title: Radio number of trees

abstract:
  A radio labeling of a graph $G$ is a mapping $f: V(G) \rightarrow \{0, 1, 2,
\ldots\}$ such that $|f(u)-f(v)|\geq d + 1 - d(u,v)$ for every pair of distinct
vertices $u, v$ of $G$, where $d$ is the diameter of $G$ and $d(u,v)$ the
distance between $u$ and $v$ in $G$. The radio number of $G$ is the smallest
integer $k$ such that $G$ has a radio labeling $f$ with $\max\{f(v) : v \in
V(G)\} = k$. We give a necessary and sufficient condition for a lower bound on
the radio number of trees to be achieved, two other sufficient conditions for
the same bound to be achieved by a tree, and an upper bound on the radio number
of trees. Using these, we determine the radio number for three families of
trees.


title:
The Applied Pi Calculus: Mobile Values, New Names, and Secure
  Communication

abstract:
  We study the interaction of the programming construct "new", which generates
statically scoped names, with communication via messages on channels. This
interaction is crucial in security protocols, which are the main motivating
examples for our work, it also appears in other programming-language contexts.
  We define the applied pi calculus, a simple, general extension of the pi
calculus in which values can be formed from names via the application of
built-in functions, subject to equations, and be sent as messages. (In
contrast, the pure pi calculus lacks built-in functions, its only messages are
atomic names.) We develop semantics and proof techniques for this extended
language and apply them in reasoning about security protocols.
  This paper essentially subsumes the conference paper that introduced the
applied pi calculus in 2001. It fills gaps, incorporates improvements, and
further explains and studies the applied pi calculus. Since 2001, the applied
pi calculus has been the basis for much further work, described in many
research publications and sometimes embodied in useful software, such as the
tool ProVerif, which relies on the applied pi calculus to support the
specification and automatic analysis of security protocols. Although this paper
does not aim to be a complete review of the subject, it benefits from that
further work and provides better foundations for some of it. In particular, the
applied pi calculus has evolved through its implementation in ProVerif, and the
present definition reflects that evolution.


title: Mean and Minimum of Independent Random Variables

abstract:
  We show that any pair $X, Y$ of independent, non-compactly supported random
variables on $[0,\infty)$ satisfies $\liminf_{m\to\infty} \mathbb{P}(\min(X,Y)
>m \,| \,X+Y> 2m) =0$. We conjecture multi-variate and weighted generalizations
of this result, and prove them under the additional assumption that the random
variables are identically distributed.


title: Role of correlations on spin-polarized neutron matter

abstract:
  Using the Hellmann--Feynman theorem we analyze the contribution of the
different terms of the nucleon-nucleon interaction to the spin symmetry energy
of neutron matter. The analysis is performed within the microscopic
Brueckner--Hartree--Fock approach using the Argonne V18 realistic potential
plus the Urbana IX three-body force. The main contribution to the spin-symmetry
energy of neutron matter comes from the S=0 channel, acting only in the
non-polarized neutron matter, in particular the $^1S_0$ and the $^1D_2$ partial
waves. The importance of correlations in spin-polarized neutron matter is
estimated by evaluating the kinetic energy difference between the correlated
system and the underlying Fermi sea.


title: The squaring operartion and the Singer algebraic transfer

abstract:
  Let $P_k$ be the graded polynomial algebra $\mathbb F_2[x_1,x_2,\ldots
,x_k]$, with the degree of each $x_i$ being 1, regarded as a module over the
mod-2 Steenrod algebra $\mathcal A$, and let $GL_k$ be the general linear group
over the prime field $\mathbb F_2$ which acts regularly on $P_k$. We study the
algebraic transfer constructed by Singer using the technique of the hit
problem. This transfer is a homomorphism from the homology of the mod-2
Steenrod algebra, $\text{Tor}^{\mathcal A}_{k,k+n} (\mathbb F_2,\mathbb F_2)$,
to the subspace of $\mathbb F_2{\otimes}_{\mathcal A}P_k$ consisting of all the
$GL_k$-invariant classes of degree $n$. In this paper, we extend a result of
Hung on the relation between the Singer algebraic transfer and the squaring
operation on the cohomology of the Steenrod algebra. Using this result, we show
that Singer's conjecture for the algebraic transfer is true in the case $k=5$
and the degree $5(2^{s} -1)$ with $s$ an arbitrary positive integer.


title:
$\phi^3$ theory with $F_4$ flavor symmetry in $6-2\epsilon$ dimensions:
  3-loop renormalization and conformal bootstrap

abstract:
  We consider $\phi^3$ theory in $6-2\epsilon$ with $F_4$ global symmetry. The
beta function is calculated up to 3 loops, and a stable unitary IR fixed point
is observed. The anomalous dimensions of operators quadratic or cubic in $\phi$
are also computed. We then employ conformal bootstrap technique to study the
fixed point predicted from the perturbative approach. For each putative scaling
dimension of $\phi$ ($\Delta_{\phi})$, we obtain the corresponding upper bound
on the scaling dimension of the second lowest scalar primary in the ${\mathbf
26}$ representation $(\Delta^{\rm 2nd}_{{\mathbf 26}})$ which appears in the
OPE of $\phi\times\phi$. In $D=5.95$, we observe a sharp peak on the upper
bound curve located at $\Delta_{\phi}$ equal to the value predicted by the
3-loop computation. In $D=5$, we observe a weak kink on the upper bound curve
at $(\Delta_{\phi},\Delta^{\rm 2nd}_{{\mathbf 26}})$=$(1.6,4)$.


title: A regular analogue of the Smilansky model: spectral properties

abstract:
  We analyze spectral properties of the operator $H=\frac{\partial^2}{\partial
x^2} -\frac{\partial^2}{\partial y^2} +\omega^2y^2-\lambda y^2V(x y)$ in
$L^2(\mathbb{R}^2)$, where $\omega\ne 0$ and $V\ge 0$ is a compactly supported
and sufficiently regular potential. It is known that the spectrum of $H$
depends on the one-dimensional Schr\"odinger operator
$L=-\frac{\mathrm{d}^2}{\mathrm{d}x^2}+\omega^2-\lambda V(x)$ and it changes
substantially as $\inf\sigma(L)$ switches sign. We prove that in the critical
case, $\inf\sigma(L)=0$, the spectrum of $H$ is purely essential and covers the
interval $[0,\infty)$. In the subcritical case, $\inf\sigma(L)>0$, the
essential spectrum starts from $\omega$ and there is a non-void discrete
spectrum in the interval $[0,\omega)$. We also derive a bound on the
corresponding eigenvalue moments.


title: Hermite-Halphen-Bloch solution of two-gap Lam\'e equation

abstract:
  We construct the Hermite--Halphen--Bloch solution for the two-gap ($n=2$)
Lam\'e equation of Jacobian form and give closed formulae to calculate the
energy band dispersion relation.

categories: math-ph cond-mat.stat-mech hep-th math.MP nlin.SI


title:
Induced ferromagnetic moment at the interface between epitaxial
  SrRuO$_3$ film and Sr$_2$RuO$_4$ single crystal

abstract:
  SrRuO$_3$ (SRO113) is an important material for device physics particularly
as one of the best metallic oxide electrodes for ferroelectric devices. This
oxide has moderate electron correlations with novel properties including
ferromagnetic ordering, which can be utilized in future to spintronics and
superconducting spintronics devices. Recently, we observed strongly enhanced
magnetization of SRO113 thin films grown on single crystals of the spin-triplet
superconductor Sr$_2$RuO$_4$ (SRO214). To clarify the origin of such an
enhancement, we conducted systematic investigations of magnetic properties of
SRO113 films deposited on a variety of oxide substrates. We carefully
subtracted the substrate contributions and found that the enhanced 2
magnetization occurs only for SRO113/SRO214 films. We further found that
neither strain nor metallicity of the substrate plays any significant roles in
the enhancement. The X-ray magnetic circular dichroism reveals that the
substrate-induced strain does not switch the Ru4+ state from the low-spin to
high-spin states. The film-thickness dependence of the magnetization of
SRO113/SRO214 films strongly suggest that the additional magnetization arises
due to the induction of magnetic moment into the SRO214 substrate over 20-nm
depth. Our results imply new magnetic functionality that can trigger studies
searching for yet unknown physical phenomena in magnetic ruthenates.


title:
Explicit Solutions for Optimal Stopping of Linear Diffusion and its
  Maximum

abstract:
  We provide, in a general setting, explicit solutions for optimal stopping
problems that involve diffusion process and its running maximum. Our approach
is to use the excursion theory for Levy processes. Since general diffusions
are, in particular, not of independent increments, we use an appropriate
measure change to make the process have that property. Then we rewrite the
original two-dimensional problem as an infinite number of one-dimensional ones
and complete the solution. We show general solution methods with explicit value
functions and corresponding optimal strategies, illustrating them by some
examples.


title: Arithmetic Chern-Simons Theory II

abstract:
  We apply ideas of Dijkgraaf and Witten on three-dimensional topological
quantum field theory to arithmetic curves, that is, the spectra of rings of
integers in algebraic number fields. In the first three sections, we define
classical Chern-Simons actions on spaces of Galois representations. In the
subsequent sections, we give formulas for computation in a small class of cases
and point towards some arithmetic applications.


title: Algorithmic Aspects of Regular Graph Covers

abstract:
  A graph $G$ covers a graph $H$ if there exists a locally bijective
homomorphism from $G$ to $H$. We deal with regular covers where this
homomorphism is prescribed by the action of a semiregular subgroup of
$\textrm{Aut}(G)$. We study computational aspects of regular covers that have
not been addressed before. The decision problem RegularCover asks for given
graphs $G$ and $H$ whether $G$ regularly covers $H$. When $|H|=1$, this problem
becomes Cayley graph recognition for which the complexity is still unresolved.
Another special case arises for $|G| = |H|$ when it becomes the graph
isomorphism problem.
  Our main result is an involved FPT algorithm solving RegularCover for planar
inputs $G$ in time $O^*(2^{e(H)/2})$ where $e(H)$ denotes the number of edges
of $H$. The algorithm is based on dynamic programming and employs theoretical
results proved in a related structural paper. Further, when $G$ is 3-connected,
$H$ is 2-connected or the ratio $|G|/|H|$ is an odd integer, we can solve the
problem RegularCover in polynomial time. In comparison, B\'ilka et al. (2011)
proved that testing general graph covers is NP-complete for planar inputs $G$
when $H$ is a small fixed graph such as $K_4$ or $K_5$.


title:
Proceedings 9th International Workshop on Computing with Terms and
  Graphs

abstract:
  This volume contains the proceedings of TERMGRAPH 2016, the Ninth
International Workshop on Computing with Terms and Graphs which was held on
April 8, 2016 in Eindhoven, The Netherlands, as a satellite event of the
European Joint Conferences on Theory and Practice of Software (ETAPS 2016).


title:
Geometrically Frustrated Coarsening Dynamics in Spinor Bose-Fermi
  Mixtures

abstract:
  Coarsening dynamics theory has successfully described the equilibration of a
broad class of systems.By studying the relaxation of a periodic array of
microcondensates immersed in a Fermi gas which can mediate long-range spin
interactions to simulate frustrated classical magnets, we show that coarsening
dynamics can be suppressed by geometrical frustration. The system is found to
eventually approach a metastable state which is robust against random field
noise and characterized by finite correlation lengths with the emergence of
topologically stable Z2 vortices. We find universal scaling laws with no
thermal-equilibrium analog that relate the correlation lengths and the number
of vortices to the degree of frustration in the system.


title:
Adaptive Certainty-Equivalence Control With Regulation-Triggered
  Finite-Time Least-Squares Identification, Part I: Design

abstract:
  For general nonlinear control systems we present a novel approach to adaptive
control, which employs a certainty equivalence (indirect) control law and an
identifier with event-triggered updates of the plant parameter estimates, where
the triggers are based on the size of the plant's state and the updates are
conducted using a non-recursive least-squares estimation over certain finite
time intervals, with updates employing delayed measurements of the state. With
a suitable non-restrictive parameter-observability assumption, our adaptive
controller guarantees global stability, regulation of the plant state, and our
identifier achieves parameter convergence, in finite time, even in the absence
of persistent excitation, for all initial conditions other than those where the
initial plant state is zero. The robustness of our event-triggered adaptive
control scheme to vanishing and non-vanishing disturbances is verified in
simulations with the assistance of a dead zone-like modification of the update
law. The major distinctions of our approach from supervisory adaptive schemes
is that our approach is indirect and our triggering is related to the control
objective (the regulation error). The major distinction from the classical
indirect Lyapunov adaptive schemes based on tuning related to the regulation
error is that our approach does not involve a complex redesign of the
controller to compensate for the detrimental effects of rapid tuning on the
transients by incorporating the update law into the control law. Instead, our
approach allows for the first time to use a simple certainty equivalence
adaptive controller for general nonlinear systems. All proofs are given in a
companion paper.


title:
Adaptive Certainty-Equivalence Control With Regulation-Triggered
  Finite-Time Least-Squares Identification, Part II: Analysis

abstract:
  We present the stability analysis for the new regulation-triggered approach
to adaptive control introduced in a companion paper. Due to the fact that the
closed-loop system is hybrid, our proofs have essential differences from the
conventional adaptive control proofs, where the Lyapunov analysis either
encompasses the complete closed-loop state or is done in multiple steps through
comparison or Gronwall-Bellman lemmas. In addition, we present a convenient
algorithm for checking our parameter-observability assumption, which involves
repeated Lie derivatives of appropriate vector fields and can be applied to the
class of nonlinear control systems for which at most one unknown parameter
appears in each differential equation.


title: Physics at a Higgs Factory

abstract:
  I give an overview of the physics potential at possible future $e^+ e^-$
colliders, including the ILC, FCC-ee, and CEPC. The goal is to explain some of
the measurements that can be done in the context of electroweak precision tests
and Higgs couplings, to compare some of the options under consideration, and to
put the measurements in context by summarizing their implications for some new
physics scenarios. This is a writeup of a plenary talk at the Hong Kong
University of Science and Technology Jockey Club Institute for Advanced Study
Program on High Energy Physics Conference, January 18--21, 2016. Some
previously unpublished electroweak precision results for FCC-ee and CEPC are
included.


title:
The imprint of exoplanet formation history on observable present-day
  spectra of hot Jupiters

abstract:
  The composition of a planet's atmosphere is determined by its formation,
evolution, and present-day insolation. A planet's spectrum therefore may hold
clues on its origins. We present a "chain" of models, linking the formation of
a planet to its observable present-day spectrum. The chain links include (1)
the planet's formation and migration, (2) its long-term thermodynamic
evolution, (3) a variety of disk chemistry models, (4) a non-gray atmospheric
model, and (5) a radiometric model to obtain simulated spectroscopic
observations with JWST and ARIEL. In our standard chemistry model the inner
disk is depleted in refractory carbon as in the Solar System and in white
dwarfs polluted by extrasolar planetesimals. Our main findings are: (1)
Envelope enrichment by planetesimal impacts during formation dominates the
final planetary atmospheric composition of hot Jupiters. We investigate two,
under this finding, prototypical formation pathways: a formation inside or
outside the water iceline, called "dry" and "wet" planets, respectively. (2)
Both the "dry" and "wet" planets are oxygen-rich (C/O<1) due to the oxygen-rich
nature of the solid building blocks. The "dry" planet's C/O ratio is <0.2 for
standard carbon depletion, while the "wet" planet has typical C/O values
between 0.1 and 0.5 depending mainly on the clathrate formation efficiency.
Only non-standard disk chemistries without carbon depletion lead to carbon-rich
C/O ratios >1 for the "dry" planet. (3) While we consistently find C/O ratios
<1, they still vary significantly. To link a formation history to a specific
C/O, a better understanding of the disk chemistry is thus needed.


title:
Automated Dynamic Analysis of Ransomware: Benefits, Limitations and use
  for Detection

abstract:
  Recent statistics show that in 2015 more than 140 millions new malware
samples have been found. Among these, a large portion is due to ransomware, the
class of malware whose specific goal is to render the victim's system unusable,
in particular by encrypting important files, and then ask the user to pay a
ransom to revert the damage. Several ransomware include sophisticated packing
techniques, and are hence difficult to statically analyse. We present EldeRan,
a machine learning approach for dynamically analysing and classifying
ransomware. EldeRan monitors a set of actions performed by applications in
their first phases of installation checking for characteristics signs of
ransomware. Our tests over a dataset of 582 ransomware belonging to 11
families, and with 942 goodware applications, show that EldeRan achieves an
area under the ROC curve of 0.995. Furthermore, EldeRan works without requiring
that an entire ransomware family is available beforehand. These results suggest
that dynamic analysis can support ransomware detection, since ransomware
samples exhibit a set of characteristic features at run-time that are common
across families, and that helps the early detection of new variants. We also
outline some limitations of dynamic analysis for ransomware and propose
possible solutions.


title: Arlinskii's iteration and its applications

abstract:
  Several Lebesgue-type decomposition theorems in analysis have a strong
relation to the operation called: parallel sum. The aim of this paper is to
investigate this relation from a new point of view. Namely, using a natural
generalization of Arlinskii's approach (which identifies the singular part as a
fixed point of a single-variable map) we prove the existence of a Lebesgue-type
decomposition for nonnegative sesquilinear forms. As applications, we also show
that how this approach can be used to derive analogous results for
representable functionals, nonnegative finitely additive measures, and positive
definite operator functions. The focus is on the fact that each theorem can be
proved with the same completely elementary method.


title: Escape probability of the super-Penrose process

abstract:
  We consider a head-on collision of two massive particles that move in the
equatorial plane of an extremal Kerr black hole, which results in the
production of two massless particles. Focusing on a typical case, where both of
the colliding particles have zero angular momenta, we show that a massless
particle produced in such a collision can escape to infinity with arbitrarily
large energy in the near-horizon limit of the collision point. Furthermore, if
we assume that the emission of the produced massless particles is isotropic in
the center-of-mass frame but confined to the equatorial plane, the escape
probability of the produced massless particle approaches $5/12$ and almost all
escaping massless particles have arbitrarily large energy at infinity and an
impact parameter approaching $2GM/c^2$, where $M$ is the mass of the black
hole.


title: Tannakian formalism for fiber functors over tensor categories

abstract:
  In this paper we generalize Tannakian formalism to fiber functors over
general tensor categories. We will show that (under some technical conditions)
if the fiber functor has a section, then the source category is equivalent to
the category of comodules over a Hopf algebra in the target category. We will
also give a description of this Hopf algebra using the notion of framed
objects.


title:
Rectifier Neural Network with a Dual-Pathway Architecture for Image
  Denoising

abstract:
  Recently deep neural networks based on tanh activation function have shown
their impressive power in image denoising. In this letter, we try to use
rectifier function instead of tanh and propose a dual-pathway rectifier neural
network by combining two rectifier neurons with reversed input and output
weights in the same hidden layer. We drive the equivalent activation function
and compare it to some typical activation functions for image denoising under
the same network architecture. The experimental results show that our model
achieves superior performances faster especially when the noise is small.


title:
Quantum-optimal detection of one-versus-two incoherent sources with
  arbitrary separation

abstract:
  We analyze the fundamental resolution of incoherent optical point sources
from the perspective of a quantum detection problem: deciding whether the
optical field on the image plane is generated by one source or two weaker
sources with arbitrary separation. We investigate the detection performances of
two measurement methods recently proposed by us to enhance the estimation of
the separation. For the detection problem, we show that the method of binary
spatial-mode demultiplexing is quantum-optimal for all values of separations,
while the method of image-inversion interferometry is near-optimal for
sub-Rayleigh separations. Unlike the proposal by Helstrom, our schemes do not
require the separation to be given and can offer that information as a bonus in
the event of a successful detection. For comparison, we also demonstrate the
supremacy of our schemes over direct imaging for sub-Rayleigh separations.
These results demonstrate that simple linear optical measurements can offer
supremal performances for both detection and estimation.


title: Primitive pairs of K-groups

abstract:
  In 'Primitive pairs of $p$-solvable groups', J. Algebra 324 (2010) 841-859,
the author proved a non existence theorem for certain types of amalgams of
$p$-solvable groups in the presence of operator groups acting coprimely on the
groups in the amalgam. An application of that work was a new proof of the
Solvable Signalizer Functor Theorem. In this article, the $p$-solvable
restriction will be weakened to a $K$-group hypothesis. An application of this
work will be a new proof of the Nonsolvable Signalizer Functor Theorem.


title:
Lyapunov type inequality for hybrid fractional differential equation
  with Prabhakar Derivative

abstract:
  In this paper Lyapunov type inequality is developed for hybrid fractional
boundary value problem involving the prabhakar fractional derivative.


title: A characterisation of A-simple groups

abstract:
  Let $A$ be an elementary abelian $r$-group with rank at least $3$ that acts
faithfully on the finite $r'$-group $G$. Assume that $G$ is $A$-simple, so that
$G = K_{1} \times\cdots\times K_{n}$ where $K_{1},\ldots,K_{n}$ is a collection
of simple subgroups of $G$ that is permuted transitively by $A$. The purpose of
this paper is to characterize $G$ and the collection of fixed point subgroups
$\{ C_{G}(a) \;|\; a \in A^{\#} \}$. An application of this result will be a
new proof of McBride's Nonsolvable Signalizer Functor Theorem.


title:
Covariance of random stock prices in the Stochastic Dividend Discount
  Model

abstract:
  Dividend discount models have been developed in a deterministic setting. Some
authors (Hurley and Johnson, 1994 and 1998; Yao, 1997) have introduced
randomness in terms of stochastic growth rates, delivering closed-form
expressions for the expected value of stock prices. This paper extends such
previous results by determining a formula for the covariance between random
stock prices when the dividends' rates of growth are correlated. The formula is
eventually applied to real market data.


title:
Excited State Mass spectra of doubly heavy baryons $\Omega_{cc}$,
  $\Omega_{bb}$ and $\Omega_{bc}$

abstract:
  We discuss the mass spectrum of $\Omega$ baryon with two heavy quarks and one
light quark (\textit{ccs, bbs and bcs}). The main goal of the paper is to
calculate the ground state masses and after that, the positive and negative
parity excited states masses are also obtained within a Hypercentral
Constituent quark model, using coulomb plus linear potential framework. We also
added first order correction to the potential. The mass spectra upto 5S for
radial excited states and 1P-5P, 1D-4D and 1F-2F states for orbital excited
states are computed for $\Omega_{cc}$, $\Omega_{bb}$ and $\Omega_{bc}$ baryons.
Our obtained results are compared with other theoretical predictions which
could be a useful complementary tool for the interpretation of experimentaly
unknown heavy baryon spectra. The Regge trajectory is constructed in both
($n_r$, $M^{2}$) and ($J$, $M^{2}$) planes for $\Omega_{cc}$,$\Omega_{bb}$ and
$\Omega_{bc}$ baryons and their slopes and intercepts are also determined.
Magnetic moments of doubly heavy $\Omega'$s are also calculated.


title: Genus-correspondences respecting spinor genus

abstract:
  For two positive definite integral ternary quadratic forms $f$ and $g$ and a
positive integer $n$, if $n\cdot g$ is represented by $f$ and $n\cdot dg=df$,
then the pair $(f,g)$ is called a representable pair by scaling $n$. The set of
all representable pairs in $\text{gen}(f)\times \text{gen}(g)$ is called a
genus-correspondence. Jagy conjectured that if $n$ is square free and the
number of spinor genera in the genus of $f$ equals to the number of spinor
genera in the genus of $g$, then such a genus-correspondence respects spinor
genus in the sense that for any representable pairs $(f,g), (f',g')$ by scaling
$n$, $f' \in \text{spn}(f)$ if and only if $g' \in \text{spn}(g)$. In this
article, we show that by giving a counter example, Jagy's conjecture does not
hold. Furthermore, we provide a necessary and sufficient condition for a
genus-correspondence to respect spinor genus.


title: Anti-aliasing for fused filament deposition

abstract:
  Layered manufacturing inherently suffers from staircase defects along
surfaces that are gently slopped with respect to the build direction. Reducing
the slice thickness improves the situation but never resolves it completely as
flat layers remain a poor approximation of the true surface in these regions.
In addition, reducing the slice thickness largely increases the print time. In
this work we focus on a simple yet effective technique to improve the print
accuracy for layered manufacturing by filament deposition. Our method works
with standard three-axis 3D filament printers (e.g. the typical, widely
available 3D printers), using standard extrusion nozzles. It better reproduces
the geometry of sloped surfaces without increasing the print time. Our key idea
is to perform a local anti-aliasing, working at a sub-layer accuracy to produce
slightly curved deposition paths and reduce approximation errors. This is
inspired by Computer Graphics anti-aliasing techniques which consider sub-pixel
precision to treat aliasing effects. We show that the necessary deviation in
height compared to standard slicing is bounded by half the layer thickness.
Therefore, the height changes remain small and plastic deposition remains
reliable. We further split and order paths to minimize defects due to the
extruder nozzle shape, avoiding any change to the existing hardware. We apply
and analyze our approach on 3D printed examples, showing that our technique
greatly improves surface accuracy and silhouette quality while keeping the
print time nearly identical.


title: On local invariants of singular symplectic forms

abstract:
  We find a complete set of local invariants of singular symplectic forms with
the structurally stable Martinet hypersurface on a $2n$-dimensional manifold.
In the $\mathbb C$-analytic category this set consists of the Martinet
hypersurface $\Sigma _2$, the restriction of the singular symplectic form
$\omega$ to $T\Sigma_2$ and the kernel of $\omega^{n-1}$ at the point $p\in
\Sigma_2$. In the $\mathbb R$-analytic and smooth categories this set contains
one more invariant: the canonical orientation of $\Sigma_2$. We find the
conditions to determine the kernel of $\omega^{n-1}$ at $p$ by the other
invariants. In dimension $4$ we find sufficient conditions to determine the
equivalence class of a singular symplectic form-germ with the structurally
smooth Martinet hypersurface by the Martinet hypersurface and the restriction
of the singular symplectic form to it. We also study the singular symplectic
forms with singular Martinet hypersurfaces. We prove that the equivalence class
of such singular symplectic form-germ is determined by the Martinet
hypersurface, the canonical orientation of its regular part and the restriction
of the singular symplectic form to its regular part if the Martinet
hypersurface is a quasi-homogeneous hypersurface with an isolated singularity.


title:
Multiphoton amplitudes and generalized LKF transformation in scalar QED
  using the worldline formalism

abstract:
  We apply the worldline formalism to scalar quantum electrodynamics (QED) to
find a Bern-Kosower type master formula for generalized Compton scattering,
on-shell and off-shell. Moreover, we use it to study the non-perturbative gauge
parameter dependence of amplitudes in scalar QED and, as our main result, find
a simple non-perturbative transformation rule under changes of this parameter
in x-space in terms of conformal cross ratios. This generalizes the well-known
Landau-Khalatnikov-Fradkin transformation (LKFT). We also exemplify how the
LKFT works in perturbation theory.


title:
Directed Graph-based Wireless EEG Sensor Channel Selection Approach for
  Cognitive Task Classification

abstract:
  Wireless electroencephalogram (EEG) sensors have been successfully applied in
many medical and computer brain interface classifications. A common
characteristic of wireless EEG sensors is that they are low powered devices,
and hence an efficient usage of sensor energy resources is critical for any
practical application. One way of minimizing energy consumption by the EEG
sensors is by reducing the number of EEG channels participating in the
classification process. For the purpose of classifying EEG signals, we propose
a directed acyclic graph (DAG)-based channel selection algorithm. To achieve
this objective, the EEG sensor channels are first realized in a complete
undirected graph, where each channel is represented by a node. An edge between
any two nodes indicates the collaboration between these nodes in identifying
the system state; and the significance of this collaboration is quantified by a
weight assigned to the edge. The complete graph is then reduced into a directed
acyclic graph that encodes the knowledge of the non-increasing order of the
channel ranking for each cognitive task. The channel selection algorithm
utilizes this directed graph to find a maximum path such that the total weight
of this path satisfies a predefined threshold. It has been demonstrated
experimentally that channel utilization has been reduced by 50% in the worst
case scenario for a three-state system and an EEG sensor with 14 channels; and
the best classification accuracy obtained is 81%.


title:
New series representations for zeta numbers using polylogarithmic
  identities in combination with a polynomial description of Bernoulli numbers

abstract:
  With this paper we introduce a new series representation of $\zeta(3)$, which
is based on the Clausen representation of odd integer zeta values. Although,
relatively fast converging series based on the Clausen representation exist for
$\zeta(3)$, their convergence behavior is very slow compared to BBP-type
formulas, and as a consequence they are not used for explicit numerical
computations. The reason is found in the fact that the corresponding Clausen
function can be calculated analytically for a few rational arguments only,
where $x=\frac{1}{6}$ is the smallest one. Using polylogarithmic identities in
combination with a polynomial description of the even Bernoulli numbers, the
convergence behavior of the Clausen-type representation has been improved to a
level that allows us to challenge ultimately all BBP-type formulas available
for $\zeta(3)$. We present an explicit numerical comparison between one of the
best available BBP formulas and our formalism. Furthermore, we demonstrate by
an explicit computation using the first four terms in our series representation
only that $\zeta(3)$ results with an accuracy of $2*10^{-26}$, where our
computation guarantees on each approximation level for an analytical expression
for $\zeta(3)$.


title: An all-sky catalog of solar-type dwarfs for exoplanetary transit surveys

abstract:
  Most future surveys designed to discover transiting exoplanets, including
TESS and PLATO, will target bright (V<13) and nearby solar-type stars having a
spectral type later than F5. In order to enhance the probability of identifying
transits, these surveys must cover a very large area on the sky, because of the
intrinsically low areal density of bright targets. Unfortunately, no existing
catalog of stellar parameters is both deep and wide enough to provide a
homogeneous input list. As the first Gaia data release exploitable for this
purpose is expected to be released not earlier than late 2017, we have devised
an improved reduced-proper-motion method to discriminate late field dwarfs and
giants by combining UCAC4 proper motions with APASS DR6 photometry, and relying
on RAVE DR4 as an external calibrator. The output, named UCAC4-RPM, is a
publicly-available, complete all-sky catalog of solar-type dwarfs down to
V<13.5, plus an extension to logg>3.0 subgiants. The relatively low amount of
contamination (defined as the fraction of false positives; <30%) also makes
UCAC4-RPM a useful tool for the past and ongoing ground-based transit surveys,
which need to discard candidate signals originating from early-type or giant
stars. As an application, we show how UCAC4-RPM may support the preparation of
the TESS (that will map almost the entire sky) input catalog and the input
catalog of PLATO, planned to survey more than half of the whole sky with
exquisite photometric precision.


title: Self-Dual Abelian Codes in some Non-Principal Ideal Group Algebras

abstract:
  The main focus of this paper is the complete enumeration of self-dual abelian
codes in non-principal ideal group algebras $\mathbb{F}_{2^k}[A\times
\mathbb{Z}_2\times \mathbb{Z}_{2^s}]$ with respect to both the Euclidean and
Hermitian inner products, where $k$ and $s$ are positive integers and $A$ is an
abelian group of odd order. Based on the well-know characterization of
Euclidean and Hermitian self-dual abelian codes, we show that such enumeration
can be obtained in terms of a suitable product of the number of cyclic codes,
the number of Euclidean self-dual cyclic codes, and the number of Hermitian
self-dual cyclic codes of length $2^s$ over some Galois extensions of the ring
$\mathbb{F}_{2^k}+u\mathbb{F}_{2^k}$, where $u^2=0$. Subsequently, general
results on the characterization and enumeration of cyclic codes and self-dual
codes of length $p^s$ over $\mathbb{F}_{p^k}+u\mathbb{F}_{p^k}$ are given.
Combining these results, the complete enumeration of self-dual abelian codes in
$\mathbb{F}_{2^k}[A\times \mathbb{Z}_2\times \mathbb{Z}_{2^s}]$ is therefore
obtained.


title:
Experimental determination of whistler wave dispersion relation in the
  solar wind

abstract:
  The origins and properties of large amplitude whistler wave packets in the
solar wind are still unclear. In this Letter we utilise single spacecraft
electric and magnetic field waveform measurements from the ARTEMIS mission to
calculate the plasma frame frequency and wavevector of individual wave packets
over multiple intervals. This allows direct comparison of experimental
measurements with theoretical dispersion relations to identify the observed
waves as whistler waves. The whistlers are right-hand circularly polarised,
travel anti-sunward and are aligned with the background magnetic field. Their
dispersion is strongly affected by the local electron parallel beta in
agreement with linear theory. The properties measured are consistent with the
electron heat flux instability acting in the solar wind to generate these
waves.


title:
The physical properties of Spitzer/IRS galaxies derived from their UV to
  22 $\mu$m spectral energy distribution

abstract:
  We provide the basic integrated physical properties of all the galaxies
contained in the full CASSIS with available broad-band photometry from UV to 22
$\mu$m. We have collected photometric measurements in 14 wavelengths from
available public surveys in order to study the SED of each galaxy in CASSIS,
thus constructing a final sample of 1,146 galaxies in the redshift range
0<z<2.5. The SEDs are modelled with the CIGALE code which relies on the energy
balance between the absorbed stellar and the dust emission while taking into
account the possible contribution due to the presence of an AGN. We split the
galaxies in three groups, a low-redshift, a mid-redshift and a high-redshift
and find that the vast majority of the Spitzer/IRS galaxies are star-forming
and lie on or above the star-forming MS of the corresponding redshift.
Moreover, the emission of Spitzer/IRS galaxies with z<0.1 is mostly dominated
by star-formation, galaxies in the mid-redshift bin are a mixture of star
forming and AGN galaxies, while half of the galaxies with z<0.5 show moderate
or high AGN activity. Additionally, using rest-frame NUV-r colour, S\'ersic
indices, optical OIII and NII emission lines we explore the nature of these
galaxies by investigating their structure as well as their star-formation and
AGN activity. Using a colour magnitude diagram we confirm that 97% of the
galaxies with redshift smaller than 0.5 have experienced a recent
star-formation episode. For a sub-sample of galaxies with available structural
information and redshift smaller than 0.3 we find that early-type galaxies are
placed below the MS, while late-type galaxies are found on the MS as expected.
Finally, for all the galaxies with z<0.5 and available optical spectral line
measurements we find that galaxies with high AGN luminosity, as calculated by
CIGALE, are most likely to be classified as composite or AGNs by optical
spectral lines.


title: Optical tomography on graphs

abstract:
  We present an algorithm for solving inverse problems on graphs analogous to
those arising in diffuse optical tomography for continuous media. In
particular, we formulate and analyze a discrete version of the inverse Born
series, proving estimates characterizing the domain of convergence,
approximation errors, and stability of our approach. We also present a
modification which allows additional information on the structure of the
potential to be incorporated, facilitating recovery for a broader class of
problems.


title: Numerical magneto-hydrodynamics for relativistic nuclear collisions

abstract:
  We present an improved version of the ECHO-QGP numerical code, which
self-consistently includes for the first time the effects of electromagnetic
fields within the framework of relativistic magnetohydrodynamics (RMHD). We
discuss results of its application in relativistic heavy-ion collisions in the
limit of infinite electrical conductivity of the plasma. After reviewing the
relevant covariant $3\!+\!1$ formalisms, we illustrate the implementation of
the evolution equations in the code and show the results of several tests aimed
at assessing the accuracy and robustness of the implementation. After providing
some estimates of the magnetic fields arising in non-central high-energy
nuclear collisions, we perform full RMHD simulations of the evolution of the
Quark-Gluon Plasma in the presence of electromagnetic fields and discuss the
results. In our ideal RMHD setup we find that the magnetic field developing in
non-central collisions does not significantly modify the elliptic-flow of the
final hadrons. However, since there are uncertainties in the description of the
pre-equilibrium phase and also in the properties of the medium, a more
extensive survey of the possible initial conditions as well as the inclusion of
dissipative effects are indeed necessary to validate this preliminary result.


title: The kinematic formula in the 3D-Heisenberg group

abstract:
  By studying the group of rigid motions, $PSH(1)$, in the 3D-Heisenberg group
$H_1$, we define the density and the measure for the sets of horizontal lines.
We show that the volume of a convex domain $D\subset H_1$ is equal to the
integral of length of chord over all horizontal lines intersecting $D$. As the
classical result in integral geometry, we also define the kinematic density for
$PSH(1)$ and show the probability of randomly throwing a vector $v$ interesting
the convex domain $D\subset D_0$ under the condition that $v$ is contained in
$D_0$. Both results show the relationship connecting the geometric probability
and the natural geometric quantity in Cheng-Hwang-Malchiodi-Yang's work
approached by the variational method.


title:
From glass formation to icosahedral ordering by curving
  three-dimensional space

abstract:
  Geometric frustration describes the inability of a local molecular
arrangement, such as icosahedra found in metallic glasses and in model atomic
glass-formers, to tile space. Local icosahedral order however is strongly
frustrated in Euclidean space, which obscures any causal relationship with the
observed dynamical slowdown. Here we relieve frustration in a model
glass-forming liquid by curving 3-dimensional space onto the surface of a
4-dimensional hypersphere. For sufficient curvature, frustration vanishes and
the liquid freezes in a fully icosahedral structure via a sharp `transition'.
Frustration increases upon reducing the curvature, and the transition to the
icosahedral state smoothens while glassy dynamics emerges. Decreasing the
curvature leads to decoupling between dynamical and structural length scales
and the decrease of kinetic fragility. This sheds light on the observed
glass-forming behavior in the Euclidean space.


title:
Principal component analysis and the locus of the Frechet mean in the
  space of phylogenetic trees

abstract:
  Most biological data are multidimensional, posing a major challenge to human
comprehension and computational analysis. Principal component analysis is the
most popular approach to rendering two- or three-dimensional representations of
the major trends in such multidimensional data. The problem of
multidimensionality is acute in the rapidly growing area of phylogenomics.
Evolutionary relationships are represented by phylogenetic trees, and very
typically a phylogenomic analysis results in a collection of such trees, one
for each gene in the analysis. Principal component analysis offers a means of
quantifying variation and summarizing a collection of phylogenies by
dimensional reduction. However, the space of all possible phylogenies on a
fixed set of species does not form a Euclidean vector space, so principal
component analysis must be reformulated in the geometry of tree-space, which is
a CAT(0) geodesic metric space. Previous work has focused on construction of
the first principal component, or principal geodesic. Here we propose a
geometric object which represents a $k$-th order principal component: the locus
of the weighted Fr\'echet mean of $k+1$ points in tree-space, where the weights
vary over the standard $k$-dimensional simplex. We establish basic properties
of these objects, in particular that locally they generically have dimension
$k$, and we propose an efficient algorithm for projection onto these surfaces.
Combined with a stochastic optimization algorithm, this projection algorithm
gives a procedure for constructing a principal component of arbitrary order in
tree-space. Simulation studies confirm these algorithms perform well, and they
are applied to data sets of Apicomplexa gene trees and the African coelacanth
genome. The results enable visualizations of slices of tree-space, revealing
structure within these complex data sets.


title: Properly convex bending of hyperbolic manifolds

abstract:
  In this paper we show that bending a finite volume hyperbolic $d$-manifold
$M$ along a totally geodesic hypersurface $\Sigma$ results in a properly convex
projective structure on $M$ with finite volume. We also discuss various
geometric properties of bent manifolds and algebraic properties of their
fundamental groups. We then use this result to show in each dimension $d\geq 3$
there are examples finite volume, but non-compact, properly convex
$d$-manifolds. Furthermore, we show that the examples can be chosen to be
either strictly convex or non-strictly convex.


title: Autonomous collision attack on OCSP services

abstract:
  The paper describes two important design flaws in Online Certificate Status
Protocol (OCSP), a protocol widely used in PKI environments for managing
digital certificates' credibility in real time. The flaws significantly reduce
the security capabilities of the protocol, and can be exploited by a malicious
third party to generate forged signed certificate statuses and, in the worst
scenario, forged certificates. Description of the flaws, along with expected
exploitation routes, consequences for consuming application layer protocols,
and proposed countermeasures, is given.


title: Reentrant spinodals and the Speedy scenario in colloidal model systems

abstract:
  A re-entrant gas-liquid spinodal was proposed as a possible explanation of
the apparent divergence of the compressibility and specific heat on
supercooling water. Such a counter intuitive possibility, e.g. a liquid that
becomes unstable to gas-like fluctuations on cooling at positive pressure, has
never been observed, neither in real substances nor in off-lattice simulations.
More recently, such re-entrant scenario has been dismissed on the premise that
the re-entrant spinodal would collide with the gas-liquid binodal in the
pressure-temperature plane. Here we study, numerically and analytically, two
previously introduced one-component patchy particle models that both show (i) a
re-entrant spinodal and (ii) a re-entrant binodal, providing a neat in silico
(and in charta) realization of such unconventional thermodynamic scenario.


title:
The excluded minors for the class of matroids that are graphic or
  bicircular lift

abstract:
  Bicircular lift matroids are a class of matroids defined on the edge set of a
graph. For a given graph $G$, the circuits of its bicircular lift matroid
$L(G)$ are the edge sets of those subgraphs of $G$ that contain at least two
cycles, and are minimal with respect to this property. For each cycle $C$ of
$G$, since $L(G)/C$ is graphic and most graphic matroids are not bicircular
lift, the class of bicircular lift matroids is not minor-closed. In this paper,
we prove that the class of matroids that are graphic or bicircular lift has a
finite list of excluded minors.


title: Dropout Prediction in Crowdsourcing Markets

abstract:
  Crowdsourcing environments have shown promise in solving diverse tasks in
limited cost and time. This type of business model involves both the expert and
non-expert workers. Interestingly, the success of such models depends on the
volume of the total number of workers. But, the survival of the fittest
controls the stability of these workers. Here, we show that the crowd workers
who fail to win jobs successively loose interest and might dropout over time.
Therefore, dropout prediction in such environments is a promising task. In this
paper, we establish that it is possible to predict the dropouts in a
crowdsourcing market from the success rate based on the arrival pattern of
workers.


title: Molecular Lines of 13 Galactic Infrared Bubble Regions

abstract:
  We investigated the physical properties of molecular clouds and star
formation processes around infrared bubbles which are essentially expanding HII
regions. We performed observations of 13 galactic infrared bubble fields
containing 18 bubbles. Five molecular lines, 12CO (J=1-0), 13CO (J=1-0),
C18O(J=1-0), HCN (J=1-0), and HCO+ (J=1-0), were observed, and several publicly
available surveys, GLIMPSE, MIPSGAL, ATLASGAL, BGPS, VGPS, MAGPIS, and NVSS,
were used for comparison. We find that these bubbles are generally connected
with molecular clouds, most of which are giant. Several bubble regions display
velocity gradients and broad shifted profiles, which could be due to the
expansion of bubbles. The masses of molecular clouds within bubbles range from
100 to 19,000 solar mass, and their dynamic ages are about 0.3-3.7 Myr, which
takes into account the internal turbulence pressure of surrounding molecular
clouds. Clumps are found in the vicinity of all 18 bubbles, and molecular
clouds near four of these bubbles with larger angular sizes show shell-like
morphologies, indicating that either collect-and-collapse or radiation-driven
implosion processes may have occurred. Due to the contamination of adjacent
molecular clouds, only six bubble regions are appropriate to search for
outflows, and we find that four of them have outflow activities. Three bubbles
display ultra-compact HII regions at their borders, and one of them is probably
responsible for its outflow. In total, only six bubbles show star formation
activities in the vicinity, and we suggest that star formation processes might
have been triggered.


title: Hadron spectroscopy and interactions from lattice QCD

abstract:
  Lattice QCD approach to study the hadronic resonances and exotic hadrons is
described at an introductory level. The main challenge is that these states
decay strongly via one or more decay channels, and they often lie near
thersholds. Specific results for conventional and exotic hadrons are shown to
illustrate the current status.


title: GEMPIC: Geometric ElectroMagnetic Particle-In-Cell Methods

abstract:
  We present a novel framework for Finite Element Particle-in-Cell methods
based on the discretization of the underlying Hamiltonian structure of the
Vlasov-Maxwell system. We derive a semi-discrete Poisson bracket, which retains
the defining properties of a bracket, anti-symmetry and the Jacobi identity, as
well as conservation of its Casimir invariants, implying that the semi-discrete
system is still a Hamiltonian system. In order to obtain a fully discrete
Poisson integrator, the semi-discrete bracket is used in conjunction with
Hamiltonian splitting methods for integration in time. Techniques from Finite
Element Exterior Calculus ensure conservation of the divergence of the magnetic
field and Gauss' law as well as stability of the field solver. The resulting
methods are gauge invariant, feature exact charge conservation and show
excellent long-time energy and momentum behaviour. Due to the generality of our
framework, these conservation properties are guaranteed independently of a
particular choice of the Finite Element basis, as long as the corresponding
Finite Element spaces satisfy certain compatibility conditions.


title: New Steps on the Exact Learning of CNF

abstract:
  A major problem in computational learning theory is whether the class of
formulas in conjunctive normal form (CNF) is efficiently learnable. Although it
is known that this class cannot be polynomially learned using either membership
or equivalence queries alone, it is open whether CNF can be polynomially
learned using both types of queries. One of the most important results
concerning a restriction of the class CNF is that propositional Horn formulas
are polynomial time learnable in Angluin's exact learning model with membership
and equivalence queries. In this work we push this boundary and show that the
class of multivalued dependency formulas (MVDF) is polynomially learnable from
interpretations. We then provide a notion of reduction between learning
problems in Angluin's model, showing that a transformation of the algorithm
suffices to efficiently learn multivalued database dependencies from data
relations. We also show via reductions that our main result extends well known
previous results and allows us to find alternative solutions for them.


title:
Einstein Finsler Metrics and Killing Vector Fields on Riemannian
  Manifolds

abstract:
  In this paper, we use a Killing form on a Riemannian manifold to construct a
class of Finsler metrics. We find equations that characterize Einstein metrics
among this class. In particular, we construct a family of Einstein metrics on
$S^3$ with ${\rm Ric} = 2 F^2$, ${\rm Ric}=0$ and ${\rm Ric}=- 2 F^2$,
respectively. This family of metrics provide an important class of Finsler
metrics in dimension three, whose Ricci curvature is a constant, but the flag
curvature is not.


title:
Sequential Deep Trajectory Descriptor for Action Recognition with
  Three-stream CNN

abstract:
  Learning the spatial-temporal representation of motion information is crucial
to human action recognition. Nevertheless, most of the existing features or
descriptors cannot capture motion information effectively, especially for
long-term motion. To address this problem, this paper proposes a long-term
motion descriptor called sequential Deep Trajectory Descriptor (sDTD).
Specifically, we project dense trajectories into two-dimensional planes, and
subsequently a CNN-RNN network is employed to learn an effective representation
for long-term motion. Unlike the popular two-stream ConvNets, the sDTD stream
is introduced into a three-stream framework so as to identify actions from a
video sequence. Consequently, this three-stream framework can simultaneously
capture static spatial features, short-term motion and long-term motion in the
video. Extensive experiments were conducted on three challenging datasets: KTH,
HMDB51 and UCF101. Experimental results show that our method achieves
state-of-the-art performance on the KTH and UCF101 datasets, and is comparable
to the state-of-the-art methods on the HMDB51 dataset.


title: Style-Transfer via Texture-Synthesis

abstract:
  Style-transfer is a process of migrating a style from a given image to the
content of another, synthesizing a new image which is an artistic mixture of
the two. Recent work on this problem adopting Convolutional Neural-networks
(CNN) ignited a renewed interest in this field, due to the very impressive
results obtained. There exists an alternative path towards handling the
style-transfer task, via generalization of texture-synthesis algorithms. This
approach has been proposed over the years, but its results are typically less
impressive compared to the CNN ones.
  In this work we propose a novel style-transfer algorithm that extends the
texture-synthesis work of Kwatra et. al. (2005), while aiming to get stylized
images that get closer in quality to the CNN ones. We modify Kwatra's algorithm
in several key ways in order to achieve the desired transfer, with emphasis on
a consistent way for keeping the content intact in selected regions, while
producing hallucinated and rich style in others. The results obtained are
visually pleasing and diverse, shown to be competitive with the recent CNN
style-transfer algorithms. The proposed algorithm is fast and flexible, being
able to process any pair of content + style images.


title:
A Tube-and-Droplet-based Approach for Representing and Analyzing Motion
  Trajectories

abstract:
  Trajectory analysis is essential in many applications. In this paper, we
address the problem of representing motion trajectories in a highly informative
way, and consequently utilize it for analyzing trajectories. Our approach first
leverages the complete information from given trajectories to construct a
thermal transfer field which provides a context-rich way to describe the global
motion pattern in a scene. Then, a 3D tube is derived which depicts an input
trajectory by integrating its surrounding motion patterns contained in the
thermal transfer field. The 3D tube effectively: 1) maintains the movement
information of a trajectory, 2) embeds the complete contextual motion pattern
around a trajectory, 3) visualizes information about a trajectory in a clear
and unified way. We further introduce a droplet-based process. It derives a
droplet vector from a 3D tube, so as to characterize the high-dimensional 3D
tube information in a simple but effective way. Finally, we apply our
tube-and-droplet representation to trajectory analysis applications including
trajectory clustering, trajectory classification & abnormality detection, and
3D action recognition. Experimental comparisons with state-of-the-art
algorithms demonstrate the effectiveness of our approach.


title: Trees with Equal Total Domination and Game Total Domination Numbers

abstract:
  In this paper, we continue the study of the total domination game in graphs
introduced in [Graphs Combin. 31(5) (2015), 1453--1462], where the players
Dominator and Staller alternately select vertices of $G$. Each vertex chosen
must strictly increase the number of vertices totally dominated, where a vertex
totally dominates another vertex if they are neighbors. This process eventually
produces a total dominating set $S$ of $G$ in which every vertex is totally
dominated by a vertex in $S$. Dominator wishes to minimize the number of
vertices chosen, while Staller wishes to maximize it. The game total domination
number, $\gamma_{\rm tg}(G)$, (respectively, Staller-start game total
domination number, $\gamma_{\rm tg}'(G)$) of $G$ is the number of vertices
chosen when Dominator (respectively, Staller) starts the game and both players
play optimally. For general graphs $G$, sometimes $\gamma_{\rm tg}(G) >
\gamma_{\rm tg}'(G)$. We show that if $G$ is a forest with no isolated vertex,
then $\gamma_{\rm tg}(G) \le \gamma_{\rm tg}'(G)$. Using this result, we
characterize the trees with equal total domination and game total domination
number.


title: Double asymptotics for the chi-square statistic

abstract:
  We consider distributional limit of the Pearson chi-square statistic when the
number of classes m increases with the sample size n in such way that
$n/\sqrt{m} \to {\lambda}$. Under mild moment conditions, the limit is Gaussian
for ${\lambda} = \infty$, Poisson for finite ${\lambda} > 0$, and degenerate
for ${\lambda} = 0$.


title:
The Thermodynamical Instability Induced by Pressure Ionization in Fluid
  Helium

abstract:
  A systematic study of pressure ionization is carried out in the chemical
picture by the example of fluid helium. By comparing the variants of the
chemical model, it is demonstrated that the behavior of pressure ionization
depends on the construction of the free energy function. In the chemical model
with the Coulomb free energy described by the Pad\'e interpolation formula,
thermodynamical instability induced by pressure ionization is found to be
manifested by a discontinuous drop or a continuous fall and rise along the
pressure-density curve as well as the pressure-temperature curve, which is very
much like the first order liquid-liquid phase transition of fluid hydrogen from
the first principles simulations. In contrast, in the variant chemical model
with the Coulomb free energy term empirically weakened, no thermodynamical
instability is induced when pressure ionization occurs, and the resulting
equation of state achieves good agreement with the first principles simulations
of fluid helium.


title: {\omega}-Automata

abstract:
  This paper gives a concise introduction into the basic theory of
{\omega}-automata (as of March 2014). The starting point are the different
types of recurrence conditions, modes of operation (deterministic,
nondeterministic, alternating automata), and directions (forward or backward
automata). The main focus is on fundamental automata constructions, for
instance, for boolean operations, determinization, disambiguation, and removing
alternation. It also covers some algebraic aspects such as congruences for
{\omega}-automata (and {\omega}-languages), basic structure theory (loops), and
applications in mathematical logic. This paper may eventually become a chapter
in a handbook of automata theory.


title:
Thermal Transport Across Metal Silicide-Silicon Interfaces:
  First-Principles Calculations and Green's Function Transport Simulations

abstract:
  In this work, we use a combination of first-principles calculations under the
density functional theory framework and heat transport simulations using the
atomistic Green's function (AGF) method to quantitatively predict the
contribution of the different scattering mechanisms to the thermal interface
conductance of epitaxial CoSi$_2$-Si interfaces. An important development in
the present work is the direct computation of interfacial bonding from density
functional perturbation theory (DFPT) and hence the avoidance of commonly used
`mixing rules' to obtain the cross-interface force constants from bulk material
force constants. Another important algorithmic development is the integration
of the recursive Green's function (RGF) method with B\"{u}ttiker probe
scattering that enables computationally efficient simulations of inelastic
phonon scattering and its contribution to the thermal interface conductance.
First-principles calculations of electron-phonon coupling reveal that
cross-interface energy transfer between metal electrons and atomic vibrations
in the semiconductor is mediated by delocalized acoustic phonon modes that
extend on both sides of the interface, and phonon modes that are localized
inside the semiconductor region of the interface exhibit negligible coupling
with electrons in the metal. We also provide a direct comparison between
simulation predictions and experimental measurements of thermal interface
conductance of epitaxial CoSi$_2$-Si interfaces using the time-domain
thermoreflectance technique. Importantly, the experimental results, performed
across a wide temperature range, only agree well with predictions that include
all transport processes: elastic and inelastic phonon scattering,
electron-phonon coupling in the metal, and electron-phonon coupling across the
interface.


title:
Squeezed Coherent States of Motion for Ions Confined in Quadrupole and
  Octupole Ion Traps

abstract:
  Quasiclassical dynamics of trapped ions is characterized by applying the time
dependent variational principle (TDVP) on coherent state orbits, in case of
quadrupole and octupole combined (Paul and Penning) and radiofrequency (RF)
traps. A dequantization algorithm is proposed, by which the classical Hamilton
(energy) function associated to the system results as the expectation value of
the quantum Hamiltonian on squeezed coherent states. We develop such method and
particularize the quantum Hamiltonian for a combined and for a RF trap, with
axial symmetry and a RF anharmonic electric potential. We also build the
classical Hamiltonian functions for the particular traps we considered, and
find the classical equations of motion.


title:
Probabilistic Cross-Identification in Crowded Fields as an Assignment
  Problem

abstract:
  One of the outstanding challenges of cross-identification is multiplicity:
detections in crowded regions of the sky are often linked to more than one
candidate associations of similar likelihoods. We map the resulting maximum
likelihood partitioning to the fundamental assignment problem of discrete
mathematics and efficiently solve the two-way catalog-level matching in the
realm of combinatorial optimization using the so-called Hungarian algorithm. We
introduce the method, demonstrate its performance in a mock universe where the
true associations are known, and discuss the applicability of the new procedure
to large surveys.


title: Creating new layered structures at high pressures: SiS$_2$

abstract:
  Old and novel layered structures are attracting increasing attention for
their physical, electronic, and frictional properties. SiS$_2$, isoelectronic
to SiO$_2$, CO$_2$ and CS$_2$, is a material whose phases known experimentally
up to 6 GPa exhibit 1D chain-like, 2D layered and 3D tetrahedral structures. We
present highly predictive $ab$ $initio$ calculations combined with evolutionary
structure search and molecular dynamics simulations of the structural and
electronic evolution of SiS$_2$ up to 100 GPa. A highly stable CdI$_2$-type
layered structure, which is octahedrally coordinated with space group
$P\bar{3}m1$ surprisingly appears between 4 and up to at least 100 GPa. The
tetrahedral-octahedral switch is naturally expected upon compression, unlike
the layered character realized here by edge-sharing SiS$_6$ octahedral units
connecting within but not among sheets. The predicted phase is semiconducting
with an indirect band gap of about 2 eV at 10 GPa, decreasing under pressure
until metallization around 40 GPa. The robustness of the layered phase suggests
possible recovery at ambient pressure, where calculated phonon spectra indicate
dynamical stability. Even a single monolayer is found to be dynamically stable
in isolation, suggesting that it could possibly be sheared or exfoliated from
bulk $P\bar{3}m1$-SiS$_2$.


title:
Quantifying the informativeness for biomedical literature summarization:
  An itemset mining method

abstract:
  Objective: Automatic text summarization tools can help users in the
biomedical domain to access information efficiently from a large volume of
scientific literature and other sources of text documents. In this paper, we
propose a summarization method that combines itemset mining and domain
knowledge to construct a concept-based model and to extract the main subtopics
from an input document. Our summarizer quantifies the informativeness of each
sentence using the support values of itemsets appearing in the sentence.
Methods: To address the concept-level analysis of text, our method initially
maps the original document to biomedical concepts using the UMLS. Then, it
discovers the essential subtopics of the text using a data mining technique,
namely itemset mining, and constructs the summarization model. The employed
itemset mining algorithm extracts a set of frequent itemsets containing
correlated and recurrent concepts of the input document. The summarizer selects
the most related and informative sentences and generates the final summary.
Results: We evaluate the performance of our itemset-based summarizer using the
Recall-Oriented Understudy for Gisting Evaluation (ROUGE) metrics, performing a
set of experiments. The results show that the itemset-based summarizer performs
better than the compared methods. The itemset-based summarizer achieves the
best scores for all the assessed ROUGE metrics . Conclusion: Compared to the
statistical, similarity, and word frequency methods, the proposed method
demonstrates that the summarization model obtained from the concept extraction
and itemset mining provides the summarizer with an effective metric for
measuring the informative content of sentences. This can lead to an improvement
in the performance of biomedical literature summarization.


title:
Multiplex visibility graphs to investigate recurrent neural networks
  dynamics

abstract:
  A recurrent neural network (RNN) is a universal approximator of dynamical
systems, whose performance often depends on sensitive hyperparameters. Tuning
of such hyperparameters may be difficult and, typically, based on a
trial-and-error approach. In this work, we adopt a graph-based framework to
interpret and characterize the internal RNN dynamics. Through this insight, we
are able to design a principled unsupervised method to derive configurations
with maximized performances, in terms of prediction error and memory capacity.
In particular, we propose to model time series of neurons activations with the
recently introduced horizontal visibility graphs, whose topological properties
reflect important dynamical features of the underlying dynamic system.
Successively, each graph becomes a layer of a larger structure, called
multiplex. We show that topological properties of such a multiplex reflect
important features of RNN dynamics and are used to guide the tuning procedure.
To validate the proposed method, we consider a class of RNNs called echo state
networks. We perform experiments and discuss results on several benchmarks and
real-world dataset of call data records.


title: Vortex disruption by magnetohydrodynamic feedback

abstract:
  In an electrically conducting fluid, vortices stretch out a weak, large-scale
magnetic field to form strong current sheets on their edges. Associated with
these current sheets are magnetic stresses, which are subsequently released
through reconnection, leading to vortex disruption, and possibly even
destruction. This disruption phenomenon is investigated here in the context of
two-dimensional, homogeneous, incompressible magnetohydrodynamics. We derive a
simple order of magnitude estimate for the magnetic stresses --- and thus the
degree of disruption --- that depends on the strength of the background
magnetic field (measured by the parameter $M$, a ratio between the Alfv\'en
speed and a typical flow speed) and on the magnetic diffusivity (measured by
the magnetic Reynolds number $\mbox{Rm}$). The resulting estimate suggests that
significant disruption occurs when $M^{2}\mbox{Rm} = O(1)$. To test our
prediction, we analyse direct numerical simulations of vortices generated by
the breakup of unstable shear flows with an initially weak background magnetic
field. Using the Okubo--Weiss vortex coherence criterion, we introduce a vortex
disruption measure, and show that it is consistent with our predicted scaling,
for vortices generated by instabilities of both a shear layer and a jet.


title: Distribution of Shapes of orthogonal Lattices

abstract:
  It was recently shown by Aka, Einsiedler and Shapira that if d>2, the set of
primitive vectors on large spheres when projected to the d-1-dimensional sphere
coupled with the shape of the lattice in their orthogonal complement
equidistribute in the product space of the sphere with the space of shapes of
d-1-dimensional lattices. Specifically, for d=3,4,5 some congruence conditions
are assumed. By using recent advances in the theory of unipotent flows, we
effectivize the dynamical proof to remove those conditions for d=4,5. It also
follows that equidistribution takes place with a polynomial error term with
respect to the length of the primitive points.


title: Angular resolution of stacked resistive plate chambers

abstract:
  We present here detailed derivations of mathematical expressions for the
accuracy in the arrival direction of particles estimated using a set of stacked
resistive plate chambers (RPCs). The expressions are validated against
experimental results using data collected from the prototype detectors (without
magnet) of the upcoming India-based Neutrino Observatory (INO). We also present
a theoretical estimate of angular resolution of such a setup. In principle,
these expressions can be used for any other detector with an architecture
similar to that of RPCs.


title:
Prospects for Detecting Galactic Sources of Cosmic Neutrinos with
  IceCube: An Update

abstract:
  Air-Cherenkov telescopes have mapped the Galactic plane at TeV energies. Here
we evaluate the prospects for detecting the neutrino emission from sources in
the Galactic plane assuming that the highest energy photons originate from the
decay of pions, which yields a straightforward prediction for the neutrino flux
from the decay of the associated production of charged pions. Four promising
sources are identified based on having a large flux and a flat spectrum. We
subsequently evaluate the probability of their identification above the
atmospheric neutrino background in IceCube data as a function of time. We show
that observing them over the twenty-year lifetime of the instrumentation is
likely, and that some should be observable at the $3\,\sigma$ level with six
years of data. In the absence of positive results, we derive constraints on the
spectral index and cut-off energy of the sources, assuming a hadronic
acceleration mechanism.


title:
BAUM: A DNA Assembler by Adaptive Unique Mapping and Local
  Overlap-Layout-Consensus

abstract:
  Genome assembly from the high-throughput sequencing (HTS) reads is a
fundamental yet challenging computational problem. An intrinsic challenge is
the uncertainty caused by the widespread repetitive elements. Here we get
around the uncertainty using the notion of uniquely mapped (UM) reads, which
motivated the design of a new assembler BAUM. It mainly consists of two types
of iterations. The first type of iterations constructs initial contigs from a
reference, say a genome of a species that could be quite distant, by adaptive
read mapping, filtration by the reference's unique regions, and reference
updating. A statistical test is proposed to split the layouts at possible
structural variation sites. The second type of iterations includes mapping,
scaffolding/contig-extension, and contig merging. We extend each contig by
locally assembling the reads whose mates are uniquely mapped to an end of the
contig. Instead of the de Bruijn graph method, we take the
overlap-layout-consensus (OLC) paradigm. The OLC is implemented by parallel
computation, and has linear complexity with respect to the number of contigs.
The adjacent extended contigs are merged if their alignment is confirmed by the
adjusted gap distance. Throughout the assembling, the mapping criterion is
selected by probabilistic calculations. These innovations can be used
complementary to the existing de novo assemblers. Applying this novel method to
the assembly of wild rice Oryza longistaminata genome, we achieved much
improved contig N50, 18.8k, compared with other assemblers. The assembly was
further validated by contigs constructed from an independent library of long
454 reads.


title: A Topological Completeness Theorem for Transfinite Provability Logic

abstract:
  We prove a topological completeness theorem for the modal logic GLP
containing operators $\langle\lambda\rangle$ for $\lambda \in$ Ord intended to
capture progressively stronger notions of consistency in mathematical theories.
We show that, given a scattered space $X$ of large-enough rank, any sentence
$\phi$ consistent with GLP can be satisfied in a polytopological space based on
the finitely many Icard topologies over $X$ that correspond to the finitely
many modalities appearing in $\phi$.


title: Geometric and Information-Theoretic Properties of the Hoggar Lines

abstract:
  We take a tour of a set of equiangular lines in eight-dimensional Hilbert
space. This structure defines an informationally complete measurement, that is,
a way to represent all quantum states of three-qubit systems as probability
distributions. Investigating the shape of this representation of state space
yields a pattern of connections among a remarkable spread of mathematical
constructions. In particular, studying the Shannon entropy of probabilistic
representations of quantum states leads to an intriguing link between the
questions of real and of complex equiangular lines. Furthermore, we will find
relations between quantum information theory and mathematical topics like
octonionic integers and the 28 bitangents to a quartic curve.


title: Guided Policy Search with Delayed Sensor Measurements

abstract:
  Guided policy search is a method for reinforcement learning that trains a
general policy for accomplishing a given task by guiding the learning of the
policy with multiple guiding distributions. Guided policy search relies on
learning an underlying dynamical model of the environment and then, at each
iteration of the algorithm, using that model to gradually improve the policy.
This model, though, often makes the assumption that the environment dynamics
are markovian, e.g., depend only on the current state and control signal. In
this paper we apply guided policy search to a problem with non-markovian
dynamics. Specifically, we apply it to the problem of pouring a precise amount
of liquid from a cup into a bowl, where many of the sensor measurements
experience non-trivial amounts of delay. We show that, with relatively simple
state augmentation, guided policy search can be extended to non-markovian
dynamical systems, where the non-markovianess is caused by delayed sensor
readings.


title:
Electronic coarse graining enhances the predictive power of molecular
  simulation allowing challenges in water physics to be addressed

abstract:
  One key factor that limits the predictive power of molecular dynamics
simulations is the accuracy and transferability of the input force field. Force
fields are challenged by heterogeneous environments, where electronic responses
give rise to biologically important forces such as many-body polarisation and
dispersion. The importance of polarisation was recognised early-on and
described by Cochran in 1959 [Philosophical Magazine 4 (1959) 1082-1086].
However, dispersion forces are still treated at the two-body level and in the
dipole limit, although the importance of three-body terms in the condensed
phase was demonstrated by Barker in the 1980s [Phys. Rev. Lett. 57 (1986)
230-233]. A way of treating both polarisation and dispersion on an equal basis
is to coarse grain the electrons a molecular moiety to a single quantum
harmonic oscillator, as suggested as early as the 1960s by Hirschfelder,
Curtiss and Bird [The Molecular Theory of Gases and Liquids (1954)]. This
treatment, when solved in the strong coupling limit, gives all orders of
long-range forces. In the last decade, the tools necessary to exploit this
strong coupling limit have been developed, culminating in a transferable model
of water with excellent predictive power across the phase diagram. This
transferability arises since the environment identifies the form of long range
interactions, rather than the expressions selected by the modeller. Here, we
discuss the role of electronic coarse-graining in predictive multiscale
materials modelling and describe the first implementation of the method in a
general purpose molecular dynamics software, QDO_MD.


title: Solovay's inaccessible over a weak set theory without choice

abstract:
  We study the consistency strength of Lebesgue measurability for $\Sigma^1_3$
sets over a weak set theory in a completely choiceless context. We establish a
result analogous to the Solovay-Shelah theorem.


title: Semi-classical Approach to Quantum Spin Ice

abstract:
  We propose a semi-classical description of the low-energy properties of
quantum spin ice in the strong Ising limit. Within the framework of a
semiclassical, perturbative Villain expansion, that can be truncated at
arbitrary order, we give an analytic and quantitative treatment of the
deconfining phase. We find that photon-photon interactions significantly
renormalise the speed of light and split the two transverse photon
polarisations at intermediate wavevectors. We calculate the photon velocity and
the ground state energy to first and second order in perturbation theory,
respectively. The former is in good agreement with recent numerical
simulations.


title: On the adiabatic limit of Hadamard states

abstract:
  We consider the adiabatic limit of Hadamard states for free quantum
Klein-Gordon fields, when the background metric and the field mass are slowly
varied from their initial to final values. If the Klein-Gordon field stays
massive, we prove that the adiabatic limit of the initial vacuum state is the
(final) vacuum state, by extending to the symplectic framework the adiabatic
theorem of Avron-Seiler-Yaffe. In cases when only the field mass is varied,
using a abstract version of the mode decomposition method we can also consider
the case when the initial or final mass vanishes, and the initial state is
either a thermal state or a more general Hadamard state.


title:
Optimal Hardy--Littlewood inequalities uniformly bounded by a universal
  constant

abstract:
  The Hardy--Littlewood inequality for $m$-linear forms on $\ell _{p}$ spaces
and $m<p\leq 2m$ asserts that \begin{equation*} \left(
\sum_{j_{1},...,j_{m}=1}^{\infty }\left\vert T\left( e_{j_{1}},\ldots
,e_{j_{m}}\right) \right\vert ^{\frac{p}{p-m}}\right) ^{\frac{p-m}{p}}\leq
2^{\frac{m-1}{2}}\left\Vert T\right\Vert \end{equation*} for all continuous
$m$-linear forms $T:\ell _{p}\times \cdots \times \ell _{p}\rightarrow
\mathbb{R}$ or $\mathbb{C}.$ The case $m=2$ recovers a classical inequality
proved by Hardy and Littlewood in 1934. As a consequence of the results of the
present paper we show that the same inequality is valid with
$2^{\frac{m-1}{2}}$ replaced by $2^{\frac{\left( m-1\right) \left( p-m\right)
}{p}}$. In particular, for $m<p\leq m+1$ the optimal constants of the above
inequality are uniformly bounded by $2.$


title:
Atmospheric characterization of Proxima b by coupling the Sphere
  high-contrast imager to the Espresso spectrograph

abstract:
  Context. The temperate Earth-mass planet Proxima b is the closest exoplanet
to Earth and represents what may be our best ever opportunity to search for
life outside the Solar System. Aims. We aim at directly detecting Proxima b and
characterizing its atmosphere by spatially resolving the planet and obtaining
high-resolution reflected-light spectra. Methods. We propose to develop a
coupling interface between the SPHERE high-contrast imager and the new ESPRESSO
spectrograph, both installed at ESO VLT. The angular separation of 37 mas
between Proxima b and its host star requires the use of visible wavelengths to
spatially resolve the planet on a 8.2-m telescope. At an estimated
planet-to-star contrast of ~10^-7 in reflected light, Proxima b is extremely
challenging to detect with SPHERE alone. However, the combination of a
~10^3-10^4 contrast enhancement from SPHERE to the high spectral resolution of
ESPRESSO can reveal the planetary spectral features and disentangle them from
the stellar ones. Results. We find that significant but realistic upgrades to
SPHERE and ESPRESSO would enable a 5-sigma detection of the planet and yield a
measurement of its true mass and albedo in 20-40 nights of telescope time,
assuming an Earth-like atmospheric composition. Moreover, it will be possible
to probe the O2 bands at 627, 686 and 760 nm, the water vapour band at 717 nm,
and the methane band at 715 nm. In particular, a 3.6-sigma detection of O2
could be made in about 60 nights of telescope time. Those would need to be
spread over 3 years considering optimal observability conditions for the
planet. Conclusions. The very existence of Proxima b and the SPHERE-ESPRESSO
synergy represent a unique opportunity to detect biosignatures on an exoplanet
in the near future. It is also a crucial pathfinder experiment for the
development of Extremely Large Telescopes and their instruments (abridged).


title:
Uses of Sampling Techniques & Inventory Control with Capacity
  Constraints

abstract:
  The main aim of the present book is to suggest some improved estimators using
auxiliary and attribute information in case of simple random sampling and
stratified random sampling and some inventory models related to capacity
constraints. This volume is a collection of five papers, written by six
co-authors (listed in the order of the papers): Dr. Rajesh Singh, Dr. Sachin
Malik, Dr. Florentin Smarandache, Dr. Neeraj Kumar, Mr. Sanjey Kumar & Pallavi
Agarwal. In the first chapter authors suggest an estimator using two auxiliary
variables in stratified random sampling for estimating population mean. In
second chapter they proposed a family of estimators for estimating population
means using known value of some population parameters. In Chapter third an
almost unbiased estimator using known value of some population parameter(s)
with known population proportion of an auxiliary variable has been used. In
Chapter four the authors investigates a fuzzy economic order quantity model for
two storage facility. The demand, holding cost, ordering cost, storage capacity
of the own - warehouse are taken as trapezoidal fuzzy numbers. In Chapter five
a two-warehouse inventory model deals with deteriorating items, with stock
dependent demand rate and model affected by inflation under the pattern of time
value of money over a finite planning horizon. Shortages are allowed and
partially backordered depending on the waiting time for the next replenishment.
The purpose of this model is to minimize the total inventory cost by using the
genetic algorithm. This book will be helpful for the researchers and students
who are working in the field of sampling techniques and inventory control.


title: Graph labeling games

abstract:
  We propose the study of many new variants of two-person graph labeling games.
Hardly anything has been done in this wide open field so far.


title: Optical patterning of trapped charge in nitrogen-doped diamond

abstract:
  The nitrogen-vacancy (NV) centre in diamond is emerging as a promising
platform for solid-state quantum information processing and nanoscale
metrology. Of interest in these applications is the manipulation of the NV
charge, which can be attained by optical excitation. Here we use two-color
optical microscopy to investigate the dynamics of NV photo-ionization, charge
diffusion, and trapping in type-1b diamond. We combine fixed-point laser
excitation and scanning fluorescence imaging to locally alter the concentration
of negatively charged NVs, and to subsequently probe the corresponding
redistribution of charge. We uncover the formation of spatial patterns of
trapped charge, which we qualitatively reproduce via a model of the interplay
between photo-excited carriers and atomic defects. Further, by using the NV as
a probe, we map the relative fraction of positively charged nitrogen upon
localized optical excitation. These observations may prove important to
transporting quantum information between NVs or to developing
three-dimensional, charge-based memories.


title: Three-body systems in pionless effective field theory

abstract:
  Investigations of three-body nuclear systems using pionless effective field
theory ($\mathrm{EFT}_{\not{\pi}}$) are reviewed. The history of
$\mathrm{EFT}_{\not{\pi}}$ in $nd$ and $pd$ scattering is briefly discussed and
emphasis put on the use of strict perturbative techniques. In addition
renormalization issues appearing in $pd$ scattering are also presented. Bound
state calculations are addressed and new perturbative techniques for describing
them are highlighted. Three-body breakup observables in $nd$ scattering are
also considered and the utility of $\mathrm{EFT}_{\not{\pi}}$ for addressing
them.


title:
Capitulation in the absolutely abelian extensions of some number fields
  II

abstract:
  We study the capitulation of $2$-ideal classes of an infinite family of
imaginary biquadratic number fields consisting of fields $k =Q(\sqrt{pq_1q_2},
i)$, where $i=\sqrt{-1}$ and $q_1\equiv q_2\equiv-p\equiv-1 \pmod 4$ are
different primes. For each of the three quadratic extensions $K/k$ inside the
absolute genus field $k^{(*)}$ of $k$, we compute the capitulation kernel of
$K/k$. Then we deduce that each strongly ambiguous class of $k/Q(i)$
capitulates already in $k^{(*)}$.


title:
Phase retrieval with random Gaussian sensing vectors by alternating
  projections

abstract:
  We consider a phase retrieval problem, where we want to reconstruct a
$n$-dimensional vector from its phaseless scalar products with $m$ sensing
vectors. We assume the sensing vectors to be independently sampled from complex
normal distributions. We propose to solve this problem with the classical
non-convex method of alternating projections. We show that, when $m\geq Cn$ for
$C$ large enough, alternating projections succeed with high probability,
provided that they are carefully initialized. We also show that there is a
regime in which the stagnation points of the alternating projections method
disappear, and the initialization procedure becomes useless. However, in this
regime, $m$ has to be of the order of $n^2$. Finally, we conjecture from our
numerical experiments that, in the regime $m=O(n)$, there are stagnation
points, but the size of their attraction basin is small if $m/n$ is large
enough, so alternating projections can succeed with probability close to $1$
even with no special initialization.


title: Fibration of log-general type space over quasi-abelian varieties

abstract:
  We show that there exists no smooth fibration of a smooth complex
quasi-projective variety of log-general type over a quasi-abelian variety. The
proof uses M. Popa and C. Schnell's construction of Higgs bundle.


title:
Dynamical theory of single photon transport in a one-dimensional
  waveguide coupled to identical and non-identical emitters

abstract:
  We develop a general dynamical theory for studying a single photon transport
in a one-dimensional (1D) waveguide coupled to multiple emitters which can be
either identical or non-identical. In this theory, both the effects of the
waveguide and non-waveguide vacuum modes are included. This theory enables us
to investigate the propagation of an emitter excitation or an arbitrary single
photon pulse along an array of emitters coupled to a 1D waveguide. The
dipole-dipole interaction induced by the non-waveguide modes, which is usually
neglected in the literatures, can significantly modify the dynamics of the
emitter system as well as the characteristics of output field if the emitter
separation is much smaller than the resonance wavelength. Non-identical
emitters can also strongly couple to each other if their energy difference is
smaller than or of the order of the dipole-dipole energy shift. Interestingly,
if their energy difference is close but non-zero, a very narrow transparency
window around the resonance frequency can appear which does not occur for
identical emitters. This phenomenon may find important applications in quantum
waveguide devices such as optical switch and ultra narrow single photon
frequency comb generator.


title:
A note on simultaneous nonvanishing of Dirichlet $L$-functions and
  twists of Hecke-Maass $L$-functions

abstract:
  In this note, we prove that given a Hecke-Maass cusp form $f$ for
$SL_2(\mathbb{Z})$ and a sufficiently large integer $q=q_1q_2$ with $q_j\asymp
\sqrt{q}$ being prime numbers for $j=1,2$, there exists a primitive Dirichlet
character $\chi$ of conductor $q$ such that $L\left(\frac{1}{2},f\otimes
\chi\right)L\left(\frac{1}{2},\chi\right)\neq 0$. To prove this, we establish
asymptotic formulas of $L\left(\frac{1}{2},f\otimes
\chi\right)L\left(\frac{1}{2},\chi\right)$ over the family of even primitive
Dirichlet characters $\chi$ of conductor $q$ for more general $q$.


title:
A first principles TDDFT framework for spin and time-resolved ARPES in
  periodic systems

abstract:
  We present a novel theoretical approach to simulate spin, time and
angular-resolved photoelectron spectroscopy (ARPES) from first principles that
is applicable to surfaces, thin films, few layer systems, and low-dimensional
nanostructures. The method is based on a general formulation in the framework
of time-dependent density functional theory (TDDFT) to describe the real
time-evolution of electrons escaping from a surface under the effect of any
external (arbitrary) laser field. By extending the so called t-SURFF method to
periodic systems one can calculate the final photoelectron spectrum by
collecting the flux of the ionization current trough an analysing surface. The
resulting approach, that we named t-SURFFP, allows to describe a wide range of
irradiation conditions without any assumption on the dynamics of the ionization
process allowing for pump-probe simulations on an equal footing. To illustrate
the wide scope of applicability of the method we present applications to
graphene, mono- and bi-layer WSe$_2$, and hexagonal BN under different laser
configurations.


title:
Using Spatial Pooler of Hierarchical Temporal Memory to classify noisy
  videos with predefined complexity

abstract:
  This paper examines the performance of a Spatial Pooler (SP) of a
Hierarchical Temporal Memory (HTM) in the task of noisy object recognition. To
address this challenge, a dedicated custom-designed system based on the SP,
histogram calculation module and SVM classifier was implemented. In addition to
implementing their own version of HTM, the authors also designed a profiler
which is capable of tracing all of the key parameters of the system. This was
necessary, since an analysis and monitoring of the system performance turned
out to be extremely difficult using conventional testing and debugging tools.
The system was initially trained on artificially prepared videos without noise
and then tested with a set of noisy video streams. This approach was intended
to mimic a real life scenario where an agent or a system trained to deal with
ideal objects faces a task of classifying distorted and noisy ones in its
regular working conditions. The authors conducted a series of experiments for
various macro parameters of HTM SP, as well as for different levels of video
reduction ratios. The experiments allowed them to evaluate the performance of
two different system setups (i.e. 'Multiple HTMs' and 'Single HTM') under
various noise conditions with 32--frame video files. Results of all the tests
were compared to SVM baseline setup. It was determined that the system
featuring SP is capable of achieving approximately 12 times the noise reduction
for a video signal with with distorted bits accounting for 13\% of the total.
Furthermore, the system featuring SP performed better also in the experiments
without a noise component and achieved a max F1 score of 0.96. The experiments
also revealed that a rise of column and synapse number of SP has a substantial
impact on the performance of the system. Consequently, the highest F1 score
values were obtained for 256 and 4096 synapses and columns respectively.


title:
Temperature restrictions for materials used in aerospace industry for
  the near-sun orbits

abstract:
  For near-Sun missions, the spacecraft approaches very close to the Sun and
space environmental effects become relevant. Strong restrictions on how much
close it can get derive from the maximum temperature that the used materials
can stand, in order not to compromise the spacecraft's activity and
functionalities. In other words, the minimum perihelion distance of a given
mission can be determined based on the materials' temperature restrictions. The
temperature of an object in space depends on its optical properties:
reflectivity, absorptivity, transmissivity, and emissivity. Usually, it is
considered as an approximation that the optical properties of materials are
constant. However, emissivity depends on temperature. The consideration of the
temperature dependence of emissivity and conductivity of materials used in the
aerospace industry leads to the conclusion that the temperature dependence on
the heliocentric distance is different from the case of constant optical
properties [1]. Particularly, taking into account that emissivity is directly
proportional to the temperature, the temperature of an object increases as
$r{}^{-2/5}$ when the heliocentric distance $r$ decreases. This means that the
same temperature will actually be reached at a different distance and,
eventually, the spacecraft will be allowed to approach closer to the Sun
without compromising its activities. We focused on metals used for aerospace
structures (Al, Ti), however our analysis can be extended to all kinds of
composite materials, once their optical properties - in particular emissivity -
are defined.


title: Efficient Error-tolerant Search on Knowledge Graphs

abstract:
  Edge-labeled graphs are widely used to describe relationships between
entities in a database. Given a query subgraph that represents an example of
what the user is searching for, we study the problem of efficiently searching
for similar subgraphs in a large data graph, where the similarity is defined in
terms of the well-known graph edit distance. We call these queries
"error-tolerant exemplar queries" since matches are allowed despite small
variations in the graph structure and the labels. The problem in its general
case is computationally intractable, but efficient solutions are reachable for
labeled graphs under well-behaved distribution of the labels, commonly found in
knowledge graphs. We propose two efficient exact algorithms, based on a
filtering-and-verification framework, for finding subgraphs in a large data
graph that are isomorphic to a query graph under some edit operations. Our
filtering scheme, which uses the neighbourhood structure around a node and the
presence or absence of paths, significantly reduces the number of candidates
that are passed to the verification stage. Moreover, we analyze the costs of
our algorithms and the conditions under which one algorithm is expected to
outperform the other. Our analysis identifies some of the variables that affect
the cost, including the number and the selectivity of query edge labels and the
degree of nodes in the data graph, and characterizes their relationships. We
empirically evaluate the effectiveness of our filtering schemes and queries,
the efficiency of our algorithms and the reliability of our cost models on real
datasets.