title:
On the spatial distribution of neutral hydrogen in the Universe: bias
  and shot-noise of the HI Power Spectrum

abstract:
  The spatial distribution of neutral hydrogen (HI) in the Universe contains a
wealth of cosmological information. The 21 cm emission line can be used to map
the HI up to very high redshift and therefore reveal us something about the
evolution of the large scale structures in the Universe. However little is
known about the abundance and clustering properties of the HI over cosmic time.
Motivated by this, we build an analytic framework where the relevant parameters
that govern how the HI is distributed among dark matter halos can be fixed
using observations. At the same time we provide tools to study the column
density distribution function of the HI absorbers together with their
clustering properties. Our formalism is the first one able to account for all
observations at a single redshift, $z = 2.3$. The linear bias of the HI and the
mean number density of HI sources, two main ingredients in the calculation of
the signal-to-noise ratio of a cosmological survey, are then discussed in
detail, also extrapolating the results to low and high redshift. We find that
HI bias is relatively higher than the value reported in similar studies, but
the shot noise level is always sub dominant, making the HI Power Spectrum
always a high signal-to-noise measurements up to $z\simeq5$ in the limit of no
instrumental noise and foreground contamination.


title:
Real-Time Single Image and Video Super-Resolution Using an Efficient
  Sub-Pixel Convolutional Neural Network

abstract:
  Recently, several models based on deep neural networks have achieved great
success in terms of both reconstruction accuracy and computational performance
for single image super-resolution. In these methods, the low resolution (LR)
input image is upscaled to the high resolution (HR) space using a single
filter, commonly bicubic interpolation, before reconstruction. This means that
the super-resolution (SR) operation is performed in HR space. We demonstrate
that this is sub-optimal and adds computational complexity. In this paper, we
present the first convolutional neural network (CNN) capable of real-time SR of
1080p videos on a single K2 GPU. To achieve this, we propose a novel CNN
architecture where the feature maps are extracted in the LR space. In addition,
we introduce an efficient sub-pixel convolution layer which learns an array of
upscaling filters to upscale the final LR feature maps into the HR output. By
doing so, we effectively replace the handcrafted bicubic filter in the SR
pipeline with more complex upscaling filters specifically trained for each
feature map, whilst also reducing the computational complexity of the overall
SR operation. We evaluate the proposed approach using images and videos from
publicly available datasets and show that it performs significantly better
(+0.15dB on Images and +0.39dB on Videos) and is an order of magnitude faster
than previous CNN-based methods.


title:
Density distribution of a dust cloud in three-dimensional complex
  plasmas

abstract:
  We propose a novel method of determination of the dust particle spatial
distribution in dust clouds that form in three-dimensional (3D) complex plasmas
under microgravity conditions. The method utilizes the data obtained during the
3D scanning of a cloud and provides a reasonably good accuracy. Based on this
method, we investigate the particle density in a dust cloud realized in gas
discharge plasma in the PK-3 Plus setup onboard the International Space
Station. We find that the treated dust clouds are both anisotropic and
inhomogeneous. One can isolate two regimes, in which a stationary dust cloud
can be observed. At low pressures, the particle density decreases monotonically
with the increase of the distance from the discharge center; at higher
pressures, the density distribution has a shallow minimum. Regardless of the
regime, we detect a cusp of the distribution at the void boundary and a slowly
varying density at larger distances (in the foot region). A theoretical
interpretation of obtained results is developed that leads to reasonable
estimates of the densities for both the cusp and foot. The modified ionization
equation of state, which allows for violation of the local quasineutrality in
the cusp region, predicts the spatial distributions of ion and electron
densities to be measured in future experiments.


title:
Energy-Efficient Resource Allocation for SWIPT in Multiple Access
  Channels

abstract:
  In this paper, we study optimal resource allocation strategies for
simultaneous information and power transfer (SWIPT) focusing on the system
energy efficiency. We consider two-user multiple access channels in which
energy harvesting (EH) and information decoding (ID) nodes are spatially
separated. We formulate optimization problems that maximize system energy
efficiency while taking harvested energy constraints into account. These are
concave-linear fractional problems, and hence Karush-Kuhn-Tucker (KKT)
conditions are necessary and sufficient to obtain globally optimal solution.
Solving these optimization problems, we provide analytical expressions for
optimal transmit power allocation among the source nodes, and identify the
corresponding energy efficiency. We confirm the theoretical analysis via
numerical results. Furthermore, we also characterize the effect of circuit
power consumption on the system's efficiency as the harvested energy demand
varies.


title: Rational Whitney tower filtration of links

abstract:
  We present complete classifications of links in the 3-sphere modulo framed
and twisted Whitney towers in a rational homology 4-ball. This provides a
geometric characterization of the vanishing of the Milnor invariants of links
in terms of Whitney towers. Our result also says that the higher order Arf
invariants, which are conjectured to be nontrivial, measure the potential
difference between the Whitney tower theory in rational homology 4-balls and
that in the 4-ball extensively developed by Conant, Schneiderman and Teichner.


title: No-Regret Replanning under Uncertainty

abstract:
  This paper explores the problem of path planning under uncertainty.
Specifically, we consider online receding horizon based planners that need to
operate in a latent environment where the latent information can be modeled via
Gaussian Processes. Online path planning in latent environments is challenging
since the robot needs to explore the environment to get a more accurate model
of latent information for better planning later and also achieves the task as
quick as possible. We propose UCB style algorithms that are popular in the
bandit settings and show how those analyses can be adapted to the online
robotic path planning problems. The proposed algorithm trades-off exploration
and exploitation in near-optimal manner and has appealing no-regret properties.
We demonstrate the efficacy of the framework on the application of aircraft
flight path planning when the winds are partially observed.


title: Quantum Thermal Rectification to design thermal diodes and transistors

abstract:
  We study in this article how heat can be exchanged between two level systems
(TLS) each of them being coupled to a thermal reservoir. Calculation are
performed solving a master equation for the density matrix using the Born
markov-approximation. We analyse the conditions for which a thermal diode and a
thermal transistor can be obtained as well as their optimization.


title:
Dispersive estimates for Dirac Operators in dimension three with
  obstructions at threshold energies

abstract:
  We investigate $L^1\to L^\infty$ dispersive estimates for the three
dimensional Dirac equation with a potential. We also classify the structure of
obstructions at the thresholds of the essential spectrum as being composed of a
two dimensional space of resonances and finitely many eigenfunctions. We show
that, as in the case of the Schr\"odinger evolution, the presence of a
threshold obstruction generically leads to a loss of the natural $t^{-\frac32}$
decay rate. In this case we show that the solution operator is composed of a
finite rank operator that decays at the rate $t^{-\frac12}$ plus a term that
decays at the rate $t^{-\frac32}$.


title:
ADC Bit Allocation under a Power Constraint for MmWave Massive MIMO
  Communication Receivers

abstract:
  Millimeter wave (mmWave) systems operating over a wide bandwidth and using a
large number of antennas impose a heavy burden on power consumption. In a
massive multiple-input multiple-output (MIMO) uplink, analog-to-digital con-
verters (ADCs) would be the primary consumer of power in the base station
receiver. This paper proposes a bit allocation (BA) method for mmWave
multi-user (MU) massive MIMO systems under a power constraint. We apply ADCs to
the outputs of an analog phased array for beamspace projection to exploit
mmWave channel sparsity. We relax a mean square quantization error (MSQE)
minimization problem and map the closed-form solution to non-negative integer
bits at each ADC. In link-level simulations, the proposed method gives better
communication performance than conventional low-resolution ADCs for the same or
less power. Our contribution is a near optimal low-complexity BA method that
minimizes total MSQE under a power constraint.


title: On fixed gain recursive estimators with discontinuity in the parameters

abstract:
  In this paper we estimate the tracking error of a fixed gain stochastic
approximation scheme. The underlying process is not assumed Markovian, a mixing
condition is required instead. Furthermore, the updating function may be
discontinuous in the parameter.


title:
Improving the semidefinite programming bound for the kissing number by
  exploiting polynomial symmetry

abstract:
  The kissing number of $\mathbb{R}^n$ is the maximum number of
pairwise-nonoverlapping unit spheres that can simultaneously touch a central
unit sphere. Mittelmann and Vallentin (2010), based on the semidefinite
programming bound of Bachoc and Vallentin (2008), computed the best known upper
bounds for the kissing number for several values of $n \leq 23$. In this paper,
we exploit the symmetry present in the semidefinite programming bound to
provide improved upper bounds for $n = 9, \ldots, 23$.


title: Lasing Action with Gold Nanorod Hyperbolic Metamaterials

abstract:
  Coherent nanoscale photon sources are of paramount importance to achieving
all-optical communication. Several nanolasers smaller than the diffraction
limit have been theoretically proposed and experimentally demonstrated using
plasmonic cavities to confine optical fields. Such compact cavities exhibit
large Purcell factors, thereby enhancing spontaneous emission, which feeds into
the lasing mode. However, most plasmonic nanolasers reported so far have
employed resonant nanostructures and therefore had the lasing restricted to the
proximity of the resonance wavelength. Here, we report on an approach based on
gold nanorod hyperbolic metamaterials for lasing. Hyperbolic metamaterials
provide broadband Purcell enhancement due to large photonic density of optical
states, while also supporting surface plasmon modes to deliver optical feedback
for lasing due to nonlocal effects in nanorod media. We experimentally
demonstrate the advantage of hyperbolic metamaterials in achieving lasing
action by its comparison with that obtained in a metamaterial with elliptic
dispersion. The conclusions from the experimental results are supported with
numerical simulations comparing the Purcell factors and surface plasmon modes
for the metamaterials with different dispersions. We show that although the
metamaterials of both types support lasing, emission with hyperbolic samples is
about twice as strong with 35% lower threshold vs. the elliptic ones. Hence,
hyperbolic metamaterials can serve as a convenient platform of choice for
nanoscale coherent photon sources in a broad wavelength range.


title: An integral Relationship for a new Fractional One-phase Stefan Problem

abstract:
  A one-dimensional fractional one-phase Stefan problem with a temperature
boundary condition at the fixed face is considered. An integral relationship
between the temperature and the free boundary is obtained which is equivalent
to the fractional Stefan condition. Moreover, an exact solution of similarity
type expressed in terms of Wright functions is given.


title: Should Terminology Principles be re-examined?

abstract:
  Operationalization of terminology for IT applications has revived the
Wusterian approach. The conceptual dimension once more prevails after taking
back seat to specialised lexicography. This is demonstrated by the emergence of
ontology in terminology. While the Terminology Principles as defined in Felber
manual and the ISO standards remain at the core of traditional terminology,
their computational implementation raises some issues. In this article, while
reiterating their importance, we will be re-examining these Principles from a
dual perspective: that of logic in the mathematical sense of the term and that
of epistemology as in the theory of knowledge. We will thus be clarifying and
describing some of them so as to take into account advances in knowledge
engineering (ontology) and formal systems (logic). The notion of
ontoterminology, terminology whose conceptual system is a formal ontology,
results from this approach.


title:
Cumulants and nonlinear response of high $p_T$ harmonic flow at
  $\sqrt{s_{NN}}=5.02$ TeV

abstract:
  Event-by-event fluctuations caused by quantum mechanical fluctuations in the
wave function of colliding nuclei in ultrarelativistic heavy ion collisions
were recently shown to be necessary for the simultaneous description of
$R_{AA}$ as well as the elliptic and triangular flow harmonics at high $p_T$ in
PbPb collisions at the Large Hadron Collider. In fact, the presence of a finite
triangular flow as well as cumulants of the flow harmonic distribution that
differ from the mean are only possible when these event-by-event fluctuations
are considered. In this paper we combine event-by-event viscous hydrodynamics
and jet quenching to make predictions for high $p_T$ $R_{AA}$, $v_2\{2\}$,
$v_3\{2\}$, and $v_2\{4\}$ in PbPb collisions at $\sqrt{s_{NN}}=5.02$ TeV. With
an order of magnitude larger statistics we find that high $p_T$ elliptic flow
does not scale linearly with the soft elliptical flow, as originally thought,
but has deviations from perfectly linear scaling. A new experimental
observable, which involves the difference between the ratio of harmonic flow
cumulants at high and low $p_T$, is proposed to investigate the fluctuations of
high $p_T$ flow harmonics and measure this nonlinear response. By varying the
path length dependence of the energy loss and the viscosity of the evolving
medium we find that $R_{AA}(p_T)$ and $v_2\{2\}(p_T)$ strongly depend on the
choice for the path length dependence of the energy loss, which can be
constrained using the new LHC run 2 data.


title:
Long term stability and reproducibility of magnetic colloids are key
  issues for steady values of Specific Power Absorption through time

abstract:
  Virtually all clinical applications of magnetic nanoparticles (MNPs) require
the formulation of biocompatible, water-based magnetic colloids. For magnetic
hyperthermia, the requirements also include a high colloidal stability against
precipitation and agglomeration of the constituent MNPs, in order to keep the
heating efficiency of the ferrofluid in the long term. The specific power
absorption (SPA) of single-domain MNPs depends critically on the average
particle size and size distribution width, therefore first-rate reproducibility
among different batches regarding these parameters are also needed. We have
studied the evolution of the SPA of highly reproducible and stable water-based
colloid composed of polymer coated $Fe_{3}O_{4}$ magnetic nanoparticles. By
measuring the specific power absorption (SPA) values along one year as a
function of field amplitude and frequencies ($H \leq 24 kA/m$; $260 \leq f \leq
830 kHz$), we demonstrated that SPA in these samples can be made reproducible
between successive synthesis, and stable along several months, due to the in
situ polymer coating that provides colloidal stability and keeps dipolar
interactions negligible.


title:
Simulating device-to-device communications in OMNeT++ with SimuLTE:
  scenarios and configurations

abstract:
  SimuLTE is a tool that enables system-level simulations of LTE/LTE-Advanced
networks within OMNeT++. It is designed such that it can be plugged within
network elements as an additional Network Interface Card (NIC) to those already
provided by the INET framework (e.g. Wi-Fi). Recently, device-to-device (D2D)
technology has been widely studied by the research community, as a mechanism to
allow direct communications between devices of a LTE cellular network. In this
work, we present how SimuLTE can be employed to simulate both one-to-one and
one-to-many D2D communications, so that the latter can be exploited as a new
communication opportunity in several research fields, like vehicular networks,
IoT and machine-to-machine (M2M) applications.


title:
On groups, slow heat kernel decay yields Liouville property and sharp
  entropy bounds

abstract:
  Let $\mu$ be a symmetric probability measure of finite entropy on a group
$G$. We show that if $-\log \mu^{(2n)}(id)=o(n^{1/2})$, then the pair $(G,\mu)$
has the Liouville property (all bounded $\mu$-harmonic functions on $G$ are
constant). Furthermore, if $-\log \mu^{(2n)}(id)=O(n^{\beta})$ where
$\beta\in(0,1/2)$, then the entropy of the $n$-fold convolution power
$\mu^{(n)}$ satisfies $H(\mu^{(n)})=O\left(n^{\frac{\beta}{1-\beta}}\right)$.
This improves earlier results of Gournay and of Saloff-Coste and the second
author. We extend the bounds to transitive graphs and illustrate their
sharpness on a family of groups.


title:
A test of Gaia Data Release 1 parallaxes: implications for the local
  distance scale

abstract:
  We present a comparison of Gaia Data Release 1 (DR1) parallaxes with
photometric parallaxes for a sample of 212 Galactic Cepheids at a median
distance of 2~kpc, and explore their implications on the distance scale and the
local value of the Hubble constant H_0. The Cepheid distances are estimated
from a recent calibration of the near-infrared Period-Luminosity P-L relation.
The comparison is carried out in parallax space, where the DR1 parallax errors,
with a median value of half the median parallax, are expected to be
well-behaved. With the exception of one outlier, the DR1 parallaxes are in
remarkably good global agreement with the predictions, and the published errors
may be conservatively overestimated by about 20%. The parallaxes of 9 Cepheids
brighter than G = 6 may be systematically underestimated, trigonometric
parallaxes measured with the HST FGS for three of these objects confirm this
trend. If interpreted as an independent calibration of the Cepheid luminosities
and assumed to be otherwise free of systematic uncertainties, DR1 parallaxes
would imply a decrease of 0.3% in the current estimate of the local Hubble
constant, well within their statistical uncertainty, and corresponding to a
value 2.5 sigma (3.5 sigma if the errors are scaled) higher than the value
inferred from Planck CMB data used in conjunction with Lambda-CDM. We also test
for a zeropoint error in Gaia parallaxes and find none to a precision of ~20
muas. We caution however that with this early release, the complete systematic
properties of the measurements may not be fully understood at the statistical
level of the Cepheid sample mean, a level an order of magnitude below the
individual uncertainties. The early results from DR1 demonstrate again the
enormous impact that the full mission will likely have on fundamental questions
in astrophysics and cosmology.


title: Components of affine Springer fibers

abstract:
  Let $\mathbf{G}$ be a connected split reductive group over a field of
characteristic zero or sufficiently large characteristic,
$\gamma_0\in(\operatorname{Lie}\mathbf{G})((t))$ be any topologically nilpotent
regular semisimple element, and $\gamma=t\gamma_0$. Using methods from $p$-adic
orbital integrals, we show that the number of components of the Iwahori affine
Springer fiber over $\gamma$ modulo $Z_{\mathbf{G}((t))}(\gamma)$ is equal to
the order of the Weyl group.


title: The microstructural foundations of leverage effect and rough volatility

abstract:
  We show that typical behaviors of market participants at the high frequency
scale generate leverage effect and rough volatility. To do so, we build a
simple microscopic model for the price of an asset based on Hawkes processes.
We encode in this model some of the main features of market microstructure in
the context of high frequency trading: high degree of endogeneity of market,
no-arbitrage property, buying/selling asymmetry and presence of metaorders. We
prove that when the first three of these stylized facts are considered within
the framework of our microscopic model, it behaves in the long run as a Heston
stochastic volatility model, where leverage effect is generated. Adding the
last property enables us to obtain a rough Heston model in the limit,
exhibiting both leverage effect and rough volatility. Hence we show that at
least part of the foundations of leverage effect and rough volatility can be
found in the microstructure of the asset.


title:
Privacy Preserving Distance Computation using Somewhat-trusted Third
  Parties

abstract:
  A critically important component of most signal processing procedures is that
of computing the distance between signals. In multi-party processing
applications where these signals belong to different parties, this introduces
privacy challenges. The signals may themselves be private, and the parties to
the computation may not be willing to expose them. Solutions proposed to the
problem in the literature generally invoke homomorphic encryption schemes,
secure multi-party computation, or other cryptographic methods which introduce
significant computational complexity into the proceedings, often to the point
of making more complex computations requiring repeated computations unfeasible.
Other solutions invoke third parties, making unrealistic assumptions about
their trustworthiness.
  In this paper we propose an alternate approach, also based on third party
computation, but without assuming as much trust in the third party. Individual
participants to the computation "secure" their data through a proposed secure
hashing scheme with shared keys, prior to sharing it with the third party. The
hashing ensures that the third party cannot recover any information about the
individual signals or their statistics, either from analysis of individual
computations or their long-term aggregate patterns. We provide theoretical
proof of these properties and empirical demonstration of the feasibility of the
computation.


title:
Extending OMNeT++ Towards a Platform for the Design of Future In-Vehicle
  Network Architectures

abstract:
  In-vehicle communication technologies are evolving. While today's cars are
equipped with fieldbusses to interconnect the various electronic control units,
next generation vehicles have timing and bandwidth requirements that exceed the
capacities. In particular Advanced Driver Assistance Systems (ADAS) and
automated driving using high bandwidth sensors such as cameras, LIDAR or radar
will challenge the in-car network. Automotive Ethernet is the most promising
candidate to solve the upcoming challenges. But to design and evaluate new
protocols, concepts, and architectures suitable analysis tools are required.
Especially in the interim period with architectures using automotive Ethernet
and legacy fieldbusses together, careful planning and design is of vital
importance. Simulation can provide a good understanding of the expectable
network metrics in an early development phase. This paper contributes a
workflow as well as the required toolchain to evaluate new real-time Ethernet
communication architectures using event based simulation in OMNeT++. We
introduce a domain specific language (DSL) - the Abstract Network Description
Language (ANDL) - to describe and configure the simulation and present the
required simulation models for real-time Ethernet and fieldbus technologies
such as CAN and FlexRay. We further introduce new analysis tools for special
in-vehicle network use-cases and the interaction of the simulation with
third-party applications established in the automotive domain.


title:
Grammatical Templates: Improving Text Difficulty Evaluation for Language
  Learners

abstract:
  Language students are most engaged while reading texts at an appropriate
difficulty level. However, existing methods of evaluating text difficulty focus
mainly on vocabulary and do not prioritize grammatical features, hence they do
not work well for language learners with limited knowledge of grammar. In this
paper, we introduce grammatical templates, the expert-identified units of
grammar that students learn from class, as an important feature of text
difficulty evaluation. Experimental classification results show that
grammatical template features significantly improve text difficulty prediction
accuracy over baseline readability features by 7.4%. Moreover, we build a
simple and human-understandable text difficulty evaluation approach with 87.7%
accuracy, using only 5 grammatical template features.


title: Information Theoretic Limits of Data Shuffling for Distributed Learning

abstract:
  Data shuffling is one of the fundamental building blocks for distributed
learning algorithms, that increases the statistical gain for each step of the
learning process. In each iteration, different shuffled data points are
assigned by a central node to a distributed set of workers to perform local
computations, which leads to communication bottlenecks. The focus of this paper
is on formalizing and understanding the fundamental information-theoretic
trade-off between storage (per worker) and the worst-case communication
overhead for the data shuffling problem. We completely characterize the
information theoretic trade-off for $K=2$, and $K=3$ workers, for any value of
storage capacity, and show that increasing the storage across workers can
reduce the communication overhead by leveraging coding. We propose a novel and
systematic data delivery and storage update strategy for each data shuffle
iteration, which preserves the structural properties of the storage across the
workers, and aids in minimizing the communication overhead in subsequent data
shuffling iterations.


title: Emission of Photons and Relativistic Axions from Axion Stars

abstract:
  The number of nonrelativistic axions can be changed by inelastic reactions
that produce photons or relativistic axions. Any odd number of axions can
annihilate into two photons. Any even number of nonrelativistic axions can
scatter into two relativistic axions. We calculate the rate at which axions are
lost from axion stars from these inelastic reactions. In dilute systems of
axions, the dominant inelastic reaction is axion decay into two photons. In
sufficiently dense systems of axions, the dominant inelastic reaction is the
scattering of four nonrelativistic axions into two relativistic axions. The
scattering of odd numbers of axions into two photons produces monochromatic
radio-frequency signals at odd-integer harmonics of the fundamental frequency
set by the axion mass. This provides a unique signature for dense systems of
axions, such as a dense axion star or a collapsing dilute axion star.


title:
Relativistic Aberration and the Cosmological Constant in Gravitational
  Lensing I: Introduction

abstract:
  An analysis of null geodesics in Schwarzschild de Sitter space is presented
with special attention to their global `bending angles', local measurable
angles, and the involvement of the cosmological constant. We make use of a
general technique which allows for finding observable intersection angles of
null trajectories analytically. A general relativistic aberration relationship
is established as one of its applications. The question of whether or not the
cosmological constant, $\Lambda$, contributes to orbits of light and to related
observable quantities is addressed in detail. We also discuss the ongoing
debate on this issue and respond to some recent papers on the topic. The
dependence of measurable quantities on the motion of observers is stressed
throughout. Exact formulas for measurable intersection angles, as well as
gravitational lens equations for observers in the Schwarzschild de Sitter
background are provided.


title:
Estimation of Sobolev embedding constant on a domain dividable into
  bounded convex domains

abstract:
  This paper is concerned with an explicit value of the embedding constant from
$W^{1,q}(\Omega)$ to $L^{p}(\Omega)$ for a bounded domain
$\Omega\subset\mathbb{R}^N~(N\in\mathbb{N})$, where $1\leq q\leq p\leq \infty$.
To obtain this value, we previously proposed a formula for estimating the
embedding constant on bounded and unbounded Lipschitz domains by estimating the
norm of Stein's extension operator, in the article (K. Tanaka, K. Sekine, M.
Mizuguchi, and S. Oishi, Estimation of Sobolev-type embedding constant on
domains with minimally smooth boundary using extension operator, Journal of
Inequalities and Applications, Vol. 389, pp. 1-23, 2015). This formula is also
applicable to a domain that can be divided into Lipschitz domains. However, the
values computed by the previous formula are very large. In this paper, we
propose several sharper estimations of the embedding constant on a bounded
domain that can be divided into convex domains.


title:
The wild monodromy of the Fifth Painlev\'e equation and its action on
  wild character variety: an approach of confluence

abstract:
  The article studies the Fifth Painlev\'e equation and of the nonlinear Stokes
phenomenon at its irregular singularity at infinity from the point of view of
confluence from the Sixth Painlev\'e equation. This approach is developped
separately on both sides of the Riemann-Hilbert correspondance. On the side of
the nonlinear Painlev\'e-Okamoto foliation the relation between the nonlinear
monodromy group of Painlev\'e VI and the "nonlinear wild monodromy pseudogroup"
of Painlev\'e V (that is the pseudogroup generated by nonlinear monodromy,
nonlinear Stokes operators and nonlinear exponential torus) is explained in
detail. On the side of the corresponding linear isomonodromic problem, the
"wild" character variety (the space of the linear monodromy and Stokes data)
associated to Painlev\'e V is constructed through a birational transformation
from the character variety (the space of the linear monodromy data) associated
to Painlev\'e VI. This allows to transport the known description of the action
of the nonlinear monodromy of Painlev\'e VI on its character variety to that of
Painlev\'e V, and to provide explicit formulas for the action of the "nonlinear
wild monodromy" of Painlev\'e V on its character variety.


title: Spatial Multiresolution Analysis of the Effect of PM2.5 on Birth Weights

abstract:
  Fine particulate matter (PM2.5) measured at a given location is a mix of
pollution generated locally and pollution traveling long distances in the
atmosphere. Therefore, the identification of spatial scales associated with
health effects can inform on pollution sources responsible for these effects,
resulting in more targeted regulatory policy. Recently, prediction methods that
yield high-resolution spatial estimates of PM2.5 exposures allow one to
evaluate such scale-specific associations. We propose a two-dimensional wavelet
decomposition that alleviates restrictive assumptions required for standard
wavelet decompositions. Using this method we decompose daily surfaces of PM2.5
to identify which scales of pollution are most associated with adverse health
outcomes. A key feature of the approach is that it can remove the purely
temporal component of variability in PM2.5 levels and calculate effect
estimates derived solely from spatial contrasts. This eliminates the potential
for unmeasured confounding of the exposure - outcome associations by temporal
factors, such as season. We apply our method to a study of birth weights in
Massachusetts, U.S.A from 2003-2008 and find that both local and urban sources
of pollution are strongly negatively associated with birth weight. Results also
suggest that failure to eliminate temporal confounding in previous analyses
attenuated the overall effect estimate towards zero, with the effect estimate
growing in magnitude once this source of variability is removed.


title:
Optimizing isotope and vacancy engineering in graphene ribbons to
  enhance the thermoelectric performance without degrading the electronic
  properties

abstract:
  The enhancement of thermoelectric figure of merit ZT requires to either
increase the power factor or reduce the phonon conductance, or even both. In
graphene, the high phonon thermal conductivity is the main factor limiting the
thermoelectric conversion. The common strategy to enhance ZT is therefore to
introduce phonon scatterers to suppress the phonon conductance while retaining
high electrical conductance and Seebeck coefficient. Although thermoelectric
performance is eventually enhanced, all studies based on this strategy show a
significant reduction of the electrical conductance, most often leading to a
lower electronic performance. In this study we show that appropriate sources of
disorder, including isotopes and vacancies at lowest electron density
positions, can be used as phonon scatterers to reduce the phonon conductance in
graphene ribbons without degrading the electrical conductance, particularly in
the low-energy region which is the most important range for device operation.
By means of atomistic calculations using semi-empirical Tight-Binding and Force
Constant models in combination with Non-Equilibrium Green function formalism,
we show that the natural electronic properties of graphene ribbons can be fully
preserved while their thermoelectric efficiency is strongly enhanced. For
ribbons of width M = 5 dimer lines, room-temperature ZT is enhanced from less
than 0.26 for defect-free ribbons to more than 2.5. This study is likely to set
the milestones of a new generation of nano-devices with dual electronic,
thermoelectric functionalities.


title: Mode testing, critical bandwidth and excess mass

abstract:
  The identification of peaks or maxima in probability densities, by mode
testing or bump hunting, has become an important problem in applied fields.
This task has been approached in the statistical literature from different
perspectives, with the proposal of testing procedures which are based on kernel
density estimators or on the quantification of excess mass. However, none of
the existing proposals provides a satisfactory performance in practice. In this
work, a new procedure which combines the previous approaches (smoothing and
excess mass) is presented and compared with the existing methods, showing a
superior behaviour. A real data example on philatelic data is also included for
illustration purposes.


title: Higher order selfdual toric varieties

abstract:
  The notion of higher order dual varieties of a projective variety, introduced
in \cite{P83}, is a natural generalization of the classical notion of
projective duality. In this paper we present geometric and combinatorial
characterizations of those equivariant projective toric embeddings that satisfy
higher order selfduality. We also give several examples and general
constructions. In particular, we highlight the relation with Cayley-Bacharach
questions and with Cayley configurations.


title: Theory News Higgs

abstract:
  I review new developments in Higgs physics, with a focus on Yukawa couplings
in and beyond the standard model. In particular, I discuss different methods of
measuring the light Yukawas, new sources of CP violation in the Higgs sector,
and lepton flavor violation.


title: Gradient Descent Learns Linear Dynamical Systems

abstract:
  We prove that stochastic gradient descent efficiently converges to the global
optimizer of the maximum likelihood objective of an unknown linear
time-invariant dynamical system from a sequence of noisy observations generated
by the system. Even though the objective function is non-convex, we provide
polynomial running time and sample complexity bounds under strong but natural
assumptions. Linear systems identification has been studied for many decades,
yet, to the best of our knowledge, these are the first polynomial guarantees
for the problem we consider.


title:
Extended X-ray Monitoring of Gravitational Lenses with Chandra and Joint
  Constraints on X-ray Emission Regions

abstract:
  We present an X-ray photometric analysis of six gravitationally lensed
quasars, with observation campaigns spanning from 5 to 14 years, measuring the
total (0.83 - 21.8 keV restframe), soft (0.83 - 3.6 keV), and hard (3.6 - 21.8
keV) band image flux ratios or each epoch. Using the ratios of the
model-predicted macro-magnifications as baselines, we build differential
microlensing light curves and obtain joint likelihood functions for the average
X-ray emission region sizes. Our analysis yields a Probability Distribution
Function for the average half-light radius of the X-Ray emission region in the
sample that peaks slightly above 1 gravitational radius and with nearly
indistinguishable 68% confidence (one-sided) upper limits of 17.8 and 18.9
gravitational radii for the soft and hard X-ray emitting regions, assuming a
mean stellar mass of 0.3 solar masses. We see hints of energy dependent
microlensing between the soft and hard bands in two of the objects. In a
separate analysis on the root-mean-square of the microlensing variability, we
find significant differences between the soft and hard bands but the sign of
the difference is not consistent across the sample. This suggests the existence
of some kind of spatial structure to the X-ray emission in an otherwise
extremely compact source. We also discover a correlation between the RMS
microlensing variability and the average microlensing amplitude.


title: Casimir Force Phase Transitions in the Graphene Family

abstract:
  The Casimir force is a universal interaction induced by electromagnetic
quantum fluctuations between any types of objects. The expansion of the
graphene family by adding silicene, germanene, and stanene, 2D allotropes of
Si, Ge, and Sn, lands itself as a platform to probe Dirac-like physics in
honeycomb staggered systems in such a ubiquitous interaction. We discover
Casimir force phase transitions between these staggered 2D materials induced by
the complex interplay between Dirac physics, spin-orbit coupling, and
externally applied fields. In particular, we find that the interaction energy
experiences different power law distance decays, magnitudes, and dependences on
characteristic physical constants. Furthermore, due to the topological
properties of these materials, repulsive and quantized Casimir interactions
become possible.


title: The Bradley--Terry condition is $L_1$--testable

abstract:
  We provide an algorithm with constant running time that given a weighted
tournament $T$, distinguishes with high probability of success between the
cases that $T$ can be represented by a Bradley--Terry model, or cannot even be
approximated by one. The same algorithm tests whether the corresponding Markov
chain is reversible.


title: Mathematical Properties of Numerical Inversion for Jet Calibrations

abstract:
  Numerical inversion is a general detector calibration technique that is
independent of the underlying spectrum. This procedure is formalized and
important statistical properties are presented, using high energy jets at the
Large Hadron Collider as an example setting. In particular, numerical inversion
is inherently biased and common approximations to the calibrated jet energy
tend to over-estimate the resolution. Analytic approximations to the closure
and calibrated resolutions are demonstrated to effectively predict the full
forms under realistic conditions. Finally, extensions of numerical inversion
are presented which can reduce the inherent biases. These methods will be
increasingly important to consider with degraded resolution at low jet energies
due to a much higher instantaneous luminosity in the near future.


abstract:
  We study Jordan-Lie inner ideals of finite dimensional associative algebras
and the corresponding Lie algebras and prove that they admit Levi
decompositions. Moreover, we classify Jordan-Lie inner ideals satisfying a
certain minimality condition and show that they are generated by pairs of
idempotents.


title: Parametric Resonance in the Early Universe - A Fitting Analysis

abstract:
  Particle production via parametric resonance in the early Universe, is a
nonperturbative, non-linear and out-of-equilibrium phenomenon. Although it is a
well studied topic, whenever a new scenario exhibits parametric resonance, a
full re-analysis is normally required. To avoid this tedious task, many works
present often only a simplified linear treatment of the problem. In order to
surpass this circumstance in the future, we provide a fitting analysis of
parametric resonance through all its relevant stages: initial linear growth,
non-linear evolution, and relaxation towards equilibrium. Using lattice
simulations in an expanding grid in 3 + 1 dimensions, we parametrize the
dynamics outcome scanning over the relevant ingredients: role of the
oscillatory field, particle coupling strength, initial conditions, and
background expansion rate. We emphasize the inaccuracy of the linear
calculation of the decay time of the oscillatory field, and propose a more
appropriate definition of this scale based on the subsequent non-linear
dynamics. We provide simple fits to the relevant time scales and particle
energy fractions at each stage. Our fits can be applied to post-inflationary
preheating scenarios, where the oscillatory field is the inflaton, or to
spectator-field scenarios, where the oscillatory field can be e.g. a curvaton,
or the Standard Model Higgs.


title:
Stacked-VLAN-Based Modeling of Hybrid ISP Traffic Control Schemes and
  Service Plans Exploiting Excess Bandwidth in Shared Access Networks

abstract:
  The current practice of shaping subscriber traffic using a token bucket
filter by Internet service providers may result in a severe waste of network
resources in shared access networks; except for a short period of time
proportional to the size of a token bucket, it cannot allocate excess bandwidth
among active subscribers even when there are only a few active subscribers. To
better utilize the network resources in shared access networks, therefore, we
recently proposed and analyzed the performance of access traffic control
schemes, which can allocate excess bandwidth among active subscribers
proportional to their token generation rates. Also, to exploit the excess
bandwidth allocation enabled by the proposed traffic control schemes, we have
been studying flexible yet practical service plans under a hybrid traffic
control architecture, which are attractive to both an Internet service provider
and its subscribers in terms of revenue and quality of service. In this paper
we report the current status of our modeling of the hybrid traffic control
schemes and service plans with OMNeT++/INET-HNRL based on IEEE standard 802.1Q
stacked VLANs.


title: Implementation of the SWIM Mobility Model in OMNeT++

abstract:
  The Internet of Things (IoT) is expected to grow into billions of devices in
the near future. Evaluating mechanisms such as networking architectures for
communications in the IoT require the use of simulators due to the scale of the
size of networks. Mobility is one of the key aspects that need to be evaluated
when considering the different scenarios of the IoT. Small Worlds in Motion
(SWIM) is a mobility model that mathematically characterises the movement
patterns of humans. The work presented in this paper details the development
and verification of the SWIM mobility model in the OMNeT++ simulator.


title: Chinese Medical Device Market and The Investment Vector

abstract:
  China has attracted increasing amounts of foreign investment since it opened
its doors to the world and whilst many analysts have focused on foreign
investment in popular areas, little has been written about medical device
investment. The purpose of this article is to analyze the status of the Chinese
medical device market from the perspective of the healthcare industry and its
important market drivers; the study reveals that the medical device market has
significant growth potential. This article aims to identify and assess the
profitable sectors of medical device technologies as a guide for international
companies and investors.


title:
Neutrino emissivities and bulk viscosity in neutral two-flavor quark
  matter

abstract:
  We study thermodynamic and transport properties for the isotropic
color-spin-locking (iso-CSL) phase of two-flavor superconducting quark matter
under compact star constraints within a NJL-type chiral quark model. Chiral
symmetry breaking and the phase transition to superconducting quark matter
leads to a density dependent change of quark masses, chemical potentials and
diquark gap. A self-consistent treatment of these physical quantities
influences on the microscopic calculations of transport properties. We present
results for the iso-CSL direct URCA emissivities and bulk viscosities, which
fulfill the constraints on quark matter derived from cooling and rotational
evolution of compact stars. We compare our results with the phenomenologically
successful, but yet heuristic 2SC+X phase. We show that the microscopically
founded iso-CSL phase can replace the purely phenomenological 2SC+X phase in
modern simulations of the cooling evolution for compact stars with color
superconducting quark matter interior.


title:
A versatile framework for simulating the dynamic mechanical structure of
  cytoskeletal networks

abstract:
  Computer simulations can aid in understanding how collective materials
properties emerge from interactions between simple constituents. Here, we
introduce a coarse-grained model that enables simulation of networks of actin
filaments, myosin motors, and crosslinking proteins at biologically relevant
time and length scales. We demonstrate that the model qualitatively and
quantitatively captures a suite of trends observed experimentally, including
the statistics of filament fluctuations, mechanical responses to shear, motor
motilities, and network rearrangements. We use the simulation to predict the
viscoelastic scaling behavior of crosslinked actin networks, characterize the
trajectories of actin in a myosin motility assay, and develop order parameters
to measure contractility of a simulated actin network. The model can thus serve
as a platform for interpretation and design of cytoskeletal materials
experiments, as well as for further development of simulations incorporating
active elements.


title: The spectrum of diagonal perturbation of weighted shift operator

abstract:
  This paper provides a description of the spectrum of diagonal perturbation of
weighted shift operator acting on a separable Hilbert space.


title: Scaling up Echo-State Networks with multiple light scattering

abstract:
  Echo-State Networks and Reservoir Computing have been studied for more than a
decade. They provide a simpler yet powerful alternative to Recurrent Neural
Networks, every internal weight is fixed and only the last linear layer is
trained. They involve many multiplications by dense random matrices. Very large
networks are difficult to obtain, as the complexity scales quadratically both
in time and memory. Here, we present a novel optical implementation of
Echo-State Networks using light-scattering media and a Digital Micromirror
Device. As a proof of concept, binary networks have been successfully trained
to predict the chaotic Mackey-Glass time series. This new method is fast, power
efficient and easily scalable to very large networks.


title:
Mathematical design of a novel input/instruction device using a moving
  emitter

abstract:
  This paper is concerned with the mathematical design of a novel
input/instruction device using a moving emitter. The emitter generates a point
source and can be installed on a digit pen or worn on the finger of the human
being who wants to interact/communicate with the computer. The
input/instruction can be recognized by identifying the motion trajectory of the
emitter performed by the human being from the collected wave field data. The
identification process is modelled as an in- verse source problem where one
intends to identify the trajectory of a moving point source. There are several
salient features of our study which distinguish our result from the existing
ones in the literature. First, the point source is moving in an inhomogeneous
background medium, which models the human body. Second, the dynamical wave
field data are collected in a limited aperture. Third, the recon- struction
method is independent of the background medium, and it is totally direct
without any matrix inversion. Hence, it is efficient and robust with respect to
the measurement noise. Both theoretical justifications and computational
experiments are presented to verify our novel findings.


title: Quantum Eraser for Three-Slit Interference

abstract:
  It is well known that in a two-slit interference experiment, if the
information, on which of the two paths the particle followed, is stored in a
quantum path detector, the interference is destroyed. However, in a setup where
this path information is "erased", the interference can reappear. Such a setup
is known as a quantum eraser. A generalization of quantum eraser to a
three-slit interference is theoretically analyzed. It is shown that three
complementary interference patterns can arise out of the quantum erasing
process.


title: Geometric Nontermination Arguments

abstract:
  We present a new kind of nontermination argument, called geometric
nontermination argument. The geometric nontermination argument is a finite
representation of an infinite execution that has the form of a sum of several
geometric series. For so-called linear lasso programs we can decide the
existence of a geometric nontermination argument using a nonlinear algebraic
$\exists$-constraint. We show that a deterministic conjunctive loop program
with nonnegative eigenvalues is nonterminating if an only if there exists a
geometric nontermination argument. Furthermore, we present an evaluation that
demonstrates that our method is feasible in practice.


title:
Protostellar Outflows and Radiative Feedback from Massive Stars. II.
  Feedback, Star Formation Efficiency, and Outflow Broadening

abstract:
  We perform two-dimensional axially symmetric radiation-hydrodynamic
simulations to assess the impact of outflows and radiative force feedback from
massive protostars by varying when the protostellar outflow starts, the ratio
of ejection to accretion rates, and the strength of the wide angle disk wind
component. The star formation efficiency, i.e. the ratio of final stellar mass
to initial core mass, is dominated by radiative forces and the ratio of outflow
to accretion rates. Increasing this ratio has three effects: First, the
protostar grows slower with a lower luminosity at any given time, lowering
radiative feedback. Second, bipolar cavities cleared by the outflow are larger,
further diminishing radiative feedback on disk and core scales. Third, the
higher momentum outflow sweeps up more material from the collapsing envelope,
decreasing the protostar's potential mass reservoir via entrainment. The star
formation efficiency varies with the ratio of ejection to accretion rates from
50% in the case of very weak outflows to as low as 20% for very strong
outflows. At latitudes between the low density bipolar cavity and the high
density accretion disk, wide angle disk winds remove some of the gas, which
otherwise would be part of the accretion flow onto the disk; varying the
strength of these wide angle disk winds, however, alters the final star
formation efficiency by only +/-6%. For all cases, the opening angle of the
bipolar outflow cavity remains below 20 degree during early protostellar
accretion phases, increasing rapidly up to 65 degree at the onset of radiation
pressure feedback.


title: Violent Preheating in Inflation with Nonminimal Coupling

abstract:
  We study particle production at the preheating era in inflation models with
nonminimal coupling $\xi \phi^2R$ and quartic potential $\lambda \phi^4/4$ for
several cases: real scalar inflaton, complex scalar inflaton and Abelian Higgs
inflaton. We point out that the preheating proceeds much more violently than
previously thought. If the inflaton is a complex scalar, the phase degree of
freedom is violently produced at the first stage of preheating. If the inflaton
is a Higgs field, the longitudinal gauge boson production is similarly violent.
This is caused by a spike-like feature in the time dependence of the inflaton
field, which may be understood as a consequence of the short time scale during
which the effective potential or kinetic term changes suddenly. The produced
particles typically have very high momenta $k \lesssim
\sqrt{\lambda}M_\text{P}$. The production might be so strong that almost all
the energy of the inflaton is carried away within one oscillation for
$\xi^2\lambda \gtrsim {\mathcal O}(100)$. This may partly change the
conventional understandings of the (p)reheating after inflation with the
nonminimal coupling to gravity such as Higgs inflation. We also discuss the
possibility of unitarity violation at the preheating stage.


title:
A deep X-ray view of the bare AGN Ark 120. II. Evidence for Fe K
  emission transients

abstract:
  We report on the results from a large observational campaign on the bare
Seyfert galaxy Ark 120, jointly carried out in 2014 with XMM-Newton, Chandra,
and NuSTAR. The fortunate line of sight to this source, devoid of any
significant absorbing material, provides an incomparably clean view to the
nuclear regions of an active galaxy. Here we focus on the analysis of the iron
fluorescence features, which form a composite emission pattern in the 6$-$7 keV
band. The prominent K$\alpha$ line from neutral iron at 6.4 keV is resolved in
the Chandra High-Energy Transmission Grating spectrum to a full-width at half
maximum of 4700$^{+2700}_{-1500}$ km s$^{-1}$, consistent with an origin from
the optical broad-line region. Excess components are detected on both sides of
the narrow K$\alpha$ line: the red one (6.0$-$6.3 keV) clearly varies in
strength in about one year, and hints at the presence of a broad, mildly
asymmetric line from the accretion disk; the blue one (6.5$-$7.0 keV), instead,
is likely a blend of different contributions, and appears to be constant when
integrated over long enough exposures. However, the Fe K excess emission map
computed over the 7.5 days of the XMM-Newton monitoring shows that both the red
and the blue features are actually highly variable on timescales of
$\sim$10$-$15 hours, suggesting that they might arise from short-lived hotspots
on the disk surface, located within a few tens of gravitational radii from the
central supermassive black hole and possibly illuminated by magnetic
reconnection events. Any alternative explanation would still require a highly
dynamic, inhomogeneous disk/coronal system, involving clumpiness and/or
instability.


title:
SPT-GMOS: A Gemini/GMOS-South Spectroscopic Survey of Galaxy Clusters in
  the SPT-SZ Survey

abstract:
  We present the results of SPT-GMOS, a spectroscopic survey with the Gemini
Multi-Object Spectrograph (GMOS) on Gemini South. The targets of SPT-GMOS are
galaxy clusters identified in the SPT-SZ survey, a millimeter-wave survey of
2500 squ. deg. of the southern sky using the South Pole Telescope (SPT).
Multi-object spectroscopic observations of 62 SPT-selected galaxy clusters were
performed between January 2011 and December 2015, yielding spectra with radial
velocity measurements for 2595 sources. We identify 2243 of these sources as
galaxies, and 352 as stars. Of the galaxies, we identify 1579 as members of
SPT-SZ galaxy clusters. The primary goal of these observations was to obtain
spectra of cluster member galaxies to estimate cluster redshifts and velocity
dispersions. We describe the full spectroscopic dataset and resulting data
products, including galaxy redshifts, cluster redshifts and velocity
dispersions, and measurements of several well-known spectral indices for each
galaxy: the equivalent width, W, of [O II] 3727,3729 and H-delta, and the 4000A
break strength, D4000. We use the spectral indices to classify galaxies by
spectral type (i.e., passive, post-starburst, star-forming), and we match the
spectra against photometric catalogs to characterize spectroscopically-observed
cluster members as a function of brightness (relative to m*). Finally, we
report several new measurements of redshifts for ten bright, strongly-lensed
background galaxies in the cores of eight galaxy clusters. Combining the
SPT-GMOS dataset with previous spectroscopic follow-up of SPT-SZ galaxy
clusters results in spectroscopic measurements for >100 clusters, or ~20% of
the full SPT-SZ sample.


title:
Optical spectroscopic observations of $\gamma$-ray blazar candidates VI.
  Further observations from TNG, WHT, OAN, SOAR and Magellan telescopes

abstract:
  Blazars, one of the most extreme class of active galaxies, constitute so far
the largest known population of $\gamma$-ray sources and their number is
continuously growing in the Fermi catalogs. However in the latest release of
the Fermi catalog there is still a large fraction of sources that are
classified as blazar candidate of uncertain type (BCUs) for which optical
spectroscopic observations are necessary to confirm their nature and their
associations. In addition about 1/3 of the $\gamma$-ray point sources listed in
the Third Fermi-LAT Source Catalog (3FGL) are still unassociated and lacking an
assigned lower energy counterpart. Since 2012 we have been carrying out an
optical spectroscopic campaign to observe blazar candidates to confirm their
nature. In this paper, the sixth of the series, we present optical
spectroscopic observations for 30 $\gamma$-ray blazar candidates from different
observing programs we carried out with the TNG, WHT, OAN, SOAR and Magellan
telescopes. We found that 21 out of 30 sources investigated are BL Lac objects
while the remaining targets are classified as flat spectrum radio quasars
showing the typical broad emission lines of normal quasi stellar objects. We
conclude that our selection of $\gamma$-ray blazars candidates based on their
multifrequency properties continues to be a successful way to discover
potential low-energy counterparts of the FermiUnidentified Gamma-ray Sources
(UGSs) and to confirm the nature of BCUs.


title:
Chiral Soliton Lattice and Charged Pion Condensation in Strong Magnetic
  Fields

abstract:
  The Chiral Soliton Lattice (CSL) is a state with a periodic array of
topological solitons that spontaneously breaks parity and translational
symmetries. Such a state is known to appear in chiral magnets. We show that CSL
also appears as a ground state of quantum chromodynamics at nonzero chemical
potential in a magnetic field. By analyzing the fluctuations of the CSL, we
furthermore demonstrate that in strong but achievable magnetic fields, charged
pions undergo Bose-Einstein condensation. Our results, based on a systematic
low-energy effective theory, are model-independent and fully analytic.


title:
The oldest and most metal poor stars in the APOSTLE Local Group
  simulations

abstract:
  We examine the spatial distribution of the oldest and most metal poor stellar
populations of Milky Way-sized galaxies using the APOSTLE cosmological
hydrodynamical simulations of the Local Group. In agreement with earlier work,
we find strong radial gradients in the fraction of the oldest (tform < 0.8 Gyr)
and most metal poor ([Fe/H]< -2.5) stars, both of which increase outwards. The
most metal poor stars form over an extended period of time; half of them form
after z = 5.3, and the last 10% after z = 2.8. The age of the metal poor
stellar population also shows significant variation with environment; a high
fraction of them are old in the galaxy's central regions and an even higher
fraction in some individual dwarf galaxies, with substantial scatter from dwarf
to dwarf. Overall, over half of the stars that belong to both the oldest and
most metal-poor population are found outside the solar circle. Somewhat
counter-intuitively, we find that dwarf galaxies with a large fraction of metal
poor stars that are very old are systems where metal poor stars are relatively
rare, but where a substantial old population is present. Our results provide
guidance for interpreting the results of surveys designed to hunt for the
earliest and most pristine stellar component of our Milky Way.


title:
Babel Routing Protocol for OMNeT++ - More than just a new simulation
  module for INET framework

abstract:
  Routing and switching capabilities of computer networks seem as the closed
environment containing a limited set of deployed protocols, which nobody dares
to change. The majority of wired network designs are stuck with OSPF
(guaranteeing dynamic routing exchange on network layer) and RSTP (securing
loop-free data-link layer topology). Recently, more use-case specific routing
protocols, such as Babel, have appeared. These technologies claim to have
better characteristic than current industry standards. Babel is a fresh
contribution to the family of distance-vector routing protocols, which is
gaining its momentum for small double-stack (IPv6 and IPv4) networks. This
paper briefly describes Babel behavior and provides details on its
implementation in OMNeT++ discrete event simulator.


title: Measurement of matter-antimatter differences in beauty baryon decays

abstract:
  Differences in the behaviour of matter and antimatter have been observed in
$K$ and $B$ meson decays, but not yet in any baryon decay. Such differences are
associated with the non-invariance of fundamental interactions under the
combined charge-conjugation and parity transformations, known as $C\!P$
violation. Using data from the LHCb experiment at the Large Hadron Collider, a
search is made for $C\!P$-violating asymmetries in the decay angle
distributions of $\Lambda^0_b$ baryons decaying to $p\pi^-\pi^+\pi^-$ and
$p\pi^-K^+K^-$ final states. These four-body hadronic decays are a promising
place to search for sources of $C\!P$ violation both within and beyond the
Standard Model of particle physics. We find evidence for $C\!P$ violation in
$\Lambda^0_b$ to $p\pi^-\pi^+\pi^-$ decays with a statistical significance
corresponding to 3.3 standard deviations including systematic uncertainties.
This represents the first evidence for $C\!P$ violation in the baryon sector.


title: Many-body Lattice Wavefunctions From Conformal Blocks

abstract:
  We introduce a general framework to construct many-body lattice wavefunctions
starting from the conformal blocks (CBs) of rational conformal field theories
(RCFTs). We discuss the different ways of encoding the physical degrees of
freedom of the lattice system using both the internal symmetries of the theory
and the fusion channels of the CBs. We illustrate this construction both by
revisiting the known Haldane-Shastry model and by providing a novel
implementation for the Ising RCFT. In the latter case, we find a connection to
the Ising transverse field (ITF) spin chain via the Kramers-Wannier duality and
the Temperley-Lieb-Jones algebra. We also find evidence that the ground state
of the finite-size critical ITF Hamiltonian corresponds exactly to the
wavefunction obtained from CBs of spin fields.


title: On the Coupling of Photon Spin to Electron Orbital Angular Momentum

abstract:
  Partially gold coated 90 degree glass wedges and a semi - infinite slit in a
thin film of gold ending in a conducting nano-junction serve as samples to
investigate the transfer of photon spin to electron orbital angular momentum.
These structures were specifically designed as samples where an incident beam
of light is retroreflected. Since in the process of retroreflection the turning
sense of a circularly polarized beam of light does not change and the direction
of propagation is inverted, the photon spin is inverted. Due to conservation of
angular momentum a transfer of photon spin to electron orbital angular momentum
of conduction electrons occurs. In the structures a circular movement of
electrons is blocked and therefore the transfered spin can be detected as a
photovoltage due to an electromotive force which is induced by the transfer of
angular momentum. Depending on the polarization of the incident beam, a maximum
photovoltage of about 0,2 micro V was measured for both structures. The results
are interpreted in terms of a classical electrodynamic model of the
monochromatic linearly polarized photon as a propagating solitary
electromagnetic wave of finite energy hf which carries an angular momentum
h/2pi which is elaborated elsewhere where h is Plancks constant and f the
frequency of light. The relative values of the measured photovoltages for
different polarizations can well be explained by the electrodynamic model of a
photon and an associated spin angular momentum. The absolute values of the
measured photovoltages are also consistent with the interpretation. The
observed effects are closely related to the lateral Fedorov Imbert shift of
focused beams in optics and the optical spin Hall effect and to other non
linear optical effects such as the inverse faraday effect for which a new
interpretation is given here in terms of the electrodynamic model of the photon
and its spin.


title: Hurwitz numbers for real polynomials

abstract:
  We consider the problem of defining and computing real analogs of polynomial
Hurwitz numbers, in other words, the problem of counting properly normalized
real polynomials with fixed ramification profiles over real branch points. We
show that, provided the polynomials are counted with an appropriate sign, their
number does not depend on the order of the branch points on the real line. We
study generating series for the invariants thus obtained, determine necessary
and sufficient conditions for the vanishing and nonvanishing of these
generating series, and obtain a logarithmic asymptotic for the invariants as
the degree of the polynomials tends to infinity.


title:
Constructing the Hyperbolic Plane as the reduction of a three-body
  problem

abstract:
  We construct the hyperbolic plane with its geodesic flow as the scale plus
symmetry reduction of a three-body problem in the Euclidean plane. The
potential is $-I/\Delta^2$ where $I$ is the triangle's moment of inertia and
$\Delta$ its area. The reduction method uses the Jacobi-Maupertuis metric,
following the author's earlier paper "Putting Hyperbolic Pants on a Three-body
Problem".


title: Logical compactness and constraint satisfaction problems

abstract:
  We investigate a correspondence between the complexity hierarchy of
constraint satisfaction problems and a hierarchy of logical compactness
hypotheses for finite relational structures. It seems that the harder a
constraint satisfaction problem is, the stronger the corresponding compactness
hypothesis is. At the top level, the NP-complete constraint satisfaction
problems correspond to compactness hypotheses that are equivalent to the
ultrafilter axiom in all the cases we have investigated. At the bottom level,
the simplest constraint satisfaction problems correspond to compactness
hypotheses that are readily provable from the axioms of Zermelo and Fraenkel.


title: What prevents gravitational collapse in string theory?

abstract:
  It is conventionally believed that if a ball of matter of mass $M$ has a
radius close to $2GM$ then it must collapse to a black hole. But string theory
microstates (fuzzballs) have no horizon or singularity, and they do {\it not}
collapse. We consider two simple examples from classical gravity to illustrate
how this violation of our intuition happens. In each case the `matter' arises
from an extra compact dimension, but the topology of this extra dimension is
not trivial. The pressure and density of this matter diverge at various points,
but this is only an artifact of dimensional reduction; thus we bypass results
like Buchadahl's theorem. Such microstates give the entropy of black holes, so
these topologically nontrivial constructions dominate the state space of
quantum gravity.


title: Ultrafast photo-magnetic recording in transparent medium

abstract:
  Finding a conceptually new way to control the magnetic state of media with
the lowest possible production of heat and simultaneously at the fastest
possible time-scale is a new challenge in fundamental magnetism [1-4] as well
as an increasingly important issue in modern information technology [5]. Recent
results demonstrate that exclusively in metals it is possible to switch
magnetization between metastable states by femtosecond circularly polarized
laser pulses [6-8]. However, despite the record breaking speed of the
switching, the mechanisms in these materials are directly related to strong
optical absorption and laser-induced heating close to the Curie temperature
[9-12]. Here we report about ultrafast all-optical photo-magnetic recording in
transparent dielectrics. In ferrimagnetic garnet film a single linearly
polarized femtosecond laser pulse breaks the degeneracy between metastable
magnetic states and promotes switching of spins between them. Changing the
polarization of the laser pulse we deterministically steer the net
magnetization in the garnet, write "0" and "1" magnetic bits at will. This
mechanism operates at room temperature and allows ever fastest write-read
magnetic recording event (< 20 ps) accompanied by unprecedentedly low heat load
(< 6 J/cm3).


title:
Prioritised Default Logic as Argumentation with Partial Order Default
  Priorities

abstract:
  We express Brewka's prioritised default logic (PDL) as argumentation using
ASPIC+. By representing PDL as argumentation and designing an argument
preference relation that takes the argument structure into account, we prove
that the conclusions of the justified arguments correspond to the PDL
extensions. We will first assume that the default priority is total, and then
generalise to the case where it is a partial order. This provides a
characterisation of non-monotonic inference in PDL as an exchange of argument
and counter-argument, providing a basis for distributed non-monotonic reasoning
in the form of dialogue.


title: Autonomous Orbit Determination via Kalman Filtering of Gravity Gradients

abstract:
  Spaceborne gravity gradients are proposed in this paper to provide autonomous
orbit determination capabilities for near Earth satellites. The gravity
gradients contain useful position information which can be extracted by
matching the observations with a precise gravity model. The extended Kalman
filter is investigated as the principal estimator. The stochastic model of
orbital motion, the measurement equation and the model configuration are
discussed for the filter design. An augmented state filter is also developed to
deal with unknown significant measurement biases. Simulations are conducted to
analyze the effects of initial errors, data-sampling periods, orbital heights,
attitude and gradiometer noise levels, and measurement biases. Results show
that the filter performs well with additive white noise observation errors.
Degraded observability for the along-track position is found for the augmented
state filter. Real flight data from the GOCE satellite are used to test the
algorithm. Radial and cross-track position errors of less than 100 m have been
achieved.


title:
Simulations of Energetic Particles Interacting with Nonlinear
  Anisotropic Dynamical Turbulence

abstract:
  We investigate test-particle diffusion in dynamical turbulence based on a
numerical approach presented before. For the turbulence we employ the nonlinear
anisotropic dynamical turbulence model which takes into account wave
propagation effects as well as damping effects. We compute numerically
diffusion coefficients of energetic particles along and across the mean
magnetic field. We focus on turbulence and particle parameters which should be
relevant for the solar system and compare our findings with different
interplanetary observations. We vary different parameters such as the
dissipation range spectral index, the ratio of the turbulence bendover scales,
and the magnetic field strength in order to explore the relevance of the
different parameters. We show that the bendover scales as well as the magnetic
field ratio have a strong influence on diffusion coefficients whereas the
influence of the dissipation range spectral index is weak. The best agreement
with solar wind observations can be found for equal bendover scales and a
magnetic field ratio of $\delta$B/B0 = 0.75.


title:
The implicit contribution of slab modes to the perpendicular diffusion
  coefficient of particles interacting with two-component turbulence

abstract:
  We explore the transport of energetic particles in two-component turbulence
in which the stochastic magnetic field is assumed to be a superposition of slab
and two-dimensional modes. It is known that in magnetostatic slab turbulence,
the motion of particles across the mean magnetic field is subdiffusive. If a
two-dimensional component is added, diffusion is recovered. It was also shown
before that in two-component turbulence, the slab modes do not explicitly
contribute to the perpendicular diffusion coefficient. In the current paper the
implicit contribution of slab modes is explored and it is shown that this
contribution leads to a reduction of the perpendicular diffusion coefficient.
This effect improves the agreement between simulations and analytical theory.
Furthermore, the obtained results are relevant for investigations of diffusive
shock acceleration.


title: Continuous occurrence theory

abstract:
  Usually gradual and continuous changes in entities will lead to appear
events. But usually it is supposed that an event is occurred at once. In this
research an integrated framework called continuous occurrence theory (COT) is
presented to investigate respective path leading to occurrence of the events in
the real world. For this purpose initially fundamental concepts are defined.
Afterwards, the appropriate tools such as occurrence variables computations,
occurrence dependency function and occurrence model are introduced and
explained in a systematic manner. Indeed, COT provides the possibility to: (a)
monitor occurrence of events during time; (b) study background of the events;
(c) recognize the relevant issues of each event; and (d) understand how these
issues affect on the considered event. The developed framework (COT) provides
the necessary context to analyze accurately continual changes of the issues and
the relevant events in the various branches of science and business. Finally,
typical applications of COT and an applied modeling example of it have been
explained and a mathematical programming example is modeled in the occurrence
based environment.


title:
Magnetophonon oscillations of thermoelectric power and combined
  resonance in two-subband electron systems

abstract:
  By measuring the thermoelectric effect in high-mobility quantum wells with
two occupied subbands in perpendicular magnetic field, we detect magnetophonon
oscillations due to interaction of electrons with acoustic phonons. These
oscillations contain specific features identified as combined resonances caused
by intersubband phonon-assisted transitions of electrons in the presence of
Landau quantization. The quantum theory of phonon-drag magnetothermoelectric
effect, generalized to the case of multi-subband occupation, describes our
experimental findings.


title:
Addressing the lattice stability puzzle in the computational
  determination of intermetallic phase diagrams

abstract:
  The evaluation of phase stabilities of unstable elemental phases is a
long-standing problem in the computational assessment of phase diagrams. Here
we tackle this problem by explicitly calculating phase diagrams of
intermetallic systems where its effect should be most conspicuous, binary
systems of titanium with bcc transition metals (Mo, Nb, Ta and V). Two types of
phase diagrams are constructed: one based on the lattice stabilities extracted
from empirical data, and the other using the lattice stabilities computed from
first principles. It is shown that the phase diagrams obtained using the
empirical values contain clear contradictions with the experimental phase
diagrams at the well known limits of low or high temperatures. Realistic phase
diagrams, with a good agreement with the experimental observations, are
achieved only when the computed lattice stability values are used. At
intermediate temperatures, the computed phase diagrams resolve the controversy
regarding the shape of the solvus in these systems, predicting a complex
structure with a eutectoid transition and a miscibility gap between two bcc
phases.


title:
Diffusion Coefficients Estimation for Elliptic Partial Differential
  Equations

abstract:
  This paper considers the Dirichlet problem $$ -\mathrm{div}(a\nabla u_a)=f
\quad \hbox{on}\,\,\ D, \qquad u_a=0\quad \hbox{on}\,\,\partial D, $$ for a
Lipschitz domain $D\subset \mathbb R^d$, where $a$ is a scalar diffusion
function. For a fixed $f$, we discuss under which conditions is $a$ uniquely
determined and when can $a$ be stably recovered from the knowledge of $u_a$.
  A first result is that whenever $a\in H^1(D)$, with $0<\lambda \le a\le
\Lambda$ on $D$, and $f\in L_\infty(D)$ is strictly positive, then $$
\|a-b\|_{L_2(D)}\le C\|u_a-u_b\|_{H_0^1(D)}^{1/6}. $$ More generally, it is
shown that the assumption $a\in H^1(D)$ can be weakened to $a\in H^s(D)$, for
certain $s<1$, at the expense of lowering the exponent $1/6$ to a value that
depends on $s$.


title:
Ensemble master equation for a trapped-atom clock with one- and two-body
  losses

abstract:
  An ensemble density matrix model that includes one- and two-body losses is
derived for a trapped-atom clock. A trapped-atom clock is mainly affected by
one- and two-body losses, generally giving nonexponential decays of
populations; nevertheless, three-body recombination is also quantitatively
analyzed to demonstrate the boundaries of its practical relevance. The
importance of one-body losses is highlighted without which population trapping
behavior would be observed. The model is written with decay constants expressed
through experimental parameters. It can complement, e.g., the ISRE (identical
spin rotation effect) model to improve its predictions: ISRE dramatically
increases the ensemble coherence time, hence it enables one to observe the
influence of two-body losses on the interferometry contrast envelope. The
presented model is useful for Ramsey interferometry and is ready for immediate
experimental verification in existing systems.


title:
Inferring the interplanetary dust properties from remote observations
  and simulations

abstract:
  Since in situ studies and interplanetary dust collections only provide a
spatially limited amount of information about the interplanetary dust
properties, it is of major importance to complete these studies with properties
inferred from remote observations of light scattered and emitted, with
interpretation through simulations. Physical properties of the interplanetary
dust in the near-ecliptic symmetry surface, such as the local polarization,
temperature and composition, together with their heliocentric variations, may
be derived from scattered and emitted light observations, giving clues to the
respective contribution of the particles sources. A model of light scattering
by a cloud of solid particles constituted by spheroidal grains and aggregates
thereof is used to interpret the local light scattering data. Equilibrium
temperature of the same particles allows us to interpret the temperature
heliocentric variations. A good fit of the local polarization phase curve,
$P_{\alpha}$, near 1.5~AU from the Sun is obtained for a mixture of silicates
and more absorbing organics material ($\approx$40 % in mass) and for a
realistic size distribution typical of the interplanetary dust in the 0.2 to
200 micrometre size range. The contribution of dust particles of cometary
origin is at least 20% in mass. The same size distribution of particles gives a
solar distance, $R$, dependence of the temperature in $R^{-0.45}$ different
than the typical black body behavior. The heliocentric dependence of
$P_{\alpha=90{\deg}}$ is interpreted as a progressive disappearance of solid
organics (such as HCN polymers or amorphous carbon) towards the Sun.


title: Interactive Spoken Content Retrieval by Deep Reinforcement Learning

abstract:
  User-machine interaction is important for spoken content retrieval. For text
content retrieval, the user can easily scan through and select on a list of
retrieved item. This is impossible for spoken content retrieval, because the
retrieved items are difficult to show on screen. Besides, due to the high
degree of uncertainty for speech recognition, the retrieval results can be very
noisy. One way to counter such difficulties is through user-machine
interaction. The machine can take different actions to interact with the user
to obtain better retrieval results before showing to the user. The suitable
actions depend on the retrieval status, for example requesting for extra
information from the user, returning a list of topics for user to select, etc.
In our previous work, some hand-crafted states estimated from the present
retrieval results are used to determine the proper actions. In this paper, we
propose to use Deep-Q-Learning techniques instead to determine the machine
actions for interactive spoken content retrieval. Deep-Q-Learning bypasses the
need for estimation of the hand-crafted states, and directly determine the best
action base on the present retrieval status even without any human knowledge.
It is shown to achieve significantly better performance compared with the
previous hand-crafted states.


title:
RFM-SLAM: Exploiting Relative Feature Measurements to Separate
  Orientation and Position Estimation in SLAM

abstract:
  The SLAM problem is known to have a special property that when robot
orientation is known, estimating the history of robot poses and feature
locations can be posed as a standard linear least squares problem. In this
work, we develop a SLAM framework that uses relative feature-to-feature
measurements to exploit this structural property of SLAM. Relative feature
measurements are used to pose a linear estimation problem for pose-to-pose
orientation constraints. This is followed by solving an iterative non-linear
on-manifold optimization problem to compute the maximum likelihood estimate for
robot orientation given relative rotation constraints. Once the robot
orientation is computed, we solve a linear problem for robot position and map
estimation. Our approach reduces the computational burden of non-linear
optimization by posing a smaller optimization problem as compared to standard
graph-based methods for feature-based SLAM. Further, empirical results show our
method avoids catastrophic failures that arise in existing methods due to using
odometery as an initial guess for non-linear optimization, while its accuracy
degrades gracefully as sensor noise is increased. We demonstrate our method
through extensive simulations and comparisons with an existing state-of-the-art
solver.


title: Minimal plane valuations

abstract:
  We consider the last value $\hat{\mu} (\nu)$ of the vanishing sequence of
$H^0(L)$ along a divisorial or irrational valuation $\nu$ centered at
$\mathcal{O}_{\mathbb{P}^2,p}$, where $L$ resp. $p$ is a line resp. a point of
the projective plane $\mathbb{P}^2$ over an algebraically closed field. This
value contains, for valuations, similar information as that given by Seshadri
constants for points. It is always true that $\hat{\mu} (\nu) \geq \sqrt{1 /
\mathrm{vol}(\nu)}$ and minimal valuations are those satisfying the equality.
In this paper, we prove that the Greuel-Lossen-Shustin Conjecture implies a
variation of the Nagata Conjecture involving minimal valuations (that extends
the one stated in the paper "Very general monomial valuations of $\mathbb{P}^2$
and a Nagata type conjecture" by Dumnicki et al. to the whole set of divisorial
and irrational valuations of the projective plane) which also implies the
original one. We also provide infinitely many families of very general minimal
valuations with an arbitrary number of Puiseux exponents, and an asymptotic
result that can be considered as an evidence in the direction of the mentioned
conjecture by Dumnicki et al.


title:
Cosmic dust optical properties: Numerical simulations and future
  laboratory measurements in microgravity

abstract:
  Understanding the properties of particle aggregation and resulting aggregates
under microgravity conditions leads to better insights on the formation of the
early Solar System planetesimals. Simulating such conditions is the main
objective of Interactions in Cosmic and Atmospheric Particle System (ICAPS), a
multi-users facility currently under phase B at ESA for the International Space
Station. First results of light scattering simulations by core-mantle
aggregates of grains with organics and icy mantles are presented to show the
evolution of polarization with aggregation. The Light Scattering Unit is both a
polarization diagnostic tool for ICAPS, and an experiment that will allow the
interpretation of the available light scattering dust observations in terms of
physical properties of the scattering media. This presentation updates the
current approach of the calibration procedures and the innovative experimental
setup (providing a phase angle exploration from about 2{\deg} to 175{\deg}
together with a wavelength exploration from 0.4 to 0.8 micrometer). We also
assess the possibility for the determination of the entire Stokes vector of the
light scattered by the aggregates.


title:
Comment on "Linear Scaling of the Exciton Binding Energy versus the Band
  Gap of Two-Dimensional Materials"

abstract:
  In a recent letter [J. -H. Choi et al. Phys. Rev. Lett. 115, 066403 (2015)],
a universal linear relation between the binding energy Eb of exciton and the
band gap Eg is found in different quasi-2D semiconductors. However, when one
extrapolates the straight line to Eg=0, a positive Eb is obtained. This means
that a stable exciton exists in a metal (Eg=0), or in other words, the
excitation energy is negative. Therefore, for quasi-2D semiconductors with
small band gap, Eb vs. Eg must deviate from the straight line suggested in the
Letter.
  We performed similar GW+BSE calculation as the Letter for compressed
phosphorene and stretched graphene. At larger band gap, our data fall in the
same straight lien as the Letter. But for the quasi-2D semiconductors with
small band gap, the Eb vs. Eg curve approaches to zero. A simple model based on
local instantaneous screened interaction gives reasonable agreement with the
more rigorous calculations. For the quasi-2D semiconductors with diminishing
gap Eg<0.3eV, due to the nonlocal retarded effect induced by the strong
screening in the small gap materials, one has to use 2-time transition
amplitude (Bethe-Salpeter wave function) to describe exciton.


title:
Charge-density-wave state induced by structural distortion in
  heavy-fermion compounds Ce$_3$M$_4$Sn$_{13}$ (M=Co, Ru, Rh)

abstract:
  In previous reports a structural transition from a cubic phase of
Yb$_3$Rh$_4$Sn$_{13}$ - type to the superlattice variant has been reported at
$\sim160$ K for a series of skutterudite-related Ce$_3$M$_4$Sn$_{13}$
compounds, where M=Co, Ru or Rh. We have simulated the low-temperature XRD
diffraction patterns of the distorted unit cell using written for that purpose
DISTorX program. The method proposed here for x-ray diffraction analysis
obtains the XRD patterns from the atomic positions and allows to investigate
crystal structure without imposed symmetry operations. We have indicated
crystallographic plane where distortion occurs and explained possible origin of
CDW in these materials. We have also shown that distortion caused by the charge
density wave leads to significantly changes of the intensity of diffraction
lines.


title: A Computation in a Cellular Automaton Collider Rule 110

abstract:
  A cellular automaton collider is a finite state machine build of rings of
one-dimensional cellular automata. We show how a computation can be performed
on the collider by exploiting interactions between gliders (particles,
localisations). The constructions proposed are based on universality of
elementary cellular automaton rule 110, cyclic tag systems, supercolliders, and
computing on rings.


title:
Thermal fluctuations of the Josephson current in a ring of
  superconducting grains

abstract:
  Thermal fluctuations of the Josephson current $I$ induced by the magnetic
flux through a ring of $N$ superconducting grains are studied. When a
half-fluxon is threading the ring, $I$ exhibits incoherent transitions between
the two degenerate states due to thermal phase slips. We propose a new
numerical method to deal with both equilibrium and dynamic properties of
Josephson systems. Computed transition rate has the form $\Gamma =
A(N)\exp[-B(N)/T]$, where $B(N)$ agrees with the analytical result derived for
the energy barrier associated with phase slips. In the non-degenerate case
(e.g., at a quarter-fluxon) the equilibrium value of $I$ decreases with $T$ due
to harmonic excitations and then gets destroyed by phase slips.


title:
Micropatterned Charge Heterogeneities via Vapor Deposition of
  Aminosilanes

abstract:
  Aminosilanes are routinely employed for charge reversal or to create coupling
layers on oxide surfaces. We present a chemical vapor deposition method to
pattern mica surfaces with regions of high-quality aminosilane
(3-aminopropyltriethoxysilane, APTES) monolayers. The approach relies on the
vapor deposition of an aminosilane through a patterned array of through-holes
in a PDMS (poly(dimethylsiloxane)) membrane that acts as a mask. In aqueous
solutions the surfaces have regular patterns of charge heterogeneities with
minimal topographical variations over large areas. This versatile dry lift-off
deposition method alleviates issues with multilayer formation and can be used
to create charge patterns on curved surfaces. We identify the necessary steps
to achieve high quality monolayers and charge reversal of the underlying mica
surface: 1) hexane extraction to remove unreacted PDMS oligomers from the
membrane that would otherwise deposit on and contaminate the substrate, 2)
oxygen plasma treatment of the top of the membrane surfaces to generate a
barrier layer that blocks APTES transport through the PDMS, and 3) decrease of
the vapor pressure of APTES during deposition to minimize APTES condensation at
the mica-membrane-vapor contact lines and to prevent multilayer formation.
Under these conditions, AFM imaging shows that the monolayers have a height of
0.9nm with an increase in height up to 3nm at the mica-membrane-vapor contact
lines. Fluorescence imaging demonstrates pattern fidelity on both flat and
curved surfaces, for feature sizes that vary between 6.5-40 um. We verify
charge reversal by measuring the double layer forces between a homogeneous
APTES monolayers and a mica surface in aqueous solution and we characterize the
surface potential of APTES monolayers by measuring the double layer forces
between identical APTES surfaces. We obtain a surface potential of 110mV at pH
4.0.


title: Fast Second-order Cone Programming for Safe Mission Planning

abstract:
  This paper considers the problem of safe mission planning of dynamic systems
operating under uncertain environments. Much of the prior work on achieving
robust and safe control requires solving second-order cone programs (SOCP).
Unfortunately, existing general purpose SOCP methods are often infeasible for
real-time robotic tasks due to high memory and computational requirements
imposed by existing general optimization methods. The key contribution of this
paper is a fast and memory-efficient algorithm for SOCP that would enable
robust and safe mission planning on-board robots in real-time. Our algorithm
does not have any external dependency, can efficiently utilize warm start
provided in safe planning settings, and in fact leads to significant speed up
over standard optimization packages (like SDPT3) for even standard SOCP
problems. For example, for a standard quadrotor problem, our method leads to
speedup of 1000x over SDPT3 without any deterioration in the solution quality.
  Our method is based on two insights: a) SOCPs can be interpreted as
optimizing a function over a polytope with infinite sides, b) a linear function
can be efficiently optimized over this polytope. We combine the above
observations with a novel utilization of Wolfe's algorithm to obtain an
efficient optimization method that can be easily implemented on small embedded
devices. In addition to the above mentioned algorithm, we also design a
two-level sensing method based on Gaussian Process for complex obstacles with
non-linear boundaries such as a cylinder.


title:
Select-Additive Learning: Improving Generalization in Multimodal
  Sentiment Analysis

abstract:
  Multimodal sentiment analysis is drawing an increasing amount of attention
these days. It enables mining of opinions in video reviews which are now
available aplenty on online platforms. However, multimodal sentiment analysis
has only a few high-quality data sets annotated for training machine learning
algorithms. These limited resources restrict the generalizability of models,
where, for example, the unique characteristics of a few speakers (e.g., wearing
glasses) may become a confounding factor for the sentiment classification task.
In this paper, we propose a Select-Additive Learning (SAL) procedure that
improves the generalizability of trained neural networks for multimodal
sentiment analysis. In our experiments, we show that our SAL approach improves
prediction accuracy significantly in all three modalities (verbal, acoustic,
visual), as well as in their fusion. Our results show that SAL, even when
trained on one dataset, achieves good generalization across two new test
datasets.


title:
Improved Control Strategies for Intermittent Contact Mode Atomic Force
  Microscopes

abstract:
  Atomic force microscopes have proved to be fundamental research tools in many
situations where a gentle imaging process is required, and in a variety of
environmental conditions, such as the study of biological samples. Among the
possible modes of operation, intermittent contact mode is one that causes less
wear to both the sample and the instrument; therefore, it is ideal when imaging
soft samples. However, intermittent contact mode is not particularly fast when
compared to other imaging strategies. In this paper, we introduce three
enhanced control approaches, applied at both the dither and z-axis piezos, to
address the limitations of existing control schemes. Our proposed strategies
are able to eliminate different image artefacts, automatically adapt scan speed
to the sample being scanned and predict its features in real time. The result
is that both the image quality and the scan time are improved.


title:
Determination of pulsation periods and other parameters of 2875 stars
  classified as MIRA in the All Sky Automated Survey (ASAS)

abstract:
  We have developed an interactive PYTHON code and derived crucial ephemeris
data of 99.4% of all stars classified as 'Mira' in the ASAS data base,
referring to pulsation periods, mean maximum magnitudes and, whenever possible,
the amplitudes among others. We present a statistical comparison between our
results and those given by the AAVSO International Variable Star Index (VSX),
as well as those determined with the machine learning automatic procedure of
Richards et al. 2012. Our periods are in good agreement with those of the VSX
in more than 95% of the stars. However, when comparing our periods with those
of Richards et al, the coincidence rate is only 76% and most of the remaining
cases refer to aliases. We conclude that automatic codes require still more
refinements in order to provide reliable period values. Period distributions of
the target stars show three local maxima around 215, 275 and 330 d, apparently
of universal validity, their relative strength seems to depend on galactic
longitude. Our visual amplitude distribution turns out to be bimodal, however
1/3 of the targets have rather small amplitudes (A $<$ 2.5$^{m}$) and could
refer to semi-regular variables (SR). We estimate that about 20% of our targets
belong to the SR class. We also provide a list of 63 candidates for period
variations and a sample of 35 multiperiodic stars which seem to confirm the
universal validity of typical sequences in the double period and in the
Petersen diagrams


title: Viewpoint Selection for Grasp Detection

abstract:
  In grasp detection, the robot estimates the position and orientation of
potential grasp configurations directly from sensor data. This paper explores
the relationship between viewpoint and grasp detection performance.
Specifically, we consider the scenario where the approximate position and
orientation of a desired grasp is known in advance and we want to select a
viewpoint that will enable a grasp detection algorithm to localize it more
precisely and with higher confidence. Our main findings are that the right
viewpoint can dramatically increase the number of detected grasps and the
classification accuracy of the top-n detections. We use this insight to create
a viewpoint selection algorithm and compare it against a random viewpoint
selection strategy and a strategy that views the desired grasp head-on. We find
that the head-on strategy and our proposed viewpoint selection strategy can
improve grasp success rates on a real robot by 8% and 4%, respectively.
Moreover, we find that the combination of the two methods can improve grasp
success rates by as much as 12%.