschel} clump (M$_{clump}$ $\sim$260 M$_{\odot}$), which
contains the filamentary features and has a noticeable velocity gradient. The
photometric analysis traces the clusters of young stellar objects (YSOs) mainly
toward the bell-shaped structure and the filamentary features. Considering the
lower dynamical age of the H\,{\sc ii} region (i.e. 0.2-0.8 Myr), these
clusters are unlikely to be formed by the expansion of the H\,{\sc ii} region.
Our results also show the existence of a cluster of YSOs and a massive clump at
the intersection of filamentary features, indicating that the collisions of
these features may have triggered cluster formation, similar to those found in
Serpens South region.


title:
Influences of Granular Constraints and Surface Effects on the
  Heterogeneity of Elastic, Superelastic, and Plastic Responses of
  Polycrystalline Shape Memory Alloys

abstract:
  Deformation heterogeneities within microstructures of polycrystalline shape
memory alloys (SMAs) during superelastic stressing are studied using both
experiments and simulations. In situ X-ray diffraction, specifically the
far-field high energy diffraction microscopy (ff-HEDM) technique was used to
non-destructively measure the grain-averaged statistics of position, crystal
orientation, elastic strain tensor and volume for hundreds of austenite grains
in a superelastically loaded nickel-titanium (NiTi) SMA. This experimental data
were also used to create a synthetic microstructure within a finite element
model. The development of intragranular stresses were then simulated during
tensile loading of the model using anisotropic elasticity. Driving forces for
phase transformation and slip were calculated from these stresses. The
grain-average responses of individual austenite crystals examined before and
after multiple stress-induced transformation events showed that grains at the
specimen interior carry more stress and plastically deform less than the
surface grains as the superelastic response shakes down. Examination of the
heterogeneity within individual grains showed that regions near grain
boundaries exhibit larger stress variation compared to the grain interiors.
This intragranular heterogeneity is more strongly driven by the constraints of
neighboring grains than the initial stress state and orientation of the
individual grains.


title: Singularity categories of deformations of Kleinian singularities

abstract:
  Let $G$ be a finite subgroup of $\text{SL}(2,\Bbbk)$ and let $R =
\Bbbk[x,y]^G$ be the coordinate ring of the corresponding Kleinian singularity.
In 1998, Crawley-Boevey and Holland defined deformations $\mathcal{O}^\lambda$
of $R$ parametrised by weights $\lambda$. In this paper, we determine the
singularity categories $\mathcal{D}_{\text{sg}}(\mathcal{O}^\lambda)$ of these
deformations, and show that they correspond to subgraphs of the Dynkin graph
associated to $R$. This generalises known results on the structure of
$\mathcal{D}_{\text{sg}}(R)$. We also provide a generalisation of the
intersection theory appearing in the geometric McKay correspondence to a
noncommutative setting.


title: Broad Context Language Modeling as Reading Comprehension

abstract:
  Progress in text understanding has been driven by large datasets that test
particular capabilities, like recent datasets for reading comprehension
(Hermann et al., 2015). We focus here on the LAMBADA dataset (Paperno et al.,
2016), a word prediction task requiring broader context than the immediate
sentence. We view LAMBADA as a reading comprehension problem and apply
comprehension models based on neural networks. Though these models are
constrained to choose a word from the context, they improve the state of the
art on LAMBADA from 7.3% to 49%. We analyze 100 instances, finding that neural
network readers perform well in cases that involve selecting a name from the
context based on dialogue or discourse cues but struggle when coreference
resolution or external knowledge is needed.


title: Spontaneous natural optical activity in disordered media

abstract:
  We demonstrate natural optical activity in disordered ensembles of non-chiral
plasmonic resonators. We show that the statistical distributions of rotatory
power and spatial dichroism are strongly dependent on the scattering mean free
path in diffusive random media. This result is explained in terms of the
intrinsic geometric chirality of disordered media, as they lack mirror
symmetry. We argue that chirality and natural optical activity of disordered
systems can be quantified by the standard deviation of both rotatory power and
spatial dichroism. Our results are based on microscopic electromagnetic wave
transport theory coupled to vectorial Green's matrix method for pointlike
scatterers, and are independently confirmed by full-wave simulations.


title: On Corpuscular Theory of Inflation

abstract:
  In order to go beyond the mean-field approximation, commonly used in the
inflationary computations, an identification of the quantum constituents of the
inflationary background is made. In particular, the homogeneous scalar field
configuration is represented as a Bose-Einstein condensate of the off-shell
inflaton degrees of freedom, with mass significantly screened by the
gravitational binding energy. The gravitational counterpart of the classical
background is considered to be a degenerate state of the off-shell longitudinal
gravitons with the frequency of the order of the Hubble scale. As a result, the
origin of the density perturbations in the slow-roll regime is identified as an
uncertainty in the position of the constituent inflatons. While in the regime
of eternal inflation, the scattering of the constituent gravitons becomes the
relevant source of the density perturbations. The gravitational waves, on the
other hand, originate from the annihilation of the constituent longitudinal
gravitons at all energy scales. This results in the quantum depletion of the
classical background. Leading to the upper bound on the number of e-folds,
after which the semiclassical description is expected to break down, which is
estimated to be of the order of the entropy of the initial Hubble patch.


title: Sphere systems, standard form, and cores of products of trees

abstract:
  We introduce the concept of a standard form for two embedded maximal sphere
systems in the doubled handlebody, and we prove an existence and uniqueness
result. In particular, we show that pairs of maximal sphere systems in the
doubled handlebody (up to homeomorphism) bijectively correspond to square
complexes satisfying a set of properties. This work is a variant on Hatcher's
normal form.


title: The forcing number of graphs with a given girth

abstract:
  In this paper, we study a dynamic coloring of the vertices of a graph $G$
that starts with an initial subset $S$ of colored vertices, with all remaining
vertices being non-colored. At each discrete time interval, a colored vertex
with exactly one non-colored neighbor forces this non-colored neighbor to be
colored. The initial set $S$ is called a forcing set of $G$ if, by iteratively
applying the forcing process, every vertex in $G$ becomes colored. The forcing
number, originally known as the \emph{zero forcing number}, and denoted $F(G)$,
of $G$ is the cardinality of a smallest forcing set of $G$. We study lower
bounds on the forcing number in terms of its minimum degree and girth, where
the girth $g$ of a graph is the length of a shortest cycle in the graph. Let
$G$ be a graph with minimum degree $\delta \ge 2$ and girth~$g \ge 3$. Davila
and Kenter [Theory and Applications of Graphs, Volume 2, Issue 2, Article 1,
2015] conjecture that $F(G) \ge \delta + (\delta-2)(g-3)$. This conjecture has
recently been proven for $g \le 6$. The conjecture is also proven when the
girth $g \ge 7$ and the minimum degree is sufficiently large. In particular, it
holds when $g = 7$ and $\delta \ge 481$, when $g = 8$ and $\delta \ge 649$,
when $g = 9$ and $\delta \ge 30$, and when $g = 10$ and $\delta \ge 34$. In
this paper, we prove the conjecture for $g \in \{7,8,9,10\}$ and for all values
of $\delta \ge 2$.


title:
Estimating the concentration of gold nanoparticles incorporated on
  Natural Rubber membranes using Multi-Level Starlet Optimal Segmentation

abstract:
  This study consolidates Multi-Level Starlet Segmentation (MLSS) and
Multi-Level Starlet Optimal Segmentation (MLSOS), techniques for
photomicrograph segmentation that use starlet wavelet detail levels to separate
areas of interest in an input image. Several segmentation levels can be
obtained using Multi-Level Starlet Segmentation; after that, Matthews
correlation coefficient (MCC) is used to choose an optimal segmentation level,
giving rise to Multi-Level Starlet Optimal Segmentation. In this paper, MLSOS
is employed to estimate the concentration of gold nanoparticles with diameter
around 47 nm, reducted on natural rubber membranes. These samples were used on
the construction of SERS/SERRS substrates and in the study of natural rubber
membranes with incorporated gold nanoparticles influence on Leishmania
braziliensis physiology. Precision, recall and accuracy are used to evaluate
the segmentation performance, and MLSOS presents accuracy greater than 88% for
this application.


title:
On the region of attraction of phase-locked states for swing equations
  on connected graphs with inhomogeneous dampings

abstract:
  We consider the synchronization problem of swing equations, a second-order
Kuramoto-type model, on connected networks with inhomogeneous dampings. This
was largely motivated by its relevance to the dynamics of power grids. We focus
on the estimate of the region of attraction of synchronous states which is a
central problem in the transient stability of power grids. In the recent
literature, D\"{o}rfler, Chertkov, and Bullo [Proc. Natl. Acad. Sci. USA, 110
(2013), pp. 2005-2010] found a condition for the synchronization in smart
grids. They pointed out that the region of attraction is an important unsolved
problem. In [SIAM J. Control Optim., 52 (2014), pp. 2482-2511], only a special
case was considered where the oscillators have homogeneous dampings and the
underlying graph has a diameter less than or equal to 2. There the analysis
heavily relies on these assumptions; however, they are too strict compared to
the real power networks. In this paper, we continue the study and derive an
estimate on the region of attraction of phase-locked states for lossless power
grids on connected graphs with inhomogeneous dampings. Our main strategy is
based on the gradient-like formulation and energy estimate. We refine the
assumptions by constructing a new energy functional which enables us to
consider such general settings.


title: Band gap modulation in polythiophene and polypyrrole-based systems

abstract:
  In this paper, the structural and electronic properties of polythiophene and
polyprrrole-based systems have been investigated using first-principles
calculations both in periodic and oligomer forms. Of particular interest is the
band gap modulation through substitutions and bilayer formation. Specifically,
S has been substituted by Se and Te in polythiophene, leading to polyseleophene
and polytellurophene, respectively, and N has been substituted by P and As in
polypyrrole. The values obtained of the binding energy suggest that all the
systems studied can be realized experimentally. Stacking (bilayer formation) of
pure polythiophene, polypyrrole and their derivatives leads to linear
suppression of the band gap or HOMO-LUMO gap as a function of the stacking.
Mixed bilayers, including one formed from polythiophene on top of polypyrrole,
have also been considered. Overall, a wide range of band gaps can be achieved
through substitutions and stacking. Hybrid (B3LYP) calculations also suggest
the same trend in the band gap as PBE calculations. Trends in the binding
energy are similar for both periodic and molecular calculations. In addition,
the $\Gamma$-point phonon calculation are performed in order to check the
stability of selected systems.


title:
Light-pressure experiments by P. N. Lebedev and modern problems of
  optomechanics and quantum optics

abstract:
  In connection with the 150-th Anniversary of P. N. Lebedev, we present
historical aspects of his scientific and organizing activity and recall his
famous experimental observations and proof of the existence of light pressure
along with other results that essentially influenced the development of physics
in Russia and in the whole world as well. We discuss the relationship of these
studies of electromagnetic waves and other kinds of vibrational phenomena
investigated by P. N. Lebedev to modern studies of the interaction of photons
with mirrors, gravitational waves, acoustic waves, nonstationary (dynamical)
Casimir effect of photon creation in resonators with vibrating boundaries, and
vibrations of voltage and current in superconducting circuits realizing the
states of qubits and qudits. We discuss the possibility of existence of the
nonstationary Casimir effect for gravitational waves and sound in liquid
helium.


title:
A Reanalysis of High Resolution XMM-Newton Data of V2491 Cyg Using
  Collisionally Ionized Hot Absorber Models

abstract:
  We present a reanalysis of XMM-Newton Reflection Grating Spectrometer data of
the classical nova V2491 Cyg obtained from two different pointings, 40 d and 50
d after outburst utilizing the SRON software SPEX version 2.05.04. We aim to
model absorption components using hot collisionally ionized absorber models
along with interstellar absorption (of gas and dust origin separately). We find
blackbody temperatures in a range 61-91 eV for the continuum yielding a white
dwarf mass of 1.15-1.3 M_sun. We derive two different hot absorber components
with blueshifts yielding 2900-3800 km/s for the first (day 40) and 2600-3600
km/s for the second observation 50 days after outburst consistent with
ejecta/wind speeds. The two collisionally ionized hot absorption components
have temperatures kT_1 =1.0-3.6 keV and kT_2 =0.4-0.87 keV with rms velocities
(sigma_v) 872 km/s and 56 km/s. These are consistent with shock temperatures in
the X-ray wavelengths. V2491 Cyg shows signature of H-burning with
underabundant carbon C/C_sun=0.3-0.5, and enhanced nitrogen N/N_sun=5-7 and
oxygen O/O_sun=16-43. We find the equivalent hydrogen column density of the hot
collisionally ionized absorbers in a range (0.6-18.0)x10^{23} cm^{-2} and
(2.0-5.3)x10^{23} cm^{-2} on days 40 and 50 after outburst, respectively. Our
fits yield the most adequate redchisq (range 1.8-2.9) up-to-date obtained for
the modeling of high resolution X-ray data of V2491 Cyg. An additional
photoionized absorber (third intrinsic absorber component) originating in the
shell/ejecta improves the model fits with redchisq in a range 1.7-2.5, but
shows only (1-0.1)% of the absorption by the collisionaly-ionized hot gas. Our
analysis reveals a second blackbody component on day 50 with effective
temperature 120-131 eV and effective radius about 10% of the WD which may
indicate the onset of magnetic accretion.


title: Minimum Riesz Energy Problem on the Hyperdisk

abstract:
  We consider the minimum Riesz $s$-energy problem on the unit disk $\mathbb
D:=\{(x_1,\ldots,x_d)\in\mathbb R^d: x_1=0, x_2^2+x_3^2+\ldots+x_d^2\leq 1\}$
in the Euclidean space $\mathbb R^d$, $d\geq 3$, immersed into a smooth
rotationally invariant external field $Q$. The charges are assumed to interact
via the Riesz potential $1/r^s$, with $d-3 < s < d-1$, where $r$ denotes the
Euclidean distance. We solve the problem by finding an explicit expression for
the extremal measure. We then consider applications to a monomial external
field and an external field generated by a positive point charge, located at
some distance above the disk on the polar axis. We obtain an equation
describing the critical height for the location of the point charge, which
guarantees that the support of the extremal measure occupies the whole disk
$\mathbb D$. We also show that under some mild restrictions on a general
external field the support of the extremal measure will have a ring structure.
Furthermore, we demonstrate how to reduce the problem of recovery of the
extremal measure in this case to a Fredholm integral equation of the second
kind.


title:
Inferring individual attributes from search engine queries and auxiliary
  information

abstract:
  Internet data has surfaced as a primary source for investigation of different
aspects of human behavior. A crucial step in such studies is finding a suitable
cohort (i.e., a set of users) that shares a common trait of interest to
researchers. However, direct identification of users sharing this trait is
often impossible, as the data available to researchers is usually anonymized to
preserve user privacy. To facilitate research on specific topics of interest,
especially in medicine, we introduce an algorithm for identifying a trait of
interest in anonymous users. We illustrate how a small set of labeled examples,
together with statistical information about the entire population, can be
aggregated to obtain labels on unseen examples. We validate our approach using
labeled data from the political domain.
  We provide two applications of the proposed algorithm to the medical domain.
In the first, we demonstrate how to identify users whose search patterns
indicate they might be suffering from certain types of cancer. In the second,
we detail an algorithm to predict the distribution of diseases given their
incidence in a subset of the population at study, making it possible to predict
disease spread from partial epidemiological data.


title: Topological phase in oxidized zigzag stanene nanoribbons

abstract:
  First-principles and semi-empirical tight binding calculations were performed
to understand the adsorption of oxygen on the surface of two dimensional (2D)
and zigzag stanene nano-ribbons. The intrinsic spin-orbit interaction is
considered in the Kane-Mele tight binding model. The adsorption of an oxygen
atom or molecule on the 2D stanene opens an electronic energy band gap. We
investigate the helical edge states and topological phase in the pure zigzag
stanene nano-ribbons. The adsorption of oxygen atoms on the zigzag stanene
nano-ribbons deforms the helical edge states at the Fermi level which causes
topological (non-trivial) to trivial phase transition. The structural stability
of the systems is checked by performing $\Gamma$-point phonon calculations. The
adsorption of an oxygen atom or molecule on the 2D staneneSpecific arrangements
of adsorbed oxygen atoms on the surface of zigzag stanene nano-ribbons conserve
the topological phase which has potential applications in future
nano-electronic devices.


title:
Temperedness of measures defined by polynomial equations over local
  fields

abstract:
  We investigate the asymptotic growth of the canonical measures on the fibers
of morphisms between vector spaces over local fields of arbitrary
characteristic. For non-archimedean local fields we use a version of the
{\L}ojasiewicz inequality (\cite{lojasiewicz1959},
\cite{hormander1958division}) which follows from Greenberg
\cite{greenberg1966rational}, \cite{bollaerts1990estimate}, together with the
theory of the Brauer group of local fields to construct definite forms of
arbitrarily high degree, and to transfer questions at infinity to questions
near the origin. We then use these to generalize results of H{\"o}rmander
\cite{hormander1958division} on estimating the growth of polynomials at
infinity in terms of the distance to their zero loci. Specifically, when a
fiber corresponds to a non-critical value which is stable, i.e. remains
non-critical under small perturbations, we show that the canonical measure on
the fiber is tempered, which generalizes results of Igusa and Raghavan
\cite{igusa1978lectures}, and Virtanen and Weisbart
\cite{virtanen2014elementary}.


title: New Liftable Classes for First-Order Probabilistic Inference

abstract:
  Statistical relational models provide compact encodings of probabilistic
dependencies in relational domains, but result in highly intractable graphical
models. The goal of lifted inference is to carry out probabilistic inference
without needing to reason about each individual separately, by instead treating
exchangeable, undistinguished objects as a whole. In this paper, we study the
domain recursion inference rule, which, despite its central role in early
theoretical results on domain-lifted inference, has later been believed
redundant. We show that this rule is more powerful than expected, and in fact
significantly extends the range of models for which lifted inference runs in
time polynomial in the number of individuals in the domain. This includes an
open problem called S4, the symmetric transitivity model, and a first-order
logic encoding of the birthday paradox. We further identify new classes S2FO2
and S2RU of domain-liftable theories, which respectively subsume FO2 and
recursively unary theories, the largest classes of domain-liftable theories
known so far, and show that using domain recursion can achieve exponential
speedup even in theories that cannot fully be lifted with the existing set of
inference rules.


title: Modelling avalanches in martensites

abstract:
  Solids subject to continuous changes of temperature or mechanical load often
exhibit discontinuous avalanche-like responses. For instance, avalanche
dynamics have been observed during plastic deformation, fracture, domain
switching in ferroic materials or martensitic transformations. The statistical
analysis of avalanches reveals a very complex scenario with a distinctive lack
of characteristic scales. Much effort has been devoted in the last decades to
understand the origin and ubiquity of scale-free behaviour in solids and many
other systems. This chapter reviews some efforts to understand the
characteristics of avalanches in martensites through mathematical modelling.


title: Fano stability diagram of a symmetric triple quantum dot

abstract:
  The Fano factor stability diagram of a C$_{3v}$ symmetric triangular quantum
dot is analysed for increasing electron fillings $N$. At low filling,
conventional Poissonian and sub-Poissonian behavior is found. At larger
filling, $N\ge 2$, a breaking of the electron-hole symmetry is manifested in
super-Poissonian noise with a peculiar bias voltage dependence of the Fano
factor at Coulomb and interference blockade. An analysis of the Fano map
unravels a nontrivial electron bunching mechanism arising from the presence of
degenerate many-body states combined with orbital interference and Coulomb
interactions. An expression for the associated dark states is provided for
generic $N$.


title:
Distinct scaling behaviors of giant electrocaloric cooling performance
  in low-dimensional organic, relaxor and anti-ferroelectrics

abstract:
  Electrocaloric (EC) materials show promise in eco-friendly solid-state
refrigeration and integrable on-chip thermal management. While direct
measurement of EC thin-films still remains challenging, a generic theoretical
framework for quantifying the cooling properties of rich EC materials including
normal-, relaxor-, organic- and anti-ferroelectrics is imperative for
exploiting new flexible and room-temperature cooling alternatives. Here, we
present a versatile theory that combines Master equation with Maxwell relations
and analytically relates the macroscopic cooling responses in EC materials with
the intrinsic diffuseness of phase transitions and correlation characteristics.
Under increased electric fields, both EC entropy and adiabatic temperature
changes increase quadratically initially, followed by further linear growth and
eventual gradual saturation. The upper bound of entropy change (dS_max) is
limited by distinct correlation volumes (V_cr) and transition diffuseness. The
linearity between V_cr and the transition diffuseness is emphasized, while
dS_max=300 kJ/(K.m3) is obtained for Pb0.8Ba0.2ZrO3. The dS_max in
antiferroelectric Pb0.95Zr0.05TiO3, Pb0.8Ba0.2ZrO3 and polymeric ferroelectrics
scales proportionally with V_cr^(-2.2), owing to the one-dimensional structural
constraint on lattice-scale depolarization dynamics; whereas dS_max in relaxor
and normal ferroelectrics scales as dS_max ~ V_cr^(-0.37), which tallies with a
dipolar interaction exponent of 2/3 in EC materials and the well-proven
fractional dimensionality of 2.5 for ferroelectric domain walls.


title: Dusty globules in the Crab Nebula

abstract:
  From existing broad-band images obtained with the Hubble Space Telescope, we
located 92 globules, for which we derived positions, dimensions, orientations,
extinctions, masses, proper motions, and their distributions. The globules have
mean radii ranging from 400 to 2000 AU and are not resolved in current infrared
images of the nebula. The extinction law for dust grains in these globules
matches a normal interstellar extinction law. Derived masses of dust range from
1 to 60 x 10^(-6) solar masses, and the total mass contained in globules
constitute a fraction of approximately 2% or less of the total dust content of
the nebula. The globules are spread over the outer part of the nebula, and a
fraction of them coincide in position with emission filaments, where we find
elongated globules that are aligned with these filaments. Only 10% of the
globules are coincident in position with the numerous H2-emitting knots found
in previous studies. All globules move outwards from the centre with
transversal velocities of 60 to 1600 km/s, along with the general expansion of
the remnant. We discuss various hypotheses for the formation of globules in the
Crab Nebula.


title:
Body movement to sound interface with vector autoregressive hierarchical
  hidden Markov models

abstract:
  Interfacing a kinetic action of a person to an action of a machine system is
an important research topic in many application areas. One of the key factors
for intimate human-machine interaction is the ability of the control algorithm
to detect and classify different user commands with shortest possible latency,
thus making a highly correlated link between cause and effect. In our research,
we focused on the task of mapping user kinematic actions into sound samples.
The presented methodology relies on the wireless sensor nodes equipped with
inertial measurement units and the real-time algorithm dedicated for early
detection and classification of a variety of movements/gestures performed by a
user. The core algorithm is based on the approximate Bayesian inference of
Vector Autoregressive Hierarchical Hidden Markov Models (VAR-HHMM), where
models database is derived from the set of motion gestures. The performance of
the algorithm was compared with an online version of the K-nearest neighbours
(KNN) algorithm, where we used offline expert based classification as the
benchmark. In almost all of the evaluation metrics (e.g. confusion matrix,
recall and precision scores) the VAR-HHMM algorithm outperformed KNN.
Furthermore, the VAR-HHMM algorithm, in some cases, achieved faster movement
onset detection compared with the offline standard. The proposed concept,
although envisioned for movement-to-sound application, could be implemented in
other human-machine interfaces.


title: Graviton resonance phenomenology and a pNGB Higgs at the LHC

abstract:
  We present an effective description of a spin two massive state and a pseudo
Nambu-Goldstone boson Higgs in a two site model. Using this framework we model
the spin two state as a massive graviton and we study its phenomenology at the
LHC. We find that a reduced set of parameters can describe the most important
features of this scenario. We address the question of which channel is the most
sensitive to detect this graviton. Instead of designing search strategies to
estimate the significance in each channel, we compare the ratio of our
theoretical predictions to the limits set by available experimental searches
for all the decay channels and as a function of the free parameters in the
model. We discuss the phenomenological details contained in the outcome of this
simple procedure. The results indicate that, for the studied masses between 0.5
and 3 TeV, the channels to look for such a graviton resonance are mainly $ZZ$,
$WW$ and $\gamma\gamma$. This is the case even though top and bottom quarks
dominate the branching ratios, since their experimental sensitivity is not as
good as the one of the electro-weak gauge bosons. We find that as the graviton
mass increases, the $ZZ$ and $WW$ channels become more important because of its
relatively better enhancement over background, mainly due to fat jet
techniques. We determine the region of the parameter space that has already
been excluded and the reach for the LHC next stages. We also estimate the size
of the loop-induced contributions to the production and decay of the graviton,
and show in which region of the parameter space their effects are relevant for
our analysis.


title:
Fairness Beyond Disparate Treatment & Disparate Impact: Learning
  Classification without Disparate Mistreatment

abstract:
  Automated data-driven decision making systems are increasingly being used to
assist, or even replace humans in many settings. These systems function by
learning from historical decisions, often taken by humans. In order to maximize
the utility of these systems (or, classifiers), their training involves
minimizing the errors (or, misclassifications) over the given historical data.
However, it is quite possible that the optimally trained classifier makes
decisions for people belonging to different social groups with different
misclassification rates (e.g., misclassification rates for females are higher
than for males), thereby placing these groups at an unfair disadvantage. To
account for and avoid such unfairness, in this paper, we introduce a new notion
of unfairness, disparate mistreatment, which is defined in terms of
misclassification rates. We then propose intuitive measures of disparate
mistreatment for decision boundary-based classifiers, which can be easily
incorporated into their formulation as convex-concave constraints. Experiments
on synthetic as well as real world datasets show that our methodology is
effective at avoiding disparate mistreatment, often at a small cost in terms of
accuracy.


title: All silicon Josephson junctions

abstract:
  We have realised laser-doped all-silicon superconducting (S)/ normal metal
(N) bilayers of tunable thickness and dopant concentration. We observed a
strong reduction of the bilayers critical temperature when increasing the
normal metal thickness, a signature of the highly transparent S/N interface
associated to the epitaxial sharp laser doping profile. We extracted the
interface resistance by fitting with the linearised Usadel equations,
demonstrating a reduction of one order of magnitude from previous
superconductor/doped Si interfaces. In this well controlled crystalline system
we exploited the low resistance S/N interfaces to elaborate all-silicon lateral
SNS Josephson junctions with long range proximity effect. Their dc transport
properties, such as the critical and retrapping currents, could be well
understood in the diffusive regime. Furthermore, this work lead to the
estimation of important parameters in ultra-doped superconducting Si, such as
the Fermi velocity, the coherence length, or the electron-phonon coupling
constant, fundamental to conceive an all-silicon superconducting electronics.


title: Chabauty limits of algebraic groups acting on trees

abstract:
  Given a locally finite leafless tree $ T $, various algebraic groups over
local fields might appear as closed subgroups of $ \text{Aut} (T)$. We show
that the set of closed cocompact subgroups of $ \text{Aut} (T)$ that are
isomorphic to a quasi-split simple algebraic group is a closed subset of the
Chabauty space of $ \text{Aut} (T)$. This is done via a study of the integral
Bruhat$-$Tits model of $ \text{SL}_2 $ and $ \text{SU}_3^{L/K} $, that we carry
on over arbitrary local fields, without any restriction on the (residue)
characteristic. In particular, we show that in residue characteristic $ 2 $,
the Tits index of simple algebraic subgroups of $ \text{Aut} (T)$ is not always
preserved under Chabauty limits.


title:
Smooth and sharp creation of a pointlike source for a
  $(3+1)$-dimensional quantum field

abstract:
  We analyse the smooth and sharp creation of a pointlike source for a
quantised massless scalar field in $(3+1)$-dimensional Minkowski spacetime, as
a model for the breakdown of correlations that has been proposed to occur at
the horizon of an evaporating black hole. The creation is implemented by a
time-dependent self-adjointness parameter at the excised spatial origin. In a
smooth creation, the renormalised energy density $\langle T_{00} \rangle$ is
well defined away from the source, but it is unbounded both above and below:
the outgoing pulse contains an infinite negative energy, while a cloud of
infinite positive energy lingers near the fully-formed source. In the sharp
creation limit, $\langle T_{00} \rangle$ diverges everywhere in the timelike
future of the creation event, and so does the response of an Unruh-DeWitt
detector that operates in the timelike future of the creation event. The source
creation is significantly more singular than the corresponding process in $1+1$
dimensions, analysed previously, and it may be sufficiently singular to break
quantum correlations as proposed in a black hole spacetime.


title:
Second main theorem for meromorphic mappings with moving hypersurfaces
  in subgeneral position

abstract:
  Let $f$ be an algebraically nondegenerate meromorphic mapping from $\mathbb
C^m$ into $\mathbb P^n(\mathbb C)$ and let $Q_1,...,Q_q$ be $q$ hypersurfaces
in $\mathbb P^n(\mathbb C)$ of degree $d_i$, in $N-$subgeneral position. In
this paper, we will prove that, for every $\epsilon >0$, there exists a
positive integer $M$ such that $$||\ (q-(N-n+1)(n+1)-\epsilon)
T_f(r)\le\sum_{i=1}^q\frac{1}{d_i}N^{[M]}(r,f^*Q_i)+o(T_f(r)).$$ Moreover, an
explicit estimate for $M$ is given. Our result is an extension of the previous
second main theorem for the mappings and moving hyperplanes or moving
hypersurfaces.


title: Shapes of Auslander-Reiten Triangles

abstract:
  Our main theorem classifies the Auslander-Reiten triangles according to
properties of the morphisms involved. As a consequence, we are able to compute
the mapping cone of an irreducible morphism. We finish by showing a technique
for constructing the connecting component of the derived category of any tilted
algebra. In particular we obtain a technique for constructing the derived
category of any tilted algebra of finite representation type.


title: Sections of the Matsumoto-Cadavid-Korkmaz Lefschetz fibration

abstract:
  We give a maximal set of disjoint $(-1)$-sections of the well-known Lefschetz
fibration constructed by Matsumoto, Cadavid and Korkmaz. In fact, we obtain
several such sets for a fixed genus, which implies that the
Matsumoto-Cadavid-Korkmaz Lefschetz fibration has more than one supporting
minimal Lefschetz pencils. We also determine the diffeomorphism types of the
obtained supporting minimal Lefschetz pencils.


title: Model category of marked objects

abstract:
  For every functor $\mathcal{F} : \mathcal{K} \to \mathbf{C}$, where
$\mathcal{K}$ is a small category and $\mathbf{C}$ is a model category which
satisfies some mild hypotheses, we define a model category $\mathbf{C}^m$ of
$\mathcal{K}$-marked objects of $\mathbf{C}$. We consider an application of
this construction to the category of simplicial sets with the Joyal model
structure. Marked simplicial sets can be thought of as $(\infty,1)$-categories
with some additional structure which depends on $\mathcal{F}$. In particular,
we construct a model category of quasi-categories which have limits of all
diagrams of any given shape.


title: Disformal transformations as a change of units

abstract:
  A disformal transformation is a very useful tool to analyze a general
effective theory description of inflation. It can for example be used to set
the tensor sound speed to unity, such that the tensor power spectrum only
depends on the Hubble parameter. However, the disformal transformation has also
led to quite some confusion in recent literature. We hope to clarify that
confusion by pointing out that a disformal transformation is nothing else than
a change of units. We show how everything that can be achieved by a (possibly
time-dependent) disformal transformation, equally follows from the equivalent
change of units, up to all orders in perturbation theory. We also comment on
the sensitivity of the tensor power spectrum to a non-standard tensor speed of
sound.


title: A Proposed Algorithm for Minimum Vertex Cover Problem and its Testing

abstract:
  The paper presents an algorithm for minimum vertex cover problem, which is an
NP-Complete problem. The algorithm computes a minimum vertex cover of each
input simple graph. Tested by the attached MATLAB programs, Stage 1 of the
algorithm is applicable to, i.e., yields a proved minimum vertex cover for,
about 99.99% of the tested 610,000 graphs of order 16 and 99.67% of the tested
1,200 graphs of order 32, and Stage 2 of the algorithm is applicable to all of
the above tested graphs. All of the tested graphs are randomly generated graphs
of random "edge density" or in other words, random probability of each edge. It
is proved that Stage 1 and Stage 2 of the algorithm run in $O(n^{5+logn})$ and
$O(n^{3(5+logn)/2})$ time respectively, where $n$ is the order of input graph.
Because there is no theoretical proof yet that Stage 2 is applicable to all
graphs, further stages of the algorithm are proposed, which are in a general
form that is consistent with Stages 1 and 2.


title: Distraction-Based Neural Networks for Document Summarization

abstract:
  Distributed representation learned with neural networks has recently shown to
be effective in modeling natural languages at fine granularities such as words,
phrases, and even sentences. Whether and how such an approach can be extended
to help model larger spans of text, e.g., documents, is intriguing, and further
investigation would still be desirable. This paper aims to enhance neural
network models for such a purpose. A typical problem of document-level modeling
is automatic summarization, which aims to model documents in order to generate
summaries. In this paper, we propose neural models to train computers not just
to pay attention to specific regions and content of input documents with
attention models, but also distract them to traverse between different content
of a document so as to better grasp the overall meaning for summarization.
Without engineering any features, we train the models on two large datasets.
The models achieve the state-of-the-art performance, and they significantly
benefit from the distraction modeling, particularly when input documents are
long.


title:
Classical spin liquid instability driven by off-diagonal exchange in
  strong spin-orbit magnets

abstract:
  We show that the off-diagonal exchange anisotropy drives Mott insulators with
strong spin-orbit coupling to a classical spin liquid regime, characterized by
an infinite number of ground states and Ising variables living on closed or
open strings. Depending on the sign of the anisotropy, quantum fluctuations
either fail to lift the degeneracy down to very low temperatures, or select
non-collinear magnetic states with unconventional spin correlations. The
results apply to all 2D and 3D tri-coordinated materials with bond-directional
anisotropy, and provide a consistent interpretation of the suppression of the
x-ray magnetic circular dichroism signal reported recently for
$\beta$-Li$_2$IrO$_3$ under pressure.


title: Mapping class groups are not linear in positive characteristic

abstract:
  For $\Sigma$ an orientable surface of finite topological type having genus at
least 3 (possibly closed or possibly with any number of punctures or boundary
components), we show that the mapping class group $Mod(\Sigma)$ has no faithful
linear representation in any dimension over any field of positive
characteristic.


title: Bayesian latent structure discovery from multi-neuron recordings

abstract:
  Neural circuits contain heterogeneous groups of neurons that differ in type,
location, connectivity, and basic response properties. However, traditional
methods for dimensionality reduction and clustering are ill-suited to
recovering the structure underlying the organization of neural circuits. In
particular, they do not take advantage of the rich temporal dependencies in
multi-neuron recordings and fail to account for the noise in neural spike
trains. Here we describe new tools for inferring latent structure from
simultaneously recorded spike train data using a hierarchical extension of a
multi-neuron point process model commonly known as the generalized linear model
(GLM). Our approach combines the GLM with flexible graph-theoretic priors
governing the relationship between latent features and neural connectivity
patterns. Fully Bayesian inference via P\'olya-gamma augmentation of the
resulting model allows us to classify neurons and infer latent dimensions of
circuit organization from correlated spike trains. We demonstrate the
effectiveness of our method with applications to synthetic data and
multi-neuron recordings in primate retina, revealing latent patterns of neural
types and locations from spike trains alone.


title: Recurrent switching linear dynamical systems

abstract:
  Many natural systems, such as neurons firing in the brain or basketball teams
traversing a court, give rise to time series data with complex, nonlinear
dynamics. We can gain insight into these systems by decomposing the data into
segments that are each explained by simpler dynamic units. Building on
switching linear dynamical systems (SLDS), we present a new model class that
not only discovers these dynamical units, but also explains how their switching
behavior depends on observations or continuous latent states. These "recurrent"
switching linear dynamical systems provide further insight by discovering the
conditions under which each unit is deployed, something that traditional SLDS
models fail to do. We leverage recent algorithmic advances in approximate
inference to make Bayesian inference in these models easy, fast, and scalable.


title:
Beats and Expansion of Two-Component Bose-Einstein Condensates in the
  Thomas-Fermi Limit

abstract:
  A unique feature of multi-component BECs is the possibility of beating
frequencies in collective oscillations. We analytically determine this beating
frequency for the two-component BEC in one-dimension. We also show that the
Thomas-Fermi approximation, where the quantum pressure is neglected, describes
well the expansion of the two-component condensate released from an harmonic
trap.


title: Algebraic renormalisation of regularity structures

abstract:
  We give a systematic description of a canonical renormalisation procedure of
stochastic PDEs containing nonlinearities involving generalised functions. This
theory is based on the construction of a new class of regularity structures
which comes with an explicit and elegant description of a subgroup of their
group of automorphisms. This subgroup is sufficiently large to be able to
implement a version of the BPHZ renormalisation prescription in this context.
This is in stark contrast to previous works where one considered regularity
structures with a much smaller group of automorphisms, which lead to a much
more indirect and convoluted construction of a renormalisation group acting on
the corresponding space of admissible models by continuous transformations. Our
construction is based on bialgebras of decorated coloured forests in
cointeraction. More precisely, we have two Hopf algebras in cointeraction,
coacting jointly on a vector space which represents the generalised functions
of the theory. Two twisted antipodes play a fundamental role in the
construction and provide a variant of the algebraic Birkhoff factorisation that
arises naturally in perturbative quantum field theory.


title: Kissing Cuisines: Exploring Worldwide Culinary Habits on the Web

abstract:
  Food and nutrition occupy an increasingly prevalent space on the web, and
dishes and recipes shared online provide an invaluable mirror into culinary
cultures and attitudes around the world. More specifically, ingredients,
flavors, and nutrition information become strong signals of the taste
preferences of individuals and civilizations. However, there is little
understanding of these palate varieties. In this paper, we present a
large-scale study of recipes published on the web and their content, aiming to
understand cuisines and culinary habits around the world. Using a database of
more than 157K recipes from over 200 different cuisines, we analyze
ingredients, flavors, and nutritional values which distinguish dishes from
different regions, and use this knowledge to assess the predictability of
recipes from different cuisines. We then use country health statistics to
understand the relation between these factors and health indicators of
different nations, such as obesity, diabetes, migration, and health
expenditure. Our results confirm the strong effects of geographical and
cultural similarities on recipes, health indicators, and culinary preferences
across the globe.


title:
Translation functors and decomposition numbers for the periplectic Lie
  superalgebra $\mathfrak{p}(n)$

abstract:
  We study the category $\mathcal{F}_n$ of finite-dimensional integrable
representations of the periplectic Lie superalgebra $\mathfrak{p}(n)$. We
define an action of the Temperley--Lieb algebra with infinitely many generators
and defining parameter $0$ on the category $\mathcal{F}_n$ by translation
functors. We also introduce combinatorial tools, called weight diagrams and
arrow diagrams for $\mathfrak{p}(n)$ resembling those for $\mathfrak{gl}(m|n)$.
Using the Temperley--Lieb algebra action and the combinatorics of weight and
arrow diagrams, we then calculate the multiplicities of standard and costandard
modules in indecomposable projective modules and classify the blocks of
$\mathcal{F}_n$. We also prove that indecomposable projective modules in this
category are multiplicity-free.


title: Limits to the presence of transiting circumbinary planets in CoRoT data

abstract:
  The CoRoT mission during its flight-phase 2007-2012 delivered the
light-curves for over 2000 eclipsing binaries. Data from the Kepler mission
have proven the existence of several transiting circumbinary planets. Albeit
light-curves from CoRoT have typically lower precision and shorter coverage,
CoRoT's number of targets is similar to Kepler, and some of the known
circumbinary planets could potentially be detected in CoRoT data as well. The
aim of this work has been a revision of the entire CoRoT data-set for the
presence of circumbinary planets, and the derivation of limits to the
abundances of such planets. We developed a code which removes the light curve
of the eclipsing binaries and searches for quasi-periodic transit-like features
in a light curve after removal of binary eclipses and instrumental features.
The code needs little information on the sample systems and can be used for
other space missions as well, like Kepler, K2, TESS and PLATO. The code is
broad in the requirements leading to detections, but was tuned to deliver an
amount of detections that is manageable in a subsequent, mainly visual,
revision about their nature. In the CoRoT sample we identified three planet
candidates whose transits would have arisen from a single pass across the
central binary. No candidates remained however with transit events from
multiple planetary orbits. We calculated the upper limits for the number of
Jupiter, Saturn and Neptune sized planets in co-planar orbits for different
orbital period ranges. We found that there are much less giant planets in
short-periodic orbits around close binary systems than around single stars.


title: On the Higher-Spin Spectrum in Large N Chern-Simons Vector Models

abstract:
  Chern-Simons gauge theories coupled to massless fundamental scalars or
fermions define interesting non-supersymmetric 3d CFTs that possess approximate
higher-spin symmetries at large N. In this paper, we compute the scaling
dimensions of the higher-spin operators in these models, to leading order in
the 1/N expansion and exactly in the 't Hooft coupling. We obtain these results
in two independent ways: by using conformal symmetry and the classical
equations of motion to fix the structure of the current non-conservation, and
by a direct Feynman diagram calculation. The full dependence on the 't Hooft
coupling can be restored by using results that follow from the weakly broken
higher-spin symmetry. This analysis also allows us to obtain some explicit
results for the non-conserved, parity-breaking structures that appear in planar
three-point functions of the higher-spin operators. At large spin, we find that
the anomalous dimensions grow logarithmically with the spin, in agreement with
general expectations. This logarithmic behavior disappears in the strong
coupling limit, where the anomalous dimensions turn into those of the critical
O(N) or Gross-Neveu models, in agreement with the conjectured 3d bosonization
duality.


title:
Estimating the Size of a Large Network and its Communities from a Random
  Sample

abstract:
  Most real-world networks are too large to be measured or studied directly and
there is substantial interest in estimating global network properties from
smaller sub-samples. One of the most important global properties is the number
of vertices/nodes in the network. Estimating the number of vertices in a large
network is a major challenge in computer science, epidemiology, demography, and
intelligence analysis. In this paper we consider a population random graph G =
(V;E) from the stochastic block model (SBM) with K communities/blocks. A sample
is obtained by randomly choosing a subset W and letting G(W) be the induced
subgraph in G of the vertices in W. In addition to G(W), we observe the total
degree of each sampled vertex and its block membership. Given this partial
information, we propose an efficient PopULation Size Estimation algorithm,
called PULSE, that correctly estimates the size of the whole population as well
as the size of each community. To support our theoretical analysis, we perform
an exhaustive set of experiments to study the effects of sample size, K, and
SBM model parameters on the accuracy of the estimates. The experimental results
also demonstrate that PULSE significantly outperforms a widely-used method
called the network scale-up estimator in a wide variety of scenarios. We
conclude with extensions and directions for future work.


title:
Young Stellar Clusters Containing Massive Young Stellar Objects in the
  VVV Survey

abstract:
  The purpose of this research is to study the connection of global properties
of eight young stellar clusters projected in the Vista Variables in the Via
Lactea (VVV) ESO Large Public Survey disk area and their young stellar object
population. The analysis in based on the combination of spectroscopic
parallax-based reddening and distance determinations with main sequence and
pre-main sequence ishochrone fitting to determine the basic parameters
(reddening, age, distance) of the sample clusters. The lower mass limit
estimations show that all clusters are low or intermediate mass (between 110
and 1800 Mo), the slope Gamma of the obtained present-day mass functions of the
clusters is close to the Kroupa initial mass function. On the other hand, the
young stellar objects in the surrounding cluster's fields are classified by low
resolution spectra, spectral energy distribution fit with theoretical
predictions, and variability, taking advantage of multi-epoch VVV observations.
All spectroscopically confirmed young stellar objects (except one) are found to
be massive (more than 8 Mo). Using VVV and GLIMPSE color-color cuts we have
selected a large number of new young stellar object candidates, which are
checked for variability and 57% are found to show at least low-amplitude
variations. In few cases it was possible to distinguish between YSO and AGB
classification on the basis of the light curves.


title:
Cryptanalysis of a Classical chaos-based cryptosystem with some quantum
  cryptography features

abstract:
  The application of synchronization theory to build up new cryptosystems has
been a hot topic during the last two decades. In this paper we analyze a recent
proposal in this field. We pinpoint the main limitations of the software
implementation of chaos-based systems designed on the grounds of
synchronization theory. In addition, we show that the cryptosystem under
evaluation possesses serious security problems that imply a clear reduction of
the key space.


title: Gradual Typing in an Open World

abstract:
  Gradual typing combines static and dynamic typing in the same language,
offering the benefits of both to programmers. Static typing provides error
detection and strong guarantees while dynamic typing enables rapid prototyping
and flexible programming idioms. For programmers to fully take advantage of a
gradual type system, however, they must be able to trust their type
annotations, and so runtime checks must be performed at the boundaries of
static and dynamic code to ensure that static types are respected. Higher order
and mutable values cannot be completely checked at these boundaries, and so
additional checks must be performed at their use sites. Traditionally, this has
been achieved by installing wrappers or proxies on such values that moderate
the flow of data between static and dynamic, but these can cause problems if
the language supports comparison of object identity or has a foreign function
interface.
  Reticulated Python is a gradually typed variant of Python implemented via a
source-to-source translator for Python 3. It implements a proxy-free
alternative design named transient casts. This paper presents a formal
semantics for transient casts and shows that not only are they sound, but they
work in an open-world setting in which the Reticulated translator has only been
applied to some of the program; the rest is untranslated Python. We formalize
this open world soundness property and use Coq to prove that it holds for
Anthill Python, a calculus that models Reticulated Python.


title: Non-diffusive Lattice Thermal Transport in Si-Ge Alloy Nanowires

abstract:
  We present a calculation of the lattice thermal conductivity of Si-Ge
nanowires (NWs), based on solving the Boltzmann transport equation by the Monte
Carlo method of sampling the phonon mean free paths. We augment the previous
work with the full phonon dispersion and a partially diffuse momentum-dependent
specularity model for boundary roughness scattering. We find that phonon
flights are comprised of a mix of long free-flights over several {\mu}m
interrupted by bursts of short flights, resulting in a heavy tailed
distribution of flight lengths, typically encountered in L\'{e}vy walk
dynamics. Consequently, phonon transport in Si-Ge NWs is neither entirely
ballistic nor diffusive; instead, it falls into an intermediate regime called
superdiffusion where thermal conductivity scales with the length of the NW as
$\kappa \propto L^{\alpha}$ with the exponent of length dependence
$\alpha\approx 0.33$ over a broad range of wire lengths 10 nm$<L<$10 $\mu$m
regardless of diameter and roughness. We conclude that thermal conductivity in
Si-Ge alloy NWs is length-dependent up to 10 $\mu$m and therefore can be tuned
for thermoelectric applications.


title:
Interacting fermionic symmetry-protected topological phases in two
  dimensions

abstract:
  We classify and construct models for two-dimensional (2D) interacting
fermionic symmetry-protected topological (FSPT) phases with general finite
Abelian unitary symmetry $G_f$. To obtain the classification, we couple the
FSPT system to a dynamical discrete gauge field with gauge group $G_f$ and
study braiding statistics in the resulting gauge theory. Under reasonable
assumptions, the braiding statistics data allows us to infer a potentially
complete classification of 2D FSPT phases with Abelian symmetry. The FSPT
models that we construct are simple stacks of the following two kinds of
existing models: (i) free-fermion models and (ii) models obtained through
embedding of bosonic symmetry-protected topological (BSPT) phases.
Interestingly, using these two kinds of models, we are able to realize almost
all FSPT phases in our classification, except for one class. We argue that this
exceptional class of FSPT phases can never be realized through models (i) and
(ii), and therefore can be thought of as intrinsically interacting and
intrinsically fermionic. The simplest example of this class is associated with
$\mathbb Z_4^f\times\mathbb Z_4\times\mathbb Z_4$ symmetry. We show that all 2D
FSPT phases with a finite Abelian symmetry of the form $ \mathbb Z_2^f\times G$
can be realized through the above models (i), or (ii), or a simple stack of
them. Finally, we study the stability of BSPT phases when they are embedded
into fermionic systems.


title:
Detecting the gravitational wave background from primordial black hole
  dark matter

abstract:
  The black hole merging rates inferred after the gravitational-wave detection
by Advanced LIGO/VIRGO and the relatively high mass of the progenitors are
consistent with models of dark matter made of massive primordial black holes
(PBH). PBH binaries emit gravitational waves in a broad range of frequencies
that will be probed by future space interferometers (LISA) and pulsar timing
arrays (PTA). The amplitude of the stochastic gravitational-wave background
expected for PBH dark matter is calculated taking into account various effects
such as initial eccentricity of binaries, PBH velocities, mass distribution and
clustering. It allows a detection by the LISA space interferometer, and
possibly by the PTA of the SKA radio-telescope. Interestingly, one can
distinguish this background from the one of non-primordial massive binaries
through a specific frequency dependence, resulting from the maximal impact
parameter of binaries formed by PBH capture, depending on the PBH velocity
distribution and their clustering properties. Moreover, we find that the
gravitational wave spectrum is boosted by the width of PBH mass distribution,
compared with that of the monochromatic spectrum. The current PTA constraints
already rule out broad-mass PBH models covering more than three decades of
masses, but evading the microlensing and CMB constraints due to clustering.


title:
Spatially Resolved Electronic Properties of Single-Layer WS$_2$ on
  Transition Metal Oxides

abstract:
  There is a substantial interest in the heterostructures of semiconducting
transition metal dichalcogenides (TMDCs) amongst each other or with arbitrary
materials, through which the control of the chemical, structural, electronic,
spintronic, and optical properties can lead to a change in device paradigms. A
critical need is to understand the interface between TMDCs and insulating
substrates, for example high-$\kappa$ dielectrics, which can strongly impact
the electronic properties such as the optical gap. Here we show that the
chemical and electronic properties of the single-layer (SL) TMDC, WS$_2$, can
be transferred onto high-$\kappa$ transition metal oxide substrates TiO$_2$ and
SrTiO$_3$. The resulting samples are much more suitable for measuring their
electronic and chemical structures with angle-resolved photoemission than their
native-grown SiO$_2$ substrates. We probe the WS$_2$ on the micron scale across
100-micron flakes, and find that the occupied electronic structure is exactly
as predicted for freestanding SL WS$_2$ with a strong spin-orbit splitting of
420~meV and a direct band gap at the valence band maximum. Our results suggest
that TMDCs can be combined with arbitrary multi-functional oxides, which may
introduce alternative means of controlling the optoelectronic properties of
such materials.


title:
Mask-off: Synthesizing Face Images in the Presence of Head-mounted
  Displays

abstract:
  A head-mounted display (HMD) could be an important component of augmented
reality system. However, as the upper face region is seriously occluded by the
device, the user experience could be affected in applications such as
telecommunication and multi-player video games. In this paper, we first present
a novel experimental setup that consists of two near-infrared (NIR) cameras to
point to the eye regions and one visible-light RGB camera to capture the
visible face region. The main purpose of this paper is to synthesize realistic
face images without occlusions based on the images captured by these cameras.
To this end, we propose a novel synthesis framework that contains four modules:
3D head reconstruction, face alignment and tracking, face synthesis, and eye
synthesis. In face synthesis, we propose a novel algorithm that can robustly
align and track a personalized 3D head model given a face that is severely
occluded by the HMD. In eye synthesis, in order to generate accurate eye
movements and dynamic wrinkle variations around eye regions, we propose another
novel algorithm to colorize the NIR eye images and further remove the "red eye"
effects caused by the colorization. Results show that both hardware setup and
system framework are robust to synthesize realistic face images in video
sequences.


title:
Low-Delay Distributed Source Coding for Time-Varying Sources with
  Unknown Statistics

abstract:
  We consider a system in which two nodes take correlated measurements of a
random source with time-varying and unknown statistics. The observations of the
source at the first node are to be losslessly replicated with a given
probability of outage at the second node, which receives data from the first
node over a constant-rate errorless channel. We develop a system and associated
strategies for joint distributed source coding (encoding and decoding) and
transmission control in order to achieve low end-to-end delay. Slepian-Wolf
coding in its traditional form cannot be applied in our scenario, since the
encoder requires the joint statistics of the observations and the associated
decoding delay is very high. We analytically evaluate the performance of our
strategies and show that the delay achieved by them are order optimal, as the
conditional entropy of the source approaches to the channel rate. We also
evaluate the performance of our algorithms based on real-world experiments
using two cameras recording videos of a scene at different angles. Having
realized our schemes, we demonstrated that, even with a very low-complexity
quantizer, a compression ratio of approximately 50% is achievable for lossless
replication at the decoder, at an average delay of a few seconds.


title: Dynamical rigidity of non discrete representations in PSL(2,R)

abstract:
  The aim of this note is to advertise on a result, not stated explicitly, but
proved, in arXiv:0802.0512. Namely, if $\Gamma$ is any group, if $\rho_1$,
$\rho_2$ are representations of $\Gamma$ in $\mathrm{PSL}(2,\mathbb{R})$, one
of them being non elementary and non discrete, and if for all
$\gamma\in\Gamma$, $\rho_1(\gamma)$ and $\rho_2(\gamma)$ have the same rotation
number, then $\rho_1$ and $\rho_2$ are conjugate in
$\mathrm{PSL}(2,\mathbb{R})$. In particular, if two non discrete, non
elementary representations yield semi-conjugate actions on the circle, then
they are conjugate in $\mathrm{PSL}(2,\mathbb{R})$.


title: Science In the Cloud (SIC): A use case in MRI Connectomics

abstract:
  Modern technologies are enabling scientists to collect extraordinary amounts
of complex and sophisticated data across a huge range of scales like never
before. With this onslaught of data, we can allow the focal point to shift
towards answering the question of how we can analyze and understand the massive
amounts of data in front of us. Unfortunately, lack of standardized sharing
mechanisms and practices often make reproducing or extending scientific results
very difficult. With the creation of data organization structures and tools
which drastically improve code portability, we now have the opportunity to
design such a framework for communicating extensible scientific discoveries.
Our proposed solution leverages these existing technologies and standards, and
provides an accessible and extensible model for reproducible research, called
"science in the cloud" (sic). Exploiting scientific containers, cloud computing
and cloud data services, we show the capability to launch a computer in the
cloud and run a web service which enables intimate interaction with the tools
and data presented. We hope this model will inspire the community to produce
reproducible and, importantly, extensible results which will enable us to
collectively accelerate the rate at which scientific breakthroughs are
discovered, replicated, and extended.


title: Normal forms of endomorphism-valued power series

abstract:
  We show for $n,k\geq1$, and an $n$-dimensional complex vector space $V$ that
if an element $A\in\text{End}(V)[[z]]$ has constant term similar to a Jordan
block, then there exists a polynomial gauge transformation $g$ such that the
first $k$ coefficients of $gAg^{-1}$ have a controlled normal form.
Furthermore, we show that this normal form is unique by demonstrating explicit
relationships between the first $nk$ coefficients of the Puiseux series
expansion of the eigenvalues of $A$ and the entries of the first $k$
coefficients of $gAg^{-1}$.


title:
Intrinsic and extrinsic pinning in NdFeAs(O,F): vortex trapping and
  lock-in by the layered structure

abstract:
  The Fe-based superconductors (FBS) present a large variety of compounds whose
properties are affected to different extents by their crystal structures.
Amongst them, the $\it{RE}$FeAs(O,F) ($\it{RE}$1111, where $\it{RE}$ is a rare
earth element) is the family with the highest critical temperature $T_c$ but
also with a large anisotropy and Josephson vortices as demonstrated in the
flux-flow regime in Sm1111 ($T_c$ $\sim$ 55 K). Here we focus our attention on
the pinning properties of the lower-$T_c$ Nd1111 in the flux-creep regime. We
demonstrate that for H//c critical current density $J_c$ at high temperatures
is dominated by point-defect pinning centres, whereas at low temperatures
surface pinning by planar defects parallel to the $\it{c}$-axis and vortex
shearing prevail. When the field approaches the $\it{ab}$-planes, two different
regimes are observed at low temperatures as a consequence of the transition
between 3D-Abrikosov and 2D-Josephson vortices: one is determined by the
formation of a vortex staircase structure and one by lock-in of the vortices
parallel to the layers. This is the first study on FBS showing this behaviour
in a full temperature, field, and angular range and it demonstrates that,
despite the lower $T_c$ and anisotropy of Nd1111 with respect to Sm1111, this
compound is substantially affected by intrinsic pinning generating a strong
$\it{ab}$-peak in $J_c$.


title: A recursive formula for the motivic Milnor fiber of a plane curve

abstract:
  We find a recursive formula for the motivic Milnor fiber of an irreducible
plane curve, using the notions of a truncation and derived curve. We then apply
natural transformations to obtain a similar recursion for the Hodge-theoretic
spectrum.


title: Structural properties of dendrite groups

abstract:
  Let G be the homeomorphism group of a dendrite. We study the normal subgroups
of G. For instance, there are uncountably many non-isomorphic such groups G
that are simple groups. Moreover, these groups can be chosen so that any
isometric G-action on any metric space has a bounded orbit. In particular they
have the fixed point property (FH).


title:
S2DS: Physics-Based Compact Model for Circuit Simulation of
  Two-Dimensional Semiconductor Devices Including Non-Idealities

abstract:
  We present a physics-based compact model for two-dimensional (2D)
field-effect transistors (FETs) based on monolayer semiconductors such as MoS2.
A semi-classical transport approach is appropriate for the 2D channel, enabling
simplified analytical expressions for the drain current. In addition to
intrinsic FET behavior, the model includes contact resistance, traps and
impurities, quantum capacitance, fringing fields, high-field velocity
saturation and self-heating, the latter being found to play a strong role. The
model is calibrated with state-of-the-art experimental data for n- and p-type
2D-FETs, and it can be used to analyze device properties for sub-100 nm gate
lengths. Using the experimental fit, we demonstrate feasibility of circuit
simulations using properly scaled devices. The complete model is implemented in
SPICE-compatible Verilog-A, and a downloadable version is freely available on
the nanoHUB.org.


title:
Constraints on rapidity-dependent initial conditions from charged
  particle pseudorapidity densities and two-particle correlations

abstract:
  We study the initial three-dimensional spatial configuration of the
quark-gluon plasma produced in relativistic heavy-ion collisions using
centrality and rapidity-dependent measurements of charged particle
pseudorapidity densities and two-particle correlations. A cumulant-generating
function is used to parametrize the rapidity dependence of local entropy
deposition and extend arbitrary boost-invariant initial conditions to nonzero
beam rapidities. The model is compared to p+Pb and Pb+Pb single-particle
distributions and systematically optimized using Bayesian parameter estimation
to extract high-probability initial condition parameters. The optimized initial
conditions are then compared to a number of experimental observables including
two-particle rapidity correlations, the rapidity dependence of anisotropic
flow, and event-plane decorrelations.