title: Simple Search Algorithms on Semantic Networks Learned from Language Use

abstract:
  Recent empirical and modeling research has focused on the semantic fluency
task because it is informative about semantic memory. An interesting interplay
arises between the richness of representations in semantic memory and the
complexity of algorithms required to process it. It has remained an open
question whether representations of words and their relations learned from
language use can enable a simple search algorithm to mimic the observed
behavior in the fluency task. Here we show that it is plausible to learn rich
representations from naturalistic data for which a very simple search algorithm
(a random walk) can replicate the human patterns. We suggest that explicitly
structuring knowledge about words into a semantic network plays a crucial role
in modeling human behavior in memory search and retrieval; moreover, this is
the case across a range of semantic information sources.


title: Computing Distances between Reach Flowpipes

abstract:
  We investigate quantifying the difference between two hybrid dynamical
systems under noise and initial-state uncertainty. While the set of traces for
these systems is infinite, it is possible to symbolically approximate trace
sets using \emph{reachpipes} that compute upper and lower bounds on the
evolution of the reachable sets with time. We estimate distances between
corresponding sets of trajectories of two systems in terms of distances between
the reachpipes.
  In case of two individual traces, the Skorokhod distance has been proposed as
a robust and efficient notion of distance which captures both value and timing
distortions. In this paper, we extend the computation of the Skorokhod distance
to reachpipes, and provide algorithms to compute upper and lower bounds on the
distance between two sets of traces. Our algorithms use new geometric insights
that are used to compute the worst-case and best-case distances between two
polyhedral sets evolving with time.


title:
Ground-State Energy as a Simple Sum of Orbital Energies in Kohn-Sham
  Theory: A Shift in Perspective through a Shift in Potential

abstract:
  It is observed that the exact interacting ground-state electronic energy of
interest may be obtained directly, in principle, as a simple sum of orbital
energies when a universal density-dependent term is added to $w\left(\left[
\rho \right];\mathbf{r} \right)$, the familiar Hartree plus
exchange-correlation component in the Kohn-Sham effective potential. The
resultant shifted potential, $\bar{w}\left(\left[ \rho \right];\mathbf{r}
\right)$, actually changes less on average than $w\left(\left[ \rho
\right];\mathbf{r} \right)$ when the density changes, including the fact that
$\bar{w}\left(\left[ \rho \right];\mathbf{r} \right)$ does not undergo a
discontinuity when the number of electrons increases through an integer. Thus
the approximation of $\bar{w}\left(\left[ \rho \right];\mathbf{r} \right)$
represents an alternative direct approach for the approximation of the
ground-state energy and density.


title:
Nonlinear charge transport in bipolar semiconductors due to electron
  heating

abstract:
  It is known that when strong electric field is applied to a semiconductor
sample, the current voltage characteristic deviates from the linear response.
In this letter, we propose a new point of view of nonlinearity in
semiconductors which is associated with the electron temperature dependence on
the recombination rate. The heating of the charge carriers breaks the balance
between generation and recombination, giving rise to nonequilibrium charge
carriers concentration and nonlinearity.


title: Perfect valley filter in strained graphene with single barrier region

abstract:
  We present a single barrier system to generate pure valley-polarized current
in monolayer graphene. A uniaxial strain is applied within the barrier region,
which is delineated by localized magnetic field created by ferromagnetic
stripes at the regions boundaries. We show that under the condition of matching
magnetic field strength, strain potential, and Fermi energy, the transmitted
current is composed of only one valley contribution. The desired valley current
can transmit with zero reflection while the electrons from the other valley are
totally reflected. Thus, the system generates pure valley-polarized current
with maximum conductance. The chosen parameters of uniaxial strain and magnetic
field are in the range of experimental feasibility, which suggests that the
proposed scheme can be realized with current technology.


title:
Uniqueness of photon sphere for Einstein-Maxwell-dilaton black holes
  with arbitrary coupling constant

abstract:
  The uniqueness of static asymptotically flat photon sphere for static black
hole solution in Einstein-Maxwell-dilaton theory with arbitrary coupling
constant was proposed. Using the conformal positive energy theorem we show that
the dilaton sphere subject to the non-extremality condition authorizes a
cylinder over a topological sphere.


title:
A study of co-movements between oil price, stock index and exchange rate
  under a cross-bicorrelation perspective: the case of Mexico

abstract:
  In this chapter we studied the nonlinear co-movements between the Mexican
Crude Oil price, the Mexican Stock Market Index and the USD/MXN Exchange Rate,
for the sample period from 1994 to date. We used a battery of nonlinear tests,
cf. (Patterson & Ashley, 2000) and one multivariate test, in order to determine
the dynamic co-movement exerted from the oil prices to the stock and exchange
rate markets. Such co-movement and time windows are exposed using the Brooks &
Hinich (1999) cross- bicorrelation statistical test. The effects of oil spills
on other markets have been studied from different angles and on several
financial assets. In this study, we focus our attention on the detection, not
only of the correlations amongst markets but on the epochs in which such
nonlinear dependence might occur. This is important in order to understand
better, how the markets that drive the economy interact with each other. We
hope to contribute to the literature with such findings, filling a gap in the
emerging markets context, in particular, for the Mexican case.


title:
Spin-dependent Seebeck Effect in Aharonov-Bohm Rings with Rashba and
  Dresselhaus Spin-orbit Interactions

abstract:
  We theoretically investigate the spin-dependent Seebeck effect in an
Aharonov-Bohm mesoscopic ring in the presence of both Rashba and Dresselhaus
spin-orbit interactions under magnetic flux perpendicular to the ring. We apply
the Green's function method to calculate the spin Seebeck coefficient employing
the tight-binding Hamiltonian. It is found that the spin Seebeck coefficient is
proportional to the slope of the energy-dependent transmission coefficients. We
study the strong dependence of spin Seebeck coefficient on the Fermi energy,
magnetic flux, strength of spin-orbit coupling, and temperature. Maximum spin
Seebeck coefficients can be obtained when the strengths of Rashba and
Dresselhaus spin-orbit couplings are slightly different. The spin Seebeck
coefficient can be reduced by increasing temperature and disorder.


title:
YTrace: End-to-end Performance Diagnosis in Large Cloud and Content
  Providers

abstract:
  Content providers build serving stacks to deliver content to users. An
important goal of a content provider is to ensure good user experience, since
user experience has an impact on revenue. In this paper, we describe a system
at Yahoo called YTrace that diagnoses bad user experience in near real time. We
present the different components of YTrace for end-to-end multi-layer diagnosis
(instrumentation, methods and backend system), and the system architecture for
delivering diagnosis in near real time across all user sessions at Yahoo.
YTrace diagnoses problems across service and network layers in the end-to-end
path spanning user host, Internet, CDN and the datacenters, and has three
diagnosis goals: detection, localization and root cause analysis (including
cascading problems) of performance problems in user sessions with the cloud.
The key component of the methods in YTrace is capturing and discovering
causality, which we design based on a mix of instrumentation API, domain
knowledge and blackbox methods. We show three case studies from production that
span a large-scale distributed storage system, a datacenter-wide network, and
an end-to-end video serving stack at Yahoo. We end by listing a number of open
directions for performance diagnosis in cloud and content providers.


title: The reflection principle and Calder\'on problems with partial data

abstract:
  We solve the partial data Calder\'on problem for the connection Laplacian on
Riemann surfaces.


title:
Infinite Horizon Average Optimality of the N-network Queueing Model in
  the Halfin-Whitt Regime

abstract:
  We study the infinite horizon optimal control problem for N-network queueing
systems, which consist of two customer classes and two server pools, under
average (ergodic) criteria in the Halfin-Whitt regime. We consider three
control objectives: 1) minimizing the queueing (and idleness) cost, 2)
minimizing the queueing cost while imposing a constraint on idleness at each
server pool, and 3) minimizing the queueing cost while requiring fairness on
idleness. The running costs can be any nonnegative convex functions having at
most polynomial growth.
  For all three problems we establish asymptotic optimality, namely, the
convergence of the value functions of the diffusion-scaled state process to the
corresponding values of the controlled diffusion limit. We also present a
simple state-dependent priority scheduling policy under which the
diffusion-scaled state process is geometrically ergodic in the Halfin-Whitt
regime, and some results on convergence of mean empirical measures which
facilitate the proofs.


title: Microlocal resolvent estimates, revisited

abstract:
  Let $H$ be a Schr\"odinger type operator with long-range perturbation. We
study the wave front set of the distribution kernel of $(H-\lambda\mp
i0)^{-1}$, where $\lambda$ is in the absolutely continous spectrumof $H$.The
result is a refinement of the microlocal resolvent estimate of Isozaki-Kitada
\cite{IK1,IK2}. We prove the result for a class of pseudodifferential operators
on manifolds so that they apply to discrete Schr\"odinger operators and higher
order operators on the Euclidean space. The proof relies on propagation
estimates, whereas the original proof of Isozaki-Kitada relies on a
construction of parametrices.


title:
A Survey of Incentives and Mechanism Design for Human Computation
  Systems

abstract:
  Human computation systems (HCSs) have been widely adopted in various domains.
Their goal is to harness human intelligence to solve computational problems
that are beyond the capability of modern computers. One of the most challenging
problems in HCSs is how to incentivize a broad range of users to participate in
the system and make high efforts. This article surveys the field of HCSs from
the perspective of incentives and mechanism design. We first review
state-of-the-art HCSs, focusing on how incentives are provided to users. We
then use mechanism design to theoretically analyze different incentives. We
survey the mechanisms derived from state-of-the-art HCSs as well as classic
mechanisms that have been used in HCSs. Finally, we discuss eight promising
research directions for designing incentives in HCSs.


title: Re-acceleration Model for Radio Relics with Spectral Curvature

abstract:
  Most of the observed features of radio {\it gischt} relics such as spectral
steepening across the relic width and power-law-like integrated spectrum can be
adequately explained by diffusive shock acceleration (DSA) model, in which
relativistic electrons are (re-)accelerated at shock waves induced in the
intracluster medium. However, the steep spectral curvature in the integrated
spectrum above $\sim 2$ GHz detected in some radio relics such as the Sausage
relic in cluster CIZA J2242.8+5301 may not be interpreted by simple radiative
cooling of postshock electrons. In order to understand such steepening, we here
consider a model in which a spherical shock sweeps through and then exits out
of a finite-size cloud with fossil relativistic electrons. The ensuing
integrated radio spectrum is expected to steepen much more than predicted for
aging postshock electrons, since the re-acceleration stops after the
cloud-crossing time. Using DSA simulations that are intended to reproduce radio
observations of the Sausage relic, we show that both the integrated radio
spectrum and the surface brightness profile can be fitted reasonably well, if a
shock of speed, $u_s \sim 2.5-2.8\times 10^3 \kms$, and sonic Mach number, $M_s
\sim 2.7-3.0$, traverses a fossil cloud for $\sim 45$ Myr and the postshock
electrons cool further for another $\sim 10$ Myr. This attempt illustrates that
steep curved spectra of some radio gischt relics could be modeled by adjusting
the shape of the fossil electron spectrum and adopting the specific
configuration of the fossil cloud.


title: Multisections of piecewise linear manifolds

abstract:
  Recently Gay and Kirby described a new decomposition of smooth closed
$4$-manifolds called a trisection. This paper generalises Heegaard splittings
of $3$-manifolds and trisections of $4$-manifolds to all dimensions, using
triangulations as a key tool. In particular, we prove that every closed
piecewise linear $n$-manifold has a multisection, i.e. can be divided into
$k+1$ $n$-dimensional $1$-handlebodies, where $n=2k+1$ or $n=2k$, such that
intersections of the handlebodies have spines of small dimensions. Several
applications, constructions and generalisations of our approach are given.


title:
Formulating an $n$-person noncooperative game as a tensor
  complementarity problem

abstract:
  In this paper, we consider a class of $n$-person noncooperative games, where
the utility function of every player is given by a homogeneous polynomial
defined by the payoff tensor of that player, which is a natural extension of
the bimatrix game where the utility function of every player is given by a
quadratic form defined by the payoff matrix of that player. We will call such a
problem the multilinear game. We reformulate the multilinear game as a tensor
complementarity problem, a generalization of the linear complementarity
problem; and show that finding a Nash equilibrium point of the multilinear game
is equivalent to finding a solution of the resulted tensor complementarity
problem. Especially, we present an explicit relationship between the solutions
of the multilinear game and the tensor complementarity problem, which builds a
bridge between these two classes of problems. We also apply a smoothing-type
algorithm to solve the resulted tensor complementarity problem and give some
preliminary numerical results for solving the multilinear games.


title:
Magnetic Structure of the $S\,{=}\,1/2$ Quasi-Two-Dimensional
  Square-Lattice Heisenberg Antiferromagnet Sr$_2$CuTeO$_6$

abstract:
  The magnetic structure of the double perovskite compound Sr$_2$CuTeO$_6$ was
determined from neutron powder diffraction data. This material is magnetically
described as an $S\,{=}\,1/2$ quasi-two-dimensional square-lattice Heisenberg
model with antiferromagnetic nearest-neighbor and next-nearest-neighbor
interactions. Sr$_2$CuTeO$_6$ undergoes a magnetic phase transition at $T_{\rm
N}\,{\simeq}\,29\,$ K. The spin structure below $T_{\rm N}$ is N\'{e}el
antiferromagnetic on the square lattice, which means that the nearest-neighbor
interaction ($J_1$) is stronger than the next-nearest-neighbor interaction
($J_2$), in contrast to other isostructural compounds such as Ba$_2$CuWO$_6$
and Sr$_2$CuWO$_6$, for which $|J_1|\,{<}\,|J_2|$ is realized.


title: Superfluid behavior of quasi-1D p-H$_2$ inside carbon nanotube

abstract:
  We perform ab-initio Quantum Monte Carlo simulations of para-hydrogen
(pH$_2$) at $T=0$ K confined in carbon nanotubes (CNT) of different radii. The
radial density profiles show a strong layering of the pH$_2$ molecules which
grow, with increasing number of molecules, in solid concentric cylindrical
shells and eventually a central column. The central column can be considered an
effective one-dimensional (1D) fluid whose properties are well captured by the
Tomonaga-Luttinger liquid theory. The Luttinger parameter is explicitly
computed and interestingly it shows a non-monotonic behavior with the linear
density similar to what found for pure 1D $^3$He. Remarkably, for the central
column in a (10,10) CNT, we found an ample linear density range in which the
Luttinger liquid is (i) superfluid and (ii) stable against a weak disordered
external potential, as the one expected inside realistic pores. This superfluid
behavior could be experimentally revealed in bundles of carbon nanotubes, where
deviations from classical inertial values associated with superfluid density
could be measured via torsional oscillator techniques. In summary, our results
suggest that pH$_2$ within carbon nanopores could be a practical realization of
the long sought-after, elusive superfluid phase of parahydrogen.


title:
Performance Analysis of $l_0$ Norm Constrained Recursive Least Squares
  Algorithm

abstract:
  Performance analysis of $l_0$ norm constrained Recursive least Squares (RLS)
algorithm is attempted in this paper. Though the performance pretty attractive
compared to its various alternatives, no thorough study of theoretical analysis
has been performed. Like the popular $l_0$ Least Mean Squares (LMS) algorithm,
in $l_0$ RLS, a $l_0$ norm penalty is added to provide zero tap attractions on
the instantaneous filter taps. A thorough theoretical performance analysis has
been conducted in this paper with white Gaussian input data under assumptions
suitable for many practical scenarios. An expression for steady state MSD is
derived and analyzed for variations of different sets of predefined variables.
Also a Taylor series expansion based approximate linear evolution of the
instantaneous MSD has been performed. Finally numerical simulations are carried
out to corroborate the theoretical analysis and are shown to match well for a
wide range of parameters.


title:
Landau-Zener-Stuckelberg-Majorana interference in a 3D transmon driven
  by a chirped microwave

abstract:
  By driving a 3D transmon with microwave fields, we generate an effective
avoided energy-level crossing. Then we chirp microwave frequency, which is
equivalent to driving the system through the avoided energy-level crossing by
sweeping the avoided crossing. A double-passage chirp produces
Landau-Zener-St\"uckelberg-Majorana interference that agree well with the
numerical results. Our method is fully applicable to other quantum systems that
contain no intrinsic avoided level crossing, providing an alternative approach
for quantum control and quantum simulation.


title:
Temperature dependence of the threshold magnetic field for nucleation
  and domain wall propagation in an inhomogeneous structure with grain boundary

abstract:
  In order to study the dependence of the coercive force of sintered magnets on
temperature, nucleation and domain wall propagation at the grain boundary are
studied as rate-determining processes of the magnetization reversal phenomena
in magnets consisting of bulk hard magnetic grains contacting via grain
boundaries of a soft magnetic material. These systems have been studied
analytically for a continuum model at zero temperature (A. Sakuma, et al. J.
Mag. Mag. Mat. {\bf 84} 52 (1990)). In the present study, the temperature
dependence is studied by making use of the stochastic Landau-Lifshitz-Gilbert
equation at finite temperatures. In particular, the threshold fields for
nucleation and domain wall propagation are obtained as functions of ratios of
magnetic interactions and anisotropies of the soft and hard magnets for various
temperatures. It was found that the threshold field for domain wall propagation
is robust against thermal fluctuations, while that for nucleation is fragile.
The microscopic mechanisms of the observed temperature dependence are
discussed.


title: Rare Top Decays in Minimal and Non-minimal Universal Extra Dimension

abstract:
  The flavour changing decays of the top quark are severely suppressed in the
Standard Model by virtue of the Glashow-Iliopoulos-Maiani mechanism. Many
beyond Standard Model extensions predict the decay rates at a level that is
observable in the LHC. We perform a complete one-loop calculation of the
flavour changing top quark decays $t\to c\gamma$ and $t\to ch$ in the universal
extra dimensional model. Apart from considering the decay rates in the minimal
version of the model, we also calculate the rates in the non-minimal scenario
where the presence of boundary localised terms interestingly modify the set-up.
We find that the decay rates in the minimal variant of the model do not change
much from their Standard Model values. In the non-minimal version of this
model, these decay rates can be higher for specific choices of the boundary
localised parameters for a certain range of inverse compactification radius.
But these model parameters lead to Kaluza-Klein particle masses that are in
tension with various searches at the LHC.


title:
On the autonomous norm on the group of Hamiltonian diffeomorphisms of
  the torus

abstract:
  We prove that the autonomous norm on the group of Hamiltonian diffeomorphisms
of the two-dimensional torus is unbounded. We provide explicit examples of
Hamiltonian diffeomorphisms with arbitrarily large autonomous norm. For the
proofs we construct quasimorphisms on $Ham(T^2)$ and some of them are Calabi.


title:
Ab initio Study of Cross-Interface Electron-Phonon Couplings in FeSe
  Thin Films on SrTiO$_3$ and BaTiO$_3$

abstract:
  We study the electron-phonon coupling strength near the interface of
monolayer and bilayer FeSe thin films on SrTiO$_3$, BaTiO$_3$, and
oxygen-vacant SrTiO$_3$ substrates, using ab initio methods. The calculated
total electron-phonon coupling strength $\lambda=0.2\text{--}0.3$ cannot
account for the high $T_c\sim 70$ K observed in these systems through the
conventional phonon-mediated pairing mechanism. In all of these systems,
however, we find that the coupling constant of a polar oxygen branch peaks at
$\mathbf{q}=0$ with negligible coupling elsewhere, while the energy of this
mode coincides with the offset energy of the replica bands measured recently by
angle-resolved photoemission spectroscopy experiments. But the integrated
coupling strength for this mode from our current calculations is still too
small to produce the observed high $T_c$, even through the more efficient
pairing mechanism provided by the forward scattering. We arrive at the same
qualitative conclusion when considering a checkerboard antiferromagnetic
configuration in the Fe layer. In light of the experimental observations of the
replica band feature and the relatively high $T_c$ of FeSe monolayers on polar
substrates, our results point towards a cooperative role for the
electron-phonon interaction, where the cross-interface interaction acts in
conjunction with a purely electronic interaction. We also discuss a few
scenarios where the coupling strength obtained here may be enhanced.


title:
The Gaia-ESO Survey: Sodium and aluminium abundances in giants and
  dwarfs - Implications for stellar and Galactic chemical evolution

abstract:
  Stellar evolution models predict that internal mixing should cause some
sodium overabundance at the surface of red giants more massive than ~ 1.5--2.0
Msun. The surface aluminium abundance should not be affected. Nevertheless,
observational results disagree about the presence and/or the degree of the Na
and Al overabundances. In addition, Galactic chemical evolution models adopting
different stellar yields lead to quite different predictions for the behavior
of [Na/Fe] and [Al/Fe] versus [Fe/H]. Overall, the observed trends of these
abundances with metallicity are not well reproduced. We readdress both issues,
using new Na and Al abundances determined within the Gaia-ESO Survey, using two
samples: i) more than 600 dwarfs of the solar neighborhood and of open clusters
and ii) low- and intermediate-mass clump giants in six open clusters.
Abundances of Na in giants with mass below ~2.0 Msun, and of Al in giants below
~3.0 Msun, seem to be unaffected by internal mixing processes. For more massive
giants, the Na overabundance increases with stellar mass. This trend agrees
well with predictions of stellar evolutionary models. Chemical evolution models
that are able to fit well the observed [Na/Fe] vs. [Fe/H] trend in solar
neighborhood dwarfs can not simultaneously explain the run of [Al/Fe] with
[Fe/H], and viceversa. The comparison with stellar ages is hampered by severe
uncertainties. Indeed, reliable age estimates are available for only a half of
the stars of the sample. We conclude that Al is underproduced by the models,
except for stellar ages younger than about 7 Gyr. In addition, some significant
source of late Na production seems to be missing in the models. Either current
Na and Al yields are affected by large uncertainties, and/or some important
Galactic source(s) of these elements has not been taken into account up to now.
[abridged]


title: Gravitational effects on the Higgs field within the Solar System

abstract:
  The Higgs mechanism predicts, apart from the existence of a new scalar boson,
the presence of a constant Higgs field that permeates all of space. The vacuum
expectation value (VEV) of this field is affected by quantum corrections which
are mainly generated by the self-interactions and couplings of the Higgs field
to gauge bosons and heavy quarks. In this work we show that gravity can affect,
in a non-trivial way, these quantum corrections through the finite parts of the
one-loop contributions to the effective potential. In particular, we consider
the corrections generated by the Standard Model Higgs self-interactions in
slowly-varying weak gravitational backgrounds. The obtained results amount to
the existence of non-negligible inhomogeneities in the Higgs VEV. Such
inhomogeneities translate into spatial variations of the particle masses, and
in particular of the proton-to-electron mass ratio. We find that these Higgs
perturbations in our Solar System are controlled by the Eddington parameter,
and are absent in pure General Relativity. Yet, they may be present in modified
gravity theories. This predicted effect may be constrained by atomic clocks or
high-resolution spectroscopic measurements, which could allow to improve
current limits on modifications of Einstein's gravity.


title:
Feature Based Task Recommendation in Crowdsourcing with Implicit
  Observations

abstract:
  Existing research in crowdsourcing has investigated how to recommend tasks to
workers based on which task the workers have already completed, referred to as
{\em implicit feedback}. We, on the other hand, investigate the task
recommendation problem, where we leverage both implicit feedback and explicit
features of the task. We assume that we are given a set of workers, a set of
tasks, interactions (such as the number of times a worker has completed a
particular task), and the presence of explicit features of each task (such as,
task location). We intend to recommend tasks to the workers by exploiting the
implicit interactions, and the presence or absence of explicit features in the
tasks. We formalize the problem as an optimization problem, propose two
alternative problem formulations and respective solutions that exploit implicit
feedback, explicit features, as well as similarity between the tasks. We
compare the efficacy of our proposed solutions against multiple
state-of-the-art techniques using two large scale real world datasets.


title: Simplifications of the Keiper/Li approach to the Riemann Hypothesis

abstract:
  The Keiper/Li constants $\{\lambda_n\}_{n=1,2,\ldots}$ are asymptotically ($n
\to \infty$) sensitive to the Riemann Hypothesis, but highly elusive
analytically and difficult to compute numerically. We present quite explicit
variant sequences that stay within the abstract Keiper--Li frame, and appear
simpler to analyze and compute.


title:
Existence and regularity of source-type self-similar solutions for
  stable thin-film equations

abstract:
  We investigate the existence and the boundary regularity of source-type
self-similar solutions to the thin-film equation
$h_t=-(h^nh_{zzz})_z+(h^{n+3})_{zz},$ $ t>0,\; z\in \mathbb{R};\; h(0,z)=
\omega \delta(z)$ where $n\in (\frac{3}{2},3),\; \omega > 0$ and $\delta$ is
the Dirac mass at the origin. It is known that the leading order expansion near
the edge of the support coincides with that of a traveling-wave solution for
the standard thin-film equation: $h_t=-(h^nh_{zzz})_z$. In this paper we
sharpen this result, proving that the higher order corrections are analytic
with respect to three variables: the first one is just the {spatial} variable,
whereas the second and the third (except for $n = 2$) are irrational powers of
it. It is known that this third variable does not appear for the thin-film
equation without gravity.


title:
Optical diffraction tomography using a digital micromirror device for
  stable measurements of 4-D refractive index tomography of cells

abstract:
  Optical diffraction tomography (ODT) is an interferometric microscopy
technique capable of measuring 3-D refractive index (RI) distribution of
transparent samples. Multiple 2-D holograms of a sample illuminated with
various angles are measured, from which 3-D RI map of the sample is
reconstructed via the diffraction theory. ODT has been proved as a powerful
tool for the study of biological cells, due to its non-invasiveness, label-free
and quantitative imaging capability. Recently, our group has demonstrated that
a digital micromirror device (DMD) can be exploited for fast and precise
control of illumination beams for ODT. In this work, we systematically study
the precision and stability of the ODT system equipped with a DMD and present
measurements of 3-D and 4-D RI maps of various types of live cells including
human red blood cells, white blood cells, hepatocytes, and HeLa cells.
Furthermore, we also demonstrate the effective visualization of 3-D RI maps of
live cells utilizing the measured information about the values and gradient of
RI tomograms.


title:
SWKB and proper quantization conditions for translationally shape
  invariant potentials

abstract:
  Using a recently proposed classification for the primary translationally
shape invariant potentials, we show that the exact quantization rule formulated
by Ma and Xu is equivalent to the supersymmetric JWKB quantization condition.
The energy levels for the two considered categories of shaped invariant
potentials are also derived.


title: Spectroscopy of $^{35}$P using the one-proton knockout reaction

abstract:
  The structure of $^{35}$P was studied with a one-proton knockout reaction
at88~MeV/u from a $^{36}$S projectile beam at NSCL. The $\gamma$ rays from
thedepopulation of excited states in $^{35}$P were detected with GRETINA,
whilethe $^{35}$P nuclei were identified event-by-event in the focal plane of
theS800 spectrograph. The level scheme of $^{35}$P was deduced up to 7.5 MeV
using$\gamma-\gamma$ coincidences. The observed levels were attributed to
protonremovals from the $sd$-shell and also from the deeply-bound $p\_{1/2}$
orbital.The orbital angular momentum of each state was derived from the
comparisonbetween experimental and calculated shapes of individual
($\gamma$-gated)parallel momentum distributions. Despite the use of different
reactions andtheir associate models, spectroscopic factors, $C^2S$, derived
from the$^{36}$S $(-1p)$ knockout reaction agree with those obtained earlier
from$^{36}$S($d$,\nuc{3}{He}) transfer, if a reduction factor $R\_s$, as
deducedfrom inclusive one-nucleon removal cross sections, is applied to the
knockout transitions.In addition to the expected proton-hole configurations,
other states were observedwith individual cross sections of the order of
0.5~mb. Based on their shiftedparallel momentum distributions, their decay
modes to negative parity states,their high excitation energy (around 4.7~MeV)
and the fact that they were notobserved in the ($d$,\nuc{3}{He}) reaction, we
propose that they may resultfrom a two-step mechanism or a nucleon-exchange
reaction with subsequent neutronevaporation. Regardless of the mechanism, that
could not yet be clarified, thesestates likely correspond to neutron core
excitations in \nuc{35}{P}. Thisnewly-identified pathway, although weak, offers
the possibility to selectivelypopulate certain intruder configurations that are
otherwise hard to produceand identify.


title: On the Concavity of Auxiliary Function in Classical-Quantum Channels

abstract:
  The auxiliary function of a classical channel appears in two fundamental
quantities that upper and lower bound the error probability, respectively. A
crucial property of the auxiliary function is its concavity, which leads to
several important results in finite block length analysis. In this paper, we
prove that the auxiliary function of a classical-quantum channel also enjoys
the same concave property, extending an earlier partial result to its full
generality. The key component in our proof is a beautiful result of geometric
means of operators.


title: Isoclinic Lie Crossed Modules

abstract:
  We introduce the notion of isoclinism among crossed modules of Lie algebras,
which will be called "Lie crossed modules" hereafter, and investigate some
basic properties. Additionally, we introduce the notion of class preserving
actor of a Lie crossed module and the relation with isoclinism.


title:
Refinement on non-hydrostatic shallow granular flow model in a global
  Cartesian coordinate system

abstract:
  Current shallow granular flow models suited to arbitrary topography can be
divided into two types, those formulated in bed-fitted curvilinear coordinates,
and those formulated in global Cartesian coordinates. The shallow granular flow
model of Denlinger and Iverson \cite{Denlinger2004} and the Boussinesq-type
shallow granular flow theory of Castro-Orgaz \emph{et al}. \cite{Castro2014}
are formulated in a Cartesian coordinate system (with $z$ vertical), and both
account for the effect of nonzero vertical acceleration on depth-averaged
momentum fluxes and stress states. In this paper, we first reformulate the
vertical normal stress of Castro-Orgaz \emph{et al}. \cite{Castro2014} in a
quadratic polynomial in the relative elevation $\eta$. This form allows for
analytical depth integration of the vertical normal stress. We then calculate
the basal normal stress based on the basal friction law and scaling analysis.
These calculations, plus certain constitutive relations, lead to a refined full
non-hydrostatic shallow granular flow model, which is further rewritten in a
form of Boussinesq-type water wave equations for future numerical studies. In
the present numerical study, we apply the open-source code TITAN2D to numerical
solution of a low-order version of the full model involving only a mean
vertical acceleration correction term. To cure the numerical instability
associated with discretization of the enhanced gravity, we propose an
approximate formula for the enhanced gravity by utilizing the hydrostatic
pressure assumption in the bed normal direction. Numerical calculations are
conducted for several test cases involving steep slopes. Comparison with a
bed-fitted model shows that even the simplified non-hydrostatic Cartesian model
can be used to simulate shallow granular flows over arbitrary topography.


title:
Asymptotics for singular solutions of quasilinear elliptic equations
  with absorption term

abstract:
  We are concerned with the asymptotic analysis of positive blow-up boundary
solutions for a class of quasilinear elliptic equations with absorption term.
By means of the Karamata theory we establish the first two terms in the
expansion of the singular solution near the boundary. Our analysis includes
large classes of nonlinearities of Keller-Osserman type.


title:
Stationary waves of Schr\"{o}dinger-type equations with variable
  exponent

abstract:
  We are concerned with a class of nonlinear Schr\"{o}dinger-type equations
with a reaction term and a differential operator that involves a variable
exponent. By using related variational methods, we establish several existence
results.


title: Distinguishing number and distinguishing index of certain graphs

abstract:
  The distinguishing number (index) $D(G)$ ($D'(G)$) of a graph $G$ is the
least integer $d$ such that $G$ has an vertex labeling (edge labeling) with $d$
labels that is preserved only by a trivial automorphism. In this paper we
compute these two parameters for some specific graphs. Also we study the
distinguishing number and the distinguishing index of corona product of two
graphs.


title: Asymptotically Optimal Gathering on a Grid

abstract:
  In this paper, we solve the local gathering problem of a swarm of $n$
indistinguishable, point-shaped robots on a two dimensional grid in
asymptotically optimal time $\mathcal{O}(n)$ in the fully synchronous
$\mathcal{FSYNC}$ time model. Given an arbitrarily distributed (yet connected)
swarm of robots, the gathering problem on the grid is to locate all robots
within a $2\times 2$-sized area that is not known beforehand. Two robots are
connected if they are vertical or horizontal neighbors on the grid. The
locality constraint means that no global control, no compass, no global
communication and only local vision is available; hence, a robot can only see
its grid neighbors up to a constant $L_1$-distance, which also limits its
movements. A robot can move to one of its eight neighboring grid cells and if
two or more robots move to the same location they are \emph{merged} to be only
one robot. The locality constraint is the significant challenging issue here,
since robot movements must not harm the (only globally checkable) swarm
connectivity. For solving the gathering problem, we provide a synchronous
algorithm -- executed by every robot -- which ensures that robots merge without
breaking the swarm connectivity. In our model, robots can obtain a special
state, which marks such a robot to be performing specific connectivity
preserving movements in order to allow later merge operations of the swarm.
Compared to the grid, for gathering in the Euclidean plane for the same robot
and time model the best known upper bound is $\mathcal{O}(n^2)$.


title:
Partition functions and equilibrium constants for diatomic molecules and
  atoms of astrophysical interest

abstract:
  Partition functions and dissociation equilibrium constants are presented for
291 diatomic molecules for temperatures in the range from near absolute zero to
10000 K, thus providing data for many diatomic molecules of astrophysical
interest at low temperature. The calculations are based on molecular
spectroscopic data from the book of Huber and Herzberg with significant
improvements from the literature, especially updated data for ground states of
many of the most important molecules by Irikura. Dissociation energies are
collated from compilations of experimental and theoretical values. Partition
functions for 284 species of atoms for all elements from H to U are also
presented based on data collected at NIST. The calculated data are expected to
be useful for modelling a range of low density astrophysical environments,
especially star-forming regions, protoplanetary disks, the interstellar medium,
and planetary and cool stellar atmospheres. The input data, which will be made
available electronically, also provides a possible foundation for future
improvement by the community.


title:
Coverage and capacity scaling laws in downlink ultra-dense cellular
  networks

abstract:
  Driven by new types of wireless devices and the proliferation of
bandwidth-intensive applications, data traffic and the corresponding network
load are increasing dramatically. Network densification has been recognized as
a promising and efficient way to provide higher network capacity and enhanced
coverage. Most prior work on performance analysis of ultra-dense networks
(UDNs) has focused on random spatial deployment with idealized singular path
loss models and Rayleigh fading. In this paper, we consider a more precise and
general model, which incorporates multi-slope path loss and general fading
distributions. We derive the tail behavior and scaling laws for the coverage
probability and the capacity considering strongest base station association in
a Poisson field network. Our analytical results identify the regimes in which
the signal-to-interference-plus-noise ratio (SINR) either asymptotically grows,
saturates, or decreases with increasing network density. We establish general
results on when UDNs lead to worse or even zero SINR coverage and capacity, and
we provide crisp insights on the fundamental limits of wireless network
densification.


title:
Chemical spots on the surface of the strongly magnetic Herbig Ae star HD
  101412

abstract:
  Due to the knowledge of the rotation period and the presence of a rather
strong surface magnetic field, the sharp-lined young Herbig Ae star HD 101412
with a rotation period of 42 d has become one of the most well-studied targets
among the Herbig Ae stars. High-resolution HARPS polarimetric spectra of HD
101412 were recently obtained on seven different epochs. Our study of the
spectral variability over the part of the rotation cycle covered by HARPS
observations reveals that the line profiles of the elements Mg, Si, Ca, Ti, Cr,
Mn, Fe, and Sr are clearly variable while He exhibits variability that is
opposite to the behaviour of the other elements studied. Since classical Ap
stars usually show a relationship between the magnetic field geometry and the
distribution of element spots, we used in our magnetic field measurements
different line samples belonging to the three elements with the most numerous
spectral lines, Ti, Cr, and Fe. Over the time interval covered by the available
spectra, the longitudinal magnetic field changes sign from negative to positive
polarity. The distribution of field values obtained using Ti, Cr, and Fe lines
is, however, completely different compared to the magnetic field values
determined in previous low-resolution FORS 2 measurements, where hydrogen
Balmer lines are the main contributors to the magnetic field measurements,
indicating the presence of concentration of the studied iron-peak elements in
the region of the magnetic equator. Further, we discuss the potential role of
contamination by the surrounding warm circumstellar matter in the appearance of
Zeeman features obtained using Ti lines.


title: Some matrix nearness problems suggested by Tikhonov regularization

abstract:
  The numerical solution of linear discrete ill-posed problems typically
requires regularization, i.e., replacement of the available ill-conditioned
problem by a nearby better conditioned one. The most popular regularization
methods for problems of small to moderate size are Tikhonov regularization and
truncated singular value decomposition (TSVD). By considering matrix nearness
problems related to Tikhonov regularization, several novel regularization
methods are derived. These methods share properties with both Tikhonov
regularization and TSVD, and can give approximate solutions of higher quality
than either one of these methods.


title: Gabor Wavelets in Image Processing

abstract:
  This work shows the use of a two-dimensional Gabor wavelets in image
processing. Convolution with such a two-dimensional wavelet can be separated
into two series of one-dimensional ones. The key idea of this work is to
utilize a Gabor wavelet as a multiscale partial differential operator of a
given order. Gabor wavelets are used here to detect edges, corners and blobs. A
performance of such an interest point detector is compared to detectors
utilizing a Haar wavelet and a derivative of a Gaussian function. The proposed
approach may be useful when a fast implementation of the Gabor transform is
available or when the transform is already precomputed.


title:
Singular $F(R)$ Cosmology Unifying Early and Late-time Acceleration with
  Matter and Radiation Domination Era

abstract:
  We present some cosmological models which unify the late and early-time
acceleration eras with the radiation and the matter domination era, and we
realize the cosmological models by using the theoretical framework of $F(R)$
gravity. Particularly, the first model unifies the late and early-time
acceleration with the matter domination era, and the second model unifies all
the evolution eras of our Universe. The two models are described in the same
way at early and late times, and only the intermediate stages of the evolution
have some differences. Each cosmological model contains two Type IV
singularities which are chosen to occur one at the end of the inflationary era
and one at the end of the matter domination era. The cosmological models at
early times are approximately identical to the $R^2$ inflation model, so these
describe a slow-roll inflationary era which ends when the slow-roll parameters
become of order one. The inflationary era is followed by the radiation era and
after that the matter domination era follows, which lasts until the second Type
IV singularity, and then the late-time acceleration era follows. The models
produce a nearly scale invariant power spectrum of primordial curvature
perturbations and a scalar-to-tensor ratio which are compatible with the most
recent observational data and it seems that the deceleration acceleration
transition is crucially affected by the presence of the second Type IV
singularity which occurs at the end of the matter domination era. We perform an
analysis of the Hubble horizon evolution, and in addition, we investigate which
$F(R)$ gravity can successfully realize each of the four cosmological epochs.


title:
Oxygen vacancy induced room temperature metal-insulator transition in
  nickelates films and its potential application in photovoltaics

abstract:
  Oxygen vacancy is intrinsically coupled with magnetic, electronic and
transport properties of transition-metal oxide materials and directly
determines their multifunctionality. Here, we demonstrate reversible control of
oxygen content by post-annealing at temperature lower than 300 degree
centigrade and realize the reversible metal-insulator transition in epitaxial
NdNiO3 films. Importantly, over six orders of magnitude in the resistance
modulation and a large change in optical band gap are demonstrated at room
temperature without destroying the parent framework and changing the p-type
conductive mechanism. Further study revealed that oxygen vacancies stabilized
the insulating phase at room temperature is universal for perovskite nickelates
films. Acting as electron donors, oxygen vacancies not only stabilize the
insulating phase at room temperature, but also induce a large magnetization of
~50 emu/cm3 due to the formation of strongly correlated Ni2+ t2g6eg2 states.
The band gap opening is an order of magnitude larger than that of the thermally
driven metal-insulator transition and continuously tunable. Potential
application of the newly found insulating phase in photovoltaics has been
demonstrated in the nickelates-based heterojunctions. Our discovery opens up
new possibilities for strongly correlated perovskite nickelates.


title: Efficient weight vectors from pairwise comparison matrices

abstract:
  Pairwise comparison matrices are frequently applied in multi-criteria
decision making. A weight vector is called efficient if no other weight vector
is at least as good in approximating the elements of the pairwise comparison
matrix, and strictly better in at least one position. A weight vector is weakly
efficient if the pairwise ratios cannot be improved in all non-diagonal
positions. We show that the principal eigenvector is always weakly efficient,
but numerical examples show that it can be inefficient. The linear programs
proposed test whether a given weight vector is (weakly) efficient, and in case
of (strong) inefficiency, an efficient (strongly) dominating weight vector is
calculated. The proposed algorithms are implemented in Pairwise Comparison
Matrix Calculator, available at pcmc.online.


title: The category of $\mathbb{Z}_2^n$-supermanifolds

abstract:
  In Physics and in Mathematics $\mathbb{Z}_2^n$-gradings, $n>1$, appear in
various fields. The corresponding sign rule is determined by the `scalar
product' of the involved $\mathbb{Z}_2^n$-degrees. The
$\mathbb{Z}_2^n$-Supergeometry exhibits challenging differences with the
classical one: nonzero degree even coordinates are not nilpotent, and even
(resp., odd) coordinates do not necessarily commute (resp., anticommute)
pairwise. In this article we develop the foundations of the theory: we define
$\mathbb{Z}_2^n$-supermanifolds and provide examples in the ringed space and
coordinate settings. We thus show that formal series are the appropriate
substitute for nilpotency. Moreover, the class of
$\mathbb{Z}_2^\bullet$-supermanifolds is closed with respect to the tangent and
cotangent functors. We explain that any $n$-fold vector bundle has a canonical
`superization' to a $\mathbb{Z}_2^n$-supermanifold and prove that the
fundamental theorem describing supermorphisms in terms of coordinates can be
extended to the $\mathbb{Z}_2^n$-context.


title: A Remark on Channels with Transceiver Distortion

abstract:
  Information transmission over channels with transceiver distortion is
investigated via generalized mutual information (GMI) under Gaussian input
distribution and nearest-neighbor decoding. A canonical transceiver structure
in which the channel output is processed by a minimum mean-squared error
estimator before decoding is established to maximize the GMI, and the
well-known Bussgang's decomposition is shown to be a heuristic that is
consistent with the GMI under linear output processing.


title: Replicated Entanglement Entropy

abstract:
  We introduce "Replicated Entanglement Entropy (REE)" as the entanglement
entropy of a subspace in a replicated theory. We calculate this quantity by
replicating the original theory in two steps along the same entangling region
and taking the proper limit on the second replica number. The quantity has a
clear physical meaning, a thermodynamic interpretation and a holographic dual.


title: Long-range hydrodynamic effect due to a single vesicle in linear flow

abstract:
  Vesicles are involved in a vast variety of transport processes in living
organisms. Additionally, they serve as a model for the dynamics of cell
suspensions. Predicting the rheological properties of their suspensions is
still an open question, as even the interaction of pairs is yet to be fully
understood. Here we analyse the effect of a single vesicle, undergoing
tank-treading motion, on its surrounding shear flow by studying the induced
disturbance field $\delta \vec{V}$, the difference between the velocity field
in its presence and absence. The comparison between experiments and numerical
simulations reveals an impressive agreement. Tracking ridges in the disturbance
field magnitude landscape, we identify the principal directions along which the
velocity difference field is analysed in the vesicle vicinity. The disturbance
magnitude is found to be significant up to about 4 vesicles radii and can be
described by a power law decay with the distance $d$ from the vesicle $ \|
\delta \vec{V} \| \propto d^{-3/2}$. This is consistent with previous
experimental results on the separation distance between two interacting
vesicles under similar conditions, for which their dynamics is altered. This is
an indication of vesicles long-range effect via the disturbance field and calls
for the proper incorporation of long-range hydrodynamic interactions when
attempting to derive rheological properties of vesicle suspensions.


title: Safety in Numbers: Anonymization Makes Centralized Systems Trustworthy

abstract:
  Decentralized systems can be more resistant to operator mischief than
centralized ones, but they are substantially harder to develop, deploy, and
maintain. This cost is dramatically reduced if the decentralized part of the
system can be made highly generic, and thus incorporated into many different
applications. We show how existing anonymization systems can serve this
purpose, securing a public database against equivocation by its operator
without the need for cooperation by the database owner. We derive bounds on the
probability of successful equivocation, and in doing so, we demonstrate that
anonymization systems are not only important for user privacy, but that by
providing privacy to machines they have a wider value within the internet
infrastructure


title: Cylindrically Polarized Nondiffracting Optical Pulses

abstract:
  We extend the concept of radially and azimuthally polarized optical beams to
the polychromatic domain by introducing cylindrically polarized nondiffracting
optical pulses. In particular, we discuss in detail the case of cylindrically
polarized X-waves, both in the paraxial and nonparaxial regime. The explicit
expressions for the electric and magnetic fields of cylindrically polarized
X-waves is also reported.


title: Regularization matrices determined by matrix nearness problems

abstract:
  This paper is concerned with the solution of large-scale linear discrete
ill-posed problems with error-contaminated data. Tikhonov regularization is a
popular approach to determine meaningful approximate solutions of such
problems. The choice of regularization matrix in Tikhonov regularization may
significantly affect the quality of the computed approximate solution. This
matrix should be chosen to promote the recovery of known important features of
the desired solution, such as smoothness and monotonicity. We describe a novel
approach to determine regularization matrices with desired properties by
solving a matrix nearness problem. The constructed regularization matrix is the
closest matrix in the Frobenius norm with a prescribed null space to a given
matrix. Numerical examples illustrate the performance of the regularization
matrices so obtained.


title:
The inverse thermal spin-orbit torque and the relation of the
  Dzyaloshinskii-Moriya interaction to ground-state energy currents

abstract:
  Using the Kubo linear-response formalism we derive expressions to calculate
the heat current generated by magnetization dynamics in magnets with broken
inversion symmetry and spin-orbit interaction (SOI). The effect of producing
heat currents by magnetization dynamics constitutes the Onsager reciprocal of
the thermal spin-orbit torque (TSOT), i.e., the generation of torques on the
magnetization due to temperature gradients. We find that the energy current
driven by magnetization dynamics contains a contribution from the
Dzyaloshinskii-Moriya interaction (DMI), which needs to be subtracted from the
Kubo linear response of the energy current in order to extract the heat
current. We show that the expressions of the DMI coefficient can be derived
elegantly from the DMI energy current. Guided by formal analogies between the
Berry phase theory of DMI on the one hand and the modern theory of orbital
magnetization on the other hand we are led to an interpretation of the latter
in terms of energy currents as well. Based on \textit{ab-initio} calculations
we investigate the heat current driven by magnetization dynamics in Mn/W(001)
magnetic bilayers. We predict that fast domain walls drive strong ITSOT heat
currents.


title: Graph Wavelets via Sparse Cuts: Extended Version

abstract:
  Modeling information that resides on vertices of large graphs is a key
problem in several real-life applications, ranging from social networks to the
Internet-of-things. Signal Processing on Graphs and, in particular, graph
wavelets can exploit the intrinsic smoothness of these datasets in order to
represent them in a both compact and accurate manner. However, how to discover
wavelet bases that capture the geometry of the data with respect to the signal
as well as the graph structure remains an open question. In this paper, we
study the problem of computing graph wavelet bases via sparse cuts in order to
produce low-dimensional encodings of data-driven bases. This problem is
connected to known hard problems in graph theory (e.g. multiway cuts) and thus
requires an efficient heuristic. We formulate the basis discovery task as a
relaxation of a vector optimization problem, which leads to an elegant solution
as a regularized eigenvalue computation. Moreover, we propose several
strategies in order to scale our algorithm to large graphs. Experimental
results show that the proposed algorithm can effectively encode both the graph
structure and signal, producing compressed and accurate representations for
vertex values in a wide range of datasets (e.g. sensor and gene networks) and
significantly outperforming the best baseline.


title: Optomechanical interactions in non-Hermitian photonic molecules

abstract:
  We study optomechanical interactions in non-Hermitian photonic molecules that
support two photonic states and one acoustic mode. The nonlinear steady-state
solutions and their linear stability landscapes are investigated as a function
of the system's parameters and excitation power levels. We also examine the
temporal evolution of the system and uncover different regimes of nonlinear
dynamics. Our analysis reveals several important results: (1) Parity-time
($\mathcal{PT}$) symmetry is not necessarily the optimum choice for maximum
optomechanical interaction. (2) Stable steady-state solutions are not always
reached under continuous wave (CW) optical excitations. (3) Accounting for gain
saturation effects can regulate the behavior of the otherwise unbounded
oscillation amplitudes. Our study provides a deeper insight into the interplay
between optical non-Hermiticity and optomechanical coupling and can thus pave
the way for new device applications.


title:
Optical humidity sensor based on a liquid whispering-gallery mode
  resonator

abstract:
  We experimentally demonstrate the use of a novel liquid state,
whispering-gallery-mode optical resonator as a highly sensitive humidity
sensor. The optical resonator used consists of a droplet made of glycerol, a
transparent liquid that enables high optical quality factor, doped with
rhodamine 6G, which acts as fluorescent emitter. As glycerol is highly
hygroscopic, the refractive index and radius of the droplet change with ambient
humidity. This produces a shift on the whispering gallery modes wavelengths,
which modulates the emission of rhodamine 6G. This easily-made device has an
unpreceded sensitivity of 10-3 per relative humidity percent.


title:
Boundary behaviour of Dirichlet series with applications to universal
  series

abstract:
  This paper establishes connections between the boundary behaviour of
functions representable as absolutely convergent Dirichlet series in a
half-plane and the convergence properties of partial sums of the Dirichlet
series on the boundary. This yields insights into the boundary behaviour of
Dirichlet series and Taylor series which have universal approximation
properties.


title:
Activation cross-sections of proton induced reactions on $^{nat}$Sm up
  to 65 MeV

abstract:
  Activation cross sections for proton induced reactions on Sm are presented
for the first time for
$^{nat}$Sm(p,xn)$^{154,152m2,152m1,152g,150m,150g,149,148,147,146,145}$Eu,
$^{nat}$Sm(p,x)$^{153,145}$Sm,
$^{nat}$Sm(p,x)$^{151,150,149,148g,148m,146,144,143}$Pm and
$^{nat}$Sm(p,x)$^{141}$Nd up to 65 MeV. The cross sections were measured via
activation method by using a stacked-foil irradiation technique and high
resolution gamma ray spectroscopy. The results were compared with results of
the nuclear reaction codes ALICE, EMPIRE and TALYS (results taken from TENDL
libraries). Integral yields of the activation products were calculated from the
excitation functions.


title: Multi-dimensional structure of accreting young stars

abstract:
  This work is the first attempt to describe the multi-dimensional structure of
accreting young stars based on fully compressible time implicit
multi-dimensional hydrodynamics simulations. One major motivation is to analyse
the validity of accretion treatment used in previous 1D stellar evolution
studies. We analyse the effect of accretion on the structure of a realistic
stellar model of the young Sun. Our work is inspired by the numerical work of
Kley \& Lin (1996, ApJ, 461, 933) devoted to the structure of the boundary
layer in accretion disks. We analyse the redistribution of accreted material
with a range of values of specific entropy relative to the bulk specific
entropy of the material in the accreting object's convective envelope. A
primary goal is to understand whether and how accreted energy deposited onto a
stellar surface is redistributed in the interior. This study focusses on the
high accretion rates characteristic of FU Ori systems. We find that the highest
entropy cases produce a distinctive behaviour in the mass redistribution, rms
velocities, and enthalpy flux in the convective envelope. This change in
behaviour is characterised by the formation of a hot layer on the surface of
the accreting object, which tends to suppress convection in the envelope. We
analyse the long-term effect of such a hot buffer zone on the structure and
evolution of the accreting object with 1D stellar evolution calculations. We
study the relevance of the assumption of redistribution of accreted energy into
the stellar interior used in the literature. One conclusion is that, for a
given amount of accreted energy transferred to the accreting object, a
treatment assuming accretion energy redistribution throughout the stellar
interior could significantly overestimate the effects on the stellar structure,
in particular, on the resulting expansion.


title:
Toroidal resonance: relation to pygmy mode, vortical properties and
  anomalous deformation splitting

abstract:
  We review a recent progress in investigation of the isoscalar toroidal dipole
resonance (TDR). A possible relation of the TDR and low-energy dipole strength
(also called a pygmy resonance) is analyzed. It is shown that the dipole
strength in the pygmy region can by understood as a local manifestation of the
collective vortical toroidal motion at the nuclear surface. Application of the
TDR as a measure of the nuclear dipole vorticity is discussed. Finally, an
anomalous splitting of the TDR in deformed nuclei is scrutinized.


title:
Non-linear uplift Ans\"atze for the internal metric and the four-form
  field-strength of maximal supergravity

abstract:
  The uplift of SO(8) gauged N=8 supergravity to 11-dimensional supergravity is
well studied in the literature. It is given by consistent relations between the
respective vector and scalar fields of both theories. For example, recent work
provided non-linear uplift Ans\"atze for the scalar degrees of freedom on the
internal manifold: the inverse metric and the three-form flux with mixed index
structure. However, one always found the metric of the compactified manifold by
inverting the inverse metric --- a task that was only possible in particular
cases, e.g. for the G$_2$, SO(3)$\times$SO(3) or SU(3)$\times$U(1)$\times$U(1)
invariant solutions of 11-dimensional supergravity.
  In this paper, I present a direct non-linear uplift Ansatz for the internal
metric in terms of the four-dimensional scalars and the Killing forms on the
compactified background manifold. Based on this formula, I also find new uplift
Ans\"atze for the warp factor and the full three-form flux. Finally, I provide
a direct non-linear uplift Ansatz for the internal four-form field-strength in
terms of the metric, the flux as well as the four-dimensional scalars and
background Killing forms. This new formula does not require to calculate the
derivative of the flux.
  My results may be generalized to other compactifications, e.g. the reduction
from type IIB supergravity to five dimensions.


title:
Degrees of Freedom Rate Region of the $K$-user Interference Channel with
  Blind CSIT Using Staggered Antenna Switching

abstract:
  In this paper, we consider the problem of the interference alignment for the
$K$-user SISO interference channel with blind channel state information at
transmitters (CSIT). Our achievement in contrast to popular $K-$user
interference alignment (IA) scheme has more practical notions. In this case
every receiver is equipped with one reconfigurable antenna which tries to place
its desired signal in a subspace which is linearly independent from
interference signals. We show that if the channel values are known to the
receivers only, the sum degrees-of-freedom (DOF) rate region of the linear BIA
with staggered antenna switching is $\frac{Kr}{r^2-r+K}$, where $r = \left
\lceil{\frac{\sqrt{1+4K}-1}{2}} \right \rceil$. The result indicates that the
optimum DoF rate region of the $K-$user interference channel is to achieve the
DoF of $\frac{\sqrt{K}}{2}$ for an asymptotically large network. Thus, the DoF
of the $K$-user interference channel using staggered antenna switching grows
sub-linearly with the number of the users, whereas it grows linearly in the
case where transmitters access the CSI. In addition we propose both
achievability and converse proof so as to show that this is the DoF rate region
of blind interference alignment (BIA) with staggered antenna switching.


title:
Late time accelerated scaling attractors in DGP
  (Dvali-Gabadadze-Porrati) braneworld

abstract:
  In the evolution of late universe, the main source of matter are Dark energy
and Dark matter. They are indirectly detected only through their gravitational
manifestations. So the possibility of interaction with each other without
violating observational restrictions is not ruled out. With this motivation, we
investigate the dynamics of DGP braneworld where source of dark energy is a
scalar field and it interacts with matter source. Since observation favours
phantom case more, we have also studied the dynamics of interacting phantom
scalar field. In non interacting DGP braneworld there are no late time
accelerated scaling attractors and hence cannot alleviate Coincidence problem.
In this paper, we shall show that it is possible to get late time accelerated
scaling solutions. The phase space is studied by taking two categories of
potentials (Exponential and Non exponential functions). The stability of
critical points are examined by taking two specific interactions. The first
interaction gives late time accelerated scaling solution for phantom field only
under exponential potential, while for second interaction we do not get any
scaling solution. Furthermore, we have shown that this scaling solution is also
classically stable.


title:
Comment on "Correlated impurities and intrinsic spin liquid physics in
  the kagome material Herbertsmithite" (T. H. Han et al., Phys. Rev. B 94,
  060409(R) (2016))

abstract:
  Recently Han et al. have provided an analysis of the observed behavior of
$\rm ZnCu_{3}(OH)_6Cl_2$ Herbertsmithite based on a separation of the
contributions to its thermodynamic properties due to impurities from those due
to the kagome lattice. The authors developed an impurity model to account for
the experimental data and claimed that it is compatible with the presence of a
small spin gap in the kagome layers. We argue that the model they advocate is
problematic, conflicting with the intrinsic properties of $\rm
ZnCu_{3}(OH)_6Cl_2$ as observed and explained in recent experimental and
theoretical investigations. We show that the existence of the gap in the kagome
layers is not in itself of a vital importance, for it does not govern the
thermodynamic and transport properties of $\rm ZnCu_3(OH)_6Cl_2$. Measurements
of heat transport in magnetic fields could clarify the quantum-critical
features of spin-liquid physics of $\rm ZnCu_{3}(OH)_6Cl_2$.


title:
Early Mars volcanic sulfur storage in the cryosphere and formation of
  transient SO2-rich atmospheres during the Hesperian

abstract:
  In a previous paper (Chassefi\`ere et al., Icarus 223, 878-891, 2013), we
have shown that most volcanic sulfur released to early Mars atmosphere could
have been trapped in the cryosphere under the form of CO2-SO2 clathrates. Huge
amounts of sulfur, up to the equivalent of a ~1 bar atmosphere of SO2, would
have been stored in the Noachian cryosphere, then massively released to the
atmosphere during Hesperian due to rapidly decreasing CO2 pressure. It would
have resulted in the formation of the large sulfate deposits observed mainly in
Hesperian terrains, whereas no or little sulfates are found at the Noachian. In
the present paper, we first clarify some aspects of our previous work. We
discuss the possibility of a smaller cooling effect of sulfur particles, or
even of a net warming effect. We point out the fact that CO2-SO2 clathrates
formed through a progressive enrichment of a preexisting reservoir of CO2
clathrates and discuss processes potentially involved in the slow formation of
a SO2-rich upper cryosphere. We show that episodes of sudden destabilization at
the Hesperian may generate 1000 ppmv of SO2 in the atmosphere and contribute to
maintaining the surface temperature above the water freezing point.


title: Polynomial Depth, Highness and Lowness for E

abstract:
  We study the relations between the notions of highness, lowness and logical
depth in the setting of complexity theory. We introduce a new notion of polylog
depth based on time bounded Kolmogorov complexity. We show polylog depth
satisfies all basic logical depth properties, namely sets in P are not polylog
deep, sets with (time bounded)-Kolmogorov complexity greater than polylog are
not polylog deep, and only polylog deep sets can polynomially Turing compute a
polylog deep set. We prove that if NP does not have p-measure zero, then NP
contains polylog deep sets. We show that every high set for E contains a
polylog deep set in its polynomial Turing degree, and that there exist
low(E,EXP) polylog deep sets. Keywords: algorithmic information theory;
Kolmogorov complexity; Bennett logical depth.


title:
A representation of a compressed de Bruijn graph for pan-genome analysis
  that enables search

abstract:
  Recently, Marcus et al. (Bioinformatics 2014) proposed to use a compressed de
Bruijn graph to describe the relationship between the genomes of many
individuals/strains of the same or closely related species. They devised an
$O(n \log g)$ time algorithm called splitMEM that constructs this graph
directly (i.e., without using the uncompressed de Bruijn graph) based on a
suffix tree, where $n$ is the total length of the genomes and $g$ is the length
of the longest genome. In this paper, we present a construction algorithm that
outperforms their algorithm in theory and in practice. Moreover, we propose a
new space-efficient representation of the compressed de Bruijn graph that adds
the possibility to search for a pattern (e.g. an allele - a variant form of a
gene) within the pan-genome.


title:
On a variational method for solving a class of $p$-Kirchhoff type
  problem

abstract:
  In this paper we are concerned with some $p$-Kirchhoff type problems
involving sign-changing weight functions. We prove the existence of multiple
positive solutions of the problem via the Nehari manifold approach.


title: Spin wave excitations in the tetragonal double perovskite Sr$_2$CuWO$_6$

abstract:
  Sr$_2$CuWO$_6$ is a double perovskite proposed to be at the border between
two and three dimensional magnetism, with a square lattice of $S=\frac{1}{2}$
Cu$^{2+}$ ions. We have used inelastic neutron scattering to investigate the
spin wave excitations of the system, to find out how they evolve as a function
of temperature, as well as to obtain information about the magnetic exchange
interactions. We observed well defined dispersive spin wave modes at $6$~K,
which partially survive above the magnetic ordering temperature, $T_N=24$~K.
Linear spin wave theory is used to determine the exchange interactions
revealing them to be highly two-dimensional in nature. Density functional
theory calculations are presented supporting this experimental finding, which
is in contrast to a previous \emph{ab-initio} study of the magnetic
interactions. Our analysis confirms that not the nearest neighbour, but the
next nearest neighbour interactions in the tetragonal $ab$ plane are the
strongest. Low incident energy measurements reveal the opening of a
$0.6(1)$~meV gap below $T_N$, which suggests the presence of a very weak single
ion anisotropy term in the form of an easy axis along $\hat{\mathbf{a}}$.


title: High energy particle collisions and geometry of horizon

abstract:
  We consider collision of two geodesic particles near the horizon of such an
axially symmetric black hole (rotating or static) that the metric coefficient
$g_{\phi \phi }\rightarrow 0$ there. It is shown that (both for regular and
singular horizons) the energy in the centre of mass frame $% E_{c.m.}$ is
indefinitely large even without fine-tuning of particles' parameters.
Kinematically, this is collision between two rapid particles that approach the
horizon almost with the speed of light but at different angles. The latter is
the reason why the relative velocity tends to that of light, hence to high
$E_{c.m.}$. Our approach is model-independent. It relies on general properties
of geometry and is insensitive to the details of material source that supports
the geometies of the type under consideration. For several particular models
(the stringy black hole, the Brans-Dicke analogue of the Schwarzschild metric
and the Janis-Newman-Winicour one) we recover the results found in literature
previously.


title: Enhancing Patient Appointments Scheduling that Uses Mobile Technology

abstract:
  Appointment scheduling systems are utilized mainly by specialty care clinics
to manage access to service providers as well as by hospitals to schedule
patient appointments. When attending hospitals in Tanzania, patients experience
challenges to see an appropriate specialist doctor because of service interval
inconsistency. Timely availability of doctors is critical whenever a patient
needs to see a specialist doctor for treatment and a serious bottleneck lies in
the application of appropriate technology techniques to enhance appointment
scheduling. In this paper, we present a mobile based application scheduling
system for managing patient appointments. Furthermore, forthcoming
opportunities for the innovative use of the mobile based application scheduling
system are identified.


title: On a new property of $n$-poised and $GC_n$ sets

abstract:
  In this paper we consider n-poised planar node sets, as well as more special
ones, called $GC_n$-sets. For these sets all $n$-fundamental polynomials are
products of n linear factors as it always takes place in the univariate case. A
line ${\ell}$ is called $k$-node line for a node set $\mathcal X$ if it passes
through exactly $k$ nodes. An $(n+1)$-node line is called maximal line. In 1982
M. Gasca and J. I. Maeztu conjectured that every $GC_n$-set possesses
necessarily a maximal line. Till now the conjecture is confirmed to be true for
$n \le 5$. It is well-known that any maximal line $M$ of $\mathcal X$ is used
by each node in $\mathcal X\setminus M,$ meaning that it is a factor of the
fundamental polynomial of each node. In this paper we prove, in particular,
that if the Gasca-Maeztu conjecture is true then any $n$-node line of
$GC_n$-set $\mathcal X$ is used either by exactly $\binom{n}{2}$ nodes or by
exactly $\binom{n-1}{2}$ nodes. We prove also similar statements concerning
$n$-node or $(n-1)$-node lines in more general $n$-poised sets. This is a new
phenomenon in $n$-poised and $GC_n$ sets. At the end we present a conjecture
concerning any $k$-node line.


title: Attractors for the strongly damped wave equation with $p$-Laplacian

abstract:
  This paper is concerned with the initial boundary value problem for one
dimensional strongly damped wave equation involving $p$-Laplacian. For $p>2$,
we establish the existence of weak local attractors for this problem in
$W_{0}^{1,p}(0,1)\times L^{2}(0,1)$. Under restriction $2<p<4$, we prove that
the semigroup, generated by the considered problem, possesses a strong global
attractor in $W_{0}^{1,p}(0,1)\times L^{2}(0,1)$ and this attractor is a
bounded subset of $W^{1,\infty }(0,1)\times W^{1,\infty }(0,1)$.


title:
Structure formation in a colliding flow: The Herschel view of the Draco
  nebula

abstract:
  The Draco nebula is a high Galactic latitude interstellar cloud likely to
have been formed by the collision of a Galactic halo cloud entering the disk of
the Milky Way. Such conditions are ideal to study the formation of cold and
dense gas in colliding flows of warm gas. We present Herschel-SPIRE
observations that reveal the fragmented structure of the interface between the
infalling cloud and the Galactic layer. This front is characterized by a
Rayleigh-Taylor instability structure. From the determination of the typical
length of the periodic structure (2.2 pc) we estimated the gas kinematic
viscosity and the turbulence dissipation scale (0.1 pc) that is compatible with
that expected if ambipolar diffusion is the main mechanism of energy
dissipation in the WNM. The small-scale structures of the nebula are typical of
that seen in some molecular clouds. The gas density has a log-normal
distribution with an average value of $10^3$ cm$^{-3}$. The size of the
structures is 0.1-0.2 pc but this estimate is limited by the resolution of the
observations. The mass ranges from 0.2 to 20 M$_{\odot}$ and the distribution
of the more massive clumps follows a power law $dN/d\log(M) \sim M^{-1.4}$. We
identify a mass-size relation with the same exponent as that found in GMCs
($M\sim L^{2.3}$) but only 15% of the mass of the cloud is in gravitationally
bound structures. We conclude that the increase of pressure in the collision is
strong enough to trigger the WNM-CNM transition caused by the interplay between
turbulence and thermal instability as self-gravity is not dominating the
dynamics.


title: Non-noetherian groups and primitivity of their group algebras

abstract:
  We prove that the group algebra $KG$ of a group $G$ over a field $K$ is
primitive, provided that $G$ has a free subgroup with the same cardinality as
$G$, and that $G$ satisfies the following condition $(\ast)$: for each subset
$M$ of $G$ consisting of a finite number of elements not equal to $1$, and for
any positive integer $m$, there exist distinct $a$, $b$, and $c$ in $G$ so that
if $(x_{1}^{-1}g_1x_{1}) \cdots (x_{m}^{-1}g_mx_{m})=1$, where $g_i$ is in $M$
and $x_i$ is equal to $a$, $b$, or $c$ for all $i$ between $1$ and $m$, then
$x_{i}=x_{i+1}$ for some $i$. This generalizes results of \cite{Bal},
\cite{For}, \cite{Ni07}, and \cite{Ni11}, and proves that, for every countably
infinite group $G$ satisfying $(\ast)$, $KG$ is primitive for any field $K$. We
use this result to determine the primitivity of group algebras of one relator
groups with torsion.


title: The Case for Data Plane Timestamping in SDN

abstract:
  This paper presents the case for Data Plane Timestamping (DPT). We argue that
in the unique environment of Software-Defined Networks (SDN), attaching a
timestamp to the header of all packets is a powerful feature that can be
leveraged by various diverse SDN applications. We analyze three key use cases
that demonstrate the advantages of using DPT, and show that SDN applications
can benefit even from using as little as one bit for the timestamp field.


title:
Viscoelasticity of reversibly crosslinked networks of semiflexible
  polymers

abstract:
  We present a theoretical framework for the linear and nonlinear visco-elastic
properties of reversibly crosslinked networks of semiflexible polymers. In
contrast to affine models where network strain couples to the polymer
end-to-end distance, in our model strain rather serves to locally distort the
network structure. This induces bending modes in the polymer filaments, the
properties of wich are slaved to the surrounding network structure.
Specifically, we investigate the frequency-dependent linear rheology, in
particular in combination with crosslink binding/unbinding processes. We also
develop schematic extensions to describe the nonlinear response during creep
measurements as well as during constant-strainrate ramps.


title: A 750 GeV Diphoton Signal from a Very Light Pseudoscalar in the NMSSM

abstract:
  The excess of events in the diphoton final state near 750 GeV observed by
ATLAS and CMS can be explained within the NMSSM near the R-symmetry limit. Both
scalars beyond the Standard Model Higgs boson have masses near 750 GeV, mix
strongly, and share sizeable production cross sections in association with
b-quarks as well as branching fractions into a pair of very light
pseudoscalars. Pseudoscalars with a mass of ~ 210 MeV decay into collimated
diphotons, whereas pseudoscalars with a mass of ~ 500-550 MeV can decay either
into collimated diphotons or into three pi^0 resulting in collimated photon
jets. Various such scenarios are discussed; the dominant constraints on the
latter scenario originate from bounds on radiative Upsilon decays, but they
allow for a signal cross section up to 6.7 fb times the acceptance for
collimated multiphotons to pass as a single photon.


title:
Spatial correlations, additivity and fluctuations in conserved-mass
  transport processes

abstract:
  We exactly calculate two-point spatial correlation functions in steady state
in a broad class of conserved-mass transport processes, which are governed by
chipping, diffusion and coalescence of masses. We find that the spatial
correlations are in general short-ranged and consequently, on a large scale,
these conserved-mass transport processes possess a remarkable thermodynamic
structure in the steady state. That is, the processes have an equilibriumlike
additivity property, and a corresponding fluctuation-response relation, which
helps us to obtain subsystem mass distributions in the limit of subsystem size
large.


title: DAP3D-Net: Where, What and How Actions Occur in Videos?

abstract:
  Action parsing in videos with complex scenes is an interesting but
challenging task in computer vision. In this paper, we propose a generic 3D
convolutional neural network in a multi-task learning manner for effective Deep
Action Parsing (DAP3D-Net) in videos. Particularly, in the training phase,
action localization, classification and attributes learning can be jointly
optimized on our appearancemotion data via DAP3D-Net. For an upcoming test
video, we can describe each individual action in the video simultaneously as:
Where the action occurs, What the action is and How the action is performed. To
well demonstrate the effectiveness of the proposed DAP3D-Net, we also
contribute a new Numerous-category Aligned Synthetic Action dataset, i.e.,
NASA, which consists of 200; 000 action clips of more than 300 categories and
with 33 pre-defined action attributes in two hierarchical levels (i.e.,
low-level attributes of basic body part movements and high-level attributes
related to action motion). We learn DAP3D-Net using the NASA dataset and then
evaluate it on our collected Human Action Understanding (HAU) dataset.
Experimental results show that our approach can accurately localize, categorize
and describe multiple actions in realistic videos.


title: Can one measure the Cosmic Neutrino Background?

abstract:
  The Cosmic Microwave Background (CMB) yields information about our Universe
at around 380 000 years after the Big Bang (BB). Due to the weak interaction of
the neutrinos with matter the Cosmic Neutrino Background (CNB) should give
information about a much earlier time of our Universe, around one second after
the Big Bang. Probably the most promising method to `see' the Cosmic Neutrino
Background is the capture of the electron neutrinos from the Background by
Tritium, which then decays into 3He and an electron with the energy of the the
Q-value = 18.562 keV plus the electron neutrino rest mass. The `KArlsruhe
TRItium Neutrino' (KATRIN) experiment, which is in preparation, seems presently
the most sensitive proposed method for measuring the electron antineutrino
mass. At the same time KATRIN can also look by the reaction: electron neutrino
(~1.95 Kelvin) + 3H --> 3He + e- (with the energy Q = 18.6 keV + electron
neutrino mass). The capture of the Cosmic Background Neutrinos (CNB) should
show in the electron spectrum as a peak by the electron neutrino rest mass
above Q. Here the possibility to see the CNB with KATRIN is studied. A
detection of the CNB by KATRIN seems not to be possible at the moment. But
KATRIN should be able to determine an upper limit for the local electron
neutrino density of the CNB.


title: Iterative Hierarchical Optimization for Misspecified Problems (IHOMP)

abstract:
  For complex, high-dimensional Markov Decision Processes (MDPs), it may be
necessary to represent the policy with function approximation. A problem is
misspecified whenever, the representation cannot express any policy with
acceptable performance. We introduce IHOMP : an approach for solving
misspecified problems. IHOMP iteratively learns a set of context specialized
options and combines these options to solve an otherwise misspecified problem.
Our main contribution is proving that IHOMP enjoys theoretical convergence
guarantees. In addition, we extend IHOMP to exploit Option Interruption (OI)
enabling it to decide where the learned options can be reused. Our experiments
demonstrate that IHOMP can find near-optimal solutions to otherwise
misspecified problems and that OI can further improve the solutions.


title:
The Floquet-Bloch Transform and Scattering from Locally Perturbed
  Periodic Surfaces

abstract:
  We use the Floquet-Bloch transform to reduce variational formulations of
surface scattering problems for the Helmholtz equation from periodic and
locally perturbed periodic surfaces to equivalent variational problems
formulated on bounded domains. To this end, we establish various mapping
properties of that transform between suitable weighted Sobolev spaces on
periodic strip-like domains and coupled families of quasiperiodic Sobolev
spaces. Our analysis shows in particular that the decay of solutions to surface
scattering problems from locally perturbed periodic surfaces is precisely
characterized by the smoothness of its Bloch transform in the quasiperiodicity.


title:
Query Processing For The Internet-of-Things: Coupling Of Device Energy
  Consumption And Cloud Infrastructure Billing

abstract:
  Audio/visual recognition and retrieval applications have recently garnered
significant attention within Internet-of-Things (IoT) oriented services, given
that video cameras and audio processing chipsets are now ubiquitous even in
low-end embedded systems. In the most typical scenario for such services, each
device extracts audio/visual features and compacts them into feature
descriptors, which comprise media queries. These queries are uploaded to a
remote cloud computing service that performs content matching for
classification or retrieval applications. Two of the most crucial aspects for
such services are: (i) controlling the device energy consumption when using the
service; (ii) reducing the billing cost incurred from the cloud infrastructure
provider. In this paper we derive analytic conditions for the optimal coupling
between the device energy consumption and the incurred cloud infrastructure
billing. Our framework encapsulates: the energy consumption to produce and
transmit audio/visual queries, the billing rates of the cloud infrastructure,
the number of devices concurrently connected to the same cloud server, and the
statistics of the query data production volume per device. Our analytic results
are validated via a deployment with: (i) the device side comprising compact
image descriptors (queries) computed on Beaglebone Linux embedded platforms and
transmitted to Amazon Web Services (AWS) Simple Storage Service; (ii) the cloud
side carrying out image similarity detection via AWS Elastic Compute Cloud
(EC2) spot instances, with the AWS Auto Scaling being used to control the
number of instances according to the demand.


abstract:
  We introduce the Adaptive Skills, Adaptive Partitions (ASAP) framework that
(1) learns skills (i.e., temporally extended actions or options) as well as (2)
where to apply them. We believe that both (1) and (2) are necessary for a truly
general skill learning framework, which is a key building block needed to scale
up to lifelong learning agents. The ASAP framework can also solve related new
tasks simply by adapting where it applies its existing learned skills. We prove
that ASAP converges to a local optimum under natural conditions. Finally, our
experimental results, which include a RoboCup domain, demonstrate the ability
of ASAP to learn where to reuse skills as well as solve multiple tasks with
considerably less experience than solving each task from scratch.


title: Valley-protected backscattering suppression in silicon photonic graphene

abstract:
  In this paper, we study valley degree of freedom in all dielectric silicon
photonic graphene. Photonic band gap opening physics under inversion symmetry
breaking is revisited by the viewpoint of nonzero valley Chern number. Bulk
valley modes with opposite orbital angular momentum are unveiled by inspecting
time-varying electric fields. Topological transition is well illustrated
through photonic Dirac Hamiltonian. Valley dependent edge states and the
associated valley-protected backscattering suppression around Z-shape bend
waveguide have been demonstrated.


title:
Are leaves optimally designed for self-support? An investigation on
  giant monocots

abstract:
  Leaves are the organs that intercept light and create photosynthesis.
Efficient light interception is provided by leaves oriented orthogonal to most
of the sun rays. Except in the polar regions, this means orthogonal to the
direction of acceleration due to gravity, or simply horizontal. The leaves of
almost all terrestrial plants grow in a gravity field that tends to bend them
downward and therefore may counteract light interception. Plants thus allocate
biomass for self-support in order to maintain their leaves horizontal. To
compete with other species (inter-species competition), as well as other
individuals within the same species (intra-species competition), self-support
must be achieved with the least biomass produced. This study examines to what
extent leaves are designed to self-support. We show here that a basic
mechanical model provides the optimal dimensions of a leaf for light
interception and self-support. These results are compared to measurements made
on leaves of various giant monocot species,especially palm trees and banana
trees. The comparison between experiments and model predictions shows that the
longer palms are optimally designed for self-support whereas shorter leaves are
shaped predominantly by other parameters of selection.


title: On the Topological degree of the Mean field equation with two parameters

abstract:
  We consider the following class of equations with exponential nonlinearities
on a compact surface $M$: $$
  - \Delta u = \rho_1 \left( \frac{h_1 \,e^{u}}{\int_M
  h_1 \,e^{u} } - \frac{1}{|M|} \right) - \rho_2 \left( \frac{h_2
\,e^{-u}}{\int_M
  h_2 \,e^{-u} } - \frac{1}{|M|} \right), $$ which is associated to the mean
field equation of the equilibrium turbulence with arbitrarily signed vortices.
Here $h_1, h_2$ are smooth positive functions and $\rho_1, \rho_2$ are two
positive parameters.
  We start by proving a concentration phenomena for the above equation, which
leads to a-priori bound for the solutions of this problem provided
$\rho_i\notin 8\pi\mathbb{N}, \, i=1,2$.
  Then we study the blow up behavior when $\rho_1$ crosses $8\pi$ and $\rho_2
\notin 8\pi\mathbb{N}$. By performing a suitable decomposition of the above
equation and using the shadow system that was introduced for the $SU(3)$ Toda
system, we can compute the Leray-Schauder topological degree for $\rho_1 \in
(0,8\pi) \cup (8\pi,16\pi)$ and $\rho_2 \notin 8\pi\mathbb{N}$.
  As a byproduct our argument, we give new existence results when the
underlying manifold is a sphere and a new proof for some known existence
result.


title: Freezing and melting line invariants of the Lennard-Jones system

abstract:
  The invariance of several structural and dynamical properties of the
Lennard-Jones (LJ) system along the freezing and melting lines is interpreted
in terms of the isomorph theory. First the freezing/melting lines for LJ system
are shown to be approximated by isomorphs. Then we show that the invariants
observed along the freezing and melting isomorphs are also observed on other
isomorphs in the liquid and crystalline phase. Structure is probed by the
radial distribution function and the structure factor and dynamics is probed by
the mean-square displacement, the intermediate scattering function, and the
shear viscosity. Studying these properties by reference to the isomorph theory
explains why known single-phase melting criteria holds, e.g., the Hansen-Verlet
and the Lindemann criterion, and why the Andrade equation for the viscosity at
freezing applies, e.g., for most liquid metals. Our conclusion is that these
empirical rules and invariants can all be understood from the isomorph theory
and that the invariants are not peculiar to the freezing and melting lines, but
hold along all isomorphs.


title: Infinitely many monotone Lagrangian tori in del Pezzo surfaces

abstract:
  We construct almost toric fibrations (ATFs) on all del Pezzo surfaces,
endowed with a monotone symplectic form. Except for $\mathbb{C}P^2 \# 1
\overline{\mathbb{C}P^2}$ and $\mathbb{C}P^2 \# 2 \overline{\mathbb{C}P^2}$ ,
we are able to get almost toric base diagrams (ATBDs) of triangular shape and
prove the existence of infinitely many symplectomorphism (in particular
Hamiltonian isotopy) classes of monotone Lagrangian tori in $\mathbb{C}P^2 \# k
\overline{\mathbb{C}P^2}$, for k=0,3,4,5,6,7,8. We name these tori
$\Theta^{n_1,n_2,n_3}_{p,q,r}$. Using the work of Karpov-Nogin, we are able to
classify all ATBDs of triangular shape. We are able to prove that
$\mathbb{C}P^2 \# 1 \overline{\mathbb{C}P^2}$ also have infinitely many
monotone Lagrangian tori up to symplectomorphism and we conjecture that the
same holds for $\mathbb{C}P^2 \# 2 \overline{\mathbb{C}P^2}$ . Finally, the
Lagrangian tori $\Theta^{n_1,n_2,n_3}_{p,q,r}$ inside a del Pezzo surface $X$
can be seen as monotone fibres of ATFs, such that, over its edge lies a fixed
anticanonical symplectic torus $\Sigma$. We argue that
$\Theta^{n_1,n_2,n_3}_{p,q,r}$ give rise to infinitely many exact Lagrangian
tori in $X \setminus \Sigma$, even after attaching the positive end of a
symplectization to the boundary of $X \setminus \Sigma$.


title:
Optimization of the shape (and topology) of the initial conditions for
  diffusion parameter identification

abstract:
  The design of an experiment, e.g., the setting of initial conditions,
strongly influences the accuracy of the whole process of determining model
parameters from data. We impose a sensitivity-based approach for choosing
optimal design variables and study the optimization of the shape (and topology)
of the initial conditions for an inverse problem of a diffusion parameter
identification. Our approach, although case independent, is illustrated at the
FRAP (Fluorescence Recovery After Photobleaching) experimental technique. The
core idea resides in the maximization of a sensitivity measure, which depends
on a specific experimental setting of initial conditions. By a numerical
optimization, we find an interesting pattern of increasingly complicated (with
respect to connectivity) optimal initial shapes. The proposed modification of
the FRAP experimental protocol is rather surprising but entirely realistic and
the resulting enhancement of the parameter estimate accuracy is significant.


title: Bloch functions, asymptotic variance, and geometric zero packing

abstract:
  We study a new type of extremal problem in complex analysis, referred to as
"geometric zero packing", which is the hyperbolic analogue of a problem
considered by Abrikosov in the 1950s concerning Bose-Einstein condensates. We
relate the corresponding minimal discrepancy density with the asymptotic
variance for Bloch functions of the form "Bergman projection of bounded
functions" and obtain a corresponding identity. Together with related work of
Ivrii, this gives the asymptotic behavior of the universal quasiconformal
integral means spectrum for small values of quasiconformality k and small
exponents t. In particular, the conjectured behavior is shown to be smaller
than conjectured by Prause and Smirnov, which also shows that there are no
quasidisks with dimension 1+k^2, at least for small k.


title: The variable spin-down rate of the transient magnetar XTE J1810--197

abstract:
  We have analyzed XMM-Newton and Chandra observations of the transient
magnetar XTE J1810-197, spanning more than 11 years, from the initial phases of
the 2003 outburst to the current quiescent level. We investigated the evolution
of the pulsar spin period and we found evidence for two distinct regimes:
during the outburst decay, the spin derivative (nu_dot) was highly variable in
the range -(2-4.5)x10^-13 Hz/s, while during quiescence the spin-down rate was
more stable at an average value of -1x10^{-13} Hz/s. Only during ~3000 days
(from MJD 54165 to MJD 56908) in the quiescent stage, it was possible to find a
phase-connected timing solution, with nu_dot = -4.9x10^{-14} Hz/s, and a
positive second frequency derivative, nu_dotdot = 1.8x10^{-22} Hz/s. These
results are in agreement with the behavior expected if the outburst of XTE
J1810-197 was due to a strong magnetospheric twist.


title: Matrix Decompositions using sub-Gaussian Random Matrices

abstract:
  In recent years, several algorithms, which approximate matrix decomposition,
have been developed. These algorithms are based on metric conservation features
for linear spaces of random projection types. We show that an i.i.d
sub-Gaussian matrix with large probability to have zero entries is metric
conserving. We also present a new algorithm, which achieves with high
probability, a rank $r$ decomposition approximation for an $m \times n$ matrix
that has an asymptotic complexity like state-of-the-art algorithms. We derive
an error bound that does not depend on the first $r$ singular values. Although
the proven error bound is not as tight as the state-of-the-art bound,
experiments show that the proposed algorithm is faster in practice, while
getting the same error rates as the state-of-the-art algorithms get.