title:
Physical interpretation of the spectral approach to delocalization in
  infinite disordered systems

abstract:
  In this paper we introduce the spectral approach to delocalization in
infinite disordered systems and provide a physical interpretation in context of
the classical model of Edwards and Thouless. We argue that spectral analysis is
an important contribution to localization problems since it avoids issues
related to the use of boundary conditions. Applying the method to 2D and 3D
numerical simulations with various amount of disorder W shows that
delocalization occurs for W<=0.6 in 2D and for W<=5 for 3D.


title:
A Quantitative Study of the Effect of Cladding Thickness on Modal
  Confinement Loss in Photonic Waveguides

abstract:
  There has been increasing interest in making the photonic devices more and
more compact in the integrated photonics industry, and one of the important
questions for manufacturers and design engineers is how to quantify the effect
of the finite cladding thickness on the modal confinement loss of photonic
waveguides. This requires at least six to seven digits accuracy for the
computation of propagation constant $\beta$ since the modal confinement loss is
proportional to the imaginary part of $\beta$ that is six to seven orders of
magnitude smaller than its real part by the industrial standard. In this paper,
we present an accurate and efficient method to compute the propagation constant
of electromagnetic modes of photonic waveguides with arbitrary number of
(nonsmooth) inclusions in a layered media. The method combines a
well-conditioned boundary integral equation formulation for photonic waveguides
which requires the discretization of the material interface only, and efficient
Sommerfeld integral representations to treat the effect of the layered medium.
Our scheme is capable of calculating the propagation loss of the
electromagnetic modes with high fidelity, even for waveguides with corners
imbedded in a cladding material of finite thickness. The numerical results,
with more than $10$-digit accuracy, show quantitatively that the modal
confinement loss of the rectangular waveguide increases exponentially fast as
the cladding thickness decreases.


title: The polarization of light and the Malus' law using smartphones

abstract:
  Originally an empirical law, nowadays Malus' law is seen as a key experiment
to demonstrate the transverse nature of electromagnetic waves, as well as the
intrinsic connection between optics and electromagnetism. In this work, a
simple and inexpensive setup is proposed to quantitatively verify the nature of
polarized light. A flat computer screen serves as a source of linear polarized
light and a smartphone (possessing ambient light and orientation sensors) is
used, thanks to its built-in sensors, to experiment with polarized light and
verify the Malus' law.


title: Augmenting Supervised Emotion Recognition with Rule-Based Decision Model

abstract:
  The aim of this research is development of rule based decision model for
emotion recognition. This research also proposes using the rules for augmenting
inter-corporal recognition accuracy in multimodal systems that use supervised
learning techniques. The classifiers for such learning based recognition
systems are susceptible to over fitting and only perform well on intra-corporal
data. To overcome the limitation this research proposes using rule based model
as an additional modality. The rules were developed using raw feature data from
visual channel, based on human annotator agreement and existing studies that
have attributed movement and postures to emotions. The outcome of the rule
evaluations was combined during the decision phase of emotion recognition
system. The results indicate rule based emotion recognition augment recognition
accuracy of learning based systems and also provide better recognition rate
across inter corpus emotion test data.


title: A Geometric Approach to Hochschild Cohomology of the Exterior Algebra

abstract:
  We give a new computation of Hochschild (co)homology of the exterior algebra,
together with algebraic structures, by direct comparison with the symmetric
algebra. The Hochschild cohomology is determined to be essentially the algebra
of even-weight polyvector fields. From Kontsevich's formality theorem, the
differential graded Lie algebra of Hochschild cochains is proved to be formal
when the vector space generating the exterior algebra is even dimensional. We
conjecture that formality fails in the odd dimensional case, proving this when
the dimension is one. In all dimensions, formal deformations of the exterior
algebra are classified by formal Poisson structures.


title:
The aggregate path coupling method for the Potts model on bipartite
  graph

abstract:
  In this paper, we derive the large deviations principle for the Potts model
on the complete bipartite graph $K_{n,n}$ as $n$ increases to infinity. Next,
for the Potts model on $K_{n,n}$, we provide an extension of the method of
aggregate path coupling that was originally developed in Kovchegov et al 2011
for the mean-field Blume-Capel model and in Kovchegov and Otto 2015 for a
general mean-field setting that included the Generalized Curie-Weiss-Potts
model analyzed in Cuff et al 2012. We use the aggregate path coupling method to
identify and prove the interface value $\beta_s$ separating the rapid and slow
mixing regimes for the Glauber dynamics of the Potts model on $K_{n,n}$.


title:
Similarity of Jet Radiation between Flat Spectrum Radio Quasars and GeV
  Narrow-Line Seyfert 1 Galaxies: A Universal $\delta$-$L_{\rm c}$ Correlation

abstract:
  By modeling the broadband spectral energy distributions (SEDs) of a typical
flat spectrum radio quasar (FSRQ, 3C 279) and two GeV narrow-line Seyfert 1
galaxies (NLS1s, PMN J0948+0022 and 1H 0323+342) in different flux stages with
the one-zone leptonic models, we find a universal correlation between their
Doppler factors ($\delta$) and peak luminosities ($L_{\rm c}$) of external
Compton scattering bumps. Compiling a combined sample of FSRQs and GeV NLS1s,
it is found that both FSRQs and GeV NLS1s in different stages and in different
sources well follow the same $\delta$-$L_{\rm c}$ correlation. This indicates
that the variations of observed luminosities may be essentially due to the
Doppler boosting effect. And the universal $\delta$-$L_{\rm c}$ relation
between FSRQs and GeV NLS1s in different stages may be further evidence that
the particle acceleration and radiation mechanisms for the two kinds of sources
are similar. In addition, by replacing $L_{\rm c}$ with the observed luminosity
in the Fermi/LAT band ($L_{\rm LAT}$), this correlation holds, and it may serve
as an empirical indicator of $\delta$. We estimate the $\delta$ values with
$L_{\rm LAT}$ for 484 FSRQs in the Fermi/LAT Catalog and they range from 3 to
41, with a median of 16, which are statistically consistent with the values
derived by other methods.


title:
X-ray Background at High Redshifts from Pop III Remnants: Results from
  Pop III star formation rates in the Renaissance Simulations

abstract:
  Due to their long mean free paths, X-rays are expected to have many
significant impacts globally on the properties of the intergalactic medium
(IGM) by their heating and ionizing processes on large scales. At high
redshifts, X-rays from Population (Pop) III binaries might have important
effects on cosmic reionization and the Lyman alpha forest. As a continuation of
our previous work on Pop III binary X-rays (Xu et al. 2014), we use the Pop III
distribution and evolution from the Renaissance Simulations, a suite of
self-consistent cosmological radiation hydrodynamics simulations of the
formation of the first galaxies, to calculate the X-ray luminosity density and
background over the redshift range 20 > z > 7.6. As we find that Pop III star
formation continues at a low, nearly constant rate to the end of reionization,
X-rays are being continuously produced at significant rates compared to other
possible X-ray sources, such as AGNs and normal X-ray binaries during the same
period of time. We estimate that Pop III binaries produce approximately 6 eV of
energy in the X-rays per hydrogen atom. We calculate the X-ray background for
different monochromatic photon energies. KeV X-rays redshift and accumulate to
produce a strong X-ray background spectrum extending to roughly 500 eV. The
X-ray background is strong enough to heat the IGM to ~ 1000 K and to ionize a
few percent of the neutral hydrogen. These effects are important for an
understanding of the neutral hydrogen hyperfine transition 21-cm line
signatures, the Ly alpha forest, and optical depth of the CMB to Thomson
scattering.


title: Classifier Risk Estimation under Limited Labeling Resources

abstract:
  In this paper we propose strategies for estimating performance of a
classifier when labels cannot be obtained for the whole test set. The number of
test instances which can be labeled is very small compared to the whole test
data size. The goal then is to obtain a precise estimate of classifier
performance using as little labeling resource as possible. Specifically, we try
to answer, how to select a subset of the large test set for labeling such that
the performance of a classifier estimated on this subset is as close as
possible to the one on the whole test set. We propose strategies based on
stratified sampling for selecting this subset. We show that these strategies
can reduce the variance in estimation of classifier accuracy by a significant
amount compared to simple random sampling (over 65% in several cases). Hence,
our proposed methods are much more precise compared to random sampling for
accuracy estimation under restricted labeling resources. The reduction in
number of samples required (compared to random sampling) to estimate the
classifier accuracy with only 1% error is high as 60% in some cases.


title:
Universality classes of order parameters composed of many body bound
  states

abstract:
  This theoretical paper discusses microscopic models giving rise to special
types of order in which conduction electrons are bound together with localized
spins to create composite order parameters. It is shown that composite order is
related to the formation of a spin liquid with gapped excitations carrying
quantum numbers which are a fraction of those of electron. These spin liquids
are special in the sense that their formation necessarily involves spin degrees
of freedom of both the conduction and the localized electrons. A detailed
description of such spin liquid states is presented with a special emphasize on
a demonstration of their robustness against local perturbations preserving the
Lie group symmetry and the translational invariance.


title: Improved Classical and Quantum Random Access Codes

abstract:
  A (Quantum) Random Access Code ((Q)RAC) is a scheme that encodes $n$ bits
into $m$ (qu)bits such that any of the $n$ bits can be recovered with a worst
case probability $p>\frac{1}{2}$. Such a code is denoted by the triple
$(n,m,p)$. It is known that $n<4^m$ for all QRACs and $n<2^m$ for classical
RACs. These bounds are also known to be tight, as explicit constructions exist
for $n=4^m-1$ and $n=2^m-1$ for quantum and classical codes respectively. We
generalize (Q)RACs to a scheme encoding $n$ $d$-levels into $m$ (qu)-$d$-levels
such that any $d$-level can be recovered with the probability for every wrong
outcome value being less than $\frac{1}{d}$. We construct explicit solutions
for all $n\leq \frac{d^{2m}-1}{d-1}$. For $d=2$, the constructions coincide
with those previously known. We show that the (Q)RACs are $d$-parity-oblivious,
generalizing ordinary parity-obliviousness. We further investigate optimization
of the success probabilities. For $d=2$, we use the measure operators of the
previously best known solutions, but improve the encoding states to give a
higher success probability. We conjecture that for maximal $(n=4^m-1,m,p)$
QRACs, $p=\frac{1+\frac{1}{(\sqrt{3}+1)^m-1}}{2}$ is possible and show that it
is an upper bound for the measure operators that we use. When we compare
$(n,m,p_q)$ QRACs with classical $(n,2m,p_c)$ RACs, we can always find $p_q\geq
p_c$, but the classical code gives information about every input bit
simultaneously, while the QRAC only gives information about a subset. For
several different $(n,2,p)$ QRACs, we see the same trade-off, as the best $p$
values are obtained when the number of bits that can be obtained simultaneously
is as small as possible. The trade-off is connected to parity-obliviousness,
since high certainty information about several bits can be used to calculate
probabilities for parities of subsets.


title:
Optimal Joint Power and Subcarrier Allocation for Full-Duplex
  Multicarrier Non-Orthogonal Multiple Access Systems

abstract:
  In this paper, we investigate resource allocation algorithm design for
multicarrier non-orthogonal multiple access (MC-NOMA) systems employing a
full-duplex (FD) base station (BS) for serving multiple half-duplex (HD)
downlink (DL) and uplink (UL) users simultaneously. The proposed algorithm is
obtained from the solution of a non-convex optimization problem for the
maximization of the weighted sum system throughput. We apply monotonic
optimization to develop an optimal joint power and subcarrier allocation
policy. The optimal resource allocation policy serves as a system performance
benchmark due to its high computational complexity. Furthermore, a suboptimal
iterative scheme based on successive convex approximation is proposed to strike
a balance between computational complexity and optimality. Our simulation
results reveal that the proposed suboptimal algorithm achieves a
close-to-optimal performance. Besides, FD MC-NOMA systems employing the
proposed resource allocation algorithms provide a substantial system throughput
improvement compared to conventional HD multicarrier orthogonal multiple access
(MC-OMA) systems and other baseline schemes. Also, our results unveil that the
proposed FD MC-NOMA systems achieve a fairer resource allocation compared to
traditional HD MC-OMA systems.


title:
A Novel Model for Distributed Big Data Service Composition using
  Stratified Functional Graph Matching

abstract:
  A significant number of current industrial applications rely on web services.
A cornerstone task in these applications is discovering a suitable service that
meets the threshold of some user needs. Then, those services can be composed to
perform specific functionalities. We argue that the prevailing approach to
compose services based on the "all or nothing" paradigm is limiting and leads
to exceedingly high rejection of potentially suitable services. Furthermore,
contemporary models do not allow "mix and match" composition from atomic
services of different composite services when binary matching is not possible
or desired. In this paper, we propose a new model for service composition based
on "stratified graph summarization" and "service stitching". We discuss the
limitations of existing approaches with a motivating example, present our
approach to overcome these limitations, and outline a possible architecture for
service composition from atomic services. Our thesis is that, with the advent
of Big Data, our approach will reduce latency in service discovery, and will
improve efficiency and accuracy of matchmaking and composition of services.


title: Sparse additive Gaussian process with soft interactions

abstract:
  Additive nonparametric regression models provide an attractive tool for
variable selection in high dimensions when the relationship between the
response and predictors is complex. They offer greater flexibility compared to
parametric non-linear regression models and better interpretability and
scalability than the non-parametric regression models. However, achieving
sparsity simultaneously in the number of nonparametric components as well as in
the variables within each nonparametric component poses a stiff computational
challenge. In this article, we develop a novel Bayesian additive regression
model using a combination of hard and soft shrinkages to separately control the
number of additive components and the variables within each component. An
efficient algorithm is developed to select the importance variables and
estimate the interaction network. Excellent performance is obtained in
simulated and real data examples.


title: PINGU: A Vision for Neutrino and Particle Physics at the South Pole

abstract:
  The Precision IceCube Next Generation Upgrade (PINGU) is a proposed
low-energy in-fill extension to the IceCube Neutrino Observatory. With
detection technology modeled closely on the successful IceCube example, PINGU
will provide a 6Mton effective mass for neutrino detection with an energy
threshold of a few GeV. With an unprecedented sample of over 60,000 atmospheric
neutrinos per year in this energy range, PINGU will make highly competitive
measurements of neutrino oscillation parameters in an energy range over an
order of magnitude higher than long-baseline neutrino beam experiments. PINGU
will measure the mixing parameters $\theta_{\rm 23}$ and $\Delta m^2_{\rm 32}$,
including the octant of $\theta_{\rm 23}$ for a wide range of values, and
determine the neutrino mass ordering at $3\sigma$ median significance within 4
years of operation. PINGU's high precision measurement of the rate of
${\nu_\tau}$ appearance will provide essential tests of the unitarity of the
$3\times 3$ PMNS neutrino mixing matrix. PINGU will also improve the
sensitivity of searches for low mass dark matter in the Sun, use neutrino
tomography to directly probe the composition of the Earth's core, and improve
IceCube's sensitivity to neutrinos from Galactic supernovae. Reoptimization of
the PINGU design has permitted substantial reduction in both cost and
logistical requirements while delivering performance nearly identical to
configurations previously studied. This document summarizes the results of
detailed studies described in a more comprehensive document to be released
soon.


title:
Few-body collective excitations beyond Kohn's theorem in quantum Hall
  systems

abstract:
  A relative coordinate breathing mode in the quantum Hall system is predicted
to exist with different behavior under either Coulomb or dipole-dipole
interactions. While Kohn's theorem predicts that any relative coordinate
interaction will fail to alter the center of mass energy spectrum, it can
affect excitations in the relative coordinates. One such collective excitation,
which we call the hyperradial breathing mode, emerges naturally from a
few-body, hyperspherical representation of the problem and depends on the
inter-particle interactions, the ground state wave function, and the number of
particles participating in the excitation. Possible observations of this
excitation will be discussed in the context of both cold rotating atomic
simulations and conventional quantum Hall experiments.


title:
Quantum centrality testing on directed graphs via PT-symmetric quantum
  walks

abstract:
  Various quantum-walk based algorithms have been proposed to analyse and rank
the centrality of graph vertices. However, issues arise when working with
directed graphs --- the resulting non-Hermitian Hamiltonian leads to
non-unitary dynamics, and the total probability of the quantum walker is no
longer conserved. In this paper, we discuss a method for simulating directed
graphs using PT-symmetric quantum walks, allowing probability conserving
non-unitary evolution. This method is equivalent to mapping the directed graph
to an undirected, yet weighted, complete graph over the same vertex set, and
can be extended to cover interdependent networks of directed graphs. Previous
work has shown centrality measures based on the CTQW provide an
eigenvector-like quantum centrality; using the PT-symmetric framework, we
extend these centrality algorithms to directed graphs with a significantly
reduced Hilbert space compared to previous proposals. In certain cases, this
centrality measure provides an advantage over classical algorithms used in
network analysis, for example by breaking vertex rank degeneracy. Finally, we
perform a statistical analysis over ensembles of random graphs, and show strong
agreement with the classical PageRank measure on directed acyclic graphs.


title:
Network-Wide Distributed Carrier Frequency Offsets Estimation and
  Compensation

abstract:
  In this paper, we propose a fully distributed algorithm for frequency offsets
estimation in decentralized systems. With the proposed algorithm, each node
estimates its frequency offsets by local computations and limited exchange of
information with its direct neighbors. Such algorithm does not require any
centralized information processing or knowledge of global network topology. It
is shown analytically that the proposed algorithm always converges to the
optimal estimates regardless of network topology. Simulation results
demonstrate the fast convergence of the algorithm and show that estimation
mean-squared-error at each node touches the centralized Cram\'{e}r-Rao bound
within a few {iterations of message exchange}. Therefore, the proposed method
has low overhead and is scalable with network size.


title: Covariate Regularized Community Detection in Sparse Graphs

abstract:
  In this paper, we investigate community detection in networks in the presence
of node covariates. In many instances, covariates and networks individually
only give a partial view of the cluster structure. One needs to jointly infer
the full cluster structure by considering both. In statistics, an emerging body
of work has been focused on combining information from both the edges in the
network and the node covariates to infer community memberships. However, so far
the theoretical guarantees have been established in the dense regime, where the
network can lead to perfect clustering under a broad parameter regime, and
hence the role of covariates is often not clear. In this paper, we examine
sparse networks in conjunction with finite dimensional sub-gaussian mixtures as
covariates under moderate separation conditions. In this setting each
individual source can only cluster a non-vanishing fraction of nodes correctly.
We propose a simple optimization framework which provably improves clustering
accuracy when the two sources carry partial information about the cluster
memberships, and hence perform poorly on their own. Our optimization problem
can be solved using scalable convex optimization algorithms. Using a variety of
simulated and real data examples, we show that the proposed method outperforms
other existing methodology.


abstract:
  Ensemble of regression trees have become popular statistical tools for the
estimation of conditional mean given a set of predictors. However, quantile
regression trees and their ensembles have not yet garnered much attention
despite the increasing popularity of the linear quantile regression model. This
work proposes a Bayesian quantile additive regression trees model that shows
very good predictive performance illustrated using simulation studies and real
data applications. Further extension to tackle binary classification problems
is also considered.


title:
Construction of Cyclic and Constacyclic Codes for b-symbol Read Channels
  Meeting the Plotkin-like Bound

abstract:
  The symbol-pair codes over finite fields have been raised for symbol-pair
read channels and motivated by application of high-density data storage
technologies [1, 2]. Their generalization is the code for b-symbol read
channels (b > 2). Many MDS codes for b-symbol read channels have been
constructed which meet the Singleton-like bound ([3, 4, 10] for b = 2 and [11]
for b > 2). In this paper we show the Plotkin-like bound and present a
construction on irreducible cyclic codes and constacyclic codes meeting the
Plotkin-like bound.


title: Towards an "In-the-Wild" Emotion Dataset Using a Game-based Framework

abstract:
  In order to create an "in-the-wild" dataset of facial emotions with large
number of balanced samples, this paper proposes a game-based data collection
framework. The framework mainly include three components: a game engine, a game
interface, and a data collection and evaluation module. We use a deep learning
approach to build an emotion classifier as the game engine. Then a emotion web
game to allow gamers to enjoy the games, while the data collection module
obtains automatically-labelled emotion images. Using our game, we have
collected more than 15,000 images within a month of the test run and built an
emotion dataset "GaMo". To evaluate the dataset, we compared the performance of
two deep learning models trained on both GaMo and CIFE. The results of our
experiments show that because of being large and balanced, GaMo can be used to
build a more robust emotion detector than the emotion detector trained on CIFE,
which was used in the game engine to collect the face images.


title: Optimal free descriptions of many-body theories

abstract:
  Interacting bosons or fermions give rise to some of the most fascinating
phases of matter, including high-temperature superconductivity, the fractional
quantum Hall effect, quantum spin liquids and Mott insulators. While these
systems are promising for technological applications, they also present
conceptual challenges as they require approaches beyond mean-field and
perturbation theory. Here we develop a general framework for identifying the
free theory that is closest to a given interacting model in terms of their
ground state correlations. Moreover, we quantify the distance between them
using the entanglement spectrum. When this interaction distance is small, the
optimal free theory provides an effective description of the low energy physics
of the interacting model. Our construction of the optimal free model is
non-perturbative in nature, thus it offers a new theoretical framework for
investigating strongly correlated systems.


title: The smoothness of the stationary measure

abstract:
  We study the smoothness of the stationary measure with respect to smooth
perturbations of the iterated function scheme and the weight functions that
define it. Our main theorems relate the smoothness of the perturbation of: the
iterated function scheme and the weight functions; to the smoothness of the
perturbation of the stationary measure. The results depend on the smoothness
of: the iterated function scheme and the weights functions; and the space on
which the stationary measure acts as a linear operator. As a consequence we
also obtain the smoothness of the Hausdorff dimension of the limit set and of
the Hausdorff dimension of the stationary measure.


title:
Perturbation-Assisted PAPR Reduction for Large-Scale MIMO-OFDM Systems
  via ADMM

abstract:
  We consider the problem of peak-to-average power ratio (PAPR) reduction for
orthogonal frequency-division multiplexing (OFDM) based large-scale
multiple-input multipleoutput (MIMO) systems. A novel perturbation-assisted
scheme is developed to reduce the PAPRs of the transmitted signals by
exploiting the redundant degrees-of-freedom (DoFs) inherent in the large-scale
antenna array. Specifically, we introduce artificial perturbation signals to
the frequency-domain precoded signals, with the aim of reducing the PAPRs of
their time-domain counterpart signals. Meanwhile, the additive perturbation
signal associated with each tone is constrained to lie in the null-space of its
associated channel matrix, such that it does not cause any multi-user inference
or out-of-band radiations. Such a problem is formulated as a convex
optimization problem, and an efficient algorithm is developed by resorting to
the variable splitting and alterative direction method of multipliers (ADMM)
techniques. Simulation results show that the proposed method has a fast
convergence rate and achieves substantial PAPR reduction within only tens of
iterations. In addition, unlike other precoding-based PAPR reduction methods,
our proposed method which introduces perturbation signals to the precoded
signals is independent of the precoding stage and thus could be more suitable
for practical systems.


title:
Extending Weakly-Sticky Datalog+/-: Query-Answering Tractability and
  Optimizations

abstract:
  Weakly-sticky (WS) Datalog+/- is an expressive member of the family of
Datalog+/- programs that is based on the syntactic notions of stickiness and
weak-acyclicity. Query answering over the WS programs has been investigated,
but there is still much work to do on the design and implementation of
practical query answering (QA) algorithms and their optimizations. Here, we
study sticky and WS programs from the point of view of the behavior of the
chase procedure, extending the stickiness property of the chase to that of
generalized stickiness of the chase (gsch-property). With this property we
specify the semantic class of GSCh programs, which includes sticky and WS
programs, and other syntactic subclasses that we identify. In particular, we
introduce joint-weakly-sticky (JWS) programs, that include WS programs. We also
propose a bottom-up QA algorithm for a range of subclasses of GSCh. The
algorithm runs in polynomial time (in data) for JWS programs. Unlike the WS
class, JWS is closed under a general magic-sets rewriting procedure for the
optimization of programs with existential rules. We apply the magic-sets
rewriting in combination with the proposed QA algorithm for the optimization of
QA over JWS programs.


title:
Resonance phenomena in a scalar delay differential equation with two
  state-dependent delays

abstract:
  We study a scalar DDE with two delayed feedback terms that depend linearly on
the state. The associated constant-delay DDE, obtained by freezing the state
dependence, is linear and without recurrent dynamics. With state dependent
delay terms, on the other hand, the DDE shows very complicated dynamics. To
investigate this, we perform a bifurcation analysis of the system and present
its bifurcation diagram in the plane of the two feedback strengths. It is
organized by Hopf-Hopf bifurcation points that give rise to curves of torus
bifurcation and associated two-frequency dynamics in the form of invariant tori
and resonance tongues. We numerically determine the type of the Hopf-Hopf
bifurcation points by computing the normal form on the center manifold; this
requires the expansion of the functional defining the state-dependent DDE in a
power series whose terms up to order three only contain constant delays. We
implemented this expansion and the computation of the normal form coefficients
in Matlab using symbolic differentiation. Numerical continuation of the torus
bifurcation curves confirms the correctness of our normal form calculations.
Moreover, it enables us to compute the curves of torus bifurcations more
globally, and to find associated curves of saddle-node bifurcations of periodic
orbits that bound the resonance tongues. The tori themselves are computed and
visualized in a three-dimensional projection, as well as the planar trace of a
suitable Poincar\'e section. In particular, we compute periodic orbits on
locked tori and their associated unstable manifolds. This allows us to study
transitions through resonance tongues and the breakup of a 1:4 locked torus.
The work presented here demonstrates that state dependence alone is capable of
generating a wealth of dynamical phenomena.


title:
Realizations of globally exceptional $\mathbb{Z}_2 \times \mathbb{Z}_2$-
  symmetric spaces

abstract:
  A classification is given of the exceptional $\mathbb{Z}_2 \times
\mathbb{Z}_2$-symmetric spaces $G/K$ by A.Kollross, where $G$ is an exceptional
compact Lie group or $S\!pin(8)$, and moreover the structure of $K$ is
determined as Lie algebra. In the present article, we give a pair of commuting
involutive automorphisms (involutions) $\tilde{\sigma}, \tilde{\tau}$ of $G$
concretely and determine the structure of group $G^{\sigma} \cap G^{\tau}$
corresponding to Lie algebra $\mathfrak{g}^\sigma \cap \mathfrak{g}^\tau$,
where $G$ is an exceptional compact Lie group. Thereby, we realize exceptional
$\mathbb{Z}_2 \times \mathbb{Z}_2$-symmetric spaces, globally.


title: Theory of finite periodic systems: The eigenfunctions symmetries

abstract:
  Using the analytical expressions for the genuine eigenfunctions
$\varphi_{\mu\nu}(z)$ and eigenvalues $E_{\mu,\nu}$, of open, bounded and
quasi-bounded finite periodic systems, we derive the eigenfunctions
space-inversion symmetry relations. The superlattice eigenfunctions symmetries,
closely related with the symmetries and zeros of the Chebyshev polynomials of
the second kind $U_n$, are fully written in terms of the number of unit cells
$n$, the subband index $\mu$ and the intra-subband index $\nu$.


title:
Improved optical transitions theory for superlattices and periodic
  systems; new selection rules

abstract:
  Using the superlattice (SL) eigenvalues $E_{\mu ,\nu }^{c,v}$ and
eigenfunctions $\varphi_{\mu\nu}^{c,v}(z) $, obtained within the theory of
finite periodic systems, where $\mu$ indicates the subbands and $\nu$ the
intra-subband levels, we calculate optical transitions in SLs and periodic
systems. Based on the eigenfunction parity symmetries, studied in the previous
paper, new symmetry selection rules (SSR) are derived and photoluminescence and
infrared spectra for different types of SLs are calculated. The narrow peaks
clustered in groups that couldn't be explained before in Nakamura's et al. for
blue emitting devices, are now fully understood. Among the various properties
and differences that we discuss in the paper, we notice that many transitions
that were experimentally observed but theoretically forbidden, are now
perfectly possible. Since the number of matrix-elements allowed by the SSR is
generally too large, we devote the second part of this paper to show that one
can obtain the same spectra when, besides the SSR, other leading order
selection rules closely related to intra-subband symmetries are introduced.
These rules reduce the number of matrix evaluations from $\sim n^2$$n_cn_v/2$
to $\sim n$$n_cn_v/2$, i.e., depending on the SL, from about 1000 to 100. We
comment also on a third rule, that picks up the contributions of the surface
and edge states, and show that it reduces further the number of transitions to
$N_s\leq n_cn_v$. With these rules, the main peaks are conserved and their
number practically matches with that of the actual spectrum. Excellent
agreements with experimental results are found.


title: Accelerated Evaluation of Automated Vehicles in Car-Following Maneuvers

abstract:
  The safety of Automated Vehicles (AVs) must be assured before their release
and deployment. The current approach to evaluation relies primarily on (i)
testing AVs on public roads or (ii) track testing with scenarios defined in a
test matrix. These two methods have completely opposing drawbacks: the former,
while offering realistic scenarios, takes too much time to execute; the latter,
though it can be completed in a short amount of time, has no clear correlation
to safety benefits in the real world. To avoid the aforementioned problems, we
propose Accelerated Evaluation, focusing on the car-following scenario. The
stochastic human-controlled vehicle (HV) motions are modeled based on 1.3
million miles of naturalistic driving data collected by the University of
Michigan Safety Pilot Model Deployment Program. The statistics of the HV
behaviors are then modified to generate more intense interactions between HVs
and AVs to accelerate the evaluation procedure. The Importance Sampling theory
was used to ensure that the safety benefits of AVs are accurately assessed
under accelerated tests. Crash, injury and conflict rates for a simulated AV
are simulated to demonstrate the proposed approach. Results show that test
duration is reduced by a factor of 300 to 100,000 compared with the
non-accelerated (naturalistic) evaluation. In other words, the proposed
techniques have great potential for accelerating the AV evaluation process.


title: On the time consistency of collective preferences

abstract:
  A dynamic model of collective consumption and saving decisions made by a
finite number of agents with constant but different discount rates is
developed. Collective utility is a weighted sum of individual utilities with
time-varying utility weights. Under standard separability assumptions, it is
shown that collective preferences may be nonstationary but still satisfy time
consistency. The assumption of time-varying weights is key to balance the need
of the group for a changing distribution of consumption among its members over
time with their tolerance for consumption fluctuations.


title:
On the Unique Crossing Conjecture of Diaconis and Perlman on
  Convolutions of Gamma Random Variables

abstract:
  Diaconis and Perlman (1990) conjecture that the distribution functions of two
weighted sums of iid gamma random variables cross exactly once if one weight
vector majorizes the other. We disprove this conjecture when the shape
parameter of the gamma variates is $\alpha <1$ and prove it when $\alpha\geq
1$.


title:
Classical and Quantum Szilard Engine under Generalized Uncertainty
  Principle Effect

abstract:
  We studied the Szilard engine under the effect of generalized uncertainty
principle (GUP). In the classical Szilard engine, the work done by the engine
is reduced by the GUP effect via a modified ideal gas law. In the quantum
Szilard engine, the correction comes from the shifted eigen energy due to the
nonlinear momentum dependence. We studied its effect on both bosonic and
fermionic molecules.


title: Charmonium dissociation in collision with phi meson in hadronic matter

abstract:
  The phi-charmonium dissociation reactions in hadronic matter are studied.
Unpolarised cross sections for 12 reactions are calculated in the Born
approximation, in the quark-interchange mechanism and with a
temperature-dependent quark potential. The potential leads to remarkable
temperature dependence of the cross sections. With the cross sections and the
phi distribution function we calculate the dissociation rates of the charmonia
in the interactions with the phi meson in hadronic matter. The dependence of
the rates on temperature and charmonium momentum is meaningful to the influence
of phi mesons on charmonium suppression.


title: Time optimal control in coupled spin systems: a second order analysis

abstract:
  In this paper, we study some control problems that derive from time optimal
control of coupled spin dynamics in NMR spectroscopy and quantum information
and computation. Time optimal control helps to minimize relaxation losses. The
ability to synthesize, local unitaries, much more rapidly than evolution of
couplings, gives a natural time scale separation in these problems. The
generators of evolution, $\g$, are decomposed into fast generators $\k$ (local
Hamiltonians) and slow generators $\p$ (couplings) as a Cartan decomposition
$\g = \p \oplus \k$. Using this decomposition, we exploit some convexity ideas
to completely characterize the reachable set and time optimal control for these
problems. In this paper, we carry out a second order analysis of time
optimality.


title: Remark on higher-derivative mechanics with l-conformal Galilei symmetry

abstract:
  Based on the results in [Nucl. Phys. B 866 (2013) 212], we consider a way to
construct a higher-derivative mechanical model which possesses the
$l$-conformal Galilei symmetry. The dynamical system describes generalized
Pais-Uhlenbeck oscillator in the presence of an effective external field.


title: Proceedings of the 4th International Workshop on Strategic Reasoning

abstract:
  This volume contains the proceedings of the Fourth International Workshop on
Strategic Reasoning (SR 2016), held in New York City (USA), July 10, 2016. The
workshop consisted of 2 keynote talks and 9 contributed presentations on themes
of logic, verification, games and equilibria.
  More information about the Strategic Workshop series is available at
http://www.strategicreasoning.net/


title: Visual Motion Onset Brain-computer Interface

abstract:
  The paper presents a study of two novel visual motion onset stimulus-based
brain-computer interfaces (vmoBCI). Two settings are compared with afferent and
efferent to a computer screen center motion patterns. Online vmoBCI experiments
are conducted in an oddball event-related potential (ERP) paradigm allowing for
"aha-responses" decoding in EEG brainwaves. A subsequent stepwise linear
discriminant analysis classification (swLDA) classification accuracy comparison
is discussed based on two inter-stimulus-interval (ISI) settings of 700 and 150
ms in two online vmoBCI applications with six and eight command settings. A
research hypothesis of classification accuracy non-significant differences with
various ISIs is confirmed based on the two settings of 700 ms and 150 ms, as
well as with various numbers of ERP response averaging scenarios. The efferent
in respect to display center visual motion patterns allowed for a faster
interfacing and thus they are recommended as more suitable for the
no-eye-movements requiring visual BCIs.


title:
Fast adiabatic quantum state transfer and entanglement generation
  between two atoms via dressed states

abstract:
  Recently, a new method, which can significantly speed up adiabatic quantum
state transfer by using dressed states, was proposed by Baksic \emph{et~al.}
[Phys. Rev. Lett. \textbf{116}, 230503 (2016)]. Assisted by quantum Zeno
dynamics, we develop this dressed-state method to achieve shortcuts to complete
and fractional stimulated Raman adiabatic passage for speeding up adiabatic
two-atom quantum state transfer and maximum entanglement generation,
respectively. By means of some numerical simulations, we determine the
parameters used in the scheme which can guarantee the feasibility and
efficiency both in theory and experiment. Besides, we give strict numerical
simulations to discuss the scheme's robustness, and the results show the scheme
is robust against the variations in the parameters, atomic spontaneous
emissions and the photon leakages from the cavity.


title: Robust Topological Terahertz Circuits using Semiconductors

abstract:
  Topological Insulator-based devices can transport electrons/photons at the
surfaces of materials without any back reflections, even in the presence of
obstacles. Topological properties have recently been studied using
non-reciprocal materials such as gyromagnetics or using bianisotropy. However,
these effects usually saturate at optical frequencies and limit our ability to
scale down devices. In order to implement topological devices that we introduce
in this paper for the terahertz range, we show that semiconductors can be
utilized via their cyclotron resonance in combination with small magnetic
fields. We propose novel terahertz operating devices such as the topological
tunable power splitter and the topological circulator. This work opens new
perspectives in the design of terahertz integrated devices and circuits with
high functionality.


title:
Violation of cosmic censorship in the gravitational collapse of a dust
  cloud in five dimension

abstract:
  We analyze the null geodesic equations in five dimensional spherically
symmetric spacetime with collapsing inhomogeneous dust cloud. By using a new
method, we prove the existence and non-existence of solutions to null geodesic
equation emanating from central singularity for smooth initial distribution of
dust. Moreover, we also show that the null geodesics can extend to null
infinity in a certain case, which imply the violation of cosmic censorship
conjecture.


title:
At Every Corner: Determining Corner Points of Two-User Gaussian
  Interference Channels

abstract:
  The corner points of the capacity region of the two-user Gaussian
interference channel under strong or weak interference are determined using the
notions of almost Gaussian random vectors, almost lossless addition of random
vectors, and almost linearly dependent random vectors. In particular, the
"missing" corner point problem is solved in a manner that differs from previous
works in that it avoids the use of integration over a continuum of SNR values
or of Monge-Kantorovitch transportation problems.


title: Double Soft Theorem for Perturbative Gravity

abstract:
  Following up on the recent work of Cachazo, He and Yuan
\cite{arXiv:1503.04816 [hep-th]}, we derive the double soft graviton theorem in
perturbative gravity. We show that the double soft theorem derived using CHY
formula precisely matches with the perturbative computation involving Feynman
diagrams. In particular, we find how certain delicate limits of Feynman
diagrams play an important role in obtaining this equivalence.


title:
Algebraic formulas for the coefficients of mock theta functions and Weyl
  vectors of Borcherds products

abstract:
  We present some applications of the Kudla-Millson and the Millson theta lift.
The two lifts map weakly holomorphic modular functions to vector valued
harmonic Maass forms of weight $3/2$ and $1/2$, respectively. We give finite
algebraic formulas for the coefficients of Ramanujan's mock theta functions
$f(q)$ and $\omega(q)$ in terms of traces of CM-values of a weakly holomorphic
modular function. Further, we construct vector valued harmonic Maass forms
whose shadows are unary theta functions, and whose holomorphic parts have
rational coefficients. This yields a rationality result for the coefficients of
mock theta functions, i.e., harmonic Maass forms whose shadows lie in the space
of unary theta functions. Moreover, the harmonic Maass forms we construct can
be used to evaluate the Petersson inner products of unary theta functions with
harmonic Maass forms, giving formulas and rationality results for the Weyl
vectors of Borcherds products.


title: Higher associativity of Moore spectra

abstract:
  The Moore spectrum $\mathrm{M}_p(i)$ is the cofiber of the $p^{i}$ map on the
sphere spectrum. For a fixed $p$ and $n$, we find a lower bound on $i$ for
which $\mathrm{M}_p(i)$ is guaranteed to be $n$-fold associative. This bound
depends on the stable homotopy groups of spheres.


title: Higgs pair productions in the CP-violating two-Higgs-doublet model

abstract:
  In this work, we study the SM-like Higgs pair productions in the framework of
the general CP-violating two-Higgs-doublet model. Several constraints are
imposed to the model sequentially, including the SM-like Higgs boson signal
fits, the precise measurements of the electric dipole moments, the perturbative
unitarity and stability bounds to the Higgs potential, and the most recent LHC
searches for the heavy Higgs bosons. We show how are the CP-violating mixing
angles related to the Higgs cubic self couplings in this setup. Afterwards, we
estimate the cross sections of the future LHC/SppC searches for the Higgs pair
productions, as well as other possible decay modes for the heavy Higgs bosons.


title:
Next-to-leading order QCD corrections to Higgs boson decay to quarkonium
  plus a photon

abstract:
  In this paper, we investigate the decay of Higgs boson to $J/\psi(\Upsilon)$
plus a photon based on NRQCD factorization. For the direct process, we
calculate the decay width up to QCD NLO. We find that the decay width for
process $H \to J/\psi(\Upsilon)+ \gamma$ direct production at the LO is
significantly reduced by the NLO QCD corrections. For the indirect process, we
calculate the $H \to \gamma^\ast\gamma$ with virtual $\gamma$ substantially
decaying to $J/\psi(\Upsilon)$, including all the SM Feynman diagrams. The
decay width of indirect production is much larger than the direct decay width.
Since it is very clean in experiment, the $H \to J/\psi(\Upsilon)+ \gamma$
decay could be observable at a 14 TeV LHC and it also offers a new way to probe
the Yukawa coupling and New Physics at the LHC.


title: Dealing with Class Imbalance using Thresholding

abstract:
  We propose thresholding as an approach to deal with class imbalance. We
define the concept of thresholding as a process of determining a decision
boundary in the presence of a tunable parameter. The threshold is the maximum
value of this tunable parameter where the conditions of a certain decision are
satisfied. We show that thresholding is applicable not only for linear
classifiers but also for non-linear classifiers. We show that this is the
implicit assumption for many approaches to deal with class imbalance in linear
classifiers. We then extend this paradigm beyond linear classification and show
how non-linear classification can be dealt with under this umbrella framework
of thresholding. The proposed method can be used for outlier detection in many
real-life scenarios like in manufacturing. In advanced manufacturing units,
where the manufacturing process has matured over time, the number of instances
(or parts) of the product that need to be rejected (based on a strict regime of
quality tests) becomes relatively rare and are defined as outliers. How to
detect these rare parts or outliers beforehand? How to detect combination of
conditions leading to these outliers? These are the questions motivating our
research. This paper focuses on prediction of outliers and conditions leading
to outliers using classification. We address the problem of outlier detection
using classification. The classes are good parts (those passing the quality
tests) and bad parts (those failing the quality tests and can be considered as
outliers). The rarity of outliers transforms this problem into a
class-imbalanced classification problem.


title: Spontaneous spherical symmetry breaking in atomic confinement

abstract:
  The effect of spontaneous breaking of initial SO(3) symmetry is shown to be
possible for an H-like atom in the ground state, when it is confined in a
spherical box under general boundary conditions of "not going out" through the
box surface (i.e. third kind or Robin's ones), for a wide range of physically
reasonable values of system parameters. The reason is that such boundary
conditions could yield a large magnitude of electronic wavefunction in some
sector of the box boundary, what in turn promotes atomic displacement from the
box center towards this part of the boundary, and so the underlying SO(3)
symmetry spontaneously breaks. The emerging Goldstone modes, coinciding with
rotations around the box center, restore the symmetry by spreading the atom
over a spherical shell localized at some distances from the box center. Atomic
confinement inside the cavity proceeds dynamically -- due to the boundary
condition the deformation of electronic wavefunction near the boundary works as
a spring, that returns the atomic nuclei back into the box volume.


title: The radio spectral energy distribution of infrared-faint radio sources

abstract:
  Infrared-faint radio sources (IFRS) are a class of radio-loud (RL) active
galactic nuclei (AGN) at high redshifts (z > 1.7) that are characterised by
their relative infrared faintness, resulting in enormous radio-to-infrared flux
density ratios of up to several thousand. We aim to test the hypothesis that
IFRS are young AGN, particularly GHz peaked-spectrum (GPS) and compact
steep-spectrum (CSS) sources that have a low frequency turnover. We use the
rich radio data set available for the Australia Telescope Large Area Survey
fields, covering the frequency range between 150 MHz and 34 GHz with up to 19
wavebands from different telescopes, and build radio spectral energy
distributions (SEDs) for 34 IFRS. We then study the radio properties of this
class of object with respect to turnover, spectral index, and behaviour towards
higher frequencies. We also present the highest-frequency radio observations of
an IFRS, observed with the Plateau de Bure Interferometer at 105 GHz, and model
the multi-wavelength and radio-far-infrared SED of this source. We find IFRS
usually follow single power laws down to observed frequencies of around 150
MHz. Mostly, the radio SEDs are steep, but we also find ultra-steep SEDs. In
particular, IFRS show statistically significantly steeper radio SEDs than the
broader RL AGN population. Our analysis reveals that the fractions of GPS and
CSS sources in the population of IFRS are consistent with the fractions in the
broader RL AGN population. We find that at least 18% of IFRS contain young AGN,
although the fraction might be significantly higher as suggested by the steep
SEDs and the compact morphology of IFRS. The detailed multi-wavelength SED
modelling of one IFRS shows that it is different from ordinary AGN, although it
is consistent with a composite starburst-AGN model with a star formation rate
of 170 solar masses per year.


title:
Exotic multi-gap structure in UPt$_3$ unveiled by the first-priniciples
  analysis

abstract:
  A heavy-fermion superconductor UPt$_3$ is a unique spin-triplet
superconductor with multiple superconducting phases. Here we provide the first
report on the first-principles analysis of the microscopic superconducting gap
structure. We find that the promising gap structure is an unprecedented
$E_{2u}$ state, which is completely different from the previous
phenomenological $E_{2u}$ models. Our obtained $E_{2u}$ state has in-plane
twofold vertical line nodes on small Fermi surfaces and point nodes with linear
dispersion on a large Fermi surface. These peculiar features cannot be
explained in the conventional spin $1/2$ representation, but is described by
the group-theoretical representation of the Cooper pairs in the total angular
momentum $j=5/2$ space. Our findings shed new light on the long-standing
problems in the superconductivity of UPt$_3$


title:
Thermal conductivity reduction by 60{\deg} shuffle-set dislocation
  arrays embedded in silicon nano-films

abstract:
  Based on the Debye-Callaway and the Klemens model, as well as molecular
dynamics, the paper proposes mechanism of thermal conductivity reduction by
embedding dense 60{\deg} shuffle-set dislocation arrays into silicon
nano-films. Thermal conductivity reduction to 2% of that of bulk silicon has
been obtained. The reduction is found mainly due to longitudinal phonon
scattering at the dislocation cores, where the scattering rate is stronger than
that presented by Klemens. Within an effective diameter of about 9 nm around
their cores, the dislocations locally scatter phonons, resulting in a
dramatical density-dependent reduction of thermal conductivity for a
dislocation density larger than 10^14 m^-2.


title:
Prediction of above $20$ K superconductivity of blue phosphorus bilayer
  with metal intercalations

abstract:
  First-principles calculations predicted monolayer blue phosphorus to be an
alternative two-dimensional allotrope of phosphorus, like the recently
discovered monolayer black phosphorus. Due to its unique crystalline and
electronic structure, blue phosphorus may be a promising candidate as a
BCS-superconductor after proper intercalation. In this study, using
first-principles calculations, the favorable intercalation sites for some
alkali metals and alkaline earths have been identified for Blue-P bilayer and
the stacking configuration of bilayer is changed. Then the blue phosphorus
bilayer transforms from a semiconductor to a metal due to the charge transfer
from metal to phosphorus. Own to the strong electron-phonon coupling, isotropic
superconducting state is induced and the calculated transition temperatures are
$20.4$, $20.1$, and $14.4$K for Li-, Na-, and Mg-intercaltion, respectively,
which is superior to other predicted or experimentally observed two-dimensional
BCS-superconductors.


title:
Second-harmonic assisted four-wave mixing in chip-based microresonator
  frequency comb generation

abstract:
  Simultaneous Kerr comb formation and second-harmonic generation with on-chip
microresonators can greatly facilitate comb self-referencing for optical clocks
and frequency metrology. Moreover, the presence of both second- and third-order
nonlinearities results in complex cavity dynamics that is of high scientific
interest but is still far from well understood. Here, we demonstrate that the
interaction between the fundamental and the second-harmonic waves can provide
an entirely new way of phase-matching for four-wave mixing in optical
microresonators, enabling the generation of optical frequency combs in the
normal dispersion regime, under conditions where comb creation is ordinarily
prohibited. We derive new coupled time-domain mean-field equations and obtain
simulation results showing good qualitative agreement with our experimental
observations. Our findings provide a novel way of overcoming the dispersion
limit for simultaneous Kerr comb formation and second-harmonic generation,
which might prove especially important in the near-visible to visible range
where several atomic transitions commonly used for stabilization of optical
clocks are located and where the large normal material dispersion is likely to
dominate.


title: Quantization Phenomena of critical Hamiltonians in 2D systems

abstract:
  This review work addresses the recent advances in solving more comprehensive
Hamiltonians. The generalized tight-binding model is developed to investigate
the feature-rich quantization phenomena in emergent 2D materials. The
mutli-orbital bondings, the spin-orbital interactions, the various geometric
structures, and the external fields are taken into consideration
simultaneously. Specifically, the IV-group layered systems, black phosphorus
and MoS$_{2}$ exhibit the unique magnetic quantization. This is clearly
indicated in three kinds of Landau levels (LLs), the orbital-, spin- and
valley-dependent LL groups, the abnormal LL energy spectra, and the splitting,
crossing and anticrossing behaviors. A detailed comparison with the
effective-mass model is made. Some theoretical predictions have been confirmed
by the experimental measurements.


title: Graded Hecke algebras for disconnected reductive groups

abstract:
  We introduce graded Hecke algebras H based on a (possibly disconnected)
complex reductive group G and a cuspidal local system L on a unipotent orbit of
a Levi subgroup M of G. These generalize the graded Hecke algebras defined and
investigated by Lusztig for connected G.
  We develop the representation theory of the algebras H. obtaining complete
and canonical parametrizations of the irreducible, the irreducible tempered and
the discrete series representations. All the modules are constructed in terms
of perverse sheaves and equivariant homology, relying on work of Lusztig. The
parameters come directly from the data (G,M,L) and they are closely related to
Langlands parameters.
  Our main motivation for considering these graded Hecke algebras is that the
space of irreducible H-representations is canonically in bijection with a
certain set of "logarithms" of enhanced L-parameters. Therefore we expect these
algebras to play a role in the local Langlands program. We will make their
relation with the local Langlands correspondence, which goes via affine Hecke
algebras, precise in a sequel to this paper.


title:
Privacy Leakage through Innocent Content Sharing in Online Social
  Networks

abstract:
  The increased popularity and ubiquitous availability of online social
networks and globalised Internet access have affected the way in which people
share content. The information that users willingly disclose on these platforms
can be used for various purposes, from building consumer models for
advertising, to inferring personal, potentially invasive, information. In this
work, we use Twitter, Instagram and Foursquare data to convey the idea that the
content shared by users, especially when aggregated across platforms, can
potentially disclose more information than was originally intended. We perform
two case studies: First, we perform user de-anonymization by mimicking the
scenario of finding the identity of a user making anonymous posts within a
group of users. Empirical evaluation on a sample of real-world social network
profiles suggests that cross-platform aggregation introduces significant
performance gains in user identification. In the second task, we show that it
is possible to infer physical location visits of a user on the basis of shared
Twitter and Instagram content. We present an informativeness scoring function
which estimates the relevance and novelty of a shared piece of information with
respect to an inference task. This measure is validated using an active
learning framework which chooses the most informative content at each given
point in time. Based on a large-scale data sample, we show that by doing this,
we can attain an improved inference performance. In some cases this performance
exceeds even the use of the user's full timeline.


title:
Learning to Sketch Human Facial Portraits using Personal Styles by
  Case-Based Reasoning

abstract:
  This paper employs case-based reasoning (CBR) to capture the personal styles
of individual artists and generate the human facial portraits from photos
accordingly. For each human artist to be mimicked, a series of cases are
firstly built-up from her/his exemplars of source facial photo and hand-drawn
sketch, and then its stylization for facial photo is transformed as a
style-transferring process of iterative refinement by looking-for and applying
best-fit cases in a sense of style optimization. Two models, fitness evaluation
model and parameter estimation model, are learned for case retrieval and
adaptation respectively from these cases. The fitness evaluation model is to
decide which case is best-fitted to the sketching of current interest, and the
parameter estimation model is to automate case adaptation. The resultant sketch
is synthesized progressively with an iterative loop of retrieval and adaptation
of candidate cases until the desired aesthetic style is achieved. To explore
the effectiveness and advantages of the novel approach, we experimentally
compare the sketch portraits generated by the proposed method with that of a
state-of-the-art example-based facial sketch generation algorithm as well as a
couple commercial software packages. The comparisons reveal that our CBR based
synthesis method for facial portraits is superior both in capturing and
reproducing artists' personal illustration styles to the peer methods.


title:
Classification of multipole superconductivity in multi-orbital systems
  and its implications

abstract:
  Motivated by a growing interest in multi-orbital superconductors with
spin-orbit interactions, we perform the group-theoretical classification of
various unconventional superconductivity emerging in symmorphic $\rm O$, $\rm
D_4$, and $\rm D_6$ space groups. The generalized Cooper pairs, which we here
call "multipole" superconductivity, possess spin-orbital coupled (multipole)
degrees of freedom, instead of the conventional spin singlet/triplet in
single-orbital systems. From the classification, we obtain the following key
consequences, which have been overlooked in the long history of research in
this field: (1) A superconducting gap function with
$\varGamma_9\otimes\varGamma_9$ in $\rm D_6$ possesses nontrivial momentum
dependence, different from the usual spin 1/2 classification. (2)
Unconventional gap structure can be realized in the BCS approximation of purely
local (on-site) interactions irrespective of attractive/repulsive. It implies
the emergence of an electron-phonon (e-ph) driven unconventional
superconductivity. (3) Reflecting symmetry of orbital basis functions, there
appear not symmetry-protected but inevitable line nodes/gap minima, and thus,
anisotropic $s$-wave superconductivity can be naturally explained without any
competitive fluctuations.


title: The BioDynaMo Project

abstract:
  Computer simulations have become a very powerful tool for scientific
research. Given the vast complexity that comes with many open scientific
questions, a purely analytical or experimental approach is often not viable.
For example, biological systems (such as the human brain) comprise an extremely
complex organization and heterogeneous interactions across different spatial
and temporal scales. In order to facilitate research on such problems, the
BioDynaMo project (\url{https://biodynamo.web.cern.ch/}) aims at a general
platform for computer simulations for biological research. Since the scientific
investigations require extensive computer resources, this platform should be
executable on hybrid cloud computing systems, allowing for the efficient use of
state-of-the-art computing technology. This paper describes challenges during
the early stages of the software development process. In particular, we
describe issues regarding the implementation and the highly interdisciplinary
as well as international nature of the collaboration. Moreover, we explain the
methodologies, the approach, and the lessons learnt by the team during these
first stages.


title: Branching fractions of $B_{(c)}$ decays involving $J/\psi$ and $X(3872)$

abstract:
  We study two-body $B_{(c)}\to M_c(\pi,K)$ and semileptonic $B_{c}\to
M_c\ell^-\bar \nu_\ell$ decays with $M_c=(J/\psi,X_c^0)$, where $X_c^0\equiv
X^0(3872)$ is regarded as the tetraquark state of $c\bar cu\bar u(d\bar d)$.
With the decay constant $f_{X_c^0}=(234\pm 52)$~MeV determined from the data,
we predict that ${\cal B}(B^-\to X_c^0\pi^-)=(11.5\pm 5.7)\times 10^{-6}$,
${\cal B}(\bar B^0\to X_c^0\bar K^0)=(2.1\pm 1.0)\times 10^{-4}$, and ${\cal
B}(\bar B^0_s\to X_c^0\bar K^0)=(11.4\pm 5.6)\times 10^{-6}$. With the form
factors in QCD models, we calculate that ${\cal B}(B_c^-\to X_c^0\pi^-,X_c^0
K^-)=(6.0\pm 2.6)\times 10^{-5}$ and $(4.7\pm 2.0)\times 10^{-6}$, and ${\cal
B}(B_c^-\to J/\psi \mu^-\bar \nu_\mu, X_c^0 \mu^-\bar \nu_\mu
)=(2.3\pm0.6)\times 10^{-2}$ and $(1.35\pm 0.18)\times 10^{-3}$, respectively,
and extract the ratio of the fragmentation fractions to be $f_c/f_u=(6.4\pm
1.9)\times 10^{-3}$.


title:
Quadratic descent of totally decomposable orthogonal involutions in
  characteristic two

abstract:
  We investigate the quadratic descent of totally decomposable algebras with
involution of orthogonal type in characteristic two. Both separable and
inseparable extensions are included.


title:
Intra-layer Nonuniform Quantization for Deep Convolutional Neural
  Network

abstract:
  Deep convolutional neural network (DCNN) has achieved remarkable performance
on object detection and speech recognition in recent years. However, the
excellent performance of a DCNN incurs high computational complexity and large
memory requirement. In this paper, an equal distance nonuniform quantization
(ENQ) scheme and a K-means clustering nonuniform quantization (KNQ) scheme are
proposed to reduce the required memory storage when low complexity hardware or
software implementations are considered. For the VGG-16 and the AlexNet, the
proposed nonuniform quantization schemes reduce the number of required memory
storage by approximately 50\% while achieving almost the same or even better
classification accuracy compared to the state-of-the-art quantization method.
Compared to the ENQ scheme, the proposed KNQ scheme provides a better tradeoff
when higher accuracy is required.


title:
Effect of isothermal holding temperature on the precipitation hardening
  in Vanadium-microalloyed steels with varying carbon and nitrogen levels

abstract:
  Combined effect of Carbon and Nitrogen levels and isothermal holding
temperature on the microstructure, precipitation and the tensile properties of
Vanadium microalloyed steels with 0.05 weight percent Vanadium were studied.
Two different Vanadium steels, one having higher Carbon and lower Nitrogen
content, HCLN steel, and the other having lower Carbon and higher Nitrogen
content, LCHN steel, were prepared and subjected to isothermal holding
treatment over a temperature range of 500 to 750 degree Celsius, after
hot-deformation. Maximum precipitation strengthening from fine Vanadium
carbonitride precipitates has been found at intermediate isothermal holding
temperatures i.e. 600 to 650 degree Celsius in both the steels. In spite of the
significantly smaller fraction of pearlite and bainite, coarser average ferrite
grain size and lower interaction of precipitation and dislocation in the
ferrite matrix, the yield strength of LCHN steel was close to HCLN steel. This
can be attributed to the higher precipitation strengthening ranging from 20 to
50 MPa resulted from the finer Vanadium precipitates in LCHN steel than that of
HCLN steel.


title:
Eutectic colony formation in systems with interfacial energy anisotropy:
  A phase field study

abstract:
  Instability of a binary eutectic solidification front to morphological
perturbations due to rejection of a ternary impurity leads to the formation of
eutectic colonies. Whereas, the instability dynamics and the resultant mi-
crostructural features are reasonably well understood for isotropic systems,
several experimental observations point to the existence of colonies in systems
with anisotropic interfaces. In this study, we extend the un- derstanding of
eutectic colonies to anisotropic systems, where only certain orientations of
the solid-liquid or solid-solid interfaces are thermodynamically stable.
Through phase field simulations in 2D and 3D, we have systematically probed the
colony formation dynamics and the resulting microstructures, as functions of
the pulling velocity and the relative orientation of the equilibrium interfaces
with that of the imposed tempera- ture gradient. We find that in 2D, stabler
finger spacings are selected with an increase in the magnitude of anisotropy
introduced, either in the solid-liquid or in the solid-solid interface. The
fingers have a well-defined orientation for the case of anisotropy in the
solid-liquid interface, with no fixed orientations for the lamellae
constituting the colony. For the case where anisotropy exists in the
solid-solid interface, the lamellae tend to orient themselves along the
direction of the imposed temperature gradient, with tilted solid-liquid
interfaces from the horizontal. The 3D simulations reveal existence of eutectic
spirals which might become tilted under certain orientations of the equilibrium
interfaces. Our simulations are able to explain several key features observed
in our experimantal studies of solidification in Ni-Al-Zr alloy.


title:
Well-posedness, Global existence and decay estimates for the heat
  equation with general power-exponential nonlinearities

abstract:
  In this paper we consider the problem: $\partial_{t} u- \Delta u=f(u),\;
u(0)=u_0\in \exp L^p(\R^N),$ where $p>1$ and $f : \R\to\R$ having an
exponential growth at infinity with $f(0)=0.$ We prove local well-posedness in
$\exp L^p_0(\R^N)$ for $f(u)\sim \mbox{e}^{|u|^q},\;0<q\leq p,\; |u|\to
\infty.$ However, if for some $\lambda>0,$ $\displaystyle\liminf_{s\to
\infty}\left(f(s)\,{\rm{e}}^{-\lambda s^p}\right)>0,$ then non-existence occurs
in $\exp L^p(\R^N).$ Under smallness condition on the initial data and for
exponential nonlinearity $f$ such that $|f(u)|\sim |u|^{m}$ as $u\to 0,$
${N(m-1)\over 2}\geq p$, we show that the solution is global. In particular,
$p-1>0$ sufficiently small is allowed. Moreover, we obtain decay estimates in
Lebesgue spaces for large time which depend on $m$.


title:
Monte-Carlo approach to calculate the ionization of warm dense matter
  within particle-in-cell simulations

abstract:
  A physical model based on a Monte-Carlo approach is proposed to calculate the
ionization dynam- ics of warm dense matters (WDM) within particle-in-cell
simulations, and where the impact (col- lision) ionization (CI), electron-ion
recombination (RE) and ionization potential depression (IPD) by surrounding
plasmas are taken into consideration self-consistently. When compared with
other models, which are applied in the literature for plasmas near thermal
equilibrium, the temporal re- laxation of ionization dynamics can also be
simulated by the proposed model. Besides, this model is general and can be
applied for both single elements and alloys with quite different composi-
tions. The proposed model is implemented into a particle-in-cell (PIC) code,
with (final) ionization equilibriums sustained by competitions between CI and
its inverse process (i.e., RE). Comparisons between the full model and model
without IPD or RE are performed. Our results indicate that for bulk aluminium
in the WDM regime, i) the averaged ionization degree increases by including
IPD; while ii) the averaged ionization degree is significantly over estimated
when the RE is neglected. A direct comparison from the PIC code is made with
the existing models for the dependence of averaged ionization degree on thermal
equilibrium temperatures, and shows good agreements with that generated from
Saha-Boltzmann model or/and FLYCHK code.


title: Fine-Grained Complexity Analysis of Two Classic TSP Variants

abstract:
  We analyze two classic variants of the Traveling Salesman Problem using the
toolkit of fine-grained complexity. Our first set of results is motivated by
the Bitonic TSP problem: given a set of $n$ points in the plane, compute a
shortest tour consisting of two monotone chains. It is a classic
dynamic-programming exercise to solve this problem in $O(n^2)$ time. While the
near-quadratic dependency of similar dynamic programs for Longest Common
Subsequence and Discrete Frechet Distance has recently been proven to be
essentially optimal under the Strong Exponential Time Hypothesis, we show that
bitonic tours can be found in subquadratic time. More precisely, we present an
algorithm that solves bitonic TSP in $O(n \log^2 n)$ time and its bottleneck
version in $O(n \log^3 n)$ time. Our second set of results concerns the popular
$k$-OPT heuristic for TSP in the graph setting. More precisely, we study the
$k$-OPT decision problem, which asks whether a given tour can be improved by a
$k$-OPT move that replaces $k$ edges in the tour by $k$ new edges. A simple
algorithm solves $k$-OPT in $O(n^k)$ time for fixed $k$. For 2-OPT, this is
easily seen to be optimal. For $k=3$ we prove that an algorithm with a runtime
of the form $\tilde{O}(n^{3-\epsilon})$ exists if and only if All-Pairs
Shortest Paths in weighted digraphs has such an algorithm. The results for
$k=2,3$ may suggest that the actual time complexity of $k$-OPT is
$\Theta(n^k)$. We show that this is not the case, by presenting an algorithm
that finds the best $k$-move in $O(n^{\lfloor 2k/3 \rfloor + 1})$ time for
fixed $k \geq 3$. This implies that 4-OPT can be solved in $O(n^3)$ time,
matching the best-known algorithm for 3-OPT. Finally, we show how to beat the
quadratic barrier for $k=2$ in two important settings, namely for points in the
plane and when we want to solve 2-OPT repeatedly.


title:
Monte-Carlo approach to calculate the proton stopping in warm dense
  matter within particle-in-cell simulations

abstract:
  A Monte-Carlo approach to proton stopping in warm dense matter is implemented
into an existing particle-in-cell code. The model is based on multiple
binary-collisions among electron-electron, electron-ion and ion-ion, taking
into account contributions from both free and bound electrons, and allows to
calculate particle stopping in much more natural manner. At low temperature
limit, when ``all'' electron are bounded at the nucleus, the stopping power
converges to the predictions of Bethe-Bloch theory, which shows good
consistency with data provided by the NIST. With the rising of temperatures,
more and more bound electron are ionized, thus giving rise to an increased
stopping power to cold matter, which is consistent with the report of a
recently experimental measurement [Phys. Rev. Lett. 114, 215002 (2015)]. When
temperature is further increased, with ionizations reaching the maximum,
lowered stopping power is observed, which is due to the suppression of
collision frequency between projected proton beam and hot plasmas in the
target.


title: Integral form of the COM-Poisson normalization constant

abstract:
  In this brief note an integral expression is presented for the COM-Poisson
renormalization constant $Z(\lambda, \nu)$ on the real axis.


title: Mega electrorheological phenomena in graphene nanogels

abstract:
  Unprecedentedly massive electrorheology has been reported for dilute graphene
nanoflakes based ER fluids that have been engineered as novel, readily
synthesizable polymeric gels. Polyethylene glycol based graphene gels have been
synthesized and very high ER response, 25,000 percent enhancement in viscosity
under influence of electric field, has been observed for low concentration
systems 2 wt. percent. The gels overcome several drawbacks innate to ER fluids.
The gels exhibit long term stability, high graphene packing ratio which ensures
very high ER response and the microstructure of the gels ensure that
fibrillation of the graphene nanoflakes under field is undisturbed by thermal
fluctuations, further leading to mega ER. The gels exhibit large yield stress
handling caliber with yield stress observed as high as 13 kPa at 2 wt. perc.
graphene. Detailed investigations on the effects of graphene concentration,
electric field strength, imposed shear resistance and transients of electric
field actuation on the ER response of the gels have been performed. The gels
show nearly negligible hysteresis with respect to electro viscous effects which
speak of the stability and responsiveness required in transient situations.
Indepth analyses with explanations have been provided for the observations and
effects, such as sheet over-crowding induced loss of structural integrity at
high concentrations and inter flake lubrication or slip induced augmented ER
response. The present gels show great promise as potential ER gels for variant
smart applications, such as damping and vibration control in active aircraft
and vehicle structures, micronanoscale electroactuation, in suspensions or
braking clutching in high performance specialized vehicular systems, etc.


title: Properties of particles in the ergosphere of black holes

abstract:
  A new feature of the rotating black holes is the existence in their
ergosphere of trajectories of particles with negative and zero energies. Here
we analyze general properties of such trajectories comparing them with usual
trajectories of particles with positive energy. A comparison with the situation
in rotating coordinate frame in Minkowski space-time is made. The possibility
of the unbounded growth of the energy of two colliding particles in the centre
of mass frame in the ergosphere is analysed.


title:
Selecting optimal parallel microchannel configurations for active hot
  spot mitigation of multicore microprocessors in real time

abstract:
  Design of effective micro cooling systems to address the challenges of ever
increasing heat flux from microdevices requires deep examination of real time
problems and has been tackled in depth. The most common and apparently
misleading assumption while designing micro cooling systems is that the heat
flux generated by the device is uniform, but the reality is far from this.
Detailed simulations have been performed by considering non uniform heat load
employing the configurations U, I, Z for parallel microchannel systems with
water and nanofluids as the coolants. An Intel Core i7 4770 3.40 GHz quad core
processor has been mimicked using heat load data retrieved from a real
microprocessor with non-uniform core activity. The study clearly demonstrates
that there is a non-uniform thermal load induced temperature maldistribution
along with the already existent flow maldistribution induced temperature
maldistribution. The suitable configuration(s) for maximum possible overall
heat removal for a hot zone while maximizing the uniformity of cooling have
been tabulated. An Eulerian Lagrangian model of the nanofluids show that such
smart coolants not only reduce the hot spot core temperature, but also the hot
spot core region and thermal slip mechanisms of Brownian diffusion and
thermophoresis are at the crux of this. The present work conclusively shows
that high flow maldistribution leads to high thermal maldistribution, as the
common prevalent notion, is no longer valid and existing maldistribution can be
effectively utilized to tackle specific hot spot location, making the present
study important to the field.


title: On the motion of free interface in ideal incompressible MHD

abstract:
  For the free boundary problem of the plasma-vacuum interface to
three-dimensional ideal incompressible magnetohydrodynamics (MHD), the a priori
estimates of smooth solutions are proved in Sobolev norms by adopting a
geometrical point of view and some quantities such as the second fundamental
form and the velocity of the free interface are estimated. In the vacuum
region, the magnetic fields are described by the div-curl system of pre-Maxwell
dynamics, while at the interface the total pressure is continuous and the
magnetic fields are tangent to the interface, but we do not need any
restrictions on the size of the magnetic fields on the free interface. We
introduce the "virtual particle" endowed with a virtual velocity field in
vacuum to reformulate the problem to a fixed boundary problem under the
Lagrangian coordinates. The $L^2$-norms of any order covariant derivatives of
the magnetic fields both in vacuum and on the boundaries are bounded in terms
of initial data and the second fundamental forms of the free interface and the
rigid wall. The estimates of the curl of the electric fields in vacuum are also
obtained, which are also indispensable in elliptic estimates.


title:
Averaging of equations of viscoelasticity with singularly oscillating
  external forces

abstract:
  Given $\rho\in[0,1]$, we consider for $\varepsilon\in(0,1]$ the nonautonomous
viscoelastic equation with a singularly oscillating external force $$
\partial_{tt} u-\kappa(0)\Delta u - \int_0^\infty \kappa'(s)\Delta u(t-s) d s
+f(u)=g_{0}(t)+\varepsilon ^{-\rho }g_{1}(t/\varepsilon ) $$ together with the
{\it averaged} equation $$ \partial_{tt} u-\kappa(0)\Delta u - \int_0^\infty
\kappa'(s)\Delta u(t-s) d s +f(u)=g_{0}(t). $$ Under suitable assumptions on
the nonlinearity and on the external force, the related solution processes
$S_\varepsilon(t,\tau)$ acting on the natural weak energy space ${\mathcal H}$
are shown to possess uniform attractors ${\mathcal A}^\varepsilon$. Within the
further assumption $\rho<1$, the family ${\mathcal A}^\varepsilon$ turns out to
be bounded in ${\mathcal H}$, uniformly with respect to $\varepsilon\in[0,1]$.
The convergence of the attractors ${\mathcal A}^\varepsilon$ to the attractor
${\mathcal A}^0$ of the averaged equation as $\varepsilon\to 0$ is also
established.


title: Towards Limited Scale-free Topology with Dynamic Peer Participation

abstract:
  Growth models have been proposed for constructing the scale-free overlay
topology to improve the performance of unstructured peer-to-peer (P2P)
networks. However, previous growth models are able to maintain the limited
scale-free topology when nodes only join but do not leave the network; the case
of nodes leaving the network while preserving a precise scaling parameter is
not included in the solution. Thus, the full dynamic of node participation,
inherent in P2P networks, is not considered in these models. In order to handle
both nodes joining and leaving the network, we propose a robust growth model
E-SRA, which is capable of producing the perfect limited scale-free overlay
topology with user-defined scaling parameter and hard cut-offs. Scalability of
our approach is ensured since no global information is required to add or
remove a node. E-SRA is also tolerant to individual node failure caused by
errors or attacks. Simulations have shown that E-SRA outperforms other growth
models by producing topologies with high adherence to the desired scale-free
property. Search algorithms, including flooding and normalized flooding,
achieve higher efficiency over the topologies produced by E-SRA.


title:
AccuracyTrader: Accuracy-aware Approximate Processing for Low Tail
  Latency and High Result Accuracy in Cloud Online Services

abstract:
  Modern latency-critical online services such as search engines often process
requests by consulting large input data spanning massive parallel components.
Hence the tail latency of these components determines the service latency. To
trade off result accuracy for tail latency reduction, existing techniques use
the components responding before a specified deadline to produce approximate
results. However, they may skip a large proportion of components when load gets
heavier, thus incurring large accuracy losses. This paper presents
AccuracyTrader that produces approximate results with small accuracy losses
while maintaining low tail latency. AccuracyTrader aggregates information of
input data on each component to create a small synopsis, thus enabling all
components producing initial results quickly using their synopses.
AccuracyTrader also uses synopses to identify the parts of input data most
related to arbitrary requests' result accuracy, thus first using these parts to
improve the produced results in order to minimize accuracy losses. We evaluated
AccuracyTrader using workloads in real services. The results show: (i)
AccuracyTrader reduces tail latency by over 40 times with accuracy losses of
less than 7% compared to existing exact processing techniques; (ii) when using
the same latency, AccuracyTrader reduces accuracy losses by over 13 times
comparing to existing approximate processing techniques.


title: Approximate Bayesian Computation for Lorenz Curves from Grouped Data

abstract:
  This paper proposes a new Bayesian approach to estimate the Gini coefficient
from the Lorenz curve based on grouped data. The proposed approach assumes a
hypothetical income distribution and estimates the parameter by directly
working on the likelihood function implied by the Lorenz curve of the income
distribution from the grouped data. It inherits the advantages of two existing
approaches through which the Gini coefficient can be estimated more accurately
and a straightforward interpretation about the underlying income distribution
is provided. Since the likelihood function is implicitly defined, the
approximate Bayesian computational approach based on the sequential Monte Carlo
method is adopted. The usefulness of the proposed approach is illustrated
through the simulation study and the Japanese income data.


title: From Quantum to Classical in the Sky

abstract:
  Inflation has by-far set itself as one of the prime ideas in the current
cosmological models that seemingly has an answer for every observed phenomenon
in cosmology. More importantly, it serves as a bridge between the early quantum
fluctuations and the present-day classical structures. Although the transition
from quantum to classical is still not completely understood till date, there
are two assumptions made in the inflationary paradigm in this regard:
  (i) the modes (metric perturbations or fluctuations) behave classically once
they are well outside the Hubble radius and,
  (ii) once they become classical they stay classical and hence can be
described by standard perturbation theory after they re-enter the Hubble
radius.
  We critically examine these assumptions for the tensor modes of (linear)
metric perturbations in a toy three stage universe with (i) inflation, (ii)
radiation-dominated and (iii) late-time accelerated phases. The
quantum-to-classical transition for these modes is evident from the evolution
of Wigner function in phase space and its peaking on the classical trajectory.
However, a better approach to quantify the degree of classicality and study its
evolution was given by Mahajan and Padmanabhan [1] using a classicality
parameter constructed from the parameters of the Wigner function. We study the
evolution of the classicality parameter across the three phases and it turns
out that the first assumption holds true, there is emergence of classicality on
Hubble exit, however the latter assumption of "once classical, always
classical" seems to lie on a shaky ground.


title:
Transition Forests: Learning Discriminative Temporal Transitions for
  Action Recognition and Detection

abstract:
  A human action can be seen as transitions between one's body poses over time,
where the transition depicts a temporal relation between two poses. Recognizing
actions thus involves learning a classifier sensitive to these pose transitions
as well as to static poses. In this paper, we introduce a novel method called
transitions forests, an ensemble of decision trees that both learn to
discriminate static poses and transitions between pairs of two independent
frames. During training, node splitting is driven by alternating two criteria:
the standard classification objective that maximizes the discrimination power
in individual frames, and the proposed one in pairwise frame transitions.
Growing the trees tends to group frames that have similar associated
transitions and share same action label incorporating temporal information that
was not available otherwise. Unlike conventional decision trees where the best
split in a node is determined independently of other nodes, the transition
forests try to find the best split of nodes jointly (within a layer) for
incorporating distant node transitions. When inferring the class label of a new
frame, it is passed down the trees and the prediction is made based on previous
frame predictions and the current one in an efficient and online manner. We
apply our method on varied skeleton action recognition and online detection
datasets showing its suitability over several baselines and state-of-the-art
approaches.


title: Magnetic Hamiltonian Monte Carlo

abstract:
  Hamiltonian Monte Carlo (HMC) exploits Hamiltonian dynamics to construct
efficient proposals for Markov chain Monte Carlo (MCMC). In this paper, we
present a generalization of HMC which exploits \textit{non-canonical}
Hamiltonian dynamics. We refer to this algorithm as magnetic HMC, since in 3
dimensions a subset of the dynamics map onto the mechanics of a charged
particle coupled to a magnetic field. We establish a theoretical basis for the
use of non-canonical Hamiltonian dynamics in MCMC, and construct a symplectic,
leapfrog-like integrator allowing for the implementation of magnetic HMC.
Finally, we exhibit several examples where these non-canonical dynamics can
lead to improved mixing of magnetic HMC relative to ordinary HMC.


title: Remarks on the treatments of non-solvable potentials

abstract:
  The recently introduced scheme [20,21] is extended to propose an algebraic
non-perturbative approach for the analytical treatment of Schr\"odinger
equations with non-solvable potentials involving an exactly solvable potential
form together with an additional piece. As an illustration the procedure is
successfully applied to the Cornell potential by means of very simple algebraic
manipulations. However, instead of providing numerical eigenvalues for the only
consideration of the small strength of the related linear potential as in the
previous reports, the present model puts forward a clean route to interpret
related experimental or precise numerical results involving wide range of the
linear potential strengths. We hope this new technique will shed some light on
the questions concerning with the limitations of the traditional perturbation
techniques.


title: The anomalous dimension of spin-1/2 baryons in many flavors QCD

abstract:
  The anomalous dimension of spin-1/2 baryon operators in QCD is derived at
leading 1/Nf order using the minimal subtraction scheme. A residual ambiguity,
originating from the presence of evanescent operators in dimensional
regularization, is parametrized by a function of the renormalized coupling. Our
result is shown to agree with previous 2 and 3 loop calculations performed in
two different renormalization schemes.


title:
On logarithmic Sobolev inequalities for the heat kernel on the
  Heisenberg group

abstract:
  In this note, we derive a new logarithmic Sobolev inequality for the heat
kernel on the Heisenberg group. The proof is inspired from the historical
method of Leonard Gross with the Central Limit Theorem for a random walk. Here
the non commutative nature of the increments produces a new gradient which
naturally involves a Brownian bridge on the Heisenberg group. This new
inequality contains the optimal logarithmic Sobolev inequality for the Gaussian
distribution in two dimensions. We compare this new inequality with the
sub-elliptic logarithmic Sobolev inequality of Hong-Quan Li and with the more
recent inequality of Fabrice Baudoin and Nicola Garofalo obtained using a
generalized curvature criterion. Finally, we extend this inequality to the case
of homogeneous Carnot groups of rank two.


title: Remarks on the Woods-Saxon Potential

abstract:
  More recently, comprehensive application results of approximate analytical
solutions of the Woods-Saxon potential in closed form for the 5-dimensional
Bohr Hamiltonian have been appeared [14] and its comparison to the data for
many different nuclei has clearly revealed the domains for the sucsess and
failure in case of using such potential forms to analyse the data concerning
with the nuclear structure of deformed nuclei within the frame of the
collective model. Gaining confidence from this work, exact solvability of the
Woods-Saxon type potentials in lower dimensions for the bound states having
zero angular momentum is carefully reviewed to finalize an ongoing discussion
in the related literature and clearly shown that such kind of potentials have
no analytical solutions even for l=0 case.


title:
Information uncertainty related to marked random times and optimal
  investment

abstract:
  We study an optimal investment problem under default risk where related
information such as loss or recovery at default is considered as an exogenous
random mark added at default time. Two types of agents who have different
levels of information are considered. We first make precise the insider's
information flow by using the theory of enlargement of filtrations and then
obtain explicit logarithmic utility maximization results to compare optimal
wealth for the insider and the ordinary agent. MSC: 60G20, 91G40, 93E20


title:
Applied Lyapunov Stability on Output Tracking Problem for a Class of
  Discrete-Time Linear Systems

abstract:
  The robust tracking and model following problem of linear discrete-time
systems is investigated in this paper. An approach to design robust tracking
controllers is proposed. The system is controlled to track dynamic inputs
generated from a reference model. By using the solution of the Lyapunov
equation, the convergence of the tracking error to the origin, is proved. The
proposed approach employs linear controllers rather than nonlinear ones.
Therefore, the designing method is simple for use and the resulting controller
is easy to implement. An application of the proposed approach for a class of
perturbed systems is also considered. Finally, numerical examples are given to
demonstrate the validity of the results.


title:
How to use the functional empirical process for deriving asymptotic laws
  for functions of the sample

abstract:
  The functional empirical process is a very powerful tool for deriving
asymptotic laws for almost any kind of statistics whenever we know how to
express them into functions of the sample. Since this method seems to be
applied more and more in the very recent future, this paper is intended to
provide a complete but short description and justification of the method and to
illustrate it with a non-trivial example using bivariate data. It may also
serve for citation without repeating the arguments.


title:
Resonance identity and multiplicity of non-contractible closed geodesics
  on Finsler $\mathbb{R}P^{n}$

abstract:
  In this paper, we establish first the resonance identity for non-contractible
homologically visible prime closed geodesics on Finsler $n$-dimensional real
projective space $(\mathbb{R}P^n,F)$ when there exist only finitely many
distinct non-contractible closed geodesics on $(\mathbb{R}P^n,F)$, where the
integer $n\geq2$. Then as an application of this resonance identity, we prove
the existence of at least two distinct non-contractible closed geodesics on
$\mathbb{R}P^{n}$ with a bumpy and irreversible Finsler metric. Together with
two previous results on bumpy and reversible Finsler metrics in \cite{DLX2015}
and \cite{Tai2016}, it yields that every $\mathbb{R}P^{n}$ with a bumpy Finsler
metric possesses at least two distinct non-contractible closed geodesics.


title: GRBs as Probes of the IGM

abstract:
  Gamma-ray Bursts (GRBs) are the most powerful explosions known, capable of
outshining the rest of gamma-ray sky during their short-lived prompt emission.
Their cosmological nature makes them the best tool to explore the final stages
in the lives of very massive stars up to the highest redshifts. Furthermore,
studying the emission from their low-energy counterparts (optical and infrared)
via rapid spectroscopy, we have been able to pin down the exact location of the
most distant galaxies as well as placing stringent constraints on their host
galaxies and intervening systems at low and high-redshift (e.g. metallicity and
neutral hydrogen fraction). In fact, each GRB spectrum contains absorption
features imprinted by metals in the host interstellar medium (ISM) as well as
the intervening intergalactic medium (IGM) along the line of sight. In this
chapter we summarize the progress made using a large dataset of GRB spectra in
understanding the nature of both these absorbers and how GRBs can be used to
study the early Universe, in particular to measure the neutral hydrogen
fraction and the escape fraction of UV photons before and during the epoch of
re-ionization.


title: Adversarial Training For Sketch Retrieval

abstract:
  Generative Adversarial Networks (GAN) are able to learn excellent
representations for unlabelled data which can be applied to image generation
and scene classification. Representations learned by GANs have not yet been
applied to retrieval. In this paper, we show that the representations learned
by GANs can indeed be used for retrieval. We consider heritage documents that
contain unlabelled Merchant Marks, sketch-like symbols that are similar to
hieroglyphs. We introduce a novel GAN architecture with design features that
make it suitable for sketch retrieval. The performance of this sketch-GAN is
compared to a modified version of the original GAN architecture with respect to
simple invariance properties. Experiments suggest that sketch-GANs learn
representations that are suitable for retrieval and which also have increased
stability to rotation, scale and translation compared to the standard GAN
architecture.