title:
High-Roller Impact: A Large Generalized Game Model of Parimutuel
  Wagering

abstract:
  How do large-scale participants in parimutuel wagering events affect the
house and ordinary bettors? A standard narrative suggests that they may
temporarily benefit the former at the expense of the latter. To approach this
problem, we begin by developing a model based on the theory of large
generalized games. Constrained only by their budgets, a continuum of diffuse
(ordinary) players and a single atomic (large-scale) player simultaneously
wager to maximize their expected profits according to their individual beliefs.
Our main theoretical result gives necessary and sufficient conditions for the
existence and uniqueness of a pure-strategy Nash equilibrium. Using this
framework, we analyze our question in concrete scenarios. First, we study a
situation in which both predicted effects are observed. Neither is always
observed in our remaining examples, suggesting the need for a more nuanced view
of large-scale participants.


title: $q$-Quasiadditive Functions

abstract:
  In this paper, we introduce the notion of $q$-quasiadditivity of arithmetic
functions, as well as the related concept of $q$-quasimultiplicativity, which
generalises strong $q$-additivity and -multiplicativity, respectively. We show
that there are many natural examples for these concepts, which are
characterised by functional equations of the form $f(q^{k+r}a + b) = f(a) +
f(b)$ or $f(q^{k+r}a + b) = f(a) f(b)$ for all $b < q^k$ and a fixed parameter
$r$. In addition to some elementary properties of $q$-quasiadditive and
$q$-quasimultiplicative functions, we prove characterisations of
$q$-quasiadditivity and $q$-quasimultiplicativity for the special class of
$q$-regular functions. The final main result provides a general central limit
theorem that includes both classical and new examples as corollaries.


title:
Continuous-wave, single-frequency 229 nm laser source for laser cooling
  of cadmium atoms

abstract:
  Continuous-wave output at 229 nm for the application of laser cooling of Cd
atoms was generated by the 4th harmonic using two successive second harmonic
generation stages. Employing a single-frequency optically pumped semiconductor
laser as a fundamental source, 0.56 W of output at 229 nm was observed with a
10-mm long, Brewster-cut BBO crystal in an external cavity with 1.62 W of 458
nm input. Conversion efficiency from 458 nm to 229 nm was more than 34%. By
applying a tapered amplifier as a fundamental source, we demonstrated
magneto-optical trapping of all stable Cd isotopes including isotopes
$^{111}$Cd and $^{113}$Cd, which are applicable to optical lattice clocks.


title:
Effects of the high-momentum tail of nucleon momentum distribution on
  the isospin-sensitive observables

abstract:
  Based on the Isospin-dependent transport model Boltzmann-Uehling-Uhlenbeck
(IBUU), effects of the high momentum tail (HMT) of nucleon momentum
distribution in colliding nuclei on some isospin-sensitive observables are
studied in the semi-central $^{197}\rm {Au}+^{197}\rm {Au}$ reactions at
incident beam energy of 400 MeV/nucleon. It is found that the nucleon
transverse flow, the difference of neutron and proton transverse flows, the
nucleon elliptic flow and free neutron to proton ratio are all less sensitive
to the HMT, while the isospin-sensitive nucleon elliptic flow difference is
clearly affected by the HMT. Except at very high kinetic energies, the kinetic
energy distributions of $\pi^{-}$, $\pi^{+}$ and charged pion ratio
$\pi^{-}/\pi^{+}$ are all sensitive to the HMT.


title: Volterra Series Based Time-domain Macro-modeling of Nonlinear Circuits

abstract:
  Volterra series representation is a powerful mathematical model for nonlinear
circuits. However, the difficulties in determining higher-order Volterra
kernels limited its broader applications. In this work, a systematic approach
that enables a convenient extraction of Volterra kernels from X-parameters is
presented. A concise and general representation of the output response due to
arbitrary number of input tones is given. The relationship between Volterra
kernels and X-parameters is explicitly formulated. An efficient frequency sweep
scheme and an output frequency indexing scheme are provide. The least square
linear regression method is employed to separate different orders of Volterra
kernels at the same frequency, which leads to the obtained Volterra kernels
complete. The proposed Volterra series representation based on X-parameters is
further validated for time domain verification. The proposed method is
systematic and general-purpose. It paves the way for time domain simulation
with X-parameters and constitutes a powerful supplement to existing blackbox
macro-modeling methods for nonlinear circuits.


title: Top Production at the Tevatron: The Antiproton Awakens

abstract:
  A long time ago, at a laboratory far, far away, the Fermilab Tevatron
collided protons and antiprotons at $\sqrt{s} = 1.96$ TeV. The CDF and D0
experiments each recorded datasets of about 10 fb$^{-1}$. As such experiments
may never be repeated, these are unique datasets that allow for unique
measurements. This presentation describes recent results from the two
experiments on top-quark production rates, spin orientations, and production
asymmetries, which are all probes of the $p\bar{p}$ initial state.


title:
Causal production of the electromagnetic energy flux and role of the
  negative energies in Blandford-Znajek process

abstract:
  Blandford-Znajek process, the steady electromagnetic energy extraction from a
rotating black hole (BH), is widely believed to work for driving relativistic
jets in active galactic nuclei, gamma-ray bursts and Galactic microquasars,
although it is still under debate how the Poynting flux is causally produced
and how the rotational energy of the BH is reduced. We generically discuss the
Kerr BH magnetosphere filled with a collisionless plasma screening the electric
field along the magnetic field, extending the arguments of Komissarov and our
previous paper, and propose a new picture for resolving the issues. For the
magnetic field lines threading the equatorial plane in the ergosphere, we find
that the inflow of particles with negative energy as measured in the coordinate
basis is generated near that plane as a feedback from the Poynting flux
production, which appears to be a similar process to the mechanical Penrose
process. For the field lines threading the event horizon, we first show that
the concept of the steady inflow of negative electromagnetic energy is not
physically essential, partly because the sign of the electromagnetic energy
density depends on the coordinates. Then we build an analytical toy model of a
time-dependent process both in the Boyer-Lindquist and Kerr-Schild coordinate
systems in which the force-free plasma injected continuously is filling a
vacuum, and suggest that the structure of the steady outward Poynting flux is
causally constructed by the displacement current and the cross-field current at
the in-going boundary between the plasma and the vacuum. In the steady state,
the Poynting flux is maintained without any electromagnetic source.


title: Does Antibiotic Resistance Evolve in Hospitals?

abstract:
  Nosocomial outbreaks of bacteria are well-documented. Based on these
incidents, and the heavy usage of antibiotics in hospitals, it has been assumed
that antibiotic resistance evolves in hospital environments. To test this
assumption, we studied resistance phenotypes of bacteria collected from patient
isolates at a community hospital over a 2.5-year period. A graphical model
analysis shows no association between resistance and patient information other
than time of arrival. This allows us to focus on time course data.
  We introduce a Hospital Transmission Model, based on negative binomial delay.
Our main contribution is a statistical hypothesis test called the Nosocomial
Evolution of Resistance Detector (NERD). It calculates the significance of
resistance trends occurring in a hospital. It can inform hospital staff about
the effects of various practices and interventions, can help detect clonal
outbreaks, and is available as an R-package.
  We applied the NERD method to each of the 16 antibiotics in the study via 16
hypothesis tests. For 13 of the antibiotics, we found that the hospital
environment had no significant effect upon the evolution of resistance; the
hospital is merely a piece of the larger picture. The p-values obtained for the
other three antibiotics (Cefepime, Ceftazidime and Gentamicin) indicate that
particular care should be taken in hospital practices with these antibiotics.
One of the three, Ceftazidime, was significant after accounting for multiple
hypotheses, indicating a trend of decreased resistance for this drug.


title: Learning Representations for Counterfactual Inference

abstract:
  Observational studies are rising in importance due to the widespread
accumulation of data in fields such as healthcare, education, employment and
ecology. We consider the task of answering counterfactual questions such as,
"Would this patient have lower blood sugar had she received a different
medication?". We propose a new algorithmic framework for counterfactual
inference which brings together ideas from domain adaptation and representation
learning. In addition to a theoretical justification, we perform an empirical
comparison with previous approaches to causal inference from observational
data. Our deep learning algorithm significantly outperforms the previous
state-of-the-art.


title:
Subspace Perspective on Canonical Correlation Analysis: Dimension
  Reduction and Minimax Rates

abstract:
  Canonical correlation analysis (CCA) is a fundamental statistical tool for
exploring the correlation structure between two sets of random variables. In
this paper, motivated by recent success of applying CCA to learn low
dimensional representations of high dimensional objects, we propose to quantify
the estimation loss of CCA by the excess prediction loss defined through a
prediction-after-dimension-reduction framework. Such framework suggests viewing
CCA estimation as estimating the subspaces spanned by the canonical variates.
Interestedly, the proposed error metrics derived from the excess prediction
loss turn out to be closely related to the principal angles between the
subspaces spanned by the population and sample canonical variates respectively.
  We characterize the non-asymptotic minimax rates under the proposed metrics,
especially the dependency of the minimax rates on the key quantities including
the dimensions, the condition number of the covariance matrices, the canonical
correlations and the eigen-gap, with minimal assumptions on the joint
covariance matrix. To the best of our knowledge, this is the first finite
sample result that captures the effect of the canonical correlations on the
minimax rates.


title:
Item Popularity Prediction in E-commerce Using Image Quality Feature
  Vectors

abstract:
  Online retail is a visual experience- Shoppers often use images as first
order information to decide if an item matches their personal style. Image
characteristics such as color, simplicity, scene composition, texture, style,
aesthetics and overall quality play a crucial role in making a purchase
decision, clicking on or liking a product listing. In this paper we use a set
of image features that indicate quality to predict product listing popularity
on a major e-commerce website, Etsy. We first define listing popularity through
search clicks, favoriting and purchase activity. Next, we infer listing quality
from the pixel-level information of listed images as quality features. We then
compare our findings to text-only models for popularity prediction. Our initial
results indicate that a combined image and text modeling of product listings
outperforms text-only models in popularity prediction.


title: Real-Time Web Scale Event Summarization Using Sequential Decision Making

abstract:
  We present a system based on sequential decision making for the online
summarization of massive document streams, such as those found on the web.
Given an event of interest (e.g. "Boston marathon bombing"), our system is able
to filter the stream for relevance and produce a series of short text updates
describing the event as it unfolds over time. Unlike previous work, our
approach is able to jointly model the relevance, comprehensiveness, novelty,
and timeliness required by time-sensitive queries. We demonstrate a 28.3%
improvement in summary F1 and a 43.8% improvement in time-sensitive F1 metrics.


title:
Constraints on MACHO Dark Matter from Compact Stellar Systems in
  Ultra-Faint Dwarf Galaxies

abstract:
  I show that a recently discovered star cluster near the center of the
ultra-faint dwarf galaxy Eridanus II provides strong constraints on massive
compact halo objects (MACHOs) of >~5 M_sun as the main component of dark
matter. MACHO dark matter will dynamically heat the cluster, driving it to
larger sizes and higher velocity dispersions until it dissolves into its host
galaxy. The stars in compact ultra-faint dwarf galaxies themselves will be
subject to the same dynamical heating; the survival of at least ten such
galaxies places independent limits on MACHO dark matter of masses >~10 M_sun.
Both Eri II's cluster and the compact ultra-faint dwarfs are characterized by
stellar masses of just a few thousand M_sun and half-light radii of 13 pc (for
the cluster) and ~30 pc (for the ultra-faint dwarfs). These systems close the
~20--100 M_sun window of allowed MACHO dark matter and combine with existing
constraints from microlensing, wide binaries, and disk kinematics to rule out
dark matter composed entirely of MACHOs from ~10$^{-7}$ M_sun up to arbitrarily
high masses.


title:
Design and control of cross-coupled mechanisms driven by AC brushless
  servo motors

abstract:
  This paper presents an overview of a design methodology for the optimal
synthesis of hybrid mechanisms. Hybrid mechanisms have been defined as
multi-degree of freedom systems where the input motions are supplied by
different motor types. In this work a five bar mechanism is designed for a
given task under the constraint that one input axis rotates with constant
velocity whilst the other input can exhibit any motion requirement. A machine
of this type is classified as being cross-coupled due to the mechanical linkage
between the input axes. Cross-coupling implies that the input motion on one
axis effects the position of the other input axis. This can lead to either
opposition to, or accentuation of the control system input. Such a system as
this is difficult to control due to the compensation for this on each axis
leading to further disturbance. Results are presented for a real machine
operating in this way and the actual output of the machine is compared to the
desired input of the machine.


title:
A comparison of two methods applied to the optimisation of fluid power
  circuits

abstract:
  This paper describes two optimisation methods which can be applied to the
parameter selection stage of Fluid Power System design. These two methods used
are a Genetic Algorithm (GA) and a Tabu Search method, both of which have been
claimed to be truely global methods. GAs are a method inspired by natural
selection and Darwinian evolution whilst Tabu Search is an aggressive search
metaheuristic which guides local search methods towards the globally optimum
solution. Results are presented for two different circuit optimisation tasks.
These results show that each of the two methods have both advantages and
disadvantages.


title: The Binding Energy Parameter for Common Envelope Evolution

abstract:
  The binding energy parameter $\lambda$ plays a vital role in common envelope
evolution. Though it is well known that $\lambda$ takes different values for
stars with different masses and varies during stellar evolution, it has been
erroneously adopted as a constant in most of the population synthesis
calculations. We have systematically calculated the values of $\lambda$ for
stars of masses $1-60\,M_{\odot}$ by use of an updated stellar evolution code,
taking into account contribution from both gravitational energy and internal
energy to the binding energy of the envelope. We adopt the criterion for the
core-envelope boundary advocated by \citet{Ivanova2011}. A new kind of
$\lambda$ with the enthalpy prescription is also investigated. We present
fitting formulae for the calculated values of various kinds of $\lambda$, which
can be used in future population synthesis studies.


title:
Can the Subsonic Accretion Model Explain the Spin Period Distribution of
  Wind-fed X-ray Pulsars?

abstract:
  Neutron stars in high-mass X-ray binaries (HMXBs) generally accrete from the
wind matter of their massive companion stars. Recently Shakura et al. (2012)
suggested a subsonic accretion model for low-luminosity ($<4\times 10^{36}$
ergs$^{-1}$), wind-fed X-ray pulsars. To test the feasibility of this model, we
investigate the spin period distribution of wind-fed X-ray pulsars with a
supergiant companion star, using a population synthesis method. We find that
the modeled distribution of supergiant HMXBs in the spin period - orbital
period diagram is consistent with observations provided that the winds from the
donor stars have relatively low terminal velocities ($\lesssim 1000$
kms$^{-1}$). The measured wind velocities in several supergiant HMXBs seem to
favor this viewpoint. The predicted number ratio of wind-fed X-ray pulsars with
persistent X-ray luminosities higher and lower than $4\times 10^{36}$
ergs$^{-1}$ is about $1:10$.


title:
Optimisation of power transmission systems using a discrete Tabu Search
  method

abstract:
  This paper presents a brief description of the Tabu Search method and shows
how it can be applied to two different power transmission systems. Examples are
presented from two transmission systems. In the first example a mechanical
transmission system is considered. A four bar mechanism is synthesised in order
to produce a desired output motion. The second example is a hydrostatic
transmission operating under closed loop control in order to maintain a
constant operating speed as the loading conditions change.


title:
Crossover from Shear-Driven to Thermally Activated Drainage of
  Liquid-Infused Microscale Capillaries

abstract:
  The shear-driven drainage of capillary grooves filled with viscous liquid is
a dynamic wetting phenomenon relevant to numerous industrial processes and
novel lubricant-infused surfaces. Prior work has reported that a finite length
$L_\infty$ of the capillary groove can remain indefinitely filled with liquid
even when large shear stresses are applied. The mechanism preventing full
drainage is attributed to a balance between the shear-driven flow and a
counterflow driven by capillary pressures caused by deformation of the free
surface. The final equilibrium length $L_\infty$ is uniquely determined by
physical properties of the filling liquid as well as the geometry and
wettability of the capillary. In this work, we examine closely the approach to
the final equilibrium length $L_\infty$ and report a crossover to a slow
drainage regime that cannot be described by conventional dynamic models
considering solely hydrodynamic and capillary forces. The slow drainage regime
observed in experiments can be instead modeled by a kinetic equation describing
a sequence of random thermally activated transitions between multiple
metastable states caused by surface defects with nanoscale dimensions. Our
findings provide new insights on the critical role that natural or engineered
surface roughness with nanoscale dimensions can play in the imbibition and
drainage of capillaries and other dynamic wetting processes in microscale
systems.


title:
SXP214, an X-ray Pulsar in the Small Magellanic Cloud, Crossing the
  Circumstellar Disk of the Companion

abstract:
  Located in the Small Magellanic Cloud (SMC), SXP214 is an X-ray pulsar in a
high mass X-ray binary system with a Be-star companion. A recent survey of the
SMC under a Chandra X-ray Visionary program found the source in a transition
when the X-ray flux was on a steady rise. The Lomb-Scargle periodogram revealed
a pulse period of 211.49 +/- 0.42 s, which is significantly (>5sigma) shorter
than the previous measurements with XMM-Newton and RXTE. This implies that the
system has gone through sudden spin-up episodes recently. The pulse profile
shows a sharp eclipse-like feature with a modulation amplitude of >95%. The
linear rise of the observed X-ray luminosity from <~2x to 7x10^35 erg s^-1 is
correlated with steady softening of the X-ray spectrum, which can be described
by the changes in the local absorption from N_H ~ 10^24 to <~10^20 cm^-2 for an
absorbed power-law model. The soft X-ray emission below 2 keV was absent in the
early part of the observation when only the pulsating hard X-ray component was
observed, whereas at later times both soft and hard X-ray components were
observed pulsating. A likely explanation is that the neutron star was initially
hidden in the circumstellar disk of the companion, and later came out of the
disk with the accreted material that continued fueling the observed pulsation.


title: Comprehensive analysis of the optical Kerr coefficient of graphene

abstract:
  We present a comprehensive analysis of the the nonlinear optical Kerr effect
in graphene. We directly solve the S-matrix element to calculate the absorption
rate, utilizing the Volkov-Keldysh- type crystal wave functions. We then
convert to the nonlinear refractive index coefficients through the
Kramers-Kronig relation. In this formalism, the source of Kerr nonlinearity is
the interplay of optical fields that cooperatively drive the transition from
valence to conduction band. This formalism makes it possible to identify and
compute the rates of distinct nonlinear processes that contribute to the Kerr
nonlinear refractive index coefficient. The four identified mechanisms are two
photon absorption, Raman transition, self coupling, and quadratic AC Stark
effect. We also present a comparison of our theory with recent experimental and
theoretical results.


title:
In-gas-cell laser spectroscopy for magnetic dipole moment of $^{199}$Pt
  toward $N=$ 126

abstract:
  Magnetic dipole moment and mean-square charge radius of $^{199}$Pt
($I^{\pi}=$ 5/2$^-$) have been evaluated for the first time from the
investigation of the hyperfine splitting of the $\lambda_1=$ 248.792 nm
transition by in-gas-cell laser ionization spectroscopy. Neutron-rich nucleus
$^{199}$Pt was produced by multi-nucleon transfer reaction at the KISS where
the nuclear spectroscopy in the vicinity of $N=$ 126 is planed from the aspect
of an astrophysical interest as well as the nuclear structure. Measured
magnetic dipole moment $+$0.63(13)$\mu_{\rm N}$ is consistent with the
systematics of those of nuclei with $I^{\pi}=$ 5/2$^-$. The deformation
parameter $|<\beta_2^2>^{1/2}|$ evaluated from the isotope shift indicates the
gradual shape change to spherical shape of platinum isotopes with increasing
neutron number toward $N=$ 126.


title:
Probing the deep end of the Milky Way with \emph{Kepler}: Asteroseismic
  analysis of 854 faint Red Giants misclassified as Cool Dwarfs

abstract:
  Asteroseismology has proven to be an excellent tool to determine not only the
global stellar properties with a good precision but also to infer stellar
structure, dynamics, and evolution for a large sample of Kepler stars. Prior to
the launch of the mission the properties of Kepler targets were inferred from
broadband photometry, leading to the Input Catalog (KIC Brown et al. 2011). The
KIC was later revised in the Kepler Star Properties Catalog (Huber et al.
2014), based on literature values and an asteroseismic analysis of stars which
were unclassified in the KIC. Here we present an asteroseismic analysis of
45,400 stars which were classified as dwarfs in the Kepler Star Properties
Catalog. We found that around 2% of the sample shows acoustic modes in the
typical frequency range that put them in the red-giant category rather than
cool dwarfs. We analyse the asteroseismic properties of these stars, derive
their surface gravities, masses, and radii and present updated effective
temperatures and distances. We show that the sample is significantly fainter
than the previously known oscillating giants in the Kepler field, with the
faintest stars reaching down to a Kepler magnitude, Kp~16. We demonstrate that
404 stars are at distances beyond 5 kpc and that the stars are significantly
less massive than for the original Kepler red-giant sample, consistent with a
population of distant halo giants. A comparison with a galactic population
model shows that up to 40 stars might be genuine halo giants, which would
increase the number of known asteroseismic halo stars by a factor of 4. The
detections presented here will provide a valuable sample for galactic
archeology studies.


title:
Ab initio electronic structure of quasi two-dimensional materials: a
  "native" gaussian--plane wave approach

abstract:
  Ab initio electronic structure calculations of two-dimensional layered
structures are typically performed using codes that were developed for
three-dimensional structures, which are periodic in all three directions. The
introduction of a periodicity in the third direction (perpendicular to the
layer) is completely artificial and may lead in some cases to spurious results
and to difficulties in treating the action of external fields. In this paper we
develop a new approach, which is "native" to quasi-2D materials, making use of
basis function that are periodic in the plane, but atomic-like in the
perpendicular direction. We show how some of the basic tools of ab initio
electronic structure theory -- density functional theory, GW approximation and
Bethe-Salpeter equation -- are implemented in the new basis. We argue that the
new approach will be preferable to the conventional one in treating the
peculiarities of layered materials, including the long range of the unscreened
Coulomb interaction in insulators, and the effects of strain, corrugations, and
external fields.


title: On falsification of the binary instrumental variable model

abstract:
  Instrumental variables are widely used for estimating causal effects in the
presence of unmeasured confounding. The discrete instrumental variable model
has testable implications on the law of the observed data. However, current
assessments of instrumental validity are typically based solely on
subject-matter arguments rather than these testable implications, partly due to
a lack of formal statistical tests with known properties. In this paper, we
develop simple procedures for testing the binary instrumental variable model.
Our methods are based on existing approaches for comparing two treatments, such
as the t-test and the Gail--Simon test. We illustrate the importance of testing
the instrumental variable model by evaluating the exogeneity of college
proximity using the National Longitudinal Survey of Young Men.


title: Energy-aware Traffic Engineering in Hybrid SDN/IP Backbone Networks

abstract:
  Software Defined Networking (SDN) can effectively improve the performance of
traffic engineering and has promising application foreground in backbone
networks. Therefore, new energy saving schemes must take SDN into account,
which is extremely important considering the rapidly increasing energy
consumption from Telecom and ISP networks. At the same time, the introduction
of SDN in a current network must be incremental in most cases, for both
technical and economic reasons. During this period, operators have to manage
hybrid networks, where SDN and traditional protocols coexist. In this paper, we
study the energy efficient traffic engineering problem in hybrid SDN/IP
networks. We first formulate the mathematic optimization model considering
SDN/IP hybrid routing mode. As the problem is NP-hard, we propose the fast
heuristic algorithm named HEATE (Hybrid Energy-Aware Traffic Engineering). In
our proposed HEATE algorithm, the IP routers perform the shortest path routing
using the distribute OSPF link weight optimization. The SDNs perform the
multi-path routing with traffic flow splitting by the global SDN controller.
The HEATE algorithm finds the optimal setting of OSPF link weight and splitting
ratio of SDNs. Thus traffic flow is aggregated onto partial links and the
underutilized links can be turned off to save energy. By computer simulation
results, we show that our algorithm has a significant improvement in energy
efficiency in hybrid SDN/IP networks.


title: Resilience to time-correlated noise in quantum computation

abstract:
  Fault-tolerant quantum computation techniques rely on weakly correlated
noise. Here I show that it is enough to assume weak spatial correlations: time
correlations can take any form. In particular, single-shot error correction
techniques exhibit a noise threshold for quantum memories under spatially local
stochastic noise.


title:
Enhancing the blocking temperature of perpendicular-exchange biased
  Cr2O3 thin films using spacer and buffer layers

abstract:
  In this study, we investigated the effect of spacer and buffer layers on the
blocking temperature TB of the perpendicular exchange bias of thin Cr2O3 films,
and revealed a high TB of 260 K for 20-nm-thick Cr2O3 thin films. By inserting
a Ru spacer layer between the Cr2O3 and Co films and changing the spacer
thickness, we controlled the magnitude of the exchange bias and TB. By
comparing the TB values of the 20-nm-thick Cr2O3 films on Pt and alpha-Fe2O3
buffers, we investigated the lattice strain effect on the TB. We show that
higher TB value can be obtained using an alpha-Fe2O3 buffer, which is likely
because of the lattice-strain-induced increase of Cr2O3 magnetic anisotropy.


title:
Local structural distortion induced by antiferromagnetic ordering in
  Bi$_2$Fe$_4$O$_9$ studied using neutron total scattering analysis

abstract:
  To unravel the origin of the dielectric anomaly at the antiferromagnetic
ordering of magnetoelectric Bi$_2$Fe$_4$O$_9$ we performed neutron powder
diffraction measurements across the N$\acute{\rm e}$el temperature, $T_{\rm
N}$. Both local structures and long-range symmetry are studied using the
complementary analyses of atomic pair distribution function (PDF) and Rietveld
methods at temperatures 300~K, 250~K, and 200~K. We present that PDF peaks
which reflect local atomic arrangements exhibit a noticeable variation below
$T_{\rm N}$ without long-range symmetry change. The implication of the PDF
evolution is discussed in view of a local structural distortion at the onset of
the antiferromagnetic ordering.


title: Effective quasimorphisms on free chains

abstract:
  We find homogeneous counting quasimorphisms that are effective at seeing
chains in a free group F. As corollary, we derive that if a group G has an
index-d free subgroup, then every element g in G either has stable commutator
length at least 1/8d or some power of g is conjugate to its inverse. We also
show that for a finitely-generated free group F, there is a countable basis for
the real vector space of homogeneous quasimorphisms on F.


title:
Optimality of VWAP Execution Strategies under General Shaped Market
  Impact Functions

abstract:
  In this short note, we study an optimization problem of expected
implementation shortfall (IS) cost under general shaped market impact
functions. In particular, we find that an optimal strategy is a VWAP (volume
weighted average price) execution strategy when the market model is a
Black-Scholes type with stochastic clock and market trading volume is large.


title:
Density Functional Theory study on the electronic structure and
  thermoelectric properties of strained Mn4Si7

abstract:
  The strain effect on electronic structure and thermoelectric properties of
Higher Manganese Silicides (HMSs) Mn4Si7 was studied using Density Functional
Theory (DFT) and through solving Boltzman Transport Equation (BTE). We found
that the tensile strain attempts to reduce the band gap while the compressive
strain not much affect to band gap. The Seebeck coeficient was found to be
increased with increasing temperature, which is very consistent to experiments.
The electrical conductivity and power factor show highly degree of anisotropy,
where in-plane direction is more dominant. The different behavior of electrical
conductivity along in-plane and outof plane direction was explained due to the
change of band dispersion in the valence band maximum (VBM).


title: No-enclave percolation corresponds to holes in the cluster backbone

abstract:
  The no-enclave percolation (NEP) model introduced recently by Sheinman et al.
can be mapped to a problem of holes within a standard percolation backbone, and
numerical measurements of these holes gives the size-distribution exponent
$\tau = 1.82(1)$ of the NEP model. An argument is given that $\tau=1 + d_B/2
\approx 1.822$ where $d_B$ is the backbone dimension. On the other hand, a
model of simple holes within a percolation cluster implies $\tau = 1 + d_f/2 =
187/96 \approx 1.948$, where $d_f$ is the fractal dimension of the cluster, and
this value is consistent with Sheinman et al.'s experimental results of gel
collapse which gives $\tau = 1.91(6)$. Both models yield a discontinuous
maximum hole size at $p_c$, signifying explosive percolation behavior. At
$p_c$, the largest hole fills exactly half the system, due to symmetry.
Extensive numerical simulations confirm our results.


title: Perturbative Approach to Superfluidity under Nonuniform Potential

abstract:
  A perturbative way to investigate superfluid properties of various systems
under nonuniform potential is presented. We derive the perturbation expansion
of the superfluid fraction, which indicates how liquid exhibits nonclassical
rotational inertia, in terms of the strength of nonuniform potential and find
that the coefficient of the leading term reflects the density fluctuation of
the system. Our formulation does not assume anything about Bose-Einstein
condensation and thus is applicable to wide variety of systems. Superfluid
properties of some examples including (non-)interacting Bose systems,
especially Bose gas in the mean field limit, (non-)interacting Fermi sytems,
Tomonaga-Luttinger liquid and spinless chiral $p$-wave superfluid are
investigated.


title:
Effect of magnetic field on a magnetic topological insulator film with
  structural inversion asymmetry

abstract:
  The effect of magnetic field on an ultrathin magnetic topological insulator
film with structural inversion asymmetry is investigated. We introduce the
phase diagram, calculate the Landau-level spectrum analytically and simulate
the transport behavior in Landauer-B\"uttiker formalism. The quantum anomalous
Hall phase will survive increasing magnetic field. Due to the two spin
polarized zero modes of Landau levels a nontrivial phase similar with quantum
spin Hall effect can be induced by magnetic field which is protected by
structural inversion symmetry. Some exotic longitudinal and Hall resistance
plateaus with fractional values are also found in a six terminal Hall bar,
arising from the coupling between edge states due to inverted energy band and
Landau levels.


title: Going Deeper into First-Person Activity Recognition

abstract:
  We bring together ideas from recent work on feature design for egocentric
action recognition under one framework by exploring the use of deep
convolutional neural networks (CNN). Recent work has shown that features such
as hand appearance, object attributes, local hand motion and camera ego-motion
are important for characterizing first-person actions. To integrate these ideas
under one framework, we propose a twin stream network architecture, where one
stream analyzes appearance information and the other stream analyzes motion
information. Our appearance stream encodes prior knowledge of the egocentric
paradigm by explicitly training the network to segment hands and localize
objects. By visualizing certain neuron activation of our network, we show that
our proposed architecture naturally learns features that capture object
attributes and hand-object configurations. Our extensive experiments on
benchmark egocentric action datasets show that our deep architecture enables
recognition rates that significantly outperform state-of-the-art techniques --
an average $6.6\%$ increase in accuracy over all datasets. Furthermore, by
learning to recognize objects, actions and activities jointly, the performance
of individual recognition tasks also increase by $30\%$ (actions) and $14\%$
(objects). We also include the results of extensive ablative analysis to
highlight the importance of network design decisions..


title:
Robust and Efficient Relative Pose with a Multi-camera System for
  Autonomous Vehicle in Highly Dynamic Environments

abstract:
  This paper studies the relative pose problem for autonomous vehicle driving
in highly dynamic and possibly cluttered environments. This is a challenging
scenario due to the existence of multiple, large, and independently moving
objects in the environment, which often leads to excessive portion of outliers
and results in erroneous motion estimation. Existing algorithms cannot cope
with such situations well. This paper proposes a new algorithm for relative
pose using a multi-camera system with multiple non-overlapping individual
cameras. The method works robustly even when the numbers of outliers are
overwhelming. By exploiting specific prior knowledge of driving scene we have
developed an efficient 4-point algorithm for multi-camera relative pose, which
admits analytic solutions by solving a polynomial root-finding equation, and
runs extremely fast (at about 0.5$u$s per root). When the solver is used in
combination with RANSAC, we are able to quickly prune unpromising hypotheses,
significantly improve the chance of finding inliers. Experiments on synthetic
data have validated the performance of the proposed algorithm. Tests on real
data further confirm the method's practical relevance.


title:
The production of proton-rich isotopes beyond iron: The $\gamma$ process
  in stars

abstract:
  Beyond iron, a small fraction of the total abundances in the Solar System is
made of proton-rich isotopes, the p nuclei. The clear understanding of their
production is a fundamental challenge for nuclear astrophysics. The p nuclei
constrain the nucleosynthesis in core-collapse and thermonuclear supernovae.
The $\gamma$ process is the most established scenario for the production of the
p nuclei, which are produced via different photodisintegration paths starting
on heavier nuclei. A large effort from nuclear physics is needed to access the
relevant nuclear reaction rates far from the valley of stability. This review
describes the production of the heavy proton-rich isotopes by the $\gamma$
process in stars, and explores the state of the art of experimental nuclear
physics to provide nuclear data for stellar nucleosynthesis.


title:
The presence of quantum correlations result in non-vanishing ergotropic
  gap

abstract:
  The paradigm of extracting work from isolated quantum system through a cyclic
Hamiltonian process is a topic of immense research interest. The optimal work
extracted under such process is termed as ergotropy [Europhys. Lett., 67 (4),
565(2004)]. Here, in a multi-party scenario we consider only a class of such
cyclic processes that can be implemented locally, giving rise to the concept of
local ergotropy. Eventually, presence of quantum correlations result in a
non-vanishing thermodynamic quantity called ergotropic gap, measured by the
difference between the global and local ergotropy. However the converse does
not hold in general, i.e. its nonzero value does not necessarily imply presence
of quantum correlations. For arbitrary multi-party states we quantify this gap.
We also evaluate the difference between maximum global and local extractable
work for arbitrary states when the system is no longer isolated but put in
contact with a baths of same local temperature.


title: The Non-Uniform k-Center Problem

abstract:
  In this paper, we introduce and study the Non-Uniform k-Center problem
(NUkC). Given a finite metric space $(X,d)$ and a collection of balls of radii
$\{r_1\geq \cdots \ge r_k\}$, the NUkC problem is to find a placement of their
centers on the metric space and find the minimum dilation $\alpha$, such that
the union of balls of radius $\alpha\cdot r_i$ around the $i$th center covers
all the points in $X$. This problem naturally arises as a min-max vehicle
routing problem with fleets of different speeds.
  The NUkC problem generalizes the classic $k$-center problem when all the $k$
radii are the same (which can be assumed to be $1$ after scaling). It also
generalizes the $k$-center with outliers (kCwO) problem when there are $k$
balls of radius $1$ and $\ell$ balls of radius $0$. There are $2$-approximation
and $3$-approximation algorithms known for these problems respectively; the
former is best possible unless P=NP and the latter remains unimproved for 15
years.
  We first observe that no $O(1)$-approximation is to the optimal dilation is
possible unless P=NP, implying that the NUkC problem is more non-trivial than
the above two problems. Our main algorithmic result is an
$(O(1),O(1))$-bi-criteria approximation result: we give an $O(1)$-approximation
to the optimal dilation, however, we may open $\Theta(1)$ centers of each
radii. Our techniques also allow us to prove a simple (uni-criteria), optimal
$2$-approximation to the kCwO problem improving upon the long-standing
$3$-factor. Our main technical contribution is a connection between the NUkC
problem and the so-called firefighter problems on trees which have been studied
recently in the TCS community.


title:
Generating spin squeezing states and Greenberger-Horne-Zeilinger
  entanglement using a hybrid phonon-spin ensemble in diamond

abstract:
  Quantum squeezing and entanglement of spins can be used to improve the
sensitivity in quantum metrology. Here we propose a scheme to create collective
coupling of an ensemble of spins to mechanical vibrational mode actuated by an
external magnetic field. We find an evolution time where the mechanical motion
decouples from the spins, and the accumulated geometric phase yields a
squeezing of $5.9~\text{dB}$ for $20$ spins. We also show the creation of a
Greenberger-Horne-Zeilinger spin state for $20$ spins with a fidelity of $\sim
0.62$ at cryogenic temperature. The numerical simulations show that the
geometric-phase based scheme is mostly immune to thermal mechanical noise.


title:
Fragmenting networks by targeting collective influencers at a mesoscopic
  level

abstract:
  A practical approach to protecting networks against epidemic processes such
as spreading of infectious diseases, malware, and harmful viral information is
to remove some influential nodes beforehand to fragment the network into small
components. Because determining the optimal order to remove nodes is a
computationally hard problem, various approximate algorithms have been proposed
to efficiently fragment networks by sequential node removal. Morone and Makse
proposed an algorithm employing the non-backtracking matrix of given networks,
which outperforms various existing algorithms. In fact, many empirical networks
have community structure, compromising the assumption of local tree-like
structure on which the original algorithm is based. We develop an immunization
algorithm by synergistically combining the Morone-Makse algorithm and coarse
graining of the network in which we regard a community as a supernode. In this
way, we aim to identify nodes that connect different communities at a
reasonable computational cost. The proposed algorithm works more efficiently
than the Morone-Makse and other algorithms on networks with community
structure.


title: p-Capitulation over number fields with p-class rank two

abstract:
  Theoretical foundations of a new algorithm for determining the p-capitulation
type kappa(K) of a number field K with p-class rank rho=2 are presented. Since
kappa(K) alone is insufficient for identifying the second p-class group
G=Gal(F(p,2,K) | K) of K, complementary techniques are developed for finding
the nilpotency class and coclass of G. An implementation of the complete
algorithm in the computational algebra system Magma is employed for calculating
the Artin pattern AP(K)=(tau(K),kappa(K)) of all 34631 real quadratic fields
K=Q(squareroot(d)) with discriminants 0<d<100000000 and 3-class group of type
(3,3). The results admit extensive statistics of the second 3-class groups
G=Gal(F(3,2,K) | K) and the 3-class field tower groups H=Gal(F(3,K) | K).


title: Classical dynamics of the Bianchi IX model with timelike singularity

abstract:
  We study the dynamics of the vacuum Bianchi IX model with timelike
singularity and compare it with the dynamics of the Bianchi IX model with
cosmological singularity. We show that differences in the signs of some terms
in the set of equations specifying the dynamics of both spacetimes lead to
significant differences in their properties.


title:
Weighted SAMGSR: combining significance analysis of microarray-gene set
  reduction algorithm with pathway topology-based weights to select relevant
  genes

abstract:
  Introduction
  It has been demonstrated that a pathway-based feature selection method which
incorporates biological information within pathways into the process of feature
selection usually outperform a gene-based feature selection algorithm in terms
of predictive accuracy, stability, and biological interpretation. Significance
analysis of microarray-gene set reduction algorithm (SAMGSR), an extension to a
gene set analysis method with further reduction of the selected pathways to
their respective core subsets, can be regarded as a pathway-based feature
selection method.
  Results and Discussion
  In SAMGSR, whether a gene is selected is mainly determined by its expression
difference between the phenotypes, and partially by the number of pathways to
which this gene belongs, but ignoring the topology information among pathways.
In this study, we propose a weighted version of the SAMGSR algorithm by
constructing weights based on the connectivity among genes and then
incorporating these weights in the test statistic.
  Conclusions
  Using both simulated and real-world data, we evaluate the performance of the
proposed SAMGSR extension and demonstrate that gene connectivity is indeed
informative for feature selection.


title:
A note on constructing sharp examples for $L^{p}$ norms of
  eigenfunctions and quasimodes near submanifolds

abstract:
  In this note we analyse $L^{p}$ estimates for Laplacian eigenfunctions and
quasimodes and their associated sharp examples. In particular we use previously
determined estimates to produce a new set of estimates for restriction to
thickened neighbourhoods of submanifolds. In addition we produce a family flat
model quasimode examples that can be used to determine sharpness of estimates
on Laplacian eigenfunctions restricted to subsets. For each quasimode in the
family we show that there is a corresponding spherical harmonic that displays
the same growth properties. Therefore it is enough to check $L^{p}$ growth
estimates against the simple flat model examples. Finally we present a
heuristic that for any subset determines which quasimode in the family is
expected to produce sharp examples.


title: Three nucleon forces in nuclear matter in the QCD sum rules

abstract:
  We calculate the single-particle nucleon characteristics in symmetric nuclear
matter with inclusion of the 3N interactions. The contribution of the 3N forces
to the nucleon self energies are expressed in terms of the nonlocal scalar
condensate (d=3) and of the configuration of the two four-quark condensates
(d=6) in which two diquark operators act on two different nucleons of the
matter. The most important part of the contribution of the four-quark
condensate is calculated in a model-independent way. We employed a relativistic
quark model of nucleon for calculation of the rest part. The density dependence
of the vector and scalar nucleon self energies and of the single-particle
potential energy are obtained.


title:
Scalable, ultra-resistant structural colors based on network
  metamaterials

abstract:
  Structural colours have drawn wide attention for their potential as a future
printing technology for various applications, ranging from biomimetic tissues
to adaptive camouflage materials. However, an efficient approach to realise
robust colours with a scalable fabrication technique is still lacking,
hampering the realisation of practical applications with this platform. Here we
develop a new approach based on large scale network metamaterials, which
combine dealloyed subwavelength structures at the nanoscale with loss-less,
ultra-thin dielectrics coatings. By using theory and experiments, we show how
sub-wavelength dielectric coatings control a mechanism of resonant light
coupling with epsilon-near-zero (ENZ) regions generated in the metallic
network, manifesting the formation of highly saturated structural colours that
cover a wide portion of the spectrum. Ellipsometry measurements report the
efficient observation of these colours even at angles of $70$ degrees. The
network-like architecture of these nanomaterials allows for high mechanical
resistance, which is quantified in a series of nano-scratch tests. With such
remarkable properties, these metastructures represent a robust design
technology for real-world, large scale commercial applications.


title:
Effects of symmetry energy in $^{132}\rm {Sn}+^{124}\rm {Sn}$ reaction
  at 300 MeV/nucleon

abstract:
  Based on the recently updated Isospin-dependent Boltzmann-Uehling-Uhlenbeck
(IBUU) transport model, we studied the effects of symmetry energy on the
neutron to proton n/p ratio and the $\pi^{-}/\pi^{+}$ ratio in central
$^{132}\rm {Sn}+^{124}\rm {Sn}$ reaction at 300 MeV/nucleon. It is found that
the n/p ratio and the $\pi^{-}/\pi^{+}$ ratio in central $^{132}\rm
{Sn}+^{124}\rm {Sn}$ reaction at 300 MeV/nucleon mainly probe the symmetry
energy in the density region 1-1.5 times saturation density. However, the
$\pi^{-}/\pi^{+}$ ratio may be able to probe the density-dependent symmetry
energy above 1.5 times saturation density by making some kinematic restrictions
such as the azimuthal angle and kinetic energy cuts of emitting pions.


title:
Analytical Model for Outdoor Millimeter Wave Channels using
  Geometry-Based Stochastic Approach

abstract:
  The severe bandwidth shortage in conventional microwave bands has spurred the
exploration of the millimeter wave (MMW) spectrum for the next revolution in
wireless communications. However, there is still lack of proper channel
modeling for the MMW wireless propagation, especially in the case of outdoor
environments. In this paper, we develop a geometry-based stochastic channel
model to statistically characterize the effect of all the first-order
reflection paths between the transmitter and receiver. These first-order
reflections are generated by the single-bounce of signals reflected from the
walls of randomly distributed buildings. Based on this geometric model, a
closed-form expression for the power delay profile (PDP) contributed by all the
first-order reflection paths is obtained and then used to evaluate their impact
on the MMW outdoor propagation characteristics. Numerical results are provided
to validate the accuracy of the proposed model under various channel parameter
settings. The findings in this paper provide a promising step towards more
complex and practical MMW propagation channel modeling.


title:
Temporal and spatial relationship of flare signatures and the force-free
  coronal magnetic field

abstract:
  We investigate the plasma and magnetic environment of active region NOAA
11261 on 2 August 2011 around a GOES M1.4 flare/CME (SOL2011-08-02T06:19). We
compare coronal emission at (extreme) ultraviolet and X-ray wavelengths, using
SDO AIA and RHESSI images, in order to identify the relative timing and
locations of reconnection-related sources. We trace flare ribbon signatures at
ultraviolet wavelengths, in order to pin down the intersection of previously
reconnected flaring loops at the lower solar atmosphere. These locations are
used to calculate field lines from 3D nonlinear force-free magnetic field
models, established on the basis of SDO HMI photospheric vector magnetic field
maps. With this procedure, we analyze the quasi-static time evolution of the
coronal model magnetic field previously involved in magnetic reconnection. This
allows us, for the first time, to estimate the elevation speed of the current
sheet's lower tip during an on-disk observed flare, as a few kilometers per
second. Comparison to post-flare loops observed later above the limb in STEREO
EUVI images supports this velocity estimate. Furthermore, we provide evidence
for an implosion of parts of the flaring coronal model magnetic field, and
identify the corresponding coronal sub-volumes associated to the loss of
magnetic energy. Finally, we spatially relate the build up of magnetic energy
in the 3D models to highly sheared fields, established due to dynamic relative
motions of polarity patches within the active region.


title:
Right orthogonal class of pure projective modules over pure hereditary
  rings

abstract:
  Let $\mathcal{W}$ be the class of all pure projective modules. In this
article, $\mathcal{W}$-injective modules is defined via the vanishing of
cohomology of pure projective modules. First we show that every module has a
$\mathcal{W}$-injective coresolution over an arbitrary ring and the class of
all $\mathcal{W}$-injective modules is coresolving over a pure-hereditary ring.
Further, we analyze the dimension of $\mathcal{W}$-injective coresolution over
a pure-hereditary ring. It is shown that $\Fcor_{\mathcal{W}^{\bot}}(R) =
\sup\{\pd(G) \colon G$ is a pure projective $R$-module$\} =
\sup\{\cores_{\mathcal{W}^{\bot}}(M) \colon M $ is an $R$-module$\}.$ Finally,
we give some equivalent conditions of $\mathcal{W}$-injective envelope with the
unique mapping property. The dimension has desirable properties when the ring
is semisimple artinian.


title: Movie Description

abstract:
  Audio Description (AD) provides linguistic descriptions of movies and allows
visually impaired people to follow a movie along with their peers. Such
descriptions are by design mainly visual and thus naturally form an interesting
data source for computer vision and computational linguistics. In this work we
propose a novel dataset which contains transcribed ADs, which are temporally
aligned to full length movies. In addition we also collected and aligned movie
scripts used in prior work and compare the two sources of descriptions. In
total the Large Scale Movie Description Challenge (LSMDC) contains a parallel
corpus of 118,114 sentences and video clips from 202 movies. First we
characterize the dataset by benchmarking different approaches for generating
video descriptions. Comparing ADs to scripts, we find that ADs are indeed more
visual and describe precisely what is shown rather than what should happen
according to the scripts created prior to movie production. Furthermore, we
present and compare the results of several teams who participated in a
challenge organized in the context of the workshop "Describing and
Understanding Video & The Large Scale Movie Description Challenge (LSMDC)", at
ICCV 2015.


title:
Climate change and integrodifference equations in a stochastic
  environment

abstract:
  Climate change impacts population distributions, forcing some species to
migrate poleward if they are to survive and keep up with the suitable habitat
that is shifting with the temperature isoclines. Previous studies have analyzed
whether populations have the capacity to keep up with shifting temperature
isoclines, and have mathematically determined the combination of growth and
dispersal that is needed to achieve this. However, the rate of isocline
movement can be highly variable, with much uncertainty associated with yearly
shifts. The same is true for population growth rates. Growth rates can be
variable and uncertain, even within suitable habitats for growth. In this paper
we reanalyze the question of population persistence in the context of the
uncertainty and variability in isocline shifts and rates of growth.
Specifically, we employ a stochastic integrodifference equation model on a
patch of suitable habitat that shifts poleward at a random rate. We derive a
metric describing the asymptotic growth rate of the linearized operator of the
stochastic model and yielding a threshold criterion for population persistence.
We demonstrate that the variability in the yearly shift and in the growth rate
has a significant negative effect on the persistence in the sense that it
decreases the threshold criterion for population persistence. Mathematically,
we show how the persistence metric can be connected to the principal eigenvalue
problem for a related integral operator, at least for the case where isocline
shifting speed is deterministic. Analysis of dynamics for the case where the
dispersal kernel is Gaussian leads to the existence of a critical shifting
speed. Finally we illustrate our different results for butterfly population
using numerical simulations and demonstrate how increased variances in isocline
shifts and growth rates translate into decreased likelihoods of persistence.


title: Optimal Bayes Classifiers for Functional Data and Density Ratios

abstract:
  Bayes classifiers for functional data pose a challenge. This is because
probability density functions do not exist for functional data. As a
consequence, the classical Bayes classifier using density quotients needs to be
modified. We propose to use density ratios of projections on a sequence of
eigenfunctions that are common to the groups to be classified. The density
ratios can then be factored into density ratios of individual functional
principal components whence the classification problem is reduced to a sequence
of nonparametric one-dimensional density estimates. This is an extension to
functional data of some of the very earliest nonparametric Bayes classifiers
that were based on simple density ratios in the one-dimensional case. By means
of the factorization of the density quotients the curse of dimensionality that
would otherwise severely affect Bayes classifiers for functional data can be
avoided. We demonstrate that in the case of Gaussian functional data, the
proposed functional Bayes classifier reduces to a functional version of the
classical quadratic discriminant. A study of the asymptotic behavior of the
proposed classifiers in the large sample limit shows that under certain
conditions the misclassification rate converges to zero, a phenomenon that has
been referred to as "perfect classification". The proposed classifiers also
perform favorably in finite sample applications, as we demonstrate in
comparisons with other functional classifiers in simulations and various data
applications, including wine spectral data, functional magnetic resonance
imaging (fMRI) data for attention deficit hyperactivity disorder (ADHD)
patients, and yeast gene expression data.


title: Two Cardinal Inequalities about Bidiscrete Systems

abstract:
  We consider the cardinal invariant $bd$ defined by M. D\v{z}amonja and I.
Juh\'asz concerning bidiscrete systems. Using the relation between bidiscrete
systems and irredundance for a compact Hausdorff space $K$, we prove that
${w(K)\leq bd(K)\cdot hL(K)^+}$, generalizing a result of S. Todorcevic
concerning the irredundance in Boolean algebras and we prove that for every
maximal irredundant family $\mathcal{F}\subset C(K)$, there is a $\pi$-base
$\mathcal{B}$ for $K$ with $|\mathcal{F}|=|\mathcal{B}|$, a result analogous to
the McKenzie Theorem for Boolean algebras in the context of compact spaces. In
particular, it is a consequence of the latter result that $\pi(K)\leq bd(K)$
for every compact Hausdorff space $K$. From the relation between bidiscrete
systems and biorthogonal systems, we obtain some results about biorthogonal
systems in Banach spaces of the form $C(K)$.


title:
Mobility-Aware Caching for Content-Centric Wireless Networks: Modeling
  and Methodology

abstract:
  As mobile services are shifting from "connection-centric" communications to
"content-centric" communications, content-centric wireless networking emerges
as a promising paradigm to evolve the current network architecture. Caching
popular content at the wireless edge, including base stations (BSs) and user
terminals (UTs), provides an effective approach to alleviate the heavy burden
on backhaul links, as well as lowering delays and deployment costs. In contrast
to wired networks, a unique characteristic of content-centric wireless networks
(CCWNs) is the mobility of mobile users. While it has rarely been considered by
existing works in caching design, user mobility contains various helpful side
information that can be exploited to improve caching efficiency at both BSs and
UTs. In this paper, we present a general framework on mobility-aware caching in
CCWNs. Key properties of user mobility patterns that are useful for content
caching will be firstly identified, and then different design methodologies for
mobility-aware caching will be proposed. Moreover, two design examples will be
provided to illustrate the proposed framework in details, and interesting
future research directions will be identified.


title: Topological Crystalline Transition Metals: Strained W, Ta, Mo, and Nb

abstract:
  In a joint theoretical and experimental investigation we show that a series
of transition metals with strained body-centered cubic lattice ---W, Ta, Nb,
and Mo--- host surface states that are topologically protected by mirror
symmetry. Our finding extends the class of topologically nontrivial systems by
topological crystalline transition metals. The investigation is based on
independent calculations of the electronic structures and of topological
invariants, the results of which agree with established properties of the
Dirac-type surface state in W(110). To further support our prediction, we
investigate both experimentally by spin-resolved inverse photoemission and
theoretically an unoccupied topologically nontrivial surface state in Ta(110).


title: Theory of charge density wave non-contact friction

abstract:
  A mechanism is proposed to describe the occurrence of distance-dependent
dissipation peaks in the dynamics of an atomic force microscope tip oscillating
over a surface characterized by a charge density wave state. The dissipation
has its origin in the hysteretic behavior of the tip oscillations occurring at
positions compatible with a localized phase slip of the charge density wave.
This model is supported through static and dynamic numerical simulations of the
tip surface interaction and is in good qualitative agreement with recently
performed experiments on a NbSe$_2$ sample.


title:
The Exceptional Aspects of the Confined X-class Flares of Solar Active
  Region 2192

abstract:
  During late October 2014, active region NOAA 2192 caused an unusual high
level of solar activity, within an otherwise weak solar cycle. While crossing
the solar disk, during a period of 11 days, it was the source of 114 flares of
GOES class C1.0 and larger, including 29 M- and 6 X-flares. Surprisingly, none
of the major flares (GOES class M5.0 and larger) was accompanied by a coronal
mass ejection, contrary to statistical tendencies found in the past. From
modeling the coronal magnetic field of NOAA 2192 and its surrounding, we
suspect that the cause of the confined character of the flares is the strong
surrounding and overlying large-scale magnetic field. Furthermore, we find
evidence for multiple magnetic reconnection processes within a single flare,
during which electrons were accelerated to unusual high energies.


title: CDW slips and giant frictional dissipation peaks at the NbSe$_2$ surface

abstract:
  Accessing, controlling and understanding nanoscale friction and dissipation
is a crucial issue in nanotechnology, where moving elements are central.
Recently, ultra-sensitive noncontact pendulum Atomic Force Microscope (AFM)
succeeded in detecting the electronic friction drop caused by the onset of
superconductivity in Nb, raising hopes that a wider variety of mechanisms of
mechanical dissipation arising from electron organization into different
collective phenomena will become accessible through this unconventional surface
probe. Among them, the driven phase dynamics of charge-density-waves (CDWs)
represents an outstanding challenge as a source of dissipation. Here we report
a striking multiplet of AFM dissipation peaks arising at nanometer distances
above the surface of NbSe$_2$ - a layered compound exhibiting an incommensurate
CDW. Each peak appears at a well defined tip-surface interaction force of the
order of a nN, and persists until T=70K where CDW short-range order is known to
disappear. A theoretical model is presented showing that the peaks are
connected to tip-induced local 2$\pi$ CDW phase slips. Under the attractive
potential of the approaching tip, the local CDW surface phase landscape deforms
continuously until a series of 2$\pi$ jumps occur between different values of
the local phase. As the tip oscillates to and fro, each slip gives rise to a
hysteresis cycle, appearing at a selected distance, the dissipation
corresponding to "pumping" in and out a local slip in the surface CDW phase of
NbSe$_2$.


title: The surprising dynamics of a chain on a pulley: Lift-off and snapping

abstract:
  The motion of weights attached to a chain or string moving on a frictionless
pulley is a classic problem of introductory physics used to understand the
relationship between force and acceleration. Here, we consider the dynamics of
the chain when one of the weights is removed and, thus, one end is pulled with
constant acceleration. This simple change has dramatic consequences for the
ensuing motion: at a finite time, the chain `lifts off' from the pulley and the
free end subsequently accelerates faster than the end that is pulled.
Eventually, the chain undergoes a dramatic reversal of curvature reminiscent of
the crack, or snap, of a whip. We combine experiments, numerical simulations,
and theoretical arguments to explain key aspects of this dynamical problem.


title: Dominant source of disorder in graphene: Charged impurities or ripples?

abstract:
  Experimentally produced graphene sheets exhibit a wide range of mobility
values. Both extrinsic charged impurities and intrinsic ripples (corrugations)
have been suggested to induce long-range disorder in graphene and could be a
candidate for the dominant source of disorder. Here, using large-scale
molecular dynamics and quantum transport simulations, we find that the hopping
disorder and the gauge and scalar potentials induced by the ripples are
short-ranged, in strong contrast with predictions by continuous models, and the
transport fingerprints of the ripple disorder are very different from those of
charged impurities. We conclude that charged impurities are the dominant source
of disorder in most graphene samples, whereas scattering by ripples is mainly
relevant in the high carrier density limit of ultraclean graphene samples (with
a charged impurity concentration < 10 ppm) at room and higher temperatures.


title: A variational model for anisotropic and naturally twisted ribbons

abstract:
  We consider thin plates whose energy density is a quadratic function of the
difference between the second fundamental form of the deformed configuration
and a "natural" curvature tensor. This tensor either denotes the second
fundamental form of the stress-free configuration, if it exists, or a target
curvature tensor. In the latter case, residual stress arises from the
geometrical frustration involved in the attempt to achieve the target
curvature: as a result, the plate is naturally twisted, even in the absence of
external forces or prescribed boundary conditions. Here, starting from this
kind of plate energies, we derive a new variational one-dimensional model for
naturally twisted ribbons by means of Gamma-convergence. Our result
generalizes, and corrects, the classical Sadowsky energy to geometrically
frustrated anisotropic ribbons with a narrow, possibly curved, reference
configuration.


title:
On the involution of the real line induced by Dyer's outer automorphism
  of PGL(2,Z)

abstract:
  We study the involution of the real line induced by the outer automorphism of
the extended modular group PGL(2,Z). This `modular' involution is discontinuous
at rationals but satisfies a surprising collection of functional equations. It
preserves the set of real quadratic irrationals mapping them in a non-obvious
way to each other. It commutes with the Galois action on real quadratic
irrationals. More generally, it preserves set-wise the orbits of the modular
group, thereby inducing an involution of the moduli space of real rank-two
lattices. We give a description of this involution as the boundary action of a
certain automorphism of the infinite trivalent tree. It is conjectured that
algebraic numbers of degree at least three are mapped to transcendental numbers
under this involution.


title: Improved Image Boundaries for Better Video Segmentation

abstract:
  Graph-based video segmentation methods rely on superpixels as starting point.
While most previous work has focused on the construction of the graph edges and
weights as well as solving the graph partitioning problem, this paper focuses
on better superpixels for video segmentation. We demonstrate by a comparative
analysis that superpixels extracted from boundaries perform best, and show that
boundary estimation can be significantly improved via image and time domain
cues. With superpixels generated from our better boundaries we observe
consistent improvement for two video segmentation methods in two different
datasets.


title: Distributed Testing of Excluded Subgraphs

abstract:
  We study property testing in the context of distributed computing, under the
classical CONGEST model. It is known that testing whether a graph is
triangle-free can be done in a constant number of rounds, where the constant
depends on how far the input graph is from being triangle-free. We show that,
for every connected 4-node graph H, testing whether a graph is H-free can be
done in a constant number of rounds too. The constant also depends on how far
the input graph is from being H-free, and the dependence is identical to the
one in the case of testing triangles. Hence, in particular, testing whether a
graph is K_4-free, and testing whether a graph is C_4-free can be done in a
constant number of rounds (where K_k denotes the k-node clique, and C_k denotes
the k-node cycle). On the other hand, we show that testing K_k-freeness and
C_k-freeness for k>4 appear to be much harder. Specifically, we investigate two
natural types of generic algorithms for testing H-freeness, called DFS tester
and BFS tester. The latter captures the previously known algorithm to test the
presence of triangles, while the former captures our generic algorithm to test
the presence of a 4-node graph pattern H. We prove that both DFS and BFS
testers fail to test K_k-freeness and C_k-freeness in a constant number of
rounds for k>4.


title: Deformable Parts Correlation Filters for Robust Visual Tracking

abstract:
  Deformable parts models show a great potential in tracking by principally
addressing non-rigid object deformations and self occlusions, but according to
recent benchmarks, they often lag behind the holistic approaches. The reason is
that potentially large number of degrees of freedom have to be estimated for
object localization and simplifications of the constellation topology are often
assumed to make the inference tractable. We present a new formulation of the
constellation model with correlation filters that treats the geometric and
visual constraints within a single convex cost function and derive a highly
efficient optimization for MAP inference of a fully-connected constellation. We
propose a tracker that models the object at two levels of detail. The coarse
level corresponds a root correlation filter and a novel color model for
approximate object localization, while the mid-level representation is composed
of the new deformable constellation of correlation filters that refine the
object location. The resulting tracker is rigorously analyzed on a highly
challenging OTB, VOT2014 and VOT2015 benchmarks, exhibits a state-of-the-art
performance and runs in real-time.


title: Cross-diffusion systems for image processing: II. The nonlinear case

abstract:
  In this paper the use of nonlinear cross-diffu\-sion systems to model image
restoration is investigated, theoretically and numerically. In the first case,
well-posedness, scale-space properties and long time behaviour are analyzed.
From a numerical point of view, a computational study of the performance of the
models is carried out, suggesting their diversity and potentialities to treat
image filtering problems. The present paper is a continuation of a previous
work of the same authors, devoted to linear cross-diffusion models.
\keywords{Cross-diffusion \and Complex diffusion \and Image restoration}


title: On the Jensen functional and superterzaticity

abstract:
  In this note we describe some results concerning upper and lower bounds for
the Jensen functional. We use several known and new results to shed light on
the concepts of superterzatic functions.


title:
A Selective Metasurface Absorber with An Amorphous Carbon Interlayer for
  Solar Thermal Applications

abstract:
  This paper presents fabrication, measurement and modelling results for a
metal-dielectric-metal metasurface absorber for solar thermal applications. The
structure uses amorphous carbon as an inter-layer between thin gold films with
the upper film patterned with a 2D periodic array using focused ion beam
etching. The patterned has been optimised to give high absorptance from
400-1200nm and low absorptance above this wavelength range to minimise thermal
radiation and hence obtain higher temperature performance. Wide angle
absorptance results are shown and detailed modelling of a realistic
nanostructured upper layer results in excellent agreement between measured and
modelled results. The use of gold in this paper is a first step towards a high
temperature metasurface where gold can be replaced by other refractory metals
such as tungsten or chrome.


title:
Sub-vector Extraction and Cascade Post-Processing for Speaker
  Verification Using MLLR Super-vectors

abstract:
  In this paper, we propose a speaker-verification system based on maximum
likelihood linear regression (MLLR) super-vectors, for which speakers are
characterized by m-vectors. These vectors are obtained by a uniform
segmentation of the speaker MLLR super-vector using an overlapped sliding
window. We consider three approaches for MLLR transformation, based on the
conventional $1$-best automatic transcription, on the lattice word
transcription, or on a simple global universal background model (UBM). Session
variability compensation is performed in a post-processing module with
probabilistic linear discriminant analysis (PLDA) or the eigen factor radial
(EFR). Alternatively, we propose a cascade post-processing for the MLLR
super-vector based speaker-verification system.
  In this case, the m-vectors or MLLR super-vectors are first projected onto a
lower-dimensional vector space generated by linear discriminant analysis (LDA).
Next, PLDA session variability compensation and scoring is applied to the
reduced-dimensional vectors. This approach combines the advantages of both
techniques and makes the estimation of PLDA parameters easier. Experimental
results on telephone conversations of the NIST 2008 and 2010 speaker
recognition evaluation (SRE) indicate that the proposed m-vector system
performs significantly better than the conventional system based on the full
MLLR super-vectors. Cascade post-processing further reduces the error rate in
all cases. Finally, we present the results of fusion with a standard i-vector
system in the feature, as well as in the score domain, demonstrating that the
m-vector system is both competitive and complementary with it.


title: Near isotropic behaviour of turbulent thermal convection

abstract:
  We investigate the anisotropy in turbulent convection in a 3D box using
direct numerical simulation. We compute the anisotropic parameter $A =
u_\perp^{2}/(2u_{\parallel}^{2})$, where $u_{\perp}$ and $u_{\parallel}$ are
the components of velocity perpendicular and parallel to the buoyancy
direction, the shell and ring spectra, and shell-to-shell energy transfers. We
observe that the flow is nearly isotropic for the Prandtl number $\mathrm{Pr}
\approx 1$, but the anisotropy increases with the Prandtl number. For
$\mathrm{Pr}=\infty$, $A \approx 0.3$, thus anisotropy is not very significant
even in extreme cases. We also observe that $u_{\parallel}$ feeds energy to
$u_{\perp}$ via pressure. The computation of shell-to-shell energy transfers
reveals that the energy transfer in turbulent convection is local and forward,
similar to hydrodynamic turbulence. These results are consistent with the
Kolmogorov's spectrum observed by Kumar et al.~[Phys. Rev. E {\bf 90}, 023016
(2014)] for turbulent convection.


title:
pSpatiocyte: A Parallel Stochastic Method for Particle
  Reaction-Diffusion Systems

abstract:
  Computational systems biology has provided plenty of insights into cell
biology. Early on, the focus was on reaction networks between molecular
species. Spatial distribution only began to be considered mostly within the
last decade. However, calculations were restricted to small systems because of
tremendously high computational workloads. To date, application to the cell of
typical size with molecular resolution is still far from realization. In this
article, we present a new parallel stochastic method for particle
reaction-diffusion systems. The program called pSpatiocyte was created bearing
in mind reaction networks in biological cells operating in crowded
intracellular environments as the primary simulation target. pSpatiocyte
employs unique discretization and parallelization algorithms based on a
hexagonal close-packed lattice for efficient execution particularly on large
distributed memory parallel computers. For two-level parallelization, we
introduced isolated subdomain and tri-stage lockstep communication for
process-level, and voxel-locking techniques for thread-level. We performed a
series of parallel runs on RIKEN's K computer. For a fine lattice that had
relatively low occupancy, pSpatiocyte achieved 7686 times speedup with 663552
cores relative to 64 cores from the viewpoint of strong scaling and exhibited
74\% parallel efficiency. As for weak scaling, efficiencies at least 60% were
observed up to 663552 cores. In addition to computational performance,
diffusion and reaction rates were validated by theory and another
well-validated program and had good agreement. Lastly, as a preliminary example
of real-world applications, we present a calculation of the MAPK model, a
typical reaction network motif in cell signaling pathways.


title: VSI electromagnetic fields

abstract:
  A $p$-form $F$ is VSI (i.e., all its scalar invariants of arbitrary order
vanish) in a $n$-dimensional spacetime if and only if it is of type N, its
multiple null direction $l$ is "degenerate Kundt", and $\pounds_{l}F=0$. This
recent result is reviewed in the present contribution and its main consequences
are summarized. In particular, a subset of VSI Maxwell fields possesses a
universal property, i.e., they also solve (virtually) any generalized
(non-linear and with higher derivatives) electrodynamics, possibly also coupled
to Einstein's gravity.


title: From cylindrical to stretching ridges and wrinkles in twisted ribbons

abstract:
  Twisted ribbons subjected to a tension exhibit a remarkably rich morphology,
from smooth and wrinkled helicoids, to cylindrical or faceted patterns. These
shapes are intimately related to the instability of the natural, helicoidal
symmetry of the system, which generates both longitudinal and transverse
stresses, thereby leading to buckling of the ribbon. In this paper, we focus on
the tessellation patterns made of triangular facets. Our experimental
observations are described within an "asymptotic isometry" approach that brings
together geometry and elasticity. The geometry consists of parametrized
families of surfaces, isometric to the undeformed ribbon in the singular limit
of vanishing thickness and tensile load. The energy, whose minimization selects
the favored structure among those families, is governed by the tensile work and
bending cost of the pattern. This framework describes the coexistence lines in
a morphological phase diagram, and determines the domain of existence of
faceted structures.


title:
Towards detecting methanol emission in low-mass protoplanetary discs
  with ALMA: The role of non-LTE excitation

abstract:
  The understanding of organic content of protoplanetary discs is one of the
main goals of the planet formation studies. As an attempt to guide the
observational searches for weak lines of complex species in discs, we modelled
the (sub-)millimetre spectrum of gaseous methanol (CH$_3$OH), one of the
simplest organic molecules, in the representative T Tauri system. We used 1+1D
disc physical model coupled to the gas-grain ALCHEMIC chemical model with and
without 2D-turbulent mixing. The computed CH$_3$OH abundances along with the
CH$_3$OH scheme of energy levels of ground and excited torsional states were
used to produce model spectra obtained with the non-local thermodynamic
equilibrium (non-LTE) 3D line radiative transfer code LIME. We found that the
modelled non-LTE intensities of the CH$_3$OH lines can be lower by factor of
$>10$--$100$ than those calculated under assumption of LTE. Though population
inversion occurs in the model calculations for many (sub-)millimetre
transitions, it does not lead to the strong maser amplification and noticeably
high line intensities. We identify the strongest CH$_3$OH (sub-)millimetre
lines that could be searched for with the Atacama Large Millimeter Array (ALMA)
in nearby discs. The two best candidates are the CH$_{3}$OH $5_0-4_0~A^+$
(241.791 GHz) and $5_{-1}-4_{-1}~E$ (241.767 GHz) lines, which could possibly
be detected with the $\sim5\sigma$ signal-to-noise ratio after $\sim3$ hours of
integration with the full ALMA array.


title: Robust and Globally Optimal Manhattan Frame Estimation in Near Real Time

abstract:
  Most man-made environments, such as urban and indoor scenes, consist of a set
of parallel and orthogonal planar structures. These structures are approximated
by the Manhattan world assumption, in which notion can be represented as a
Manhattan frame (MF). Given a set of inputs such as surface normals or
vanishing points, we pose an MF estimation problem as a consensus set
maximization that maximizes the number of inliers over the rotation search
space. Conventionally, this problem can be solved by a branch-and-bound
framework, which mathematically guarantees global optimality. However, the
computational time of the conventional branch-and-bound algorithms is rather
far from real-time. In this paper, we propose a novel bound computation method
on an efficient measurement domain for MF estimation, i.e., the extended
Gaussian image (EGI). By relaxing the original problem, we can compute the
bound with a constant complexity, while preserving global optimality.
Furthermore, we quantitatively and qualitatively demonstrate the performance of
the proposed method for various synthetic and real-world data. We also show the
versatility of our approach through three different applications: extension to
multiple MF estimation, 3D rotation based video stabilization, and vanishing
point estimation (line clustering).


title: Pulse Shaped OFDM for 5G Systems

abstract:
  OFDM-based waveforms with filtering or windowing functionalities are
considered key enablers for a flexible air-interface design for multi-service
support in future 5G systems. One candidate from this category of waveforms is
pulse shaped OFDM, which follows the idea of subcarrier filtering and aims at
fully maintaining the advantages of standard OFDM systems while addressing
their drawbacks. In this paper, we elaborate on several pulse shaping design
methods, and show how pulse shapes can be exploited as an additional degree of
freedom to provide better frequency localization and more efficient spectrum
utilization under a pre-defined spectrum mask. The performance analysis and
evaluation results show that, for a practical mobile communication systems, the
application of pulse shaping is a simple and effective means to achieve a lower
out-of-band leakage for OFDM systems at virtually no costs. In fact, the
complexity increase amounts to 1-2% compared to CP-OFDM only. In addition, the
system's robustness against both time and frequency distortions is shown to be
substantially improved by a proper pulse shape design. By allowing for the
flexible configuration of physical layer parameters per sub-band according to
the diverse requirements of future 5G services, pulse shaped OFDM systems can
efficiently facilitate asynchronous transmissions and fragmented spectrum
access, rendering it beneficial for various mobile-broadband and
Internet-of-Things applications.


title:
Examining the relationships between colour, $T_{\rm eff}$, and [M/H] for
  APOGEE K and M dwarfs

abstract:
  We present the effective temperatures ($T_{\rm eff}$), metallicities, and
colours in SDSS, 2MASS, and WISE filters, of a sample of 3834 late-K and
early-M dwarfs selected from the Sloan Digital Sky Survey APOGEE spectroscopic
survey ASPCAP catalog. We confirm that ASPCAP $T_{\rm eff}$ values between 3550
K$<T_{\rm eff}<$4200 K are accurate to $\sim$100 K compared to interferometric
$T_{\rm eff}$ values. In that same $T_{\rm eff}$ range, ASPCAP metallicities
are accurate to 0.18 dex between $-1.0<$[M/H]$<0.2$. For these cool dwarfs,
nearly every colour is sensitive to both $T_{\rm eff}$ and metallicity.
Notably, we find that $g-r$ is not a good indicator of metallicity for
near-solar metallicity early-M dwarfs. We confirm that $J-K_S$ colour is
strongly dependent on metallicity, and find that $W1-W2$ colour is a promising
metallicity indicator. Comparison of the late-K and early-M dwarf colours,
metallicities, and $T_{\rm eff}$ to those from three different model grids
shows reasonable agreement in $r-z$ and $J-K_S$ colours, but poor agreement in
$u-g$, $g-r$, and $W1-W2$. Comparison of the metallicities of the KM dwarf
sample to those from previous colour-metallicity relations reveals a lack of
consensus in photometric metallicity indicators for late-K and early-M dwarfs.
We also present empirical relations for $T_{\rm eff}$ as a function of $r-z$
colour combined with either [M/H] or $W1-W2$ colour, and for [M/H] as a
function of $r-z$ and $W1-W2$ colour. These relations yield $T_{\rm eff}$ to
$\sim$100 K and [M/H] to $\sim$0.18 dex precision with colours alone, for
$T_{\rm eff}$ in the range of 3550-4200 K and [M/H] in the range of $-$0.5-0.2.


title:
Kernel-based system identification from noisy and incomplete
  input-output data

abstract:
  In this contribution, we propose a kernel-based method for the identification
of linear systems from noisy and incomplete input-output datasets. We model the
impulse response of the system as a Gaussian process whose covariance matrix is
given by the recently introduced stable spline kernel. We adopt an empirical
Bayes approach to estimate the posterior distribution of the impulse response
given the data. The noiseless and missing data samples, together with the
kernel hyperparameters, are estimated maximizing the joint marginal likelihood
of the input and output measurements. To compute the marginal-likelihood
maximizer, we build a solution scheme based on the Expectation-Maximization
method. Simulations on a benchmark dataset show the effectiveness of the
method.


title:
Ultra-Flat Galaxies Selected from RFGC Catalog. II. Orbital Estimates of
  Halo Masses

abstract:
  We used the Revised Flat Galaxy Catalog (RFGC) to select 817 ultra-flat (UF)
edge-on disk galaxies with blue and red apparent axial ratios of $(a/b)_B >
10.0$ and $(a/b)_R > 8.5$. The sample covering the whole sky, except the Milky
Way zone, contains 490 UF galaxies with measured radial velocities. Our
inspection of the neighboring galaxies around them revealed only 30 companions
with radial velocity difference of $\mid\Delta V\mid<500$ km s$^{-1}$ inside
the projected separation of $R_p < 250$ kpc. Wherein, the wider area around the
UF galaxy within $R_p < 750$ kpc contains no other neighbors brighter than the
UF galaxy itself in the same velocity span. The resulting sample galaxies
mostly belong to the morphological types Sc, Scd, Sd. They have a moderate
rotation velocity curve amplitude of about $120$ km s$^{-1}$ and a moderate
K-band luminosity of about $10^{10}L_{\odot}$. The median difference of radial
velocities of their companions is $87$ km s$^{-1}$, yielding the median orbital
mass estimate of about $5\times10^{11}M_{\odot}$. Excluding six probable
non-isolated pairs, we obtained a typical halo-mass-to-stellar-mass of UF
galaxies of about $30$, what is almost the same one as in the principal spiral
galaxies, like M 31 and M 81 in the nearest groups. We also note that
ultra-flat galaxies look two times less "dusty" than other spirals of the same
luminosity.


title: A Note on Alternating Links and Root Polytopes

abstract:
  In this paper, a relationship between the determinant of an alternating link
and a certain polytope obtained from the link diagram is analyzed. We also show
that when the underlying graph of the link diagram is properly oriented, the
number of its spanning arborescence is equal to the determinant, i.e., the
value at -1 of the Jones polynomial.


title:
Double ramification cycles and the $n$-point function for the moduli
  space of curves

abstract:
  In this paper, using the formula for the integrals of the $\psi$-classes over
the double ramification cycles found by S. Shadrin, L. Spitz, D. Zvonkine and
the author, we derive a new explicit formula for the $n$-point function of the
intersection numbers on the moduli space of curves.


title: Asymptotical properties of distributions of isotropic L\' evy processes

abstract:
  In this paper, we establish the precise asymptotic behaviors of the tail
probability and the transition density of a large class of isotropic L\'evy
processes when the scaling order is between 0 and 2 including 2. We also obtain
the precise asymptotic behaviors of the tail probability of subordinators when
the scaling order is between 0 and 1 including 1.
  The asymptotic expressions are given in terms of the radial part of
characteristic exponent $\psi$ and its derivative. In particular, when
$\psi(\lambda)-\frac{\lambda}{2}\psi'(\lambda)$ varies regularly, as
$\frac{t\psi(r^{-1})^2}{\psi(r^{-1})-(2r)^{-1}\psi'(r^{-1})} \to 0$ the tail
probability $\mathbb{P}(|X_t|\geq r)$ is asymptotically equal to a constant
times $ t( \psi(r^{-1})-(2r)^{-1}\psi'(r^{-1})).$


title:
Incremental and Parallel Machine Learning Algorithms with Automated
  Learning Rate Adjustments

abstract:
  The existing machine learning algorithms for minimizing the convex function
over a closed convex set suffer from slow convergence because their learning
rates must be determined before running them. This paper proposes two machine
learning algorithms incorporating the line search method, which automatically
and algorithmically finds appropriate learning rates at run-time. One algorithm
is based on the incremental subgradient algorithm, which sequentially and
cyclically uses each of the parts of the objective function; the other is based
on the parallel subgradient algorithm, which uses parts independently in
parallel. These algorithms can be applied to constrained nonsmooth convex
optimization problems appearing in tasks of learning support vector machines
without adjusting the learning rates precisely. The proposed line search method
can determine learning rates to satisfy weaker conditions than the ones used in
the existing machine learning algorithms. This implies that the two algorithms
are generalizations of the existing incremental and parallel subgradient
algorithms for solving constrained nonsmooth convex optimization problems. We
show that they generate sequences that converge to a solution of the
constrained nonsmooth convex optimization problem under certain conditions. The
main contribution of this paper is the provision of three kinds of experiment
showing that the two algorithms can solve concrete experimental problems faster
than the existing algorithms. First, we show that the proposed algorithms have
performance advantages over the existing ones in solving a test problem.
Second, we compare the proposed algorithms with a different algorithm Pegasos,
which is designed to learn with a support vector machine efficiently, in terms
of prediction accuracy, value of the objective function, and computational
time. Finally, we use...


title:
Cluster Mean-Field Signature of Entanglement Entropy in Bosonic
  Superfluid-Insulator Transitions

abstract:
  Entanglement entropy (EE), a fundamental conception in quantum information
for characterizing entanglement, has been extensively employed to explore
quantum phase transitions (QPTs). Although the conventional single-site
mean-field (MF) approach successfully predicts the emergence of QPTs, it fails
to include any entanglement. Here, for the first time, in the framework of a
cluster MF treatment, we extract the signature of EE in the bosonic
superfluid-insulator transitions. We consider a trimerized Kagome lattice of
interacting bosons, in which each trimer is treated as a cluster, and implement
the cluster MF treatment by decoupling all inter-trimer hopping. In addition to
superfluid and integer insulator phases, we find that fractional insulator
phases appear when the tunneling is dominated by the intra-trimer part. To
quantify the residual bipartite entanglement in a cluster, we calculate the
second-order Renyi entropy, which can be experimentally measured by quantum
interference of many-body twins. The second-order Renyi entropy itself is
continuous everywhere, however, the continuousness of its first-order
derivative breaks down at the phase boundary. This means that the bosonic
superfluid-insulator transitions can still be efficiently captured by the
residual entanglement in our cluster MF treatment. Besides to the bosonic
superfluid-insulator transitions, our cluster MF treatment may also be used to
capture the signature of EE for other QPTs in quantum superlattice models.


title:
Chiral and deconfinement phase transition in the Hamiltonian approach to
  QCD in Coulomb gauge

abstract:
  The chiral and deconfinement phase transitions are investigated within the
variational Hamiltonian approach to QCD in Coulomb gauge. The temperature
$\beta^{- 1}$ is introduced by compactifying a spatial dimension. Thereby the
whole temperature dependence is encoded in the vacuum state on the spatial
manifold $\mathbb{R}^2 \times S^1 (\beta)$. The chiral quark condensate and the
dual quark condensate (dressed Polyakov loop) are calculated as function of the
temperature. From their inflection points the pseudo-critical temperatures for
the chiral and deconfinement crossover transitions are determined. Using the
zero-temperature quark and gluon propagators obtained within the variational
approach as input, we find $168 \, \mathrm{MeV}$ and $196 \, \mathrm{MeV}$,
respectively, for the chiral and deconfinement transition.


title:
Citation distribution of individual scientist: approximations of stretch
  exponential distribution with power law tails

abstract:
  A multi-parametric family of stretch exponential distributions with various
power law tails is introduced and is shown to describe adequately the empirical
distributions of scientific citation of individual authors. The four-parametric
families are characterized by a normalization coefficient in the exponential
part, the power exponent in the power-law asymptotic part, and the coefficient
for the transition between the above two parts. The distribution of papers of
individual scientist over citations of these papers is studied. Scientists are
selected via total number of citations in three ranges: 102-103, 103-104, and
104-105 of total citations. We study these intervals for physicists in ISI Web
of Knowledge. The scientists who started their scientific publications after
1980 were taken into consideration only. It is detected that the power
coefficient in the stretch exponent starts from one for low-cited authors and
has to trend to smaller values for scientists with large number of citation. At
the same time, the power coefficient in tail drops for large-cited authors. One
possible explanation for the origin of the stretch-exponential distribution for
citation of individual author is done.


title:
Harbingers and latecomers - The order of appearance of exact coherent
  structures in plane Poiseuille flow

abstract:
  The transition to turbulence in plane Poiseuille flow (PPF) is connected with
the presence of exact coherent structures. In contrast to other shear flows,
PPF has a number of different coherent states that are relevant for the
transition. We here discuss the different states, compare the critical Reynolds
numbers and optimal wavelengths for their appearance, and explore the
differences between flows operating at constant mass flux or at constant
pressure drop. The Reynolds numbers quoted here are based on the mean flow
velocity and refer to constant mass flux, the ones for constant pressure drop
are always higher. The Tollmien-Schlichting waves bifurcate subcritically from
the laminar profile at $Re=5772$ and reach down to $Re=2609$ (at a different
optimal wave length). Their localized counter part bifurcates at the even lower
value $Re=2334$. Three dimensional exact solutions appear at much lower
Reynolds numbers. We describe one exact solutions that is spanwise localized
and has a critical Reynolds number of $316$. Comparison to plane Couette flow
suggests that this is likely the lowest Reynolds number for exact coherent
structures in PPF. Streamwise localized versions of this state require higher
Reynolds numbers, with the lowest bifurcation occurring near $Re=1018$.