title:
Lateral IBIC characterization of single crystal synthetic diamond
  detectors

abstract:
  In order to evaluate the charge collection efficiency (CCE) profile of
single-crystal diamond devices based on a p type/intrinsic/metal configuration,
a lateral Ion Beam Induced Charge (IBIC) analysis was performed over their
cleaved cross sections using a 2 MeV proton microbeam. CCE profiles in the
depth direction were extracted from the cross-sectional maps at variable bias
voltage. IBIC spectra relevant to the depletion region extending beneath the
frontal Schottky electrode show a 100% CCE, with a spectral resolution of about
1.5%. The dependence of the width of the high efficiency region from applied
bias voltage allows the constant residual doping concentration of the active
region to be evaluated. The region where the electric field is absent shows an
exponentially decreasing CCE profile, from which it is possible to estimate the
diffusion length of the minority carriers by means of a drift-diffusion model.


title:
Focused ion beam fabrication and IBIC characterization of a diamond
  detector with buried electrodes

abstract:
  This paper reports on the fabrication and characterization of a high purity
monocrystalline diamond detector with buried electrodes realized by the
selective damage induced by a focused 6 MeV carbon ion beam scanned over a
pattern defined at the micrometric scale. A suitable variable-thickness mask
was deposited on the diamond surface in order to modulate the penetration depth
of the ions and to shallow the damage profile toward the surface. After the
irradiation, the sample was annealed at high temperature in order to promote
the conversion to the graphitic phase of the end-of-range regions which
experienced an ion-induced damage exceeding the damage threshold, while
recovering the sub-threshold damaged regions to the highly resistive diamond
phase. This process provided conductive graphitic electrodes embedded in the
insulating diamond matrix; the presence of the variable-thickness mask made the
terminations of the channels emerging at the diamond surface and available to
be connected to an external electronic circuit. In order to evaluate the
quality of this novel microfabrication procedure based on direct ion writing,
we performed frontal Ion Beam Induced Charge (IBIC) measurements by raster
scanning focused MeV ion beams onto the diamond surface. Charge collection
efficiency (CCE) maps were measured at different bias voltages. The
interpretation of such maps was based on the Shockley-Ramo-Gunn formalism.


title: An algorithm for dividing two complex numbers

abstract:
  In this work a rationalized algorithm for calculating the quotient of two
complex numbers is presented which reduces the number of underlying real
multiplications. The performing of a complex number division using the naive
method takes 4 multiplications, 3 additions, 2 squarings and 2 divisions of
real numbers while the proposed algorithm can compute the same result in only 3
multiplications ( or multipliers in hardware implementation case), 6 additions,
2 squarings and 2 divisions of real numbers.


title: A Randomized Approach to Efficient Kernel Clustering

abstract:
  Kernel-based K-means clustering has gained popularity due to its simplicity
and the power of its implicit non-linear representation of the data. A dominant
concern is the memory requirement since memory scales as the square of the
number of data points. We provide a new analysis of a class of approximate
kernel methods that have more modest memory requirements, and propose a
specific one-pass randomized kernel approximation followed by standard K-means
on the transformed data. The analysis and experiments suggest the method is
accurate, while requiring drastically less memory than standard kernel K-means
and significantly less memory than Nystrom based approximations.


title:
Likelihood Ratio as Weight of Forensic Evidence: A Metrological
  Perspective

abstract:
  In this article we provide a rebuttal against the possible perception that a
single number, such as the Likelihood Ratio, can provide an objective,
authoritative or definitive weight of evidence. We also illustrate the extent
to which conclusions can vary depending on the assumptions used in the
analysis, even under alternative assumptions that are judged to be consistent
with available empirical information. To facilitate these goals, we introduce
the notion of a Lattice of Assumptions and an Uncertainty Pyramid illustrated
in the context of a previously published example involving glass evidence. We
take the position that rather than focusing on a single number summary as the
weight of evidence it is the duty of the forensic expert to assist the trier of
fact in forming their own interpretations from a clear understanding of the
objective and demonstrably available information. We hope the presented
arguments will inspire those in the forensic science community to pursue
establishing their practice on a solid foundation of measurement science.


title:
Bond patterns and charge order amplitude in 1/4-filled charge-transfer
  solids

abstract:
  Metal-insulator transition accompanied by charge-ordering has been widely
investigated in quasi-one-dimensional conductors, including in particular
organic charge-transfer solids. Among such materials the 1/4-filled band
charge-transfer solids are of strong interest, because of the commensurate
nature of the charge-ordering in these systems. The period-four charge-order
pattern ...1100... here is accompanied by two distinct bond distortion
patterns, giving rise to bond-charge-density waves (BCDW) of types 1 and 2.
Using quantum Monte Carlo methods, we determine the phase diagram within the
extended Hubbard Hamiltonian that gives both types 1 and 2 BCDW in the
thermodynamic limit. We further investigate the effect of electron-electron and
electron-phonon interactions on the amount of charge disproportionation. Our
results show that between these two bond patterns, one (BCDW2) in general
coexists with a large magnitude charge order, which is highly sensitive to
electron-phonon interactions, while the other (BCDW1) is characterized by weak
charge order. We discuss the relevance of our work to experiments on several
1/4-filled conductors, focusing in particular on the materials (EDO-TTF)_2X and
(DMEDO-TTF)_2X with large amplitude charge-order.


title: Equimultiplicity in Hilbert-Kunz theory

abstract:
  This paper develops a theory of equimultiplicity for Hilbert-Kunz
multiplicity and uses it to study the behavior of Hilbert-Kunz multiplicity on
the Brenner- Monsky hypersurface. A number of applications follows, in
particular we show that Hilbert-Kunz multiplicity attains infinitely many
values and that equimultiple strata may not be locally closed.


title: The Differential Virial Theorem with Gradient Formulas for the Operators

abstract:
  A gradient dependent formula is derived for the spinless one-particle
density-matrix operator z from the differential virial theorem. A gradient
dependent formula is also derived for a spinless one-particle density-matrix
operator that can replace the two operators of the differential virial theorem
that arise from the kinetic energy operator. Other operators are also derived
that can replace the operators mentioned above in the differential virial
theorem; these operators depend on the real part of spinless one-particle
density-matrix.


title:
Temperature of a nanoparticle above a substrate under radiative heating
  and cooling

abstract:
  Controlling the temperature in architectures involving nanoparticles and
substrates is a key issue for applications involving micro and nanoscale heat
transfer. We study the thermal behavior of a single nanoparticle interacting
with a flat substrate under external monochromatic illumination, and with
thermal radiation as the unique heat loss channel. We develop a model to
compute the temperature of the nanoparticle, based on an effective
dipole-polarizability approach. Using numerical simulations, we thoroughly
investigate the impacts of various parameters affecting the nanoparticle
temperature, such as the nanoparticle-to-substrate gap distance, the incident
light wavelength and polarization, or the material resonances. This study
provides a tool for the thermal characterization and design of micro or
nanoscale systems coupling substrates with nanoparticles or optical antennas.


title: Optical cavity for enhanced parametric four-wave mixing in rubidium

abstract:
  We demonstrate the implementation of a ring cavity to enhance the efficiency
of parametric four-wave mixing in rubidium. Using an input coupler with 95%
reflectance, a finesse of 19.6$\pm$0.5 is achieved with a rubidium cell inside.
This increases the circulating intensity by a factor of 5.6$\pm$0.5, and
through two-photon excitation on the $5s_{1/2}\rightarrow5d_{5/2}$ transition
with a single excitation laser, up to 1.9$\pm$0.3 mW of power at 420 nm is
generated, 50 times what was previously generated with this scheme. The
dependence of the output on Rb density and input power has been explored,
suggesting the process may be approaching saturation. The blue output of the
cavity also shows greatly improved spatial quality, combining to make this a
promising source of 420 nm light for future experiments.


title:
Regularity problem for the nematic LCD system with Q-tensor in $\mathbb
  R^3$

abstract:
  We study the regularity problem of a nematic liquid crystal model with local
configuration represented by Q-tensor in three dimensions. It was an open
question whether the classical Prodi-Serrin condition implies regularity for
this model. Applying a wavenumber splitting method, we show that a solution
does not blow-up under certain extended Beale-Kato-Majda condition solely
imposed on velocity. This regularity criterion automatically implies that the
classical Prodi-Serrin or Beale-Kato-Majda condition prevents blow-up of
solutions.


title: Clustering and Community Detection with Imbalanced Clusters

abstract:
  Spectral clustering methods which are frequently used in clustering and
community detection applications are sensitive to the specific graph
constructions particularly when imbalanced clusters are present. We show that
ratio cut (RCut) or normalized cut (NCut) objectives are not tailored to
imbalanced cluster sizes since they tend to emphasize cut sizes over cut
values. We propose a graph partitioning problem that seeks minimum cut
partitions under minimum size constraints on partitions to deal with imbalanced
cluster sizes. Our approach parameterizes a family of graphs by adaptively
modulating node degrees on a fixed node set, yielding a set of parameter
dependent cuts reflecting varying levels of imbalance. The solution to our
problem is then obtained by optimizing over these parameters. We present
rigorous limit cut analysis results to justify our approach and demonstrate the
superiority of our method through experiments on synthetic and real datasets
for data clustering, semi-supervised learning and community detection.


title:
astroABC: An Approximate Bayesian Computation Sequential Monte Carlo
  sampler for cosmological parameter estimation

abstract:
  Given the complexity of modern cosmological parameter inference where we are
faced with non-Gaussian data and noise, correlated systematics and multi-probe
correlated data sets, the Approximate Bayesian Computation (ABC) method is a
promising alternative to traditional Markov Chain Monte Carlo approaches in the
case where the Likelihood is intractable or unknown. The ABC method is called
"Likelihood free" as it avoids explicit evaluation of the Likelihood by using a
forward model simulation of the data which can include systematics. We
introduce astroABC, an open source ABC Sequential Monte Carlo (SMC) sampler for
parameter estimation. A key challenge in astrophysics is the efficient use of
large multi-probe datasets to constrain high dimensional, possibly correlated
parameter spaces. With this in mind astroABC allows for massive parallelization
using MPI, a framework that handles spawning of jobs across multiple nodes. A
key new feature of astroABC is the ability to create MPI groups with different
communicators, one for the sampler and several others for the forward model
simulation, which speeds up sampling time considerably. For smaller jobs the
Python multiprocessing option is also available. Other key features include: a
Sequential Monte Carlo sampler, a method for iteratively adapting tolerance
levels, local covariance estimate using scikit-learn's KDTree, modules for
specifying optimal covariance matrix for a component-wise or multivariate
normal perturbation kernel, output and restart files are backed up every
iteration, user defined metric and simulation methods, a module for specifying
heterogeneous parameter priors including non-standard prior PDFs, a module for
specifying a constant, linear, log or exponential tolerance level,
well-documented examples and sample scripts. This code is hosted online at
https://github.com/EliseJ/astroABC


title:
The Bluedisk Survey: molecular gas distribution and scaling relations in
  the context of galaxy evolution

abstract:
  One of the key goals of the Bluedisk survey is to characterize the impact of
gas accretion in disc galaxies in the context of galaxy evolution. It contains
50 disc galaxies in the stellar mass range 10^10-10^11 Msun, of which half are
bluer and more HI-rich galaxies than their HI-normal (control) counterparts. In
this paper, we investigate how ongoing disc growth affects the molecular gas
distribution and the star-formation efficiency in these galaxies. We present
12CO observations from the IRAM 30-m telescope in 26 galaxies of the Bluedisk
survey. We compare the amount and spatial distribution of the molecular gas to
key quantities such as atomic gas, stellar mass and surface density,
star-formation rate and metallicity. We analyse the star-formation rate per
unit gas (SFR/HI and SFR/H2) and relate all those parameters to general galaxy
properties (HI-rich/control disc, morphology, etc.). We find that the HI-rich
galaxies have similar H2 masses as the control galaxies. In their centres,
HI-rich galaxies have lower H2/HI ratios and marginally shorter molecular gas
depletion times. However, the main differences between the two samples occur in
the outer parts of the discs, with the HI-rich galaxies having slightly smaller
CO discs (relative to the optical radius R25) and steeper CO and metallicity
gradients than the control galaxies. The ongoing accretion of HI at large radii
has thus not led to an appreciable growth of the CO discs in our sample. Based
on depletion times, we estimate that this gas will contribute to star formation
on time-scales of at least 5 Gyr.


title:
Evolution of forced shear flows in polytropic atmospheres: A comparison
  of forcing methods and energetics

abstract:
  Shear flows are ubiquitous in astrophysical objects including planetary and
stellar interiors, where their dynamics can have significant impact on
thermo-chemical processes. Investigating the complex dynamics of shear flows
requires numerical calculations that provide a long time evolution of the
system. To achieve a sufficiently long lifetime in a local numerical model the
system has to be forced externally. However, at present, there exist several
different forcing methods to sustain large-scale shear flows in local models.
In this paper we examine and compare various methods used in the literature in
order to resolve their respective applicability and limitations. These
techniques are compared during the exponential growth phase of a shear flow
instability, such as the Kelvin-Helmholtz (KH) instability, and some are
examined during the subsequent non-linear evolution. A linear stability
analysis provides reference for the growth rate of the most unstable modes in
the system and a detailed analysis of the energetics provides a comprehensive
understanding of the energy exchange during the system's evolution. Finally, we
discuss the pros and cons of each forcing method and their relation with
natural mechanisms generating shear flows.


title: The Smallest Positive Eigenvalue Of Fibered Hyperbolic 3-Manifolds

abstract:
  We study the smallest positive eigenvalue $\lambda_1(M)$ of the
Laplace-Beltrami operator on a closed hyperbolic 3-manifold $M$ which fibers
over the circle, with fiber a closed surface of genus $g\geq 2$.
  We show the existence of a constant $C>0$ only depending on $g$ so that
$\lambda_1(M)\in [C^{-1}/{\rm vol}(M)^2, C\log {\rm vol}(M)/{\rm
vol}(M)^{2^{2g-2}/(2^{2g-2}-1)}]$ and that this estimate is essentially sharp.
We show that if $M$ is typical or random, then we have $\lambda_1(M)\in
[C^{-1}/{\rm vol}(M)^2,C/{\rm vol}(M)^2]$. This rests on a result of
independent interest about reccurence properties of axes of random
pseudo-Anosov elements.


title: NSV 1907 - A new eclipsing, nova-like cataclysmic variable

abstract:
  NSV 1907, formerly listed as an irregular variable in variability catalogues,
was classified as an Algol-type eclipsing binary in the Catalina Surveys
Periodic Variable Star Catalogue. We have identified NSV 1907 as an ultraviolet
(UV) bright source using measurements from the GALEX space telescope and
detected obvious out-of-eclipse variability in archival photometric data from
the Catalina Sky Survey, which instigated a closer examination of the object. A
spectrum and extensive multicolour photometric observations were acquired, from
which we deduce that NSV 1907 is a deeply eclipsing, nova-like cataclysmic
variable. Apart from the orbital variations (deep eclipses with a period of P ~
6.63 hours), changes in mean brightness and irregular short-term variability
(flickering) were observed. The presence of a secondary minimum at phase phi ~
0.5 was established, which indicates a significant contribution of the
companion star to the optical flux of the system. We find possible evidence for
sinusoidal variations with a period of P ~ 4.2 d, which we interpret as the
nodal precession period of the accretion disc. No outbursts or VY Scl-like
drops in brightness were detected either by the CSS or during our photometric
monitoring. Because of its spectral characteristics and the observed
variability pattern, we propose NSV 1907 as a new moderately bright long-period
SW Sextantis star. Further photometric and spectroscopic observations are
encouraged.


title: The ABC of Higher-Spin AdS/CFT

abstract:
  In recent literature one-loop tests of the higher-spin AdS$_{d+1}$/CFT$_d$
correspondences were carried out. Here we extend these results to a more
general set of theories in $d>2$. First, we consider the Type B higher spin
theories, which have been conjectured to be dual to CFTs consisting of the
singlet sector of $N$ free fermion fields. In addition to the case of $N$ Dirac
fermions, we carefully study the projections to Weyl, Majorana, symplectic, and
Majorana-Weyl fermions in the dimensions where they exist. Second, we explore
theories involving elements of both Type A and Type B theories, which we call
Type AB. Their spectrum includes fields of every half-integer spin, and they
are expected to be related to the $U(N)/O(N)$ singlet sector of the CFT of $N$
free complex/real scalar and fermionic fields. Finally, we explore the Type C
theories, which have been conjectured to be dual to the CFTs of $p$-form gauge
fields, where $p=\frac d 2 -1$. In most cases we find that the free energies at
$O(N^0)$ either vanish or give contributions proportional to the free-energy of
a single free field in the conjectured dual CFT. Interpreting these
non-vanishing values as shifts of the bulk coupling constant $G_N\sim 1/(N-k)$,
we find the values $k=-1, -1/2, 0, 1/2, 1, 2$. Exceptions to this rule are the
Type B and AB theories in odd $d$; for them we find a mismatch between the bulk
and boundary free energies that has a simple structure, but does not follow
from a simple shift of the bulk coupling constant.


title: On the theory of quantum quenches in near-critical systems

abstract:
  The theory of quantum quenches in near-critical one-dimensional systems
formulated in [J. Phys. A 47 (2014) 402001] yields analytic predictions for the
dynamics, unveils a qualitative difference between non-interacting and
interacting systems, with undamped oscillations of one-point functions
occurring only in the latter case, and explains the presence and role of
different time scales. Here we examine additional aspects, determining in
particular the relaxation value of one-point functions for small quenches. For
a class of quenches we relate this value to the scaling dimensions of the
operators. We argue that the $E_8$ spectrum of the Ising chain can be more
accessible through a quench than at equilibrium, while for a quench of the
plane anisotropy in the XYZ chain we obtain that the one-point function of the
quench operator switches from damped to undamped oscillations at $\Delta=1/2$.


title:
Tridiagonal pairs of $q$-Racah type, the Bockting operator $\psi$, and
  $L$-operators for $U_q(L({\mathfrak{sl}}_2))$

abstract:
  We describe the Bockting operator $\psi$ for a tridiagonal pair of $q$-Racah
type, in terms of a certain $L$-operator for the quantum loop algebra
$U_q(L({\mathfrak {sl}}_2))$.


title: On Graphs Representable by Pattern-Avoiding Words

abstract:
  In this paper we study graphs defined by pattern-avoiding words.
Word-representable graphs have been studied extensively following their
introduction in 2000 and are the subject of a book published by Kitaev in 2015.
Recently there has been interest in studying graphs represented by
pattern-avoiding words. In particular, in 2016, Gao, Kitaev, and Zhang
investigated 132-representable graphs, that is, word-representable graphs that
can be represented by a word which avoids the pattern 132. They proved that all
132- representable graphs are circle graphs and provided examples and
properties of 132-representable graphs. They posed several questions, some of
which we answer in this paper.
  One of our main results is that not all circle graphs are 132-representable,
thus proving that 132-representable graphs are a proper subset of circle
graphs, a question that was left open in the paper by Gao et al. We show that
123-representable graphs are also a proper subset of circle graphs, and are
different from 132-representable graphs. We also study graphs represented by
pattern-avoiding 2-uniform words, that is, words in which every letter appears
exactly twice.


title:
Grain-resolved kinetics and rotation during grain growth of
  nanocrystalline Aluminium by molecular dynamics

abstract:
  Grain growth in nanocrystalline Al was studied by means of molecular dynamics
simulations. The novelty of this study results from the utilization of an
algorithm to resolve per-grain kinetics and orientation change from molecular
dynamics data sets. To this aim, a highly efficient algorithm for the
identification and reconstruction of crystallites from molecular dynamics data
sets of FCC materials was developed. This method is capable of calculating
specific attributes of grains, namely, volume, center of mass, average
orientation and orientation spread. In addition, it provides a mapping method
to track grains during time-row data sets. In the present contribution, we
describe and validate the algorithm, which is then used to analyze grain growth
in polycrystalline Al with a weak texture. For the conditions tested, the
algorithm was able to find all of the input orientations and reconstruct the
grains according to their crystallographic orientation. With the help of the
developed algorithms, we studied grain growth kinetics and grain rotation. The
results of the simulations showed slightly slowed-down kinetics in particular
in the initial stages of grain growth and marginal rotation of the grains.


title:
Mitosis Detection in Intestinal Crypt Images with Hough Forest and
  Conditional Random Fields

abstract:
  Intestinal enteroendocrine cells secrete hormones that are vital for the
regulation of glucose metabolism but their differentiation from intestinal stem
cells is not fully understood. Asymmetric stem cell divisions have been linked
to intestinal stem cell homeostasis and secretory fate commitment. We monitored
cell divisions using 4D live cell imaging of cultured intestinal crypts to
characterize division modes by means of measurable features such as orientation
or shape. A statistical analysis of these measurements requires annotation of
mitosis events, which is currently a tedious and time-consuming task that has
to be performed manually. To assist data processing, we developed a learning
based method to automatically detect mitosis events. The method contains a
dual-phase framework for joint detection of dividing cells (mothers) and their
progeny (daughters). In the first phase we detect mother and daughters
independently using Hough Forest whilst in the second phase we associate mother
and daughters by modelling their joint probability as Conditional Random Field
(CRF). The method has been evaluated on 32 movies and has achieved an AUC of
72%, which can be used in conjunction with manual correction and dramatically
speed up the processing pipeline.


title:
"Sampling"' as a Baseline Optimizer for Search-based Software
  Engineering

abstract:
  Increasingly, Software Engineering (SE) researchers use search-based
optimization techniques to solve SE problems with multiple conflicting
objectives. These techniques often apply CPU-intensive evolutionary algorithms
to explore generations of mutations to a population of candidate solutions. An
alternative approach, proposed in this paper, is to start with a very large
population and sample down to just the better solutions. We call this method
"SWAY", short for "the sampling way". Sway is very simple to implement and, in
studies with various software engineering models, this sampling approach was
found to be competitive with corresponding state-of-the-art evolutionary
algorithms while requiring far less computation cost. Considering the
simplicity and effectiveness of Sway, we, therefore, propose this approach as a
baseline method for search-based software engineering models, especially for
models that are very slow to execute.


title: Multiresolution network models

abstract:
  Many existing statistical and machine learning tools for social network
analysis focus on a single level of analysis. Methods designed for clustering
optimize a global partition of the graph, whereas projection based approaches
(e.g. the latent space model in the statistics literature) represent in rich
detail the roles of individuals. Many pertinent questions in sociology and
economics, however, span multiple scales of analysis. Further, many questions
involve comparisons across disconnected graphs that will, inevitably be of
different sizes, either due to missing data or the inherent heterogeneity in
real-world networks. We propose a class of network models that represent
network structure on multiple scales and facilitate comparison across graphs
with different numbers of individuals. These models differentially invest
modeling effort within subgraphs of high density, often termed communities,
while maintaining a parsimonious structure between said subgraphs. We show that
our model class is projective, highlighting an ongoing discussion in the social
network modeling literature on the dependence of inference paradigms on the
size of the observed graph. We illustrate the utility of our method using data
on household relations from Karnataka, India.


title: Interacting with Massive Behavioral Data

abstract:
  In this short paper, we propose the split-diffuse (SD) algorithm that takes
the output of an existing word embedding algorithm, and distributes the data
points uniformly across the visualization space. The result improves the
perceivability and the interactability by the human.
  We apply the SD algorithm to analyze the user behavior through access logs
within the cyber security domain. The result, named the topic grids, is a set
of grids on various topics generated from the logs. On the same set of grids,
different behavioral metrics can be shown on different targets over different
periods of time, to provide visualization and interaction to the human experts.
  Analysis, investigation, and other types of interaction can be performed on
the topic grids more efficiently than on the output of existing dimension
reduction methods. In addition to the cyber security domain, the topic grids
can be further applied to other domains like e-commerce, credit card
transaction, customer service to analyze the behavior in a large scale.


title: What Is the Source of Quiet Sun Transition Region Emission?

abstract:
  Dating back to the first observations of the on-disk corona, there has been a
qualitative link between the photosphere's magnetic network and enhanced
transition-temperature plasma emission. These observations led to the
development of a general model that describes emission structures through the
partitioning of the atmospheric volume with different magnetic loop geometries
that exhibit different energetic equilibria. Does the internetwork produce
transition-temperature emission? What fraction of network flux connects to the
corona? How does quiet sun emission compare with low-activity Sun-like stars?
In this work, we revisit the canonical model of the quiet sun, with
high-resolution observations from IRIS and HMI in hand, to address those
questions. We use over 900 deep exposures of Si IV 1393A from IRIS along with
nearly simultaneous HMI magnetograms to quantify the correlation between
transition-temperature emission structures and magnetic field concentrations
through a number of novel statistics. Our observational results are coupled
with analysis of the Bifrost MHD model and a large-scale potential field model.
Our results paint a complex portrait of the quiet sun. We measure an emission
signature in the distant internetwork that cannot be attributed to network
contribution. We find that the dimmest regions of emission are not linked to
the local vertical magnetic field. Using the MHD simulation, we categorize the
emission contribution from cool mid-altitude loops and high-altitude coronal
loops and discuss the potential emission contribution of spicules. Our results
provide new constraints on the coupled solar atmosphere so that we can build on
our understanding of how dynamic thermal and magnetic structures generate the
observed phenomena in the transition region.


title: Rapid social connectivity

abstract:
  Given a graph $G=(V,E)$, consider Poisson($ |V|$) walkers performing
independent lazy simple random walks on $G$ simultaneously, where the initial
position of each walker is chosen independently with probability proportional
to the degrees. When two walkers visit the same vertex at the same time they
are declared to be acquainted. The social connectivity time $\mathrm{SC}(G)$ is
defined as the first time in which there is a path of acquaintances between
every pair of walkers. It is shown that when the average degree of $G$ is $d$,
with high probability \[ c\log |V| \le \mathrm{SC}(G) \le C d^{1+5 \cdot 1_{G
\text{ is not regular}} } \log^3 |V|.\] When $G$ is regular the lower bound is
improved to $\mathrm{SC}(G) \ge \log |V| -6 \log \log |V| $, with high
probability.
  We determine $\mathrm{SC}(G)$ up to a constant factor in the cases that $G$
is an expander and when it is the $n$-cycle.


title:
Critical mass for infinite-time aggregation in a chemotaxis model with
  indirect signal production

abstract:
  We study the Neumann initial-boundary problem for the chemotaxis system $$
\left\{\begin{array}{ll} u_t= \Delta u - \nabla \cdot (u\nabla v), & x\in
\Omega, \, t>0, 0=\Delta v - \mu(t)+w, & x\in \Omega, \, t>0, \tau w_t + \delta
w = u, & x\in \Omega, \, t>0, \end{array} \right. \qquad \qquad (\star) $$ in
the unit disk $\Omega:=B_1(0)\subset \R^2$, where $\delta\ge 0$ and $\tau>0$
are given parameters and $\mu(t):=\mint_\Omega w(x,t)dx$, $t>0$. It is shown
that this problem exhibits a novel type of critical mass phenomenon with regard
to the formation of singularities, which drastically differs from the
well-known threshold property of the classical Keller-Segel system, as obtained
upon formally taking $\tau\to 0$, in that it refers to blow-up in infinite time
rather than in finite time: Specifically, it is first proved that for any
sufficiently regular nonnegative initial data $u_0$ and $w_0$, ($\star$)
possesses a unique global classical solution. In particular, this shows that in
sharp contrast to classical Keller-Segel-type systems reflecting immediate
signal secretion by the cells themselves, the indirect mechanism of signal
production in ($\star$) entirely rules out any occurrence of blow-up in finite
time. However, within the framework of radially symmetric solutions it is next
proved that whenever $\delta>0$ and $\io u_0<8\pi\delta$, the solution remains
uniformly bounded, whereas for any choice of $\delta\ge 0$ and $m>8\pi\delta$,
one can find initial data such that $\io u_0=m$, and such that for the
corresponding solution we have \bas \|u(\cdot,t)\|_{L^\infty(\Omega)} \to
\infty \qquad \mbox{as} t\to\infty.


title: A dynamic system characterization of road network node models

abstract:
  The propagation of traffic congestion along roads is a commonplace nonlinear
phenomenon. When many roads are connected in a network, congestion can spill
from one road to others as drivers queue to enter a congested road, creating
further nonlinearities in the network dynamics. This paper considers the node
model problem, which refers to methods for solving for cross-flows when roads
meet at a junction. We present a simple hybrid dynamic system that, given a
macroscopic snapshot of the roads entering and exiting a node, intuitively
models the node's throughflows over time. This dynamic system produces
solutions to the node model problem that are equal to those produced by many
popular node models without intuitive physical meanings. We also show how the
earlier node models can be rederived as executions of our dynamic system. The
intuitive physical description supplied by our system provides a base for
control of the road junction system dynamics, as well as the emergent network
dynamics.


title:
New Evidence for a Low-Temperature Magnetic Ground State in
  Double-Perovskite Iridates with Ir5+(5d4) Ions

abstract:
  We report an unusual magnetic ground state in single-crystal,
double-perovskite Ba2YIrO6 and Sr doped Ba2YIrO6 with Ir5+(5d4) ions.
Long-range magnetic order below 1.7 K is confirmed by DC magnetization, AC
magnetic susceptibility and heat capacity measurements. The observed magnetic
order is extraordinarily delicate and cannot be explained in terms of either a
low-spin S=1 state, or a singlet Jeff=0 state imposed by the spin-orbit
interactions (SOI). Alternatively, the magnetic ground state appears consistent
with a SOI that competes with comparable Hund's rule coupling and inherently
large electron hopping, which cannot stabilize the singlet Jeff=0 ground state.
However, this picture is controversial, and conflicting magnetic behavior for
these materials is reported in both experimental and theoretical studies, which
highlights the intricate interplay of interactions that determine the ground
state of materials with strong SOI.


title: Large Scale Behavioral Analytics via Topical Interaction

abstract:
  We propose the split-diffuse (SD) algorithm that takes the output of an
existing dimension reduction algorithm, and distributes the data points
uniformly across the visualization space. The result, called the topic grids,
is a set of grids on various topics which are generated from the free-form text
content of any domain of interest. The topic grids efficiently utilizes the
visualization space to provide visual summaries for massive data. Topical
analysis, comparison and interaction can be performed on the topic grids in a
more perceivable way.


title: Dynamical modeling of pulsed two-photon interference

abstract:
  Single-photon sources are at the heart of quantum-optical networks, with
their uniquely quantum emission and phenomenon of two-photon interference
allowing for the generation and transfer of nonclassical states. Although a few
analytical methods have been briefly investigated for describing pulsed
single-photon sources, these methods apply only to either perfectly ideal or at
least extremely idealized sources. Here, we present the first complete picture
of pulsed single-photon sources by elaborating how to numerically and fully
characterize non-ideal single-photon sources operating in a pulsed regime. In
order to achieve this result, we make the connection between quantum
Monte--Carlo simulations, experimental characterizations, and an extended form
of the quantum regression theorem. We elaborate on how an ideal pulsed
single-photon source is connected to its photocount distribution and its
measured degree of second- and first-order optical coherence. By doing so, we
provide a description of the relationship between instantaneous source
correlations and the typical experimental interferometers (Hanbury-Brown and
Twiss, Hong-Ou-Mandel, and Mach-Zehnder) used to characterize such sources.
Then, we use these techniques to explore several prototypical quantum systems
and their non-ideal behaviors. As an example numerical result, we show that for
the most popular single-photon source---a resonantly excited two-level
system---its error probability is directly related to its excitation pulse
length. We believe that the intuition gained from these representative systems
and characters can be used to interpret future results with more complicated
source Hamiltonians and behaviors. Finally, we have thoroughly documented our
simulation methods with contributions to the Quantum Optics Toolbox in Python
(QuTiP) in order to make our work easily accessible to other scientists and
engineers.


title:
On the contravariant of homogeneous forms arising from isolated
  hypersurface singularities

abstract:
  Let ${\mathcal Q}_n^d$ be the vector space of homogeneous forms of degree
$d\ge 3$ on ${\mathbb C}^n$, with $n\ge 2$. The object of our study is the map
$\Phi$, introduced in earlier articles by J. Alper, M. Eastwood and the author,
that assigns to every form for which the discriminant $\Delta$ does not vanish
the so-called associated form lying in the space ${\mathcal Q}_n^{n(d-2)*}$.
This map is a morphism from the affine variety $X_n^d:=\{f\in{\mathcal
Q}_n^d:\Delta(f)\ne 0\}$ to the affine space ${\mathcal Q}_n^{n(d-2)*}$.
Letting $p$ be the smallest integer for which the product $\Delta^p\Phi$
extends to a morphism from ${\mathcal Q}_n^d$ to ${\mathcal Q}_n^{n(d-2)*}$,
one observes that the extended map defines a contravariant of forms in
${\mathcal Q}_n^d$. In the present paper we obtain upper bounds for $p$ thus
providing estimates for the contravariant's degree.


title: Isotropic curve flows on $R^{n+1, n}$

abstract:
  Let $R^{n+1, n}$ be the vector space $R^{2n+1}$ equipped with the bilinear
form $(X,Y)=X^t C_n Y$ of index $n$, where $C_n= \sum_{i=1}^{2n+1} (-1)^{n+i-1}
e_{i, 2n+2-i}$. A smooth $\gamma: R\to R^{n+1,n}$ is {\it isotropic} if
$\gamma, \gamma_x, \ldots, \gamma_x^{(2n)}$ are linearly independent and the
span of $\gamma, \ldots, \gamma_x^{(n-1)}$ is isotropic. Given an isotropic
curve, we show that there is a unique up to translation parameter such that
$(\gamma_x^{(n)}, \gamma_x^{(n)})=1$ (we call such parameter the isotropic
parameter) and there also exists a natural moving frame. In this paper, we
consider two sequences of curve flows on the space of isotropic curves
parametrized by isotropic parameter. We show that differential invariants of
these isotropic curves satisfy Drinfeld-Sokolov's KdV type soliton hierarchies
associated to the affine Kac-Moody algebra $\hat B_n^{(1)}$ and $\hat
A_{2n}^{(2)}$ Then we use techniques from soliton theory to construct
bi-Hamiltonian structure, conservation laws, Backlund transformations and
permutability formulas for these curve flows.


title: Baryons in the unquenched quark model

abstract:
  In this contribution, we present the unquenched quark model as an extension
of the constituent quark model that includes the effects of sea quarks via a
$^{3}P_{0}$ quark-antiquark pair-creation mechanism. Particular attention is
paid to the spin and flavor content of the proton, magnetic moments and $\beta$
decays of octet baryons.


title:
Global analysis of Expectation Maximization for mixtures of two
  Gaussians

abstract:
  Expectation Maximization (EM) is among the most popular algorithms for
estimating parameters of statistical models. However, EM, which is an iterative
algorithm based on the maximum likelihood principle, is generally only
guaranteed to find stationary points of the likelihood objective, and these
points may be far from any maximizer. This article addresses this disconnect
between the statistical principles behind EM and its algorithmic properties.
Specifically, it provides a global analysis of EM for specific models in which
the observations comprise an i.i.d. sample from a mixture of two Gaussians.
This is achieved by (i) studying the sequence of parameters from idealized
execution of EM in the infinite sample limit, and fully characterizing the
limit points of the sequence in terms of the initial parameters; and then (ii)
based on this convergence analysis, establishing statistical consistency (or
lack thereof) for the actual sequence of parameters produced by EM.


title: Geometric symmetries in light nuclei

abstract:
  The algebraic cluster model is is applied to study cluster states in the
nuclei 12C and 16O. The observed level sequences can be understood in terms of
the underlying discrete symmetry that characterizes the geometrical
configuration of the alpha-particles, i.e. an equilateral triangle for 12C, and
a regular tetrahedron for 16O. The structure of rotational bands provides a
fingerprint of the underlying geometrical configuration of alpha-particles.


title:
Resource Allocation for Machine-to-Machine Communications with Unmanned
  Aerial Vehicles

abstract:
  In this paper, a novel framework for power-efficient, cluster-based
machine-to-machine (M2M) communications is proposed. In the studied model, a
number of unmanned aerial vehicles (UAVs) are used as aerial base stations to
collect data from the cluster heads (CHs) of a set of M2M clusters. To minimize
the CHs' transmit power while satisfying the rate requirements of M2M devices,
an optimal scheduling and resource allocation mechanism for CH-UAV
communications is proposed. First, using the queue rate stability concept, the
minimum number of UAVs as well as the dwelling time that each UAV must spend
for servicing the CHs are computed. Next, the optimal resource allocation for
the CH-UAV communication links is determined such that M2M devices rate
requirements are satisfied with a minimum transmit power. Simulation results
show that, as the packet transmission probability of machines increases, the
minimum number of UAVs required to guarantee the queue rate stability of CHs
will also significantly increase. Our results also show that, compared to a
case with pre-deployed terrestrial base stations, the average transmit power of
CHs will decrease by 68% when UAVs are used.


title:
Unusually High and Anisotropic Thermal Conductivity in Amorphous Silicon
  Nanostructures

abstract:
  Amorphous Si (a-Si) nanostructures are ubiquitous in numerous electronic and
optoelectronic devices. Amorphous materials are considered to possess the lower
limit to the thermal conductivity (k), which is ~1 W/m-K for a-Si. However,
recent work suggested that k of micro-thick a-Si films can be greater than 3
W/m-K, which is contributed by propagating vibrational modes, referred to as
"propagons". However, precise determination of k in a-Si has been elusive.
Here, we used novel structures of a-Si nanotubes and suspended a-Si films that
enabled precise in-plane k measurement within a wide thickness range of 5 nm to
1.7 um. We showed unexpectedly high in plane k in a-Si nanostructures, reaching
~3.0 and 5.3 W/m-K at 100 nm and 1.7 um, respectively. Furthermore, the
measured in plane k is significantly higher than the cross-plane k on the same
films. This usually high and anisotropic k in the amorphous Si nanostructures
manifests the surprising broad propaganda mean free path distribution, which is
found to range from 10 nm to 10 um, in the disordered and atomically isotropic
structure. This result provides an unambiguous answer to the century-old
problem regarding the mean free path distribution of propagons and also shed
light on the design and performance of numerous a-Si based electronic and
optoelectronics devices.


title:
Performance Guaranteed Approximation Algorithm for Minimum $k$-Connected
  $m$-Fold Dominating Set

abstract:
  To achieve an efficient routing in a wireless sensor network, connected
dominating set (CDS) is used as virtual backbone. A fault-tolerant virtual
backbone can be modeled as a $(k,m)$-CDS. For a connected graph $G=(V,E)$ and
two fixed integers $k$ and $m$, a node set $C\subseteq V$ is a $(k,m)$-CDS of
$G$ if every node in $V\setminus C$ has at least $m$ neighbors in $C$, and the
subgraph of $G$ induced by $C$ is $k$-connected. Previous to this work,
approximation algorithms with guaranteed performance ratio in a general graph
were know only for $k\leq 3$. This paper makes a significant progress by
presenting a $(2k-1)\alpha_0$ approximation algorithm for general $k$ and $m$
with $m\geq k$, where $\alpha_0$ is the performance ratio for the minimum CDS
problem. Using currently best known ratio for $\alpha_0$, our algorithm has
performance ratio $O(\ln\Delta)$, where $\Delta$ is the maximum degree of the
graph.


title: Random sets and intersections

abstract:
  The following class of problems arose out of vain attempts to show that the
Pascal's triangle adic transformation has trivial spectrum. Partition a set of
size $N$ into sets of size $S \equiv S(N)$ (ignoring leftovers). What is the
likelihood that a set of size $K \equiv K(N)$ will intersect each set in the
partition in at least $R \equiv R(N)$ members (as $N$ increases)? Via
elementary techniques and under reasonable hypotheses, we obtain an easy-to-use
formula. Although different from the corresponding minimum problem for balls
and bins (with $m = K$ balls and $n = N/S$ bins), under modest constraints, the
asymptotic probabilities are the same.


title: Learning Temporal Dependence from Time-Series Data with Latent Variables

abstract:
  We consider the setting where a collection of time series, modeled as random
processes, evolve in a causal manner, and one is interested in learning the
graph governing the relationships of these processes. A special case of wide
interest and applicability is the setting where the noise is Gaussian and
relationships are Markov and linear. We study this setting with two additional
features: firstly, each random process has a hidden (latent) state, which we
use to model the internal memory possessed by the variables (similar to hidden
Markov models). Secondly, each variable can depend on its latent memory state
through a random lag (rather than a fixed lag), thus modeling memory recall
with differing lags at distinct times. Under this setting, we develop an
estimator and prove that under a genericity assumption, the parameters of the
model can be learned consistently. We also propose a practical adaption of this
estimator, which demonstrates significant performance gains in both synthetic
and real-world datasets.


title: Class Invariants: Concepts, Problems, Solutions

abstract:
  Class invariants are both a core concept of object-oriented programming and
the source of the two key open OO verification problems: furtive access (from
callbacks) and reference leak. Existing approaches force on programmers an
unacceptable annotation burden. This article explains invariants and solves
both problems modularly through the O-rule, defining fundamental OO semantics,
and the inhibition rule, using information hiding to remove harmful reference
leaks. It also introduces the concept of "object tribe" as a basis for other
possible approaches.
  For all readers: this article is long because it includes a tutorial, covers
many examples and dispels misconceptions. To understand the key ideas and
results, however, the first two pages suffice.
  For non-experts in verification: all concepts are explained; anyone with a
basic understanding of object-oriented programming can understand the
discussion.
  For experts: the main limitation of this work is that it is a paper proposal
(no soundness proof, no implementation). It addresses, however, the known
problems with class invariants, solving such examples as linked lists and
Observer, through a simple theory and without any of the following: ownership;
separation logic; universe types; object wrapping and unwrapping; semantic
collaboration, observer specifications; history invariants; "inc" and "coop"
constructs; friendship construct; non-modular reasoning. More generally, it
involves no new language construct and no new programmer annotations.


title: Reconstructing parton densities at large fractional momenta

abstract:
  Parton distribution functions (PDFs) are nonperturbative objects defined by
nonlocal light-cone correlations. They cannot be computed directly from Quantum
Chromodynamics (QCD). Using a standard lattice QCD approach, it is possible to
compute moments of PDFs, which are matrix elements of local operators.
Recently, an alternative approach has been proposed, based on the introduction
of quasi-parton distribution functions (quasi-PDFs), which are matrix elements
of equal-time spatial correlations and hence calculable on lattice. Quasi-PDFs
approach standard PDFs in the limit of very large longitudinal proton momenta
$P^z$. This limit is not attainable in lattice simulations, and quasi-PDFs fail
to reproduce PDFs at high fractional longitudinal momenta. In this paper, we
propose a method to improve the reconstruction of PDFs by combining information
from quasi-PDFs and from the Mellin moments of regular PDFs. We test our method
using the diquark spectator model for up and down valence distributions of both
unpolarized and helicity PDFs. In the future, the method can be used to produce
PDFs entirely based on lattice QCD results.


title: Learning to generalize to new compositions in image understanding

abstract:
  Recurrent neural networks have recently been used for learning to describe
images using natural language. However, it has been observed that these models
generalize poorly to scenes that were not observed during training, possibly
depending too strongly on the statistics of the text in the training data. Here
we propose to describe images using short structured representations, aiming to
capture the crux of a description. These structured representations allow us to
tease-out and evaluate separately two types of generalization: standard
generalization to new images with similar scenes, and generalization to new
combinations of known entities. We compare two learning approaches on the
MS-COCO dataset: a state-of-the-art recurrent network based on an LSTM (Show,
Attend and Tell), and a simple structured prediction model on top of a deep
network. We find that the structured model generalizes to new compositions
substantially better than the LSTM, ~7 times the accuracy of predicting
structured representations. By providing a concrete method to quantify
generalization for unseen combinations, we argue that structured
representations and compositional splits are a useful benchmark for image
captioning, and advocate compositional models that capture linguistic and
visual structure.


title:
Schr\"odinger maximal function estimates via the pseudoconformal
  transformation

abstract:
  We present an alternative way to recover the recent result from \cite{LR}
using the pseudoconformal transformation.


title: Batched Stochastic Gradient Descent with Weighted Sampling

abstract:
  We analyze a batched variant of Stochastic Gradient Descent (SGD) with
weighted sampling distribution for smooth and non-smooth objective functions.
We show that by distributing the batches computationally, a significant speedup
in the convergence rate is provably possible compared to either batched
sampling or weighted sampling alone. We propose several computationally
efficient schemes to approximate the optimal weights, and compute proposed
sampling distributions explicitly for the least squares and hinge loss
problems. We show both analytically and experimentally that substantial gains
can be obtained.


title:
Lidov-Kozai Cycles with Gravitational Radiation: Merging Black Holes in
  Isolated Triple Systems

abstract:
  We show that a black-hole binary with an external companion can undergo
Lidov-Kozai cycles that cause a close pericenter passage, leading to a rapid
merger due to gravitational-wave emission. This scenario occurs most often for
systems in which the companion has mass comparable to the reduced mass of the
binary and the companion orbit has semi-major axis within a factor of $\sim 10$
of the binary semi-major axis. Using a simple population-synthesis model and
3-body simulations, we estimate the rate of mergers in triple black hole
systems in the field to be about six per Gpc$^3$ per year in the absence of
natal kicks during black hole formation. This value is within the low end of
the 90\% credible interval for the total black-hole black-hole merger rate
inferred from the current LIGO results. There are many uncertainties in these
calculations, the largest of which is the unknown distribution of natal kicks.
Even modest natal kicks of $40\mbox{km s}^{-1}$ will reduce the merger rate by
a factor of 40. A few percent of these systems will have eccentricity greater
than 0.999 when they first enter the frequency band detectable by aLIGO (above
10 Hz).


title: An automorphic variant of the Deligne conjecture

abstract:
  In this paper we introduce an automorphic variant of the Deligne conjecture
for tensor product of two motives over a quadratic imaginary field. On one
hand, we define some motivic periods and rewrite the Deligne conjecture in
terms of these periods. On the other hand, we define the automorphic analogue
of these motivic periods and then give a purely automorphic variant of the
Deligne conjecture. At last, we introduce some known results of this
automorphic variant.


title: Remarks on Quantum Probability Backflow

abstract:
  It is known that for a non-relativistic quantum particle traveling freely on
the $x$-axis, the positional probability can flow in the opposite direction to
the particle's velocity. The maximum possible amount of such backflow that can
occur over any time interval has been determined previously as the largest
positive eigenvalue of a certain hermitian observable, with the value
$0.0384517\dots$, or about $4\%$ of the total probability on the line. The
eigenvalue problem is now considered numerically in the more general case of
states with momentum restricted to the range $p_0<p<\infty$, for any given
value $p_0$. It is found that the maximum possible backflow decreases
monotonically, but never reaches $0$, as $p_0$ increases through positive
values; and it increases monotonically, but never reaches $1$, as $p_0$
decreases through negative values. Both of these effects are non-classical. The
results allow a simple interpretation of the classical limit, as an effective
value of Planck's constant goes to zero and probability backflow becomes
impossible.


title:
An abelian quotient of the symplectic derivation Lie algebra of the free
  Lie algebra

abstract:
  We construct an abelian quotient of the symplectic derivation Lie algebra
$\mathfrak{h}_{g,1}$ of the free Lie algebra generated by the fundamental
representation of $\mathrm{Sp}(2g,\mathbb{Q})$. More specifically, we show that
the weight $12$ part of the abelianization of $\mathfrak{h}_{g,1}$ is
$1$-dimensional for $g \ge 8$. The computation is done with the aid of
computers.


title: Tunneling induced spin dynamics in a quantum dot-lead hybrid system

abstract:
  Semiconductor quantum dots (QDs) offer a platform to explore the physics of
quantum electronics including spins. Electron spins in QDs are considered good
candidates for quantum bits in quantum information processing, and spin control
and readout have been established down to a single electron level. We use these
techniques to explore spin dynamics in a hybrid system, namely a QD coupled to
a two dimensional electronic reservoir. The proximity of the lead results in
relaxation dynamics of both charge and spin, the mechanism of which is revealed
by comparing the charge and spin signal. For example, higher order charge
tunneling events can be monitored by observing the spin. We expect these
results to stimulate further exploration of spin dynamics in QD-lead hybrid
systems and expand the possibilities for controlled spin manipulations.


title:
Elementary polytopes with high lift-and-project ranks for strong
  positive semidefinite operators

abstract:
  We consider operators acting on convex subsets of the unit hypercube. These
operators are used in constructing convex relaxations of combinatorial
optimization problems presented as a 0,1 integer programming problem or a 0,1
polynomial optimization problem. Our focus is mostly on operators that, when
expressed as a lift-and-project operator, involve the use of semidefiniteness
constraints in the lifted space, including operators due to Lasserre and
variants of the Sherali--Adams and Bienstock--Zuckerberg operators. We study
the performance of these semidefinite-optimization-based lift-and-project
operators on some elementary polytopes --- hypercubes that are chipped (at
least one vertex of the hypercube removed by intersection with a closed
halfspace) or cropped (all $2^n$ vertices of the hypercube removed by
intersection with $2^n$ closed halfspaces) to varying degrees of severity
$\rho$. We prove bounds on $\rho$ where these operators would perform badly on
the aforementioned examples. We also show that the integrality gap of the
chipped hypercube is invariant under the application of several
lift-and-project operators of varying strengths.


title: Results from a search for dark matter in the complete LUX exposure

abstract:
  We report constraints on spin-independent weakly interacting massive particle
(WIMP)-nucleon scattering using a 3.35e4 kg-day exposure of the Large
Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber
with 250 kg of active mass is operated at the Sanford Underground Research
Facility under Lead, South Dakota (USA). With roughly fourfold improvement in
sensitivity for high WIMP masses relative to our previous results, this search
yields no evidence of WIMP nuclear recoils. At a WIMP mass of 50 GeV/c^2,
WIMP-nucleon spin-independent cross sections above 2.2e-46 cm^2 are excluded at
the 90% confidence level. When combined with the previously reported LUX
exposure, this exclusion strengthens to 1.1e-46 cm^2 at 50 GeV/c^2.

categories: astro-ph.CO astro-ph.IM hep-ex physics.ins-det


title:
Casimir force of two-component Bose-Einstein condensates confined by a
  parallel plate geometry

abstract:
  Using field theory we calculate the Casimir energy and Casimir force of
two-component Bose-Einstein condensates restricted between two parallel plates,
in which Dirichlet and periodic boundary conditions applied. Our results show
that, in one-loop approximation, the Casimir force equals to summation of the
one of each component and it is vanishing in some cases: (i) inter-distance
between two plates becomes large enough; (ii) intraspecies interaction is zero;
(iii) interspecies interaction is full strong segregation.


title:
Real-time geopotentiometry with synchronously linked optical lattice
  clocks

abstract:
  According to the Einstein's theory of relativity, the passage of time changes
in a gravitational field. On earth, raising a clock by one centimetre increases
its tick rate by 1.1 parts in 10$^{18}$, enabling optical clocks to perform
precision geodesy. Here, we demonstrate geopotentiometry by determining the
height difference of master and slave clocks separated by 15 km with
uncertainty of 5 cm. The subharmonic of the master clock is delivered through a
telecom fibre to phase-lock and synchronously interrogate the slave clock. This
protocol rejects laser noise in the comparison of two clocks, which improves
the stability of measuring the gravitational red shift. Such phase-coherently
operated clocks facilitate proposals for linking clocks and interferometers.
Over half a year, 11 measurements determine the fractional frequency difference
between the two clocks to be $1,652.9(5.9)\times 10^{-18}$, or a height
difference of 1,516(5) cm, consistent with an independent measurement by
levelling and gravimetry. Our system is as a building block of an internet of
clocks, consisting of a master and a number of slave clocks, which will provide
"quantum benchmarks" that are height references with dynamic response.


title:
Enumeration of holomorphic cylinders in log Calabi-Yau surfaces. II.
  Positivity, integrality and the gluing formula

abstract:
  We prove three fundamental properties of counting holomorphic cylinders in
log Calabi-Yau surfaces: positivity, integrality and the gluing formula.
Positivity and integrality assert that the numbers of cylinders, defined via
virtual techniques, are in fact nonnegative integers. The gluing formula
roughly says that cylinders can be glued together to form longer cylinders, and
the number of longer cylinders equals the product of the numbers of shorter
cylinders. Our approach uses Berkovich geometry, tropical geometry, deformation
theory and the ideas in the proof of associativity relations of Gromov-Witten
invariants by Maxim Kontsevich. These three properties provide an evidence for
a conjectural relation between counting cylinders and the broken lines of
Gross-Hacking-Keel.


title: Testing Unateness of Real-Valued Functions

abstract:
  We give a unateness tester for functions of the form $f:[n]^d\rightarrow R$,
where $n,d\in \mathbb{N}$ and $R\subseteq \mathbb{R}$ with query complexity
$O(\frac{d\log (\max(d,n))}{\epsilon})$. Previously known unateness testers
work only for Boolean functions over the domain $\{0,1\}^d$. We show that every
unateness tester for real-valued functions over hypergrid has query complexity
$\Omega(\min\{d, |R|^2\})$. Consequently, our tester is nearly optimal for
real-valued functions over $\{0,1\}^d$. We also prove that every nonadaptive,
1-sided error unateness tester for Boolean functions needs
$\Omega(\sqrt{d}/\epsilon)$ queries. Previously, no lower bounds for testing
unateness were known.


title: A hot gaseous galaxy halo candidate with Mg X absorption

abstract:
  The hot gas in galaxy halos may account for a significant fraction of missing
baryons in galaxies, and some of these gases can be traced by high ionization
absorption systems in QSO UV spectra. Using high S/N ratio $ HST$/COS spectra,
we discovered a high ionization state system at $z=1.1912$ in the sightline
toward \object{LBQS 1435-0134}, and two-components absorption lines are matched
for Mg X, Ne VIII, Ne VI, O VI, Ne V, O V, Ne IV, O IV, N IV, O III, and H I.
Mg X, detected for the first time ($5.8 \sigma$), is a particularly direct
tracer of hot galactic halos, as its peak ion fraction occurs near
$10^{6.1}\rm~ K$, about the temperature of a virialized hot galaxy halo of mass
$\sim 0.5 M^*$. With Mg X and NeVIII, a photoionization model cannot reproduce
the observed column densities with path lengths of galaxy halos. For
collisional ionization models, one or two temperature models do not produce
acceptable fits, but a three temperature model or a power law model can produce
the observed results. In the power law model, ${\rm d}N/{\rm d}T = 10^{4.4\pm
2.2-[Z/X]} T^{1.55\pm 0.41}$ with temperatures in the range $10^{4.39\pm0.13}
{\rm~K} < T < 10^{6.04\pm0.05}~ {\rm K}$, the total hydrogen column density is
$8.2 \times 10^{19} (0.3Z_{\odot}/Z) \rm~ cm^{-2}$ and the positive power law
index indicates most of the mass is at the high temperature end. We suggest
that this absorption system is a hot volume-filled galaxy halo rather than
interaction layers between the hot halo and cool clouds. The temperature
dependence of the column density is likely due to the local mixture of multiple
phase gases.


title:
Semilinear nonlocal elliptic equations with critical and supercritical
  exponents

abstract:
  We study the problem \begin{eqnarray*} (-\Delta)^s u &=& u^p - u^q
\quad\text{in }\quad \mathbb{R}^N, u &\in& \dot{H}^s(\mathbb{R}^N)\cap
L^{q+1}(\mathbb{R}^N), u&>0& \quad\text{in}\quad\mathbb{R}^N, \end{eqnarray*}
where $s\in(0,1)$ is a fixed parameter, $(-\Delta)^s$ is the fractional
laplacian in $\mathbb{R}^N$, $q>p\geq \frac{N+2s}{N-2s}$ and $N>2s$. For every
$s\in(0,1)$, we establish regularity results of solutions of above equation
(whenever solution exists) and we show that every solution is a classical
solution. Next, we derive certain decay estimate of solutions and the gradient
of solutions at infinity for all $s\in(0,1)$. Using those decay estimates, we
prove Pohozaev type identity in $\mathbb{R}^N$ and show that the above problem
does not have any solution when $p=\frac{N+2s}{N-2s}$. We also discuss radial
symmetry and decreasing property of the solution and prove that when
$p>\frac{N+2s}{N-2s}$, the above problem admits a solution. Moreover, if we
consider the above equation in a bounded domain with Dirichlet boundary
condition, we prove that it admits a solution for every $p\geq
\frac{N+2s}{N-2s}$ and every solution is a classical solution.


title:
Modeling the Solar Wind at the Ulysses, Voyager, and New Horizons
  Spacecraft

abstract:
  The outer heliosphere is a dynamic region shaped largely by the interaction
between the solar wind and the interstellar medium. While interplanetary
magnetic field and plasma observations by the Voyager spacecraft have
significantly improved our understanding of this vast region, modeling the
outer heliosphere still remains a challenge. We simulate the three-dimensional,
time-dependent solar wind flow from 1 to 80 astronomical units (AU), where the
solar wind is assumed to be supersonic, using a two-fluid model in which
protons and interstellar neutral hydrogen atoms are treated as separate fluids.
We use 1-day averages of the solar wind parameters from the OMNI data set as
inner boundary conditions to reproduce time-dependent effects in a simplified
manner which involves interpolation in both space and time. Our model generally
agrees with Ulysses data in the inner heliosphere and Voyager data in the outer
heliosphere. Ultimately, we present the model solar wind parameters extracted
along the trajectory of New Horizons spacecraft. We compare our results with in
situ plasma data taken between 11 and 33 AU and at the closest approach to
Pluto on July 14, 2015.


title: On the structure of certain valued fields

abstract:
  In this article, we study the structure of finitely ramified mixed
characteristic valued fields. For any two complete discrete valued fields $K_1$
and $K_2$ of mixed characteristic with perfect residue fields, we show that if
the $n$-th residue rings are isomorphic for each $n\ge 1$, then $K_1$ and $K_2$
are isometric and isomorphic. More generally, for $n_1\ge 1$, there is $n_2$
depending only on the ramification indices of $K_1$ and $K_2$ such that any
homomorphism from the $n_1$-th residue ring of $K_1$ to the $n_2$-th residue
ring of $K_2$ can be lifted to a homomorphism between the valuation rings.
Moreover, we get a functor from the category of certain principal Artinian
local rings of length $n$ to the category of certain complete discrete
valuation rings of mixed characteristic with perfect residue fields, which
naturally generalizes the functorial property of unramified complete discrete
valuation rings. Our lifting result improves Basarab's relative completeness
theorem for finitely ramified henselian valued fields, which solves a question
posed by Basarab, in the case of perfect residue fields.


title:
Testing Einstein's weak equivalence principle with a 0.4-nanosecond
  giant pulse of the Crab pulsar

abstract:
  Einstein's weak equivalence principle (EEP) can be tested through the arrival
time delay between photons with different frequencies. Assuming that the
arrival time delay is solely caused by the gravitational potential of the Milky
Way, we show that a "nano-shot" giant pulse with a time delay between energies
corrected for all known effects, e.g. $\Delta t<0.4~\rm{ns}$, from the Crab
pulsar poses a new upper limit on the deviation from EEP, i.e. $\Delta\gamma <
(0.6-1.8)\times 10^{-15}$. This result provides the hitherto most stringent
constraint on the EEP, improving by at least 2 to 3 orders of magnitude from
the previous results based on fast radio bursts.


title:
TopoMan: Global Network Visibility in the Presence of Middleboxes (A
  Graybox Approach)

abstract:
  Software Defined Networks (SDN) provide vital benefits to network
administrators by offering global visibility and network-wide control over the
switching infrastructure of the network. It is rather much difficult to obtain
the same benefits in the presence of middleboxes (MBs), due to (i) lack of a
proper topology discovery mechanism in environments with a mix of forwarding
devices and middleboxes. (ii) lack of generic APIs to abstract and gain control
on these rigid and heterogeneous third-party middleboxes (iii) lack of a
generic network infrastructure framework to monitor and verify any specific
device or path connectivity status in the network. These limitations make
automation of network operations such as, network-wide monitoring, policy
enforcement and rule-placement much difficult to handle. Hence, there is a
greater urge even from middlebox vendors, to better handle the control and
visibility aspects of the network in presence of middleboxes.
  In this paper, we propose a Unified network infrastructure framework for
gaining global network visibility, by discovering the network topology in the
presence of middleboxes, along with a framework to support the end-to-end path
connectivity verification, independent of SDN. We have also addressed security
aspects and provided necessary APIs to support our framework.


title:
Long-Time Behavior of Solutions to the Derivative Nonlinear
  Schr\"{o}dinger Equation for Soliton-Free Initial Data

abstract:
  The large-time behavior of solutions to the derivative nonlinear
Schr\"{o}dinger equation is established for initial conditions in some weighted
Sobolev spaces under the assumption that the initial conditions do not support
solitons. Our approach uses the inverse scattering setting and the nonlinear
steepest descent method of Deift and Zhou as recast by Dieng and McLaughlin.


title: Polarization-selective out-coupling of whispering gallery modes

abstract:
  Whispering gallery mode (WGM) resonators are an important building block for
linear, nonlinear and quantum optical experiments. In such experiments,
independent control of coupling rates to different modes can lead to improved
conversion efficiencies and greater flexibility in generation of non-classical
states based on parametric down conversion. In this work, we introduce a scheme
which enables selective out-coupling of WGMs belonging to a specific
polarization family, while the orthogonally polarized modes remain largely
unperturbed. Our technique utilizes material birefringence in both the
resonator and coupler such that a negative (positive) birefringence allows
selective coupling to TE (TM) polarized WGMs. We formulate a new coupling
condition suitable for describing the case where the refractive indices of the
resonator and the coupler are almost the same, from which we derive the
criterion for polarization-selective coupling. We experimentally demonstrate
our proposed method using a lithium niobate disk resonator coupled to a lithium
niobate prism, where we show a 22dB suppression of coupling to TM modes
relative to TE modes.


title: The evolutionary status of dense cores in the NGC 1333 IRAS 4 region

abstract:
  Protostellar evolution, following the formation of the protostar is becoming
reasonably well characterized, but the evolution from a prestellar core to a
protostar is not well known, although the first hydrostatic core (FHSC) must be
a pivotal step. NGC 1333 IRAS 4C is a potentially very young object, that we
directly compare with the nearby Class 0 IRAS 4A and IRAS 4B. Observational
constraints are provided by spectral imaging from the JCMT Spectral Legacy
Survey (330-373 GHz) and continuum and line observations from CARMA. We present
integrated intensity and velocity maps of several species, including CO, H2CO
and CH3OH. The velocity of an observed outflow, the degree of CO depletion, the
deuteration of DCO+/HCO+ and gas kinetic temperatures are observational
signatures that we present. We report differences between the three sources in
four aspects: a) the kinetic temperature is much lower towards IRAS 4C, b) the
line profiles of the detected species show strong outflow activity towards IRAS
4A and IRAS 4B but not towards IRAS 4C, c) the HCN/HNC is < 1 towards IRAS 4C,
which confirms the cold nature of the source, d) the degree of CO depletion and
the deuteration are the lowest towards the warmest of the sources, IRAS 4B.
IRAS 4C seems to be in a different evolutionary state than the IRAS 4A and IRAS
4B sources. We can probably exclude the FHSC stage due to the relatively low
Lsmm/Lbol (~6\%) and we investigate the earliest accretion phase of Class 0
stage and the transition between Class 0 to Class I. Our results do not show a
consistent scenario for either case, with the major issue being the absence of
outflow activity and the cold nature of IRAS 4C. The number of FHSC candidates
in Perseus is ~10 times higher than current models predict, which suggests that
the lifespan of these objects is greater than 1000 years, possibly due to an
accretion rate lower than 4x10^-5 msun/yr.


title: Re-embedding a 1-Plane Graph into a Straight-line Drawing in Linear Time

abstract:
  Thomassen characterized some 1-plane embedding as the forbidden configuration
such that a given 1-plane embedding of a graph is drawable in straight-lines if
and only if it does not contain the configuration [C. Thomassen, Rectilinear
drawings of graphs, J. Graph Theory, 10(3), 335-341, 1988].
  In this paper, we characterize some 1-plane embedding as the forbidden
configuration such that a given 1-plane embedding of a graph can be re-embedded
into a straight-line drawable 1-plane embedding of the same graph if and only
if it does not contain the configuration. Re-embedding of a 1-plane embedding
preserves the same set of pairs of crossing edges.
  We give a linear-time algorithm for finding a straight-line drawable 1-plane
re-embedding or the forbidden configuration.


title:
A universal lower bound on the free energy cost of molecular
  measurements

abstract:
  The living cell uses a variety of molecular receptors to read and process
chemical signals that vary in space and time. We model the dynamics of such
molecular level measurements as Markov processes in steady state, with a
coupling between the receptor and the signal. We prove exactly that, when the
the signal dynamics is not perturbed by the receptors, the free energy consumed
by the measurement process is lower bounded by a quantity proportional to the
mutual information. Our result is completely independent of the receptor
architecture and dependent on signal properties alone, and therefore holds as a
general principle for molecular information processing.


title:
Spatio-temporal Aware Non-negative Component Representation for Action
  Recognition

abstract:
  This paper presents a novel mid-level representation for action recognition,
named spatio-temporal aware non-negative component representation (STANNCR).
The proposed STANNCR is based on action component and incorporates the
spatial-temporal information. We first introduce a spatial-temporal
distribution vector (STDV) to model the distributions of local feature
locations in a compact and discriminative manner. Then we employ non-negative
matrix factorization (NMF) to learn the action components and encode the video
samples. The action component considers the correlations of visual words, which
effectively bridge the sematic gap in action recognition. To incorporate the
spatial-temporal cues for final representation, the STDV is used as the part of
graph regularization for NMF. The fusion of spatial-temporal information makes
the STANNCR more discriminative, and our fusion manner is more compact than
traditional method of concatenating vectors. The proposed approach is
extensively evaluated on three public datasets. The experimental results
demonstrate the effectiveness of STANNCR for action recognition.


title:
Effect of spatial discretization of energy on detonation wave
  propagation

abstract:
  Detonation propagation in the limit of highly spatially discretized energy
sources is investigated. The model of this problem begins with a medium
consisting of a calorically perfect gas with a prescribed energy release per
unit mass. The energy release is collected into sheet-like sources that are now
embedded in an inert gas that fills the spaces between them. The release of
energy in the first sheet results in a planar blast wave that propagates to the
next source, which is triggered after a prescribed delay, generating a new
blast, and so forth. The resulting wave dynamics as the front passes through
hundreds of such sources is computationally simulated by numerically solving
the governing one-dimensional Euler equations in the lab-fixed reference frame.
The average wave speed for each simulation is measured once the wave
propagation has reached a quasi-periodic solution. Velocities in excess of the
CJ speed are found as the sources are made increasingly discrete, with the
deviation above CJ being as great as $15\%$. The total energy release, delay
time, and whether the sources remain lab-fixed or are convected with the flow
do not have a significant influence on the deviation of the average wave speed
away from CJ. Such continuous waves can also be shown to have a time-averaged
structure consistent with the classical ZND structure of a detonation. In the
limit of highly discrete sources, temporal averaging of the wave structure
shows that the effective sonic surface does not correspond to an equilibrium
state. The average state of the flow leaving the wave in this case does
eventually reach the equilibrium Hugoniot, but only after the effective sonic
surface has been crossed. Thus, the super-CJ waves observed in the limit of
highly discretized sources can be understood as weak detonations due to the
non-equilibrium state at the effective sonic surface.


title:
Destination-aided Wireless Power Transfer in Energy-limited Cognitive
  Relay Systems

abstract:
  This paper considers an energy-limited cognitive relay network where a
secondary transmitter (ST) assists to forward the traffic from a primary
transmitter (PT) to a primary receiver (PR), in exchange for serving its own
secondary receiver (SR) in the same frequency. The multiple-antenna ST is
assumed to be energy-constrained and powered by both information flow from
source (PT) and dedicated energy streams from destinations (PR and SR), which
is called destination-aided wireless power transfer (DWPT) scheme. Then, the
relay processing matrix, cognitive beamforming vector and power splitter are
jointly de- signed to maximize the rate of secondary users under the energy
causality constraint and the constraint that the demanded rate of primary users
is satisfied. For the perfect channel information state (CSI) case, by adopting
semi-definite relax (SDR) technique and Charnes-Cooper transformation, the
global optimal solution is given. To reduce the complexity, matrix
decomposition, zero forcing (ZF) scheme, and dual method are jointly employed
to derive a suboptimal solution. For the imperfect CSI case, S- procedure is
used to transform the worst-case robust problem into a tractable semi-definite
program (SDP). Simulation results reveal that our proposed DWPT scheme is
greatly preferred for both perfect and imperfect CSI cases when ST is close to
PR/SR.


title: Conformal Vector Fields of a Class of Finsler Spaces II

abstract:
  In this paper, we first give two fundamental principles under a technique to
characterize conformal vector fields of $(\alpha,\beta)$ spaces to be
homothetic and determine the local structure of those homothetic fields. Then
we use the principles to study conformal vector fields of some classes of
$(\alpha,\beta)$ spaces under certain curvature conditions. Besides, we
construct a family of non-homothetic conformal vector fields on a family of
locally projectively Randers spaces.


title:
Towards efficient orbital-dependent density functionals for weak and
  strong correlation

abstract:
  We present a new paradigm for the design of exchange-correlation functionals
in density-functional theory. Electron pairs are correlated explicitly by means
of the recently developed second order Bethe-Goldstone equation (BGE2)
approach. Here we propose a screened BGE2 (sBGE2) variant that efficiently
regulates the coupling of a given electron pair. sBGE2 correctly dissociates
H$_2$ and H$_2^+$, a problem that has been regarded as a great challenge in
density-functional theory for a long time. The sBGE2 functional is then taken
as a building block for an orbital-dependent functional, termed ZRPS, which is
a natural extension of the PBE0 hybrid functional. While worsening the good
performance of sBGE2 in H$_2$ and H$_2^{+}$, ZRPS yields a remarkable and
consistent improvement over other density functionals across various chemical
environments from weak to strong correlation.


title:
Effects of proton angular momentum alignment on the two-shears-like
  mechanism in $^{101}$Pd

abstract:
  The recently observed possible antimagnetic rotation band in $^{101}$Pd is
investigated by the cranked shell model with pairing correlations treated by a
particle-number conserving method, in which the blocking effects are taken into
account exactly. The experimental moments of inertia and reduced $B(E2)$
transition probabilities and their variations with the rotational frequency
$\omega$ are well reproduced. By analyzing the $\omega$-dependence of the
occupation probability of each cranked Nilsson orbital near the Fermi surface
and the contributions of valence orbitals in each major shell to the total
angular momentum alignment, the upbending mechanism of $\nu h_{11/2}$ in
$^{101}$Pd is understood clearly. The proton angular momentum alignment and its
influence on the two-shears-like mechanism are also discussed.


title:
CISER: An Amoebiasis inspired Model for Epidemic Message Propagation in
  DTN

abstract:
  Delay Tolerant Networks (DTNs) are sparse mobile networks, which experiences
frequent disruptions in connectivity among nodes. Usually, DTN follows
store-carry-and forward mechanism for message forwarding, in which a node store
and carry the message until it finds an appropriate relay node to forward
further in the network. So, The efficiency of DTN routing protocol relies on
the intelligent selection of a relay node from a set of encountered nodes.
Although there are plenty of DTN routing schemes proposed in the literature
based on different strategies of relay selection, there are not many
mathematical models proposed to study the behavior of message forwarding in
DTN. In this paper, we have proposed a novel epidemic model, called as CISER
model, for message propagation in DTN, based on Amoebiasis disease propagation
in human population. The proposed CISER model is an extension of SIR epidemic
model with additional states to represent the resource constrained behavior of
nodes in DTN. Experimental results using both synthetic and real-world traces
show that the proposed model improves the routing performance metrics, such as
delivery ratio, overhead ratio and delivery delay compared to SIR model.


title:
Investigation of the high-spin rotational properties of the proton
  emitter $^{113}$Cs using a particle-number conserving method

abstract:
  The recently observed two high-spin rotational bands in the proton emitter
$^{113}$Cs are investigated using the cranked shell model with pairing
correlations treated by a particle-number conserving method, in which the Pauli
blocking effects are taken into account exactly. By using the configuration
assignments of band 1 ($\pi 3/2^+[422], \alpha = -1/2$) and band 2 ($\pi
1/2^+[420], \alpha = 1/2$), the experimental moments of inertia and
quasiparticle alignments can be well reproduced by the present calculations,
which in turn strongly support these configuration assignments. Furthermore, by
analyzing the occupation probability $n_\mu$ of each cranked Nilsson level near
the Fermi surface and the contribution of each orbital to the angular momentum
alignments, the backbending mechanism of these two bands is also investigated.


title:
Transceiver Design for Cooperative Non-Orthogonal Multiple Access
  Systems with Wireless Energy Transfer

abstract:
  In this paper, an energy harvesting (EH) based cooperative non-orthogonal
multiple access (NOMA) system is considered, where node S simultaneously sends
independent signals to a stronger node R and a weaker node D. We focus on the
scenario that the direct link between S and D is too weak to meet the quality
of service (QoS) of D. Based on the NOMA principle, node R, the stronger user,
has prior knowledge about the information of the weaker user, node D. To
satisfy the targeted rate of D, R also serves as an EH decode-and-forward (DF)
relay to forward the traffic from S to D. In the sense of equivalent cognitive
radio concept, node R viewed as a secondary user assists to boost the
performance of D, in exchange for receiving its own information from S.
Specifically, transmitter beamforming design, power splitting ratio
optimization and receiver filter design to maximize node R rate are studied
with the predefined QoS constraint of D and the power constraint of S. Since
the problem is non-convex, we propose an iterative approach to solve it.
Moreover, to reduce the computational complexity, a zero- forcing (ZF) based
solution is also presented. Simulation results demonstrate that, both two
proposed schemes have better performance than the direction transmission.


title: Wide-Band Spectra of Giant Radio Pulses from the Crab Pulsar

abstract:
  We present the results of the simultaneous observation of the giant radio
pulses (GRPs) from the Crab pulsar at 0.3, 1.6, 2.2, 6.7, and 8.4 GHz with four
telescopes in Japan. We obtain 3194 and 272 GRPs occurring at the main pulse
and the interpulse phases, respectively. A few GRPs detected at both 0.3 and
8.4 GHz are the most wide-band samples ever reported. In the frequency range
from 0.3 to 2.2 GHz, we find that about 70\% or more of the GRP spectra are
consistent with single power laws and the spectral indices of them are
distributed from $-4$ to $-1$. We also find that a significant number of GRPs
have such a hard spectral index (approximately $-1$) that the fluence at 0.3
GHz is below the detection limit ("dim-hard" GRPs). Stacking light curves of
such dim-hard GRPs at 0.3 GHz, we detect consistent enhancement compared to the
off-GRP light curve. Our samples show apparent correlations between the
fluences and the spectral hardness, which indicates that more energetic GRPs
tend to show softer spectra. Our comprehensive studies on the GRP spectra are
useful materials to verify the GRP model of fast radio bursts in future
observations.


title: An analytical model of prominence dynamics

abstract:
  Solar prominences are magnetic structures incarcerating cool and dense gas in
an otherwise hot solar corona. Prominences can be categorized as quiescent and
active. Their origin and the presence of cool gas (~$10^4$K) within the hot
(~$10^6$K) solar corona remains poorly understood. The structure and dynamics
of solar prominences was investigated in a large number of observational and
theoretical (both analytical and numerical) studies. In this paper, an analytic
model of quiescent solar prominence is developed and used to demonstrate that
the prominence velocity increases exponentially, which means that some gas
falls downward towards the solar surface, and that Alfven waves are naturally
present in the solar prominences. These theoretical predictions are consistent
with the current observational data of solar quiescent prominences.


title:
New Limits on the Photon Mass with Radio Pulsars in the Magellanic
  Clouds

abstract:
  A conservative constraint on the rest mass of the photon can be estimated
under the assumption that the frequency dependence of dispersion from
astronomical sources is mainly contributed by the nonzero photon mass effect.
Photon mass limits have been earlier set through the optical emissions of the
Crab Nebula pulsar, but we prove that these limits can be significantly
improved with the dispersion measure (DM) measurements of radio pulsars in the
Large and Small Magellanic Clouds. The combination of DM measurements of
pulsars and distances of the Magellanic Clouds provide a strict upper limit on
the photon mass as low as $m_{\gamma} \leq2.0\times10^{-45}~\rm{g}$, which is
at least four orders of magnitude smaller than the constraint from the Crab
Nebula pulsar. Although our limit is not as tight as the current best result
($\sim10^{-47}~\rm{g}$) from a fast radio burst (FRB 150418) at a cosmological
distance, the cosmological origin of FRB 150418 remains under debate; and our
limit can reach the same high precision of FRB 150418 when it has an
extragalactic origin ($\sim10^{-45}~\rm{g}$).


title: Minimal model program for excellent surfaces

abstract:
  We establish the minimal model program for log canonical and Q-factorial
surfaces over excellent base schemes.


title: Plasma dynamics of a laser filamentation-guided spark

abstract:
  We investigate experimentally the plasma dynamics of a centimeter-scale,
laser filamentation-guided spark discharge. Using electrical and optical
diagnostics to study monopolar discharges with varying current pulses we show
that plasma decay is dominated by free electron recombination if the current
decay time is shorter than the recombination characteristic time. In the
opposite case, the plasma electron density closely follows the current
evolution. We demonstrate that this criterion holds true in the case of damped
AC sparks, and that alternative current is the best option to achieve a long
plasma lifetime for a given peak current.


title:
Geometric Frustration of Colloidal Dimers on a Honeycomb Magnetic
  Lattice

abstract:
  We study the phase behaviour and the collective dynamics of interacting
paramagnetic colloids assembled above a honeycomb lattice of triangular shaped
magnetic minima. A frustrated colloidal molecular crystal is realized when
filling these potential minima with exactly two particles per pinning site.
External in-plane rotating fields are used to anneal the system into different
phases, including long range ordered stripes, random fully packed loops,
labyrinth and disordered states. At higher amplitude of the annealing field,
the dimer lattice displays a two step melting transition where the initially
immobile dimers perform first localized rotations and later break up by
exchanging particles across consecutive lattice minima.


title:
Passive Fingerprinting of SCADA in Critical Infrastructure Network
  without Deep Packet Inspection

abstract:
  We present the first technique of passive fingerprinting for Supervisory
Control And Data Acquisition (SCADA) networks without Deep Packet Inspection
(DPI) and experience on real environment. Unlike existing work, our method does
not rely on the functions of a specific product or DPI of the SCADA protocol.
Our inference method, which is based on the intrinsic characteristics of SCADA,
first identifies the network port used for the SCADA protocol, then
consecutively infers the field devices and master server. We evaluated the
effectiveness of our method using two network traces collected from a real
environment for a month and a half, three days from different CI respectively.
This confirmed the ability of our method to capture most of the SCADA with high
F-score nearly 1, except for HMIs connected to master server, and demonstrated
the practical applicability of the method.


title: The crossing number of the cone of a graph

abstract:
  Motivated by a problem asked by Richter and by the long standing Harary-Hill
conjecture, we study the relation between the crossing number of a graph $G$
and the crossing number of its cone $CG$, the graph obtained from $G$ by adding
a new vertex adjacent to all the vertices in $G$. Simple examples show that the
difference $cr(CG)-cr(G)$ can be arbitrarily large for any fixed $k=cr(G)$. In
this work, we are interested in finding the smallest possible difference, that
is, for each non-negative integer $k$, find the smallest $f(k)$ for which there
exists a graph with crossing number at least $k$ and cone with crossing number
$f(k)$. For small values of $k$, we give exact values of $f(k)$ when the
problem is restricted to simple graphs, and show that $f(k)=k+\Theta (\sqrt
{k})$ when multiple edges are allowed.


title:
Regularization and the small-ball method II: complexity dependent error
  rates

abstract:
  For a convex class of functions $F$, a regularization functions $\Psi(\cdot)$
and given the random data $(X_i, Y_i)_{i=1}^N$, we study estimation properties
of regularization procedures of the form \begin{equation*}
  \hat f \in {\rm argmin}_{f\in
  F}\Big(\frac{1}{N}\sum_{i=1}^N\big(Y_i-f(X_i)\big)^2+\lambda \Psi(f)\Big)
\end{equation*} for some well chosen regularization parameter $\lambda$.
  We obtain bounds on the $L_2$ estimation error rate that depend on the
complexity of the "true model" $F^*:=\{f\in F: \Psi(f)\leq\Psi(f^*)\}$, where
$f^*\in {\rm argmin}_{f\in F}\mathbb{E}(Y-f(X))^2$ and the $(X_i,Y_i)$'s are
independent and distributed as $(X,Y)$. Our estimate holds under weak
stochastic assumptions -- one of which being a small-ball condition satisfied
by $F$ -- and for rather flexible choices of regularization functions
$\Psi(\cdot)$. Moreover, the result holds in the learning theory framework: we
do not assume any a-priori connection between the output $Y$ and the input $X$.
  As a proof of concept, we apply our general estimation bound to various
choices of $\Psi$, for example, the $\ell_p$ and $S_p$-norms (for $p\geq1$),
weak-$\ell_p$, atomic norms, max-norm and SLOPE. In many cases, the estimation
rate almost coincides with the minimax rate in the class $F^*$.


title:
Footprints of the weak s-process in the carbon-enhanced metal-poor star
  ET0097

abstract:
  Historically, the weak s-process contribution to metal-poor stars is thought
to be extremely small, due to the effect of the secondary-like nature of the
neutron source 22Ne(a;n)25Mg in massive stars, which means that metal-poor weak
s-process stars could not be found. ET0097 is the first observed
carbon-enhanced metal-poor (CEMP) star in the Sculptor dwarf spheroidal galaxy.
Because C is enriched and the elements heavier than Ba are not overabundant,
ET0097 can be classified as a CEMP-no star. However, this star shows
overabundances of lighter n-capture elements (i.e., Sr, Y and Zr). In this
work, having adopted the abundance decomposition approach, we investigate the
astrophysical origins of the elements in ET0097. We find that the light
elements and iron-peak elements (from O to Zn) of the star mainly originate
from the primary process of massive stars and the heavier n-capture elements
(heavier than Ba) mainly come from the main r-process. However, the lighter
n-capture elements such as Sr, Y and Zr should mainly come from the primary
weak s-process. The contributed fractions of the primary weak s-process to the
Sr, Y and Zr abundances of ET0097 are about 82%, 84% and 58% respectively,
suggesting that the CEMP star ET0097 should have the footprints of the weak
s-process. The derived result should be a significant evidence that the weak
s-process elements can be produced in metal-poor massive stars.


title:
Cosmological expansion and contraction from Pauli exclusion principle in
  $M0$-branes

abstract:
  We show that the Pauli exclusion principle in a system of $M0$-branes can
give rise to the expansion and contraction of the universe which is located on
an $M3$-brane. We start with a system of $M0$-branes with high symmetry, which
join mutually and form pairs of $M1$-anti-$M1$-branes. The resulting symmetry
breaking creates gauge fields that live on the $M1$-branes and play the role of
graviton tensor modes, which induce an attractive force between the $M1$ and
anti-$M1$ branes. Consequently, the gauge fields that live on the $M1$-branes,
and the scalar fields which are attached symmetrically to all parts of these
branes, decay to fermions that attach anti-symmetrically to the upper and lower
parts of the branes, and hence the Pauli exclusion principle emerges. By
closing $M1$-branes mutually, the curvatures produced by parallel spins will be
different from the curvatures produced by anti-parallel spins, and this leads
to an inequality between the number of degrees of freedom on the boundary
surface and the number of degrees of freedom in the bulk region. This behavior
is inherited in the $M3$-brane on which the universe is located, and hence this
leads to the emergence of the universe expansion and contraction. In this
sense, the Pauli exclusion principle rules the cosmic dynamics.


title: Quantum metrology in coarsened measurement reference

abstract:
  We investigate the role of coarsened measurement reference in quantum
metrology. Coarsened measurement reference comes from the coarsened reference
time and basis. When the measurement based on one common reference basis, the
disadvantage can be removed by symmetry. Due to the coarsened reference basis,
entangled states can not perform better than product states for large number of
probe particles. Given a finite uncertainty of the coarsened reference basis,
the optimal number of probe particle is obtained in estimating phase. Finally,
we prove that the maximally entangled state always achieves better precision
under the case of non-Markovian dephasing than that under the case of Markovian
dephasing. The product state is more resistant to interference of the coarsened
reference time than the entangled state.