title: Dual polynomial spline bases

abstract:
  In the paper, we give methods of construction of dual bases for the B-spline
basis and truncated power basis. Explicit formulas for the dual B-spline basis
are obtained using the Legendre-like orthogonal basis of the polynomial spline
space presented in (Wei et al., Comput.-Aided Des. 45 (2013), 85-92) and a
connection between orthogonal and dual bases of any space given in (Lewanowicz
and Wo\'zny, J. Approx. Theory 138 (2006), 129-150). Construction of the dual
truncated power basis is performed in two phases. We start with explicit
formulas for the dual power basis of the space of polynomials. Then, we expand
this basis using an iterative algorithm proposed in (Wo\'zny, J. Comput. Appl.
Math. 260 (2014), 301-311). As a result, we obtain the dual truncated power
basis. We also present some applications of the proposed dual polynomial spline
bases and illustrative examples.


title: Residue Formulas for logarithmic Foliations and applications

abstract:
  In this work we prove a Baum-Bott type formula for non-compact complex
manifold of the form $\tilde{X}=X- \mathcal{D}$, where $X$ is a complex compact
manifold and $\mathcal{D}$ is a normal crossing divisor on $X$. As
applications, we provide a Poincar\'e-Hopf type Theorem and an optimal
description for a smooth hypersurface $\mathcal{D}$ invariant by an
one-dimensional foliation $\mathscr F$ on $\mathbb{P}^n$ satisfying
$Sing(\mathscr F) \subsetneq \mathcal{D}.$


title: Real topological cyclic homology of spherical group rings

abstract:
  We compute the $G$-equivariant homotopy type of the real topological cyclic
homology of spherical group rings with anti-involution induced by taking
inverses in the group, where $G$ denotes the group
$Gal(\mathbb{C}/\mathbb{R})$. The real topological Hochschild homology of a
spherical group ring $\mathbb{S}[\Gamma]$, with anti-involution as described,
is an $O(2)$-cyclotomic spectrum and we construct a map commuting with the
cyclotomic structures from the $O(2)$-equivariant suspension spectrum of the
dihedral bar construction on $\Gamma$ to the real topological Hochschild
homology of $\mathbb{S}[\Gamma]$, which induce isomorphisms on $C_{p^n}$- and
$D_{p^n}$-homotopy groups for all $n\in \mathbb{Z}$ and all primes $p$. Here
$C_{p^n}$ is the cyclic group of order $p^n$ and $D_{p^n}$ is the dihedral
group of order $2p^n$. Finally, we compute the $G$-equivariant homotopy type of
the real topological cyclic homology of $\mathbb{S}[\Gamma]$ at a prime $p$.


title:
Posterior Graph Selection and Estimation Consistency for
  High-dimensional Bayesian DAG Models

abstract:
  Covariance estimation and selection for high-dimensional multivariate
datasets is a fundamental problem in modern statistics. Gaussian directed
acyclic graph (DAG) models are a popular class of models used for this purpose.
Gaussian DAG models introduce sparsity in the Cholesky factor of the inverse
covariance matrix, and the sparsity pattern in turn corresponds to specific
conditional independence assumptions on the underlying variables. A variety of
priors have been developed in recent years for Bayesian inference in DAG
models, yet crucial convergence and sparsity selection properties for these
models have not been thoroughly investigated. Most of these priors are
adaptations or generalizations of the Wishart distribution in the DAG context.
In this paper, we consider a flexible and general class of these 'DAG-Wishart'
priors with multiple shape parameters. Under mild regularity assumptions, we
establish strong graph selection consistency and establish posterior
convergence rates for estimation when the number of variables p is allowed to
grow at an appropriate sub-exponential rate with the sample size n.


title:
Development of a Depleted Monolithic CMOS Sensor in a 150 nm CMOS
  Technology for the ATLAS Inner Tracker Upgrade

abstract:
  The recent R&D focus on CMOS sensors with charge collection in a depleted
zone has opened new perspectives for CMOS sensors as fast and radiation hard
pixel devices. These sensors, labelled as depleted CMOS sensors (DMAPS), have
already shown promising performance as feasible candidates for the ATLAS Inner
Tracker (ITk) upgrade, possibly replacing the current passive sensors. A
further step to exploit the potential of DMAPS is to investigate the
suitability of equipping the outer layers of the ATLAS ITk upgrade with fully
monolithic CMOS sensors. This paper presents the development of a depleted
monolithic CMOS pixel sensor designed in the LFoundry 150 nm CMOS technology,
with the focus on design details and simulation results.


title: On Variations Of Pre-Supernova Model Properties

abstract:
  We explore the variation in single star 15-30 $\rm{M}_{\odot}$, non-rotating,
solar metallicity, pre-supernova MESA models due to changes in the number of
isotopes in a fully-coupled nuclear reaction network and adjustments in the
mass resolution. Within this two-dimensional plane we quantitatively detail the
range of core masses at various stages of evolution, mass locations of the main
nuclear burning shells, electron fraction profiles, mass fraction profiles,
burning lifetimes, stellar lifetimes, and compactness parameter at
core-collapse for models with and without mass loss. Up to carbon burning we
generally find mass resolution has a larger impact on the variations than the
number of isotopes, while the number of isotopes plays a more significant role
in determining the span of the variations for neon, oxygen and silicon burning.
Choice of mass resolution dominates the variations in the structure of the
intermediate convection zone and secondary convection zone during core and
shell hydrogen burning respectively, where we find a minimum mass resolution of
$\approx$ 0.01 $\rm{M}_{\odot}$ is necessary to achieve convergence in the
helium core mass at the $\approx$5% level. On the other hand, at the onset of
core-collapse we find $\approx$30% variations in the central electron fraction
and mass locations of the main nuclear burning shells, a minimum of
$\approx$127 isotopes is needed to attain convergence of these values at the
$\approx$10% level.


title: Viscosity effects in wind wave generation

abstract:
  We investigate experimentally the influence of the liquid viscosity on the
problem of the generation of waves by a turbulent wind at the surface of a
liquid, extending the results of Paquier, Moisy and Rabaud [Phys. Fluids {\bf
27}, 122103 (2015)] over nearly three decades of viscosity. The surface
deformations are measured with micrometer accuracy using the Free-Surface
Synthetic Schlieren method. We recover the two regimes of surface deformations
previously identified: the wrinkles regime at small wind velocity, resulting
from the viscous imprint on the liquid surface of the turbulent fluctuations in
the boundary layer, and the regular wave regime at large wind velocity. Below
the wave threshold, we find that the characteristic amplitude of the wrinkles
scales as $\nu^{-1/2} u^{* 3/2}$ over nearly the whole range of viscosities,
whereas their size are essentially unchanged. We propose a simple model for
this scaling, which compares well with the data. We finally show that the
critical friction velocity $u^*$ for the onset of regular waves slowly
increases with viscosity as $\nu^{0.2}$. Whereas the transition between
wrinkles and waves is smooth at small viscosity, including for water, it
becomes rather abrupt at large viscosity. Finally, a new regime is found at
$\nu > 100-200 \times 10^{-6}$~m$^2$~s$^{-1}$, characterized by a slow, nearly
periodic emission of large-amplitude isolated fluid bumps.


title: Koopman principle eigenfunctions and linearization of diffeomorphisms

abstract:
  This paper considers a nonlinear dynamical system on a complex, finite
dimensional Banach space which has an asymptotically stable, hyperbolic fixed
point. We investigate the connection between the so-called principle
eigenfunctions of the Koopman operator and the existence of a topological
conjugacy between the nonlinear dynamics and its linearization in the
neighborhood of the fixed point. The principle eigenfunctions generate an
algebra of observables for the linear dynamics --- called the principle algebra
--- which can be used to generate a sequence of approximate conjugacy maps in
the same manner as it is done in normal form theory. Each element of the
principle algebra has an expansion into eigenfunctions of the Koopman operator
and composing an eigenfunction with one of the approximate topological
conjugacies gives an approximate eigenfunction of the Koopman operator
associated with the nonlinear dynamical system. When the limit of the
approximate conjugacies exists and attention is restricted to real Banach
spaces, a simple application of the Stone-Weierstrass theorem shows that both
the principle algebra and the pull-back algebra --- defined by composing the
principle algebra with the topological conjugacy --- are uniformly dense in
either the space of continuous functions or the maximal ideal of continuous
functions vanishing at the fixed point. The point is that, a priori, it is
difficult to know which space of observables to use for dissipative nonlinear
dynamical systems whose elements have spectral expansions into eigenfunctions.
These results say that any continuous observable is arbitrarily close to one
that has such an expansion.


title: Near-Optimal Disjoint-Path Facility Location Through Set Cover by Pairs

abstract:
  In this paper we consider two special cases of the "cover-by-pairs"
optimization problem that arise when we need to place facilities so that each
customer is served by two facilities that reach it by disjoint shortest paths.
These problems arise in a network traffic monitoring scheme proposed by Breslau
et al. and have potential applications to content distribution. The
"set-disjoint" variant applies to networks that use the OSPF routing protocol,
and the "path-disjoint" variant applies when MPLS routing is enabled, making
better solutions possible at the cost of greater operational expense. Although
we can prove that no polynomial-time algorithm can guarantee good solutions for
either version, we are able to provide heuristics that do very well in practice
on instances with real-world network structure. Fast implementations of the
heuristics, made possible by exploiting mathematical observations about the
relationship between the network instances and the corresponding instances of
the cover-by-pairs problem, allow us to perform an extensive experimental
evaluation of the heuristics and what the solutions they produce tell us about
the effectiveness of the proposed monitoring scheme. For the set-disjoint
variant, we validate our claim of near-optimality via a new lower-bounding
integer programming formulation. Although computing this lower bound requires
solving the NP-hard Hitting Set problem and can underestimate the optimal value
by a linear factor in the worst case, it can be computed quickly by CPLEX, and
it equals the optimal solution value for all the instances in our extensive
testbed.


title: Combating Reinforcement Learning's Sisyphean Curse with Intrinsic Fear

abstract:
  Many practical environments contain catastrophic states that an optimal agent
would visit infrequently or never. Even on toy problems, Deep Reinforcement
Learning (DRL) agents tend to periodically revisit these states upon forgetting
their existence under a new policy. We introduce intrinsic fear (IF), a learned
reward shaping that guards DRL agents against periodic catastrophes. IF agents
possess a fear model trained to predict the probability of imminent
catastrophe. This score is then used to penalize the Q-learning objective. Our
theoretical analysis bounds the reduction in average return due to learning on
the perturbed objective. We also prove robustness to classification errors. As
a bonus, IF models tend to learn faster, owing to reward shaping. Experiments
demonstrate that intrinsic-fear DQNs solve otherwise pathological environments
and improve on several Atari games.


title:
Tricritical wings and modulated magnetic phases in LaCrGe$ _{3}$ under
  pressure

abstract:
  We determined on the temperature-pressure-magnetic field ($T$-$p$-$H$) phase
diagram of the ferromagnet LaCrGe$_3$ from electrical resistivity measurements
on single crystals. In ferromagnetic systems, quantum criticality is avoided
either by a change of the transition order, becoming of the first order at a
tricritical point, or by the appearance of modulated magnetic phases. In the
first case, the application of a magnetic field reveals a wing-structure phase
diagram as seen in itinerant ferromagnets such as ZrZn$_2$ and UGe$_2$. In the
second case, no tricritical wings have been observed so far. Our investigation
of LaCrGe$_3$ reveals a double-wing structure indicating strong similarities
with ZrZn$_2$ and UGe$_2$. But, unlike these, simpler systems, LaCrGe$_3$ is
thought to exhibit a modulated magnetic phase under pressure which already
precludes it from a pressure-driven paramagnetic-ferromagnetic quantum phase
transition in zero field. As a result, the $T$-$p$-$H$ phase diagram of
LaCrGe$_3$ shows both the wing structure as well as the appearance of new
magnetic phases, providing the first example of this new possibility for the
phase diagram of metallic quantum ferromagnets.


title:
Bayesian and Variational Bayesian approaches for flows in heterogenous
  random media

abstract:
  In this paper, we study porous media flows in heterogeneous stochastic media.
We propose an efficient forward simulation technique that is tailored for
variational Bayesian inversion. As a starting point, the proposed forward
simulation technique decomposes the solution into the sum of separable
functions (with respect to randomness and the space), where each term is
calculated based on a variational approach. This is similar to Proper
Generalized Decomposition (PGD). Next, we apply a multiscale technique to solve
for each term and, further, decompose the random function into 1D fields. As a
result, our proposed method provides an approximation hierarchy for the
solution as we increase the number of terms in the expansion and, also,
increase the spatial resolution of each term. We use the hierarchical solution
distributions in a variational Bayesian approximation to perform uncertainty
quantification in the inverse problem. We conduct a detailed numerical study to
explore the performance of the proposed uncertainty quantification technique
and show the theoretical posterior concentration.


title: Jordan Trialgebras and Post-Jordan Algebras

abstract:
  We compute minimal sets of generators for the S_n-modules (n <= 4) of
multilinear polynomial identities of arity n satisfied by the Jordan product
and the Jordan diproduct (resp. pre-Jordan product) in every triassociative
(resp. tridendriform) algebra. These identities define Jordan trialgebras and
post-Jordan algebras: Jordan analogues of the Lie trialgebras and post-Lie
algebras introduced by Dotsenko et al., Pei et al., Vallette & Loday. We
include an extensive review of analogous structures existing in the literature,
and their interrelations, in order to identify the gaps filled by our two new
varieties of algebras. We use computer algebra (linear algebra over finite
fields, representation theory of symmetric groups), to verify in both cases
that every polynomial identity of arity <= 6 is a consequence of those of arity
<= 4. We conjecture that in both cases the next independent identities have
arity 8, imitating the Glennie identities for Jordan algebras. We formulate our
results as a commutative square of operad morphisms, which leads to the
conjecture that the squares in a much more general class are also commutative.


title: Symbolic Integration in Prime Characteristic

abstract:
  In this paper we study elementary extensions of differential fields in prime
characteristic. In particular, we show that, in contrast to Liouville's result
in characteristic zero, all elements of an elementary extension admit an
antiderivative in some logarithmic extension.


title: Maximal subgroups of groups of intermediate growth

abstract:
  Finding the number of maximal subgroups of infinite index of a finitely
generated group is a natural problem that has been solved for several classes
of `geometric' groups (linear groups, hyperbolic groups, mapping class groups,
etc). Here we provide a solution for a family of groups with a different
geometric origin: groups of intermediate growth that act on rooted binary
trees. In particular, we show that the non-torsion iterated monodromy groups of
the tent map (a special case of some groups first introduced by {\v{S}}uni{\'c}
in \cite{Sunic} as `siblings of the Grigorchuk group') have exactly countably
many maximal subgroups of infinite index, and describe them up to conjugacy.
This is in contrast to the torsion case (e.g. Grigorchuk group) where there are
no maximal subgroups of infinite index. It is also in contrast to the
above-mentioned geometric groups, where there are either none or uncountably
many such subgroups.
  Along the way we show that all the groups defined by {\v{S}}uni{\'c} have the
congruence subgroup property and are just infinite.


title: The structural elements of the cosmic web

abstract:
  In 1970 Zel'dovich published a far-reaching paper presenting a simple
equation describing the nonlinear growth of primordial density inhomogeneities.
The equation was remarkably successful in explaining the large scale structure
in the Universe that we observe: a Universe in which the structure appears to
be delineated by filaments and clusters of galaxies surrounding huge void
regions. In order to concretise this impression it is necessary to define these
structural elements through formal techniques with which we can compare the
Zel'dovich model and N-body simulations with the observational data.
  We present an overview of recent efforts to identify voids, filaments and
clusters in both the observed galaxy distribution and in numerical simulations
of structure formation. We focus, in particular, on methods that involve no
fine-tuning of parameters and that handle scale dependence automatically. It is
important that these techniques should result in finding structures that relate
directly to the dynamical mechanism of structure formation.


title: Electromagnetically Induced Transparency and Quantum Heat Engines

abstract:
  We describe how electromagnetically induced transparency may be used to
construct a non-traditional near-ideal quantum heat engine as constrained by
the Second Law. The engine is pumped by a thermal reservoir that may be either
hotter or colder than that of an exhaust reservoir, and also by a monochromatic
laser. As output, it produces a bright narrow emission at line center of an
otherwise absorbing transition.


title:
Degeneracy-preserving quantum non-demolition measurement of parity-type
  observables for cat-qubits

abstract:
  A central requirement for any quantum error correction scheme is the ability
to perform quantum non-demolition measurements of an error syndrome,
corresponding to a special symmetry property of the encoding scheme. It is in
particular important that such a measurement does not introduce extra error
mechanisms, not included in the error model of the correction scheme. In this
letter, we ensure such a robustness by designing an interaction with a
measurement device that preserves the degeneracy of the measured observable.
More precisely, we propose a scheme to perform continuous and quantum
non-demolition measurement of photon-number parity in a microwave cavity. This
corresponds to the error syndrome in a class of error correcting codes called
the cat-codes, which have recently proven to be efficient and versatile for
quantum information processing. In our design, we exploit the strongly
nonlinear Hamiltonian of a high-impedance Josephson circuit, coupling a high-Q
cavity storage cavity mode to a low-Q readout one. By driving the readout
resonator at its resonance, the phase of the reflected/transmitted signal
carries directly exploitable information on parity-type observables for encoded
cat-qubits of the high-Q mode.


title: Bayesian Cosmic Web Reconstruction: BARCODE for Clusters

abstract:
  We describe the Bayesian BARCODE formalism that has been designed towards the
reconstruction of the Cosmic Web in a given volume on the basis of the sampled
galaxy cluster distribution. Based on the realization that the massive compact
clusters are responsible for the major share of the large scale tidal force
field shaping the anisotropic and in particular filamentary features in the
Cosmic Web. Given the nonlinearity of the constraints imposed by the cluster
configurations, we resort to a state-of-the-art constrained reconstruction
technique to find a proper statistically sampled realization of the original
initial density and velocity field in the same cosmic region. Ultimately, the
subsequent gravitational evolution of these initial conditions towards the
implied Cosmic Web configuration can be followed on the basis of a proper
analytical model or an N-body computer simulation. The BARCODE formalism
includes an implicit treatment for redshift space distortions. This enables a
direct reconstruction on the basis of observational data, without the need for
a correction of redshift space artifacts. In this contribution we provide a
general overview of the the Cosmic Web connection with clusters and a
description of the Bayesian BARCODE formalism. We conclude with a presentation
of its successful workings with respect to test runs based on a simulated large
scale matter distribution, in physical space as well as in redshift space.


title:
The Zeldovich & Adhesion approximations, and applications to the local
  universe

abstract:
  The Zeldovich approximation (ZA) predicts the formation of a web of
singularities. While these singularities may only exist in the most formal
interpretation of the ZA, they provide a powerful tool for the analysis of
initial conditions. We present a novel method to find the skeleton of the
resulting cosmic web based on singularities in the primordial deformation
tensor and its higher order derivatives. We show that the A_3-lines predict the
formation of filaments in a two-dimensional model. We continue with
applications of the adhesion model to visualise structures in the local (z <
0.03) universe.


title: Voids and the Cosmic Web: cosmic depressions & spatial complexity

abstract:
  Voids form a prominent aspect of the Megaparsec distribution of galaxies and
matter. Not only do they represent a key constituent of the Cosmic Web, they
also are one of the cleanest probes and measures of global cosmological
parameters. The shape and evolution of voids are highly sensitive to the nature
of dark energy, while their substructure and galaxy population provides a
direct key to the nature of dark matter. Also, the pristine environment of void
interiors is an important testing ground for our understanding of environmental
influences on galaxy formation and evolution. In this paper, we review the key
aspects of the structure and dynamics of voids, with a particular focus on the
hierarchical evolution of the void population. We demonstrate how the rich
structural pattern of the Cosmic Web is related to the complex evolution and
buildup of voids.


title: Direct integral description of angulon

abstract:
  We propose a representation of angulon in which the angulon operator is
decomposable relative to the field of Hilbert spaces over the probability
measure space, and the probability measure corresponds to the total-number
operator of phonons. In this representation we are able to find the system of
$N+1$ equations whose solutions form the eigenspace of the angulon operator,
where $1\leq N<\infty$ is the number of phonon excitations. Using this result
we estimate the infimum of the spectrum. In the special case $N=1$, the lowest
energy approximates to the value which is already known in the literature. Our
findings indicate that two-phonon excitations ($N=2$) contribute notably to the
energy of a molecule in superfluid $^4$He.


title: Sample Efficient Actor-Critic with Experience Replay

abstract:
  This paper presents an actor-critic deep reinforcement learning agent with
experience replay that is stable, sample efficient, and performs remarkably
well on challenging environments, including the discrete 57-game Atari domain
and several continuous control problems. To achieve this, the paper introduces
several innovations, including truncated importance sampling with bias
correction, stochastic dueling network architectures, and a new trust region
policy optimization method.


title: Can we 'future-proof' consensus trees?

abstract:
  Consensus methods are widely used for combining phylogenetic trees into a
single estimate of the evolutionary tree for a group of species. As more taxa
are added, the new source trees may begin to tell a different evolutionary
story when restricted to the original set of taxa. However, if the new trees,
restricted to the original set of taxa, were to agree exactly with the earlier
trees, then we might hope that their consensus would either agree with or
resolve the original consensus tree. In this paper, we ask under what
conditions consensus methods exist that are 'future proof' in this sense. While
we show that some methods (e.g. Adams consensus) have this property for
specific types of input, we also establish a rather surprising `no-go' theorem:
there is no 'reasonable' consensus method that satisfies the future-proofing
property in general. We then investigate a second notion of 'future proofing'
for consensus methods, in which trees (rather than taxa) are added, and
establish some positive and negative results. We end with some questions for
future work.


title: Generalized noise terms for the quantized fluctuational electrodynamics

abstract:
  The quantization of optical fields in vacuum has been known for decades, but
extending the field quantization to lossy and dispersive media in
nonequilibrium conditions has proven to be complicated due to the
position-dependent electric and magnetic responses of the media. In fact,
consistent position-dependent quantum models for the photon number in resonant
structures have only been formulated very recently and only for dielectric
media. Here we present a general position-dependent quantized fluctuational
electrodynamics (QFED) formalism that extends the consistent field quantization
to describe the photon number also in the presence of magnetic field-matter
interactions. It is shown that the magnetic fluctuations provide an additional
degree of freedom in media where the magnetic coupling to the field is
prominent. Therefore, the field quantization requires an additional independent
noise operator that is commuting with the conventional bosonic noise operator
describing the polarization current fluctuations in dielectric media. In
addition to allowing the detailed description of field fluctuations, our
methods provide practical tools for modeling optical energy transfer and the
formation of thermal balance in general dielectric and magnetic nanodevices. We
use the QFED to investigate the magnetic properties of microcavity systems to
demonstrate an example geometry in which it is possible to probe fields arising
from the electric and magnetic source terms. We show that, as a consequence of
the magnetic Purcell effect, the tuning of the position of an emitter layer
placed inside a vacuum cavity can make the emissivity of a magnetic emitter to
exceed the emissivity of a corresponding electric emitter.


title: Scalable synchronization of spin-Hall oscillators in out-of-plane field

abstract:
  A strategy for a scalable synchronization of an array of spin-Hall
oscillators (SHOs) is illustrated. In detail, we present micromagnetic
simulations of two and five SHOs realized by means of couples of triangular
golden contacts on the top of a Pt/CoFeB/Ta trilayer. Results highlight that
the synchronization occurs for the whole current region that gives rise to the
excitation of self-oscillations. This is linked to the role of the
magnetodipolar coupling, which is the phenomenon driving the synchronization
when the distance between oscillators is not too large. Synchronization turns
out to be also robust against geometrical differences of the contacts,
simulated by considering variable distances between the tips ranging from 100nm
to 200nm. Besides, it entails an enlargement of the radiation pattern that can
be useful for the generation of spin-waves in magnonics applications.
Simulations performed to study the effect of the interfacial
Dzyaloshinskii-Moriya interaction show nonreciprocity in spatial propagation of
the synchronized spin-wave. The simplicity of the geometry and the robustness
of the achieved synchronization make this design of array of SHOs scalable for
a larger number of synchronized oscillators.


title: URL ordering policies for distributed crawlers: a review

abstract:
  With the increase in size of web, the information is also spreading at large
scale. Search Engines are the medium to access this information. Crawler is the
module of search engine which is responsible for download the web pages. In
order to download the fresh information and get the database rich, crawler
should crawl the web in some order. This is called as ordering of URLs. URL
ordering should be done in efficient and effective manner in order to crawl the
web in proficient manner. In this paper, a survey is done on some existing
methods of URL ordering and at the end of this paper comparison is also carried
out among them.


title: 4d SCFTs from negative-degree line bundles

abstract:
  We construct 4d $\mathcal{N}=1$ quantum field theories by compactifying the
(2,0) theories on a Riemann surface with genus $g$ and $n$ punctures, where the
normal bundle decomposes into a sum of two line bundles with possibly negative
degrees $p$ and $q$. Until recently, the only available field-theoretic
constructions required the line bundle degrees to be nonnegative, although
supergravity solutions were constructed in the literature for the zero-puncture
case for all $p$ and $q$. Here, we provide field-theoretic constructions and
computations of the central charges of 4d $\mathcal{N}=1$ SCFTs that are the IR
limit of M5-branes wrapping a surface with general $p$ or $q$ negative, for
general genus $g$ and number of maximal punctures $n$.


title: Bayesian Optical Flow with Uncertainty Quantification

abstract:
  Optical flow refers to the visual motion observed between two consecutive
images. Since the degree of freedom is typically much larger than the
constraints imposed by the image observations, the straightforward formulation
of optical flow as an inverse problem is ill-posed. Standard approaches to
determine optical flow rely on formulating and solving an optimization problem
that contains both a data fidelity term and a regularization term, the latter
effectively resolves the otherwise ill-posedness of the inverse problem. In
this work, we depart from the deterministic formalism, and instead treat
optical flow as a statistical inverse problem. We discuss how a classical
optical flow solution can be interpreted as a point estimate in this more
general framework. The statistical approach, whose "solution" is a distribution
of flow fields, which we refer to as Bayesian optical flow, allows not only
"point" estimates (e.g., the computation of average flow field), but also
statistical estimates (e.g., quantification of uncertainty) that are beyond any
standard method for optical flow. As application, we benchmark Bayesian optical
flow together with uncertainty quantification using several types of prescribed
ground-truth flow fields and images.


title: Asymmetric truncated Toeplitz operators on finite-dimensional spaces II

abstract:
  In this paper we present some consequences of the description of matrix
representations of asymmetric truncated Toeplitz operators acting between
finite-dimensional model spaces. In particular, we prove that these operators
can be characterized using modified compressed shifts or the notion of shift
invariance. We also describe rank-one asymmetric truncated Toeplitz operators
acting between finite-dimensional model spaces. This paper is a sequel to the
paper of J. Jurasik and B. {\L}anucha "Asymmetric truncated Toeplitz operators
on finite-dimensional spaces".


title: Deep Information Propagation

abstract:
  We study the behavior of untrained neural networks whose weights and biases
are randomly distributed using mean field theory. We show the existence of
depth scales that naturally limit the maximum depth of signal propagation
through these random networks. Our main practical result is to show that random
networks may be trained precisely when information can travel through them.
Thus, the depth scales that we identify provide bounds on how deep a network
may be trained for a specific choice of hyperparameters. As a corollary to
this, we argue that in networks at the edge of chaos, one of these depth scales
diverges. Thus arbitrarily deep networks may be trained only sufficiently close
to criticality. We show that the presence of dropout destroys the
order-to-chaos critical point and therefore strongly limits the maximum
trainable depth for random networks. Finally, we develop a mean field theory
for backpropagation and we show that the ordered and chaotic phases correspond
to regions of vanishing and exploding gradient respectively.


title:
Cross-plane enhanced thermoelectricity and phonon suppression in
  graphene/MoS2 van der Waals heterostructures

abstract:
  The thermoelectric figures of merit of pristine two-dimensional materials are
predicted to be significantly less than unity, making them uncompetitive as
thermoelectric materials. Here we elucidate a new strategy that overcomes this
limitation by creating multi-layer nanoribbons of two different materials and
allowing thermal and electrical currents to flow perpendicular to their planes.
To demonstrate this enhancement of thermoelectric efficiency ZT, we analyse the
thermoelectric performance of monolayer molybdenum disulphide (MoS2) sandwiched
between two graphene monolayers and demonstrate that the cross-plane (CP) ZT is
significantly enhanced compared with the pristine parent materials. For the
parent monolayer of MoS2, we find that ZT can be as high as approximately 0.3,
whereas monolayer graphene has a negligibly small ZT. In contrast for the
graphene/MoS2/graphene heterostructure, we find that the CP ZT can be as large
as 2.8. One contribution to this enhancement is a reduction of the thermal
conductance of the van der Waals heterostructure compared with the parent
materials, caused by a combination of boundary scattering at the MoS2/graphene
interface which suppresses the phonons transmission and the lower Debye
frequency of monolayer MoS2, which filters phonons from the monolayer graphene.
A second contribution is an increase in the electrical conductance and Seebeck
coefficient associated with molybdenum atoms at the edges of the nanoribbons.


title: Parsec-scale jet properties of the gamma-ray quasar 3C 286

abstract:
  The quasar 3C~286 is one of two compact steep spectrum sources detected by
the {\it Fermi}/LAT. Here, we investigate the radio properties of the
parsec(pc)-scale jet and its (possible) association with the $\gamma$-ray
emission in 3C~286. The Very Long Baseline Interferometry (VLBI) images at
various frequencies reveal a one-sided core--jet structure extending to the
southwest at a projected distance of $\sim$1 kpc. The component at the jet base
showing an inverted spectrum is identified as the core, with a mean brightness
temperature of $2.8\times 10^{9}$~K. The jet bends at about 600 pc (in
projection) away from the core, from a position angle of $-135^\circ$ to
$-115^\circ$. Based on the available VLBI data, we inferred the proper motion
speed of the inner jet as $0.013 \pm 0.011$ mas yr$^{-1}$ ($\beta_{\rm app} =
0.6 \pm 0.5$), corresponding to a jet speed of about $0.5\,c$ at an inclination
angle of $48^\circ$ between the jet and the line of sight of the observer. The
brightness temperature, jet speed and Lorentz factor are much lower than those
of $\gamma$-ray-emitting blazars, implying that the pc-scale jet in 3C~286 is
mildly relativistic. Unlike blazars in which $\gamma$-ray emission is in
general thought to originate from the beamed innermost jet, the location and
mechanism of $\gamma$-ray emission in 3C~286 may be different as indicated by
the current radio data. Multi-band spectrum fitting may offer a complementary
diagnostic clue of the $\gamma$-ray production mechanism in this source.


title:
A Self-Driving Robot Using Deep Convolutional Neural Networks on
  Neuromorphic Hardware

abstract:
  Neuromorphic computing is a promising solution for reducing the size, weight
and power of mobile embedded systems. In this paper, we introduce a realization
of such a system by creating the first closed-loop battery-powered
communication system between an IBM TrueNorth NS1e and an autonomous
Android-Based Robotics platform. Using this system, we constructed a dataset of
path following behavior by manually driving the Android-Based robot along steep
mountain trails and recording video frames from the camera mounted on the robot
along with the corresponding motor commands. We used this dataset to train a
deep convolutional neural network implemented on the TrueNorth NS1e. The NS1e,
which was mounted on the robot and powered by the robot's battery, resulted in
a self-driving robot that could successfully traverse a steep mountain path in
real time. To our knowledge, this represents the first time the TrueNorth NS1e
neuromorphic chip has been embedded on a mobile platform under closed-loop
control.


title: Adversarial Machine Learning at Scale

abstract:
  Adversarial examples are malicious inputs designed to fool machine learning
models. They often transfer from one model to another, allowing attackers to
mount black box attacks without knowledge of the target model's parameters.
Adversarial training is the process of explicitly training a model on
adversarial examples, in order to make it more robust to attack or to reduce
its test error on clean inputs. So far, adversarial training has primarily been
applied to small problems. In this research, we apply adversarial training to
ImageNet. Our contributions include: (1) recommendations for how to succesfully
scale adversarial training to large models and datasets, (2) the observation
that adversarial training confers robustness to single-step attack methods, (3)
the finding that multi-step attack methods are somewhat less transferable than
single-step attack methods, so single-step attacks are the best for mounting
black-box attacks, and (4) resolution of a "label leaking" effect that causes
adversarially trained models to perform better on adversarial examples than on
clean examples, because the adversarial example construction process uses the
true label and the model can learn to exploit regularities in the construction
process.


title: On a conjecture of Hong and Won

abstract:
  We give an explicit counter-example to a conjecture of Kyusik Hong and
Joonyeong Won about $\alpha$-invariants of polarized smooth del Pezzo surfaces
of degree one.


title: Corrected Bayesian information criterion for stochastic block models

abstract:
  Estimating the number of communities is one of the fundamental problems in
community detection. We re-examine the Bayesian paradigm for stochastic block
models and propose a "corrected Bayesian information criterion",to determine
the number of communities and show that the proposed estimator is consistent
under mild conditions. The proposed criterion improves those used in Wang and
Bickel (2016) and Saldana et al. (2017) which tend to underestimate and
overestimate the number of communities, respectively. Along the way, we
establish the Wilks theorem for stochastic block models. Moreover, we show
that, to obtain the consistency of model selection for stochastic block models,
we need a so-called "consistency condition". We also provide sufficient
conditions for both homogenous networks and non-homogenous networks. The
results are further extended to degree corrected stochastic block models.
Numerical studies demonstrate our theoretical results.


title: Reparameterization trick for discrete variables

abstract:
  Low-variance gradient estimation is crucial for learning directed graphical
models parameterized by neural networks, where the reparameterization trick is
widely used for those with continuous variables. While this technique gives
low-variance gradient estimates, it has not been directly applicable to
discrete variables, the sampling of which inherently requires discontinuous
operations. We argue that the discontinuity can be bypassed by marginalizing
out the variable of interest, which results in a new reparameterization trick
for discrete variables. This reparameterization greatly reduces the variance,
which is understood by regarding the method as an application of common random
numbers to the estimation. The resulting estimator is theoretically guaranteed
to have a variance not larger than that of the likelihood-ratio method with the
optimal input-dependent baseline. We give empirical results for variational
learning of sigmoid belief networks.


title: Computer Algebra Derivation of the Bias of Burg Estimators

abstract:
  A symbolic method is discussed which can be used to obtain the asymptotic
bias and variance to order $O(1/n)$ for estimators in stationary time series.
Using this method the bias to $O(1/n)$ of the Burg estimator in AR(1) and AR(2)
models is shown to be equal to that of the least squares estimators in both the
known and unknown mean cases. Previous researchers have only been able to
obtain simulation results for this bias because this problem is too intractable
without using computer algebra.


title: Comparing and weighting imperfect models using D-probabilities

abstract:
  We propose a new approach for assigning weights to models using a
divergence-based method ({\em D-probabilities}), relying on evaluating
parametric models relative to a nonparametric Bayesian reference using
Kullback-Leibler divergence. D-probabilities are useful in goodness-of-fit
assessments, in comparing imperfect models, and in providing model weights to
be used in model aggregation. D-probabilities avoid some of the disadvantages
of Bayesian model probabilities, such as large sensitivity to prior choice, and
tend to place higher weight on a greater diversity of models. In an application
to linear model selection against a Gaussian process reference, we provide
simple analytic forms for routine implementation and show that D-probabilities
automatically penalize model complexity. Some asymptotic properties are
described, and we provide interesting probabilistic interpretations of the
proposed model weights. The framework is illustrated through simulation
examples and an ozone data application.


title:
Answering Complicated Question Intents Expressed in Decomposed Question
  Sequences

abstract:
  Recent work in semantic parsing for question answering has focused on long
and complicated questions, many of which would seem unnatural if asked in a
normal conversation between two humans. In an effort to explore a
conversational QA setting, we present a more realistic task: answering
sequences of simple but inter-related questions. We collect a dataset of 6,066
question sequences that inquire about semi-structured tables from Wikipedia,
with 17,553 question-answer pairs in total. Existing QA systems face two major
problems when evaluated on our dataset: (1) handling questions that contain
coreferences to previous questions or answers, and (2) matching words or
phrases in a question to corresponding entries in the associated table. We
conclude by proposing strategies to handle both of these issues.


title: Are FRB Wandering Narrow Beams?

abstract:
  It is generally assumed that the sources of Fast Radio Bursts radiate roughly
isotropically, so that the observed low duty cycle of any individual source
indicates a similar low duty cycle of its radio-frequency emission. An
alternative hypothesis is that the radiative duty cycle is ${\cal O}(1)$, but
that the radiation is emitted in a beam with a solid angle comparable to the
observed duty cycle, whose direction wanders or sweeps across the sky. This
hypothesis relaxes the extreme power demands of isotropically radiating models
of FRB at the price of multiplying the number of sources. The constraints on
pulsar models are relaxed; rather than being unprecedentedly fast-spinning and
highly-magnetized with short spin-down times, their parameters may be closer to
those of typical radio pulsars. The nanoshots of Galactic pulsars pose
analogous energetic problems that may be resolved if their emission also is
beamed, suggesting a relation between these phenomena, despite their vastly
different energy scales.


title: Extended Vicsek fractals: Laplacian spectra and their applications

abstract:
  Extended Vicsek fractals (EVF) are the structures constructed by introducing
linear spacers into traditional Vicsek fractals. Here we study the Laplacian
spectra of the EVF. In particularly, the recurrence relations for the Laplacian
spectra allow us to obtain an analytic expression for the sum of all inverse
nonvanishing Laplacian eigenvalues. This quantity characterizes the large-scale
properties, such as the gyration radius of the polymeric structures, or the
global mean-first passage time for the random walk processes. Introduction of
the linear spacers leads to local heterogeneities, which reveal themselves, for
example, in the dynamics of EVF under external forces.


title: RBPBind: Quantitative prediction of Protein-RNA Interactions

abstract:
  Summary: We introduce RBPBind, a web-based tool for the quantitative
prediction of RNA-protein interactions. Given a user-specified RNA and a
protein selected from a set of several common RNA-binding proteins, RBPBind
computes the binding curve and effective binding constant of the reaction in
question. The server also computes the probability that, at a given
concentration of protein, a protein molecule will bind to any particular
nucleotide along the RNA. The software for RBPBind is adapted from the Vienna
RNA package, whose source code has been modified to accommodate the effects of
single stranded RNA binding proteins. RBPBind thus fully incorporates the
effect of RNA secondary structure on protein-RNA interactions. Availability:
Our web server is available at http://bioserv.mps.ohio-state.edu/RBPBind


title:
Probabilistic Condition Number Estimates For Real Polynomial Systems I:
  A Broader Family Of Distributions

abstract:
  We consider the sensitivity of real roots of polynomial systems with respect
to perturbations of the coefficients. In particular - for a version of the
condition number defined by Cucker, Krick, Malajovich, and Wschebor - we
establish new probabilistic estimates that allow a much broader family of
measures than considered earlier. We also generalize further by allowing
over-determined systems. Along the way, we derive new Lipshitz estimates for
polynomial maps from R^n to R^m, extending earlier work of Kellog on the case
m=1, which may be of independent interest. In Part II, we study smoothed
complexity and how sparsity (in the sense of restricting which monomial terms
can appear) can help further improve earlier condition number estimates.


title:
The rapidity and thermal motion induced transverse momentum
  distributions of identified charged particles produced in Au-Au collisions at
  RHIC energies

abstract:
  It is widely believed that the quark-gluon plasma (QGP) might be formed in
the current heavy ion collisions. It is also widely recognized that the
relativistic hydrodynamics is one of the best tools for describing the process
of expansion and particlization of QGP. In this paper, by taking into account
the effects of thermal motion, a hydrodynamic model including phase transition
from QGP state to hadronic state is used to analyze the rapidity and transverse
momentum distributions of identified charged particles produced in heavy ion
collisions. A comparison is made between the theoretical results and
experimental data. The theoretical model gives a good description to the
corresponding measurements made in Au-Au collisions at RHIC energies.


title: Brauer p-dimension of complete discretely valued fields

abstract:
  Let K be a complete discretely valued field of characteristic 0 with residue
field k of characteristic p. Let n=[k:k^p] be the p-rank of k. It was proved by
Parimala and Suresh that the Brauer p-dimension of K lies between n/2 and 2n.
For n< 4, we improve the upper bound to n+1 and provide examples to show that
our bound is sharp. For n < 3, we also improve the lower bound to n. For
general $n$, we construct a family of fields K_n with residue fields of p-rank
n, such that K_n admits a central simple algebra D_n of index p^{n+1}. Our
sharp lower bounds for n<3 and upper bounds for n< 4 in combination with the
nature of these examples motivate us to conjecture that the Brauer p-dimension
of such fields always lies between n and n+1.


title: Chemical trends in the Galactic Halo with APOGEE data

abstract:
  The galaxy formation process in the $\Lambda$-Cold Dark Matter scenario can
be constrained from the analysis of stars in the Milky Way's halo system. We
examine the variation of chemical abundances in distant halo stars observed by
the Apache Point Galactic Evolution Experiment (APOGEE), as a function of
distance from the Galactic center ($r$) and iron abundance ([M/H]), in the
range 5 $\lesssim r \lesssim$ 30 kpc and $-2.5 <$ [M/H] $<$ 0.0. We perform a
statistical analysis of the abundance ratios derived by the APOGEE pipeline
(ASPCAP) and distances calculated by several approaches. Our analysis reveals
signatures of a different chemical enrichment between the inner and outer
regions of the halo, with a transition at about 15 kpc. The derived metallicity
distribution function exhibits two peaks, at [M/H] $\sim -1.5$ and $\sim -2.1$,
consistent with previously reported halo metallicity distributions. We obtain a
difference of $\sim 0.1$ dex for $\alpha$-element-to-iron ratios for stars at
$r > 15$ kpc and [M/H] $> -1.1$ (larger in the case of O, Mg and S) with
respect to the nearest halo stars. This result confirms previous claims for
low-$\alpha$ stars found at larger distances. Chemical differences in elements
with other nucleosynthetic origins (Ni, K, Na, and Al) are also detected. C and
N do not provide reliable information about the interstellar medium from which
stars formed because our sample comprises RGB and AGB stars and can experience
mixing of material to their surfaces.


title: Non-spectral problem for the planar self-affine measures

abstract:
  In this paper, we consider the non-spectral problem for the planar
self-affine measures $\mu_{M,D}$ generated by an expanding integer matrix $M\in
M_2(\mathbb{Z})$ and a finite digit set $D\subset\mathbb{Z}^2$. Let $p\geq2$ be
a positive integer, $E_p^2:=\frac{1}{p}\{(i,j)^t:0\leq i,j\leq p-1\}$ and
$\mathcal{Z}_{D}^2:=\{x\in[0, 1)^2:\sum_{d\in D}{e^{2\pi i\langle
d,x\rangle}}=0\}$. We show that if $\emptyset\neq\mathcal{Z}_{D}^2\subset
E_p^2\setminus\{0\}$ and $\gcd(\det(M),p)=1$, then there exist at most $p^2$
mutually orthogonal exponential functions in $L^2(\mu_{M,D})$. In particular,
if $p$ is a prime, then the number $p^2$ is the best.


title: Ordered set partitions and the 0-Hecke algebra

abstract:
  Let the symmetric group $\mathfrak{S}_n$ act on the polynomial ring
$\mathbb{Q}[\mathbf{x}_n] = \mathbb{Q}[x_1, \dots, x_n]$ by variable
permutation. The coinvariant algebra is the graded $\mathfrak{S}_n$-module $R_n
:= {\mathbb{Q}[\mathbf{x}_n]} / {I_n}$, where $I_n$ is the ideal in
$\mathbb{Q}[\mathbf{x}_n]$ generated by invariant polynomials with vanishing
constant term. Haglund, Rhoades, and Shimozono introduced a new quotient
$R_{n,k}$ of the polynomial ring $\mathbb{Q}[\mathbf{x}_n]$ depending on two
positive integers $k \leq n$ which reduces to the classical coinvariant algebra
of the symmetric group $\mathfrak{S}_n$ when $k = n$. The quotient $R_{n,k}$
carries the structure of a graded $\mathfrak{S}_n$-module; Haglund et. al.
determine its graded isomorphism type and relate it to the Delta Conjecture in
the theory of Macdonald polynomials. We introduce and study a related quotient
$S_{n,k}$ of $\mathbb{F}[\mathbf{x}_n]$ which carries a graded action of the
0-Hecke algebra $H_n(0)$, where $\mathbb{F}$ is an arbitrary field. We prove
0-Hecke analogs of the results of Haglund, Rhoades, and Shimozono. In the
classical case $k = n$, we recover earlier results of Huang concerning the
0-Hecke action on the coinvariant algebra.


title:
The Fefferman-Stein type inequality for strong maximal operator in the
  heigher dimensions

abstract:
  The Fefferman-Stein type inequality for strong maximal operator is verified
with compositions of some maximal operators in the heigher dimensions. An
elementary proof of the endpoint estimate for the strong maximal operator is
also given.


title:
Plancherel distribution of Satake parameters of Maass cusp forms on
  $GL_3$

abstract:
  We prove an equidistribution result for the Satake parameters of Maass cusp
forms on $GL_3$ with respect to the $p$-adic Plancherel measure by using an
application of the Kuznetsov trace formula. The techniques developed in this
paper deal with the removal of arithmetic weight $L(1,F,Ad)^{-1}$ in the
Kuznetsov trace formula on $GL_3$.


title: Perturbations of continuous-time Markov chains

abstract:
  The equivalence of regularity of a Q-matrix with its bounded perturbations is
proved and a integration by parts formula is established for the associated
Feller minimal transition functions.


title:
Structure Evolutions in Atoms of the Elements Executing Confined
  Interstate Electron Dynamics

abstract:
  The mechanisms of structure evolution do not obey the Bravais crystal systems
in gaseous, semisolid and solid atoms. To execute confined interstate electron
dynamics, atoms under neutral states deal with the conservative forces. Prior
to execute electron dynamics, atoms amalgamate under attained dynamics.
Electrons of the outer rings execute dynamics in the structure evolution of
atoms. In binding atoms, a shape of the binding energy depends on the nature of
electron dynamics. In the atoms of space format, a structure evolves above the
ground surface. In the atoms of grounded format, a structure evolves below the
ground surface. The dimensions of structure depend on the number of electrons
simultaneously executing dynamics in atoms. When three electrons of the outer
ring in an atom execute dynamics, a structure of three-dimensional gets
evolved. When two or four electrons of the outer ring in an atom execute
dynamics, a structure of two-dimensional or four-dimensional gets evolved.
Amalgamated or amalgamating atoms bind to the targeted atom at the points of
their generated energy. When the structure evolves in the space format,
amalgamating atoms bind to the targeted atom in lateral manner but from the
upward side. On the other hand, when the structure evolves in the grounded
format, amalgamating atoms bind to the targeted atom in lateral manner but from
the downward side. Further, when the structure evolves in the surface format,
amalgamating atoms bind to the targeted atom in adjacent manner. In each format
of force, bound atoms of mono layers bind through chemical force and chemical
energy. A chemical reactivity of the involved force and the engaged energy
binds mono layers laterally. The structure evolution discussed here may give
new horizon to material science and chemical science.


title: Status and future prospects for CLFV searches at BESIII

abstract:
  Here we present the latest results of the charged Lepton Flavor Violation
process searches at the BESIII experiment in the decay of $J/\psi$ to $e\mu$,
using $(225.3\pm2.8)\times10^6$ $J/\psi$ events collected with the BESIII
detector at the BEPCII collider. An upper limit on the branching fraction of
$B(J/\psi \rightarrow e\mu)<1.6\times10^{-7}$ (90$\%$ C.L.) is obtained. The
prospects and challenges with the future data are also discussed based on MC
simulation.


title:
Black Lives Matter in Wikipedia: Collaboration and Collective Memory
  around Online Social Movements

abstract:
  Social movements use social computing systems to complement offline
mobilizations, but prior literature has focused almost exclusively on movement
actors' use of social media. In this paper, we analyze participation and
attention to topics connected with the Black Lives Matter movement in the
English language version of Wikipedia between 2014 and 2016. Our results point
to the use of Wikipedia to (1) intensively document and connect historical and
contemporary events, (2) collaboratively migrate activity to support coverage
of new events, and (3) dynamically re-appraise pre-existing knowledge in the
aftermath of new events. These findings reveal patterns of behavior that
complement theories of collective memory and collective action and help explain
how social computing systems can encode and retrieve knowledge about social
movements as they unfold.


title: Witnessing irreducible dimension

abstract:
  The Hilbert space dimension of a quantum system is the most basic quantifier
of its information content. Lower bounds on the dimension can be certified in a
device-independent way, based only on observed statistics. We highlight that
some such "dimension witnesses" capture only the presence of systems of some
dimension, which in a sense is trivial, not the capacity of performing
information processing on them, which is the point of experimental efforts to
control high-dimensional systems. In order to capture this aspect, we introduce
the notion of irreducible dimension of a quantum behaviour. This dimension can
be certified, and we provide a witness for irreducible dimension four.


title: Generalized Topic Modeling

abstract:
  Recently there has been significant activity in developing algorithms with
provable guarantees for topic modeling. In standard topic models, a topic (such
as sports, business, or politics) is viewed as a probability distribution $\vec
a_i$ over words, and a document is generated by first selecting a mixture $\vec
w$ over topics, and then generating words i.i.d. from the associated mixture
$A{\vec w}$. Given a large collection of such documents, the goal is to recover
the topic vectors and then to correctly classify new documents according to
their topic mixture.
  In this work we consider a broad generalization of this framework in which
words are no longer assumed to be drawn i.i.d. and instead a topic is a complex
distribution over sequences of paragraphs. Since one could not hope to even
represent such a distribution in general (even if paragraphs are given using
some natural feature representation), we aim instead to directly learn a
document classifier. That is, we aim to learn a predictor that given a new
document, accurately predicts its topic mixture, without learning the
distributions explicitly. We present several natural conditions under which one
can do this efficiently and discuss issues such as noise tolerance and sample
complexity in this model. More generally, our model can be viewed as a
generalization of the multi-view or co-training setting in machine learning.


title: Learning Identity Mappings with Residual Gates

abstract:
  We propose a new layer design by adding a linear gating mechanism to shortcut
connections. By using a scalar parameter to control each gate, we provide a way
to learn identity mappings by optimizing only one parameter. We build upon the
motivation behind Residual Networks, where a layer is reformulated in order to
make learning identity mappings less problematic to the optimizer. The
augmentation introduces only one extra parameter per layer, and provides easier
optimization by making degeneration into identity mappings simpler. We propose
a new model, the Gated Residual Network, which is the result when augmenting
Residual Networks. Experimental results show that augmenting layers provides
better optimization, increased performance, and more layer independence. We
evaluate our method on MNIST using fully-connected networks, showing empirical
indications that our augmentation facilitates the optimization of deep models,
and that it provides high tolerance to full layer removal: the model retains
over 90% of its performance even after half of its layers have been randomly
removed. We also evaluate our model on CIFAR-10 and CIFAR-100 using Wide Gated
ResNets, achieving 3.65% and 18.27% error, respectively.


title:
Direct observation of the M1 transition between the ground state fine
  structure splitting of W VIII

abstract:
  We present direct observation of the M1 transition between the fine structure
splitting in the 4f13 5s2 5p6 2F ground state of W VIII. The spectroscopic data
of few-times ionized tungsten ions are important for the future ITER
diagnostics, but there is a serious lack of data. The present study is part of
an ongoing effort to solve this lack. Emission from the tungsten ions produced
and trapped in a compact electron beam ion trap is observed with a
Czerny-Turner visible spectrometer. Spectra in the EUV range are also observed
at the same time to help the identification of the previously-unreported
visible lines. The observed wavelength 574.47 pm 0.03 nm (air), which
corresponds to the fine structure splitting of 17402.5 pm 0.9 cm-1, shows
reasonable agreement with the previously reported value 17410 pm 5 cm-1
obtained indirectly through the analysis of EUV spectra [Ryabtsev et al., Atoms
3 (2015) 273].


title: An alternating moment condition for bi-freeness

abstract:
  In this note we demonstrate an equivalent condition for bi-freeness, inspired
by the well-known "vanishing of alternating centred moments" condition from
free probability. We show that all products satisfying a centred condition on
maximal monochromatic \chi-intervals have vanishing moments if and only if the
family of pairs of faces they come from is bi-free, and show that similar
characterisations hold for the amalgamated and conditional settings. In
addition, we construct a bi-free unitary Brownian motion and show that
conjugation by this process asymptotically creates bi-freeness; these
considerations lead to another characterisation of bi-free independence.


title: A family of braneworld wormholes

abstract:
  A wormhole solution is presented on a braneworld scenery, the material source
is given by a perfect fluid on brane that does not violate the energy
conditions. we propose an ansatz for the state equation resulting in a family
of solutions that satisfy necessary conditions over the free parameters of the
solution. The effect of projecting the 5D Weyl tensor components on the brane,
give the conditions to have a wormhole satisfying the NEC, besides
simultaneously guaranteeing the absence of horizons. Furthermore, our model
predicts an astronomical bound for the wormhole throat.


title:
Wave propagation in non-centrosymmetric beam-lattices with lumped
  masses: discrete and micropolar modelling

abstract:
  The in-plane acoustic behavior of non-centrosymmetric lattices having nodes
endowed with mass and gyroscopic inertia and connected by massless ligaments
with asymmetric elastic properties has been analysed through a discrete model
and a continuum micropolar model. In the first case the propagation of harmonic
waves and the dispersion functions have been obtained by the discrete
Floquet-Bloch approach. It is shown that the optical branch departs from a
critical point with vanishing group velocity and for the considered cases this
branch is decreasing for increasing the norm of the wave vector from the long
wave limit. A micropolar continuum model, useful to approximate the discrete
model, has been derived through a continualization method based on a
down-scaling law based on a second-order Taylor expansion of the generalized
macro-displacement field. It is worth noting that the second order elasticity
tensor coupling curvatures and micro-couples turns out to be negative defined
also in the general case of non-centrosymmetric lattice. The eigenvalue problem
governing the harmonic propagation in the micropolar non-centrosymmetric
continuum results in general characterized by a hermitian full matrix that is
exact up to the second order in the wave vector. Examples concerning square and
equilateral triangular lattices and their acoustic properties have been
analysed from both the exact Lagrangian model (within the assumed hypotheses)
and the micropolar approximate model. Finally, in consideration of the negative
definiteness of the second order elastic tensor of the micropolar model, the
loss of strong hyperbolicity of the equation of motion has been investigated.


title:
Dispersive wave propagation in two-dimensional rigid periodic blocky
  materials with elastic interfaces

abstract:
  Dispersive waves in two-dimensional blocky materials with periodic
microstructure made up of equal rigid units having polygonal centro-symmetric
shape with mass and gyroscopic inertia, connected each other through
homogeneous linear interfaces, have been analysed. The acoustic behavior of the
resulting discrete Lagrangian model has been obtained through a Floquet-Bloch
approach. From the resulting eigenproblem derived by the Euler-Lagrange
equations for harmonic wave propagation, two acoustic branches and an optical
branch are obtained in the frequency spectrum. A micropolar continuum model to
approximate the Lagrangian model has been derived based on a second-order
Taylor expansion of the generalized macro-displacement field. The constitutive
equations of the equivalent micropolar continuum have been obtained, with the
peculiarity that the positive definiteness of the second-order symmetric tensor
associated to the curvature vector is not guaranteed and depends both on the
ratio between the local tangent and normal stiffness and on the block shape.
The same results has been obtained through an extended Hamiltonian derivation
of the equations of motion for the equivalent continuum that is related to the
Hill-Mandel macro homogeneity condition. Moreover, it is shown that the
hermitian matrix governing the eigenproblem of harmonic wave propagation in the
micropolar model is exact up to the second order in the norm of the wave vector
with respect to the same matrix from the discrete model. To appreciate the
acoustic behavior of some relevant blocky materials and to understand the
reliability and the validity limits of the micropolar continuum model, some
blocky patterns have been analysed: rhombic and hexagonal assemblages and
running bond masonry.


title:
Estimation of Mass of Compact Object in H 1743-322 from 2010 and 2011
  Outbursts using TCAF Solution and Spectral Index - QPO Frequency Correlation

abstract:
  The well known black hole candidate H~1743-322 exhibited temporal and
spectral variabilities during several outbursts. Daily variation of the
accretion rates and the flow geometry change on a daily basis during each of
the outbursts could be understood very well using the recent implementation of
two component advective flow (TCAF) solution of the viscous transonic flow
equations as an additive table model in XSPEC. This has dramatically improved
our understanding about the accretion flow dynamics. Most interestingly, the
solution allows to treat mass of the black hole candidate as a free parameter
and there mass could be estimated from spectral fits. In this paper, we fit the
data of two successive outbursts of H~1743-322 in 2010 and 2011 and studied
evolutions of accretion flow parameters, such as, two component (Keplerian and
sub-Keplerian) accretion rates, shock location (i.e., size of the Compton
cloud), etc. We assume that the model Normalization remains the same accross
the states in both these outbursts. We use this to estimate mass of the black
hole and found that it comes out in the range of $9.25-12.86 M_\odot$. For the
sake of comparison, we also estimated mass using Photon index vs. QPO frequency
correlation method which turns out to be $11.65 \pm 0.67 M_\odot$ using GRO
J1655-40 as reference source. Combining these two estimates, the most probable
mass of the compact object becomes $11.21^{+1.65}_{-1.96} M_\odot$.


title: A normality criterion corresponding to the defect relations

abstract:
  Let ${\cal F}$ be a family of meromorphic functions on a domain $D$. We
present a quite general sufficient condition for ${\cal F}$ to be a normal
family. This criterion contains many known results as special cases. The
overall idea is that certain comparatively weak conditions on ${\cal F}$
locally lead to somewhat stronger conditions, which in turn lead to even
stronger conditions on the limit function $g$ in the famous Zalcman Lemma.
Ultimately, the defect relations for $g$ force normality of ${\cal F}$.


title: Semantic Noise Modeling for Better Representation Learning

abstract:
  Latent representation learned from multi-layered neural networks via
hierarchical feature abstraction enables recent success of deep learning. Under
the deep learning framework, generalization performance highly depends on the
learned latent representation which is obtained from an appropriate training
scenario with a task-specific objective on a designed network model. In this
work, we propose a novel latent space modeling method to learn better latent
representation. We designed a neural network model based on the assumption that
good base representation can be attained by maximizing the total correlation
between the input, latent, and output variables. From the base model, we
introduce a semantic noise modeling method which enables class-conditional
perturbation on latent space to enhance the representational power of learned
latent feature. During training, latent vector representation can be
stochastically perturbed by a modeled class-conditional additive noise while
maintaining its original semantic feature. It implicitly brings the effect of
semantic augmentation on the latent space. The proposed model can be easily
learned by back-propagation with common gradient-based optimization algorithms.
Experimental results show that the proposed method helps to achieve performance
benefits against various previous approaches. We also provide the empirical
analyses for the proposed class-conditional perturbation process including
t-SNE visualization.


title:
Escape and Trapping of Low-Frequency Gravitationally Lensed Rays by
  Compact Objects within Plasma

abstract:
  We consider the gravitational lensing of rays emitted by a compact object
(CO) within a distribution of plasma with power-law density $\propto r^{-h}$.
For the simplest case of a cloud of spherically symmetric cold non-magnetized
plasma, the diverging effect of the plasma and the converging effect of
gravitational lensing compete with one another. When $h<2$, the plasma effect
dominates over the vacuum Schwarzschild curvature, potentially shifting the
radius of the unstable circular photon orbit outside the surface of the CO.
When this occurs, we define two relatively narrow radio-frequency bands in
which plasma effects are particularly significant. Rays in the escape window
have $\omega_{0} < \omega \leq \omega_{+}$ and are free to propagate to
infinity from the CO surface. To a distant observer, the visible portion of the
CO surface appears to shrink as the observed frequency is reduced, and vanishes
entirely at $\omega_{0}$, in excess of the plasma frequency at the CO surface.
We define the anomalous propagation window for frequencies $\omega_{-}< \omega
\leq \omega_{0}$. Rays emitted from the CO surface within this frequency range
are dominated by optical effects from the plasma and curve back to the surface
of the CO, effectively cloaking the star from distant observers. We conclude
with a study of neutron star (NS) compactness ratios for a variety of nuclear
matter equations of state (EoS). For $h=1$, NSs generated from stiff EoS should
display significant frequency dependence in the EW, and lower values of $h$
with softer EoS can also show these effects.


title: Fast property testing and metrics for permutations

abstract:
  The goal of property testing is to quickly distinguish between objects which
satisfy a property and objects that are $\epsilon$-far from satisfying the
property. There are now several general results in this area which show that
natural properties of combinatorial objects can be tested with "constant" query
complexity, depending only on $\epsilon$ and the property, and not on the size
of the object being tested. The upper bound on the query complexity coming from
the proof techniques are often enormous and impractical. It remains a major
open problem if better bounds hold.
  Maybe surprisingly, for testing with respect to the rectangular distance, we
prove there is a universal (not depending on the property), polynomial in
$1/\epsilon$ query complexity bound for two-sided testing hereditary properties
of sufficiently large permutations. We further give a nearly linear bound with
respect to a closely related metric which also depends on the smallest
forbidden subpermutation for the property. Finally, we show that several
different permutation metrics of interest are related to the rectangular
distance, yielding similar results for testing with respect to these metrics.


title:
UGC 3672: An unusual merging triplet of gas-rich galaxies in the
  Lynx-Cancer void

abstract:
  We present HI 21cm and optical observations of UGC 3672 which is located near
the centre of the nearby Lynx-Cancer void. We find that UGC 3672 consists of an
approximately linearly aligned triplet of gas rich dwarfs with large scale
velocity continuity along the triplet axis. The faintest component of the
triplet is extremely gas-rich (MHI/LB ~ 17) and also extremely metal deficient
(12+log(O/H) ~ 7.0). The metallicity of this dwarf is close to the 'floor'
observed in star forming galaxies. Low resolution HI images show that the
galaxy triplet is located inside a common HI envelope, with fairly regular,
disk like kinematics. At high angular resolution however, the gas is found to
be confined to several filamentary tidal tails and bridges. The linear
alignment of the galaxies, along with the velocity continuity that we observe,
is consistent with the galaxies lying along a filament. We argue that the
location of this highly unusual system in an extremely low density environment
is not a coincidence, but is a consequence of structure formation proceeding
more slowly and also probing smaller scales than in regions with average
density. Our observations also indicate that wet mergers of galaxies flowing
along filaments is a possible pathway for the formation of gas rich disks. The
UGC 3672 system provides an interesting opportunity to study the kind of
interactions typical between high redshift extremely gas rich unevolved small
systems that lie at base of the hierarchical galaxy formation model.


title:
Could freely available articles reduce faculty reliance on library for
  access? An analysis of items cited by faculty from Singapore Management
  University

abstract:
  Various studies have attempted to assess the amount of free full text
available on the web and recent work have suggested that we are close to the
50% mark for freely available articles (Archambault et al. 2013; Bjork et al.
2010; Jamali and Nabavi 2015). It is natural to wonder if this might reduce
researchers' reliance on library subscriptions for access. To do so, we need to
determine not just what papers researchers are citing to that are free today,
but to estimate if the papers they were citing were freely available at the
time they were citing it. We attempt to do so for a sample of citations made by
researchers in the Singapore Management University in the field of Economics.


title:
Diffuse radio emission in MACS J0025.4$-$1222: the effect of a major
  merger on bulk separation of ICM components

abstract:
  Mergers of galaxy clusters are among the most energetic events in the
Universe. These events have significant impact on the intra-cluster medium,
depositing vast amounts of energy - often in the form of shocks - as well as
heavily influencing the properties of the constituent galaxy population. Many
clusters have been shown to host large-scale diffuse radio emission, known
variously as radio haloes and relics. These sources arise as a result of
electron (re-)acceleration in cluster-scale magnetic fields, although the
processes by which this occurs are still poorly understood. We present new,
deep radio observations of the high-redshift galaxy cluster MACS
J0025.4$-$1222, taken with the GMRT at 325 MHz, as well as new analysis of all
archival $Chandra$ X-ray observations. We aim to investigate the potential of
diffuse radio emission and categorise the radio population of this cluster,
which has only been covered previously by shallow radio surveys. We produce
low-resolution maps of MACS J0025.4$-$1222 through a combination of uv-tapering
and subtracting the compact source population. Radial surface brightness and
mass profiles are derived from the $Chandra$ data. We also derive a 2D map of
the ICM temperature. For the first time, two sources of diffuse radio emission
are detected in MACS J0025.4$-$1222, on linear scales of several hundred kpc.
Given the redshift of the cluster and the assumed cosmology, these sources
appear to be consistent with established trends in power scaling relations for
radio relics. The X-ray temperature map presents evidence of an asymmetric
temperature profile and tentative identification of a temperature jump
associated with one relic. We classify the pair of diffuse radio sources in
this cluster as a pair of radio relics, given their consistency with scaling
relations, location toward the cluster outskirts, and the available X-ray data.


title: Evaluation of Log-tangent Integrals by series involving $\zeta(2n+1)$

abstract:
  In this note, we show that the values of integrals of the log-tangent
function with respect to any square-integrable function on $\left[0 ,
\frac{\pi}{2} \right]$ may be determined by a finite or infinite sum involving
the Riemann Zeta-function at odd positive integers.


title:
Action-angle variables for geodesic motions in Sasaki-Einstein spaces
  $Y^{p,q}$

abstract:
  We use the action-angle variables to describe the geodesic motions in the
$5$-dimensional Sasaki-Einstein spaces $Y^{p,q}$. This formulation allows us to
study thoroughly the complete integrability of the system. We find that the
Hamiltonian involves a reduced number of action variables. Therefore one of the
fundamental frequency is zero indicating a chaotic behavior when the system is
perturbed.


title: A Communication-Efficient Parallel Algorithm for Decision Tree

abstract:
  Decision tree (and its extensions such as Gradient Boosting Decision Trees
and Random Forest) is a widely used machine learning algorithm, due to its
practical effectiveness and model interpretability. With the emergence of big
data, there is an increasing need to parallelize the training process of
decision tree. However, most existing attempts along this line suffer from high
communication costs. In this paper, we propose a new algorithm, called
\emph{Parallel Voting Decision Tree (PV-Tree)}, to tackle this challenge. After
partitioning the training data onto a number of (e.g., $M$) machines, this
algorithm performs both local voting and global voting in each iteration. For
local voting, the top-$k$ attributes are selected from each machine according
to its local data. Then, globally top-$2k$ attributes are determined by a
majority voting among these local candidates. Finally, the full-grained
histograms of the globally top-$2k$ attributes are collected from local
machines in order to identify the best (most informative) attribute and its
split point. PV-Tree can achieve a very low communication cost (independent of
the total number of attributes) and thus can scale out very well. Furthermore,
theoretical analysis shows that this algorithm can learn a near optimal
decision tree, since it can find the best attribute with a large probability.
Our experiments on real-world datasets show that PV-Tree significantly
outperforms the existing parallel decision tree algorithms in the trade-off
between accuracy and efficiency.


title: Multiquark Hadrons

abstract:
  A number of candidate multiquark hadrons, i.e., particle resonances with
substructures that are more complex than the quark-antiquark mesons and
three-quark baryons that are prescribed in the textbooks, have recently been
observed. In this talk I present: some recent preliminary BESIII results on the
near-threshold behavior of sigma(e+e- --> Lambda Lambda-bar) that may or may
not be related to multiquark mesons in the light- and strange-quark sectors;
results from Belle and LHCb on the electrically charged, charmoniumlike
Z(4430)^+ --> pi^+ psi ' resonance that necessarily has a four-quark
substructure; and the recent LHCb discovery of the P_c(4380) and P_c(4450)
hidden-charm resonances seen as a complex structure in the J/psi p invariant
mass distribution for Lambda_b --> K^-J/psi p decays and necessarily have a
five-quark substructure and are, therefore, prominent candidates for pentaquark
baryons.


title:
Topological Interference Management: Linear Cooperation is not useful
  for Wyner's Networks

abstract:
  In this work, we study the value of cooperative transmission in wireless
networks if no channel state information is available at the transmitters (no
CSIT). Our focus is on large locally connected networks, where each transmitter
is connected to the receiver that has the same index as well as L succeeding
receivers. The cases of L=1 and L=2 represent Wyner's asymmetric and symmetric
network models, respectively. The considered rate criterion is the per user
Degrees of Freedom (puDoF) as the number of transmitter-receiver pairs goes to
infinity. For the case when L=1, it was shown in previous work that linear
cooperation schemes do not increases the puDoF value, and that the optimal
scheme relies on assigning each message to a single transmitter and using
orthogonal access (TDMA). Here, we extend this conclusion to the case where
L=2, by proving optimality of TDMA in this case as well. We conclude by
discussing whether increasing the value of L can create a value for linear
cooperation schemes from a DoF perspective.


title: 3.5-Year Monitoring of 225 GHz Opacity at the Summit of Greenland

abstract:
  We present the 3.5-yr monitoring results of 225 GHz opacity at the summit of
the Greenland ice sheet (Greenland Summit Camp) at an altitude of 3200 m using
a tipping radiometer. We chose this site as our submillimeter telescope
(Greenland Telescope; GLT) site, because its location offers favorable
baselines to existing submillimeter telescopes for global-scale VLBI. The site
shows a clear seasonal variation with the average opacity lower by a factor of
two during winter. For the winter quartiles of 25% and 50%, the Greenland site
is about 10%-30% worse than the ALMA or the South Pole sites. Estimated
atmospheric transmission spectra in winter season are similar to the ALMA site
at lower frequencies (<450 GHz), which are transparent enough to perform
astronomical observations almost all of the winter time with opacities <0.5,
but 10%-25% higher opacities at higher frequencies (>450 GHz) than those at the
ALMA site. This is due to the lower altitude of the Greenland site.
Nevertheless, half of the winter time at the Greenland site can be used for
astronomical observations at frequencies between 450 GHz and 1000 GHz with
opacities <1.2, and 10% of the time show >10% transmittance in the THz (1035
GHz, 1350 GHz, and 1500 GHz) windows. One major advantage of the Greenland site
in winter is that there is no diurnal variation due to the polar night
condition, and therefore the durations of low-opacity conditions are
significantly longer than at the ALMA site. Opacities lower than 0.05 or 0.04
can continue for more than 100 hours. Such long stable opacity conditions do
not occur as often even at the South Pole; it happens only for the opacity
lower than 0.05. Since the opacity variation is directly related to the sky
temperature (background) variation, the Greenland site is suitable for
astronomical observations that need unusually stable sky background.


title: Optimal portfolio selection under vanishing fixed transaction costs

abstract:
  In this paper, asymptotic results in a long-term growth rate portfolio
optimization model under both fixed and proportional transaction costs are
obtained. More precisely, the convergence of the model when the fixed costs
tend to zero is investigated. A suitable limit model with purely proportional
costs is introduced and an optimal strategy is shown to consist of keeping the
risky fraction process in a unique interval $[A,B]\subseteq\,]0,1[$ with
minimal effort. Furthermore, the convergence of optimal boundaries, asymptotic
growth rates, and optimal risky fraction processes is rigorously proved. The
results are based on an in-depth analysis of the convergence of the solutions
to the corresponding HJB-equations.


title:
A new coupled computational method in conjunction with three-dimensional
  finite volume schemes for nonlinear coupled constitutive relations

abstract:
  Non-equilibrium effects play a vital role in high-speed and rarefied gas
flows and the accurate simulation of these flow regimes are far beyond the
capability of near-local-equilibrium Navier-Stokes-Fourier equations. Eu
proposed generalized hydrodynamic equations which are consistent with the laws
of irreversible thermodynamics to solve this problem. Based on Eu's generalized
hydrodynamics equations, a computational model, namely the nonlinear coupled
constitutive relations(NCCR),was developed by R.S.Myong and applied
successfully to one-dimensional shock wave structure and two-dimensional
rarefied flows. In this paper, finite volume schemes, including LU-SGS time
advance scheme, MUSCL interpolation and AUSMPW+ scheme, are fistly adopted to
investigate NCCR model's validity and potential in three-dimensional complex
hypersonic rarefied gas flows. Moreover, in order to solve the computational
stability problems in 3D complex flows,a modified solution is developed for the
NCCR model. Finally, the modified solution is tested for a slip complex flow
over a 3D hollow cylinder-flare configuration. The numerical results show that
the NCCR model by the modified solution yields good solutions in better
agreement with the DSMC results and experimential data than NSF equations, and
imply NCCR model's great potential capability in further application.


title:
Comment on "Generalized Shannon--Khinchin axioms and uniqueness theorem
  for pseudo-additive entropies" [Physica A 411 (2014) 138]

abstract:
  Recently in [Physica A 411 (2014) 138] Ili\'{c} and Stankovi\'{c} have
suggested that there may be problem for the class of hybrid entropies
introduced in [P.~Jizba and T.~Arimitsu, Physica A 340 (2004) 110]. In this
Comment we point out that the problem can be traced down to the $q$-additive
entropic chain rule and to a peculiar behavior of the DeFinetti--Kolmogorov
relation for escort distributions. However, despite this, one can still safely
use the proposed hybrid entropies in most of the statistical-thermodynamics
considerations.


title: Nonlinear infrared spectroscopy free from spectral selection

abstract:
  Infrared (IR) spectroscopy is an indispensable tool for many practical
applications including material analysis and sensing. Existing IR spectroscopy
techniques face challenges related to the inferior performance and the high
cost of IR-grade components. Here, we develop a new method, which allows
studying properties of materials in the IR range using only visible light
optics and detectors. It is based on the nonlinear interference of entangled
photons, generated via Spontaneous Parametric Down Conversion (SPDC). In our
interferometer, the phase of the signal photon in the visible range depends on
the phase of an entangled IR photon. When the IR photon is traveling through
the media, its properties can be found from observations of the visible photon.
We directly acquire the SPDC signal with a visible range CCD camera and use a
numerical algorithm to infer the absorption coefficient and the refraction
index of the sample in the IR range. Our method does not require the use of a
spectrometer and a slit, thus it allows achieving higher signal-to-noise ratio
than the earlier developed method.


title: On defects of characters and decomposition numbers

abstract:
  We propose upper bounds for the number of modular constituents of the
restriction modulo $p$ of a complex irreducible character of a finite group,
and for its decomposition numbers, in certain cases.


title: Naive Diversification Preferences and their Representation

abstract:
  A widely applied diversification paradigm is the naive diversification choice
heuristic. It stipulates that an economic agent allocates equal decision
weights to given choice alternatives independent of their individual
characteristics. This article provides mathematically and economically sound
choice theoretic foundations for the naive approach to diversification. We
axiomatize naive diversification by defining it as a preference for equality
over inequality and derive its relationship to the classical diversification
paradigm. In particular, we show that (i) the notion of permutation invariance
lies at the core of naive diversification and that an economic agent is a naive
diversifier if and only if his preferences are convex and permutation
invariant; (ii) Schur-concave utility functions capture the idea of being
inequality averse on top of being risk averse; and (iii) the transformations,
which rebalance unequal decision weights to equality, are characterized in
terms of their implied turnover.


title: Integrating a Model of Analytical Quality Assurance into the V-Modell XT

abstract:
  Economic models of quality assurance can be an important tool for decision
makers in software development projects. They enable to base quality assurance
planning on economical factors of the product and the used defect-detection
techniques. A variety of such models has been proposed but many are too
abstract to be used in practice. Furthermore, even the more concrete models
lack an integration with existing software development process models to
increase their applicability. This paper describes an integration of a thorough
stochastic model of the economics of analytical quality assurance with the
systems development process model V-Modell XT. The integration is done in a
modular way by providing a new process module - a concept directly available in
the V-Modell XT for extension purposes - related to analytical quality
assurance. In particular, we describe the work products, roles, and activities
defined in our new process module and their effects on existing V-Modell XT
elements.


title: Managing Quality Requirements Using Activity-Based Quality Models

abstract:
  Managing requirements on quality aspects is an important issue in the
development of software systems. Difficulties arise from expressing them
appropriately what in turn results from the difficulty of the concept of
quality itself. Building and using quality models is an approach to handle the
complexity of software quality. A novel kind of quality models uses the
activities performed on and with the software as an explicit dimension. These
quality models are a well-suited basis for managing quality requirements from
elicitation over refinement to assurance. The paper proposes such an approach
and shows its applicability in an automotive case study.


title:
Sharp general and metric bounds for the star discrepancy of perturbed
  Halton--Kronecker sequences

abstract:
  We consider the star discrepancy of two-dimensional sequences made up as a
hybrid between a Kronecker sequence and a perturbed Halton sequence in base 2,
where the perturbation is achieved by a digital-sequence construction in the
sense of Niederreiter whose generating matrix contains a periodic perturbing
sequence of a given period length. Under the assumption that the Kronecker
sequence involves a parameter with bounded continued fraction coefficients
sharp discrepancy estimates are obtained. Furthermore, we study the problem
from a metric point of view as well. Finally, we also present sharp general and
tight metric bounds for certain lacunary trigonometric products which appear to
be strongly related to these problems.


title: Dynamical Space-Time and Gravitational Waves

abstract:
  According to General Relativity gravity is the result of the interaction
between matter and space-time geometry. In this interaction space-time geometry
itself is dynamical: it can store and transport energy and momentum in the form
of gravitational waves. We give an introductory account of this phenomenon and
discuss how the observation of gravitational waves may open up a fundamentally
new window on the universe.


title: The Research Data Alliance

abstract:
  The Research Data Alliance (RDA, https://www.rd-alliance.org/) aims at
enabling research data sharing without barriers. It was founded in March 2013
by the Australian Government, the European Commission, and the USA NSF and
NIST. It is a bottom-up organisation which after 2 years and a half of
existence gathers around 3,000 members from 100 different countries. Work in
RDA is organised in a bottom-up way, through Working Groups and Interest Groups
proposed by the community. These Groups can deal with any aspect of research
data sharing, which means a huge diversity in the activities. Some scientific
communities use the RDA as a neutral place to hold the discussions about their
disciplinary interoperability framework. Astronomy has the IVOA and the FITS
Committee for that purpose, and the ADASS Colloquia to deal with astronomical
data systems. But many RDA topics are of interest for us, for instance data
citation, including citation of dynamic data bases and data repositories, or
certification of data repositories. Also lessons learnt in building the IVOA
and data sharing in astronomy are injected in the discussion of RDA
organisation and procedures. The RDA is a unique platform to meet data
practitioners from many countries, disciplines and profiles, to grasp ideas to
improve our data practices, to identify topics of common interest and to raise
interesting subjects for discussion involving specialists from many disciplines
and countries by proposing new Interest and Working Groups.


title: Tighter Hard Instances for PPSZ

abstract:
  We construct uniquely satisfiable $k$-CNF formulas that are hard for the
algorithm PPSZ. Firstly, we construct graph-instances on which "weak PPSZ" has
savings of at most $(2 + \epsilon) / k$; the saving of an algorithm on an input
formula with $n$ variables is the largest $\gamma$ such that the algorithm
succeeds (i.e. finds a satisfying assignment) with probability at least $2^{ -
(1 - \gamma) n}$. Since PPSZ (both weak and strong) is known to have savings of
at least $\frac{\pi^2 + o(1)}{6k}$, this is optimal up to the constant factor.
In particular, for $k=3$, our upper bound is $2^{0.333\dots n}$, which is
fairly close to the lower bound $2^{0.386\dots n}$ of Hertli [SIAM J.
Comput.'14]. We also construct instances based on linear systems over
$\mathbb{F}_2$ for which strong PPSZ has savings of at most
$O\left(\frac{\log(k)}{k}\right)$. This is only a $\log(k)$ factor away from
the optimal bound. Our constructions improve previous savings upper bound of
$O\left(\frac{\log^2(k)}{k}\right)$ due to Chen et al. [SODA'13].


title: The Braking Index of a Radio-quiet Gamma-ray Pulsar

abstract:
  We report the discovery and timing measurements of PSR J1208-6238, a young
and highly magnetized gamma-ray pulsar, with a spin period of 440 ms. The
pulsar was discovered in gamma-ray photon data from the Fermi Large Area
Telescope (LAT) during a blind-search survey of unidentified LAT sources,
running on the distributed volunteer computing system Einstein@Home. No radio
pulsations were detected in dedicated follow-up searches with the Parkes radio
telescope, with a flux density upper limit at 1369 MHz of 30 $\mu$Jy. By timing
this pulsar's gamma-ray pulsations, we measure its braking index over five
years of LAT observations to be $n = 2.598 \pm 0.001 \pm 0.1$, where the first
uncertainty is statistical and the second estimates the bias due to timing
noise. Assuming its braking index has been similar since birth, the pulsar has
an estimated age of around 2,700 yr, making it the youngest pulsar to be found
in a blind search of gamma-ray data and the youngest known radio-quiet
gamma-ray pulsar. Despite its young age the pulsar is not associated with any
known supernova remnant or pulsar wind nebula. The pulsar's inferred dipolar
surface magnetic field strength is $3.8 \times 10^{13}$ G, almost 90% of the
quantum-critical level. We investigate some potential physical causes of the
braking index deviating from the simple dipole model but find that LAT data
covering a longer time interval will be necessary to distinguish between these.


title:
Structure-Related Optical Fingerprints in the Absorption Spectra of
  Colloidal Quantum Dots: Random Alloy vs. Core/Shell Systems

abstract:
  We argue that the experimentally easily accessible optical absorption
spectrum can often be used to distinguish between a random alloy phase and a
stoichiometrically equivalent core/shell realization of ensembles of
monodisperse colloidal semiconductor quantum dots without the need for more
advanced structural characterization tools. Our proof-of-concept is performed
by conceptually straightforward exact-disorder tight-binding calculations. The
underlying stochastical tight-binding scheme only parametrizes bulk band
structure properties and does not employ additional free parameters to
calculate the optical absorption spectrum, which is an easily accessible
experimental property. The method is applied to selected realizations of type-I
Cd(Se,S) and type-II (Zn,Cd)(Se,S) alloyed quantum dots with an underlying
zincblende crystal structure and the corresponding core/shell counterparts.